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Sample records for total root length

  1. Role and significance of total phenols during rooting of Protea ...

    African Journals Online (AJOL)

    Reviewer

    2011-10-03

    Oct 3, 2011 ... fluctuations in total phenol concentration of different parts ... Rooting percentage, mean root dry mass and mean number of roots according to root length ... differences at P ≤ 0.05 based on chi-square; 2different letters in.

  2. Accuracy of working length determination with root ZX apex locator ...

    African Journals Online (AJOL)

    The purpose of this study was to clinically compare working length (WL) determination with root ZX apex locator and radiography, and then compare them with direct visualization method ex vivo. A total of 75 maxillary central and lateral incisors were selected. Working length determination was carried out using radiographic ...

  3. Radiographic versus electronic root canal working length determination

    Directory of Open Access Journals (Sweden)

    Lumnije Kqiku

    2011-01-01

    Conclusions: The present ex vivo study showed that electronic root canal working length determination is not superior to radiographic methods. Both methods provided a good performance in determining the root canal working length.

  4. Effects of fine root length density and root biomass on soil preferential flow in forest ecosystems

    Directory of Open Access Journals (Sweden)

    Yinghu Zhang

    2015-04-01

    Full Text Available Aim of study: The study was conducted to characterize the impacts of plant roots systems (e.g., root length density and root biomass on soil preferential flow in forest ecosystems. Area of study: The study was carried out in Jiufeng National Forest Park, Beijing, China. Material and methods: The flow patterns were measured by field dye tracing experiments. Different species (Sophora japonica Linn,Platycladus orientalis Franco, Quercus dentata Thunbwere quantified in two replicates, and 12 soil depth were applied. Plant roots were sampled in the sieving methods. Root length density and root biomass were measured by WinRHIZO. Dye coverage was implied in the image analysis, and maximum depth of dye infiltration by direct measurement. Main results: Root length density and root biomass decreased with the increasing distance from soil surface, and root length density was 81.6% higher in preferential pathways than in soil matrix, and 66.7% for root biomass with respect to all experimental plots. Plant roots were densely distributed in the upper soil layers. Dye coverage was almost 100% in the upper 5-10 cm, but then decreased rapidly with soil depth. Root length density and root biomass were different from species: Platycladus orientalis Franco > Quercus dentata Thunb > Sophora japonica Linn. Research highlights: The results indicated that fine roots systems had strong effects on soil preferential flow, particularly root channels enhancing nutrition transport across soil profiles in forest dynamics.

  5. Fine Mapping of QUICK ROOTING 1 and 2, Quantitative Trait Loci Increasing Root Length in Rice.

    Science.gov (United States)

    Kitomi, Yuka; Nakao, Emari; Kawai, Sawako; Kanno, Noriko; Ando, Tsuyu; Fukuoka, Shuichi; Irie, Kenji; Uga, Yusaku

    2018-02-02

    The volume that the root system can occupy is associated with the efficiency of water and nutrient uptake from soil. Genetic improvement of root length, which is a limiting factor for root distribution, is necessary for increasing crop production. In this report, we describe identification of two quantitative trait loci (QTLs) for maximal root length, QUICK ROOTING 1 ( QRO1 ) on chromosome 2 and QRO2 on chromosome 6, in cultivated rice ( Oryza sativa L.). We measured the maximal root length in 26 lines carrying chromosome segments from the long-rooted upland rice cultivar Kinandang Patong in the genetic background of the short-rooted lowland cultivar IR64. Five lines had longer roots than IR64. By rough mapping of the target regions in BC 4 F 2 populations, we detected putative QTLs for maximal root length on chromosomes 2, 6, and 8. To fine-map these QTLs, we used BC 4 F 3 recombinant homozygous lines. QRO1 was mapped between markers RM5651 and RM6107, which delimit a 1.7-Mb interval on chromosome 2, and QRO2 was mapped between markers RM20495 and RM3430-1, which delimit an 884-kb interval on chromosome 6. Both QTLs may be promising gene resources for improving root system architecture in rice. Copyright © 2018 Kitomi et al.

  6. Fine Mapping of QUICK ROOTING 1 and 2, Quantitative Trait Loci Increasing Root Length in Rice

    Directory of Open Access Journals (Sweden)

    Yuka Kitomi

    2018-02-01

    Full Text Available The volume that the root system can occupy is associated with the efficiency of water and nutrient uptake from soil. Genetic improvement of root length, which is a limiting factor for root distribution, is necessary for increasing crop production. In this report, we describe identification of two quantitative trait loci (QTLs for maximal root length, QUICK ROOTING 1 (QRO1 on chromosome 2 and QRO2 on chromosome 6, in cultivated rice (Oryza sativa L.. We measured the maximal root length in 26 lines carrying chromosome segments from the long-rooted upland rice cultivar Kinandang Patong in the genetic background of the short-rooted lowland cultivar IR64. Five lines had longer roots than IR64. By rough mapping of the target regions in BC4F2 populations, we detected putative QTLs for maximal root length on chromosomes 2, 6, and 8. To fine-map these QTLs, we used BC4F3 recombinant homozygous lines. QRO1 was mapped between markers RM5651 and RM6107, which delimit a 1.7-Mb interval on chromosome 2, and QRO2 was mapped between markers RM20495 and RM3430-1, which delimit an 884-kb interval on chromosome 6. Both QTLs may be promising gene resources for improving root system architecture in rice.

  7. Changes in root lengths of maxillary incisors during orthodontic retention period

    Directory of Open Access Journals (Sweden)

    Ravanmehr H

    2006-01-01

    Full Text Available Background and Aim: External apical root resorption is a common iatrogenic consequence of orthodontic treatment. Much controversy exists in the literature about changes in root lengths at post treatment periods. Although many practitioners believe that resorption becomes stable after active treatment, quantitative data are scarce. The purpose of this study was to determine quantitative changes in root lengths of maxillary incisors during fixed orthodontic post treatment period, and to assess if it is influenced by gender and factors related to active treatment. Materials and Methods: This was a case cross over study, performed on 80 patients (52 females and 28 males aged between 13 and 22 years. At debonding stage and beginning of retention phase of fixed orthodontic treatment, Hawley type retainer was fabricated for maxillary arch. Periapical radiographs of maxillary incisors using standard parallel technique were obtained immediately after debonding, and 3 and 7 months later. Crown and root lengths of maxillary incisors were measured using computer program. Changes in root lengths were calculated considering correction factors. Also associations between some factors and the change in root lengths during post treatment periods were assessed. These included gender, type of treatment plan (non extraction/extraction, technique (standard edgewise/straight-wire edgewise and duration of active treatment (less than 2 years/2 years and more. T-test and 4-way ANOVA were used for statistical analysis with P0.05 as the limit of significance. Results: No significant relation was found between apical root resorption of maxillary central incisors and time elapsed after treatment. Significant relation was observed between apical root resorption of maxillary lateral incisors and the length of post treatment period. No significant relation was found between root length changes of maxillary incisors during post treatment period and gender, type of treatment

  8. Sample preparation and scanning protocol for computerised analysis of root length and diameter

    NARCIS (Netherlands)

    Bouma, T.J.; Nielsen, K.F.; Koutstaal, B.P.

    2000-01-01

    Root length and diameter distribution are important characteristics to be considered when describing and comparing root systems. Root length and root-diameter distribution may be obtained in two ways: by microscopical measurements, which are laborious, or by computerised analysis, which is fast but

  9. Working Length Determination of Root Canal of Young Permanent ...

    African Journals Online (AJOL)

    Working Length Determination of Root Canal of Young Permanent Tooth: An In Vitro Study. A Diwanji, AS Rathore, R Arora, V Dhar, A Madhusudan, J Doshi. Abstract. Background: Determination of correct working length is one of the keys to success in endodontic therapy. Aim: The aim of this study was to evaluate the ...

  10. Quantitative Classification of Rice (Oryza sativa L.) Root Length and Diameter Using Image Analysis.

    Science.gov (United States)

    Gu, Dongxiang; Zhen, Fengxian; Hannaway, David B; Zhu, Yan; Liu, Leilei; Cao, Weixing; Tang, Liang

    2017-01-01

    Quantitative study of root morphological characteristics of plants is helpful for understanding the relationships between their morphology and function. However, few studies and little detailed and accurate information of root characteristics were reported in fine-rooted plants like rice (Oryza sativa L.). The aims of this study were to quantitatively classify fine lateral roots (FLRs), thick lateral roots (TLRs), and nodal roots (NRs) and analyze their dynamics of mean diameter (MD), lengths and surface area percentage with growth stages in rice plant. Pot experiments were carried out during three years with three rice cultivars, three nitrogen (N) rates and three water regimes. In cultivar experiment, among the three cultivars, root length of 'Yangdao 6' was longest, while the MD of its FLR was the smallest, and the mean diameters for TLR and NR were the largest, the surface area percentage (SAP) of TLRs (SAPT) was the highest, indicating that Yangdao 6 has better nitrogen and water uptake ability. High N rate increased the length of different types of roots and increased the MD of lateral roots, decreased the SAP of FLRs (SAPF) and TLRs, but increased the SAP of NRs (SAPN). Moderate decrease of water supply increased root length and diameter, water stress increased the SAPF and SAPT, but decreased SAPN. The quantitative results indicate that rice plant tends to increase lateral roots to get more surface area for nitrogen and water uptake when available assimilates are limiting under nitrogen and water stress environments.

  11. Root Length and Anatomy of Impacted Maxillary Canines in Patients with Unilateral Maxillary Canine Impaction

    Directory of Open Access Journals (Sweden)

    Mostfa Shahabi

    2017-09-01

    Full Text Available Introduction: Canine impaction is a common occurrence. In this study, we sought to investigate the root anatomy and length of impacted canines and lateral incisor adjacent to impacted maxillary canine. Materials and Methods: In this retrospective study, three-dimensional tomographic imaging was performed on 26 patients with unilateral maxillary canine impaction. In this study, we evaluated root length and anatomy of impacted canines, in terms of resorption intensity and curvature, with Planmeca Romexis Viewer 4.0. Furthermore, crown shape as well as root length and anatomy of the lateral incisors adjacent to impacted canines were investigated and compared with the other side on the dental arch, where canine eruption was normal. Results: Root length of impacted canines was significantly lower than that of normal canines (P=0.011. There were no significant differences between root length of lateral incisors adjacent to impacted canines and root length of lateral incisors adjacent to normal canines (P=0.221. Moreover, the resorption intensity of the adjacent lateral incisors was higher than that of the impacted canines. No significant differences were noted in root resorption intensity between the lateral incisors adjacent to the imacted canines and the lateral incisors adjacent to normal canines (P=0.36. In addition, resorption intensity was significantly higher in impacted canines than in normal canines (P=0.024. Root anatomy of impacted canines was not significantly different from that of normal canines (P=0.055. The crown shape of the lateral incisors adjacent to impacted canines was not significantly different from that of the lateral incisors adjacent to normal canines (P=0.052. Conclusion: Impaction can probably affect root length and canine resorption severity. However, root and crown shape of lateral incisors cannot always be associated with canine impaction.

  12. Quantitative Classification of Rice (Oryza sativa L.) Root Length and Diameter Using Image Analysis

    Science.gov (United States)

    Gu, Dongxiang; Zhen, Fengxian; Hannaway, David B.; Zhu, Yan; Liu, Leilei; Cao, Weixing; Tang, Liang

    2017-01-01

    Quantitative study of root morphological characteristics of plants is helpful for understanding the relationships between their morphology and function. However, few studies and little detailed and accurate information of root characteristics were reported in fine-rooted plants like rice (Oryza sativa L.). The aims of this study were to quantitatively classify fine lateral roots (FLRs), thick lateral roots (TLRs), and nodal roots (NRs) and analyze their dynamics of mean diameter (MD), lengths and surface area percentage with growth stages in rice plant. Pot experiments were carried out during three years with three rice cultivars, three nitrogen (N) rates and three water regimes. In cultivar experiment, among the three cultivars, root length of ‘Yangdao 6’ was longest, while the MD of its FLR was the smallest, and the mean diameters for TLR and NR were the largest, the surface area percentage (SAP) of TLRs (SAPT) was the highest, indicating that Yangdao 6 has better nitrogen and water uptake ability. High N rate increased the length of different types of roots and increased the MD of lateral roots, decreased the SAP of FLRs (SAPF) and TLRs, but increased the SAP of NRs (SAPN). Moderate decrease of water supply increased root length and diameter, water stress increased the SAPF and SAPT, but decreased SAPN. The quantitative results indicate that rice plant tends to increase lateral roots to get more surface area for nitrogen and water uptake when available assimilates are limiting under nitrogen and water stress environments. PMID:28103264

  13. The accuracy of the radiographic method in root canal length measurement

    International Nuclear Information System (INIS)

    Jo, Eun Young; Park, Chang Seo

    1998-01-01

    For the successful endodontic treatment, root canal should be cleaned thoroughly by accurate mechanical and chemical canal preparation and sealed completely with canal filling material without damaging the periapical tissues. The accuracy of the root canal length measurement is a prerequisite for the success of the endodontic treatment, and the root canal length is often determined by the standard periapical radiographs and digital tactile sense. In this study, the accuracy and the clinical usefulness of Digora, an intraoral digital imaging processor and the conventional standard radiographs were compared by measuring the length from the top of the file to the root apex. 30 single rooted premolars were invested in a uniformly sized blocks and No.25 K-file was inserted into and fixed in each canal. Each block was placed in equal distance and position to satisfy the principle of the bisecting angle and paralleling techniques and Digora system's image and standard periapical radiographs were taken. Each radiograph was examined by 3 different observers by measuring the length from top of the file to the root apex and each data was compared and analyzed. The results were as follows; 1. In the bisecting angle technique, the average difference between the Digora system and standard periapical radiograph was 0.002 mm and the standard deviation was 0.341 mm which showed no statistically significant difference between the two systems (p>0.05). Also, in the paralleling technique, the average difference between these two system was 0.007 mm and the standard deviation was 0.323 mm which showed no statistically significant difference between the two systems (p>0.05). 2. In Digora system, the average difference between the bisecting angle and paralleling technique was -0.336 mm and the standard deviation was 0.472 mm which showed a statistically significant difference between the two techniques (p 0.05). In conclusion, the determination of the root canal length by using the

  14. Analysis of aneuploid lines of bread wheat to map chromosomal locations of genes controlling root hair length.

    Science.gov (United States)

    Liu, Miao; Rathjen, Tina; Weligama, Kumara; Forrest, Kerrie; Hayden, Matthew; Delhaize, Emmanuel

    2017-06-01

    Long root hairs enable the efficient uptake of poorly mobile nutrients such as phosphorus. Mapping the chromosomal locations of genes that control root hair length can help exploit the natural variation within crops to develop improved cultivars. Genetic stocks of the wheat cultivar 'Chinese Spring' were used to map genes that control root hair length. Aneuploid stocks of 'Chinese Spring' were screened using a rapid method based on rhizosheath size and then selected lines were assayed for root hair length to identify chromosomes harbouring genes controlling root hair length. A series of lines with various fractional deletions of candidate chromosomes were then screened to map the root hair loci more accurately. A line with a deletion in chromosome 5A was analysed with a 90 000 single nucleotide polymorphism (SNP) array. The phosphorus acquisition efficiency (PAE) of one deletion line was compared with that of euploid 'Chinese Spring' by growing the seedlings in pots at low and luxury phosphorus supplies. Chromosomes 1A, 1D and 5A were found to harbour genes controlling root hair length. The 90 000 SNP array identified two candidate genes controlling root hair length located on chromosome 5A. The line with a deletion in chromosome 5A had root hairs that were approx. 20 % shorter than euploid 'Chinese Spring', but this was insufficient to reduce its PAE. A rapid screen for rhizosheath size enabled chromosomal regions controlling root hair length to be mapped in the wheat cultivar 'Chinese Spring' and subsequent analysis with an SNP array identified candidate genes controlling root hair length. The difference in root hair length between euploid 'Chinese Spring' and a deletion line identified in the rapid screen was still apparent, albeit attenuated, when the seedlings were grown on a fully fertilized soil. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  15. Polyethylene Glycol (PEG-Treated Hydroponic Culture Reduces Length and Diameter of Root Hairs of Wheat Varieties

    Directory of Open Access Journals (Sweden)

    Arif Hasan Khan Robin

    2015-10-01

    Full Text Available Wheat is an important cereal crop worldwide that often suffers from moisture deficits at the reproductive stage. Polyethylene glycol (PEG-treated hydroponic conditions create negative osmotic potential which is compared with moisture deficit stress. An experiment was conducted in a growth chamber to study the effects of PEG on root hair morphology and associated traits of wheat varieties. Plants of 13 wheat varieties were grown hydroponically and three different doses of PEG 6000 (w/v: 0% (control, 0.3% and 0.6% (less than −1 bar were imposed on 60 days after sowing for 20 days’ duration. A low PEG concentration was imposed to observe how initial low moisture stress might affect root hair development. PEG-treated hydroponic culture significantly decreased root hair diameter and length. Estimated surface area reduction of root hairs at the main axes of wheat plants was around nine times at the 0.6% PEG level compared to the control plants. Decrease in root hair diameter and length under PEG-induced culture decreased “potential” root surface area per unit length of main root axis. A negative association between panicle traits, length and dry weight and the main axis length of young roots indicated competition for carbon during their development. Data provides insight into how a low PEG level might alter root hair development.

  16. Resorption of lateral incisors during canine eruption: two clinical cases with focus on root length and heredity

    DEFF Research Database (Denmark)

    Zargham, Mostafa; Kjær, Inger

    2016-01-01

    Introduction: It is well-known that pressure from orthodontic appliance can provoke root resorption in dentitions with short roots. The purpose of this case report is to demonstrate two clinical cases with focus on root length in dentitions exposed due to pressure from erupting teeth...... resorption on her lateral incisor roots, extremely short roots in the central incisors, and short roots. The intraoral photos demonstrated light crowding in the maxilla. The orthopantomogram of the girl’s mother demonstrated extremely short roots in general. Conclusion: This pilot study indicates that short...... root length in general and abnormal incisor morphology are phenotypic traits that were characteristic for both girls who presented with severe lateral incisor resorption due to erupting canines. Furthermore, short roots were also demonstrated in the mothers. Accordingly, short root length in general...

  17. The effect of cutting length on the rooting and growth of subtropical ...

    African Journals Online (AJOL)

    The length of a cutting can affect both the rooting and plug colonisation of container-grown stock. Using hedges from conventional clonebanks established in the ground, four cutting length treatments (13, 10, 8 and 5 cm) were tested using five Eucalyptus grandis × E. urophylla clones. The smallest cutting length had the ...

  18. The Effects of Two Different Deficit Irrigation Managements on the Root Length of Maize

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    M. Gheysari

    2015-06-01

    Full Text Available The response of root to water stress is one of the most important parameters for researchers. Study of growth and distribution of root under different irrigation managements helpsresearchersto a better understanding of soil water content, and the availability of water and nutrition in water stress condition. To investigate the effects of four levels of irrigation under two different deficit irrigation managements on the root length of maize, a study was conducted in 2009. Irrigation managements included fixed irrigation interval-variable irrigation depth (M1 and variable irrigation interval-fixed irrigation depth (M2. Maize plants were planted in 120 large 110-liter containers in a strip-plot design in a randomized complete block with three replications. Root data sampling was done after root washing in five growth stages. The results showed that the effect of irrigation levels on root length was significant (P

  19. Accuracy of two root canal length measurement devices integrated into rotary endodontic motors when removing gutta-percha from root-filled teeth.

    Science.gov (United States)

    Uzun, O; Topuz, O; Tinaz, C; Nekoofar, M H; Dummer, P M H

    2008-09-01

    To evaluate ex vivo the accuracy of the integrated electronic root canal length measurement devices within TCM Endo V and Tri Auto ZX motors whilst removing gutta-percha and sealer from filled root canals. Forty freshly extracted maxillary and mandibular incisor teeth with mature apices were selected. Following access cavity preparation, the length of the root canals were measured visually 0.5 mm short of the major foramen (TL). The canals were prepared using the HERO 642 system and then filled with gutta-percha and AH26 sealer using a lateral compaction technique. After 7 days the coronal temporary filling was removed and the roots mounted in an alginate experimental model. The roots were then randomly divided in two groups. The access cavities were filled with chloroform to soften the gutta-percha and allow its penetration using the Tri Auto ZX and the TCM Endo V devices in groups 1 and 2, respectively. The 'automatic apical reverse function' (ARL) of both devices was set to start at the 0.5 setting and the rotary instrument inserted inside the root canal until a beeping sound was heard and the rotation of the file stopped automatically. Once the auto reverse function had been initiated, the foot pedal of the motor was inactivated and the rubber stop placed against the reference point. The distance between the file tip and rubber stop was measured using a digital calliper to 0.01 mm accuracy (ARL). Then, a size 20, 0.02 taper instrument was attached to each device and inserted into the root canals without rotary motion until the integrated ERCLMDs positioned the instrument tips at the 0.5 setting as suggested by the devices. This length was again measured using a digital calliper (EL). The Mann-Whitney U-test was used to investigate statistical differences between the true canal length and those indicated by the two devices when used in 'automatic ARL and when inserted passively (EL). In the presence of gutta-percha, sealer and chloroform, the auto

  20. Water transport through tomato roots infected with Meloidogyne incognita.

    NARCIS (Netherlands)

    Dorhout, R.; Gommers, F.J.; Kollöffel, C.

    1991-01-01


    The effect of Meloidogyne incognita on water flow in tomato roots was investigated in rooted split-stem cuttings. Total water flow through infected root parts was significantly lower than through comparable uninfected parts. Total water uptake was correlated with total length of the root

  1. Root Length and Anatomy of Impacted Maxillary Canines in Patients with Unilateral Maxillary Canine Impaction

    OpenAIRE

    Mostfa Shahabi; Maryam Omidkhoda; Seyedeh Haniyeh Omidi; Seyed Hosein Hoseini Zarch

    2017-01-01

    Introduction: Canine impaction is a common occurrence. In this study, we sought to investigate the root anatomy and length of impacted canines and lateral incisor adjacent to impacted maxillary canine. Materials and Methods: In this retrospective study, three-dimensional tomographic imaging was performed on 26 patients with unilateral maxillary canine impaction. In this study, we evaluated root length and anatomy of impacted canines, in terms of resorption intensity and curvature, with Planme...

  2. Resorption of Lateral Incisors during Canine Eruption: Two Clinical Cases with Focus on Root Lengths and Heredity

    Directory of Open Access Journals (Sweden)

    Mostafa Zargham

    2016-01-01

    Full Text Available Introduction: It is well-known that pressure from orthodontic appliance can provoke root resorption in dentitions with short roots. The purpose of this case report is to demonstrate two clinical cases with focus on root length in dentitions exposed due to pressure from erupting teeth. This is a pilot study aimed to improve diagnostics for avoiding the resorption of lateral maxillary incisors by pressure from erupting canines. Case Report: The first reported case is of a girl who was 11 years and 7 months old when radiographs showed severe resorption of the lateral incisors, along with malformed central incisors and short roots. The intraoral photos demonstrated light crowding in the maxilla. The orthopantomogram of the girl’s mother demonstrated several short roots. The second reported case is of a girl who was 9 years and 5 months old when radiographs demonstrated nearly complete resorption on her lateral incisor roots, extremely short roots in the central incisors, and short roots. The intraoral photos demonstrated light crowding in the maxilla. The orthopantomogram of the girl’s mother demonstrated extremely short roots in general. Conclusion: This pilot study indicates that short root length in general and abnormal incisor morphology are phenotypic traits that were characteristic for both girls who presented with severe lateral incisor resorption due to erupting canines. Furthermore, short roots were also demonstrated in the mothers. Accordingly, short root length in general could be a phenotypic trait, which should be diagnosed early for preventing severe resorption of lateral incisors during canine eruption.

  3. Role and significance of total phenols during rooting of Protea ...

    African Journals Online (AJOL)

    The high total phenol content was associated with significantly higher rooting percentage and increased the number of roots formed. Blanching reduced the time needed for the cuttings to root sufficiently to be transplanted to the field by 30 days. Analyses of different parts of cuttings throughout the entire rooting period ...

  4. The Accuracy of the Digital imaging system and the frequency dependent type apex locator in root canal length measurement

    International Nuclear Information System (INIS)

    Lee, Byoung Rib; Park, Chang Seo

    1998-01-01

    In order to achieve a successful endodontic treatment, root canals must be obturated three-dimensionally without causing any damage to apical tissues. Accurate length determination of the root canal is critical in this case. For this reason, I've used the conventional periapical radiography, Digora (digital imaging system) and Root ZX (the frequency dependent type apex locator) to measure the length of the canal and compare it with the true length obtained by cutting the tooth in half and measuring the length between the occlusal surface and the apical foramen. From the information obtained by these measurements, I was able to evaluate the accuracy and clinical usefulness of each systems, whether the thickness of files used in endodontic therapy has any effect on the measuring systems was also evaluated in an effort to simplify the treatment planning phase of endodontic treatment. 29 canals of 29 sound premolars were measured with no 15, no 20, no 25 files by 3 different dentists each using the periapical radiography, Digora and Root ZX. The measurements were then compared with the true length. The results were as follows ; 1. In comparing mean discrepancies between measurements obtained by using periapical radiography (mean error : -0.449 ± 0.444 mm), Digora (mean error : -0.417 ± 0.415 mm) and Root ZX (mean error : 0.123 ± 0.458 mm) with true length, periapical radiography and Digora system had statistically significant differences (p 0.05). 2. By subtracting values obtained by using periapical radiography, Digora and Root ZX from the true length and making a distribution table of their absolute values, the following analysis was possible. In the case of periapical film, 140 out of 261 (53.6%) were clinically acceptable satisfying the margin of error of less than 0.5 mm, 151 out of 261 (53,6%) were acceptable in the Digora system while Root ZX had 197 out of 261 (75.5%) within the limits of 0.5 mm margin of error. 3. In determining whether the thickness of

  5. Pulp regeneration in a full-length human tooth root using a hierarchical nanofibrous microsphere system.

    Science.gov (United States)

    Li, Xiangwei; Ma, Chi; Xie, Xiaohua; Sun, Hongchen; Liu, Xiaohua

    2016-04-15

    While pulp regeneration using tissue engineering strategy has been explored for over a decade, successful regeneration of pulp tissues in a full-length human root with a one-end seal that truly simulates clinical endodontic treatment has not been achieved. To address this challenge, we designed and synthesized a unique hierarchical growth factor-loaded nanofibrous microsphere scaffolding system. In this system, vascular endothelial growth factor (VEGF) binds with heparin and is encapsulated in heparin-conjugated gelatin nanospheres, which are further immobilized in the nanofibers of an injectable poly(l-lactic acid) (PLLA) microsphere. This hierarchical microsphere system not only protects the VEGF from denaturation and degradation, but also provides excellent control of its sustained release. In addition, the nanofibrous PLLA microsphere integrates the extracellular matrix-mimicking architecture with a highly porous injectable form, efficiently accommodating dental pulp stem cells (DPSCs) and supporting their proliferation and pulp tissue formation. Our in vivo study showed the successful regeneration of pulp-like tissues that fulfilled the entire apical and middle thirds and reached the coronal third of the full-length root canal. In addition, a large number of blood vessels were regenerated throughout the canal. For the first time, our work demonstrates the success of pulp tissue regeneration in a full-length root canal, making it a significant step toward regenerative endodontics. The regeneration of pulp tissues in a full-length tooth root canal has been one of the greatest challenges in the field of regenerative endodontics, and one of the biggest barriers for its clinical application. In this study, we developed a unique approach to tackle this challenge, and for the first time, we successfully regenerated living pulp tissues in a full-length root canal, making it a significant step toward regenerative endodontics. This study will make positive scientific

  6. Wheat root length and not branching is altered in the presence of neighbours, including blackgrass.

    Directory of Open Access Journals (Sweden)

    Jessica A Finch

    Full Text Available The effect of neighbouring plants on crop root system architecture may directly interfere with water and nutrient acquisition, yet this important and interesting aspect of competition remains poorly understood. Here, the effect of the weed blackgrass (Alopecurus myosuroides Huds. on wheat (Triticum aestivum L. roots was tested, since a low density of this species (25 plants m-2 can lead to a 10% decrease in wheat yield and herbicide resistance is problematic. We used a simplified growth system based on gelled medium, to grow wheat alongside a neighbour, either another wheat plant, a blackgrass or Brachypodium dystachion individual (a model grass. A detailed analysis of wheat seminal root system architecture showed that the presence of a neighbour principally affected the root length, rather than number or diameter under a high nutrient regime. In particular, the length of first order lateral roots decreased significantly in the presence of blackgrass and Brachypodium. However, this effect was not noted when wheat plants were grown in low nutrient conditions. This suggests that wheat may be less sensitive to the presence of blackgrass when grown in low nutrient conditions. In addition, nutrient availability to the neighbour did not modulate the neighbour effect on wheat root architecture.

  7. Wheat root length and not branching is altered in the presence of neighbours, including blackgrass

    Science.gov (United States)

    Finch, Jessica A.; Guillaume, Gaëtan; French, Stephanie A.; Colaço, Renato D. D. R.; Davies, Julia M.

    2017-01-01

    The effect of neighbouring plants on crop root system architecture may directly interfere with water and nutrient acquisition, yet this important and interesting aspect of competition remains poorly understood. Here, the effect of the weed blackgrass (Alopecurus myosuroides Huds.) on wheat (Triticum aestivum L.) roots was tested, since a low density of this species (25 plants m-2) can lead to a 10% decrease in wheat yield and herbicide resistance is problematic. We used a simplified growth system based on gelled medium, to grow wheat alongside a neighbour, either another wheat plant, a blackgrass or Brachypodium dystachion individual (a model grass). A detailed analysis of wheat seminal root system architecture showed that the presence of a neighbour principally affected the root length, rather than number or diameter under a high nutrient regime. In particular, the length of first order lateral roots decreased significantly in the presence of blackgrass and Brachypodium. However, this effect was not noted when wheat plants were grown in low nutrient conditions. This suggests that wheat may be less sensitive to the presence of blackgrass when grown in low nutrient conditions. In addition, nutrient availability to the neighbour did not modulate the neighbour effect on wheat root architecture. PMID:28542446

  8. Root length in the permanent teeth of women with an additional X chromosome (47,XXX females).

    Science.gov (United States)

    Lähdesmäki, Raija E; Alvesalo, Lassi J

    2010-07-01

    Previous studies have demonstrated differential effects of the X and Y chromosomes on dental development. The expression of sexual dimorphism in terms of tooth size, shape, number and developmental timing has been explained especially by Y chromosome influence. The Y chromosome promotes enamel, crown and root dentin development. The X chromosome has an effect on enamel deposition. The aim of this research is to study the influence of the extra X chromosome on the development of permanent tooth root length. The study subjects (all of whom were from the Kvantti Dental Research Project) were seven 47,XXX females, five female relatives and 51 and 52 population control men and women, respectively. Measurements were made from panoramic radiographs on available permanent teeth by a digital calliper according to established procedures. The results showed that the maxillary root lengths of the 47,XXX females were of the same magnitude as those in normal women, but the mandibular root lengths were longer in 47,XXX females than in normal men or women. Increased enamel thickness in the teeth of 47,XXX females is apparently caused by the active enamel gene in all X chromosomes having no increased influence on crown dentin formation. These results in 47,XXX females indicate an increase in root dentin development, at least in the mandible, which together with the data on crown formation reflects a continuous long-lasting effect of the X chromosome on dental development.

  9. Root length and alveolar bone level of impacted canines and adjacent teeth after orthodontic traction: a long-term evaluation

    Science.gov (United States)

    da SILVA, Aldir Cordeiro; CAPISTRANO, Anderson; de ALMEIDA-PEDRIN, Renata Rodrigues; CARDOSO, Maurício de Almeida; CONTI, Ana Cláudia de Castro Ferreira; CAPELOZZA, Leopoldino

    2017-01-01

    Abstract Objective The aim of this retrospective study was to evaluate the long-term effects of orthodontic traction on root length and alveolar bone level in impacted canines and adjacent teeth. Material and Methods Sample consisted of 16 patients (nine males and seven females), mean initial age 11 years and 8 months presenting with unilaterally maxillary impacted canines, palatally displaced, treated with the same surgical and orthodontic approach. Teeth from the impacted-canine side were assigned as Group I (GI), and contralateral teeth as control, Group II (GII). The mean age of patients at the end of orthodontic treatment was 14 years and 2 months and the mean post-treatment time was 5 years and 11 months. Both contralateral erupted maxillary canines and adjacent teeth served as control. Root length and alveolar bone level (buccal and palatal) were evaluated on cone-beam computed tomography (CBCT) images. The comparison of root length and alveolar bone level changes between groups were assessed by applying paired t-test, at a significance level of 5% (p<0.05). Results There were no statistically significant differences in root length and buccal and palatal bone levels of canines and adjacent teeth among groups. Conclusions Impacted canine treatment by closed-eruption technique associated with canine crown perforation, has a minimal effect on root length and buccal and palatal alveolar bone level in both canine and adjacent teeth, demonstrating that this treatment protocol has a good long-term prognosis. PMID:28198979

  10. The validity of cone-beam computed tomography in measuring root canal length using a gold standard

    NARCIS (Netherlands)

    Liang, Y.H.; Jiang, L.; Chen, C.; Gao, X.J.; Wesselink, P.R.; Wu, M.K.; Shemesh, H.

    2013-01-01

    Introduction The distance between a coronal reference point and the major apical foramen is important for working length determination. The aim of this in vitro study was to determine the accuracy of root canal length measurements performed with cone-beam computed tomographic (CBCT) scans using a

  11. The density and length of root hairs are enhanced in response to cadmium and arsenic by modulating gene expressions involved in fate determination and morphogenesis of root hairs in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Ramin Bahmani

    2016-11-01

    Full Text Available Root hairs are tubular outgrowths that originate from epidermal cells. Exposure of Arabidopsis to cadmium (Cd and arsenic [arsenite, As(III] increases root hair density and length. To examine the underlying mechanism, we measured the expression of genes involved in fate determination and morphogenesis of root hairs. Cd and As(III downregulated TTG1 and GL2 (negative regulators of fate determination and upregulated GEM (positive regulator, suggesting that root hair fate determination is stimulated by Cd and As(III. Cd and As(III increased the transcript levels of genes involved in root hair initiation (RHD6 and AXR2 and root hair elongation (AUX1, AXR1, ETR1, and EIN2 except CTR1. DR5::GUS transgenic Arabidopsis showed a higher DR5 expression in the root tip, suggesting that Cd and As(III increased the auxin content in the root tip. Knockdown of TTG1 in Arabidopsis resulted in increased root hair density and decreased root hair length compared with the control (Col-0 on 1/2 MS media. This phenotype may be attributed to the downregulation of GL2 and CTR1 and upregulation of RHD6. By contrast, gem mutant plants displayed a decrease in root hair density and length with reduced expression of RHD6, AXR2, AUX1, AXR1, ETR1, CTR1, and EIN2. Taken together, our results indicate that fate determination, initiation, and elongation of root hairs are stimulated in response to Cd and As(III through the modulation of the expression of genes involved in these processes in Arabidopsis.

  12. Morphological changes in cotton roots in relation to soil mechanical impedance and matric potential

    International Nuclear Information System (INIS)

    Nabi, G.; Mullins, C.E.

    2006-01-01

    Soil mechanical impedance (M1) and matric potential can both root growth rate, modify rooting pattern and root diameter. Cotton seedlings are sensitive to the soil physical environment, particularly during early stages of growth. Soil matric potential and M1 effect on root biomass, axial root length and diameter, and the number and length of lateral roots in soil packed to penetration resistances (PR) of 0.1, 1.0, 1.1 and 1.2 Mpa (mega Pascal 10/sup 6/ Pascal), each at three matric potentials of-10,-100 and -500 kpa (kilopascal ) = 10/sup 3/ Pascal), were determined. Total root length were reduced by 29, 50 and 53% at impedance of 1.0, 1.1 and 1.2 Mpa, respectively, as compared to the control, whereas M1 of 1.2 Mpa resulted in 60% reduction in axial root length. A similar increase in diameter was caused by increasing mechanical impedance, while decreasing matric potential had little effect. Roots that were water stressed did not change their diameter but had a shorter axis and longer lateral length. In contrast, the impeded roots (PR=1.0, 1.1 and 1.2 MPa) had both a shorter axis and a smaller total length, but had increased diameter. These results not only illustrate the plasticity of root response to stress but also demonstrate how the response differs between different types of stresses. (author)

  13. [Effects of sowing depth on seedling traits and root characteristics of summer maize].

    Science.gov (United States)

    Cao, Hui-ying; Wang, Ding-bo; Shi, Jian-guo; Zhu, Kun-lun; Dong, Shu-ting; Liu, Peng; Zhao, Bin; Zhang, Ji-wang

    2015-08-01

    Two summer maize hybrids, Zhengdan 958 (ZD958) and Xianyu 335 (XY335), were used as experimental materials. 4 sowing depths (3, 5, 7 and 9 cm) and uneven sowing depth (CK) were designed under sand culture and field experiments to investigate the effects of sowing depth on seedling traits and root characteristics of summer maize. The results showed that the seedling emergence rate gradually decreased and seedling emergence time gradually lengthened as the sowing depth increased. Compared with the sowing depth of 3 cm, the seedling emergence rates of ZD958 and XY335 sown at the depth of 9 cm were reduced by 9.4% and 11.8%, respectively, and the seedling emergence duration was prolonged 1.5 d. With the increasing sowing depth, the seedling length and uniformity decreased significantly, the mesocotyl length increased significantly, while the coleoptile length had no significant difference; the primary radicle length gradually decreased, the total length of secondary radicle gradually increased, and the total root length had no significant difference; the total dry mass of seedling and mesocotyl increased significantly, and the total root dry mass had no significant difference. With the increasing sowing depth, the soluble sugar content in each part of seedling increased and the amount of nutritional consumption of germinating seeds increased, the seedling root growth rate increased, but the root activity decreased, and the number of total nodal root and nodal layers increased. With the increasing sowing depth, harvested ears per unit area were reduced by decreased seedling emergence rate and seedling vigor, thus influenced the yield. In addition, uniform sowing depth could improve the canopy uniformity and relative characteristics, then increase the yield.

  14. Functional traits and root morphology of alpine plants.

    Science.gov (United States)

    Pohl, Mandy; Stroude, Raphaël; Buttler, Alexandre; Rixen, Christian

    2011-09-01

    Vegetation has long been recognized to protect the soil from erosion. Understanding species differences in root morphology and functional traits is an important step to assess which species and species mixtures may provide erosion control. Furthermore, extending classification of plant functional types towards root traits may be a useful procedure in understanding important root functions. In this study, pioneer data on traits of alpine plant species, i.e. plant height and shoot biomass, root depth, horizontal root spreading, root length, diameter, tensile strength, plant age and root biomass, from a disturbed site in the Swiss Alps are presented. The applicability of three classifications of plant functional types (PFTs), i.e. life form, growth form and root type, was examined for above- and below-ground plant traits. Plant traits differed considerably among species even of the same life form, e.g. in the case of total root length by more than two orders of magnitude. Within the same root diameter, species differed significantly in tensile strength: some species (Geum reptans and Luzula spicata) had roots more than twice as strong as those of other species. Species of different life forms provided different root functions (e.g. root depth and horizontal root spreading) that may be important for soil physical processes. All classifications of PFTs were helpful to categorize plant traits; however, the PFTs according to root type explained total root length far better than the other PFTs. The results of the study illustrate the remarkable differences between root traits of alpine plants, some of which cannot be assessed from simple morphological inspection, e.g. tensile strength. PFT classification based on root traits seems useful to categorize plant traits, even though some patterns are better explained at the individual species level.

  15. Construction Process of the Length of [cube root of 2] by Paper Folding

    Science.gov (United States)

    Guler, Hatice Kubra; Gurbuz, Mustafa Cagri

    2018-01-01

    The main purpose of this study is to investigate mathematics teachers' mathematical thinking process while they are constructing the length of [cube root of 2] by paper folding. To carry out this aim, two teachers--who are PhD. students--were interviewed one by one. During the construction, it was possible to observe the consolidation process of…

  16. Genetic variation in pea (Pisum sativum L.) demonstrates the importance of root but not shoot C/N ratios in the control of plant morphology and reveals a unique relationship between shoot length and nodulation intensity.

    Science.gov (United States)

    Ludidi, Ndiko N; Pellny, Till K; Kiddle, Guy; Dutilleul, Christelle; Groten, Karin; VAN Heerden, Philippus D R; Dutt, Som; Powers, Stephen J; Römer, Peter; Foyer, Christine H

    2007-10-01

    Nodule numbers are regulated through systemic auto-regulatory signals produced by shoots and roots. The relative effects of shoot and root genotype on nodule numbers together with relationships to organ biomass, carbon (C) and nitrogen (N) status, and related parameters were measured in pea (Pisum sativum) exploiting natural genetic variation in maturity and apparent nodulation intensity. Reciprocal grafting experiments between the early (Athos), intermediate (Phönix) and late (S00182) maturity phenotypes were performed and Pearson's correlation coefficients for the parameters were calculated. No significant correlations were found between shoot C/N ratios and plant morphology parameters, but the root C/N ratio showed a strong correlation with root fresh and dry weights as well as with shoot fresh weight with less significant interactions with leaf number. Hence, the root C/N ratio rather than shoot C/N had a predominant influence on plant morphology when pea plants are grown under conditions of symbiotic nitrogen supply. The only phenotypic characteristic that showed a statistically significant correlation with nodulation intensity was shoot length, which accounted for 68.5% of the variation. A strong linear relationship was demonstrated between shoot length and nodule numbers. Hence, pea nodule numbers are controlled by factors related to shoot extension, but not by shoot or root biomass accumulation, total C or total N. The relationship between shoot length and nodule numbers persisted under field conditions. These results suggest that stem height could be used as a breeding marker for the selection of pea cultivars with high nodule numbers and high seed N contents.

  17. Responses of grapevine rootstocks to drought through altered root system architecture and root transcriptomic regulations.

    Science.gov (United States)

    Yıldırım, Kubilay; Yağcı, Adem; Sucu, Seda; Tunç, Sümeyye

    2018-06-01

    Roots are the major interface between the plant and various stress factors in the soil environment. Alteration of root system architecture (RSA) (root length, spread, number and length of lateral roots) in response to environmental changes is known to be an important strategy for plant adaptation and productivity. In light of ongoing climate changes and global warming predictions, the breeding of drought-tolerant grapevine cultivars is becoming a crucial factor for developing a sustainable viticulture. Root-trait modeling of grapevine rootstock for drought stress scenarios, together with high-throughput phenotyping and genotyping techniques, may provide a valuable background for breeding studies in viticulture. Here, tree grafted grapevine rootstocks (110R, 5BB and 41B) having differential RSA regulations and drought tolerance were investigated to define their drought dependent root characteristics. Root area, root length, ramification and number of root tips reduced less in 110R grafted grapevines compared to 5BB and 41B grafted ones during drought treatment. Root relative water content as well as total carbohydrate and nitrogen content were found to be much higher in the roots of 110R than it was in the roots of other rootstocks under drought. Microarray-based root transcriptome profiling was also conducted on the roots of these rootstocks to identify their gene regulation network behind drought-dependent RSA alterations. Transcriptome analysis revealed totally 2795, 1196 and 1612 differentially expressed transcripts at the severe drought for the roots of 110R, 5BB and 41B, respectively. According to this transcriptomic data, effective root elongation and enlargement performance of 110R were suggested to depend on three transcriptomic regulations. First one is the drought-dependent induction in sugar and protein transporters genes (SWEET and NRT1/PTR) in the roots of 110R to facilitate carbohydrate and nitrogen accumulation. In the roots of the same rootstock

  18. [Spectrum-effect Relationship Between Total Antioxidant Activity and HPLC Fingerprint of Arctium lappa Root].

    Science.gov (United States)

    Wang, Xiao-juan; Jiang, Lin

    2014-12-01

    To explore the spectrum-effect relationship between the HPLC fingerprint of Arctium lappa root methanol extract and the total antioxidant activity. The experiment was carried out with Gemini C18 110A (250 mm x 4.6 mm, 5 µm) column using methanol-0.04% phosphoric acid as gradient mobile phase at the flow rate of 1.0 mL/min, detection wavelength of 320 nm. The total antioxidant activity was determined by measuring the absorbance of each sample after being reacted with ammonium molybdate reagent. The spectrum-effect relationship was investigated using canonical correlation analysis (CCA). The spectrum-effect relationship between the HPLC fingerprint of Arctium lappa root methanol extract and the total antioxidant activity were established, the similarity of fingerprint of all samples was above 0.9. Peaks 1, 6, 9, 12 and 14 were principle components of Arctium lappa root for the total antioxidant activity. This method contributes to the fast comprehensive evaluation of quality of Arctium lappa root.

  19. [Effects nutrients on the seedlings root hair development and root growth of Poncirus trifoliata under hydroponics condition].

    Science.gov (United States)

    Cao, Xiu; Xia, Ren-Xue; Zhang, De-Jian; Shu, Bo

    2013-06-01

    Ahydroponics experiment was conducted to study the effects of nutrients (N, P, K, Ca, Mg, Fe, and Mn) deficiency on the length of primary root, the number of lateral roots, and the root hair density, length, and diameter on the primary root and lateral roots of Poncirus trifoliata seedlings. Under the deficiency of each test nutrient, root hair could generate, but was mainly concentrated on the root base and fewer on the root tip. The root hair density on lateral roots was significantly larger than that on primary root, but the root hair length was in adverse. The deficiency of each test nutrient had greater effects on the growth and development of root hairs, with the root hair density on primary root varied from 55.0 to 174.3 mm(-2). As compared with the control, Ca deficiency induced the significant increase of root hair density and length on primary root, P deficiency promoted the root hair density and length on the base and middle part of primary root and on the lateral roots significantly, Fe deficiency increased the root hair density but decreased the root hair length on the tip of primary root significantly, K deficiency significantly decreased the root hair density, length, and diameter on primary root and lateral roots, whereas Mg deficiency increased the root hair length of primary root significantly. In all treatments of nutrient deficiency, the primary root had the similar growth rate, but, with the exceptions of N and Mg deficiency, the lateral roots exhibited shedding and regeneration.

  20. Total Factor Productivity Convergence in Africa: Panel Unit Root ...

    African Journals Online (AJOL)

    The study tested absolute and conditional convergence of Total Factor Productivity in Africa using a sample of 23 countries and TFP data covering the period between 1960 and 2003 while deploying the panel unit root methodology. Countries that have experienced sustained economic growth rate are found to have ...

  1. Effects of the Length of Stay on the Cost of Total Knee and Total Hip Arthroplasty from 2002 to 2013.

    Science.gov (United States)

    Molloy, Ilda B; Martin, Brook I; Moschetti, Wayne E; Jevsevar, David S

    2017-03-01

    Utilization of total knee and hip arthroplasty has greatly increased in the past decade in the United States; these are among the most expensive procedures in patients with Medicare. Advances in surgical techniques, anesthesia, and care pathways decrease hospital length of stay. We examined how trends in hospital cost were altered by decreases in length of stay. Procedure, demographic, and economic data were collected on 6.4 million admissions for total knee arthroplasty and 2.8 million admissions for total hip arthroplasty from 2002 to 2013 using the National (Nationwide) Inpatient Sample, a component of the Healthcare Cost and Utilization Project. Trends in mean hospital costs and their association with length of stay were estimated using inflation-adjusted, survey-weighted generalized linear regression models, controlling for patient demographic characteristics and comorbidity. From 2002 to 2013, the length of stay decreased from a mean time of 4.06 to 2.97 days for total knee arthroplasty and from 4.06 to 2.75 days for total hip arthroplasty. During the same time period, the mean hospital cost for total knee arthroplasty increased from $14,988 (95% confidence interval [CI], $14,927 to $15,049) in 2002 to $22,837 (95% CI, $22,765 to $22,910) in 2013 (an overall increase of $7,849 or 52.4%). The mean hospital cost for total hip arthroplasty increased from $15,792 (95% CI, $15,706 to $15,878) in 2002 to $23,650 (95% CI, $23,544 to $23,755) in 2013 (an increase of $7,858 or 49.8%). If length of stay were set at the 2002 mean, the growth in cost for total knee arthroplasty would have been 70.8% instead of 52.4% as observed, and the growth in cost for total hip arthroplasty would have been 67.4% instead of 49.8% as observed. Hospital costs for joint replacement increased from 2002 to 2013, but were attenuated by reducing inpatient length of stay. With demographic characteristics showing an upward trend in the utilization of joint arthroplasty, including a shift

  2. Root Characteristics of Perennial Warm-Season Grasslands Managed for Grazing and Biomass Production

    Directory of Open Access Journals (Sweden)

    Rattan Lal

    2013-07-01

    Full Text Available Minirhizotrons were used to study root growth characteristics in recently established fields dominated by perennial C4-grasses that were managed either for cattle grazing or biomass production for bioenergy in Virginia, USA. Measurements over a 13-month period showed that grazing resulted in smaller total root volumes and root diameters. Under biomass management, root volume was 40% higher (49 vs. 35 mm3 and diameters were 20% larger (0.29 vs. 0.24 mm compared to grazing. While total root length did not differ between grazed and biomass treatments, root distribution was shallower under grazed areas, with 50% of total root length in the top 7 cm of soil, compared to 41% in ungrazed exclosures. These changes (i.e., longer roots and greater root volume in the top 10 cm of soil under grazing but the reverse at 17–28 cm soil depths were likely caused by a shift in plant species composition as grazing reduced C4 grass biomass and allowed invasion of annual unsown species. The data suggest that management of perennial C4 grasslands for either grazing or biomass production can affect root growth in different ways and this, in turn, may have implications for the subsequent carbon sequestration potential of these grasslands.

  3. Effects of Hurricane-Felled Tree Trunks on Soil Carbon, Nitrogen, Microbial Biomass, and Root Length in a Wet Tropical Forest

    Directory of Open Access Journals (Sweden)

    D. Jean Lodge

    2016-11-01

    Full Text Available Decaying coarse woody debris can affect the underlying soil either by augmenting nutrients that can be exploited by tree roots, or by diminishing nutrient availability through stimulation of microbial nutrient immobilization. We analyzed C, N, microbial biomass C and root length in closely paired soil samples taken under versus 20–50 cm away from large trunks of two species felled by Hugo (1989 and Georges (1998 three times during wet and dry seasons over the two years following the study conducted by Georges. Soil microbial biomass, % C and % N were significantly higher under than away from logs felled by both hurricanes (i.e., 1989 and 1998, at all sampling times and at both depths (0–10 and 10–20 cm. Frass from wood boring beetles may contribute to early effects. Root length was greater away from logs during the dry season, and under logs in the wet season. Root length was correlated with microbial biomass C, soil N and soil moisture (R = 0.36, 0.18, and 0.27, respectively; all p values < 0.05. Microbial biomass C varied significantly among seasons but differences between positions (under vs. away were only suggestive. Microbial C was correlated with soil N (R = 0.35. Surface soil on the upslope side of the logs had significantly more N and microbial biomass, likely from accumulation of leaf litter above the logs on steep slopes. We conclude that decaying wood can provide ephemeral resources that are exploited by tree roots during some seasons.

  4. Changes of Root Length and Root-to-Crown Ratio after Apical Surgery

    DEFF Research Database (Denmark)

    von Arx, Thomas; Jensen, Simon S; Bornstein, Michael M

    2015-01-01

    INTRODUCTION: Apical surgery is an important treatment option for teeth with post-treatment periodontitis. Although apical surgery involves root-end resection, no morphometric data are yet available about root-end resection and its impact on the root-to-crown ratio (RCR). The present study assess...

  5. COMPRIMENTO DA ESTACA DE RAMO NO ENRAIZAMENTO DE GINSENG BRASILEIRO (Pfaffia glomerata SHOOT CUTTING LENGTH ON ROOTING OF BRAZILIAN GINSENG (Pfaffia glomerata

    Directory of Open Access Journals (Sweden)

    Fernando Teixeira Nicoloso

    2001-02-01

    Full Text Available A Pfaffia glomerata (Spreng. Pedersen é uma dentre várias espécies conhecidas como ginseng brasileiro e é usada como planta medicinal. O objetivo desse trabalho foi determinar se o comprimento da estaca de ramo influencia o enraizamento da P. glomerata. Os tratamentos usados consistiram de três comprimentos de estacas (10, 15 e 20cm; ± 1cm de variação. As estacas foram obtidas dos 70cm basais de ramos, com 80 a 140cm de comprimento, de plantas possuindo dois anos de idade, cultivadas no Jardim Botânico da UFSM. Utilizou-se o delineamento experimental de blocos ao acaso com três repetições e 30 estacas por unidade experimental. O bloco experimental consistiu de uma bandeja plástica com capacidade para 36 litros de solução nutritiva. O experimento foi instalado no dia 15 de julho de 1998 e conduzido por 44 dias sob condições controladas de temperatura, luminosidade e umidade do ar. Os resultados indicaram que (i o tamanho da estaca não afeta a percentagem de enraizamento, a produção de massa seca de folhas e raízes. Por outro lado, as mudas obtidas de estacas de 10cm apresentam maior número de brotações, comprimento das brotações, massa seca de talos e massa seca total produzida por estaca que as de 20cm; e (ii o uso de estacas com 10cm de comprimento é viável e, conseqüentemente, possibilita a obtenção de um maior número de estacas por ramo.Pfaffia glomerata (Spreng. Pedersen is among several species known as Brazilian ginsengs and it is used as medicinal plant. The aim of this work was to evaluate the length of the shoot cuttings on rooting of P. glomerata. Treatments consisted of three length of cuttings (10, 15, and 20cm; ± 1cm of variation. Cuttings were obtained from the 70cm of the basal portion from shoots of 80 to 140cm of length, from two-year-old plants grown in the Botanical Garden at State University of Santa Maria, RS, Brazil. Treatments were distributed in a completely randomized block design with

  6. Reducing Length of Stay in Total Joint Arthroplasty Care.

    Science.gov (United States)

    Walters, Megan; Chambers, Monique C; Sayeed, Zain; Anoushiravani, Afshin A; El-Othmani, Mouhanad M; Saleh, Khaled J

    2016-10-01

    As health care reforms continue to improve quality of care, significant emphasis will be placed on evaluation of orthopedic patient outcomes. Total joint arthroplasty (TJA) has a proven track record of enhancing patient quality of life and are easily replicable. The outcomes of these procedures serve as a measure of health care initiative success. Specifically, length of stay, will be targeted as a marker of quality of surgical care delivered to TJA patients. Within this review, we will discuss preoperative and postoperative methods by which orthopedic surgeons may enhance TJA outcomes and effectively reduce length of stay. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Genetic association among root morphology, root quality and root yield in ashwagandha (Withania somnifera)

    OpenAIRE

    Kumar Ramesh R.; Reddy Anjaneya Prasanna L.; Subbaiah Chinna J.; Kumar Niranjana A.; Prasad Nagendra H.N.; Bhukya Balakishan

    2011-01-01

    Ashwagandha (Withania somnifera) is a dryland medicinal crop and roots are used as valuable drug in traditional systems of medicine. Morphological variants (morphotypes) and the parental populations were evaluated for root - morphometric, quality and yield traits to study genetic association among them. Root morphometric traits (root length, root diameter, number of secondary roots/ plant) and crude fiber content exhibited strong association among them and ...

  8. Total Path Length and Number of Terminal Nodes for Decision Trees

    KAUST Repository

    Hussain, Shahid

    2014-09-13

    This paper presents a new tool for study of relationships between total path length (average depth) and number of terminal nodes for decision trees. These relationships are important from the point of view of optimization of decision trees. In this particular case of total path length and number of terminal nodes, the relationships between these two cost functions are closely related with space-time trade-off. In addition to algorithm to compute the relationships, the paper also presents results of experiments with datasets from UCI ML Repository1. These experiments show how two cost functions behave for a given decision table and the resulting plots show the Pareto frontier or Pareto set of optimal points. Furthermore, in some cases this Pareto frontier is a singleton showing the total optimality of decision trees for the given decision table.

  9. Root length, biomass, tissue chemistry and mycorrhizal colonization following 14 years of CO2 enrichment and 6 years of N fertilization in a warm temperate forest.

    Science.gov (United States)

    Taylor, Benton N; Strand, Allan E; Cooper, Emily R; Beidler, Katilyn V; Schönholz, Marcos; Pritchard, Seth G

    2014-09-01

    Root systems serve important roles in carbon (C) storage and resource acquisition required for the increased photosynthesis expected in CO2-enriched atmospheres. For these reasons, understanding the changes in size, distribution and tissue chemistry of roots is central to predicting the ability of forests to capture anthropogenic CO2. We sampled 8000 cm(3) soil monoliths in a pine forest exposed to 14 years of free-air-CO2-enrichment and 6 years of nitrogen (N) fertilization to determine changes in root length, biomass, tissue C : N and mycorrhizal colonization. CO2 fumigation led to greater root length (98%) in unfertilized plots, but root biomass increases under elevated CO2 were only found for roots biomass in N-fertilized plots (19%), but fine root [N] and [C] both increased under N fertilization (29 and 2%, respectively). Mycorrhizal root tip biomass responded positively to CO2 fumigation in unfertilized plots, but was unaffected by CO2 under N fertilization. Changes in fine root [N] and [C] call for further study of the effects of N fertilization on fine root function. Here, we show that the stimulation of pine roots by elevated CO2 persisted after 14 years of fumigation, and that trees did not rely exclusively on increased mycorrhizal associations to acquire greater amounts of required N in CO2-enriched plots. Stimulation of root systems by CO2 enrichment was seen primarily for fine root length rather than biomass. This observation indicates that studies measuring only biomass might overlook shifts in root systems that better reflect treatment effects on the potential for soil resource uptake. These results suggest an increase in fine root exploration as a primary means for acquiring additional soil resources under elevated CO2. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Apical root resorption during orthodontic treatment with aligners? A retrospective radiometric study.

    Science.gov (United States)

    Krieger, Elena; Drechsler, Thomas; Schmidtmann, Irene; Jacobs, Collin; Haag, Simeon; Wehrbein, Heinrich

    2013-08-14

    Objective of this study was to investigate the incidence and severity of apical root resorptions (ARR) during orthodontic treatment with aligners. The sample comprised 100 patients (17-75 years of age) with a class I occlusion and anterior crowding before treatment, treated exclusively with aligners (Invisalign®, Align Technologies, Santa Clara, CA, USA). The following teeth were assessed: upper and lower anterior teeth and first molars. Root and crown lengths of a total of 1600 teeth were measured twice in pre- and post-treatment panoramic radiographs. Afterwards, relative changes of the root length during treatment were calculated by a root-crown-ratio taking pre- and post-treatment root and crown lengths into consideration. A reduction of this ratio was considered as a shortening of the initial root length. Additionally, tooth movements of the front teeth were assessed by lateral cephalograms and the 3-dimensonal set up of each patient. All patients had a reduction of the pre-treatment root length with a minimum of two teeth. On average 7.36 teeth per patient were affected. 54% of 1600 measured teeth showed no measurable root reduction. A reduction of >0%-10% of the pre-treatment root length was found in 27.75%, a distinct reduction of >10%-20% in 11.94%. 6.31% of all teeth were affected with a considerable reduction of >20%. We found no statistically significant correlation between relative root length changes and the individual tooth, gender, age or sagittal and vertical orthodontic tooth movement; except for extrusion of upper front teeth, which was considered as not clinical relevant due to the small amount of mean 4% ARR. The present study is the first analyzing ARR in patients with a fully implemented orthodontic treatment with aligners (i.e. resolving anterior crowding). The variety was high and no clinical relevant influence factor could be detected. A minimum of two teeth with a root length reduction was found in every patient. On average, 7.36 teeth

  11. Rooting depth and root depth distribution of Trifolium repens × T. uniflorum interspecific hybrids.

    Science.gov (United States)

    Nichols, S N; Hofmann, R W; Williams, W M; van Koten, C

    2016-05-20

    Traits related to root depth distribution were examined in Trifolium repens × T. uniflorum backcross 1 (BC 1 ) hybrids to determine whether root characteristics of white clover could be improved by interspecific hybridization. Two white clover cultivars, two T. uniflorum accessions and two BC 1 populations were grown in 1 -m deep tubes of sand culture. Maximum rooting depth and root mass distribution were measured at four harvests over time, and root distribution data were fitted with a regression model to provide measures of root system shape. Morphological traits were measured at two depths at harvest 3. Root system shape of the hybrids was more similar to T. uniflorum than to white clover. The hybrids and T. uniflorum had a higher rate of decrease in root mass with depth than white clover, which would result in higher proportions of root mass in the upper profile. Percentage total root mass at 100-200 mm depth was higher for T. uniflorum than white clover, and for Crusader BC 1 than 'Crusader'. Roots of the hybrids and T. uniflorum also penetrated deeper than those of white clover. T. uniflorum had thicker roots at 50-100 mm deep than the other entries, and more of its fine root mass at 400-500 mm. The hybrids and white clover had more of their fine root mass higher in the profile. Consequently, T. uniflorum had a higher root length density at 400-500 mm than most entries, and a smaller decrease in root length density with depth. These results demonstrate that rooting characteristics of white clover can be altered by hybridization with T. uniflorum, potentially improving water and nutrient acquisition and drought resistance. Root traits of T. uniflorum are likely to be adaptations to soil moisture and fertility in its natural environment. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Root resorption of permanent incisors during three months of active orthodontic treatment.

    Science.gov (United States)

    Batool, Iffat; Abbas, Hasnain; Abbas, Assad; Abbas, Iram

    2010-01-01

    Root resorption is one of the most common and undesirable sequelea of orthodontic treatment. The aim of this study was to evaluate the amount of root resorption in permanent incisors during 3 month active period of fixed orthodontic appliance therapy using periapical radiographs. Periapical radiographs of a total of 138 permanent teeth (n = 138, mandibular n1 = 52, maxillary n2 = 86) were evaluated for root resorption. All patients were treated with 3M MBT multi-bonded, pre-adjusted appliances with 0.022 inch slots. Initial levelling and alignment was achieved with 0.0175 inch co-axial wires. All four incisors (maxillary and mandibular) were measured for any change in root length. The change in root length between T0 (pre-treatment) and T1 (post-treatment) was measured in millimetres and expressed in terms of percentage of original root length. The mean pre treatment (T0) root length for the maxillary teeth (n1 = 62) was 19.27 +/- 2.86 mm and 20.01 +/- 2.57 mm for the mandibular teeth (n2 = 31). The post-treatment (T1) root length for the maxillary teeth was 18.96 +/- 2.85 mm and 19.49 +/- 2.4 mm for the mandibular teeth showing a mean resorption of 0.31 mm and 0.52 mm for the maxillary and mandibular teeth respectively. Root resorption was strongly correlated with active orthodontic appliance therapy with maxillary and mandibular incisors being most susceptible. It was found that root resorption can be detected even in the early levelling and alignment stages of orthodontic treatment.

  13. Soil aggregation and slope stability related to soil density, root length, and mycorrhiza

    Science.gov (United States)

    Graf, Frank; Frei, Martin

    2013-04-01

    Eco-engineering measures combine the use of living plants and inert mechanical constructions to protect slopes against erosion and shallow mass movement. Whereas in geotechnical engineering several performance standards and guidelines for structural safety and serviceability of construction exist, there is a lack of comparable tools in the field of ecological restoration. Various indicators have been proposed, including the fractal dimension of soil particle size distribution, microbiological parameters, and soil aggregate stability. We present results of an soil aggregate stability investigation and compare them with literature data of the angle of internal friction ?' which is conventionally used in slope stability analysis and soil failure calculation. Aggregate stability tests were performed with samples of differently treated moraine, including soil at low (~15.5 kN/m³) and high (~19.0 kN/m³) dry unit weight, soil planted with Alnus incana (White Alder) as well as the combination of soil planted with alder and inoculated with the mycorrhizal fungus Melanogaster variegatus s.l. After a 20 weeks growth period in a greenhouse, a total of 100 samples was tested and evaluated. Positive correlations were found between the soil aggregate stability and the three variables dry unit weight, root length per soil volume, and degree of mycorrhization. Based on robust statistics it turned out that dry unit weight and mycorrhization degree were strongest correlated with soil aggregate stability. Compared to the non-inoculated control plants, mycorrhized White Alder produced significantly more roots and higher soil aggregate stability. Furthermore, the combined biological effect of plant roots and mycorrhizal mycelia on aggregate stability on soil with low density (~15.5 kN/m³) was comparable to the compaction effect of the pure soil from 15.5 to ~19.0 kN/m³. Literature data on the effect of vegetation on the angle of internal friction ?' of the same moraine showed

  14. Direct and indirect effects of glomalin, mycorrhizal hyphae, and roots on aggregate stability in rhizosphere of trifoliate orange.

    Science.gov (United States)

    Wu, Qiang-Sheng; Cao, Ming-Qin; Zou, Ying-Ning; He, Xin-hua

    2014-07-25

    To test direct and indirect effects of glomalin, mycorrhizal hyphae, and roots on aggregate stability, perspex pots separated by 37-μm nylon mesh in the middle were used to form root-free hyphae and root/hyphae chambers, where trifoliate orange (Poncirus trifoliata) seedlings were colonized by Funneliformis mosseae or Paraglomus occultum in the root/hyphae chamber. Both fungal species induced significantly higher plant growth, root total length, easily-extractable glomalin-related soil protein (EE-GRSP) and total GRSP (T-GRSP), and mean weight diameter (an aggregate stability indicator). The Pearson correlation showed that root colonization or soil hyphal length significantly positively correlated with EE-GRSP, difficultly-extractable GRSP (DE-GRSP), T-GRSP, and water-stable aggregates in 2.00-4.00, 0.50-1.00, and 0.25-0.50 mm size fractions. The path analysis indicated that in the root/hyphae chamber, aggregate stability derived from a direct effect of root colonization, EE-GRSP or DE-GRSP. Meanwhile, the direct effect was stronger by EE-GRSP or DE-GRSP than by mycorrhizal colonization. In the root-free hyphae chamber, mycorrhizal-mediated aggregate stability was due to total effect but not direct effect of soil hyphal length, EE-GRSP and T-GRSP. Our results suggest that GRSP among these tested factors may be the primary contributor to aggregate stability in the citrus rhizosphere.

  15. Phenotyping Root System Architecture of Cotton (Gossypium barbadense L. Grown Under Salinity

    Directory of Open Access Journals (Sweden)

    Mottaleb Shady A.

    2017-12-01

    Full Text Available Soil salinity causes an annual deep negative impact to the global agricultural economy. In this study, the effects of salinity on early seedling physiology of two Egyptian cotton (Gossypium barbadense L. cultivars differing in their salinity tolerance were examined. Also the potential use of a low cost mini-rhizotron system to measure variation in root system architecture (RSA traits existing in both cultivars was assessed. Salt tolerant cotton cultivar ‘Giza 90’ produced significantly higher root and shoot biomass, accumulated lower Na+/K+ ratio through a higher Na+ exclusion from both roots and leaves as well as synthesized higher proline contents compared to salt sensitive ‘Giza 45’ cultivar. Measuring RSA in mini-rhizotrons containing solid MS nutrient medium as substrate proved to be more precise and efficient than peat moss/sand mixture. We report superior values of main root growth rate, total root system size, main root length, higher number of lateral roots and average lateral root length in ‘Giza 90’ under salinity. Higher lateral root density and length together with higher root tissue tolerance of Na+ ions in ‘Giza 90’ give it an advantage to be used as donor genotype for desirable root traits to other elite cultivars.

  16. Morphology and biomass variations in root system of young tomato plants (Solanum sp.)

    International Nuclear Information System (INIS)

    Álvarez Gil, Marta A.; Fernández, Ana Fita; Ruiz Sánchez, María del C.; Bolarín Jiménez, María del C.

    2016-01-01

    The scarce exploitation of genotypic variability present in plant roots is an attractive breeding choice with regard to abiotic stresses and supports the objective of this work, which is to identify genotypic variation in root system traits of tomato genotypes (Solanum sp.). Thus, five tomato genotypes were studied: the commercial hybrid cultivar Jaguar (S. lycopersicum), Pera, Volgogradiskij and PE-47 entry (S. pennellii), which were collected in Peru, and the interspecific hybrid PeraxPE-47. Plants were grown in hydroponics for 26 days since germination; their roots were extracted and images were digitalized on scanner to evaluate total length, average diameter, the projected area and root length, following the categories per diameter of the whole root system through software Win Rhizo Pro 2003. The dry mass of roots and aerial parts was also recorded. Results indicated that genotypes differed in morphology, length according to diameter, root system spatial configuration and biomass, mainly with respect to the wild salinity resistant species PE-47. The interspecific hybrid PxPE-47 could be used as a rootstock to increase salt tolerance of susceptible cultivars. (author)

  17. Root canal shaping using rotary nickel-titanium files in preclinical dental education in Turkey.

    Science.gov (United States)

    Ünal, Gül Çelik; Maden, Murat; Orhan, Ekim Onur; Sarıtekin, Erdal; Teke, Anıl

    2012-04-01

    The purposes of this study were to evaluate the ability of a group of third-year dental students without any endodontic clinical experience to use the ProTaper Instruments (Dentsply Maillefer) to decrease the amount of straightening of curved canals on human molar teeth and to determine the incidence of instrument fractures and instrumentation time. Thirty-one undergraduate dental students in Turkey received a training session. The students prepared a total of 144 root canals in human mandibular or maxillary molar teeth with ProTaper. Fifty-six teeth were excluded due to unreadable image, misinformation, or straight or severe curve. Using pre- and post-preparation digital radiographs, the straightening of curved root canals was investigated. Loss of working length and incidence of fracture were also noted. A total of eighty-eight curved root canals were selected. Mesiobuccal or mesiolingual roots with curvatures of between 20° and 43° as assessed by Schneider's method and working length of between 15 mm and 22.5 mm were included in the study. The means of the curved root canals before and after the instrumentation were 29.5° ± 6° and 27° ± 6.3°, respectively. The means of the working length before and after the instrumentation were 19 mm ± 2.1 mm and 18.3 mm ± 1.9 mm, respectively. A statistically significant difference between straightening of curved root canals and loss of working length was found between before and after instrumentation (psession.

  18. Micro-computed Tomographic Analysis of Apical Microcracks before and after Root Canal Preparation by Hand, Rotary, and Reciprocating Instruments at Different Working Lengths.

    Science.gov (United States)

    de Oliveira, Bruna Paloma; Câmara, Andréa Cruz; Duarte, Daniel Amancio; Heck, Richard John; Antonino, Antonio Celso Dantas; Aguiar, Carlos Menezes

    2017-07-01

    This study aimed to compare apical microcrack formation after root canal shaping by hand, rotary, and reciprocating files at different working lengths using micro-computed tomographic analysis. Sixty mandibular incisors were randomly divided into 6 experimental groups (n = 10) according to the systems and working lengths used for the root canal preparation: ProTaper Universal for Hand Use (Dentsply Maillefer, Ballaigues, Switzerland), HyFlex CM (Coltene-Whaledent, Allstetten, Switzerland), and Reciproc (VDW, Munich, Germany) files working at the apical foramen (AF) and 1 mm short of the AF (AF - 1 mm). The teeth were imaged with micro-computed tomographic scanning at an isotropic resolution of 14 μm before and after root canal preparation, and the cross-sectional images generated were assessed to detect microcracks in the apical portion of the roots. Overall, 17 (28.3%) specimens presented microcracks before instrumentation. Apical microcracks were present in 1 (ProTaper Universal for Hand Use), 3 (Hyflex CM), and 2 (Reciproc) specimens when the instrumentation terminated at the AF. When instrumentation was terminated at AF - 1 mm, apical microcracks were detected in 3 (ProTaper Universal for Hand Use) and 4 (Hyflex CM and Reciproc) specimens. All these microcracks detected after root canal preparation were already present before instrumentation, and no new apical microcrack was visualized. For all groups, the number of slices presenting microcracks after root canal preparation was the same as before canal preparation. Root canal shaping with ProTaper Universal for Hand Use, HyFlex CM, and Reciproc systems, regardless of the working length, did not produce apical microcracks. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. Proportion of root-derived acid phosphomonoesterase in total soil acid phosphomonoesterase in different forests

    Directory of Open Access Journals (Sweden)

    Ladislav Holík

    2011-01-01

    Full Text Available Enzyme acid phosphomonoesterase (APM plays an important role in phosphorus mineralization in different type of terrestrial ecosystems. This enzyme is of great agronomic significance because it hydrolyses organic phosphorus to different forms of inorganic phosphorus which are assimilable by plants. APM may also indicate changes in the quantity and quality of phosphorylated substrates in soil and is a good indicator of its biological state as well as presence of pollutants. APM may be produced by plant roots and soil microorganisms and both of these sources may play different role in phosphorus mineralization in different ecosystems. The aim of this work was determine acid phosphomonoesterase (APM activity location in soil of different forest ecosystems. The APM activity location determination was performed on the basis of root-derived and soil-derived APM and expression of proportion of those root-derived in total soil APM up to 13 cm depth. The results of this preliminary study showed that root-derived APM formed 21–34 % of total soil APM in pine and oak forest.

  20. Development of fine and coarse roots of Thuja occidentalis 'Brabant' in non-irrigated and drip irrigated field plots

    NARCIS (Netherlands)

    Pronk, A.A.; Willigen, de P.; Heuvelink, E.; Challa, H.

    2002-01-01

    Aboveground dry mass, total root dry mass and root length density of the fine roots of Thuja occidentalis `Brabant' were determined under non- and drip-irrigated field conditions. Two-dimensional diffusion parameters for dynamic root growth were estimated based on dry mass production of the fine

  1. effects of different concentrations of auxins on rooting and root

    African Journals Online (AJOL)

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    ABSTRACT: The effect of auxins and their different concentrations on rooting and root ... primary root length and the longest primary root was recorded with the ... ceuticals, lubricants, foods, electrical insulators, .... stem cuttings of jojoba treated with IBA and NAA, .... increasing cell division and enlargement at each.

  2. Characterization of Root and Shoot Traits in Wheat Cultivars with Putative Differences in Root System Size

    Directory of Open Access Journals (Sweden)

    Victoria Figueroa-Bustos

    2018-07-01

    Full Text Available Root system size is a key trait for improving water and nitrogen uptake efficiency in wheat (Triticum aestivum L.. This study aimed (i to characterize the root system and shoot traits of five wheat cultivars with apparent differences in root system size; (ii to evaluate whether the apparent differences in root system size observed at early vegetative stages in a previous semi-hydroponic phenotyping experiment are reflected at later phenological stages in plants grown in soil using large rhizoboxes. The five wheat cultivars were grown in a glasshouse in rhizoboxes filled to 1.0 m with field soil. Phenology and shoot traits were measured and root growth and proliferation were mapped to quantify root length density (RLD, root length per plant, root biomass and specific root length (SRL. Wheat cultivars with large root systems had greater root length, more root biomass and thicker roots, particularly in the top 40 cm, than those with small root systems. Cultivars that reached anthesis later had larger root system sizes than those that reached anthesis earlier. Later anthesis allowed more time for root growth and proliferation. Cultivars with large root systems had 25% more leaf area and biomass than those with small root systems, which presumably reflects high canopy photosynthesis to supply the demand for carbon assimilates to roots. Wheat cultivars with contrasting root system sizes at the onset of tillering (Z2.1 in a semi-hydroponic phenotyping system maintained their size ranking at booting (Z4.5 when grown in soil. Phenology, particularly time to anthesis, was associated with root system size.

  3. Genotypic diversity of root and shoot characteristics of

    Directory of Open Access Journals (Sweden)

    ali ganjali

    2009-06-01

    Full Text Available Root and shoot characteristics of chickpea (Cicer arietinum L. genotypes are believed to be important in drought tolerance. There is a little information about the response of genotypes root growth in hydroponics and greenhouse culture, also the relationships between root size and drought tolerance. This study was conducted to observe whether genotypes differ in root size, and to see that root size is associated with drought tolerance during early vegetative growth. We found significant differences (p0.01 in root dry weight, total root length, tap root length, root area, leaf dry weight, leaf area and shoot biomass per plant among 30 genotypes of chickpea grown in hydroponics culture for three weeks. Each of these parameters correlated with all others, positively. Among 30 genotypes, 10 genotypes with different root sizes were selected and were grown in a greenhouse in sand culture experiment under drought stress (FC %30 for three weeks. There were not linear or non-linear significant correlations between root characters in hydroponics and greenhouse environments. It seems that environmental factors are dominant on genetic factors in seedling stage and so, the expression of genotypics potential for root growth characteristics of genotypes are different in hydroponic and greenhouse conditions. In this study, the selection of genotypes with vigorous roots system in hydroponic condition did not lead to genotypes with the same root characters in greenhouse environment. The genotype×drought interactions for root characters of chickpea seedlings in 30 days were not significant (p

  4. Influence of plant root morphology and tissue composition on phenanthrene uptake: Stepwise multiple linear regression analysis

    International Nuclear Information System (INIS)

    Zhan, Xinhua; Liang, Xiao; Xu, Guohua; Zhou, Lixiang

    2013-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are contaminants that reside mainly in surface soils. Dietary intake of plant-based foods can make a major contribution to total PAH exposure. Little information is available on the relationship between root morphology and plant uptake of PAHs. An understanding of plant root morphologic and compositional factors that affect root uptake of contaminants is important and can inform both agricultural (chemical contamination of crops) and engineering (phytoremediation) applications. Five crop plant species are grown hydroponically in solutions containing the PAH phenanthrene. Measurements are taken for 1) phenanthrene uptake, 2) root morphology – specific surface area, volume, surface area, tip number and total root length and 3) root tissue composition – water, lipid, protein and carbohydrate content. These factors are compared through Pearson's correlation and multiple linear regression analysis. The major factors which promote phenanthrene uptake are specific surface area and lipid content. -- Highlights: •There is no correlation between phenanthrene uptake and total root length, and water. •Specific surface area and lipid are the most crucial factors for phenanthrene uptake. •The contribution of specific surface area is greater than that of lipid. -- The contribution of specific surface area is greater than that of lipid in the two most important root morphological and compositional factors affecting phenanthrene uptake

  5. Total Path Length and Number of Terminal Nodes for Decision Trees

    KAUST Repository

    Hussain, Shahid

    2014-01-01

    This paper presents a new tool for study of relationships between total path length (average depth) and number of terminal nodes for decision trees. These relationships are important from the point of view of optimization of decision trees

  6. Relationships between soluble sugar concentrations in roots and ecosystem stress for first-year sugar maple seedlings

    Energy Technology Data Exchange (ETDEWEB)

    McLaughlin, J.W.; Reed, D.D.; Jurgensen, M.F.; Mroz, G.D.; Bagley, S.T. [Michigan Technological University, Houghton, MI (United States). School of Forestry and Wood Products

    1996-03-01

    Accumulation of reducing sugars (i.e. glucose and fructose) in plant roots has been consistently correlated with forest dieback and decline and, therefore, has potential as a biological indicator of ecosystem stress. In this study, the relationships between acidic deposition and `natural` (temperature, mycorrhizae, and nutrition) factors with first-year sugar maple seedling root sugar concentrations and growth were assessed in two sugar maple dominated forests in Michigan. Seedlings at the southern site (Wellston) had greater root growth, phosphorus, total sugar, and sucrose concentrations in roots, but lower reducing sugar concentration in roots. In addition, percent root length colonized by vesicular-arbuscular mycorrhizal fungi was less than that found for seedlings growing at the northern site (Alberta). Throughfall deposition of nitrate, sulfate, and hydrogen ions was not significantly correlated with seedling total or reducing sugar concentration. Total sugar concentration in seedling roots was positively correlated with air and soil temperatures at the southern site, but not at the northern site. Seedling tissue phosphorus concentration was correlated with total sugars at both sites, with sucrose at the southern site, and reducing sugars at the northern site. Mycorrhizal colonization rates at the Alberta site were positively correlated with reducing sugar concentration in seedling roots and negatively correlated with sucrose concentration. The results suggest that differences in seedling root sugar concentrations in these two forests are related to seedling root growth and are most likely due to ecological variables, such as available soil phosphorus, temperature, and growing season length through some complex interaction with mycorrhizae rather than acidic deposition stress. 56 refs., 3 figs.

  7. Shortened of the crown and root lengths of the mandibular permanent molar in beta major thalassemia children

    Directory of Open Access Journals (Sweden)

    Indra Primathena

    2011-07-01

    Full Text Available Beta major thalassemia is a genetically inherited blood disorder due to a genetic mutation on the polypeptide chains of hemoglobin which is manifested in the growth and development of the tooth. The objectives of the investigation were to obtain differences of the crown and root lengths of the mandibular first right side permanent molar between beta major thalassemia children and normal children group at the matching ages of 11 to 13 years old. The descriptive comparative method was used in the study and samples were selected using the purposive sampling technique. Sample numbers, which were obtained using the consecutive sampling technique, consists of 12 children of beta major thalassemia and 12 of normal children at the matching ages of 11 to 13 years. Periapical radiographs of both thalassemia and normal children were administered using the method of Seow and Lai. Data were analyzed using t-test method. The study revealed that the crown and root lengths of the mandibular first right side permanent molar of beta major thalassemia children were shorter than normal children at the ages of 11 to 13 years.

  8. A Pipeline for 3D Digital Optical Phenotyping Plant Root System Architecture

    Science.gov (United States)

    Davis, T. W.; Shaw, N. M.; Schneider, D. J.; Shaff, J. E.; Larson, B. G.; Craft, E. J.; Liu, Z.; Kochian, L. V.; Piñeros, M. A.

    2017-12-01

    This work presents a new pipeline for digital optical phenotyping the root system architecture of agricultural crops. The pipeline begins with a 3D root-system imaging apparatus for hydroponically grown crop lines of interest. The apparatus acts as a self-containing dark room, which includes an imaging tank, motorized rotating bearing and digital camera. The pipeline continues with the Plant Root Imaging and Data Acquisition (PRIDA) software, which is responsible for image capturing and storage. Once root images have been captured, image post-processing is performed using the Plant Root Imaging Analysis (PRIA) command-line tool, which extracts root pixels from color images. Following the pre-processing binarization of digital root images, 3D trait characterization is performed using the next-generation RootReader3D software. RootReader3D measures global root system architecture traits, such as total root system volume and length, total number of roots, and maximum rooting depth and width. While designed to work together, the four stages of the phenotyping pipeline are modular and stand-alone, which provides flexibility and adaptability for various research endeavors.

  9. Relationships between total length and otolith size of bluefish Pomatomus saltatrix (Linnaeus, 1766 in the Marmara Sea of Turkey

    Directory of Open Access Journals (Sweden)

    Habib Bal

    2018-01-01

    Full Text Available In the present study, bluefish, Pomatomus saltatrix, was monthly collected from commercial fishing boats operating in the Marmara Sea between January and December 2014. The relationship between total length and otolith size of 346 bluefish samples were examined. Total lengths of females, males and unidentified samples were ranged from between 13.2-37.0, 12.3-34.8 and 13.0-31.6 cm, respectively. Otolith lengths were between 3.82-12.60 mm and otolith width were between 1.59-4.34 mm for all samples. It was found that there is a strong correlations between otolith length-total length (r2 =0.88 and otolith width-total length (r2 0.81.

  10. Fine-mapping of qRL6.1, a major QTL for root length of rice seedlings grown under a wide range of NH4+ concentrations in hydroponic conditions

    Science.gov (United States)

    Tamura, Wataru; Ebitani, Takeshi; Yano, Masahiro; Sato, Tadashi; Yamaya, Tomoyuki

    2010-01-01

    Root system development is an important target for improving yield in cereal crops. Active root systems that can take up nutrients more efficiently are essential for enhancing grain yield. In this study, we attempted to identify quantitative trait loci (QTL) involved in root system development by measuring root length of rice seedlings grown in hydroponic culture. Reliable growth conditions for estimating the root length were first established to renew nutrient solutions daily and supply NH4+ as a single nitrogen source. Thirty-eight chromosome segment substitution lines derived from a cross between ‘Koshihikari’, a japonica variety, and ‘Kasalath’, an indica variety, were used to detect QTL for seminal root length of seedlings grown in 5 or 500 μM NH4+. Eight chromosomal regions were found to be involved in root elongation. Among them, the most effective QTL was detected on a ‘Kasalath’ segment of SL-218, which was localized to the long-arm of chromosome 6. The ‘Kasalath’ allele at this QTL, qRL6.1, greatly promoted root elongation under all NH4+ concentrations tested. The genetic effect of this QTL was confirmed by analysis of the near-isogenic line (NIL) qRL6.1. The seminal root length of the NIL was 13.5–21.1% longer than that of ‘Koshihikari’ under different NH4+ concentrations. Toward our goal of applying qRL6.1 in a molecular breeding program to enhance rice yield, a candidate genomic region of qRL6.1 was delimited within a 337 kb region in the ‘Nipponbare’ genome by means of progeny testing of F2 plants/F3 lines derived from a cross between SL-218 and ‘Koshihikari’. Electronic supplementary material The online version of this article (doi:10.1007/s00122-010-1328-3) contains supplementary material, which is available to authorized users. PMID:20390245

  11. Effects of rice husks and their chars from hydrothermal carbonization on the germination rate and root length of Lepidium sativum

    Science.gov (United States)

    Kern, Jürgen; Mukhina, Irina; Dicke, Christiane; Lanza, Giacomo; Kalderis, Dimitrios

    2015-04-01

    Currently, char substrates gain a lot of interest, since they are being discussed as a component in growing media, which may become one option for the replacement of peat. Among different thermal conversion processes of biomass hydrothermal carbonization (HTC) has been found to produce chars with similar acidic pH values like peat. The question however is, if these hydrochars, which may contain toxic phenolic compounds are suitable to be introduced as a new substitute for peat in horticulture. In this study rice husk were hydrothermally carbonized at 200° C for 6 hours, yielding in hydrochars containing organic contaminants such as phenols and furfurals, which may affect plants and soil organisms. We investigated potential toxic effects on the germination rate and the root length of cress salad (Lepidium sativum) in four fractions: i) soil control, ii) raw rice husk + soil, iii) unwashed rice char + soil and iv) acetone/water washed rice char + soil. It could be shown that phenols and furfurals, which were removed from the hydrochar after washing by 80 to 96% did not affect the germination rate and the root length of the cress plants. The lowest germination rate and root length were found in the soil control, the highest in the non-washed hydrochar treatment, indicating a fertilization effect and growth stimulation of cress salad by hydrochar. If this result can be confirmed for other target and non-target organisms in future studies, a new strategy for the production of growing media may be developed.

  12. Public-domain software for root image analysis

    Directory of Open Access Journals (Sweden)

    Mirian Cristina Gomes Costa

    2014-10-01

    Full Text Available In the search for high efficiency in root studies, computational systems have been developed to analyze digital images. ImageJ and Safira are public-domain systems that may be used for image analysis of washed roots. However, differences in root properties measured using ImageJ and Safira are supposed. This study compared values of root length and surface area obtained with public-domain systems with values obtained by a reference method. Root samples were collected in a banana plantation in an area of a shallower Typic Carbonatic Haplic Cambisol (CXk, and an area of a deeper Typic Haplic Ta Eutrophic Cambisol (CXve, at six depths in five replications. Root images were digitized and the systems ImageJ and Safira used to determine root length and surface area. The line-intersect method modified by Tennant was used as reference; values of root length and surface area measured with the different systems were analyzed by Pearson's correlation coefficient and compared by the confidence interval and t-test. Both systems ImageJ and Safira had positive correlation coefficients with the reference method for root length and surface area data in CXk and CXve. The correlation coefficient ranged from 0.54 to 0.80, with lowest value observed for ImageJ in the measurement of surface area of roots sampled in CXve. The IC (95 % revealed that root length measurements with Safira did not differ from that with the reference method in CXk (-77.3 to 244.0 mm. Regarding surface area measurements, Safira did not differ from the reference method for samples collected in CXk (-530.6 to 565.8 mm² as well as in CXve (-4231 to 612.1 mm². However, measurements with ImageJ were different from those obtained by the reference method, underestimating length and surface area in samples collected in CXk and CXve. Both ImageJ and Safira allow an identification of increases or decreases in root length and surface area. However, Safira results for root length and surface area are

  13. Deep rooting conferred by DEEPER ROOTING 1 enhances rice yield in paddy fields.

    Science.gov (United States)

    Arai-Sanoh, Yumiko; Takai, Toshiyuki; Yoshinaga, Satoshi; Nakano, Hiroshi; Kojima, Mikiko; Sakakibara, Hitoshi; Kondo, Motohiko; Uga, Yusaku

    2014-07-03

    To clarify the effect of deep rooting on grain yield in rice (Oryza sativa L.) in an irrigated paddy field with or without fertilizer, we used the shallow-rooting IR64 and the deep-rooting Dro1-NIL (a near-isogenic line homozygous for the Kinandang Patong allele of DEEPER ROOTING 1 (DRO1) in the IR64 genetic background). Although total root length was similar in both lines, more roots were distributed within the lower soil layer of the paddy field in Dro1-NIL than in IR64, irrespective of fertilizer treatment. At maturity, Dro1-NIL showed approximately 10% higher grain yield than IR64, irrespective of fertilizer treatment. Higher grain yield of Dro1-NIL was mainly due to the increased 1000-kernel weight and increased percentage of ripened grains, which resulted in a higher harvest index. After heading, the uptake of nitrogen from soil and leaf nitrogen concentration were higher in Dro1-NIL than in IR64. At the mid-grain-filling stage, Dro1-NIL maintained higher cytokinin fluxes from roots to shoots than IR64. These results suggest that deep rooting by DRO1 enhances nitrogen uptake and cytokinin fluxes at late stages, resulting in better grain filling in Dro1-NIL in a paddy field in this study.

  14. Barley root hair growth and morphology in soil, sand, and water solution media and relationship with nickel toxicity.

    Science.gov (United States)

    Lin, Yanqing; Allen, Herbert E; Di Toro, Dominic M

    2016-08-01

    Barley, Hordeum vulgare (Doyce), was grown in the 3 media of soil, hydroponic sand solution (sand), and hydroponic water solution (water) culture at the same environmental conditions for 4 d. Barley roots were scanned, and root morphology was analyzed. Plants grown in the 3 media had different root morphology and nickel (Ni) toxicity response. Root elongations and total root lengths followed the sequence soil > sand > water. Plants grown in water culture were more sensitive to Ni toxicity and had greater root hair length than those from soil and sand cultures, which increased root surface area. The unit root surface area as root surface area per centimeter of length of root followed the sequence water > sand > soil and was found to be related with root elongation. Including the unit root surface area, the difference in root elongation and 50% effective concentration were diminished, and percentage of root elongations can be improved with a root mean square error approximately 10% for plants grown in different media. Because the unit root surface area of plants in sand culture is closer to that in soil culture, the sand culture method, not water culture, is recommended for toxicity parameter estimation. Environ Toxicol Chem 2016;35:2125-2133. © 2016 SETAC. © 2016 SETAC.

  15. Fine Root Growth and Vertical Distribution in Response to Elevated CO2, Warming and Drought in a Mixed Heathland–Grassland

    DEFF Research Database (Denmark)

    Arndal, Marie Frost; Tolver, Anders; Larsen, Klaus Steenberg

    2018-01-01

    in single-factor experiments. In a Danish heathland ecosystem, we investigated both individual and combined effects of elevated CO2, warming and drought on fine root length, net production and standing biomass by the use of minirhizotrons, ingrowth cores and soil coring. Warming increased the net root...... production from ingrowth cores, but decreased fine root number and length in minirhizotrons, whereas there were no significant main effects of drought. Across all treatments and soil depths, CO2 stimulated both the total fine root length (+44%) and the number of roots observed (+39%), with highest relative......Belowground plant responses have received much less attention in climate change experiments than aboveground plant responses, thus hampering a holistic understanding of climate change effects on plants and ecosystems. In addition, responses of plant roots to climate change have mostly been studied...

  16. [Alveolar bone thickness and root length changes in the treatment of skeletal Class III patients facilitated by improved corticotomy: a cone-beam CT analysis].

    Science.gov (United States)

    Wu, Jiaqi; Jiang, Jiuhui; Xu, Li; Liang, Cheng; Li, Cuiying; Xu, Xiao

    2015-04-01

    To evaluate the alveolar bone thickness and root length changes of anterior teeth with cone-beam computed tomography (CBCT). CBCT scans were taken for 12 skeletal Class III patients who accepted the improved corticotomy (IC) procedures during pre-surgical orthodontics. The CBCT data in T1 (the maxillary dental arch was aligned and leveled) and T2 (extraction space closure) were superimposed and the alveolar bone thickness at root apex level and root length measurements were done. From T1 to T2, the buccal alveolar bone thickness for the upper lateral incisors increased from (1.89±0.83) to (2.47±1.02) mm (P<0.05), and for central incisors and for canines from (2.32±0.71) to (2.68±1.48) mm and from (2.28±1.08) to (2.41±1.40) mm, respectively. According to Sharpe Grading System, the root resorption grade for 69 teeth of 72 was located in Grade 1, two teeth in Grade 2, one tooth in Grade 3. The improved corticotomy had the potential to increase the buccal alveolar bone thickness and the root resorption in most teeth was in Grade 1 according to Sharpe grading system.

  17. Relationships between root respiration rate and root morphology, chemistry and anatomy in Larix gmelinii and Fraxinus mandshurica.

    Science.gov (United States)

    Jia, Shuxia; McLaughlin, Neil B; Gu, Jiacun; Li, Xingpeng; Wang, Zhengquan

    2013-06-01

    Tree roots are highly heterogeneous in form and function. Previous studies revealed that fine root respiration was related to root morphology, tissue nitrogen (N) concentration and temperature, and varied with both soil depth and season. The underlying mechanisms governing the relationship between root respiration and root morphology, chemistry and anatomy along the root branch order have not been addressed. Here, we examined these relationships of the first- to fifth-order roots for near surface roots (0-10 cm) of 22-year-old larch (Larix gmelinii L.) and ash (Fraxinus mandshurica L.) plantations. Root respiration rate at 18 °C was measured by gas phase O2 electrodes across the first five branching order roots (the distal roots numbered as first order) at three times of the year. Root parameters of root diameter, specific root length (SRL), tissue N concentration, total non-structural carbohydrates (starch and soluble sugar) concentration (TNC), cortical thickness and stele diameter were also measured concurrently. With increasing root order, root diameter, TNC and the ratio of root TNC to tissue N concentration increased, while the SRL, tissue N concentration and cortical proportion decreased. Root respiration rate also monotonically decreased with increasing root order in both species. Cortical tissue (including exodermis, cortical parenchyma and endodermis) was present in the first three order roots, and cross sections of the cortex for the first-order root accounted for 68% (larch) and 86% (ash) of the total cross section of the root. Root respiration was closely related to root traits such as diameter, SRL, tissue N concentration, root TNC : tissue N ratio and stele-to-root diameter proportion among the first five orders, which explained up to 81-94% of variation in the rate of root respiration for larch and up to 83-93% for ash. These results suggest that the systematic variations of root respiration rate within tree fine root system are possibly due to the

  18. Incidence of apical root cracks and apical dentinal detachments after canal preparation with hand and rotary files at different instrumentation lengths

    NARCIS (Netherlands)

    Liu, R.; Kaiwar, A.; Shemesh, H.; Wesselink, P.R.; Hou, B.; Wu, M.K.

    2013-01-01

    Introduction The aim of this study was to compare the incidence of apical root cracks and dentinal detachments after canal preparation with hand and rotary files at different instrumentation lengths. Methods Two hundred forty mandibular incisors were mounted in resin blocks with simulated

  19. Root length of aquatic plant, Lemna minor L., as an optimal toxicity endpoint for biomonitoring of mining effluents.

    Science.gov (United States)

    Gopalapillai, Yamini; Vigneault, Bernard; Hale, Beverley A

    2014-10-01

    Lemna minor, a free-floating macrophyte, is used for biomonitoring of mine effluent quality under the Metal Mining Effluent Regulations (MMER) of the Environmental Effects Monitoring (EEM) program in Canada and is known to be sensitive to trace metals commonly discharged in mine effluents such as Ni. Environment Canada's standard toxicity testing protocol recommends frond count (FC) and dry weight (DW) as the 2 required toxicity endpoints-this is similar to other major protocols such as those by the US Environmental Protection Agency (USEPA) and the Organisation for Economic Co-operation and Development (OECD)-that both require frond growth or biomass endpoints. However, we suggest that similar to terrestrial plants, average root length (RL) of aquatic plants will be an optimal and relevant endpoint. As expected, results demonstrate that RL is the ideal endpoint based on the 3 criteria: accuracy (i.e., toxicological sensitivity to contaminant), precision (i.e., lowest variance), and ecological relevance (metal mining effluents). Roots are known to play a major role in nutrient uptake in conditions of low nutrient conditions-thus having ecological relevance to freshwater from mining regions. Root length was the most sensitive and precise endpoint in this study where water chemistry varied greatly (pH and varying concentrations of Ca, Mg, Na, K, dissolved organic carbon, and an anthropogenic organic contaminant, sodium isopropyl xanthates) to match mining effluent ranges. Although frond count was a close second, dry weight proved to be an unreliable endpoint. We conclude that toxicity testing for the floating macrophyte should require average RL measurement as a primary endpoint. © 2014 SETAC.

  20. The interactive effect of phosphorus and nitrogen on "in vitro" spore germination of Glomus etunicatum Becker & Gerdemann, root growth and mycorrhizal colonization

    Directory of Open Access Journals (Sweden)

    Bressan Wellington

    2001-01-01

    Full Text Available The effects of P and N amendment and its interactions on spore germination, root growth and colonized root length by Glomus etunicatum Becker & Gerdemann (INVAM S329 was studied "in vitro" in RiT - DNA transformed roots of Anthylis vulneraria sub sp. Sampaiana (Kidney vetch. Three N media concentrations (5, 10 and 50 mg/l at P constant level (2 mg/l and three P media concentrations (2, 10 and 20 mg/l at N constant level (5 mg/l were utilized as a treatment. Bécard & Fortin medium was used as a basal medium for root growth and colonized root length, and water/agar (0.8% media was the control for spore germination. Spore germination of G. etunicatum at low P level was reduced by N addition in relation to the control media, and at low N level addition of P stimulated spore germination. Total root length was stimulated by N addtion at low P level, but no significant difference (p£0.05 was observed between 10 and 50 mg/l of N. P addition at low N level media also stimulated total root growth, and a significant difference (p£0.05 was observed among P concentrations. Colonized root length by G. etunicatum increased significantly (p£0.05 with P additions at low N levels. Under low P level no significant differences was found between 10 and 50 mg/l of N. These results demonstrate that the interaction between P and N affect differently spore germination, root growth and colonized root lenght.

  1. Root development during soil genesis: effects of root-root interactions, mycorrhizae, and substrate

    Science.gov (United States)

    Salinas, A.; Zaharescu, D. G.

    2015-12-01

    A major driver of soil formation is the colonization and transformation of rock by plants and associated microbiota. In turn, substrate chemical composition can also influence the capacity for plant colonization and development. In order to better define these relationships, a mesocosm study was set up to analyze the effect mycorrhizal fungi, plant density and rock have on root development, and to determine the effect of root morphology on weathering and soil formation. We hypothesized that plant-plant and plant-fungi interactions have a stronger influence on root architecture and rock weathering than the substrate composition alone. Buffalo grass (Bouteloua dactyloides) was grown in a controlled environment in columns filled with either granular granite, schist, rhyolite or basalt. Each substrate was given two different treatments, including grass-microbes and grass-microbes-mycorrhizae and incubated for 120, 240, and 480 days. Columns were then extracted and analyzed for root morphology, fine fraction, and pore water major element content. Preliminary results showed that plants produced more biomass in rhyolite, followed by schist, basalt, and granite, indicating that substrate composition is an important driver of root development. In support of our hypothesis, mycorrhizae was a strong driver of root development by stimulating length growth, biomass production, and branching. However, average root length and branching also appeared to decrease in response to high plant density, though this trend was only present among roots with mycorrhizal fungi. Interestingly, fine fraction production was negatively correlated with average root thickness and volume. There is also slight evidence indicating that fine fraction production is more related to substrate composition than root morphology, though this data needs to be further analyzed. Our hope is that the results of this study can one day be applied to agricultural research in order to promote the production of crops

  2. Root activity pattern of banana under irrigated and rain conditions

    International Nuclear Information System (INIS)

    Sobhana, A.; Aravindakshan, M.; Wahid, P.A.

    1989-01-01

    Root morphology by excavation method and root activity pattern by 32 P soil-injection technique have been studied in banana var., Nendran under rainfed/irrigated conditions. The number of roots, length and diameter of roots and dry weight of roots were found to be more for the rainfed banana crop compared to the irrigated. The results of the radiotracer studies indicated that about 60 per cent of the active roots of irrigated banana lie within 20 cm distance and about 90 per cent of the total root activity is found within 40 cm distance from the plant. In the case of rainfed crop about 85 per cent of the active roots were found within a radius of 40 cm around the plant. Active roots were found to be more concentrated at 15 to 30 cm depth under rainfed conditions while the density of active roots was more or less uniform along the profile upto a dpeth of 60 cm in irrigated banana. (author). 4 refs., 3 figs

  3. Root length densities of UK wheat and oilseed rape crops with implications for water capture and yield

    Science.gov (United States)

    White, Charlotte A.; Sylvester-Bradley, Roger; Berry, Peter M.

    2015-01-01

    Root length density (RLD) was measured to 1 m depth for 17 commercial crops of winter wheat (Triticum aestivum) and 40 crops of winter oilseed rape [Brassica napus; oilseed rape (OSR)] grown in the UK between 2004 and 2013. Taking the critical RLD (cRLD) for water capture as 1cm cm–3, RLDs appeared inadequate for full water capture on average below a depth of 0.32 m for winter wheat and below 0.45 m for OSR. These depths compare unfavourably (for wheat) with average depths of ‘full capture’ of 0.86 m and 0.48 m, respectively, determined for three wheat crops and one OSR crop studied in the 1970s and 1980s, and treated as references here. A simple model of water uptake and yield indicated that these shortfalls in wheat and OSR rooting compared with the reference data might be associated with shortfalls of up to 3.5 t ha–1 and 1.2 t ha–1, respectively, in grain yields under water-limited conditions, as increasingly occur through climate change. Coupled with decreased summer rainfall, poor rooting of modern arable crops could explain much of the yield stagnation that has been observed on UK farms since the 1990s. Methods of monitoring and improving rooting under commercial conditions are reviewed and discussed. PMID:25750427

  4. No change in total length of white matter fibers in Alzheimer's disease

    DEFF Research Database (Denmark)

    Jorgensen, A.M.; Marner, L.; Pakkenberg, B.

    2008-01-01

    White matter changes have been reported as part of Alzheimer dementia. To investigate this, the total subcortical myelinated nerve fiber length was estimated in postmortem brains from eight females (age 79-88 years) with severe Alzheimer's disease (AD) and compared with brains from 10 female...

  5. [Optimization of dissolution process for superfine grinding technology on total saponins of Panax ginseng fibrous root by response surface methodology].

    Science.gov (United States)

    Zhao, Ya; Lai, Xiao-Pin; Yao, Hai-Yan; Zhao, Ran; Wu, Yi-Na; Li, Geng

    2014-03-01

    To investigate the effects of superfine comminution extraction technology of ginseng total saponins from Panax ginseng fibrous root, and to make sure the optimal extraction condition. Optimal condition of ginseng total saponins from Panax ginseng fibrous root was based on single factor experiment to study the effects of crushing degree, extraction time, alcohol concentration and extraction temperature on extraction rate. Response surface method was used to investigate three main factors such as superfine comminution time, extraction time and alcohol concentration. The relationship between content of ginseng total saponins in Panax ginseng fibrous root and three factors fitted second degree polynomial models. The optimal extraction condition was 9 min of superfine comminution time, 70% of alcohol, 50 degrees C of extraction temperature and 70 min of extraction time. Under the optimal condition, ginseng total saponins from Panax ginseng fibrous root was average 94. 81%, which was consistent with the predicted value. The optimization of technology is rapid, efficient, simple and stable.

  6. Uncovering genes and ploidy involved in the high diversity in root hair density, length and response to local scarce phosphate in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Markus G Stetter

    Full Text Available Plant root hairs increase the root surface to enhance the uptake of sparingly soluble and immobile nutrients, such as the essential nutrient phosphorus, from the soil. Here, root hair traits and the response to scarce local phosphorus concentration were studied in 166 accessions of Arabidopsis thaliana using split plates. Root hair density and length were correlated, but highly variable among accessions. Surprisingly, the well-known increase in root hair density under low phosphorus was mostly restricted to genotypes that had less and shorter root hairs under P sufficient conditions. By contrast, several accessions with dense and long root hairs even had lower hair density or shorter hairs in local scarce phosphorus. Furthermore, accessions with whole-genome duplications developed more dense but phosphorus-insensitive root hairs. The impact of genome duplication on root hair density was confirmed by comparing tetraploid accessions with their diploid ancestors. Genome-wide association mapping identified candidate genes potentially involved in root hair responses tp scarce local phosphate. Knock-out mutants in identified candidate genes (CYR1, At1g32360 and RLP48 were isolated and differences in root hair traits in the mutants were confirmed. The large diversity in root hair traits among accessions and the diverse response when local phosphorus is scarce is a rich resource for further functional analyses.

  7. Adaptation of fine roots to annual fertilization and irrigation in a 13-year-old Pinus pinaster stand.

    Science.gov (United States)

    Bakker, M R; Jolicoeur, E; Trichet, P; Augusto, L; Plassard, C; Guinberteau, J; Loustau, D

    2009-02-01

    Effects of fertilization and irrigation on fine roots and fungal hyphae were studied in 13-year-old maritime pine (Pinus pinaster Aït. in Soland), 7 years after the initiation of the treatments. The fertilization trials consisted of a phosphorus treatment, a complete fertilizer treatment (N, P, K, Ca and Mg), and an unfertilized treatment (control). Fertilizers were applied annually and were adjusted according to foliar target values. Two irrigation regimes (no irrigation and irrigation of a set amount each day) were applied from May to October. Root samples to depths of 120 cm were collected in summer of 2005, and the biomass of small roots (diameter 2-20 mm) and fine roots (diameter root morphology were assessed. Biomass and length of hyphae were studied by a mesh ingrowth bag technique. Total fine root biomass in the litter and in the 0-120 cm soil profile ranged between 111 and 296 g m(-2). Results derived from the measurements of biomass and root length, or root area, showed that both fertilizer treatments reduced the size of the fine root system, especially in the top soil layers, but did not affect small roots. Compared with control treatments, fine root morphology was affected by both fertilizer treatments with the fine roots having increased specific root length/area, and irrigation tended to reinforce this finer morphology. The amount of hyphae in the mesh ingrowth bags was higher in the fertilization and irrigation treatments than in the controls, suggesting further extension of the root system (ectomycorrhizal infection) and thus of the uptake system. Irrigation had no significant effect on the size of the fine root system, but resulted in a shallower rooting system. Total root to shoot ratios were unaffected by the treatments, but fine root mass:needle mass and fine root area index:leaf area index ratios decreased with increasing nutrient supply. Overall, compared with the control fine roots, increased nutrient supply resulted in a

  8. Evaluation of allelopathic impact of aqueous extract of root and aerial root of Tinospora cordifolia (Willd. miers on some weed plants

    Directory of Open Access Journals (Sweden)

    K. M. Abdul RAOOF

    2012-05-01

    Full Text Available The present laboratory experimental study was conducted to evaluate the allelopathic potential of Tinospora cordifolia (Willd. Miers on seed germination and seedling growth of weed plants (Chenopodium album L. Chenopodium murale L., Cassia tora L. and Cassia sophera L.. Root and aerial root aqueous extracts of Tinospora at 0.5, 1.0, 2.0 and 4.0% concentrations were applied to determine their effect on seed germination and seedling growth of test plants under laboratory conditions. Germination was observed for 15 days after that the root length and shoot length was measured. Dry weight was measured after oven drying the seedlings. The aqueous extracts from root and aerial root had inhibitory effect on seed germination of test plants. Aqueous extracts from root and aerial root significantly inhibited not only germination and seedling growth but also reduced dry weight of the seedlings. Root length, shoot length of weed species decreased progressively when plants were exposed to increasing concentration (0.5, 1, 2 and 4%. Aqueous extract of aerial root shows the least inhibition. The pH of aqueous extracts of different parts of T. cordifolia does not show any major change when the concentration increases.

  9. Root systems and soil microbial biomass under no-tillage system

    Directory of Open Access Journals (Sweden)

    Venzke Filho Solismar de Paiva

    2004-01-01

    Full Text Available Some root parameters such as distribution, length, diameter and dry matter are inherent to plant species. Roots can influence microbial population during vegetative cycle through the rhizodeposits and, after senescence, integrating the soil organic matter pool. Since they represent labile substrates, especially regarding nitrogen, they can determine the rate of nutrient availability to the next crop cultivated under no-tillage (NT. The root systems of two crop species: maize (Zea mays L. cultivar Cargill 909 and soybean [Glycine max (L. Merr.] cultivar Embrapa 59, were compared in the field, and their influence on spatial distribution of the microbial C and N in a clayey-textured Typic Hapludox cultivated for 22 years under NT, at Tibagi, State of Paraná (PR, Brazil, was determined. Digital image processing and nail-plate techniques were used to evaluate 40 plots of a 80 ´ 50 ´ 3 cm soil profile. It was observed that 36% and 30% of the maize and soybeans roots, respectively, are concentrated in the 0 to 10 cm soil layer. The percent distribution of root dry matter was similar for both crops. The maize roots presented a total of 1,324 kg C ha-1 and 58 kg N ha-1, with higher root dry matter density and more roots in decomposition in the upper soil layer, decreasing with depth. The soybean roots (392 kg C ha-1 and 21 kg N ha-1 showed higher number of thinner roots and higher density per length unity compared to the maize. The maize roots enhanced microbial-C down to deeper soil layers than did the soybean roots. The microbial N presented a better correlation with the concentration of thin active roots and with roots in decomposition or in indefinite shape, possibly because of higher concentration of C and N easily assimilated by soil microorganisms.

  10. A micro-computed tomographic evaluation of dentinal microcrack alterations during root canal preparation using single-file Ni-Ti systems.

    Science.gov (United States)

    Li, Mei-Lin; Liao, Wei-Li; Cai, Hua-Xiong

    2018-01-01

    The aim of the present study was to evaluate the length of dentinal microcracks observed prior to and following root canal preparation with different single-file nickel-titanium (Ni-Ti) systems using micro-computed tomography (micro-CT) analysis. A total of 80 mesial roots of mandibular first molars presenting with type II Vertucci canal configurations were scanned at an isotropic resolution of 7.4 µm. The samples were randomly assigned into four groups (n=20 per group) according to the system used for root canal preparation, including the WaveOne (WO), OneShape (OS), Reciproc (RE) and control groups. A second micro-CT scan was conducted after the root canals were prepared with size 25 instruments. Pre- and postoperative cross-section images of the roots (n=237,760) were then screened to identify the lengths of the microcracks. The results indicated that the microcrack lengths were notably increased following root canal preparation (Pfiles. Among the single-file Ni-Ti systems, WO and RE were not observed to cause notable microcracks, while the OS system resulted in evident microcracks.

  11. [Effects of tree species diversity on fine-root biomass and morphological characteristics in subtropical Castanopsis carlesii forests].

    Science.gov (United States)

    Wang, Wei-Wei; Huang, Jin-Xue; Chen, Feng; Xiong, De-Cheng; Lu, Zheng-Li; Huang, Chao-Chao; Yang, Zhi-Jie; Chen, Guang-Shui

    2014-02-01

    Fine roots in the Castanopsis carlesii plantation forest (MZ), the secondary forest of C. carlesii through natural regeneration with anthropogenic promotion (AR), and the secondary forest of C. carlesii through natural regeneration (NR) in Sanming City, Fujian Province, were estimated by soil core method to determine the influence of tree species diversity on biomass, vertical distribution and morphological characteristics of fine roots. The results showed that fine root biomass for the 0-80 cm soil layer in the MZ, AR and NR were (182.46 +/- 10.81), (242.73 +/- 17.85) and (353.11 +/- 16.46) g x m(-2), respectively, showing an increased tendency with increasing tree species diversity. In the three forests, fine root biomass was significantly influenced by soil depth, and fine roots at the 0-10 cm soil layer accounted for more than 35% of the total fine root biomass. However, the interaction of stand type and soil depth on fine-root distribution was not significant, indicating no influence of tree species diversity on spatial niche segregation in fine roots. Root surface area density and root length density were the highest in NR and lowest in the MZ. Specific root length was in the order of AR > MZ > NR, while specific root surface area was in the order of NR > MZ > AR. There was no significant interaction of stand type and soil depth on specific root length and specific root surface area. Fine root morphological plasticity at the stand level had no significant response to tree species diversity.

  12. Physical properties of root cementum: Part 26. Effects of micro-osteoperforations on orthodontic root resorption: A microcomputed tomography study.

    Science.gov (United States)

    Chan, Emmanuel; Dalci, Oyku; Petocz, Peter; Papadopoulou, Alexandra K; Darendeliler, M Ali

    2018-02-01

    Studies have demonstrated the potential efficacy of micro-osteoperforations in accelerating tooth movement by amplifying the expression of inflammatory markers. The aim of this investigation was to examine the effects of micro-osteoperforations on orthodontic root resorption with microcomputed tomography. This prospective controlled clinical trial involved 20 subjects requiring extraction of the maxillary first premolars as part of their orthodontic treatment. A buccal tipping force of 150 g was applied to both premolars. Using the Propel appliance (Propel Orthodontics, San Jose, Calif), micro-osteoperforations were applied at a depth of 5 mm on the mesial and distal aspects in the midroot region of the experimental side of the first premolar root; the contralateral side served as the control. After 28 days, both premolars were extracted. The teeth were scanned under microcomputed tomography, and the volumes of root resorption craters were calculated and compared. Premolars treated with micro-osteoperforation exhibited significantly greater average total amounts of root resorption than did the control teeth (0.576 vs 0.406 mm 3 ). The total average volumetric root loss of premolars treated with micro-osteoperforation was 42% greater than that of the control teeth. This 28-day trial showed that micro-osteoperforations resulted in greater orthodontic root resorption. However, these results should be verified in patients who are undergoing full-length orthodontic treatment. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  13. Comparison of digital radiography and apex locator with the conventional method in root length determination of primary teeth

    Directory of Open Access Journals (Sweden)

    I E Neena

    2011-01-01

    Full Text Available Aim: The purpose of this study was to compare the Working length in primary teeth endodontics using intra oral digital radiovisiography and apex locator with conventional method for accuracy. Materials and Methods: This in vivo study was conducted on 30 primary teeth which were indicated for pulpectomy in the patients of the age group of 5-11 years All experimental teeth had adequate remaining tooth structure for rubber dam isolation and radiographicaly visible canals. Endodontic treatment was required due to irreversible pulpitis or pulp necrosis. A standardized intraoral periapical radiograph of the tooth was taken using conventional method by paralleling technique. The distance between the source and the tooth, tooth and the films were standardized using X-ray positioning device. During the pulpectomy procedure, the working length was determined by digital radiograph and apex locator. The measurements were then compared with the conventional method of root canal measurement technique for accuracy Result: From the results obtained we can conclude that Working length determined in primary molars using digital radiography and Apex locator did not show any significant difference in the mean working length measurements when compared with the conventional radiographic method. Conclusions: Apex locator is comparable to conventional radiograph in determining the working length without radiation in the primary teeth. Intraoral digital radiography is the safest method in determining the working length with significant reduction in radiation exposure.Hence, both the techniques can be safely used as alternatives to conventional radiographic methods in determining working length in primary teeth.

  14. Root Morphology Was Improved in a Late-Stage Vigor Super Rice Cultivar.

    Directory of Open Access Journals (Sweden)

    Min Huang

    Full Text Available This study aimed to test the hypothesis that root morphology might be improved and consequently contributing to superior post-heading shoot growth and grain yield in late-stage vigor super rice. A pot experiment was carried out to compare yield attributes, shoot growth and physiological properties and root morphological traits between a late-stage vigor super rice cultivar (Y-liangyou 087 and an elite rice cultivar (Teyou 838. Grain yield and total shoot biomass were 7-9% higher in Y-liangyou 087 than in Teyou 838. Y-liangyou 087 had 60-64% higher post-heading shoot growth rate and biomass production than Teyou 838. Average relative chlorophyll concentration and net photosynthetic rate in flag leaves were 7-11% higher in Y-liangyou 087 than in Teyou 838 during heading to 25 days after heading. Y-liangyou 087 had 41% higher post-heading shoot N uptake but 17-25% lower root biomass and root-shoot ratio at heading and maturity than Teyou 838. Specific root length and length and surface area of fine roots were higher in Y-liangyou 087 than in Teyou 838 at heading and maturity by more than 15%. These results indicated that root-shoot relationships were well balanced during post-heading phase in the late-stage vigor super rice cultivar Y-liangyou 087 by improving root morphology including avoiding a too great root biomass and developing a large fine root system.

  15. Root Morphology Was Improved in a Late-Stage Vigor Super Rice Cultivar.

    Science.gov (United States)

    Huang, Min; Chen, Jiana; Cao, Fangbo; Jiang, Ligeng; Zou, Yingbin

    2015-01-01

    This study aimed to test the hypothesis that root morphology might be improved and consequently contributing to superior post-heading shoot growth and grain yield in late-stage vigor super rice. A pot experiment was carried out to compare yield attributes, shoot growth and physiological properties and root morphological traits between a late-stage vigor super rice cultivar (Y-liangyou 087) and an elite rice cultivar (Teyou 838). Grain yield and total shoot biomass were 7-9% higher in Y-liangyou 087 than in Teyou 838. Y-liangyou 087 had 60-64% higher post-heading shoot growth rate and biomass production than Teyou 838. Average relative chlorophyll concentration and net photosynthetic rate in flag leaves were 7-11% higher in Y-liangyou 087 than in Teyou 838 during heading to 25 days after heading. Y-liangyou 087 had 41% higher post-heading shoot N uptake but 17-25% lower root biomass and root-shoot ratio at heading and maturity than Teyou 838. Specific root length and length and surface area of fine roots were higher in Y-liangyou 087 than in Teyou 838 at heading and maturity by more than 15%. These results indicated that root-shoot relationships were well balanced during post-heading phase in the late-stage vigor super rice cultivar Y-liangyou 087 by improving root morphology including avoiding a too great root biomass and developing a large fine root system.

  16. Study of root para-nodules formation in wheat (Triticum durum ...

    African Journals Online (AJOL)

    djemel

    2013-08-28

    Aug 28, 2013 ... African Journal of Biotechnology. Full Length Research ... formed when wheat roots were inoculated with Frankia and the root length was enhanced. When the .... are modified lateral roots with structure enhanced by rhizobial.

  17. Do climate variables and human density affect Achatina fulica (Bowditch) (Gastropoda: Pulmonata) shell length, total weight and condition factor?

    Science.gov (United States)

    Albuquerque, F S; Peso-Aguiar, M C; Assunção-Albuquerque, M J T; Gálvez, L

    2009-08-01

    The length-weight relationship and condition factor have been broadly investigated in snails to obtain the index of physical condition of populations and evaluate habitat quality. Herein, our goal was to describe the best predictors that explain Achatina fulica biometrical parameters and well being in a recently introduced population. From November 2001 to November 2002, monthly snail samples were collected in Lauro de Freitas City, Bahia, Brazil. Shell length and total weight were measured in the laboratory and the potential curve and condition factor were calculated. Five environmental variables were considered: temperature range, mean temperature, humidity, precipitation and human density. Multiple regressions were used to generate models including multiple predictors, via model selection approach, and then ranked with AIC criteria. Partial regressions were used to obtain the separated coefficients of determination of climate and human density models. A total of 1.460 individuals were collected, presenting a shell length range between 4.8 to 102.5 mm (mean: 42.18 mm). The relationship between total length and total weight revealed that Achatina fulica presented a negative allometric growth. Simple regression indicated that humidity has a significant influence on A. fulica total length and weight. Temperature range was the main variable that influenced the condition factor. Multiple regressions showed that climatic and human variables explain a small proportion of the variance in shell length and total weight, but may explain up to 55.7% of the condition factor variance. Consequently, we believe that the well being and biometric parameters of A. fulica can be influenced by climatic and human density factors.

  18. Do climate variables and human density affect Achatina fulica (Bowditch (Gastropoda: Pulmonata shell length, total weight and condition factor?

    Directory of Open Access Journals (Sweden)

    FS. Albuquerque

    Full Text Available The length-weight relationship and condition factor have been broadly investigated in snails to obtain the index of physical condition of populations and evaluate habitat quality. Herein, our goal was to describe the best predictors that explain Achatina fulica biometrical parameters and well being in a recently introduced population. From November 2001 to November 2002, monthly snail samples were collected in Lauro de Freitas City, Bahia, Brazil. Shell length and total weight were measured in the laboratory and the potential curve and condition factor were calculated. Five environmental variables were considered: temperature range, mean temperature, humidity, precipitation and human density. Multiple regressions were used to generate models including multiple predictors, via model selection approach, and then ranked with AIC criteria. Partial regressions were used to obtain the separated coefficients of determination of climate and human density models. A total of 1.460 individuals were collected, presenting a shell length range between 4.8 to 102.5 mm (mean: 42.18 mm. The relationship between total length and total weight revealed that Achatina fulica presented a negative allometric growth. Simple regression indicated that humidity has a significant influence on A. fulica total length and weight. Temperature range was the main variable that influenced the condition factor. Multiple regressions showed that climatic and human variables explain a small proportion of the variance in shell length and total weight, but may explain up to 55.7% of the condition factor variance. Consequently, we believe that the well being and biometric parameters of A. fulica can be influenced by climatic and human density factors.

  19. Nodal distances for rooted phylogenetic trees.

    Science.gov (United States)

    Cardona, Gabriel; Llabrés, Mercè; Rosselló, Francesc; Valiente, Gabriel

    2010-08-01

    Dissimilarity measures for (possibly weighted) phylogenetic trees based on the comparison of their vectors of path lengths between pairs of taxa, have been present in the systematics literature since the early seventies. For rooted phylogenetic trees, however, these vectors can only separate non-weighted binary trees, and therefore these dissimilarity measures are metrics only on this class of rooted phylogenetic trees. In this paper we overcome this problem, by splitting in a suitable way each path length between two taxa into two lengths. We prove that the resulting splitted path lengths matrices single out arbitrary rooted phylogenetic trees with nested taxa and arcs weighted in the set of positive real numbers. This allows the definition of metrics on this general class of rooted phylogenetic trees by comparing these matrices through metrics in spaces M(n)(R) of real-valued n x n matrices. We conclude this paper by establishing some basic facts about the metrics for non-weighted phylogenetic trees defined in this way using L(p) metrics on M(n)(R), with p [epsilon] R(>0).

  20. Effect of customization of master gutta-percha cone on apical control of root filling using different techniques: an ex vivo study.

    Science.gov (United States)

    van Zyl, S P; Gulabivala, K; Ng, Y-L

    2005-09-01

    (i) To compare the prevalence of extrusion of root filling material when placed using different root filling techniques, with or without customization of the master gutta-percha (GP) cone; and (ii) to investigate the effects of some factors influencing root filling extrusion and presence of voids. A total of 180 roots were selected, prepared and randomly allocated to three groups. Five general dental practitioners performed the root fillings; each filled one group of roots (n = 60) using each of three techniques; 'cold lateral compaction' (n = 20), 'warm vertical compaction' (n = 20) and 'continuous-wave' (n = 20) techniques. For each obturation technique, the master GP cone was customized using chloroform in 10 samples. Two groups of the roots were recycled to allow all five operators to fulfill their remit. Two observers, blind to operator and obturation technique, examined the radiographs (master apical file, post-obturation) to determine the presence of root filling extrusion and voids within the apical 5 mm, independently. Root filling extrusion was also confirmed by direct inspection of the root apex after obturation. The data were analysed using logistic regression models. A total of 300 root fillings were performed; nine were excluded from the analysis. Most of the root fillings (80%, n = 233) were placed within 0.5 mm of the working length; only 20% (n = 58) were placed >0.5 mm beyond the working length. The odds of prevalence of extrusion (>0.5 mm) were significantly reduced by about 50% when cold lateral compaction or customization of GP were used. One operator produced 2.5 times more extruded root fillings than others. Curvature & length of root canal, apical size of prepared canal, as well as operator's preferred obturation technique had no significant influence on the prevalence of extrusion. Customization of GP was the sole factor to significantly reduce the prevalence of voids within the apical 5 mm of working length. Root filling extrusion was

  1. Root growth during molar eruption in extant great apes.

    Science.gov (United States)

    Kelley, Jay; Dean, Christopher; Ross, Sasha

    2009-01-01

    While there is gradually accumulating knowledge about molar crown formation and the timing of molar eruption in extant great apes, very little is known about root formation during the eruption process. We measured mandibular first and second molar root lengths in extant great ape osteological specimens that died while either the first or second molars were in the process of erupting. For most specimens, teeth were removed so that root lengths could be measured directly. When this was not possible, roots were measured radiographically. We were particularly interested in the variation in the lengths of first molar roots near the point of gingival emergence, so specimens were divided into early, middle and late phases of eruption based on the number of cusps that showed protein staining, with one or two cusps stained equated with immediate post-gingival emergence. For first molars at this stage, Gorilla has the longest roots, followed by Pongo and Pan. Variation in first molar mesial root lengths at this stage in Gorilla and Pan, which comprise the largest samples, is relatively low and represents no more than a few months of growth in both taxa. Knowledge of root length at first molar emergence permits an assessment of the contribution of root growth toward differences between great apes and humans in the age at first molar emergence. Root growth makes up a greater percentage of the time between birth and first molar emergence in humans than it does in any of the great apes. Copyright (c) 2009 S. Karger AG, Basel.

  2. Initial root length in wheat is highly correlated with acid soil tolerance in the field

    Directory of Open Access Journals (Sweden)

    Jorge Fernando Pereira

    Full Text Available ABSTRACT: In acid soils, toxic aluminum ions inhibit plant root growth. In order to discriminate aluminum (Al tolerance, trustful screening techniques are required. In this study, 20 wheat cultivars, showing different levels of Al tolerance, were evaluated in a short-term soil experiment to access their relative root length (RRL. Moreover, the alleles of two important genes (TaALMT1 and TaMATE1B for Al tolerance in wheat were discriminated. Both of these genes encode membrane transporters responsible for the efflux of organic acids by the root apices that are thought to confer tolerance by chelating Al. Genotypes showing TaALMT1 alleles V and VI and an insertion at the TaMATE1B promoter were among the ones showing greater RRL. Mechanisms of Al tolerance, which are not associated with organic acid efflux, can be potentially present in two cultivars showing greater RRL among the ones carrying inferior TaALMT1 and TaMATE1B alleles. The RRL data were highly correlated with wheat performance in acid soil at three developmental stages, tillering (r = −0.93, p < 0.001, silking (r = −0.91, p < 0.001 and maturation (r = −0.90, p < 0.001, as well as with the classification index of aluminum toxicity in the field (r = −0.92, p < 0.001. Since the RRL was obtained after only six days of growth and it is highly correlated with plant performance in acid soil under field conditions, the short-term experiment detailed here is an efficient and rapid method for reliable screening of wheat Al tolerance.

  3. Adult root structure of Mediterranean shrubs: relationship with post-fire regenerative syndrome.

    Science.gov (United States)

    Saura-Mas, S; Lloret, F

    2014-01-01

    Life-history attributes can impose differences on root system structures and properties related to nutrient and water uptake. Here, we assess whether plants with different post-fire regenerative strategies (resprouters, seeders and seeder-resprouters) differ in the topological and morphological properties of their root systems (external path, altitude, magnitude, topological index, specific root length, root length, root-to-shoot biomass ratio, length of the main axis of the root system and link length). To achieve these objectives, we sampled individuals from eight woody species in a shrubland located in the western Mediterranean Basin. We sampled the adult root systems using manual field excavation with the aid of an air compressor. The results indicate that resprouters have a higher root-to-shoot ratio, confirming their higher ability to store water, starch and nutrients and to invest in the belowground biomass. Moreover, this pattern would allow them to explore deeper parts of the soil layers. Seeder species would benefit from a higher specific root length, pointing to increased relative root growth and water uptake rates. This study confirms that seeders and resprouters may differ in nutrient and water uptake ability according to the characteristics of their root system. Species that can both resprout and establish seedlings after fire had different patterns of root system structure; in particular, root:shoot ratio was more similar to resprouters and specific root length was closer to seeders, supporting the distinct functional performance of this type of species. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

  4. Tuberous root characteristics of sweet potato clones using multivariate techniques for selection of superior genotypes

    Directory of Open Access Journals (Sweden)

    Jackson da Silva

    2018-01-01

    Full Text Available The objective of this study was to evaluate the tuberous root characteristics of sweet potato clones using multivariate techniques for selection of superior genotypes, the present research was carried out in the Experimental area of the Plant Genetic Breeding Sector of the Agrarian Sciences Center of the Federal University of Alagoas (SMGP/CECA/UFAL. Were evaluated 44 new clones originated from progenies of half-siblings and germanic siblings, in addition to the cultivar Sergipana Vermelha, in lines of 5 m in length, spacing 1.0 mx 0.5 m, totaling a total area of 5 m²/clone. The harvest was done at 120 days after planting the branches, in which the production of non-commercial tuberous roots (PRTNC was evaluated, production of commercial tuberous roots (PRTC, production of tuberous roots (PTRT, total number of tuberous roots (NTRT, average weight of commercial tuberous roots (PMRTC, predominant color of tuberous root skin (CPPERT and predominant color of the tuberosal root pulp (CPPORT. Descriptive statistics, correlation technique and principal component analysis were used. It was observed that clones 23, 36, 17 and 37 presented interesting agronomic characteristics, being recommended for the cultivation and in the analysis of main components, the variables PTRT and PRTC presented greater importance, reflecting that they discriminate the clones satisfactorily.

  5. Root morphological responses of three hot pepper cultivars to Cd exposure and their correlations with Cd accumulation.

    Science.gov (United States)

    Huang, Baifei; Xin, Junliang; Dai, Hongwen; Liu, Aiqun; Zhou, Wenjing; Yi, Yumei; Liao, Kebing

    2015-01-01

    Cultivars of hot pepper (Capsicum annuum L.) differ widely in their fruit cadmium (Cd) concentrations. Previously, we suggested that low-Cd cultivars are better able to prevent the translocation of Cd from roots to aboveground parts, but the corresponding mechanisms are still unknown. In this study, we aimed to improve understanding of the root morphological characteristics of the mechanisms involved in two low-Cd and a high-Cd cultivar. Seedlings were grown in nutrient solutions containing 0 (control), 2, and 10 μM Cd for 20 days, and Cd contents for the three cultivars were compared with changes in root morphology. The total root length (RL), root surface area (SA), number of root tips (RT), and specific root length (SRL) of all cultivars were decreased significantly by the 10 μM Cd treatment with the exception of the SA in JFZ, which showed no obvious change. For each cultivar, the 10 μM Cd treatment decreased significantly RL and SA specifically in roots with diameters (RD) of RD ≤ 0.2 mm or 0.2 mm roots with diameters of 0.6 mm root morphology. In the 10 μM Cd treatment, root volume (RV), SA, and RT of all cultivars were negatively correlated with Cd concentration and amount in roots. However, RL, SA, RV, and RT of all cultivars were positively correlated with Cd concentration and amount in shoots, and translocation rate of Cd. The two low-Cd cultivars of hot pepper had less root tips, shorter root length, and smaller root surface area than the high-Cd cultivar in 10 μM Cd treatment, which may play a vital role in reducing root-to-shoot Cd translocation.

  6. Diversity effects on root length production and loss in an experimental grassland community

    NARCIS (Netherlands)

    Mommer, L.; Padilla, F.M.; Ruijven, van J.; Caluwe, de H.; Smit-Tiekstra, A.E.; Berendse, F.; Kroon, de H.

    2015-01-01

    Advances in root ecology have revealed that root standing biomass is higher in species-rich plant communities than in species-poor communities. Currently, we do not know whether this below-ground diversity effect is the result of enhanced root production or reduced root mortality or both, which is

  7. Variation of root system characters in collection of semi-dwarf spring barley mutants

    International Nuclear Information System (INIS)

    Nawrot, M.; Zbieszczyk, J.; Maluszynski, M.

    2000-01-01

    The collection of 371 semi-dwarf mutants, derived from 12 spring barley varieties has been used as material for analysis of root system. The mutants have been obtained after mutagenic treatment with N-methyl-N-nitroso urea (MNH), sodium azide (NaN3), gamma-rays and fast neutrons. The following analysis of root system were performed: seminal root growth of 8-day old seedlings, seminal and adventitious root growth of 6-week old plants and dynamics of root growth during first 6 weeks of plant growth. Seminal root length, root number and the length of the first leaf in barley mutants were investigated with the use of paper rollers. Root system analysis of 6-week old plants was performed on genotypes grown in PVC tubes filled with sand, supplemented with 1 mineral salts of MS medium. The following measurements were made: the length of the longest seminal root and the longest adventitious root, the number of adventitious roots and the number of tillers. Analysis of dynamics of root growth during the first six weeks of vegetation was performed at the end of each 7-day growth period in the PVC tubes filled with sand. Great variability in the seminal root length was found in analysed 8-day old seedling population. Almost half of the analysed mutants showed significant root length reduction, but about ten percent of semi-dwarf mutants developed roots with an increased length in comparison to parents. No significant differences were found between analysed mutants and corresponding parent varieties regarding the number of seminal roots. After six weeks of growth, the selected mutants showed differences in the reduction of root length in comparison to the 8-day old seedlings. The results of root growth dynamics indicated that analysed mutants had different patterns in comparison to the parent variety. Differences in the growth dynamics were also observed among the parent varieties. The observed differences in pattern of root growth between mutants and corresponding parents

  8. Effect of different irrigation systems on root growth of maize and cowpea plants in sandy soil

    Directory of Open Access Journals (Sweden)

    Noha A. Mahgoub

    2017-10-01

    Full Text Available A field experiment was conducted at the Experimental Farm, Faculty of Agriculture, Suez Canal University to study the influence of different irrigation systems on root length density and specific root length of maize and cowpea plants cultivated in sandy soil. Three irrigation systems (Surface, drip and sprinkler irrigation were used in this study. The NPK fertilizers were applied as recommended doses for maize and cowpea. Root samples were collected from the soil profile below one plant (maize and cowpea which was irrigated by the three irrigation systems by using an iron box (30 cm× 20 cm which is divided into 24 small boxes each box is (5× 5 × 5 cm. At surface irrigation, root length density of cowpea reached to soil depth 30-40cm with lateral distances 5-10 cm and 15-20 cm. Vertical distribution of root length density of maize was increased with soil depth till 20-25 cm, and then it decreased till soil depth 35-40cm. Under drip irrigation, root length density of cowpea increased horizontally from 0-5cm to 10-15cm then it decreased till soil depth 25-30 cm and below this depth root length density disappeared. For the root length density and specific root length of maize under drip irrigation, the data showed that root length density and specific root length decreased with increasing in soil depth. The root length density of cowpea under sprinkler irrigation at 0-5cm disappeared from horizontal distance at 25-30 cm. The data showed that root length density of maize under sprinkler irrigation was higher at the soil top layers 0-5 cm and 5-10 cm than other layers from 10-40 cm.

  9. Roentgenologic investigations for the anterior tooth length

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Won Pyo; Ahn, Hyung Kyu [College of Dentistry, Seoul National University , Seoul (Korea, Republic of)

    1972-11-15

    The author measured the length of crown, root and tooth on the films which was taken by intraoral bisecting technic with mesh plate on the films. The films were taken from the dry skulls, dentiform, same patients who had to be removed their upper incisors, and the other patients who admitted for dental care. From this serial experiment the results were made as follows: 1. By using the film and mesh plate in the oral cavity, the real tooth length can be measured easily on the film surfaces. 2. The film distortion in the oral cavity can be avoided when taking the film using the mesh plate and film together. 3. When measuring the film, length of crown was elongated and length of root was shortened. 4. When using the well-trained bisecting technic, the real tooth length can be measured directly on the intraoral film.

  10. QTL-By-Environment Interaction in the Response of Maize Root and Shoot Traits to Different Water Regimes

    Directory of Open Access Journals (Sweden)

    Pengcheng Li

    2018-02-01

    Full Text Available Drought is a major abiotic stress factor limiting maize production, and elucidating the genetic control of root system architecture and plasticity to water-deficit stress is a crucial problem to improve drought adaptability. In this study, 13 root and shoot traits and genetic plasticity were evaluated in a recombinant inbred line (RIL population under well-watered (WW and water stress (WS conditions. Significant phenotypic variation was observed for all observed traits both under WW and WS conditions. Most of the measured traits showed significant genotype–environment interaction (GEI in both environments. Strong correlations were observed among traits in the same class. Multi-environment (ME and multi-trait (MT QTL analyses were conducted for all observed traits. A total of 48 QTLs were identified by ME, including 15 QTLs associated with 9 traits showing significant QTL-by-Environment interactions (QEI. QTLs associated with crown root angle (CRA2 and crown root length (CRL1 were identified as having antagonistic pleiotropic effects, while 13 other QTLs showed signs of conditional neutrality (CN, including 9 and 4 QTLs detected under WW and WS conditions, respectively. MT analysis identified 14 pleiotropic QTLs for 13 traits, SNP20 (1@79.2 cM was associated with the length of crown root (CR, primary root (PR, and seminal root (SR and might contribute to increases in root length under WS condition. Taken together, these findings contribute to our understanding of the phenotypic and genotypic patterns of root plasticity in response to water deficiency, which will be useful to improve drought tolerance in maize.

  11. Root hair defective4 encodes a phosphatidylinositol-4-phosphate phosphatase required for proper root hair development in Arabidopsis thaliana

    NARCIS (Netherlands)

    Thole, J.M.; Vermeer, J.E.M.; Zhang, Y.; Gadella, Th.W.J.; Nielsen, E.

    2008-01-01

    Polarized expansion of root hair cells in Arabidopsis thaliana is improperly controlled in root hair-defective rhd4-1 mutant plants, resulting in root hairs that are shorter and randomly form bulges along their length. Using time-lapse fluorescence microscopy in rhd4-1 root hairs, we analyzed

  12. Root resorption following periodontally accelerated osteogenic orthodontics

    Directory of Open Access Journals (Sweden)

    Donald J Ferguson

    2016-01-01

    Full Text Available Background: Literature evidence suggests that root resorption, an adverse side effect of orthodontic therapy, may be decreased under conditions of alveolar osteopenia, a condition characterized by diminished bone density and created secondary to alveolar corticotomy (Cort surgery. Purpose: To compare root resorption of the maxillary central incisors following nonextraction orthodontic therapy with and without Cort surgery. Materials and Methods: The sample comprised two groups, with and without Cort and was matched by age and gender: Cort-facilitated nonextraction orthodontics with 27 subjects, 53 central incisors of mean age 24.8 ± 10.2 years, and conventional (Conv nonextraction orthodontics with 27 subjects, 54 incisors with mean age of 19.6 ± 8.8 years. All periapical radiographs were taken with the paralleling technique; total tooth lengths of the right and left central incisors were measured by projecting and enlarging the periapical radiographs exactly 8 times. Results: t-tests revealed a significant decrease in treatment time in the Cort group (6.3 ± 8.0 vs. 17.4 ± 20.2 months, P = 0.000. Pretreatment root lengths were not significantly different (P = 0.11, but Conv had significantly shorter roots at posttreatment when compared with Cort (P = 0.03. Significant root resorption (P < 0.01 occurred in both Cort (0.3 mm and Conv (0.7 mm, but the increment of change was significantly greater in Conv (P < 0.03. The variable SNA increased significantly in the Cort (P = 0.001 group and decreased significantly in the Conv group (P < 0.001. Conclusions: Based on the conditions of this study, it may be concluded that Cort-facilitated nonextraction orthodontic therapy results in less root resorption and enhanced alveolar support within a significantly reduced clinical service delivery time frame. Rapid orthodontic treatment and reduced apical root resorption are probably due to the transient osteopenia induced by the Cort surgery and inspired by

  13. Relationship between the total length of the stents and patients' quality of life after percutaneous coronary intervention.

    Science.gov (United States)

    Liu, Wei; Yang, Xuming; Dong, Pingshuan; Li, Zhijuan

    2015-01-01

    The aim of this study was to examine the relationship between the total length of the stents and the postoperative life quality of patients with multi-vessel coronary artery disease who undergo percutaneous coronary intervention (PCI). Using the short-form health survey (SF-36) items, we analyzed the data on the postoperative life quality of 166 patients with multi-vessel coronary artery disease who underwent percutaneous transluminal coronary intervention in the Department of Cardiology of the First Affiliated Hospital of Henan University of Science and Technology from September 2011 to September 2013. Follow-up was performed 6 months later. All of the dimensionalities, except general health and mental health, showed significantly higher scores after PCI. No significant relationships were observed between the total length of the stents and the postoperative life quality of patients with multi-vessel coronary artery disease who underwent PCI. PCI can effectively improve the postoperative life quality of patients; however, there was no significant relationship between the total length of the stents and postoperative life quality of patients.

  14. Vigorous root growth is a better indicator of early nutrient uptake than root hair traits in spring wheat grown under low fertility

    DEFF Research Database (Denmark)

    Wang, Yaosheng; Thorup-Kristensen, Kristian; Jensen, Lars Stoumann

    2016-01-01

    . Vigorous root growth, however, was a better indicator of early nutrient acquisition than RHL and RHD. Vigorous root growth and long and dense root hairs ensured efficient acquisition of macro- and micronutrients during early growth and a high root length to shoot dry matter ratio favored high macronutrient......A number of root and root hair traits have been proposed as important for nutrient acquisition. However, there is still a need for knowledge on which traits are most important in determining macro- and micronutrient uptake at low soil fertility. This study investigated the variations in root growth...... vigor and root hair length (RHL) and density (RHD) among spring wheat genotypes and their relationship to nutrient concentrations and uptake during early growth. Six spring wheat genotypes were grown in a soil with low nutrient availability. The root and root hair traits as well as the concentration...

  15. [Differences in root developmenly of winter wheat cultivars in Huang-Huai Plain, China].

    Science.gov (United States)

    Qiu, Xin-Qiang; Gao, Yang; Li, Xin-Qiang; Huang, Ling; Duan, Ai-Wang

    2012-07-01

    Selecting one presently popularized winter wheat cultivar (Zhengmai 9023) and two cultivars (Abo and Fengchan 3) introduced in the 1950s and 1960s in Huang-Huai Plain as test materials, and by using minirhizotron technique, this paper studied the live root length, root diameter distribution, and net root growth rate of the cultivars. Fine roots with a diameter from 0.05 mm to 0.25 mm occupied the majority of the whole root system, and the fine roots with a diameter less than 0.5 mm accounted for 98% of the live root length. The average root diameter varied with plant growth, the variation range being 0.15 - 0.22 mm, and no significant difference was observe among the cultivars. The live root length was significantly positively correlated root number, suggesting that root number was the main factor for the increase of live root length. The most vigorous growth period of the roots was from reviving to jointing stage, and Abo and Fengchan 3 had a longer period increased root vitality, as compared with Zhengmai 9023. For Zhengmai 9023, its fine roots with a diameter more than 0.1 mm had an increasing proportion after jointing stage, which was helpful for improving plant resistance, root activity, and grain-filling at late growth stages.

  16. Single-cell telomere-length quantification couples telomere length to meristem activity and stem cell development in Arabidopsis.

    Science.gov (United States)

    González-García, Mary-Paz; Pavelescu, Irina; Canela, Andrés; Sevillano, Xavier; Leehy, Katherine A; Nelson, Andrew D L; Ibañes, Marta; Shippen, Dorothy E; Blasco, Maria A; Caño-Delgado, Ana I

    2015-05-12

    Telomeres are specialized nucleoprotein caps that protect chromosome ends assuring cell division. Single-cell telomere quantification in animals established a critical role for telomerase in stem cells, yet, in plants, telomere-length quantification has been reported only at the organ level. Here, a quantitative analysis of telomere length of single cells in Arabidopsis root apex uncovered a heterogeneous telomere-length distribution of different cell lineages showing the longest telomeres at the stem cells. The defects in meristem and stem cell renewal observed in tert mutants demonstrate that telomere lengthening by TERT sets a replicative limit in the root meristem. Conversely, the long telomeres of the columella cells and the premature stem cell differentiation plt1,2 mutants suggest that differentiation can prevent telomere erosion. Overall, our results indicate that telomere dynamics are coupled to meristem activity and continuous growth, disclosing a critical association between telomere length, stem cell function, and the extended lifespan of plants. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Automated Root Tracking with "Root System Analyzer"

    Science.gov (United States)

    Schnepf, Andrea; Jin, Meina; Ockert, Charlotte; Bol, Roland; Leitner, Daniel

    2015-04-01

    identification number, the distance between branching point to the parent root base, the root length, the root radius and the nodes that belong to each individual root path. This information is relevant for the analysis of dynamic root system development as well as the parameterisation of root architecture models. Here, we show results of Root System Analyzer applied to analyse the root systems of wheat plants grown in rhizotrons. Different treatments with respect to soil moisture and apatite concentrations were used to test the effects of those conditions on root system development. Photographs of the root systems were taken at high spatial and temporal resolution and root systems are automatically tracked.

  18. Root anatomy, morphology, and longevity among root orders in Vaccinium corymbosum (Ericaceae).

    Science.gov (United States)

    Valenzuela-Estrada, Luis R; Vera-Caraballo, Vivianette; Ruth, Leah E; Eissenstat, David M

    2008-12-01

    Understanding root processes at the whole-plant or ecosystem scales requires an accounting of the range of functions within a root system. Studying root traits based on their branching order can be a powerful approach to understanding this complex system. The current study examined the highly branched root system of the ericoid plant, Vaccinium corymbosum L. (highbush blueberry) by classifying its root orders with a modified version of the morphometric approach similar to that used in hydrology for stream classification. Root anatomy provided valuable insight into variation in root function across orders. The more permanent portion of the root system occurred in 4th- and higher-order roots. Roots in these orders had radial growth; the lowest specific root length, N:C ratios, and mycorrhizal colonization; the highest tissue density and vessel number; and the coarsest root diameter. The ephemeral portion of the root system was mainly in the first three root orders. First- and 2nd-order roots were nearly anatomically identical, with similar mycorrhizal colonization and diameter, and also, despite being extremely fine, median lifespans were not very short (115-120 d; estimated with minirhizotrons). Our research underscores the value of examining root traits by root order and its implications to understanding belowground processes.

  19. Root distribution pattern and their contribution in photosynthesis and biomass in Jerusalem artichoke under drought

    International Nuclear Information System (INIS)

    Puangbut, D.; Vorasoot, N.

    2018-01-01

    Root length density and rooting depth have been established as drought resistant traits and these could be used as selection criteria for drought resistant genotype in many plant species. However, information on deep rooting and the root distribution pattern of Jerusalem artichoke under drought conditions is not well documented in the literature. The objective of this study was to investigate the root distribution pattern in Jerusalem artichoke genotypes under irrigated and drought conditions. This experiment was conducted within a greenhouse using rhizoboxes. Three Jerusalem artichoke genotypes were tested under two water regimes (irrigated and drought). A 2 × 3 factorial experiment was arranged in a randomized complete block design with three replications over two years. Data were recorded for root traits, photosynthesis and biomass at 30 days after imposing drought. The drought decreased root length, root surface area and root dry weight, while increased the root: shoot ratio, root distribution in the deeper soil and the percentage of root length at deeper in the soil, when compared to the irrigated conditions JA-5 and JA-60 showed high root length in the lower soil profile under drought conditions, indicating these genotypes could be identified as drought resistant genotype. The highest positive correlation was found between root length at deeper soil layer with relative water content (RWC), net photosynthetic rate (Pn) and biomass. It is expected that selection of Jerusalem artichoke with high root length coupled with maintaining high RWC and their promotion to Pn could improve the biomass and tuber yield under drought conditions. (author)

  20. Co-ordinated growth between aerial and root systems in young apple plants issued from in vitro culture.

    Science.gov (United States)

    Costes, E; García-Villanueva, E; Jourdan, C; Regnard, J L; Guédon, Y

    2006-01-01

    In several species exhibiting a rhythmic aerial growth, the existence of an alternation between root and shoot growth has been demonstrated. The present study aims to investigate the respective involvement of the emergence of new organs and their elongation in relation to this phenomenon and its possible genotypic variation in young apple plants. Two apple varieties, X6407 (recently named 'Ariane') and X3305 ('Chantecler' x 'Baujade'), were compared. Five plants per variety, issued from in vitro culture, were observed in minirhizotrons over 4 months. For each plant, root emergence and growth were observed twice per week. Growth rates were calculated for all roots with more than two segments and the branching density was calculated on primary roots. On the aerial part, the number of leaves, leaf area and total shoot length were observed weekly. No significant difference was observed between varieties in any of the final characteristics of aerial growth. Increase in leaf area and shoot length exhibited a 3-week rhythm in X3305 while a weaker signal was observed in Ariane. The primary root growth rate was homogeneous between the plants and likewise between the varieties, while their branching density differed significantly. Secondary roots emerged rhythmically, with a 3-week and a 2-week rhythm, respectively, in X3305 and 'Ariane'. Despite a high intra-variety variability, significant differences were observed between varieties in the secondary root life span and mean length. A synchronism between leaf emergence and primary root growth was highlighted in both varieties, while an opposition phase was observed between leaf area increments and secondary root emergence in X3305 only. A biological model of dynamics that summarizes the interactions between processes and includes the assumption of a feedback effect of lateral root emergence on leaf emergence is proposed.

  1. Changes in fine-root production, phenology and spatial distribution in response to N application in irrigated sweet cherry trees.

    Science.gov (United States)

    Artacho, Pamela; Bonomelli, Claudia

    2016-05-01

    Factors regulating fine-root growth are poorly understood, particularly in fruit tree species. In this context, the effects of N addition on the temporal and spatial distribution of fine-root growth and on the fine-root turnover were assessed in irrigated sweet cherry trees. The influence of other exogenous and endogenous factors was also examined. The rhizotron technique was used to measure the length-based fine-root growth in trees fertilized at two N rates (0 and 60 kg ha(-1)), and the above-ground growth, leaf net assimilation, and air and soil variables were simultaneously monitored. N fertilization exerted a basal effect throughout the season, changing the magnitude, temporal patterns and spatial distribution of fine-root production and mortality. Specifically, N addition enhanced the total fine-root production by increasing rates and extending the production period. On average, N-fertilized trees had a length-based production that was 110-180% higher than in control trees, depending on growing season. Mortality was proportional to production, but turnover rates were inconsistently affected. Root production and mortality was homogeneously distributed in the soil profile of N-fertilized trees while control trees had 70-80% of the total fine-root production and mortality concentrated below 50 cm depth. Root mortality rates were associated with soil temperature and water content. In contrast, root production rates were primarily under endogenous control, specifically through source-sink relationships, which in turn were affected by N supply through changes in leaf photosynthetic level. Therefore, exogenous and endogenous factors interacted to control the fine-root dynamics of irrigated sweet cherry trees. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Do illness rating systems predict discharge location, length of stay, and cost after total hip arthroplasty?

    Directory of Open Access Journals (Sweden)

    Sarah E. Rudasill, BA

    2018-06-01

    Conclusions: These findings suggest that although ASA classifications predict discharge location and SOI scores predict length of stay and total costs, other factors beyond illness rating systems remain stronger predictors of discharge for THA patients.

  3. Comparative transcriptomic analysis of roots of contrasting Gossypium herbaceum genotypes revealing adaptation to drought

    Directory of Open Access Journals (Sweden)

    Ranjan Alok

    2012-11-01

    Full Text Available Abstract Background Root length and its architecture govern the adaptability of plants to various stress conditions, including drought stress. Genetic variations in root growth, length, and architecture are genotypes dependent. In this study, we compared the drought-induced transcriptome of four genotypes of Gossypium herbaceum that differed in their drought tolerance adaptability. Three different methodologies, namely, microarray, pyrosequencing, and qRT–PCR, were used for transcriptome analysis and validation. Results The variations in root length and growth were found among four genotypes of G.herbaceum when exposed to mannitol-induced osmotic stress. Under osmotic stress, the drought tolerant genotypes Vagad and GujCot-21 showed a longer root length than did by drought sensitive RAHS-14 and RAHS-IPS-187. Further, the gene expression patterns in the root tissue of all genotypes were analyzed. We obtained a total of 794 differentially expressed genes by microarray and 104928 high-quality reads representing 53195 unigenes from the root transcriptome. The Vagad and GujCot-21 respond to water stress by inducing various genes and pathways such as response to stresses, response to water deprivation, and flavonoid pathways. Some key regulatory genes involved in abiotic stress such as AP2 EREBP, MYB, WRKY, ERF, ERD9, and LEA were highly expressed in Vagad and GujCot-21. The genes RHD3, NAP1, LBD, and transcription factor WRKY75, known for root development under various stress conditions, were expressed specifically in Vagad and GujCot-21. The genes related to peroxidases, transporters, cell wall-modifying enzymes, and compatible solutes (amino acids, amino sugars, betaine, sugars, or sugar alcohols were also highly expressed in Vagad and Gujcot-21. Conclusion Our analysis highlights changes in the expression pattern of genes and depicts a small but highly specific set of drought responsive genes induced in response to drought stress. Some of these

  4. Comparison of the Accuracy of Root ZX and Novapex with Radiography: an in Vivo Study

    Directory of Open Access Journals (Sweden)

    Amir Mohamad Mahabadi

    2012-02-01

    Full Text Available Background and Aims: Working length determination and remaining this length is of great importance in root canal therapy. Recently, electronic apex locators are being used to determine working length and decrease the number of radiographs. The purpose of this study was to compare the sensitivity of Root ZX and Novapex electronic apex locators with radiography in a clinical study. Materials and Methods: In this study, 73 single-canalled teeth of the patients referred to the endodontic department of the Yazd Dental School were evaluated. The access cavity was prepared and working length of the root canals were measured by using the apex locators: Root ZX and Novapex. The file was placed in the root canal and a periapical radiograph was taken using parallel technique. The working lengths obtained by apex locators were recorded and compared with those of radiographs. The data were analyzed by Pearsons correlation coefficient, Wilcoxon test and paired t-test. Results: The exact measurement without any fault was 46.6% for Root ZX and 20.5% for Novapex compared to radiography. In the range of 0.5 mm fault, the results were 91.8% for Root ZX and 64.4% for Novapex compared to radiographic measurements. The difference between the average of the measured lengths by Root ZX and radiography was not significant (P=0.17. On the other hand, the results showed significant difference between the average of the measured lengths by Novapex and radiography (P=0.017. The difference between two apex locators was not significant (P=0.061. Conclusion: Root ZX and Novapex with high accuracy are useful for determining working length of the root canals in pregnant patients with special anatomic conditions and patients with muscle disharmony. Therefore, the use of these apex locators combined with radiography is recommended in root canal treatment.

  5. Foxtail Millet [Setaria italica (L. Beauv.] Grown under Low Nitrogen Shows a Smaller Root System, Enhanced Biomass Accumulation, and Nitrate Transporter Expression

    Directory of Open Access Journals (Sweden)

    Faisal Nadeem

    2018-02-01

    Full Text Available Foxtail millet (FM [Setaria italica (L. Beauv.] is a grain and forage crop well adapted to nutrient-poor soils. To date little is known how FM adapts to low nitrogen (LN at the morphological, physiological, and molecular levels. Using the FM variety Yugu1, we found that LN led to lower chlorophyll contents and N concentrations, and higher root/shoot and C/N ratios and N utilization efficiencies under hydroponic culture. Importantly, enhanced biomass accumulation in the root under LN was in contrast to a smaller root system, as indicated by significant decreases in total root length; crown root number and length; and lateral root number, length, and density. Enhanced carbon allocation toward the root was rather for significant increases in average diameter of the LN root, potentially favorable for wider xylem vessels or other anatomical alterations facilitating nutrient transport. Lower levels of IAA and CKs were consistent with a smaller root system and higher levels of GA may promote root thickening under LN. Further, up-regulation of SiNRT1.1, SiNRT2.1, and SiNAR2.1 expression and nitrate influx in the root and that of SiNRT1.11 and SiNRT1.12 expression in the shoot probably favored nitrate uptake and remobilization as a whole. Lastly, more soluble proteins accumulated in the N-deficient root likely as a result of increases of N utilization efficiencies. Such “excessive” protein-N was possibly available for shoot delivery. Thus, FM may preferentially transport carbon toward the root facilitating root thickening/nutrient transport and allocate N toward the shoot maximizing photosynthesis/carbon fixation as a primary adaptive strategy to N limitation.

  6. Foxtail Millet [Setaria italica (L.) Beauv.] Grown under Low Nitrogen Shows a Smaller Root System, Enhanced Biomass Accumulation, and Nitrate Transporter Expression.

    Science.gov (United States)

    Nadeem, Faisal; Ahmad, Zeeshan; Wang, Ruifeng; Han, Jienan; Shen, Qi; Chang, Feiran; Diao, Xianmin; Zhang, Fusuo; Li, Xuexian

    2018-01-01

    Foxtail millet (FM) [ Setaria italica (L.) Beauv.] is a grain and forage crop well adapted to nutrient-poor soils. To date little is known how FM adapts to low nitrogen (LN) at the morphological, physiological, and molecular levels. Using the FM variety Yugu1, we found that LN led to lower chlorophyll contents and N concentrations, and higher root/shoot and C/N ratios and N utilization efficiencies under hydroponic culture. Importantly, enhanced biomass accumulation in the root under LN was in contrast to a smaller root system, as indicated by significant decreases in total root length; crown root number and length; and lateral root number, length, and density. Enhanced carbon allocation toward the root was rather for significant increases in average diameter of the LN root, potentially favorable for wider xylem vessels or other anatomical alterations facilitating nutrient transport. Lower levels of IAA and CKs were consistent with a smaller root system and higher levels of GA may promote root thickening under LN. Further, up-regulation of SiNRT1.1, SiNRT2.1, and SiNAR2.1 expression and nitrate influx in the root and that of SiNRT1.11 and SiNRT1.12 expression in the shoot probably favored nitrate uptake and remobilization as a whole. Lastly, more soluble proteins accumulated in the N-deficient root likely as a result of increases of N utilization efficiencies. Such "excessive" protein-N was possibly available for shoot delivery. Thus, FM may preferentially transport carbon toward the root facilitating root thickening/nutrient transport and allocate N toward the shoot maximizing photosynthesis/carbon fixation as a primary adaptive strategy to N limitation.

  7. Comparison of root canal lathing measurement by conventional and digital radiology

    International Nuclear Information System (INIS)

    Mitrova, N.; Slavik, J.; Cecetkova, A.; Jenca, A.; Hanusinova, V.; Ondrasovicova, J.

    2006-01-01

    A correct working length is a critical factor within the endodontic treatment. The length of the root canal can be measured by different methods. The aim of this study was to compare methods used for measuring the length of root canals using conventional and digital radiology. The measurement was provided in both - in vitro and in vivo conditions. (authors)

  8. Determination of the Proportion of Total Soil Extracellular Acid Phosphomonoesterase (E.C. 3.1.3.2 Activity Represented by Roots in the Soil of Different Forest Ecosystems

    Directory of Open Access Journals (Sweden)

    Klement Rejsek

    2012-01-01

    Full Text Available The aim of this study is to present a new method for determining the root-derived extracellular acid phosphomonoesterase (EAPM activity fraction within the total EAPM activity of soil. EAPM activity was determined for roots, organic and mineral soil. Samples were collected using paired PVC cylinders, inserted to a depth of 15 cm, within seven selected forest stands. Root-derived EAPM formed between 4 and18% of the total EAPM activity of soil from forests of differing maturity. A new approach, presented in this work, enables separation of root-derived EAPM activity from total soil EAPM. Separation of root-derived EAPM from soil provides a better understanding of its role in P-cycling in terrestrial ecosystems. The method presented in this work is a first step towards the separation of root- and microbe-derived EAPM in soils, which are thought to possess different kinetic properties and different sensitivity to environmental change.

  9. Effect of ionizing radiation and indole butyric acid on rooting of olive cuttings

    International Nuclear Information System (INIS)

    Al-Bachir, Mahfouz

    1993-12-01

    This study was performed to investigate the effects of indole butyric acid (IBA) (2000 and 4000 ppm), low doses of gamma irradiation (2,4, and 6 Gy), combined treatment of IBA followed by irradiation, and irradiation followed by IBA on olive cuttings (Variety Khodairi). Rooting percentage, callus formation, vegetative growth root number, and the length of the roots were measured after 100 days of planting. The results indicated that IBA treatments in both concentrations increased the callus formation, rooting, vegetative growth, and the number and length of the roots. Low doses of gamma irradiation had no effects on rooting percentage in comparison with the hormonal treatments. Callus formation, rooting, vegetative growth, and length of the root of cuttings produced in 1990 were better than those produced in 1991, and cuttings produced in January were better than those produced in March and October. (author). 16 refs., 15 tabs

  10. Coarse root topology of Norway spruce (Picea abies) and its effects on slope stability

    Science.gov (United States)

    Lith, Aniek; Schmaltz, Elmar; Bogaard, Thom; Keesstra, Saskia

    2017-04-01

    The structural distribution of coarse roots and its beneficial effects on soil reinforcement has widely been assessed. However, it is still not fully understood how topological features of coarse roots (e.g. branching patterns) are affected by slope inclination and further influence the ability of young trees to reinforce soil. This study aims to analyse empirically the impact of slope gradient on the topological development of coarse roots and thus to assess its effects on soil reinforcement. We performed root system excavations on two young Picea abies: tree A on a gently inclined plane (β ≈ 12°) where slope failures are not expected; tree B on a slope (β ≈ 35°) with failure potential. The diameter (d) of the segments between distinct root nodes (root ends, branching locations, direction changes and attachments to stem) of coarse roots (d > 2mm) were measured in situ. The spatial coordinates (x,y,z) of the nodes and surface were measured on a plane raster grid, from which segment length (ls), direction and inclination towards the surface (βr) were derived. Roots and segments were classified into laterals (βr classifications (FSC), to obtain quantitative relations between the topological order and number of segments, total and average ls. The maximal root cohesion (cr) of each segment was assessed using material specific tensile forces (Tr), root area ratio (RAR) and βr, assuming that a potential slip surface would cross the root system parallel to the slope. Laterals depicted the majority of roots (57 %) for tree A orientated rather in upslope direction (76.8 %), whereas tree B showed mostly obliques (54 %) orientated rather in downslope direction (55.4 %). Vertical roots were scarcely observable for both trees. DSC showed a high r2 (> 0.84) for the segments and ls. FSC showed high r2 (> 0.95) for the number of segments and the total length. RAR values of tree B are distributed rather upslope (76.8 % of RARtot), compared to 44.5 % of RARtot for tree A

  11. Root proliferation in decaying roots and old root channels: A nutrient conservation mechanism in oligotrophic mangrove forests?

    Science.gov (United States)

    McKee, K.L.

    2001-01-01

    1. In oligotrophic habitats, proliferation of roots in nutrient-rich microsites may contribute to overall nutrient conservation by plants. Peat-based soils on mangrove islands in Belize are characterized by the presence of decaying roots and numerous old root channels (0.1-3.5 cm diameter) that become filled with living and highly branched roots of Rhizophora mangle and Avicennia germinans. The objectives of this study were to quantify the proliferation of roots in these microsites and to determine what causes this response. 2. Channels formed by the refractory remains of mangrove roots accounted for only 1-2% of total soil volume, but the proportion of roots found within channels varied from 9 to 24% of total live mass. Successive generations of roots growing inside increasingly smaller root channels were also found. 3. When artificial channels constructed of PVC pipe were buried in the peat for 2 years, those filled with nutrient-rich organic matter had six times more roots than empty or sand-filled channels, indicating a response to greater nutrient availability rather than to greater space or less impedance to root growth. 4. Root proliferation inside decaying roots may improve recovery of nutrients released from decomposing tissues before they can be leached or immobilized in this intertidal environment. Greatest root proliferation in channels occurred in interior forest zones characterized by greater soil waterlogging, which suggests that this may be a strategy for nutrient capture that minimizes oxygen losses from the whole root system. 5. Improved efficiency of nutrient acquisition at the individual plant level has implications for nutrient economy at the ecosystem level and may explain, in part, how mangroves persist and grow in nutrient-poor environments.

  12. Anatomic investigation of the lumbosacral nerve roots and dorsal root ganglia by MRI

    International Nuclear Information System (INIS)

    Hasegawa, Toru; Fuse, Kenzo; Mikawa, Yoshihiro; Watanabe, Ryo

    1995-01-01

    The morphology of the lumbosacral nerve roots and dorsal root ganglia (DRG) was examined by using magnetic resonance imaging (MRI) in 11 healthy male volunteers aged 20-40 years. One hundred and twenty-three nerve roots (15 at the L1 level, 22 each at the L2-L5 levels, and 20 at the S1 level) were examined in terms of the position and angle of the bifurcation of the nerve roots, length of the nerve root, and the position and width of DRG. The nerve roots at the lower levels showed more cephalad position and smaller angle of bifurcation on MRI. The distance from the bifurcation of nerve roots to the cephalad edge of DRG was significantly longer in the upper root levels and was significantly shorter in the L5 roots than the S1 roots. The positions of DRG at the S1 level tended to become cephalad. DRG that was positioned toward more caudal direction was larger and more elliptic. MRI provided useful information concerning morphology and anatomical position of nerve roots and DRG, thereby allowing accurate diagnosis and the determination of surgical indications. (N.K.)

  13. Root resorption during orthodontic treatment with Invisalign®: a radiometric study

    Directory of Open Access Journals (Sweden)

    Giulia Gay

    2017-05-01

    Full Text Available Abstract Background Root resorption (RR is described as a permanent loss of tooth structure from the root apex. Many reports in the literature indicate that orthodontically treated patients are more likely to have severe apical root shortening, interesting mostly maxillary, followed by mandibular incisors. The aim of the study was to investigate the incidence and severity of RR in adult patients treated with aligners. The study group consisted of 71 class I adult healthy patients (mean age 32.8 ± 12.7 treated with aligners (Invisalign®, Align Technologies, Santa Clara, CA, USA. All incisors, canines, upper first premolars, and first molars were assessed. Root and crown lengths of 1083 teeth were measured in panoramic radiographs at the beginning (T0 and at the end (T1 of clear aligner therapy. Individual root-crown ratio (RCR of each tooth and therefore the relative changes of RCR (rRCR were determined. A decrease of rRCR was assessed as a reduction of the root length during treatment. Results All patients had a minimum of one teeth affected with a reduction of root length, on average 6.38 ± 2.28 teeth per patient. Forty one, 81% of the 1083, measured teeth presented a reduction of the pre-treatment root length. A reduction in percentage of >0% up to 10% was found in 25.94% (n = 281, a distinct reduction of >10% up to 20% in 12.18% (n = 132 of the sample. 3.69% (n = 40 of the teeth were affected with a considerable reduction (>20%. Conclusions Orthodontic treatment with Invisalign® aligners could lead to RR. However, its incidence resulted to be very similar to that described for orthodontic light forces, with an average percentage of RR < 10% of the original root length.

  14. Root resorption during orthodontic treatment with Invisalign®: a radiometric study.

    Science.gov (United States)

    Gay, Giulia; Ravera, Serena; Castroflorio, Tommaso; Garino, Francesco; Rossini, Gabriele; Parrini, Simone; Cugliari, Giovanni; Deregibus, Andrea

    2017-12-01

    Root resorption (RR) is described as a permanent loss of tooth structure from the root apex. Many reports in the literature indicate that orthodontically treated patients are more likely to have severe apical root shortening, interesting mostly maxillary, followed by mandibular incisors. The aim of the study was to investigate the incidence and severity of RR in adult patients treated with aligners. The study group consisted of 71 class I adult healthy patients (mean age 32.8 ± 12.7) treated with aligners (Invisalign®, Align Technologies, Santa Clara, CA, USA). All incisors, canines, upper first premolars, and first molars were assessed. Root and crown lengths of 1083 teeth were measured in panoramic radiographs at the beginning (T0) and at the end (T1) of clear aligner therapy. Individual root-crown ratio (RCR) of each tooth and therefore the relative changes of RCR (rRCR) were determined. A decrease of rRCR was assessed as a reduction of the root length during treatment. All patients had a minimum of one teeth affected with a reduction of root length, on average 6.38 ± 2.28 teeth per patient. Forty one, 81% of the 1083, measured teeth presented a reduction of the pre-treatment root length. A reduction in percentage of >0% up to 10% was found in 25.94% (n = 281), a distinct reduction of >10% up to 20% in 12.18% (n = 132) of the sample. 3.69% (n = 40) of the teeth were affected with a considerable reduction (>20%). Orthodontic treatment with Invisalign® aligners could lead to RR. However, its incidence resulted to be very similar to that described for orthodontic light forces, with an average percentage of RR root length.

  15. Accuracy of working length determination with root ZX apex locator ...

    African Journals Online (AJOL)

    Jane

    2011-07-18

    Jul 18, 2011 ... generation of electronic apex locators (EALs), called root. ZX (J. Morita Co., Tustin, .... dentinocemento junction. Dent Items Interest, 50: 855-857. ... apex locator with an automatic compensation circuit. J. Endod. 28: 706-709.

  16. Correlation of quinone reductase activity and allyl isothiocyanate formation among different genotypes and grades of horseradish roots.

    Science.gov (United States)

    Ku, Kang-Mo; Jeffery, Elizabeth H; Juvik, John A; Kushad, Mosbah M

    2015-03-25

    Horseradish (Armoracia rusticana) is a perennial crop and its ground root tissue is used in condiments because of the pungency of the glucosinolate (GS)-hydrolysis products allyl isothiocyanate (AITC) and phenethyl isothiocyanate (PEITC) derived from sinigrin and gluconasturtiin, respectively. Horseradish roots are sold in three grades: U.S. Fancy, U.S. No. 1, and U.S. No. 2 according to the USDA standards. These grading standards are primarily based on root diameter and length. There is little information on whether root grades vary in their phytochemical content or potential health promoting properties. This study measured GS, GS-hydrolysis products, potential anticancer activity (as quinone reductase inducing activity), total phenolic content, and antioxidant activities from different grades of horseradish accessions. U.S. Fancy showed significantly higher sinigrin and AITC concentrations than U.S. No. 1 ,whereas U.S. No. 1 showed significantly higher concentrations of 1-cyano 2,3-epithiopropane, the epithionitrile hydrolysis product of sinigrin, and significantly higher total phenolic concentrations than U.S. Fancy.

  17. Root-type-specific plasticity in response to localized high nitrate supply in maize (Zea mays).

    Science.gov (United States)

    Yu, Peng; Hochholdinger, Frank; Li, Chunjian

    2015-10-01

    Shoot-borne roots contribute to most of the nutrient uptake throughout the life cycle of maize (Zea mays). Compared with numerous studies with embryonic roots, detailed information on the phenotypic plasticity of shoot-borne roots in response to a heterogeneous nitrogen supply is scarce. The present study therefore provides a comprehensive profile of fine-scale plastic responses of distinct root types to localized high nitrate supply. Seedlings of the maize inbred line B73 were grown in split-root systems. The anatomy and morphological plasticity of the primary root and the roots initiated from the 2nd, 5th and 7th shoot nodes, and their lateral roots, were studied in response to local high nitrate supply to one side of the root system. In contrast to the insensitivity of axial roots, local high nitrate supply increased the length of 1st-order lateral roots on the primary root and the three whorls of shoot-borne roots at different growth stages, and increased the density of 1st-order lateral roots on the 7th shoot-borne root after silking. The length and density of 2nd-order lateral roots on the three whorls of shoot-borne roots displayed a more flexible response to local high nitrate than 1st-order lateral roots. Root diameter and number, and total area and diameter of metaxylem vessels increased from the primary root to early and then later developed shoot-borne roots, which showed a positive relationship with shoot growth and N accumulation. Maize axial roots and lateral roots responded differently to local high nitrate, and this was related to their function. The extent of morphological plasticity of lateral roots in response to local high nitrate depended on the initiation time of the shoot-borne roots on which the lateral roots developed. Morphological plasticity was higher on 2nd-order than on 1st-order lateral roots. The results suggest that higher order lateral root branching might be a potential target for genetic improvement in future maize breeding.

  18. The length-weight and length-length relationships of bluefish, Pomatomus saltatrix (Linnaeus, 1766 from Samsun, middle Black Sea region

    Directory of Open Access Journals (Sweden)

    Melek Özpiçak

    2017-10-01

    Full Text Available In this study, length-weight relationship (LWR and length-length relationship (LLR of bluefish, Pomatomus saltatrix were determined. A total of 125 specimens were sampled from Samsun, the middle Black Sea in 2014 fishing season. Bluefish specimens were monthly collected from commercial fishing boats from October to December 2014. All captured individuals (N=125 were measured to the nearest 0.1 cm for total, fork and standard lengths. The weight of each fish (W was recorded to the nearest 0.01 g. According to results of analyses, there were no statistically significant differences between sexes in term of length and weight (P˃0.05. The minimum and maximum total, fork and standard lengths of bluefish ranged between 13.5-23.6 cm, 12.50-21.80 cm and 10.60-20.10 cm, respectively. The equation of length-weight relationship were calculated as W=0.008TL3.12 (r2>0.962. Positive allometric growth was observed for bluefish (b>3. Length-length relationship was also highly significant (P<0.001 with coefficient of determination (r2 ranging from 0.916 to 0.988.

  19. The length-weight and length-length relationships of bluefish, Pomatomus saltatrix (Linnaeus, 1766) from Samsun, middle Black Sea region

    OpenAIRE

    Özpiçak, Melek; Saygın, Semra; Polat, Nazmi

    2017-01-01

    In this study, length-weight relationship (LWR) and length-length relationship (LLR) of bluefish,Pomatomus saltatrix were determined. A total of 125 specimens were sampled from Samsun, themiddle Black Sea in 2014 fishing season. Bluefish specimens were monthly collected fromcommercial fishing boats from October to December 2014. All captured individuals (N=125) weremeasured to the nearest 0.1 cm for total, fork and standard lengths. The weight of each fish (W)was recorded to the nearest 0.01 ...

  20. Assessment of periapical health, quality of root canal filling, and ...

    African Journals Online (AJOL)

    Sixty three teeth were found to have short root canal fillings, whereas 74 teeth had adequate root canal fillings, and the remaining 10 teeth had over extended root canal filling. A significant correlation was observed between the length of root filling and apical periodontitis (P = 0,023). Inadequately dense root canal filling was ...

  1. Relationship between dental anomalies and orthodontic root resorption of upper incisors.

    Science.gov (United States)

    Van Parys, Katrien; Aartman, Irene H A; Kuitert, Reinder; Zentner, Andrej

    2012-10-01

    The aim of this study was to examine the potential relationship between the occurrence of orthodontic root resorption and presence of dental anomalies such as tooth agenesis and pipette-shaped roots. Dental anomalies and root resorption were assessed on dental panoramic tomographs (DPT) of 88 subjects, 27 males and 61 females, mean age 28.4 (SD = 11.3 years), selected from orthodontic patients on the basis of the following exclusion criteria: previous fixed appliance treatment, bad quality of the DPTs and no visibility of the periodontal ligament of every tooth, and younger than 15 years of age at the onset of treatment with fixed edgewise appliance lasting at least 18 months. A pipette-shaped root was identified as defined by a drawing. Tooth agenesis was assessed on DPTs and from subjects' dental history. Root resorption was calculated as the difference between the root length before and after treatment, with and without a correction factor (crown length post-treatment/crown length pre-treatment). If one of the four upper incisors showed root resorption of ≥2.3 mm with both formulas, the patient was scored as having root resorption. Chi-square tests indicated that there was no relationship between orthodontic root resorption and agenesis (P = 0.885) nor between orthodontic root resorption and pipette-shaped roots (P = 0.800). There was no relationship between having one of the anomalies and root resorption either (P = 0.750). In the present study, it was not possible to confirm on DPTs a relationship between orthodontic root resorption and dental anomalies, such as agenesis and pipette-shaped roots.

  2. Root resistance to cavitation is accurately measured using a centrifuge technique.

    Science.gov (United States)

    Pratt, R B; MacKinnon, E D; Venturas, M D; Crous, C J; Jacobsen, A L

    2015-02-01

    Plants transport water under negative pressure and this makes their xylem vulnerable to cavitation. Among plant organs, root xylem is often highly vulnerable to cavitation due to water stress. The use of centrifuge methods to study organs, such as roots, that have long vessels are hypothesized to produce erroneous estimates of cavitation resistance due to the presence of open vessels through measured samples. The assumption that roots have long vessels may be premature since data for root vessel length are sparse; moreover, recent studies have not supported the existence of a long-vessel artifact for stems when a standard centrifuge technique was used. We examined resistance to cavitation estimated using a standard centrifuge technique and compared these values with native embolism measurements for roots of seven woody species grown in a common garden. For one species we also measured vulnerability using single-vessel air injection. We found excellent agreement between root native embolism and the levels of embolism measured using a centrifuge technique, and with air-seeding estimates from single-vessel injection. Estimates of cavitation resistance measured from centrifuge curves were biologically meaningful and were correlated with field minimum water potentials, vessel diameter (VD), maximum xylem-specific conductivity (Ksmax) and vessel length. Roots did not have unusually long vessels compared with stems; moreover, root vessel length was not correlated to VD or to the vessel length of stems. These results suggest that root cavitation resistance can be accurately and efficiently measured using a standard centrifuge method and that roots are highly vulnerable to cavitation. The role of root cavitation resistance in determining drought tolerance of woody species deserves further study, particularly in the context of climate change. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Multi-walled carbon nanotubes can enhance root elongation of wheat (Triticum aestivum) plants

    International Nuclear Information System (INIS)

    Wang Xiuping; Han Heyou; Liu Xueqin; Gu Xiaoxu; Chen Kun; Lu Donglian

    2012-01-01

    The potential effects of oxidized multi-walled carbon nanotubes (o-MWCNTs) with a length ranging from 50 to 630 nm on the development and physiology of wheat plants were evaluated by examining their effects on seed germination, root elongation, stem length, and vegetative biomass at a concentration ranging from 10 to 160 μg/mL in the plant. Results indicated that after 7 days of exposure to the o-MWCNTs medium, faster root growth and higher vegetative biomass were observed, but seed germination and stem length did not show any difference as compared with controls. Moreover, a physiological study was conducted at cellular level using a traditional physiological approach to evidence the possible alterations in morphology, the cell length of root zone, and the dehydrogenase activity of seedlings. Transmission electron microscopy images revealed that o-MWCNTs could penetrate the cell wall and enter the cytoplasm after being taken up by roots. The cell length of root zone for the seedlings germinated and grown in the o-MWCNTs (80 μg/mL) medium increased by 1.4-fold and a significant concentration-dependent increase in the dehydrogenase activity for the o-MWCNT-treated wheat seedlings was detected. These findings suggest that o-MWCNTs can significantly promote cell elongation in the root system and increase the dehydrogenase activity, resulting in faster root growth and higher biomass production.

  4. Multi-walled carbon nanotubes can enhance root elongation of wheat (Triticum aestivum) plants

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xiuping; Han Heyou, E-mail: hyhan@mail.hzau.edu.cn; Liu Xueqin; Gu Xiaoxu; Chen Kun; Lu Donglian [Huazhong Agricultural University, College of Science, State Key Laboratory of Agricultural Microbiology, Institute of Chemical Biology (China)

    2012-06-15

    The potential effects of oxidized multi-walled carbon nanotubes (o-MWCNTs) with a length ranging from 50 to 630 nm on the development and physiology of wheat plants were evaluated by examining their effects on seed germination, root elongation, stem length, and vegetative biomass at a concentration ranging from 10 to 160 {mu}g/mL in the plant. Results indicated that after 7 days of exposure to the o-MWCNTs medium, faster root growth and higher vegetative biomass were observed, but seed germination and stem length did not show any difference as compared with controls. Moreover, a physiological study was conducted at cellular level using a traditional physiological approach to evidence the possible alterations in morphology, the cell length of root zone, and the dehydrogenase activity of seedlings. Transmission electron microscopy images revealed that o-MWCNTs could penetrate the cell wall and enter the cytoplasm after being taken up by roots. The cell length of root zone for the seedlings germinated and grown in the o-MWCNTs (80 {mu}g/mL) medium increased by 1.4-fold and a significant concentration-dependent increase in the dehydrogenase activity for the o-MWCNT-treated wheat seedlings was detected. These findings suggest that o-MWCNTs can significantly promote cell elongation in the root system and increase the dehydrogenase activity, resulting in faster root growth and higher biomass production.

  5. Prevalence of apical periodontitis and quality of root canal fillings in population of Zagreb, Croatia: a cross-sectional study

    Science.gov (United States)

    Matijević, Jurica; Čižmeković Dadić, Tina; Prpić Mehičić, Goranka; Anić, Ivica; Šlaj, Mladen; Jukić Krmek, Silvana

    2011-01-01

    Aim To determine the prevalence of apical periodontitis and assess the quality of endodontic fillings in the population of the city of Zagreb, Croatia. Methods A total of 1462 orthopantomograms from new patients at 6 different dental practices was analyzed during 2006 and 2007. The presence of periapical lesions was determined by using the periapical index score (PAI). The quality of endodontic fillings was assessed according to the filling length and homogeinicity. Data were analyzed using t test and ANOVA with Scheffe post-hoc test. Results There were 75.9% of participants with endodontically treated teeth and 8.5% of all teeth were endodontically treated. Only 34.2% of endodontically treated roots had adequate root canal filling length, while 36.2% of root canal fillings had homogenous appearance. From the total number of teeth with intracanal post, 17.5% had no visible root canal filling. Using PAI 3 as a threshold value for apical periodontitis, periapical lesions were detected in 8.5% of teeth. Adequate quality of root canal fillings was associated with a lower prevalence of periapical lesions. Conclusion We found a large proportion of endodontically treated teeth with apical periodontitis and a correlation between the quality of endodontic filling and the prevalence of periapical lesions. This all suggests that it is necessary to improve the quality of endodontic treatment in order to reduce the incidence and prevalence of apical periodontitis. PMID:22180266

  6. Long-term effects of deep soil loosening on root distribution and soil physical parameters in compacted lignite mine soils

    Science.gov (United States)

    Badorreck, Annika; Krümmelbein, Julia; Raab, Thomas

    2015-04-01

    Soil compaction is a major problem of soils on dumped mining substrates in Lusatia, Germany. Deep ripping and cultivation of deep rooting plant species are considered to be effective ways of agricultural recultivation. Six years after experiment start, we studied the effect of initial deep soil loosening (i.e. down to 65 cm) on root systems of rye (Secale cereale) and alfalfa (Medicago sativa) and on soil physical parameters. We conducted a soil monolith sampling for each treatment (deep loosened and unloosened) and for each plant species (in three replicates, respectively) to determine root diameter, length density and dry mass as well as soil bulk density. Further soil physical analysis comprised water retention, hydraulic conductivity and texture in three depths. The results showed different reactions of the root systems of rye and alfalfa six years after deep ripping. In the loosened soil the root biomass of the rye was lower in depths of 20-40 cm and the root biomass of alfalfa was also decreased in depths of 20-50 cm together with a lower root diameter for both plant species. Moreover, total and fine root length density was higher for alfalfa and vice versa for rye. The soil physical parameters such as bulk density showed fewer differences, despite a higher bulk density in 30-40cm for the deep loosened rye plot which indicates a more pronounced plough pan.

  7. Ethylene: a regulator of root architectural responses to soil phosphorus availability

    NARCIS (Netherlands)

    Borch, K.; Bouma, T.J.; Lynch, J.P.; Brown, K.M.

    1999-01-01

    The involvement of ethylene in root architectural responses to phosphorus availability was investigated in common bean (Phaseolus vulgaris L,) plants grown with sufficient and deficient phosphorus. Although phosphorus deficiency reduced root mass and lateral root number, main root length was

  8. Contribution of cone beam computed tomography to the detection of apical root resorption after orthodontic treatment in root-filled and vital teeth.

    Science.gov (United States)

    Castro, Iury; Valladares-Neto, José; Estrela, Carlos

    2015-09-01

    To investigate whether root-filled teeth are similar to vital pulp teeth in terms of apical root resorption (ARR) after orthodontic treatment. An original sample of cone beam computed tomography (CBCT) images of 1256 roots from 30 orthodontic patients were analyzed. The inclusion criteria demanded root-filled teeth and their contralateral vital teeth, while teeth with history of trauma had to be excluded to comply with exclusion criteria. CBCT images of root-filled teeth were compared before and after orthodontic treatment in a split-mouth design study. Tooth measurements were made with multiplanar reconstruction using axial-guided navigation. The statistical difference between the treatment effects was compared using the paired t-test. Twenty posterior root-filled teeth and their contralaterals with vital pulp were selected before orthodontic treatment from six adolescents (two boys and four girls; mean [SD] age 12.8 [1.8] years). No differences were detected between filled and vital root lengths before treatment (P  =  .4364). The mean differences in root length between preorthodontic and postorthodontic treatment in filled- and vital roots were -0.30 mm and -0.16 mm, respectively, without any statistical difference (P  =  .4197) between them. There appears to be no increase in ARR after orthodontic treatment in root-filled teeth with no earlier ARR.

  9. In Vitro Comparative Study of the Working Length Determination with Radiovisiography and Conventional Radiography in Dilacerated Canals

    Directory of Open Access Journals (Sweden)

    Ali Bagherpour

    2015-06-01

    Full Text Available Introduction: The aim of this study was to compare digital and conventional radiography in determining the working length of dilacerated canals.Methods: Thirty nine human extracted single-rooted teeth with root curvature more than 35 degrees were included in this study. After access preparation, a file was inserted into the canal and advanced until the file tip was visualized at the foramen. With measurement of the file length using a millimeter ruler, true canal length was determined for each canal. Then, teeth were mounted in acrylic blocks and canal length was estimated by using on-screen digital radiography with both 3- and 6-clicks measurement and from conventional radiography by conforming a preserved file on the image of the root canal.Results: There were no significant differences in measurement accuracy between the true canal length and conventional radiographic length, but there were significant difference between both digital radiographic techniques with true canal length. There was no significant correlation between root curvature and canal length estimation error of studied methods.Conclusion: In dilacerated canals, the accuracy of determination of working length by using conventional radiography is higher than digital radiography

  10. In vitro radiographic determination of distances from working length files to root ends comparing Kodak RVG 6000, Schick CDR, and Kodak insight film.

    Science.gov (United States)

    Radel, Robert T; Goodell, Gary G; McClanahan, Scott B; Cohen, Mark E

    2006-06-01

    Previous studies suggest that digital and film-based radiography are similar for endodontic measurements. This study compared the accuracy and acceptability of measured distances from the tips of size #10 and #15 files to molar root apices in cadaver jaw sections using the newly developed Kodak RVG 6000, and the Schick CDR digital systems to digitized Kodak film. Standardized images were taken of files placed 0.5 to 1.5 mm short of true radiographic lengths. Images were imported into Adobe PhotoShop 7.0, thereby blinding observers who measured distances from files to root apices and assessed images for clarity (acceptability). Repeated measures ANOVA and Tukey-Kramer post hoc tests demonstrated that Kodak RVG 6000 images with enhanced contrast produced significantly less measurement error than unenhanced contrast Schick CDR images (p Kodak RVG 6000 system provided the best overall images.

  11. Reducing Length of Stay, Direct Cost, and Readmissions in Total Joint Arthroplasty Patients With an Outcomes Manager-Led Interprofessional Team.

    Science.gov (United States)

    Arana, Melissa; Harper, Licia; Qin, Huanying; Mabrey, Jay

    The purpose of this quality improvement project was to determine whether an outcomes manager-led interprofessional team could reduce length of stay and direct cost without increasing 30-day readmission rates in the total joint arthroplasty patient population. The goal was to promote interprofessional relationships combined with collaborative practice to promote coordinated care with improved outcomes. Results from this project showed that length of stay (total hip arthroplasty [THA] reduced by 0.4 days and total knee arthroplasty [TKA] reduced by 0.6 days) and direct cost (THA reduced by $1,020 per case and TKA reduced by $539 per case) were significantly decreased whereas 30-day readmission rates of both populations were not significantly increased.

  12. Reducing the length of hospital stay after total knee arthroplasty: influence of femoral and sciatic nerve block.

    Science.gov (United States)

    Carvalho Júnior, Lúcio Honório de; Temponi, Eduardo Frois; Paganini, Vinícius Oliveira; Costa, Lincoln Paiva; Soares, Luiz Fernando Machado; Gonçalves, Matheus Braga Jacques

    2015-01-01

    the aim of this study is to evaluate the change in length of hospital stay postoperatively for Total Knee Arthroplasty after using femoral and sciatic nerve block. the medical records of 287 patients were evaluated, taking into account the number of hours of admission, the percentage and the reason for re-hospitalization within 30 days, as well as associated complications. All patients were divided into two groups according or not to whether they were admitted to ICU or not. During the years 2009 and 2010, isolated spinal anesthesia was the method used in the procedure. From 2011 on, femoral and sciatic nerve blocking was introduced. between the years 2009 and 2012, the average length of stay ranged from 74 hours in 2009 to 75.2 hours in 2010. The average length of stay in 2011 was 56.52 hours and 53.72 hours in 2012, all in the group of patients who did not remain in the ICU postoperatively. In the same period, among those in the group that needed ICU admission, the average length of stay was 138.7 hours in 2009, 90.25 hours in 2010, 79.8 hours in 2011, and 52.91 hours in 2012. During 2009 and 2010, the rate of re-hospitalization was 0%, while in 2011 and 2012, were 3.44% and 1%, respectively. according to this study, the use of femoral and sciatic nerve blocking after total knee arthroplasty allowed significant reduction in hospital stay.

  13. Relationships between Nutrient Heterogeneity, Root Growth, and Hormones: Evidence for Interspecific Variation.

    Science.gov (United States)

    Dong, Jia; Jones, Robert H; Mou, Pu

    2018-02-28

    (1) Background: Plant roots respond to nutrients through root architecture that is regulated by hormones. Strong inter-specific variation in root architecture has been well documented, but physiological mechanisms that may control the variation have not. (2) Methods: We examined correlations between root architecture and hormones to seek clues on mechanisms behind root foraging behavior. In the green house at Beijing Normal University, hydroponic culture experiments were used to examine the root responses of four species- Callistephus chinensis , Solidago canadensis , Ailanthus altissima , Oryza sativa- to two nitrogen types (NO₃ - or NH₄⁺), three nitrogen concentrations (low, medium, and high concentrations of 0.2, 1, and 18 mM, respectively) and two ways of nitrogen application (stable vs. variable). The plants were harvested after 36 days to measure root mass, 1st order root length, seminal root length for O. sativa , density of the 1st order laterals, seminal root number for O. sativa , the inter-node length of the 1st order laterals, and root hormone contents of indole-3-acetic acid, abscisic acid, and cytokinins (zeatin + zeatinriboside). (3) Results: Species differed significantly in their root architecture responses to nitrogen treatments. They also differed significantly in hormone responses to the nitrogen treatments. Additionally, the correlations between root architecture and hormone responses were quite variable across the species. Each hormone had highly species-specific relationships with root responses. (4) Conclusions: Our finding implies that a particular root foraging behavior is probably not controlled by the same biochemical pathway in all species.

  14. Relationships between Nutrient Heterogeneity, Root Growth, and Hormones: Evidence for Interspecific Variation

    Directory of Open Access Journals (Sweden)

    Jia Dong

    2018-02-01

    Full Text Available (1 Background: Plant roots respond to nutrients through root architecture that is regulated by hormones. Strong inter-specific variation in root architecture has been well documented, but physiological mechanisms that may control the variation have not. (2 Methods: We examined correlations between root architecture and hormones to seek clues on mechanisms behind root foraging behavior. In the green house at Beijing Normal University, hydroponic culture experiments were used to examine the root responses of four species—Callistephus chinensis, Solidago canadensis, Ailanthus altissima, Oryza sativa—to two nitrogen types (NO3− or NH4+, three nitrogen concentrations (low, medium, and high concentrations of 0.2, 1, and 18 mM, respectively and two ways of nitrogen application (stable vs. variable. The plants were harvested after 36 days to measure root mass, 1st order root length, seminal root length for O. sativa, density of the 1st order laterals, seminal root number for O. sativa, the inter-node length of the 1st order laterals, and root hormone contents of indole-3-acetic acid, abscisic acid, and cytokinins (zeatin + zeatinriboside. (3 Results: Species differed significantly in their root architecture responses to nitrogen treatments. They also differed significantly in hormone responses to the nitrogen treatments. Additionally, the correlations between root architecture and hormone responses were quite variable across the species. Each hormone had highly species-specific relationships with root responses. (4 Conclusions: Our finding implies that a particular root foraging behavior is probably not controlled by the same biochemical pathway in all species.

  15. Phylogenetic rooting using minimal ancestor deviation.

    Science.gov (United States)

    Tria, Fernando Domingues Kümmel; Landan, Giddy; Dagan, Tal

    2017-06-19

    Ancestor-descendent relations play a cardinal role in evolutionary theory. Those relations are determined by rooting phylogenetic trees. Existing rooting methods are hampered by evolutionary rate heterogeneity or the unavailability of auxiliary phylogenetic information. Here we present a rooting approach, the minimal ancestor deviation (MAD) method, which accommodates heterotachy by using all pairwise topological and metric information in unrooted trees. We demonstrate the performance of the method, in comparison to existing rooting methods, by the analysis of phylogenies from eukaryotes and prokaryotes. MAD correctly recovers the known root of eukaryotes and uncovers evidence for the origin of cyanobacteria in the ocean. MAD is more robust and consistent than existing methods, provides measures of the root inference quality and is applicable to any tree with branch lengths.

  16. Deciphering Phosphate Deficiency-Mediated Temporal Effects on Different Root Traits in Rice Grown in a Modified Hydroponic System

    Science.gov (United States)

    Negi, Manisha; Sanagala, Raghavendrarao; Rai, Vandna; Jain, Ajay

    2016-01-01

    Phosphate (Pi), an essential macronutrient for growth and development of plant, is often limiting in soils. Plants have evolved an array of adaptive strategies including modulation of root system architecture (RSA) for optimal acquisition of Pi. In rice, a major staple food, RSA is complex and comprises embryonically developed primary and seminal roots and post-embryonically developed adventitious and lateral roots. Earlier studies have used variant hydroponic systems for documenting the effects of Pi deficiency largely on primary root growth. Here, we report the temporal effects of Pi deficiency in rice genotype MI48 on 15 ontogenetically distinct root traits by using easy-to-assemble and economically viable modified hydroponic system. Effects of Pi deprivation became evident after 4 days- and 7 days-treatments on two and eight different root traits, respectively. The effects of Pi deprivation for 7 days were also evident on different root traits of rice genotype Nagina 22 (N22). There were genotypic differences in the responses of primary root growth along with lateral roots on it and the number and length of seminal and adventitious roots. Notably though, there were attenuating effects of Pi deficiency on the lateral roots on seminal and adventitious roots and total root length in both these genotypes. The study thus revealed both differential and comparable effects of Pi deficiency on different root traits in these genotypes. Pi deficiency also triggered reduction in Pi content and induction of several Pi starvation-responsive (PSR) genes in roots of MI48. Together, the analyses validated the fidelity of this modified hydroponic system for documenting Pi deficiency-mediated effects not only on different traits of RSA but also on physiological and molecular responses. PMID:27200025

  17. Effect of canal length and curvature on working length alteration with WaveOne reciprocating files.

    Science.gov (United States)

    Berutti, Elio; Chiandussi, Giorgio; Paolino, Davide Salvatore; Scotti, Nicola; Cantatore, Giuseppe; Castellucci, Arnaldo; Pasqualini, Damiano

    2011-12-01

    This study evaluated the working length (WL) modification after instrumentation with WaveOne Primary (Dentsply Maillefer, Ballaigues, Switzerland) reciprocating files and the incidence of overinstrumentation in relation to the initial WL. Thirty-two root canals of permanent teeth were used. The angles of curvature of the canals were calculated on digital radiographs. The initial WL with K-files was transferred to the matched WaveOne Primary reciprocating files. After glide paths were established with PathFile (Dentsply Maillefer, Ballaigues, Switzerland), canals were shaped with WaveOne Primary referring to the initial WL. The difference between the postinstrumentation canal length and the initial canal length was analyzed by using a fiberoptic inspection microscope. Data were analyzed with a balanced 2-way factorial analysis of variance (P < .05). Referring to the initial WL, 24 of 32 WaveOne Primary files projected beyond the experimental apical foramen (minimum-maximum, 0.14-0.76 mm). A significant decrease in the canal length after instrumentation (95% confidence interval ranging from -0.34 mm to -0.26 mm) was detected. The canal curvature significantly influenced the WL variation (F(1) = 30.65, P < .001). The interaction between the initial canal length and the canal curvature was statistically significant (F(2) = 4.38, P = .014). Checking the WL before preparation of the apical third of the root canal is recommended when using the new WaveOne NiTi single-file system. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  18. Decreased length of stay and earlier oral feeding associated with standardized postoperative clinical care for total gastrectomies at a cancer center.

    Science.gov (United States)

    Selby, Luke V; Rifkin, Marissa B; Yoon, Sam S; Ariyan, Charlotte E; Strong, Vivian E

    2016-09-01

    Standardization of postoperative care has been shown to decrease postoperative length of stay. In June 2009, we standardized postoperative care for all gastrectomies at our institution. Four years' worth of total gastrectomies (2 years prior to standardization and 2 years after standardization) were reviewed to determine the effect of standardization on postoperative care, length of stay, complications, and readmissions. Between June 2007 and July 2011, 99 patients underwent curative intent open total gastrectomy: 51 patients prior to standardization, and 48 patients poststandardization. Patients were predominantly male (70%); median age was 63; and median body mass index was 26. Standardization of postoperative care was associated with a decrease in median time to beginning both clear liquids and a postgastrectomy diet, earlier removal of epidural catheters, earlier use of oral pain medication, less time receiving intravenous fluids, and decreased length of stay (all P Care Center, or readmission. Institution of standardized postoperative orders for total gastrectomy was associated with a significantly decreased length of stay and earlier oral feeding without increasing postoperative complications, early postoperative outpatient visits, or readmissions. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Responses of root physiological characteristics and yield of sweet potato to humic acid urea fertilizer.

    Directory of Open Access Journals (Sweden)

    Xiaoguang Chen

    Full Text Available Humic acid (HA, not only promote the growth of crop roots, they can be combined with nitrogen (N to increase fertilizer use efficiency and yield. However, the effects of HA urea fertilizer (HA-N on root growth and yield of sweet potato has not been widely investigated. Xushu 28 was used as the experimental crop to investigate the effects of HA-N on root morphology, active oxygen metabolism and yield under field conditions. Results showed that nitrogen application alone was not beneficial for root growth and storage root formation during the early growth stage. HA-N significantly increased the dry weight of the root system, promoted differentiation from adventitious root to storage root, and increased the overall root activity, total root length, root diameter, root surface area, as well as root volume. HA-N thus increased the activity of superoxide dismutase (SOD, peroxidase (POD, and Catalase (CAT as well as increasing the soluble protein content of roots and decreasing the malondialdehyde (MDA content. HA-N significantly increased both the number of storage roots per plant increased by 14.01%, and the average fresh weight per storage root increased by 13.7%, while the yield was also obviously increased by 29.56%. In this study, HA-N increased yield through a synergistic increase of biological yield and harvest index.

  20. A study of root canal morphology of human primary incisors and molars using cone beam computerized tomography: an in vitro study.

    Science.gov (United States)

    Gaurav, Vivek; Srivastava, Nikhil; Rana, Vivek; Adlakha, Vivek Kumar

    2013-01-01

    Variations in morphology of root canals in primary teeth usually leads to complications during and after endodontic therapy. To improve the success in endodontics, a thorough knowledge of the root canal morphology is essential. The aim of this study was to assess the variation in number and morphology of the root canals of primary incisors and molars and to study the applicability of cone beam computerized tomography (CBCT) in assessing the same. A total of 60 primary molars and incisors with full root length were collected and various parameters such as the number of roots, number of canals, diameter of root canal at cementoenamel junction and middle-third, length and angulations of roots of primary molars and incisors were studied using CBCT. The observations were put to descriptive statistics to find out the frequency, mean, standard deviation and range for all four subgroups. Further, unpaired t-test was used to compare these parameters between subgroups and analysis of variance test was implemented to evaluate the parameters within the subgroups. The CBCT showed the presence of bifurcation of root canal at middle third in 13% of mandibular incisors while 20% of mandibular molars had two canals in distal root. The diameter of distobuccal root canal of maxillary molars and mesiolingual canal of mandibular molars was found to be minimum. CBCT is a relatively new and effective technology, which provides an auxiliary imaging modality to supplement conventional radiography for assessing the variation in root canal morphology of primary teeth.

  1. Root traits contributing to plant productivity under drought

    Directory of Open Access Journals (Sweden)

    Louise eComas

    2013-11-01

    Full Text Available Geneticists and breeders are positioned to breed plants with root traits that improve productivity under drought. However, a better understanding of root functional traits and how traits are related to whole plant strategies to increase crop productivity under different drought conditions is needed. Root traits associated with maintaining plant productivity under drought include small fine root diameters, long specific root length (SRL, and considerable root length density, especially at depths in soil with available water. In environments with late season water deficits, small xylem diameters in targeted seminal roots save soil water deep in the soil profile for use during crop maturation and result in improved yields. Capacity for deep root growth and large xylem diameters in deep roots may also improve root acquisition of water when ample water at depth is available. Xylem pit anatomy that makes xylem less ‘leaky’ and prone to cavitation warrants further exploration holding promise that such traits may improve plant productivity in water-limited environments without negatively impacting yield under adequate water conditions. Rapid resumption of root growth following soil rewetting may improve plant productivity under episodic drought. Genetic control of many of these traits through breeding appears feasible. Several recent reviews have covered methods for screening root traits but an appreciation for the complexity of root systems (e.g. functional differences between fine and coarse roots needs to be paired with these methods to successfully identify relevant traits for crop improvement. Screening of root traits at early stages in plant development can proxy traits at mature stages but verification is needed on a case by case basis that traits are linked to increased crop productivity under drought. Examples in lesquerella (Physaria and rice (Oryza show approaches to phenotyping of root traits and current understanding of root trait

  2. Rooting of stem cuttings of ixora

    Directory of Open Access Journals (Sweden)

    Aline De Souza Silva

    2015-08-01

    Full Text Available The ixora is ornamental plant widely used in landscaping. In order to maximize the propagation of cuts, we evaluated the concentrations of auxin (indolbutiric acid and the presence of leaves on the rooting in cuts of Ixora coccinea L. The experiment was conducted in randomized block design, in factorial design 3x4, with three types of cuts (without leaf, with two or four leaves, four concentrations of indolbutiric acid (0, 1000, 2000 and 4000 mg L-1, with four replications and 10 cuts in each experimental unit. After 53 days of implantation the experiment, evaluated the survival(%, rooting(%, sprouting(%, formation of callus(%, number, length and biomass of roots formed. The interaction of the type of cuts with concentrations of auxin was not significant for any of the variables analyzed. The survival of cuttings was not influenced by the treatments. Cuts with two or four leaves presented rooting and length of roots above the cuttings without leaves. The application of auxin does not substitute the presence of leaf in cuts of ixora in vegetative propagation. The vegetative propagation by cut of ixora can be made without application of auxin, and the leaves must be maintained in the cuttings.

  3. Inconsistency in the Crown-to-Root Ratios of Single-Rooted Premolars Measured by 2D and 3D Examinations.

    Science.gov (United States)

    Hong, Hsiang-Hsi; Liu, Heng-Liang; Hong, Adrienne; Chao, Pu

    2017-11-28

    Micro-computed tomography (micro-CT) was applied to elucidate the relationship between the three-dimensional (3D) root surface area (RSA) and two-dimensional (2D) crown-to-root ratio (CRR) of extracted teeth to classify the periodontitis and assign a periodontal/prosthetic prognosis. A total of 31 maxillary and 35 mandibular single-rooted human premolars were examined. The amount of periodontal support on the basis of 3D RSA and 2D root length (RL) at CRRs of 1:1, 5:4, 3:2, and 2:1 were analyzed. Both maxillary and mandibular premolars demonstrated a nonsignificant RSA percentage at the evaluated CRRs. The coronal 21%-22% 2D RL and the 26%-28% 3D RSA bone loss apical to the cemento-enamel junction corresponded to a CRR of 1:1, relating to mild-moderate periodontitis. The coronal 30%-31% 2D RL and the 41%-42% 3D RSA bone loss corresponded to a CRR of 5:4, correlating to severe periodontitis. More severe clinical attachment loss (CAL) was observed in the 3D RSA measurement than in the 2D RL measurement at the evaluated CRRs. The amount of CAL at the CRR of 1:1 was inadequate to assess the severity of periodontitis on the basis of the 2D RL and 3D RSA measurements.

  4. Effects of synthetic hormone substitutes and genotypes on rooting ...

    African Journals Online (AJOL)

    The vine cuttings were sampled for rooting percentage, number of roots, root length and mini tuber initiation 21 days after treatment (DAT). The number and weight of tubers obtained from IBA and wood ash treated vines were not significantly different. The rice straw ash, IBA and neem leaves powder treated vines produced ...

  5. Comparative Analysis of Crack Propagation in Roots with Hand and Rotary Instrumentation of the Root Canal -An Ex-vivo Study.

    Science.gov (United States)

    Kumari, Manju Raj; Krishnaswamy, Manjunath Mysore

    2016-07-01

    Success of any endodontic treatment depends on strict adherence to 'endodontic triad'. Preparation of root canal system is recognized as being one of the most important stages in root canal treatment. At times, we inevitably end up damaging root dentin which becomes a Gateway for infections like perforation, zipping, dentinal cracks and minute intricate fractures or even vertical root fractures, thereby resulting in failure of treatment. Several factors may be responsible for the formation of dentinal cracks like high concentration of sodium hypochlorite, compaction methods and various canal shaping methods. To compare and evaluate the effects of root canal preparation techniques and instrumentation length on the development of apical root cracks. Seventy extracted premolars with straight roots were mounted on resin blocks with simulated periodontal ligaments, exposing 1-2 mm of the apex followed by sectioning of 1mm of root tip for better visualization under stereomicroscope. The teeth were divided into seven groups of 10 teeth each - a control group and six experimental groups. Subgroup A & B were instrumented with: Stainless Steel hand files (SS) up to Root Canal Length (RCL) & (RCL -1 mm) respectively; sub group C & D were instrumented using ProTaper Universal (PTU) up to RCL and (RCL -1mm) respectively; subgroup E & F were instrumented using ProTaper Next (PTN) up to RCL & (RCL -1 mm) respectively. Stereomicroscopic images of the instrumentation sequence were compared for each tooth. The data was analyzed statistically using descriptive analysis by 'Phi' and 'Cramers' test to find out statistical significance between the groups. The level of significance was set at phand file group showed most cracks followed by ProTaper Universal & ProTaper Next though statistically not significant. Samples instrumented up to 1mm short of working length (RCL-1mm) showed lesser number of cracks. All groups showed cracks formation, the stainless steel group being the highest

  6. Reducing the length of hospital stay after total knee arthroplasty: influence of femoral and sciatic nerve block

    Directory of Open Access Journals (Sweden)

    Lúcio Honório de Carvalho Júnior

    2015-02-01

    Full Text Available Objective: the aim of this study is to evaluate the change in length of hospital stay postoperatively for Total Knee Arthroplasty after using femoral and sciatic nerve block. Materials and methods: the medical records of 287 patients were evaluated, taking into account the number of hours of admission, the percentage and the reason for re-hospitalization within 30 days, as well as associated complications. All patients were divided into two groups according or not to whether they were admitted to ICU or not. During the years 2009 and 2010, isolated spinal anesthesia was the method used in the procedure. From 2011 on, femoral and sciatic nerve blocking was introduced. Results: between the years 2009 and 2012, the average length of stay ranged from 74 hours in 2009 to 75.2 hours in 2010. The average length of stay in 2011 was 56.52 hours and 53.72 hours in 2012, all in the group of patients who did not remain in the ICU postoperatively. In the same period, among those in the group that needed ICU admission, the average length of stay was 138.7 hours in 2009, 90.25 hours in 2010, 79.8 hours in 2011, and 52.91 hours in 2012. During 2009 and 2010, the rate of re-hospitalization was 0%, while in 2011 and 2012, were 3.44% and 1%, respectively. Conclusion: according to this study, the use of femoral and sciatic nerve blocking after total knee arthroplasty allowed significant reduction in hospital stay.

  7. Heuristic Aspect of the Lateral Root Initiation Index: A Case Study of the Role of Nitric Oxide in Root Branching

    Directory of Open Access Journals (Sweden)

    Veronica Lira-Ruan

    2013-10-01

    Full Text Available Premise of the study: Lateral root (LR initiation (LRI is a central process in root branching. Based on LR and/or LR primordium densities, it has been shown that nitric oxide (NO promotes LRI. However, because NO inhibits primary root growth, we hypothesized that NO may have an opposite effect if the analysis is performed on a cellular basis. Using a previously proposed parameter, the LRI index (which measures how many LRI events take place along a root portion equivalent to the length of a single file of 100 cortical cells of average length, we addressed this hypothesis and illustrate here that the LRI index provides a researcher with a tool to uncover hidden but important information about root initiation. Methods and Results: Arabidopsis thaliana roots were treated with an NO donor (sodium nitroprusside [SNP] and/or an NO scavenger (2-(4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide [cPTIO]. LRI was analyzed separately in the root portions formed before and during the treatment. In the latter, SNP caused root growth inhibition and an increase in the LR density accompanied by a decrease in LRI index, indicating overall inhibitory outcome of the NO donor on branching. The inhibitory effect of SNP was reversed by cPTIO, showing the NO-specific action of SNP on LRI. Conclusions: Analysis of the LRI index permits the discovery of otherwise unknown modes of action of a substance on the root system formation. NO has a dual action on root branching, slightly promoting it in the root portion formed before the treatment and strongly inhibiting it in the root portion formed during the treatment.

  8. Association of nursing-documented ambulation with length of stay following total laparoscopic hysterectomy for benign gynecologic disease

    OpenAIRE

    Kim, Kidong; Yoo, Sooyoung; Yang, Eun Joo; No, Jae Hong; Hwang, Hee; Kim, Yong-Beom

    2013-01-01

    Objective The objective was to examine the association of postoperative physical activity with length of stay in patients who received total laparoscopic hysterectomy for benign gynecologic disease. Methods The case group was composed of 70 patients who entered a critical pathway for elective total laparoscopic hysterectomy from 2009 to 2012 and were discharged behind schedule. The control group was selected from patients who were discharged on schedule, and matched to cases using 1:3 ratio p...

  9. An evaluation of root resorption after orthodontic treatment.

    Science.gov (United States)

    Thomas, E; Evans, W G; Becker, P

    2012-08-01

    Root resorption is commonly seen, albeit in varying degrees, in cases that have been treated orthodontically. In this retrospective study the objective was to compare the amount of root resorption observed after active orthodontic treatment had been completed with one of three different appliance systems, namely, Tip Edge, Modified Edgewise and Damon. The sample consisted of pre and post-treatment cephalograms of sixty eight orthodontic cases. Root resorption of the maxillary central incisor was assessed from pre- and post- treatment lateral ce phalograms using two methods. In the first, overall tooth length from the incisal edge to the apex was measured on both pre and post-treatment lateral cephalograms and root resorption was recorded as an actual millimetre loss of tooth length. There was a significant upward linear trend (p = 0.052) for root resorption from the Tip Edge Group to the Damon Group. In the second method root resorption was visually evaluated by using the five grade ordinal scale of Levander and Malmgren (1988). It was found that the majorty of cases in the sample came under Grade 1 and Grade 2 category of root resorption. Statistical evaluation tested the extent of agree ment in this study between visual measurements and actual measurements and demonstrated a significant association (p = 0.018) between the methods.

  10. Determination of biological activities and total phenolic contents of flowers of jasminum humile and roots of dorema aucheri

    International Nuclear Information System (INIS)

    Khan, A.; Farooq, U.; Ullah, F.; Iqbal, J.

    2014-01-01

    The present study was designed to investigate in vitro antioxidant, NO scavenging, and antibacterial activities as well as total phenolic contents of different extracts of flowers of Jasminum humile and roots of Dorema aucheri. The plant extracts showed significant antioxidant activity, having IC50 values comparable to those of references used in each assay and also inhibited accumulation of nitrite in vitro. The plant extracts yielded phenolic contents and showed significant antibacterial activity. The observed antioxidant potential and phenolic contents of the extracts showed that flowers of J. humile and roots of D. aucheri are potential source of natural antioxidants that may help to retard oxidative degradation and microbial growth in food industry. (author)

  11. Radiographic technical quality of root canal treatment performed ex vivo by dental students at Valencia University Medical and Dental School, Spain

    Science.gov (United States)

    Faus-Matoses, Vicente; Alegre-Domingo, Teresa; Faus-Llácer, Vicente J.

    2014-01-01

    Objectives: To evaluate radiographically the quality of root canal fillings and compare manual and rotary preparation performed on extracted teeth by undergraduate dental students. Study Design: A total of 561 premolars and molars extracted teeth were prepared using nickel-titanium rotary files or manual instrumentation and filled with gutta-percha using a cold lateral condensation technique, by 4th grade undergraduate students. Periapical radiographs were used to assess the technical quality of the root canal filling, evaluating three variables: length, density and taper. These data were recorded, scored and used to study the “technical success rate” and the “overall score”. The length of each root canal filling was classified as acceptable, short and overfilled, based on their relationship with the radiographic apex. Density and taper of filling were evaluated based on the presence of voids and the uniform tapering of the filling, respectively. Statistical analysis was used to evaluate the quality of root canal treatment, considering p rotary instruments (52% against 28% with a manual one, p rotary instrumentation. Key words:Dental education, endodontics, rotary instrumentation, radiographs, root canal treatment, undergraduate students. PMID:24121911

  12. GAMMA IRRADIATION OF SUGAR BEET SEEDS INDUCED PLANT RESISTANCE TO ROOT-KNOT NEMATODE MELOIDOGYNE INCOGNITA

    International Nuclear Information System (INIS)

    ABD EL FATTAH, A.I.; KAMEL, H.A.; EL-NAGDI, W.M.A.

    2008-01-01

    The main objective of this study was to investigate the effect of irradiation of sugar beet seeds on the plant resistance to root-knot nematode Meloidogyne incognita infection in addition to some morphological parameters, biochemical components and root technological characters. Relative to control (non-irradiated seeds), the obtained data showed that, all doses except 10 Gy significantly increased root length of un inoculated plants and the most effective dose was 200 Gy. All doses significantly decreased root diameter except 50 and 100 Gy. The 10 and 400 Gy significantly reduced root fresh weight while 50, 100 and 200 Gy caused non-significant increase. All doses significantly increased root fresh weight/dry weight than control. There was non-significant effect on the morphological parameters of the plants germinated from gamma irradiated seeds and inoculated with Meloidogyne incognita. Total chlorophyll of seed irradiated and un inoculated plants were significantly reduced by all doses except 200 Gy. All doses of gamma radiation caused non-significant decrease in the total chlorophyll of the infected plants. In un inoculated plants, a significant reduction in the total phenol was occurred due to all doses of gamma radiation. In contrast, in inoculated plants, 10 and 25 Gy caused significant reduction in the total phenol while 50 and 400 Gy caused significant increase in the total phenol.Significant increase in sucrose % was observed due to 10 Gy in the un inoculated plants. The 400 Gy caused significant decrease while other doses caused non-significant decrease in the sucrose %. In the inoculated plants, 50, 100 and 400 Gy caused significant increase in sucrose %. All doses significantly increased total soluble salts percent (TSS %) of either inoculated or un inoculated plants. Purity % was increased by all doses in the inoculated plants.The number of galls and egg masses were reduced gradually by increasing gamma doses and 100 Gy caused the highest reduction 89

  13. Rooting and acclimatization of micropropagated marubakaido apple rootstock using Adesmia latifolia rhizobia.

    Science.gov (United States)

    Muniz, Aleksander Westphal; de Sá, Enilson Luiz; Dalagnol, Gilberto Luíz; Filho, João Américo

    2013-01-01

    In vitro rooting and the acclimatization of micropropagated rootstocks of apple trees is essential for plant development in the field. The aim of this work was to assess the use of rhizobia of Adesmia latifolia to promote rooting and acclimatization in micropropagated Marubakaido apple rootstock. An experiment involving in vitro rooting and acclimatization was performed with four strains of rhizobium and two controls, one with and the other without the addition of synthetic indoleacetic acid. The inoculated treatments involved the use of sterile inoculum and inoculum containing live rhizobia. The most significant effects on the rooting rate, primary-root length, number of roots, root length, fresh-shoot biomass, and fresh-root biomass were obtained by inoculation with strain EEL16010B and with synthetic indole acetic acid. However, there was no difference in the growth of apple explants in the acclimatization experiments. Strain EEL16010B can be used to induce in vitro rooting of the Marubakaido rootstock and can replace the use of synthetic indoleacetic acid in the rooting of this cultivar.

  14. A dual porosity model of nutrient uptake by root hairs

    KAUST Repository

    Zygalakis, K. C.; Kirk, G. J. D.; Jones, D. L.; Wissuwa, M.; Roose, T.

    2011-01-01

    Summary: • The importance of root hairs in the uptake of sparingly soluble nutrients is understood qualitatively, but not quantitatively, and this limits efforts to breed plants tolerant of nutrient-deficient soils. • Here, we develop a mathematical model of nutrient uptake by root hairs allowing for hair geometry and the details of nutrient transport through soil, including diffusion within and between soil particles. We give illustrative results for phosphate uptake. • Compared with conventional 'single porosity' models, this 'dual porosity' model predicts greater root uptake because more nutrient is available by slow release from within soil particles. Also the effect of soil moisture is less important with the dual porosity model because the effective volume available for diffusion in the soil is larger, and the predicted effects of hair length and density are different. • Consistent with experimental observations, with the dual porosity model, increases in hair length give greater increases in uptake than increases in hair density per unit main root length. The effect of hair density is less in dry soil because the minimum concentration in solution for net influx is reached more rapidly. The effect of hair length is much less sensitive to soil moisture. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

  15. A dual porosity model of nutrient uptake by root hairs

    KAUST Repository

    Zygalakis, K. C.

    2011-08-09

    Summary: • The importance of root hairs in the uptake of sparingly soluble nutrients is understood qualitatively, but not quantitatively, and this limits efforts to breed plants tolerant of nutrient-deficient soils. • Here, we develop a mathematical model of nutrient uptake by root hairs allowing for hair geometry and the details of nutrient transport through soil, including diffusion within and between soil particles. We give illustrative results for phosphate uptake. • Compared with conventional \\'single porosity\\' models, this \\'dual porosity\\' model predicts greater root uptake because more nutrient is available by slow release from within soil particles. Also the effect of soil moisture is less important with the dual porosity model because the effective volume available for diffusion in the soil is larger, and the predicted effects of hair length and density are different. • Consistent with experimental observations, with the dual porosity model, increases in hair length give greater increases in uptake than increases in hair density per unit main root length. The effect of hair density is less in dry soil because the minimum concentration in solution for net influx is reached more rapidly. The effect of hair length is much less sensitive to soil moisture. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

  16. A study of root canal morphology of human primary incisors and molars using cone beam computerized tomography: An in vitro study

    Directory of Open Access Journals (Sweden)

    Vivek Gaurav

    2013-01-01

    Full Text Available Background: Variations in morphology of root canals in primary teeth usually leads to complications during and after endodontic therapy. To improve the success in endodontics, a thorough knowledge of the root canal morphology is essential. Aim: The aim of this study was to assess the variation in number and morphology of the root canals of primary incisors and molars and to study the applicability of cone beam computerized tomography (CBCT in assessing the same. Settings and Design: A total of 60 primary molars and incisors with full root length were collected and various parameters such as the number of roots, number of canals, diameter of root canal at cementoenamel junction and middle-third, length and angulations of roots of primary molars and incisors were studied using CBCT. Statistical analysis used: The observations were put to descriptive statistics to find out the frequency, mean, standard deviation and range for all four subgroups. Further, unpaired t-test was used to compare these parameters between subgroups and analysis of variance test was implemented to evaluate the parameters within the subgroups. Results and Conclusion: The CBCT showed the presence of bifurcation of root canal at middle third in 13% of mandibular incisors while 20% of mandibular molars had two canals in distal root. The diameter of distobuccal root canal of maxillary molars and mesiolingual canal of mandibular molars was found to be minimum. CBCT is a relatively new and effective technology, which provides an auxiliary imaging modality to supplement conventional radiography for assessing the variation in root canal morphology of primary teeth.

  17. Asymmetry in development (mineralisation of permanent mandibular canine roots

    Directory of Open Access Journals (Sweden)

    Burić Mirjana V.

    2012-01-01

    Full Text Available Introduction. The development of the teeth is closely associated with the proper and unobstructed physical and psychological development of the child. Aim. To determine the existence of asymmetry in the development of the roots of the lower permanent canine teeth in different age groups of children of both sexes. Material and methods. The study was conducted on 523 ortopantomograms (253 boys and 270 girls of orthodontic patients aged 6 to 14 years of the Dental Clinic in Niš. We analyzed the development of asymmetry in the lower permanent canine root, using the method of Gleiser and Hunt, or the modification by Tijanić (1981. Results. It was found that asymmetry in the development of the root in both sexes of the lower canine teeth was present in 20 patients (3.82%, 10 boys (3.95% and 10 girls (3.70%. The difference is in the range of one stage. Asymmetric development of the roots of the lower incisors in girls and boys usually present in the 7th and 8th stages (60% in girls and in 50% in boys. In 90% of girls in developing asymmetry the root of the lower canine is present in a single stage, and in 10% of girls it presents within three stages. Asymmetric development of the root of the lower canine is the most common in the 7th and 8th stages of development (55%. Conclusion. Asymmetric root development of permanent lower canines was found in 3.82% of patients. More than half of respondents (55% had asymmetrical canine root development stage in half and three quarters of the total root length. The results of this study indicate that the canine is the tooth with very little variations in its development.

  18. Radiographic evaluation of apical root resorption following fixed orthodontic treatment

    Directory of Open Access Journals (Sweden)

    Sina Haghanifar

    2012-01-01

    Full Text Available Background and Aims: Apical root resorption is an adverse side effect of fixed orthodontic treatment which cannot be repaired. The aim of this study was to use panoramic radiographs to compare the root resorption before and after the orthodontic treatment with standard edgewise .018 appliance.Materials and Methods: The before and after treatment panoramic views of sixty-three patients needed fixed orthodontic treatment included 1520 teeth were categorized into 3 Grades (G0: without resorption, G1: mild resorption with blunt roots or ≤ 1/4 of root length, G2: moderate to severe resorption or > 1/4 to 1/2 of root length. Relationship between root resorption and sex and treatment duration was analyzed with Mann-whitney and Spearman's correlation coefficient, respectively.Results: The findings showed that 345 teeth were categorized as Grade 1. Grade 2 of root resorption was not found in this study. The highest amount of root resorption was recorded for the mandibular lateral incisor. In both gender, the root resorption of the mandible was more than that of the maxilla. The males showed significantly higher rate of resorption than the females (P0.05.Conclusion: The mandible and male patients showed higher amount of root resorption. In addition, root resorption was not related to the treatment duration and the side of the jaws.

  19. Study of optical non-linear properties of a constant total effective length multiple quantum wells system

    International Nuclear Information System (INIS)

    Solaimani, M.; Morteza, Izadifard; Arabshahi, H.; Reza, Sarkardehi Mohammad

    2013-01-01

    In this work, we have studied the effect of the number of the wells, in a multiple quantum wells structure with constant total effective length, on the optical properties of multiple quantum wells like the absorption coefficient and the refractive index by means of compact density matrix approach. GaAs/Al x Ga (1−x) As multiple quantum wells systems was selected as an example. Besides, the effect of varying number of wells on the subband energies, wave functions, number of bound states, and the Fermi energy have been also investigated. Our calculation revealed that the number of wells in a multiple quantum well is a criterion with which we can control the amount of nonlinearity. This study showed that for the third order refractive index change there is two regimes of variations and the critical well number was six. In our calculations, we have used the same wells and barrier thicknesses to construct the multiple quantum wells system. - Highlights: ► OptiOptical Non-Linear. ► Total Effective Length. ► Multiple Quantum Wells System - genetic algorithm ► Schrödinger equation solution. ► Nanostructure.

  20. Total fine root mass and nutrient content in forest ecosystems (Pinus patula Schltdl and Cham Cupressus lusitanica Mill and Quercus humboldtii bonpl.) from Piedras Blancas, Antioquia - Colombia

    International Nuclear Information System (INIS)

    Barreto Sanchez, Luis Hernan; Leon Pelaez, Juan Diego

    2005-01-01

    In the Piedras Blancas region, Antioquia - Colombia, a sampling of fine roots K > Mg > Fe > P this study sought to highlight the importance of fine roots and their concentrations of nutrients in natural forests and plantations and their relationship with nutrient cycling. For this purpose, the methodological approach comprised total root mass, both dead and alive

  1. Fine root dynamics in lodgepole pine and white spruce stands along productivity gradients in reclaimed oil sands sites.

    Science.gov (United States)

    Jamro, Ghulam Murtaza; Chang, Scott X; Naeth, M Anne; Duan, Min; House, Jason

    2015-10-01

    Open-pit mining activities in the oil sands region of Alberta, Canada, create disturbed lands that, by law, must be reclaimed to a land capability equivalent to that existed before the disturbance. Re-establishment of forest cover will be affected by the production and turnover rate of fine roots. However, the relationship between fine root dynamics and tree growth has not been studied in reclaimed oil sands sites. Fine root properties (root length density, mean surface area, total root biomass, and rates of root production, turnover, and decomposition) were assessed from May to October 2011 and 2012 using sequential coring and ingrowth core methods in lodgepole pine (Pinus contorta Dougl.) and white spruce (Picea glauca (Moench.) Voss) stands. The pine and spruce stands were planted on peat mineral soil mix placed over tailings sand and overburden substrates, respectively, in reclaimed oil sands sites in Alberta. We selected stands that form a productivity gradient (low, medium, and high productivities) of each tree species based on differences in tree height and diameter at breast height (DBH) increments. In lodgepole pine stands, fine root length density and fine root production, and turnover rates were in the order of high > medium > low productivity sites and were positively correlated with tree height and DBH and negatively correlated with soil salinity (P < 0.05). In white spruce stands, fine root surface area was the only parameter that increased along the productivity gradient and was negatively correlated with soil compaction. In conclusion, fine root dynamics along the stand productivity gradients were closely linked to stand productivity and were affected by limiting soil properties related to the specific substrate used for reconstructing the reclaimed soil. Understanding the impact of soil properties on fine root dynamics and overall stand productivity will help improve land reclamation outcomes.

  2. Halogenated auxins affect microtubules and root elongation in Lactuca sativa

    Science.gov (United States)

    Zhang, N.; Hasenstein, K. H.

    2000-01-01

    We studied the effect of 4,4,4-trifluoro-3-(indole-3-)butyric acid (TFIBA), a recently described root growth stimulator, and 5,6-dichloro-indole-3-acetic acid (DCIAA) on growth and microtubule (MT) organization in roots of Lactuca sativa L. DCIAA and indole-3-butyric acid (IBA) inhibited root elongation and depolymerized MTs in the cortex of the elongation zone, inhibited the elongation of stele cells, and promoted xylem maturation. Both auxins caused the plane of cell division to shift from anticlinal to periclinal. In contrast, TFIBA (100 micromolar) promoted elongation of primary roots by 40% and stimulated the elongation of lateral roots, even in the presence of IBA, the microtubular inhibitors oryzalin and taxol, or the auxin transport inhibitor naphthylphthalamic acid. However, TFIBA inhibited the formation of lateral root primordia. Immunostaining showed that TFIBA stabilized MTs orientation perpendicular to the root axis, doubled the cortical cell length, but delayed xylem maturation. The data indicate that the auxin-induced inhibition of elongation and swelling of roots results from reoriented phragmoplasts, the destabilization of MTs in elongating cells, and promotion of vessel formation. In contrast, TFIBA induced promotion of root elongation by enhancing cell length, prolonging transverse MT orientation, delaying cell and xylem maturation.

  3. Effect of reciprocating systems and working lengths on apical microcrack development: a micro-CT Study

    International Nuclear Information System (INIS)

    Oliveira, Bruna Paloma de; Câmara, Andréa Cruz; Duarte, Daniel Amancio; Antonino, Antonio Celso Dantas; Aguiar, Carlos Menezes; Heck, Richard John

    2017-01-01

    The objective of this study was to evaluate the effect of root canal preparation with single-file reciprocating systems at different working lengths on the development of apical microcracks using micro-computed tomographic (micro-CT) imaging. Forty extracted human mandibular incisors were randomly assigned to 4 groups (n=10) according to the systems and working length used to prepare the root canals: Group A - WaveOne Gold at apical foramen (AF), Group B - WaveOne Gold 1 mm short of the AF (AF-1 mm), Group C - Unicone (AF) and Group D - Unicone (AF-1 mm). Micro-CT scanning was performed before and after root canal preparation at an isotropic resolution of 14 μm. Then, three examiners assessed the cross-sectional images generated to detect microcracks in the apical portion of the roots. Apical microcracks were visualized in 3, 1, 1, and 3 specimens in groups A, B, C, and D, respectively. All these microcracks observed after root canal preparation already existed prior to instrumentation, and no new apical microcrack was detected. For all groups, the number of slices presenting microcracks after root canal preparation was the same as before canal preparation. Root canal preparation with WaveOne Gold and Unicone, regardless of the working length, was not associated with apical microcrack formation. (author)

  4. Effect of reciprocating systems and working lengths on apical microcrack development: a micro-CT Study

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Bruna Paloma de; Câmara, Andréa Cruz; Duarte, Daniel Amancio; Antonino, Antonio Celso Dantas; Aguiar, Carlos Menezes, E-mail: bruna_paloma@msn.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Heck, Richard John [Department of Land Resource Science, University of Guelph (Canada)

    2017-11-15

    The objective of this study was to evaluate the effect of root canal preparation with single-file reciprocating systems at different working lengths on the development of apical microcracks using micro-computed tomographic (micro-CT) imaging. Forty extracted human mandibular incisors were randomly assigned to 4 groups (n=10) according to the systems and working length used to prepare the root canals: Group A - WaveOne Gold at apical foramen (AF), Group B - WaveOne Gold 1 mm short of the AF (AF-1 mm), Group C - Unicone (AF) and Group D - Unicone (AF-1 mm). Micro-CT scanning was performed before and after root canal preparation at an isotropic resolution of 14 μm. Then, three examiners assessed the cross-sectional images generated to detect microcracks in the apical portion of the roots. Apical microcracks were visualized in 3, 1, 1, and 3 specimens in groups A, B, C, and D, respectively. All these microcracks observed after root canal preparation already existed prior to instrumentation, and no new apical microcrack was detected. For all groups, the number of slices presenting microcracks after root canal preparation was the same as before canal preparation. Root canal preparation with WaveOne Gold and Unicone, regardless of the working length, was not associated with apical microcrack formation. (author)

  5. Factors affecting root curvature of mandibular first molar

    International Nuclear Information System (INIS)

    Choi, Hang Moon; Yi, Won Jin; Heo, Min Suk; Kim, Jung Hwa; Choi, Soon Chul; Park, Tae Won

    2006-01-01

    To find the cause of root curvature by use of panoramic and lateral cephalometric radiograph. Twenty six 1st graders whose mandibular 1st molars just emerged into the mouth were selected. Panoramic and lateral cephalometric radiograph were taken at grade 1 and 6, longitudinally. In cephalometric radio graph, mandibular plane angle, ramus-occlusal place angle, gonial angle, and gonion-gnathion distance(Go-Gn distance) were measured. In panoramic radiograph, elongated root length and root angle were measured by means of digital subtraction radiography. Occlusal plane-tooth axis angle was measured, too. Pearson correlations were used to evaluate the relationships between root curvature and elongated length and longitudinal variations of all variables. Multiple regression equation using related variables was computed. The pearson correlation coefficient between curved angle and longitudinal variations of occlusal plane-tooth axis angle and ramus-occlusal plane angle was 0.350 and 0.401, respectively (p 1 +0.745X 2 (Y: root angle, X 1 : variation of occlusal plane-tooth axis angle, X 2 : variation of ramus-occlusal plane angle). It was suspected that the reasons of root curvature were change of tooth axis caused by contact with 2nd deciduous tooth and amount of mesial and superior movement related to change of occlusal plane

  6. In vitro ROOTING OF TENERA HYBRID OIL PALM (Elaeis guineensis Jacq. PLANTS1

    Directory of Open Access Journals (Sweden)

    Marlúcia Souza Souza Pádua

    2018-04-01

    Full Text Available ABSTRACT Oil palm is a woody monocot of economic importance due to high oil production from its fruits. Currently, the conventional method most used to propagate oil palm is seed germination, but success is limited by long time requirements and low germination percentage. An alternative for large-scale propagation of oil palm is the biotechnological technique of somatic embryogenesis. The rooting of plants germinated from somatic embryos is a difficult step, yet it is of great importance for later acclimatization and success in propagation. The aim of this study was to evaluate the effect of the auxins indole acetic acid (IAA and indole butyric acid (IBA on the rooting of somatic embryos of Tenera hybrid oil palm. Plants obtained by somatic embryogenesis were inoculated in modified MS medium with 10% sucrose and 0.6% agar and supplemented with IAA or IBA at concentrations of 5 µM, 10 µM, and 15 µM, and the absence of growth regulators. After 120 days, the presence of roots, root type, length of the longest root, number of roots, number of leaves, and shoot length were analyzed. Growth regulators were favorable to rooting; plants cultivated with IBA growth regulator at 15 µM showed higher rooting percentage (87% and better results for the parameters of number of roots (1.33 and shoot length (9.83.

  7. Linking root traits and competitive success in grassland species

    NARCIS (Netherlands)

    Ravenek, Janneke M.; Mommer, Liesje; Visser, Eric J.W.; Ruijven, van Jasper; Paauw, van der Jan Willem; Smit-Tiekstra, Annemiek; Caluwe, de Hannie; Kroon, de Hans

    2016-01-01

    Background and aims: Competition is an important force shaping plant communities. Here we test the hypothesis that high overall root length density and selective root placement in nutrient patches, as two alternative strategies, confer competitive advantage in species mixtures. Methods: We

  8. Effect of piezocision on root resorption associated with orthodontic force: A microcomputed tomography study.

    Science.gov (United States)

    Patterson, Braydon M; Dalci, Oyku; Papadopoulou, Alexandra K; Madukuri, Suman; Mahon, Jonathan; Petocz, Peter; Spahr, Axel; Darendeliler, M Ali

    2017-01-01

    The purpose of this study was to investigate the effect of piezocision on orthodontically induced inflammatory root resorption. Fourteen patients were included in this split-mouth study; 1 side was assigned to piezocision, and the other side served as the control. Vertical corticotomy cuts of 4 to 5 mm in length were performed on either side of each piezocision premolar, and 150-g buccal tipping forces were applied to the premolars. After 4 weeks, the maxillary first premolars were extracted and scanned with microcomputed tomography. There was a significantly greater total amount of root resorption seen on the piezocision sides when compared with the control sides (P = 0.029). The piezocision procedure resulted in a 44% average increase in root resorption. In 5 patients, there was noticeable piezocision-related iatrogenic root damage. When that was combined with the orthodontic root resorption found on the piezocision-treated teeth, there was a statistically significant 110% average increase in volumetric root loss when compared with the control side (P = 0.005). The piezocision procedure that initiates the regional acceleratory phenomenon may increase the iatrogenic root resorption when used in conjunction with orthodontic forces. Piezocision applied close to the roots may cause iatrogenic damage to the neighboring roots and should be used carefully. Copyright © 2017.

  9. 1-Aminocyclopropane-1-carboxylic acid (ACC) concentration and ACC synthase expression in soybean roots, root tips, and soybean cyst nematode (Heterodera glycines)-infected roots.

    Science.gov (United States)

    Tucker, Mark L; Xue, Ping; Yang, Ronghui

    2010-01-01

    Colonization of plant roots by root knot and cyst nematodes requires a functional ethylene response pathway. However, ethylene plays many roles in root development and whether its role in nematode colonization is direct or indirect, for example lateral root initiation or root hair growth, is not known. The temporal requirement for ethylene and localized synthesis of ethylene during the life span of soybean cyst nematode (SCN) on soybean roots was further investigated. Although a significant increase in ethylene evolution was not detected from SCN-colonized roots, the concentration of the immediate precursor to ethylene, 1-aminocyclopropane-1-carboxylic acid (ACC), was higher in SCN-colonized root pieces and root tips than in other parts of the root. Moreover, expression analysis of 17 ACC synthase (ACS) genes indicated that a select set of ACS genes is expressed in SCN-colonized root pieces that is clearly different from the set of genes expressed in non-colonized roots or root tips. Semi-quantitative real-time PCR indicated that ACS transcript accumulation correlates with the high concentration of ACC in root tips. In addition, an ACS-like sequence was found in the public SCN nucleotide database. Acquisition of a full-length sequence for this mRNA (accession GQ389647) and alignment with transcripts for other well-characterized ACS proteins indicated that the nematode sequence is missing a key element required for ACS activity and therefore probably is not a functional ACS. Moreover, no significant amount of ACC was found in any growth stage of SCN that was tested.

  10. Root proliferation in native perennial grasses of arid Patagonia, Argentina

    Institute of Scientific and Technical Information of China (English)

    Yanina A. TORRES; Mara M. MUJICA; Sandra S. BAIONI; Jos ENTO; Mara N. FIORETTI; Guillermo TUCAT; Carlos A. BUSSO; Oscar A. MONTENEGRO; Leticia ITHURRART; Hugo D. GIORGETTI; Gustavo RODRGUEZ; Diego BENTIVEGNA; Roberto E. BREVEDAN; Osvaldo A. FERNNDEZ

    2014-01-01

    Pappophorum vaginatum is the most abundant C4 perennial grass desirable to livestock in rangelands of northeastern Patagonia, Argentina. We hypothesized that (1) defoliation reduce net primary productivity, and root length density and weight in the native species, and (2) root net primary productivity, and root length density and weight, are greater in P. vaginatum than in the other, less desirable, native species (i.e., Aristida spegazzinii, A. subulata and Sporobolus cryptandrus). Plants of all species were either exposed or not to a severe defoliation twice a year during two growing seasons. Root proliferation was measured using the cylinder method. Cylindrical, iron structures, wrapped up using nylon mesh, were buried diagonally from the periphery to the center on individual plants. These structures, initially filled with soil without any organic residue, were dug up from the soil on 25 April 2008, after two successive defoliations in mid-spring 2007. During the second growing season (2008-2009), cylinders were destructively harvested on 4 April 2009, after one or two defoliations in mid-and/or late-spring, respectively. Roots grown into the cylinders were obtained after washing the soil manually. Defoliation during two successive years did reduce the study variables only after plants of all species were defoliated twice, which supported the first hypothesis. The greater root net primary productivity, root length den-sity and weight in P. vaginatum than in the other native species, in support of the second hypothesis, could help to explain its greater abundance in rangelands of Argentina.

  11. Endophytic Bacteria Isolated from Panax ginseng Improves Ginsenoside Accumulation in Adventitious Ginseng Root Culture

    Directory of Open Access Journals (Sweden)

    Xiaolin Song

    2017-05-01

    Full Text Available Ginsenoside is the most important secondary metabolite of ginseng. Natural sources of wild ginseng have been overexploited. Although root culture could reduce the length of the growth cycle of ginseng, the number of ginsenosides is fewer and their contents are lower in adventitious roots of ginseng than that in ginseng cultivated in the field. In this study, we investigated the effects of endophytic bacterial elicitors on biomass and ginsenoside production in adventitious roots cultures of Panax ginseng. Endophyte LB 5-3 as an elicitor could increase biomass and ginsenoside accumulation in ginseng adventitious root culture. After 6 days elicitation with a 10.0 mL of strain LB 5-3, the content of total ginsenoside was 2.026 mg g−1 which was four times more than that in unchallenged roots. The combination of methyl jasmonate and strain LB 5-3 had a negative effect on ginseng adventitious root growth and ginsenoside production. The genomic DNA of strain LB 5-3 was sequenced, and was found to be most closely related to Bacillus altitudinis (KX230132.1. The challenged ginseng adventitious root extracts exerted inhibitory effect against the HepG2 cells, which IC50 value was 0.94 mg mL−1.

  12. De Novo Characterization of the Mung Bean Transcriptome and Transcriptomic Analysis of Adventitious Rooting in Seedlings Using RNA-Seq.

    Science.gov (United States)

    Li, Shi-Weng; Shi, Rui-Fang; Leng, Yan

    2015-01-01

    Adventitious rooting is the most important mechanism underlying vegetative propagation and an important strategy for plant propagation under environmental stress. The present study was conducted to obtain transcriptomic data and examine gene expression using RNA-Seq and bioinformatics analysis, thereby providing a foundation for understanding the molecular mechanisms controlling adventitious rooting. Three cDNA libraries constructed from mRNA samples from mung bean hypocotyls during adventitious rooting were sequenced. These three samples generated a total of 73 million, 60 million, and 59 million 100-bp reads, respectively. These reads were assembled into 78,697 unigenes with an average length of 832 bp, totaling 65 Mb. The unigenes were aligned against six public protein databases, and 29,029 unigenes (36.77%) were annotated using BLASTx. Among them, 28,225 (35.75%) and 28,119 (35.62%) unigenes had homologs in the TrEMBL and NCBI non-redundant (Nr) databases, respectively. Of these unigenes, 21,140 were assigned to gene ontology classes, and a total of 11,990 unigenes were classified into 25 KOG functional categories. A total of 7,357 unigenes were annotated to 4,524 KOs, and 4,651 unigenes were mapped onto 342 KEGG pathways using BLAST comparison against the KEGG database. A total of 11,717 unigenes were differentially expressed (fold change>2) during the root induction stage, with 8,772 unigenes down-regulated and 2,945 unigenes up-regulated. A total of 12,737 unigenes were differentially expressed during the root initiation stage, with 9,303 unigenes down-regulated and 3,434 unigenes up-regulated. A total of 5,334 unigenes were differentially expressed between the root induction and initiation stage, with 2,167 unigenes down-regulated and 3,167 unigenes up-regulated. qRT-PCR validation of the 39 genes with known functions indicated a strong correlation (92.3%) with the RNA-Seq data. The GO enrichment, pathway mapping, and gene expression profiles reveal

  13. De Novo Characterization of the Mung Bean Transcriptome and Transcriptomic Analysis of Adventitious Rooting in Seedlings Using RNA-Seq.

    Directory of Open Access Journals (Sweden)

    Shi-Weng Li

    Full Text Available Adventitious rooting is the most important mechanism underlying vegetative propagation and an important strategy for plant propagation under environmental stress. The present study was conducted to obtain transcriptomic data and examine gene expression using RNA-Seq and bioinformatics analysis, thereby providing a foundation for understanding the molecular mechanisms controlling adventitious rooting. Three cDNA libraries constructed from mRNA samples from mung bean hypocotyls during adventitious rooting were sequenced. These three samples generated a total of 73 million, 60 million, and 59 million 100-bp reads, respectively. These reads were assembled into 78,697 unigenes with an average length of 832 bp, totaling 65 Mb. The unigenes were aligned against six public protein databases, and 29,029 unigenes (36.77% were annotated using BLASTx. Among them, 28,225 (35.75% and 28,119 (35.62% unigenes had homologs in the TrEMBL and NCBI non-redundant (Nr databases, respectively. Of these unigenes, 21,140 were assigned to gene ontology classes, and a total of 11,990 unigenes were classified into 25 KOG functional categories. A total of 7,357 unigenes were annotated to 4,524 KOs, and 4,651 unigenes were mapped onto 342 KEGG pathways using BLAST comparison against the KEGG database. A total of 11,717 unigenes were differentially expressed (fold change>2 during the root induction stage, with 8,772 unigenes down-regulated and 2,945 unigenes up-regulated. A total of 12,737 unigenes were differentially expressed during the root initiation stage, with 9,303 unigenes down-regulated and 3,434 unigenes up-regulated. A total of 5,334 unigenes were differentially expressed between the root induction and initiation stage, with 2,167 unigenes down-regulated and 3,167 unigenes up-regulated. qRT-PCR validation of the 39 genes with known functions indicated a strong correlation (92.3% with the RNA-Seq data. The GO enrichment, pathway mapping, and gene expression profiles

  14. Chrysanthemum cutting productivity and rooting ability are improved by grafting.

    Science.gov (United States)

    Zhang, Jing; Chen, Sumei; Liu, Ruixia; Jiang, Jiafu; Chen, Fadi; Fang, Weimin

    2013-01-01

    Chrysanthemum has been commercially propagated by rooting of cuttings, whereas the quality will decline over multiple collections from a single plant. Therefore, we compared the vigour, rooting ability, and some physiological parameters between cuttings harvested from nongrafted "Jinba" (non-grafted cuttings) with those collected from grafted "Jinba" plants onto Artemisia scoparia as a rootstock (grafted cuttings). The yield, length, node number, stem diameter, fresh weight, and dry weight of the grafted cuttings were superior to the non-grafted cuttings. Also grafted cuttings "Jinba" rooted 1 day earlier, but showing enhanced rooting quality including number, length, diameter, and dry weight of roots, where compared to the non-grafted. The physiological parameters that indicated contents of soluble protein, peroxidase activity, soluble sugar, and starch, ratios of soluble sugar/nitrogen ratio, and carbohydrate/nitrogen (C/N), as well as contents of indole-3-acetic acid (IAA) and abscisic acid (ABA), and IAA/ABA ratio were significantly increased in the grafted cuttings. This suggested their important parts in mediating rooting ability. Results from this study showed that grafting improved productivity and rooting ability related to an altered physiology, which provide a means to meet the increasing demand.

  15. Growth and root development of four mangrove seedlings under varying salinity

    Science.gov (United States)

    Basyuni, M.; Keliat, D. A.; Lubis, M. U.; Manalu, N. B.; Syuhada, A.; Wati, R.; Yunasfi

    2018-03-01

    This present study describes four mangrove seedlings namely Bruguiera cylindrica, B. sexangula, Ceriops tagal, and Rhizophora apiculata in response to salinity with particular emphasis to root development. The seedlings of four mangroves were grown for 5 months in 0%, 0.5%, 1.5%, 2.0% and 3.0% salt concentration. Salinity significantly decreased the growth (diameter and plant height) of all mangrove seedlings. Root developments were observed from the tap and lateral root. The number, length and diameter of both roots-typed of B. cylindrica, B. sexangula and C. tagal seedlings significantly decreased with increasing salt concentration with optimum development at 0.5% salinity. By contrast, the number, length, and diameter of tap root of R. apiculata seedlings were significantly enhanced by salt with maximal stimulation at 0.5%, and this increase was attenuated by increasing salinity. On the other hand, lateral root development of R. apiculata significantly thrived up to 1.5% salinity then decreasing with the increasing salinity. The different response of root development suggested valuable information for mangrove rehabilitation in North Sumatra and their adaption to withstand salt stress.

  16. Fine roots in stands of Fagus sylvatica and Picea abies along a gradient of soil acidification

    International Nuclear Information System (INIS)

    Braun, Sabine; Cantaluppi, Leonardo; Flueckiger, Walter

    2005-01-01

    Root length of naturally grown young beech trees (Fagus sylvatica L.) was investigated in 26 forest plots of differing base saturation and nitrogen deposition. The relative length of finest roots (<0.25 mm) was found to decrease in soils with low base saturation. A similar reduction of finest roots in plots with high nitrogen deposition was masked by the effect of base saturation. The formation of adventitious roots was enhanced in acidic soils. The analysis of 128 soil profiles for fine roots of all species present in stands of either Fagus sylvatica L., Picea abies [Karst.] L. or both showed a decreased rooting depth in soils with ≤20% base saturation and in hydromorphic soils. For base rich, well drained soils an average rooting depth of 108 cm was found. This decreased by 28 cm on acidic, well drained soils. The results suggest an effect of the current soil acidification in Switzerland and possibly also of nitrogen deposition on the fine root systems of forest trees. - Fine root length of Fagus sylvatica and fine root depth in stands of Fagus sylvatica and/or Picea abies were impaired in soils with low base saturation

  17. Influences of image resolution on herbaceous root morphological parameters

    Directory of Open Access Journals (Sweden)

    ZHANG Zeyou

    2014-06-01

    Full Text Available Root images of four herbaceous species (including Plantago virginica,Solidago canadensis,Conyza canadensis and Erigeron philadelphicus were obtained by using EPSON V7000 scanner with different resolutions.Root morphological parameters including root length,diameter,volume and area were determined by using a WinRhizo root analyzing software.The results show a distinct influence of image resolution on root morphological parameter.For different herbaceous species,the optimal resolutions of root images,which would produce an acceptable precision with relative short time,vary with different species.For example,a resolution of 200 dpi was recommended for the root images of Plantago virginica and S.Canadensis, while 400 dpi for Conyza canadensis and Erigeron philadelphicus.

  18. Variations in the Root Form and Root Canal Morphology of Permanent Mandibular First Molars in a Sri Lankan Population

    Directory of Open Access Journals (Sweden)

    Roshan Peiris

    2015-01-01

    Full Text Available The present study was conducted to determine the number of roots and morphology of the root canal system of permanent mandibular first molars (M1 in a Sri Lankan population. Sample of 529 M1 teeth was used. The number of roots was examined and the lengths of the mesial and distal roots were measured to the nearest 0.01 mm. Vacuum injection protocol was used to inject China ink into the root canal system, making it transparent. Root canal morphology was recorded using Vertucci’s classification. Presence of furcation canals, position of lateral canals, intercanal communications, level of bifurcation, and convergence of the root canal system were recorded. M1 showed three roots in 4.1% of the sample. Commonest root canal morphology of the mesial root was type IV and the distal root was type I. The level of bifurcation of the root canals was commonly observed in the cervical one-third of the root while convergence was observed in the apical one-third in both roots. Prevalence of three rooted mandibular first molars is less than 5%. Mesial root showed the most variable canal morphology. Prevalence of furcation canals was 1.5% while that of middle mesial canals was 0.2%.

  19. Limb shortening osteotomy in a patient with achondroplasia and leg length difference after total hip arthroplasty

    Directory of Open Access Journals (Sweden)

    Christian L. Galata

    2013-07-01

    Full Text Available Introduction: Achondroplasia is the most common reason for disproportionate short stature. Normally, orthopedic limb lengthening procedures must be discussed in the course of this genetic disorder and have been successful in numerous achondroplastic patients in the past. In some cases, the disease may lead to leg length differences with need for surgical correction. Case Report: We report a case of achondroplastic dysplastic coxarthrosis with symptomatic leg length difference after bilateral total hip arthroplasty in a 52-year-old female patient, in which a distal femoral shortening osteotomy was successfully performed. Conclusion: Femoral shortening osteotomy is very uncommon in patients with achondroplasia. We conclude, however, that in rare cases it can be indicated and provide the advantage of shorter operation time, less perioperative complications and faster recovery compared to leg lengthening procedures. Keywords: Achondroplasia, dysplastic coxarthrosis, limb shortening, distal femur osteotomy.

  20. Identifying the transition to the maturation zone in three ecotypes of Arabidopsis thaliana roots.

    Science.gov (United States)

    Cajero Sánchez, Wendy; García-Ponce, Berenice; Sánchez, María de la Paz; Álvarez-Buylla, Elena R; Garay-Arroyo, Adriana

    2018-01-01

    The Arabidopsis thaliana (hereafter Arabidopsis) root has become a useful model for studying how organ morphogenesis emerge from the coordination and balance of cell proliferation and differentiation, as both processes may be observed and quantified in the root at different stages of development. Hence, being able to objectively identify and delimit the different stages of root development has been very important. Up to now, three different zones along the longitudinal axis of the primary root of Arabidopsis, have been identified: the root apical meristematic zone (RAM) with two domains [the proliferative (PD) and the transition domain (TD)], the elongation zone (EZ) and the maturation zone (MZ). We previously reported a method to quantify the length of the cells of the meristematic and the elongation zone, as well as the boundaries or transitions between the root domains along the growing part of the Arabidopsis root. In this study, we provide a more accurate criterion to identify the MZ. Traditionally, the transition between the EZ to the MZ has been established by the emergence of the first root-hair bulge in the epidermis, because this emergence coincides with cell maturation in this cell type. But we have found here that after the emergence of the first root-hair bulge some cells continue to elongate and we have confirmed this in three different Arabidopsis ecotypes. We established the limit between the EZ and the MZ by looking for the closest cortical cell with a longer length than the average cell length of 10 cells after the cortical cell closest to the epidermal cell with the first root-hair bulge in these three ecotypes. In Col-0 and Ws this cell is four cells above the one with the root hair bulge and, in the Ler ecotype, this cell is five cells above. To unambiguously identifying the site at which cells stop elongating and attain their final length and fate at the MZ, we propose to calculate the length of completely elongated cortical cells counting 10

  1. Topological analysis of polymeric melts: chain-length effects and fast-converging estimators for entanglement length.

    Science.gov (United States)

    Hoy, Robert S; Foteinopoulou, Katerina; Kröger, Martin

    2009-09-01

    Primitive path analyses of entanglements are performed over a wide range of chain lengths for both bead spring and atomistic polyethylene polymer melts. Estimators for the entanglement length N_{e} which operate on results for a single chain length N are shown to produce systematic O(1/N) errors. The mathematical roots of these errors are identified as (a) treating chain ends as entanglements and (b) neglecting non-Gaussian corrections to chain and primitive path dimensions. The prefactors for the O(1/N) errors may be large; in general their magnitude depends both on the polymer model and the method used to obtain primitive paths. We propose, derive, and test new estimators which eliminate these systematic errors using information obtainable from the variation in entanglement characteristics with chain length. The new estimators produce accurate results for N_{e} from marginally entangled systems. Formulas based on direct enumeration of entanglements appear to converge faster and are simpler to apply.

  2. Clonal Propagation of Khaya senegalensis: The Effects of Stem Length, Leaf Area, Auxins, Smoke Solution, and Stockplant Age

    Directory of Open Access Journals (Sweden)

    Catherine Ky-Dembele

    2011-01-01

    Full Text Available Khaya senegalensis is a multipurpose African timber species. The development of clonal propagation could improve plantation establishment, which is currently impeded by mahogany shoot borer. To examine its potential for clonal propagation, the effects of cutting length, leaf area, stockplant maturation, auxin, and smoke solution treatments were investigated. Leafy cuttings rooted well (up to 80% compared to leafless cuttings (0%. Cuttings taken from seedlings rooted well (at least 95%, but cuttings obtained from older trees rooted poorly (5% maximum. The rooting ability of cuttings collected from older trees was improved (16% maximum by pollarding. Auxin application enhanced root length and the number of roots while smoke solution did not improve cuttings' rooting ability. These results indicate that juvenile K. senegalensis is amenable to clonal propagation, but further work is required to improve the rooting of cuttings from mature trees.

  3. Surgical management of aortic root disease in Marfan syndrome and other congenital disorders associated with aortic root aneurysms

    NARCIS (Netherlands)

    T. Treasure (Tom); J.J.M. Takkenberg (Hanneke); J. Pepper (John)

    2014-01-01

    textabstractElective root replacement in Marfan syndrome has improved life expectancy in affected patients. Three forms of surgery are now available: total root replacement (TRR) with a valved conduit, valve sparing root replacement (VSRR) and personalised external aortic root support (PEARS) with a

  4. Surgical management of aortic root disease in Marfan syndrome and other congenital disorders associated with aortic root aneurysms

    NARCIS (Netherlands)

    T. Treasure (Tom); J.J.M. Takkenberg (Hanneke); J. Pepper (John)

    2016-01-01

    textabstractElective root replacement in Marfan syndrome has improved life expectancy in affected patients. Three forms of surgery are now available: total root replacement (TRR) with a valved conduit, valve sparing root replacement (VSRR) and personalised external aortic root support (PEARS) with a

  5. External apical root resorption in maxillary incisors in orthodontic patients: associated factors and radiographic evaluation.

    Science.gov (United States)

    Nanekrungsan, Kamonporn; Patanaporn, Virush; Janhom, Apirum; Korwanich, Narumanus

    2012-09-01

    This study was performed to evaluate the incidence and degree of external apical root resorption of maxillary incisors after orthodontic treatment and to evaluate particular associated factors related to external apical root resorption. The records and maxillary incisor periapical radiographs of 181 patients were investigated. Crown and root lengths were measured and compared on the pre- and post-treatment periapical radiographs. Crown length was measured from the center of the incisal edge to the midpoint of the cemento-enamel junction (CEJ). Root length was measured from the CEJ midpoint to the root apex. A correction factor for the enlargement difference was used to calculate root resorption. The periapical radiographs of 564 teeth showed that the average root resorption was 1.39±1.27 (8.24±7.22%) and 1.69±1.14 mm (10.16±6.78%) for the maxillary central and lateral incisors, respectively. The results showed that the dilacerated or pointed roots, maxillary premolar extraction cases, and treatment duration were highly significant factors for root resorption (proot resorption (proot resorption among the factors of gender, overbite, tongue-thrusting habit, types of malocclusion, and types of bracket. These results suggested that orthodontic treatment should be carefully performed in pre-treatment extraction patients who have pointed or dilacerated roots and need long treatment duration.

  6. The interaction between glucose and cytokinin signaling in controlling Arabidopsis thaliana seedling root growth and development.

    Science.gov (United States)

    Kushwah, Sunita; Laxmi, Ashverya

    2017-05-04

    Cytokinin (CK) and glucose (GLC) control several common responses in plants. There is an extensive overlap between CK and GLC signal transduction pathways in Arabidopsis. Physiologically, both GLC and CK could regulate root length in light. CK interacts with GLC via HXK1 dependent pathway for root length control. Wild-type (WT) roots cannot elongate in the GLC free medium while CK-receptor mutant ARABIDOPSIS HISTIDINE KINASE4 (ahk4) and type B ARR triple mutant ARABIDOPSIS RESPONSE REGULATOR1, 10,11 (arr1, 10,11) roots could elongate even in the absence of GLC as compared with the WT. The root hair initiation was also found defective in CK signaling mutants ahk4, arr1,10,11 and arr3,4,5,6,8,9 on increasing GLC concentration (up to 3%); and lesser number of root hairs were visible even at 5% GLC as compared with the WT. Out of 941 BAP regulated genes, 103 (11%) genes were involved in root growth and development. Out of these 103 genes, 60 (58%) genes were also regulated by GLC. GLC could regulate 5736 genes, which include 327 (6%) genes involved in root growth and development. Out of these 327 genes, 60 (18%) genes were also regulated by BAP. Both GLC and CK signaling cannot alter root length in light in auxin signaling mutant AUXIN RESPONSE3/INDOLE-3-ACETIC ACID17 (axr3/iaa17) suggesting that they may involve auxin signaling component as a nodal point. Therefore CK- and GLC- signaling are involved in controlling different aspects of root growth and development such as root length, with auxin signaling components working as downstream target.

  7. 3D Ground Penetrating Radar to Detect Tree Roots and Estimate Root Biomass in the Field

    Directory of Open Access Journals (Sweden)

    Shiping Zhu

    2014-06-01

    Full Text Available The objectives of this study were to detect coarse tree root and to estimate root biomass in the field by using an advanced 3D Ground Penetrating Radar (3D GPR system. This study obtained full-resolution 3D imaging results of tree root system using 500 MHz and 800 MHz bow-tie antennas, respectively. The measurement site included two larch trees, and one of them was excavated after GPR measurements. In this paper, a searching algorithm, based on the continuity of pixel intensity along the root in 3D space, is proposed, and two coarse roots whose diameters are more than 5 cm were detected and delineated correctly. Based on the detection results and the measured root biomass, a linear regression model is proposed to estimate the total root biomass in different depth ranges, and the total error was less than 10%. Additionally, based on the detected root samples, a new index named “magnitude width” is proposed to estimate the root diameter that has good correlation with root diameter compared with other common GPR indexes. This index also provides direct measurement of the root diameter with 13%–16% error, providing reasonable and practical root diameter estimation especially in the field.

  8. Root structure-function relationships in 74 species: evidence of a root economics spectrum related to carbon economy.

    Science.gov (United States)

    Roumet, Catherine; Birouste, Marine; Picon-Cochard, Catherine; Ghestem, Murielle; Osman, Normaniza; Vrignon-Brenas, Sylvain; Cao, Kun-Fang; Stokes, Alexia

    2016-05-01

    Although fine roots are important components of the global carbon cycle, there is limited understanding of root structure-function relationships among species. We determined whether root respiration rate and decomposability, two key processes driving carbon cycling but always studied separately, varied with root morphological and chemical traits, in a coordinated way that would demonstrate the existence of a root economics spectrum (RES). Twelve traits were measured on fine roots (diameter ≤ 2 mm) of 74 species (31 graminoids and 43 herbaceous and dwarf shrub eudicots) collected in three biomes. The findings of this study support the existence of a RES representing an axis of trait variation in which root respiration was positively correlated to nitrogen concentration and specific root length and negatively correlated to the root dry matter content, lignin : nitrogen ratio and the remaining mass after decomposition. This pattern of traits was highly consistent within graminoids but less consistent within eudicots, as a result of an uncoupling between decomposability and morphology, and of heterogeneity of individual roots of eudicots within the fine-root pool. The positive relationship found between root respiration and decomposability is essential for a better understanding of vegetation-soil feedbacks and for improving terrestrial biosphere models predicting the consequences of plant community changes for carbon cycling. © 2016 CNRS. New Phytologist © 2016 New Phytologist Trust.

  9. Genetic Loci Governing Grain Yield and Root Development under Variable Rice Cultivation Conditions

    Directory of Open Access Journals (Sweden)

    Margaret Catolos

    2017-10-01

    Full Text Available Drought is the major abiotic stress to rice grain yield under unpredictable changing climatic scenarios. The widely grown, high yielding but drought susceptible rice varieties need to be improved by unraveling the genomic regions controlling traits enhancing drought tolerance. The present study was conducted with the aim to identify quantitative trait loci (QTLs for grain yield and root development traits under irrigated non-stress and reproductive-stage drought stress in both lowland and upland situations. A mapping population consisting of 480 lines derived from a cross between Dular (drought-tolerant and IR64-21 (drought susceptible was used. QTL analysis revealed three major consistent-effect QTLs for grain yield (qDTY1.1, qDTY1.3, and qDTY8.1 under non-stress and reproductive-stage drought stress conditions, and 2 QTLs for root traits (qRT9.1 for root-growth angle and qRT5.1 for multiple root traits, i.e., seedling-stage root length, root dry weight and crown root number. The genetic locus qDTY1.1 was identified as hotspot for grain yield and yield-related agronomic and root traits. The study identified significant positive correlations among numbers of crown roots and mesocotyl length at the seedling stage and root length and root dry weight at depth at later stages with grain yield and yield-related traits. Under reproductive stage drought stress, the grain yield advantage of the lines with QTLs ranged from 24.1 to 108.9% under upland and 3.0–22.7% under lowland conditions over the lines without QTLs. The lines with QTL combinations qDTY1.3+qDTY8.1 showed the highest mean grain yield advantage followed by lines having qDTY1.1+qDTY8.1 and qDTY1.1+qDTY8.1+qDTY1.3, across upland/lowland reproductive-stage drought stress. The identified QTLs for root traits, mesocotyl length, grain yield and yield-related traits can be immediately deployed in marker-assisted breeding to develop drought tolerant high yielding rice varieties.

  10. Linking root traits to nutrient foraging in arbuscular mycorrhizal trees in a temperate forest.

    Science.gov (United States)

    Eissenstat, David M; Kucharski, Joshua M; Zadworny, Marcin; Adams, Thomas S; Koide, Roger T

    2015-10-01

    The identification of plant functional traits that can be linked to ecosystem processes is of wide interest, especially for predicting vegetational responses to climate change. Root diameter of the finest absorptive roots may be one plant trait that has wide significance. Do species with relatively thick absorptive roots forage in nutrient-rich patches differently from species with relatively fine absorptive roots? We measured traits related to nutrient foraging (root morphology and architecture, root proliferation, and mycorrhizal colonization) across six coexisting arbuscular mycorrhizal (AM) temperate tree species with and without nutrient addition. Root traits such as root diameter and specific root length were highly correlated with root branching intensity, with thin-root species having higher branching intensity than thick-root species. In both fertilized and unfertilized soil, species with thin absorptive roots and high branching intensity showed much greater root length and mass proliferation but lower mycorrhizal colonization than species with thick absorptive roots. Across all species, fertilization led to increased root proliferation and reduced mycorrhizal colonization. These results suggest that thin-root species forage more by root proliferation, whereas thick-root species forage more by mycorrhizal fungi. In mineral nutrient-rich patches, AM trees seem to forage more by proliferating roots than by mycorrhizal fungi. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  11. Incidence and severity of root resorption in orthodontically moved premolars in dogs.

    Science.gov (United States)

    Maltha, J C; van Leeuwen, E J; Dijkman, G E H M; Kuijpers-Jagtman, A M

    2004-05-01

    To study treatment-related factors for external root resorption during orthodontic tooth movement. An experimental animal study. Department of Orthodontics and Oral Biology, University Medical Centre Nijmegen, The Netherlands. Twenty-four young adult beagle dogs. Mandibular premolars were bodily moved with continuous or intermittent controlled orthodontic forces of 10, 25, 50, 100, or 200 cN according to standardized protocols. At different points in time histomorphometry was performed to determine the severity of root resorption. Prevalence of root resorptions, defined as microscopically visible resorption lacunae in the dentin. Severity of resorption was defined by the length, relative length, depth, and surface area of each resorption area. The incidence of root resorption increased with the duration of force application. After 14-17 weeks of force application root resorption was found at 94% of the root surfaces at pressure sides. The effect of force magnitude on the severity of root resorption was not statistically significant. The severity of root resorption was highly related to the force regimen. Continuous forces caused significantly more severe root resorption than intermittent forces. A strong correlation (0.60 < r < 0.68) was found between the amount of tooth movement and the severity of root resorption. Root resorption increases with the duration of force application. The more teeth are displaced, the more root resorption will occur. Intermittent forces cause less severe root resorption than continuous forces, and force magnitude is probably not decisive for root resorption.

  12. Predisposing factors to severe external root resorption associated to orthodontic treatment.

    Science.gov (United States)

    Picanço, Gracemia Vasconcelos; de Freitas, Karina Maria Salvatore; Cançado, Rodrigo Hermont; Valarelli, Fabricio Pinelli; Picanço, Paulo Roberto Barroso; Feijão, Camila Pontes

    2013-01-01

    The aim of this study was to evaluate predisposing factors among patients who developed moderate or severe external root resorption (Malmgren's grades 3 and 4), on the maxillary incisors, during fixed orthodontic treatment in the permanent dentition. Ninety-nine patients who underwent orthodontic treatment with fixed edgewise appliances were selected. Patients were divided into two groups: G1 - 50 patients with no root resorption or presenting only apical irregularities (Malmgren's grades 0 and 1) at the end of the treatment, with mean initial age of 16.79 years and mean treatment time of 3.21 years; G2 - 49 patients presenting moderate or severe root resorption (Malmgren's grades 3 and 4) at the end of treatment on the maxillary incisors, with mean initial age of 19.92 years and mean treatment time of 3.98 years. Periapical radiographs and lateral cephalograms were evaluated. Factors that could influence the occurrence of severe root resorption were also recorded. Statistical analysis included chi-square tests, Fisher's exact test and independent t tests. The results demonstrated significant difference between the groups for the variables: Extractions, initial degree of root resorption, root length and crown/root ratio at the beginning, and cortical thickness of the alveolar bone. It can be concluded that: Presence of root resorption before the beginning of treatment, extractions, reduced root length, decreased crown/root ratio and thin alveolar bone represent risk factors for severe root resorption in maxillary incisors during orthodontic treatment.

  13. Rooting traits of peanut genotypes with different yield response to terminal drought

    Science.gov (United States)

    Drought at pod filling and maturity stages can severely reduce yield of peanut. Better root systems can reduce yield loss from drought. The goal of this study was to investigate the responses to terminal drought of peanut genotypes for root dry weight and root length density. A field experiment was ...

  14. Chitosan Increases Tomato Root Colonization by Pochonia chlamydosporia and Their Combination Reduces Root-Knot Nematode Damage

    Directory of Open Access Journals (Sweden)

    Nuria Escudero

    2017-09-01

    Full Text Available The use of biological control agents could be a non-chemical alternative for management of Meloidogyne spp. [root-knot nematodes (RKN], the most damaging plant-parasitic nematodes for horticultural crops worldwide. Pochonia chlamydosporia is a fungal parasite of RKN eggs that can colonize endophytically roots of several cultivated plant species, but in field applications the fungus shows a low persistence and efficiency in RKN management. The combined use of P. chlamydosporia with an enhancer could help its ability to develop in soil and colonize roots, thereby increasing its efficiency against nematodes. Previous work has shown that chitosan enhances P. chlamydosporia sporulation and production of extracellular enzymes, as well as nematode egg parasitism in laboratory bioassays. This work shows that chitosan at low concentrations (up to 0.1 mg ml-1 do not affect the viability and germination of P. chlamydosporia chlamydospores and improves mycelial growth respect to treatments without chitosan. Tomato plants irrigated with chitosan (same dose limit increased root weight and length after 30 days. Chitosan irrigation increased dry shoot and fresh root weight of tomato plants inoculated with Meloidogyne javanica, root length when they were inoculated with P. chlamydosporia, and dry shoot weight of plants inoculated with both P. chlamydosporia and M. javanica. Chitosan irrigation significantly enhanced root colonization by P. chlamydosporia, but neither nematode infection per plant nor fungal egg parasitism was affected. Tomato plants cultivated in a mid-suppressive (29.3 ± 4.7% RKN egg infection non-sterilized clay loam soil and irrigated with chitosan had enhanced shoot growth, reduced RKN multiplication, and disease severity. Chitosan irrigation in a highly suppressive (73.7 ± 2.6% RKN egg infection sterilized-sandy loam soil reduced RKN multiplication in tomato. However, chitosan did not affect disease severity or plant growth irrespective of

  15. QTL meta-analysis of root traits in Brassica napus under contrasting phosphorus supply in two growth systems.

    Science.gov (United States)

    Zhang, Ying; Thomas, Catherine L; Xiang, Jinxia; Long, Yan; Wang, Xiaohua; Zou, Jun; Luo, Ziliang; Ding, Guangda; Cai, Hongmei; Graham, Neil S; Hammond, John P; King, Graham J; White, Philip J; Xu, Fangsen; Broadley, Martin R; Shi, Lei; Meng, Jinling

    2016-09-14

    A high-density SNP-based genetic linkage map was constructed and integrated with a previous map in the Tapidor x Ningyou7 (TNDH) Brassica napus population, giving a new map with a total of 2041 molecular markers and an average marker density which increased from 0.39 to 0.97 (0.82 SNP bin) per cM. Root and shoot traits were screened under low and 'normal' phosphate (Pi) supply using a 'pouch and wick' system, and had been screened previously in an agar based system. The P-efficient parent Ningyou7 had a shorter primary root length (PRL), greater lateral root density (LRD) and a greater shoot biomass than the P-inefficient parent Tapidor under both treatments and growth systems. Quantitative trait loci (QTL) analysis identified a total of 131 QTL, and QTL meta-analysis found four integrated QTL across the growth systems. Integration reduced the confidence interval by ~41%. QTL for root and shoot biomass were co-located on chromosome A3 and for lateral root emergence were co-located on chromosomes A4/C4 and C8/C9. There was a major QTL for LRD on chromosome C9 explaining ~18% of the phenotypic variation. QTL underlying an increased LRD may be a useful breeding target for P uptake efficiency in Brassica.

  16. Length-weight and length-length relationships of common carp (Cyprinus carpio L.) in the middle and southern Iraq provinces

    Science.gov (United States)

    Al-jebory, Taymaa A.; Das, Simon K.; Usup, Gires; Bakar, Y.; Al-saadi, Ali H.

    2018-04-01

    In this study, length-weight and length-length relationships of common carp (Cyprinus carpio L.) in the middle and southern Iraq provinces were determined. Fish specimens were procured from seven provinces from July to December, 2015. A negative and positive allometric growth pattern was obtained, where the total length (TL) ranged from 25.60 cm to 33.53 cm, and body weight (BW) ranged from 700 g to 1423 g. Meanwhile, the lowest of 1.03 and highest of 3.54 in "b" value was recorded in group F and group C, respectively. Therefore, Fulton condition factor (K) range from 2.57 to 4.94. While, relative condition factor (Kn) was in the ranged of 0.95 to 1.01. A linear relationship between total length (TL) and standard length (SL) among the provinces for fish groups was obtained. The variances in "b" value ranged from 0.10 to 0.93 with correlation coefficient (r2) of 0.02 to 0.97. This research could be used as a guide to study the ecology and biology of common Carp (Cyprinus carpio L.) in the middle and southern Iraq provinces.

  17. External apical root resorption in maxillary incisors in orthodontic patients: associated factors and radiographic evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Nanekrungsan, Kamonporn [Dept. of Dentistry, Overbrook Hospital, Chiang Rai (Thailand); Patanaporn, Virush; Janhom, Apirum; Korwanich, Narumanus [Dept. of Chiang Mai University, Chiang Mai (Thailand)

    2012-09-15

    This study was performed to evaluate the incidence and degree of external apical root resorption of maxillary incisors after orthodontic treatment and to evaluate particular associated factors related to external apical root resorption. The records and maxillary incisor periapical radiographs of 181 patients were investigated. Crown and root lengths were measured and compared on the pre- and post-treatment periapical radiographs. Crown length was measured from the center of the incisal edge to the midpoint of the cemento-enamel junction (CEJ). Root length was measured from the CEJ midpoint to the root apex. A correction factor for the enlargement difference was used to calculate root resorption. The periapical radiographs of 564 teeth showed that the average root resorption was 1.39{+-}1.27 (8.24{+-}7.22%) and 1.69{+-}1.14 mm (10.16{+-}6.78%) for the maxillary central and lateral incisors, respectively. The results showed that the dilacerated or pointed roots, maxillary premolar extraction cases, and treatment duration were highly significant factors for root resorption (p<0.001). Allergic condition was a significant factor at p<0.01. Age at the start of treatment, large overjet, and history of facial trauma were also factors significantly associated with root resorption (p<0.05). There was no statistically significant difference in root resorption among the factors of gender, overbite, tongue-thrusting habit, types of malocclusion, and types of bracket. These results suggested that orthodontic treatment should be carefully performed in pre-treatment extraction patients who have pointed or dilacerated roots and need long treatment duration.

  18. External apical root resorption in maxillary incisors in orthodontic patients: associated factors and radiographic evaluation

    International Nuclear Information System (INIS)

    Nanekrungsan, Kamonporn; Patanaporn, Virush; Janhom, Apirum; Korwanich, Narumanus

    2012-01-01

    This study was performed to evaluate the incidence and degree of external apical root resorption of maxillary incisors after orthodontic treatment and to evaluate particular associated factors related to external apical root resorption. The records and maxillary incisor periapical radiographs of 181 patients were investigated. Crown and root lengths were measured and compared on the pre- and post-treatment periapical radiographs. Crown length was measured from the center of the incisal edge to the midpoint of the cemento-enamel junction (CEJ). Root length was measured from the CEJ midpoint to the root apex. A correction factor for the enlargement difference was used to calculate root resorption. The periapical radiographs of 564 teeth showed that the average root resorption was 1.39±1.27 (8.24±7.22%) and 1.69±1.14 mm (10.16±6.78%) for the maxillary central and lateral incisors, respectively. The results showed that the dilacerated or pointed roots, maxillary premolar extraction cases, and treatment duration were highly significant factors for root resorption (p<0.001). Allergic condition was a significant factor at p<0.01. Age at the start of treatment, large overjet, and history of facial trauma were also factors significantly associated with root resorption (p<0.05). There was no statistically significant difference in root resorption among the factors of gender, overbite, tongue-thrusting habit, types of malocclusion, and types of bracket. These results suggested that orthodontic treatment should be carefully performed in pre-treatment extraction patients who have pointed or dilacerated roots and need long treatment duration.

  19. Improvement of date palm plant lets during rooting stage by silver ion

    International Nuclear Information System (INIS)

    Sharaf, M.M.; Khamis, M.A.; El Bana, A.; Abd El Galeil, L.M.; Zaid, Z.E.

    2012-01-01

    This study aim to promote growth plant lets of date palm cv. Zaghlool by decreasing ethylene production inside the containers during rooting stage. Data obtained declared that three silver thiosulphate (STS) levels added to one half strength MS rooting medium improved significantly three rooting measurements (rooting percentage; number and length of developed root lets). However, the lightest STS level (0.25 ml/L of 4 mM STS solution) was the superior, while highest one (1.0 ml/L) was the inferior from statistical point of view. Data obtained displayed that providing MS rooting medium with silver nitrate improved 3 rooting measurements (rooting %; number of root lets and their length) for Zaghloul date palm shoot lets proliferated from somatic embryos. However, the 0.50 mg/L AgNO 3 provided MS medium was the most preferable in this concern. Plant lets were transferred to capped tubes contained 1/4 liquid MS medium through 3 weeks in the growth chamber (under aseptic condition). Ventilation was allowed gradually by punching holes in aluminum foil caps during first five days of 2 nd week. After then, the plant lets were transplanted in acclimatization green house on mixture from (peat moss + perlite + vermiculite at 1:1:1) and survival percentage was 75% after three months.

  20. Protective effects of total extracts of Averrhoa carambola L. (Oxalidaceae) roots on streptozotocin-induced diabetic mice.

    Science.gov (United States)

    Xu, Xiaohui; Liang, Tao; Wen, Qingwei; Lin, Xing; Tang, Jingzhi; Zuo, Qiaoyun; Tao, Liqun; Xuan, Feifei; Huang, Renbin

    2014-01-01

    In Chinese culture, the roots of Averrhoa carambola L. have long been used for medical purposes due to their potent pharmaceutical activities, such as improving digestive function and treating diabetes. Recently, we prepared extracts of Averrhoa carambola L. root (EACR), which were isolated from Averrhoa carambola L. roots using ethanol or water. This study was designed to investigate the potential effects of EACR on streptozotocin (STZ) diabetic mice and to explore the underlying mechanism of these effects. Male mice were injected with STZ through the tail vein (120 mg/kg body weight) and were identified as a diabetic mouse model when the level of blood glucose was ≥11.1 mmol/L. Subsequently, the mice were administered EACR (150, 300, 600, 1200 mg/kg body weight/d) and metformin (320 mg/kg body weight/d) via intragastric gavage for three weeks. The results indicated that EACR significantly decreased the serum levels of blood glucose, total cholesterol (TC), triglycerides (TGs) and free fatty acids (FFAs), whereas the content of serum insulin was elevated. In addition, the expressions of apoptosis-related regulators (including caspase-3, caspase-8 and caspase-9) and the apoptosis-induced protein Bax were markedly down-regulated by EACR, whereas the expression of the anti-apoptotic Bcl-2 protein was notably increased. Furthermore, EACR could protect the diabetic mice against the STZ-induced apoptosis of pancreatic β cells. Taken together, these findings indicate that EACR plays an effective hyperglycemic role that is associated with ameliorating metabolic functions and with inhibiting apoptosis in pancreas tissue. © 2014 S. Karger AG, Basel.

  1. Protective Effects of Total Extracts of Averrhoa carambola L. (Oxalidaceae Roots on Streptozotocin-Induced Diabetic Mice

    Directory of Open Access Journals (Sweden)

    Xiaohui Xu

    2014-04-01

    Full Text Available Background: In Chinese culture, the roots of Averrhoa carambola L. have long been used for medical purposes due to their potent pharmaceutical activities, such as improving digestive function and treating diabetes. Methods: Recently, we prepared extracts of Averrhoa carambola L. root (EACR, which were isolated from Averrhoa carambola L. roots using ethanol or water. This study was designed to investigate the potential effects of EACR on streptozotocin (STZ diabetic mice and to explore the underlying mechanism of these effects. Male mice were injected with STZ through the tail vein (120 mg/kg body weight and were identified as a diabetic mouse model when the level of blood glucose was ≥11.1 mmol/L. Subsequently, the mice were administered EACR (150, 300, 600, 1200 mg/kg body weight/d and metformin (320 mg/kg body weight/d via intragastric gavage for three weeks. Results: The results indicated that EACR significantly decreased the serum levels of blood glucose, total cholesterol (TC, triglycerides (TGs and free fatty acids (FFAs, whereas the content of serum insulin was elevated. In addition, the expressions of apoptosis-related regulators (including caspase-3, caspase-8 and caspase-9 and the apoptosis-induced protein Bax were markedly down-regulated by EACR, whereas the expression of the anti-apoptotic Bcl-2 protein was notably increased. Furthermore, EACR could protect the diabetic mice against the STZ-induced apoptosis of pancreatic β cells. Conclusion: Taken together, these findings indicate that EACR plays an effective hyperglycemic role that is associated with ameliorating metabolic functions and with inhibiting apoptosis in pancreas tissue.

  2. Effects of elevated root zone CO2 and air temperature on photosynthetic gas exchange, nitrate uptake, and total reduced nitrogen content in aeroponically grown lettuce plants.

    Science.gov (United States)

    He, Jie; Austin, Paul T; Lee, Sing Kong

    2010-09-01

    Effects of elevated root zone (RZ) CO(2) and air temperature on photosynthesis, productivity, nitrate (NO(3)(-)), and total reduced nitrogen (N) content in aeroponically grown lettuce plants were studied. Three weeks after transplanting, four different RZ [CO(2)] concentrations [ambient (360 ppm) and elevated concentrations of 2000, 10,000, and 50,000 ppm] were imposed on plants grown at two air temperature regimes of 28 degrees C/22 degrees C (day/night) and 36 degrees C/30 degrees C. Photosynthetic CO(2) assimilation (A) and stomatal conductance (g(s)) increased with increasing photosynthetically active radiation (PAR). When grown at 28 degrees C/22 degrees C, all plants accumulated more biomass than at 36 degrees C/30 degrees C. When measured under a PAR >or=600 micromol m(-2) s(-1), elevated RZ [CO(2)] resulted in significantly higher A, lower g(s), and higher midday leaf relative water content in all plants. Under elevated RZ [CO(2)], the increase of biomass was greater in roots than in shoots, causing a lower shoot/root ratio. The percentage increase in growth under elevated RZ [CO(2)] was greater at 36 degrees C/30 degrees C although the total biomass was higher at 28 degrees C/22 degrees C. NO(3)(-) and total reduced N concentrations of shoot and root were significantly higher in all plants under elevated RZ [CO(2)] than under ambient RZ [CO(2)] of 360 ppm at both temperature regimes. At each RZ [CO(2)], NO(3)(-) and total reduced N concentration of shoots were greater at 28 degrees C/22 degrees C than at 36 degrees C/30 degrees C. At all RZ [CO(2)], roots of plants at 36 degrees C/30 degrees C had significantly higher NO(3)(-) and total reduced N concentrations than at 28 degrees C/22 degrees C. Since increased RZ [CO(2)] caused partial stomatal closure, maximal A and maximal g(s) were negatively correlated, with a unique relationship for each air temperature. However, across all RZ [CO(2)] and temperature treatments, there was a close correlation between

  3. Genetic Variation in Deep Root Growth of North-European Winter Wheat

    DEFF Research Database (Denmark)

    Ytting, Nanna Karkov

    no correlation between root length density in the subsoil and shoot N content was found at higher subsoil N levels (> 12.5 mg N kg-1 soil). Shoot size and especially average tiller size was highly correlated to subsoil root density (R2 = 0.26 – 0.37, p ≤ 0.001). Low N levels (... and environments, as the interaction between genotypes and environment is substantial for most root traits. Root quantification with the line intersect method can be optimized by choosing the right strategy when scoring the root traits. For example, by adapting counting grids to match specific root densities, data...

  4. Evaluation of apical root resorption in orthodontic patients with maxillary anterior intrusion using utility arches and mini screws: A comparative clinical trial

    Directory of Open Access Journals (Sweden)

    Muraleedhara Bhat

    2014-01-01

    Full Text Available Objectives: The purpose of this study was to compare the amount of apical root resorption in orthodontic patients undergoing maxillary anterior intrusion using utility arches and mini screws; and to compare the efficacy of mini screws and utility arches in reducing over bite. Materials and Methods: The study sample consisted of 20 patients, divided in two groups. Group A consisted of ten patients in whom titanium mini-screws were used Group B consisted of 10 patients in whom utility arches made of 0.017 × 0.25" TMA were used. Diagnostic records (study models and radiovisiography [RVG] were taken at 2 time intervals, T1 (just before implant/utility arch placement and T2 (at the end of intrusion 6 months later. The pre and post radiographic images were measured from incisal tip to the root apex with the help of intrascan DC software. Root resorption was computed as the difference between the pre-treatment total tooth length and the post treatment total tooth length. These values were subjected to statistical analyses using SPSS 16.00 statistical software. (Statistical Package for the Social Sciences, IBM Corporation, December 2007 Results: The results showed that root resorption was seen in both groups. Amount of resorption seen was higher in mini implant group than utility arch group. Mini implants were more efficient in reducing the overbite when compared to utility arches. Conclusion: It was concluded from the study that intrusion using mini implant resulted in more root resorption than utility arch; and mini implant was more effective in intruding the incisors than utility arch.

  5. Rooting characteristics of Solanum chacoense and Solanum tuberosum in vitro

    Science.gov (United States)

    Increases in root biomass and length have been linked to increased plant nitrogen (N) accumulation; however it is difficult to measure these parameters in soil environments. In vitro methods may aid in elucidating potato-rooting characteristics in relation to N use efficiency (NUE) due to a high lev...

  6. RNA-seq for gene identification and transcript profiling in relation to root growth of bermudagrass (Cynodon dactylon) under salinity stress.

    Science.gov (United States)

    Hu, Longxing; Li, Huiying; Chen, Liang; Lou, Yanhong; Amombo, Erick; Fu, Jinmin

    2015-08-04

    Soil salinity is one of the most significant abiotic stresses affecting plant shoots and roots growth. The adjustment of root architecture to spatio-temporal heterogeneity in salinity is particularly critical for plant growth and survival. Bermudagrass (Cynodon dactylon) is a widely used turf and forage perennial grass with a high degree of salinity tolerance. Salinity appears to stimulate the growth of roots and decrease their mortality in tolerant bermudagrass. To estimate a broad spectrum of genes related to root elongation affected by salt stress and the molecular mechanisms that control the positive response of root architecture to salinity, we analyzed the transcriptome of bermudagrass root tips in response to salinity. RNA-sequencing was performed in root tips of two bermudagrass genotypes contrasting in salt tolerance. A total of 237,850,130 high quality clean reads were generated and 250,359 transcripts were assembled with an average length of 1115 bp. Totally, 103,324 unigenes obtained with 53,765 unigenes (52 %) successfully annotated in databases. Bioinformatics analysis indicated that major transcription factor (TF) families linked to stress responses and growth regulation (MYB, bHLH, WRKY) were differentially expressed in root tips of bermudagrass under salinity. In addition, genes related to cell wall loosening and stiffening (xyloglucan endotransglucosylase/hydrolases, peroxidases) were identified. RNA-seq analysis identified candidate genes encoding TFs involved in the regulation of lignin synthesis, reactive oxygen species (ROS) homeostasis controlled by peroxidases, and the regulation of phytohormone signaling that promote cell wall loosening and therefore root growth under salinity.

  7. Using Upland Rice Root Traits to Identify N Use Efficient Genotypes for Limited Soil Nutrient Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Traore, K.; Traore, O. [INERA / Station de Farakoba, Bobo-Dioulasso (Burkina Faso); Bado, V. B. [Africa Rice Center (AfricaRice), Saint Louis (Senegal)

    2013-11-15

    Crop production in the Sahelian countries of Africa is limited by many factors. The most important are low potential yields of local varieties, low inherent soil fertility and low applications of external inputs (organic and mineral fertilizers). A field experiment was conducted from 2007 to 2008 with the objective to develop and validate screening protocols for plant traits that enhance N acquisition and utilization in upland rice grown in low N soils of two hundred (200) upland rice (Oryza sativa L.) genotypes from WAB, NERICA, CNA, CNAX, IRAT and IR lines. An experiment in small pots was carried out in a greenhouse of Farakoba research center. The pots were filled with a sandy soil and upland rice genotypes were grown during three weeks, harvested and studied for their root characteristics (seminal root length, adventitious root number, lateral root length and number and roots hair density). The small pot method was reliable for root trait characterisation at the seedling stage. A large variability among genotypes was exhibited for the root characteristics. The variability was larger within the NERICA and WAB lines compared to the other lines. The length of the seminal roots varied from 10 to 40 cm, the lateral root number ranged between 3 and 15 and the number of adventitious roots varied between 2 and 7. The selected root traits can be used to identify high nutrients and water use efficient genotypes. (author)

  8. Evaluation and Selection of Common Bean (Phaseolus Vulgaris L.) Genotypes for Root Traits Associated with Phosphorus (P) Acquisition Efficiency and the Use of {sup 32}P Isotope in Studies on P Uptake by Root Hairs

    Energy Technology Data Exchange (ETDEWEB)

    Miguel, M. A.; Jochua, C. [Agricultural Research Institute of Mozambique (IIAM), Maputo (Mozambique); Lynch, J. P. [Pennsylvania State University, University Park, PA (United States)

    2013-11-15

    Low phosphorus (P) availability is one of the main edaphic constraints limiting crop production and productivity in most of the tropical agro-ecosystems. Several root traits are known to be associated with P acquisition efficiency in low P soils. These root traits include root hairs. Computer modeling, laboratory and field studies show the depletion of {sup 32}P-phosphate around roots and that the depletion zone is influenced by the length and density of root hairs. We conducted a study involving a series of experiments with the objective of evaluating the variability of root traits associated with P uptake efficiency among common bean (Phaseolus vulgaris L.) genotypes, and to understand the mechanisms of long root hairs leading to the increase in P uptake in common bean. The study included (a) the screening of common bean genotypes in the laboratory and in the field for root traits, and (b) the use of radioactive phosphorus ({sup 32}P) in the experiments conducted in the greenhouse. For laboratory screening, seedlings were germinated in paper rolls in a growth media for 3 days before evaluation for basal root whorl number (BRWN), basal root number (BRN), basal root growth angle (BRGA) and root hair length (RHL). Common bean genotypes were planted in the field with low P for 45 days after planting (DAP) before evaluation. For the {sup 32}P study four contrasting genotypes for root hairs were grown for 28 DAP in the greenhouse using 15-20 liter pots filled with a mixture of sand and vermiculate as the growth media. The radioactive P was incorporated in the growth medium in the form of alumina-P fertilizer. Normal phosphorus (non-radioactive {sup 31}P) was included in the nutrient solution in the form of calcium phosphate, Ca{sub 3}(PO{sub 4}){sub 2}, and supplied through irrigation. Screened genotypes exhibited different root traits associated with P uptake efficiency, and that a given genotype can have one or more root traits responsible for it P uptake efficiency

  9. Uptake of 3HHO and 32P by roots of wheat and rape

    International Nuclear Information System (INIS)

    Bole, J.B.

    1977-01-01

    Direct measurements were made of 3 HHO and 32 P taken up from labelled soil by roots of wheat (Triticum aestivum L.) and rape (Brassica campestris L.). Single roots were encased in labelled soil for 3 days, and the amount of 3 HHO and 32 P retained in the shoots was determined. Plants were grown to five stages of maturity in growth boxes under controlled conditions. Roots were labelled at up to four depths (to 90 cm) depending on the rooting depth at each stage of maturity. Uptake of 3 HHP per unit length of root increased as the plant age increased, while uptake of 32 P decreased to below detection levels by 45 days after germination. Larger amounts of both nutrients were translocated to and retained in the shoots from surface roots than from roots located deeper in the soil although the soil was uniform in temperature, bulk density, and composition through the growth boxes. Wheat roots were more efficient than rape roots in absorbing 3 HHO; however, rape roots took up larger amounts of 32 P per unit length of root. Neither native nor added P located more than 30 cm deep is of much importance to these annual crops, since uptake is minimal and the main demand for this nutrient occurs at early growth stages when the root system is restricted to the surface layers

  10. Identification of quantitative trait loci controlling root and shoot traits associated with drought tolerance in a lentil (Lens culinaris Medik. recombinant inbred line population

    Directory of Open Access Journals (Sweden)

    Omar Idrissi

    2016-08-01

    Full Text Available Drought is one of the major abiotic stresses limiting lentil productivity in rainfed production systems. Specific rooting patterns can be associated with drought avoidance mechanisms that can be used in lentil breeding programs. In all, 252 co-dominant and dominant markers were used for Quantitative Trait Loci (QTL analysis on 132 lentil recombinant inbred lines based on greenhouse experiments for root and shoot traits during two seasons under progressive drought-stressed conditions. Eighteen QTLs controlling a total of 14 root and shoot traits were identified. A QTL-hotspot genomic region related to a number of root and shoot characteristics associated with drought tolerance such as dry root biomass, root surface area, lateral root number, dry shoot biomass and shoot length was identified. Interestingly, a QTL related to root-shoot ratio, an important trait for drought avoidance, explaining the highest phenotypic variance of 27.6 % and 28.9 % for the two consecutive seasons, respectively, was detected. This QTL was closed to the co-dominant SNP marker TP6337 and also flanked by the two SNP TP518 and TP1280. An important QTL related to lateral root number was found close to TP3371 and flanked by TP5093 and TP6072 SNP markers. Also, a QTL associated with specific root length was identified close to TP1873 and flanked by F7XEM6b SRAP marker and TP1035 SNP marker. These two QTLs were detected in both seasons. Our results could be used for marker-assisted selection in lentil breeding programs targeting root and shoot characteristics conferring drought avoidance as an efficient alternative to slow and labour-intensive conventional breeding methods.

  11. The Use of Antioxidants to Control Root Rot and Wilt Diseases of Pepper

    Directory of Open Access Journals (Sweden)

    Montaser Fawzy ABDEL-MONAIM

    2010-06-01

    Full Text Available Ten isolates of Fusarium spp were isolated from pepper plants collected from different locations in New Valley Governorate, Egypt. Fusarium solani isolate FP2 and F. oxysporum isolate FP4 were highly pathogenic isolates but the other isolates moderate or less pathogenic to pepper plants (cv. Anaheim-M. The four antioxidant compounds (coumaric acid, citric acid, propylgalate and salicylic acid each at 100 and 200 ppm were evaluated for their in vitro and in vivo agonist to Fusarium pathogenic isolates caused root rot and wilt diseases in pepper plants. All tested antioxidant compounds reduced damping-off, root rot/wilt and area under root rot/wilt progress curve when used as seed soaking, seedling soaking, and soil drench especially at 200 ppm under greenhouse and field conditions compared with untreated plants. All chemicals increased fresh and dry weight of seedling grown in soil drenching or seed treatment with any antioxidants. At the same time, all tested chemicals significantly increase plant growth parameters i.e plant length, plant branching, and total yield per plant in case of seedling soaking or soil drench. In general, propylgalate at 200 ppm was more efficient in reducing infection with damping-off, root rot and wilt diseases as well as increasing the seedling fresh weight, dry weight, plant length, plant branching, number of pod plant-1 and pod yield plant-1. On the other hand, all tested antioxidants had less or no effect on mycelial dry weight and mycelial leaner growth. On the contrary, all chemicals much reduced spore formation in both Fusarium species at 100 or 200 ppm and the inhibitory effect of antioxidants increased with increasing their concentrations.

  12. Effect of medium and post-irradiation storage on rooting of irradiated onions

    International Nuclear Information System (INIS)

    Singh, Rita

    2000-01-01

    Rooting test for detection of irradiation in onion bulbs was studied. Onions were exposed to different dose levels of 30, 60, 90, 120 and 150 Gy. The effects of irradiation dose, cultivar difference, rooting medium and post-irradiation storage on the rooting were investigated. The number and the length of the roots formed in onions were found to decrease on irradiation. The effect was more at higher doses. The effect of irradiation on rooting was also evident after 120 days of storage. (author)

  13. Bud removal affects shoot, root, and callus development of hardwood Populus cuttings

    Science.gov (United States)

    A.H. Wiese; J.A. Zalesny; D.M. Donner; Ronald S., Jr. Zalesny

    2006-01-01

    The inadvertent removal and/or damage of buds during processing and planting of hardwood poplar (Populus spp.) cuttings are a concern because of their potential impact on shoot and root development during establishment. The objective of the current study was to test for differences in shoot dry mass, root dry mass, number of roots, length of the...

  14. Information-theoretic lengths of Jacobi polynomials

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero, A; Dehesa, J S [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Granada, Granada (Spain); Sanchez-Moreno, P, E-mail: agmartinez@ugr.e, E-mail: pablos@ugr.e, E-mail: dehesa@ugr.e [Instituto ' Carlos I' de Fisica Teorica y Computacional, Universidad de Granada, Granada (Spain)

    2010-07-30

    The information-theoretic lengths of the Jacobi polynomials P{sup ({alpha}, {beta})}{sub n}(x), which are information-theoretic measures (Renyi, Shannon and Fisher) of their associated Rakhmanov probability density, are investigated. They quantify the spreading of the polynomials along the orthogonality interval [- 1, 1] in a complementary but different way as the root-mean-square or standard deviation because, contrary to this measure, they do not refer to any specific point of the interval. The explicit expressions of the Fisher length are given. The Renyi lengths are found by the use of the combinatorial multivariable Bell polynomials in terms of the polynomial degree n and the parameters ({alpha}, {beta}). The Shannon length, which cannot be exactly calculated because of its logarithmic functional form, is bounded from below by using sharp upper bounds to general densities on [- 1, +1] given in terms of various expectation values; moreover, its asymptotics is also pointed out. Finally, several computational issues relative to these three quantities are carefully analyzed.

  15. Root exudation and root development of lettuce (Lactuca sativa L. cv. Tizian) as affected by different soils.

    Science.gov (United States)

    Neumann, G; Bott, S; Ohler, M A; Mock, H-P; Lippmann, R; Grosch, R; Smalla, K

    2014-01-01

    Development and activity of plant roots exhibit high adaptive variability. Although it is well-documented, that physicochemical soil properties can strongly influence root morphology and root exudation, particularly under field conditions, a comparative assessment is complicated by the impact of additional factors, such as climate and cropping history. To overcome these limitations, in this study, field soils originating from an unique experimental plot system with three different soil types, which were stored at the same field site for 10 years and exposed to the same agricultural management practice, were used for an investigation on effects of soil type on root development and root exudation. Lettuce (Lactuca sativa L. cv. Tizian) was grown as a model plant under controlled environmental conditions in a minirhizotrone system equipped with root observation windows (rhizoboxes). Root exudates were collected by placing sorption filters onto the root surface followed by subsequent extraction and GC-MS profiling of the trapped compounds. Surprisingly, even in absence of external stress factors with known impact on root exudation, such as pH extremes, water and nutrient limitations/toxicities or soil structure effects (use of sieved soils), root growth characteristics (root length, fine root development) as well as profiles of root exudates were strongly influenced by the soil type used for plant cultivation. The results coincided well with differences in rhizosphere bacterial communities, detected in field-grown lettuce plants cultivated on the same soils (Schreiter et al., this issue). The findings suggest that the observed differences may be the result of plant interactions with the soil-specific microbiomes.

  16. Root exudation and root development of lettuce (Lactuca sativa L.cv. Tizian as affected by different soils

    Directory of Open Access Journals (Sweden)

    Günter eNeumann

    2014-01-01

    Full Text Available Development and activity of plant roots exhibits high adaptive variability. Although it is well-documented, that physicochemical soil properties can strongly influence root morphology and root exudation, particularly under field conditions, a comparative assessment is complicated by the impact of additional factors, such as climate and cropping history. To overcome these limitations, in this study, field soils originating from an unique experimental plot system with three different soil types, which were stored at the same field site for ten years and exposed to the same agricultural management practice, were used for an investigation on effects of soil type on root development and root exudation. Lettuce (Lactuca sativa L. cv. Tizian was used as a model plant, grown under controlled environmental conditions in a minirhizotrone system equipped with root observation windows (rhizoboxes. Root exudates were collected by placing sorption filters onto the root surface followed by subsequent extraction and GC-MS profiling of the trapped compounds. Surprisingly, even in absence of external stress factors with known impact on root exudation, such as pH extremes, water and nutrient limitations/toxicities or soil structure effects (use of sieved soils, root growth characteristics (root length, fine root development as well as profiles of root exudates were strongly influenced by the soil type used for plant cultivation. The results coincided well with differences in rhizosphere bacterial communities, detected in field-grown lettuce plants cultivated on the same soils (Schreiter et al., this issue. The findings suggest that the observed differences may be the result of plant interactions with the soil-specific microbiomes.

  17. Root exudation and root development of lettuce (Lactuca sativa L. cv. Tizian) as affected by different soils

    Science.gov (United States)

    Neumann, G.; Bott, S.; Ohler, M. A.; Mock, H.-P.; Lippmann, R.; Grosch, R.; Smalla, K.

    2014-01-01

    Development and activity of plant roots exhibit high adaptive variability. Although it is well-documented, that physicochemical soil properties can strongly influence root morphology and root exudation, particularly under field conditions, a comparative assessment is complicated by the impact of additional factors, such as climate and cropping history. To overcome these limitations, in this study, field soils originating from an unique experimental plot system with three different soil types, which were stored at the same field site for 10 years and exposed to the same agricultural management practice, were used for an investigation on effects of soil type on root development and root exudation. Lettuce (Lactuca sativa L. cv. Tizian) was grown as a model plant under controlled environmental conditions in a minirhizotrone system equipped with root observation windows (rhizoboxes). Root exudates were collected by placing sorption filters onto the root surface followed by subsequent extraction and GC-MS profiling of the trapped compounds. Surprisingly, even in absence of external stress factors with known impact on root exudation, such as pH extremes, water and nutrient limitations/toxicities or soil structure effects (use of sieved soils), root growth characteristics (root length, fine root development) as well as profiles of root exudates were strongly influenced by the soil type used for plant cultivation. The results coincided well with differences in rhizosphere bacterial communities, detected in field-grown lettuce plants cultivated on the same soils (Schreiter et al., this issue). The findings suggest that the observed differences may be the result of plant interactions with the soil-specific microbiomes. PMID:24478764

  18. Genetic variants associated with the root system architecture of oilseed rape (Brassica napus L.) under contrasting phosphate supply.

    Science.gov (United States)

    Wang, Xiaohua; Chen, Yanling; Thomas, Catherine L; Ding, Guangda; Xu, Ping; Shi, Dexu; Grandke, Fabian; Jin, Kemo; Cai, Hongmei; Xu, Fangsen; Yi, Bin; Broadley, Martin R; Shi, Lei

    2017-08-01

    Breeding crops with ideal root system architecture for efficient absorption of phosphorus is an important strategy to reduce the use of phosphate fertilizers. To investigate genetic variants leading to changes in root system architecture, 405 oilseed rape cultivars were genotyped with a 60K Brassica Infinium SNP array in low and high P environments. A total of 285 single-nucleotide polymorphisms were associated with root system architecture traits at varying phosphorus levels. Nine single-nucleotide polymorphisms corroborate a previous linkage analysis of root system architecture quantitative trait loci in the BnaTNDH population. One peak single-nucleotide polymorphism region on A3 was associated with all root system architecture traits and co-localized with a quantitative trait locus for primary root length at low phosphorus. Two more single-nucleotide polymorphism peaks on A5 for root dry weight at low phosphorus were detected in both growth systems and co-localized with a quantitative trait locus for the same trait. The candidate genes identified on A3 form a haplotype 'BnA3Hap', that will be important for understanding the phosphorus/root system interaction and for the incorporation into Brassica napus breeding programs. © The Author 2017. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

  19. (Lamiaceae) root extracts

    African Journals Online (AJOL)

    Purpose: To evaluate the larvicidal, nematicidal, antifeedant, and antifungal effects of 10 solvent extracts of Mentha spicata root. Methods: Ten solvent extracts were investigated for their total flavonoid and phenolic content and screened for larvicidal, nematicidal, antifeedant, and antifungal activities. The total phenolic ...

  20. Trade-Offs between Drought Survival and Rooting Strategy of Two South American Mediterranean Tree Species: Implications for Dryland Forests Restoration

    Directory of Open Access Journals (Sweden)

    Juan F. Ovalle

    2015-10-01

    Full Text Available Differences in water-acquisition strategies of tree root systems can determine the capacity to survive under severe drought. We evaluate the effects of field water shortage on early survival, growth and root morphological variables of two South American Mediterranean tree species with different rooting strategies during two growing seasons. One year-old Quillaja saponaria (deep-rooted and Cryptocarya alba (shallow-rooted seedlings were established under two watering treatments (2 L·week−1·plant−1 and no water in a complete randomized design. Watering improved the final survival of both species, but the increase was only significantly higher for the shallow-rooted species. The survival rates of deep- and shallow-rooted species was 100% and 71% with watering treatment, and 96% and 10% for the unwatered treatment, respectively. Root morphological variables of deep-rooted species such as surface area, volume, and diameter were higher under unwatered treatment. On the other hand, shallow-rooted species had a higher total root dry mass, length, surface area with watering treatments. Our findings suggest that deep-rooted species are highly recommended for reforestation in dry conditions, even under low soil water availability. Water supplements during the summer season can attenuate the differences between deep- and shallow-rooted species in their ability to survive drought during the early stage.

  1. Experimentally reduced root-microbe interactions reveal limited plasticity in functional root traits in Acer and Quercus.

    Science.gov (United States)

    Lee, Mei-Ho; Comas, Louise H; Callahan, Hilary S

    2014-02-01

    Interactions between roots and soil microbes are critical components of below-ground ecology. It is essential to quantify the magnitude of root trait variation both among and within species, including variation due to plasticity. In addition to contextualizing the magnitude of plasticity relative to differences between species, studies of plasticity can ascertain if plasticity is predictable and whether an environmental factor elicits changes in traits that are functionally advantageous. To compare functional traits and trait plasticities in fine root tissues with natural and reduced levels of colonization by microbial symbionts, trimmed and surface-sterilized root segments of 2-year-old Acer rubrum and Quercus rubra seedlings were manipulated. Segments were then replanted into satellite pots filled with control or heat-treated soil, both originally derived from a natural forest. Mycorrhizal colonization was near zero in roots grown in heat-treated soil; roots grown in control soil matched the higher colonization levels observed in unmanipulated root samples collected from field locations. Between-treatment comparisons revealed negligible plasticity for root diameter, branching intensity and nitrogen concentration across both species. Roots from treated soils had decreased tissue density (approx. 10-20 %) and increased specific root length (approx. 10-30 %). In contrast, species differences were significant and greater than treatment effects in traits other than tissue density. Interspecific trait differences were also significant in field samples, which generally resembled greenhouse samples. The combination of experimental and field approaches was useful for contextualizing trait plasticity in comparison with inter- and intra-specific trait variation. Findings that root traits are largely species dependent, with the exception of root tissue density, are discussed in the context of current literature on root trait variation, interactions with symbionts and recent

  2. Free radical scavenging and total antioxidant capacity of root extracts of Anchomanes difformis Engl. (Araceae).

    Science.gov (United States)

    Aliyu, Abubakar B; Ibrahim, Mohammed A; Musa, Aliyu M; Musa, Aisha O; Kiplimo, Joyce J; Oyewale, Adebayo O

    2013-01-01

    Antioxidants activities from plants sources have attracted a wide range of interest across the world in recent times. This is due to growing concern for safe and alternative sources of antioxidants. The free radical scavenging activity using 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), reducing power assay, total antioxidant capacity of the phosphomolybdenum method and the total phenolics content using the Folin-Ciocalteu reagent were carried out on the acetone, n-butanol and methanol root extracts of Anchomanes difformis. The results of the total phenolics content expressed in mg/100 g of gallic acid equivalent (GAE) showed that the n-butanol extract has significantly (p extracts. All the extracts displayed strong concentration dependent radical scavenging activity. It was also observed that the n-butanol extract showed higher activity of 70.87% and 78.59% at low concentrations of 31.25 microg/mL and 62.5 microg/mL, respectively, than methanol and acetone extracts. The results also showed that the n-butanol extract has strongest reducing ability which is comparable to that of gallic acid at all the concentrations tested. Phytochemical screening on the extracts revealed the presence of flavonoids, saponins, and tannins. The results suggest that n-butanol extract of the plant is very rich in antioxidant compounds worthy of further investigations.

  3. Evaluation of the Root and Canal Morphology of Mandibular Permanent Anterior Teeth in an Iranian Population by Cone-Beam Computed Tomography

    Directory of Open Access Journals (Sweden)

    Mohsen Aminsobhani

    2013-01-01

    Full Text Available Objective: To evaluate differences in the root and canal configurations of mandibular permanent anterior incisors and canines in an Iranian population by means of Cone Beam CT (CBCT images.Materials and Methods: Four hundred CBCT images of mandibular permanent incisors and canines that met the inclusion criteria were evaluated. Vertucci´s classification was used to evaluate the number of roots, number of root canals, root lengths, root curvatures and canal types.Results: Totally 632 central incisors, 614 lateral incisors and 608 canines were evaluated. The average length of the mandibular central, lateral incisors and canines was 21.3±0.10, 21.9± 0.13 and 25.1± 0.11 mm, respectively. All of the mandibular central and lateral incisors had one root, but the incidence of single-rooted mandibular canines and two-rooted mandibular canines was 96.3% and 4.7%, respectively. The majority of mandibular central, lateral incisors and canines had one canal (72.7%, 70.6% and 71.8%, respectively. Five types of Vertucci canal configurations were seen in the evaluated teeth. Type 1 Vertucci configuration was the most prevalent configuration (72.3%, 70.6% and 71.8% for the central, lateral incisors and canines, respectively, and type 5 Vertucci canal configuration was the least prevalent type seen (3.3%, 3.2% and 2.3% for the central, lateral incisors and canines, respectively. The most frequent root curvatures in these teeth were distally and buccally. No significant difference was seen between male and female patients regarding any of the parameters evaluated in this study (p>0.05.Conclusion: More attention should be given to the detection of additional canals and the recognition of canal curvature in Iranian patients.

  4. Management of Root Knot Nematode on Tomato through Grafting Root Stock of Solanum sisymbriifolium

    Directory of Open Access Journals (Sweden)

    Suraj Baidya

    2017-05-01

    Full Text Available The root-knot nematodes (Meloidogyne spp are difficult to manage once established in the field because of their wide host range, and soil-borne nature. Thus, the aim of the present study was to examine the use of resistant root stock of wild brinjal (Solanum sisymbriifolium to reduce the loss caused by the nematodes on tomato. For the management of root-knot nematodes, grafted plant with resistant root stock of the wild brinjal was tested under farmers’ field conditions at Hemza of Kaski district. Grafted and non-grafted plants were produced in root-knot nematode-free soil. Around three week-old grafted and non-grafted tomato plants were transplanted in four different plastic tunnels where root-knot nematodes had been reported previously. The plants were planted in diagonal position to each other as a pair plot in 80 × 60 cm2 spacing in an average of 20 × 7 m2 plastic tunnels. Galling Index (GI was recorded three times in five randomly selected plants in each plot at 60 days intervals. The first observation was recorded two months after transplanting. Total fruit yield was recorded from same plants. In the grafted plants, the root system was totally free from gall whereas in an average of 7.5 GI in 0-10 scale was recorded in the non-grafted plants. Fruits were harvested from time to time and cumulated after final harvest to calculate the total fruit yield. It was estimated that on an average tomato fruit yield was significantly (P>0.05 increased by 37 percent in the grafted plants compared with the non-grafted plants. Grafting technology could be used effectively for cultivation of commonly grown varieties, which are susceptible to root-knot nematodes in disease prone areas. This can be used as an alternative technology for reducing the use of hazardous pesticides for enhancing commercial organic tomato production.

  5. The contribution of fine roots to peatland stability under changing environmental conditions

    Science.gov (United States)

    Malhotra, A.; Brice, D. J.; Childs, J.; Phillips, J.; Hanson, P. J.; Iversen, C. M.

    2017-12-01

    Fine-root production and traits are closely linked with ecosystem nutrient and water fluxes, and may regulate these fluxes in response to environmental change. Plant strategies can shift to favoring below- over aboveground biomass allocation when nutrients or moisture are limited. Fine-roots traits such as root tissue density (RTD) or specific root length (SRL) can also adapt to the environment, for example, by maximizing the area of soil exploited by decreasing RTD and increasing SRL during dry conditions. Fine-root trait plasticity could contribute to the stability of peatland carbon function in response to environmental change. However, the extent and mechanisms of peatland fine-root plasticity are unknown. We investigated fine-root growth and traits and their link to environmental factors and aboveground dynamics at SPRUCE (Spruce and Peatland Responses Under Changing Environments), a warming and elevated CO2 (eCO2) experiment in an ombrotrophic peatland. In the first growing season of whole ecosystem warming, fine-root production increased with warming and drying. Above- versus belowground allocation strategies varied by plant functional type (PFT). In shrubs, contrary to our expectation, aboveground- to fine-root production allocation ratio increased with dryer conditions, perhaps as a response to a concurrent increase in nutrients. Trait response hypotheses were largely supported, with RTD decreasing and SRL increasing with warming; however, response varied among PFTs. Once eCO2 was turned on in the second growing season, preliminary results suggest interactive effects of warming and eCO2 on total fine-root production: production decreased or increased with warming in ambient or elevated CO2 plots, respectively. Both trait and production responses to warming and eCO2 varied by microtopography and depth. Our results highlight plasticity of fine-root traits and biomass allocation strategies; the extent and mechanism of which varies by PFT. We will summarize

  6. Comparison of working length control consistency between hand K-files and Mtwo NiTi rotary system.

    Science.gov (United States)

    Krajczár, Károly; Varga, Enikő; Marada, Gyula; Jeges, Sára; Tóth, Vilmos

    2016-04-01

    The purpose of this study was to investigate the consistency of working length control between hand instrumentation in comparison to engine driven Mtwo nickel-titanium rotary files. Forty extracted maxillary molars were selected and divided onto two parallel groups. The working lengths of the mesiobuccal root canals were estimated. The teeth were fixed in a phantom head. The root canal preparation was carried out group 1 (n=20) with hand K-files, (VDW, Munich, Germany) and group 2 (n=20) with Mtwo instruments (VDW, Munich, Germany). Vestibulo-oral and mesio-distal directional x-ray images were taken before the preparation with #10 K-file, inserted into the mesiobuccal root canal to the working length, and after preparation with #25, #30 and #40 files. Working lenght changes were detected with measurements between the radiological apex and the instrument tips. In the Mtwo group a difference in the working competency (protary files. Mtwo NiTi rotary file did therefore proved to be more accurate in comparison to the conventional hand instrumentation. Working length, Mtwo, nickel-titanium, hand preparation, engine driven preparation.

  7. A Vegetal Biopolymer-Based Biostimulant Promoted Root Growth in Melon While Triggering Brassinosteroids and Stress-Related Compounds

    Directory of Open Access Journals (Sweden)

    Luigi Lucini

    2018-04-01

    Full Text Available Plant biostimulants are receiving great interest for boosting root growth during the first phenological stages of vegetable crops. The present study aimed at elucidating the morphological, physiological, and metabolomic changes occurring in greenhouse melon treated with the biopolymer-based biostimulant Quik-link, containing lateral root promoting peptides, and lignosulphonates. The vegetal-based biopolymer was applied at five rates (0, 0.06, 0.12, 0.24, or 0.48 mL plant-1 as substrate drench. The application of biopolymer-based biostimulant at 0.12 and 0.24 mL plant-1 enhanced dry weight of melon leaves and total biomass by 30.5 and 27.7%, respectively, compared to biopolymer applications at 0.06 mL plant-1 and untreated plants. The root dry biomass, total root length, and surface in biostimulant-treated plants were significantly higher at 0.24 mL plant-1 and to a lesser extent at 0.12 and 0.48 mL plant-1, in comparison to 0.06 mL plant-1 and untreated melon plants. A convoluted biochemical response to the biostimulant treatment was highlighted through UHPLC/QTOF-MS metabolomics, in which brassinosteroids and their interaction with other hormones appeared to play a pivotal role. Root metabolic profile was more markedly altered than leaves, following application of the biopolymer-based biostimulant. Brassinosteroids triggered in roots could have been involved in changes of root development observed after biostimulant application. These hormones, once transported to shoots, could have caused an hormonal imbalance. Indeed, the involvement of abscisic acid, cytokinins, and gibberellin related compounds was observed in leaves following root application of the biopolymer-based biostimulant. Nonetheless, the treatment triggered an accumulation of several metabolites involved in defense mechanisms against biotic and abiotic stresses, such as flavonoids, carotenoids, and glucosinolates, thus potentially improving resistance toward plant stresses.

  8. Influence of leaf number and nodes on the rooting of semiwoody cuttings of flame vine

    Directory of Open Access Journals (Sweden)

    Marília Milani

    2015-12-01

    Full Text Available The flame vine (Pyrostegia venusta (Ker-Gawl. Miers is a semihardwood vine, vigorous, native, native, occurring in all Brazilian biomes and ornamental potential. Technical information about the propagation of this species will contribute to the production of seedlings and with that, their greatest use in landscaping. This study aimed to evaluate the influence of the number of leaves and nodes in rooting intermediate flame vine. The experiment was conducted under conditions of intermittent mist. The experimental design was a randomized block in factorial 2 x 3, being respectively cuttings with one or two nodes, and zero, one or two leaflets. We used four replicates with plots consisting of 12 cuttings placed in substrate of rice hulls in polystyrene trays with 72 cells. We evaluated at 84 days the porcentage of rooted cuttings, length of shoots, dry weight of shoots and, per cutting, average: number of roots - first order; maximum length of each root of the first order, volume and dry weight of roots. It was observed that cuttings with two leaflets enabled 66% of rooting, greater length and dry mass of shoots. The higher quality of the root system occurs with stakes with two leaflets and two nodes. The spread of flame vine is efficient with semi-hardwood cuttings with two nodes and two leaflets, kept in a greenhouse under intermittent mist.

  9. Reinforced aortic root reconstruction for acute type A aortic dissection involving the aortic root

    Directory of Open Access Journals (Sweden)

    Han Qing-qi

    2013-06-01

    Full Text Available OBJECTIVE: There are debates regarding the optimal approach for AAAD involving the aortic root. We described a modified reinforced aortic root reconstruction approach for treating AAAD involving the aortic root. METHODS: A total of 161 patients with AAAD involving the aortic root were treated by our modified reinforced aortic root reconstruction approach from January 1998 to December 2008. Key features of our modified approach were placement of an autologous pericardial patch in the false lumen, lining of the sinotubular junction lumen with a polyester vascular ring, and wrapping of the vessel with Teflon strips. Outcome measures included post-operative mortality, survival, complications, and level of aortic regurgitation. RESULTS: A total of 161 patients were included in the study (mean age: 43.3 1 15.5 years. The mean duration of follow-up was 5.1 1 2.96 years (2-12 years. A total of 10 (6.2% and 11 (6.8% patients died during hospitalization and during follow-up, respectively. Thirty-one (19.3% patients experienced postoperative complications. The 1-, 3-, 5-, and 10-year survival rates were 99.3%, 98%, 93.8%, and 75.5%, respectively. There were no instances of recurrent aortic dissection, aortic aneurysm, or pseudoaneurysm during the entire study period. The severity of aortic regurgitation dramatically decreased immediately after surgery (from 28.6% to 0% grade 3-4 and thereafter slightly increased (from 0% to 7.2% at 5 years and 9.1% at 10 years. CONCLUSION: This modified reinforced aortic root reconstruction was feasible, safe and durable/effective, as indicated by its low mortality, low postoperative complications and high survival rate.

  10. Technical Quality of Root Fillings Performed by Undergraduate Students: A Radiographic Study

    Directory of Open Access Journals (Sweden)

    Tatjana Vukadinov

    2014-01-01

    Full Text Available Aim. The aim of this study was to evaluate the radiographic technical quality of endodontic treatment performed by undergraduate students at the School of Dentistry, Faculty of Medicine, University of Novi Sad, Serbia. Materials and Methods. Electronic records of 220 patients treated by final-year undergraduate students during the school year 2011/2012 were examined, and the final sample consisted of 212 patients, 322 teeth, and 565 root canals. The criteria for overall radiographic adequacy of root canal fillings were defined as the presence of adequate length and density and absence of iatrogenic errors (ledge, fractured instrument, untreated canal, and apical transportation. Chi-square test was used to determine statistical significance between different parameters. Results. Adequate root canal fillings were found in 74.22% of the teeth. The percentage of root fillings with adequate length and density was 89.73% and 92.6%, respectively. Fractured instruments and ledges were present in 16 root canals (2.8%, while the presence of missed canal and apical transportation was observed in 2 cases, each (0.3%. Conclusions. Overall, the technical quality of root canal fillings performed by undergraduate students was satisfactory.

  11. Penetration and post-infection development of root-knot nematodes in watermelon

    Energy Technology Data Exchange (ETDEWEB)

    López-Gómez, M.; Verdejo-Lucas, S.

    2017-07-01

    Meloidogyne javanica has showed less reproductive success than M. incognita in watermelon genotypes. This study was conducted to elucidate the low reproduction of M. javanica in watermelon. The post-infection development of M. javanica in watermelon ‘Sugar Baby’ was determined at progressively higher initial population (Pi) levels at two time points during the life cycle. Plants were inoculated with 0, 25, 50, 100, 200, and 300 second-stage juveniles (J2)/plant. The increase in Pi was correlated with the penetration rates (R2= 0.603, p<0.001) and total numbers of nematodes in the root (R2 =0.963, p< 0.001) but there was no correlation between the Pi and the reproduction factor (eggs/plant/Pi). The population in the roots at 26 days post-inoculation (dpi) consisted primarily of third-stage juveniles (J3) with a small presence of J2 and fourth stages, and egg-laying females. The dominance of the J3, when egg-laying females are expected, point to the malfunction of the feeding sites that failed to support nematode development beyond the J3 stage. The similarities in egg-laying females at 26 and 60 dpi imply the disruption of the life cycle. Watermelon compensated for M. javanica parasitism by increasing vine length (19% to 33%) and dry top weight (40%) in comparison with the non-inoculated plants. The area under the vine length progress curve was significantly larger as the Pi progressively increased (R²=0.417, p<0.001). Physiological variation was detected between the M. incognita populations. M. arenaria had less ability to invade watermelon roots than did M. incognita and M. javanica.

  12. Do shallow soil, low water availability, or their combination increase the competition between grasses with different root systems in karst soil?

    Science.gov (United States)

    Zhao, Yajie; Li, Zhou; Zhang, Jing; Song, Haiyan; Liang, Qianhui; Tao, Jianping; Cornelissen, Johannes H C; Liu, Jinchun

    2017-04-01

    Uneven soil depth and low water availability are the key limiting factors to vegetation restoration and reconstruction in limestone soils such as in vulnerable karst regions. Belowground competition will possibly increase under limited soil resources. Here, we investigate whether low resource availability (including shallow soil, low water availability, and shallow soil and low water availability combined) stimulates the competition between grasses with different root systems in karst soil, by assessing their growth response, biomass allocation, and morphological plasticity. In a full three-way factorial blocked design of soil depth by water availability by neighbor identity, we grew Festuca arundinacea (deep-rooted) and Lolium perenne (shallow-rooted) under normal versus shallow soil depth, high versus low water availability, and in monoculture (conspecific neighbor) versus mixture (neighbor of the other species). The key results were as follows: (1) total biomass and aboveground biomass in either of the species decreased with reduction of resources but were not affected by planting patterns (monoculture or mixture) even at low resource levels. (2) For F. arundinacea, root biomass, root mass fraction, total root length, and root volume were higher in mixture than in monoculture at high resource level (consistent with resource use complementarity), but lower in mixture than in monoculture at low resource levels (consistent with interspecific competition). In contrast for L. perenne, either at high or low resource level, these root traits had mostly similar values at both planting patterns. These results suggest that deep-rooted and shallow-rooted plant species can coexist in karst regions under current climatic regimes. Declining resources, due to shallow soil, a decrease in precipitation, or combined shallow soil and karst drought, increased the root competition between plants of deep-rooted and shallow-rooted species. The root systems of deep-rooted plants may be

  13. A Soil-Plate Based Pipeline for Assessing Cereal Root Growth in Response to Polyethylene Glycol (PEG)-Induced Water Deficit Stress.

    Science.gov (United States)

    Nelson, Sven K; Oliver, Melvin J

    2017-01-01

    Drought is a serious problem that causes losses in crop-yield every year, but the mechanisms underlying how roots respond to water deficit are difficult to study under controlled conditions. Methods for assaying root elongation and architecture, especially for seedlings, are commonly achieved on artificial media, such as agar, moistened filter paper, or in hydroponic systems. However, it has been demonstrated that measuring root characteristics under such conditions does not accurately mimic what is observed when plants are grown in soil. Morphological changes in root behavior occur because of differences in solute diffusion, mechanical impedance, exposure to light (in some designs), and gas exchange of roots grown under these conditions. To address such deficiencies, we developed a quantitative method for assaying seedling root lengths and germination in soil using a plate-based approach with wheat as a model crop. We also further developed the method to include defined water deficits stress levels using the osmotic properties of polyethylene glycol (PEG). Seeds were sown into soil-filled vertical plates and grown in the dark. Root length measurements were collected using digital photography through the transparent lid under green lighting to avoid effects of white light exposure on growth. Photographs were analyzed using the cross-platform ImageJ plugin, SmartRoot, which can detect root edges and partially automate root detection for extraction of lengths. This allowed for quick measurements and straightforward and accurate assessments of non-linear roots. Other measurements, such as root width or angle, can also be collected by this method. An R function was developed to collect exported root length data, process and reformat the data, and output plots depicting root/shoot growth dynamics. For water deficit experiments, seedlings were transplanted side-by-side into well-watered plates and plates containing PEG solutions to simulate precise water deficits.

  14. Seasonal influences on the rooting response of Chir pine (Pinus roxburghii Sarg.

    Directory of Open Access Journals (Sweden)

    S.K. Sharma

    2013-12-01

    Full Text Available Rooting ability of the vegetative cutting depends upon the various factors: age, size, and diameter of cutting, season, rooting substrate and concentration of the applied growth hormone. For assessing the seasonal variation in rooting ability of shoot, cuttings were taken from 4 year old hedges. Shoot cuttings were collected after every two months of hedging spring (March, summer (June, autumn (September and winter (December and treated with 4000 ppm Indole Butyric Acid (IBA, mixed with talc powder and planted in vermiculite filled beds. Suitable control was also maintained, wherein only talc powder was applied to the basal portion of cuttings. Periodical observations were taken on cuttings, with regard to root initiation. The cuttings were uprooted after 12 weeks of planting and observations were recorded. Highly significant differences were observed between root length, shoot length, number of roots per cutting and rooting percentage. This has led to the evaluation of a standard technique for application of mass clonal propagation of Chir pine during summer season (June, which would result into a good success in rooting percentage. This technique could also be helpful in the establishment of germplasm banks of desired genotypes and Clonal Seed Orchards (CSOs. Further, this will also help in overcoming the problem of stock and scion incompatibility, which is commonly faced, when Clonal Seed Orchards are established through grafted material. 

  15. Increased root hair density by loss of WRKY6 in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Markus G. Stetter

    2017-01-01

    Full Text Available Root hairs are unicellular elongations of certain rhizodermal cells that improve the uptake of sparingly soluble and immobile soil nutrients. Among different Arabidopsis thaliana genotypes, root hair density, length and the local acclimation to low inorganic phosphate (Pi differs considerably, when analyzed on split agar plates. Here, genome-wide association fine mapping identified significant single nucleotide polymorphisms associated with the increased root hair density in the absence of local phosphate on chromosome 1. A loss-of-functionmutant of the candidate transcription factor gene WRKY6, which is involved in the acclimation of plants to low phosphorus, had increased root hair density. This is partially explained by a reduced cortical cell diameter in wrky6-3, reducing the rhizodermal cell numbers adjacent to the cortical cells. As a consequence, rhizodermal cells in positions that are in contact with two cortical cells are found more often, leading to higher hair density. Distinct cortical cell diameters and epidermal cell lengths distinguish other Arabidopsis accessions with distinct root hair density and −Pi response from diploid Col-0, while tetraploid Col-0 had generally larger root cell sizes, which explain longer hairs. A distinct radial root morphology within Arabidopsis accessions and wrky6-3explains some, but not all, differences in the root hair acclimation to –Pi.

  16. Effects of gamma irradiation on the shoot length of Cicer seeds

    International Nuclear Information System (INIS)

    Toker, Cengiz; Uzun, Bulent; Canci, Huseyin; Oncu Ceylan, F.

    2005-01-01

    The effects of radiation on the shoot and root lengths of germinated seedling of irradiated seeds of Cicer species, i.e. three kabuli types and four desi types of cultivated chickpea (Cicer arietinum Ladiz.) and 2 annual wild types (C. reticulatum Ladiz. and C. bijugum K.H. Rech.) were investigated. The seeds were irradiated with a 60 Co gamma source using 0, 200, 300 and 400 Gy doses at 1.66 kGy h -1 . At 200 Gy minor effects could be observed, but at 400 Gy an obvious depression of shoot length was observed. The kabuli types were more affected than the desi ones. The critical dose that prevented the shoot and root elongation varied among species and also ranged from genotypes to genotype within species

  17. Total phytosterol content in drug materials and extracts from roots of Acanthospermum hispidum by UV-VIS spectrophotometry

    Directory of Open Access Journals (Sweden)

    Larissa B. D. C. Araújo

    Full Text Available Acanthospermum hispidum DC., Asteraceae, is widely used in folk medicine in Brazil to treat respiratory diseases; this biological property has been attributed to its phytosterol content. This study evaluated the spectrophotometric assay method to quantify the total phytosterol content in raw materials and extracts from roots of A. hispidum. The procedure was based on the quantification at 625 nm after the Liebermann-Burchard reaction. The method was evaluated for linearity, repeatability, intermediate precision, accuracy and robustness. The date indicated that the procedure is a valid analytical tool for materials and herbal derivatives from A. hispidum.

  18. Mechanical touch responses of Arabidopsis TCH1-3 mutant roots on inclined hard-agar surface

    Science.gov (United States)

    Zha, Guodong; Wang, Bochu; Liu, Junyu; Yan, Jie; Zhu, Liqing; Yang, Xingyan

    2016-01-01

    The gravity-induced mechanical touch stimulus can affect plant root architecture. Mechanical touch responses of plant roots are an important aspect of plant root growth and development. Previous studies have reported that Arabidopsis TCH1-3 genes are involved in mechano-related events, how-ever, the physiological functions of TCH1-3 genes in Arabidopsis root mechanoresponses remain unclear. In the present study, we applied an inclined hard agar plate method to produce mechanical touch stimulus, and provided evidence that altered mechanical environment could influence root growth. Furthermore, tch1-3 Arabidopsis mutants were investigated on inclined agar surfaces to explore the functions of TCH1-3 genes on Arabidopsis root mechanoresponses. The results showed that two tch2 mutants, cml24-2 and cml24-4, exhibited significantly reduced root length, biased skewing, and decreased density of lateral root. In addition, primary root length and density of lateral root of tch3 (cml12-2) was significantly decreased on inclined agar surfaces. This study indicates that the tch2 and tch3 mutants are hypersensitive to mechanical touch stimulus, and TCH2 (CML24-2 and CML24-4) and TCH3 (CML12-2) genes may participate in the mechanical touch response of Arabidopsis roots.

  19. Zero-point length from string fluctuations

    International Nuclear Information System (INIS)

    Fontanini, Michele; Spallucci, Euro; Padmanabhan, T.

    2006-01-01

    One of the leading candidates for quantum gravity, viz. string theory, has the following features incorporated in it. (i) The full spacetime is higher-dimensional, with (possibly) compact extra-dimensions; (ii) there is a natural minimal length below which the concept of continuum spacetime needs to be modified by some deeper concept. On the other hand, the existence of a minimal length (zero-point length) in four-dimensional spacetime, with obvious implications as UV regulator, has been often conjectured as a natural aftermath of any correct quantum theory of gravity. We show that one can incorporate the apparently unrelated pieces of information-zero-point length, extra-dimensions, string T-duality-in a consistent framework. This is done in terms of a modified Kaluza-Klein theory that interpolates between (high-energy) string theory and (low-energy) quantum field theory. In this model, the zero-point length in four dimensions is a 'virtual memory' of the length scale of compact extra-dimensions. Such a scale turns out to be determined by T-duality inherited from the underlying fundamental string theory. From a low energy perspective short distance infinities are cutoff by a minimal length which is proportional to the square root of the string slope, i.e., α ' . Thus, we bridge the gap between the string theory domain and the low energy arena of point-particle quantum field theory

  20. [Root canal treatment of mandibular first premolar with 4 root canals: a case report].

    Science.gov (United States)

    Liu, Xin-yang; Zhan, Fu-Liang

    2015-10-01

    The mandibular first premolar can be considered one of the most challenging teeth to treat, due to the complexity of its root canal morphology and increased incidence of multiple canals. A case of endodontic treatment of a mandibular first premolar exhibiting a total of 4 distinct root canals and 4 apical foramina was described. Anatomic variation of root canal morphology should be considered in endodontic treatment to ensure a favorable healing outcome, and its identification could be enhanced by careful examination using a dental operating microscope. Obturation of root canals using a warm vertical compaction technique with a highly-radiopaque root canal sealer, such as AH Plus, after careful ultrasonic activated irrigation might allow the flow of sealer into the narrowed but unprepared part of the canal, thereby facilitating optimum chemo-mechanical debridement of the root canal system.

  1. Incidence of apical root cracks and apical dentinal detachments after canal preparation with hand and rotary files at different instrumentation lengths.

    Science.gov (United States)

    Liu, Rui; Kaiwar, Anjali; Shemesh, Hagay; Wesselink, Paul R; Hou, Benxiang; Wu, Min-Kai

    2013-01-01

    The aim of this study was to compare the incidence of apical root cracks and dentinal detachments after canal preparation with hand and rotary files at different instrumentation lengths. Two hundred forty mandibular incisors were mounted in resin blocks with simulated periodontal ligaments, and the apex was exposed. The root canals were instrumented with rotary and hand files, namely K3, ProTaper, and nickel-titanium Flex K files to the major apical foramen (AF), short AF, or beyond AF. Digital images of the apical surface of every tooth were taken during the apical enlargement at each file change. Development of dentinal defects was determined by comparing these images with the baseline image. Multinomial logistic regression test was performed to identify influencing factors. Apical crack developed in 1 of 80 teeth (1.3%) with hand files and 31 of 160 teeth (19.4%) with rotary files. Apical dentinal detachment developed in 2 of 80 teeth (2.5%) with hand files and 35 of 160 teeth (21.9%) with rotary files. Instrumentation with rotary files terminated 2 mm short of AF and did not cause any cracks. Significantly less cracks and detachments occurred when instrumentation with rotary files was terminated short of AF, as compared with that terminated at or beyond AF (P hand instruments; instrumentation short of AF reduced the risk of dentinal defects. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  2. Total Saponin from Root of Actinidia valvata Dunn Inhibits Hepatoma 22 Growth and Metastasis In Vivo by Suppression Angiogenesis

    Directory of Open Access Journals (Sweden)

    Guo-Yin Zheng

    2012-01-01

    Full Text Available The root of Actinidia valvata dunn has been widely used in the treatment of hepatocellular carcinoma (HCC, proved to be beneficial for a longer and better life in China. In present work, total saponin from root of Actinidia valvata Dunn (TSAVD was extracted, and its effects on hepatoma H22-based mouse in vivo were observed. Primarily transplanted hypodermal hepatoma H22-based mice were used to observe TSAVD effect on tumor growth. The microvessel density (MVD, vascular endothelial growth factor (VEGF, basic fibroblast growth factor (bFGF are characterized factors of angiogenesis, which were compared between TSAVD-treated and control groups. Antimetastasis effect on experimental pulmonary metastasis hepatoma mice was also observed in the study. The results demonstrated that TSAVD can effectively inhibit HCC growth and metastasis in vivo, inhibit the formation of microvessel, downregulate expressions of VEGF and bFGF, and retrain angiogenesis of hepatoma 22 which could be one of the reasons.

  3. Root deformation reduces tolerance of lodgepole pine to attack by Warren root collar weevil.

    Science.gov (United States)

    Robert, Jeanne A; Lindgren, B Staffan

    2010-04-01

    Surveys were conducted on regenerating stands of lodgepole pine to determine the relationship between root deformation and susceptibility to attack by the Warren root collar weevil, Hylobius warreni Wood. The total number of trees attacked by H. warreni did not differ between planted and natural trees. A matched case-control logistic regression suggested that root cross-sectional area was more important in predicting weevil attack for naturally regenerated trees than for planted trees, but weevils were associated with a larger reduction in height-to-diameter ratios for trees with planted root characteristics than for trees with natural root form. Neither the stability of attacked versus unattacked trees differed significantly and there was no significant interaction of weevil attack and tree type, but weevil-killed trees had different root characteristics than alive, attacked trees. Lateral distribution and root cross-sectional area were significant predictors of alive attacked trees versus weevil-killed trees, suggesting that trees with poor lateral spread or poor root cross-sectional area are more likely to die from weevil attack. We conclude that root deformation does not necessarily increase susceptibility to attack but may increase the likelihood of mortality. Thus, measures to facilitate good root form are needed when planting pine in areas with high risk of Warren root collar weevil attack.

  4. The root anchorage ability of Salix alba var. tristis using a pull-out test

    African Journals Online (AJOL)

    user

    2011-11-21

    Nov 21, 2011 ... Full Length Research Paper. The root ... and the University of Natural Resources and applied Life. Sciences ... The design of the apparatus is ..... In The Supporting. Roots of ... Measurements in Geomechanics. Swets and ...

  5. Methods of plant root exudates analysis: a review

    Directory of Open Access Journals (Sweden)

    Peter Dundek

    2011-01-01

    Full Text Available The aim of this review is to summarise current knowledge on methods being used to determine individual compounds and properties of water-soluble plant root exudates. These compounds include amino acids, organic acids and simple sugars, as well as polysaccharides, proteins and organic substances. Qualitative composition of water-soluble root exudates and exudation rate are commonly measured with the aim of consequent synthetic preparation of plant root exudates to be supplied to soil to create artificial rhizosphere for different experimental purposes. Root exudates collection usually requires consequent filtration or centrifugation to remove solids, root detritus and microbial cell debris, and consequent concentration using an evaporator, lyophilizator or ultrafiltration. Methods used for analysis of total groups of compounds (total proteins and total carbohydrates and total organic carbon are simple. On the other hand, HPLC or GS/MS are commonly used to analyse individual low molecular weight organic molecules (sugars, organic acids and amino acids with separation using different columns. Other properties such as pH, conductivity or activity of different enzymes as well as gel electrophoresis of proteins are sometimes assessed. All of these methods are discussed in this work.

  6. Effects of different tillage and transplanting methods on rice rooting ability

    International Nuclear Information System (INIS)

    Ren Wanjun; Yang Wenyu; Fan Gaoqiong; Wu Jinxiu; Wang Lihong

    2007-01-01

    Effects of different tillage and transplanting methods on rice rooting ability were studied with the methods of water culture and 3 H labeling. The results showed that the dynamic curve of rooting ability had single peak during growth period, and the peak of root length per plant, root number and root dry weight appeared at booting. With conventional tillage and transplanting method, the rice plant had the strongest rooting ability, under non-tillage treatment (BCSNT), the rooting ability was the lowest during elongating to heading. After 10d of heading, the dry weight and 3 H specific activity of BCSNT was higher than other treatments, at the same time, the percentage of 3 H assimilate at new root was the highest. Dry weight was positively correlated with percentage of 3 H assimilate of new root, while negatively with percentage of 3 H assimilate of panicle. (authors)

  7. Symbiosis of Arbuscular Mycorrhizal Fungi and Robinia pseudoacacia L. Improves Root Tensile Strength and Soil Aggregate Stability.

    Science.gov (United States)

    Zhang, Haoqiang; Liu, Zhenkun; Chen, Hui; Tang, Ming

    2016-01-01

    Robinia pseudoacacia L. (black locust) is a widely planted tree species on Loess Plateau for revegetation. Due to its symbiosis forming capability with arbuscular mycorrhizal (AM) fungi, we explored the influence of arbuscular mycorrhizal fungi on plant biomass, root morphology, root tensile strength and soil aggregate stability in a pot experiment. We inoculated R. pseudoacacia with/without AM fungus (Rhizophagus irregularis or Glomus versiforme), and measured root colonization, plant growth, root morphological characters, root tensile force and tensile strength, and parameters for soil aggregate stability at twelve weeks after inoculation. AM fungi colonized more than 70% plant root, significantly improved plant growth. Meanwhile, AM fungi elevated root morphological parameters, root tensile force, root tensile strength, Glomalin-related soil protein (GRSP) content in soil, and parameters for soil aggregate stability such as water stable aggregate (WSA), mean weight diameter (MWD) and geometric mean diameter (GMD). Root length was highly correlated with WSA, MWD and GMD, while hyphae length was highly correlated with GRSP content. The improved R. pseudoacacia growth, root tensile strength and soil aggregate stability indicated that AM fungi could accelerate soil fixation and stabilization with R. pseudoacacia, and its function in revegetation on Loess Plateau deserves more attention.

  8. Effect of digital noise reduction on the accuracy of endodontic file length determination

    International Nuclear Information System (INIS)

    Mehdizadeh, Mojdeh; Khademi, Abbas Ali; Shokraneh, Ali; Farhadi, Nastaran

    2013-01-01

    The aim of the present study was to evaluate the measurement accuracy of endodontic file length on periapical digital radiography after application of noise reduction digital enhancement. Thirty-five human single-rooted permanent teeth with canals measuring 20-24 mm in length were selected. ISO no.08 endodontic files were placed in the root canals of the teeth. The file lengths were measured with a digital caliper as the standard value. Standard periapical digital images were obtained using the Digora digital radiographic system and a dental X-ray unit. In order to produce the enhanced images, the noise reduction option was applied. Two blinded radiologists measured the file lengths on the original and enhanced images. The measurements were compared by repeated measures ANOVA and the Bonferroni test (a=0.05). Both the original and enhanced digital images provided significantly longer measurements compared with the standard value (P 0.05). Noise reduction digital enhancement did not influence the measurement accuracy of the length of the thin endodontic files on the digital periapical radiographs despite the fact that noise reduction could result in the elimination of fine details of the images.

  9. Effects of tooth root contact on the stability of orthodontic anchor screws in the maxilla: Comparison between self-drilling and self-tapping methods.

    Science.gov (United States)

    Iwai, Hiroaki; Motoyoshi, Mitsuru; Uchida, Yasuki; Matsuoka, Miho; Shimizu, Noriyoshi

    2015-04-01

    We evaluated the effects of screw placement angle on the frequency of root contact and the effects of root contact on screw stability, comparing self-drilling and self-tapping methods. In total, 80 patients with 142 screws (diameter, 1.6 mm; length, 8.0 mm) were included. Cone-beam computed tomography images were taken. Cortical bone thickness, interroot distance, shortest distance between the screw and adjacent tooth root, and screw placement angle were measured. The success rates of the screws were 91.5% for the self-drilling method and 94.4% for the self-tapping method (P >0.05). The self-drilling screws tended to contact the distal tooth roots in the right maxilla. In the self-drilling method, the failure rate was significantly higher in the root contact group than in the no-contact group (P tapping methods in the maxilla. Avoidance of tooth root contact may improve the success rate more in the self-drilling method than in the self-tapping method. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  10. Root canal morphology of primary molars: a micro-computed tomography study.

    Science.gov (United States)

    Fumes, A C; Sousa-Neto, M D; Leoni, G B; Versiani, M A; da Silva, L A B; da Silva, R A B; Consolaro, A

    2014-10-01

    This was to investigate the root canal morphology of primary molar teeth using micro-computed tomography. Primary maxillary (n = 20) and mandibular (n = 20) molars were scanned at a resolution of 16.7 μm and analysed regarding the number, location, volume, area, structured model index (SMI), area, roundness, diameters, and length of canals, as well as the thickness of dentine in the apical third. Data were statistically compared by using paired-sample t test, independent sample t test, and one-way analysis of variance with significance level set as 5%. Overall, no statistical differences were found between the canals with respect to length, SMI, dentine thickness, area, roundness, and diameter (p > 0.05). A double canal system was observed in the mesial and mesio-buccal roots of the mandibular and maxillary molars, respectively. The thickness in the internal aspect of the roots was lower than in the external aspect. Cross-sectional evaluation of the roots in the apical third showed flat-shaped canals in the mandibular molars and ribbon- and oval-shaped canals in the maxillary molars. External and internal anatomy of the primary first molars closely resemble the primary second molars. The reported data may help clinicians to obtain a thorough understanding of the morphological variations of root canals in primary molars to overcome problems related to shaping and cleaning procedures, allowing appropriate management strategies for root canal treatment.

  11. Complementarity in nutrient foraging strategies of absorptive fine roots and arbuscular mycorrhizal fungi across 14 coexisting subtropical tree species.

    Science.gov (United States)

    Liu, Bitao; Li, Hongbo; Zhu, Biao; Koide, Roger T; Eissenstat, David M; Guo, Dali

    2015-10-01

    In most cases, both roots and mycorrhizal fungi are needed for plant nutrient foraging. Frequently, the colonization of roots by arbuscular mycorrhizal (AM) fungi seems to be greater in species with thick and sparsely branched roots than in species with thin and densely branched roots. Yet, whether a complementarity exists between roots and mycorrhizal fungi across these two types of root system remains unclear. We measured traits related to nutrient foraging (root morphology, architecture and proliferation, AM colonization and extramatrical hyphal length) across 14 coexisting AM subtropical tree species following root pruning and nutrient addition treatments. After root pruning, species with thinner roots showed more root growth, but lower mycorrhizal colonization, than species with thicker roots. Under multi-nutrient (NPK) addition, root growth increased, but mycorrhizal colonization decreased significantly, whereas no significant changes were found under nitrogen or phosphate additions. Moreover, root length proliferation was mainly achieved by altering root architecture, but not root morphology. Thin-root species seem to forage nutrients mainly via roots, whereas thick-root species rely more on mycorrhizal fungi. In addition, the reliance on mycorrhizal fungi was reduced by nutrient additions across all species. These findings highlight complementary strategies for nutrient foraging across coexisting species with contrasting root traits. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  12. Effect of Piriformospora indica inoculation on root development and distribution of maize (Zea mays L.) in the presence of petroleum contaminated soil

    Science.gov (United States)

    Zamani, Javad; Hajabbasi, Mohammad Ali; Alaie, Ebrahim

    2014-05-01

    The root systems of most terrestrial plants are confronted to various abiotic and biotic stresses. One of these abiotic stresses is contamination of soil with petroleum hydrocarbon, which the efficiency of phytoremediation of petroleum hydrocarbons in soils is dependent on the ability of plant roots to development into the contaminated soils. Piriformospora indica represents a recently discovered fungus that transfers considerable beneficial impact to its host plants. A rhizotron experiment was conducted to study the effects of P. Indica inoculation on root distribution and root and shoot development of maize (Zea mays L.) in the presence of three patterns of petroleum contamination in the soil (subsurface contamination, continuous contamination and without contamination (control)). Root distribution and root and shoot development were monitored over time. The final root and shoot biomass and the final TPH concentration in the rhizosphere were determined. Analysis of digitized images which were prepared of the tracing of the appeared roots along the front rhizotrons showed the depth and total length of root network in the contamination treatments were significantly decreased. Although the degradation of TPH in the rhizosphere of maize was significant, but there were no significant differences between degradation of TPH in the rhizosphere of +P. indica plants in comparison to -P. indica plants.

  13. Prioritizing quantitative trait loci for root system architecture in tetraploid wheat.

    Science.gov (United States)

    Maccaferri, Marco; El-Feki, Walid; Nazemi, Ghasemali; Salvi, Silvio; Canè, Maria Angela; Colalongo, Maria Chiara; Stefanelli, Sandra; Tuberosa, Roberto

    2016-02-01

    Optimization of root system architecture (RSA) traits is an important objective for modern wheat breeding. Linkage and association mapping for RSA in two recombinant inbred line populations and one association mapping panel of 183 elite durum wheat (Triticum turgidum L. var. durum Desf.) accessions evaluated as seedlings grown on filter paper/polycarbonate screening plates revealed 20 clusters of quantitative trait loci (QTLs) for root length and number, as well as 30 QTLs for root growth angle (RGA). Divergent RGA phenotypes observed by seminal root screening were validated by root phenotyping of field-grown adult plants. QTLs were mapped on a high-density tetraploid consensus map based on transcript-associated Illumina 90K single nucleotide polymorphisms (SNPs) developed for bread and durum wheat, thus allowing for an accurate cross-referencing of RSA QTLs between durum and bread wheat. Among the main QTL clusters for root length and number highlighted in this study, 15 overlapped with QTLs for multiple RSA traits reported in bread wheat, while out of 30 QTLs for RGA, only six showed co-location with previously reported QTLs in wheat. Based on their relative additive effects/significance, allelic distribution in the association mapping panel, and co-location with QTLs for grain weight and grain yield, the RSA QTLs have been prioritized in terms of breeding value. Three major QTL clusters for root length and number (RSA_QTL_cluster_5#, RSA_QTL_cluster_6#, and RSA_QTL_cluster_12#) and nine RGA QTL clusters (QRGA.ubo-2A.1, QRGA.ubo-2A.3, QRGA.ubo-2B.2/2B.3, QRGA.ubo-4B.4, QRGA.ubo-6A.1, QRGA.ubo-6A.2, QRGA.ubo-7A.1, QRGA.ubo-7A.2, and QRGA.ubo-7B) appear particularly valuable for further characterization towards a possible implementation of breeding applications in marker-assisted selection and/or cloning of the causal genes underlying the QTLs. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  14. Quark ensembles with infinite correlation length

    OpenAIRE

    Molodtsov, S. V.; Zinovjev, G. M.

    2014-01-01

    By studying quark ensembles with infinite correlation length we formulate the quantum field theory model that, as we show, is exactly integrable and develops an instability of its standard vacuum ensemble (the Dirac sea). We argue such an instability is rooted in high ground state degeneracy (for 'realistic' space-time dimensions) featuring a fairly specific form of energy distribution, and with the cutoff parameter going to infinity this inherent energy distribution becomes infinitely narrow...

  15. An evaluation of inexpensive methods for root image acquisition when using rhizotrons.

    Science.gov (United States)

    Mohamed, Awaz; Monnier, Yogan; Mao, Zhun; Lobet, Guillaume; Maeght, Jean-Luc; Ramel, Merlin; Stokes, Alexia

    2017-01-01

    Belowground processes play an essential role in ecosystem nutrient cycling and the global carbon budget cycle. Quantifying fine root growth is crucial to the understanding of ecosystem structure and function and in predicting how ecosystems respond to climate variability. A better understanding of root system growth is necessary, but choosing the best method of observation is complex, especially in the natural soil environment. Here, we compare five methods of root image acquisition using inexpensive technology that is currently available on the market: flatbed scanner, handheld scanner, manual tracing, a smartphone application scanner and a time-lapse camera. Using the five methods, root elongation rate (RER) was measured for three months, on roots of hybrid walnut ( Juglans nigra  ×  Juglans regia L.) in rhizotrons installed in agroforests. When all methods were compared together, there were no significant differences in relative cumulative root length. However, the time-lapse camera and the manual tracing method significantly overestimated the relative mean diameter of roots compared to the three scanning methods. The smartphone scanning application was found to perform best overall when considering image quality and ease of use in the field. The automatic time-lapse camera was useful for measuring RER over several months without any human intervention. Our results show that inexpensive scanning and automated methods provide correct measurements of root elongation and length (but not diameter when using the time-lapse camera). These methods are capable of detecting fine roots to a diameter of 0.1 mm and can therefore be selected by the user depending on the data required.

  16. Determination of total As in onion plants growing in contaminated substrates by total reflection X-ray fluorescence

    International Nuclear Information System (INIS)

    Lue-Meru Marco Parra

    2011-01-01

    The onion (Allium cepa L.) is one of the most important cultivars in the world and its production level occupies the second place in Venezuela. It becomes important to develop analytical procedures for arsenic determination and to study the effect of this element on the cultures, as well the absorption, transport and translocation processes. A TXRF method for As determination in onions was developed. Two treatments were applied to the onion plants, As contaminated and control. The contaminant was added to the plants to an amount of 100 μg, in a single time 3 weeks after the transplant of plantlets. The green leaves bulbs, and roots together with the stems were separated 45 days after transplant and analyzed by TXRF and HG-AAS for total Arsenic determination. A good agreement was found between these two techniques, demonstrating the accuracy of the TXRF procedure. It was found that the highest concentration corresponded to the root and stems (37 ± 31 μg g -1 ), followed by the bulbs (11 ± 7 μg g -1 ), being the smallest level found in the green leaves (4 ± 3 μg g -1 ). At low As contamination levels of 0.25 μg g -1 , a risk for translocation of the toxic element to the edible parts of the onion plants exists. At this level the normal development of the plant is not affected, being the only exception the root length, which is significantly higher in the contaminated treatment. (author)

  17. A paradox resolved: Sulfide acquisition by roots of seep tubeworms sustains net chemoautotrophy

    Science.gov (United States)

    Freytag, John K.; Girguis, Peter R.; Bergquist, Derk C.; Andras, Jason P.; Childress, James J.; Fisher, Charles R.

    2001-01-01

    Vestimentiferan tubeworms, symbiotic with sulfur-oxidizing chemoautotrophic bacteria, dominate many cold-seep sites in the Gulf of Mexico. The most abundant vestimentiferan species at these sites, Lamellibrachia cf. luymesi, grows quite slowly to lengths exceeding 2 meters and lives in excess of 170–250 years. L. cf. luymesi can grow a posterior extension of its tube and tissue, termed a “root,” down into sulfidic sediments below its point of original attachment. This extension can be longer than the anterior portion of the animal. Here we show, using methods optimized for detection of hydrogen sulfide down to 0.1 μM in seawater, that hydrogen sulfide was never detected around the plumes of large cold-seep vestimentiferans and rarely detectable only around the bases of mature aggregations. Respiration experiments, which exposed the root portions of L. cf. luymesi to sulfide concentrations between 51–561 μM, demonstrate that L. cf. luymesi use their roots as a respiratory surface to acquire sulfide at an average rate of 4.1 μmol⋅g−1⋅h−1. Net dissolved inorganic carbon uptake across the plume of the tubeworms was shown to occur in response to exposure of the posterior (root) portion of the worms to sulfide, demonstrating that sulfide acquisition by roots of the seep vestimentiferan L. cf. luymesi can be sufficient to fuel net autotrophic total dissolved inorganic carbon uptake. PMID:11687647

  18. Toxicity of arsenic (III) and (V) on plant growth, element uptake, and total amylolytic activity of mesquite (Prosopis juliflora x P. velutina).

    Science.gov (United States)

    Mokgalaka-Matlala, Ntebogeng S; Flores-Tavizón, Edith; Castillo-Michel, Hiram; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

    2008-01-01

    The effects of arsenite [As(III)] and arsenate [As(V)] on the growth of roots, stems, and leaves and the uptake of arsenic (As), micro- and macronutrients, and total amylolytic activity were investigated to elucidate the phytotoxicity of As to the mesquite plant (Prosopis juliflora x P. velutina). The plant growth was evaluated by measuring the root and shoot length, and the element uptake was determined using inductively coupled plasma optical emission spectroscopy. The root and leaf elongation decreased significantly with increasing As(III) and As(V) concentrations; whereas, stem elongation remained unchanged. The As uptake increased with increasing As(III) or As(V) concentrations in the medium. Plants treated with 50 mg/L As(III) accumulated up to 920 mg/kg dry weight (d wt) in roots and 522 mg/kg d wt in leaves, while plants exposed to 50 mg/L As(V) accumulated 1980 and 210 mg/kg d wt in roots and leaves, respectively. Increasing the As(V) concentration up to 20 mg/L resulted in a decrease in the total amylolytic activity. On the contrary, total amylolytic activity in As(III)-treated plants increased with increasing As concentration up to 20 mg/L. The macro- and micronutrient concentrations changed in As-treated plants. In shoots, Mo and K were reduced but Ca was increased, while in roots Fe and Ca were increased but K was reduced. These changes reduced the size of the plants, mainly in the As(III)-treated plants; however, there were no visible sign of As toxicity.

  19. Prevalence and morphometric analysis of three-rooted mandibular first molars in a Brazilian subpopulation

    Science.gov (United States)

    Rodrigues, Clarissa Teles; de Oliveira-Santos, Christiano; Bernardineli, Norberti; Duarte, Marco Antonio Hungaro; Bramante, Clovis Monteiro; Minotti-Bonfante, Paloma Gagliardi; Ordinola-Zapata, Ronald

    2016-01-01

    ABSTRACT The knowledge of the internal anatomy of three-rooted mandibular molars may help clinicians to diagnose and plan the root canal treatment in order to provide adequate therapy when this variation is present. Objectives: To determine the prevalence of three-rooted mandibular molars in a Brazilian population using cone beam computed tomography (CBCT) and to analyze the anatomy of mandibular first molars with three roots through micro-CT. Material and Methods: CBCT images of 116 patients were reviewed to determine the prevalence of three-rooted first mandibular molars in a Brazilian subpopulation. Furthermore, with the use of micro-CT, 55 extracted three-rooted mandibular first molars were scanned and reconstructed to assess root length, distance between canal orifices, apical diameter, Vertucci's classification, presence of apical delta, number of foramina and furcations, lateral and accessory canals. The distance between the orifice on the pulp chamber floor and the beginning of the curvature and the angle of canal curvature were analyzed in the distolingual root. Data were compared using the Kruskal-Wallis test (α=0.05). Results: The prevalence of three-rooted mandibular first molars was of 2.58%. Mesial roots showed complex distribution of the root canal system in comparison to the distal roots. The median of major diameters of mesiobuccal, mesiolingual and single mesial canals were: 0.34, 0.41 and 0.60 mm, respectively. The higher values of major diameters were found in the distobuccal canals (0.56 mm) and the lower diameters in the distolingual canals (0.29 mm). The lowest orifice distance was found between the mesial canals (MB-ML) and the highest distance between the distal root canals (DB-DL). Almost all distal roots had one root canal and one apical foramen with few accessory canals. Conclusions: Distolingual root generally has short length, severe curvature and a single root canal with low apical diameter. PMID:27812625

  20. Total direct cost, length of hospital stay, institutional discharges and their determinants from rehabilitation settings in stroke patients.

    Science.gov (United States)

    Saxena, S K; Ng, T P; Yong, D; Fong, N P; Gerald, K

    2006-11-01

    Length of hospital stay (LOHS) is the largest determinant of direct cost for stroke care. Institutional discharges (acute care and nursing homes) from rehabilitation settings add to the direct cost. It is important to identify potentially preventable medical and non-medical reasons determining LOHS and institutional discharges to reduce the direct cost of stroke care. The aim of the study was to ascertain the total direct cost, LOHS, frequency of institutional discharges and their determinants from rehabilitation settings. Observational study was conducted on 200 stroke patients in two rehabilitation settings. The patients were examined for various socio-demographic, neurological and clinical variables upon admission to the rehabilitation hospitals. Information on total direct cost and medical complications during hospitalization were also recorded. The outcome variables measured were total direct cost, LOHS and discharges to institutions (acute care and nursing home facility) and their determinants. The mean and median LOHS in our study were 34 days (SD = 18) and 32 days respectively. LOHS and the cost of hospital stay were significantly correlated. The significant variables associated with LOHS on multiple linear regression analysis were: (i) severe functional impairment/functional dependence Barthel Index institutional discharges (22 to acute care and 17 to nursing homes). On multivariate analysis the significant predictors of discharges to institutions from rehabilitation hospitals were medical complications (OR = 4.37; 95% CI 1.01-12.53) and severe functional impairment/functional dependence. (OR = 5.90, 95% CI 2.32-14.98). Length of hospital stay and discharges to institutions from rehabilitation settings are significantly determined by medical complications. Importance of adhering to clinical pathway/protocol for stroke care is further discussed.

  1. Micro-CT evaluation of root and canal morphology of mandibular first premolars with radicular grooves

    Energy Technology Data Exchange (ETDEWEB)

    Boschetti, Emanuele; Mazzi-Chaves, Jardel Francisco; Versiani, Marco Aurélio; Pécora, Jesus Djalma; Saquy, Paulo Cesar; Sousa Neto, Manoel Damião de, E-mail: sousanet@forp.usp.br [Universidade de São Paulo (USP), Ribeirao Preto, SP (Brazil). Departamento de Odontologia Restauradora; Silva-Sousa, Yara Terezinha Correa; Leoni, Graziela Bianchi [Universidade de Ribeirão Preto (UNAERP), Ribeirão Preto, SP (Brazil). Departmento de Endodontia

    2017-09-15

    The aim of this study was to evaluate morphological features of 70 single-rooted mandibular first premolars with radicular grooves (RG) using micro-CT technology. Teeth were scanned and evaluated regarding the morphology of the roots and root canals as well as length, depth and percentage frequency location of the RG. Volume, surface area and Structure Model Index (SMI) of the canals were measured for the full root length. Two-dimensional parameters and frequency of canal orifices were evaluated at 1, 2, and 3 mm levels from the apical foramen. The number of accessory canals, the dentin thickness, and cross-sectional appearance of the canal at different root levels were also recorded. Expression of deep grooves was observed in 21.42% of the sample. Mean lengths of root and RG were 13.43 mm and 8.5 mm, respectively, while depth of the RG ranged from 0.75 to 1.13 mm. Mean canal volume, surface area and SMI were 10.78 mm{sup 3}, 58.51 mm{sup 2}, and 2.84, respectively. Apical delta was present in 4.35% of the sample and accessory canals were observed mostly at the middle and apical thirds. Two-dimensional parameters indicated an oval-shaped cross-sectional appearance of the root canal with a high percentage frequency of canal divisions (87.15%). Canal configuration type V (58.57%) was the most prevalent. C-shaped configuration was observed in 13 premolars (18.57%), whereas dentin thickness ranged from 1.0 to 1.31 mm. Radicular grooves in mandibular first premolars was associated with the occurrence of several anatomical complexities, including C-shaped canals and divisions of the main root canal. (author)

  2. Micro-CT evaluation of root and canal morphology of mandibular first premolars with radicular grooves

    International Nuclear Information System (INIS)

    Boschetti, Emanuele; Mazzi-Chaves, Jardel Francisco; Versiani, Marco Aurélio; Pécora, Jesus Djalma; Saquy, Paulo Cesar; Sousa Neto, Manoel Damião de; Silva-Sousa, Yara Terezinha Correa; Leoni, Graziela Bianchi

    2017-01-01

    The aim of this study was to evaluate morphological features of 70 single-rooted mandibular first premolars with radicular grooves (RG) using micro-CT technology. Teeth were scanned and evaluated regarding the morphology of the roots and root canals as well as length, depth and percentage frequency location of the RG. Volume, surface area and Structure Model Index (SMI) of the canals were measured for the full root length. Two-dimensional parameters and frequency of canal orifices were evaluated at 1, 2, and 3 mm levels from the apical foramen. The number of accessory canals, the dentin thickness, and cross-sectional appearance of the canal at different root levels were also recorded. Expression of deep grooves was observed in 21.42% of the sample. Mean lengths of root and RG were 13.43 mm and 8.5 mm, respectively, while depth of the RG ranged from 0.75 to 1.13 mm. Mean canal volume, surface area and SMI were 10.78 mm 3 , 58.51 mm 2 , and 2.84, respectively. Apical delta was present in 4.35% of the sample and accessory canals were observed mostly at the middle and apical thirds. Two-dimensional parameters indicated an oval-shaped cross-sectional appearance of the root canal with a high percentage frequency of canal divisions (87.15%). Canal configuration type V (58.57%) was the most prevalent. C-shaped configuration was observed in 13 premolars (18.57%), whereas dentin thickness ranged from 1.0 to 1.31 mm. Radicular grooves in mandibular first premolars was associated with the occurrence of several anatomical complexities, including C-shaped canals and divisions of the main root canal. (author)

  3. Root canal treatment of mandibular second premolar tooth with taurodontism

    Directory of Open Access Journals (Sweden)

    Vujašković Mirjana

    2008-01-01

    Full Text Available INTRODUCTION Taurodontism is a morphoanatomical change in the shape of a tooth. An enlarged body of a tooth with smaller than usual roots is a characteristic feature. Internal tooth anatomy correlates with this appearance, which means that a taurodontal tooth has a large pulp chamber and apically positioned furcations. This dental anomaly may be associated with different syndromes and congenital discoders. CASE OUTLINE The case report presents the patient of a rare case of taurodontism in the mandibular second premolar with chronic periodontitis. Endodontic treatment was performed after dental history and clinical examination. Special care is required in all segments of endodontic treatment of a taurodontal tooth from the identification orifice, canal exploration, determining working length, cleaning and shaping and obturation of the root canal. Precurved K-file was used for canal exploration and location of the furcation. One mesial and one distal canal with the buccal position were identified in the apical third of the root canal. The working lengths of two canals were determined by radiographic interpretation with two K-files in each canal and verified with the apex locator. During canal instrumentation, the third canal was located in the disto-lingual position. The working length of the third canal was established using the apex locator. CONCLUSION Thorough knowledge of tooth anatomy and its variations can lead to lower percentage of endodontic failure. Each clinical case involving these teeth should be investigated carefully, clinically and radiographically to detect additional root canals. High quality radiographs from different angles and proper instrumentarium improve the quality of endodontic procedure.

  4. Adsorption and absorption of polycyclic aromatic hydrocarbons to rice roots

    International Nuclear Information System (INIS)

    Jiao, X.C.; Xu, F.L.; Dawson, R.; Chen, S.H.; Tao, S.

    2007-01-01

    Rice roots and surrounding air, soil and water samples were collected for polycyclic aromatic hydrocarbon (PAH) analysis. The rice roots were separated into lateral roots and nodal roots, and the PAH concentration in the former was found to be higher than that in the latter. In addition, root physiological characteristics including root biotic mass, root lipid content and specific surface area are also discussed. When normalizing the total, adsorption and absorption PAH fractions on a dry root weight basis to root biomass, root lipid, and surface area bases respectively, the differences between PAHs in the two types of roots diminished by 2 to 3 times on average. Results from sequential extraction indicated that PAHs were more easily absorbed by interior rice roots than adsorbed on the surface. In addition, more than 60% of total PAHs accumulated in root tissue for both lateral and nodal roots. However, the results were highly related to the solvent used, extraction time and methodology. Correlation analysis between bioconcentration factors (root over environment) and K OA , K OW showed water to be more significant for PAH adsorption in rice roots than other environmental media. - A sequential extraction method was applied to divide the PAHs accumulated on rice roots into PAHs in root exudates, PAHs adsorbed on root surfaces, and PAHs absorbed in root tissue

  5. Plant root and shoot dynamics during subsurface obstacle interaction

    Science.gov (United States)

    Conn, Nathaniel; Aguilar, Jeffrey; Benfey, Philip; Goldman, Daniel

    As roots grow, they must navigate complex underground environments to anchor and retrieve water and nutrients. From gravity sensing at the root tip to pressure sensing along the tip and elongation zone, the complex mechanosensory feedback system of the root allows it to bend towards greater depths and avoid obstacles of high impedance by asymmetrically suppressing cell elongation. Here we investigate the mechanical and physiological responses of roots to rigid obstacles. We grow Maize, Zea mays, plants in quasi-2D glass containers (22cm x 17cm x 1.4cm) filled with photoelastic gel and observe that, regardless of obstacle interaction, smaller roots branch off the primary root when the upward growing shoot (which contains the first leaf) reaches an average length of 40 mm, coinciding with when the first leaf emerges. However, prior to branching, contacts with obstacles result in reduced root growth rates. The growth rate of the root relative to the shoot is sensitive to the angle of the obstacle surface, whereby the relative root growth is greatest for horizontally oriented surfaces. We posit that root growth is prioritized when horizontal obstacles are encountered to ensure anchoring and access to nutrients during later stages of development. NSF Physics of Living Systems.

  6. Involvement of alternative oxidase (AOX) in adventitious rooting of Olea europaea L. microshoots is linked to adaptive phenylpropanoid and lignin metabolism.

    Science.gov (United States)

    Santos Macedo, E; Sircar, D; Cardoso, H G; Peixe, A; Arnholdt-Schmitt, B

    2012-09-01

    Alternative oxidase (AOX) has been proposed as a functional marker candidate in a number of events involving cell differentiation, including rooting efficiency in semi-hardwood shoot cuttings of olive (Olea europaea L.). To ascertain the general importance of AOX in olive rooting, the auxin-induced rooting process was studied in an in vitro system for microshoot propagation. Inhibition of AOX by salicylhydroxamic acid (SHAM) significantly reduced rooting efficiency. However, the inhibitor failed to exhibit any effect on the preceding calli stage. This makes the system appropriate for distinguishing dedifferentiation and de novo differentiation during root induction. Metabolite analyses of microshoots showed that total phenolics, total flavonoids and lignin contents were significantly reduced upon SHAM treatment. It was concluded that the influence of alternative respiration on root formation was associated to adaptive phenylpropanoid and lignin metabolism. Transcript profiles of two olive AOX genes (OeAOX1a and OeAOX2) were examined during the process of auxin-induced root induction. Both genes displayed stable transcript accumulation in semi-quantitative RT-PCR analysis during all experimental stages. In contrary, when the reverse primer for OeAOX2 was designed from the 3'-UTR instead of the ORF, differential transcript accumulation was observed suggesting posttranscriptional regulation of OeAOX2 during metabolic acclimation. This result confirms former observations in olive semi-hardwood shoot cuttings on differential OeAOX2 expression during root induction. It further points to the importance of future studies on the functional role of sequence and length polymorphisms in the 3'-UTR of this gene. The manuscript reports the general importance of AOX in olive adventitious rooting and the association of alternative respiration to adaptive phenylpropanoid and lignin metabolism.

  7. Biochemical changes in barberries during adventitious root formation: the role of indole-3-butyric acid and hydrogen peroxide

    Directory of Open Access Journals (Sweden)

    Ali Tehranifar

    2014-03-01

    Full Text Available Peroxidase, polyphenol oxidase (PPO, phenolic compounds and total sugars (TS were investigated during root formation in cuttings of Berberis vulgaris var. asperma (BVA and Berberis thunbergii var. atropurpurea (BTA treated with indole-3-butyric acid (IBA and IBA+H2O2. Rooting was observed on BTA cuttings but not on BVA cuttings. The BTA cuttings treated with IBA and IBA+H2O2 showed higher rooting percentages, number of roots, and root length over the control. Those treated with IBA+H2O2 recorded the lowest peroxidase activity after planting. BTA cuttings treated with IBA+H2O2 showed the highest peroxidase activity at 50 d after planting; BVA cuttings under different treatments showed no significant difference for peroxidase activity at planting time or up to 80 d after planting. PPO activity for the BTA cuttings in the control treatment was lower than for other treatments during root formation. The cuttings in the IBA and IBA+H2O2 treatments showed increased PPO activity from 0 to 50 d after planting and a slight decrease in PPO activity from 60 to 80 d after planting. PPO activity for the BVA cuttings was significantly lower than for BTA during root formation. The BTA cuttings treated with IBA and IBA+H2O2 showed the highest phenolic compound content during root formation. The BVA cuttings displayed higher TS than BTA during the initial stage of root formation. A comparison of the anatomical structure of easy-to-root and difficult-to-root cuttings indicated that physical inhibitors did not affect the rooting capacity of BVA.

  8. Soil sheaths, photosynthate distribution to roots, and rhizosphere water relations for Opuntia ficus-indica

    Energy Technology Data Exchange (ETDEWEB)

    Huang, B.; North, G.B.; Nobel, P.S. (Univ. of California, Los Angeles, CA (United States))

    1993-09-01

    Soil sheaths incorporating aggregated soil particles surround young roots of many species, but the effects of such sheaths on water movement between roots and the soil are largely unknown. The quantity and location of root exudates associated with soil sheath along the entire length of its young roots, except within 1.4 cm of the tip. The soil sheaths, which average 0.7 mm in thickness, were composed of soil particles and root hairs, both of which were covered with exuded mucilaginous material. As determined with a [sup 14]C pulse-labeling technique, 2% of newly fixed [sup 14]C-photosynthate was translocated into the roots at 3d, 6% at 9 d, and 8% at 15 d after labeling. The fraction of insoluble [sup 14]C in the roots increased twofold from 3 d to 15 d. Over the same time period, 6%-9% of the [sup 14]C translocated to the roots was exuded into the soil. The soluble [sup 14]C compounds exuded into the soil were greater in the 3-cm segment at the root tip than elsewhere along the root, whereas mucilage was exuded relatively uniformly along roots 15 cm in length. The volumetric efflux of water increase for both sheathed and unsheathed roots as the soil water potential decreased form -0.1 MPa to -1.0 MPa. The efflux rate was greater for unsheathed roots than for sheathed roots, which were more turgid and had a higher water potential, especially at lower soil water potentials. During drying, soil particles in the sheaths aggregate more tightly, making the sheaths less permeable to water and possibly creating air gaps. The soil sheaths of O. ficus-indica thus reduce water loss from the roots to a drying soil. 34 refs., 6 figs., 1 tab.

  9. Variability of root traits in common bean genotypes at different levels of phosphorus supply and ontogenetic stages

    Directory of Open Access Journals (Sweden)

    Roberto dos Santos Trindade

    2014-08-01

    Full Text Available Selection of common bean (Phaseolus vulgaris L. cultivars with enhanced root growth would be a strategy for increasing P uptake and grain yield in tropical soils, but the strong plasticity of root traits may compromise their inclusion in breeding programs. The aim of this study was to evaluate the magnitude of the genotypic variability of root traits in common bean plants at two ontogenetic stages and two soil P levels. Twenty-four common bean genotypes, comprising the four growth habits that exist in the species and two wild genotypes, were grown in 4 kg pots at two levels of applied P (20 and 80 mg kg-1 and harvested at the stages of pod setting and early pod filling. Root area and root length were measured by digital image analysis. Significant genotype × P level and genotype × harvest interactions in analysis of variance indicate that the genotypic variation of root traits depended on soil nutrient availability and the stage at which evaluation was made. Genotypes differed for taproot mass, basal and lateral root mass, root area and root length at both P levels and growth stages; differences in specific root area and length were small. Genotypes with growth habits II (upright indeterminate and III (prostrate indeterminate showed better adaptation to limited P supply than genotypes of groups I (determinate and IV (indeterminate climbing. Between the two harvests, genotypes of groups II and III increased the mass of basal and lateral roots by 40 and 50 %, respectively, whereas genotypes of groups I and IV by only 7 and 19 %. Values of the genotypic coefficient of determination, which estimates the proportion of phenotypic variance resulting from genetic effects, were higher at early pod filling than at pod setting. Correlations between shoot mass and root mass, which could indicate indirect selection of root systems via aboveground biomass, were higher at early pod filling than at pod setting. The results indicate that selection for root

  10. Effects of liming and wood ash application on root biomass, root distribution and soil chemistry in a Norway spruce stand in southwest Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Viebke, C.G.

    2001-07-01

    Effects of liming (CaPK) and wood ash application (A) on soil chemistry, root (< 2 mm and 2-5 mm in diameter) biomass and distribution, root length density (RLD, cm/cm{sup 3} ) and specific root length (SRL, m/g) were investigated in a 60 year old Norway spruce stand in SW Sweden. Soil cores were taken from the litter fermented humus (LFH) and mineral soil layers to a depth of 30 cm, eight years after treatments. The pH values of the LM layer increased significantly (p< 0.05) in the lime and ash treatments compared to the control, while in the top 5 cm of the mineral soil, pH was increased only in the A treatment compared to CaPK. The P, K, Ca and Mg concentrations increased in the CaPK treatment in the LM layer, while K and Ca decreased significantly at 5-10 cm depth in CaPK treated plots compared to the control and A. The highest amounts of ammonium and nitrate were found in A treatment in all soil layers. The A treatment increased fine root (< 2 mm in diameter) biomass in the LFH layer compared to the control but decreased it in the top 10 cm of the mineral soil compared to CaPK. A shallower fine root system was found in the A treated plots compared to the control and CaPK. The coarser root (2-5 mm in diameter) biomass was higher in the mineral soil in the A treatment compared to the control and CaPK but the differences were not significant. RLD increased in both CaPK and A in the upper soil layers. SRL increased in almost all layers in the CaPK and A treatments compared to the control. The number of root tips were also higher in the treated plots compared to the control, except in the 10-20 cm layer. It was concluded that CaPK and A treatments resulted in improved root vitality with a higher capacity for nutrient uptake.

  11. Total curvature and total torsion of knotted random polygons in confinement

    Science.gov (United States)

    Diao, Yuanan; Ernst, Claus; Rawdon, Eric J.; Ziegler, Uta

    2018-04-01

    Knots in nature are typically confined spatially. The confinement affects the possible configurations, which in turn affects the spectrum of possible knot types as well as the geometry of the configurations within each knot type. The goal of this paper is to determine how confinement, length, and knotting affect the total curvature and total torsion of random polygons. Previously published papers have investigated these effects in the unconstrained case. In particular, we analyze how the total curvature and total torsion are affected by (1) varying the length of polygons within a fixed confinement radius and (2) varying the confinement radius of polygons with a fixed length. We also compare the total curvature and total torsion of groups of knots with similar complexity (measured as crossing number). While some of our results fall in line with what has been observed in the studies of the unconfined random polygons, a few surprising results emerge from our study, showing some properties that are unique due to the effect of knotting in confinement.

  12. Depletion of soil mineral N by roots of ¤Cucumis sativus¤ L. colonized or not by arbuscular mycorrhizal fungi

    DEFF Research Database (Denmark)

    Johansen, A.

    1999-01-01

    on depletion of the soil mineral N pool. All pots were gradually supplied with 31 mg NH4NO3-N kg(-1) dry soil from 12-19 days after planting and an additional 50 mg (NH4)(2)SO4-N kg(-1) dry soil (N-15-labelled in Experiment 1) was supplied at 21 or 22 days after planting in Experiments 1 and 2, respectively....... Dry weight of plant parts, total root length, mycorrhizal colonization rate and soil concentration of NH4+ and NO3- were recorded at five sequential harvest events: 21, 24, 30, 35 and 42 days (Experiment 1) and 22, 25, 28, 31 and 35 days (Experiment 2) after planting. In Experiment 1, plants were also...... in Experiment 2. Mycorrhizal colonization affected the rate of depletion of soil mineral N in Experiment 1, where both NH4+ and NO3- concentrations were markedly lower in the first two harvests, when plants were mycorrhizal. As the root length was similar in mycorrhizal and control treatments, this may indicate...

  13. Genetic linkage map and QTL identification for adventitious rooting traits in red gum eucalypts.

    Science.gov (United States)

    Sumathi, Murugan; Bachpai, Vijaya Kumar Waman; Mayavel, A; Dasgupta, Modhumita Ghosh; Nagarajan, Binai; Rajasugunasekar, D; Sivakumar, Veerasamy; Yasodha, Ramasamy

    2018-05-01

    The eucalypt species, Eucalyptus tereticornis and Eucalyptus camaldulensis , show tolerance to drought and salinity conditions, respectively, and are widely cultivated in arid and semiarid regions of tropical countries. In this study, genetic linkage map was developed for interspecific cross E. tereticornis  ×  E. camaldulensis using pseudo-testcross strategy with simple sequence repeats (SSRs), intersimple sequence repeats (ISSRs), and sequence-related amplified polymorphism (SRAP) markers. The consensus genetic map comprised totally 283 markers with 84 SSRs, 94 ISSRs, and 105 SRAP markers on 11 linkage groups spanning 1163.4 cM genetic distance. Blasting the SSR sequences against E. grandis sequences allowed an alignment of 64% and the average ratio of genetic-to-physical distance was 1.7 Mbp/cM, which strengths the evidence that high amount of synteny and colinearity exists among eucalypts genome. Blast searches also revealed that 37% of SSRs had homologies with genes, which could potentially be used in the variety of downstream applications including candidate gene polymorphism. Quantitative trait loci (QTL) analysis for adventitious rooting traits revealed six QTL for rooting percent and root length on five chromosomes with interval and composite interval mapping. All the QTL explained 12.0-14.7% of the phenotypic variance, showing the involvement of major effect QTL on adventitious rooting traits. Increasing the density of markers would facilitate the detection of more number of small-effect QTL and also underpinning the genes involved in rooting process.

  14. Comparative study of six rotary nickel-titanium systems and hand instrumentation for root canal preparation.

    Science.gov (United States)

    Guelzow, A; Stamm, O; Martus, P; Kielbassa, A M

    2005-10-01

    To compare ex vivo various parameters of root canal preparation using a manual technique and six different rotary nickel-titanium (Ni-Ti) instruments (FlexMaster, System GT, HERO 642, K3, ProTaper, and RaCe). A total of 147 extracted mandibular molars were divided into seven groups (n = 21) with equal mean mesio-buccal root canal curvatures (up to 70 degrees), and embedded in a muffle system. All root canals were prepared to size 30 using a crown-down preparation technique for the rotary nickel-titanium instruments and a standardized preparation (using reamers and Hedströem files) for the manual technique. Length modifications and straightening were determined by standardized radiography and a computer-aided difference measurement for every instrument system. Post-operative cross-sections were evaluated by light-microscopic investigation and photographic documentation. Procedural errors, working time and time for instrumentation were recorded. The data were analysed statistically using the Kruskal-Wallis test and the Mann-Whitney U-test. No significant differences were detected between the rotary Ni-Ti instruments for alteration of working length. All Ni-Ti systems maintained the original curvature well, with minor mean degrees of straightening ranging from 0.45 degrees (System GT) to 1.17 degrees (ProTaper). ProTaper had the lowest numbers of irregular post-operative root canal diameters; the results were comparable between the other systems. Instrument fractures occurred with ProTaper in three root canals, whilst preparation with System GT, HERO 642, K3 and the manual technique resulted in one fracture each. Ni-Ti instruments prepared canals more rapidly than the manual technique. The shortest time for instrumentation was achieved with System GT (11.7 s). Under the conditions of this ex vivo study all Ni-Ti systems maintained the canal curvature, were associated with few instrument fractures and were more rapid than a standardized manual technique. Pro

  15. Quantifying rooting at depth in a wheat doubled haploid population with introgression from wild emmer.

    Science.gov (United States)

    Clarke, Christina K; Gregory, Peter J; Lukac, Martin; Burridge, Amanda J; Allen, Alexandra M; Edwards, Keith J; Gooding, Mike J

    2017-09-01

    The genetic basis of increased rooting below the plough layer, post-anthesis in the field, of an elite wheat line (Triticum aestivum 'Shamrock') with recent introgression from wild emmer (T. dicoccoides), is investigated. Shamrock has a non-glaucous canopy phenotype mapped to the short arm of chromosome 2B (2BS), derived from the wild emmer. A secondary aim was to determine whether genetic effects found in the field could have been predicted by other assessment methods. Roots of doubled haploid (DH) lines from a winter wheat ('Shamrock' × 'Shango') population were assessed using a seedling screen in moist paper rolls, in rhizotrons to the end of tillering, and in the field post-anthesis. A linkage map was produced using single nucleotide polymorphism markers to identify quantitative trait loci (QTLs) for rooting traits. Shamrock had greater root length density (RLD) at depth than Shango, in the field and within the rhizotrons. The DH population exhibited diversity for rooting traits within the three environments studied. QTLs were identified on chromosomes 5D, 6B and 7B, explaining variation in RLD post-anthesis in the field. Effects associated with the non-glaucous trait on RLD interacted significantly with depth in the field, and some of this interaction mapped to 2BS. The effect of genotype was strongly influenced by the method of root assessment, e.g. glaucousness expressed in the field was negatively associated with root length in the rhizotrons, but positively associated with length in the seedling screen. To our knowledge, this is the first study to identify QTLs for rooting at depth in field-grown wheat at mature growth stages. Within the population studied here, our results are consistent with the hypothesis that some of the variation in rooting is associated with recent introgression from wild emmer. The expression of genetic effects differed between the methods of root assessment. © The Author 2017. Published by Oxford University Press on behalf of the

  16. Radiographic Assessment of the Technical Quality and Periapical Health of Root-Filled Teeth Performed by General Practitioners in a Turkish Subpopulation

    Directory of Open Access Journals (Sweden)

    E. Tarim Ertas

    2013-01-01

    Full Text Available Aim. The aim of this study was to evaluate by means of radiographs the technical quality of root fillings performed by dental practitioners. Methods and Material. Standardized periapical radiographs were made on 484 patients who received endodontic treatment in private practice. A total of 831 endodontically treated teeth with 1448 roots were evaluated for technical quality of the root canal filling and the periapical status of the teeth. Also, the apical status of each root-filled tooth was assessed according to the length, density, and taper of root fillings, and the presence of apical transportation, broken root instruments, and overfilled sealer or gutta-percha material was recorded for each root canal. Results. Of the endodontically treated teeth 26.6% had healthy periapical tissues, while technically good endodontic treatment constituted 12.8%. Based on the treatment success, there was no significant difference between the tooth groups. Statistical analysis of the data did not demonstrate statistically significant differences between the various parameters that were evaluated (. Conclusions. Technical quality of root fillings in a population who received treatment in private practice was poor and was consistent with a low prevalence of apical health. The probable reasons for this failure are multifactorial and may be improved if the operators improve their skills with continuing postgraduate education programs.

  17. Adaptive root foraging strategies along a boreal-temperate forest gradient.

    Science.gov (United States)

    Ostonen, Ivika; Truu, Marika; Helmisaari, Heljä-Sisko; Lukac, Martin; Borken, Werner; Vanguelova, Elena; Godbold, Douglas L; Lõhmus, Krista; Zang, Ulrich; Tedersoo, Leho; Preem, Jens-Konrad; Rosenvald, Katrin; Aosaar, Jürgen; Armolaitis, Kęstutis; Frey, Jane; Kabral, Naima; Kukumägi, Mai; Leppälammi-Kujansuu, Jaana; Lindroos, Antti-Jussi; Merilä, Päivi; Napa, Ülle; Nöjd, Pekka; Parts, Kaarin; Uri, Veiko; Varik, Mats; Truu, Jaak

    2017-08-01

    The tree root-mycorhizosphere plays a key role in resource uptake, but also in the adaptation of forests to changing environments. The adaptive foraging mechanisms of ectomycorrhizal (EcM) and fine roots of Picea abies, Pinus sylvestris and Betula pendula were evaluated along a gradient from temperate to subarctic boreal forest (38 sites between latitudes 48°N and 69°N) in Europe. Variables describing tree resource uptake structures and processes (absorptive fine root biomass and morphology, nitrogen (N) concentration in absorptive roots, extramatrical mycelium (EMM) biomass, community structure of root-associated EcM fungi, soil and rhizosphere bacteria) were used to analyse relationships between root system functional traits and climate, soil and stand characteristics. Absorptive fine root biomass per stand basal area increased significantly from temperate to boreal forests, coinciding with longer and thinner root tips with higher tissue density, smaller EMM biomass per root length and a shift in soil microbial community structure. The soil carbon (C) : N ratio was found to explain most of the variability in absorptive fine root and EMM biomass, root tissue density, N concentration and rhizosphere bacterial community structure. We suggest a concept of absorptive fine root foraging strategies involving both qualitative and quantitative changes in the root-mycorrhiza-bacteria continuum along climate and soil C : N gradients. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  18. Prevalence and morphometric analysis of three-rooted mandibular first molars in a Brazilian subpopulation

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    Clarissa Teles Rodrigues

    Full Text Available ABSTRACT The knowledge of the internal anatomy of three-rooted mandibular molars may help clinicians to diagnose and plan the root canal treatment in order to provide adequate therapy when this variation is present. Objectives: To determine the prevalence of three-rooted mandibular molars in a Brazilian population using cone beam computed tomography (CBCT and to analyze the anatomy of mandibular first molars with three roots through micro-CT. Material and Methods: CBCT images of 116 patients were reviewed to determine the prevalence of three-rooted first mandibular molars in a Brazilian subpopulation. Furthermore, with the use of micro-CT, 55 extracted three-rooted mandibular first molars were scanned and reconstructed to assess root length, distance between canal orifices, apical diameter, Vertucci's classification, presence of apical delta, number of foramina and furcations, lateral and accessory canals. The distance between the orifice on the pulp chamber floor and the beginning of the curvature and the angle of canal curvature were analyzed in the distolingual root. Data were compared using the Kruskal-Wallis test (α=0.05. Results: The prevalence of three-rooted mandibular first molars was of 2.58%. Mesial roots showed complex distribution of the root canal system in comparison to the distal roots. The median of major diameters of mesiobuccal, mesiolingual and single mesial canals were: 0.34, 0.41 and 0.60 mm, respectively. The higher values of major diameters were found in the distobuccal canals (0.56 mm and the lower diameters in the distolingual canals (0.29 mm. The lowest orifice distance was found between the mesial canals (MB-ML and the highest distance between the distal root canals (DB-DL. Almost all distal roots had one root canal and one apical foramen with few accessory canals. Conclusions: Distolingual root generally has short length, severe curvature and a single root canal with low apical diameter.

  19. Effects of free-air CO2 enrichment on adventitious root development of rice under low and normal soil nitrogen levels

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    Chengming Sun

    2014-08-01

    Full Text Available Free air CO2 enrichment (FACE and nitrogen (N have marked effects on rice root growth, and numerical simulation can explain these effects. To further define the effects of FACE on root growth of rice, an experiment was performed, using the hybrid indica cultivar Xianyou 63. The effects of increasing atmospheric CO2 concentration [CO2], 200 μmol mol− 1 higher than ambient, on the growth of rice adventitious roots were evaluated, with two levels of N: low (LN, 125 kg ha− 1 and normal (NN, 250 kg ha− 1. The results showed a significant increase in both adventitious root number (ARN and adventitious root length (ARL under FACE treatment. The application of nitrogen also increased ARN and ARL, but these increases were smaller than that under FACE treatment. On the basis of the FACE experiment, numerical models for rice adventitious root number and length were constructed with time as the driving factor. The models illustrated the dynamic development of rice adventitious root number and length after transplanting, regulated either by atmospheric [CO2] or by N application. The simulation result was supported by statistical tests comparing experimental data from different years, and the model yields realistic predictions of root growth. These results suggest that the models have strong predictive potential under conditions of atmospheric [CO2] rises in the future.

  20. Radiographic technical quality of root canal treatment performed by a new rotary single-file system.

    Science.gov (United States)

    Colombo, Marco; Bassi, Cristina; Beltrami, Riccardo; Vigorelli, Paolo; Spinelli, Antonio; Cavada, Andrea; Dagna, Alberto; Chiesa, Marco; Poggio, Claudio

    2017-01-01

    The aim of the present study was to evaluate radiographically the technical quality of root canal filling performed by postgraduate students with a new single-file Nickel-Titanium System (F6 Skytaper Komet) in clinical practice. Records of 74 patients who had received endodontic treatment by postgraduate students at the School of Dentistry, Faculty of Medicine, University of Pavia in the period between September 2015 and April 2016 were collected and examined: the final sample consisted 114 teeth and 204 root canals. The quality of endodontic treatment was evaluated by examining the length of the filling in relation to the radiographic apex, the density of the obturation according to the presence of voids and the taper of root canal filling. Chi-squared analysis was used to determine statistically significant differences between the technical quality of root fillings according to tooth's type, position and curvature. The results showed that 75,49%, 82,84% and 90,69% of root filled canals had adequate length, density and taper respectively. Overall, the technical quality of root canal fillings performed by postgraduates students was acceptable in 60,78% of the cases.

  1. A major QTL controlling deep rooting on rice chromosome 4.

    Science.gov (United States)

    Uga, Yusaku; Yamamoto, Eiji; Kanno, Noriko; Kawai, Sawako; Mizubayashi, Tatsumi; Fukuoka, Shuichi

    2013-10-24

    Drought is the most serious abiotic stress that hinders rice production under rainfed conditions. Breeding for deep rooting is a promising strategy to improve the root system architecture in shallow-rooting rice cultivars to avoid drought stress. We analysed the quantitative trait loci (QTLs) for the ratio of deep rooting (RDR) in three F₂ mapping populations derived from crosses between each of three shallow-rooting varieties ('ARC5955', 'Pinulupot1', and 'Tupa729') and a deep-rooting variety, 'Kinandang Patong'. In total, we detected five RDR QTLs on chromosomes 2, 4, and 6. In all three populations, QTLs on chromosome 4 were found to be located at similar positions; they explained from 32.0% to 56.6% of the total RDR phenotypic variance. This suggests that one or more key genetic factors controlling the root growth angle in rice is located in this region of chromosome 4.

  2. Estimation of runoff mitigation by morphologically different cover crop root systems

    Science.gov (United States)

    Yu, Yang; Loiskandl, Willibald; Kaul, Hans-Peter; Himmelbauer, Margarita; Wei, Wei; Chen, Liding; Bodner, Gernot

    2016-07-01

    Hydrology is a major driver of biogeochemical processes underlying the distinct productivity of different biomes, including agricultural plantations. Understanding factors governing water fluxes in soil is therefore a key target for hydrological management. Our aim was to investigate changes in soil hydraulic conductivity driven by morphologically different root systems of cover crops and their impact on surface runoff. Root systems of twelve cover crop species were characterized and the corresponding hydraulic conductivity was measured by tension infiltrometry. Relations of root traits to Gardner's hydraulic conductivity function were determined and the impact on surface runoff was estimated using HYDRUS 2D. The species differed in both rooting density and root axes thickness, with legumes distinguished by coarser axes. Soil hydraulic conductivity was changed particularly in the plant row where roots are concentrated. Specific root length and median root radius were the best predictors for hydraulic conductivity changes. For an intensive rainfall simulation scenario up to 17% less rainfall was lost by surface runoff in case of the coarsely rooted legumes Melilotus officinalis and Lathyrus sativus, and the densely rooted Linum usitatissimum. Cover crops with coarse root axes and high rooting density enhance soil hydraulic conductivity and effectively reduce surface runoff. An appropriate functional root description can contribute to targeted cover crop selection for efficient runoff mitigation.

  3. Root and Nodulation Phenotypes of the Ethylene-Insensitive Sickle Mutant of Medicago truncatula

    Directory of Open Access Journals (Sweden)

    JOKO PRAYITNO

    2010-09-01

    Full Text Available The sickle (skl mutant of the model legume Medicago truncatula is an ethylene-sensitive mutant that have a ten-fold increase in nodule numbers. The nodulation and root phenotypes of the skl mutant were investigated and further characterised. The skl mutant had longer roots than the wild type, but when inoculated with Sinorhizobium, its root length was reduced to the level of wild type. Furthermore, lateral root numbers in uninoculated skl were similar to those in uninoculated wild type. However, when the root tips were decapitated, fewer lateral roots formed in skl than in wild type. Nodule numbers of the skl mutant were significantly reduced by low nitrate concentration (2.5 mM. These results suggest that skl mutant has alterations in both root and nodule development.

  4. Rooting and acclimatization of the Japanese plum tree, cv. América

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    Juliana de Magalhães Bandeira

    2012-06-01

    Full Text Available Rooting and acclimatization are limiting steps in plant micropropagation, especially in woody plant species. This study aimed to evaluate the IAA and IBA effect on the in vitro rooting and acclimatization of micropropagated shoots of Japanese plum (Prunus salicina Lindl. cv. América. Shoots from 3 to 4 cm long were inoculated in MS medium with half salt and vitamin concentrations (MS/2 added with IAA and IBA (0, 0.25, 0.5, 0.75 and 1 mg L-1. After a 20-day period in in vitro cultivation, the shoots were evaluated, and then transferred to a greenhouse, and evaluated after 30 days. At the end of the in vitro cultivation period, no significant interactions were observed for number of roots per shoot and rooting percentage, but a significant effect was recorded for auxin type only, for which shoots grown in media added with IBA showed high values - 0.87 and 41.95%, respectively. A linear increase response from 1.45 to 5.75 cm was verified for root length of shoots cultivated in IBA medium; however, no significant effect was observed, and a 0.86 cm average root length per shoot grown in medium added with IAA was found. After 30 days of acclimatization period, the largest survival percentage was obtained from shoots cultivated in medium with 1 mg L-1 of IBA and IAA (88% and 92%, respectively. Although, IBA provided the highest in vitro rooting, most of the surviving shoots were those originated in IAA-added medium, probably because IBA promoted longer fibrous roots, less appropriate for transplant and soil fixation, as they are easily damaged. It was concluded that in vitro rooting with the addition of the highest IAA concentration (1 mg L-1 provided the greatest plant survival during the acclimatization period of the Japanese plum cv. América.

  5. Rooting of hardwood cuttings of Roxo de Valinhos fig (Ficus carica L. with different propagation strategies

    Directory of Open Access Journals (Sweden)

    Gilmar Antônio Nava

    2014-12-01

    Full Text Available The objective of this study was to evaluate the substrate, cuttings collection time, the position and the cutting depth, and the propagation environment on rooting of 'Purple Valinhos' fig tree cuttings in Southwestern Paraná, Brazil. Two experiments were carried out at UTFPR, Câmpus Dois Vizinhos, with hardwoods cuttings from Roxo de Valinhos fig tree. The first experiment used a randomized block design, in 3 x 3 x 2 factorial (substrate x environment x collection time, with four replications of 10 cuttings per plot. The cuttings were collected in the first fifteen days of July and August. The substrates were sand, soil and the mixture of these [1:1 (v / v]. The environments used were open sky, tunnel with plastic cover and tunnel with half-shade black net cover. The second experiment used a randomized block design, 2 x 2 x 3 factorial (shoot cutting position x soil cover x shoot cutting depth, with four replications of 12 cuttings per plot. In the factor position, the vertically (0 º inclination and inclined (45 º inclination shoot cuttings were evaluated. Soil cover was tested with mulching plastic cover or not. The tested depths were 1/3, 1/2 and 2/3 in relation to the total length of the shoot cutting. In both experiments, the following were analyzed: rooting and mortality indices, number of leaves and primary shoots, length of the three largest roots per cutting. It was conclude that, the protected environment with plastic cover on sand as substrate must recommended for the rooting of fig estaca, collecting them in the first half of July. The inclination position and cutting depth of the estaca and the substrate coverage with plastic mulching did not influence the results.

  6. A scanning electron microscopic study of the patterns of external root resorption under different conditions

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    Ravindran Sreeja

    2009-10-01

    Full Text Available OBJECTIVE: The aim of this study was to examine if there are qualitative differences in the appearance of external root resorption patterns of primary teeth undergoing physiologic resorption and permanent teeth undergoing pathological root resorption in different conditions. MATERIAL AND METHODS: A total of 40 teeth undergoing external root resorption in different conditions were divided into 4 groups and prepared for examination under scanning electron microscopy at magnifications ranging from 20x to 1000x. Group I: 10 primary molars exfoliated due to physiologic root resorption; Group II: 10 permanent teeth with periapical granulomas showing signs of resorption; Group III:10 permanent teeth therapeutically extracted during the course of orthodontic therapy with evidence of resorption, and Group IV: 10 permanent teeth associated with odontogenic tumors that showed evidence of resorption. RESULTS: In Group I, the primary teeth undergoing resorption showed smooth extensive and predominantly regular areas reflecting the slow ongoing physiologic process. In Group II, the teeth with periapical granulomas showed the resorption was localized to apex with a funnel shaped appearance in most cases. Teeth in Group III, which had been subjected to a short period of light orthodontic force, showed the presence of numerous resorption craters with adjoining areas of cemental repair in some cases. Teeth associated with odontogenic tumors in Group IV showed many variations in the patterns of resorption with extensive loss of root length and a sharp cut appearance of the root in most cases. CONCLUSION: Differences were observed in the patterns of external root resorption among the studied groups of primary and permanent teeth under physiologic and pathological conditions.

  7. Comprimento da estaca no desenvolvimento de mudas de alecrim-pimenta Effect of cutting length on the development of pepper-rosmarin seedlings

    Directory of Open Access Journals (Sweden)

    Wellington Geraldo Oliveira Carvalho Júnior

    2009-10-01

    Full Text Available O objetivo deste trabalho foi avaliar a influência do comprimento de estacas caulinares no desenvolvimento de mudas de alecrim-pimenta (Lippia sidoides Cham.. As estacas foram coletadas de plantas matrizes do Horto Medicinal do Instituto de Ciências Agrárias da Universidade Federal de Minas Gerais, em Montes Claros, Minas Gerais. O experimento foi conduzido em casa de vegetação com nebulização intermitente. Utilizou-se o delineamento inteiramente casualizado, com quatro tratamentos e cinco repetições. Os tratamentos foram definidos pelos intervalos de comprimento das estacas (5 a 8cm, 8,1 a 11cm, 11,1 a 14cm e 14,1 a 17cm. Foram avaliados o número de raízes principais, o comprimento da maior raiz (cm, o número de brotações, a porcentagem de enraizamento, a avaliação visual do enraizamento e a fitomassa seca das brotações e das raízes (g. Os resultados indicam que o comprimento das estacas afeta o desenvolvimento de mudas de alecrim-pimenta, especialmente a fitomassa seca das brotações e das raízes. As estacas com 14,1 a 17cm apresentaram a maior porcentagem de enraizamento e as maiores médias para as outras variáveis analisadas, sendo, portanto, mais recomendadas para a propagação vegetativa de alecrim-pimenta.This research aimed to evaluate the effect of shoot cutting length on the development of pepper-rosmarin seedlings (Lippia sidoides Cham.. The cuttings were obtained from stock plants of the medicinal vegetable garden of Instituto de Ciências Agrárias/UFMG, Montes Claros, Minas Gerais, Brazil. The experiment was conducted in greenhouse conditions with intermittent mist. The experimental design was totally randomized with four treatments consisted of different size intervals (5 to 8cm, 8.1 to 11cm, 11.1 to 14cm and 14.1 to 17cm, with five replications each. The amount of shooting and root, the shooting and root dry weight (g, the the longest root length (cm, the visual rooting evaluation and the rooting

  8. Iron and ferritin dependent ROS distribution impact Arabidopsis root system architecture.

    Science.gov (United States)

    Reyt, Guilhem; Boudouf, Soukaina; Boucherez, Jossia; Gaymard, Frédéric; Briat, Jean-Franois

    2014-11-09

    Iron (Fe) homeostasis is integrated with the production of Reactive Oxygen Species (ROS) whose distribution at the root tip participates in the control of root growth. Excess Fe increases ferritin abundance, enabling the storage of Fe which contributes to protection of plants against Fe-induced oxidative stress. AtFer1 and AtFer3 are the two ferritin genes expressed in the meristematic zone, pericycle and endodermis of the Arabidopsis thaliana (Arabidopsis) root, and it is in these regions that we observe Fe stained dots. This staining disappears in the triple fer1-3-4 ferritin mutant. Fe excess decreases primary root length in the same way in wild-type and in fer1-3-4 mutant. In contrast, the Fe mediated decrease of lateral root (LR) length and density is enhanced in fer1-3-4 plants due to a defect in LR emergence. We observe that this interaction between excess Fe, ferritin and RSA is in part mediated by the H 2 O 2 /O 2 .- balance between the root cell proliferation and differentiation zones regulated by the UPB1 transcription factor. Further, meristem size is also decreased in response to Fe excess in ferritin mutant plants, implicating cell cycle arrest mediated by the ROS-activated SMR5/SMR7 cyclin-dependent kinase inhibitors pathway in the interaction between Fe and RSA. © The Author 2014. Published by the Molecular Plant Shanghai Editorial Office in association with Oxford University Press on behalf of CSPB and IPPE, SIBS, CAS.

  9. Does species richness affect fine root biomass and production in young forest plantations?

    Science.gov (United States)

    Domisch, Timo; Finér, Leena; Dawud, Seid Muhie; Vesterdal, Lars; Raulund-Rasmussen, Karsten

    2015-02-01

    Tree species diversity has been reported to increase forest ecosystem above-ground biomass and productivity, but little is known about below-ground biomass and production in diverse mixed forests compared to single-species forests. For testing whether species richness increases below-ground biomass and production and thus complementarity between forest tree species in young stands, we determined fine root biomass and production of trees and ground vegetation in two experimental plantations representing gradients in tree species richness. Additionally, we measured tree fine root length and determined species composition from fine root biomass samples with the near-infrared reflectance spectroscopy method. We did not observe higher biomass or production in mixed stands compared to monocultures. Neither did we observe any differences in tree root length or fine root turnover. One reason for this could be that these stands were still young, and canopy closure had not always taken place, i.e. a situation where above- or below-ground competition did not yet exist. Another reason could be that the rooting traits of the tree species did not differ sufficiently to support niche differentiation. Our results suggested that functional group identity (i.e. conifers vs. broadleaved species) can be more important for below-ground biomass and production than the species richness itself, as conifers seemed to be more competitive in colonising the soil volume, compared to broadleaved species.

  10. A Rare Case of Apical Root Resorption during Orthodontic Treatment of Patient with Multiple Aplasia

    OpenAIRE

    Agrawal, Chintan M; Mahida, Khyati; Agrawal, Charu C; Bothra, Jitendrakumar; Mashru, Ketan

    2015-01-01

    External apical root resorption is an adverse effect of orthodontic treatment. It reduces the length of root and breaks the integrity of teeth and dental arch. Orthodontics is the only dental specialty that clinically uses the inflammatory process to correct the mal-aligned teeth. Hence, it is necessary to know the risk factors of root resorption and do everything to reduce the rate of root resorption. Hence, all predisposing factors which are systemic as well as local should be considered be...

  11. Dark exposure of petunia cuttings strongly improves adventitious root formation and enhances carbohydrate availability during rooting in the light.

    Science.gov (United States)

    Klopotek, Yvonne; Haensch, Klaus-Thomas; Hause, Bettina; Hajirezaei, Mohammad-Reza; Druege, Uwe

    2010-05-01

    The effect of temporary dark exposure on adventitious root formation (ARF) in Petuniaxhybrida 'Mitchell' cuttings was investigated. Histological and metabolic changes in the cuttings during the dark treatment and subsequent rooting in the light were recorded. Excised cuttings were exposed to the dark for seven days at 10 degrees C followed by a nine-day rooting period in perlite or were rooted immediately for 16 days in a climate chamber at 22/20 degrees C (day/night) and a photosynthetic photon flux density (PPFD) of 100micromolm(-2)s(-1). Dark exposure prior to rooting increased, accelerated and synchronized ARF. The rooting period was reduced from 16 days (non-treated cuttings) to 9 days (treated cuttings). Under optimum conditions, despite the reduced rooting period, dark-exposed cuttings produced a higher number and length of roots than non-treated cuttings. An increase in temperature to 20 degrees C during the dark treatment or extending the cold dark exposure to 14 days caused a similar enhancement of root development compared to non-treated cuttings. Root meristem formation had already started during the dark treatment and was enhanced during the subsequent rooting period. Levels of soluble sugars (glucose, fructose and sucrose) and starch in leaf and basal stem tissues significantly decreased during the seven days of dark exposure. This depletion was, however, compensated during rooting after 6 and 24h for soluble sugars in leaves and the basal stem, respectively, whereas the sucrose level in the basal stem was already increased at 6h. The association of higher carbohydrate levels with improved rooting in previously dark-exposed versus non-treated cuttings indicates that increased post-darkness carbohydrate availability and allocation towards the stem base contribute to ARF under the influence of dark treatment and provide energy for cell growth subject to a rising sink intensity in the base of the cutting. Copyright 2009 Elsevier GmbH. All rights reserved.

  12. Quantitative imaging of radial oxygen loss from Valisneria spiralis roots with a fluorescent planar optode

    International Nuclear Information System (INIS)

    Han, Chao; Ren, Jinghua; Tang, Hao; Xu, Di; Xie, Xianchuan

    2016-01-01

    Oxygen (O_2) availability within the sediment–root interface is critical to the survival of macrophytes in O_2-deficient sediment; however, our knowledge of the fine-scale impact of macrophyte roots upon the spatiotemporal dynamics of O_2 is relatively limited. In this study, a non-invasive imaging technology was utilized to map O_2 micro-distribution around Vallisneria spiralis. Long-term imaging results gathered during a 36 day-period revealed an abundance of O_2 spatiotemporal patterns ranging from 0 to 250 μmol L"− "1. The root-induced O_2 leakage and consequent oxygenated area were stronger in the vicinity of the basal root compared to that found in the root tip. The O_2 images revealed V. spiralis exhibited radial O_2 loss (ROL) along the entire root, and the O_2 distribution along the root length showed a high degree of small-scale spatial heterogeneity decreasing from 80% at the basal root surface to 10% at the root tip. The oxygenated zone area around the roots increased as O_2 levels increased with root growth and irradiance intensities ranging from 0 to 216 μmol photons m"− "2 s"− "1. A weak ROL measuring < 20% air saturation around the basal root surface was maintained in darkness, which was presumably attributed to the O_2 supply from overlying water via plant aerenchyma. The estimated total O_2 release to the rhizosphere of V. spiralis was determined to range from 8.80 ± 7.32 to 30.34 ± 17.71 nmol m"− "2 s"− "1, which is much higher than many other macrophyte species. This O_2 release may be an important contribution to the high-capacity of V. spiralis for quickly colonizing anaerobic sediment. - Highlights: • Planar imaging method was used to map O2 micro-distribution. • Highly dynamic rhizospheric O2-spatiotemporal distribution was observed. • O_2 leakage along the entire root of Vallisneria spirals were defined. • The ROL rates of 8.80–30.34 nmol m"− "2 s"− "1 were measured over a 36-day growth. • ROL was closely

  13. Differential effects of fine root morphology on water dynamics in the root-soil interface

    Science.gov (United States)

    DeCarlo, K. F.; Bilheux, H.; Warren, J.

    2017-12-01

    Soil water uptake form plants, particularly in the rhizosphere, is a poorly understood question in the plant and soil sciences. Our study analyzed the role of belowground plant morphology on soil structural and water dynamics of 5 different plant species (juniper, grape, maize, poplar, maple), grown in sandy soils. Of these, the poplar system was extended to capture drying dynamics. Neutron radiography was used to characterize in-situ dynamics of the soil-water-plant system. A joint map of root morphology and soil moisture was created for the plant systems using digital image processing, where soil pixels were connected to associated root structures via minimum distance transforms. Results show interspecies emergent behavior - a sigmoidal relationship was observed between root diameter and bulk/rhizosphere soil water content difference. Extending this as a proxy for extent of rhizosphere development with root age, we observed a logistic growth pattern for the rhizosphere: minimal development in the early stages is superceded by rapid onset of rhizosphere formation, which then stabilizes/decays with the likely root suberization. Dynamics analysis of water content differences between the root/rhizosphere, and rhizosphere/bulk soil interface highlight the persistently higher water content in the root at all water content and root size ranges. At the rhizosphere/bulk soil interface, we observe a shift in soil water dynamics by root size: in super fine roots, we observe that water content is primarily lower in the rhizosphere under wetter conditions, which then gradually increases to a relatively higher water content under drier conditions. This shifts to a persistently higher rhizosphere water content relative to bulk soil in both wet/dry conditions with increased root size, suggesting that, by size, the finest root structures may contribute the most to total soil water uptake in plants.

  14. Jatropha curcas L. Root Structure and Growth in Diverse Soils

    Science.gov (United States)

    Valdés-Rodríguez, Ofelia Andrea; Sánchez-Sánchez, Odilón; Pérez-Vázquez, Arturo; Caplan, Joshua S.; Danjon, Frédéric

    2013-01-01

    Unlike most biofuel species, Jatropha curcas has promise for use in marginal lands, but it may serve an additional role by stabilizing soils. We evaluated the growth and structural responsiveness of young J. curcas plants to diverse soil conditions. Soils included a sand, a sandy-loam, and a clay-loam from eastern Mexico. Growth and structural parameters were analyzed for shoots and roots, although the focus was the plasticity of the primary root system architecture (the taproot and four lateral roots). The sandy soil reduced the growth of both shoot and root systems significantly more than sandy-loam or clay-loam soils; there was particularly high plasticity in root and shoot thickness, as well as shoot length. However, the architecture of the primary root system did not vary with soil type; the departure of the primary root system from an index of perfect symmetry was 14 ± 5% (mean ± standard deviation). Although J. curcas developed more extensively in the sandy-loam and clay-loam soils than in sandy soil, it maintained a consistent root to shoot ratio and root system architecture across all types of soil. This strong genetic determination would make the species useful for soil stabilization purposes, even while being cultivated primarily for seed oil. PMID:23844412

  15. Jatropha curcas L. root structure and growth in diverse soils.

    Science.gov (United States)

    Valdés-Rodríguez, Ofelia Andrea; Sánchez-Sánchez, Odilón; Pérez-Vázquez, Arturo; Caplan, Joshua S; Danjon, Frédéric

    2013-01-01

    Unlike most biofuel species, Jatropha curcas has promise for use in marginal lands, but it may serve an additional role by stabilizing soils. We evaluated the growth and structural responsiveness of young J. curcas plants to diverse soil conditions. Soils included a sand, a sandy-loam, and a clay-loam from eastern Mexico. Growth and structural parameters were analyzed for shoots and roots, although the focus was the plasticity of the primary root system architecture (the taproot and four lateral roots). The sandy soil reduced the growth of both shoot and root systems significantly more than sandy-loam or clay-loam soils; there was particularly high plasticity in root and shoot thickness, as well as shoot length. However, the architecture of the primary root system did not vary with soil type; the departure of the primary root system from an index of perfect symmetry was 14 ± 5% (mean ± standard deviation). Although J. curcas developed more extensively in the sandy-loam and clay-loam soils than in sandy soil, it maintained a consistent root to shoot ratio and root system architecture across all types of soil. This strong genetic determination would make the species useful for soil stabilization purposes, even while being cultivated primarily for seed oil.

  16. Jatropha curcas L. Root Structure and Growth in Diverse Soils

    Directory of Open Access Journals (Sweden)

    Ofelia Andrea Valdés-Rodríguez

    2013-01-01

    Full Text Available Unlike most biofuel species, Jatropha curcas has promise for use in marginal lands, but it may serve an additional role by stabilizing soils. We evaluated the growth and structural responsiveness of young J. curcas plants to diverse soil conditions. Soils included a sand, a sandy-loam, and a clay-loam from eastern Mexico. Growth and structural parameters were analyzed for shoots and roots, although the focus was the plasticity of the primary root system architecture (the taproot and four lateral roots. The sandy soil reduced the growth of both shoot and root systems significantly more than sandy-loam or clay-loam soils; there was particularly high plasticity in root and shoot thickness, as well as shoot length. However, the architecture of the primary root system did not vary with soil type; the departure of the primary root system from an index of perfect symmetry was 14±5% (mean ± standard deviation. Although J. curcas developed more extensively in the sandy-loam and clay-loam soils than in sandy soil, it maintained a consistent root to shoot ratio and root system architecture across all types of soil. This strong genetic determination would make the species useful for soil stabilization purposes, even while being cultivated primarily for seed oil.

  17. In vitro comparison of working length determination using three different electronic apex locators

    Directory of Open Access Journals (Sweden)

    Alper Kuştarci

    2014-01-01

    Full Text Available Background: The aim of this study was to compare the accuracy of the apex-locating functions of DentaPort ZX, Raypex 5 and Endo Master electronic apex locators (EALs in vitro. Materials and Methods: Thirty extracted human single-rooted teeth with mature apices were used for the study. The real working length (RWL was established by subtracting 0.5 mm from the actual root canal length. All teeth were mounted in an alginate model that was especially developed to test the EALs and the teeth were then measured with each EAL. The results were compared with the corresponding RWL, which was subtracted from the electronically determined distance. Data were analyzed using a paired-samples t-test, a Chi-square test and a repeated measure analysis of variance evaluation at the 0.05 level of significance. Results: Statistical analysis showed that no significant difference was found among all EALs (P > 0.05. Conclusion: The accuracy of the EALs was evaluated and all of the devices showed an acceptable determination of electronic working length between the ranges of ±0.5 mm.

  18. Analysis of dental root apical morphology: a new method for dietary reconstructions in primates.

    Science.gov (United States)

    Hamon, NoÉmie; Emonet, Edouard-Georges; Chaimanee, Yaowalak; Guy, Franck; Tafforeau, Paul; Jaeger, Jean-Jacques

    2012-06-01

    The reconstruction of paleo-diets is an important task in the study of fossil primates. Previously, paleo-diet reconstructions were performed using different methods based on extant primate models. In particular, dental microwear or isotopic analyses provided accurate reconstructions for some fossil primates. However, there is sometimes difficult or impossible to apply these methods to fossil material. Therefore, the development of new, independent methods of diet reconstructions is crucial to improve our knowledge of primates paleobiology and paleoecology. This study aims to investigate the correlation between tooth root apical morphology and diet in primates, and its potential for paleo-diet reconstructions. Dental roots are composed of two portions: the eruptive portion with a smooth and regular surface, and the apical penetrative portion which displays an irregular and corrugated surface. Here, the angle formed by these two portions (aPE), and the ratio of penetrative portion over total root length (PPI), are calculated for each mandibular tooth root. A strong correlation between these two variables and the proportion of some food types (fruits, leaves, seeds, animal matter, and vertebrates) in diet is found, allowing the use of tooth root apical morphology as a tool for dietary reconstructions in primates. The method was then applied to the fossil hominoid Khoratpithecus piriyai, from the Late Miocene of Thailand. The paleo-diet deduced from aPE and PPI is dominated by fruits (>50%), associated with animal matter (1-25%). Leaves, vertebrates and most probably seeds were excluded from the diet of Khoratpithecus, which is consistent with previous studies. Copyright © 2012 Wiley Periodicals, Inc.

  19. A bell pepper cultivar tolerant to chilling enhanced nitrogen allocation and stress-related metabolite accumulation in the roots in response to low root-zone temperature.

    Science.gov (United States)

    Aidoo, Moses Kwame; Sherman, Tal; Lazarovitch, Naftali; Fait, Aaron; Rachmilevitch, Shimon

    2017-10-01

    Two bell pepper (Capsicum annuum) cultivars, differing in their response to chilling, were exposed to three levels of root-zone temperatures. Gas exchange, shoot and root phenology, and the pattern of change of the central metabolites and secondary metabolites caffeate and benzoate in the leaves and roots were profiled. Low root-zone temperature significantly inhibited gaseous exchange, with a greater effect on the sensitive commercial pepper hybrid (Canon) than on the new hybrid bred to enhance abiotic stress tolerance (S103). The latter was less affected by the treatment with respect to plant height, shoot dry mass, root maximum length, root projected area, number of root tips and root dry mass. More carbon was allocated to the leaves of S103 than nitrogen at 17°C, while in the roots at 17°C, more nitrogen was allocated and the ratio between C/N decreased. Metabolite profiling showed greater increase in the root than in the leaves. Leaf response between the two cultivars differed significantly. The roots accumulated stress-related metabolites including γ-aminobutyric acid (GABA), proline, galactinol and raffinose and at chilling (7°C) resulted in an increase of sugars in both cultivars. Our results suggest that the enhanced tolerance of S103 to root cold stress, reflected in the relative maintenance of shoot and root growth, is likely linked to a more effective regulation of photosynthesis facilitated by the induction of stress-related metabolism. © 2017 Scandinavian Plant Physiology Society.

  20. Diferentes substratos e ambientes no enraizamento in vitro de mirtilo Different substrates and environment conditions on in vitro rooting of blueberry

    Directory of Open Access Journals (Sweden)

    Cláudia Roberta Damiani

    2009-04-01

    Full Text Available O objetivo neste trabalho foi comparar a capacidade de enraizamento in vitro de mirtilo (Vaccinium ashei Reade cv. 'Delite' e V. corymbosum L. cv. 'Georgiagem' e estudar o efeito de substratos alternativos ao ágar (perlita, vermiculita e ágar + carvão ativado adicionados ao meio de cultura 'WPM' contendo 7µM L-1 de AIB e o efeito da luminosidade por meio do cultivo em diferentes ambientes: sala de crescimento convencional e casa de vegetação. Concluiu-se que o uso de perlita, seguido da vermiculita, promovem o aumento do número e comprimento de raízes, matéria fresca total e radicular e maiores porcentagens de enraizamento. A adição de carvão ativado inibe o enraizamento. O ambiente de cultivo não alterou o número de raízes formadas. A cultivar 'Georgiagem' apresentou maiores porcentagens de enraizamento quando comparada a cv. 'Delite', independentemente do local de cultivo e substrato.The aim of this research was to compare the in vitro rooting ability of blueberry (Vaccinium ashei Reade cv. 'Delite' and V. corymbosum L. cv. 'Georgiagem', to study the effect of alternative substrate instead of agar (perlite, vermiculite and agar + activated charcoal added to the WPM culture medium containing 7µM L-1 of AIB, and the light effect by raising the explants in different growth environment: conventional growth room and greenhouse. The use of perlite followed by vermiculite increased roots number and length, total fresh weight and root weight and rooting percentage. The addition of activated charcoal inhibited rooting. The environment condition did not alter the number of formed roots. The cv. 'Georgiagem' showed the highest percentages of rooting whether compared cv. 'Delite', independently of growth environment and substrate.

  1. Integration of root phenes revealed by intensive phenotyping of root system architecture, anatomy, and physiology in cereals

    Science.gov (United States)

    York, Larry

    2015-04-01

    Food insecurity is among the greatest challenges humanity will face in the 21st century. Agricultural production in much of the world is constrained by the natural infertility of soil which restrains crops from reaching their yield potential. In developed nations, fertilizer inputs pollute air and water and contribute to climate change and environmental degradation. In poor nations low soil fertility is a primary constraint to food security and economic development. Water is almost always limiting crop growth in any system. Increasing the acquisition efficiency of soil resources is one method by which crop yields could be increased without the use of more fertilizers or irrigation. Cereals are the most widely grown crops, both in terms of land area and in yield, so optimizing uptake efficiency of cereals is an important goal. Roots are the primary interface between plant and soil and are responsible for the uptake of soil resources. The deployment of roots in space and time comprises root system architecture (RSA). Cereal RSA is a complex phenotype that aggregates many elemental phenes (elemental units of phenotype). Integration of root phenes will be determined by interactions through their effects on soil foraging and plant metabolism. Many architectural, metabolic, and physiological root phenes have been identified in maize, including: nodal root number, nodal root growth angle, lateral root density, lateral root length, aerenchyma, cortical cell size and number, and nitrate uptake kinetics. The utility of these phenes needs confirmation in maize and in other cereals. The maize root system is composed of an embryonic root system and nodal roots that emerge in successive whorls as the plant develops, and is similar to other cereals. Current phenotyping platforms often ignore the inner whorls and instead focus on the most visible outer whorls after excavating a maize root crown from soil. Here, an intensive phenotyping platform evaluating phenes of all nodal root

  2. A Novel Strategy to Engineer Pre-Vascularized Full-Length Dental Pulp-like Tissue Constructs.

    Science.gov (United States)

    Athirasala, Avathamsa; Lins, Fernanda; Tahayeri, Anthony; Hinds, Monica; Smith, Anthony J; Sedgley, Christine; Ferracane, Jack; Bertassoni, Luiz E

    2017-06-12

    The requirement for immediate vascularization of engineered dental pulp poses a major hurdle towards successful implementation of pulp regeneration as an effective therapeutic strategy for root canal therapy, especially in adult teeth. Here, we demonstrate a novel strategy to engineer pre-vascularized, cell-laden hydrogel pulp-like tissue constructs in full-length root canals for dental pulp regeneration. We utilized gelatin methacryloyl (GelMA) hydrogels with tunable physical and mechanical properties to determine the microenvironmental conditions (microstructure, degradation, swelling and elastic modulus) that enhanced viability, spreading and proliferation of encapsulated odontoblast-like cells (OD21), and the formation of endothelial monolayers by endothelial colony forming cells (ECFCs). GelMA hydrogels with higher polymer concentration (15% w/v) and stiffness enhanced OD21 cell viability, spreading and proliferation, as well as endothelial cell spreading and monolayer formation. We then fabricated pre-vascularized, full-length, dental pulp-like tissue constructs by dispensing OD21 cell-laden GelMA hydrogel prepolymer in root canals of extracted teeth and fabricating 500 µm channels throughout the root canals. ECFCs seeded into the microchannels successfully formed monolayers and underwent angiogenic sprouting within 7 days in culture. In summary, the proposed approach is a simple and effective strategy for engineering of pre-vascularized dental pulp constructs offering potentially beneficial translational outcomes.

  3. Microbial transformation of ginsenosides extracted from Panax ginseng adventitious roots in an airlift bioreactor

    OpenAIRE

    Xiaolin Song; Hao Wu; Xuanchun Piao; Zhenhao Yin; Chengri Yin

    2017-01-01

    Background: Ginsenoside is the most important secondary metabolite in ginseng. Natural sources of wild ginseng have been overexploited. Although root culture can reduce the length of the growth cycle of ginseng, the number of species of ginsenosides is reduced and their contents are lower in the adventitious roots of ginseng than in the roots of ginseng cultivated in the field. Results: In this study, 147 strains of β-glucosidase-producing microorganisms were isolated from soil. Of these, ...

  4. Totally optimal decision rules

    KAUST Repository

    Amin, Talha

    2017-11-22

    Optimality of decision rules (patterns) can be measured in many ways. One of these is referred to as length. Length signifies the number of terms in a decision rule and is optimally minimized. Another, coverage represents the width of a rule’s applicability and generality. As such, it is desirable to maximize coverage. A totally optimal decision rule is a decision rule that has the minimum possible length and the maximum possible coverage. This paper presents a method for determining the presence of totally optimal decision rules for “complete” decision tables (representations of total functions in which different variables can have domains of differing values). Depending on the cardinalities of the domains, we can either guarantee for each tuple of values of the function that totally optimal rules exist for each row of the table (as in the case of total Boolean functions where the cardinalities are equal to 2) or, for each row, we can find a tuple of values of the function for which totally optimal rules do not exist for this row.

  5. Totally optimal decision rules

    KAUST Repository

    Amin, Talha M.; Moshkov, Mikhail

    2017-01-01

    Optimality of decision rules (patterns) can be measured in many ways. One of these is referred to as length. Length signifies the number of terms in a decision rule and is optimally minimized. Another, coverage represents the width of a rule’s applicability and generality. As such, it is desirable to maximize coverage. A totally optimal decision rule is a decision rule that has the minimum possible length and the maximum possible coverage. This paper presents a method for determining the presence of totally optimal decision rules for “complete” decision tables (representations of total functions in which different variables can have domains of differing values). Depending on the cardinalities of the domains, we can either guarantee for each tuple of values of the function that totally optimal rules exist for each row of the table (as in the case of total Boolean functions where the cardinalities are equal to 2) or, for each row, we can find a tuple of values of the function for which totally optimal rules do not exist for this row.

  6. Effect of the application of AIA and sucrose in the in vitro rooting of Sonate and Lambada varieties of Anthurium andraeanum Lind.

    Directory of Open Access Journals (Sweden)

    Nydia del Rivero Bautista

    2005-04-01

    Full Text Available The effect of different concentrations of indole-3-acetic acid (AIA and sucrose Anthurium andraeanum in the varieties ‘Lambada’ and ‘Sonate’ in the enraizamiento phase during the micropropagation of this specieswas determined in this study. Nodal explants, coming from plantlets obtained in vitro, were cultivated in a liquid culture mediumMS modified, supplemented with 2.89 and 5.71 μM AIA and 30 and 40 g.l-1 (w/v of sucrose. The length of the buds (cm, the number of roots and the length of the roots (cmwere the evaluated variables . In the rooting phase the best sucrose concentration in the cultivation medium was of 40 g.l-1, being observed that the increment in its concentration improved the length of the plants, as well as the number and length of the roots for the two varieties. There were differences in the requirement of AIA in the evaluated variables in both varieties. Key words: Araceae, in vitro culture, micropropagation Abbreviations: IAA (Indole-3-acetic acid, NAA (naphthalenacetic acid, IBA (Indole-3-butyric acid, Kin (6-furfurylaminopurine

  7. Quality aspects of ex vivo root canal treatments done by undergraduate dental students using four different endodontic treatment systems.

    Science.gov (United States)

    Jungnickel, Luise; Kruse, Casper; Vaeth, Michael; Kirkevang, Lise-Lotte

    2018-04-01

    To evaluate factors associated with treatment quality of ex vivo root canal treatments performed by undergraduate dental students using different endodontic treatment systems. Four students performed root canal treatment on 80 extracted human teeth using four endodontic treatment systems in designated treatment order following a Latin square design. Lateral seal and length of root canal fillings was radiographically assessed; for lateral seal, a graded visual scale was used. Treatment time was measured separately for access preparation, biomechanical root canal preparation, obturation and for the total procedure. Mishaps were registered. An ANOVA mirroring the Latin square design was performed. Use of machine-driven nickel-titanium systems resulted in overall better quality scores for lateral seal than use of the manual stainless-steel system. Among systems with machine-driven files, scores did not significantly differ. Use of machine-driven instruments resulted in shorter treatment time than manual instrumentation. Machine-driven systems with few files achieved shorter treatment times. With increasing number of treatments, root canal-filling quality increased, treatment time decreased; a learning curve was plotted. No root canal shaping file separated. The use of endodontic treatment systems with machine-driven files led to higher quality lateral seal compared to the manual system. The three contemporary machine-driven systems delivered comparable results regarding quality of root canal fillings; they were safe to use and provided a more efficient workflow than the manual technique. Increasing experience had a positive impact on the quality of root canal fillings while treatment time decreased.

  8. Iron- and ferritin-dependent reactive oxygen species distribution: impact on Arabidopsis root system architecture.

    Science.gov (United States)

    Reyt, Guilhem; Boudouf, Soukaina; Boucherez, Jossia; Gaymard, Frédéric; Briat, Jean-Francois

    2015-03-01

    Iron (Fe) homeostasis is integrated with the production of reactive oxygen species (ROS), and distribution at the root tip participates in the control of root growth. Excess Fe increases ferritin abundance, enabling the storage of Fe, which contributes to protection of plants against Fe-induced oxidative stress. AtFer1 and AtFer3 are the two ferritin genes expressed in the meristematic zone, pericycle and endodermis of the Arabidopsis thaliana root, and it is in these regions that we observe Fe stained dots. This staining disappears in the triple fer1-3-4 ferritin mutant. Fe excess decreases primary root length in the same way in wild-type and in fer1-3-4 mutant. In contrast, the Fe-mediated decrease of lateral root (LR) length and density is enhanced in fer1-3-4 plants due to a defect in LR emergence. We observe that this interaction between excess Fe, ferritin, and root system architecture (RSA) is in part mediated by the H2O2/O2·- balance between the root cell proliferation and differentiation zones regulated by the UPB1 transcription factor. Meristem size is also decreased in response to Fe excess in ferritin mutant plants, implicating cell cycle arrest mediated by the ROS-activated SMR5/SMR7 cyclin-dependent kinase inhibitors pathway in the interaction between Fe and RSA. Copyright © 2015 The Author. Published by Elsevier Inc. All rights reserved.

  9. Soil-root Shear Strength Properties of Some Slope Plants

    International Nuclear Information System (INIS)

    Normaniza Osman; Mohamad Nordin Abdullah; Faisal Haji Ali

    2011-01-01

    Rapid development in hilly areas in Malaysia has become a trend that put a stress to the sloping area. It reduces the factor of safety by reducing the resistant force and therefore leads to slope failure. Vegetation plays a big role in reinforcement functions via anchoring the soils and forms a binding network within the soil layer that tied the soil masses together. In this research, three plant species namely Acacia mangium, Dillenia suffruticosa and Leucaena leucocaphala were assessed in term of their soil-root shear strength properties. Our results showed that Acacia mangium had the highest shear strength values, 30.4 kPa and 50.2 kPa at loads 13.3 kPa and 24.3 kPa, respectively. Leucaena leucocaphala showed the highest in cohesion factor, which was almost double the value in those of Dillenia suffruticosa and Acacia mangium. The root profile analysis indicated Dillenia suffruticosa exhibited the highest values in both root length density and root volume, whilst Leucaena leucocaphala had the highest average of root diameter. (author)

  10. Root morphology, hydraulic conductivity and plant water relations of high-yielding rice grown under aerobic conditions.

    Science.gov (United States)

    Kato, Yoichiro; Okami, Midori

    2011-09-01

    Increasing physical water scarcity is a major constraint for irrigated rice (Oryza sativa) production. 'Aerobic rice culture' aims to maximize yield per unit water input by growing plants in aerobic soil without flooding or puddling. The objective was to determine (a) the effect of water management on root morphology and hydraulic conductance, and (b) their roles in plant-water relationships and stomatal conductance in aerobic culture. Root system development, stomatal conductance (g(s)) and leaf water potential (Ψ(leaf)) were monitored in a high-yielding rice cultivar ('Takanari') under flooded and aerobic conditions at two soil moisture levels [nearly saturated (> -10 kPa) and mildly dry (> -30 kPa)] over 2 years. In an ancillary pot experiment, whole-plant hydraulic conductivity (soil-leaf hydraulic conductance; K(pa)) was measured under flooded and aerobic conditions. Adventitious root emergence and lateral root proliferation were restricted even under nearly saturated conditions, resulting in a 72-85 % reduction in total root length under aerobic culture conditions. Because of their reduced rooting size, plants grown under aerobic conditions tended to have lower K(pa) than plants grown under flooded conditions. Ψ(leaf) was always significantly lower in aerobic culture than in flooded culture, while g(s) was unchanged when the soil moisture was at around field capacity. g(s) was inevitably reduced when the soil water potential at 20-cm depth reached -20 kPa. Unstable performance of rice in water-saving cultivations is often associated with reduction in Ψ(leaf). Ψ(leaf) may reduce even if K(pa) is not significantly changed, but the lower Ψ(leaf) would certainly occur in case K(pa) reduces as a result of lower water-uptake capacity under aerobic conditions. Rice performance in aerobic culture might be improved through genetic manipulation that promotes lateral root branching and rhizogenesis as well as deep rooting.

  11. Genetic and Phenotypic Analysis of Lateral Root Development in Arabidopsis thaliana.

    Science.gov (United States)

    Napsucialy-Mendivil, Selene; Dubrovsky, Joseph G

    2018-01-01

    Root system formation to a great extent depends on lateral root (LR) formation. In Arabidopsis thaliana, LRs are initiated within a parent root in pericycle that is an external tissue of the stele. LR initiation takes place in a strictly acropetal pattern, whereas posterior lateral root primordium (LRP) formation is asynchronous. In this chapter, we focus on methods of genetic and phenotypic analysis of LR initiation, LRP morphogenesis, and LR emergence in Arabidopsis. We provide details on how to make cleared root preparations and how to identify the LRP stages. We also pay attention to the categorization of the LRP developmental stages and their variations and to the normalization of the number of LRs and LRPs formed, per length of the primary root, and per number of cells produced within a root. Hormonal misbalances and mutations affect LRP morphogenesis significantly, and the evaluation of LRP abnormalities is addressed as well. Finally, we deal with various molecular markers that can be used for genetic and phenotypic analyses of LR development.

  12. Path analysis suggests phytoene accumulation is the key step limiting the carotenoid pathway in white carrot roots

    Directory of Open Access Journals (Sweden)

    Carlos Antonio Fernandes Santos

    2005-01-01

    Full Text Available Two F2 carrot (Daucus carota L. populations (orange rooted Brasilia x very dark orange rooted High Carotene Mass - HCM cross and the dark orange rooted cultivated variety B493 x white rooted wild carrot Queen Anne's Lace - QAL cross with very unrelated genetic backgrounds were used to investigate intrinsic factors limiting carotenoid accumulation in carrots by applying phenotypic correlation and path analysis to study the relationships between major root carotenes, root color and several other morphological traits. Most of the correlations between traits were close and agreed in sign between the two populations. Root weight had a moderate to highly significant positive correlation with leaf length, root length and top and middle root diameter. Although phenotypic correlations failed to identify the order of the substrates and products in the carotenoid pathway the correct order of substrates and products (phytoene -> zeta-carotene -> lycopene was identified in the causal diagram of beta-carotene for the Brasilia x HCM population. Path analysis of beta-carotene synthesis in the B493 x QAL population suggested that selection for root carotenes had little effect on plant morphological traits. Causal model of beta-carotene and lycopene in the B493 x QAL population suggested that phytoene synthesis is the key step limiting the carotenoid pathway in white carrots. Path analysis, first presented by Sewall Wright to study quantitative traits, appears to be a powerful statistical approach for the identification of key compounds in complex pathways.

  13. Relationship between root growth, temperature and anion uptake

    Energy Technology Data Exchange (ETDEWEB)

    Holobrada, M; Mistrik, I; Kolek, J [Institute of Experimental Biology and Ecology of the Slovak Academy of Sciences, Bratislava (Czechoslovakia)

    1980-01-01

    The uptake and release were studied of /sup 35/S-sulfate ions by whole intact roots of maize seedlings. From the total incorporated sulfur only 20% were released back to the unlabelled culture solution. In correspondence to the physiological and biochemical-structural vertical gradient of the growing differentiating roots, the release of /sup 35/S from the apical root part was much lower than from the differentiated tissues.

  14. Carbon contributions from roots in cotton based rotations

    Science.gov (United States)

    Tan, D. K. Y.; Hulugalle, N. R.

    2012-04-01

    Most research on the decline in soil organic carbon (SOC) stocks in Australian cotton farming systems has focussed on the inputs from above-ground crop residues, with contribution from roots being less studied. This paper aims to outline the contribution of cotton roots and roots of other crops to soil carbon stocks in furrow-irrigated Vertisols in several cotton (Gossypium hirsutum L.)-based rotations. Data was collected from cotton-based rotation systems: cotton monoculture, cotton-vetch (Vicia benghalensis) Roth.), cotton-wheat (Triticum aestivum L.), cotton-wheat-vetch, cotton-corn, corn-corn, cotton-sorghum (Sorghum bicolor L.) and from BollgardTM II (Bt) and non-Bt cotton. Land management systems were permanent beds, with or without standing stubble, and conventional tillage. Root growth in the surface 0.10 m was measured with the core-break method, and that in the 0.10 to 1.0 m depth with a minirhizotron and I-CAP image capture system. These measurements were used to derive root C added to soil through intra-seasonal root death (Clost), C in roots remaining at the end of season (Croot), and total root C added to soil (Ctotal = Croot + Clost). Ctotal in non-Bt cotton (Sicot 80RRF, 0.9 t C/ha/year) was higher than in Bt cotton (Sicot 80RRF, 0.6 t C/ha/year). Overall, Ctotal from cotton roots ranges between 0.5 to 5 t C/ha/year, with Clost contributing 25-70%. Ctotal was greater with vetch than with wheat and was in the order of vetch in cotton-wheat-vetch (5.1 t C/ha/year) > vetch in cotton-vetch (1.9 t C/ha/year) > wheat in cotton-wheat (1.6 t C/ha/year) = wheat in cotton-wheat-vetch (1.7 t C/ha/year). Intra-seasonal root mortality accounted for 12% of total root carbon in vetch and 36% in wheat. Average corn Ctotal with monoculture was 9.3 t/ha and with cotton-corn 5.0 t/ha. Ctotal averaged between both treatments was, thus, of the order of 7.7 t C/ha/year and average Clost 0.04 t/ha/yr. Sorghum roots contributed less carbon with conventional tillage (8.2 t

  15. Fine-Root Production in an Amazon Rain Forest: Deep Roots are an Important Component of Net Primary Productivity

    Science.gov (United States)

    Norby, R.; Cordeiro, A. L.; Oblitas, E.; Valverde-Barrantes, O.; Quesada, C. A.

    2017-12-01

    Fine-root production is a significant component of net primary production (NPP), but it is the most difficult of the major components to measure. Data on fine-root production are especially sparse from tropical forests, and therefore the estimates of tropical forest NPP may not be accurate. Many estimates of fine-root production are based on observations in the top 15 or 30 cm of soil, with the implicit assumption that this approach will capture most of the root distribution. We measured fine-root production in a 30-m tall, old-growth, terra firme rain forest near Manaus, Brazil, which is the site for a free-air CO2 enrichment (FACE) experiment. Ten minirhizotrons were installed at a 45 degree angle to a depth of 1.1 meters; the tubes were installed 2 years before any measurements were made to allow the root systems to recover from disturbance. Images were collected biweekly, and measurements of root length per area of minirhizotron window were scaled up to grams of root per unit land area. Scaling up minirhizotron measurments is problematic, but our estimate of fine-root standing crop in the top 15 cm of soil (281 ± 37 g dry matter m-2) compares well with a direct measurement of fine roots in two nearby 15-cm soil cores (290 ± 37 g m-2). Although the largest fraction of the fine-root standing crop was in the upper soil horizons, 44% of the fine-root mass was deeper than 30 cm, and 17% was deeper than 60 cm. Annual fine-root production was 934 ± 234 g dry matter m-2 (453 ± 113 g C m-2), which was 35% of estimated NPP of the forest stand (1281 g C m-2). A previous estimate of NPP of the forest at this site was smaller (1010 g m-2), but that estimate relied on fine-root production measured elsewhere and only in the top 10 or 30 cm of soil; fine roots accounted for 21% of NPP in that analysis. Extending root observations deeper into the soil will improve estimates of the contribution of fine-root production to NPP, which will in turn improve estimates of ecosystem

  16. Mycorrhizal Glomus spp. vary in their effects on the dynamics and turnover of fine alfalfa (Medicago sativa L.) roots

    International Nuclear Information System (INIS)

    Ren, A.; Waly, N.; Chunhui, M.; Zhang, Q.; Liu, H.; Yang, J.

    2016-01-01

    The distribution of fine roots in the soil profile has important implications related to water and nutrient uptake. The Objective of this study was to compare the effects of different arbuscular mycorrhizal fungi (AMF) on the fine root dynamics of Medicago sativa L. cv. Sanditi. We used minirhizotrons to observe changes in fine root length density (FRLD, mm/cm2) and fine root surface area density (FRSAD, mm2/cm2) during the growing season. Fine root P concentrations and turnover rate were also measured. The colonization rate of fine roots varied depending on the AMF species. Colonization rates were highest when roots were inoculated with Glomus mosseae and lowest when roots were inoculated G. intraradices. Inoculation with AMF significantly increased both FRLD and FRSAD. G. versiforme increased FRLD and FRSAD most, whereas G. mosseae had the least effect. Inoculation with AMF also decreased fine root turnover rates. Inoculation with a mixture of AMF species increased fine root turnover and P concentrations more than inoculation with a single AMF species. Fine root length density increased to a maximum on Aug. 6 and then decreased. In comparison, FRSAD exhibited two peaks during the growing season. Overall, the Results indicated that inoculation with AMF can significantly promote fine root growth and P uptake by alfalfa growing on soil with low P availability. The AMF may preserve fine root function late in the growing season. (author)

  17. New electronic apex locator Romiapex A-15 presented accuracy for working length determination in permanent teeth

    Directory of Open Access Journals (Sweden)

    Etevaldo Matos Maia Filho

    2014-12-01

    Full Text Available Purpose: The present study aims to evaluate, ex vivo, the accuracy of electronic apex locators Root ZX II and Romiapex-15, for working length (WL determination in permanent teeth. Materials and Methods: Fourteen single-rooted teeth (incisors and canines, with their apices fully formed were used. The dental crowns were removed. The anatomic length of the tooth (real measurement was visually determined through the insertion of a size 10 K-file until the tip of the instrument could be observed in the apical foramen under a microscope (20X. Teeth were fixed in a model of resin and adapted into alginate soaked with saline solution, which was used as an  electrical conductor. Using a K-file, root canals were measured electronically using both devices. The results obtained for each apex locator were compared to the real measurements. The accuracy between the devices was statistically analyzed using the Bland-Altman graph, Intraclass Correlation Coefficient (ICC, and Student’s t-test. Results: The mean difference between the measurements using the Root ZX II was 0.277mm greater than the real measurement, while the measurements from the Romiapex-15 were 0.308mm higher on average. The comparison between Root ZX II and Romiapex-15 had no significant difference (p= 0.868. Conclusion: It was concluded that Root ZX II and Romiapex-15 had similar accuracy. Romiapex-15 could be an option for WL determination in permanent teeth.

  18. Profiling Gene Expression in Germinating Brassica Roots.

    Science.gov (United States)

    Park, Myoung Ryoul; Wang, Yi-Hong; Hasenstein, Karl H

    2014-01-01

    Based on previously developed solid-phase gene extraction (SPGE) we examined the mRNA profile in primary roots of Brassica rapa seedlings for highly expressed genes like ACT7 (actin7), TUB (tubulin1), UBQ (ubiquitin), and low expressed GLK (glucokinase) during the first day post-germination. The assessment was based on the mRNA load of the SPGE probe of about 2.1 ng. The number of copies of the investigated genes changed spatially along the length of primary roots. The expression level of all genes differed significantly at each sample position. Among the examined genes ACT7 expression was most even along the root. UBQ was highest at the tip and root-shoot junction (RS). TUB and GLK showed a basipetal gradient. The temporal expression of UBQ was highest in the MZ 9 h after primary root emergence and higher than at any other sample position. Expressions of GLK in EZ and RS increased gradually over time. SPGE extraction is the result of oligo-dT and oligo-dA hybridization and the results illustrate that SPGE can be used for gene expression profiling at high spatial and temporal resolution. SPGE needles can be used within two weeks when stored at 4 °C. Our data indicate that gene expression studies that are based on the entire root miss important differences in gene expression that SPGE is able to resolve for example growth adjustments during gravitropism.

  19. A Rare Case of Apical Root Resorption during Orthodontic Treatment of Patient with Multiple Aplasia.

    Science.gov (United States)

    Agrawal, Chintan M; Mahida, Khyati; Agrawal, Charu C; Bothra, Jitendrakumar; Mashru, Ketan

    2015-07-01

    External apical root resorption is an adverse effect of orthodontic treatment. It reduces the length of root and breaks the integrity of teeth and dental arch. Orthodontics is the only dental specialty that clinically uses the inflammatory process to correct the mal-aligned teeth. Hence, it is necessary to know the risk factors of root resorption and do everything to reduce the rate of root resorption. Hence, all predisposing factors which are systemic as well as local should be considered before treatment begins. This case report describes the incidence of root resorption following orthodontic treatment and the teeth affected in the patient with multiple aplasia.

  20. A young root-specific gene (ArMY2) from horseradish encoding a MYR II myrosinase with kinetic preference for the root-specific glucosinolate gluconasturtiin.

    Science.gov (United States)

    Loebers, Andreas; Müller-Uri, Frieder; Kreis, Wolfgang

    2014-03-01

    The pungent taste of horseradish is caused by isothiocyanates which are released from glucosinolates by myrosinases. These enzymes are encoded by genes belonging to one of two subfamilies, termed MYR I and MYR II, respectively. A MYR II-type myrosinase gene was identified for the first time in horseradish. The gene termed ArMY2 was only expressed in young roots. A full-length cDNA encoding a myrosinase termed ArMy2 was isolated and heterologously expressed in Pichia pastoris. The recombinant His-tagged enzyme was characterized biochemically. Substrate affinity was 5 times higher towards gluconasturtiin than towards sinigrin. Gluconasturtiin was found to be the most abundant glucosinolate in young horseradish roots while sinigrin dominated in storage roots and leaves. This indicates that a specialized glucosinolate-myrosinase defense system might be active in young roots. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Dynamics of adventitious rooting in mini-cuttings of Eucalyptus benthamii x Eucalyptus dunnii=Dinamica de enraizamento adventício em miniestacas de Eucalyptus benthamii x Eucalyptus dunnii

    Directory of Open Access Journals (Sweden)

    Antônio Natal Gonçalves

    2012-04-01

    Full Text Available It is possible to determine the optimum time for permanence of vegetative propagules (mini-cuttings inside a greenhouse for rooting, and this value can be used to optimize the structure of the nursery. The aim of this study was to determine the dynamics of adventitious rooting in mini-cuttings of three clones of Eucalyptus benthamii x Eucalyptus dunnii. Sprouts of H12, H19 and H20 clones were collected from mini-stumps that were planted in gutters containing sand and grown in a semi-hydroponic system. The basal region of the mini-cuttings was immersed in 2,000 mg L-1 indole-3-butyric acid (IBA solution for 10 seconds. The rooting percentage of the mini-cuttings, the total length of the root system and the rooting rate per mini-cutting were also evaluated at 0 (time of planting, 7, 14, 21, 28, 35, 42, 49 and 56 days. We used logistic and exponential regression to mathematically model the speed of rhizogenesis. The rooting percentage was best represented as a logistic model, and the total length of the root system was best represented as an exponential model. The clones had different speeds of adventitious rooting. The optimum time for permanence of the mini-cuttings inside the greenhouse for rooting was between 35 and 42 days, and varied depending on the genetic material.O tempo ideal de permanência de propágulos vegetativos (miniestacas no interior da casa de vegetação para a rizogênese é possível de ser determinado matematicamente, o que pode otimizar as instalações do viveiro. O objetivo deste estudo foi determinar a dinâmica de enraizamento de miniestacas de três clones de Eucalyptus benthamii x Eucalyptus dunnii. Brotações dos clones H19, H12 e H20 foram coletadas de minicepas plantadas em canaletão com areia e cultivadas sob sistema semi-hidropônico. A região basal da miniestaca foi imersa em solução de 2.000 mg L-1 de ácido indolbutírico (AIB por 10 segundos. A porcentagem de enraizamento de miniestacas, o comprimento

  2. Six-Year Nitrogen–Water Interaction Shifts the Frequency Distribution and Size Inequality of the First-Order Roots of Fraxinus mandschurica in a Mixed Mature Pinus koraiensis Forest

    Science.gov (United States)

    Wang, Cunguo; Geng, Zhenzhen; Chen, Zhao; Li, Jiandong; Guo, Wei; Zhao, Tian-Hong; Cao, Ying; Shen, Si; Jin, Daming; Li, Mai-He

    2017-01-01

    The variation in fine root traits in terms of size inequality at the individual root level can be identified as a strategy for adapting to the drastic changes in soil water and nutrient availabilities. The Gini and Lorenz asymmetry coefficients have been applied to describe the overall degree of size inequality, which, however, are neglected when conventional statistical means are calculated. Here, we used the Gini coefficient, Lorenz asymmetry coefficient and statistical mean in an investigation of Fraxinus mandschurica roots in a mixed mature Pinus koraiensis forest on Changbai Mountain, China. We analyzed 967 individual roots to determine the responses of length, diameter and area of the first-order roots and of branching intensity to 6 years of nitrogen addition (N), rainfall reduction (W) and their combination (NW). We found that first-order roots had a significantly greater average length and area but had smaller Gini coefficients in NW plots compared to in control plots (CK). Furthermore, the relationship between first-order root length and branching intensity was negative in CK, N, and W plots but positive in NW plots. The Lorenz asymmetry coefficient was >1 for the first-order root diameter in NW and W plots as well as for branching intensity in N plots. The bimodal frequency distribution of the first-order root length in NW plots differed clearly from the unimodal one in CK, N, and W plots. These results demonstrate that not only the mean but also the variation and the distribution mode of the first-order roots of F. mandschurica respond to soil nitrogen and water availability. The changes in size inequality of the first-order root traits suggest that Gini and Lorenz asymmetry coefficients can serve as informative parameters in ecological investigations of roots to improve our ability to predict how trees will respond to a changing climate at the individual root level. PMID:29018474

  3. Six-Year Nitrogen-Water Interaction Shifts the Frequency Distribution and Size Inequality of the First-Order Roots of Fraxinus mandschurica in a Mixed Mature Pinus koraiensis Forest.

    Science.gov (United States)

    Wang, Cunguo; Geng, Zhenzhen; Chen, Zhao; Li, Jiandong; Guo, Wei; Zhao, Tian-Hong; Cao, Ying; Shen, Si; Jin, Daming; Li, Mai-He

    2017-01-01

    The variation in fine root traits in terms of size inequality at the individual root level can be identified as a strategy for adapting to the drastic changes in soil water and nutrient availabilities. The Gini and Lorenz asymmetry coefficients have been applied to describe the overall degree of size inequality, which, however, are neglected when conventional statistical means are calculated. Here, we used the Gini coefficient, Lorenz asymmetry coefficient and statistical mean in an investigation of Fraxinus mandschurica roots in a mixed mature Pinus koraiensis forest on Changbai Mountain, China. We analyzed 967 individual roots to determine the responses of length, diameter and area of the first-order roots and of branching intensity to 6 years of nitrogen addition (N), rainfall reduction (W) and their combination (NW). We found that first-order roots had a significantly greater average length and area but had smaller Gini coefficients in NW plots compared to in control plots (CK). Furthermore, the relationship between first-order root length and branching intensity was negative in CK, N, and W plots but positive in NW plots. The Lorenz asymmetry coefficient was >1 for the first-order root diameter in NW and W plots as well as for branching intensity in N plots. The bimodal frequency distribution of the first-order root length in NW plots differed clearly from the unimodal one in CK, N, and W plots. These results demonstrate that not only the mean but also the variation and the distribution mode of the first-order roots of F. mandschurica respond to soil nitrogen and water availability. The changes in size inequality of the first-order root traits suggest that Gini and Lorenz asymmetry coefficients can serve as informative parameters in ecological investigations of roots to improve our ability to predict how trees will respond to a changing climate at the individual root level.

  4. Phosphate-dependent root system architecture responses to salt stress

    KAUST Repository

    Kawa, Dorota; Julkowska, Magdalena; Montero Sommerfeld, Hector; Horst, Anneliek ter; Haring, Michel A; Testerink, Christa

    2016-01-01

    Nutrient availability and salinity of the soil affect growth and development of plant roots. Here, we describe how phosphate availability affects root system architecture (RSA) of Arabidopsis and how phosphate levels modulate responses of the root to salt stress. Phosphate (Pi) starvation reduced main root length and increased the number of lateral roots of Arabidopsis Col-0 seedlings. In combination with salt, low Pi dampened the inhibiting effect of mild salt stress (75mM) on all measured RSA components. At higher NaCl concentrations, the Pi deprivation response prevailed over the salt stress only for lateral root elongation. The Pi deprivation response of lateral roots appeared to be oppositely affected by abscisic acid (ABA) signaling compared to the salt stress response. Natural variation in the response to the combination treatment of salt and Pi starvation within 330 Arabidopsis accessions could be grouped into four response patterns. When exposed to double stress, in general lateral roots prioritized responses to salt, while the effect on main root traits was additive. Interestingly, these patterns were not identical for all accessions studied and multiple strategies to integrate the signals from Pi deprivation and salinity were identified. By Genome Wide Association Mapping (GWAS) 13 genomic loci were identified as putative factors integrating responses to salt stress and Pi starvation. From our experiments, we conclude that Pi starvation interferes with salt responses mainly at the level of lateral roots and that large natural variation exists in the available genetic repertoire of accessions to handle the combination of stresses.

  5. Phosphate-dependent root system architecture responses to salt stress

    KAUST Repository

    Kawa, Dorota

    2016-05-20

    Nutrient availability and salinity of the soil affect growth and development of plant roots. Here, we describe how phosphate availability affects root system architecture (RSA) of Arabidopsis and how phosphate levels modulate responses of the root to salt stress. Phosphate (Pi) starvation reduced main root length and increased the number of lateral roots of Arabidopsis Col-0 seedlings. In combination with salt, low Pi dampened the inhibiting effect of mild salt stress (75mM) on all measured RSA components. At higher NaCl concentrations, the Pi deprivation response prevailed over the salt stress only for lateral root elongation. The Pi deprivation response of lateral roots appeared to be oppositely affected by abscisic acid (ABA) signaling compared to the salt stress response. Natural variation in the response to the combination treatment of salt and Pi starvation within 330 Arabidopsis accessions could be grouped into four response patterns. When exposed to double stress, in general lateral roots prioritized responses to salt, while the effect on main root traits was additive. Interestingly, these patterns were not identical for all accessions studied and multiple strategies to integrate the signals from Pi deprivation and salinity were identified. By Genome Wide Association Mapping (GWAS) 13 genomic loci were identified as putative factors integrating responses to salt stress and Pi starvation. From our experiments, we conclude that Pi starvation interferes with salt responses mainly at the level of lateral roots and that large natural variation exists in the available genetic repertoire of accessions to handle the combination of stresses.

  6. Relação entre o tempo de enraizamento in vitro e o crescimento de plantas de bananeira na aclimatização Relationship between the in vitro rooting time and the growth of banana plants in the aclimatization

    Directory of Open Access Journals (Sweden)

    Frederico Henrique da Silva Costa

    2008-03-01

    buds obtained from the in vitro establishment and multiplication of stem apices of Caipira (AAA, Preciosa (AAAB and Japira (AAAB cultivars were used. The MS medium with reduction to 50% of the salt concentration adding 30 g.L-1 of sucrose, 1 mg.L-1 of IBA, and 6 g.L-1 of agar was used to induce rooting. The treatments were analyzed in a 3x4 factorial design, with three cultivars (Caipira, Preciosa and Japira and four in vitro rooting periods (7, 14, 21 and 28 days, given a total of 12 treatments. At the end of each period, the height of the aerial portion, and number and length of roots were assessed, and the plants were submitted to 90 days of acclimatization. After that, the survival, number and length of roots, pseudostem diameter, and dry weight of the roots, aerial and total portions of the plants were assessed. Generally, the root induction step in the in vitro banana budding occurred up to 14 days of cultivation in rooting medium, and after that, the roots grew only in length. Among the cultivars, it was verified that, with the exception of the pseudostem diameter, the Caipira cultivar showed superior in vitro vegetative growth, and during the acclimatization, the height of the plant, number and length of the roots, and dry mass of the aerial, roots, and total parts, were also superior to the observed in Preciosa and Japira cultivars. After 21 days on rooting medium, the survival rate of the plants in greenhouse reach 100%, in despite of the tested cultivar.

  7. Sheared-root inocula of vesicular-arbuscular mycorrhizal fungi.

    Science.gov (United States)

    Sylvia, D M; Jarstfer, A G

    1992-01-01

    For efficient handling, vesicular-arbuscular mycorrhizal fungi should be processed into small and uniform inocula; however, processing can reduce the inoculum density. In this article we describe the preparation and use of sheared-root inocula of Glomus spp. in which inoculum densities were increased during processing. Our objectives were to determine inoculum viability and density after shearing and to ascertain if the sheared inocula could be pelletized or used with a gel carrier. Root samples were harvested from aeroponic cultures, blotted dry, cut into 1-cm lengths, and sheared in a food processor for up to 80 s. After shearing, the inoculum was washed over sieves, and the propagule density in each fraction was determined. Sheared inocula were also encapsulated in carrageenan or used in a gel carrier. Shearing aeroponically produced root inocula reduced particle size. Propagule density increased with decreasing size fraction down to a size of 63 mum, after which propagule density decreased. The weighted-average propagule density of the inoculum was 135,380 propagules g (dry weight) of sheared root material. Sheared roots were encapsulated successfully in carrageenan, and the gel served as an effective carrier. Aeroponic root inoculum was stored dry at 4 degrees C for 23 months without significant reduction in propagule density; however, this material was not appropriate for shearing. Moist roots, useful for shearing, began to lose propagule density after 1 month of storage. Shearing proved to be an excellent method to prepare viable root inocula of small and uniform size, allowing for more efficient and effective use of limited inoculum supplies.

  8. Transcriptional sequencing and analysis of major genes involved in the adventitious root formation of mango cotyledon segments.

    Science.gov (United States)

    Li, Yun-He; Zhang, Hong-Na; Wu, Qing-Song; Muday, Gloria K

    2017-06-01

    A total of 74,745 unigenes were generated and 1975 DEGs were identified. Candidate genes that may be involved in the adventitious root formation of mango cotyledon segment were revealed. Adventitious root formation is a crucial step in plant vegetative propagation, but the molecular mechanism of adventitious root formation remains unclear. Adventitious roots formed only at the proximal cut surface (PCS) of mango cotyledon segments, whereas no roots were formed on the opposite, distal cut surface (DCS). To identify the transcript abundance changes linked to adventitious root development, RNA was isolated from PCS and DCS at 0, 4 and 7 days after culture, respectively. Illumina sequencing of libraries generated from these samples yielded 62.36 Gb high-quality reads that were assembled into 74,745 unigenes with an average sequence length of 807 base pairs, and 33,252 of the assembled unigenes at least had homologs in one of the public databases. Comparative analysis of these transcriptome databases revealed that between the different time points at PCS there were 1966 differentially expressed genes (DEGs), while there were only 51 DEGs for the PCS vs. DCS when time-matched samples were compared. Of these DEGs, 1636 were assigned to gene ontology (GO) classes, the majority of that was involved in cellular processes, metabolic processes and single-organism processes. Candidate genes that may be involved in the adventitious root formation of mango cotyledon segment are predicted to encode polar auxin transport carriers, auxin-regulated proteins, cell wall remodeling enzymes and ethylene-related proteins. In order to validate RNA-sequencing results, we further analyzed the expression profiles of 20 genes by quantitative real-time PCR. This study expands the transcriptome information for Mangifera indica and identifies candidate genes involved in adventitious root formation in cotyledon segments of mango.

  9. Preparation of severely curved simulated root canals using engine-driven rotary and conventional hand instruments.

    Science.gov (United States)

    Szep, S; Gerhardt, T; Leitzbach, C; Lüder, W; Heidemann, D

    2001-03-01

    This in vitro study evaluated the efficacy and safety of six different nickel-titanium engine-driven instruments used with a torque-controlled engine device and nickel-titanium hand and stainless steel hand instruments in preparation of curved canals. A total of 80 curved (36 degrees) simulated root canals were prepared. Images before and after were superimposed, and instrumentation areas were observed. Time of instrumentation, instrument failure, change in working length and weight loss were also recorded. Results show that stainless steel hand instruments cause significantly less transportation towards the inner wall of the canal than do nickel-titanium hand instruments. No instrument fracture occurred with hand instruments, but 30-60% breakage of instruments was recorded during instrumentation with the engine-driven devices. The working length was maintained by all types of instruments. Newly developed nickel-titanium rotary files were not able to prevent straightening of the severely curved canals when a torque-controlled engine-driven device was used.

  10. The total body length and body weight examination among gabus Sentani fish population, Oxyeleotris heterodon, Weber 1907 (Pisces: Eleotridae) of Sentani lake, Papua, Indonesia

    Science.gov (United States)

    Sriyani, E. D.; Abinawanto, Bowolaksono, A.

    2017-07-01

    The gabus Sentani fish lived in the Sentani Lake, Papua, since million years ago. Nowadays, the population of those species is getting extinct because of the overexploitation, whereas the culture effort of this species has not been developed, yet. The purpose of the study was to examine the total body length and body weight collected from some villages surrounding Sentani Lake such as Ifar village, Sosiri village, and Putali village. The body weight average of gabus fish from Ifar village, Sosiri village, and Putali village were 373.53 g, 426.86 g, and 118.34 g respectively. While the total body length average of gabus Sentani fish from Ifar village, Sosiri village, and Putali village were 279.30 mm, 223.30 mm and 222.06 mm, respectively. The growth model was W = 0.021067L3.086 with R2 value was 35.8 %, and r value was 0.598. Gabus Sentani fish, Oxyeleotris heterodon (Weber 1907) exhibited positive allometric (b > 3).

  11. [Effects of Ca2+ on nitric oxide-induced adventitious rooting in cucumber under drought stress].

    Science.gov (United States)

    Li, Chun Lan; Niu, Li Juan; Hu, Lin Li; Liao, Wei Biao; Chen, Yue

    2017-11-01

    Cucumber (Cucumis sativus L. 'Xinchun 4') was used to explore the relationship between nitric oxide (NO) and calcium (Ca 2+ ) during adventitious rooting under drought stress. Rooting parameters, endogenous Ca 2+ fluorescent intensity and the antioxidant enzymes activity (SOD, CAT and APX) in cucumber explants under drought stress were investigated. The results showed that treatment with 200 μmol·L -1 CaCl 2 and 0.05% PEG significantly improved the number and length of adventitious root in cucumber explants under drought stress, while the application of Ca 2+ chelating agent (EGTA) and channel inhibitor (BAPTA/AM) significantly decreased NO-induced number and length of adventitious root under drought stress. Under drought stress, the fluorescence intensity of Ca 2+ in hypocotyls treated with NO and CaCl 2 was improved, however, the Ca 2+ fluorescence intensity in the hypocotyls treated with NO scavenger (cPTIO) was significantly lower than that in the hypocotyls treated with NO. Under drought stress, the activities of antioxidant enzymes in the cucumber explants were significantly promoted by the treatments with NO and CaCl 2 , however, Ca 2+ chelating agent and channel inhibitor significantly decreased the activity of antioxidant enzymes induced by NO. In conclusion, Ca 2+ might be involved in the process of NO-adjusted antioxidant enzymes activity during adventitious rooting under drought stress, which alleviated the negative effects of drought on the adventitious rooting and promoted the formation of adventitious roots.

  12. Colonization of Plant Growth Promoting Rhizobacteria (PGPR) on Two Different Root Systems

    International Nuclear Information System (INIS)

    Chaudhry, M. Z.; Naz, A. U.; Nawaz, A.; Nawaz, A.; Mukhtar, H.

    2016-01-01

    Phytohormones producing bacteria enhance the plants growth by positively affecting growth of the root. Plant growth promoting bacteria (PGPR) must colonize the plant roots to contribute to the plant's endogenous pool of phytohormones. Colonization of these plant growth promoting rhizobacteria isolated from rhizosplane and soil of different crops was evaluated on different root types to establish if the mechanism of host specificity exist. The bacteria were isolated from maize, wheat, rice, canola and cotton and phytohormone production was detected and quantified by HPLC. Bacteria were inoculated on surface sterilized seeds of different crops and seeds were germinated. After 7 days the bacteria were re-isolated from the roots and the effect of these bacteria was observed by measuring increase in root length. Bacteria isolated from one plant family (monocots) having fibrous root performed well on similar root system and failed to give significant results on other roots (tap root) of dicots. Some aggressive strains were able to colonize both root systems. The plant growth promoting activities of the bacteria were optimum on the same plant from whom roots they were isolated. The results suggest that bacteria adapt to the root they naturally inhabit and colonize the same plant root systems preferably. Although the observe trend indicate host specificity but some bacteria were aggressive colonizers which grew on all the plants used in experiment. (author)

  13. Fine-tuning by strigolactones of root response to low phosphate.

    Science.gov (United States)

    Kapulnik, Yoram; Koltai, Hinanit

    2016-03-01

    Strigolactones are plant hormones that regulate the development of different plant parts. In the shoot, they regulate axillary bud outgrowth and in the root, root architecture and root-hair length and density. Strigolactones are also involved with communication in the rhizosphere, including enhancement of hyphal branching of arbuscular mycorrhizal fungi. Here we present the role and activity of strigolactones under conditions of phosphate deprivation. Under these conditions, their levels of biosynthesis and exudation increase, leading to changes in shoot and root development. At least for the latter, these changes are likely to be associated with alterations in auxin transport and sensitivity. On the other hand, strigolactones may positively affect plant-mycorrhiza interactions and thereby promote phosphate acquisition by the plant. Strigolactones may be a way for plants to fine-tune their growth pattern under phosphate deprivation. © 2015 Institute of Botany, Chinese Academy of Sciences.

  14. Bending and Shear Stresses Developed by the Instantaneous Arrest of the Root of a Moving Cantilever Beam

    Science.gov (United States)

    Stowell, Elbridge, Z; Schwartz, Edward B; Houbolt, John C

    1945-01-01

    A theoretical and experimental investigation has been made of the behavior of a cantilever beam in transverse motion when its root is suddenly brought to rest. Equations are given for determining the stresses, the deflections, and the accelerations that arise in the beam as a result of the impact. The theoretical equations, which have been confirmed experimentally, reveal that, at a given percentage of the distance from root to tip, the bending stresses for a particular mode are independent of the length of the beam, whereas the shear stresses vary inversely with the length.

  15. Rooting of hybrid clones of Populus tremula L. x P. tremuloides Michx. by stem cuttings derived from micropropagated plants

    Energy Technology Data Exchange (ETDEWEB)

    Qibin Yu [Univ. of Helsinki (Finland). Dept. of Plant Biology; Maentylae, N. [Univ. of Turku (Finland). Dept. of Biology, Plant Physiology and Molecular Biology; Salonen, M. [Finnish Forest Research Inst., Laeyliaeinen (Finland). Haapastensyrjae Breeding Station

    2001-07-01

    Propagation costs could be cut by replacing part of the micropropagation process with steps involving more traditional techniques. This study explored possibilities for improving existing vegetative propagation techniques for aspen using stem cuttings obtained from micropropagated plants. Vegetative propagation through stem cuttings was studied in 10 micropropagated hybrid aspen clones (Populus tremula L. x P. tremuloides Michx). Cuttings containing one axillary bud were harvested from the same donor plants twice during the growing season: the first harvest in May and the second harvest in July. Rooting percentage was correlated positively with root length, number of roots and height of cutting plant but negatively with length of rooting. The average rooting percentage was 53% in the first harvest and 27% in second harvest. Indole-3-butyric acid treatments (1.2 mM) significantly improved rooting in the second harvest, but not in the first harvest, suggesting different endogenous auxin levels in the cuttings. A significant variation for most traits related to rooting ability was found among the clones, indicating that clonal effects play an important role in the propagation of aspen. Thus, clones with a good response in shoot growth and rooting could be exploited in large-scale propagation using stem cuttings.

  16. Quantitative imaging of radial oxygen loss from Valisneria spiralis roots with a fluorescent planar optode

    Energy Technology Data Exchange (ETDEWEB)

    Han, Chao [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008 (China); Ren, Jinghua [Geological Survey of Jiangsu Province, Nanjing 210018 (China); Tang, Hao [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008 (China); Xu, Di, E-mail: dxu@niglas.ac.cn [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008 (China); Xie, Xianchuan, E-mail: xchxie@nju.edu.cn [State Key Laboratory of Pollution Control and Resource Reuse, Center for Hydroscience Research, School of the Environment, Nanjing University, Nanjing 210093 (China)

    2016-11-01

    Oxygen (O{sub 2}) availability within the sediment–root interface is critical to the survival of macrophytes in O{sub 2}-deficient sediment; however, our knowledge of the fine-scale impact of macrophyte roots upon the spatiotemporal dynamics of O{sub 2} is relatively limited. In this study, a non-invasive imaging technology was utilized to map O{sub 2} micro-distribution around Vallisneria spiralis. Long-term imaging results gathered during a 36 day-period revealed an abundance of O{sub 2} spatiotemporal patterns ranging from 0 to 250 μmol L{sup −} {sup 1}. The root-induced O{sub 2} leakage and consequent oxygenated area were stronger in the vicinity of the basal root compared to that found in the root tip. The O{sub 2} images revealed V. spiralis exhibited radial O{sub 2} loss (ROL) along the entire root, and the O{sub 2} distribution along the root length showed a high degree of small-scale spatial heterogeneity decreasing from 80% at the basal root surface to 10% at the root tip. The oxygenated zone area around the roots increased as O{sub 2} levels increased with root growth and irradiance intensities ranging from 0 to 216 μmol photons m{sup −} {sup 2} s{sup −} {sup 1}. A weak ROL measuring < 20% air saturation around the basal root surface was maintained in darkness, which was presumably attributed to the O{sub 2} supply from overlying water via plant aerenchyma. The estimated total O{sub 2} release to the rhizosphere of V. spiralis was determined to range from 8.80 ± 7.32 to 30.34 ± 17.71 nmol m{sup −} {sup 2} s{sup −} {sup 1}, which is much higher than many other macrophyte species. This O{sub 2} release may be an important contribution to the high-capacity of V. spiralis for quickly colonizing anaerobic sediment. - Highlights: • Planar imaging method was used to map O2 micro-distribution. • Highly dynamic rhizospheric O2-spatiotemporal distribution was observed. • O{sub 2} leakage along the entire root of Vallisneria spirals were

  17. Comparison of positive-pressure, passive ultrasonic, and laser-activated irrigations on smear-layer removal from the root canal surface.

    Science.gov (United States)

    Sahar-Helft, Sharonit; Sarp, Ayşe Sena Kabaş; Stabholtz, Adam; Gutkin, Vitaly; Redenski, Idan; Steinberg, Doron

    2015-03-01

    The purpose of this study was to compare the efficacy of three irrigation techniques for smear-layer removal with 17% EDTA. Cleaning and shaping the root canal system during endodontic treatment produces a smear layer and hard tissue debris. Three irrigation techniques were tested for solution infiltration of this layer: positive-pressure irrigation, passive ultrasonic irrigation, and laser-activated irrigation. Sixty extracted teeth were divided into six equal groups; 17% EDTA was used for 60 sec irrigation of five of the groups. The groups were as follows: Group 1, treated only with ProTaper™ F3 Ni-Ti files; Group 2, positive-pressure irrigation, with a syringe; Group 3, passive ultrasonic irrigation, inserted 1 mm short of the working length; Group 4, passive ultrasonic irrigation, inserted in the upper coronal third of the root; Group 5, Er:YAG laser-activated irrigation, inserted 1 mm short of the working length; and Group 6, Er:YAG laser-activated irrigation, inserted in the upper coronal third of the root. Scanning electron microscopy showed that the smear layer is removed most efficiently using laser-activated irrigation at low energy with 17% EDTA, inserted either at the working length or only in the coronal upper third of the root. Amounts of Ca, P, and O were not significantly different on all treated dentin surfaces. Smear-layer removal was most effective when the root canals were irrigated using Er:YAG laser at low energy with 17% EDTA solution. Interestingly, removal of the smear layer along the entire canal was similar when the laser was inserted in the upper coronal third and at 1 mm short of the working length of the root canal. This effect was not observed with the ultrasonic and positive-pressure techniques.

  18. The initiation of lateral roots in the primary roots of maize (Zea mays L.) implies a reactivation of cell proliferation in a group of founder pericycle cells.

    Science.gov (United States)

    Alarcón, M Victoria; Lloret, Pedro G; Martín-Partido, Gervasio; Salguero, Julio

    2016-03-15

    The initiation of lateral roots (LRs) has generally been viewed as a reactivation of proliferative activity in pericycle cells that are committed to initiate primordia. However, it is also possible that pericycle founder cells that initiate LRs never cease proliferative activity but rather are displaced to the most distal root zones while undertaking successive stages of LR initiation. In this study, we tested these two alternative hypotheses by examining the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into the DNA of meristematic root cells of Zea mays. According to the values for the length of the cell cycle and values for cell displacement along the maize root, our results strongly suggest that pericycle cells that initiate LR primordia ceased proliferative activity upon exiting the meristematic zone. This finding is supported by the existence of a root zone between 4 and 20mm from the root cap junction, in which neither mitotic cells nor labelled nuclei were observed in phloem pericycle cells. Copyright © 2016 Elsevier GmbH. All rights reserved.

  19. The relationship between root growth, temperature and anion uptake

    International Nuclear Information System (INIS)

    Holobrada, M.; Mistrik, I.; Kolek, J.

    1980-01-01

    The uptake and release were studied of 35 S-sulfate ions by whole intact roots of maize seedlings. From the total incorporated sulfur only 20% were released back to the unlabelled culture solution. In correspondence to the physiological and biochemical-structural vertical gradient of the growing differentiating roots, the release of 35 S from the apical root part was much lower than from the differentiated tissues. (author)

  20. The inflow of Cs-137 in soil with root litter and root exudates of Scots pine

    Science.gov (United States)

    Shcheglov, Alexey; Tsvetnova, Olga; Popova, Evgenia

    2017-04-01

    In the model experiment on evaluation of Cs-137 inflow in the soil with litter of roots and woody plants root exudates on the example of soil and water cultures of Scots pine (Pinus sylvestris L.) was shown, that through 45 days after the deposit Cs-137 solution on pine needles (specific activity of solution was 3.718*106 Bk) of the radionuclide in all components of model systems has increased significantly: needles, small branches and trunk by Cs-137 surface contamination during the experiment; roots as a result of the internal distribution of the radionuclide in the plant; soil and soil solution due to the of receipt Cs-137 in the composition of root exudates and root litter. Over 99% of the total reserve of Cs-137 accumulated in the components of the soil and water systems, accounted for bodies subjected to external pollution (needles and small branches) and soil solution, haven't been subjected to surface contamination. At the same contamination of soil and soil solution by Cs-137 in the model experiment more than a> 99.9% was due to root exudates

  1. De novo transcriptome analysis of pneumatophores (modified roots in the true mangrove species Avicennia marina and identification of the genes related to root gas exchange

    Directory of Open Access Journals (Sweden)

    Purushothaman Natarajan

    2017-10-01

    Full Text Available Mangroves plants which grow in estuaries naturally tolerate extreme conditions of high salinity (90 ppt and high light intensity. Avicennia marina is a true mangrove tree species with physiological adaptations like modified root system (pneumatophores and salt excretion glands in leaves as its one of the unique features to consider. The pneumatophores are a special type of roots with negative geotropism that project above the water surface or the level of flooded soils [1]. In contact with air these roots develop lenticels, which improve gas exchange between roots and environment [2]. In swamps and wetlands the presence of pneumatophores facilitates oxygen diffusion through the tissues, maintaining levels adequate for cellular respiration [3]. Objective of this study was to perform the whole transcriptome analysis of pneumatophore tissue of A. marina by Illumina sequencing and to identify putative genes involved in process of root gas exchange. We generated 19.73 million of paired-end reads and assembled into 86,856 unigenes with an average length of 772 bp. Further, annotation, tissue specific gene expression and genes related to root gas exchange will be presented.

  2. Review of root canal irrigant delivery techniques and devices

    Directory of Open Access Journals (Sweden)

    Yeon-Jee Yoo

    2011-05-01

    Full Text Available Introduction Eliminating the residual debris and bacteria in the root canal system is one of the main purposes of the endodontic treatment. However, the complexity on the anatomy of the root canal system makes it difficult to eliminate the bacterial biofilm existing along the root canal surface and necrotic pulp tissue by mechanical instrumentation and chemical irrigation. Recently, more effective irrigant delivery systems for root canal irrigation have been developed. The purpose of this review was to present an overview of root canal irrigant delivery techniques and devices available in endodontics. Review The contents of this paper include as follows; - syringe-needle irrigation, manual dynamic irrigation, brushes - sonic and ultrasonic irrigation, passive ultrasonic irrigation, rotary brush, RinsEndo, EndoVac, Laser Conclusion Though technological advances during the last decade have brought to fruition new agitation devices that rely on various mechanisms, there are few evidence based study to correlate the clinical efficacy of these devices with improved outcomes except syringe irrigation with needle and ultrasonic irrigation. The clinicians should try their best efforts to deliver antimicrobial and tissue solvent solutions in predictable volumes safely to working length.

  3. Acclimation of fine root respiration to soil warming involves starch deposition in very fine and fine roots: a case study in Fagus sylvatica saplings.

    Science.gov (United States)

    Di Iorio, Antonino; Giacomuzzi, Valentino; Chiatante, Donato

    2016-03-01

    Root activities in terms of respiration and non-structural carbohydrates (NSC) storage and mobilization have been suggested as major physiological roles in fine root lifespan. As more frequent heat waves and drought periods within the next decades are expected, to what extent does thermal acclimation in fine roots represent a mechanism to cope with such upcoming climatic conditions? In this study, the possible changes in very fine (diameter respiration rate and NSC [soluble sugars (SS) and starch] concentrations, were investigated on 2-year-old Fagus sylvatica saplings subjected to a simulated long-lasting heat wave event and to co-occurring soil drying. For both very fine and fine roots, soil temperature (ST) resulted inversely correlated with specific root length, respiration rates and SSs concentration, but directly correlated with root mass, root tissue density and starch concentration. In particular, starch concentration increased under 28 °C for successively decreasing under 21 °C ST. These findings showed that thermal acclimation in very fine and fine roots due to 24 days exposure to high ST (∼ 28 °C), induced starch accumulation. Such 'carbon-savings strategy' should bear the maintenance costs associated to the recovery process in case of restored favorable environmental conditions, such as those occurring at the end of a heat wave event. Drought condition seems to affect the fine root vitality much more under moderate than high temperature condition, making the temporary exposure to high ST less threatening to root vitality than expected. © 2015 Scandinavian Plant Physiology Society.

  4. Unearthing the hidden world of roots: Root biomass and architecture differ among species within the same guild.

    Directory of Open Access Journals (Sweden)

    Katherine Sinacore

    Full Text Available The potential benefits of planting trees have generated significant interest with respect to sequestering carbon and restoring other forest based ecosystem services. Reliable estimates of carbon stocks are pivotal for understanding the global carbon balance and for promoting initiatives to mitigate CO2 emissions through forest management. There are numerous studies employing allometric regression models that convert inventory into aboveground biomass (AGB and carbon (C. Yet the majority of allometric regression models do not consider the root system nor do these equations provide detail on the architecture and shape of different species. The root system is a vital piece toward understanding the hidden form and function roots play in carbon accumulation, nutrient and plant water uptake, and groundwater infiltration. Work that estimates C in forests as well as models that are used to better understand the hydrologic function of trees need better characterization of tree roots. We harvested 40 trees of six different species, including their roots down to 2 mm in diameter and created species-specific and multi-species models to calculate aboveground (AGB, coarse root belowground biomass (BGB, and total biomass (TB. We also explore the relationship between crown structure and root structure. We found that BGB contributes ~27.6% of a tree's TB, lateral roots extend over 1.25 times the distance of crown extent, root allocation patterns varied among species, and that AGB is a strong predictor of TB. These findings highlight the potential importance of including the root system in C estimates and lend important insights into the function roots play in water cycling.

  5. Apical root resorption during orthodontic treatment. A prospective study using cone beam CT.

    Science.gov (United States)

    Lund, Henrik; Gröndahl, Kerstin; Hansen, Ken; Gröndahl, Hans-Göran

    2012-05-01

    To investigate the incidence and severity of root resorption during orthodontic treatment by means of cone beam computed tomography (CBCT) and to explore factors affecting orthodontically induced inflammatory root resorption (OIIRR). CBCT examinations were performed on 152 patients with Class I malocclusion. All roots from incisors to first molars were assessed on two or three occasions. At treatment end, 94% of patients had ≥1 root with shortening >1 mm, and 6.6% had ≥1 tooth where it exceeded 4 mm. Among teeth, 56.3% of upper lateral incisors had root shortening >1 mm. Of upper incisors and the palatal root of upper premolars, 2.6% showed root shortenings >4 mm. Slanted surface resorptions of buccal and palatal surfaces were found in 15.1% of upper central and 11.5% of lateral incisors. Monthly root shortening was greater after 6-month control than before. Upper jaw teeth and anterior teeth were significantly associated with the degree of root shortening. Gender, root length at baseline, and treatment duration were not. Practically all patients and up to 91% of all teeth showed some degree of root shortening, but few patients and teeth had root shortenings >4 mm. Slanted root resorption was found on root surfaces that could be evaluated only by a tomographic technique. A CBCT technique can provide more valid and accurate information about root resorption.

  6. Action of plant root exudates in bioremediations: a review

    Directory of Open Access Journals (Sweden)

    Peter Dundek

    2011-01-01

    Full Text Available This work presents a summary of literature dealing with the use of plant root exudates in bioremediations. Bioremediation using plants (phytoremediation or rhizoremediation and associate rhizosphere to decontaminate polluted soil is a method based on the catabolic potential of root-associated microorganisms, which are supported by the organic substrates released from roots. These substrates are called “root exudates”. Root exudates support metabolism of pollutants-decomposing microorganisms in the rhizosphere, and affect sorption / desorption of pollutants. Awareness of exudation rates is necessary for testing soil decontamination. Commonly, water-soluble root exudates of different plants are studied for their qualitative composition which should be related to total carbon of exuded water-soluble compounds. This paper presents the determined rate of plant root exudation and the amount of root exudates carbon used to form artificial rhizosphere.

  7. The Interaction between Auxin and Nitric Oxide Regulates Root Growth in Response to Iron Deficiency in Rice

    Directory of Open Access Journals (Sweden)

    Huwei Sun

    2017-12-01

    Full Text Available Fe deficiency (-Fe is a common abiotic stress that affects the root development of plants. Auxin and nitric oxide (NO are key regulator of root growth under -Fe. However, the interactions between auxin and NO regulate root growth in response to Fe deficiency are complex and unclear. In this study, the indole-3-acetic acid (IAA and NO levels in roots, and the responses of root growth in rice to different levels of Fe supply were investigated using wild type (WT, ospin1b and osnia2 mutants. -Fe promoted LR formation but inhibited seminal root elongation. IAA levels, [3H] IAA transport, and expression levels of PIN1a-c genes in roots were reduced under -Fe, suggesting that polar auxin transport from shoots to roots was decreased. Application of IAA to -Fe seedlings restored seminal root length, but not LR density, to levels similar to those under normal Fe (+Fe, and the seminal root length was shorter in two ospin1b mutants relative to WT under +Fe, but not under -Fe, confirming that auxin transport participates in -Fe-inhibited seminal root elongation. Moreover, -Fe-induced LR density and -Fe-inhibited seminal root elongation paralleled NO production in roots. Interestingly, similar NO accumulation and responses of LR density and root elongation were observed in osnia2 mutants compared to WT, and the higher expression of NOA gene under -Fe, suggesting that -Fe-induced NO was generated via the NO synthase-like pathway rather than the nitrate reductase pathway. However, IAA could restore the functions of NO in inhibiting seminal root elongation, but did not replace the role of NO-induced LR formation under -Fe. Overall, our findings suggested that NO functions downstream of auxin in regulating LR formation; NO-inhibited seminal root elongation by decreasing meristem activity in root tips under -Fe, with the involvement of auxin.

  8. Advancements in Root Growth Measurement Technologies and Observation Capabilities for Container-Grown Plants

    Directory of Open Access Journals (Sweden)

    Lesley A. Judd

    2015-07-01

    Full Text Available The study, characterization, observation, and quantification of plant root growth and root systems (Rhizometrics has been and remains an important area of research in all disciplines of plant science. In the horticultural industry, a large portion of the crops grown annually are grown in pot culture. Root growth is a critical component in overall plant performance during production in containers, and therefore it is important to understand the factors that influence and/or possible enhance it. Quantifying root growth has varied over the last several decades with each method of quantification changing in its reliability of measurement and variation among the results. Methods such as root drawings, pin boards, rhizotrons, and minirhizotrons initiated the aptitude to measure roots with field crops, and have been expanded to container-grown plants. However, many of the published research methods are monotonous and time-consuming. More recently, computer programs have increased in use as technology advances and measuring characteristics of root growth becomes easier. These programs are instrumental in analyzing various root growth characteristics, from root diameter and length of individual roots to branching angle and topological depth of the root architecture. This review delves into the expanding technologies involved with expertly measuring root growth of plants in containers, and the advantages and disadvantages that remain.

  9. Advancements in Root Growth Measurement Technologies and Observation Capabilities for Container-Grown Plants.

    Science.gov (United States)

    Judd, Lesley A; Jackson, Brian E; Fonteno, William C

    2015-07-03

    The study, characterization, observation, and quantification of plant root growth and root systems (Rhizometrics) has been and remains an important area of research in all disciplines of plant science. In the horticultural industry, a large portion of the crops grown annually are grown in pot culture. Root growth is a critical component in overall plant performance during production in containers, and therefore it is important to understand the factors that influence and/or possible enhance it. Quantifying root growth has varied over the last several decades with each method of quantification changing in its reliability of measurement and variation among the results. Methods such as root drawings, pin boards, rhizotrons, and minirhizotrons initiated the aptitude to measure roots with field crops, and have been expanded to container-grown plants. However, many of the published research methods are monotonous and time-consuming. More recently, computer programs have increased in use as technology advances and measuring characteristics of root growth becomes easier. These programs are instrumental in analyzing various root growth characteristics, from root diameter and length of individual roots to branching angle and topological depth of the root architecture. This review delves into the expanding technologies involved with expertly measuring root growth of plants in containers, and the advantages and disadvantages that remain.

  10. Morphological plasticity of root growth under mild water stress increases water use efficiency without reducing yield in maize

    Science.gov (United States)

    Cai, Qian; Zhang, Yulong; Sun, Zhanxiang; Zheng, Jiaming; Bai, Wei; Zhang, Yue; Liu, Yang; Feng, Liangshan; Feng, Chen; Zhang, Zhe; Yang, Ning; Evers, Jochem B.; Zhang, Lizhen

    2017-08-01

    A large yield gap exists in rain-fed maize (Zea mays L.) production in semi-arid regions, mainly caused by frequent droughts halfway through the crop-growing period due to uneven distribution of rainfall. It is questionable whether irrigation systems are economically required in such a region since the total amount of rainfall does generally meet crop requirements. This study aimed to quantitatively determine the effects of water stress from jointing to grain filling on root and shoot growth and the consequences for maize grain yield, above- and below-ground dry matter, water uptake (WU) and water use efficiency (WUE). Pot experiments were conducted in 2014 and 2015 with a mobile rain shelter to achieve conditions of no, mild or severe water stress. Maize yield was not affected by mild water stress over 2 years, while severe stress reduced yield by 56 %. Both water stress levels decreased root biomass slightly but shoot biomass substantially. Mild water stress decreased root length but increased root diameter, resulting in no effect on root surface area. Due to the morphological plasticity in root growth and the increase in root / shoot ratio, WU under water stress was decreased, and overall WUE for both above-ground dry matter and grain yield increased. Our results demonstrate that an irrigation system might be not economically and ecologically necessary because the frequently occurring mild water stress did not reduce crop yield much. The study helps us to understand crop responses to water stress during a critical water-sensitive period (middle of the crop-growing season) and to mitigate drought risk in dry-land agriculture.

  11. Assessment of three root canal preparation techniques on root canal geometry using micro-computed tomography: In vitro study

    Directory of Open Access Journals (Sweden)

    Shaikha M Al-Ali

    2012-01-01

    Full Text Available Aim: To assess the effects of three root canal preparation techniques on canal volume and surface area using three-dimensionally reconstructed root canals in extracted human maxillary molars. Materials and Methods: Thirty extracted Human Maxillary Molars having three separate roots and similar root shape were randomly selected from a pool of extracted teeth for this study and stored in normal saline solution until used. A computed tomography scanner (Philips Brilliance CT 64-slice was used to analyze root canals in extracted maxillary molars. Specimens were scanned before and after canals were prepared using stainless steel K-Files, Ni-Ti rotary ProTaper and rotary SafeSiders instruments. Differences in dentin volume removed, the surface area, the proportion of unchanged area and canal transportation were calculated using specially developed software. Results: Instrumentation of canals increased volume and surface area. Statistical analysis found a statistically significant difference among the 3 groups in total change in volume (P = 0.001 and total change in surface area (P = 0.13. Significant differences were found when testing both groups with group III (SafeSiders. Significant differences in change of volume were noted when grouping was made with respect to canal type (in MB and DB (P < 0.05. Conclusion: The current study used computed tomography, an innovative and non destructive technique, to illustrate changes in canal geometry. Overall, there were few statistically significant differences between the three instrumentation techniques used. SafeSiders stainless steel 40/0.02 instruments exhibit a greater cutting efficiency on dentin than K-Files and ProTaper. CT is a new and valuable tool to study root canal geometry and changes after preparation in great details. Further studies with 3D-techniques are required to fully understand the biomechanical aspects of root canal preparation.

  12. Root dynamics in an artificially constructed regenerating longleaf pine ecosystem are affected by atmospheric CO(2) enrichment.

    Science.gov (United States)

    Pritchard, S G.; Davis, M A.; Mitchell, R J.; Prior, S A.; Boykin, D L.; Rogers, H H.; Runion, G B.

    2001-08-01

    Differential responses to elevated atmospheric CO(2) concentration exhibited by different plant functional types may alter competition for above- and belowground resources in a higher CO(2) world. Because C allocation to roots is often favored over C allocation to shoots in plants grown with CO(2) enrichment, belowground function of forest ecosystems may change significantly. We established an outdoor facility to examine the effects of elevated CO(2) on root dynamics in artificially constructed communities of five early successional forest species: (1) a C(3) evergreen conifer (longleaf pine, Pinus palustris Mill.); (2) a C(4) monocotyledonous bunch grass (wiregrass, Aristida stricta Michx.); (3) a C(3) broadleaf tree (sand post oak, Quercus margaretta); (4) a C(3) perennial herbaceous legume (rattlebox, Crotalaria rotundifolia Walt. ex Gemel); and (5) an herbaceous C(3) dicotyledonous perennial (butterfly weed, Asclepias tuberosa L.). These species are common associates in early successional longleaf pine savannahs throughout the southeastern USA and represent species that differ in life-form, growth habit, physiology, and symbiotic relationships. A combination of minirhizotrons and soil coring was used to examine temporal and spatial rooting dynamics from October 1998 to October 1999. CO(2)-enriched plots exhibited 35% higher standing root crop length, 37% greater root length production per day, and 47% greater root length mortality per day. These variables, however, were enhanced by CO(2) enrichment only at the 10-30 cm depth. Relative root turnover (flux/standing crop) was unchanged by elevated CO(2). Sixteen months after planting, root biomass of pine was 62% higher in elevated compared to ambient CO(2) plots. Conversely, the combined biomass of rattlebox, wiregrass, and butterfly weed was 28% greater in ambient compared to high CO(2) plots. There was no difference in root biomass of oaks after 16 months of exposure to elevated CO(2). Using root and shoot

  13. Myelography for nerve root avulsion in birth palsy

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Tsutomu; Mitomo, Masanori; Hirabuki, Norio; Miura, Takashi; Kawai, Ryuji; Imakita, Satoshi; Harada, Koshi; Nakamura, Hironobu; Kozuka, Takahiro (Osaka Univ. (Japan). Faculty of Medicine)

    1990-04-01

    Myelography and CT myelography (CMT) were reviewed in 18 cases of birth palsy with clinically suspected avulsion injury. Root-somatosensory evoked potential (root-SEP) was also reviewed for myelographic evaluation of the nerve root avolusion in birth palsy. Root-SEP is not induced in case of avulsed nerve roots, but is induced in case of both normal and incompletely avulsed roots. Myelography demonstrated 58 abnormal nerve roots in 18 cases (19 limbs); 45 (78%) complete and 13 (22%) incomplete nerve root avulsions. Each of complete and incomplete avulsions was defined as total absence and partial presence of rootlets on myelography, respectively. Traumatic meningoceles were detected at 46 roots (79%) on myelography and/or CTM; 35 roots on myelography and 45 roots on CTM. CTM could not detect only a very small meningocele at one root. At 11 roots CTM was superior to myelography in delineating a meningocele because CTM is sensitive to a poorly enhanced meningocele. CTM, however, could not diagnose nerve root avulsions so accurately as myelography, since myelography detected 12 (7 completely and 5 incompletely) avulsed roots without meningocele, whereas CTM could not delineate the nerve roots clearly. Thus, myelography is indispensable to evaluate nerve root avulsions without meningocele. Root-SEP was examined in 9 patients who underwent branchial plexus exploration. SEP was negative at 22/25 roots with complete avulsion and was positive at 7/7 roots with myelographically incomplete avulsion, regardless of presence or absence of any traumatic meningocele. Myelography and root-SEP correlated well at 29 (92%) out of 32 roots in evaluating complete and incomplete avulsion injuries. Myelography and root-SEP were not considered in 3 roots. Though myelography demonstrated complete avulsions with traumatic meningocele, SEP was positive in these three roots, which were interpreted as partially avulsed roots. (J.P.N.).

  14. Myelography for nerve root avulsion in birth palsy

    International Nuclear Information System (INIS)

    Hashimoto, Tsutomu; Mitomo, Masanori; Hirabuki, Norio; Miura, Takashi; Kawai, Ryuji; Imakita, Satoshi; Harada, Koshi; Nakamura, Hironobu; Kozuka, Takahiro

    1990-01-01

    Myelography and CT myelography (CMT) were reviewed in 18 cases of birth palsy with clinically suspected avulsion injury. Root-somatosensory evoked potential (root-SEP) was also reviewed for myelographic evaluation of the nerve root avolusion in birth palsy. Root-SEP is not induced in case of avulsed nerve roots, but is induced in case of both normal and incompletely avulsed roots. Myelography demonstrated 58 abnormal nerve roots in 18 cases (19 limbs); 45 (78%) complete and 13 (22%) incomplete nerve root avulsions. Each of complete and incomplete avulsions was defined as total absence and partial presence of rootlets on myelography, respectively. Traumatic meningoceles were detected at 46 roots (79%) on myelography and/or CTM; 35 roots on myelography and 45 roots on CTM. CTM could not detect only a very small meningocele at one root. At 11 roots CTM was superior to myelography in delineating a meningocele because CTM is sensitive to a poorly enhanced meningocele. CTM, however, could not diagnose nerve root avulsions so accurately as myelography, since myelography detected 12 (7 completely and 5 incompletely) avulsed roots without meningocele, whereas CTM could not delineate the nerve roots clearly. Thus, myelography is indispensable to evaluate nerve root avulsions without meningocele. Root-SEP was examined in 9 patients who underwent branchial plexus exploration. SEP was negative at 22/25 roots with complete avulsion and was positive at 7/7 roots with myelographically incomplete avulsion, regardless of presence or absence of any traumatic meningocele. Myelography and root-SEP correlated well at 29 (92%) out of 32 roots in evaluating complete and incomplete avulsion injuries. Myelography and root-SEP were not considered in 3 roots. Though myelography demonstrated complete avulsions with traumatic meningocele, SEP was positive in these three roots, which were interpreted as partially avulsed roots. (J.P.N.)

  15. An unbiased stereological method for efficiently quantifying the innervation of the heart and other organs based on total length estimations

    DEFF Research Database (Denmark)

    Mühlfeld, Christian; Papadakis, Tamara; Krasteva, Gabriela

    2010-01-01

    Quantitative information about the innervation is essential to analyze the structure-function relationships of organs. So far, there has been no unbiased stereological tool for this purpose. This study presents a new unbiased and efficient method to quantify the total length of axons in a given...... reference volume, illustrated on the left ventricle of the mouse heart. The method is based on the following steps: 1) estimation of the reference volume; 2) randomization of location and orientation using appropriate sampling techniques; 3) counting of nerve fiber profiles hit by a defined test area within...

  16. On the total number of genes and their length distribution in complete microbial genomes

    DEFF Research Database (Denmark)

    Skovgaard, M; Jensen, L J; Brunak, S

    2001-01-01

    In sequenced microbial genomes, some of the annotated genes are actually not protein-coding genes, but rather open reading frames that occur by chance. Therefore, the number of annotated genes is higher than the actual number of genes for most of these microbes. Comparison of the length distribut......In sequenced microbial genomes, some of the annotated genes are actually not protein-coding genes, but rather open reading frames that occur by chance. Therefore, the number of annotated genes is higher than the actual number of genes for most of these microbes. Comparison of the length...... distribution of the annotated genes with the length distribution of those matching a known protein reveals that too many short genes are annotated in many genomes. Here we estimate the true number of protein-coding genes for sequenced genomes. Although it is often claimed that Escherichia coli has about 4300...... genes, we show that it probably has only approximately 3800 genes, and that a similar discrepancy exists for almost all published genomes....

  17. N,N-dimethyl hexadecylamine and related amines regulate root morphogenesis via jasmonic acid signaling in Arabidopsis thaliana.

    Science.gov (United States)

    Raya-González, Javier; Velázquez-Becerra, Crisanto; Barrera-Ortiz, Salvador; López-Bucio, José; Valencia-Cantero, Eduardo

    2017-05-01

    Plant growth-promoting rhizobacteria are natural inhabitants of roots, colonize diverse monocot and dicot species, and affect several functional traits such as root architecture, adaptation to adverse environments, and protect plants from pathogens. N,N-dimethyl-hexadecylamine (C16-DMA) is a rhizobacterial amino lipid that modulates the postembryonic development of several plants, likely as part of volatile blends. In this work, we evaluated the bioactivity of C16-DMA and other related N,N-dimethyl-amines with varied length and found that inhibition of primary root growth was related to the length of the acyl chain. C16-DMA inhibited primary root growth affecting cell division and elongation, while promoting lateral root formation and root hair growth and density in Arabidopsis thaliana (Arabidopsis) wild-type (WT) seedlings. Interestingly, C16-DMA induced the expression of the jasmonic acid (JA)-responsive gene marker pLOX2:uidA, while JA-related mutants jar1, coi1-1, and myc2 affected on JA biosynthesis and perception, respectively, are compromised in C16-DMA responses. Comparison of auxin-regulated gene expression, root architectural changes in WT, and auxin-related mutants aux1-7, tir1/afb2/afb3, and arf7-1/arf19-1 to C16-DMA shows that the C16-DMA effects occur independently of auxin signaling. Together, these results reveal a novel class of aminolipids modulating root organogenesis via crosstalk with the JA signaling pathway.

  18. Polyamines and adventitious root formation in Vitis vinifera L.

    Directory of Open Access Journals (Sweden)

    Laurence Geny

    2002-06-01

    Full Text Available The effects of polyamines were examined for growth and polyamine contents in cultings, callus and primary adventitious roots of Vitis vinifera L. Variations in free, conjugated and wall-bound polyamines in cuttings were observed during rhizogenesis. The main polyamines in cuttings were conjugated polyamines while in callus and primary adventitious roots they were free polyamines. Exogenous polyamine addition did not modify the total number of roots per cutting but increased the mean size and number of long roots. Moreover, exogenous polyamines increased polyamine levels in callus and roots, particurlarly wall-bound and conjugated polyamines. The involvement of these classes of polyamines in morphogenic processes is discussed.

  19. Community composition of root-associated fungi in a Quercus-dominated temperate forest: “codominance” of mycorrhizal and root-endophytic fungi

    Science.gov (United States)

    Toju, Hirokazu; Yamamoto, Satoshi; Sato, Hirotoshi; Tanabe, Akifumi S; Gilbert, Gregory S; Kadowaki, Kohmei

    2013-01-01

    In terrestrial ecosystems, plant roots are colonized by various clades of mycorrhizal and endophytic fungi. Focused on the root systems of an oak-dominated temperate forest in Japan, we used 454 pyrosequencing to explore how phylogenetically diverse fungi constitute an ecological community of multiple ecotypes. In total, 345 operational taxonomic units (OTUs) of fungi were found from 159 terminal-root samples from 12 plant species occurring in the forest. Due to the dominance of an oak species (Quercus serrata), diverse ectomycorrhizal clades such as Russula, Lactarius, Cortinarius, Tomentella, Amanita, Boletus, and Cenococcum were observed. Unexpectedly, the root-associated fungal community was dominated by root-endophytic ascomycetes in Helotiales, Chaetothyriales, and Rhytismatales. Overall, 55.3% of root samples were colonized by both the commonly observed ascomycetes and ectomycorrhizal fungi; 75.0% of the root samples of the dominant Q. serrata were so cocolonized. Overall, this study revealed that root-associated fungal communities of oak-dominated temperate forests were dominated not only by ectomycorrhizal fungi but also by diverse root endophytes and that potential ecological interactions between the two ecotypes may be important to understand the complex assembly processes of belowground fungal communities. PMID:23762515

  20. Mild salinity stimulates a stress-induced morphogenic response in Arabidopsis thaliana roots.

    Science.gov (United States)

    Zolla, Gaston; Heimer, Yair M; Barak, Simon

    2010-01-01

    Plant roots exhibit remarkable developmental plasticity in response to local soil conditions. It is shown here that mild salt stress stimulates a stress-induced morphogenic response (SIMR) in Arabidopsis thaliana roots characteristic of several other abiotic stresses: the proliferation of lateral roots (LRs) with a concomitant reduction in LR and primary root length. The LR proliferation component of the salt SIMR is dramatically enhanced by the transfer of seedlings from a low to a high NO3- medium, thereby compensating for the decreased LR length and maintaining overall LR surface area. Increased LR proliferation is specific to salt stress (osmotic stress alone has no stimulatory effect) and is due to the progression of more LR primordia from the pre-emergence to the emergence stage, in salt-stressed plants. In salt-stressed seedlings, greater numbers of LR primordia exhibit expression of a reporter gene driven by the auxin-sensitive DR5 promoter than in unstressed seedlings. Moreover, in the auxin transporter mutant aux1-7, the LR proliferation component of the salt SIMR is completely abrogated. The results suggest that salt stress promotes auxin accumulation in developing primordia thereby preventing their developmental arrest at the pre-emergence stage. Examination of ABA and ethylene mutants revealed that ABA synthesis and a factor involved in the ethylene signalling network also regulate the LR proliferation component of the salt SIMR.

  1. Effect of subsoil tillage depth on nutrient accumulation, root distribution, and grain yield in spring maize

    Directory of Open Access Journals (Sweden)

    Hongguang Cai

    2014-10-01

    Full Text Available A four-year field experiment was conducted to investigate the effect of subsoiling depth on root morphology, nitrogen (N, phosphorus (P, and potassium (K uptake, and grain yield of spring maize. The results indicated that subsoil tillage promoted root development, increased nutrient accumulation, and increased yield. Compared with conventional soil management (CK, root length, root surface area, and root dry weight at 0–80 cm soil depth under subsoil tillage to 30 cm (T1 and subsoil tillage to 50 cm (T2 were significantly increased, especially the proportions of roots in deeper soil. Root length, surface area, and dry weight differed significantly among three treatments in the order of T2 > T1 > CK at the 12-leaf and early filling stages. The range of variation of root diameter in different soil layers in T2 treatment was the smallest, suggesting that roots were more likely to grow downwards with deeper subsoil tillage in soil. The accumulation of N, P, and K in subsoil tillage treatment was significantly increased, but the proportions of kernel and straw were different. In a comparison of T1 with T2, the grain accumulated more N and P, while K accumulation in kernel and straw varied in different years. Grain yield and biomass were increased by 12.8% and 14.6% on average in subsoil tillage treatments compared to conventional soil treatment. Although no significant differences between different subsoil tillage depths were observed for nutrient accumulation and grain yield, lodging resistance of plants was significantly improved in subsoil tillage to 50 cm, a characteristic that favors a high and stable yield under extreme environments.

  2. Wheat shovelomics I: A field phenotyping approach for characterising the structure and function of root systems in tillering species

    OpenAIRE

    Bennett, Malcolm; York, Larry; Foulkes, M; Slack, Shaunagh

    2018-01-01

    Wheat represents a major crop, yet the current rate of yield improvement is insufficient to meet its projected global food demand. Breeding root systems more efficient for water and nitrogen capture represents a promising avenue for accelerating yield gains. Root crown phenotyping, or shovelomics, relies on excavation of the upper portions of root systems in the field and measuring root properties such as numbers, angles, densities and lengths. We report a new shovelomics method that images t...

  3. Auxin and Cytokinin Metabolism and Root Morphological Modifications in Arabidopsis thaliana Seedlings Infected with Cucumber mosaic virus (CMV or Exposed to Cadmium

    Directory of Open Access Journals (Sweden)

    Adriano Sofo

    2013-03-01

    Full Text Available Arabidopsis thaliana L. is a model plant but little information is available about morphological root changes as part of a phytohormonal common response against both biotic and abiotic stressors. For this purpose, two-week-old Arabidopsis seedlings were treated with 10 µM CdSO4 or infected with CMV. After 12 days the entire aerial parts and the root system were analyzed, and the presence of CMV or the accumulation of Cd were detected. Microscopic analysis revealed that both CMV and Cd influenced root morphology by a marked development in the length of root hairs and an intense root branching if compared to controls. Among the three treatments, Cd-treated seedlings showed a shorter root axis length and doubled their lateral root diameter, while the lateral roots of CMV-infected seedlings were the longest. The root growth patterns were accompanied by significant changes in the levels of indole-3-acetic acid, trans-zeatin riboside, dihydrozeatin riboside, as a probable consequence of the regulation of some genes involved in their biosynthesis/degradation. The opposite role on root development played by the phythormones studied is discussed in detail. The results obtained could provide insights into novel strategies for plant defense against pathogens and plant protection against pollutants.

  4. Auxin and cytokinin metabolism and root morphological modifications in Arabidopsis thaliana seedlings infected with Cucumber mosaic virus (CMV) or exposed to cadmium.

    Science.gov (United States)

    Vitti, Antonella; Nuzzaci, Maria; Scopa, Antonio; Tataranni, Giuseppe; Remans, Tony; Vangronsveld, Jaco; Sofo, Adriano

    2013-03-26

    Arabidopsis thaliana L. is a model plant but little information is available about morphological root changes as part of a phytohormonal common response against both biotic and abiotic stressors. For this purpose, two-week-old Arabidopsis seedlings were treated with 10 µM CdSO4 or infected with CMV. After 12 days the entire aerial parts and the root system were analyzed, and the presence of CMV or the accumulation of Cd were detected. Microscopic analysis revealed that both CMV and Cd influenced root morphology by a marked development in the length of root hairs and an intense root branching if compared to controls. Among the three treatments, Cd-treated seedlings showed a shorter root axis length and doubled their lateral root diameter, while the lateral roots of CMV-infected seedlings were the longest. The root growth patterns were accompanied by significant changes in the levels of indole-3-acetic acid, trans-zeatin riboside, dihydrozeatin riboside, as a probable consequence of the regulation of some genes involved in their biosynthesis/degradation. The opposite role on root development played by the phythormones studied is discussed in detail. The results obtained could provide insights into novel strategies for plant defense against pathogens and plant protection against pollutants.

  5. Root canal morphology of mandibular first premolar in a Gujarati population - An in vitro study

    Directory of Open Access Journals (Sweden)

    Atul Jain

    2011-01-01

    Full Text Available Background: Knowledge about root canal morphology and its frequent variations can exert considerable influence on the success of endodontic treatment. The aim of this study was to survey the root canal morphology of mandibular first premolar teeth in a Gujarati population by decalcification and clearing technique. Methods : One hundred thirty eight extracted mandibular first premolar teeth were collected from a Gujarati population. After decalcifying and clearing, the teeth were examined for tooth length, number of cusps and roots, number and shape of canal orifices and canal types. Results: The average length of mandibular first premolar teeth was 21.2 mm. All the teeth had 2 cusps. One hundred thirty four teeth (97.1% had one root, and just 4 teeth (2.89% had two roots. Mesial invagination of root was found in 21 teeth (15.21%. One canal orifice was found in 122 teeth (88.4% and two canal orifices in 16 teeth (11.59%. Shape of orifices was found to be round in 46 teeth (33.33%, oval in 72 teeth (52.17% and flattened ribbion in 20 teeth (14.49%. According to Vertucci′s classification, Type I canal system was found in 93 teeth (67.39%, Types II,III,IV,V,and VI in 11 teeth (7.97%, 5 teeth (3.62%, 4 teeth (2.89%, 24 teeth (17.39%, and 1 tooth (0.72% respectively. Conclusion: Mandibular first premolar teeth were mostly found to have one root and Type I canal system.

  6. Root-shoot relationships in four strains of field-grown Erianthus arundinaceus at seedling stage

    Directory of Open Access Journals (Sweden)

    Fumitaka Shiotsu

    2016-01-01

    Full Text Available The production of cellulosic bioethanol from non-edible plants is a potential countermeasure against global warming. Erianthus species provide cellulosic raw material for bioethanol because they have high biomass productivity and high tolerance to environmental stress, associated with their large, deep root systems. However, it is difficult to select Erianthus species for breeding by direct observation of their root systems because the roots are widely dispersed in the soil. Instead, we examined shoot morphological traits that could be closely related to root morphology to find effective reference indices for selection. The potential to evaluate root structure and function in Erianthus according to bleeding rate was also examined. An analysis of root–shoot relationships in seedlings indicated that root number and mean length were closely related to stem number and diameter, respectively. These results suggest that root–shoot relationships may provide useful criteria for selective breeding of root systems in Erianthus.

  7. Osmolarity and root canal antiseptics.

    Science.gov (United States)

    Rossi-Fedele, G; Guastalli, A R

    2014-04-01

    Antiseptics used in endodontics for disinfection purposes include root canal dressings and irrigants. Osmotic shock is known to cause the alteration of microbial cell viability and might have a role in the mechanism of action of root canal antiseptics. The aim of this review was to determine the role of osmolarity on the performance of antiseptics in root canal treatment. A literature search using the Medline electronic database was conducted up to 30 May 2013 using the following search terms and combinations: 'osmolarity AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm; osmolality AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm; osmotic AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm; osmosis AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm; sodium chloride AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm'. Publications were included if the effects of osmolarity on the clinical performance of antiseptics in root canal treatment were stated, if preparations with different osmolarities values were compared and if they were published in English. A hand search of articles published online, 'in press' and 'early view', and in the reference list of the included papers was carried out following the same criteria. A total of 3274 publications were identified using the database, and three were included in the review. The evidence available in endodontics suggests a possible role for hyperosmotic root canal medicaments as disinfectants, and that there is no influence of osmolarity on the tissue dissolution capacity of sodium hypochlorite. There are insufficient data to obtain a sound conclusion regarding the role of hypo-osmosis in root canal disinfection, or osmosis in any further desirable

  8. Phytoremediation in the tropics--influence of heavy crude oil on root morphological characteristics of graminoids.

    Science.gov (United States)

    Merkl, Nicole; Schultze-Kraft, Rainer; Infante, Carmen

    2005-11-01

    When studying species for phytoremediation of petroleum-contaminated soils, one of the main traits is the root zone where enhanced petroleum degradation takes place. Root morphological characteristics of three tropical graminoids were studied. Specific root length (SRL), surface area, volume and average root diameter (ARD) of plants grown in crude oil-contaminated and uncontaminated soil were compared. Brachiaria brizantha and Cyperus aggregatus showed coarser roots in polluted soil compared to the control as expressed in an increased ARD. B. brizantha had a significantly larger specific root surface area in contaminated soil. Additionally, a shift of SRL and surface area per diameter class towards higher diameters was found. Oil contamination also caused a significantly smaller SRL and surface area in the finest diameter class of C. aggregatus. The root structure of Eleusine indica was not significantly affected by crude oil. Higher specific root surface area was related to higher degradation of petroleum hydrocarbons found in previous studies.

  9. Root foraging increases performance of the clonal plant Potentilla reptans in heterogeneous nutrient environments.

    Science.gov (United States)

    Wang, Zhengwen; van Kleunen, Mark; During, Heinjo J; Werger, Marinus J A

    2013-01-01

    Plastic root-foraging responses have been widely recognized as an important strategy for plants to explore heterogeneously distributed resources. However, the benefits and costs of root foraging have received little attention. In a greenhouse experiment, we grew pairs of connected ramets of 22 genotypes of the stoloniferous plant Potentilla reptans in paired pots, between which the contrast in nutrient availability was set as null, medium and high, but with the total nutrient amount kept the same. We calculated root-foraging intensity of each individual ramet pair as the difference in root mass between paired ramets divided by the total root mass. For each genotype, we then calculated root-foraging ability as the slope of the regression of root-foraging intensity against patch contrast. For all genotypes, root-foraging intensity increased with patch contrast and the total biomass and number of offspring ramets were lowest at high patch contrast. Among genotypes, root-foraging intensity was positively related to production of offspring ramets and biomass in the high patch-contrast treatment, which indicates an evolutionary benefit of root foraging in heterogeneous environments. However, we found no significant evidence that the ability of plastic foraging imposes costs under homogeneous conditions (i.e. when foraging is not needed). Our results show that plants of P. reptans adjust their root-foraging intensity according to patch contrast. Moreover, the results show that the root foraging has an evolutionary advantage in heterogeneous environments, while costs of having the ability of plastic root foraging were absent or very small.

  10. Vegetative propagation by root and stem cuttings of Leptadenia ...

    African Journals Online (AJOL)

    The aim of this study was to investigate the possibilities of the propagation of Leptadenia hastata cuttings during the 3 seasons of the year in Sahel. The cuttings of 20 cm of length, collected from the basal, apical and root parts of the plants, were used. Study investigations consisted in observing the buds and leaves ...

  11. Changes in hormonal balance and meristematic activity in primary root tips on the slowly rotating clinostat and their effect on the development of the rapeseed root system.

    Science.gov (United States)

    Aarrouf, J; Schoevaert, D; Maldiney, R; Perbal, G

    1999-04-01

    The morphometry of the root system, the meristematic activity and the level of indole-3-acetic acid (IAA), abscisic acid (ABA) and zeatin in the primary root tips of rapeseed seedlings were analyzed as functions of time on a slowly rotating clinostat (1 rpm) or in the vertical controls (1 rpm). The fresh weight of the root system was 30% higher throughout the growth period (25 days) in clinorotated seedlings. Morphometric analysis showed that the increase in biomass on the clinostat was due to greater primary root growth, earlier initiation and greater elongation of the secondary roots, which could be observed even in 5-day-old seedlings. However, after 15 days, the growth of the primary root slowed on the clinostat, whereas secondary roots still grew faster in clinorotated plants than in the controls. At this time, the secondary roots began to be initiated closer to the root tip on the clinostat than in the control. Analysis of the meristematic activity and determination of the levels in IAA, ABA and zeatin in the primary root tips demonstrated that after 5 days on the clinostat, the increased length of the primary root could be the consequence of higher meristematic activity and coincided with an increase in both IAA and ABA concentrations. After 15 days on the clinostat, a marked increase in IAA, ABA and zeatin, which probably reached supraoptimal levels, seems to cause a progressive disturbance of the meristematic cells, during a decrease of primary root growth between 15 and 25 days. These modifications in the hormonal balance and the perturbation of the meristematic activity on the clinostat were followed by a loss of apical dominance, which was responsible for the early initiation of secondary roots, the greater elongation of the root system and the emergence of the lateral roots near the tip of the primary root.

  12. The Effect of Lead on the Glomalin Content of Hypha and Root Reactive with Monoclonal Antibody and Bradford in both in Vitro and Pot Culture Conditions

    Directory of Open Access Journals (Sweden)

    Elham Malekzadeh

    2017-02-01

    Full Text Available Introduction: Glomalin is known as a specific fungal glycoprotein belonging to the order Glomerales in phylum Glomeromycota and has been introduced as a heat shock protein. We hypothesised that increasing the level of Pb would lead to increase in glomalin production. Glomalin is usually determined by two methods, the Bradford protein dye-binding assay and the enzyme-linked immunosorbent assay (ELISA. Since many laboratories are not equipped to carry out the ELISA assay, many studies have measured glomalin-related soil protein using the Bradford colorimetric total protein assay. While, the ELISA method specifically measures glomalin by using monoclonal antibody MAb32B11. Materials and Methods: The pot experiment was conducted in the sterile free-glomalin sand with Trifolium repens L. mycorrhized by Rhizophagus irregularis fungus and treated with the Pb levels of 0, 150, 300 and 450 µM. Thus, in vitro experiment was performed in two-compartments plates containing of the transformed carrot roots (Daucus carota L. mycorrhized with the same fungus in root compartment and hyphal compartment treated with the Pb levels of 0, 0.01, 0.1 and 1 mM as Pb(NO32. For glomalin extraction, hyphal or root samples were autoclaved at 121 ⁰C with 50 mM sodium citrate buffer for 60 min in three cycles. Protein concentrations in the extracted samples were determined using a modified Bradford protein assay. Also, glomalin content in the samples were determined by indirect ELISA using monoclonal antibody MAb32B11. The percentages of the total root length were colonised by mycorrhizal fungi in pot culture and both hyphal and spore densities in the metal-containing hyphal compartment were determined. Results and Discussion: In the in vitro culture the percentage of total hyphae and spore frequency decreased, while Bradford reactive total hyphal protein (BRHP and Immunoreactive hyphal protein (IRHP in hyphal compartment increased as the concentrations of Pb increased

  13. QTL mapping of root traits in phosphorus-deficient soils reveals important genomic regions for improving NDVI and grain yield in barley.

    Science.gov (United States)

    Gong, Xue; McDonald, Glenn

    2017-09-01

    Major QTLs for root rhizosheath size are not correlated with grain yield or yield response to phosphorus. Important QTLs were found to improve phosphorus efficiency. Root traits are important for phosphorus (P) acquisition, but they are often difficult to characterize and their breeding values are seldom assessed under field conditions. This has shed doubts on using seedling-based criteria of root traits to select and breed for P efficiency. Eight root traits were assessed under controlled conditions in a barley doubled-haploid population in soils differing in P levels. The population was also phenotyped for grain yield, normalized difference vegetation index (NDVI), grain P uptake and P utilization efficiency at maturity (PutE GY ) under field conditions. Several quantitative traits loci (QTLs) from the root screening and the field trials were co-incident. QTLs for root rhizosheath size and root diameter explained the highest phenotypic variation in comparison to QTLs for other root traits. Shared QTLs were found between root diameter and grain yield, and total root length and PutE GY . A common major QTL for rhizosheath size and NDVI was mapped to the HvMATE gene marker on chromosome 4H. Collocations between major QTLs for NDVI and grain yield were detected on chromosomes 6H and 7H. When results from BIP and MET were combined, QTLs detected for grain yield were also those QTLs found for NDVI. QTLs qGY5H, qGY6H and qGY7Hb on 7H were robust QTLs in improving P efficiency. A selection of multiple loci may be needed to optimize the breeding outcomes due to the QTL x Environment interaction. We suggest that rhizosheath size alone is not a reliable trait to predict P efficiency or grain yield.

  14. [Species-associated differences in foliage-root coupling soil-reinforcement and anti-erosion].

    Science.gov (United States)

    Liu, Fu-quan; Liu, Jing; Nao, Min; Yao, Xi-jun; Zheng, Yong-gang; Li, You-fang; Su, Yu; Wang, Chen-jia

    2015-02-01

    This paper took four kinds of common soil and water conservation plants of the study area, Caragana microphylla, Salix psammophila, Artemisia sphaerocephala and Hippophae rhamnides at ages of 4 as the research object. Thirteen indicators, i.e., single shrub to reduce wind velocity ration, shelterbelt reducing wind velocity ration, community reducing wind velocity ration, taproot tensile strength, representative root constitutive properties, representative root elasticity modulus, lateral root branch tensile strength, accumulative surface area, root-soil interface sheer strength, interface friction coefficient, accumulative root length, root-soil composite cohesive, root-soil composite equivalent friction angle, reflecting the characteristics of windbreak and roots, were chose to evaluate the differences of foliage-root coupling soil-reinforcement and anti-erosion among four kinds of plants by analytic hierarchy process (AHP) under the condition of spring gale and summer rainstorm, respectively. The results showed the anti-erosion index of foliage-root coupling was in the sequence of S. psammophila (0.841) > C. microphylla (0.454) > A. sphaerocephala (-0.466) > H. rhamnides (-0.829) in spring gale, and C. microphylla (0.841) > S. psammophila (0. 474) > A. sphaerocephala (-0.470) > H. rhamnides (-0.844) in summer rainstorm. S. psammophila could be regarded as one of the most important windbreak and anti-erosion species, while C. microphylla could be the most valuable soil and water conservation plant for the study area.

  15. Ethylene-auxin interactions regulate lateral root initiation and emergence in Arabidopsis thaliana.

    Science.gov (United States)

    Ivanchenko, Maria G; Muday, Gloria K; Dubrovsky, Joseph G

    2008-07-01

    Plant root systems display considerable plasticity in response to endogenous and environmental signals. Auxin stimulates pericycle cells within elongating primary roots to enter de novo organogenesis, leading to the establishment of new lateral root meristems. Crosstalk between auxin and ethylene in root elongation has been demonstrated, but interactions between these hormones in root branching are not well characterized. We find that enhanced ethylene synthesis, resulting from the application of low concentrations of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), promotes the initiation of lateral root primordia. Treatment with higher doses of ACC strongly inhibits the ability of pericycle cells to initiate new lateral root primordia, but promotes the emergence of existing lateral root primordia: behaviour that is also seen in the eto1 mutation. These effects are correlated with decreased pericycle cell length and increased lateral root primordia cell width. When auxin is applied simultaneously with ACC, ACC is unable to prevent the auxin stimulation of lateral root formation in the root tissues formed prior to ACC exposure. However, in root tissues formed after transfer to ACC, in which elongation is reduced, auxin does not rescue the ethylene inhibition of primordia initiation, but instead increases it by several fold. Mutations that block auxin responses, slr1 and arf7 arf19, render initiation of lateral root primordia insensitive to the promoting effect of low ethylene levels, and mutations that inhibit ethylene-stimulated auxin biosynthesis, wei2 and wei7, reduce the inhibitory effect of higher ethylene levels, consistent with ethylene regulating root branching through interactions with auxin.

  16. Intraflagellar transport particle size scales inversely with flagellar length: revisiting the balance-point length control model.

    Science.gov (United States)

    Engel, Benjamin D; Ludington, William B; Marshall, Wallace F

    2009-10-05

    The assembly and maintenance of eukaryotic flagella are regulated by intraflagellar transport (IFT), the bidirectional traffic of IFT particles (recently renamed IFT trains) within the flagellum. We previously proposed the balance-point length control model, which predicted that the frequency of train transport should decrease as a function of flagellar length, thus modulating the length-dependent flagellar assembly rate. However, this model was challenged by the differential interference contrast microscopy observation that IFT frequency is length independent. Using total internal reflection fluorescence microscopy to quantify protein traffic during the regeneration of Chlamydomonas reinhardtii flagella, we determined that anterograde IFT trains in short flagella are composed of more kinesin-associated protein and IFT27 proteins than trains in long flagella. This length-dependent remodeling of train size is consistent with the kinetics of flagellar regeneration and supports a revised balance-point model of flagellar length control in which the size of anterograde IFT trains tunes the rate of flagellar assembly.

  17. Growth and Anatomical Parameters of Adventitious Roots Formed on Mung Bean Hypocotyls Are Correlated with Galactoglucomannan Oligosaccharides Structure

    Directory of Open Access Journals (Sweden)

    K. Kollárová

    2012-01-01

    Full Text Available The effect of galactoglucomannan oligosaccharides (GGMOs compared with chemically modified oligosaccharides, GGMOs-g (with reduced number of D-galactose side chains and GGMOs-r (with reduced reducing ends on mung bean (Vigna radiata (L. Wilczek adventitious roots formation, elongation, and anatomical structure have been studied. All types of oligosaccharides influenced adventitious root formation in the same way: stimulation in the absence of exogenous auxin and inhibition in the presence of exogenous auxin. Both reactions are probably related with the presence/content of endogenous auxin in plant cuttings. However, the adventitious root length was inhibited by GGMOs both in the absence as well as in the presence of auxin (IBA or NAA, while GGMOs-g inhibition was significantly weaker compared with GGMOs. GGMOs-r were without significant difference on both processes, compared with GGMOs. GGMOs affected not only the adventitious root length but also their anatomy in dependence on the combination with certain type of auxin. The oligosaccharides influenced cortical cells division, which was reflected in the cortex area and in the root diameter. All processes followed were dependent on oligosaccharides chemical structure. The results suggest also that GGM-derived oligosaccharides may play an important role in adventitious roots elongation but not in their formation.

  18. Root bacterial endophytes alter plant phenotype, but not physiology

    DEFF Research Database (Denmark)

    Henning, Jeremiah A.; Weston, David J.; Pelletier, Dale A.

    2016-01-01

    (root:shoot, biomass production, root and leaf growth rates) and physiological traits (chlorophyll content, net photosynthesis, net photosynthesis at saturating light-Asat, and saturating CO2-Amax). Overall, we found that bacterial root endophyte infection increased root growth rate up to 184% and leaf...... growth rate up to 137% relative to non-inoculated control plants, evidence that plants respond to bacteria by modifying morphology. However, endophyte inoculation had no influence on total plant biomass and photosynthetic traits (net photosynthesis, chlorophyll content). In sum, bacterial inoculation did......Plant traits, such as root and leaf area, influence how plants interact with their environment and the diverse microbiota living within plants can influence plant morphology and physiology. Here, we explored how three bacterial strains isolated from the Populus root microbiome, influenced plant...

  19. Analysis of expressed sequence tags generated from full-length enriched cDNA libraries of melon

    Directory of Open Access Journals (Sweden)

    Bendahmane Abdelhafid

    2011-05-01

    Full Text Available Abstract Background Melon (Cucumis melo, an economically important vegetable crop, belongs to the Cucurbitaceae family which includes several other important crops such as watermelon, cucumber, and pumpkin. It has served as a model system for sex determination and vascular biology studies. However, genomic resources currently available for melon are limited. Result We constructed eleven full-length enriched and four standard cDNA libraries from fruits, flowers, leaves, roots, cotyledons, and calluses of four different melon genotypes, and generated 71,577 and 22,179 ESTs from full-length enriched and standard cDNA libraries, respectively. These ESTs, together with ~35,000 ESTs available in public domains, were assembled into 24,444 unigenes, which were extensively annotated by comparing their sequences to different protein and functional domain databases, assigning them Gene Ontology (GO terms, and mapping them onto metabolic pathways. Comparative analysis of melon unigenes and other plant genomes revealed that 75% to 85% of melon unigenes had homologs in other dicot plants, while approximately 70% had homologs in monocot plants. The analysis also identified 6,972 gene families that were conserved across dicot and monocot plants, and 181, 1,192, and 220 gene families specific to fleshy fruit-bearing plants, the Cucurbitaceae family, and melon, respectively. Digital expression analysis identified a total of 175 tissue-specific genes, which provides a valuable gene sequence resource for future genomics and functional studies. Furthermore, we identified 4,068 simple sequence repeats (SSRs and 3,073 single nucleotide polymorphisms (SNPs in the melon EST collection. Finally, we obtained a total of 1,382 melon full-length transcripts through the analysis of full-length enriched cDNA clones that were sequenced from both ends. Analysis of these full-length transcripts indicated that sizes of melon 5' and 3' UTRs were similar to those of tomato, but

  20. Relationships of body lengths with mouth opening and prey length of nemipterid fishes (Regan, 1913 in the Gulf of Thailand

    Directory of Open Access Journals (Sweden)

    Mithun Paul

    2017-12-01

    Full Text Available This study aims to investigate the relationship among total length (TL of fish with mouth opening namely horizontal opening (MH, vertical opening (VH, mouth area (MA and fork length (FL of seven sympatric nemipterid fish species and to know the relationship between total length and consumed prey length of five sympatric species sampled from the Gulf of Thailand in 2015. A total 883 fish were investigated collected from both cruise surveys and fishing port survey. TL was linearly and log-linearly related with both MV and MH for three and four species, respectively. MA’s were always the log linear relation of TL and shapes were nearly oval for all species. FL in all TL-FL relationships were proportional to the TL’s in all species (r2 = 0.94, P  .5 and in invertebrate prey items for N. tambuloides (P > .5. So, this study clearly confirms that nemipterid fishes of different sizes feed on all different specific prey items according to its own body size and feed according to size class for prey items available nearby.

  1. Source and magnitude of ammonium generation in maize roots

    International Nuclear Information System (INIS)

    Feng, J.; Vol, R.J.; Jackson, W.A.

    1998-01-01

    Studies with 15 N indicate that appreciable generation of NH 4 + from endogenous sources accompanies the uptake and assimilation of exogenous NH 4 + by roots. To identify the source of NH 4 + generation, maize (Zea mays L.) seedlings were grown on 14 NH 4 + and then exposed for 3 d to highly labeled 15 NH 4 + . More of the entering 15 NH 4 + was incorporated into the protein-N fraction of roots in darkness (approximately 25%) than in the light (approximately 14%). Although the 14 NH 4 + content of roots declined rapidly to less than 1 micromole per plant, efflux of 14 NH 4 + continued throughout the 3-d period at an average daily rate of 14 micromole per plant. As a consequence, cumulative 14 NH 4 + efflux during the 3-d period accounted for 25% of the total 14 N initially present in the root. Although soluble organic 14 N in roots declined during the 3-d period, insoluble 14 N remained relatively constant. In shoots both soluble organic 14 N and 14 NH 4 + declined, but a comparable increase in insoluble 14 N was noted. Thus, total 14 N in shoots remained constant, reflecting little or no net redistribution of 14 N between shoots and roots. Collectively, these observations reveal that catabolism of soluble organic N, not protein N, is the primary source of endogenous NH 4 + generation in maize roots. (author)

  2. The effect of limited availability of N or water on C allocation to fine roots and annual fine root turnover in Alnus incana and Salix viminalis.

    Science.gov (United States)

    Rytter, Rose-Marie

    2013-09-01

    The effect of limited nitrogen (N) or water availability on fine root growth and turnover was examined in two deciduous species, Alnus incana L. and Salix viminalis L., grown under three different regimes: (i) supply of N and water in amounts which would not hamper growth, (ii) limited N supply and (iii) limited water supply. Plants were grown outdoors during three seasons in covered and buried lysimeters placed in a stand structure and filled with quartz sand. Computer-controlled irrigation and fertilization were supplied through drip tubes. Production and turnover of fine roots were estimated by combining minirhizotron observations and core sampling, or by sequential core sampling. Annual turnover rates of fine roots water availability. Fine root production (treatments in Salix; i.e., absolute length and biomass production increased in the order: water limited treatment effects were detected for fine roots 1-2 mm. Proportionally more C was allocated to fine roots (≤2 mm) in N or water-limited Salix; 2.7 and 2.3 times the allocation to fine roots in the unlimited regime, respectively. Estimated input to soil organic carbon increased by ca. 20% at N limitation in Salix. However, future studies on fine root decomposition under various environmental conditions are required. Fine root growth responses to N or water limitation were less pronounced in Alnus, thus indicating species differences caused by N-fixing capacity and slower initial growth in Alnus, or higher fine root plasticity in Salix. A similar seasonal growth pattern across species and treatments suggested the influence of outer stimuli, such as temperature and light.

  3. The effect of photobiomodulation on root resorption during orthodontic treatment.

    Science.gov (United States)

    Nimeri, Ghada; Kau, Chung H; Corona, Rachel; Shelly, Jeffery

    2014-01-01

    Photobiomodulation is used to accelerate tooth movement during orthodontic treatments. The changes in root morphology in a group of orthodontic patients who received photobiomodulation were evaluated using the cone beam computed tomography technique. The device used is called OrthoPulse, which produces low levels of light with a near infrared wavelength of 850 nm and an intensity of 60 mW/cm(2) continuous wave. Twenty orthodontic patients were recruited for these experiments, all with class 1 malocclusion and with Little's Irregularity Index (>2 mm) in either of the arches. Root resorption was detected by measuring changes in tooth length using cone beam computed tomography. These changes were measured before the orthodontic treatment and use of low-level laser therapy and after finishing the alignment level. Little's Irregularity Index for all the patients was calculated in both the maxilla and mandible and patients were divided into three groups for further analysis, which were then compared to the root resorption measurements. Our results showed that photobiomodulation did not cause root resorption greater than the normal range that is commonly detected in orthodontic treatments. Furthermore, no correlation between Little's Irregularity Index and root resorption was detected.

  4. Synergistic and individual effect of glomus etunicatum root colonization and acetyl salicylic acid on root activity and architecture of tomato plants under moderate nacl stress

    International Nuclear Information System (INIS)

    Ghanzanfar, B.; Cheng, Z.; Ahmad, I.; Khan, A. R.; Hanqiang, L.; Haiyan, D.; Fang, C.

    2015-01-01

    A pot based experiment in plastic tunnel was conducted to investigate the changes in root morphology and root activity of the tomato plants grown under moderate NaCl stress (100 mM), pretreated with arbuscular mycorrhizal fungus AMF (Glomus etunicatum) root colonization and acetyl salicylic acid (ASA) as salinity ameliorative agents. The results revealed that both AMF and ASA treatments significantly enhanced the fresh root weight and root morphological parameters; net length, surface area, volume, mean diameter, nodal count and number of tips to different extents as compared to those of sole salinity treatment at 90 days after transplantation. Both treatments; AMF alone and in combination with ASA significantly enhanced the root activity level in terms of triphenyl tetrazolium chloride (TTC) reduction (2.37 and 2.40 mg g /sup -1/ h /sup -1/ respectively) as compared to the sole salinity treatment (0.40 mg g /sup -1/ h /sup -1/ ) as well as the salt free control (1.69 mg g /sup -1/ h /sup -1/) On the other hand, ASA treatment alone also uplifted root activity (1.53 mg g /sup -1/ h /sup -1/ ) which was significantly higher than that of sole salt treatment. It was inferred that under moderate saline conditions (100 mM NaCl), AMF (Glomus etunicatum) and ASA (individually or in combination) confer protective effect on plant growth by enhanced root activity and improved root architecture. Therefore, synergistic use of AMF (G. etunicatum) and ASA can be eco-friendly and economically feasible option for tomato production in marginally salt affected lands and suggests further investigations. (author)

  5. Phytoremediation in the tropics - influence of heavy crude oil on root morphological characteristics of graminoids

    International Nuclear Information System (INIS)

    Merkl, Nicole; Schultze-Kraft, Rainer; Infante, Carmen

    2005-01-01

    When studying species for phytoremediation of petroleum-contaminated soils, one of the main traits is the root zone where enhanced petroleum degradation takes place. Root morphological characteristics of three tropical graminoids were studied. Specific root length (SRL), surface area, volume and average root diameter (ARD) of plants grown in crude oil-contaminated and uncontaminated soil were compared. Brachiaria brizantha and Cyperus aggregatus showed coarser roots in polluted soil compared to the control as expressed in an increased ARD. B. brizantha had a significantly larger specific root surface area in contaminated soil. Additionally, a shift of SRL and surface area per diameter class towards higher diameters was found. Oil contamination also caused a significantly smaller SRL and surface area in the finest diameter class of C. aggregatus. The root structure of Eleusine indica was not significantly affected by crude oil. Higher specific root surface area was related to higher degradation of petroleum hydrocarbons found in previous studies. - Describing the effect of crude oil on root morphology of tropical graminoids the work assists in the selection of plant species for phytoremediation of oil-contaminated soils

  6. Phytoremediation in the tropics - influence of heavy crude oil on root morphological characteristics of graminoids

    Energy Technology Data Exchange (ETDEWEB)

    Merkl, Nicole [Institute of Plant Production and Agroecology in the Tropics and Subtropics, Department of Biodiversity and Land Rehabilitation, University of Hohenheim, D-70593 Stuttgart (Germany) and PDVSA - Intevep, Centro de Investigacion y Apoyo Tecnologico de Petroleos de Venezuela S.A., Departamento de Ecologia y Ambiente, P.O. Box 76343, Caracas 1070-A (Venezuela)]. E-mail: nmerkl@uni-hohenheim.de; Schultze-Kraft, Rainer [Institute of Plant Production and Agroecology in the Tropics and Subtropics, Department of Biodiversity and Land Rehabilitation, University of Hohenheim, D-70593 Stuttgart (Germany)]. E-mail: rsk@uni-hohenheim.de; Infante, Carmen [PDVSA - Intevep, Centro de Investigacion y Apoyo Tecnologico de Petroleos de Venezuela S.A., Departamento de Ecologia y Ambiente, P.O. Box 76343, Caracas 1070-A (Venezuela) and Universidad Simon Bolivar (USB), FUNINDES, Unidad de Gestion Ambiental, Caracas (Venezuela)]. E-mail: luchoben@cantv.net

    2005-11-15

    When studying species for phytoremediation of petroleum-contaminated soils, one of the main traits is the root zone where enhanced petroleum degradation takes place. Root morphological characteristics of three tropical graminoids were studied. Specific root length (SRL), surface area, volume and average root diameter (ARD) of plants grown in crude oil-contaminated and uncontaminated soil were compared. Brachiaria brizantha and Cyperus aggregatus showed coarser roots in polluted soil compared to the control as expressed in an increased ARD. B. brizantha had a significantly larger specific root surface area in contaminated soil. Additionally, a shift of SRL and surface area per diameter class towards higher diameters was found. Oil contamination also caused a significantly smaller SRL and surface area in the finest diameter class of C. aggregatus. The root structure of Eleusine indica was not significantly affected by crude oil. Higher specific root surface area was related to higher degradation of petroleum hydrocarbons found in previous studies. - Describing the effect of crude oil on root morphology of tropical graminoids the work assists in the selection of plant species for phytoremediation of oil-contaminated soils.

  7. Evaluation of Root Canal Cleaning and Shaping Efficacy of Three Engine-driven Instruments: SafeSider, ProTaper Universal and Lightspeed LSX.

    Science.gov (United States)

    Wigler, Ronald; Koren, Tal; Tsesis, Igor

    2015-11-01

    To compare the cleaning effectiveness and shaping ability of SafeSider, ProTaper Universal and Lightspeed rotary instruments during the preparation of curved root canals in extracted human teeth. A total of 63 roots with curved root canals were divided into three groups. Canals were prepared using SafeSider, ProTaper Universal or Lightspeed LSX. Using pre- and post-instrumentation radiographs, straightening of the canal curvatures and loss of working length were determined with a computer image analysis program. The amounts of debris at the apical 5 mm were quantified on the basis of a numerical evaluation scale. The data were analyzed statistically using the two-way analysis of variance (ANOVA). There was significantly more transportation among the Lightspeed LSX group compared to the SafeSider and ProTaper Universal groups only at the 4 mm level (p engine-driven instruments with regards to debris removal. SafeSider, ProTaper Universal and Lightspeed LSX rotary instruments maintained the original canal curvature well at the apical 3 mm and were safe to use. No difference was found in cleaning efficacy and none rendered the apical part of the canal free of debris. SafeSider, ProTaper Universal and Lightspeed LSX rotary instruments are safe to use in curved root canals.

  8. Effects of glucose and ethylene on root hair initiation and elongation in lettuce (Lactuca sativa L.) seedlings.

    Science.gov (United States)

    Harigaya, Wakana; Takahashi, Hidenori

    2018-05-01

    Root hair formation occurs in lettuce seedlings after transfer to an acidic medium (pH 4.0). This process requires cortical microtubule (CMT) randomization in root epidermal cells and the plant hormone ethylene. We investigated the interaction between ethylene and glucose, a new signaling molecule in plants, in lettuce root development, with an emphasis on root hair formation. Dark-grown seedlings were used to exclude the effect of photosynthetically produced glucose. In the dark, neither root hair formation nor the CMT randomization preceding it occurred, even after transfer to the acidic medium (pH 4.0). Adding 1-aminocyclopropane-1-carboxylic-acid (ACC) to the medium rescued the induction, while adding glucose did not. Although CMT randomization occurred when glucose was applied together with ACC, it was somewhat suppressed compared to that in ACC-treated seedlings. This was not due to a decrease in the speed of randomization, but due to lowering of the maximum degree of randomization. Despite the negative effect of glucose on ACC-induced CMT randomization, the density and length of ACC-induced root hairs increased when glucose was also added. The hair-cell length of the ACC-treated seedlings was comparable to that in the combined-treatment seedlings, indicating that the increase in hair density caused by glucose results from an increase in the root hair number. Furthermore, quantitative RT-PCR revealed that glucose suppressed ethylene signaling. These results suggest that glucose has a negative and positive effect on the earlier and later stages of root hair formation, respectively, and that the promotion of the initiation and elongation of root hairs by glucose may be mediated in an ethylene-independent manner.

  9. Morphological plasticity of root growth under mild water stress increases water use efficiency without reducing yield in maize

    Directory of Open Access Journals (Sweden)

    Q. Cai

    2017-08-01

    Full Text Available A large yield gap exists in rain-fed maize (Zea mays L. production in semi-arid regions, mainly caused by frequent droughts halfway through the crop-growing period due to uneven distribution of rainfall. It is questionable whether irrigation systems are economically required in such a region since the total amount of rainfall does generally meet crop requirements. This study aimed to quantitatively determine the effects of water stress from jointing to grain filling on root and shoot growth and the consequences for maize grain yield, above- and below-ground dry matter, water uptake (WU and water use efficiency (WUE. Pot experiments were conducted in 2014 and 2015 with a mobile rain shelter to achieve conditions of no, mild or severe water stress. Maize yield was not affected by mild water stress over 2 years, while severe stress reduced yield by 56 %. Both water stress levels decreased root biomass slightly but shoot biomass substantially. Mild water stress decreased root length but increased root diameter, resulting in no effect on root surface area. Due to the morphological plasticity in root growth and the increase in root ∕ shoot ratio, WU under water stress was decreased, and overall WUE for both above-ground dry matter and grain yield increased. Our results demonstrate that an irrigation system might be not economically and ecologically necessary because the frequently occurring mild water stress did not reduce crop yield much. The study helps us to understand crop responses to water stress during a critical water-sensitive period (middle of the crop-growing season and to mitigate drought risk in dry-land agriculture.

  10. Genetic Transformation and Hairy Root Induction Enhance the Antioxidant Potential of Lactuca serriola L.

    Directory of Open Access Journals (Sweden)

    Mohamed A. El-Esawi

    2017-01-01

    Full Text Available Lactuca serriola L. is a herbaceous species, used for human nutrition and medicinal purposes. The high antioxidant capacity of L. serriola indicates the possibility of enhancing its edible and health potential by increasing the flavonoid and phenolic contents. The present study aimed at enhancing the production of phenolics and flavonoids by hairy root cultures in Lactuca serriola transformed with Agrobacterium rhizogenes strain AR15834 harbouring the rolB gene. The genetic transformation of rolB in transformed roots was validated, and rolB expression level was evaluated using real-time qPCR analysis. Expression levels of flavonoid biosynthesis genes (CHI, PAL, FLS, and CHS were assessed in the hairy and nontransformed roots. Results showed higher expression levels in the transgenic roots than in the nontransformed ones (p<0.01. Transgenic hairy roots exhibited a 54.8–96.7% increase in the total phenolic content, 38.1–76.2% increase in the total flavonoid content, and 56.7–96.7% increase in the total reducing power when compared with the nontransgenic roots (p<0.01. DPPH results also revealed that the transgenic hairy roots exhibited a 31.6–50% increase in antioxidant potential, when compared to normal roots. This study addressed the enhancement of secondary metabolite biosynthesis by hairy root induction in L. serriola.

  11. Cotton growth potassium deficiency stress is influenced by photosynthetic apparatus and root system

    International Nuclear Information System (INIS)

    Hussain, Z.U.; Arshad, M.

    2010-01-01

    Due to rapid depletion of soil potassium (K) and increasing cost of K fertilizers in Pakistan, the K-use efficient crop genotypes become very important for agricultural sustain ability. However, limited research has been done on this important issue particularly in cotton, an important fibre crop. We studied the growth and biomass production of three cotton genotypes (CIM-506, NIAB- 78 and NIBGE-2) different in K-use efficiency in a K-deficient solution culture. Genotypes differed significantly for biomass production, absolute growth rates (shoot, root, leaf, total), leaf area, mean leaf area and relative growth rate of leaf under K deficiency stress, besides specific leaf area. The relative growth rate (shoot, root, total) did not differ significantly, except for leaf. For all these characters, NIBGE-2 was the best performer followed by NIAB-78 and CIM-506. Shoot dry weight was significantly related with (in decreasing order of significance): mean leaf area, leaf dry weight, leaf area, root dry weight, absolute growth rate of shoot, absolute growth rate of root, absolute growth rate total, absolute growth rate root, relative growth rate leaf, relative growth rate total and relative growth rate shoot. Hence, the enhanced biomass accumulation of cotton genotypes under K deficiency stress is related to their efficient photosynthetic apparatus and root system, appeared to be the most important morphological markers while breeding for K-use efficient cotton genotypes.(author)

  12. The effect of ovalbumin on orthodontic induced root resorption.

    Science.gov (United States)

    Aghili, Hosseinagha; Ardekani, Mohammad Danesh; Meybodi, Seyed Amir Reza Fatahi; Toodehzaeim, Mohammad Hossein; Modaresi, Jalil; Mansouri, Reza; Momeni, Ehsan

    2013-09-01

    This randomized trial was undertaken to investigate the effect of experimentally induced allergy on orthodontic induced root resorption. A total of 30 Wistar rats were divided randomly into test and control groups. Starting from the first 3 days, the rats in the test group were injected intra-peritoneally by 2 mg ovalbumin as allergen and 0.5 mg Alume as adjuvant. Afterward only allergen was injected once a week. The control group was injected by normal saline. After 21 days, Wistar immunoglobulin E was measured and peripheral matured eosinophil was counted. A total of 50 g nickel-titanium closed coil spring was ligated between right incisor and first molar. All animals were sacrificed after 14 days. The mesial root of the right and left first molar was dissected in a horizontal plane. The specimens were divided into four groups considering whether force and/or ovalbumin was applied or not. Root resorption was measured and compared among these groups. Repeated measures analysis of variance (ANOVA), and Bonferoni tests were used to analyze the data. The level of significance was determined at 0.05. In general, the differences were insignificant (P root resorption than the group in which neither force nor ovalbumin was applied (P > 0.001). Allergy may increase the susceptibility to root resorption. Application of light force, periodical monitoring of root resorption and control of allergy are advisable.

  13. Root rots

    Science.gov (United States)

    Kathryn Robbins; Philip M. Wargo

    1989-01-01

    Root rots of central hardwoods are diseases caused by fungi that infect and decay woody roots and sometimes also invade the butt portion of the tree. By killing and decaying roots, root rotting fungi reduce growth, decrease tree vigor, and cause windthrow and death. The most common root diseases of central hardwoods are Armillaria root rot, lnonotus root rot, and...

  14. Rhizoslides: paper-based growth system for non-destructive, high throughput phenotyping of root development by means of image analysis.

    Science.gov (United States)

    Le Marié, Chantal; Kirchgessner, Norbert; Marschall, Daniela; Walter, Achim; Hund, Andreas

    2014-01-01

    A quantitative characterization of root system architecture is currently being attempted for various reasons. Non-destructive, rapid analyses of root system architecture are difficult to perform due to the hidden nature of the root. Hence, improved methods to measure root architecture are necessary to support knowledge-based plant breeding and to analyse root growth responses to environmental changes. Here, we report on the development of a novel method to reveal growth and architecture of maize root systems. The method is based on the cultivation of different root types within several layers of two-dimensional, large (50 × 60 cm) plates (rhizoslides). A central plexiglass screen stabilizes the system and is covered on both sides with germination paper providing water and nutrients for the developing root, followed by a transparent cover foil to prevent the roots from falling dry and to stabilize the system. The embryonic roots grow hidden between a Plexiglas surface and paper, whereas crown roots grow visible between paper and the transparent cover. Long cultivation with good image quality up to 20 days (four fully developed leaves) was enhanced by suppressing fungi with a fungicide. Based on hyperspectral microscopy imaging, the quality of different germination papers was tested and three provided sufficient contrast to distinguish between roots and background (segmentation). Illumination, image acquisition and segmentation were optimised to facilitate efficient root image analysis. Several software packages were evaluated with regard to their precision and the time investment needed to measure root system architecture. The software 'Smart Root' allowed precise evaluation of root development but needed substantial user interference. 'GiaRoots' provided the best segmentation method for batch processing in combination with a good analysis of global root characteristics but overestimated root length due to thinning artefacts. 'WhinRhizo' offered the most rapid

  15. Mapping of a Novel Race Specific Resistance Gene to Phytophthora Root Rot of Pepper (Capsicum annuum) Using Bulked Segregant Analysis Combined with Specific Length Amplified Fragment Sequencing Strategy.

    Science.gov (United States)

    Xu, Xiaomei; Chao, Juan; Cheng, Xueli; Wang, Rui; Sun, Baojuan; Wang, Hengming; Luo, Shaobo; Xu, Xiaowan; Wu, Tingquan; Li, Ying

    2016-01-01

    Phytophthora root rot caused by Phytophthora capsici (P. capsici) is a serious limitation to pepper production in Southern China, with high temperature and humidity. Mapping PRR resistance genes can provide linked DNA markers for breeding PRR resistant varieties by molecular marker-assisted selection (MAS). Two BC1 populations and an F2 population derived from a cross between P. capsici-resistant accession, Criollo de Morelos 334 (CM334) and P. capsici-susceptible accession, New Mexico Capsicum Accession 10399 (NMCA10399) were used to investigate the genetic characteristics of PRR resistance. PRR resistance to isolate Byl4 (race 3) was controlled by a single dominant gene, PhR10, that was mapped to an interval of 16.39Mb at the end of the long arm of chromosome 10. Integration of bulked segregant analysis (BSA) and Specific Length Amplified Fragment sequencing (SLAF-seq) provided an efficient genetic mapping strategy. Ten polymorphic Simple Sequence Repeat (SSR) markers were found within this region and used to screen the genotypes of 636 BC1 plants, delimiting PhR10 to a 2.57 Mb interval between markers P52-11-21 (1.5 cM away) and P52-11-41 (1.1 cM). A total of 163 genes were annotated within this region and 31 were predicted to be associated with disease resistance. PhR10 is a novel race specific gene for PRR, and this paper describes linked SSR markers suitable for marker-assisted selection of PRR resistant varieties, also laying a foundation for cloning the resistance gene.

  16. Mapping of a Novel Race Specific Resistance Gene to Phytophthora Root Rot of Pepper (Capsicum annuum Using Bulked Segregant Analysis Combined with Specific Length Amplified Fragment Sequencing Strategy.

    Directory of Open Access Journals (Sweden)

    Xiaomei Xu

    Full Text Available Phytophthora root rot caused by Phytophthora capsici (P. capsici is a serious limitation to pepper production in Southern China, with high temperature and humidity. Mapping PRR resistance genes can provide linked DNA markers for breeding PRR resistant varieties by molecular marker-assisted selection (MAS. Two BC1 populations and an F2 population derived from a cross between P. capsici-resistant accession, Criollo de Morelos 334 (CM334 and P. capsici-susceptible accession, New Mexico Capsicum Accession 10399 (NMCA10399 were used to investigate the genetic characteristics of PRR resistance. PRR resistance to isolate Byl4 (race 3 was controlled by a single dominant gene, PhR10, that was mapped to an interval of 16.39Mb at the end of the long arm of chromosome 10. Integration of bulked segregant analysis (BSA and Specific Length Amplified Fragment sequencing (SLAF-seq provided an efficient genetic mapping strategy. Ten polymorphic Simple Sequence Repeat (SSR markers were found within this region and used to screen the genotypes of 636 BC1 plants, delimiting PhR10 to a 2.57 Mb interval between markers P52-11-21 (1.5 cM away and P52-11-41 (1.1 cM. A total of 163 genes were annotated within this region and 31 were predicted to be associated with disease resistance. PhR10 is a novel race specific gene for PRR, and this paper describes linked SSR markers suitable for marker-assisted selection of PRR resistant varieties, also laying a foundation for cloning the resistance gene.

  17. Cadmium and copper change root growth and morphology of Pinus pinea and Pinus pinaster seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Arduini, I.; Onnis, A. (Dipart. di Agronomia e Gestione dell' Agro-Ecosistema, Univ. degli Studi Pisa, Pisa (Italy)); Boldbold, D.L. (Forstbotanishces Institut, Univ. Goettingen, Goettingen (Germany))

    1994-01-01

    Heavy metal loads in forest soils have been increasing over time due to atmospheric inputs. Accumulation in the upper soil layers could affect establishment of seedlings and forest regeneration. Mediterranean species show a high initial root development, allowing seedlings to reach the moisture of deeper soil layers. In the present work seedlings of stone pine (Pinus pinea L.) and maritime pine (Pinus pinaster Ait.), were grown in culture solution supplied with 0.0, 0.1, 1 or 5 [mu]M CdSO[sub 4] or with 1 [mu]M CdSO[sub 4] and 1 [mu]M CuSO[sub 4] combined. In both species tap-root elongation was drastically reduced in the 5 [mu]M Cd[sup 2+] and in the (Cd[sup 2+] - Cu[sup 2+]) treatments. A supply of 0.1 or 1 [mu]M Cd[sup 2+] however, enhanced root elongation in Pinus pinea without significantly influencing root elongation in Pinus pinaster. In both species the root density (weight per unit length) and the width of the cortex increased in response to Cd[sup 2+] exposure. In Pinus pinaster the mitotic index decreased at the higher Cd[sup 2+] concentrations and when Cd[sup 2+] and Cu[sup 2+] were combined. The data suggest that cell elongation is more sensitive to Cd[sup 2+] than cell division. The number and length of the lateral roots were also affected by Cd[sup 2+] treatment to a higher degree in Pinus pinaster than in Pinus pinea, reflecting the different Cd-tolerance of the two species. (au)

  18. Fine root dynamics in moso bamboo and Japanese cedar forest by scanner method in central Taiwan

    Science.gov (United States)

    Chen, Zhi-Wei; Lin, Po-Hsuan; Kume, Tomonori

    2017-04-01

    Phyllostachys pubescens is one of the most important economic plant in the world. Phyllostachys pubescens originates from China and it had been introduced to neighbor countries about three hundred ago due to its economic value. But substantial bamboo forests were abandoned due to declines in demand. These unmanaged bamboo forests have been expanding to adjacent original forests in northern Taiwan. This vegetation alternation may not only decrease the local biodiversity but also affect the carbon cycle. Fine roots are responsible for water and nutrients acquisition and forming the most active part of the whole root system. The characteristics of fine roots are non-woody, small diameter and short lifespan. When roots keep producing new roots and replacing old roots, carbon and nutrients was transported into soil. Consequently, fine root production is one of the important component to understand the below-ground carbon cycle. However, there is few studies about fine root production in moso bamboo forests. We still lack effective method to obtain quantitative and objective data in Taiwan. It severely limits us to understand the below-ground carbon dynamics there. Minirhizotrons method has been used to investigate fine root dynamics by inserting transparent tubes into soil and by comparing changes in root length in images taken by micro-camera. But this method has some shortcomings; i.e. Most of image analysis are conducted manually and time-consuming. And it is difficult to estimate the stand level fine root production from small observation view. A new method "scanner method", which collect A4-size image (bigger than minirhizotrons) can overcome some parts of the shortcoming of minirhizotrons. The transparent acrylic box with A4-box view is inserted into soil and the interface between soil and box is scanned by commercial scanner. We can monitor the total projected root area, growth and decomposition separately by series of images. The primary objective of this study

  19. Clinical and imaging characteristics of foraminal nerve root disorders of the lumbar spine

    International Nuclear Information System (INIS)

    Nishi, Tomio; Tani, Takayuki; Suzuki, Norio; Aonuma, Hiroshi

    2009-01-01

    We analyzed cases of lumbar nerve root compression at intervertebral foramina, by comparing 19 cases of foraminal stenosis (FS), and 38 cases of foraminal hernia (FH) with 21 cases of lumbar canal stenosis (LCS). Japan Orthopedic Association (JOA) scores, intervertebral disc degeneration, anatomical measurements of the nerve root foramina and the MRI findings were reviewed. The scores for pain in the lower extremities, and walking ability were both lowest in the FS group. The scores for low back pain, lower extremities, and sensory disturbances were lowest in the FH group. Anterior-posterior diameters of the nerve root foramina were smaller in the FS group and FH group than in the LCS group. More degenerated discs and short length of upper part of the nerve root foramina were seen in FS group than in the other groups. The MRI images of so-called black out nerve root foramina were positive in 63.6% of FS cases, 75% of FH cases. (author)

  20. STORAGE TIME EFFECT ON MINI-CUTTINGS ROOTING IN Tectona grandis LINN F. CLONES

    Directory of Open Access Journals (Sweden)

    Yorleny Badilla

    2017-08-01

    Full Text Available ABSTRACT The study aimed to evaluate the influence of storage length on Tectona grandis mini-cuttings survival and rooting. A factorial arrangement (4 x 7 was utilized, based on four clones (Carapá, Ipê, GU5 and TB7 and seven time intervals from mini-cuttings harvesting until final sowing (0, 1, 2, 4, 8, 12 and 16 hours. A randomized block design with three replicates and 16 mini-cuttings per experimental unit was utilized. Survival and rooting rates were evaluated after greenhouse culture (30 days after sowing and after shadow house culture (40 days after sowing; as well as height, collar diameter, aerial and root biomass 55 days after sowing. No significant differences were observed in survival and rooting rates among time intervals in teak mini-cuttings preparation from these four clones. However differences among clones were registered for rooting rate, suggesting a genotypic effect. Survival and rooting rates were very high after greenhouse culture (93% and 90% respectively, as well as survival after culture in a shadow-house (88%.

  1. Iron absorption by roots of fruit plants : some characteristics of the phenomena

    International Nuclear Information System (INIS)

    Bindra, A.S.

    1979-01-01

    Using young plants of peach, plum and almond growing in water culture, study was undertaken on the absorption and translocation of labelled iron. When peach plants deficient in this element were supplied with it, they tended to absorb it very rapidly, especially during the first 30 minutes. This absorption was not a superficial adsorption. Iron absorption was found to be linked to the length of non-lignified roots. Of the three species, almond absorbed more iron than peach but less than olum. No significant varietal difference was found regarding the iron absorption capacity of roots of different varieties of peach. Removal of foliage did not influence the absorption of iron by roots of peach plants in the early stages. (auth.)

  2. Interspecies Interactions in Relation to Root Distribution Across the Rooting Profile in Wheat-Maize Intercropping Under Different Plant Densities

    Directory of Open Access Journals (Sweden)

    Yifan Wang

    2018-04-01

    Full Text Available In wheat-maize intercropping systems, the maize is often disadvantageous over the wheat during the co-growth period. It is unknown whether the impaired growth of maize can be recovered through the enhancement of the belowground interspecies interactions. In this study, we (i determined the mechanism of the belowground interaction in relation to root growth and distribution under different maize plant densities, and (ii quantified the “recovery effect” of maize after wheat harvest. The three-year (2014–2016 field experiment was conducted at the Oasis Agriculture Research Station of Gansu Agricultural University, Wuwei, Northwest China. Root weight density (RWD, root length density (RLD, and root surface area density (RSAD, were measured in single-cropped maize (M, single-cropped wheat (W, and three intercropping systems (i wheat-maize intercropping with no root barrier (i.e., complete belowground interaction, IC, (ii nylon mesh root barrier (partial belowground interaction, IC-PRI, and (iii plastic sheet root barrier (no belowground interaction, IC-NRI. The intercropped maize was planted at low (45,000 plants ha−1 and high (52,000 plants ha−1 densities. During the wheat/maize co-growth period, the IC treatment increased the RWD, RLD, and RSAD of the intercropped wheat in the 20–100 cm soil depth compared to the IC-PRI and IC-NRI systems; intercropped maize had 53% lower RWD, 81% lower RLD, and 70% lower RSAD than single-cropped maize. After wheat harvest, the intercropped maize recovered the growth with the increase of RWD by 40%, RLD by 44% and RSAD by 11%, compared to the single-cropped maize. Comparisons among the three intercropping systems revealed that the “recovery effect” of the intercropped maize was attributable to complete belowground interspecies interaction by 143%, the compensational effect due to root overlap by 35%, and the compensational effect due to water and nutrient exchange (CWN by 80%. The higher maize plant

  3. Intensive field phenotyping of maize (Zea mays L.) root crowns identifies phenes and phene integration associated with plant growth and nitrogen acquisition.

    Science.gov (United States)

    York, Larry M; Lynch, Jonathan P

    2015-09-01

    Root architecture is an important regulator of nitrogen (N) acquisition. Existing methods to phenotype the root architecture of cereal crops are generally limited to seedlings or to the outer roots of mature root crowns. The functional integration of root phenes is poorly understood. In this study, intensive phenotyping of mature root crowns of maize was conducted to discover phenes and phene modules related to N acquisition. Twelve maize genotypes were grown under replete and deficient N regimes in the field in South Africa and eight in the USA. An image was captured for every whorl of nodal roots in each crown. Custom software was used to measure root phenes including nodal occupancy, angle, diameter, distance to branching, lateral branching, and lateral length. Variation existed for all root phenes within maize root crowns. Size-related phenes such as diameter and number were substantially influenced by nodal position, while angle, lateral density, and distance to branching were not. Greater distance to branching, the length from the shoot to the emergence of laterals, is proposed to be a novel phene state that minimizes placing roots in already explored soil. Root phenes from both older and younger whorls of nodal roots contributed to variation in shoot mass and N uptake. The additive integration of root phenes accounted for 70% of the variation observed in shoot mass in low N soil. These results demonstrate the utility of intensive phenotyping of mature root systems, as well as the importance of phene integration in soil resource acquisition. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  4. Comparison of relationship between antral floor and maxillary root apex in bisecting and panoramic techniques

    International Nuclear Information System (INIS)

    You, Dong Soo; Kim, In Soo

    1986-01-01

    This study was performed to compare the difference of intraoral bisecting and panoramic techniques in evaluating the relationship of antral floor and maxillary roots. The vertical distances form maxillary root apices to antral floor were measured on both orthopantomograms and bisecting projections obtained form fifth subjects. The results were as follows: 1. Tooth lengths measured on orthopantomogram were larger than on bisecting projection and the magnification ratios were 1.08-1.17. 2. The dimensions from maxillary root apices to antral floor measured on orthopantomogram were larger than on bisecting projection. 3. The above results held true regardless of age and sex.

  5. Infection, Reproduction Potential, and Root Galling by Root-knot Nematode Species and Concomitant Populations on Peanut and Tobacco

    Science.gov (United States)

    Hirunsalee, Anan; Barker, K. R.; Beute, M. K.

    1995-01-01

    Single populations of Meloidogyne arenaria races 1 (MA1) and 2 (MA2) and M. hapla (MH), and mixed populations of MA1 + MA2 and MA1 + MH with four inoculum levels of eggs were tested on peanut cv. 'Florigiant' and M. incognita-resistant tobacco cv. 'McNair 373' in a greenhouse experiment. Root infection, female development, and reproduction of MA2 on peanut and MA1 on resistant tobacco were limited at 2 and 6 weeks. MA1, MH, and MA1 + MH on peanut had similar root infection (total parasitic forms per root unit) at both 2 and 6 weeks, and similar female development and reproduction potentials at 6 weeks. MA2 tended to depress root infection, female development, and reproduction of MA1 on peanut. MH had little effect on MA1 on this crop. On tobacco, MA2 population had greater incidence of root infection than did MH at 2 weeks. The two nematode species had similar development in roots at 6 weeks. All of these processes were restricted when either MA2 or MH was present together with MA1. As initial inoculum level of parasitically fit populations increased, relative infection ratio on both peanut and tobacco, and reproduction factor on peanut decreased. Populations that had high infection incidence and reproduction rates induced greater root galling than did other populations. Root galling was suppressed in the presence of antagonistic response between nematode populations. PMID:19277277

  6. The effect of photobiomodulation on root resorption during orthodontic treatment

    Directory of Open Access Journals (Sweden)

    Nimeri G

    2014-01-01

    Full Text Available Ghada Nimeri, Chung H Kau, Rachel Corona, Jeffery Shelly Department of Orthodontics, University of Alabama, Birmingham, AL, USA Abstract: Photobiomodulation is used to accelerate tooth movement during orthodontic treatments. The changes in root morphology in a group of orthodontic patients who received photobiomodulation were evaluated using the cone beam computed tomography technique. The device used is called OrthoPulse, which produces low levels of light with a near infrared wavelength of 850 nm and an intensity of 60 mW/cm2 continuous wave. Twenty orthodontic patients were recruited for these experiments, all with class 1 malocclusion and with Little's Irregularity Index (>2 mm in either of the arches. Root resorption was detected by measuring changes in tooth length using cone beam computed tomography. These changes were measured before the orthodontic treatment and use of low-level laser therapy and after finishing the alignment level. Little's Irregularity Index for all the patients was calculated in both the maxilla and mandible and patients were divided into three groups for further analysis, which were then compared to the root resorption measurements. Our results showed that photobiomodulation did not cause root resorption greater than the normal range that is commonly detected in orthodontic treatments. Furthermore, no correlation between Little's Irregularity Index and root resorption was detected. Keywords: photobiomodulation, root resorption, accelerate tooth movement, orthodontics, cone beam computed tomography

  7. Influence of Waterlogging on Carbohydrate Metabolism in Ragi and Rice Roots

    Directory of Open Access Journals (Sweden)

    Kulkarni, S. S.

    2013-04-01

    Full Text Available Effect of different durations of waterlogging (4, 8 and 12 days stress on carbohydrate status and activities of some related enzymes in ragi and rice roots was studied. In both ragi and rice roots there was decrease in starch and total sugar content in response to waterlogging conditions. Activity of α amylase was decrease in ragi roots while opposite trend was noticed in case of rice roots. The activity of pyruvate kinase was markedly increased due to 4, 8 and 12 days waterlogging in ragi roots while such increase was noticed in rice roots due to 12 days stress. Treatment of waterlogging caused enhancement in the activity of alkaline inorganic pyrophosphatase in the roots of both ragi and rice.

  8. Searching for plant root traits to improve soil cohesion and resist soil erosion

    Science.gov (United States)

    De Baets, Sarah; Smyth, Kevin; Denbigh, Tom; Weldon, Laura; Higgins, Ben; Matyjaszkiewicz, Antoni; Meersmans, Jeroen; Chenchiah, Isaac; Liverpool, Tannie; Quine, Tim; Grierson, Claire

    2017-04-01

    Soil erosion poses a serious threat to future food and environmental security. Soil erosion protection measures are therefore of great importance for soil conservation and food security. Plant roots have proven to be very effective in stabilizing the soil and protecting the soil against erosion. However, no clear insights are yet obtained into the root traits that are responsible for root-soil cohesion. This is important in order to better select the best species for soil protection. Research using Arabidopsis mutants has made great progress towards explaining how root systems are generated by growth, branching, and responses to gravity, producing mutants that affect root traits. In this study, the performance of selected Arabidopsis mutants is analyzed in three root-soil cohesion assays. Measurements of detachment, uprooting force and soil detachment are here combined with the microscopic analysis of root properties, such as the presence, length and density of root hairs in this case. We found that Arabidopsis seedlings with root hairs (wild type, wer myb23, rsl4) were more difficult to detach from gel media than hairless (cpc try) or short haired (rsl4, rhd2) roots. Hairy roots (wild type, wer myb23) on mature, non-reproductive rosettes were more difficult to uproot from compost or clay soil than hairless roots (cpc try). At high root densities, erosion rates from soils with hairless roots (cpc try) were as much as 10 times those seen from soils occupied by roots with hairs (wer myb23, wild type). We find therefore root hairs play a significant role in root-soil cohesion and in minimizing erosion. This framework and associated suite of experimental assays demonstrates its ability to measure the effect of any root phenotype on the effectiveness of plant roots in binding substrates and reducing erosion.

  9. Effects of total glucosides from paeony (Paeonia lactiflora Pall) roots on experimental atherosclerosis in rats.

    Science.gov (United States)

    Li, Jing; Chen, Chang Xun; Shen, Yun Hui

    2011-05-17

    Total glucosides of paeony (TGP), compounds extracted from the roots of Paeonia lactiflora Pall, have been used as an anti-inflammatory drug for the treatment of rheumatoid arthritis (RA) in China. Inflammation plays a critical role in the development of atherosclerotic vascular disease. Risk of cardiovascular diseases is significantly higher in patients with RA than in normal population. It has a great significance to study the effects of TGP on atherosclerosis. To investigate the effects of TGP on atherosclerosis induced by excessive administration of vitamin D and cholesterol in rats and study the mechanisms involved. Atherosclerosis was induced by excessive administration of vitamin D and cholesterol in rats. TGP was intragastrically administered for 15 weeks. The serum concentrations of total cholesterol (TC), triglyceride (TG), low density lipoprotein-cholesterol (LDL-C) and high density lipoprotein-cholesterol (HDL-C) were measured by automatic biochemistry analyzer. Apolipoprotein A1 (ApoA1) and apolipoprotein B (ApoB) were determined by immunoturbidimetry method, tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and C-reactive protein (CRP) were measured by enzyme-linked immunosorbent assay (ELISA) method. The morphological changes of aorta were observed with optical microscopy. Compared to controls, TGP significantly lowered the serum level of TC, TG, LDL-C, ApoB, TNF-alpha, IL-6 and CRP, increased the ratios of HDL-C/LDL-C and ApoA1/ApoB, decreased the intima-media thickness (IMT) of abdominal aortal wall and improved the morphological change of the aorta. TGP may attenuate the development of atherosclerotic disease. The beneficial effects are associated with its lowering blood lipids and inhibiting the expression of inflammatory cytokines. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  10. Study of external root resorption during orthodontic treatment in root filled teeth compared with their contralateral teeth with vital pulps.

    Science.gov (United States)

    Llamas-Carreras, J M; Amarilla, A; Solano, E; Velasco-Ortega, E; Rodríguez-Varo, L; Segura-Egea, J J

    2010-08-01

    To determine whether root filled teeth and those with vital pulps exhibit a similar degree of external root resorption (ERR) as a consequence of orthodontic treatment. The study sample consisted of 77 patients, with a mean age of 32.7 +/- 10.7 years, who had one root filled tooth before completion of multiband/bracket orthodontic therapy for at least 1 year. For each patient, digital panoramic radiographs taken before and after orthodontic treatment were used to determine the proportion of external root resorption (PRR), defined as the ratio between the root resorption in the root filled tooth and that in its contralateral tooth with a vital pulp. The student's t-test, anova and logistic regression analysis were used to determine statistical significance. The mean PRR was 1.00 +/- 0.13, indicating that, in the total sample, there were no significant differences in root resorption in the root filled teeth and their contralateral teeth with vital pulps. Multivariate logistic regression analysis suggested that PRR was significantly greater in incisors (P = 0.0014; odds ratio = 6.2885, C.I. 95% = 2.0-19.4), compared to other teeth, and in women (P = 0.0255; odds ratio = 4.2, C.I. 95% = 1.2-14.6), compared to men. There was no significant difference in the amount or severity of external root resorption during orthodontic movement between root filled teeth and their contralateral teeth with vital pulps.

  11. Effect of CO2 enhancement on beech (Fagus sylvatica L. seedling root rot due to Phytophthora plurivora and Phytophthora cactorum

    Directory of Open Access Journals (Sweden)

    Tkaczyk Miłosz

    2014-09-01

    Full Text Available Global climate change is associated with higher concentrations of atmospheric carbon dioxide (CO2. The ongoing changes are likely to have significant, direct or indirect effects on plant diseases caused by many biotic agents such as phytopathogenic fungi. This study results showed that increased CO2 concentration did not stimulate the growth of 1-year-old beech Fagus sylvatica L seedlings but it activated pathogenic Phytophthora species (P. plurivora and P. cactorum which caused significant reduction in the total number of fine roots as well as their length and area. The results of the greenhouse experiment indicated that pathogens once introduced into soil survived in pot soil, became periodically active (in sufficient water conditions and were able to damage beech fine roots. However, the trees mortality was not observed during the first year of experiment. DNA analyses performed on soil and beech tissue proved persistence of introduced Phytophthora isolates.

  12. Effect of day of the week of primary total hip arthroplasty on length of stay at a university-based teaching medical center.

    Science.gov (United States)

    Rathi, Pranav; Coleman, Sheldon; Durbin-Johnson, Blythe; Giordani, Mauro; Pereira, Gavin; Di Cesare, Paul E

    2014-12-01

    Length of hospital stay (LHS) after primary total hip arthroplasty (THA) constitutes a critical outcome measure, as prolonged LHS implies increased resource expenditure. Investigations have highlighted factors that affect LHS after THA. These factors include advanced age, medical comorbidities, obesity, intraoperative time, anesthesia technique, surgical site infection, and incision length. We retrospectively analyzed the effect of day of the week of primary THA on LHS. We reviewed the surgery and patient factors of 273 consecutive patients who underwent THA at our institution, a tertiary-care teaching hospital. There was a 15% increase in LHS for patients who underwent THA on Thursday versus Monday when controlling for other covariates that can affect LHS. Other statistically significant variables associated with increased LHS included American Society of Anesthesiologists grade, transfusion requirements, and postoperative complications. The day of the week of THA may be an independent variable affecting LHS. Institutions with reduced weekend resources may want to perform THA earlier in the week to try to reduce LHS.

  13. Radiographing roots and shoots

    International Nuclear Information System (INIS)

    Shariffah Noor Khamseah Al Idid

    1985-01-01

    The effect of seed orientation on germination time and on shoot and root growth patterns is studied. Neutron radiography is used to observe the development of 4 types of plants, maize, greenpea, soya bean and padi. These plants were grown in varying orientations; sand sizes, sand thicknesses, and level of water content. Radiography of the seeds and plants were obtained for time exposure ranging from 3-12 hours and at reactor thermal power level, ranging from 500-750 kilowatts. Results obtained showed that seeds planted in varying orientations need different length of time for shoot emergence. Neutron radiography is now developed to other areas of non-industrial applications in Malaysia. (A.J.)

  14. Root layering in a tropical forest after logging (Central Vietnam

    Directory of Open Access Journals (Sweden)

    Zdeněk Čermák

    2012-01-01

    Full Text Available Indigenous stands of tropical rain forests in the region of Kon Ha Nung are one of the most preserved forests in the whole Vietnam. Despite the logging activities mainly in the 1970’s, it was possible to preserve intact forests free from any primary harvesting. In the past, other stands were influenced by the logging to various extent. Some of those stands are managed presently; others were left to natural development. This paper deals with the influence of harvesting activities on the root system in forest stands. In primary stands and in stands with known harvest intensity, samples of root systems were collected. The total weight of dry basis and mainly their layering within the soil profile were assessed. The collected roots were divided into three classes: class I – ≤ 1.0 mm, class II 1.1–5.0 mm, class III – over 5.0 mm in the diameter. In the monitored plots, the total weight of dry basis of fine roots to 1.0 mm ranged from 2.34–3.24 t∙ha−1. The weight of dry basis of roots from 1.0–5.0 mm ranged from 6.57–9.69 t∙ha−1. The majority of roots of class I is presented in the top 10.0 cm of the soil and their share drops with the increasing depth. The roots of class II are distributed more equally. It was impossible to prove the influence of the logging on the root system.

  15. Regulation of root development in Arabidopsis thaliana by phytohormone-secreting epiphytic methylobacteria.

    Science.gov (United States)

    Klikno, Jana; Kutschera, Ulrich

    2017-09-01

    In numerous experimental studies, seedlings of the model dicot Arabidopsis thaliana have been raised on sterile mineral salt agar. However, under natural conditions, no plant has ever grown in an environment without bacteria. Here, we document that germ-free (gnotobiotic) seedlings, raised on mineral salt agar without sucrose, develop very short root hairs. In the presence of a soil extract that contains naturally occurring microbes, root hair elongation is promoted; this effect can be mimicked by the addition of methylobacteria to germ-free seedlings. Using five different bacterial species (Methylobacterium mesophilicum, Methylobacterium extorquens, Methylobacterium oryzae, Methylobacterium podarium, and Methylobacterium radiotolerans), we show that, over 9 days of seedling development in a light-dark cycle, root development (hair elongation, length of the primary root, branching patterns) is regulated by these epiphytic microbes that occur in the rhizosphere of field-grown plants. In a sterile liquid culture test system, auxin (IAA) inhibited root growth with little effect on hair elongation and significantly stimulated hypocotyl enlargement. Cytokinins (trans-zeatin, kinetin) and ethylene (application of the precursor ACC) likewise exerted an inhibitory effect on root growth but, in contrast to IAA, drastically stimulated root hair elongation. Methylobacteria are phytosymbionts that produce/secrete cytokinins. We conclude that, under real-world conditions (soil), the provision of these phytohormones by methylobacteria (and other epiphytic microbes) regulates root development during seedling establishment.

  16. Preventative Valve-Sparing Aortic Root Replacement and Pregnancy Outcome in Marfan Syndrome

    OpenAIRE

    Sokol, Vesna; Zlopaša, Gordan; Herman, Mislav; Planinić, Pavao; Micevska, Ana

    2012-01-01

    In Marfan syndrome, with dilatation of the aortic root secondary to an underlying connective tissue defect, pregnancy can cause hemodynamic stress leading to the development of an aortic aneurysm and even a fatal aortic dissection. In the presence of existing aortic root enlargement and a family history of aortic dissection, preventative elective surgery is suggested. Aortic root replacement with or without a valve-sparing procedure is superior to total aortic root replacement with ...

  17. Adaptive subdivision and the length and energy of Bézier curves

    DEFF Research Database (Denmark)

    Gravesen, Jens

    1997-01-01

    It is an often used fact that the control polygon of a Bézier curve approximates the curve and that the approximation gets better when the curve is subdivided. In particular, if a Bézier curve is subdivided into some number of pieces, then the arc-length of the original curve is greater than...... the sum of the chord-lengths of the pieces, and less than the sum of the polygon-lengths of the pieces. Under repeated subdivisions, the difference between this lower and upper bound gets arbitrarily small.If $L_c$ denotes the total chord-length of the pieces and $L_p$ denotes the total polygon...... combination, and it forms the basis for a fast adaptive algorithm, which determines the arc-length of a Bézier curve.The energy of a curve is half the square of the curvature integrated with respect to arc-length. Like in the case of the arc-length, it is possible to use the chord-length and polygon...

  18. Reciprocating vs Rotary Instrumentation in Pediatric Endodontics: Cone Beam Computed Tomographic Analysis of Deciduous Root Canals using Two Single-file Systems.

    Science.gov (United States)

    Prabhakar, Attiguppe R; Yavagal, Chandrashekar; Dixit, Kratika; Naik, Saraswathi V

    2016-01-01

    Primary root canals are considered to be most challenging due to their complex anatomy. "Wave one" and "one shape" are single-file systems with reciprocating and rotary motion respectively. The aim of this study was to evaluate and compare dentin thickness, centering ability, canal transportation, and instrumentation time of wave one and one shape files in primary root canals using a cone beam computed tomographic (CBCT) analysis. This is an experimental, in vitro study comparing the two groups. A total of 24 extracted human primary teeth with minimum 7 mm root length were included in the study. Cone beam computed tomographic images were taken before and after the instrumentation for each group. Dentin thickness, centering ability, canal transportation, and instrumentation times were evaluated for each group. A significant difference was found in instrumentation time and canal transportation measures between the two groups. Wave one showed less canal transportation as compared with one shape, and the mean instrumentation time of wave one was significantly less than one shape. Reciprocating single-file systems was found to be faster with much less procedural errors and can hence be recommended for shaping the root canals of primary teeth. How to cite this article: Prabhakar AR, Yavagal C, Dixit K, Naik SV. Reciprocating vs Rotary Instrumentation in Pediatric Endodontics: Cone Beam Computed Tomographic Analysis of Deciduous Root Canals using Two Single-File Systems. Int J Clin Pediatr Dent 2016;9(1):45-49.

  19. Root growth, secondary root formation and root gravitropism in carotenoid-deficient seedlings of Zea mays L

    Science.gov (United States)

    Ng, Y. K.; Moore, R.

    1985-01-01

    The effect of ABA on root growth, secondary-root formation and root gravitropism in seedlings of Zea mays was investigated by using Fluridone-treated seedlings and a viviparous mutant, both of which lack carotenoids and ABA. Primary roots of seedlings grown in the presence of Fluridone grew significantly slower than those of control (i.e. untreated) roots. Elongation of Fluridone-treated roots was inhibited significantly by the exogenous application of 1 mM ABA. Exogenous application of 1 micromole and 1 nmole ABA had either no effect or only a slight stimulatory effect on root elongation, depending on the method of application. The absence of ABA in Fluridone-treated plants was not an important factor in secondary-root formation in seedlings less than 9-10 d old. However, ABA may suppress secondary-root formation in older seedlings, since 11-d-old control seedlings had significantly fewer secondary roots than Fluridone-treated seedlings. Roots of Fluridone-treated and control seedlings were graviresponsive. Similar data were obtained for vp-9 mutants of Z. mays, which are phenotypically identical to Fluridone-treated seedlings. These results indicate that ABA is necessary for neither secondary-root formation nor for positive gravitropism by primary roots.

  20. Effect of microcystins on root growth, oxidative response, and exudation of rice (Oryza sativa).

    Science.gov (United States)

    Cao, Qing; Rediske, Richard R; Yao, Lei; Xie, Liqiang

    2018-03-01

    A 30 days indoor hydroponic experiment was carried out to evaluate the effect of microcystins (MCs) on rice root morphology and exudation, as well as bioaccumulation of MCs in rice. MCs were bioaccumulated in rice with the greatest concentrations being observed in the leaves (113.68μgg -1 Fresh weight (FW)) when exposed to 500μgL -1 MCs. Root activity at 500μgL -1 decreased 37%, compared to the control. MCs also induced disruption of the antioxidant system and lipid peroxidation in rice roots. Root growth was significantly inhibited by MCs. Root weight, length; surface area and volume were significantly decreased, as well as crown root number and lateral root number. After 30 days exposure to MCs, an increase was found in tartaric acid and malic acid while the other organic acids were not affected. Glycine, tyrosine, and glutamate were the only amino acids stimulated at MCs concentrations of 500μgL -1 . Similarly, dissolved organic carbon (DOC) and carbohydrate at 50 and 500μgL -1 treatments were significantly increased. The increase of DOC and carbohydrate in root exudates was due to rice root membrane permeability changes induced by MCs. Overall, this study indicated that MCs significantly inhibited rice root growth and affected root exudation. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. On the total number of genes and their length distribution in complete microbial genomes

    DEFF Research Database (Denmark)

    Skovgaard, Marie; Jensen, L.J.; Brunak, Søren

    2001-01-01

    In sequenced microbial genomes, some of the annotated genes are actually not protein-coding genes, but rather open reading frames that occur by chance. Therefore, the number of annotated genes is higher than the actual number of genes for most of these microbes. Comparison of the length...... distribution of the annotated genes with the length distribution of those matching a known protein reveals that too many short genes are annotated in many genomes. Here we estimate the true number of protein-coding genes for sequenced genomes. Although it is often claimed that Escherichia coli has about 4300...... genes, we show that it probably has only similar to 3800 genes, and that a similar discrepancy exists for almost all published genomes....

  2. The comparison between the length of vertical dimension of occlusion and the length of thumb on undergraduate Mongoloid students

    Directory of Open Access Journals (Sweden)

    Goh Li Teng

    2011-03-01

    Full Text Available The Thumb Rule of Leonardo da Vinci states that many proportions of the face show relationship with the length of thumb which is measured from the proximal tip of the proximal phalanx to the distal tip of the distal phalanx. Previous studies have shown that the length of the vertical dimension of occlusion (VDO is similar to the length of thumb of the Caucasoid race. The purpose of this study is to determine whether the length of VDO have correlations with the length of thumb among those of the Mongoloid race. This study took a survey method with the analytical cross-sectional approach. A total of 80 students of Faculty of Dentistry who have fulfilled all population criteria were randomly chosen to measure the length of VDO and the length of the thumb. Results analyzed with Student's t-test statistic revealed that there was a significant difference between males and females in the length of VDO and the length of the thumb, however, there was no significant difference between the length of VDO and the length of the thumb. There were very strong correlations (P<0.05 between the length of VDO and the length of the thumb. As a conclusion, the length of thumb can be suggested as an objective method to determine the length of VDO in this population.

  3. Root exudate-induced alterations in Bacillus cereus cell wall contribute to root colonization and plant growth promotion.

    Directory of Open Access Journals (Sweden)

    Swarnalee Dutta

    Full Text Available The outcome of an interaction between plant growth promoting rhizobacteria and plants may depend on the chemical composition of root exudates (REs. We report the colonization of tobacco, and not groundnut, roots by a non-rhizospheric Bacillus cereus (MTCC 430. There was a differential alteration in the cell wall components of B. cereus in response to the REs from tobacco and groundnut. Attenuated total reflectance infrared spectroscopy revealed a split in amide I region of B. cereus cells exposed to tobacco-root exudates (TRE, compared to those exposed to groundnut-root exudates (GRE. In addition, changes in exopolysaccharides and lipid-packing were observed in B. cereus grown in TRE-amended minimal media that were not detectable in GRE-amended media. Cell-wall proteome analyses revealed upregulation of oxidative stress-related alkyl hydroperoxide reductase, and DNA-protecting protein chain (Dlp-2, in response to GRE and TRE, respectively. Metabolism-related enzymes like 2-amino-3-ketobutyrate coenzyme A ligase and 2-methylcitrate dehydratase and a 60 kDa chaperonin were up-regulated in response to TRE and GRE. In response to B. cereus, the plant roots altered their exudate-chemodiversity with respect to carbohydrates, organic acids, alkanes, and polyols. TRE-induced changes in surface components of B. cereus may contribute to successful root colonization and subsequent plant growth promotion.

  4. Over-expression of mango (Mangifera indica L.) MiARF2 inhibits root and hypocotyl growth of Arabidopsis.

    Science.gov (United States)

    Wu, Bei; Li, Yun-He; Wu, Jian-Yong; Chen, Qi-Zhu; Huang, Xia; Chen, Yun-Feng; Huang, Xue-Lin

    2011-06-01

    An auxin response factor 2 gene, MiARF2, was cloned in our previous study [1] from the cotyledon section of mango (Mangifera indica L. cv. Zihua) during adventitious root formation, which shares an 84% amino acid sequence similarity to Arabidopsis ARF2. This study was to examine the effects of over-expression of the full-length MiARF2 open reading frame on the root and hypocotyl growth in Arabidopsis. Phenotype analysis showed that the T(3) transgenic lines had about 20-30% reduction in the length of hypocotyls and roots of the seedlings in comparison with the wild-type. The transcription levels of ANT and ARGOS genes which play a role in controlling organ size and cell proliferation in the transgenic seedlings also decreased. Therefore, the inhibited root and hypocotyl growth in the transgenic seedlings may be associated with the down-regulated transcription of ANT and ARGOS by the over-expression of MiARF2. This study also suggests that although MiARF2 only has a single DNA-binding domain (DBD), it can function as other ARF-like proteins containing complete DBD, middle region (MR) and carboxy-terminal dimerization domain (CTD).

  5. Enraizamento de microestacas de Lavandula angustifolia Rooting of Lavandula angustifolia microcuttings

    Directory of Open Access Journals (Sweden)

    Marília Pereira Machado

    2011-05-01

    Full Text Available A eliminação da etapa de enraizamento in vitro na micropropagação de plantas é desejável do ponto de vista econômico, além de proporcionar a melhoria na qualidade do sistema radicial formado. Dois experimentos foram realizados com os objetivos de avaliar diferentes concentrações (0; 2,5; 5,0 e 10mM de ácido indolbutírico (AIB no enraizamento ex vitro de lavanda (L. angustifolia, cv. 'Provence Blue' e avaliar a capacidade de enraizamento ex vitro das cultivares 'Vera', 'Provence Blue', 'English' e 'Elegance Ice'. Após 30 dias, foi avaliado o número de microestacas enraizadas, comprimento das raízes principais, porcentagem de enraizamento e porcentagem de sobrevivência. A concentração de 5,0mM de AIB foi mais efetiva para o comprimento de raízes e porcentagem de enraizamento das microestacas de lavanda cv. 'Provence Blue', apesar de reduzir o número de raízes formadas. Entre as cultivares estudadas, a porcentagem de sobrevivência das plantas variou de 82% a 100%. As cultivares apresentaram diferenças no enraizamento ex vitro das microestacas, sendo as maiores médias de porcentagem de enraizamento registradas na 'Provence Blue' e 'Elegance Ice'. Conclui-se que a microestaquia pode ser uma técnica eficiente para a propagação de lavanda, pelo tratamento das microestacas com 5,0mM de AIB, por proporcionar alta porcentagem de enraizamento e sobrevivência das plantas.Two experiments were carried out aiming to evaluate the ex vitro rooting of L. angustifolia cv. 'Provence Blue' treated with different concentrations (0, 2.5, 5.0 and 10mM of indolebutyric acid (IBA with talc as a vehicle to evaluated the ex vitro rooting of 'Vera', 'Provence Blue', 'English' and 'Elegance Ice' lavender cultivars. The experiments were carried out in a greenhouse using three concentrations of AIB plus control. After the 30th day, it was evaluated: surviving microcuttings percentage, percentage of rooted microcuttings, roots number, roots length

  6. A novel rat model of brachial plexus injury with nerve root stumps.

    Science.gov (United States)

    Fang, Jintao; Yang, Jiantao; Yang, Yi; Li, Liang; Qin, Bengang; He, Wenting; Yan, Liwei; Chen, Gang; Tu, Zhehui; Liu, Xiaolin; Gu, Liqiang

    2018-02-01

    The C5-C6 nerve roots are usually spared from avulsion after brachial plexus injury (BPI) and thus can be used as donors for nerve grafting. To date, there are no appropriate animal models to evaluate spared nerve root stumps. Hence, the aim of this study was to establish and evaluate a rat model with spared nerve root stumps in BPI. In rupture group, the proximal parts of C5-T1 nerve roots were held with the surrounding muscles and the distal parts were pulled by a sudden force after the brachial plexus was fully exposed, and the results were compared with those of sham group. To validate the model, the lengths of C5-T1 spared nerve root stumps were measured and the histologies of the shortest one and the corresponding spinal cord were evaluated. C5 nerve root stump was found to be the shortest. Histology findings demonstrated that the nerve fibers became more irregular and the continuity decreased; numbers and diameters of myelinated axons and thickness of myelin sheaths significantly decreased over time. The survival of motoneurons was reduced, and the death of motoneurons may be related to the apoptotic process. Our model could successfully create BPI model with nerve root stumps by traction, which could simulate injury mechanisms. While other models involve root avulsion or rupturing by distal nerve transection. This model would be suitable for evaluating nerve root stumps and testing new therapeutic strategies for neuroprotection through nerve root stumps in the future. Copyright © 2017. Published by Elsevier B.V.

  7. Allometric relations of total volumes of prolactin cells and corticotropic cells to body length in the annual cyprinodont Cynolebias whitei: effects of environmental salinity, stress and ageing

    NARCIS (Netherlands)

    Ruijter, J. M.; Wendelaar Bonga, S. E.

    1987-01-01

    An analysis of the allometric relations of the total volumes occupied by prolactin (PRL) and corticotropic (ACTH) cells (PRL volume and ACTH volume, respectively) to body length and a study of the immunocytochemical staining intensity of PRL and ACTH cells were used to determine the differences in

  8. Correlation Between Orthodontic Forces and Root Resorption – a Systematic Review of the Literature

    Directory of Open Access Journals (Sweden)

    Vlasa Alexandru

    2016-09-01

    Full Text Available Orthodontically induced external apical root resorption (OIEARR is a major concern regarding periodontal status after nonsurgical orthodontic treatment. The aim of this study was to assess this sequel by a systematic review of published data. For assessment, we performed an electronic search of one database for comprehensive data, using keywords in different combinations: “root resorption”, “periodontics” and “nonsurgical orthodontic treatment”. We supplemented the results searching by hand in published journals and we cross-referenced with the accessed articles. Patients included in the results presented a good general health status, with no previous history of OIEARR and no other associated pathologies. Finally, twenty-three studies were selected and included in this review. A high prevalence (69–98% and moderate severity of OIEARR (<5 mm and <1/3 from original root length were reported. No difference in root resorption was found regarding the sex of the patients. A moderate positive correlation between treatment duration and root resorption was found. Also, a mild correlation regarding antero-posterior apical displacement and root resorption was found.

  9. The effects of session length on demand functions generated using FR schedules.

    Science.gov (United States)

    Foster, T Mary; Kinloch, Jennifer; Poling, Alan

    2011-05-01

    In comparing open and closed economies, researchers often arrange shorter sessions under the former condition than under the latter. Several studies indicate that session length per se can affect performance and there are some data that indicate that this variable can influence demand functions. To provide further data, the present study exposed domestic hens to series of increasing fixed-ratio schedules with the length of the open-economy sessions varied over 10, 40, 60, and 120 min. Session time affected the total-session response rates and pause lengths. The shortest session gave the greatest response rates and shortest pauses and the longest gave the lowest response rates and longest pauses. The total-session demand functions also changed with session length: The shortest session gave steeper initial slopes (i.e., the functions were more elastic at small ratios) and smaller rates of change of elasticity than the longest session. Response rates, pauses, and demand functions were, however, similar for equivalent periods of responding taken from within sessions of different overall lengths (e.g., total-session data for 10-min sessions and the data for the first 10 min of 120-min sessions). These findings suggest that differences in session length can confound the results of studies comparing open and closed economies when those economies are arranged in sessions that differ substantially in length, hence data for equivalent-length periods of responding, rather than total-session data, should be of primary interest under these conditions.

  10. Effects of chicory root powder on growth performance and histomorphometry of jejunum in broiler chicks

    Directory of Open Access Journals (Sweden)

    Homan Izadi

    2013-09-01

    Full Text Available In the present study, chicory root powder (CRP as growth promoter at 1% and 3% levels was supplemented in broilers’ diet to investigate the growth performance and histo- morphometry of jejunum. One hundred twenty, one-day-old male broilers were used in a completely randomized design (CRD with 3 treatments and 4 replicates (10 chicks per replicate. At the end of each period (0-10, 11-24 and 0-24 days, feed intake (FI, weight gain (WG, and feed conversion ratio (FCR were measured. At the end of experiment (day 24, one bird per replicate was sacrificed for breast weight (BW, drumstick weight (DW, and jejunum length (JL as a percentage of body weight, and histomorphometry of villus. The FI increased by 3% CRP in the 1st period (p < 0.01. The percentage of WG significantly increased at 1% during the 1st period and, in the 2nd and total periods, it increased only at 3% CRP (p < 0.05. The FCR decreased at 1% in the 1st (p < 0.04 and, at 3% in the 2nd (p < 0.01 and total periods (p < 0.05. The percentage of DW increased at 3% CRP (p < 0.05. The treatments increased the percentage of BW (p < 0.059 and, percentage of JL (p < 0.079 as well. The villus width and, crypt depth (CD at 1% and 3% CRP and, villus surface at 3% reduced. The 3% CRP increased the villus length (VL and villi number (p < 0.05 and, VL/CD (p < 0.01 and, villus surface area (p < 0.02. The percentage of leaf-like villi decreased in CRP treatments (p < 0.05. The number of goblet cells increased in CRP treatments (p < 0.01. In conclusion, chicory root powder can improve growth performance in broilers by enhancing food digestion and absorption through modification of jejunum histomorphometry.

  11. Otolith Length-Fish Length Relationships of Eleven US Arctic Fish Species and Their Application to Ice Seal Diet Studies

    Science.gov (United States)

    Walker, K. L.; Norcross, B.

    2016-02-01

    The Arctic ecosystem has moved into the spotlight of scientific research in recent years due to increased climate change and oil and gas exploration. Arctic fishes and Arctic marine mammals represent key parts of this ecosystem, with fish being a common part of ice seal diets in the Arctic. Determining sizes of fish consumed by ice seals is difficult because otoliths are often the only part left of the fish after digestion. Otolith length is known to be positively related to fish length. By developing species-specific otolith-body morphometric relationships for Arctic marine fishes, fish length can be determined for fish prey found in seal stomachs. Fish were collected during ice free months in the Beaufort and Chukchi seas 2009 - 2014, and the most prevalent species captured were chosen for analysis. Otoliths from eleven fish species from seven families were measured. All species had strong linear relationships between otolith length and fish total length. Nine species had coefficient of determination values over 0.75, indicating that most of the variability in the otolith to fish length relationship was explained by the linear regression. These relationships will be applied to otoliths found in stomachs of three species of ice seals (spotted Phoca largha, ringed Pusa hispida, and bearded Erignathus barbatus) and used to estimate fish total length at time of consumption. Fish lengths can in turn be used to calculate fish weight, enabling further investigation into ice seal energetic demands. This application will aid in understanding how ice seals interact with fish communities in the US Arctic and directly contribute to diet comparisons among and within ice seal species. A better understanding of predator-prey interactions in the US Arctic will aid in predicting how ice seal and fish species will adapt to a changing Arctic.

  12. homo sapiens are bilaterally symmetrical but not with toe length and ...

    African Journals Online (AJOL)

    Kevin Ongeti

    2017-11-12

    Nov 12, 2017 ... in toe length and toe-length ratios among the three major ethnic groups in Nigeria. A total ... The toe-length ratios also displayed symmetrical differences for ... For the female population, all ratios were not significantly different.

  13. Protective effect of Asparagus racemosus root extract against lethal total - body electron beam radiation induced damage in Swiss albino mice

    International Nuclear Information System (INIS)

    Sharmila, K.P.; Bhandary, B. Satheesh Kumar; Suchetha Kumari, N.; Bhat, Vadish S.; Shetty, Jayaram; Peter, Alex John; Jose, Jerish M.; Fernandes, Ronald

    2016-01-01

    To investigate the protective effect of Asparagus Racemosus Root ethanolic extract (ARE) in Swiss albino mice against acute lethal total - body Electron beam irradiation. Swiss Albino mice were used for the assessment of radiation induced sickness and 30 day survival analysis. Survival studies were determined using the Kaplan-Meier survival curves. The maximum survival was observed in the experimental mice pretreated with 200 mg/kg.b.wt. of ARE which also reduced the radiation sickness characteristics. This dose was considered as an optimal dose for radioprotection. Treatment of mice with ARE before irradiation delayed the onset of mortality as compared with the untreated irradiated controls. Present findings demonstrate the potential of ARE in mitigating radiation-induced mortality, which may be attributed to its free radical scavenging and increased antioxidant potential

  14. Comparing simple root phenotyping methods on a core set of rice genotypes.

    Science.gov (United States)

    Shrestha, R; Al-Shugeairy, Z; Al-Ogaidi, F; Munasinghe, M; Radermacher, M; Vandenhirtz, J; Price, A H

    2014-05-01

    Interest in belowground plant growth is increasing, especially in relation to arguments that shallow-rooted cultivars are efficient at exploiting soil phosphorus while deep-rooted ones will access water at depth. However, methods for assessing roots in large numbers of plants are diverse and direct comparisons of methods are rare. Three methods for measuring root growth traits were evaluated for utility in discriminating rice cultivars: soil-filled rhizotrons, hydroponics and soil-filled pots whose bottom was sealed with a non-woven fabric (a potential method for assessing root penetration ability). A set of 38 rice genotypes including the OryzaSNP set of 20 cultivars, additional parents of mapping populations and products of marker-assisted selection for root QTLs were assessed. A novel method of image analysis for assessing rooting angles from rhizotron photographs was employed. The non-woven fabric was the easiest yet least discriminatory method, while the rhizotron was highly discriminatory and allowed the most traits to be measured but required more than three times the labour of the other methods. The hydroponics was both easy and discriminatory, allowed temporal measurements, but is most likely to suffer from artefacts. Image analysis of rhizotrons compared favourably to manual methods for discriminating between cultivars. Previous observations that cultivars from the indica subpopulation have shallower rooting angles than aus or japonica cultivars were confirmed in the rhizotrons, and indica and temperate japonicas had lower maximum root lengths in rhizotrons and hydroponics. It is concluded that rhizotrons are the preferred method for root screening, particularly since root angles can be assessed. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

  15. The Effect of Polyamine Applications on Root Enhancement of Pistachio Seedling Rootstocks of ‘Badamy-E- Riz’

    Directory of Open Access Journals (Sweden)

    S. Sedaghat

    2014-02-01

    Full Text Available Pistacia vera cv Badami-e-Riz is the most important and popular rootstock in Iran, which tolerate salinity soil and phytophthora fungi but its root is less affected. In addition this rootstock is susceptible to excessive B and water deficient. This rootstock has a taproot rooting system without any lateral root. So this study was conducted to evaluate the effects of various concentrations and application methods of polyamines on root regeneration of transplanted bare-rooted ‘Badami-e-Riz’ pistachio rootstocks.The result showed that spermidine at concentration of 2 mM as foliar application method significantly enhanced root length and root diameter in ‘Badami-e-Riz’. Furthermore, the fresh weight of root was increased by 4 mM spermidine by foliar application and 2 mM spermidine by interaction of root tip cut and root dip method, significantly increased dry weight of root and root number in ‘Badami-e-Riz’. Besides, by the use of these chemicals, the survival percentage of seedlings was maintained in higher value. Results suggested that polyamine application was effective to increase lateral root formation and improved root regeneration. Therefore, it would be useful to help the survival of seedlings following transplanting.

  16. Root carbon input in organic and inorganic fertilizer-based systems

    DEFF Research Database (Denmark)

    Chirinda, Ngoni; Olesen, Jørgen E; Porter, John

    2012-01-01

    C input to remain scant. This study aimed at determining macro-root C input and topsoil root related respiration in response to nutrient management and soil fertility building measures. Methods We sampled roots and shoots of cereals and catch crops in inorganic and organic fertilizer-based arable...... season of winter wheat by subtracting soil respiration from soil with and without exclusion of roots. Results Catch crop roots accounted for more than 40 % of total plant C. For spring barley in 2008 and spring wheat in 2010, root C was higher in the organic than in the inorganic fertilizer-based systems...... was higher (31–131 %) in inorganic than in organic fertilizer-based systems. Conclusions Our findings show that macro-roots of both cereal crops and catch crops play a relatively larger role in organically managed systems than in mineral fertilizer based systems; and that the use of fixed biomass S/R ratios...

  17. Standardized Total Tract Digestibility of Phosphorus in Copra Expellers, Palm Kernel Expellers, and Cassava Root Fed to Growing Pigs

    Directory of Open Access Journals (Sweden)

    A. R. Son

    2013-11-01

    Full Text Available An experiment was conducted to determine the apparent total tract digestibility (ATTD and standardized total tract digestibility (STTD of phosphorus (P in copra expellers (CE, palm kernel expellers (PKE, and cassava root (CR. Eight barrows (initial BW of 40.0 kg, SD = 4.5 were individually housed in metabolism crates. A replicated 4×3 incomplete Latin square design was employed involving 4 dietary treatments, 3 periods, and 8 animals. Three experimental diets contained 40% CE, PKE or CR as the only source of P. A P-free diet mainly based on corn starch, sucrose, and gelatin was also prepared to estimate the basal endogenous loss of P. The marker-to-marker method was used for fecal collection. Values for the ATTD of P in the CE and PKE were greater than in the CR (46.0 and 39.7 vs −14.0%; p<0.05. However, the STTD of P did not differ greatly among the test ingredients (56.5, 49.0, and 43.2% in the CE, PKE, and CR, respectively. In conclusion, the ATTD of P values in CE and PKE were greater than that in CR, but the STTD of P did not differ greatly among CE, PKE, and CR.

  18. Soil and Root Respiration Under Elevated CO2 Concentrations During Seedling Growth of Pinus sylvestris var. sylvestriformis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The objectives of this study were to investigate the effect of higher CO2 concentrations (500 and 700 μmol mol-1) in atmosphere on total soil respiration and the contribution of root respiration to total soil respiration during seedling growth of Pinus sylvestris var. sylvestriformis. During the four growing seasons (May-October) from 1999 to 2003, the seedlings were exposed to elevated concentrations of CO2 in open-top chambers. The total soil respiration and contribution of root respiration were measured using an LI-6400-09 soil CO2 flux chamber on June 15 and October 8, 2003. To separate root respiration from total soil respiration, three PVC cylinders were inserted approximately 30 cm deep into the soil in each chamber. There were marked diurnal changes in air and soil temperatures on June 15. Both the total soil respiration and the soil respiration without roots showed a strong diurnal pattern, increasing from before sunrise to about 14:00in the afternoon and then decreasing before the next sunrise. No increase in the mean total soil respiration and mean soil respiration with roots severed was observed under the elevated CO2 treatments on June 15, 2003, as compared to the open field and control chamber with ambient CO2. However, on October 8, 2003, the total soil respiration and soil respiration with roots severed in the open field were lower than those in the control and elevated CO2 chambers. The mean contribution of root respiration measured on June 15, 2003, ranged from 8.3% to 30.5% and on October 8, 2003,from 20.6% to 48.6%.

  19. Detailed analysis of the blade root flow of a horizontal axis wind turbine

    Directory of Open Access Journals (Sweden)

    I. Herráez

    2016-07-01

    Full Text Available The root flow of wind turbine blades is subjected to complex physical mechanisms that influence significantly the rotor aerodynamic performance. Spanwise flows, the Himmelskamp effect, and the formation of the root vortex are examples of interrelated aerodynamic phenomena that take place in the blade root region. In this study we address those phenomena by means of particle image velocimetry (PIV measurements and Reynolds-averaged Navier–Stokes (RANS simulations. The numerical results obtained in this study are in very good agreement with the experiments and unveil the details of the intricate root flow. The Himmelskamp effect is shown to delay the stall onset and to enhance the lift force coefficient Cl even at moderate angles of attack. This improvement in the aerodynamic performance occurs in spite of the negative influence of the mentioned effect on the suction peak of the involved blade sections. The results also show that the vortex emanating from the spanwise position of maximum chord length rotates in the opposite direction to the root vortex, which affects the wake evolution. Furthermore, the aerodynamic losses in the root region are demonstrated to take place much more gradually than at the tip.

  20. Localized iron supply triggers lateral root elongation in Arabidopsis by altering the AUX1-mediated auxin distribution.

    Science.gov (United States)

    Giehl, Ricardo F H; Lima, Joni E; von Wirén, Nicolaus

    2012-01-01

    Root system architecture depends on nutrient availability, which shapes primary and lateral root development in a nutrient-specific manner. To better understand how nutrient signals are integrated into root developmental programs, we investigated the morphological response of Arabidopsis thaliana roots to iron (Fe). Relative to a homogeneous supply, localized Fe supply in horizontally separated agar plates doubled lateral root length without having a differential effect on lateral root number. In the Fe uptake-defective mutant iron-regulated transporter1 (irt1), lateral root development was severely repressed, but a requirement for IRT1 could be circumvented by Fe application to shoots, indicating that symplastic Fe triggered the local elongation of lateral roots. The Fe-stimulated emergence of lateral root primordia and root cell elongation depended on the rootward auxin stream and was accompanied by a higher activity of the auxin reporter DR5-β-glucuronidase in lateral root apices. A crucial role of the auxin transporter AUXIN RESISTANT1 (AUX1) in Fe-triggered lateral root elongation was indicated by Fe-responsive AUX1 promoter activities in lateral root apices and by the failure of the aux1-T mutant to elongate lateral roots into Fe-enriched agar patches. We conclude that a local symplastic Fe gradient in lateral roots upregulates AUX1 to accumulate auxin in lateral root apices as a prerequisite for lateral root elongation.

  1. Morphological Changes Of The Root Surface And Fracture Resistance After Treatment Of Root Fracture By CO2 Laser And Glass Ionomer Or Mineral Trioxide Aggregates

    Science.gov (United States)

    Badr, Y. A.; Abd El-Gawad, L. M.; Ghaith, M. E.

    2009-09-01

    This in vitro study evaluates the morphological changes of the root surface and fracture resistance after treatment of root cracks by CO2 laser and glass Ionomer or mineral trioxide aggregates (MTA). Fifty freshly extracted human maxillary central incisor teeth with similar dimension were selected. Crowns were sectioned at the cemento-enamel junction, and the lengths of the roots were adjusted to 13 mm. A longitudinal groove with a dimension of 1×5 mm2 and a depth of 1.5 mm was prepared by a high speed fissure bur on the labial surface of the root. The roots were divided into 5 groups: the 10 root grooves in group 1 were remained unfilled and were used as a control group. The 10 root grooves in group 2 were filled with glass Ionomer, 10 root grooves in group 3 were filled with MTA, the 10 root grooves in group 4 were filled with glass Ionomer and irradiated by CO2 laser and the 10 root grooves in group 5 were filled with MTA and irradiated with CO2 laser. Scanning electron microscopy was performed for two samples in each group. Tests for fracture strength were performed using a universal testing machine and a round tip of a diameter of 4 mm. The force was applied vertically with a constant speed of 1 mm min 1. For each root, the force at the time of fracture was recorded in Newtons. Results were evaluated statistically with ANOVA and Turkey's Honestly Significant Difference (HSD) tests. SEM micrographs revealed that the melted masses and the plate-like crystals formed a tight Chemical bond between the cementum and glass Ionomer and melted masses and globular like structure between cementum and MTA. The mean fracture resistance was the maximum fracture resistance in group 5 (810.8 N). Glass Ionomer and MTA with the help of CO2 laser can be an alternative to the treatment of tooth crack or fracture. CO2 laser increase the resistance of the teeth to fracture.

  2. The relationship between profiles of plagiogravitropism and morphometry of columella cells during the development of lateral roots of Vigna angularis

    Science.gov (United States)

    Kuya, Noriyuki; Sato, Seiichi

    2011-02-01

    There has been no convincing explanation on a mechanism inducing plagiogravitropism of lateral roots. The present work deals with gravitropic features of Vignaangularis lateral roots during the course of their growth and morphometric analysis of root caps, columella cells and amyloplasts. Regardless of the magnitude of deviation of the primary root axis from the gravity vector, the newly emerging lateral roots tended to keep a constant angle to the gravity vector. They modified gravireaction several times during the course of their development: a first horizontal-growth stage when they grow in the cortex of primary roots (stage I), a sloping-down growth stage from their emergence to a length of about 1 mm (stage II), a second horizontal-growth stage from a length of about 1 mm to that of over 4 mm (stage III) and a curving-down stage thereafter (stage IV). The columella cells with amyloplasts large enough to sediment were not fully differentiated in the stage I but the turning point from the stage I to II was associated with the development of amyloplasts which were able to sediment toward the distal part of the cell. Amyloplasts were significantly small in the lateral roots over 10 mm long compared with those in ones 0-10 mm long, suggesting that they rapidly develop immediately after the lateral roots emerge from primary roots and then gradually decrease their size when the lateral roots grow over 10 mm long. This dimensional decrease of amyloplasts may be partially involved in weak gravireaction in the stage III. Evidence was not presented indicating that a switchover from the stage III to IV was connected with the dimension of root caps, the number of columella cells and the development of amyloplasts. Some factors at the molecular level rather than at the cellular and tissue levels are probably dominant to induce the stage IV.

  3. Competition between Plant-Populations with Different Rooting Depths. 2. Pot Experiments

    NARCIS (Netherlands)

    Berendse, F.

    1981-01-01

    In a previous paper in this series a model was proposed lor the competition between plant populations with different rooting depths. This model predicts that in mixtures of plant populations with different rooting depths the Relative Yield Total will exceed unity. Secondly it predicts that in these

  4. Competition between Plant-Populations with Different Rooting Depths. 1. Theoretical Considerations

    NARCIS (Netherlands)

    Berendse, F.

    1979-01-01

    As an extension of De Wit's competition theory a theoretical description has been developed of competition between plant populations with different rooting depths. This model shows that in mixtures of plants with different rooting depths the value of the Relative Yield Total can be expected to

  5. Competition Between Plant Populations with Different Rooting Depths I. Theoretical Considerations

    NARCIS (Netherlands)

    Berendse, Frank

    1979-01-01

    As an extension of De Wit’s competition theory a theoretical description has been developed of competition between plant populations with different rooting depths. This model shows that in mixtures of plants with different rooting depths the value of the Relative Yield Total can be expected to

  6. Three-dimensional anatomy of equine incisors: tooth length, enamel cover and age related changes

    Science.gov (United States)

    2013-01-01

    Background Equine incisors are subjected to continuous occlusal wear causing multiple, age related changes of the extragingival crown. It is assumed that the occlusal wear is compensated by continued tooth elongation at the apical ends of the teeth. In this study, μCT-datasets offered the opportunity to analyze the three-dimensional appearance of the extra- and intraalveolar parts of the enamel containing dental crown as well as of the enamel-free dental root. Multiple morphometric measurements elucidated age related, morphological changes within the intraalveolar part of the incisors. Results Equine incisors possess a unique enamel cover displaying large indentations on the mesial and distal sides. After eruption tooth elongation at the apical end outbalances occlusal wear for two to four years resulting in increasing incisor length in this period of time. Remarkably, this maximum length is maintained for about ten years, up to a tooth age of 13 to 15 years post eruption. Variances in the total length of individual teeth are related to different Triadan positions (central-, middle- and corner incisors) as well as to the upper and lower arcades. Conclusion Equine incisors are able to fully compensate occlusal wear for a limited period of time. However, after this ability ceases, it is expected that a diminished intraalveolar tooth length will cause massive changes in periodontal biomechanics. The time point of these morphodynamic and biomechanical changes (13 to 15 years post eruption) occurs in coincidence with the onset of a recently described destructive disease of equine incisor (equine odontoclastic tooth resorption and hypercementosis) in aged horses. However, further biomechanical, cell biological and microbiological investigations are needed to elucidate a correlation between age related changes of incisor morphology and this disease. PMID:24321365

  7. Endodontic treatment of mandibular molar with root dilaceration using Reciproc single-file system.

    Science.gov (United States)

    Meireles, Daniely Amorin; Bastos, Mariana Mena Barreto; Marques, André Augusto Franco; Garcia, Lucas da Fonseca Roberti; Sponchiado, Emílio Carlos

    2013-08-01

    Biomechanical preparation of root canals with accentuated curvature is challenging. New rotatory systems, such as Reciproc, require a shorter period of time to prepare curved canals, and became a viable alternative for endodontic treatment of teeth with root dilaceration. Thus, this study aimed to report a clinical case of endodontic therapy of root with accentuated dilaceration using Reciproc single-file system. Mandibular right second molar was diagnosed as asymptomatic irreversible pulpitis. Pulp chamber access was performed, and glide path was created with #10 K-file (Dentsply Maillefer) and PathFile #13, #16 and #19 (Dentsply Maillefer) up to the temporary working length. The working length measured corresponded to 20 mm in the mesio-buccal and mesio-lingual canals, and 22 mm in the distal canal. The R25 file (VDW GmbH) was used in all the canals for instrumentation and final preparation, followed by filling with Reciproc gutta-percha cones (VDW GmbH) and AH Plus sealer (Dentsply Maillefer), using thermal compaction technique. The case has been receiving follow-up for 6 mon and no painful symptomatology or periapical lesions have been found. Despite the difficulties, the treatment could be performed in a shorter period of time than the conventional methods.

  8. Rooting in vitro of zygotic embryos of Acrocomia aculeata (Jacq. Lodd ex Mart.

    Directory of Open Access Journals (Sweden)

    Carlos Fiori Fernández

    2016-01-01

    Full Text Available Acrocomia aculeata is a potential specie for the energy industry, however, the latency in its seeds delay germination, affecting performance. The experiment was performed in the Biology Laboratory of the Faculty of Agricultural Sciences of the National University of Asunción; the objective was to establish a protocol for zygotic embryogenesis and rooting of this species. A completely randomized design was used, applying Kruskal-Wallis and Mann-Whitney test with 5% error probability, subject to verification of assumptions of distribution The treatments consisted of MS medium (Murashige and Skoog supplemented with benzylaminopurine (BAP of 1, 2 and 4 ppm, MS medium with 2 g/L of active carbon (AC and simple MS mediums. 45 zygotic embryos were initially cultivated on MS medium supplemented with 2 g/L of AC and exposed to initial darkness for 20 days, then subcultured in the mentioned treatments. Root length was the measured variable, assessed in two periods of 20 days. There was no significant effects in the treatments with BAP, the CA suppressed explants oxidation; whereas the best results showed treatments 1 (MS + 1 ppm BAP and 4 (MS + CA 2g/L with 6 and 5 cm of root length respectively, after 40 incubation days.

  9. Endodontic treatment of mandibular molar with root dilaceration using Reciproc single-file system

    Directory of Open Access Journals (Sweden)

    Daniely Amorin Meireles

    2013-08-01

    Full Text Available Biomechanical preparation of root canals with accentuated curvature is challenging. New rotatory systems, such as Reciproc, require a shorter period of time to prepare curved canals, and became a viable alternative for endodontic treatment of teeth with root dilaceration. Thus, this study aimed to report a clinical case of endodontic therapy of root with accentuated dilaceration using Reciproc single-file system. Mandibular right second molar was diagnosed as asymptomatic irreversible pulpitis. Pulp chamber access was performed, and glide path was created with #10 K-file (Dentsply Maillefer and PathFile #13, #16 and #19 (Dentsply Maillefer up to the temporary working length. The working length measured corresponded to 20 mm in the mesio-buccal and mesio-lingual canals, and 22 mm in the distal canal. The R25 file (VDW GmbH was used in all the canals for instrumentation and final preparation, followed by filling with Reciproc gutta-percha cones (VDW GmbH and AH Plus sealer (Dentsply Maillefer, using thermal compaction technique. The case has been receiving follow-up for 6 mon and no painful symptomatology or periapical lesions have been found. Despite the difficulties, the treatment could be performed in a shorter period of time than the conventional methods.

  10. The effect of ovalbumin on orthodontic induced root resorption

    Directory of Open Access Journals (Sweden)

    Hosseinagha Aghili

    2013-01-01

    Full Text Available Background: This randomized trial was undertaken to investigate the effect of experimentally induced allergy on orthodontic induced root resorption. Materials and Methods: A total of 30 Wistar rats were divided randomly into test and control groups. Starting from the first 3 days, the rats in the test group were injected intra-peritoneally by 2 mg ovalbumin as allergen and 0.5 mg Alume as adjuvant. Afterward only allergen was injected once a week. The control group was injected by normal saline. After 21 days, Wistar immunoglobulin E was measured and peripheral matured eosinophil was counted. A total of 50 g nickel-titanium closed coil spring was ligated between right incisor and first molar. All animals were sacrificed after 14 days. The mesial root of the right and left first molar was dissected in a horizontal plane. The specimens were divided into four groups considering whether force and/or ovalbumin was applied or not. Root resorption was measured and compared among these groups. Repeated measures analysis of variance (ANOVA, and Bonferoni tests were used to analyze the data. The level of significance was determined at 0.05. Results: In general, the differences were insignificant (P > 0.05. As the only exception, the group in which both ovalbumin and force were applied had significantly more root resorption than the group in which neither force nor ovalbumin was applied (P < 0.001. Conclusion: Allergy may increase the susceptibility to root resorption. Application of light force, periodical monitoring of root resorption and control of allergy are advisable.

  11. ASSESSMENT OF ROOT RESORPTION DEGREE OF INCISORS AFTER ORTHODONTIC TREATMENT IN ADULTS

    Directory of Open Access Journals (Sweden)

    I. Luchian

    2012-03-01

    Full Text Available The main iatrogenic effects associated with orthodontic treatment refer to: influence of orthodontic rings on the periodontal tissue; gum retractions; the effect of the orthodontic treatment on dental root (root resorption; the effect of the orthodontic treatment on alveolar bone height; mobility and pain associated with orthodontic treatment. AIM of the study: To assess the degree of root resorption of incisors, after orthodontic treatment, on a group of 48 adults with dental-maxillary abnormalities. Materials and method: The study included 48 young adult patients, 35 women and 13 men aged 18 to 30 years, who had received fixed orthodontic treatment. To assess the degree of root resorption (changes at root level and apical contour length, apical radiographies were taken in the maxillary incisors and jaw both at the beginning and end of the orthodontic treatment. Results: Out of the 239 incisors examined at the beginning of orthodontic treatment, 163 showed code 0, meaning 88.1%, and 50 showed a slight squash apex (code 1, respectively 10.9%. Only 1% of all incisors assessed presented mild and severe root resorption. Conclusions: The results of the study show that, generally, an adult orthodontic treatment, applied for functional and aesthetic objectives, may have clinically acceptable iatrogenic effects.

  12. Minimum variance rooting of phylogenetic trees and implications for species tree reconstruction.

    Science.gov (United States)

    Mai, Uyen; Sayyari, Erfan; Mirarab, Siavash

    2017-01-01

    Phylogenetic trees inferred using commonly-used models of sequence evolution are unrooted, but the root position matters both for interpretation and downstream applications. This issue has been long recognized; however, whether the potential for discordance between the species tree and gene trees impacts methods of rooting a phylogenetic tree has not been extensively studied. In this paper, we introduce a new method of rooting a tree based on its branch length distribution; our method, which minimizes the variance of root to tip distances, is inspired by the traditional midpoint rerooting and is justified when deviations from the strict molecular clock are random. Like midpoint rerooting, the method can be implemented in a linear time algorithm. In extensive simulations that consider discordance between gene trees and the species tree, we show that the new method is more accurate than midpoint rerooting, but its relative accuracy compared to using outgroups to root gene trees depends on the size of the dataset and levels of deviations from the strict clock. We show high levels of error for all methods of rooting estimated gene trees due to factors that include effects of gene tree discordance, deviations from the clock, and gene tree estimation error. Our simulations, however, did not reveal significant differences between two equivalent methods for species tree estimation that use rooted and unrooted input, namely, STAR and NJst. Nevertheless, our results point to limitations of existing scalable rooting methods.

  13. Genome-Wide Association Study for Traits Related to Plant and Grain Morphology, and Root Architecture in Temperate Rice Accessions.

    Science.gov (United States)

    Biscarini, Filippo; Cozzi, Paolo; Casella, Laura; Riccardi, Paolo; Vattari, Alessandra; Orasen, Gabriele; Perrini, Rosaria; Tacconi, Gianni; Tondelli, Alessandro; Biselli, Chiara; Cattivelli, Luigi; Spindel, Jennifer; McCouch, Susan; Abbruscato, Pamela; Valé, Giampiero; Piffanelli, Pietro; Greco, Raffaella

    2016-01-01

    In this study we carried out a genome-wide association analysis for plant and grain morphology and root architecture in a unique panel of temperate rice accessions adapted to European pedo-climatic conditions. This is the first study to assess the association of selected phenotypic traits to specific genomic regions in the narrow genetic pool of temperate japonica. A set of 391 rice accessions were GBS-genotyped yielding-after data editing-57000 polymorphic and informative SNPS, among which 54% were in genic regions. In total, 42 significant genotype-phenotype associations were detected: 21 for plant morphology traits, 11 for grain quality traits, 10 for root architecture traits. The FDR of detected associations ranged from 3 · 10-7 to 0.92 (median: 0.25). In most cases, the significant detected associations co-localised with QTLs and candidate genes controlling the phenotypic variation of single or multiple traits. The most significant associations were those for flag leaf width on chromosome 4 (FDR = 3 · 10-7) and for plant height on chromosome 6 (FDR = 0.011). We demonstrate the effectiveness and resolution of the developed platform for high-throughput phenotyping, genotyping and GWAS in detecting major QTLs for relevant traits in rice. We identified strong associations that may be used for selection in temperate irrigated rice breeding: e.g. associations for flag leaf width, plant height, root volume and length, grain length, grain width and their ratio. Our findings pave the way to successfully exploit the narrow genetic pool of European temperate rice and to pinpoint the most relevant genetic components contributing to the adaptability and high yield of this germplasm. The generated data could be of direct use in genomic-assisted breeding strategies.

  14. Genome-Wide Association Study for Traits Related to Plant and Grain Morphology, and Root Architecture in Temperate Rice Accessions.

    Directory of Open Access Journals (Sweden)

    Filippo Biscarini

    Full Text Available In this study we carried out a genome-wide association analysis for plant and grain morphology and root architecture in a unique panel of temperate rice accessions adapted to European pedo-climatic conditions. This is the first study to assess the association of selected phenotypic traits to specific genomic regions in the narrow genetic pool of temperate japonica. A set of 391 rice accessions were GBS-genotyped yielding-after data editing-57000 polymorphic and informative SNPS, among which 54% were in genic regions.In total, 42 significant genotype-phenotype associations were detected: 21 for plant morphology traits, 11 for grain quality traits, 10 for root architecture traits. The FDR of detected associations ranged from 3 · 10-7 to 0.92 (median: 0.25. In most cases, the significant detected associations co-localised with QTLs and candidate genes controlling the phenotypic variation of single or multiple traits. The most significant associations were those for flag leaf width on chromosome 4 (FDR = 3 · 10-7 and for plant height on chromosome 6 (FDR = 0.011.We demonstrate the effectiveness and resolution of the developed platform for high-throughput phenotyping, genotyping and GWAS in detecting major QTLs for relevant traits in rice. We identified strong associations that may be used for selection in temperate irrigated rice breeding: e.g. associations for flag leaf width, plant height, root volume and length, grain length, grain width and their ratio. Our findings pave the way to successfully exploit the narrow genetic pool of European temperate rice and to pinpoint the most relevant genetic components contributing to the adaptability and high yield of this germplasm. The generated data could be of direct use in genomic-assisted breeding strategies.

  15. Different Phylogenetic and Environmental Controls of First-order Root Morphological and Chemical Traits

    Science.gov (United States)

    Wang, R.; Wang, Q.; Zhao, N.; Yu, G.; He, N.

    2017-12-01

    Fine roots are the most distal roots that act as the primary belowground organs in acquiring limiting nutrients and water from the soil. However, limited by the inconsistency in definitions of fine roots and the different protocols among studies, knowledge of root system traits has, to date, still lagged far behind our understanding of above-ground traits. In particular, whether variation in fine root traits among the plant species along a single root economics spectrum and this underlying mechanism are still hotly debated. In this study, we sampled the first-order root using the standardized protocols, and measured six important root traits related to resource use strategies, from 181 plant species from subtropical to boreal forests. Base on this large dataset, we concluded that different phylogenetic and environmental factors affected on root thickness and nutrient, resulting in the decoupled pattern between them. Specifically, variation in species-level traits related to root thickness (including root diameter, RD and specific root length, SRL) was restricted by common ancestry and little plastic to the changing environments, whereas the large-scale variation in woody root nutrient was mainly controlled by environmental differences, especially soil variables. For community-level traits, mean annual temperature (MAT) mainly influenced the community-level root thickness through the direct effect of changes in plant species composition, while soil P had a positive influence effect on community-level root nitrogen concentration (CWM_RN), reflecting the strong influence of soil fertility on belowground root nutrient. The different environmental constraints and selective pressures acting between root thickness and nutrient traits allows for multiple ecological strategies to adapt to complex environmental conditions. In addition, strong relationships between community-level root traits and environmental variables, due to environmental filters, indicate that in contrast

  16. Volumetric PIV behind mangrove-type root models

    Science.gov (United States)

    Kazemi, Amirkhosro; van de Riet, Keith; Curet, Oscar M.

    2017-11-01

    Mangrove trees form dense networks of prop roots in coastal intertidal zones. The interaction of mangroves with the tidal flow is fundamental in estuaries and shoreline by providing water filtration, protection against erosion and habitat for aquatic animals. In this work, we modeled the mangrove prop roots with a cluster of rigid circular cylinders (patch) to investigate its hydrodynamics. We conducted 2-D PIV and V3V in the near- and far-wake in the recirculating water channel. Two models were considered: (1) a rigid patch, and (2) a flexible patch modeled as rigid cylinders with a flexible hinge. We found that Strouhal number changes with porosity while the patch diameter is constant. Based on the wake signature, we defined an effective diameter length scale. The volumetric flow measurements revealed a regular shedding forming von Kármán vortices for the rigid patch while the flexible patch produced a less uniform wake where vortices were substantially distorted. We compare the wake structure between that 2-D PIV and V3V. This analysis of the hydrodynamics of mangrove-root like models can also be extended to understand other complex flows including bio-inspired coastal infrastructures, damping-wave systems, and energy harvesting devices.

  17. Comparison of citrus rooting evaluation methods using root images in soil profiles and root weight Comparação de métodos de avaliação do enraizamento de citros por meio de imagens em perfil de solo e do peso das raízes

    Directory of Open Access Journals (Sweden)

    CARMEN SILVIA VIEIRA JANEIRO NEVES

    2000-12-01

    Full Text Available A digitized image method was compared with a standard washing technique for measuring citrus roots in the field. Video pictures of roots were taken in a soil profile. The profile area analyzed was defined by iron rings, which were also used to remove the roots to determine their dry weight. The roots presented in the pictures were quantified using SIARCS software developed by Embrapa. The root length and area determined by digital images provided a good estimate of root quantity present in the profile.Com o objetivo de comparar métodos de estudo do sistema radicular em citros, foram tomadas, em vídeo, imagens de raízes situadas em um perfil de solo, e as mesmas raízes foram coletadas e pesadas. As raízes presentes nas imagens foram quantificadas (comprimento e área por meio do programa SIARCS, desenvolvido pela Embrapa. A área do perfil analisada foi delimitada por anéis de ferro, que também foram utilizados para retirar as raízes para a determinação do peso seco. O comprimento e a área de raízes, determinados por imagens digitalizadas, forneceram uma boa estimativa da quantidade de raízes presentes no perfil.

  18. 14CO2 labeling: a reliable technique for rapid measurement of total root exudation capacity and vascular sap flow in crops

    International Nuclear Information System (INIS)

    Singh, Bhupinder; Ahuja, Sumedha; Pandey, Renu; Singhal, R.K.

    2014-01-01

    Ability of roots to release organic compounds in its rhizosphere is known to improve plant available nutrients and reduces heavy metal toxicity by immobilization. It is regarded as an important determinant of micro nutrient deficiency tolerance in plants. Uptake of nutrients and translocation of photoassimilates, on the other hand are governed by the strength of the transpiration stream and sink demand respectively. Measurement of vascular sap flow, thus, is critical for understanding of the translocation efficiency and consequently the sink demand that keeps changing during the crop growth cycle. Measurement of the root exudation capacity and the vascular sap flow is cumbersome and time consuming. Since, the exudates released by the roots and the photosynthates translocated between the source and the sink are essentially carbon compounds, use of labeled carbon as tag could potentially be exploited for a rapid and reliable measurement of exudation and vascular sap flow in crop plants. We report here the experimental results involving 14 C labeling of groundnut, a legume crop, as 14 CO 2 generated by acidification of sodium bicarbonate. An additional factor of seed gamma irradiation was used to generate variability in the root exudation and the sap flow. The 14 C release by the roots was compared against the 14 C transport in the vascular sap. An experimental hypothesis that a higher 14 C level in the vascular sap would indicate a higher root release of carbon by the roots into the rhizosphere was verified. (author)

  19. Polymorphisms in the AOX2 gene are associated with the rooting ability of olive cuttings.

    Science.gov (United States)

    Hedayati, Vahideh; Mousavi, Amir; Razavi, Khadijeh; Cultrera, Nicolò; Alagna, Fiammetta; Mariotti, Roberto; Hosseini-Mazinani, Mehdi; Baldoni, Luciana

    2015-07-01

    Different rooting ability candidate genes were tested on an olive cross progeny. Our results demonstrated that only the AOX2 gene was strongly induced. OeAOX2 was fully characterised and correlated to phenotypical traits. The formation of adventitious roots is a key step in the vegetative propagation of trees crop species, and this ability is under strict genetic control. While numerous studies have been carried out to identify genes controlling adventitious root formation, only a few loci have been characterised. In this work, candidate genes that were putatively involved in rooting ability were identified in olive (Olea europaea L.) by similarity with orthologs identified in other plant species. The mRNA levels of these genes were analysed by real-time PCR during root induction in high- (HR) and low-rooting (LR) individuals. Interestingly, alternative oxidase 2 (AOX2), which was previously reported to be a functional marker for rooting in olive cuttings, showed a strong induction in HR individuals. From the OeAOX2 full-length gene, alleles and effective polymorphisms were distinguished and analysed in the cross progeny, which were segregated based on rooting. The results revealed a possible correlation between two single nucleotide polymorphisms of OeAOX2 gene and rooting ability.

  20. An anatomical study of normal meniscal roots with isotropic 3D MRI at 3 T

    International Nuclear Information System (INIS)

    Ren Ahong; Zheng Zhuozhao; Shang Yao; Tian Chunyan

    2012-01-01

    Objectives: To clarify the morphological features of normal meniscal roots on magnetic resonance (MR) imaging with an isotropic 3D proton density-weighted (PDW) sequence. Materials: 3D PDW MR was performed in sixty-two patients at 3 T before knee arthroscopy. MR images of 34 normal medial menisci and 33 intact lateral menisci confirmed by arthroscopy were retrospectively evaluated. MR signals, insertion sites, dimensions and courses of four meniscal roots were recorded. Results: The anterior root of medial meniscus (ARMM) was typically hypointense, while the posterior root of medial meniscus (PRMM) and the anterior root of lateral meniscus (ARLM) were prone to be hyperintense or showing a comblike signal, and the posterior root of lateral meniscus (PRLM) was usually hypointense or comblike on PDW MR images. ARMM and PRLM had more complex and diverse insertion patterns than ARLM and PRMM. There were significant statistical differences of the lengths, widths, heights and course angles among four meniscal roots (all P < 0.001). Conclusions: The signal intensity of each meniscal root can be hypointense, hyperintense, or comblike on 3D PDW MR images. ARMM and PRLM have more complex and diverse insertion patterns than ARLM and PRMM. The dimensions and courses of four meniscal roots all differ.

  1. Identifying the rooted species tree from the distribution of unrooted gene trees under the coalescent.

    Science.gov (United States)

    Allman, Elizabeth S; Degnan, James H; Rhodes, John A

    2011-06-01

    Gene trees are evolutionary trees representing the ancestry of genes sampled from multiple populations. Species trees represent populations of individuals-each with many genes-splitting into new populations or species. The coalescent process, which models ancestry of gene copies within populations, is often used to model the probability distribution of gene trees given a fixed species tree. This multispecies coalescent model provides a framework for phylogeneticists to infer species trees from gene trees using maximum likelihood or Bayesian approaches. Because the coalescent models a branching process over time, all trees are typically assumed to be rooted in this setting. Often, however, gene trees inferred by traditional phylogenetic methods are unrooted. We investigate probabilities of unrooted gene trees under the multispecies coalescent model. We show that when there are four species with one gene sampled per species, the distribution of unrooted gene tree topologies identifies the unrooted species tree topology and some, but not all, information in the species tree edges (branch lengths). The location of the root on the species tree is not identifiable in this situation. However, for 5 or more species with one gene sampled per species, we show that the distribution of unrooted gene tree topologies identifies the rooted species tree topology and all its internal branch lengths. The length of any pendant branch leading to a leaf of the species tree is also identifiable for any species from which more than one gene is sampled.

  2. Rooting gene trees without outgroups: EP rooting.

    Science.gov (United States)

    Sinsheimer, Janet S; Little, Roderick J A; Lake, James A

    2012-01-01

    Gene sequences are routinely used to determine the topologies of unrooted phylogenetic trees, but many of the most important questions in evolution require knowing both the topologies and the roots of trees. However, general algorithms for calculating rooted trees from gene and genomic sequences in the absence of gene paralogs are few. Using the principles of evolutionary parsimony (EP) (Lake JA. 1987a. A rate-independent technique for analysis of nucleic acid sequences: evolutionary parsimony. Mol Biol Evol. 4:167-181) and its extensions (Cavender, J. 1989. Mechanized derivation of linear invariants. Mol Biol Evol. 6:301-316; Nguyen T, Speed TP. 1992. A derivation of all linear invariants for a nonbalanced transversion model. J Mol Evol. 35:60-76), we explicitly enumerate all linear invariants that solely contain rooting information and derive algorithms for rooting gene trees directly from gene and genomic sequences. These new EP linear rooting invariants allow one to determine rooted trees, even in the complete absence of outgroups and gene paralogs. EP rooting invariants are explicitly derived for three taxon trees, and rules for their extension to four or more taxa are provided. The method is demonstrated using 18S ribosomal DNA to illustrate how the new animal phylogeny (Aguinaldo AMA et al. 1997. Evidence for a clade of nematodes, arthropods, and other moulting animals. Nature 387:489-493; Lake JA. 1990. Origin of the metazoa. Proc Natl Acad Sci USA 87:763-766) may be rooted directly from sequences, even when they are short and paralogs are unavailable. These results are consistent with the current root (Philippe H et al. 2011. Acoelomorph flatworms are deuterostomes related to Xenoturbella. Nature 470:255-260).

  3. Investigation of fungal root colonizers of the invasive plant Vincetoxicum rossicum and co-occurring local native plants in a field and woodland area in Southern Ontario

    Directory of Open Access Journals (Sweden)

    Cindy Bongard

    2013-06-01

    Full Text Available Fungal communities forming associations with plant roots have generally been described as ranging from symbiotic to parasitic. Disruptions to these associations consequently can have significant impacts on native plant communities. We examined how invasion by Vincetoxicum rossicum, a plant native to Europe, can alter both the arbuscular mycorrhizal fungi, as well as the general fungal communities associating with native plant roots in both field and woodland sites in Southern Ontario. In two different sites in the Greater Toronto Area, we took advantage of invasion by V. rossicum and neighbouring uninvaded sites to investigate the fungal communities associating with local plant roots, including goldenrod (Solidago spp., wild red raspberry (Rubus idaeus, Canada anemone (Anemone canadensis, meadow rue (Thalictrum dioicum, and wild ginger (Asarum canadense. Fungi colonizing roots were characterized with terminal restriction fragment length polymorphism (T-RFLP analysis of amplified total fungal (TF and arbuscular mycorrhizal fungal (AMF ribosomal fragments. We saw a significant effect of the presence of this invader on the diversity of TF phylotypes colonizing native plant roots, and a composition shift of both the TF and AMF community in native roots in both sites. In native communities invaded by V. rossicum, a significant increase in richness and colonization density of TF suggests that invaders such as V. rossicum may be able to influence the composition of soil fungi available to natives, possibly via mechanisms such as increased carbon provision or antibiosis attributable to unique root exudates.

  4. RootJS: Node.js Bindings for ROOT 6

    Science.gov (United States)

    Beffart, Theo; Früh, Maximilian; Haas, Christoph; Rajgopal, Sachin; Schwabe, Jonas; Wolff, Christoph; Szuba, Marek

    2017-10-01

    We present rootJS, an interface making it possible to seamlessly integrate ROOT 6 into applications written for Node.js, the JavaScript runtime platform increasingly commonly used to create high-performance Web applications. ROOT features can be called both directly from Node.js code and by JIT-compiling C++ macros. All rootJS methods are invoked asynchronously and support callback functions, allowing non-blocking operation of Node.js applications using them. Last but not least, our bindings have been designed to platform-independent and should therefore work on all systems supporting both ROOT 6 and Node.js. Thanks to rootJS it is now possible to create ROOT-aware Web applications taking full advantage of the high performance and extensive capabilities of Node.js. Examples include platforms for the quality assurance of acquired, reconstructed or simulated data, book-keeping and e-log systems, and even Web browser-based data visualisation and analysis.

  5. [Allelopathy autotoxicity effects of aquatic extracts from rhizospheric soil on rooting and growth of stem cuttings in Pogostemon cablin].

    Science.gov (United States)

    Tang, Kun; Li, Ming; Dong, Shan; Li, Yun-qi; Huang, Jie-wen; Li, Long-ming

    2014-06-01

    To study the allelopathy effects of aquatic extracts from rhizospheric soil on the rooting and growth of stem cutting in Pogostemon cablin, and to reveal its mechanism initially. The changes of rhizogenesis characteristics and physic-biochemical during cutting seedlings were observed when using different concentration of aquatic extracts from rhizospheric soil. Aquatic extracts from rhizospheric soil had significant inhibitory effects on rooting rate, root number, root length, root activity, growth rate of cutting with increasing concentrations of tissue extracts; The chlorophyll content of cutting seedlings were decreased, but content of MDA were increased, and activities of POD, PPO and IAAO in cutting seedlings were affected. Aquatic extracts from rhizospheric soil of Pogostemon cablin have varying degrees of inhibitory effects on the normal rooting and growth of stem cuttings.

  6. Toxic effects of boron on growth and antioxidant system parameters of maize (Zea mays L.) roots.

    Science.gov (United States)

    Esim, Nevzat; Tiryaki, Deniz; Karadagoglu, Omer; Atici, Okkes

    2013-10-01

    The aim of this study was to investigate the possible oxidative stress and the antioxidant response, which were caused on maize by boron (B). For this, 11- and 15-day-old maize seedlings were subjected to 2 or 4 mM B in the form of boric acid (H₃BO₃) for 2 and/or 6 days. At the end of the treatment period, root length, hydrogen peroxide (H₂O₂) content, malondialdehyde (MDA) content and the antioxidant enzymes superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT) were measured. The results revealed that root length of plants, activity of antioxidative enzymes such as SOD, POX and CAT and also H₂O₂ contents and MDA levels were seriously affected by excess B. These results suggested that the oxidative stress occurred due to the toxic effect of B.

  7. Comparative study of 6 rotary nickel-titanium systems and hand instrumentation for root canal preparation in severely curved root canals of extracted teeth.

    Science.gov (United States)

    Celik, Davut; Taşdemir, Tamer; Er, Kürşat

    2013-02-01

    Some improvements have been developed with new generations of nickel-titanium (NiTi) rotary instruments that led to their successful and extensive application in clinical practice. The purpose of this in vitro study was to compare the root canal preparations performed by using GT Series X and Twisted File systems produced by innovative manufacturing process with Revo-S, RaCe, Mtwo, and ProTaper Universal systems manufactured directly from conventional nitinol and with stainless steel K-Flexofile instruments. The mesiobuccal root canals of 140 maxillary first permanent molars that had between 30°-40° curvature angle and 4- to 9-mm curvature radius of the root canal were used. After root canal preparations made by using GT Series X, Twisted File, Revo-S, RaCe, Mtwo, and ProTaper Universal NiTi rotary systems and stainless steel K-Flexofile instruments, transportation occurred in the root canal, and alteration of working length (WL) was assessed by using a modified double-digital radiographic technique. The data were compared by the post hoc Tukey honestly significant difference test. NiTi rotary systems caused less canal transportation and alteration of WL than K-Flexofile instruments (P .05) except 2.5 mm from the WL. At this level ProTaper Universal system caused significant canal transportation (P ProTaper Universal rotary systems manufactured by traditional methods. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  8. Evaluation of bacterial leakage of four root- end filling materials: Gray Pro Root MTA, White Pro Root MTA, Root MTA and Portland Cement (type I

    Directory of Open Access Journals (Sweden)

    Zarabian M.

    2005-07-01

    Full Text Available Background and Aim: Today several materials have been used for root- end filling in endodontic surgery. Optimal properties of Pro Root MTA in in-vitro and in-vivo studies has been proven. On the other hand, based on some studies, Root MTA (Iranian Pro Root MTA and Portland cement are similar to Pro Root MTA in physical and biologic properties. The aim of this study was to evaluate bacterial leakage (amount and mean leakage time of four root- end filling materials. Materials and Methods: In this experimental in-vitro study, seventy six extracted single- rooted human teeth were randomly divided into six groups for root-end filling with gray Pro Root MTA, white Pro Root MTA, Root MTA (Iranian Pro Root MTA, Portland Cement (type I and positive and negative control groups. Root canals were instrumented using the step- back technique. Root- end filling materials were placed in 3mm ultra sonic retro preparations. Samples and microleakage model system were sterilized in autoclave. The apical 3-4 mm of the roots were immersed in phenol red with 3% lactose broth culture medium. The coronal access of each specimen was inoculated every 24h with a suspension of Streptococcus sanguis (ATCC 10556. Culture media were observed every 24h for colour change indicating bacterial contamination for 60 days. Statistical analysis was performed using log- rank test with P<0.05 as the limit of significance. Results: At the end of study 50%, 56.25%, 56.25% and 50% of specimens filled with Gray Pro Root MTA, White Pro Root MTA. Root MTA and Portland Cement (type I had evidence of leakage respectively. The mean leakage time was 37.19±6.29, 36.44±5.81, 37.69±5.97 and 34.81±6.67 days respectively. Statistical analysis of data showed no significant difference among the leakage (amount and mean leakage time of the four tested root- end filling materials (P=0.9958. Conclusion: Based on the results of this study, there were no significant differences in leakage among the four

  9. Influence of development, postharvest handling, and storage conditions on the carbohydrate components of sweetpotato (Ipomea batatas Lam.) roots.

    Science.gov (United States)

    Nabubuya, Agnes; Namutebi, Agnes; Byaruhanga, Yusuf; Narvhus, Judith; Wicklund, Trude

    2017-11-01

    Changes in total starch and reducing sugar content in five sweetpotato varieties were investigated weekly during root development and following subjection of the roots to different postharvest handling and storage conditions. Freshly harvested (noncured) roots and cured roots (spread under the sun for 4 days at 29-31°C and 63-65% relative humidity [RH]) were separately stored at ambient conditions (23°C-26°C and 70-80% RH) and in a semiunderground pit (19-21°C and 90-95% RH). Changes in pasting properties of flour from sweetpotato roots during storage were analyzed at 14-day intervals. Significant varietal differences ( p  < .05) in total starch, sucrose, glucose, maltose, and fructose concentrations were registered. The total starch and sucrose content of the roots did not change significantly ( p  < .05) during root development (72.4 and 7.4%, respectively), whereas the average concentrations of glucose, maltose, and fructose decreased markedly (0.46-0.18%, 0.55-0.28%, and 0.43-0.21%), respectively. Storage led to decrease in total starch content (73-47.7%) and increase in sucrose and glucose concentrations (8.1-11.2% and 0.22-1.57%, respectively). Storage also resulted in reduction in sweetpotato flour pasting viscosities. Curing resulted in increased sucrose and glucose concentrations (9.1-11.2% and 0.45-0.85%, respectively) and marked reduction ( p  < .05) in total starch content (72.9-47.6%). This resulted in low pasting viscosities compared to flour from storage of uncured roots. These findings show that significant changes occur in the carbohydrate components of sweetpotato roots during storage compared to development and present an opportunity for diverse utilization of flours from sweetpotato roots in the food industry.

  10. Sugarcane root length density and distribution from root intersection counting on a trench-profile Densidade de comprimento e distribuição de raízes de cana-de-açúcar a partir da contagem de intersecção de raízes na parede do perfil

    Directory of Open Access Journals (Sweden)

    Mateus Carvalho Basilio de Azevedo

    2011-02-01

    Full Text Available Root length density (RLD is a critical feature in determining crops potential to uptake water and nutrients, but it is difficult to be measured. No standard method is currently available for assessing RLD in the soil. In this study, an in situ method used for other crops for studying root length density and distribution was tested for sugarcane (Saccharum spp.. This method involved root intersection counting (RIC on a Rhodic Eutrudox profile using grids with 0.05 x 0.05 m and modeling RLD from RIC. The results were compared to a conventional soil core-sampled method (COR (volume 0.00043 m³. At four dates of the cropping season in three tillage treatments (plowing soil, minimum tillage and direct planting, with eight soil depths divided in 0.1 m soil layer (between 0-0.6 and 1.6-1.8 m and three horizontal distances from the row (0-0.23, 0.23-0.46 and 0.46-0.69 m, COR and RIC methods presented similar RLD results. A positive relationship between COR and RIC was found (R² = 0.76. The RLD profiles considering the average of the three row distances per depth obtained using COR and RIC (mean of four dates and 12 replications were close and did not differ at each depth of 0.1 m within a total depth of 0.6 m. Total RLD between 0 and 0.6 m was 7.300 and 7.100 m m-2 for COR and RIC respectively. For time consumption, the RIC method was tenfold less time-consuming than COR and RIC can be carried out in the field with no need to remove soil samples. The RLD distribution in depth and row distance (2-D variability by RIC can be assessed in relation to the soil properties in the same soil profiles. The RIC method was suitable for studying these 2-D (depth and row distance in the soil profile relationships between soil, tillage and root distribution in the field.A densidade de comprimento de raízes (DCR é uma característica importante para determinar o potencial de absorção de água e nutrientes das plantas, mas é difícil de ser medida. Nenhum m

  11. Hydrologic control on the root growth of Salix cuttings at the laboratory scale

    Science.gov (United States)

    Bau', Valentina; Calliari, Baptiste; Perona, Paolo

    2017-04-01

    Riparian plant roots contribute to the ecosystem functioning and, to a certain extent, also directly affect fluvial morphodynamics, e.g. by influencing sediment transport via mechanical stabilization and trapping. There is much both scientific and engineering interest in understanding the complex interactions among riparian vegetation and river processes. For example, to investigate plant resilience to uprooting by flow, one should quantify the probability that riparian plants may be uprooted during specific flooding event. Laboratory flume experiments are of some help to this regard, but are often limited to use grass (e.g., Avena and Medicago sativa) as vegetation replicate with a number of limitations due to fundamental scaling problems. Hence, the use of small-scale real plants grown undisturbed in the actual sediment and within a reasonable time frame would be particularly helpful to obtain more realistic flume experiments. The aim of this work is to develop and tune an experimental technique to control the growth of the root vertical density distribution of small-scale Salix cuttings of different sizes and lengths. This is obtained by controlling the position of the saturated water table in the sedimentary bed according to the sediment size distribution and the cutting length. Measurements in the rhizosphere are performed by scanning and analysing the whole below-ground biomass by means of the root analysis software WinRhizo, from which root morphology statistics and the empirical vertical density distribution are obtained. The model of Tron et al. (2015) for the vertical density distribution of the below-ground biomass is used to show that experimental conditions that allow to develop the desired root density distribution can be fairly well predicted. This augments enormously the flexibility and the applicability of the proposed methodology in view of using such plants for novel flow erosion experiments. Tron, S., Perona, P., Gorla, L., Schwarz, M., Laio, F

  12. Revisiting the iron pools in cucumber roots: identification and localization.

    Science.gov (United States)

    Kovács, Krisztina; Pechoušek, Jiří; Machala, Libor; Zbořil, Radek; Klencsár, Zoltán; Solti, Ádám; Tóth, Brigitta; Müller, Brigitta; Pham, Hong Diep; Kristóf, Zoltán; Fodor, Ferenc

    2016-07-01

    Fe deficiency responses in Strategy I causes a shift from the formation of partially removable hydrous ferric oxide on the root surface to the accumulation of Fe-citrate in the xylem. Iron may accumulate in various chemical forms during its uptake and assimilation in roots. The permanent and transient Fe microenvironments formed during these processes in cucumber which takes up Fe in a reduction based process (Strategy I) have been investigated. The identification of Fe microenvironments was carried out with (57)Fe Mössbauer spectroscopy and immunoblotting, whereas reductive washing and high-resolution microscopy was applied for the localization. In plants supplied with (57)Fe(III)-citrate, a transient presence of Fe-carboxylates in removable forms and the accumulation of partly removable, amorphous hydrous ferric oxide/hydroxyde have been identified in the apoplast and on the root surface, respectively. The latter may at least partly be the consequence of bacterial activity at the root surface. Ferritin accumulation did not occur at optimal Fe supply. Under Fe deficiency, highly soluble ferrous hexaaqua complex is transiently formed along with the accumulation of Fe-carboxylates, likely Fe-citrate. As (57)Fe-citrate is non-removable from the root samples of Fe deficient plants, the major site of accumulation is suggested to be the root xylem. Reductive washing results in another ferrous microenvironment remaining in the root apoplast, the Fe(II)-bipyridyl complex, which accounts for ~30 % of the total Fe content of the root samples treated for 10 min and rinsed with CaSO4 solution. When (57)Fe(III)-EDTA or (57)Fe(III)-EDDHA was applied as Fe-source higher soluble ferrous Fe accumulation was accompanied by a lower total Fe content, confirming that chelates are more efficient in maintaining soluble Fe in the medium while less stable natural complexes as Fe-citrate may perform better in Fe accumulation.

  13. The Dietary Approaches to Stop Hypertension Diet and New and Recurrent Root Caries Events in Men.

    Science.gov (United States)

    Kaye, Elizabeth K; Heaton, Brenda; Sohn, Woosung; Rich, Sharron E; Spiro, Avron; Garcia, Raul I

    2015-09-01

    To examine the effect of overall dietary quality on number of teeth with new or recurrent root caries events during follow-up (root caries increment). Prospective study with dental examinations approximately every 3 years over 20 years. Veterans Affairs Dental Longitudinal Study in greater Boston, Massachusetts, area. Men aged 47 to 90 (N = 533). A single calibrated examiner assessed root caries and restorations, calculus, probing pocket depth, and attachment loss on each tooth at each examination. The adjusted root caries increment (root-ADJCI) was computed from new and recurrent root caries events on teeth with recession of 2 mm or more. Dietary information was obtained from food frequency questionnaires. An adherence score was computed by comparing consumption frequency of 10 food groups (fruits, vegetables, total dairy, low-fat dairy, meat, total grains, high-fiber grains, legumes, fats, sweets) from the Dietary Approaches to Stop Hypertension (DASH) diet guidelines. Mean root-ADJCIs were compared according to DASH adherence score quartile using generalized linear negative binomial regression models, controlling for age, number of teeth at risk of root caries, time at risk of root caries, calculus, presence of removable denture, history of dental prophylaxis, body mass index, and smoking status. Men with DASH adherence scores in the highest quartile had a 30% lower mean root-ADJCI (1.86 teeth) than those in the lowest quartile (2.68 teeth) (P = .03). Root-ADJCI was lower with greater adherence to recommendations for vegetables and total grains and greater with greater sugar-sweetened carbonated beverage consumption. Root caries incidence rate did not vary significantly between quartiles. A higher-quality diet may reduce root caries risk in older men. © 2015, Copyright the Authors Journal compilation © 2015, The American Geriatrics Society.

  14. Effects of IAA and IBA on the in vitro rooting of stem cuttings of Sechium edule (Jacq. Sw

    Directory of Open Access Journals (Sweden)

    José García García

    2015-01-01

    Full Text Available This investigation was carried out with the objective of evaluating the response of shoots of chayote [S. edule (Jacq. Sw.] to the application of indole-3-butyric acid (IBA and indole-3-acetic acid (IAA on the in vitro rooting phase. The effect of three culture media, modified from the proposed of Murashige and Skoog (MS was studied: 1- 65% MS salt base, 2- 65% MS salt base + 0.05 mg l-1 of indolebutyric acid (AIB and 3- 65% MS salt base + 3.0 mg l-1-3-indole acetic acid (IAA. The variables evaluated were: number of roots, length and number of shoots per in vitro seedling. The best result were obtained when using 65% MS salt base with 3.0 mg l-1 of IAA. Significant differences (P<0.05 among treatments containing growth regulators was obtained for the variables number of roots and length of in vitro plantlets. In the UNA-730 accession root induction was obtained in a 65% MS salt base culture medium without growth regulators; however, when IAA and IBA was added the induction was 100%. The differences identified in this work with regards to the root induction were probably the combined result of genotype and specific culture conditions. Key words: auxins, chayote, growth regulators, in vitro culture

  15. [Effects of neighbor competition on growth, fine root morphology and distribution of Schima superba and Cunninghamia lanceolata in different nutrient environments].

    Science.gov (United States)

    Yao, Jia Bao; Chu, Xiu Li; Zhou, Zhi Chun; Tong, Jian She; Wang, Hui; Yu, Jia Zhong

    2017-05-18

    Taking Schima superba and Cunninghamia lanceolata as test materials, a pot experiment was conducted to simulate the heterogeneous and homogeneous forest soil nutrient environments, and design three planting modes including single plant, two-strain pure plant and two-strain mixed ones to reason the promotion in mixed S. superba and C. lanceolata plantation and the competitive advantage of S. superba. Results showed that compared with the homogeneous nutrient environment, both S. superba and C. lanceolata had the higher seedling height and dry matter accumulation, when mixed in the heterogeneous nutrient environment, S. superba displayed the obviously competitive advantage, which related to its root plasticity. The fine root of S. superba mixed in each diameter class showed a lot of hyperplasia, and the root total length, surface area and volume of which were 80%-180% higher than that of C. lanceolata. S. superba took the advantage of the compensatory growth strategy of vertical direction in fine roots, namely, they still multiplied to gain greater competitive advantage in low nutrient patches, besides occupying eutrophic surface. The different soil colonization and niche differentiation in fine root of S. superba and C. lanceolata alleviated the strong competition for nutrients of the roots of the two species, and improved the mixed-plantation production. Pure plantation of S. superba harvested the lower yield, which due to the root self-recognition inhibited the growth of root system. Fine roots staggered and evenly distributed on the space might be a reason for stable structure of pure S. superba plantation. So, it was recommended that block surface layer soil preparation and fertilization are used to improve the soil nutrient distribution, and the mixed plantation is constructed to promote the growth of S. superba and C. lanceolata, at the same time, the stand density is regulated to promote tree growth for the pure artificial S. superba plantation which had

  16. Technical Quality of Root Canal Treatment Performed by Undergraduate Clinical Students of Isfahan Dental School.

    Science.gov (United States)

    Saatchi, Masoud; Mohammadi, Golshan; Vali Sichani, Armita; Moshkforoush, Saba

    2018-01-01

    The aim of the present study was to evaluate the radiographic quality of RCTs performed by undergraduate clinical students of Dental School of Isfahan University of Medical Sciences. In this cross sectional study, records and periapical radiographs of 1200 root filled teeth were randomly selected from the records of patients who had received RCTs in Dental School of Isfahan University of Medical Sciences from 2013 to 2015. After excluding 416 records, the final sample consisted of 784 root-treated teeth (1674 root canals). Two variables including the length and the density of the root fillings were examined. Moreover, the presence of ledge, foramen perforation, root perforation and fractured instruments were also evaluated as procedural errors. Descriptive statistics were used for expressing the frequencies of criteria and chi square test was used for comparing tooth types, tooth locations and academic level of students ( P students was not satisfactory and incidence of procedural errors was considerable.

  17. Surgical management of aortic root disease in Marfan syndrome and other congenital disorders associated with aortic root aneurysms.

    Science.gov (United States)

    Treasure, Tom; Takkenberg, J J M; Pepper, John

    2014-10-01

    Elective root replacement in Marfan syndrome has improved life expectancy in affected patients. Three forms of surgery are now available: total root replacement (TRR) with a valved conduit, valve sparing root replacement (VSRR) and personalised external aortic root support (PEARS) with a macroporous mesh sleeve. TRR can be performed irrespective of aortic dimensions and a mechanical replacement valve is a secure and near certain means of correcting aortic valve regurgitation but has thromboembolic and bleeding risks. VSRR offers freedom from anticoagulation and attendant risks of bleeding but reoperation for aortic regurgitation runs at 1.3% per annum. A prospective multi-institutional study has found this to be an underestimate of the true rate of valve-related adverse events. PEARS conserves the aortic root anatomy and optimises the chance of maintaining valve function but average follow-up is under 5 years and so the long-term results are yet to be determined. Patients are on average in their 30s and so the cumulative lifetime need for reoperation, and of any valve-related complications, are consequently substantial. With lowering surgical risk of prophylactic root replacement, the threshold for intervention has reduced progressively over 30 years to 4.5 cm and so an increasing number of patients who are not destined to have a dissection are now having root replacement. In evaluation of these three forms of surgery, the number needed to treat to prevent dissection and the balance of net benefit and harm in future patients must be considered.

  18. Pulpal status of human primary teeth with physiological root resorption.

    Science.gov (United States)

    Monteiro, Joana; Day, Peter; Duggal, Monty; Morgan, Claire; Rodd, Helen

    2009-01-01

    The overall aim of this study was to determine whether any changes occur in the pulpal structure of human primary teeth in association with physiological root resorption. The experimental material comprised 64 sound primary molars, obtained from children requiring routine dental extractions under general anaesthesia. Pulp sections were processed for indirect immunofluorescence using combinations of: (i) protein gene product 9.5 (a general neuronal marker); (ii) leucocyte common antigen CD45 (a general immune cell marker); and (iii) Ulex europaeus I lectin (a marker of vascular endothelium). Image analysis was then used to determine the percentage area of staining for each label within both the pulp horn and mid-coronal region. Following measurement of the greatest degree of root resorption in each sample, teeth were subdivided into three groups: those with physiological resorption involving less than one-third, one-third to two-thirds, and more than two-thirds of their root length. Wide variation was evident between different tooth samples with some resorbed teeth showing marked changes in pulpal histology. Decreased innervation density, increased immune cell accumulation, and increased vascularity were evident in some teeth with advanced root resorption. Analysis of pooled data, however, did not reveal any significant differences in mean percentage area of staining for any of these variables according to the three root resorption subgroups (P > 0.05, analysis of variance on transformed data). This investigation has revealed some changes in pulpal status of human primary teeth with physiological root resorption. These were not, however, as profound as one may have anticipated. It is therefore speculated that teeth could retain the potential for sensation, healing, and repair until advanced stages of root resorption.

  19. Analysis of the relationship between rusty root incidences and soil properties in Panax ginseng

    Science.gov (United States)

    Wang, Q. X.; Xu, C. L.; Sun, H.; Ma, L.; Li, L.; Zhang, D. D.; Zhang, Y. Y.

    2016-08-01

    Rusty root is a serious problem in ginseng cultivation that limits the production and quality of ginseng worldwide. The Changbai Mountains are the most famous area for ginseng cultivation in China. To clarify the relationship between rusty root and soil characteristics, physico-chemical properties and enzymatic activities of soil collected from five different fields in the Changbai Mountains were analyzed and a controlled experiment carried out by increasing the concentration of Fe (II). Soil bulk density, moisture, total iron (Fe) and total manganese (Mn) concentrations and polyphenol oxidase (PPO) activity were significantly higher in rusty root than healthy root groups (two-sample test, Ptest showed that there was a significant positive correlation between rusty root index and pH, N, Fe, Mn, Al, Zn and Ca of soil samples collected from fields (P<0.05 or P<0.01), and a significant positive correlation also occurred between rusty root index and Fe (II) added to soil in Fe (II) inducing rusty root (P<0.01). Physiological factors may be very important roles giving rise to ginseng rusty root. Fe (III) reduction and Fe (II) oxidation could be important in increasing the incidence of rusty root. Soil moisture and bulk density of non-rhizosphere soil not attached to the root surface, and pH, N and PPO content of rhizosphere soils attached to the root surface were heavily involved in the reduction, oxidation and sequestration of metal ions.

  20. A New Maximum Length Record of the Bluefish (Pomatomus saltatrix Linnaeus, 1766) for Turkey Seas

    OpenAIRE

    Cengiz, Özgür

    2014-01-01

    One specimen of the bluefish (Pomatomus saltatrix Linnaeus, 1766) with 76.5 cm in total length and 4800.0 g in total weight was photographed in the Çanakkale Fish Market. The given length is second maximum length record of the bluefish for Turkish waters