WorldWideScience

Sample records for adventitious rooting process1

  1. Adventitious Roots and Secondary Metabolism

    Institute of Scientific and Technical Information of China (English)

    Hosakatte Niranjana Murthy; Eun Joo Hahn; Kee Yoeup Paek

    2008-01-01

    Plants are a rich source of valuable secondary metabolites and in the recent years plant cell, tissue and organ cultures have been developed as an important alternative sources for the production of these compounds. Adventitious roots have been successfully induced in many plant species and cultured for the production of high value secondary metabolites of pharmaceutical, nutraceutical and industrial importance. Adoption of elicitation methods have shown improved synthesis of secondary metabolites in adventitious root cultures. Development of large-scale culture methods using bioreactors has opened up feasibilities of production of secondary metabolites at the industrial levels. In the present review we summarize the progress made in recent past in the area of adventitious root cultures for the production of secondary metabolites.

  2. Inhibition of strigolactones promotes adventitious root formation

    OpenAIRE

    Rasmussen, Amanda; Beveridge, Christine A.; Geelen, Danny

    2012-01-01

    Roots that form from non-root tissues (adventitious roots) are crucial for cutting propagation in the forestry and horticulture industries. Strigolactone has been demonstrated to be an important regulator of these roots in both Arabidopsis and pea using strigolactone deficient mutants and exogenous hormone applications. Strigolactones are produced from a carotenoid precursor which can be blocked using the widely available but broad terpenoid biosynthesis blocker, fluridone. We demonstrate her...

  3. Strigolactones suppress adventitious rooting in Arabidopsis and pea.

    Science.gov (United States)

    Rasmussen, Amanda; Mason, Michael Glenn; De Cuyper, Carolien; Brewer, Philip B; Herold, Silvia; Agusti, Javier; Geelen, Danny; Greb, Thomas; Goormachtig, Sofie; Beeckman, Tom; Beveridge, Christine Anne

    2012-04-01

    Adventitious root formation is essential for the propagation of many commercially important plant species and involves the formation of roots from nonroot tissues such as stems or leaves. Here, we demonstrate that the plant hormone strigolactone suppresses adventitious root formation in Arabidopsis (Arabidopsis thaliana) and pea (Pisum sativum). Strigolactone-deficient and response mutants of both species have enhanced adventitious rooting. CYCLIN B1 expression, an early marker for the initiation of adventitious root primordia in Arabidopsis, is enhanced in more axillary growth2 (max2), a strigolactone response mutant, suggesting that strigolactones restrain the number of adventitious roots by inhibiting the very first formative divisions of the founder cells. Strigolactones and cytokinins appear to act independently to suppress adventitious rooting, as cytokinin mutants are strigolactone responsive and strigolactone mutants are cytokinin responsive. In contrast, the interaction between the strigolactone and auxin signaling pathways in regulating adventitious rooting appears to be more complex. Strigolactone can at least partially revert the stimulatory effect of auxin on adventitious rooting, and auxin can further increase the number of adventitious roots in max mutants. We present a model depicting the interaction of strigolactones, cytokinins, and auxin in regulating adventitious root formation. PMID:22323776

  4. Effect of sucrose on adventitious root regeneration in apple

    NARCIS (Netherlands)

    Calamar, A.; Klerk, de G.J.M.

    2002-01-01

    We have examined the effect of sucrose on adventitious root formation in apple microcuttings and in 1-mm stem slices cut from apple microcuttings. The sucrose concentration influenced the number of adventitious roots, but at a broad range of sucrose concentrations (1¿9%) the effect was small. In add

  5. Auxin Control in the Formation of Adventitious Roots

    OpenAIRE

    Tiberia I. POP; Pamfil, Doru; Bellini, Catherine

    2011-01-01

    Adventitious rooting is a complex process and a key step in the vegetative propagation of economically important woody, horticultural and agricultural species, playing an important role in the successful production of elite clones. The formation of adventitious roots is a quantitative genetic trait regulated by both environmental and endogenous factors. Among phytohormones, auxin plays an essential role in regulating roots development and it has been shown to be intimately involved in the pro...

  6. Hypocotyl adventitious root organogenesis differs from lateral root development

    Directory of Open Access Journals (Sweden)

    Inge eVerstraeten

    2014-09-01

    Full Text Available Wound-induced adventitious root (AR formation is a requirement for plant survival upon root damage inflicted by pathogen attack, but also during the regeneration of plant stem cuttings for clonal propagation of elite plant varieties. Yet, adventitious rooting also takes place without wounding. This happens for example in etiolated Arabidopsis thaliana hypocotyls, in which AR initiate upon de-etiolation or in tomato seedlings, in which AR initiate upon flooding or high water availability. In the hypocotyl AR originate from a cell layer reminiscent to the pericycle in the primary root (PR and the initiated AR share histological and developmental characteristics with lateral roots (LR. In contrast to the PR however, the hypocotyl is a determinate structure with an established final number of cells. This points to differences between the induction of hypocotyl AR and LR on the PR, as the latter grows indeterminately. The induction of AR on the hypocotyl takes place in environmental conditions that differ from those that control LR formation. Hence, AR formation depends on differentially regulated gene products. Similarly to AR induction in stem cuttings, the capacity to induce hypocotyl AR is genotype-dependent and the plant growth regulator auxin is a key regulator controlling the rooting response. The hormones cytokinins, ethylene, jasmonic acid and strigolactones in general reduce the root-inducing capacity. The involvement of this many regulators indicates that a tight control and fine-tuning of the initiation and emergence of AR exists. Recently, several genetic factors, specific to hypocotyl adventitious rooting in Arabidopsis thaliana, have been uncovered. These factors reveal a dedicated signaling network that drives AR formation in the Arabidopsis hypocotyl. Here we provide an overview of the environmental and genetic factors controlling hypocotyl-born AR and we summarize how AR formation and the regulating factors of this organogenesis are

  7. Auxin Control in the Formation of Adventitious Roots

    Directory of Open Access Journals (Sweden)

    Tiberia I. POP

    2011-05-01

    Full Text Available Adventitious rooting is a complex process and a key step in the vegetative propagation of economically important woody, horticultural and agricultural species, playing an important role in the successful production of elite clones. The formation of adventitious roots is a quantitative genetic trait regulated by both environmental and endogenous factors. Among phytohormones, auxin plays an essential role in regulating roots development and it has been shown to be intimately involved in the process of adventitious rooting. Great progress has been made in elucidating the auxin-induced genes and auxin signaling pathway, especially in auxin response Aux/IAA and Auxin Response Factor gene families. Although some important aspects of adventitious and lateral rooting signaling have been revealed, the intricate signaling network remains poorly understood. This review summarizes some of the current knowledge on the physiological aspects of adventitious root formation and highlights the recent progress made in the identification of putative molecular players involved in the control of adventitious rooting. Despite much has been discovered regarding the effects and regulation of auxins on plant growth since the Darwin experiments, there is much that remains unknown.

  8. Mineral nutrition and adventitious rooting in microcuttings of Eucalyptus globulus.

    Science.gov (United States)

    Schwambach, Joséli; Fadanelli, Cristina; Fett-Neto, Arthur G

    2005-04-01

    We characterized the adventitious rooting response of Eucalyptus globulus Labill. to various concentrations of calcium, nitrogen, phosphorus, iron, manganese, zinc, boron and copper. The parameters analyzed were percent rooting, root number, root length and mean rooting time. Root number and root length were significantly affected by mineral nutrition, whereas mean rooting time and rooting percentage seemed to be closely related to auxin availability. Root number was affected by calcium, nitrogen source and zinc, whereas root length was influenced by concentrations of phosphorus, iron and manganese, and by nitrogen source. Based on these results, we evaluated various combinations of several concentrations of these minerals in each rooting phase. Cuttings that were rooted in an optimized mineral nutrient medium and acclimatized to ex-vitro conditions for two months showed significantly higher survival after transplanting and drought stress than cuttings rooted in basal medium and treated in the same way.

  9. Improvement of adventitious root formation in flax using hydrogen peroxide.

    Science.gov (United States)

    Takáč, Tomáš; Obert, Bohuš; Rolčík, Jakub; Šamaj, Jozef

    2016-09-25

    Flax (Linum usitatissimum L.) is an important crop for the production of oil and fiber. In vitro manipulations of flax are used for genetic improvement and breeding while improvements in adventitious root formation are important for biotechnological programs focused on regeneration and vegetative propagation of genetically valuable plant material. Additionally, flax hypocotyl segments possess outstanding morphogenetic capacity, thus providing a useful model for the investigation of flax developmental processes. Here, we investigated the crosstalk between hydrogen peroxide and auxin with respect to reprogramming flax hypocotyl cells for root morphogenetic development. Exogenous auxin induced the robust formation of adventitious roots from flax hypocotyl segments while the addition of hydrogen peroxide further enhanced this process. The levels of endogenous auxin (indole-3-acetic acid; IAA) were positively correlated with increased root formation in response to exogenous auxin (1-Naphthaleneacetic acid; NAA). Histochemical staining of the hypocotyl segments revealed that hydrogen peroxide and peroxidase, but not superoxide, were positively correlated with root formation. Measurements of antioxidant enzyme activities showed that endogenous levels of hydrogen peroxide were controlled by peroxidases during root formation from hypocotyl segments. In conclusion, hydrogen peroxide positively affected flax adventitious root formation by regulating the endogenous auxin levels. Consequently, this agent can be applied to increase flax regeneration capacity for biotechnological purposes such as improved plant rooting. PMID:26921706

  10. Transcriptome profiling and comparative analysis of Panax ginseng adventitious roots

    OpenAIRE

    Jayakodi, Murukarthick; Lee, Sang-Choon; Park, Hyun-Seung; Jang, Woojong; Lee, Yun Sun; Choi, Beom-Soon; Nah, Gyoung Ju; Kim, Do-Soon; Natesan, Senthil; Sun, Chao; Yang, Tae-Jin

    2014-01-01

    Background Panax ginseng Meyer is a traditional medicinal plant famous for its strong therapeutic effects and serves as an important herbal medicine. To understand and manipulate genes involved in secondary metabolic pathways including ginsenosides, transcriptome profiling of P. ginseng is essential. Methods RNA-seq analysis of adventitious roots of two P. ginseng cultivars, Chunpoong (CP) and Cheongsun (CS), was performed using the Illumina HiSeq platform. After transcripts were assembled, e...

  11. Adventitious roots, leaf abscission and nutrient status of flooded Gmelina and Tectona seedlings.

    Science.gov (United States)

    Osundina, M A; Osonubi, O

    1989-12-01

    When flooded, seedlings of Gmelina arborea Roxb. produced more adventitious roots, had lower foliar Mn concentrations and lost fewer leaves than seedlings of Tectona grandis L.f. Severing the adventitious roots produced by flooded Gmelina seedlings increased leaf Mn concentration and leaf abscission and reduced whole-plant dry matter production. Flooded Gmelina cuttings, which do not produce adventitious roots, abscised few leaves until foliar concentrations of Mn and Fe had risen substantially above those of unflooded cuttings, at which time most leaves were shed. The results indicate that the development of adventitious roots in flooded seedlings of Gmelina suppressed uptake of Mn thereby minimizing leaf abscission. PMID:14972970

  12. Expressed sequence tag analysis of functional genes associated with adventitious rooting in Liriodendron hybrids.

    Science.gov (United States)

    Zhong, Y D; Sun, X Y; Liu, E Y; Li, Y Q; Gao, Z; Yu, F X

    2016-06-24

    Liriodendron hybrids (Liriodendron chinense x L. tulipifera) are important landscaping and afforestation hardwood trees. To date, little genomic research on adventitious rooting has been reported in these hybrids, as well as in the genus Liriodendron. In the present study, we used adventitious roots to construct the first cDNA library for Liriodendron hybrids. A total of 5176 expressed sequence tags (ESTs) were generated and clustered into 2921 unigenes. Among these unigenes, 2547 had significant homology to the non-redundant protein database representing a wide variety of putative functions. Homologs of these genes regulated many aspects of adventitious rooting, including those for auxin signal transduction and root hair development. Results of quantitative real-time polymerase chain reaction showed that AUX1, IRE, and FB1 were highly expressed in adventitious roots and the expression of AUX1, ARF1, NAC1, RHD1, and IRE increased during the development of adventitious roots. Additionally, 181 simple sequence repeats were identified from 166 ESTs and more than 91.16% of these were dinucleotide and trinucleotide repeats. To the best of our knowledge, the present study reports the identification of the genes associated with adventitious rooting in the genus Liriodendron for the first time and provides a valuable resource for future genomic studies. Expression analysis of selected genes could allow us to identify regulatory genes that may be essential for adventitious rooting.

  13. Role of adventitious roots in water relations of tamarack (Larix laricina seedlings exposed to flooding

    Directory of Open Access Journals (Sweden)

    Calvo-Polanco Mónica

    2012-06-01

    Full Text Available Abstract Background Flooding reduces supply of oxygen to the roots affecting plant water uptake. Some flooding-tolerant tree species including tamarack (Larix laricina (Du Roi K. Koch produce adventitious roots in response to flooding. These roots were reported to have higher hydraulic conductivity under flooding conditions compared with non-adventitious roots. In the present study, we examined structural and functional modifications in adventitious roots of tamarack seedlings to explain their flooding tolerance. Results Seedlings were subjected to the flooding treatment for six months, which resulted in an almost complete disintegration of the existing root system and its replacement with adventitious roots. We compared gas exchange parameters and water relations of flooded plants with the plants growing in well-drained soil and examined the root structures and root water transport properties. Although flooded seedlings had lower needle chlorophyll concentrations, their stomatal conductance, net photosynthesis rates and shoot water potentials were similar to non-flooded plants, indicative of flooding tolerance. Flooded adventitious roots had higher activation energy and a higher ratio of apoplastic to cell-to-cell water flow compared with non-flooded control roots as determined with the 1-hydroxypirene 3,6,8-trisulfonic acid apoplastic tracer dye. The adventitious roots in flooded plants also exhibited retarded xylem and endodermal development and accumulated numerous starch grains in the cortex. Microscopic examination of root sections treated with the PIP1 and PIP2 antibodies revealed high immunoreactivity in the cortex of non-flooded roots, as compared with flooded roots. Conclusions Structural modifications of adventitious roots suggest increased contribution of apoplastic bypass to water flow. The reduced dependence of roots on the hypoxia-sensitive aquaporin-mediated water transport is likely among the main mechanisms allowing tamarack

  14. Aquatic adventitious roots of the wetland plant Meionectes brownii can photosynthesize

    DEFF Research Database (Denmark)

    Rich, Sarah Meghan; Ludwig, Martha; Pedersen, Ole;

    2011-01-01

    • Many wetland plants produce aquatic adventitious roots from submerged stems. Aquatic roots can form chloroplasts, potentially producing endogenous carbon and oxygen. Here, aquatic root photosynthesis was evaluated in the wetland plant Meionectes brownii, which grows extensive stem-borne aquatic...... adventitious roots contain a complete photosynthetic pathway. Underwater photosynthetic rates are similar to those of stems, with a maximum net photosynthetic rate (P(max)) of 0.38 µmol O(2) m(-2) s(-1); however, this is c. 30-fold lower than that of aquatic-adapted leaves. Under saturating light with 300 mmol...

  15. Low temperature, IBA concentrations and optimal time for adventitious rooting of Eucalyptus benthamii mini-cuttings

    Institute of Scientific and Technical Information of China (English)

    Gilvano Ebling Brondani; Francisco José Benedini Baccarin; Heron Wilhelmus de Wit Ondas; José Luiz Stape; Antonio Natal Gon(c)alves; Marcilio de Almeida

    2012-01-01

    Eucalyptus benthamii is a forest species of economic interest that has difficulty with seed production and also is considered to have difficulty with adventitious rooting using propagation techniques,such as cutting or mini-cutting.We aimed to assess the adventitious rooting percentage under different storage times in low temperatures and at various IBA (indole-3-butyric acid) concentrations to determine the optimal time of permanence for rooting Eucalyptus benthamii minicuttings in a greenhouse.Shoots collected from mini-stumps cultivated in a semi-hydroponic system were used to obtain the mini-cuttings.For the first experiment,the mini-cuttings were stored at 4℃ for 0 (immediate planting),24,48,72,96 and 120 h.The second experiment evaluated the rooting dynamic to determine the optimal time of permanence for minicuttings in a greenhouse.The basal region of the mini-cutting was treated with various 1BA solutions:0 (free of IBA),1,000,2,000,3,000 and 4,000 mg·L-1.Every seven days (0 (immediate planting),7,14,21 and 28days),destructive sampling of the mini-cuttings was performed to evaluate the histology of the adventitious rooting.Eucalyptus benthamii minicuttings should be rooted immediately after the collection of the shoots.The 2,000 mg·L-1 IBA concentration induced a greater speed and percentage of adventitious rooting,and an interval of 35 to 42 days was indicated for permanence of the mini-cuttings in the greenhouse.Exposure to low temperature induced adventitious root formation with diffuse vascular connections.

  16. Adventitious rooting in cuttings of croton and hibiscus in response to indolbutyric acid and humic acid

    OpenAIRE

    Lílian Estrela Borges Baldotto; Marihus Altoé Baldotto; Raíssa Rezende Soares; Herminia Emilia Prieto Martinez; Vitor Hugo Alvarez Venegas

    2012-01-01

    Adventitious rooting of ornamental plants can be accelerated by the application of growth regulators, such as auxin. Humic acids, organic matter in soil and organic compounds also have a biostimulant effect. This work evaluated the rooting in cuttings of croton (Codianeum variegatum L. Rumph) and hibiscus (Hibiscus rosa-sinensis L) in response to the application of different concentrations of indolbutyric acid (IBA) and humic acid (HA). The experiment was carried out in a greenhouse. Apical s...

  17. Chemical characterization and prebiotic activity of fructo-oligosaccharides from Stevia rebaudiana (Bertoni) roots and in vitro adventitious root cultures.

    Science.gov (United States)

    Sanches Lopes, Sheila Mara; Francisco, Mariane Grigio; Higashi, Bruna; de Almeida, Rafaela Takako Ribeiro; Krausová, Gabriela; Pilau, Eduardo Jorge; Gonçalves, José Eduardo; Gonçalves, Regina Aparecida Correia; Oliveira, Arildo José Braz de

    2016-11-01

    Stevia rebaudiana (Bertoni) is widely studied because of its foliar steviol glycosides. Fructan-type polysaccharides were recently isolated from its roots. Fructans are reserve carbohydrates that have important positive health effects and technological applications in the food industry. The objective of the present study was to isolate and characterize fructo-oligosaccharides (FOSs) from S. rebaudiana roots and in vitro adventitious root cultures and evaluate the potential prebiotic effect of these molecules. The in vitro adventitious root cultures were obtained using a roller bottle system. Chemical analyses (gas chromatography-mass spectrometry, (1)H nuclear magnetic resonance, and off-line electrospray ionization-mass spectrometry) revealed similar chemical properties of FOSs that were obtained from the different sources. The potential prebiotic effects of FOSs that were isolated from S. rebaudiana roots enhanced the growth of both bifidobacteria and lactobacilli, with strains specificity in their fermentation ability. PMID:27516323

  18. The role of strigolactones in photomorphogenesis of pea is limited to adventitious rooting.

    Science.gov (United States)

    Urquhart, Shelley; Foo, Eloise; Reid, James B

    2015-03-01

    The recently discovered group of plant hormones, the strigolactones, have been implicated in regulating photomorphogenesis. We examined this extensively in our strigolactone synthesis and response mutants and could find no evidence to support a major role for strigolactone signaling in classic seedling photomorphogenesis (e.g. elongation and leaf expansion) in pea (Pisum sativum), consistent with two recent independent reports in Arabidopsis. However, we did find a novel effect of strigolactones on adventitious rooting in darkness. Strigolactone-deficient mutants, Psccd8 and Psccd7, produced significantly fewer adventitious roots than comparable wild-type seedlings when grown in the dark, but not when grown in the light. This observation in dark-grown plants did not appear to be due to indirect effects of other factors (e.g. humidity) as the constitutively de-etiolated mutant, lip1, also displayed reduced rooting in the dark. This role for strigolactones did not involve the MAX2 F-Box strigolactone response pathway as Psmax2 f-box mutants did not show a reduction in adventitious rooting in the dark compared with wild-type plants. The auxin-deficient mutant bushy also reduced adventitious rooting in the dark, as did decapitation of wild-type plants. Rooting was restored by the application of indole-3-acetic acid (IAA) to decapitated plants, suggesting a role for auxin in the rooting response. However, auxin measurements showed no accumulation of IAA in the epicotyls of wild-type plants compared with the strigolactone synthesis mutant Psccd8, suggesting that changes in the gross auxin level in the epicotyl are not mediating this response to strigolactone deficiency. PMID:24962787

  19. Gibberellins inhibit adventitious rooting in hybrid aspen and Arabidopsis by affecting auxin transport.

    Science.gov (United States)

    Mauriat, Mélanie; Petterle, Anna; Bellini, Catherine; Moritz, Thomas

    2014-05-01

    Knowledge of processes involved in adventitious rooting is important to improve both fundamental understanding of plant physiology and the propagation of numerous plants. Hybrid aspen (Populus tremula × tremuloïdes) plants overexpressing a key gibberellin (GA) biosynthesis gene (AtGA20ox1) grow rapidly but have poor rooting efficiency, which restricts their clonal propagation. Therefore, we investigated the molecular basis of adventitious rooting in Populus and the model plant Arabidopsis. The production of adventitious roots (ARs) in tree cuttings is initiated from the basal stem region, and involves the interplay of several endogenous and exogenous factors. The roles of several hormones in this process have been characterized, but the effects of GAs have not been fully investigated. Here, we show that a GA treatment negatively affects the numbers of ARs produced by wild-type hybrid aspen cuttings. Furthermore, both hybrid aspen plants and intact Arabidopsis seedlings overexpressing AtGA20ox1, PttGID1.1 or PttGID1.3 genes (with a 35S promoter) produce few ARs, although ARs develop from the basal stem region of hybrid aspen and the hypocotyl of Arabidopsis. In Arabidopsis, auxin and strigolactones are known to affect AR formation. Our data show that the inhibitory effect of GA treatment on adventitious rooting is not mediated by perturbation of the auxin signalling pathway, or of the strigolactone biosynthetic and signalling pathways. Instead, GAs appear to act by perturbing polar auxin transport, in particular auxin efflux in hybrid aspen, and both efflux and influx in Arabidopsis.

  20. Nitric oxide is involved in hemin-induced cucumber adventitious rooting process.

    Science.gov (United States)

    Xuan, Wei; Xu, Sheng; Li, Meiyue; Han, Bin; Zhang, Bo; Zhang, Jing; Lin, Yuting; Huang, Jingjing; Shen, Wenbiao; Cui, Jin

    2012-07-15

    Hemin, a heme oxygenase-1 (HO-1) inducer, was shown to exert numerous beneficial physiological functions in animals. Our previous study suggests that HO-1/carbon monoxide (CO) acts as a novel downstream signal system in the auxin-induced adventitious rooting. The objective of this study was to test whether nitric oxide (NO) is involved in hemin-induced cucumber adventitious rooting. Applications of hemin or CO aqueous solution to auxin-depleted cucumber explant induced up-regulation of cucumber HO-1 transcripts (CsHO1), NO production, and thereafter adventitious root formation, and some above responses were blocked by the combination treatment with two nitric oxide synthase (NOS)-like enzyme inhibitors N(G)-nitro-L-arginine methylester hydrochloride and N(G)-nitro-L-arginine, a HO-1 specific inhibitor zinc protoporphyrin IX, and a specific NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide potassium salt. However, these blocking responses were not observed using tungstate, an inhibitor of nitrate reductase, another NO producing enzyme in plants. Furthermore, the guanylate cyclase inhibitors 1H-(1,2,4)-oxadiazole[4,3-a]quinoxalin-1-one and 6-anilino-5,8-quinolinedione reduced root development induced by hemin, whereas the cell-permeable cyclic guanosine monophosphate (cGMP) derivative 8-Br-cGMP reversed this effect. Together, our results indicated that at least in our experimental conditions, NO might operate downstream of hemin promoting adventitious root formation probably in a cGMP-dependent manner. PMID:22579358

  1. Regulation of phytohormones on root primordium initiation and adventitious root formation in the etiolated shoots of Paeonia suffruticosa 'Yinfen Jinlin'

    Institute of Scientific and Technical Information of China (English)

    Zeng Duan-xiang; Yin Wei-lun; Zhao Xiao-qing; Wang Hua-fang

    2006-01-01

    Tree peony is well known and sought after for its large, colorful flowers. Its propagation is via vegetative methods. Mechnisms of the adventitious rooting and the regulation of rooting processes are the principles and techniques of plant propagation and improvement. Microstmctures and fluctuations of phytohormones in the adventitious rooting were studied with the etiolated softwood shoots of Paeonia suffruticosa 'Yinfen Jinlin'. There are no pre-primordia in the shoots of the cultivar. Adventitious roots are produced in five stages: shoot selection, primordium initiation, primordium growth, conducting tissue differentiation and root protrusion. Primordia initiated in the cortex. The contents of the endogenous hormones, IAA, ABA and GA, were 5.842, 0.873 and 1.043to GA, CTK and ABA clearly increased at the stage of primordium initiation, while they showed low levels at the stages of primordium growth. The ratios were restored at the shoot levels at the stage of root protrusion. IBA provoked primordia initiation in the cortex, the vascular cambium, the pith and even in the callus induced on the base of shoots. IAA levels in the treated shoots increased gradually to its highest level (three times of control) at the stage of conducting tissue differentiation. The ratios of IAA to GA, CTK and ABA clearly decreased at the stage of primordium initiation. The ratio of IAA to ABA is regulated at 10:1.

  2. Carbon monoxide-induced adventitious rooting of hypocotyl cuttings from mung bean seedling

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In this paper, the regulatory role of exogenous carbon monoxide (CO) during the generation and development of adventitious roots in mung bean (Phaseolus radiatus L. cv. Mingguang) hypocotyl cuttings was surveyed. The results indicated that, like nitric oxide (NO), CO donor Hematin induced adventitious rooting in dose- and time-de- pendent manners. These responses were also prov- en by the addition of gaseous CO aqueous solution with different concentrations. Additionally, the above CO-mediated effect was differently reversed when CO scavenger hemoglobin (Hb), CO specific synthetic inhibitor ZnPPIX, the auxin transport inhibitor NPA and nitric oxide synthase (NOS) inhibitor L-NAME were added with Hematin, respectively. Furthermore, after being treated with CO for 36 h, NO fluorescence was significantly enhanced and mainly distributed in the zone of vascular bundles whereas the specific NO scavenger cPTIO significantly inhibited NO fluorescence induced by CO, indicating that CO induces adventitious rooting of hypocotyl cuttings from mung bean seedling probably mediated by NO/NOS pathway.

  3. Large Scale Culture of Ginseng Adventitious Roots for Production of Ginsenosides

    Science.gov (United States)

    Paek, Kee-Yoeup; Murthy, Hosakatte Niranjana; Hahn, Eun-Joo; Zhong, Jian-Jiang

    Ginseng (Panax ginseng C. A. Meyer) is one of the most famous oriental medicinal plants used as crude drugs in Asian countries, and now it is being used worldwide for preventive and therapeutic purposes. Among diverse constituents of ginseng, saponins (ginsenosides) have been found to be major components responsible for their biological and pharmacological actions. On the other hand, difficulties in the supply of pure ginsenosides in quantity prevent the development of ginseng for clinical medicines. Cultivation of ginseng in fields takes a long time, generally 5-7 years, and needs extensive effort regarding quality control since growth is susceptible to many environmental factors including soil, shade, climate, pathogens and pests. To solve the problems, cell and tissue cultures have been widely explored for more rapid and efficient production of ginseng biomass and ginsenosides. Recently, cell and adventitious root cultures of P. ginseng have been established in large scale bioreactors with a view to commercial application. Various physiological and engineering parameters affecting the biomass production and ginsenoside accumulation have been investigated. Advances in adventitious root cultures including factors for process scale-up are reviewed in this chapter. In addition, biosafety analyses of ginseng adventitious roots are also discussed for real application.

  4. Panax ginseng Adventitious Root Suspension Culture: Protocol for Biomass Production and Analysis of Ginsenosides by High Pressure Liquid Chromatography.

    Science.gov (United States)

    Murthy, Hosakatte Niranjana; Paek, Kee Yoeup

    2016-01-01

    Panax ginseng C.A. Meyer (Korean ginseng) is a popular herbal medicine. It has been used in Chinese and Oriental medicines since thousands of years. Ginseng products are generally used as a tonic and an adaptogen to resist the adverse influence of a wide range of physical, chemical and biological factors, and to restore homeostasis. Ginsenosides or ginseng saponins are the principal active ingredients of ginseng. Since ginseng cultivation process is very slow and needs specific environment for field cultivation, cell and tissue cultures are sought as alternatives for the production of ginseng biomass and bioactive compounds. In this chapter, we focus on methods of induction of adventitious roots from ginseng roots, establishment of adventitious root suspension cultures using bioreactors, procedures for processing of adventitious roots, and analysis of ginsenosides by high pressure liquid chromatography. PMID:27108314

  5. Improvement of Growth and Periplocin Yield of Periploca sepium Adventitious Root Cultures by Altering Nitrogen Source Supply

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian; GAO Wen-yuan; WANG Juan; LI Xing-lin; XIAO Pei-gen

    2011-01-01

    Objective To increase the ultimate yield of periplocin in Periploca sepium adventitious root cultures by a two-stage culture based on nitrogen source.Methods Firstly,the effects of nitrogen source(NH-NO-)at different ratios and different total initial nitrogen amounts on the accumulation of biomass and secondary metabolites in adventitious root cultures of P sepium were investigated,and growth and production media for the two-stage culture based on the above results were established.Results The highest biomass and periplocin content were obtained in the culture medium of 15 mmol/L total nitrogen amount with NH-NO(1:2)and 30 mmol/L total nitrogen amount with nitrate as the sole nitrogen source.By adopting a fed-batch cultivation strategy,the dry weight adventitious root,periplocin content and yield were increased by 136%,108%,and 389%,respectively when compared with those of the control,reaching up to 8.13 g/L,157.15 μg/g,and 1277.63 μg/L,respectively.Furthermore,it was found that in the process of two-stage culture,the adventitious roots grew thicker significantly after they were transferred into production medium directly.Conclusion The ultimate yield of periplocin in P.sepium adventitious root cultures could be significantly increased by a two-stage culture based on nitrogen source.

  6. Hydrogen peroxide is a second messenger in the salicylic acid-triggered adventitious rooting process in mung bean seedlings.

    Science.gov (United States)

    Yang, Wei; Zhu, Changhua; Ma, Xiaoling; Li, Guijun; Gan, Lijun; Ng, Denny; Xia, Kai

    2013-01-01

    In plants, salicylic acid (SA) is a signaling molecule that regulates disease resistance responses, such as systemic acquired resistance (SAR) and hypertensive response (HR). SA has been implicated as participating in various biotic and abiotic stresses. This study was conducted to investigate the role of SA in adventitious root formation (ARF) in mung bean (Phaseolus radiatus L) hypocotyl cuttings. We observed that hypocotyl treatment with SA could significantly promote the adventitious root formation, and its effects were dose and time dependent. Explants treated with SA displayed a 130% increase in adventitious root number compared with control seedlings. The role of SA in mung bean hypocotyl ARF as well as its interaction with hydrogen peroxide (H2O2) were also elucidated. Pretreatment of mung bean explants with N, N'-dimethylthiourea (DMTU), a scavenger for H2O2, resulted in a significant reduction of SA-induced ARF. Diphenyleneiodonium (DPI), a specific inhibitor of membrane-linked NADPH oxidase, also inhibited the effect of adventitious rooting triggered by SA treatment. The determination of the endogenous H2O2 level indicated that the seedlings treated with SA could induce H2O2 accumulation compared with the control treatment. Our results revealed a distinctive role of SA in the promotion of adventitious rooting via the process of H2O2 accumulation. This conclusion was further supported by antioxidant enzyme activity assays. Based on these results, we conclude that the accumulation of free H2O2 might be a downstream event in response to SA-triggered adventitious root formation in mung bean seedlings.

  7. Hydrogen peroxide is a second messenger in the salicylic acid-triggered adventitious rooting process in mung bean seedlings.

    Directory of Open Access Journals (Sweden)

    Wei Yang

    Full Text Available In plants, salicylic acid (SA is a signaling molecule that regulates disease resistance responses, such as systemic acquired resistance (SAR and hypertensive response (HR. SA has been implicated as participating in various biotic and abiotic stresses. This study was conducted to investigate the role of SA in adventitious root formation (ARF in mung bean (Phaseolus radiatus L hypocotyl cuttings. We observed that hypocotyl treatment with SA could significantly promote the adventitious root formation, and its effects were dose and time dependent. Explants treated with SA displayed a 130% increase in adventitious root number compared with control seedlings. The role of SA in mung bean hypocotyl ARF as well as its interaction with hydrogen peroxide (H2O2 were also elucidated. Pretreatment of mung bean explants with N, N'-dimethylthiourea (DMTU, a scavenger for H2O2, resulted in a significant reduction of SA-induced ARF. Diphenyleneiodonium (DPI, a specific inhibitor of membrane-linked NADPH oxidase, also inhibited the effect of adventitious rooting triggered by SA treatment. The determination of the endogenous H2O2 level indicated that the seedlings treated with SA could induce H2O2 accumulation compared with the control treatment. Our results revealed a distinctive role of SA in the promotion of adventitious rooting via the process of H2O2 accumulation. This conclusion was further supported by antioxidant enzyme activity assays. Based on these results, we conclude that the accumulation of free H2O2 might be a downstream event in response to SA-triggered adventitious root formation in mung bean seedlings.

  8. Establishment of Aquilaria malaccensis Callus, cell suspension and adventitious root systems

    International Nuclear Information System (INIS)

    Aquilaria malaccensis is a tropical forest tree from the family Thymelaeaceae, an endangered forest species and was listed in CITES since 1995. Locally known as Pokok Karas, this tree produces agar wood or gaharu, a highly valuable, resinous and fragrant forest product. Karas has been highly recognized for its vast medicinal values and gaharu has been widely use for perfumery, incense and religious purposes. The phyto chemical studies of agar wood showed that Sesqui terpenoid and Phenyl ethy chromone derivatives are the principal compounds that have anti allergic and anti microbe activities. Cell and organ culture systems provide large scale production of biomass and offers feasibilities for the production of secondary metabolites. This paper describes the work done for establishing reproducible systems for callus initiation and production of cell suspension cultures as well as production of adventitious roots that will later be amenable for the production of secondary metabolites of A. malaccensis. Hence, further manipulation with Methyl Jasmonate, a chemical elicitor could be done to induce secondary metabolites using callus, cell suspension and adventitious roots systems. (author)

  9. The effects of pruning and nodal adventitious roots on polychlorinated biphenyl uptake by Cucurbita pepo grown in field conditions

    International Nuclear Information System (INIS)

    Two cultivation techniques (i-pruning and ii-nodal adventitious root encouragement) were investigated for their ability to increase PCB phytoextraction by Cucurbita pepo ssp pepo cv. Howden (pumpkin) plants in situ at a contaminated industrial site in Ontario (Aroclor 1248, mean soil [PCB] = 5.6 μg g-1). Pruning was implemented to increase plant biomass close to the root where PCB concentration is known to be highest. This treatment was found to have no effect on final shoot biomass or PCB concentration. However, material pruned from the plant is not included in the final shoot biomass. The encouragement of nodal adventitious roots at stem nodes did significantly increase the PCB concentration in the primary stem, while not affecting shoot biomass. Both techniques are easily applied cultivation practices that may be implemented to decrease phytoextraction treatment time. - Research highlights: → Presence of nodal adventitious roots do increase phytoextraction efficiency. → Pruning may increase the biomass of pumpkin plants during phytoextraction. → [Aroclor 1248] decreases in plant tissue with increasing distance from the root. - The application of cultivation practices (pruning and nodal adventitious root encouragement) increases phytoextraction of PCBs in C. pepo.

  10. WHEN STRESS AND DEVELOPMENT GO HAND IN HAND: MAIN HORMONAL CONTROLS OF ADVENTITIOUS ROOTING IN CUTTINGS

    Directory of Open Access Journals (Sweden)

    Cibele Tesser Da Costa

    2013-05-01

    Full Text Available Adventitious rooting (AR is a multifactorial response leading to new roots at the base of stem cuttings, and the establishment of a complete and autonomous plant. AR has two main phases: a induction, with a requirement for higher auxin concentration; b formation, inhibited by high auxin and in which anatomical changes take place. The first stages of this process in severed organs necessarily include wounding and water stress responses which may trigger hormonal changes that contribute to reprogram target cells that are competent to respond to rooting stimuli. At severance, the roles of jasmonate and abscisic acid are critical for wound response and perhaps sink strength establishment, although their negative roles on the cell cycle may inhibit root induction. Strigolactones may also inhibit AR. A reduced cytokinin concentration in cuttings results from the separation of the root system, whose tips are a relevant source of these root induction inhibitors. The combined increased accumulation of basipetally transported auxins from the shoot apex at the cutting base is often sufficient for AR in easy-to-root species. The role of peroxidases and phenolic compounds in auxin catabolism may be critical at these early stages right after wounding. The events leading to AR strongly depend on mother plant nutritional status, both in terms of minerals and carbohydrates, as well as on sink establishment at cutting bases. Auxins play a central role in AR. Auxin transporters control auxin canalization to target cells. There, auxins act primarily through selective proteolysis and cell wall loosening, via their receptor proteins TIR1 and ABP1. A complex microRNA circuitry is involved in the control of auxin response factors essential for gene expression in AR. After root establishment, new hormonal controls take place, with auxins being required at lower concentrations for root meristem maintenance and cytokinins needed for root tissue differentiation.

  11. An Efficient Method for Adventitious Root Induction from Stem Segments of Brassica Species

    Science.gov (United States)

    Srikanth, Sandhya; Choong, Tsui Wei; Yan, An; He, Jie; Chen, Zhong

    2016-01-01

    Plant propagation via in vitro culture is a very laborious and time-consuming process. The growth cycle of some of the crop species is slow even in the field and the consistent commercial production is hard to maintain. Enhanced methods of reduced cost, materials and labor significantly impact the research and commercial production of field crops. In our studies, stem-segment explants of Brassica species were found to generate adventitious roots (AR) in aeroponic systems in less than a week. As such, the efficiency of rooting from stem explants of six cultivar varieties of Brassica spp was tested without using any plant hormones. New roots and shoots were developed from Brassica alboglabra (Kai Lan), B. oleracea var. acephala (purple kale), B. rapa L. ssp. chinensis L (Pai Tsai, Nai Bai C, and Nai Bai T) explants after 3 to 5 days of growing under 20 ± 2°C cool root zone temperature (C-RZT) and 4 to 7 days in 30 ± 2°C ambient root zone temperature (A-RZT). At the base of cut end, anticlinal and periclinal divisions of the cambial cells resulted in secondary xylem toward pith and secondary phloem toward cortex. The continuing mitotic activity of phloem parenchyma cells led to a ring of conspicuous white callus. Root initials formed from the callus which in turn developed into ARs. However, B. rapa var. nipposinica (Mizuna) explants were only able to root in C-RZT. All rooted explants were able to develop into whole plants, with higher biomass obtained from plants that grown in C-RZT. Moreover, explants from both RZTs produced higher biomass than plants grown from seeds (control plants). Rooting efficiency was affected by RZTs and explant cuttings of donor plants. Photosynthetic CO2 assimilation rate (Asat) and stomatal conductance (gssat) were significantly differentiated between plants derived from seeds and explants at both RZTs. All plants in A-RZT had highest transpiration rates. PMID:27446170

  12. Adventitious rooting in cuttings of croton and hibiscus in response to indolbutyric acid and humic acid

    Directory of Open Access Journals (Sweden)

    Lílian Estrela Borges Baldotto

    2012-08-01

    Full Text Available Adventitious rooting of ornamental plants can be accelerated by the application of growth regulators, such as auxin. Humic acids, organic matter in soil and organic compounds also have a biostimulant effect. This work evaluated the rooting in cuttings of croton (Codianeum variegatum L. Rumph and hibiscus (Hibiscus rosa-sinensis L in response to the application of different concentrations of indolbutyric acid (IBA and humic acid (HA. The experiment was carried out in a greenhouse. Apical stem cuttings were treated with solutions at concentrations of: 0, 250, 500, 1000, 2000 mg L-1 IBA and 0, 10, 20, 30, 40 mmol L-1 HA carbon isolated from vermicomposting. Forty-five days after the applications, the cuttings were removed from the pots containing carbonized rice hull and the following variables were measured: rooting number, length and width of leaves, fresh and dry matter of root and aerial part and root area. The results were subjected to analysis of variance and the qualitative and quantitative effects of the treatments were compared by contrast and regression, respectively. Regression equations were used to determine the maximum efficiency level of root dry matter according to IBA and HA. Higher accumulation of root dry matter was recorded for the treatments with the doses 579 mg L-1 IBA and 14 mmol L-1 HA and 970 mg L-1 IBA and 50 mmol L-1 HA for root cuttings of croton and hibiscus, respectively. It was found that the application of eiher IBA or HA at the indicated doses accelerates rooting in cuttings of croton and hibiscus and contributes to the formation of vigorous plants.

  13. An Efficient Method for Adventitious Root Induction from Stem Segments of Brassica Species.

    Science.gov (United States)

    Srikanth, Sandhya; Choong, Tsui Wei; Yan, An; He, Jie; Chen, Zhong

    2016-01-01

    Plant propagation via in vitro culture is a very laborious and time-consuming process. The growth cycle of some of the crop species is slow even in the field and the consistent commercial production is hard to maintain. Enhanced methods of reduced cost, materials and labor significantly impact the research and commercial production of field crops. In our studies, stem-segment explants of Brassica species were found to generate adventitious roots (AR) in aeroponic systems in less than a week. As such, the efficiency of rooting from stem explants of six cultivar varieties of Brassica spp was tested without using any plant hormones. New roots and shoots were developed from Brassica alboglabra (Kai Lan), B. oleracea var. acephala (purple kale), B. rapa L. ssp. chinensis L (Pai Tsai, Nai Bai C, and Nai Bai T) explants after 3 to 5 days of growing under 20 ± 2°C cool root zone temperature (C-RZT) and 4 to 7 days in 30 ± 2°C ambient root zone temperature (A-RZT). At the base of cut end, anticlinal and periclinal divisions of the cambial cells resulted in secondary xylem toward pith and secondary phloem toward cortex. The continuing mitotic activity of phloem parenchyma cells led to a ring of conspicuous white callus. Root initials formed from the callus which in turn developed into ARs. However, B. rapa var. nipposinica (Mizuna) explants were only able to root in C-RZT. All rooted explants were able to develop into whole plants, with higher biomass obtained from plants that grown in C-RZT. Moreover, explants from both RZTs produced higher biomass than plants grown from seeds (control plants). Rooting efficiency was affected by RZTs and explant cuttings of donor plants. Photosynthetic CO2 assimilation rate (Asat ) and stomatal conductance (gssat ) were significantly differentiated between plants derived from seeds and explants at both RZTs. All plants in A-RZT had highest transpiration rates. PMID:27446170

  14. Promoting Roles of Melatonin in Adventitious Root Development of Solanum lycopersicum L. by Regulating Auxin and Nitric Oxide Signaling

    OpenAIRE

    Dan eWen; Biao eGong; Shasha eSun; Shiqi eLiu; Xiufeng eWang; Min eWei; Fengjuan eYang; Yan eLi; Qinghua eShi

    2016-01-01

    Melatonin (MT) plays integral roles in regulating several biological processes including plant growth, seed germination, flowering, senescence and stress responses. This study investigated the effects of MT on adventitious root formation (ARF) of de-rooted tomato seedlings. Exogenous MT positively or negatively influenced ARF, which was dependent on the concentration of MT application. In the present experiment, 50 µM MT showed the best effect on inducing ARF. Interestingly, exogenous MT prom...

  15. Promoting Roles of Melatonin in Adventitious Root Development of Solanum lycopersicum L. by Regulating Auxin and Nitric Oxide Signaling

    OpenAIRE

    Wen, Dan; Gong, Biao; Sun, Shasha; Liu, Shiqi; Wang, Xiufeng; Min WEI; Yang, Fengjuan; Li, Yan; Shi, Qinghua

    2016-01-01

    Melatonin (MT) plays integral roles in regulating several biological processes including plant growth, seed germination, flowering, senescence, and stress responses. This study investigated the effects of MT on adventitious root formation (ARF) of de-rooted tomato seedlings. Exogenous MT positively or negatively influenced ARF, which was dependent on the concentration of MT application. In the present experiment, 50 μM MT showed the best effect on inducing ARF. Interestingly, exogenous MT pro...

  16. Bioreactor with Ipomoea hederifolia adventitious roots and its endophyte Cladosporium cladosporioides for textile dye degradation.

    Science.gov (United States)

    Patil, Swapnil M; Chandanshive, Vishal V; Rane, Niraj R; Khandare, Rahul V; Watharkar, Anuprita D; Govindwar, Sanjay P

    2016-04-01

    In vitro grown untransformed adventitious roots (AR) culture of Ipomoea hederifolia and its endophytic fungus (EF) Cladosporium cladosporioides decolorized Navy Blue HE2R (NB-HE2R) at a concentration of 20 ppm up to 83.3 and 65%, respectively within 96h. Whereas the AR-EF consortium decolorized the dye more efficiently and gave 97% removal within 36h. Significant inductions in the enzyme activities of lignin peroxidase, tyrosinase and laccase were observed in roots, while enzymes like tyrosinase, laccase and riboflavin reductase activities were induced in EF. Metabolites of dye were analyzed using UV-vis spectroscopy, FTIR and gas chromatography-mass spectrometry. Possible metabolic pathways of NB-HE2R were proposed with AR, EF and AR-EF systems independently. Looking at the superior efficacy of AR-EF system, a rhizoreactor was developed for the treatment of NB-HE2R at a concentration of 1000 ppm. Control reactor systems with independently grown AR and EF gave 94 and 85% NB-HE2R removal, respectively within 36h. The AR-EF rhizoreactor, however, gave 97% decolorization. The endophyte colonization additionally increased root and shoot lengths of candidate plants through mutualism. Combined bioreactor strategies can be effectively used for future eco-friendly remediation purposes. PMID:26803212

  17. Pilot-scale culture of Hypericum perforatum L. adventitious roots in airlift bioreactors for the production of bioactive compounds.

    Science.gov (United States)

    Cui, Xi-Hua; Murthy, Hosakatte Niranjana; Paek, Kee-Yoeup

    2014-09-01

    Hypericum perforatum L. (St. John's Wort) is an important medicinal plant which is widely used in the treatment for depression and irritable bowel syndrome. It is also used as a dietary supplement. Major bioactive phytochemicals of H. perforatum are phenolics and flavonoids. Quality of these phytochemicals is dramatically influenced by environmental and biological factors in the field grown plants. As an alternative, we have developed adventitious root cultures in large-scale bioreactors for the production of useful phytochemicals. Adventitious roots of H. perforatum were cultured in 500 l pilot-scale airlift bioreactors using half-strength Murashige and Skoog medium with an ammonium and nitrate ratio of 5:25 mM and supplemented with 1.0 mg l(-1) indole butyric acid, 0.1 mg l(-1) kinetin, and 3 % sucrose for the production of bioactive phenolics and flavonoids. Then 4.6 and 6.3 kg dry biomass were realized in the 500 l each of drum-type and balloon-type bioreactors, respectively. Accumulation of 66.9 mg g(-1) DW of total phenolics, 48.6 mg g(-1) DW of total flavonoids, 1.3 mg g(-1) DW of chlorogenic acid, 0.01 mg g(-1) DW of hyperin, 0.04 mg g(-1) DW of hypericin, and 0.01 mg g(-1) DW of quercetin could be achieved with adventitious roots cultured in 500 l balloon-type airlift bioreactors. Our findings demonstrate the possibilities of using H. perforatum adventitious root cultures for the production of useful phytochemicals to meet the demand of pharmaceutical and food industry.

  18. De novo adventitious root formations in mini-cuttings of Azadirachta indica in response to different rooting media and auxin treatments

    Directory of Open Access Journals (Sweden)

    Gehlot A

    2015-08-01

    Full Text Available Neem (Azadirachta indica A. Juss is a multipurpose Indian tree important to local economy. Conservation of the genetic resources of neem is essential for the adaptability of this tree species to projected climate change impacts. Here, the effect of type and concentration of auxins in different rooting media on adventitious root formation (ARF in mini-cuttings of Azadirachta indica is depicted. Three different rooting media (i.e., sand, vermiculite and soil were used, and the experiment was established using three types of auxin (IBA, IAA and NAA and 6 concentration treatment combinations (100, 250, 500, 750, 1000 and 1500 mg l-1, in a complete randomized block design (CRBD. Significant effects of different auxin types, concentration treatments and rooting media on adventitious root formation of neem mini-cuttings were observed. Mini-cuttings were assessed for rooting percentage, number of roots, root length and number of leaves. IBA resulted in higher rooting percentage (90%, number of roots (149.56, root length (14.83 cm and number of leaves per rooted mini-cuttings (12.78, when growing in sand. The determination of proper rooting protocols and the use of mini-cuttings were proved important for improving mass propagation of A. indica.

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

    Directory of Open Access Journals (Sweden)

    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. Change of Nitric Oxide and NADPH-diaphorase During the Generation and the Development of Adventitious Roots in Mung Bean Hypocotyl Cuttings

    Institute of Scientific and Technical Information of China (English)

    SHEXiao-Ping; HUANGAi-Xia

    2004-01-01

    Effects of nitric oxide (NO) donor sodium nitroprusside (SNP), NO specific scavenger c-PTIO and nitric oxide synthase (NOS) inhibitor L-NAME on the rooting of mung bean ( Vigna radiata L.) hypocotyl cuttings were studied. The spatio-temporal changes of NO and NADPH-diaphorase in the basal part of cutting were also detected during the adventitious rooting process. The results showed that SNP significantly enhanced the adventitious rooting in the range of concentrations tested. NADPH-diaphorase activity (commonly employed as a marker for NOS) and the fluorescence of NO were respectively observed in the zone between the vascular bundles of the basal part of cuttings at 24h and 36h after cutting. The root primordium became discernible at 48h after cutting in the same region, and became more elongate at 60h. NADPH-diaphorase activity and NO fluorescence gradually increased during 48-60h and mainly distributed in root meristem. L-NAME treatment delayed adventitious root emergency and significantly reduced the NADPH-diaphorase staining and the fluorescence of NO. The specific NO scavenger, c-PTIO, also suppressed the fluorescence and inhibited the formation of adventitious roots. These results suggest that endogenous NO appears to play a key role in the generation and development of adventitious roots, and the production of NO in this process may be catalyzed by NOS-like enzyme.

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

    Institute of Scientific and Technical Information of China (English)

    Chengming; Sun; Lijian; Wang; Tao; Liu; Doudou; Guo; Yingying; Chen; Wei; Wu; Yulong; Wang; Jianguo; Zhu

    2014-01-01

    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 Xianyou63. The effects of increasing atmospheric CO2 concentration [CO2], 200 μmol mol-1higher 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.

  2. Plant hormone homeostasis, signaling and function during adventitious root formation in cuttings

    Directory of Open Access Journals (Sweden)

    Uwe eDruege

    2016-03-01

    Full Text Available Adventitious root (AR formation in cuttings is a multiphase developmental process, resulting from wounding at the cutting site and isolation from the resource and signal network of the whole plant. Though promotive effects of auxins are widely used for clonal plant propagation, the regulation and function of plant hormones and their intricate signaling networks during AR formation in cuttings are poorly understood. In this focused review, we discuss our recent publications on the involvement of polar auxin transport (PAT and transcriptional regulation of auxin and ethylene action during AR formation in petunia cuttings in a broad context. Integrating new findings on cuttings of other plant species and general models on plant hormone networks, a model on the regulation and function of auxin, ethylene and jasmonate in AR formation of cuttings is presented. PAT and cutting off from the basipetal auxin drain are considered as initial principles generating early accumulation of IAA in the rooting zone. This is expected to trigger a self-regulatory process of auxin canalization and maximization to responding target cells, there inducing the program of AR formation. Regulation of auxin homeostasis via auxin influx and efflux carriers, GH3 proteins and peroxidases, of flavonoid metabolism and of auxin signaling via AUX/IAA proteins, TOPLESS, ARFs and SAUR-like proteins are postulated as key processes determining the different phases of AR formation. NO and H2O2 mediate auxin signaling via the cGMP and MAPK cascades. Transcription factors of the GRAS-, AP2/ERF- and WOX-families link auxin signaling to cell fate specification. Cyclin-mediated governing of the cell cycle, modifications of sugar metabolism and microtubule and cell wall remodeling are considered as important implementation processes of auxin function. Induced by the initial wounding and other abiotic stress factors, up-regulation of ethylene biosynthesis and signaling via ERFs and early

  3. Liquid Culture of Adventitious Roots is a Potential Alternative to Field Cultivation for Psammosilene tunicoides, a Rare and Endangered Endemic Medicinal Plant

    Directory of Open Access Journals (Sweden)

    Zongshen Zhang

    2013-02-01

    Full Text Available The aim of this study was to establish an adventitious roots culture system for sterile plantlet segments of P. tunicoides and improved the accumulation of total saponins in cultured roots. Psammosilene tunicoides is a native Chinese plant with high commercial value as medicinal herb. Combination of NAA and IBA significantly affected the adventitious roots formation on agar-solided B5 media and a maximal induction rate of 83% was obtained at 24±2°C with a photoperiod of 12 h. With a shaking of 110 rpm in darkness, transferring the detached adventitious roots to the growth regulator free 1/2 B5 liquid media notably increased the biomass production compared to that on solid media over a 30-day-culture period. Further analyses showed that more saponins could be accumulated in the liquid culture than in the solid culture and the addition of exogenous oxalic acid to the liquid media could enhance the accumulation of total saponins in adventitious roots. These results suggested that adventitious roots culture will be an efficient alternative to the field cultivation of intact plants for the production of useful natural compounds from P. tunicoides.

  4. Effect of naphthalene acetic acid on adventitious root development and associated physiological changes in stem cutting of Hemarthria compressa.

    Directory of Open Access Journals (Sweden)

    Yan-Hong Yan

    Full Text Available In order to find a way to induce rooting on cuttings of Hemarthria compressa cv. Ya'an under controlled conditions, a project was carried out to study the effect of naphthalene acetic acid (NAA on rooting in stem cuttings and related physiological changes during the rooting process of Hemarthria compressa. The cuttings were treated with five concentrations of NAA (0, 100, 200 300, 400 mg/l at three soaking durations (10, 20, 30 minutes, and cuttings without treatment were considered as control. Samples were planted immediately into pots after treatment. IAA-oxidase (IAAO activity, peroxidase (POD activity and polyphenol oxidase (PPO activity were determined after planting. Results showed that NAA had positive effect on rooting at the concentration of 200 mg/l compared to other concentrations at 30 days after planting (DAP. Among the three soaking durations, 20 minutes (min of 200 mg/l NAA resulted in higher percentages of rooting, larger numbers of adventitious roots and heavier root dry weight per cutting. The lowest IAAO activity was obtained when soaked at 200 mg/l NAA for 20 min soaking duration. This was consistent with the best rooting ability, indicating that the lower IAAO activity, the higher POD activity and PPO activity could be used as an indicator of better rooting ability for whip grass cuttings and might serve as a good marker for rooting ability in cuttings.

  5. Use of auxin, fungicides and rooting cofactors to induce adventitious root formation in softwood cuttings of apple, gooseberry and some ornamental plants

    Directory of Open Access Journals (Sweden)

    M. G. Piątkowski

    2015-06-01

    Full Text Available Cuttings of apple rootstocks MM 106, Alnarp 2, M VII and M 26, of the ornamental plants Pyracantha coccinea Roem., Syringa Meyeri Schneid., and Weigela cv. Vanhouttei formed a larger numbers of adventitious roots with a mixture of naphthaleneacetic acid and the fungicide Captan than with auxin alone. Boric acid, vitamin B1 as well as pyrogallol and vanilic acid in rather high concentrations showed no effect on rooting when used separately or in a mixture with an auxin. Intermittent mist and bottom heat were used.

  6. Production of biomass and bioactive compounds from adventitious roots by optimization of culturing conditions of Eurycoma longifolia in balloon-type bubble bioreactor system.

    Science.gov (United States)

    Lulu, Tao; Park, So-Young; Ibrahim, Rusli; Paek, Kee-Yoeup

    2015-06-01

    The present study aimed to optimize the conditions for the production of adventitious roots from Eurycoma longifolia Jack, an important medicinal woody plant, in bioreactor culture. The effects of the type and concentration of auxin on root growth were studied, as well as the effects of the NH4(+):NO3(-) ratio on adventitious root growth and the production of phenolics and flavonoids. Approximately 5 g L(-1) fresh weight of adventitious roots was inoculated into a 3 L balloon-type bubble bioreactor, which contained 2 L 3/4 MS medium supplemented with 30 g L(-1) sucrose and cultures were maintained in the dark for 7 weeks at 24 ± 1°C. Higher concentrations of IBA (7.0 and 9.0 mg L(-1)) and NAA (5.0 mg L(-1)) enhanced the biomass and accumulation of total phenolics and flavonoids. The adventitious roots were thin, numerous, and elongated in 3/4 MS medium supplemented with 5.0 and 7.0 mg L(-1) IBA, whereas the lateral roots were shorter and thicker with 5.0 mg L(-1) NAA compared with IBA treatment. The optimum biomasses of 50.22 g L(-1) fresh weight and 4.60 g L(-1) dry weight were obtained with an NH4(+):NO3(-) ratio of 15:30. High phenolic and flavonoid productions (38.59 and 11.27 mg L(-1) medium, respectively) were also obtained with a ratio of 15:30. Analysis of the 2,2-diphenyl-1-picrylhydrazyl (DPPH)-scavenging activity indicated higher antioxidant activity with an NH4(+):NO3(-) ratio of 30:15. These results suggest that balloon-type bubble bioreactor cultures are suitable for the large-scale commercial production of E. longifolia adventitious roots which contain high yield of bioactive compounds.

  7. Adventitious root formation in rice requires OsGNOM1 and is mediated by the OsPINs family

    Institute of Scientific and Technical Information of China (English)

    Shiping Liu; Jirong Wang; Lu Wang; Xiaofei Wang; Yanhong Xue; Ping Wu; Huixia Shou

    2009-01-01

    The fibrous root system in cereals comprises primarily adventitious roots (ARs), which play important roles in nu-trient and water uptake. Current knowledge regarding the molecular mechanism underlying AR development is still limited. We report here the isolation of four rice (Oryza sativa L.) mutants, from different genetic backgrounds, all of which were defective in AR formation. These mutants exhibited reduced numbers of lateral roots (LRs) and partial loss of gravitropism. The mutants also displayed enhanced sensitivity to N-1-napbthylphthalamic acid, an inhibitor of polar auxin transport (PAT), indicating that the mutations affected auxin transport. Positional cloning using one of the four mutants revealed that it was caused by loss-of-function of a guanine nucleotide exchange factor for ADP-ribosylation factor (OsGNOM1). RT-PCR and analysis of promoter::GUS transgenic plants showed that OsGNOM1 is expressed in AR primordia, vascular tissues, LRs, root tips, leaves, anthers and lemma veins, with a distribution pattern similar to that of auxin. In addition, the expressions of OsPIN2, OsPINSb and OsPIN9 were altered in the mu-tants. Taken together, these findings indicate that OsGNOM1 affects the formation of ARs through regulating PAT.

  8. Effect of Naphthalene Acetic Acid on the Adventitious Rooting in Shoot Cuttings of Andrographis paniculata (Burm.f. Wall. ex Nees: An Important Therapeutical Herb

    Directory of Open Access Journals (Sweden)

    Md. Sanower Hossain

    2016-01-01

    Full Text Available Andrographis paniculata is one of the most important therapeutical herbs, widely used in traditional medical systems for the treatment of diverse diseases for thousands of years. This study was carried out to assess the effect of 1-naphthaleneacetic acid (NAA on adventitious rooting in A. paniculata shoot cuttings. The cuttings were treated with six concentrations of NAA (0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 mM by applying soaking method and cuttings without hormone (soaking in distilled water were considered as control. The cuttings were then inoculated into peat moss in the planting tray and incubated under complete shade for root induction. Water was sprayed on peat moss once daily to moisten it. The results showed that different concentrations of NAA significantly (P≤0.05 affected the rooting characteristics of A. paniculata and 2.5 mM of NAA was found to be more effective to induce rooting in young apical shoot (YAS cuttings compared to other concentrations and old apical shoot (OAS. This study also postulates that adventitious rooting response depends on the juvenility of plant material and concentration of growth regulator. This report describes a technique for adventitious rooting in A. paniculata, which could be feasible to use for commercial scale propagation of this plant.

  9. 太子参不定根组织培养的研究%Study on tissue cultivation of adventitious roots of Pseudoxtellariae heterophylla

    Institute of Scientific and Technical Information of China (English)

    梁玉勇; 尹双双; 左北梅; 高文远

    2012-01-01

    Objective: To systematically optimize the cultivation conditions of adventitious roots of Pseudoxtellariae heterophylla. Method: Tissue cultivation technology and ultraviolet spectrophotometry were adopted to observe the effect of inoculum volume, sucrose concentration, inorganic salt concentration, number of cultivation days, gradual scale-up cultivation and bubble different angles of bioreactor on the growth of adventitious roots of P. heterophylla, and determine the content of constituents such as saponin, polysaccha-ride and amino acid. Result: The propagation multiple of adventitious roots reached the maximum when the inoculum was 6 g in a 1 L culture shake flask. With the increase in sucrose concentration, the dry weight propagation multiples of adventitious roots followed an up and down trend. The inorganic salt concentration in a cultivation dish had a greater effect on the growth of adventitious roots, particularly 3/4 MS was the most favorable for the growth of adventitious roots. The growth curve of P. heterophylla was " S" , with the bio-mass reaching the maximum at the 28th day. Conclusion: The inoculum volume, sucrose concentration, inorganic salt concentration, gradual scale-up cultivation and angles of bubble bioreactor had a significant effect on the growth of adventitious roots of P. heterophylla. The contents of saponin and amino acid in adventitious roots were higher than that in cultivated P. heterophylla, whereas the poly-saccharide content were lower than that in cultivated P. heterophylla.%目的:对太子参不定根的培养条件进行系统的优化.方法:利用组织培养技术结合紫外分光光度法,考察了接种量、蔗糖浓度、无机盐浓度、培养天数、逐级扩大培养以及不同角度鼓泡式反应器对太子参不定根生长的影响,并对不定根中皂苷、多糖和氨基酸等成分进行含量测定.结果:每1L培养基接种的不定根鲜重为6 g时,太子参不定根的干重增殖倍数达到

  10. A higher sink competitiveness of the rooting zone and invertases are involved in dark stimulation of adventitious root formation in Petunia hybrida cuttings.

    Science.gov (United States)

    Klopotek, Yvonne; Franken, Philipp; Klaering, Hans-Peter; Fischer, Kerstin; Hause, Bettina; Hajirezaei, Mohammad-Reza; Druege, Uwe

    2016-02-01

    The contribution of carbon assimilation and allocation and of invertases to the stimulation of adventitious root formation in response to a dark pre-exposure of petunia cuttings was investigated, considering the rooting zone (stem base) and the shoot apex as competing sinks. Dark exposure had no effect on photosynthesis and dark respiration during the subsequent light period, but promoted dry matter partitioning to the roots. Under darkness, higher activities of cytosolic and vacuolar invertases were maintained in both tissues when compared to cuttings under light. This was partially associated with higher RNA levels of respective genes. However, activity of cell wall invertases and transcript levels of one cell wall invertase isogene increased specifically in the stem base during the first two days after cutting excision under both light and darkness. During five days after excision, RNA accumulation of four invertase genes indicated preferential expression in the stem base compared to the apex. Darkness shifted the balance of expression of one cytosolic and two vacuolar invertase genes towards the stem base. The results indicate that dark exposure before planting enhances the carbon sink competitiveness of the rooting zone and that expression and activity of invertases contribute to the shift in carbon allocation. PMID:26795147

  11. Transcriptomic analysis reveals ethylene as stimulator and auxin as regulator of adventitious root formation in petunia cuttings

    Directory of Open Access Journals (Sweden)

    Uwe eDruege

    2014-09-01

    Full Text Available Adventitious root (AR formation in the stem base of cuttings is the basis for propagation of many plant species and petunia is used as model to study this developmental process. Following AR formation from 2 to 192 hours after excision (hpe of cuttings, transcriptome analysis by microarray revealed a change of the character of the rooting zone from stem base to root identity. The greatest shift in the number of differentially expressed genes was observed between 24 and 72 hpe, when the categories storage, mineral nutrient acquisition, anti-oxidative and secondary metabolism, and biotic stimuli showed a notable high number of induced genes. Analyses of phytohormone-related genes disclosed multifaceted changes of the auxin transport system, auxin conjugation and the auxin signal perception machinery indicating a reduction in auxin sensitivity and phase-specific responses of particular auxin-regulated genes. Genes involved in ethylene biosynthesis and action showed a more uniform pattern as a high number of respective genes were generally induced during the whole process of AR formation. The important role of ethylene for stimulating AR formation was demonstrated by the application of inhibitors of ethylene biosynthesis and perception as well as of the precursor aminocyclopropane-1-carboxylic acid, all changing the number and length of AR. A model is proposed showing the putative role of polar auxin transport and resulting auxin accumulation in initiation of subsequent changes in auxin homeostasis and signal perception with a particular role of Aux/IAA expression. These changes might in turn guide the entrance into the different phases of AR formation. Ethylene biosynthesis, which is stimulated by wounding and does probably also respond to other stresses and auxin, acts as important stimulator of AR formation probably via the expression of ethylene responsive transcription factor genes, whereas the timing of different phases seems to be controlled

  12. Transcriptome Analysis of Methyl Jasmonate-Elicited Panax ginseng Adventitious Roots to Discover Putative Ginsenoside Biosynthesis and Transport Genes

    Directory of Open Access Journals (Sweden)

    Hongzhe Cao

    2015-01-01

    Full Text Available The Panax ginseng C.A. Meyer belonging to the Araliaceae has long been used as an herbal medicine. Although public databases are presently available for this family, no methyl jasmonate (MeJA elicited transcriptomic information was previously reported on this species, with the exception of a few expressed sequence tags (ESTs using the traditional Sanger method. Here, approximately 53 million clean reads of adventitious root transcriptome were separately filtered via Illumina HiSeq™2000 from two samples treated with MeJA (Pg-MeJA and equal volumes of solvent, ethanol (Pg-Con. Jointly, a total of 71,095 all-unigenes from both samples were assembled and annotated, and based on sequence similarity search with known proteins, a total of 56,668 unigenes was obtained. Out of these annotated unigenes, 54,920 were assigned to the NCBI non-redundant protein (Nr database, 35,448 to the Swiss-prot database, 43,051 to gene ontology (GO, and 19,986 to clusters of orthologous groups (COG. Searching in the Kyoto encyclopedia of genes and genomes (KEGG pathway database indicated that 32,200 unigenes were mapped to 128 KEGG pathways. Moreover, we obtained several genes showing a wide range of expression levels. We also identified a total of 749 ginsenoside biosynthetic enzyme genes and 12 promising pleiotropic drug resistance (PDR genes related to ginsenoside transport.

  13. Comprehensive transcriptome analysis unravels the existence of crucial genes regulating primary metabolism during adventitious root formation in Petunia hybrida.

    Directory of Open Access Journals (Sweden)

    Amirhossein Ahkami

    Full Text Available To identify specific genes determining the initiation and formation of adventitious roots (AR, a microarray-based transcriptome analysis in the stem base of the cuttings of Petunia hybrida (line W115 was conducted. A microarray carrying 24,816 unique, non-redundant annotated sequences was hybridized to probes derived from different stages of AR formation. After exclusion of wound-responsive and root-regulated genes, 1,354 of them were identified which were significantly and specifically induced during various phases of AR formation. Based on a recent physiological model distinguishing three metabolic phases in AR formation, the present paper focuses on the response of genes related to particular metabolic pathways. Key genes involved in primary carbohydrate metabolism such as those mediating apoplastic sucrose unloading were induced at the early sink establishment phase of AR formation. Transcriptome changes also pointed to a possible role of trehalose metabolism and SnRK1 (sucrose non-fermenting 1- related protein kinase in sugar sensing during this early step of AR formation. Symplastic sucrose unloading and nucleotide biosynthesis were the major processes induced during the later recovery and maintenance phases. Moreover, transcripts involved in peroxisomal beta-oxidation were up-regulated during different phases of AR formation. In addition to metabolic pathways, the analysis revealed the activation of cell division at the two later phases and in particular the induction of G1-specific genes in the maintenance phase. Furthermore, results point towards a specific demand for certain mineral nutrients starting in the recovery phase.

  14. Promoting Roles of Melatonin in Adventitious Root Development of Solanum lycopersicum L. by Regulating Auxin and Nitric Oxide Signaling

    Directory of Open Access Journals (Sweden)

    Dan eWen

    2016-05-01

    Full Text Available Melatonin (MT plays integral roles in regulating several biological processes including plant growth, seed germination, flowering, senescence and stress responses. This study investigated the effects of MT on adventitious root formation (ARF of de-rooted tomato seedlings. Exogenous MT positively or negatively influenced ARF, which was dependent on the concentration of MT application. In the present experiment, 50 µM MT showed the best effect on inducing ARF. Interestingly, exogenous MT promoted the accumulation of endogenous nitric oxide (NO by down-regulating the expression of S-nitrosoglutathione reductase (GSNOR. To determine the interaction of MT and NO in ARF, MT synthesis inhibitor p-chlorophenylalanine, NO scavenger 2-(4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide potassium salt as well as GSNOR-overexpression plants with low NO levels were used. The function of MT was removed by NO scavenger or GSNOR-overexpression plants. However, application of MT synthesis inhibitor did little to abolish the function of NO. These results indicate that NO, as a downstream signal, was involved in the MT-induced ARF. Concentrations of indole-3-acetic acid and indole-3-butyric acid, as well as the expression of several genes related to the auxin signaling pathway (PIN1, PIN3, PIN7, IAA19 and IAA24, showed that MT influenced auxin transport and signal transduction as well as auxin accumulation through the NO signaling pathway. Collectively, these strongly suggest that elevated NO levels resulting from inhibited GSNOR activity and auxin signaling were involved in the MT-induced ARF in tomato plants. This can be applied in basic research and breeding.

  15. Promoting Roles of Melatonin in Adventitious Root Development of Solanum lycopersicum L. by Regulating Auxin and Nitric Oxide Signaling.

    Science.gov (United States)

    Wen, Dan; Gong, Biao; Sun, Shasha; Liu, Shiqi; Wang, Xiufeng; Wei, Min; Yang, Fengjuan; Li, Yan; Shi, Qinghua

    2016-01-01

    Melatonin (MT) plays integral roles in regulating several biological processes including plant growth, seed germination, flowering, senescence, and stress responses. This study investigated the effects of MT on adventitious root formation (ARF) of de-rooted tomato seedlings. Exogenous MT positively or negatively influenced ARF, which was dependent on the concentration of MT application. In the present experiment, 50 μM MT showed the best effect on inducing ARF. Interestingly, exogenous MT promoted the accumulation of endogenous nitric oxide (NO) by down-regulating the expression of S-nitrosoglutathione reductase (GSNOR). To determine the interaction of MT and NO in ARF, MT synthesis inhibitor p-chlorophenylalanine, NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide potassium salt as well as GSNOR-overexpression plants with low NO levels were used. The function of MT was removed by NO scavenger or GSNOR-overexpression plants. However, application of MT synthesis inhibitor did little to abolish the function of NO. These results indicate that NO, as a downstream signal, was involved in the MT-induced ARF. Concentrations of indole-3-acetic acid and indole-3-butyric acid, as well as the expression of several genes related to the auxin signaling pathway (PIN1, PIN3, PIN7, IAA19, and IAA24), showed that MT influenced auxin transport and signal transduction as well as auxin accumulation through the NO signaling pathway. Collectively, these strongly suggest that elevated NO levels resulting from inhibited GSNOR activity and auxin signaling were involved in the MT-induced ARF in tomato plants. This can be applied in basic research and breeding. PMID:27252731

  16. Changes in endogenous hormone levels and redox status during enhanced adventitious rooting by rare earth element neodymium of Dendrobium densiflorum shoot cuttings

    Institute of Scientific and Technical Information of China (English)

    LUO Jianping; ZHANG Jingcheng; WANG Ying

    2008-01-01

    The effects of neodymium nitrate (Nd3+) on the adventitious rooting of Dendrobium densiflorum shoot cuttings were studied. The addition of Nd3+ (5 μmol/L) to culture medium significantly increased rooting frequency. Histological investigation showed that Nd3+ did not change the process of root initiation. Nd3+ did not influence total endogenous cytokinin levels, but significantly increased the level of en-dogenous indole-3-acetic acid (IAA) in the base of shoot cuttings. Compared to the control, the ratio of IAA/cytokinins was very high in the Nd3+ treatment. These results suggested that the enhanced rooting frequency may be related to the increase in endogenous IAA level in Nd3+ treatment. Analysis of enzyme activities showed that the enhanced accumulation of the endogenous IAA by Nd3+ should not be attributed to inhibition of IAA decomposition by IAA oxidase or promotion of cytokinin decomposition by cytokinin oxidase. Besides, Nd3+ increased the ratio of reduced glutathione (GSH) and oxidized glutathione (GSSG) in the process of adventitious rooting while the ratio of ascorbate (ASC) to dehydroascorbate (DHA) was not affected.

  17. Physiologic responses and gene diversity indicate olive alternative oxidase as a potential source for markers involved in efficient adventitious root induction.

    Science.gov (United States)

    Santos Macedo, Elisete; Cardoso, Hélia G; Hernández, Alejandro; Peixe, Augusto A; Polidoros, Alexios; Ferreira, Alexandre; Cordeiro, António; Arnholdt-Schmitt, Birgit

    2009-12-01

    Olive (Olea europaea L.) trees are mainly propagated by adventitious rooting of semi-hardwood cuttings. However, efficient commercial propagation of valuable olive tree cultivars or landraces by semi-hardwood cuttings can often be restricted by a low rooting capacity. We hypothesize that root induction is a plant cell reaction linked to oxidative stress and that activity of stress-induced alternative oxidase (AOX) is importantly involved in adventitious rooting. To identify AOX as a source for potential functional marker sequences that may assist tree breeding, genetic variability has to be demonstrated that can affect gene regulation. The paper presents an applied, multidisciplinary research approach demonstrating first indications of an important relationship between AOX activity and differential adventitious rooting in semi-hardwood cuttings. Root induction in the easy-to-root Portuguese cultivar 'Cobrançosa' could be significantly reduced by treatment with salicyl-hydroxamic acid, an inhibitor of AOX activity. On the contrary, treatment with H2O2 or pyruvate, both known to induce AOX activity, increased the degree of rooting. Recently, identification of several O. europaea (Oe) AOX gene sequences has been reported from our group. Here we present for the first time partial sequences of OeAOX2. To search for polymorphisms inside of OeAOX genes, partial OeAOX2 sequences from the cultivars 'Galega vulgar', 'Cobrançosa' and 'Picual' were cloned from genomic DNA and cDNA, including exon, intron and 3'-untranslated regions (3'-UTRs) sequences. The data revealed polymorphic sites in several regions of OeAOX2. The 3'-UTR was the most important source for polymorphisms showing 5.7% of variability. Variability in the exon region accounted 3.4 and 2% in the intron. Further, analysis performed at the cDNA from microshoots of 'Galega vulgar' revealed transcript length variation for the 3'-UTR of OeAOX2 ranging between 76 and 301 bp. The identified polymorphisms and 3'-UTR

  18. Enhancement of anti-inflammatory activity of Aloe vera adventitious root extracts through the alteration of primary and secondary metabolites via salicylic acid elicitation.

    Science.gov (United States)

    Lee, Yun Sun; Ju, Hyun Kyoung; Kim, Yeon Jeong; Lim, Tae-Gyu; Uddin, Md Romij; Kim, Yeon Bok; Baek, Jin Hong; Kwon, Sung Won; Lee, Ki Won; Seo, Hak Soo; Park, Sang Un; Yang, Tae-Jin

    2013-01-01

    Aloe vera (Asphodeloideae) is a medicinal plant in which useful secondary metabolites are plentiful. Among the representative secondary metabolites of Aloe vera are the anthraquinones including aloe emodin and chrysophanol, which are tricyclic aromatic quinones synthesized via a plant-specific type III polyketide biosynthesis pathway. However, it is not yet clear which cellular responses can induce the pathway, leading to production of tricyclic aromatic quinones. In this study, we examined the effect of endogenous elicitors on the type III polyketide biosynthesis pathway and identified the metabolic changes induced in elicitor-treated Aloe vera adventitious roots. Salicylic acid, methyl jasmonate, and ethephon were used to treat Aloe vera adventitious roots cultured on MS liquid media with 0.3 mg/L IBA for 35 days. Aloe emodin and chrysophanol were remarkably increased by the SA treatment, more than 10-11 and 5-13 fold as compared with untreated control, respectively. Ultra-performance liquid chromatography-electrospray ionization mass spectrometry analysis identified a total of 37 SA-induced compounds, including aloe emodin and chrysophanol, and 3 of the compounds were tentatively identified as tricyclic aromatic quinones. Transcript accumulation analysis of polyketide synthase genes and gas chromatography mass spectrometry showed that these secondary metabolic changes resulted from increased expression of octaketide synthase genes and decreases in malonyl-CoA, which is the precursor for the tricyclic aromatic quinone biosynthesis pathway. In addition, anti-inflammatory activity was enhanced in extracts of SA-treated adventitious roots. Our results suggest that SA has an important role in activation of the plant specific-type III polyketide biosynthetic pathway, and therefore that the efficacy of Aloe vera as medicinal agent can be improved through SA treatment.

  19. Enhancement of anti-inflammatory activity of Aloe vera adventitious root extracts through the alteration of primary and secondary metabolites via salicylic acid elicitation.

    Directory of Open Access Journals (Sweden)

    Yun Sun Lee

    Full Text Available Aloe vera (Asphodeloideae is a medicinal plant in which useful secondary metabolites are plentiful. Among the representative secondary metabolites of Aloe vera are the anthraquinones including aloe emodin and chrysophanol, which are tricyclic aromatic quinones synthesized via a plant-specific type III polyketide biosynthesis pathway. However, it is not yet clear which cellular responses can induce the pathway, leading to production of tricyclic aromatic quinones. In this study, we examined the effect of endogenous elicitors on the type III polyketide biosynthesis pathway and identified the metabolic changes induced in elicitor-treated Aloe vera adventitious roots. Salicylic acid, methyl jasmonate, and ethephon were used to treat Aloe vera adventitious roots cultured on MS liquid media with 0.3 mg/L IBA for 35 days. Aloe emodin and chrysophanol were remarkably increased by the SA treatment, more than 10-11 and 5-13 fold as compared with untreated control, respectively. Ultra-performance liquid chromatography-electrospray ionization mass spectrometry analysis identified a total of 37 SA-induced compounds, including aloe emodin and chrysophanol, and 3 of the compounds were tentatively identified as tricyclic aromatic quinones. Transcript accumulation analysis of polyketide synthase genes and gas chromatography mass spectrometry showed that these secondary metabolic changes resulted from increased expression of octaketide synthase genes and decreases in malonyl-CoA, which is the precursor for the tricyclic aromatic quinone biosynthesis pathway. In addition, anti-inflammatory activity was enhanced in extracts of SA-treated adventitious roots. Our results suggest that SA has an important role in activation of the plant specific-type III polyketide biosynthetic pathway, and therefore that the efficacy of Aloe vera as medicinal agent can be improved through SA treatment.

  20. Effect of Naphthalene Acetic Acid on the Adventitious Rooting in Shoot Cuttings of Andrographis paniculata (Burm.f.) Wall. ex Nees: An Important Therapeutical Herb

    OpenAIRE

    Md. Sanower Hossain; Zannat Urbi

    2016-01-01

    Andrographis paniculata is one of the most important therapeutical herbs, widely used in traditional medical systems for the treatment of diverse diseases for thousands of years. This study was carried out to assess the effect of 1-naphthaleneacetic acid (NAA) on adventitious rooting in A. paniculata shoot cuttings. The cuttings were treated with six concentrations of NAA (0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 mM) by applying soaking method and cuttings without hormone (soaking in distilled water)...

  1. Direct reprogramming of adult somatic cells towards adventitious root formation in forest tree species: the effect of the juvenile-adult transition

    Directory of Open Access Journals (Sweden)

    Carmen eDiaz-Sala

    2014-07-01

    Full Text Available Cellular plasticity refers, among others, to the capability of differentiated cells to switch the differentiation process and acquire new fates. One way by which plant cell plasticity is manifested is through de novo regeneration of organs from somatic differentiated cells in an ectopic location. However, switching the developmental program of adult cells prior to organ regeneration is difficult in many plant species, especially in forest tree species. In these species, a decline in the capacity to regenerate shoots, roots or embryos from somatic differentiated cells is associated with tree age and maturation. The decline in the ability to form adventitious roots from stem cuttings is one of the most dramatic effects of maturation, and has been the subject of investigations on the basic nature of the process. Cell fate switches, both in plants and animals, are characterized by remarkable changes in the pattern of gene expression, as cells switch from the characteristic expression pattern of a somatic cell to a new one directing a new developmental pathway. Therefore, determining the way by which cells reset their gene expression pattern is crucial to understand cellular plasticity. The presence of specific cellular signalling pathways or tissue-specific factors underlying the establishment, maintenance and redirection of gene expression patterns in the tissues involved in adventitious root formation could be crucial for cell fate switch and for the control of age-dependent cellular plasticity.

  2. Reference gene selection for quantitative reverse transcription-polymerase chain reaction normalization during in vitro adventitious rooting in Eucalyptus globulus Labill

    Directory of Open Access Journals (Sweden)

    Pasquali Giancarlo

    2010-09-01

    Full Text Available Abstract Background Eucalyptus globulus and its hybrids are very important for the cellulose and paper industry mainly due to their low lignin content and frost resistance. However, rooting of cuttings of this species is recalcitrant and exogenous auxin application is often necessary for good root development. To date one of the most accurate methods available for gene expression analysis is quantitative reverse transcription-polymerase chain reaction (qPCR; however, reliable use of this technique requires reference genes for normalization. There is no single reference gene that can be regarded as universal for all experiments and biological materials. Thus, the identification of reliable reference genes must be done for every species and experimental approach. The present study aimed at identifying suitable control genes for normalization of gene expression associated with adventitious rooting in E. globulus microcuttings. Results By the use of two distinct algorithms, geNorm and NormFinder, we have assessed gene expression stability of eleven candidate reference genes in E. globulus: 18S, ACT2, EF2, EUC12, H2B, IDH, SAND, TIP41, TUA, UBI and 33380. The candidate reference genes were evaluated in microccuttings rooted in vitro, in presence or absence of auxin, along six time-points spanning the process of adventitious rooting. Overall, the stability profiles of these genes determined with each one of the algorithms were very similar. Slight differences were observed in the most stable pair of genes indicated by each program: IDH and SAND for geNorm, and H2B and TUA for NormFinder. Both programs indentified UBI and 18S as the most variable genes. To validate these results and select the most suitable reference genes, the expression profile of the ARGONAUTE1 gene was evaluated in relation to the most stable candidate genes indicated by each algorithm. Conclusion Our study showed that expression stability varied between putative reference genes

  3. 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.

  4. 沙棘微扦插不定根发生的形态解剖学研究%Morphological and anatomical features during the formation of adventitious roots of sea buckthorn by micro-cuttage multiplication

    Institute of Scientific and Technical Information of China (English)

    姚景瀚; 李伟

    2013-01-01

    利用石蜡切片法对沙棘微扦插不定根的发生进行形态解剖学研究.结果表明:沙棘属于诱导型生根,观察到其不定根原基起源于2个区域,一部分根原基起源于维管形成层细胞,另一部分起源于韧皮部薄壁细胞区域.沙棘不定根原基继续发育时,一部分沿射线向外生长,另一部分向外生长的同时会与茎段的髓连接起来,这种现象在其他树种中尚未发现.沙棘插穗不定根的发生整体上可分为4个阶段:1)维管形成层细胞和韧皮部薄壁细胞分裂出一些排列紧密、细胞质浓、具有分生组织特点的薄壁细胞团;2)新形成的薄壁细胞团不断分裂并且脱分化,形成具有很强分生能力的不定根原基发端细胞;3)根原基发端细胞继续分裂,沿着射线向远离轴心的方向伸展,从而形成根原基;4)根原基穿过韧皮射线和皮层,向外继续朝皮孔方向发展,最终从皮孔伸出形成不定根,不定根伸出皮孔前内部维管系统发育完善并与茎部维管系统相连接.%Morphological and anatomical features were observed during the formation of adventitious roots of sea buckthorn by micro-cuttage multiplication with paraffin method. The results showed that adventitious root primordium originated from two areas ( one was cell of vascular cambium, and the other was cell from cortex parenchyma) was inductive root formation type. When the adventitious root of sea buckthorn continued to grow, this phenomenon that one of its part extended out in ray direction and the other part would connect with the marrow of stem while it was stretching out remained undiscovered in other species. In general, formation of adventitious root of sea buckthorn can be divided into four stages: 1 ) The cells of cortex parenchyma and vascular cambium divided into parenchyma cell groups which contained the characteristics of meristem, stood in a line and bore dense cytoplasm concentration. 2 ) Newly formed parenchyma

  5. Iron oxidation on the surface of adventitious roots and its relation to aerenchyma formation in rice genotypes

    Directory of Open Access Journals (Sweden)

    Marquel Jonas Holzschuh

    2014-02-01

    Full Text Available Establishment of the water layer in an irrigated rice crop leads to consumption of free oxygen in the soil which enters in a chemical reduction process mediated by anaerobic microorganisms, changing the crop environment. To maintain optimal growth in an environment without O2, rice plants develop pore spaces (aerenchyma that allow O2 transport from air to the roots. Carrying capacity is determined by the rice genome and it may vary among cultivars. Plants that have higher capacity for formation of aerenchyma should theoretically carry more O2 to the roots. However, part of the O2 that reaches the roots is lost due to permeability of the roots and the O2 gradient created between the soil and roots. The O2 that is lost to the outside medium can react with chemically reduced elements present in the soil; one of them is iron, which reacts with oxygen and forms an iron plaque on the outer root surface. Therefore, evaluation of the iron plaque and of the formation of pore spaces on the root can serve as a parameter to differentiate rice cultivars in regard to the volume of O2 transported via aerenchyma. An experiment was thus carried out in a greenhouse with the aim of comparing aerenchyma and iron plaque formation in 13 rice cultivars grown in flooded soils to their formation under growing conditions similar to a normal field, without free oxygen. The results indicated significant differences in the volume of pore spaces in the roots among cultivars and along the root segment in each cultivar, indicating that under flooded conditions the genetic potential of the plant is crucial in induction of cell death and formation of aerenchyma in response to lack of O2. In addition, the amount of Fe accumulated on the root surface was different among genotypes and along the roots. Thus, we concluded that the rice genotypes exhibit different responses for aerenchyma formation, oxygen release by the roots and iron plaque formation, and that there is a direct

  6. Biochemical Status of Stock Plants and Their Annual Sprouts as a Crucial Key for Successful Adventitious Root Formation

    Directory of Open Access Journals (Sweden)

    Gregor OSTERC

    2015-04-01

    Full Text Available Leafy cuttings of Prunus subhirtella Miq. ‘Autumnalis’ were harvested from mature, semi-mature and juvenile stock plants at four dates during the vegetative period 2011 (on 16th of May, on 30th of May, on 20th of June and on 11th of July and their auxin levels (IAA, IAA-Asp and sugar content (glucose, sucrose, sorbitol were quantified. The IAA and IAA-Asp contents in cutting bases increased over the vegetative period, whereby aspartate values were higher than IAA values. The IAA-Asp values ranged from 6.3 µg g-1 to 22.7 µg g-1 FW and reached two great peaks on 30th of May and on 11th of July. The IAA values ranged from 0.29 µg g-1 to 4.51 µg g-1 FW, reaching a small fall on 20th of June. Significantly higher levels of IAA and IAA-Asp were measured at the base of mature cuttings compared to cuttings of semi-mature and juvenile origin, when the cuttings were harvested on 30th of May and on 11th of July. On the other hand, mature leafy cuttings accumulated significantly less fructose and glucose in their root emergence zone (16.3 g kg-1 DW, 45.2 g kg-1 DW compared to semi-mature cuttings (26.4 g kg-1 DW, 62.5 g kg-1 DW and juvenile cuttings (27.3 g kg-1 DW, 73.9 g kg-1 DW. All measured rooting parameters (rooting success, number of main roots and root length were significantly improved when cuttings of a more juvenile origin (semi-mature and juvenile were used.

  7. Influence of cytokinins, basal media and pH on adventitious shoot regeneration from excised root cultures of Albizia lebbeck

    Institute of Scientific and Technical Information of China (English)

    Shahnaz Perveen; Ankita Varshney; Mohammad Anis; Ibrahim M.Aref

    2011-01-01

    A highly reproducible and efficient in vitro shoot regeneration system was developed in a potential medicinal plant, Albizia lebbeck using root explants. Root explanns from 15 day-old-aseptic seedlings were cultured on Murashige and Skoog (MS) medium supplemented with different concentrations (0.5, 2.5, 5.0, 7.5 and 10.0 μM) of 6-Benzyladenine (BA),Kinetin (Kn), 2-lsopentenyl adenine (2-iP) singly as well as in combination with α-Naphthalene acetic acid (NAA) (0.1, 0.5, 1.0, 1.5 and 2.0 μM). The highest rate of shoot multiplication (16.0 ± 1.87 for the average shoot number and 5.16 ± 0.38 cm for shoot length) was achieved on MS medium supplemented with 7.5 tM BA and 0.5 tM NAA. The effects of medium type, medium strength, pH and subculture on shoot induction and proliferation were also tested. An average of 21.6±2.87 shoots per explants could be obtained following this protocol. Rooting was achieved on microshoots using half strength MS medium with 2.0 μM Indole-3-butyric acid (IBA) after four weeks of culture. The in vitro raised healthy plantlets were successfully established in earthen pots containing garden soil and grown in greenhouse with >80% survival rate.

  8. Production of the Quinone-Methide Triterpene Maytenin by In Vitro Adventitious Roots of Peritassa campestris (Cambess. A.C.Sm. (Celastraceae and Rapid Detection and Identification by APCI-IT-MS/MS

    Directory of Open Access Journals (Sweden)

    Tiago Antunes Paz

    2013-01-01

    Full Text Available Establishment of adventitious root cultures of Peritassa campestris (Celastraceae was achieved from seed cotyledons cultured in semisolid Woody Plant Medium (WPM supplemented with 2% sucrose, 0.01% PVP, and 4.0 mg L−1 IBA. Culture period on accumulation of biomass and quinone-methide triterpene maytenin in adventitious root were investigated. The accumulation of maytenin in these roots was compared with its accumulation in the roots of seedlings grown in a greenhouse (one year old. A rapid detection and identification of maytenin by direct injection into an atmospheric-pressure chemical ionization ion trap tandem mass spectrometer (APCI-IT-MS/MS were performed without prior chromatographic separation. In vitro, the greatest accumulation of biomass occurred within 60 days of culture. The highest level of maytenin—972.11 μg·g−1 dry weight—was detected at seven days of cultivation; this value was 5.55-fold higher than that found in the roots of seedlings grown in a greenhouse.

  9. 白色紫锥菊不定根诱导及咖啡酸衍生物积累研究%Induction of adventitious roots of Echinacea pallida and accumulation of caffeic acid derivatives

    Institute of Scientific and Technical Information of China (English)

    吴春华; 黄韬; 崔锡花; 白基烨

    2012-01-01

    以白色紫锥菊试管苗子叶为外植体,研究了植物生长素2,4-D,IAA,IBA,NAA对不定根诱导以及IBA浓度对液体悬浮培养中不定根的生长及咖啡酸衍生物积累的影响,并进行了生物反应器培养.结果表明,对白色紫锥不定根诱导最适合植物生长素是IBA1.0mg· L-1,不定根诱导数目达到22.5根/培养皿.液体悬浮培养中IBA 1.0 mg·L-1最适合不定根生长及咖啡酸衍生物的积累.白色紫锥菊不定根在5L气升式生物反应器中培养30 d后可获得8.98 g· L-1干重,是三角瓶悬浮培养干重4.38 g·L-1的2.05倍;生物反应器培养的不定根中紫锥菊苷质量分数为14.08 mg·g-1(干重),是栽培根的2.4倍;氯原酸,菊苣酸,总咖啡酸衍生物含量是栽培根的4.0 ~25.6倍.该研究为大量生产紫锥菊药品可提供富含紫锥菊苷等咖啡酸衍生物的高品质生物医学药材.%Objective:To investigate the effect of auxins 2,4-D, IAA, IBA, NAA on induction of adventitious roots as well as that of IBA concentrations on the growth of adventitious roots and the accumulation of caffeic acid derivatives, with test-tube seedling leaves Echinacea pallida as the explant,and cultivate adventitious roots in bioreactors. Result: 1.0 mg·L-1 IBA was found the best for the induction of adventitious roots,with the numer of induced adventitious roots up to 22. 5 in each culture dish. Among different concentrations for suspension cultivation of IBA tested, 1. 0 mg·L-1lBA was found the most suitable for the growth of adventitious roots and the accumulation of caffeic acid derivatives. In a 5 L balloon type bubble bioreactor,8. 98 g·L-1 dry weight was achieved after one month,which was 2. 05 times of 4. 38 g·L-1 dry weight cultivated in a triangular flask. The content of echinacoside cultivated in a bioreactor was 14. 08 mg g -1 DW, which was 2. 4 times of cultivated roots. The contents of chlorogenic acid, chicoric acid and total caffeic acid derivatives were

  10. IAA oxidase activity in relation to adventitious root formation on stem cuttings of some forest tree species. [Salix tetrasperma, Populus Robusta, Hibiscus rosa-sinensis, Eucalyptus citriodora

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, M.P.; Nanda, K.K.

    1981-01-01

    In rooting tests with stem cuttings, IAA oxidase activity was found to be very high in Salix tetrasperma and Populus 'Robusta' both of which rooted profusely, less in Hibiscus rosa-sinensis which rooted but weakly and insignificant in Eucalyptus citriodora, which did not root at all. Proteins extracted from the stem cuttings of E. citriodora inhibited IAA oxidase activity, and also root formation on hypocotyl cuttings of Phaseolus mungo.

  11. 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

  12. Maturation in Corymbia torelliana × C. citriodora Stock Plants: Effects of Pruning Height on Shoot Production, Adventitious Rooting Capacity, Stem Anatomy, and Auxin and Abscisic Acid Concentrations

    Directory of Open Access Journals (Sweden)

    Ivar Wendling

    2015-10-01

    Full Text Available Repeated pruning of stock plants is a common approach to delaying maturation and maintaining the propagation ability of cuttings, but little is known about the hormonal or anatomical basis for this phenomenon. We tested the effect of two different stock-plant pruning heights (15 cm and 30 cm on shoot production, rooting capacity and rooted cutting vigour of six clones of the eucalypt Corymbia torelliana × C. citriodora. We determined whether differences in rooting potential were related to indole-3-acetic (IAA and abscisic acid (ABA concentrations, or the degree of lignification or sclerification, of the cuttings. Maintaining stock plants at 15 cm height sometimes reduced the production of stem cuttings. However, it often increased the ensuing percentage of cuttings that formed roots, with mean rooting across all clones increasing from 30%–53%. Therefore, the number of rooted cuttings produced by short stock plants was similar to, or higher than, the number produced by tall stock plants. Cuttings from shorter stock plants had faster root elongation and occasionally greater root dry mass, shoot dry mass or shoot height than cuttings from tall stock plants. These differences in rooting potential were generally not related to differences in IAA or ABA concentrations of the cuttings or to differences in their stem anatomy. Pruning at the lower height was more effective in maintaining clonal juvenility, supporting previous findings that stock plant maturation is a limiting factor in clonal propagation of Corymbia torelliana × C. citriodora.

  13. Spatial patterns of radial oxygen loss and nitrate net flux along adventitious roots of rice raised in aerated or stagnant solution

    NARCIS (Netherlands)

    Rubinigg, M; Stulen, G; Elzenga, JTM; Colmer, TD

    2002-01-01

    Roots of rice (Oryza sativa L.) grown in stagnant de-oxygenated solution contain a 'tight' barrier to radial oxygen loss (ROL) in basal zones, whereas roots of plants grown in aerated solution do not. It is generally accepted that the barrier to ROL involves anatomical modifications in the apoplast

  14. In vitro antifungal activity of extracts obtained from Hypericum perforatum adventitious roots cultured in a mist bioreactor against planktonic cells and biofilm of Malassezia furfur.

    Science.gov (United States)

    Simonetti, Giovanna; Tocci, Noemi; Valletta, Alessio; Brasili, Elisa; D'Auria, Felicia Diodata; Idoux, Alicia; Pasqua, Gabriella

    2016-01-01

    Xanthone-rich extracts from Hypericum perforatum root cultures grown in a Mist Bioreactor as antifungal agents against Malassezia furfur. Extracts of Hypericum perforatum roots grown in a bioreactor showed activity against planktonic cells and biofilm of Malassezia furfur. Dried biomass, obtained from roots grown under controlled conditions in a ROOTec mist bioreactor, has been extracted with solvents of increasing polarity (i.e. chloroform, ethyl acetate and methanol). The methanolic fraction was the richest in xanthones (2.86 ± 0.43 mg g(-1) DW) as revealed by HPLC. The minimal inhibitory concentration of the methanol extract against M. furfur planktonic cells was 16 μg mL(-1). The inhibition percentage of biofilm formation, at a concentration of 16 μg mL(-1), ranged from 14% to 39%. The results show that H. perforatum root extracts could be used as new antifungal agents in the treatment of Malassezia infections.

  15. Adventitious rooting of auxin-treated Lavandula dentata cuttings Enraizamento adventício de estacas de Lavandula dentata tratadas com auxina

    Directory of Open Access Journals (Sweden)

    Claudine Maria de Bona

    2010-05-01

    Full Text Available Lavandula species may be propagated by seeds. However, plants will present expressive variation both in size and essential oil content. Indole-3-butyric acid (IBA is a growth regulator which efficiently stimulates rooting and the objective of this research was to observe the influence of different IBA concentrations on rooting of L. dentata cuttings. Herbaceous cuttings with approximately 10cm in length and around 1/3 of leaf retention had their bases submerged into 0 (control, 500, 1.000, 2.000 or 3.000mg dm-3 of IBA diluted in de-ionized water for 30 seconds and placed in polystyrene foam trays filled with commercial substrate and kept under intermittent mist system. Averages of root number, length of the longest root, fresh and dry root weight, and percentage of rooted cuttings were evaluated after 60 days. There was no significant difference between treatments for the length of root, fresh and dry root weight. The percentage of rooted cuttings increased with IBA concentrations. A quadratic regression was obtained to root number. The 2.000mg dm-3 dose increased the percentage of rooted cuttings and the mean root number per cutting. L. dentata cuttings are easy to root.Espécies de Lavandula podem ser propagadas por sementes. Entretanto, as plantas apresentarão elevada variabilidade em tamanho e em produção de óleo essencial. O ácido indol-3-butírico (AIB é um regulador de crescimento que eficientemente estimula o enraizamento. O objetivo deste trabalho foi observar a influência de diferentes concentrações de AIB no enraizamento de estacas de L. dentata. Estacas herbáceas com aproximadamente 10cm de comprimento e 1/3 de retenção foliar tiveram suas bases submersas em 0 (controle, 500, 1.000, 2.000 ou 3.000mg dm-3 de AIB diluído em água deionizada por 30 segundos e colocadas em bandejas de isopor contendo substrato comercial sob sistema de nebulização intermitente. As médias de número de raízes, comprimento da raiz mais

  16. 诱导樱桃试管苗生根的研究%Adventitious root induction of cherry(Prunus cerasus × p· avium ) in vitro

    Institute of Scientific and Technical Information of China (English)

    孙清荣; 孙洪雁

    2000-01-01

    Propagation on vitro with cherry(Prunus cerasus × P. avium )hybrid "S2" showed that culture in dark marked ly affected rooting, IBA and sucrose had smaller effect on rooting.%以甜樱桃和酸樱桃杂种"S2"的试管苗为试材,研究了IBA、蔗糖及暗培养时间对不定根产生的影响。结果表明,暗培养对不定根产生有显著影响,IBA和蔗糖的影响作用较小,获得高生根率的最优组合为1/2 MS+IBA 0.1m/gL+蔗糖3%培养基、暗培养7天。

  17. The role of polyamine oxidative degradation in the adventitious rooting of soybean cotyledon node%多胺氧化降解在大豆子叶节分化形成不定根中的作用

    Institute of Scientific and Technical Information of China (English)

    胡文婷; 杨北宁; 苏国兴

    2011-01-01

    以“吉林小粒7号”大豆种子[ Glycine max(L.)Merr.]为材料,研究多胺氧化降解在大豆子叶节分化形成不定根中的作用.结果显示:三种外源多胺(Put,Spd和Spm)都能显著促进大豆子叶节分化形成不定根,而亚精胺合酶抑制剂环已胺(CHA)对大豆子叶节分化出不定根有抑制作用;多胺氧化酶专性抑制剂氨基胍(AG)可显著抑制大豆子叶节分化形成不定根,与此相一致的是,外植体DAO活性和H2O2含量相应降低,内源多胺有一定的积累;H2O2清除剂N,N-二甲基硫脲(DMTU)处理可显著抑制大豆子叶节分化形成不定根,并可降低外源多胺对大豆子叶节分化形成不定根的促进作用.这些结果暗示,大豆子叶节分化出不定根的过程可能与多胺氧化降解有关,并且降解产物H2O2可能参与了此过程.%Soybean[Glycine max(L. ) Merr. ] cv. "Jilin pellets 7" seeds were used to study the role of polyamine oxidative degradation in the rooting of soybean cotyledon node. The results showed that exogenous polyamines ( Put, Spd and Spm) significantly enhanced rooting of soybean cotyledon node, while cyclohexylamine ( CHA, an inhibitor of Spd synthase) inhibited rooting of soybean cotyledon node. Aminoguanidine ( AG, a specific inhibitor of polyamine oxidases) strongly blocked the differentiation of soybean cotyledon node. Meanwhile diamine oxidase (DAO) activities and H2O2 content decreased and endogenous polyamine contents simultaneously accumulated to some extent. N, N-dimethylthiourea (DMTU, a scavenger of H2O2) inhibited rooting of soybean cotyledon node, and could markedly reduce the Pas-promoted effect on rooting of soybean cotyledon node. These results suggest that the differentiation of soybean cotyledon node to form adventitious roots is associated with the oxidative degradation of polyamines, and that their products, especially H2 02, may be involved in this process.

  18. NO和NADPH-黄递酶在绿豆下胚轴不定根发生和发育过程中的变化%Change of Nitric Oxide and NADPH-diaphorase During the Generation and the Development of Adventitious Roots in Mung Bean Hypocotyl Cuttings

    Institute of Scientific and Technical Information of China (English)

    佘小平; 黄爱霞

    2004-01-01

    Effects of nitric oxide (NO) donor sodium nitroprusside (SNP), NO specific scavenger c-PTIO and nitric oxide synthase (NOS) inhibitor L-NAME on the rooting of mung bean ( Vigna radiata L.) hypocotyl cuttings were studied. The spatio-temporal changes of NO and NADPH-diaphorase in the basal part of cutting were also detected during the adventitious rooting process. The results showed that SNP significantly enhanced the adventitious rooting in the range of concentrations tested. NADPH-diaphorase activity (commonly employed as a marker for NOS) and the fluorescence of NO were respectively observed in the zone between the vascular bundles of the basal part of cuttings at 24 h and 36 h after cutting. The root primordium became discernible at 48 h after cutting in the same region, and became more elongate at 60 h. NADPH-diaphorase activity and NO fluorescence gradually increased during 48-60 h and mainly distributed in root meristem. L-NAME treatment delayed adventitious root emergency and significantly reduced the NADPH-diaphorase staining and the fluorescence of NO. The specific NO scavenger, c-PTIO,also suppressed the fluorescence and inhibited the formation of adventitious roots. These results suggest that endogenous NO appears to play a key role in the generation and development of adventitious roots,and the production of NO in this process may be catalyzed by NOS-like enzyme.%研究了一氧化氮(NO)供体普钠(SNP)、一氧化氮清除剂C-PTIO和一氧化氮合酶(NOS)抑制L-NAME对绿豆(Vigna radiataL.)下胚轴插条生根的影响.并对不定根生期间手条基部NO\t和NADPH-黄递酶的时空变化进行了检测.所试浓度SNP均明显促进下胚轴不根发生.分别插条切取后24h和36h于其基部维管束之间检测到NADPH-黄递酶(NOS标记酶)阳性反应和NO荧光,根原基也于48h在相同位置出现,并于60h进一步伸长.48~60h期间,NADPH、黄递的阳性反应及NO荧光有增强趋势,并主要分布在不定根分生组织

  19. Mutation breeding in sweet potato with fast neutrons by inducing hypocotyl adventitious buds

    International Nuclear Information System (INIS)

    Hybrid sweet potato seeds were irradiated by fast neutrons. After the irradiation, adventitious buds were induced from the epidermal cells of the hypocotyls of the seedlings. The adventitious buds appeared from the hypocotyls 2 - 3 cm below the cotyledonary node. Detailed observations of cell division and tissue dissection showed that some adventitious buds emerged in 20 - 45 days after seedling emergence. Most of them originated from a single cell. These adventitious bud clones showed a wide mutation spectrum at high frequency, mostly non-chimeric. The mutant characters included the color of leaf, vine, vein, root-tuber skin and the leaf shape, yield, root-tuber dry matter rates, root-tuber numbers, sprouting, early tuber formation, resistance to black rot, root rot, nematodes etc. The results were confirmed in the field; the observed mutant characters were stable and non-chimeric. Such a method of inducing mutations is advantageous for the improvement of economic characters. Actually, there were examples of increasing the dry matter content of the tubers by 1.0 - 5.5%, the yield of tubers increased by 3.6 - 53.8%, and tubers per plant increased by 0.6 - 4.2%. The resistances to black rot, root rot, nematodes etc. were also improved. Three multiple resistance varieties Yanshu 568, Yanshu 571-1, 84-C-2 and two good quality varieties Yanshu 759 and 781 have been selected. (author). 9 refs, 3 tabs

  20. Cytokinin-induced promotion of root meristem size in the fern Azolla supports a shoot-like origin of euphyllophyte roots

    NARCIS (Netherlands)

    de Vries, Jan; Fischer, Angela Melanie; Roettger, Mayo; Rommel, Sophie; Schluepmann, Henriette; Bräutigam, Andrea; Carlsbecker, Annelie; Gould, Sven Bernhard

    2016-01-01

    The phytohormones cytokinin and auxin orchestrate the root meristem development in angiosperms by determining embryonic bipolarity. Ferns, having the most basal euphyllophyte root, form neither bipolar embryos nor permanent embryonic primary roots but rather an adventitious root system. This raises

  1. Melatonin promotes adventitious root regeneration in in vitro shoot tip explants of the commercial sweet cherry rootstocks CAB-6P (Prunus cerasus L.), Gisela 6 (P. cerasus × P. canescens), and MxM 60 (P. avium × P. mahaleb).

    Science.gov (United States)

    Sarropoulou, Virginia N; Therios, Ioannis N; Dimassi-Theriou, Kortessa N

    2012-01-01

    The objectives of this study were to test the effects of melatonin (N-acetyl-5-methoxytryptamine), a natural compound of edible plants on the rooting of certain commercial sweet cherry rootstocks. Shoot tip explants from previous in vitro cultures of the cherry rootstocks CAB-6P (Prunus cerasus L.), Gisela 6 (P. cerasus × P. canescens), and M × M 60 (P. avium × P. mahaleb) were included in the experiment. The effect of indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) alone or in combination with melatonin was tested concerning their rooting potential. Seven concentrations of melatonin (0, 0.05, 0.1, 0.5, 1, 5, and 10 μM) alone or in combination with 5.71 μM of IAA or 4.92 μM of IBA were tested. For each rootstock, 21 treatments were included. The explants were grown in glass tubes containing 10 mL of substrate. The parameters measured include rooting percentage, number of roots per rooted explant, root length, and callus formation. The data presented in this study show that melatonin has a rooting promoting effect at a low concentration but a growth inhibitory effect at high concentrations. In the absence of auxin, 1 μM melatonin had auxinic response concerning the number and length of roots, but 10 μM melatonin was inhibitory to rooting in all the tested rootstocks. The final conclusion of this experiment is that exogenously applied melatonin acted as a rooting promoter and its action was similar to that of IAA. PMID:21749439

  2. [Research progress of adventitious respiratory sound signal processing].

    Science.gov (United States)

    Li, Zhenzhen; Wu, Xiaoming

    2013-10-01

    Adventitious respiratory sound signal processing has been an important researching topic in the field of computerized respiratory sound analysis system. In recent years, new progress has been achieved in adventitious respiratory sound signal analysis due to the applications of techniques of non-stationary random signal processing. Algorithm progress of adventitious respiratory sound detections is discussed in detail in this paper. Then the state of art of adventitious respiratory sound analysis is reviewed, and development directions of next phase are pointed out.

  3. Adventitious rhizogenesis in Bambusa nutans and Bambusa tulda: Influence of seasonal variation, IBA and cutting type

    Institute of Scientific and Technical Information of China (English)

    S. Singh; S. Yadav; P. K. Patel; S.A.Ansari

    2011-01-01

    The influence of seasonal variation,indole-3-butyric acid (IBA) and type of cuttings wasexamined on induction and growth of adventitious roots in Bambusa nutans Wall.and Bambusa tulda Roxb.Singlenode culm and culm-branch cuttings from the mature culms were provided with immersion treatment for 24 h of either water (control) or 2 mM IBA in four different seasons,i.e.,spring (mid February),summer (mid May),rainy (mid July),and winter (mid November) and maintained for two months in the mist chamber at the relative humidity of (70±5)%and the temperature of (30±2)℃.In B.nutans,adventitious rooting occuffed in both types of cuttings in all the seasons with the best rooting in the summer season i.e.,May (88% in culm cuttings) and the least in winter.On the contrary,adventitious rooting was recorded only in culm cuttings in spring and summer season in B.tulda.IBA treatment significantly enhanced rooting,root number and root length; registering 14 to 17 times improvement over control in the best rooting season.Three factor- interactions (season × cutting type × IBA treatment) were significant for rooting in B.nutans and all characteristics,except sprouting in B.tulda.Thus,single-node culm and culm-branch cuttings in B.nutans and culm cuttings in B.tulda treated with 2 mM IBA during spring (February)to summer (May) season are recommended for their clonal multiplication.

  4. Transport and distribution of basally applied indoleaceticacid-2-/sup 14/C in bean (Phaseolus vulgaris L. ) cuttings in relation to interaction of auxin and indole in adventitious root formation

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh Choudhary, K.; Basu, R.N. (University Coll. of Agriculture, Calcutta (India))

    1981-07-01

    Negative interaction or antagonism between IAA and high concentration of indole in rooting of bean cuttings was associated with significant increase in upward movement and accumulation of radiocarbon of IAA-2-/sup 14/C in upper parts of the cuttings. Positive interaction or synergism observed with lower concentrations of indole was not associated with such increased acropetal transport. There was also no significant difference in total radioactivity per cutting among the different concentrations of indole. The results suggest that non-promotion of upward movement of basally applied auxin from the root forming region or its increased upward movement out of the root forming region may be an important factor in the mechanism of synergism or antagonism respectively.

  5. Adventitious bud regeneration from the stigma of Sinapis alba L.

    Directory of Open Access Journals (Sweden)

    Elżbieta Zenkteler

    2012-12-01

    Full Text Available Stigmas isolated from flower buds of 'Nakielska' variety of Sinapis alba were used to develop a micropropagation method suitable for breeding of new cultivars. The origin of adventitious bud regeneration was studied on MS medium, under stimulation by bezylaminopurine (BAP in combination with 2,4-D - dichlorophenoxyacetic acid (2,4-D. Histological analysis showed the structure of Sinapis stigma (composed from four types of tissue: papillae, transmitting tissue, parenchyma and vascular bundles and revealed that numerous meristematic centers developed from parenchyma cells in close vicinity of vascular bundles. Buds very quickly appeared on the surface of initial explants and later formed multiplantlets that were easily rooted in the soil.

  6. Callus formation impedes adventitious rhizogenesis in air layers of broadleaved tree species

    Directory of Open Access Journals (Sweden)

    Sanjay Singh

    2014-07-01

    Full Text Available Callusing and root induction in air layering was evaluated aiming at evolution of procedure for mass clonal propagation of mature ortets of five tropical broadleaf species differing in their potential for adventitious root formation in shoot cuttings as: Anogiessus latifolia < Boswellia serrata < Dalbergia latifolia < Gmelina arborea < Dalbergia sissoo. Two experiments were conducted in rainy season during consecutive years; without application of growth regulators in the first year and with growth regulators (T1 - water, T2- 100 ppm indole-3-acetic acid, T3-100 ppm thiamine-HCl and T4 -combination of T2 + T3 in the next year. Air layered branches were detached from the trees to record percentage of alive airlayers, callusing and rooting (% as well as root number and root length. Response to air layering was found to be highly variable in five tree species but appeared to be feasible procedure for clonal propagation of mature ortets of B. serrata and D. sissoo with 100% (in auxin + thiamine treatment and 83.3% (in auxin treatment success, respectively. Maximum callusing (% was found in D. latifolia while no callusing was observed in D. sissoo, which is most easy-to-root among all five species. Callus formation impedes adventitious rhizogenesis in air layers as significant negative correlation of callusing (% and adventitious root formation was recorded in air layers of five tropical broadleaved tree species. Application of exogenous auxin alone or in combination with thiamine circumvents callusing to ensure direct development of roots for successful air layering.

  7. A simple method suitable to study de novo root organogenesis

    OpenAIRE

    Xiaodong eChen; Yuliang eQu; Lihong eSheng; Jingchun eLiu; Hai eHuang; Lin eXu

    2014-01-01

    De novo root organogenesis is the process in which adventitious roots regenerate from detached or wounded plant tissues or organs. In tissue culture, appropriate types and concentrations of plant hormones in the medium are critical for inducing adventitious roots. However, in natural conditions, regeneration from detached organs is likely to rely on endogenous hormones. To investigate the actions of endogenous hormones and the molecular mechanisms guiding de novo root organogenesis, we develo...

  8. Development and growth of plantlets of Pinus contorta regenerated from adventitious buds

    Energy Technology Data Exchange (ETDEWEB)

    Flygh, G.; Groenroos, R.; Arnold, S. von [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Genetics; Hoegberg, K.A. [The Association for Forest Tree Breeding, Svaloev (Sweden)

    1998-11-01

    Before micropropagation techniques can be applied to a particular species, it is crucial to optimize the method and to determine how the micropropagated plants grow in the field. Adventitious shoots developed on embryos of Pinus contorta Dougl. ex Loud. after a 2 h pulse treatment with 250 {mu}M N6-benzyladenine. The time to first subculture after the pulse treatment influenced the yield of adventitious shoots. On average, 68% of the adventitious shoots had developed roots 12 weeks after treatment with 1.25 mM indole-3-butyric acid for 6 h. The auxin treatment stimulated early rooting (i.e. within 6 weeks) but had no effect on late rooting (i.e. after 6 weeks). The size of the plantlets was of importance for the survival when potted. All plantlets with a distinct stem elongated during the first growth period while some without did not. The relative height growth rate of plantlets was similar to that of seedlings. In the field the increase of height was similar for plantlets and seedlings. Plagiotropy was higher for the plantlets than for the seedlings (35 and 10% respectively). We concluded that most plantlets of P. contorta elongate normally and have a similar gross morphology to seedlings 23 refs, 8 figs, 4 tabs

  9. 大叶黄杨无芽茎段不定芽再生及其起源%Regenerating and Origin of Adventitious Shoots from Inter-Node Explants of Euonymus japonicus in vitro

    Institute of Scientific and Technical Information of China (English)

    王茂良; 任桂芳; 王建红; 冯慧; 赵梁军

    2005-01-01

    In order to improve the resistance of Euonymus japonicus, its ability of adventitious shoots regenerating from internode stem-segment were researched on MS medium in vitro. The effect of both plant growth regulators and carbon resources in media on adventitious shoots differentiating was studied. Regenerating system of E. japonicus was established successfully.Adventitious shoots were highly obtained from inter-node explants inoculated on MS media supplemented with 6-BA 1.7 mg·L-1+ IBA 0.005 mg·L-1 or 6-BA 1.9 mg·L-1 + IBA 0.03 mg·L-1. The regenerating ratio reached to 52.4% and 46.7% respectively. Media for inducing adventitious roots were I/2MS + IAA 0.5 mg·L-1. Adventitious shoots originated from surface tissue of inter-node stem-segment.

  10. Adventitial vasa vasorum arteriosclerosis in abdominal aortic aneurysm.

    Directory of Open Access Journals (Sweden)

    Hiroki Tanaka

    Full Text Available Abdominal aortic aneurysm (AAA is a common disease among elderly individuals. However, the precise pathophysiology of AAA remains unknown. In AAA, an intraluminal thrombus prevents luminal perfusion of oxygen, allowing only the adventitial vaso vasorum (VV to deliver oxygen and nutrients to the aortic wall. In this study, we examined changes in the adventitial VV wall in AAA to clarify the histopathological mechanisms underlying AAA. We found marked intimal hyperplasia of the adventitial VV in the AAA sac; further, immunohistological studies revealed proliferation of smooth muscle cells, which caused luminal stenosis of the VV. We also found decreased HemeB signals in the aortic wall of the sac as compared with those in the aortic wall of the neck region in AAA. The stenosis of adventitial VV in the AAA sac and the malperfusion of the aortic wall observed in the present study are new aspects of AAA pathology that are expected to enhance our understanding of this disease.

  11. Arabidopsis: an adequate model for dicot root systems?

    OpenAIRE

    Zobel, Richard W.

    2016-01-01

    The Arabidopsis root system is frequently considered to have only three classes of root: primary, lateral, and adventitious. Research with other plant species has suggested up to 8 different developmental/functional classes of root for a given plant root system. If Arabidopsis has only three classes of root, it may not be an adequate model for eudicot plant root systems. Recent research, however, can be interpreted to suggest that pre-flowering Arabidopsis does have at least five (5) of th...

  12. Arabidopsis: An Adequate Model for Dicot Root Systems?

    OpenAIRE

    Zobel, Richard W.

    2016-01-01

    The Arabidopsis root system is frequently considered to have only three classes of root: primary, lateral, and adventitious. Research with other plant species has suggested up to eight different developmental/functional classes of root for a given plant root system. If Arabidopsis has only three classes of root, it may not be an adequate model for eudicot plant root systems. Recent research, however, can be interpreted to suggest that pre-flowering Arabidopsis does have at least five (5) of t...

  13. Review on Mutation in Lateral Root of Rice

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xia; ZHANG Da; HAO Zaibin

    2011-01-01

    Rice roots include seminal roots, adventitious roots, lateral roots and root hairs, At present, progresses in the research of rice roots have been achieved in many aspects, such as root morphology, root activity, root reaction to various environmental factors as a contribution of root growth and rice yield, the relationship between root growth and stems/leaves/flowers/rice, genetic laws of root characters, etc. However, there are very few researches on lateral root mutant. This paper reviewed progresses of the lateral root mutant of rice from the perspectives of phytomorphology to plant physiology and biochemistry to the gene mapping, consisting of mechanism of developing lateral root of rice, gene cloning and functional analysis of lateral root development, the relationship between auxin and lateral roots, agronomic traits of lateral roots mutant, structure and morphology of root hairs, gravity anomaly of root, redox metabolism and proteomics researches of the mutation in lateral root of rice.

  14. Autologous adventitial overlay method reinforces anastomoses in aortic surgery.

    Science.gov (United States)

    Minato, Naoki; Okada, Takayuki; Sumida, Tomohiko; Watanabe, Kenichi; Maruyama, Takahiro; Kusunose, Takashi

    2014-05-01

    In this study, we present an inexpensive and effective method for providing a secure and hemostatic anastomosis using autologous adventitia obtained from a dissected or aneurysmal wall. The resected aortic wall is separated between the adventitia and media, and a soft, 2 × 10-cm adventitial strip is overlaid to cover the anastomotic margin. A graft is sutured to the aortic stump. This autologous adventitial overlay method can inexpensively and strongly reinforce the anastomosis during aortic surgery for dissection or aneurysm and will contribute to anastomotic hemostasis and long-term stability.

  15. Ectopic expression of class 1 KNOX genes induce adventitious shoot regeneration and alter growth and development of tobacco (Nicotiana tabacum L) and European plum (Prunus domestica L).

    Science.gov (United States)

    Srinivasan, C; Liu, Zongrang; Scorza, Ralph

    2011-04-01

    Transgenic plants of tobacco (Nicotiana tabacum L) and European plum (Prunus domestica L) were produced by transforming with the apple class 1 KNOX genes (MdKN1 and MdKN2) or corn KNOX1 gene. Transgenic tobacco plants were regenerated in vitro from transformed leaf discs cultured in a medium lacking cytokinin. Ectopic expression of KNOX genes retarded shoot growth by suppressing elongation of internodes in transgenic tobacco plants. Expression of each of the three KNOX1 genes induced malformation and extensive lobbing in tobacco leaves. In situ regeneration of adventitious shoots was observed from leaves and roots of transgenic tobacco plants expressing each of the three KNOX genes. In vitro culture of leaf explants and internode sections excised from in vitro grown MdKN1 expressing tobacco shoots regenerated adventitious shoots on MS (Murashige and Skoog 1962) basal medium in the absence of exogenous cytokinin. Transgenic plum plants that expressed the MdKN2 or corn KNOX1 gene grew normally but MdKN1 caused a significant reduction in plant height, leaf shape and size and produced malformed curly leaves. A high frequency of adventitious shoot regeneration (96%) was observed in cultures of leaf explants excised from corn KNOX1-expressing transgenic plum shoots. In contrast to KNOX1-expressing tobacco, leaf and internode explants of corn KNOX1-expressing plum required synthetic cytokinin (thidiazuron) in the culture medium to induce adventitious shoot regeneration. The induction of high-frequency regeneration of adventitious shoots in vitro from leaves and stem internodal sections of plum through the ectopic expression of a KNOX1 gene is the first such report for a woody perennial fruit trees.

  16. A simple method suitable to study de novo root organogenesis

    Directory of Open Access Journals (Sweden)

    Xiaodong eChen

    2014-05-01

    Full Text Available De novo root organogenesis is the process in which adventitious roots regenerate from detached or wounded plant tissues or organs. In tissue culture, appropriate types and concentrations of plant hormones in the medium are critical for inducing adventitious roots. However, in natural conditions, regeneration from detached organs is likely to rely on endogenous hormones. To investigate the actions of endogenous hormones and the molecular mechanisms guiding de novo root organogenesis, we developed a simple method to imitate natural conditions for adventitious root formation by culturing Arabidopsis thaliana leaf explants on B5 medium without additive hormones. Here we show that the ability of the leaf explants to regenerate roots depends on the age of the leaf and on certain nutrients in the medium. Based on these observations, we provide examples of how this method can be used in different situations, and how it can be optimized. This simple method could be used to investigate the effects of various physiological and molecular changes on the regeneration of adventitious roots. It is also useful for tracing cell lineage during the regeneration process by differential interference contrast observation of -glucuronidase staining, and by live imaging of proteins labeled with fluorescent tags.

  17. Adventitious shoot formation on leaf cuttings in vivo, a tool in horticulture.

    NARCIS (Netherlands)

    Custers, J.B.M.

    1986-01-01

    Adventitious shoot formation implies the regeneration or development of shoots from fully differentiated tissue. Its application has, after the rise of in vitro culture, assumed large proportions. Then the question arose whether in vivo adventitious shoot formation could not be applied more widely i

  18. Mass culture of mountain Ginseng roots using rare earth elements in bioreactor cultures

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Sung Jin; Kim, Chang Hyun; Kim, Ha Lim [Chonnam National University, Gwangju (Korea, Republic of)

    2010-01-15

    An adventitious roots of mountain ginseng (Panax ginseng C. A. Meyer) was used in this experiments. Various concentration of lanthanide were tested to find out optimal conditions for biomass and ginsenoside contents in mountain ginseng roots. The MS basal medium with 100 {mu}g/L lanthanide created the most optimum condition for growth of adventitious roots of mountain ginseng. Batch culture with 100 {mu}g/L lanthanide and 0.5 g (F.W) inoculation volume produced maximum final biomass of 1.89 g(F.W/flask) within 4 weeks. However, lanthanide was not effect the ginsenoside contents in adventitious roots of mountain ginseng. In bioreactors, 3.23 g F.W./L of biomass were obtained when 100 {mu}g/L lanthanide were added to the MS basal medium at 26 .deg. C

  19. [Induction and in vitro culture of hairy roots of Dianthus caryophyllus and its plant regeneration].

    Science.gov (United States)

    Shi, Heping; Zhu, Yuanfeng; Wang, Bei; Sun, Jiangbing; Huang, Shengqin

    2014-11-01

    To use Agrobacterium rhizogenes-induced hairy roots to create new germplasm of Dianthus caryophyllus, we transformed D. caryophyllus with A. rhizogenes by leaf disc for plant regeneration from hairy roots. The white hairy roots could be induced from the basal surface of leaf explants of D. caryophyllus 12 days after inoculation with A. rhizogenes ATCC15834. The percentage of the rooting leaf explants was about 90% 21 days after inoculation. The hairy roots could grow rapidly and autonomously in liquid or solid phytohormone-free MS medium. The transformation was confirmed by PCR amplification of rol gene of Ri plasmid and silica gel thin-layer chromatography of opines from D. caryophyllus hairy roots. Hairy roots could form light green callus after cultured on MS+6-BA 1.0-3.0 mg/L + NAA 0.1-0.2 mg/L for 15 days. The optimum medium for adventitious shoots formation was MS + 6-BA 2.0 mg/L + NAA 0.02 mg/L, where the rate of adventitious shoot induction was 100% after cultured for 6 weeks. The mean number of adventitious shoot per callus was 30-40. The adventitious shoots can form roots when cultured on phytohormone-free 1/2 MS or 1/2 MS +0.5 mg/L NAA for 10 days. When the rooted plantlets transplanted in the substrate mixed with perlite sand and peat (volume ratio of 1:2), the survival rate was above 95%.

  20. Two SCARECROW-LIKE genes are induced in response to exogenous auxin in rooting-competent cuttings of distantly related forest species.

    Science.gov (United States)

    Sánchez, Conchi; Vielba, Jesús M; Ferro, Enrique; Covelo, Guillermo; Solé, Alicia; Abarca, Dolores; de Mier, Belén S; Díaz-Sala, Carmen

    2007-10-01

    We characterized SCARECROW-LIKE genes induced by auxin in rooting-competent cuttings of two distantly related forest species (Pinus radiata D. Don and Castanea sativa Mill.) before the activation of cell division that results in adventitious root formation. The predicted protein sequences contain domains characteristic of the GRAS protein family and show a strong similarity to the SCARECROW-LIKE proteins, indicating conserved functions of these proteins. Quantitative RT-PCR analysis showed that these genes are expressed at relatively high levels in roots. Induction of increased mRNA levels in rooting-competent cuttings of both species in response to exogenous auxin was observed within the first 24 h of the root induction process, a time when cell reorganization takes place, but before the resumption of cell division and the appearance of adventitious root primordia. These results suggest that SCARECROW-LIKE genes play a role during the earliest stages of adventitious root formation.

  1. Negative phototropism of rice root and its influencing factors

    Institute of Scientific and Technical Information of China (English)

    WANG; Zhong(王忠); MO; Yiwei(莫亿伟); QIAN; Shanqin(钱善勤); GU; Yunjie(顾蕴洁)

    2002-01-01

    Some characteristics of the rice (Oryza sativa L.) root were found in the experiment of unilaterally irradiating the roots which were planted in water: (ⅰ) All the seminal roots, adventitious roots and their branched roots bent away from light, and their curvatures ranged from 25° to 60°. The curvature of adventitious root of the higher node was often larger than that of the lower node, and even larger than that of the seminal root. (ⅱ) The negative phototropic bending of the rice root was mainly due to the larger growth increment of root-tip cells of the irradiated side compared with that of the shaded side. (ⅲ) Root cap was the site of light perception. If root cap was shaded while the root was irradiated the root showed no negative phototropism, and the root lost the characteristic of negative phototropism when root cap was divested. Rice root could resume the characteristic of negative phototropism when the new root cap grew up, if the original cells of root cap were well protected while root cap was divested. (ⅳ) The growth increment and curvature of rice root were both influenced by light intensity. Within the range of 0-100μmol@m-2@s-1, the increasing of light intensity resulted in the decreasing of the growth increment and the increasing of the curvature of rice root. (ⅴ) The growth increment and the curvature reached the maximum at 30℃ with the temperature treatment of 10-40℃. (ⅵ) Blue-violet light could prominently induce the negative phototropism of rice root, while red light had no such effect. (ⅶ) The auxin (IAA) in the solution, as a very prominent influencing factor, inhibited the growth, the negative phototropism and the gravitropism of rice root when the concentration of IAA increased. The response of negative phototropism of rice root disappeared when the concentration of IAA was above 10 mg@L-1.

  2. Adventitious Carbon on Primary Sample Containment Metal Surfaces

    Science.gov (United States)

    Calaway, M. J.; Fries, M. D.

    2015-01-01

    Future missions that return astromaterials with trace carbonaceous signatures will require strict protocols for reducing and controlling terrestrial carbon contamination. Adventitious carbon (AC) on primary sample containers and related hardware is an important source of that contamination. AC is a thin film layer or heterogeneously dispersed carbonaceous material that naturally accrues from the environment on the surface of atmospheric exposed metal parts. To test basic cleaning techniques for AC control, metal surfaces commonly used for flight hardware and curating astromaterials at JSC were cleaned using a basic cleaning protocol and characterized for AC residue. Two electropolished stainless steel 316L (SS- 316L) and two Al 6061 (Al-6061) test coupons (2.5 cm diameter by 0.3 cm thick) were subjected to precision cleaning in the JSC Genesis ISO class 4 cleanroom Precision Cleaning Laboratory. Afterwards, the samples were analyzed by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy.

  3. Adventitious Reinforcement of Maladaptive Stimulus Control Interferes with Learning.

    Science.gov (United States)

    Saunders, Kathryn J; Hine, Kathleen; Hayashi, Yusuke; Williams, Dean C

    2016-09-01

    Persistent error patterns sometimes develop when teaching new discriminations. These patterns can be adventitiously reinforced, especially during long periods of chance-level responding (including baseline). Such behaviors can interfere with learning a new discrimination. They can also disrupt already learned discriminations, if they re-emerge during teaching procedures that generate errors. We present an example of this process. Our goal was to teach a boy with intellectual disabilities to touch one of two shapes on a computer screen (in technical terms, a simple simultaneous discrimination). We used a size-fading procedure. The correct stimulus was at full size, and the incorrect-stimulus size increased in increments of 10 %. Performance was nearly error free up to and including 60 % of full size. In a probe session with the incorrect stimulus at full size, however, accuracy plummeted. Also, a pattern of switching between choices, which apparently had been established in classroom instruction, re-emerged. The switching pattern interfered with already-learned discriminations. Despite having previously mastered a fading step with the incorrect stimulus up to 60 %, we were unable to maintain consistently high accuracy beyond 20 % of full size. We refined the teaching program such that fading was done in smaller steps (5 %), and decisions to "step back" to a smaller incorrect stimulus were made after every 5-instead of 20-trials. Errors were rare, switching behavior stopped, and he mastered the discrimination. This is a practical example of the importance of designing instruction that prevents adventitious reinforcement of maladaptive discriminated response patterns by reducing errors during acquisition. PMID:27622128

  4. Effects of Free-air CO2 Enrichment on Root Characteristics and C:N Ratio of Rice at the Heading Stage

    Institute of Scientific and Technical Information of China (English)

    CHEN Gai-ping; CHENG Lei; ZHU Jian-guo; PANG Jing; XIE Zu-bin; ZENG Qing

    2006-01-01

    A hydroponics experiment was conducted to investigate the rice root growth in FACE (free-air carbon dioxide enrichment). The root biomass, root volume, ratio of root/shoot, number of adventitious roots and root diameter significantly increased under FACE conditions, while the CO2 enrichment decreased the N concentration in rice roots without any change in the C content, leading to an increase in root C:N ratio, Moreover, the elevated CO2 resulted in a remarkable decrease of root activity,expressed as per unit root dry weight, which might be responsible for decreased N concentration in roots.

  5. Adventitious Bursitis Overlying an Osteochondroma of the Humerus Facing the Thoracic Wall

    OpenAIRE

    Zeynep Maras Ozdemır; Mustafa Karakaplan; Aysegul Sagir Kahraman; Nese Karadag

    2013-01-01

    One of the complications of osteochondromas is the development of a bursa over the cartilaginous cap. We report a 15-year-old boy with a rapidly expanded adventitious bursitis overlying an osteochondroma of the humerus facing the thoracic wall, a location not previously reported for such bursa formation. Magnetic resonance imaging readily showed adventitious bursitis overlying the osteochondroma, thereby dispelling concerns for malignant transformation.

  6. Adventitial gene transfer of catalase attenuates angiotensin II-induced vascular remodeling.

    Science.gov (United States)

    Liu, Cun-Fei; Zhang, Jia; Shen, Kai; Gao, Ping-Jin; Wang, Hai-Ya; Jin, Xin; Meng, Chao; Fang, Ning-Yuan

    2015-04-01

    Vascular adventitia and adventitia‑derived reactive oxygen species (ROS) contribute to vascular remodeling following vascular injury. A previous ex vivo study in adventitial fibroblasts showed that catalase, one of most important anti‑oxide enzymes, was downregulated by angiotensin II (AngII). The aim of the present study was to investigate whether adventitial gene transfer of catalase affects AngII‑induced vascular remodeling in vivo. Adenoviruses co‑expressing catalase and enhanced green fluorescent protein (eGFP) or expressing eGFP only were applied to the adventitial surface of common carotid arteries of Sprague‑Dawley rats. Alzet minipumps administering AngII (0.75 mg/kg/day) were then implanted subcutaneously for 14 days. Systolic blood pressure and biological parameters of vascular remodeling were measured in each group. Adventitial fibroblasts were cultured and p38 mitogen‑activated protein kinase (MAPK) phosphorylation was measured using western blot analysis. The results showed that adventitial gene transfer of catalase had no effect on AngII‑induced systolic blood pressure elevation. However, catalase adenovirus transfection significantly inhibited AngII‑induced media hypertrophy compared with that of the control virus (Pcatalase transfection significantly attenuated AngII‑induced ROS generation, macrophage infiltration, collagen deposition and adventitial α‑smooth muscle actin expression. Furthermore, catalase transfection significantly inhibited the AngII‑induced increase in p38MAPK phosphorylation. In conclusion, the results of the present study demonstrated that adventitial gene transfer of catalase significantly attenuated AngII‑induced vascular remodeling in rats via inhibition of adventitial p38MAPK phosphorylation.

  7. Cystic adventitial disease of the popliteal artery: features on 3T cardiovascular magnetic resonance

    Directory of Open Access Journals (Sweden)

    Gelabert Hugh

    2008-08-01

    Full Text Available Abstract Cystic adventitial disease (CAD of the popliteal artery is a rare vascular disease of unknown etiology in which a mucin-containing cyst develops in the adventitial layer of the artery. We report the case of a 26-year-old male with CAD of the right popliteal artery diagnosed non-invasively with 3 Tesla cardiovascular magnetic resonance and confirmed on post-operative histopathology.

  8. Adventitious shoot formation on leaf cuttings in vivo, a tool in horticulture.

    OpenAIRE

    Custers, J.B.M.

    1986-01-01

    Adventitious shoot formation implies the regeneration or development of shoots from fully differentiated tissue. Its application has, after the rise of in vitro culture, assumed large proportions. Then the question arose whether in vivo adventitious shoot formation could not be applied more widely in commercial horticulture. To answer this question investigations were made on the regeneration of leaf cuttings and the results are presented in this thesis.It was found that the majority of a lar...

  9. Cystic adventitial disease of the popliteal artery: features on 3T cardiovascular magnetic resonance

    OpenAIRE

    Gelabert Hugh; Finn J Paul; Lai Chi; Tomasian Anderanik; Krishnam Mayil S

    2008-01-01

    Abstract Cystic adventitial disease (CAD) of the popliteal artery is a rare vascular disease of unknown etiology in which a mucin-containing cyst develops in the adventitial layer of the artery. We report the case of a 26-year-old male with CAD of the right popliteal artery diagnosed non-invasively with 3 Tesla cardiovascular magnetic resonance and confirmed on post-operative histopathology.

  10. Adventitious shoot regeneration of the medicinal aquatic plant water hyssop (Bacopa monnieri L. Pennell using different internodes

    Directory of Open Access Journals (Sweden)

    Karatas M.

    2013-01-01

    Full Text Available Water hyssop (Bacopa monnieri L. is an important medicinal plant due to its active compounds. The plant is also used in ornamental aquaria mainly due to its appearance and adaptability. This study reports on the adventitious shoot regeneration of water hyssop by culturing different internodes and leaf explants on MS media supplemented with various combinations of BA and NAA. All explants induced calli and shoots on all combinations of BA+NAA. The maximum number of shoots per explant on all explants was observed on MS medium supplemented with 0.25 mg/l BA+0.25 mg/l NAA. A higher concentration of NAA inhibited shoot regeneration with all concentrations of BA. Shoots obtained from leaf explants were longer than those from other explants. Regenerated shoots were successfully rooted on MS medium supplemented with IBA. Rooted plantlets were successfully acclimatized in water of various pH levels between 4.0-10.00. It was found that plants can be established on slightly acidic to slightly alkaline media. However, pH 8.0 was found to be more suitable for plant growth under aquatic conditions.

  11. Quantification of Adventitial Vasa Vasorum Vascularization in Double-injury Restenotic Arteries

    Institute of Scientific and Technical Information of China (English)

    Meng Ye; Bai-Gen Zhang; Lan Zhang; Hui Xie; Hao Zhang

    2015-01-01

    Background:Accumulating evidence indicates a potential role of adventitial vasa vasorum (VV) dysfunction in the pathophysiology of restenosis.However,characterization ofVV vascularization in restenotic arteries with primary lesions is still missing.In this study,we quantitatively evaluated the response of adventitial VV to vascular injury resulting from balloon angioplasty in diseased arteries.Methods:Primary atherosclerotic-like lesions were induced by the placement of an absorbable thread surrounding the carotid artery of New Zealand rabbits.Four weeks following double-injury induced that was induced by secondary balloon dilation,three-dimensional patterns of adventitial VV were reconstructed;the number,density,and endothelial surface of VV were quantified using micro-computed tomography.Histology and immunohistochemistry were performed in order to examine the development of intimal hyperplasia.Results:Results from our study suggest that double injured arteries have a greater number of VV,increased luminal surface,and an elevation in the intima/media ratio (I/M),along with an accumulation ofmacrophages and smooth muscle cells in the intima,as compared to sham or single injury arteries.I/M and the number of VV were positively correlated (R2 =0.82,P < 0.001).Conclusions:Extensive adventitial VV neovascularization occurs in injured arteries after balloon angioplasty,which is associated with intimal hyperplasia.Quantitative assessment of adventitial VV response may provide insight into the basic biological process of postangioplasty restenosis.

  12. Comparison between Adventitial and Intimal Inflammation of Ruptured and Nonruptured Atherosclerotic Plaques in Human Coronary Arteries

    Directory of Open Access Journals (Sweden)

    Higuchi Maria L.

    2002-01-01

    Full Text Available OBJECTIVE: To verify the possible role of adventitial inflammation in atherosclerotic plaque vulnerability and coronary artery remodelling. METHODS: We compared the mean numbers of lymphocytes in the adventitia and in the plaque of ruptured thrombosed and stable equi-stenotic coronary segments of 34 patients who died due to acute myocardial infarction. We also analysed adventitial microvessels, adventitial fibrosis and the external elastic membrane. RESULTS: In the adventitia, the numbers of lymphocytes and microvessels/mm² were 69.5±88.3 and 60.9± 32.1 in culprit lesions and 16.4 ± 21.1 and 44.3±16.1 in stable lesions (p<0.05; within the plaques, the mean number of lymphocytes was 24±40.8 in culprit lesions and 10.9±13.2 in stable ones (p=0.17. The mean percent area of adventitial fibrosis/cross-sectional area of the vessel was significantly lower in unstable plaques (p<0.001. The confocal images showed holes in the external elastic membrane. CONCLUSION: Unstable plaques exhibit chronic pan-arteritis, accompanied by enlargement, medial thinning, and less fibrosis than in stable lesions, which is compatible with vessel aneurysm. Adventitial inflammation may contribute significantly to atheroma instability.

  13. Aerenchyma and an Inducible Barrier to Radial Oxygen Loss Facilitate Root Aeration in Upland, Paddy and Deep‐water Rice (Oryza sativa L.)

    OpenAIRE

    COLMER, T. D.

    2003-01-01

    The present study evaluated waterlogging tolerance, root porosity and radial O2 loss (ROL) from the adventitious roots, of seven upland, three paddy, and two deep‐water genotypes of rice (Oryza sativa L.). Upland types, with the exception of one genotype, were as tolerant of 30 d soil waterlogging as the paddy and deep‐water types. In all but one of the 12 genotypes, the number of adventitious roots per stem increased for plants grown in waterlogged, compared with drained, soil. When grown in...

  14. Development of a candidate reference material for adventitious virus detection in vaccine and biologicals manufacturing by deep sequencing

    OpenAIRE

    Edward T Mee; Preston, Mark D.; Minor, Philip D.; ,; Huang, Xuening; Nguyen, Jenny; Wall, David; Hargrove, Stacey; Fu, Thomas; Xu, George; Li, Li; Cote, Colette; Delwart, Eric; Li, Linlin; Hewlett, Indira

    2016-01-01

    Background Unbiased deep sequencing offers the potential for improved adventitious virus screening in vaccines and biotherapeutics. Successful implementation of such assays will require appropriate control materials to confirm assay performance and sensitivity. Methods A common reference material containing 25 target viruses was produced and 16 laboratories were invited to process it using their preferred adventitious virus detection assay. Results Fifteen laboratories returned results, obtai...

  15. Adventitial cystic disease of the left external iliac vein: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Sang Hee; Shin, Hyun Woong; Lee, Yil Gi; Koo, Mi Jin [Daegu Fatima Hospital, Daegu (Korea, Republic of)

    2005-10-15

    Adventitial cystic disease (ACD) is a rare, but well-characterized vascular disease. It is most commonly seen in the popliteal artery, but it has also been reported in the venous system. The most commonly involved segment has been the common femoral vein; the disease resulted in luminal compromise and extremity swelling. We report here on a case of adventitial cystic disease of the left external iliac vein that was initially misdiagnosed as deep vein thrombosis in a 68-years-old man who presented with a painless swelling of his left leg.

  16. Aerenchyma and an inducible barrier to radial oxygen loss facilitate root aeration in upland, paddy and deep-water rice (Oryza sativa L.).

    Science.gov (United States)

    Colmer, T D

    2003-01-01

    The present study evaluated waterlogging tolerance, root porosity and radial O(2) loss (ROL) from the adventitious roots, of seven upland, three paddy, and two deep-water genotypes of rice (Oryza sativa L.). Upland types, with the exception of one genotype, were as tolerant of 30 d soil waterlogging as the paddy and deep-water types. In all but one of the 12 genotypes, the number of adventitious roots per stem increased for plants grown in waterlogged, compared with drained, soil. When grown in stagnant deoxygenated nutrient solution, genotypic variation was evident for root porosity and rates of ROL, but there was no overall difference between plants from the three cultural types. Adventitious root porosity increased from 20-26 % for plants grown in aerated solution to 29-41 % for plants grown in stagnant solution. Growth in stagnant solution also induced a 'tight' barrier to ROL in the basal regions of adventitious roots of five of the seven upland types, all three paddy types, and the two deep-water types. The enhanced porosity provided a low resistance pathway for O(2) movement to the root tip, and the barrier to ROL in basal zones would have further enhanced longitudinal O(2) diffusion towards the apex, by diminishing losses to the rhizosphere. The plasticity in root physiology, as described above, presumably contributes to the ability of rice to grow in diverse environments that differ markedly in soil waterlogging, such as drained upland soils as well as waterlogged paddy fields. PMID:12509350

  17. Cytokinin-induced promotion of root meristem size in the fern Azolla supports a shoot-like origin of euphyllophyte roots.

    Science.gov (United States)

    de Vries, Jan; Fischer, Angela Melanie; Roettger, Mayo; Rommel, Sophie; Schluepmann, Henriette; Bräutigam, Andrea; Carlsbecker, Annelie; Gould, Sven Bernhard

    2016-01-01

    The phytohormones cytokinin and auxin orchestrate the root meristem development in angiosperms by determining embryonic bipolarity. Ferns, having the most basal euphyllophyte root, form neither bipolar embryos nor permanent embryonic primary roots but rather an adventitious root system. This raises the questions of how auxin and cytokinin govern fern root system architecture and whether this can tell us something about the origin of that root. Using Azolla filiculoides, we characterized the influence of IAA and zeatin on adventitious fern root meristems and vasculature by Nomarski microscopy. Simultaneously, RNAseq analyses, yielding 36,091 contigs, were used to uncover how the phytohormones affect root tip gene expression. We show that auxin restricts Azolla root meristem development, while cytokinin promotes it; it is the opposite effect of what is observed in Arabidopsis. Global gene expression profiling uncovered 145 genes significantly regulated by cytokinin or auxin, including cell wall modulators, cell division regulators and lateral root formation coordinators. Our data illuminate both evolution and development of fern roots. Promotion of meristem size through cytokinin supports the idea that root meristems of euphyllophytes evolved from shoot meristems. The foundation of these roots was laid in a postembryonically branching shoot system. PMID:26358624

  18. Integration of root phenes for soil resource acquisition

    Directory of Open Access Journals (Sweden)

    Larry Matthew York

    2013-09-01

    Full Text Available Suboptimal availability of water and nutrients is a primary limitation to plant growth in terrestrial ecosystems. The acquisition of soil resources by plant roots is therefore an important component of plant fitness and agricultural productivity. Plant root systems comprise a set of phenes, or traits, that interact. Phenes are the units of the plant phenotype, and phene states represent the variation in form and function a particular phene may take. Root phenes can be classified as affecting resource acquisition or utilization, influencing acquisition through exploration or exploitation, and in being metabolically influential or neutral. These classifications determine how one phene will interact with another phene, whether through foraging mechanisms or metabolic economics. Phenes that influence one another through foraging mechanisms are likely to operate within a phene module, a group of interacting phenes, that may be co-selected. Examples of root phene interactions discussed are: 1 root hair length × root hair density, 2 lateral branching × root cortical aerenchyma, 3 adventitious root number × adventitious root respiration and basal root growth angle, 4 nodal root number × root cortical aerenchyma, and 5 basal root growth angle × root hair length and density. Progress in the study of phenes and phene interactions will be facilitated by employing simulation modeling and near-isophenic lines that allow the study of specific phenes and phene combinations within a common phenotypic background. Developing a robust understanding of the phenome at the organismal level will require new lines of inquiry into how phenotypic integration influences plant function in diverse environments. A better understanding of how root phenes interact to affect soil resource acquisition will be an important tool in the breeding of crops with superior stress tolerance and reduced dependence on intensive use of inputs.

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

    OpenAIRE

    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 effe...

  20. Tissue sealing device associated thermal spread: a comparison of histologic methods for detecting adventitial collagen denaturation

    Science.gov (United States)

    Jones, Ryan M.; Grisez, Brian T.; Thomas, Aaron C.; Livengood, Ryan H.; Coad, James E.

    2013-02-01

    Thermal spread (thermal tissue damage) results from heat conduction through the tissues immediately adjacent to a hyperthermic tissue sealing device. The extent of such heat conduction can be assessed by the detection of adventitial collagen denaturation. Several histologic methods have been reported to measure adventitial collagen denaturation as a marker of thermal spread. This study compared hematoxylin and eosin staining, Gomori trichrome staining and loss of collagen birefringence for the detection of collagen denaturation. Twenty-eight ex vivo porcine carotid arteries were sealed with a commercially available, FDA-approved tissue sealing device. Following formalin fixation and paraffin embedding, two 5-micron tissue sections were hematoxylin and eosin and Gomori trichrome stained. The hematoxylin and eosin-stained section was evaluated by routine bright field microscopy and under polarized light. The trichromestained section was evaluated by routine bright field microscopy. Radial and midline adventitial collagen denaturation measurements were made for both the top and bottom jaw sides of each seal. The adventitial collagen denaturation lengths were determined using these three methods and statistically compared. The results showed that thermal spread, as represented by histologically detected collagen denaturation, is technique dependent. In this study, the trichrome staining method detected significantly less thermal spread than the hematoxylin and eosin staining and birefringence methods. Of the three methods, hematoxylin and eosin staining provided the most representative results for true thermal spread along the adjacent artery.

  1. Context-Dependent Development of Lymphoid Stroma from Adult CD34+ Adventitial Progenitors

    DEFF Research Database (Denmark)

    Sitnik, Katarzyna Maria; Wendland, Kerstin; Weishaupt, Holger;

    2016-01-01

    ) and thymus that is located within the vascular niche surrounding PDPN-PDGFRβ+/α-Esam-1+ITGA7+ pericytes. CD34+ adventitial cells developed in late embryonic thymus and in postnatal LNs and in the thymus originated, along with pericytes, from a common anlage-seeding progenitor population. Using lymphoid organ...

  2. Effects of 6-BA and MET on the induction of adventitious buds from rice seedlings and its application

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Different levels of 6-BA (6-Benezyla-mino purine) and MET (Paclobutra-zol) were added into MS media to culture the mature seeds of six varieties and two F2 populations of Nanjing11 ( indica ) / Balilla (japoni-ca) and Dular( indica)/Balilla( japonica) . Results were as follows:1) 6-BA was effective in inducing the formation of adventitious buds (Table 1).Only using MET could not induce adventitious buds formation. Compared with the use of 6-BA only, it was more useful for inducing the adventitious buds by using MET and 6-BA together, especially for japonica rice.

  3. Investigations on the cytotoxic influence of zinc on Allium cepa L. roots

    OpenAIRE

    Halina Kocik; Barbara Wojciechowska; Alicja Liguzińska

    2014-01-01

    The influence of various (0.1, 0.08, 0.04, 0.02, 0.01, 0.005, 0.0025 and 0.00125 M) zinc chloride and zinc acetate concentrations on the mitotic activity of the apical meristem of onion adventitious roots was investigated after 24 h of incubation. It was found that the tested compounds have a mitodepressive action and distinctly inhibit root elongation. The results of topochemical analysis are reported.

  4. Hydrogen Sulfide Promotes Root Organogenesis in Ipomoea batatas, Salix matsudana and Glycine max

    Institute of Scientific and Technical Information of China (English)

    Hua Zhang; Jun Tang; Xiao-Ping Liu; Yun Wang; Wei Yu; Wei-Yan Peng; Fang Fang; Dai-Fu Ma; Zhao-Jun Wei; Lan-Ying Hu

    2009-01-01

    In this report, we demonstrate that sodium hydrosulfide (NaHS), a hydrogen sulfide (H2S) donor, promoted adventitious root formation mediated by auxin and nitric oxide (NO). Application of the H2S donor to seedling cuttings of sweet potato (Ipomoea batatas L.) promoted the number and length of adventltious roots in a dose-dependent manner. It was also verified that H2S or HS- rather than other sulfur-containing components derived from NariS could be attributed to the stimulation of adventitious root formation. A rapid Increase In endogenous H2S, indole acetic acid (IAA) and NO were sequentially observed in shoot tips of sweet potato seedlings treated with HallS. Further investigation showed that HzS-mediated root formation was alleviated by N-l-naphthylphthalamic acid (NPA), an IAA transport inhibitor, and 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), an NO scavenger. Similar phenomena in H2S donor-dependent root organogenesis were observed in both excised willow (Sallx matsudana var. tortuosa Vilm) shoots and soybean (Glycine max L.) seedlings. These results indicated that the process of H2S-induced adventitious root formation was likely mediated by IAA and NO, and that H2S acts upstream of IAA and NO signal transduction pathways.

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

    International Nuclear Information System (INIS)

    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)

  6. 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.

  7. 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

  8. 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

  9. Doppler ultrasonography and exercise testing in diagnosing a popliteal artery adventitial cyst.

    Science.gov (United States)

    Taurino, Maurizio; Rizzo, Luigi; Stella, Nazzareno; Mastroddi, Massimo; Conteduca, Fabio; Maggiore, Claudia; Faraglia, Vittorio

    2009-01-01

    We describe popliteal arterial adventitial cystic disease which causes intermittent claudication in a young athletic man, with atypical manifestation, without loss of foot pulses on knee flexion nor murmur in the popliteal fossa. The findings obtained from Magnetic Resonance Imaging were non-diagnostic. The diagnosis resulted from Echo-Doppler ultrasonography along with peak exercise testing. Ultrasonography also provided useful physiopathological informations suggesting that a popliteal artery adventitial cyst can become symptomatic if muscle exertion increases fluid pressure within the cyst, enough to cause hemodynamically significant endoluminal stenosis. Rapid diagnosis is essential to prevent progressive claudication threatening limb viability. To guarantee this professional sportsman a reliable and durable outcome, instead of less aggressive management, we resected the involved arterial segment and interposed an autologous saphenous-vein graft. PMID:19473494

  10. Influences of polar auxin transport on polarity of adventitious bud formation in hybrid populas

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myung Won (Yonsei Univ. Kangwondo (Korea)); Hackett, W. (Univ of Minnesota, St. Paul (USA))

    1989-04-01

    The role of auxin and cytokinin distribution of polar regeneration of adventitious bud has been investigated. Explants from leaf midvein were labelled with {sup 14}C-NAA and {sup 14}C-BA and the radioactivity in proximal, mid, and distal portions was counted after 24h and 48h. Explants showing polar regeneration of buds on the proximal end showed a clear polar distribution of {sup 14}CNAA. Auxin transport inhibitors (NPA, TIBA) eliminated polar distribution of auxin and reduced polarity of bud formation and the total number of buds formed, but did not reduce callus formation. Increased concentration of Ca(NO{sub 3}){sub 2} decreased polarity of bud formation and increased the number of buds formed but did not affect the distribution of auxin of cytokinin. Some factor in addition to polar distribution of auxin or cytokinin-auxin ratio appears to influence the polarity of adventitious bud formation.

  11. [Hair roots induction and culture of Withania somnifera and its withanolide A synthesis].

    Science.gov (United States)

    Wang, Feng-Ying; Sun, Yi-Ming; Lv, Cui-Ping; Cheng, Meng-Qi; Zhang, Lai; Sun, Min

    2014-03-01

    Withanolide A is a biologically active secondary metabolite occuring in roots and leaves of Withania somnifera. In the present study, adventitious roots from leaf explants of W. somnifera were induced for the production of withanolide-A by Agrobacterium tumefaciens strain C58C1 to obtain hair roots. Hair roots induction rate reached 30%. The withanolide A was determined by HPLC in different hair roots lines and different parts of W. somnifera. The average content of withanolide A in all hair roots lines were 1.96 times as high as that in wild-plant, the concentration of withanolide A in hair roots (1.783 mg x g(-1) dry weight) were 1.51 times as high as the roots of wild W. somnifera (1.180 mg x g(-1) dry weight), respectively. It is possible to obtain withanolide A from hair roots culture of W. somnifera.

  12. Context-Dependent Development of Lymphoid Stroma from Adult CD34+ Adventitial Progenitors

    Directory of Open Access Journals (Sweden)

    Katarzyna M. Sitnik

    2016-03-01

    Full Text Available Despite the key role of primary and secondary lymphoid organ stroma in immunity, our understanding of the heterogeneity and ontogeny of these cells remains limited. Here, we identify a functionally distinct subset of BP3−PDPN+PDGFRβ+/α+CD34+ stromal adventitial cells in both lymph nodes (LNs and thymus that is located within the vascular niche surrounding PDPN−PDGFRβ+/α−Esam-1+ITGA7+ pericytes. CD34+ adventitial cells developed in late embryonic thymus and in postnatal LNs and in the thymus originated, along with pericytes, from a common anlage-seeding progenitor population. Using lymphoid organ re-aggregate grafts, we demonstrate that adult CD34+ adventitial cells are capable of differentiating into multiple lymphoid stroma-like subsets including pericyte-, FRC-, MRC-, and FDC-like cells, the development of which was lymphoid environment-dependent. These findings extend the current understanding of lymphoid mesenchymal cell heterogeneity and highlight a role of the CD34+ adventitia as a potential ubiquitous source of lymphoid stromal precursors in postnatal tissues.

  13. Dynamic transcriptional profiling provides insights into tuberous root development in Rehmannia glutinosa

    Directory of Open Access Journals (Sweden)

    Peng eSun

    2015-06-01

    Full Text Available Rehmannia glutinosa, a herb of the Scrophulariaceae family, is widely cultivated in the Northern part of China. The tuberous root has well known medicinal properties; however, yield and quality are threatened by abiotic and biotic stresses. Understanding the molecular process of tuberous root development may help identify novel targets for its control. In the present study, we used Illumina sequencing and de novo assembly strategies to obtain a reference transcriptome that is relevant to tuberous root development. We then conducted RNA-seq quantification analysis to determine gene expression profiles of the adventitious root (AR, thickening adventitious root (TAR, and the developing tuberous root (DTR. Expression profiling identified a total of 6,974 differentially expressed unigenes during root developmental. Bioinformatics analysis and gene expression profiling revealed changes in phenylpropanoid biosynthesis, starch and sucrose metabolism, and plant hormone biosynthesis during root development. Moreover, we identified and allocated putative functions to the genes involved in tuberous root development, including genes related to major carbohydrate metabolism, hormone metabolism, and transcription regulation. The present study provides the initial description of gene expression profiles of AR, TAR, and DTR, which facilitates identification of genes of interest. Moreover, our work provides insights into the molecular mechanisms underlying tuberous root development and may assist in the design and development of improved breeding schemes for different R. glutinosa varieties through genetic manipulation.

  14. An auxin-responsive endogenous peptide regulates root development in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Fengxi Yang; Yu Song; Hao Yang; Zhibin Liu; Genfa Zhu; Yi Yang

    2014-01-01

    Auxin plays critical roles in root formation and development. The components involved in this process, however, are not well understood. Here, we newly identified a peptide encoding gene, auxin-responsive endogenous polypeptide 1 (AREP1), which is induced by auxin, and mediates root development in Arabidopsis. Expression of AREP1 was specific to the cotyledon and to root and shoot meristem tissues. Amounts of AREP1 transcripts and AREP1-green fluorescent protein fusion proteins were elevated in response to indoleacetic acid treatment. Suppression of AREP1 through RNAi silencing resulted in reduction of primary root length, increase of lateral root number, and expansion of adventitious roots, compared to the observations in wild-type plants in the presence of auxin. By contrast, transgenic plants overexpressing AREP1 showed enhanced growth of the primary root under auxin treatment. Additionally, rootmorphology, including lateral root number and adventitious roots, differed greatly between transgenic and wildtype plants. Further analysis indicated that the expression of auxin-responsive genes, such as IAA3, IAA7, IAA17, GH3.2, GH3.3, and SAUR-AC1, was significantly higher in AREP1 RNAi plants, and was slightly lower in AREP1 overexpressing plants than in wildtype plants. These results suggest that the novel endogenous peptide AREP1 plays an important role in the process of auxinmediated root development.

  15. Effect of Indoleacetic acid (IAA) on the Negative Phototropism of Rice Root

    Institute of Scientific and Technical Information of China (English)

    MoYi-wei; WANGZhong; QIANShan-qin; GuYun-jie

    2004-01-01

    To explore the effects of IAA on negative phototropism of rice (Oryza sativa L) root, agar block containing IAA was unilaterally applied on root tip to examine the phototropic response of root to exogenous IAA, and microstructure of the bending part was observed with an optical microscope. The growth of seminal roots could be regulated by exogenous IAA as well as light,as a result the root bent towards the site treated, causing asymmetric growth of the root cells at the elongation zone and consequently bending growth. IAA concentration in the shaded side of adventitious root increased much greater at 1.5 h after the start of irradiation. The unequal lateral IAA distribution can be concluded to be the main cause for negative phototropism of rice root.

  16. Effect of Indoleacetic acid (IAA) on the Negative Phototropism of Rice Root

    Institute of Scientific and Technical Information of China (English)

    Mo Yi-wei; WANG Zhong; QIAN Shan-qin; GU Yun-jie

    2004-01-01

    To explore the effects of IAA on negative phototropism of rice ( Oryza sativa L.) root, agar block containing IAA was unilaterally applied on root tip to examine the phototropic response of root to exogenous IAA, and microstructure of the bending part was observed with an optical microscope. The growth of seminal roots could be regulated by exogenous IAA as well as light,as a result the root bent towards the site treated, causing asymmetric growth of the root cells at the elongation zone and consequently bending growth. IAA concentration in the shaded side of adventitious root increased much greater at 1.5 h after the start of irradiation. The unequal lateral IAA distribution can be concluded to be the main cause for negative phototropism of rice root.

  17. Auxins differentially regulate root system architecture and cell cycle protein levels in maize seedlings.

    Science.gov (United States)

    Martínez-de la Cruz, Enrique; García-Ramírez, Elpidio; Vázquez-Ramos, Jorge M; Reyes de la Cruz, Homero; López-Bucio, José

    2015-03-15

    Maize (Zea mays) root system architecture has a complex organization, with adventitious and lateral roots determining its overall absorptive capacity. To generate basic information about the earlier stages of root development, we compared the post-embryonic growth of maize seedlings germinated in water-embedded cotton beds with that of plants obtained from embryonic axes cultivated in liquid medium. In addition, the effect of four different auxins, namely indole-3-acetic acid (IAA), 1-naphthaleneacetic acid (NAA), indole-3-butyric acid (IBA) and 2,4-dichlorophenoxyacetic acid (2,4-D) on root architecture and levels of the heat shock protein HSP101 and the cell cycle proteins CKS1, CYCA1 and CDKA1 were analyzed. Our data show that during the first days after germination, maize seedlings develop several root types with a simultaneous and/or continuous growth. The post-embryonic root development started with the formation of the primary root (PR) and seminal scutellar roots (SSR) and then continued with the formation of adventitious crown roots (CR), brace roots (BR) and lateral roots (LR). Auxins affected root architecture in a dose-response fashion; whereas NAA and IBA mostly stimulated crown root formation, 2,4-D showed a strong repressing effect on growth. The levels of HSP101, CKS1, CYCA1 and CDKA in root and leaf tissues were differentially affected by auxins and interestingly, HSP101 registered an auxin-inducible and root specific expression pattern. Taken together, our results show the timing of early branching patterns of maize and indicate that auxins regulate root development likely through modulation of the HSP101 and cell cycle proteins. PMID:25615607

  18. Roots Revisited.

    Science.gov (United States)

    Hughes, Barnabas

    1998-01-01

    Offers historical information about square roots. Presents three different methods--Hero's method, visual method, and remainder method--which can be used to teach the finding of square roots and one method for determining cube roots. (ASK)

  19. Adventitious match probability for autosomal profiles when primer binding site mutation is possible.

    Science.gov (United States)

    Pope, Susan; Evett, Ian; Puch-Solis, Roberto

    2016-09-01

    This paper considers the situation where two DNA systems with differing primers have been used to produce DNA profiles for loading and searching of a DNA Database. With any profiling system there exists the possibility of a "primer binding site mutation" (PBSM). When such a mutation occurs at one of the loci in a profile, it has the effect that the associated allele is not visible in the profile. In the case where a person has two different alleles at a given locus (heterozygous) the effect of a PBSM would be that the profile would appear to be that of an individual with only one allele at that locus (homozygous). The paper investigates the potential for an adventitious match as a result of a PBSM when, for example, a crime profile and person profile that have originated from two different individuals are found to be the same as a result of a PBSM in one of the profiles. It is demonstrated, both by theory and using simulations, that the effect of PBSMs is to slightly decrease the adventitious match probability from what it would had the same DNA system been used. PMID:27420391

  20. Salinity-induced reduction in root surface area and changes in major root and shoot traits at the phytomer level in wheat.

    Science.gov (United States)

    Robin, Arif Hasan Khan; Matthew, Cory; Uddin, Md Jasim; Bayazid, Khandaker Nafiz

    2016-06-01

    The aim of this study was to investigate the effect of salinity stress on root growth at the phytomer level in wheat to provide novel site-specific understanding of salinity damage in roots. Seedlings of 13 wheat varieties were grown hydroponically. Plants were exposed to three concentrations of NaCl, 0 (control), 50 and 100mM, from 47 days after sowing. In a destructive harvest 12 days later we determined the number of live leaves, adventitious roots, seminal roots and newly formed roots at the youngest phytomer; length and diameter of main axes; and length and diameter of root hairs and their number per millimetre of root axis. Elongation rate of main axes and root hair density were then derived. Root surface area at each root-bearing phytomer (Pr) was mechanistically modelled. New root formation was increased by salt exposure, while number of live leaves per plant decreased. The greatest salinity effect on root axis elongation was observed at the youngest roots at Pr1 and Pr2. Both the 50mM and the 100mM levels of salinity reduced root hair length by approximately 25% and root hair density by 40% compared with the control whereas root hairs alone contributed around 93% of the estimated total root surface area of an individual tiller. Decrease in main axis length of new roots, root hair density and root hair length combined to reduce estimated root surface area by 36-66% at the higher NaCl concentration. The varietal response towards the three salinity levels was found to be trait-specific. The data highlight reduction in root surface area as a major but previously largely unrecognized component of salinity damage. Salinity resistance is trait-specific. Selection for retention of root surface area at a specific phytomer position following salt exposure might be useful in development of salinity-tolerant crop varieties. PMID:26951370

  1. Advances in experimental methods for root system architecture and root development

    Institute of Scientific and Technical Information of China (English)

    Jun-bang Wang; Xiu-juan Zhang; Chu Wu

    2015-01-01

    Plant roots play important roles in acquisition of water and nutrients, storage, anchoring, transport, and symbiosis with soil microorganisms, thus quantitative researches on root developmental processes are essential to understand root functions and root turnover in ecosystems, and at the same time such researches are the most difficult because roots are hidden underground. Therefore, how to investigate efficiently root functions and root dynamics is the core aspect in underground ecology. In this article, we reviewed some experimental methods used in root resear-ches on root development and root system architecture, and summarized the advantages and shortages of these meth-ods. Based on the analyses, we proposed three new ways to more understand root processes: (1) new experimental materials for root development; (2) a new observatory system comprised of multiple components, including many observatory windows installed in field, analysis software, and automatic data transport devices; (3) new techniques used to analyze quantitatively functional roots.

  2. Apelin-13 attenuates pressure overload-induced aortic adventitial remodeling and fibrosis in Sprague-Dawley rats

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhen-zhou; ZHANG Yan; XU Ran; CHEN Lai-jiang; GUO Shu-jie; XU Ying-le; CHANG Qing; GAO Ping-jin; ZHONG Jiu-chang

    2016-01-01

    AIM:To investigate regulatory roles of Apelin in adventitial remodeling and fibrosis in rats with transverse aortic constriction ( TAC) .METHODS:The male Sprague-Dawley rats with TAC were randomized to daily deliver either pyroglutamyl Apelin-13 ( 50μg/kg) or saline for 4 weeks.RESULTS:Histomorphometric analysis by HE and Masson Trichrome staining revealed increased medi -al and adventitial thicknesses , especially in the adventitia , in ascending aortas in rats with TAC when compared with the sham-operated rats.Downregulation of APJ receptor and elevations in phosphorylated mTOR and ERK 1/2 levels were observed in rats with TAC . There are marked increases in heart weight ( HW) , HW/body weight ratio , and aortic fibrosis in rats with TAC .The pressure over-load-mediated pathological adventitial remodeling was strikingly rescued by Apelin-13, associated with attenuation of aortic fibrosis and reduced mRNA expression of TGF-β1, fibronectin and collagen I .CONCLUSION:Our results demonstrate the importance of Apelin-13 in amelioration of aortic adventitial remodeling and fibrosis in rats with TAC via modulation of the mTOR /ERK signaling , thus indi-cating potential therapeutic strategies by enhancing Apelin /APJ action for preventing pressure overload-and fibrosis-associated cardio-vascular disorders .

  3. Biochemical investigations during in vitro adventitious shoot regeneration in leaflet explants from nodal segments of a mature Albizia procera tree

    Institute of Scientific and Technical Information of China (English)

    Ekta Rai; Sulochna Bouddha; Shamim Akhtar Ansari

    2016-01-01

    The in vitro adventitious shoot differentiation in leaflet explants of an adult tree differed from that of leaflet explants of seedlings of Albizia procera (Roxb.) Benth. reported previously elsewhere. The leaflet explants from an adult tree passed through an initial callus phase for 30 days on MS medium supplemented with 3% sucrose, 2.5 lM 2,4-D followed by a subsequent adventitious shoot differentiation phase for another 30 days on half MS medium supplemented with 0.25 lM each of BA and IBA. The regeneration rate of in vitro adventitious shoots in explants from the adult tree, i.e.1.66 shoots/callus, was lower than that from seedlings, i.e. [10 shoots/callus, which was reported elsewhere. Correspondingly, the activities of nitrate reductase and peroxidase, and endogenous phenol content remained very low during in vitro adventitious shoot differentiation in leaflet explants of an adult tree possibly due to lower availability of competent stem (juvenile) cells for the process.

  4. Potential Role of Axonal Chemorepellent Slit2 in Modulating Adventitial Inflammation in a Rat Carotid Artery Balloon Injury Model.

    Science.gov (United States)

    Liu, Dong; Xiao, Yan; Subramanian, Romesh R; Okamoto, Ei-Ichi; Wilcox, Josiah N; Anderson, Leonard; De Leon, Hector

    2016-05-01

    Leukocyte infiltration of adventitial and perivascular tissues is an early event in the development of vascular remodeling after injury. We investigated whether Slit/Robo-an axonal chemorepellent system in vertebrate and invertebrate development-is activated during the inflammatory phase that follows endothelial denudation. Using the rat carotid artery model of angioplasty, we conducted a time course analysis of mRNAs encoding Slit ligands (Slit2 and Slit3) and Robo receptors (Robo1, Robo2, and Robo4), as well as proinflammatory cell adhesion molecule (CAM) genes. Adventitial inflammatory cells were counted in immunostained arterial sections. E-selectin, vascular CAM-1, and intercellular CAM-1 were upregulated 2-3 hours after injury, followed by infiltration of neutrophils and monocytes as evidenced by real-time polymerase chain reaction, in situ hybridization, and immunohistochemistry. Slit2, Slit3, and Robo genes exhibited no expression changes at 3 hours; however, they were markedly upregulated 1 day after angioplasty. Intercellular CAM-1 expression was reduced by 50%, and the number of adventitial neutrophils decreased by >75% 1 day after angioplasty. Slit2 has been shown to be a potent chemorepelent of leukocytes, endothelial cells, and smooth muscle cells. Thus, we decided to further investigate the localization of Slit2 in injured vessels. Immunohistochemical stainings revealed the presence of Slit2 within the vessel wall and in the perivascular vasa vasorum of naive and injured arteries. Double immunohistochemical analyses showed that infiltrating monocytes expressed Slit2 in the perivascular and adventitial tissues of injured arteries 1 and 3 days postangioplasty. In addition, recombinant full-length Slit2 and Slit2-N/1118, an N-terminal fragment of Slit2, inhibited stromal cell-derived factor 1-mediated migration of circulating rat peripheral blood mononuclear cells. In summary, adventitial activation of CAM genes and neutrophil infiltration preceded

  5. Elicitation Approaches for Withanolide Production in Hairy Root Culture of Withania somnifera (L.) Dunal.

    Science.gov (United States)

    Sivanandhan, Ganeshan; Selvaraj, Natesan; Ganapathi, Andy; Manickavasagam, Markandan

    2016-01-01

    Withania somnifera (L.) Dunal is a versatile medicinal plant extensively utilized for production of phytochemical drug preparations. The roots and whole plants are traditionally used in Ayurveda, Unani, and Siddha medicines, as well as in homeopathy. Several studies provide evidence for an array of pharmaceutical properties due to the presence of steroidal lactones named "withanolides." A number of research groups have focused their attention on the effects of biotic and abiotic elicitors on withanolide production using cultures of adventitious roots, cell suspensions, shoot suspensions, and hairy roots in large-scale bioreactor for producing withanolides. This chapter explains the detailed procedures for induction and establishment of hairy roots from leaf explants of W. somnifera, proliferation and multiplication of hairy root cultures, estimation of withanolide productivity upon elicitation with salicylic acid and methyl jasmonate, and quantification of major withanolides by HPLC. The protocol herein described could be implemented for large-scale cultivation of hairy root biomass to improve withanolide production. PMID:26843160

  6. Auxin-Independent NAC Pathway Acts in Response to Explant-Specific Wounding and Promotes Root Tip Emergence during de Novo Root Organogenesis in Arabidopsis.

    Science.gov (United States)

    Chen, Xiaodong; Cheng, Jingfei; Chen, Lyuqin; Zhang, Guifang; Huang, Hai; Zhang, Yijing; Xu, Lin

    2016-04-01

    Plants have powerful regenerative abilities that allow them to recover from damage and survive in nature. De novo organogenesis is one type of plant regeneration in which adventitious roots and shoots are produced from wounded and detached organs. By studying de novo root organogenesis using leaf explants of Arabidopsis (Arabidopsis thaliana), we previously suggested that wounding is the first event that provides signals to trigger the whole regenerative process. However, our knowledge of the role of wounding in regeneration remains limited. In this study, we show that wounding not only triggers the auxin-mediated fate transition of regeneration-competent cells, but also induces the NAC pathway for root tip emergence. The NAC1 transcription factor gene was specifically expressed in response to wounding in the leaf explant, but not in the wounded leaf residue of the source plant. Inhibition of the NAC1 pathway severely affected the emergence of adventitious root tips. However, the NAC1 pathway functioned independently of auxin-mediated cell fate transition and regulates expression of CEP genes, which encode proteins that might have a role in degradation of extensin proteins in the cell wall. Overall, our results suggest that wounding has multiple roles in de novo root organogenesis and that NAC1 acts as one downstream branch in regulating the cellular environment for organ emergence.

  7. Adventitious shoot regeneration from the leaves of some pear varieties (Pyrus spp.) grown in vitro

    Institute of Scientific and Technical Information of China (English)

    Bharat Kumar POUDYAL; Yuxing ZHANG; Guoqiang DU

    2008-01-01

    The pear (Pyrus spp.) is one of the most important temperate fruit crops. A complete protocol for adventitious shoot regeneration was developed from the leaves of four pear varieties grown in vitro: Abbe Fetel, Yali, Packham's Triumph and Aikansui, and the Chinese rootstock variety Dull. Shoot explants were collected from the field and cultured in vitro in Murashige and acid (IBA). After four weeks, leaf explants of all 5 varieties grown in vitro were excised and cultured in MS cultures were maintained in darkness for 21 days for shoot induction in the shoot induction medium (IM), then transferred to the shoot expression medium (EM) in room at (25±2)℃ under a 16/8 h light/dark photoperiod regime for 8 weeks. Finally, the shoots were transferred to the MS shoot elongation medium (SEM) supplemented gibberellic acid (GA3). A combination of TDZ and NAA had a significant effect on the number of shoot regenera-tions in all 5 tested varieties. The maximum mean number of shoots and maximum number of shoots per leaf obtained from Yali variety were 11.8 (P≤0.001) and 22, followed by Aikansui with 6.6 (P≤0.001) and 4.6, and Duff with 8 (P≤0.001) and 12, all arising from the For Packham's Triumph and Abbe Fetel, the maximum mean number of shoots and maximum number of shoots per leaf were 5.6 (P≤0.001), 4.8 and 8 (P≤0.001), and 11, which produced significantly higher adventitious shoots problems associated with shoot proliferation and regenera-tion were also observed and discussed in this paper.

  8. Root fractures

    DEFF Research Database (Denmark)

    Andreasen, Jens Ove; Christensen, Søren Steno Ahrensburg; Tsilingaridis, Georgios

    2012-01-01

    The purpose of this study was to analyze tooth loss after root fractures and to assess the influence of the type of healing and the location of the root fracture. Furthermore, the actual cause of tooth loss was analyzed.......The purpose of this study was to analyze tooth loss after root fractures and to assess the influence of the type of healing and the location of the root fracture. Furthermore, the actual cause of tooth loss was analyzed....

  9. Square Root +

    Science.gov (United States)

    Frederiksen, John G.

    1969-01-01

    A rational presentation of the so-called long division method for extracting the square root of a number. Diagrams are used to show relationship of this technique to the binomial theorem. Presentation exposes student to many facets of mathematics in addition to the mechanics of funding square root and cube root. Geometry, algebraic statements,…

  10. Expression of Root-Related Transcription Factors Associated with Flooding Tolerance of Soybean (Glycine max

    Directory of Open Access Journals (Sweden)

    Babu Valliyodan

    2014-09-01

    Full Text Available Much research has been conducted on the changes in gene expression of the model plant Arabidopsis to low-oxygen stress. Flooding results in a low oxygen environment in the root zone. However, there is ample evidence that tolerance to soil flooding is more than tolerance to low oxygen alone. In this study, we investigated the physiological response and differential expression of root-related transcription factors (TFs associated with the tolerance of soybean plants to soil flooding. Differential responses of PI408105A and S99-2281 plants to ten days of soil flooding were evaluated at physiological, morphological and anatomical levels. Gene expression underlying the tolerance response was investigated using qRT-PCR of root-related TFs, known anaerobic genes, and housekeeping genes. Biomass of flood-sensitive S99-2281 roots remained unchanged during the entire 10 days of flooding. Flood-tolerant PI408105A plants exhibited recovery of root growth after 3 days of flooding. Flooding induced the development of aerenchyma and adventitious roots more rapidly in the flood-tolerant than the flood-sensitive genotype. Roots of tolerant plants also contained more ATP than roots of sensitive plants at the 7th and 10th days of flooding. Quantitative transcript analysis identified 132 genes differentially expressed between the two genotypes at one or more time points of flooding. Expression of genes related to the ethylene biosynthesis pathway and formation of adventitious roots was induced earlier and to higher levels in roots of the flood-tolerant genotype. Three potential flood-tolerance TFs which were differentially expressed between the two genotypes during the entire 10-day flooding duration were identified. This study confirmed the expression of anaerobic genes in response to soil flooding. Additionally, the differential expression of TFs associated with soil flooding tolerance was not qualitative but quantitative and temporal. Functional analyses of

  11. Screening conditions of adventitious bud induction and plantlet regeneration for Cunninghamia lanceolata%杉木茎段不定芽诱导及植株再生条件筛选

    Institute of Scientific and Technical Information of China (English)

    莫雅芳; 戴勤; 谭玲; 苏治南; 卢亮; 杨梅

    2013-01-01

    [目的]探索广西杉木快繁技术,为杉木组织培养和种苗供应提供参考依据.[方法]以杉木优良树种基部枝条为试验材料,进行茎段外植体消毒、不定芽诱导及植株再生研究.[结果]以75%酒精处理30 s+0.1%升汞消毒6min的效果较理想,污染率为30%;初代培养基为1/2MS+NAA 0.2 mg/L+6-BA 0.6 mg/L,第8d即有芽萌动,诱导率可达47%;继代培养基1/2MS +IBA 0.3 mg/L+6-BA 0.4 mg/L中加入蔗糖30 g/L,25 d腋芽增殖倍数可达3.4倍;1/4MS+IBA 0.15mg/L+NAA 0.075 mg/L对杉木生根诱导效果较好,生根率为52%.[结论],杉木外植体用75%酒精和0.1%升汞消毒6min效果较理想,适当减少培养基中矿质元素有利于杉木外殖体芽的诱导和试管苗的增殖生长,NAA可促进试管苗生根.%[Objective]Conditions of the adventitious bud induction and plant regeneration for Cunninghamia lanceolata were screened and rapid propagation techniques for Chinese fir in Guangxi was explored to provide references for supply and tissue culture of Chinese fir seedlings.[Method]Using base branches of superior Chinese fir species as testing materials,stem explant disinfection,adventitious bud induction and plant regeneration were the focal points in the current research.[Result] (1)The best disinfection method was treating stem explants with 75% ethanol for 30 s and 0.1% mercuric chloride for 6 min,which showed 30% contamination rate; (2)In the initial medium (1/2MS + NAA 0.2 mg/L + 6-BA 0.6 mg/L),the buds germinated on the 8th day with the induction rate of 47%; (3)In the optimum subculture medium (1/2MS + IBA 0.3 mg/L + 6-BA 0.6 mg/L + white sugar 30 g/L),axillary buds were multiplied by 3.4 times on the 25th day; (4)The induction effect was the best with the rooting rate of 52% in the rooting medium (1/4MS + IBA 0.15 mg/L + NAA 0.075 mg/L).[Conclusion]It was beneficial to the adventitious bud induction for Chinese fir with the initial medium (1/2MS + NAA 0.2 mg

  12. Ideal root architecture for phosphorus acquisition of plants under water and phosphorus coupled stresses: From simulation to application

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Under water and phosphorus (P) coupledstresses, root architecture may be related to P acquisition efficiency of plants. Understanding the relationship between root architecture and P acquisition efficiency may provide basic information for improving P acquisition efficiency of plants. In the present study, we quantitatively described the effects of root architecture on P acquisition efficiency by computer simulation together with controlled biological experiments so as to determine an ideal root architecture for efficient P acquisition under water and P coupled stresses.Our results indicate that under given soil water conditions,the ideal root architecture for P acquisition efficiency of a tap root plant (as represented by common bean) is an "umbrella-shape'' root system whose basal roots tend to be shallow in the P-rich topsoil and tap roots tend to be deep for water in the subsoil. Meanwhile, the ideal root architecture for a fibrous root plant (as represented by upland rice) is a "beard-shape" root system with the moderately dispersed yet uniformly distributed adventitious and lateral roots so as to keep most roots in the topsoil for P and a few roots in the subsoil for water.

  13. Direct Adventitious Bud Induction and Plant Regeneration of Rosa hybrida Samantha

    Institute of Scientific and Technical Information of China (English)

    GAO Li-ping; BAO Man-zhu

    2005-01-01

    Effect of explant, site of leaflet, induction period in the dark and combinations of plant growth regulators on direct adventitious bud induction and plant regeneration of Rosa hybrida Samantha was investigated. The results showed that after an induction period of 8 d on MS medium with 1.5 mg L-1 TDZ and 0.05 mg L-1 NAA in the dark and a subculture on MS medium with 0.5 mg L-1 BA and 0.01 mg L-1 NAA under light, the best plant regeneration was obtained and the regeneration frequencies of leaflets and petioles were 51.8 and 10% respectively. There was no significant difference in regeneration ability between leaflets at different sites of the compound leaves, longer time of induction in the dark or high concentration of auxin would cause callus formation, which was disadvantageous for shoot regeneration, and the regeneration frequency was significantly reduced. This regeneration system could be applied for genetic transformation of this cultivar in the future.

  14. Excessive Adventitial Remodeling Leads to Early Aortic Maladaptation in Angiotensin-Induced Hypertension.

    Science.gov (United States)

    Bersi, Matthew R; Bellini, Chiara; Wu, Jing; Montaniel, Kim R C; Harrison, David G; Humphrey, Jay D

    2016-05-01

    The primary function of central arteries is to store elastic energy during systole and to use it to sustain blood flow during diastole. Arterial stiffening compromises this normal mechanical function and adversely affects end organs, such as the brain, heart, and kidneys. Using an angiotensin II infusion model of hypertension in wild-type mice, we show that the thoracic aorta exhibits a dramatic loss of energy storage within 2 weeks that persists for at least 4 weeks. This diminished mechanical functionality results from increased structural stiffening as a result of an excessive accumulation of adventitial collagen, not a change in the intrinsic stiffness of the wall. A detailed analysis of the transmural biaxial wall stress suggests that the exuberant production of collagen results more from an inflammatory response than from a mechano-adaptation, hence reinforcing the need to control inflammation, not just blood pressure. Although most clinical assessments of arterial stiffening focus on intimal-medial thickening, these results suggest a need to measure and control the highly active and important adventitia. PMID:27001298

  15. Structure of a murine norovirus NS6 protease-product complex revealed by adventitious crystallisation.

    Directory of Open Access Journals (Sweden)

    Eoin N Leen

    Full Text Available Murine noroviruses have emerged as a valuable tool for investigating the molecular basis of infection and pathogenesis of the closely related human noroviruses, which are the major cause of non-bacterial gastroenteritis. The replication of noroviruses relies on the proteolytic processing of a large polyprotein precursor into six non-structural proteins (NS1-2, NS3, NS4, NS5, NS6(pro, NS7(pol by the virally-encoded NS6 protease. We report here the crystal structure of MNV NS6(pro, which has been determined to a resolution of 1.6 Å. Adventitiously, the crystal contacts are mediated in part by the binding of the C-terminus of NS6(pro within the peptide-binding cleft of a neighbouring molecule. This insertion occurs for both molecules in the asymmetric unit of the crystal in a manner that is consistent with physiologically-relevant binding, thereby providing two independent views of a protease-peptide complex. Since the NS6(pro C-terminus is formed in vivo by NS6(pro processing, these crystal contacts replicate the protease-product complex that is formed immediately following cleavage of the peptide bond at the NS6-NS7 junction. The observed mode of binding of the C-terminal product peptide yields new insights into the structural basis of NS6(pro specificity.

  16. Relation of Root Growth of Rice Seedling with Nutrition and Water Use Efficiency Under Different Water Supply Conditions

    Institute of Scientific and Technical Information of China (English)

    ZHENG Bing-song; JIANG De-an; WU Ping; WENG Xiao-yan; LU Qing; WANG Ni-yan

    2006-01-01

    Water deficiency is one of the primary yield-limiting factors in rice. In plants, the nutrition and water use efficiency depend on root growth efficiency under different water supply conditions (WSC). Three rice genotypes, Azucena (an upland japonica),IR1552 (a lowland indica) and Jia 9522 (a lowland japonica), were grown under different WSC with 0 cm (submerged), 40 cm and 80cm groundwater levels below the soil surface to investigate the root parameters, water use efficiency, nitrogen, phosphorous and potassium contents, net photosynthetic rate and transpiration rate of the rice plant. The relative parameters were defined as the ratio of the parameters under submerged conditions (0 cm groundwater level below soil surface) to these under upland conditions (40 cm and 80 cm groundwater levels below soil surface). The results indicated that different genotypes showed different relative root parameters and relative nutrition content and water use efficiency under different WSC. The length and number of adventitious root are more important than seminal root length in water and nutrition uptake, and maintaining the grain yield and increasing dry matter,but the adventitious root number could not be served as an index for screening drought-resistant genotypes. Furthermore, different drought-resistant genotypes have been also found, and Azucena was resistant to drought, IR1552 sensitive to drought and Jia 9522neither sensitive nor resistant to drought.

  17. Root patterning

    NARCIS (Netherlands)

    Scheres, Ben; Laskowski, Marta

    2016-01-01

    The mechanisms that pattern lateral root primordial are essential for the elaboration of root system architecture, a trait of key importance for future crop breeding. But which are most important: periodic or local cues? In this issue of Journal of Experimental Botany (pages 1411-1420), Kircher a

  18. Development and Function of Root System of Trapa quadrispinosa Roxb.%四角菱根系的发育和功能

    Institute of Scientific and Technical Information of China (English)

    陆昌燕; 刘体育; 郑兴峰

    2011-01-01

    [ Objective ] This paper aimed to explore the adaptive characteristics of development and function of the root system of Trapa quadrispinosa Roxb. [ Method ] Observation was conducted on the growth and development from the seedling cultivated in artificial water channels, and comparison in the cultivation was done of normal plants and treated plants in three groups of separately excising off adventitious roots,pinnate appendices (special adventitious roots) ,and adventitious roots and pinnate appendices [ Result ] The radical and the pinnate appendices both grew determinately, and the apex of radical presented browning death after the radical stopped growth. The adventitious roots on the base of radical and the node of stem grew downwards and spirally into the tier of soil under water body. The pinnate appendix was generally with four lines of branches in radial symmetry. After only the root,and both the adventitious root and the pinnate appendix were excised off, etiolating of the new floating leaf occurred, however,if only the pinnate appendix was cut away, the new floating leaf kept green. [ Conclusion ] The adventitious root system, which continually arose towards the stem apex along with growth of the stem and was in stead of the root system from the radical, can better fix its plant which was thin and floating in water body, and was with important absorption function. The pinnate appendix was a complementary photosynthetic organ of specialized adventitious root.%[目的]研究四角菱(Trapa quadrispinosa Roxb.)根系的发育和功能适应性特征.[方法]采用人工水槽对四角菱幼苗进行培养观察,设置切除不定根、切除羽状物(特化不定根)以及同时切除不定根和羽状物3个处理,并与正常生长的植株进行对比.[结果]四角菱的胚根和羽状物进行有限生长,胚根停止生长后顶端出现褐化死亡;胚根基部和茎节上的不定根向水底泥层生长,并在泥层中弯曲生

  19. Progression Rates of Carotid Intima-media Thickness and Adventitial Diameter during the Menopausal Transition

    Science.gov (United States)

    El Khoudary, Samar R.; Wildman, Rachel P.; Matthews, Karen; Thurston, Rebecca C.; Bromberger, Joyce T.; Sutton-Tyrrell, Kim

    2012-01-01

    Objectives The authors assessed whether the levels and progression rates of carotid intima-media thickness (IMT) and adventitial diameter (AD) vary by menopausal stage. Methods 249 Women (42–57 years old, premenopausal (49%) or early peri-menopausal (46%)) from the Study of Women’s Health Across the Nation were included in the current analysis. Participants were followed for up to 9 years (median=3.7 years) and had up to 5 carotid scans. Linear mixed models were used for analysis. Results The overall rate of change in IMT was 0.007 mm/year. Independent of age and race, progression rate of IMT increased substantially in late peri-menopausal stage (0.017 mm/year) compared to both premenopausal (0.007 mm/year) and early peri-menopausal (0.005 mm/year) stages; (P≤0.05). For AD, while the overall rate of change was negative (−0.009 mm/year), significant positive increases in the rate of change were observed in late peri-menopausal (0.024 mm/year) and postmenopausal (0.018 mm/year) stages compared to premenopausal stage (−0.032 mm/year); (P<0.05). In final models, postmenopausal stage was independently associated with higher levels of IMT and AD (P<0.05) compared to premenopausal stage. Conclusions During the menopausal transition, the carotid artery undergoes an adaptation that is reflected in adverse changes in IMT and AD. These changes may impact the vulnerability of the vessel to disease in older women. PMID:22990755

  20. Root resorption

    DEFF Research Database (Denmark)

    Kjaer, Inger

    2014-01-01

    -an ectodermal tissue layer (Malassez′s epithelium), a middle layer-composed by the collagen-mesodermal tissue layer, and an innermost root-close innervation layer. Abnormalities in one of these tissue layers are thought to cause inflammatory processes in the periodontal membrane comparable to inflammatory...... formerly been demonstrated how demyelinization of the myelin sheaths in the peripheral nerves close to the root provoke resorption. Accordingly, conditions affecting these tissue layers can be associated not only with different morphologies but also with general symptoms and diseases (e.g., ectodermal...... orthodontic treatment. The Hypothesis: The hypothesis in this paper is that three different tissue layers covering the root in the so-called periroot sheet can explain signs and symptoms of importance for avoiding root resorption during orthodontic treatment. These different tissue layers are; outermost...

  1. The influence of fertilization on quality of inflorescences of easy pot freesia (Freesia Eckl. ex Klatt) grown from adventitious corms

    OpenAIRE

    Piotr Żurawik; Monika Placek

    2012-01-01

    The experiments were carried out in 2006-2007, in the spring-summer season, in an unheated plastic tunnel. Adventitious corms of Easy Pot Freesia: 'Gompey', 'Popey' and 'Suzy', were the plant material. The influence of a traditional fertilizer Azofoska and slow-release fertilizers, Osmocote Plus 5/6, Osmocote Exact and Polyon 5/6, on the ornamental value of plants was evaluated. All fertilizers were applied at rates of 2.5 and 5.0 g × dm-3. Freesias cultivated without fertilizer were the cont...

  2. Percutaneous ethanol sclerotherapy for recurrent adventitial cystic disease of external iliac vein after surgical treatment: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Ann, Jun Hyung; Kim, Jeong Ho; Byun, Sung Su; Kang, Jin Mo; Kim, Hyung Sik; Choi, Hye Young [Gachon University Gil Medical Center, Incheon (Korea, Republic of)

    2015-12-15

    Adventitial cystic disease (ACD) is a rare, but well-characterized vascular disease. It is most commonly seen in the popliteal artery, but it has also been reported in the venous system. The most commonly involved segment has been the common femoral vein; the disease resulted in luminal compromise and extremity swelling. We report here on a case of percutaneous aspiration and ethanol sclerotherapy for recurrent ACD after surgery of the external iliac vein in a 70-year-old man who presented with a painless swelling of his left leg.

  3. Rooting of cuttings of vanilla plant (Orchidaceae) /
    Enraizamento de estacas da baunilheira (Orchidaceae)

    OpenAIRE

    Aparecida Gomes de Araujo; José Maria Moreira Dias; Flávio Pereira Silva; Moacir Pasqual; Maria das Dôres David Silva

    2009-01-01

    The vanilla plant (Vanilla planifolia) could have a higher commercial production but there are problems in the efficiency of propagation. The present work was conducted with the aim of studying the effect of different substrates, in the adventitious rooting of cuttings taken at five heights in the plant stem. The cuttings were 20cm long and had two buds and one leaf and were planted in: 1) Liquid medium formed by Clark’s nutrient added of 2.5mg L-1 of IBA placed in plastic foam box with a cap...

  4. Ecophysiology of wetland plant roots: A modelling comparison of aeration in relation to species distribution

    Science.gov (United States)

    Sorrell, B.K.; Mendelssohn, I.A.; McKee, K.L.; Woods, R.A.

    2000-01-01

    This study examined the potential for inter-specific differences in root aeration to determine wetland plant distribution in nature. We compared aeration in species that differ in the type of sediment and depth of water they colonize. Differences in root anatomy, structure and physiology were applied to aeration models that predicted the maximum possible aerobic lengths and development of anoxic zones in primary adventitious roots. Differences in anatomy and metabolism that provided higher axial fluxes of oxygen allowed deeper root growth in species that favour more reducing sediments and deeper water. Modelling identified factors that affected growth in anoxic soils through their effects on aeration. These included lateral root formation, which occurred at the expense of extension of the primary root because of the additional respiratory demand they imposed, reducing oxygen fluxes to the tip and stele, and the development of stelar anoxia. However, changes in sediment oxygen demand had little detectable effect on aeration in the primary roots due to their low wall permeability and high surface impedance, but appeared to reduce internal oxygen availability by accelerating loss from laterals. The development of pressurized convective gas flow in shoots and rhizomes was also found to be important in assisting root aeration, as it maintained higher basal oxygen concentrations at the rhizome-root junctions in species growing into deep water. (C) 2000 Annals of Botany Company.

  5. Chronic adventitial inflammation, vasa vasorum expansion, and 5-lipoxygenase up-regulation in irradiated arteries from cancer survivors

    Science.gov (United States)

    Halle, Martin; Christersdottir, Tinna; Bäck, Magnus

    2016-01-01

    Radiation-induced cardiovascular disease is an emerging problem in a steadily increasing population of survivors of cancer. However, the underlying biology is poorly described, and the late onset, which occurs several years after exposure, precludes adequate investigations in animal and cell culture models. We investigated the role of the 5-lipoxygenase (5-LO)/leukotriene pathway in radiation-induced vascular changes. Use of paired samples of irradiated arteries and nonirradiated internal control arteries from the same patient that were harvested during surgery for cancer reconstruction ≤10 yr after radiotherapy provides a unique human model of chronic radiation–induced vascular changes. Immunohistochemical stainings and perioperative inspection revealed an adventitial inflammatory response, with vasa vasorum expansion and chronic infiltration of CD68+ macrophages. These macrophages stained positive for the leukotriene-forming enzyme 5-LO. Messenger RNA levels of 5-LO and leukotriene B4 receptor 1 were increased in irradiated arterial segments compared with control vessels. These results point to targeting the 5-LO/leukotriene pathway as a therapeutic adjunct to prevent late adverse vascular effects of radiotherapy.—Halle, M., Christersdottir, T., Bäck, M. Chronic adventitial inflammation, vasa vasorum expansion, and 5-lipoxygenase up-regulation in irradiated arteries from cancer survivors. PMID:27530979

  6. Selection of Common Bean Lines, Recombinant Inbred Lines and Commercial Genotypes Tolerant to Low Phosphorus Availability in an Acrisol Soil on the Basis of Root Traits and Grain Yield

    International Nuclear Information System (INIS)

    Common bean (Phaseolus vulgaris L.) is the most important food legume for human consumption worldwide and especially in Latin America and Africa, but low soil phosphorus (P) availability limits grain production in these areas. For these reason eighty five recombinant inbred lines (RILs) of BAT 477 x DOR 364 and twenty commercial bean genotypes were sown in plots in an Acrisol soil with low P availability to evaluate nine root traits and grain yield. The study was carried out in Pinar del Rio province in Cuba between November 2006 and February 2009. The plots received basal fertilization (N and K) and P fertilization between 15 and 90 kg P2O5 ha-1. Ten plants were sampled from each plot at R6 pod fill to evaluate root traits and shoot biomass, and at R9 physiological maturity to estimate grain yield. The 85 RILs showed great variability for root traits, grain yield and P stress tolerance calculated as relative grain yield. The commercial bean lines also showed large diversity in yield parameters. Principal Component Analysis showed that there were high and significant correlations between root traits (basal root number, primary root depth, adventitious root length and adventitious root number) and grain yield parameters (grain yield at 15 P level and relative grain yields). Adventitious root traits showed the greatest correlation with yield under low P. Promising RILs included 75.1.1, 60.1.1, 38.1.1, 14.1.1 and 38.1.1 and promising commercial bean lines included ICA Pijao, BAT 482, ICA 23, BAT 24 and BAT 832. (author)

  7. Anatomy and Histochemistry of Roots and Shoots in Wild Rice (Zizania latifolia Griseb.

    Directory of Open Access Journals (Sweden)

    Chaodong Yang

    2014-01-01

    Full Text Available Wild rice (Zizania latifolia Griseb. is a famous, perennial, emergent vegetable in China. The current work explores the anatomy and histochemistry of roots, stems, and leaves and the permeability of apoplastic barriers of wild rice. The adventitious roots in wild rice have suberized and lignified endodermis and adjacent, thick-walled cortical layers and suberized and lignified hypodermis, composed of a uniseriate sclerenchyma layer (SC underlying uniseriate exodermis; they also have lysigenous aerenchyma. Stems have a thickened epidermal cuticle, a narrow peripheral mechanical ring (PMR, an outer ring of vascular bundles, and an inner ring of vascular bundles embedded in a multiseriate sclerenchyma ring (SCR. There is evidence of suberin in stem SCR and PMR sclerenchyma cells. Sheathing leaves are characterized by thick cuticles and fibrous bundle sheath extensions. Air spaces in stems and leaves consist of mostly lysigenous aerenchyma and pith cavities in stems. Apoplastic barriers are found in roots and stems.

  8. Root canal

    Science.gov (United States)

    Endodontic therapy ... the root of a tooth. Generally, there is pain and swelling in the area. The infection can ... You may have some pain or soreness after the procedure. An over-the-counter anti-inflammatory drug, such as ibuprofen or naproxen, can help relieve ...

  9. Preliminary Observation on Developmental Characteristics of Adventitious Buds of Artemisia frigida Willd.%冷蒿不定芽发育特性的初步观察

    Institute of Scientific and Technical Information of China (English)

    李姗姗; 宛涛; 蔡萍; 伊卫东; 韩轩

    2013-01-01

    对冷蒿不定芽的分布、着生特点、萌生数量及形态结构特征等发育特性的初步观察表明:冷蒿不定芽主要着生于根颈、地表枝条上,其大小、数量以及分布情况各异;不定芽主要产生于返青期到结实期,冷蒿现蕾期和开花期是不定芽萌生的旺盛时期,在根颈处分别有19个和25个,地表枝条上有66个和75个.光镜和扫描电镜观察表明,不定芽具有芽鳞片,包裹着幼叶、叶原基和叶生长点,芽和叶片的表皮被有大量的白色绢毛,发育中的芽体由灰白色转变为绿色,最终发育成叶片和枝条.%The developmental characteristics of adventitious buds of Artemisia frigida Willd. were observed. The results show that the adventitious buds of Artemisia frigida Willd. mainly grow on the rhizome and ground branches,whose size, amount and distribution were different; adventitious buds occurred in May to November, budding stage and flowering stage were period of adventitious buds occurring, there were 19 and 25 adventitious buds on the rhizome and 66 and 75 adventitious buds on the ground branches; by the optical stereoscope and canning electron microscope, the adventitious buds had bud scale, young leaves, leaf primordium and growing tip wrapped in it, the surface of buds and leaves had plenty of white silk wool, the buds turned off-white to green during development, finally formed leaf and branch.

  10. [Induction of polyploid hairy roots and its plant regeneration in Pogostemon cablin].

    Science.gov (United States)

    Shi, Heping; Yu, Wu; Zhang, Guopeng; Tsang, Pokeung Eric; Chow, Cheuk Fai Stephen

    2014-08-01

    Abstract: In order to enhance the content of secondary metabolites patchouli alcohol in Pogostemon cablin, we induced polyploid hairy roots and their plant regeneration, and determined the content of patchouli alcohol through artificial chromosome doubling with colchicine. The highest rate of polyploidy induction was more than 40% when hairy roots were treated with 0.05% colchicine for 36 h. The obtained polyploid hairy roots formed adventitious shoots when cultured in an MS medium with 6-BA 0.2 mg/L and NAA 0.1 mg/L for 60 d. Compared with the control diploid plants, the polyploid hairy root-regenerated plants of P. cablin had more developed root systems, thicker stems, shorter internodes and longer, wider and thicker leaves. Observation of the chromosome number in their root tip cells reveals that the obtained polyploid regenerated plants were tetraploidy, with 128 (4n = 128) chromosomes. The leaves contained around twice as many stomatal guard cells and chloroplasts as the controls, but the stomatal density declined with increasing ploidy. The stomatal density in diploid plants was around 1.67 times of that in polyploid plants. GC-MS analysis shows that the content of patchouli alcholol in the hairy root-derived polyploid plants was about 4.25 mg/g dry weight, which was 2.3 times of that in diploid plants. The present study demonstrates that polyploidization of hairy roots can stimulate the content of patchouli alcholol in medicinal plant of P. cablin. PMID:25507476

  11. Plant hairy root cultures as plasmodium modulators of the slime mold emergent computing substrate Physarum polycephalum

    Directory of Open Access Journals (Sweden)

    Vincent eRicigliano

    2015-07-01

    Full Text Available Roots of the medicinal plant Valeriana officinalis are well studied for their various biological activities. We applied genetically transformed V. officinalis root cultures to exert control of Physarum polycephalum, an amoeba-based emergent computing substrate. The plasmodial stage of the P. polycephalum life cycle constitutes a single, multinucleate cell visible by unaided eye. The plasmodium modifies its network of oscillating protoplasm in response to spatial configurations of attractants and repellents, a behavior that is interpreted as biological computation. To program the computing behavior of P. polycephalum, a diverse and sustainable library of plasmodium modulators is required. Hairy roots produced by genetic transformation with Agrobacterium rhizogenes are a metabolically stable source of plant natural products. Adventitious roots were induced on in vitro V. officinalis plants following infection with A. rhizogenes. A single hairy root clone was selected for massive propagation and the biomass was characterized in P. polycephalum chemotaxis, maze-solving, and electrical activity assays. The Agrobacterium-derived roots of V. officinalis elicited a positive chemotactic response and augmented maze-solving behavior. In a simple plasmodium circuit, introduction of hairy root biomass stimulated the oscillation patterns of slime mold’s surface electrical potential. We propose that manipulation of P. polycephalum with the V. officinalis root culture platform can be applied to the development of slime mold microfluidic devices as well as future models for engineering the plant rhizosphere.

  12. Plant hairy root cultures as plasmodium modulators of the slime mold emergent computing substrate Physarum polycephalum.

    Science.gov (United States)

    Ricigliano, Vincent; Chitaman, Javed; Tong, Jingjing; Adamatzky, Andrew; Howarth, Dianella G

    2015-01-01

    Roots of the medicinal plant Valeriana officinalis are well-studied for their various biological activities. We applied genetically transformed V. officinalis root biomass to exert control of Physarum polycephalum, an amoeba-based emergent computing substrate. The plasmodial stage of the P. polycephalum life cycle constitutes a single, multinucleate cell visible by unaided eye. The plasmodium modifies its network of oscillating protoplasm in response to spatial configurations of attractants and repellents, a behavior that is interpreted as biological computation. To program the computing behavior of P. polycephalum, a diverse and sustainable library of plasmodium modulators is required. Hairy roots produced by genetic transformation with Agrobacterium rhizogenes are a metabolically stable source of bioactive compounds. Adventitious roots were induced on in vitro V. officinalis plants following infection with A. rhizogenes. A single hairy root clone was selected for massive propagation and the biomass was characterized in P. polycephalum chemotaxis, maze-solving, and electrical activity assays. The Agrobacterium-derived roots of V. officinalis elicited a positive chemotactic response and augmented maze-solving behavior. In a simple plasmodium circuit, introduction of hairy root biomass stimulated the oscillation patterns of slime mold's surface electrical activity. We propose that manipulation of P. polycephalum with the plant root culture platform can be applied to the development of slime mold microfluidic devices as well as future models for engineering the plant rhizosphere. PMID:26236301

  13. Locally Finite Root Supersystems

    OpenAIRE

    YOUSOFZADEH, Malihe

    2013-01-01

    We introduce the notion of locally finite root supersystems as a generalization of both locally finite root systems and generalized root systems. We classify irreducible locally finite root supersystems.

  14. Calogênese e brotações adventícias em tecido somático de Kiwi suplementados com Thidiazuron Callogenesis and adventitious shoots in Kiwi somatic tissue suplemented with Thidiazuron

    Directory of Open Access Journals (Sweden)

    Eva Choer

    1997-08-01

    concentrations of Thidiazuron (8 and 16mg/l were phytotoxic, leading to explant death. Rooting was observed only in the control treatment. Callus intensity formation, adventitious shoots number, callus dry matter weight and bud number showed a quadratic response to the Thidiazuron concentrations. Concentrations of Thidimuron were not efficient to increase the adventitious shoot number of Kiwi. Callus intensity increased until 2.21 mg/l Thidiazuron concentrations, and declined afterwards.

  15. Endogenous isoflavone methylation correlates with the in vitro rooting phases of Spartium junceum L. (Leguminosae).

    Science.gov (United States)

    Clematis, Francesca; Viglione, Serena; Beruto, Margherita; Lanzotti, Virginia; Dolci, Paola; Poncet, Christine; Curir, Paolo

    2014-09-01

    Spartium junceum L. (Leguminosae) is a perennial shrub, native to the Mediterranean region in southern Europe, widespread in all the Italian regions and, as a leguminous species, it has a high isoflavone content. An in vitro culture protocol was developed for this species starting from stem nodal sections of in vivo plants, and isoflavone components of the in vitro cultured tissues were studied by means of High Performance Liquid Chromatography (HPLC) analytical techniques. Two main isoflavones were detected in the S. junceum tissues during the in vitro propagation phases: Genistein (4',5,7-Trihydroxyisoflavone), already reported in this species, and its methylated form 4',5,7-Trimethoxyisoflavone, detected for the first time in this plant species (0.750 ± 0.02 mg g(-1) dry tissue). The presence of both of these compounds in S. junceum tissues was consistently detected during the in vitro multiplication phase. The absence of the methylated form within plant tissues in the early phases of the in vitro adventitious root formation was correlated with its negative effect displayed on root induction and initiation phases, while its presence in the final "root manifestation" phase influenced positively the rooting process. The unmethylated form, although detectable in tissues in the precocious rooting phases, was no longer present in the final rooting phase. Its effect on rooting, however, proved always to be beneficial. PMID:25014262

  16. Modeling gene flow distribution within conventional fields and development of a simplified sampling method to quantify adventitious GM contents in maize.

    Science.gov (United States)

    Melé, Enric; Nadal, Anna; Messeguer, Joaquima; Melé-Messeguer, Marina; Palaudelmàs, Montserrat; Peñas, Gisela; Piferrer, Xavier; Capellades, Gemma; Serra, Joan; Pla, Maria

    2015-01-01

    Genetically modified (GM) crops have been commercially grown for two decades. GM maize is one of 3 species with the highest acreage and specific events. Many countries established a mandatory labeling of products containing GM material, with thresholds for adventitious presence, to support consumers' freedom of choice. In consequence, coexistence systems need to be introduced to facilitate commercial culture of GM and non-GM crops in the same agricultural area. On modeling adventitious GM cross-pollination distribution within maize fields, we deduced a simple equation to estimate overall GM contents (%GM) of conventional fields, irrespective of its shape and size, and with no previous information on possible GM pollen donor fields. A sampling strategy was designed and experimentally validated in 19 agricultural fields. With 9 samples, %GM quantification requires just one analytical GM determination while identification of the pollen source needs 9 additional analyses. A decision support tool is provided. PMID:26596213

  17. Effect of aluminium on in vitro rooting of birch (Betula pendula Roth. and poplar (Populus tremula L. x P. alba L. microcuttings

    Directory of Open Access Journals (Sweden)

    Krystyna Bojarczuk

    2014-02-01

    Full Text Available Poplar (Populus tremula L. x P. alba L. and birch (Betula pendula Roth. microcuttings obtained from in vitro cultures on media with aluminium (Al+ or without aluminium (Al- were rooted in perlite saturated with a liquid 1/4 MS medium. Aluminium was added to the rooting medium in the form of aluminium sulphate or aluminium chloride. In the control, i.e. in the medium without aluminium, Al+ and Al- shoots usually developed similarly. Addition of aluminium to the rooting medium had a negative effect on the development of adventitious roots. Poplar and birch shoots obtained from cultures on media with aluminium (AI+ were distinguished by a greater tolerance of aluminium in the medium than shoots obtained from cultures on media without aluminium (A1-.

  18. Study on Rooting Culture and Rooting Anatomy of Tree Peony 'Wulong Pengsheng' Regenerated Shoots%牡丹‘乌龙捧盛’组培苗生根及生根解剖学研究

    Institute of Scientific and Technical Information of China (English)

    贾文庆; 徐小博; 刘会超; 李纪元

    2013-01-01

    The tissue-cultured seedlings of tree peony ‘ Wulong Pengsheng' were used to study the effects of different plant growth regulators,culture methods,and holdfast on rooting.The morphological structure change during rooting was also observed using the method of paraffin section.The result showed that the best combination of plant growth regulators for rooting was IBA 3.0 mg · L-1 + NAA 0.6 mg · L-1.The treatment under the temperature of 4℃ for ten days was benefit to rooting,and the rate could reach 75.67%.It was identified that the adventitious root primordia of shoot in vitro originated from the vascular cambium cells,especially,the cross areas of cambium and pith ray and they started to differentiate at the 5th day and lasted to the 12th day.If the shoots were cultured in the root inducing medium for 12 days,it would lead to not only descend of rooting rate,but also showing callus of stem base,and leaf senescent.However,if they were transferred into the medium without hormone in time,the root primordial protruded the epidermis and developed normally after 5 days' culture.

  19. Afrokoko Roots

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Give us a little background information about Afrokoko Roots.How long have you been performing together?It's an international Afrobeat outfit that I founded in Beijing three years ago.I founded it in order to show Chinese people that Africa is beyond what they see and hear on TV.For the purpose of cultural exchange,I hope it can help the Chinese learn about African culture,music,fashion,history and much more.Our band features two dancers,two backup singers,two percussionists,four brass players,a keyboard player,a guitar player and a drummer- and me as the lead vocal,drummer and dancer,which makes for live performances that are equally exciting sonically as they are visually.We have been traveling around,and so far,we have toured and performed in many Chinese cities such as Dalian (Liaoning Province),Hohhot (Inner Mongolia Autonomous Region) and Haikou (Hainan Province).

  20. The influence of fertilization on quality of inflorescences of easy pot freesia (Freesia Eckl. ex Klatt grown from adventitious corms

    Directory of Open Access Journals (Sweden)

    Piotr Żurawik

    2012-12-01

    Full Text Available The experiments were carried out in 2006-2007, in the spring-summer season, in an unheated plastic tunnel. Adventitious corms of Easy Pot Freesia: 'Gompey', 'Popey' and 'Suzy', were the plant material. The influence of a traditional fertilizer Azofoska and slow-release fertilizers, Osmocote Plus 5/6, Osmocote Exact and Polyon 5/6, on the ornamental value of plants was evaluated. All fertilizers were applied at rates of 2.5 and 5.0 g × dm-3. Freesias cultivated without fertilizer were the control plants. The cultivar 'Gompey' was characterized by longer inflorescence shoots and flowers of greater diameter, while the cultivar 'Suzy' had more flowers than the plants of the other cultivars evaluated. Plants with the greatest number of flowers and the longest inflorescences and shoots were obtained when slow-release fertilizers Osmocote Plus 5/6 and Osmocote Exact were used, regardless of cultivar and fertilizer dose. Polyon was useless for freesia fertilization, since it resulted in a decrease of the ornamental value of plants. Plants fertilized with Polyon had fewer flowers, additionally with a smaller diameter, and their inflorescences were shorter and deformed.

  1. Evidence for vocal learning in juvenile male killer whales, Orcinus orca, from an adventitious cross-socializing experiment.

    Science.gov (United States)

    Crance, Jessica L; Bowles, Ann E; Garver, Alan

    2014-04-15

    Killer whales (Orcinus orca) are thought to learn their vocal dialect. Dispersal in the species is rare, but effects of shifts in social association on the dialect can be studied under controlled conditions. Individual call repertoires and social association were measured in three adult female killer whales and three males (two juveniles and an adult) during two periods, 2001-2003 and 2005-2006. Three distinct dialect repertoires were represented among the subjects. An adventitious experiment in social change resulted from the birth of a calf and the transfer of two non-focal subjects in 2004. Across the two periods, 1691 calls were collected, categorized and attributed to individuals. Repertoire overlap for each subject dyad was compared with an index of association. During 2005-2006, the two juvenile males increased association with the unrelated adult male. By the end of the period, both had begun producing novel calls and call features characteristic of his repertoire. However, there was little or no reciprocal change and the adult females did not acquire his calls. Repertoire overlap and association were significantly correlated in the first period. In the second, median association time and repertoire similarity increased, but the relationship was only marginally significant. The results provided evidence that juvenile male killer whales are capable of learning new call types, possibly stimulated by a change in social association. The pattern of learning was consistent with a selective convergence of male repertoires. PMID:24744421

  2. Micropropagation of Codiaeum variegatum (L.) Blume and regeneration induction via adventitious buds and somatic embryogenesis.

    Science.gov (United States)

    Radice, Silvia

    2010-01-01

    Codiaeum variegatum (L) Blume cv. "Corazon de oro" and cv. "Norma" are successfully micropropagated when culture are initiated with explants taken from newly sprouted shoots. The establishment and multiplication steps are possible when 1 mg/L BA or 1 mg/L IAA and 3 mg/L 2iP are added to MS medium, according to the cultivar respectively selected.Adventive organogenesis and somatic embryogenesis are induced from leaf explants taken from in vitro buds of croton. On leaf-sectioned of "Corazon de oro" cultured in vitro, 1 mg/L BA stimulates continuous somatic embryos development and induces some shoots too. Replacing BA with 1 mg/L TDZ induces up to 100% bud regeneration in the same explants. On the other hand, leaf-sectioned of C. variegatum cv. Norma does not start somatic embryo differentiation if 1 mg/L TDZ is not added to the MS basal medium. Incipient callus is observed after 30 days of culture, and then, subculture to MS with 1 mg/L BA allows the same process to show on the "Corazon de oro" cultivar. Somatic embryos show growth arrest that is partially overcome by transfer to hormone-free basal medium with activated charcoal. Root induction is possible on basal medium plus 1 mg/L IBA. Plantlets in the greenhouse have variegated leaves true-to-type.

  3. 丹桂品种'堰虹桂'扦插繁殖条件与生根特征研究%Cutting propagating technology and rooting characters of Osmanthusfragrans‘Yanhong’

    Institute of Scientific and Technical Information of China (English)

    董立格; 王贤荣

    2011-01-01

    对桂花丹桂品种堰虹桂(Osmanthus fragrans'Yanhong')在不同质量浓度NAA、IBA和IAA处理下的扦插生根情况进行了观察和分析.结果表明,堰虹桂插穗生根类型为皮部生根型;以1.00 g·L-1 IBA处理插穗生根效果最好,愈伤组织和不定根出现最早,生根率可达94.71%,平均生根数和平均根长均优于其他处理.%Effects of different kinds of growth regulator with different concentrations on rooting of softwood cuttings of Osmanthusfragrans‘Yanhong'were investigated. The results showed that the cuttings taking root type of shin; 1.00 g-L-1 IBA treatment has the best effectiveness with the earliest appearance of callus and adventitious roots, and the rooting rate could reach 94.71%. Moreover, the quality of adventitious root numbers and length is the best.

  4. GENOME ENABLED MODIFICATION OF POPLAR ROOT DEVELOPMENT FOR INCREASED CARBON SEQUESTRATION

    Energy Technology Data Exchange (ETDEWEB)

    Busov, Victor

    2013-03-05

    DR5 as a reporter system to study auxin response in Populus Plant Cell Reports 32:453-463 Auxin responsive promoter DR5 reporter system is functional in Populus to monitor auxin response in tissues including leaves, roots, and stems. We described the behavior of the DR5::GUS reporter system in stably transformed Populus plants. We found several similarities with Arabidopsis, including sensitivity to native and synthetic auxins, rapid induction after treatment in a variety of tissues, and maximal responses in root tissues. There were also several important differences from Arabidopsis, including slower time to maximum response and lower induction amplitude. Young leaves and stem sections below the apex showed much higher DR5 activity than did older leaves and stems undergoing secondary growth. DR5 activity was highest in cortex, suggesting high levels of auxin concentration and/or sensitivity in this tissue. Our study shows that the DR5 reporter system is a sensitive and facile system for monitoring auxin responses and distribution at cellular resolution in poplar. The Populus AINTEGUMENTA LIKE 1 homeotic transcription factor PtAIL1 controls the formation of adventitious root primordia. Plant Physiol. 160: 1996-2006 Adventitious rooting is an essential but sometimes rate-limiting step in the clonal multiplication of elite tree germplasm, because the ability to form roots declines rapidly with age in mature adult plant tissues. In spite of the importance of adventitious rooting, the mechanism behind this developmental process remains poorly understood. We have described the transcriptional profiles that are associated with the developmental stages of adventitious root formation in the model tree poplar (Populus trichocarpa). Transcriptome analyses indicate a highly specific temporal induction of the AINTEGUMENTA LIKE1 (PtAIL1) transcription factor of the AP2 family during adventitious root formation. Transgenic poplar samples that overexpressed PtAIL1 were able to

  5. Root canal irrigants

    OpenAIRE

    Kandaswamy Deivanayagam; Venkateshbabu Nagendrababu

    2010-01-01

    Successful root canal therapy relies on the combination of proper instrumentation, irrigation, and obturation of the root canal. Of these three essential steps of root canal therapy, irrigation of the root canal is the most important determinant in the healing of the periapical tissues. The primary endodontic treatment goal must thus be to optimize root canal disinfection and to prevent reinfection. In this review of the literature, various irrigants and the interactions between irrigants are...

  6. Effects of ion beam irradiation on adventitious shoot regeneration from in vitro leaf explants of Septennial ionahta

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, L.B. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China)]. E-mail: libinzhou@impcas.ac.cn; Li, W.J. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Ma, S. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Dong, X.C. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Yu, L.X. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Li, Q. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Zhou, G.M. [Radiobiology Department, Institute of Modern Physics, Chinese Academy of Sciences, Nanchang Road 509, Lanzhou 730000 (China); Gao, Q.X. [Institute of Cell Biology, School of Life Science, Lanzhou University, Southern Tianshui Road 222, Lanzhou 730000 (China)

    2006-03-15

    The effects of 960 MeV carbon ion beam and 8 MeV X-ray irradiation on adventitious shoots from in vitro leaf explants of two different Saintpaulia ionahta (Mauve and Indikon) cultivars were studied with regard to tissue increase, shoots differentiation and morphology changes in the shoots. The experimental results showed that the survival fraction of shoot formation for the Mauve and Indikon irradiated with the carbon ion beam at 20 Gy were 0.715 and 0.600, respectively, while those for both the cultivars exposed to the X-ray irradiation at the same dose were 1.000. Relative biological effectiveness (RBE) of Mauve with respect to X-ray was about two. Secondly, the percentage of regenerating explants with malformed shoots in all Mauve regenerating explants irradiated with carbon ion beam at 20 Gy accounted for 49.6%, while that irradiated with the same dose of X-ray irradiation was only 4.7%; as for Saintpaulia ionahta Indikon irradiated with 20 Gy carbon ion beam, the percentage was 43.3%, which was higher than that of X-ray irradiation. Last, many chlorophyll deficient and other varieties of mutants were obtained in this study. Based on the results above, it can be concluded that the effect of mutation induction by carbon ion beam irradiation on the leaf explants of Saintpaulia ionahta is better than that by X-ray irradiation; and the optimal mutagenic dose varies from 20 Gy to 25 Gy for carbon ion beam irradiation.

  7. Effects of ion beam irradiation on adventitious shoot regeneration from in vitro leaf explants of Saintpaulia ionahta

    Science.gov (United States)

    Zhou, L. B.; Li, W. J.; Ma, S.; Dong, X. C.; Yu, L. X.; Li, Q.; Zhou, G. M.; Gao, Q. X.

    2006-03-01

    The effects of 960 MeV carbon ion beam and 8 MeV X-ray irradiation on adventitious shoots from in vitro leaf explants of two different Saintpaulia ionahta (Mauve and Indikon) cultivars were studied with regard to tissue increase, shoots differentiation and morphology changes in the shoots. The experimental results showed that the survival fraction of shoot formation for the Mauve and Indikon irradiated with the carbon ion beam at 20 Gy were 0.715 and 0.600, respectively, while those for both the cultivars exposed to the X-ray irradiation at the same dose were 1.000. Relative biological effectiveness (RBE) of Mauve with respect to X-ray was about two. Secondly, the percentage of regenerating explants with malformed shoots in all Mauve regenerating explants irradiated with carbon ion beam at 20 Gy accounted for 49.6%, while that irradiated with the same dose of X-ray irradiation was only 4.7%; as for Saintpaulia ionahta Indikon irradiated with 20 Gy carbon ion beam, the percentage was 43.3%, which was higher than that of X-ray irradiation. Last, many chlorophyll deficient and other varieties of mutants were obtained in this study. Based on the results above, it can be concluded that the effect of mutation induction by carbon ion beam irradiation on the leaf explants of Saintpaulia ionahta is better than that by X-ray irradiation; and the optimal mutagenic dose varies from 20 Gy to 25 Gy for carbon ion beam irradiation.

  8. In vtro adventitious shoot regeneration from cotyledon explant of brassica oleracea subsp. Italica and brassica oleracea subsp. capitata using tdz and naa

    International Nuclear Information System (INIS)

    Broccoli(Brassica oleracea subsp. italica) cv. Green Dragon King and cabbage (Brassica oleracea subsp. capitata) cv. Gianty are important vegetable crops grown in Cameron Highlands, Malaysia. The cotyledons of both cultivars were used as explant source for in vitro shoot regeneration. The objective of this research was to examine the influence of the growth regulators thidiazuron (TDZ) and naphthaleneacetic acid (NAA) on adventitious shoot formation in these cultivars. This system of adventitious shoot regeneration from cotyledon explants could be useful as a tool for genetic transformation of the subspecies. Cotyledon explants of both cultivars excised from 5-day-old in vitro germinated seedlings were placed on shoot induction medium containing basal salts of Murashige and Skoog (MS) and various concentrations of TDZ and NAA. The highest percentage of cotyledon explant of broccoli cv. Green Dragon King producing shoot (76.66%) and the highest mean number of shoots produced per explant (0.9) were obtained on 0.1 mg/l TDZ with 0.1 mg/l NAA. Meanwhile, the highest percentage of cotyledon explant of cabbage cv. Gianty producing shoots (86.67%) and highest number of shoots produced per explant (1.1) were recorded on 0.5 mg/l TDZ with 0.1 mg/l NAA. Therefore, 0.1 mg/l TDZ with 0.1 mg/l NAA and 0.5 mg/l TDZ with 0.1mg/l NAA are the recommended combinations for adventitious shoot regeneration from cotyledonary explants of broccoli cv. Dragon King and cabbage cv. Gianty respectively. (author)

  9. Adventitious Shoot Organogenesis and Plant Regeneration from Cotyledons of Diploid Diyarbakır Watermelon (Citrullus lanatus cv. "Sürme")

    OpenAIRE

    PİRİNÇ, Vedat

    2003-01-01

    Adventitious shoots were obtained from the diploid Diyarbakır watermelon cultivar "Sürme" by culturing cotyledons on shoot regeneration medium for 3 weeks. The effects of two cytokinins, benzyl amino purine (BA) and kinetine (Kin), on shoot organogenesis were examined. The number of shoots per explant were approximately more than 50% higher when 0.5 mg/l BA was used compared to the most effective kinetin concentration (1 mg/l). Plants were obtained by transferring 1 to 2 cm shoots t...

  10. Methyl Jasmonate and Salicylic Acid Induced Oxidative Stress and Accumulation of Phenolics in Panax ginseng Bioreactor Root Suspension Cultures

    Directory of Open Access Journals (Sweden)

    Kee-Yoeup Paek

    2007-03-01

    Full Text Available To investigate the enzyme variations responsible for the synthesis of phenolics, 40 day-old adventitious roots of Panax ginseng were treated with 200 μM methyl jasmonate (MJ or salicylic acid (SA in a 5 L bioreactor suspension culture (working volume 4 L. Both treatments caused an increase in the carbonyl and hydrogen peroxide (H2O2 contents, although the levels were lower in SA treated roots. Total phenolic, flavonoid, ascorbic acid, non-protein thiol (NPSH and cysteine contents and 1,1-diphenyl-2-picrylhydrazyl (DPPH radical reducing activity were increased by MJ and SA. Fresh weight (FW and dry weight (DW decreased significantly after 9 days of exposure to SA and MJ. The highest total phenolics (62%, DPPH activity (40%, flavonoids (88%, ascorbic acid (55%, NPSH (33%, and cysteine (62% contents compared to control were obtained after 9 days in SA treated roots. The activities of glucose 6-phosphate dehydrogenase, phenylalanine ammonia lyase, substrate specific peroxidases (caffeic acid peroxidase, quercetin peroxidase and ferulic acid peroxidase were higher in MJ treated roots than the SA treated ones. Increased shikimate dehydrogenase, chlorogenic acid peroxidase and β-glucosidase activities and proline content were observed in SA treated roots than in MJ ones. Cinnamyl alcohol dehydrogenase activity remained unaffected by both MJ and SA. These results strongly indicate that MJ and SA induce the accumulation of phenolic compounds in ginseng root by altering the phenolic synthesis enzymes.

  11. Effect of Polar Auxin Transport on Rice Root Development%生长素极性运输在水稻根发育中的作用

    Institute of Scientific and Technical Information of China (English)

    周大喜; 殷珂; 许智宏; 薛红卫

    2003-01-01

    Polar auxin transport (PAT) is critical in plant growth and development, especially polardifferentiation and pattern formation. Lots of studies have been performed in dicots while relative less inmonocots. Using two kinds of PAT inhibitors, 2, 3, 5-triiodobenzoic acid (TIBA) and 9-hydroxyfluorene-9-carboxylic acid (HFCA), it was shown that PAT is important for rice (Oryza sativa L cv. Zhonghua 11) rootdevelopment, including elongation of the primary roots, initiation and elongation of lateral roots, andformation of adventitious roots. Inhibition of PAT resulted in the shortened primary roots, less and short-ened lateral and adventitious roots. Exogenously supplemented NAA can partially rescue the formation ofadventitious roots but not lateral roots, while low concentration of NAA (0.1 μmol/L) could not rescueeither of them, suggesting the possible different mechanisms of lateral and adventitious root initiations.Treatment of 30 μrnol/L TIBA did not completely inhibit the initiation of lateral roots, and survival capaci-ties of which were demonstrated through cross section experiments revealing the presence of primordialof lateral roots at different stages. Further studies through localized application of PAT inhibitors indicatedthat auxin flow, transported from coleoptiles to the base, is not only responsible for the auxin contents instem nodes but also critical for initiation and elongation of adventitious roots.%生长素极性运输(PAT)在植物生长发育尤其是极性发育和模式建成中起重要作用.采用2种PAT抑制剂TIBA(2,3,5-triiodobenzoic acid)和HFCA(9-hydroxyfluorene-9-carboxylic acid)处理水稻(Oryza sativa L. cv.Zhonghua)幼苗,结果表明:PAT影响水稻根发育包括主根的伸长、侧根的起始和伸长以及不定根的发育.PAT的抑制导致主根变短、侧根和不定根数目减少.外源附加生长素(NAA)可以部分恢复不定根的形成但不能恢复侧根的形成,表明在侧根和不定根的形成上可

  12. Leaf presence and indolebutyric acid on cuttings rooting of dragon tree

    Directory of Open Access Journals (Sweden)

    Carlos André Stuepp

    2015-07-01

    Full Text Available Paulownia fortunei (Scrophulariaceae, native to East Asia, has a wide geographical distribution. In this work was studied the rooting of Paulownia fortunei cuttings, with and without leaves, collected in three seasons and treated with the application of indolebutyric acid (IBA. Cuttings were also compared for possible anatomical differences between seasons. Originated from current year shoots in autumn/2011, spring/2011 and summer/2012, two types of cuttings were prepared : one about 10-12 cm long, with bevel cut on the base and straight at the apex, with two leaves reduced to an area of 78.5 cm²; the other with the same specifications, with leaves completely removed. After disinfection, base of the cuttings was treated with IBA (0, 500, 1.000, 1.500 and 2.000 mg L-1. Planting was made in tubes of 110 cm³, with medium size vermiculite particles and carbonized rice hull (1:1 and installed in a greenhouse with intermittent mist. After 60 days it was verified that the absence of leaves favored the adventitious rooting in all the seasons, with the highest rooting percentage in autumn (12.75%. The application of IBA did not have influence on rooting of any type of cuttings. No anatomical differences were observed between the bases of cuttings collected in the studied seasons.

  13. Root Graded Lie Superalgebras

    OpenAIRE

    Yousofzadeh, Malihe

    2015-01-01

    We define root graded Lie superalgebras and study their connection with centerless cores of extended affine Lie superalgebras; our definition generalizes the known notions of root graded Lie superalgebras.

  14. Using Square Roots

    Science.gov (United States)

    Wilson, William Wynne

    1976-01-01

    This article describes techniques which enable the user of a comparatively simple calculator to perform calculations of cube roots, nth roots, trigonometric, and inverse trigonometric functions, logarithms, and exponentials. (DT)

  15. WHY ROOTING FAILS.

    Energy Technology Data Exchange (ETDEWEB)

    CREUTZ,M.

    2007-07-30

    I explore the origins of the unphysical predictions from rooted staggered fermion algorithms. Before rooting, the exact chiral symmetry of staggered fermions is a flavored symmetry among the four 'tastes.' The rooting procedure averages over tastes of different chiralities. This averaging forbids the appearance of the correct 't Hooft vertex for the target theory.

  16. The Root Canal Biofilm

    NARCIS (Netherlands)

    Sluis, van der L.W.M.; Boutsioukis, C.; Jiang, L.M.; Macedo, R.; Verhaagen, B.; Versluis, M.; Chávez de Paz, E.; Sedgley, C.M.; Kishen, A.

    2015-01-01

    The aims of root canal irrigation are the chemical dissolution or disruption and the mechanical detachment of pulp tissue, dentin debris and smear layer (instrumentation products), microorganisms (planktonic or biofilm), and their products from the root canal wall, their removal out of the root cana

  17. Root canal irrigation

    NARCIS (Netherlands)

    L. van der Sluis; C. Boutsioukis; L.M. Jiang; R. Macedo; B. Verhaagen; M. Versluis

    2015-01-01

    The aims of root canal irrigation are the chemical dissolution or disruption and the mechanical detachment of pulp tissue, dentin debris and smear layer (instrumentation products), microorganisms (planktonic or biofilm), and their products from the root canal wall, their removal out of the root cana

  18. 葡萄糖在锌诱导水稻根系生长中的作用%Effect of Glucose on Zinc-induced Growth of Root System in Rice

    Institute of Scientific and Technical Information of China (English)

    陈振华; 冯婷婷; 刘乐雨; 徐小利; 蔡凤香; 冯永永; 赵凤云

    2011-01-01

    [目的]本实验旨在以水稻为材料研究葡萄糖信号在锌诱导根系生长中的作用。[方法]本实验以水稻中花11号为材料,分析了在不同浓度的葡萄糖、葡萄糖+锌、甘露醇和锌+甘露醇处理条件下,水稻的根系生长、活性氧的产生和根系质子分泌的变化。[结果]结果表明,在有锌和无锌的处理条件下,除了不定根数和不定根侧根数外,株高、初生根长、初生根侧根数/长、不定根长和不定根侧根长均不同程度地受到糖浓度的影响,高浓度糖诱导活性氧产生,缺糖则导致根系的质子分泌能力降低。但是在相同浓度的糖处理条件下,锌诱导这些指标的变化与无锌处理的结果明显不同。相同浓度的葡萄糖和甘露醇对根系生长的影响有显著差异,说明这种变化是由糖信号而非渗透势引起的。[结论]这些结果表明,在正常和锌处理条件下葡萄糖对水稻根系的生长都具有重要的调节作用。%[Objective] This study was aimed at exploring the effect of glucose signal on the zinc-induced growth of root system using rice as the material.[Method] The variation of root system growth,active oxygen production and proton secretion of root systems treated with various concentrations of glucose,glucose + Zn(NO3)2,mannitol and Zn(NO3)2 + mannitol were analyzed in rice(Oryza sativa L.cv Zhonghua no.11).[Result] The results showed that the concentrations of glucose had affected the shoot height,primary root length,amount and length of lateral roots on primary roots,adventitious root length and length of lateral roots on adventitious roots in varying degrees,but not the amount of adventitious roots and lateral roots on adventitious roots under Zn+ and Zn-condition.Glucose of high concentrations induced the production of active oxygen,while lacking of glucose would lead to the decrease of proton secretion of root systems.However,there were significant differences

  19. Effect of Iron Plaque on Root Growth and Activity of Two Wetland Plants%根表铁膜对2种景观湿地植物根系发育及活力的影响

    Institute of Scientific and Technical Information of China (English)

    钟顺清

    2015-01-01

    Root activity is an important indicator of plant response to environmental conditions.High iron content (Fe-plaques)frequently form on roots of wetland plants,reflecting the adaptation of wetland plants to submersion, facilitates nutrient uptake and prevents uptake of phytotoxins.In this study,root activity and the growth of adventi-tious roots of Typha latifolia and Iris pseudacorus in solution culture experiments were determined to investigate the response of wetland plant roots to iron plaque induced on the root surface.Typha latifolia and Iris pseudacorus (each 60 plants)were cultivated in Hoagland nutrient solution for one week.After adventitious roots of Typha lati-folia and Iris pseudacorus emerged,the existing root was removed and the plants were cultivated in the Hoagland so-lution for an additional three weeks at a pH of 5 .5 .Thirty-five plants with similar shoot height and root length were transferred to seven plastic buckets with a solution pH of 5.0 and different Fe2+(FeSO4·7H2O)concentrations (0,10,20,60,100,150,200 mg/L)to induce iron plague formation.The buckets were covered with black po-lyethylene bags and filled with N2 gas.After five days,two plants were removed from solution to determine root ac-tivity.One week later,the fresh weight and activity of the adventitious roots of both species in all treatment groups were measured.Adventitious root growth of Typha latifolia was inhibited by Fe2+concentrations of less than 100 mg/L,but was promoted at concentrations over 100 mg/L.At higher Fe2+concentrations,the root activity of Typha latifolia decreased and there was a large difference [9.70 μg/(g·h)]between maximum and minimum values.However,the influence of Fe plague on the adventitious root growth of Iris pseudacorus was not significant in all treatments,and the root activity of Iris pseudacorus ranged from 2.36 μg/(g·h)to 5.48 μg/(g·h)with little variation among treatments.There was a significant negative relationship between the root

  20. 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 ...

  1. Root canal irrigants

    Directory of Open Access Journals (Sweden)

    Kandaswamy Deivanayagam

    2010-01-01

    Full Text Available Successful root canal therapy relies on the combination of proper instrumentation, irrigation, and obturation of the root canal. Of these three essential steps of root canal therapy, irrigation of the root canal is the most important determinant in the healing of the periapical tissues. The primary endodontic treatment goal must thus be to optimize root canal disinfection and to prevent reinfection. In this review of the literature, various irrigants and the interactions between irrigants are discussed. We performed a Medline search for English-language papers published untill July 2010. The keywords used were ′root canal irrigants′ and ′endodontic irrigants.′ The reference lists of each article were manually checked for additional articles of relevance.

  2. Roots and routes

    DEFF Research Database (Denmark)

    Christensen, Ann-Dorte; Jensen, Sune Qvotrup

    2011-01-01

    arguing that there is a dynamic interplay between roots and routes in people's lives. The empirical point of departure is narratives about roots and routes by ethnic minorities settled in Aalborg East, an underprivileged neighbourhood in northern Denmark. One of the main findings is a gap between the...... somewhat paradoxical finding is that it appears to be more difficult for transnational migrants to maintain their roots in the country of origin when they go back than it was to establish new roots in the host country...

  3. Roots of Dehn twists

    OpenAIRE

    McCullough, Darryl; Rajeevsarathy, Kashyap

    2009-01-01

    D. Margalit and S. Schleimer found examples of roots of the Dehn twist about a nonseparating curve in a closed orientable surface, that is, homeomorphisms whose nth power is isotopic to the Dehn twist. Our main theorem gives elementary number-theoretic conditions that describe the values of n for which an nth root exists, given the genus of the surface. Among its applications, we show that n must be odd, that the Margalit-Schleimer roots achieve the maximum value of n among the roots for a gi...

  4. Economic strategies of plant absorptive roots vary with root diameter

    Science.gov (United States)

    Kong, D. L.; Wang, J. J.; Kardol, P.; Wu, H. F.; Zeng, H.; Deng, X. B.; Deng, Y.

    2016-01-01

    Plant roots typically vary along a dominant ecological axis, the root economics spectrum, depicting a tradeoff between resource acquisition and conservation. For absorptive roots, which are mainly responsible for resource acquisition, we hypothesized that root economic strategies differ with increasing root diameter. To test this hypothesis, we used seven plant species (a fern, a conifer, and five angiosperms from south China) for which we separated absorptive roots into two categories: thin roots (thickness of root cortex plus epidermis perspective on our understanding of the root economics spectrum.

  5. 甜菜幼苗的分区及其肥大直根的定位研究%Zonation of Seedling of Beta vulgaris and Its Location of Fleshy Tap Root

    Institute of Scientific and Technical Information of China (English)

    林金科; 赖明志

    2000-01-01

    本文按照子叶节区理论(Cotyledon node zone theory)研究结果表明,甜菜幼苗的子叶节区类型为顶枝伸长型(Telome elongation type)。甜菜肥大直根采用幼苗分区定位法明确其根头部由上胚轴苗区发育而成;根颈部与根体是由长的顶枝伸长型的子叶节区发育而来;至于下面短的根尾,是下胚轴发育的产物;甜菜真正的根并不肥大。本研究证明甜菜肥大的部位(根体)是由子叶节区发生的,所以根体两侧分布的根既不是由主根上发出的侧根,也不是随处可生的不定根,乃系只有在特定部位生长的拟不定根。%The traditional zonation method and terminology of plant seedlings based on traditional morphological and anatomical theories and methods were challenged by the newly developed cotyledon node zone(CNZ) theory. Using sugar heat (Beta vulgaris) as material, it was found that its seedling belongs to the Telome elongation type..The fleshy, formerly called "tap root" comes actually from different zones on parts of the embryo. Thus, the head of the tap root was developed from the epicotyl shoot zone; the crown and body from the long CNZ and the short tail from hypocotyl. Consequently, the roots around the body of the "tap root" are neither tateral roots, nor adventitious, they should be called pseudo-adventitious roots.

  6. Chromatic roots and hamiltonian paths

    DEFF Research Database (Denmark)

    Thomassen, Carsten

    2000-01-01

    We present a new connection between colorings and hamiltonian paths: If the chromatic polynomial of a graph has a noninteger root less than or equal to t(n) = 2/3 + 1/3 (3)root (26 + 6 root (33)) + 1/3 (3)root (26 - 6 root (33)) = 1.29559.... then the graph has no hamiltonian path. This result is...

  7. Study on Rooting in vitro shoots of the Sophora japonica L%国槐组织培养生根的研究

    Institute of Scientific and Technical Information of China (English)

    刘桂民; 燕丽萍; 尹国良; 李自成; 刘翠兰; 孙超; 夏阳

    2012-01-01

    通过不同基本培养基、植物生长调节剂IAA、NAA、IBA和活性炭等对国槐试管苗不定根的诱导进行了系统研究。筛选出国槐最佳生根培养基是1/2MS+IAAO.5mg/L+蔗糖2%+琼脂0.65%,生根率达86%以上;并对不同苗龄试管苗不定根的发育过程进行了研究,结果表明,苗龄为20~25天的试管苗生根率最高可迭90%,而且生根周期较短。%The effect of the different basic medium, IAA,NAA,IBA and active carbon on rooting of shoots in test tubes of the Sophora japonica L was studied , The optimal medium of rooting is 1/2MS@ IAA 0.5mg/L @sucrose 2% fro @agar 0.65%, rooting ratio would reach 86%. The growth process of adventitious root in different seedling age was also studied,he result in dicated that the root rate of shoots in test tubes which the seedling age was 20%25day--long reached 90%, moreover the root cycle was short.

  8. Response to zinc deficiency of two rice lines with contrasting tolerance is determined by root growth maintenance and organic acid exudation rates, and not by zinc-transporter activity.

    Science.gov (United States)

    Widodo, Basuki; Broadley, Martin R; Rose, Terry; Frei, Michael; Pariasca-Tanaka, Juan; Yoshihashi, Tadashi; Thomson, Michael; Hammond, John P; Aprile, Alessio; Close, Timothy J; Ismail, Abdelbagi M; Wissuwa, Matthias

    2010-04-01

    *Zinc (Zn)-deficient soils constrain rice (Oryza sativa) production and cause Zn malnutrition. The identification of Zn-deficiency-tolerant rice lines indicates that breeding might overcome these constraints. Here, we seek to identify processes underlying Zn-deficiency tolerance in rice at the physiological and transcriptional levels. *A Zn-deficiency-tolerant line RIL46 acquires Zn more efficiently and produces more biomass than its nontolerant maternal line (IR74) at low [Zn](ext) under field conditions. We tested if this was the result of increased expression of Zn(2+) transporters; increased root exudation of deoxymugineic acid (DMA) or low-molecular-weight organic acids (LMWOAs); and/or increased root production. Experiments were performed in field and controlled environment conditions. *There was little genotypic variation in transcript abundance of Zn-responsive root Zn(2+)-transporters between the RIL46 and IR74. However, root exudation of DMA and LMWOA was greater in RIL46, coinciding with increased root expression of putative ligand-efflux genes. Adventitious root production was maintained in RIL46 at low [Zn](ext), correlating with altered expression of root-specific auxin-responsive genes. *Zinc-deficiency tolerance in RIL46 is most likely the result of maintenance of root growth, increased efflux of Zn ligands, and increased uptake of Zn-ligand complexes at low [Zn](ext); these traits are potential breeding targets. PMID:20100202

  9. ROOT User Workshop 2013

    CERN Document Server

    2013-01-01

    Since almost two decades, ROOT has established itself as the framework for HENP data processing and analysis. The LHC upgrade program and the new experiments being designed at CERN and elsewhere will pose even more formidable challenges in terms of data complexity and size. The new parallel and heterogeneous computing architectures that are either announced or already available will call for a deep rethinking of the code and the data structures to be exploited efficiently. This workshop, following from a successful series of such events, will allow you to learn in detail about the new ROOT 6 and will help shape the future evolution of ROOT.

  10. Quantitative measurements of root water uptake and root hydraulic conductivities

    Science.gov (United States)

    Zarebanadkouki, Mohsen; Javaux, Mathieu; Meunier, Felicien; Couvreur, Valentin; Carminati, Andrea

    2016-04-01

    How is root water uptake distributed along the root system and what root properties control this distribution? Here we present a method to: 1) measure root water uptake and 2) inversely estimate the root hydraulic conductivities. The experimental method consists in using neutron radiography to trace deuterated water (D2O) in soil and roots. The method was applied to lupines grown aluminium containers filled with a sandy soil. When the lupines were 4 weeks old, D2O was locally injected in a selected soil regions and its transport was monitored in soil and roots using time-series neutron radiography. By image processing, we quantified the concentration of D2O in soil and roots. We simulated the transport of D2O into roots using a diffusion-convection numerical model. The diffusivity of the roots tissue was inversely estimated by simulating the transport of D2O into the roots during night. The convective fluxes (i.e. root water uptake) were inversely estimating by fitting the experiments during day, when plants were transpiring, and assuming that root diffusivity did not change. The results showed that root water uptake was not uniform along the roots. Water uptake was higher at the proximal parts of the lateral roots and it decreased by a factor of 10 towards the distal parts. We used the data of water fluxes to inversely estimate the profile of hydraulic conductivities along the roots of transpiring plants growing in soil. The water fluxes in the lupine roots were simulated using the Hydraulic Tree Model by Doussan et al. (1998). The fitting parameters to be adjusted were the radial and axial hydraulic conductivities of the roots. The results showed that by using the root architectural model of Doussan et al. (1998) and detailed information of water fluxes into different root segments we could estimate the profile of hydraulic conductivities along the roots. We also found that: 1) in a tap-rooted plant like lupine water is mostly taken up by lateral roots; (2) water

  11. Regulation of Sucrose and Zinc on Root System Growth in Rice%蔗糖和锌对水稻根系生长的调节

    Institute of Scientific and Technical Information of China (English)

    张承仁; 徐小利; 冯永永; 刘乐雨; 冯婷婷; 陈振华; 蔡凤香; 赵凤云

    2012-01-01

    [Objective] The aim was to study the relationship between urcrose, zinc and the root system growth in rice. [Method] Changes of root system growth, ROS generation and root system proton export ability were analyzed in rice (Oryza sativa L. cv Zhonghua No.11) treated with different concentrations of Zn (NO3)3 sucrose, com- bined sucrose and Zn (NO3)3 mannitol as well as mannitol plus Zn (NO3)2. [Result] The results showed that treatment with 1-3 mM Zn(NO3)2 resulted in significant increases in total root length /number and in accumulation of H202 and 02- but decreases in root system proton export ability. With the exception of shoot length, the length of primary, adventitious, and lateral roots, and the number of adventitious, and lateral roots on primary /adventitious roots were all influenced by different concentrations of sucrose. High concentrations of sucrose caused increases in H202 and O2-, starva- tion or high concentrations of sucrose reduced root system proton export ability after treating with or without Zn. However, at the same concentration of sucrose, different changes of these indicators were observed between Zn and non-Zn treatments. The regulation of root system growth induced by sucrose was marked different from that of mannitol at the same concentration of 5%, suggesting that these effects were caused by sugar signal but not by osmotic potential. [Conclusion] This study indicat- ed that both sucrose and Zn play important roles in the regulation of rice root system growth.%【目的】研究锌和蔗糖与水稻根系生长发育的关系。【方法]以水稻中花11号为试验材料,分析了不同浓度的锌、蔗糖、甘露醇、锌+蔗糖和锌+甘露醇处理条件下水稻根系生长、活性氧产生和根系质子分泌的变化。[结果]在1~3mmol/L范围内随着锌浓度的增加,水稻根系总长度、数量及活性氧的产生均增加,但质子分泌水平降低。除了株高外,初生根

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

    Directory of Open Access Journals (Sweden)

    Kumar Ramesh R.

    2011-01-01

    Full Text Available 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 showed significant positive genotypic correlation with yield. Starch-fiber ratio (SFR, determinant of brittle root texture showed strong negative association with root yield. The total alkaloid content had positive genotypic correlation with root yield. So genetic upgradation should aim at optimum balance between two divergent groups of traits i.e. root yield traits (root morphometric traits and crude fiber content and root textural quality traits (starch content and SFR to develop superior genotypes with better yield and quality.

  13. 新疆两种纤维亚麻胚轴段高频萌芽诱导%High Frequency Adventitious Budding Induction from Hypocotyls Segments of Two Kinds of Fiber Flax in Xinjiang

    Institute of Scientific and Technical Information of China (English)

    邓倩; 刘静文; 王伟; 计巧灵

    2012-01-01

    [目的]通过建立新疆主栽的两个纤维亚麻品种(范妮和天鑫3号)高频率不定芽离体再生体系,为进一步筛选其体细胞耐盐突变体奠定基础.[方法]以不同消毒剂处理种子,以下胚轴段为外植体,运用不同植物生长调节剂组合诱导胚轴段再生不定芽.[结果]两种种子在10%的H2O2中处理10 min灭菌效果最好;范妮不定芽诱导最适宜培养基为:MS+ BA 0.45 mg/L+ IAA 0.3 mg/L,不定芽诱导率达180%;天鑫3号不定芽诱导最适培养基为:MS+ BA 0.6 mg/L+ NAA 0.03 mg/L,不定芽的诱导率达到98%.[结论]不同的亚麻品种在下胚轴萌芽过程中对植物生长调节剂的配比和浓度的要求也不尽相同,探明了范妮和天鑫3号高频不定芽发生的最佳植物生长调节剂的组合和浓度.%[Objective] The purpose of this study was to lay the foundation for further screening of somatic salt tolerant mutants through establishment of high frequency in vitro regeneration system of adventitious buds of two species of flax ( Fany and Tianxin 3 ) that are mainly planted in Xinjiang. [ Method ] The seeds were sterilized with different disinfectants. With hypocotylar segments of the seeding as explants, regenerated adventitious buds in segments were induced by different combination and concentration of plant growth regulators. [Result] Sterilizing effects were more suitable for the two kinds seeds treated with 10% H2O2 for 10 min. The optimum medium for inducing adventitious buds from Fany hypocotyls was MS + BA 0. 45 mg/L + IAA 0. 3 mg/L, induction rate of adventitious bud reached 180%. The optimum medium for inducing adventitious buds from Tianxin 3 hypocotyls was MS + BA 0. 6 mg/L + NAA 0. 03 mg/L, induction rate of adventitious bud reached 98% . [ Conclusion ] The results showed that different species of flax need different combination and concentration of plant growth regulators for inducing adventitious buds from hypocotyls, and the optimum combination

  14. Modeling root reinforcement using root-failure Weibull survival function

    Directory of Open Access Journals (Sweden)

    M. Schwarz

    2013-03-01

    Full Text Available Root networks contribute to slope stability through complicated interactions that include mechanical compression and tension. Due to the spatial heterogeneity of root distribution and the dynamic of root turnover, the quantification of root reinforcement on steep slope is challenging and consequently the calculation of slope stability as well. Although the considerable advances in root reinforcement modeling, some important aspect remain neglected. In this study we address in particular to the role of root strength variability on the mechanical behaviors of a root bundle. Many factors may contribute to the variability of root mechanical properties even considering a single class of diameter. This work presents a new approach for quantifying root reinforcement that considers the variability of mechanical properties of each root diameter class. Using the data of laboratory tensile tests and field pullout tests, we calibrate the parameters of the Weibull survival function to implement the variability of root strength in a numerical model for the calculation of root reinforcement (RBMw. The results show that, for both laboratory and field datasets, the parameters of the Weibull distribution may be considered constant with the exponent equal to 2 and the normalized failure displacement equal to 1. Moreover, the results show that the variability of root strength in each root diameter class has a major influence on the behavior of a root bundle with important implications when considering different approaches in slope stability calculation. Sensitivity analysis shows that the calibration of the tensile force and the elasticity of the roots are the most important equations, as well as the root distribution. The new model allows the characterization of root reinforcement in terms of maximum pullout force, stiffness, and energy. Moreover, it simplifies the implementation of root reinforcement in slope stability models. The realistic quantification of root

  15. The "Green" Root Beer Laboratory

    Science.gov (United States)

    Clary, Renee; Wandersee, James

    2010-01-01

    No, your students will not be drinking green root beer for St. Patrick's Day--this "green" root beer laboratory promotes environmental awareness in the science classroom, and provides a venue for some very sound science content! While many science classrooms incorporate root beer-brewing activities, the root beer lab presented in this article has…

  16. Root development under drought stress

    OpenAIRE

    Franco Leemhuis, José Antonio

    2011-01-01

    Serving as interfaces between plant and the soil, roots are much more exposed to drought stress than the upper plant parts. Therefore, the root system can be as affected, or even more affected, than the aerial parts of the plant for drought stress (Franco et al., 2011). Nevertheless, the influence of this stress on root activity and development has been much less studied. Undoubtedly, this is due to limitations on accessibility for root observations; being studies on root system dynamics espe...

  17. Updating of adventitious fuel pin failure frequency in sodium-cooled fast reactors and probabilistic risk assessment on consequent severe accident in Monju

    International Nuclear Information System (INIS)

    Experimental studies, deterministic approaches and probabilistic risk assessments (PRAs) on local fault (LF) propagation in sodium-cooled fast reactors (SFRs) have been performed in many countries because LFs have been historically considered as one of the possible causes of severe accidents. Adventitious-fuel-pin-failures (AFPFs) have been considered to be the most dominant initiators of LFs in these PRAs because of their high frequency of occurrence during reactor operation and possibility of fuel-element-failure-propagation (FEFP). A PRA on FEFP from AFPF (FEFPA) in the Japanese prototype SFR (Monju) was performed in this study based on the state-of-the-art knowledge, reflecting the most recent operation procedures under off-normal conditions. Frequency of occurrence of AFPF in SFRs which was the initiating event of the event tree in this PRA was updated using a variety of methods based on the above-mentioned latest review on experiences of this phenomenon. As a result, the frequency of occurrence of, and the core damage frequency (CDF) from, AFPF in Monju was significantly reduced to a negligible magnitude compared with those in the existing PRAs. It was, therefore concluded that the CDF of FEFPA in Monju could be comprised in that of anticipated transient without scram or protected loss of heat sink events from both the viewpoint of occurrence probability and consequences. (author)

  18. Study on Adventitious Music Elements in Wuhe Folksong%五河民歌中的外来音乐元素研究

    Institute of Scientific and Technical Information of China (English)

    王敬

    2015-01-01

    由于五河地处淮河中游,属南北过渡地带,以及战乱、灾害等产生的人口迁移,历史上五河出现了大量的移民,他们为五河民歌注入了新的音乐元素,拟从五河民歌词曲的大同小异、词同曲异、曲同词异三种情况对其中的外来音乐进行分析,凸显五河民歌南北兼容的过渡性音乐特点。%Wuhe is a place which lies in the middle stretches of the Huaihe River and in an intermediate region between the South and the North of China,historical turmoil of wars and natural disasters brought a considerable migrants here.They infused many new elements into the Wuhe folksong.By analyzing its ad-ventitious music from the three facts that its lyrics similar with melodies,same lyrics with different melo-dies and different lyrics with same melodies,it was well-established that Wuhe folksong are provided with the musical traits of transitional compatibilities of some other folksongs in Southern and Northern areas of China.

  19. PATTERN OF ROOTING AND GROWTH OF CUTTINGS OF SOME SPECIES OF INSECTICIDAL AND MEDICINAL IMPORTANCE AS AFFECTED BY GROWTH PROMOTING SUBSTANCES

    Directory of Open Access Journals (Sweden)

    Obi, E.A

    2013-06-01

    Full Text Available This study was designed to examine the effects of promoting substances on bud retention, rooting and plantlets survival of rooted cuttings on selected tree species using growth promoting substances. Stem cuttings were treated with rooting-promoting substances, planted in plastic pots filled with top soil and arranged using a completely randomized design (CRD in a screen house. Stem cuttings of pepper fruit, guava, bush mango and cashew were obtained from the Teaching and Research Farm, Federal University of Technology, Akure, Nigeria. The experiments were conducted in 2010. The effects of growth promoting substances namely indole-3-butyric acid (IBA, indole-3-acetic acid (IAA and 1-naphthalene acetic acid (NAA applied 50 µM concentration and coconut water (50% dilution were evaluated on adventitious root formation, shoot growth (bud retention and survival of plantlets of hard- to semi-hardwood cuttings of tested tree species. The effects of growth promoting substances were significant on emergence of plantlets (rooting, growth and survival of plantlets. Number of sprouts (plantlets produced were highest in guava and pepper fruit followed by bush mango and cashew. The cuttings from guava and pepper fruit treated with coconut water and NAA promoted the survival of plantlets. Coconut water and NAA were found better than IBA and IAA in terms of bud retention and rooting, leaf development and survival of plantlets. In most of the tested species, wilting of leaves commenced 6 weeks after planting (WAP and attained 100% mortality thereafter except for pepper fruit cuttings dipped in coconut water. The treatments modified the rooting response among species by promoting percentages of rooting, reduction in bud abscission and plantlet survival. The results affirmed the possibility of propagating plantlets from stem cuttings of the tested species using growth promoting substances.

  20. Identification of QTLs for root characteristics in maize grown in hydroponics and analysis of their overlap with QTLs for grain yield in the field at two water regimes.

    Science.gov (United States)

    Tuberosa, Roberto; Sanguineti, Maria Corinna; Landi, Pierangelo; Giuliani, Marcella Michela; Salvi, Silvio; Conti, Sergio

    2002-01-01

    We investigated the overlap among quantitative trait loci (QTLs) in maize for seminal root traits measured in hydroponics with QTLs for grain yield under well-watered (GY-WW) and water-stressed (GY-WS) field conditions as well as for a drought tolerance index (DTI) computed as GY-WS/GY-WW. In hydroponics, 11, 7, 9, and 10 QTLs were identified for primary root length (R1L), primary root diameter (R1D), primary root weight (R1W), and for the weight of the adventitious seminal roots (R2W), respectively. In the field, 7, 8, and 9 QTLs were identified for GY-WW, GY-WS, and DTI, respectively. Despite the weak correlation of root traits in hydroponics with GY-WW, GY-WS, and DTI, a noticeable overlap between the corresponding QTLs was observed. QTLs for R2W most frequently and consistently overlapped with QTLs for GY-WW, GY-WS, and/or DTI. At four QTL regions, an increase in R2W was positively associated with GY-WW, GY-WS, and/or DTI. A 10 cM interval on chromosome 1 between PGAMCTA205 and php20644 showed the strongest effect on R1L, R1D, R2W, GY-WW, GY-WS, and DTI. These results indicate the feasibility of using hydroponics in maize to identify QTL regions controlling root traits at an early growth stage and also influencing GY in the field. A comparative analysis of the QTL regions herein identified with those described in previous studies investigating root traits in different maize populations revealed a number of QTLs in common.

  1. Variation in root wood anatomy

    NARCIS (Netherlands)

    Cutler, D.F.

    1976-01-01

    Variability in the anatomy of root wood of selected specimens particularly Fraxinus excelsior L. and Acer pseudoplatanus L. in the Kew reference microscope slide collection is discussed in relation to generalised statements in the literature on root wood anatomy.

  2. Advances in root reinforcement experiments

    Science.gov (United States)

    Giadrossich, Filippo; Schwarz, Massimiliano; Niedda, Marcello

    2013-04-01

    Root reinforcement is considered in many situations an important effect of vegetation for slope stability. In the past 20 years many studies analyzed root reinforcement in laboratory and field experiments, as well as through modeling frameworks. Nearby the important contribution of roots to shear strength, roots are recognized to impart stabilization also through lateral (parallel to slope) redistribution of forces under tension. Lateral root reinforcement under tensile solicitations (such as in the upper part of a shallow landslide) was documented and discussed by some studies. The most common method adopted to measure lateral root reinforcement are pullout tests where roots (single or as bundle) are pulled out from a soil matrix. These conditions are indeed representative for the case where roots within the mass of a landslide slip out from the upper stable part of the slope (such in a tension crack). However, there is also the situation where roots anchored at the upper stable part of the slope slip out from the sliding soil mass. In this last case it is difficult to quantify root reinforcement and no study discussed this mechanism so far. The main objective of this study is to quantify the contribution of roots considering the two presented cases of lateral root reinforcement discussed above - roots slipping out from stable soil profile or sliding soil matrix from anchored roots-, and discuss the implication of the results for slope stability modeling. We carried out a series of laboratory experiments for both roots pullout and soil sliding mechanisms using a tilting box with a bundle of 15 roots. Both Douglas (Pseudotsuga menziesii) roots and soil were collected from the study area in Sardinia (Italy), and reconstructed in laboratory, filling the root and soil layer by layer up to 0.4 meter thickness. The results show that the ratio between pullout force and force transferred to the root during soil sliding range from 0.5 to 1. This results indicate that

  3. The Gaudi Framework and ROOT

    CERN Document Server

    Couturier, B; Clemencic, M

    2013-01-01

    The Gaudi framework, at the core of LHCb applications, relies on many features of ROOT, from the Mathematical libraries, to the tools for reflection and persistency. While Gaudi's architecture is under review in order to fulfill the LHCb computing requirements after LS1 and upgrade, significant changes are also announced for ROOT 6. This talk will review the usage of ROOT within Gaudi and LHCb applications, in order to present the features needed by LHCb to migrate to the new ROOT.

  4. Root canal retained restorations: 3. Root-face attachments.

    Science.gov (United States)

    Dummer, P M; Edmunds, D H; Gidden, J R

    1990-10-01

    It has been common practice for many years to use retained roots to provide support and stability for partial or full dentures. The retention of such overdentures is greatly enhanced if the remaining roots are modified and restored with posts and root-face attachments. The final article in this series on root canal retained restorations classifies and describes some of the root-face attachments currently available, and also describes a number of prefabricated post systems with integral overdenture attachments. Guidelines for clinical and laboratory procedures are given. PMID:2097234

  5. Negative phototropism of rice root

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@It is often believed that the stem of higher plants has characteristics of positive phototropism, and the root shows no phototropism or no sensitivity to light though the root of Arabdopsis was reported possessing characteristics of negative phototropism. In this study, a distinct negative phototropism of the root system of rice seedlings was observed.

  6. Diagravitropism in corn roots

    Science.gov (United States)

    Leopold, A. C.; Wettlaufer, S. H.

    1988-01-01

    The diagravitropic behavior of Merit corn (Zea mays L.) roots grown in darkness provides an opportunity for comparison of two qualitatively different gravitropic systems. As with positive gravitropism, diagravitropism is shown to require the presence of the root cap, have a similar time course for the onset of curvature, and a similar presentation time. In contrast with positive gravitropism, diagravitropism appears to have a more limited requirement for calcium, for it is insensitive to the elution of calcium by EGTA and insensitive to the subsequent addition of a calcium/EGTA complex. These results are interpreted as indicating that whereas the same sensing system is shared by the two types of gravitropism, separate transductive systems are involved, one for diagravitropism, which is relatively independent of calcium, and one for positive gravitropism, which is markedly dependent on calcium.

  7. Roots of Financial Literacy

    OpenAIRE

    Grohmann, Antonia; Kouwenberg, Roy; Menkhoff, Lukas

    2014-01-01

    Our study aims to uncover the roots of financial literacy. Better financial literacy predicts more informed savings and borrowing decisions in our sample, covering the urban middle-class in an emerging economy. We then test education at school, family background, parental teaching, and childhood experiences with money as potential determinants of financial literacy. In addition to risk tolerance and having basic numeracy skills, we find that family variables matter most, in particular better ...

  8. Mental Roots of Terror

    OpenAIRE

    Saruhan, Müfit Selim

    2004-01-01

    In this article, I deal with mental and terror relationship. Mental roots of terror are being examined. Religion has nothing to do with terrorism. Terrorist tries to misuse religion. Mental with prejudice and lack of knowledge occupies the personality of individual and his ability to judge. Purification of mind from any external and internal prejudices is the unique solution of terrorism. Only within extensive education we can overcome terrorism. Terrorism could not apply to a religion or a n...

  9. Design, fabrication and perivascular implantation of bioactive scaffolds engineered with human adventitial progenitor cells for stimulation of arteriogenesis in peripheral ischemia.

    Science.gov (United States)

    Carrabba, M; De Maria, C; Oikawa, A; Reni, C; Rodriguez-Arabaolaza, I; Spencer, H; Slater, S; Avolio, E; Dang, Z; Spinetti, G; Madeddu, P; Vozzi, G

    2016-03-01

    Cell therapy represents a promising option for revascularization of ischemic tissues. However, injection of dispersed cells is not optimal to ensure precise homing into the recipient's vasculature. Implantation of cell-engineered scaffolds around the occluded artery may obviate these limitations. Here, we employed the synthetic polymer polycaprolactone for fabrication of 3D woodpile- or channel-shaped scaffolds by a computer-assisted writing system (pressure assisted micro-syringe square), followed by deposition of gelatin (GL) nanofibers by electro-spinning. Scaffolds were then cross-linked with natural (genipin, GP) or synthetic (3-glycidyloxy-propyl-trimethoxy-silane, GPTMS) agents to improve mechanical properties and durability in vivo. The composite scaffolds were next fixed by crown inserts in each well of a multi-well plate and seeded with adventitial progenitor cells (APCs, 3 cell lines in duplicate), which were isolated/expanded from human saphenous vein surgical leftovers. Cell density, alignment, proliferation and viability were assessed 1 week later. Data from in vitro assays showed channel-shaped/GPTMS-crosslinked scaffolds confer APCs with best alignment and survival/growth characteristics. Based on these results, channel-shaped/GPTMS-crosslinked scaffolds with or without APCs were implanted around the femoral artery of mice with unilateral limb ischemia. Perivascular implantation of scaffolds accelerated limb blood flow recovery, as assessed by laser Doppler or fluorescent microspheres, and increased arterial collaterals around the femoral artery and in limb muscles compared with non-implanted controls. Blood flow recovery and perivascular arteriogenesis were additionally incremented by APC-engineered scaffolds. In conclusion, perivascular application of human APC-engineered scaffolds may represent a novel option for targeted delivery of therapeutic cells in patients with critical limb ischemia.

  10. Inhibition of fucosylation of cell wall components by 2-fluoro 2-deoxy-L-fucose induces defects in root cell elongation.

    Science.gov (United States)

    Dumont, Marie; Lehner, Arnaud; Bardor, Muriel; Burel, Carole; Vauzeilles, Boris; Lerouxel, Olivier; Anderson, Charles T; Mollet, Jean-Claude; Lerouge, Patrice

    2015-12-01

    Screening of commercially available fluoro monosaccharides as putative growth inhibitors in Arabidopsis thaliana revealed that 2-fluoro 2-l-fucose (2F-Fuc) reduces root growth at micromolar concentrations. The inability of 2F-Fuc to affect an Atfkgp mutant that is defective in the fucose salvage pathway indicates that 2F-Fuc must be converted to its cognate GDP nucleotide sugar in order to inhibit root growth. Chemical analysis of cell wall polysaccharides and glycoproteins demonstrated that fucosylation of xyloglucans and of N-linked glycans is fully inhibited by 10 μm 2F-Fuc in Arabidopsis seedling roots, but genetic evidence indicates that these alterations are not responsible for the inhibition of root development by 2F-Fuc. Inhibition of fucosylation of cell wall polysaccharides also affected pectic rhamnogalacturonan-II (RG-II). At low concentrations, 2F-Fuc induced a decrease in RG-II dimerization. Both RG-II dimerization and root growth were partially restored in 2F-Fuc-treated seedlings by addition of boric acid, suggesting that the growth phenotype caused by 2F-Fuc was due to a deficiency of RG-II dimerization. Closer investigation of the 2F-Fuc-induced growth phenotype demonstrated that cell division is not affected by 2F-Fuc treatments. In contrast, the inhibitor suppressed elongation of root cells and promoted the emergence of adventitious roots. This study further emphasizes the importance of RG-II in cell elongation and the utility of glycosyltransferase inhibitors as new tools for studying the functions of cell wall polysaccharides in plant development. Moreover, supplementation experiments with borate suggest that the function of boron in plants might not be restricted to RG-II cross-linking, but that it might also be a signal molecule in the cell wall integrity-sensing mechanism.

  11. 杂种落叶松连续繁殖与插穗生根关系的生理研究%Physiological Research on the Relationship between Repeated Cutting and Rooting of Larix

    Institute of Scientific and Technical Information of China (English)

    孙晓梅; 韩华; 王笑山; 谢允慧

    2012-01-01

    The process of adventitious root development of original and partial ortet cuttings of Larix was investigated in the experiment. The effect of repeated cutting on cuttings ' rooting was studied, and the changes of endogenous hormones content in different stages of adventitious root development were analyzed. The results showed that 13-31 days after cottage were the period key to rooting, the formation rate of callus and the growth speed of young roots of partial ortet cuttings were higher than that of the original ones. The effect of repeated cutting on cuttings' rooting was remarkable, especially the low-rooting percentage ortets, the rooting traits were remarkably improved. The repeated cutting impacted on the self-owned hormone contents, especially IAA, which was obviously higher than that in original ortet cuttings. The hormone ratio of( IAA + GA3 + ZR)/ABA of partial ortet cuttings was higher than the original ones during adventitious root development, and the trend was similar to the change trend of rooting ability, which could be used as an index of rooting ability between original and partial ortet cuttings.%观察了日×长杂种落叶松连续繁殖插穗不定根发育进程,研究了连续繁殖对插穗生根力衰退的阻滞效应,并分析了一轮采穗圃与原株采穗圃插穗不定根发育期内源激素含量的动态变化.结果表明:扦插后13~31 d是愈伤组织形成和不定根原始体分化发育的关键期,此时一轮分生株愈伤组织形成和不定根发育均优于原株.连续繁殖对插穗生根性状有显著作用,尤其是生根率很低的原株,经过一轮繁殖后,生根性状有极显著提高.连续繁殖影响插穗自身激素含量,尤其是IAA,经过一轮繁殖后,含量明显高于原株.从不定根发育过程中激素的动态变化看,一轮分生株插穗(IAA+GA3+ZR)/ABA比值在不定根发育前期明显高于原株,与生根率的变化一致,可用来衡量不同繁殖次数插穗生根性状的优劣.

  12. Do roots mind the gap?

    OpenAIRE

    A. Carminati; Vetterlein, D; Koebernick, N.; Blaser, S; Weller, U; Vogel, H.-J.

    2012-01-01

    Roots need to be in good contact with the soil to take up water and nutrients. However, when the soil dries and roots shrink, air-filled gaps form at the root-soil interface. Do gaps actually limit the root water uptake, or do they form after water flow in soil is already limiting?Four white lupins were grown in cylinders of 20 cm height and 8 cm diameter. The dynamics of root and soil structure were recorded using X-ray CT at regular intervals during one drying/wetting cycle. Tensiometers we...

  13. Root aeration improves growth and nitrogen accumulation in rice seedlings under low nitrogen.

    Science.gov (United States)

    Zhu, Jingwen; Liang, Jing; Xu, Zhihui; Fan, Xiaorong; Zhou, Quansuo; Shen, Qirong; Xu, Guohua

    2015-11-16

    In wetland soils, changes in oxygen (O2) level in the rhizosphere are believed to influence the behaviour of nutrients and their usage by plants. However, the effect of aeration on nitrogen (N) acquisition under different N supply conditions remains largely unknown. In this study, the rice cultivars Yangdao 6 (YD6, with higher root aerenchyma abundance) and Nongken 57 (NK57, with lower root aerenchyma abundance) were used to evaluate the effects of aeration on rice growth and N accumulation. Our results showed that the number of adventitious roots and the root surface area increased significantly, and ethylene production and aerenchyma formation decreased in both cultivars after external aeration (EA). Five N treatments, including no N (-N), 0.125 mM NH4NO3 (LN), 1.25 mM Ca(NO3)2 (NO3-N), 1.25 mM (NH4)2SO4 (NH4-N) and 1.25 mM NH4NO3 (N/N), were applied to YD6 and NK57 for 2 days under internal aeration or EA conditions. External aeration increased the root biomass in both cultivars and the shoot biomass in NK57 by 18-50 %. The total N concentrations in roots of YD6 grown under -N and LN and of NK57 grown under NO3-N were increased by EA. Expression of OsPAD4, one of four putative genes regulating aerenchyma formation, showed a similar pattern alongside changes in the ethylene level in the EA-treated rice irrespective of the N treatments. Furthermore, expression of the high-affinity nitrate transporter gene OsNRT2.1 was increased by EA under -N, LN and NO3-N conditions. Our data provide evidence of an interaction between O2 and the supply of N in ethylene production, aerenchyma formation and N nutrition through modification of the expression of OsPAD4 and OsNRT2.1.

  14. The Roots of Beowulf

    Science.gov (United States)

    Fischer, James R.

    2014-01-01

    The first Beowulf Linux commodity cluster was constructed at NASA's Goddard Space Flight Center in 1994 and its origins are a part of the folklore of high-end computing. In fact, the conditions within Goddard that brought the idea into being were shaped by rich historical roots, strategic pressures brought on by the ramp up of the Federal High-Performance Computing and Communications Program, growth of the open software movement, microprocessor performance trends, and the vision of key technologists. This multifaceted story is told here for the first time from the point of view of NASA project management.

  15. Philosophical Roots of Cosmology

    Science.gov (United States)

    Ivanovic, M.

    2008-10-01

    We shall consider the philosophical roots of cosmology in the earlier Greek philosophy. Our goal is to answer the question: Are earlier Greek theories of pure philosophical-mythological character, as often philosophers cited it, or they have scientific character. On the bases of methodological criteria, we shall contend that the latter is the case. In order to answer the question about contemporary situation of the relation philosophy-cosmology, we shall consider the next question: Is contemporary cosmology completely independent of philosophical conjectures? The answer demands consideration of methodological character about scientific status of contemporary cosmology. We also consider some aspects of the relation contemporary philosophy-cosmology.

  16. ANALGESIC ACTIVITY OF ROOT EXTRACT OF SOLANUM MELONGENA LINN ROOT

    OpenAIRE

    Srivastava Ashish; Sanjay Yadav

    2011-01-01

    The present study was aimed at Pharmacognostic study and biological evaluation of analgesic activity of plants roots. The roots of plants were studies for Pharmacognostic characteristics namely, morphology, microscopy, physicochemical parameters, which can be of utilized in identification/authentication of the plant and/or its roots in crude drug form. The preliminary phytochemical screening of the dry residue was carried out by the chemical test and thin layer chromatographic method. The p...

  17. Geophysical Imaging of Root Architecture and Root-soil Interaction

    Science.gov (United States)

    Wu, Y.; Dafflon, B.; Hubbard, S. S.

    2015-12-01

    Roots play a critical role in controlling water and nutrient uptake, soil biogeochemical processes, as well as the physical anchorage for plants. While important processes, such as root hydraulic redistribution for optimal growth and survival have been recognized, representation of roots in climate models, e.g. its carbon storage, carbon resilience, root biomass, and role in regulating water and carbon fluxes across the rhizosphere and atmosphere interface is still challenging. Such a challenge is exacerbated because of the large variations of root architecture and function across species and locations due to both genetic and environmental controls and the lack of methods for quantifying root mass, distribution, dynamics and interaction with soils at field scales. The scale, complexity and the dynamic nature of plant roots call for minimally invasive methods capable of providing quantitative estimation of root architecture, dynamics over time and interactions with the soils. We present a study on root architecture and root-soil interactions using geophysical methods. Parameters and processes of interests include (1) moisture dynamics around root zone and its interaction with plant transpiration and environmental controls and (2) estimation of root structure and properties based on geophysical signals. Both pot and field scale studies were conducted. The pot scale experiments were conducted under controlled conditions and were monitored with cross-well electrical resistivity tomography (ERT), TDR moisture sensors and temperature probes. Pots with and without a tree were compared and the moisture conditions were controlled via a self regulated pumping system. Geophysical monitoring revealed interactions between roots and soils under dynamic soil moisture conditions and the role of roots in regulating the response of the soil system to changes of environmental conditions, e.g. drought and precipitation events. Field scale studies were conducted on natural trees using

  18. Perennial roots to immortality.

    Science.gov (United States)

    Munné-Bosch, Sergi

    2014-10-01

    Maximum lifespan greatly varies among species, and it is not strictly determined; it can change with species evolution. Clonal growth is a major factor governing maximum lifespan. In the plant kingdom, the maximum lifespans described for clonal and nonclonal plants vary by an order of magnitude, with 43,600 and 5,062 years for Lomatia tasmanica and Pinus longaeva, respectively. Nonclonal perennial plants (those plants exclusively using sexual reproduction) also present a huge diversity in maximum lifespans (from a few to thousands of years) and even more interestingly, contrasting differences in aging patterns. Some plants show a clear physiological deterioration with aging, whereas others do not. Indeed, some plants can even improve their physiological performance as they age (a phenomenon called negative senescence). This diversity in aging patterns responds to species-specific life history traits and mechanisms evolved by each species to adapt to its habitat. Particularities of roots in perennial plants, such as meristem indeterminacy, modular growth, stress resistance, and patterns of senescence, are crucial in establishing perenniality and understanding adaptation of perennial plants to their habitats. Here, the key role of roots for perennial plant longevity will be discussed, taking into account current knowledge and highlighting additional aspects that still require investigation. PMID:24563283

  19. ROOT Tutorial for Summer Students

    CERN Document Server

    CERN. Geneva; Piparo, Danilo

    2015-01-01

    ROOT is a "batteries-included" tool kit for data analysis, storage and visualization. It is widely used in High Energy Physics and other disciplines such as Biology, Finance and Astrophysics. This event is an introductory tutorial to ROOT and comprises a front lecture and hands on exercises. IMPORTANT NOTE: The tutorial is based on ROOT 6.04 and NOT on the ROOT5 series.  IMPORTANT NOTE: if you have ROOT 6.04 installed on your laptop, you will not need to install any virtual machine. The instructions showing how to install the virtual machine on which you can find ROOT 6.04 can be found under "Material" on this page.

  20. Removal of root filling materials.

    LENUS (Irish Health Repository)

    Duncan, H.F. Chong, B.S.

    2011-05-01

    Safe, successful and effective removal of root filling materials is an integral component of non-surgical root canal re-treatment. Access to the root canal system must be achieved in order to negotiate to the canal terminus so that deficiencies in the original treatment can be rectified. Since a range of materials have been advocated for filling root canals, different techniques are required for their removal. The management of commonly encountered root filling materials during non-surgical re-treatment, including the clinical procedures necessary for removal and the associated risks, are reviewed. As gutta-percha is the most widely used and accepted root filling material, there is a greater emphasis on its removal in this review.

  1. Comparing Leaf and Root Insertion

    Directory of Open Access Journals (Sweden)

    Jaco Geldenhuys

    2010-07-01

    Full Text Available We consider two ways of inserting a key into a binary search tree: leaf insertion which is the standard method, and root insertion which involves additional rotations. Although the respective cost of constructing leaf and root insertion binary search trees trees, in terms of comparisons, are the same in the average case, we show that in the worst case the construction of a root insertion binary search tree needs approximately 50% of the number of comparisons required by leaf insertion.

  2. The PIN1 family gene PvPIN1 is involved in auxin-dependent root emergence and tillering in switchgrass.

    Science.gov (United States)

    Xu, Kaijie; Sun, Fengli; Wang, Yongfeng; Shi, Lili; Liu, Shudong; Xi, Yajun

    2016-03-01

    Switchgrass (Panicum virgatum L.; family Poaceae) is a warm-season C4 perennial grass. Tillering plays an important role in determining the morphology of aboveground parts and the final biomass yield of switchgrass. Auxin distribution in plants can affect a variety of important growth and developmental processes, including the regulation of shoot and root branching, plant resistance and biological yield. Auxin transport and gradients in plants are mediated by influx and efflux carriers. PvPIN1, a switchgrass PIN1-like gene that is involved in regulating polar transport, is a putative auxin efflux carrier. Neighbor-joining analysis using sequences deposited in NCBI databases showed that the PvPIN1gene belongs to the PIN1 family and is evolutionarily closer to the Oryza sativa japonica group. Tiller emergence and development was significantly promoted in plants subjected toPvPIN1 RNA interference (RNAi), which yielded a phenotype similar to that of wild-type plants treated with the auxin transport inhibitor TIBA (2,3,5-triiodobenzoic acid). A transgenic approach that inducedPvPIN1 gene overexpression or suppression altered tiller number and the shoot/root ratio. These data suggest that PvPIN1plays an important role in auxin-dependent adventitious root emergence and tillering. PMID:27007900

  3. The PIN1 family gene PvPIN1 is involved in auxin-dependent root emergence and tillering in switchgrass

    Directory of Open Access Journals (Sweden)

    Kaijie Xu

    2016-03-01

    Full Text Available Abstract Switchgrass (Panicum virgatum L.; family Poaceae is a warm-season C4 perennial grass. Tillering plays an important role in determining the morphology of aboveground parts and the final biomass yield of switchgrass. Auxin distribution in plants can affect a variety of important growth and developmental processes, including the regulation of shoot and root branching, plant resistance and biological yield. Auxin transport and gradients in plants are mediated by influx and efflux carriers. PvPIN1, a switchgrass PIN1-like gene that is involved in regulating polar transport, is a putative auxin efflux carrier. Neighbor-joining analysis using sequences deposited in NCBI databases showed that the PvPIN1gene belongs to the PIN1 family and is evolutionarily closer to the Oryza sativa japonica group. Tiller emergence and development was significantly promoted in plants subjected toPvPIN1 RNA interference (RNAi, which yielded a phenotype similar to that of wild-type plants treated with the auxin transport inhibitor TIBA (2,3,5-triiodobenzoic acid. A transgenic approach that inducedPvPIN1 gene overexpression or suppression altered tiller number and the shoot/root ratio. These data suggest that PvPIN1plays an important role in auxin-dependent adventitious root emergence and tillering.

  4. Feynman Diagrams and Rooted Maps

    CERN Document Server

    Prunotto, A; Czerski, P

    2013-01-01

    The {\\em Rooted Maps Theory}, a branch of the Theory of Homology, is shown to be a powerful tool for investigating the topological properties of Feynman diagrams, related to the single particle propagator in the quantum many-body systems. The numerical correspondence between the number of this class of Feynman diagrams as a function of perturbative order and the number of rooted maps as a function of the number of edges is studied. A graphical procedure to associate Feynman diagrams and rooted maps is then stated. Finally, starting from rooted maps principles, an original definition of the {\\em genus of a Feynman diagram}, which totally differs from the usual one, is given.

  5. On roots of Dehn twists

    CERN Document Server

    Monden, Naoyuki

    2009-01-01

    Margalit and Schleimer constructed nontrivial roots of the Dehn twist about a nonseparating curve. We prove that the conjugacy classes of roots of the Dehn twist about a nonseparating curve correspond to the conjugacy classes of periodic maps with certain conditions. Futhermore, we give data set which determine the conjugacy class of a root. As a consequence, we can find the minimum degree and the maximum degree, and show that the degree must be odd. Also, we give Dehn twist expression of the root of degree 3.

  6. Maximal rank root subsystems of hyperbolic root systems

    OpenAIRE

    Tumarkin, P.

    2003-01-01

    A Kac-Moody algebra is called hyperbolic if it corresponds to a generalized Cartan matrix of hyperbolic type. We study root subsystems of root systems of hyperbolic algebras. In this paper, we classify maximal rank regular hyperbolic subalgebras of hyperbolic Kac-Moody algebras.

  7. Perturbation of cytokinin and ethylene-signalling pathways explain the strong rooting phenotype exhibited by Arabidopsis expressing the Schizosaccharomyces pombe mitotic inducer, cdc25

    Directory of Open Access Journals (Sweden)

    Spadafora Natasha D

    2012-03-01

    Full Text Available Abstract Background Entry into mitosis is regulated by cyclin dependent kinases that in turn are phosphoregulated. In most eukaryotes, phosphoregulation is through WEE1 kinase and CDC25 phosphatase. In higher plants a homologous CDC25 gene is unconfirmed and hence the mitotic inducer Schizosaccharomyces pombe (Sp cdc25 has been used as a tool in transgenic plants to probe cell cycle function. Expression of Spcdc25 in tobacco BY-2 cells accelerates entry into mitosis and depletes cytokinins; in whole plants it stimulates lateral root production. Here we show, for the first time, that alterations to cytokinin and ethylene signaling explain the rooting phenotype elicited by Spcdc25 expression in Arabidopsis. Results Expressing Spcdc25 in Arabidopsis results in increased formation of lateral and adventitious roots, a reduction of primary root width and more isodiametric cells in the root apical meristem (RAM compared with wild type. Furthermore it stimulates root morphogenesis from hypocotyls when cultured on two way grids of increasing auxin and cytokinin concentrations. Microarray analysis of seedling roots expressing Spcdc25 reveals that expression of 167 genes is changed by > 2-fold. As well as genes related to stress responses and defence, these include 19 genes related to transcriptional regulation and signaling. Amongst these was the up-regulation of genes associated with ethylene synthesis and signaling. Seedlings expressing Spcdc25 produced 2-fold more ethylene than WT and exhibited a significant reduction in hypocotyl length both in darkness or when exposed to 10 ppm ethylene. Furthermore in Spcdc25 expressing plants, the cytokinin receptor AHK3 was down-regulated, and endogenous levels of iPA were reduced whereas endogeous IAA concentrations in the roots increased. Conclusions We suggest that the reduction in root width and change to a more isodiametric cell phenotype in the RAM in Spcdc25 expressing plants is a response to ethylene over

  8. Radiographing roots and shoots

    International Nuclear Information System (INIS)

    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.)

  9. 不同花生品种幼叶丛生芽诱导研究%Efficient Induction of Adventitious Buds from Peanut Leaflets of Various Varieties

    Institute of Scientific and Technical Information of China (English)

    苗利娟; 张新友; 黄冰艳; 董文召; 汤丰收; 秦利; 高伟; 韩锁义

    2012-01-01

    In order to screen peanut genotypes with high induction efficiency of adventitious buds and to set up a high efficient regeneration system of peanut leaflets,MS and 1/2MS medium for peanut germination were compared based on the culture response of 22 different genotypes. The differences in induction frequency among various genotypes and the effects of Carb and Cef on the adventitious buds induction were also investigated using leaflets from 4 day-germinated peanut seeds as explants. It was shown that the germination rates of peanut seeds on 1/2MS medium were higher than those on MS medium. There were significant differences in bud induction rates among 22 genotypes. Moreover,the genotypes with induction rates above 90% were Hz006,Hz001 ,Hz012 and Hz037,while Hz015 had the lowest induction rate of 31. 8%. No inhibition to bud induction was detected with 500 mg/L of Carb added to the medium and the induction rate of Hz009 was increased by 13. 5 percentage points compared with that of CK. For most of the genotypes Cef had a negative effect on bud induction and the bud induction rate of Hz010 on the medium with Cef added was significantly dropped by 48. 5 percentage points. It was concluded that 1/2MS was the suitable medium for peanut seeds germination and the genotypes of Hz006, Hz001, Hz012 and Hz037 with high induction rate were recommended for peanut genetic transformation. Additionally, Carb was a better antibiotic than Cef when they were used to control the over growth of agrobacteria on leaflet explants during the agrobacteria mediated transformation.%为筛选高诱导率的花生品种并建立花生的高频再生体系,比较了22个花生品种在MS和1/2MS培养基中的萌发情况,同时以4d苗龄的花生幼叶为外植体,研究了花生幼叶丛生芽诱导率的品种差异性,以及羧苄青霉素(Carb)和头孢霉素(Cef)对花生丛生芽诱导的影响.结果表明:22个花生品种的种子在1/2MS培养基上萌发率均比在MS培养基上

  10. Compensatory Root Water Uptake of Overlapping Root Systems

    Science.gov (United States)

    Agee, E.; Ivanov, V. Y.; He, L.; Bisht, G.; Shahbaz, P.; Fatichi, S.; Gough, C. M.; Couvreur, V.; Matheny, A. M.; Bohrer, G.

    2015-12-01

    Land-surface models use simplified representations of root water uptake based on biomass distributions and empirical functions that constrain water uptake during unfavorable soil moisture conditions. These models fail to capture the observed hydraulic plasticity that allows plants to regulate root hydraulic conductivity and zones of active uptake based on local gradients. Recent developments in root water uptake modeling have sought to increase its mechanistic representation by bridging the gap between physically based microscopic models and computationally feasible macroscopic approaches. It remains to be demonstrated whether bulk parameterization of microscale characteristics (e.g., root system morphology and root conductivity) can improve process representation at the ecosystem scale. We employ the Couvreur method of microscopic uptake to yield macroscopic representation in a coupled soil-root model. Using a modified version of the PFLOTRAN model, which represents the 3-D physics of variably saturated soil, we model a one-hectare temperate forest stand under natural and synthetic climatic forcing. Our results show that as shallow soil layers dry, uptake at the tree and stand level shift to deeper soil layers, allowing the transpiration stream demanded by the atmosphere. We assess the potential capacity of the model to capture compensatory root water uptake. Further, the hydraulic plasticity of the root system is demonstrated by the quick response of uptake to rainfall pulses. These initial results indicate a promising direction for land surface models in which significant three-dimensional information from large root systems can be feasibly integrated into the forest scale simulations of root water uptake.

  11. Properties of Estimated Characteristic Roots

    DEFF Research Database (Denmark)

    Nielsen, Bent; Nielsen, Heino Bohn

    Estimated characteristic roots in stationary autoregressions are shown to give rather noisy information about their population equivalents. This is remarkable given the central role of the characteristic roots in the theory of autoregressive processes. In the asymptotic analysis the problems appear...

  12. Project Work on Plant Roots.

    Science.gov (United States)

    Devonald, V. G.

    1986-01-01

    Methods of investigating plant root growth developed for research purposes can be adopted for student use. Investigations of the effect of water table level and of ethylene concentration are described, and techniques of measuring root growth are explained. (Author/ML)

  13. Structural and physiological changes of Chromolaena odorata during formation of adventitious root%飞机草不定根形成过程中的结构和生理变化

    Institute of Scientific and Technical Information of China (English)

    何海旺; 罗海玲; 龚明霞; 何龙飞

    2015-01-01

    [目的]研究飞机草不定根形成过程中的解剖结构和生理变化,了解其不定根形成特性,为进一步阐明飞机草无性繁殖机制奠定基础.[方法]通过扦插试验,研究飞机草在不同基质、不同含水量中的生根情况,并在生根过程中进行解剖结构观察,同时测定相关内源激素含量、POD活性及黄酮含量.[结果]飞机草在菜同土、红土、河沙3种基质中生根率均为100.0%.极度干旱(水分含量0)或水分过多时(80%)不能生根,在基质含水量为20%~60%时均能迅速长出不定根.解剖结构发现,飞机草茎段皮层中没有环状厚壁细胞,皮层薄且髓部较大,不定根原基产生于束中形成层,生根过程中没有愈伤组织产生,根原基形成和不定根突破表皮的时间分别为扦插后3和7d.在飞机草不定根形成过程中,相关生理指标均发生显著变化;IAA含量总体呈上升—下降—上升的变化趋势,ABA及黄酮作为生根抑制物,其含量在生根过程中总体呈下降趋势;ZT含量峰值出现在扦插后3 d;POD活性最低值出现在扦插后1d,最高值出现在扦插后3d,且生根过程中的活性比未扦插时极显著升高.[结论]飞机草不定根形成具有极强的环境适应性,其解剖结构和扦插过程中内源激素含量的变化均符合易生根植物特征.

  14. Anatomical Structure of Stem and Adventitious Root Formation of Feijoa Cuttings%费约果茎解剖结构与插条不定根的形成

    Institute of Scientific and Technical Information of China (English)

    张猛; 王丹; 汤浩茹; 任少雄; 刘仁道

    2010-01-01

    @@ 费约果(Feijoa sellowiana)是桃金娘科多年生亚热带常绿灌木,原产于巴西东南部和乌拉圭,因其果实香味类似凤梨(Ananas comosus),又名凤梨番石榴(Thorp et al.,2002).费约果在新西兰、美国、法国、西班牙、俄罗斯、澳大利亚、日本等国有栽培,我国江苏、上海、四川、浙江等南方地区也有一定规模的种植.费约果作为一种集观赏、食用与药用为一体的新兴果树,在食品、药品、化妆品等领域具有广阔的应用前景(Nakashima,2001;Hardy et al.,1970;Kolesnik et al.,1991).在四川省外国专家局引智项目资助下,2004年,西南科技大学王丹教授从新西兰引进少量费约果苗木后,对其在四川地区的适应性以及综合性状进行了初步研究,认为费约果能够适应四川地区气候,并能保持其优良的食用与观赏特性,是一种极具发展潜力的食用兼观赏的树种(王丹等,2007).

  15. Cassava root membrane proteome reveals activities during storage root maturation.

    Science.gov (United States)

    Naconsie, Maliwan; Lertpanyasampatha, Manassawe; Viboonjun, Unchera; Netrphan, Supatcharee; Kuwano, Masayoshi; Ogasawara, Naotake; Narangajavana, Jarunya

    2016-01-01

    Cassava (Manihot esculenta Crantz) is one of the most important crops of Thailand. Its storage roots are used as food, feed, starch production, and be the important source for biofuel and biodegradable plastic production. Despite the importance of cassava storage roots, little is known about the mechanisms involved in their formation. This present study has focused on comparison of the expression profiles of cassava root proteome at various developmental stages using two-dimensional gel electrophoresis and LC-MS/MS. Based on an anatomical study using Toluidine Blue, the secondary growth was confirmed to be essential during the development of cassava storage root. To investigate biochemical processes occurring during storage root maturation, soluble and membrane proteins were isolated from storage roots harvested from 3-, 6-, 9-, and 12-month-old cassava plants. The proteins with differential expression pattern were analysed and identified to be associated with 8 functional groups: protein folding and degradation, energy, metabolism, secondary metabolism, stress response, transport facilitation, cytoskeleton, and unclassified function. The expression profiling of membrane proteins revealed the proteins involved in protein folding and degradation, energy, and cell structure were highly expressed during early stages of development. Integration of these data along with the information available in genome and transcriptome databases is critical to expand knowledge obtained solely from the field of proteomics. Possible role of identified proteins were discussed in relation with the activities during storage root maturation in cassava.

  16. Effects of Different Kinds of Exogenous Auxin on the Growth of Rice Roots under Cadmium Stress%不同外源生长素对镉胁迫水稻根系生长的影响

    Institute of Scientific and Technical Information of China (English)

    韩明明; 胡凡; 王凯; 赵凤云

    2010-01-01

    以水稻中花11号为材料,测定了不同外源生长素对镉胁迫水稻根系生长发育的影响.结果表明,0.1 mmol/L镉诱导水稻初生根、不定根和侧根的伸长生长且侧根的数目也增加,但抑制地上部分的生长.在镉胁迫下添加不同浓度的生长素如NAA、IAA、IBA和2,4-D都明显改变根系的生长且变化趋势相似.即浓度为10-9~10-7M时,促进镉胁迫水稻初生根和不定根的伸长生长,其中以浓度为10-8M时,促进作用最强;当浓度高于10-7M时,反而抑制了根的生长;添加4种外源生长素均不能解除镉对地上部分的抑制作用,不过镉胁迫下添加10-9~10-8M的NAA能在一定程度上改善镉胁迫水稻的生长.在相同浓度条件下,不同生长素对初生根和不定根上侧根的形成和发育既有相似之处,也存在一定差异.%[Objective]The aim was to study the effect of different kinds of exogenous auxin on the growth of rice roots under cadmium stress.[Method]Oryza sativa L.cv Z.honghua No.11 was used as experimental materials to detect the effect of different kinds of exogenous auxin on the growth of rice roots.[Result]The results showed that 0.1 mmol/L Cd treatment could not only increase primary,adventitious and lateral root length but also lateral root number,whereas the shoot growth was inhibited.When supplemented with different concentrations of NAA,IAA,IBA and 2,4-D,the growth of root system varied and similar change trend had been found.At the auxin concentration of 10-9-10-7 moVL in particular 10-8 mol/L,all four kinds of auxin promoted the elongation growth of primary and adventitious roots,but inhibition was observed when auxin was higher than 10-7 mol/L.The decreased shoot growth caused by Cd could not be counteracted by supplementing with the four kinds of auxin.However,at the auxin concentration of 10-9-10-8 mol/L,NAA could improve rice growth under Cd stress condition.The formation and development of lateral roots on primary and

  17. [Normal and Adventitious Breath Sounds].

    Science.gov (United States)

    Koehler, U; Hildebrandt, O; Kerzel, S; Urban, C; Hoehle, L; Weissflog, A; Nikolaizik, W; Koehler, J; Sohrabi, K; Gross, V

    2016-06-01

    Auscultation of the lung is an inexpensive, noninvasive and easy-to-perform tool. It is an important part of the physical examination and is help ful to distinguish physiological respiratory sounds from pathophysiological events. Computerized lung sound analysis is a powerful tool for optimizing and quantifying electronic auscultation based on the specific lung sound spectral characteristics. The automatic analysis of respiratory sounds assumes that physiological and pathological sounds are reliably analyzed based on special algorithms. The development of automated long-term lungsound monitors enables objective assessment of different respiratory symptoms.

  18. Medico-legal aspects of vertical root fractures in root filled teeth

    DEFF Research Database (Denmark)

    Rosen, E; Tsesis, I; Tamse, A;

    2012-01-01

    To analyse the medico-legal aspects of vertical root fracture (VRF) following root canal treatment (RCT).......To analyse the medico-legal aspects of vertical root fracture (VRF) following root canal treatment (RCT)....

  19. Sublethal concentrations of salicylic acid decrease the formation of reactive oxygen species but maintain an increased nitric oxide production in the root apex of the ethylene-insensitive never ripe tomato mutants.

    Science.gov (United States)

    Tari, Irma; Poór, Péter; Gémes, Katalin

    2011-09-01

    The pattern of salicylic acid (SA)-induced production of reactive oxygen species (ROS) and nitric oxide (NO) were different in the apex of adventitious roots in wild-type and in the ethylene-insensitive never ripe (Nr) mutants of tomato (Solanum lycopersicum L. cv Ailsa Craig). ROS were upregulated, while NO remained at the control level in apical root tissues of wildtype plants exposed to sublethal concentrations of SA. In contrast, Nr plants expressing a defective ethylene receptor displayed a reduced level of RO S and a higher NO content in the apical root cells. In wild-type plants NO production seems to be RO S(H2O2)-dependent at cell death-inducing concentrations of SA, indicating that ROS and NO may interact to trigger oxidative cell death. In the absence of significant RO S accumulation, the increased NO production caused moderate reduction in cell viability in root apex of Nr plants exposed to 10(-3) M SA. This suggests that a functional ethylene signaling pathway is necessary for the control of ROS and NO production induced by SA.

  20. Gravisensing in roots

    Science.gov (United States)

    Perbal, G.

    1999-01-01

    The mode of gravisensing in higher plants is not yet elucidated. Although, it is generally accepted that the amyloplasts (statoliths) in the root cap cells (statocytes) are responsible for susception of gravity. However, the hypothesis that the whole protoplast acts as gravisusceptor cannot be dismissed. The nature of the sensor that is able to transduce and amplify the mechanical energy into a biochemical factor is even more controversial. Several cell structures could potentially serve as gravireceptors: the endoplasmic reticulum, the actin network, the plasma membrane, or the cytoskeleton associated with this membrane. The nature of the gravisusceptors and gravisensors is discussed by taking into account the characteristics of the gravitropic reaction with respect to the presentation time, the threshold acceleration, the reciprocity rule, the deviation from the sine rule, the movement of the amyloplasts, the pre-inversion effect, the response of starch free and intermediate mutants and the effects of cytochalasin treatment. From this analysis, it can be concluded that both the amyloplasts and the protoplast could be the gravisusceptors, the former being more efficient than the latter since they can focus pressure on limited areas. The receptor should be located in the plasma membrane and could be a stretch-activated ion channel.

  1. Root anatomical phenes predict root penetration ability and biomechanical properties in maize (Zea Mays)

    OpenAIRE

    Chimungu, Joseph G.; Loades, Kenneth W.; Lynch, Jonathan P.

    2015-01-01

    The ability of roots to penetrate hard soil is important for crop productivity but specific root phenes contributing to this ability are poorly understood. Root penetrability and biomechanical properties are likely to vary in the root system dependent on anatomical structure. No information is available to date on the influence of root anatomical phenes on root penetrability and biomechanics. Root penetration ability was evaluated using a wax layer system. Root tensile and bending strength we...

  2. 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

  3. Effect of parameter choice in root water uptake models – the arrangement of root hydraulic properties within the root architecture affects dynamics and efficiency of root water uptake

    OpenAIRE

    Bechmann, M.; Schneider, C; Carminati, A.; Vetterlein, D.; Attinger, S.; Hildebrandt, A

    2014-01-01

    Detailed three-dimensional models of root water uptake have become increasingly popular for investigating the process of root water uptake. However, they suffer from a lack of information on important parameters, particularly on the spatial distribution of root axial and radial conductivities, which vary greatly along a root system. In this paper we explore how the arrangement of those root hydraulic properties and branching within the root system affects modelled uptake dynamics, xylem water...

  4. Root pruning reduces root competition in living mulch cropping systems

    OpenAIRE

    Båth, B.; Kristensen, Hanne Lakkenborg; Thorup-Kristensen, Kristian

    2009-01-01

    In intercropping systems with a cash crop and a living mulch intercrop, competition between the cash crop and the intercrop (the living mulch) often reduces the yield of the cash crop. This project investigated (1) the influence of root pruning of living mulches on aboveground biomass of white cabbage. Below-ground growth and competition were examined by measuring (2) root distribution in minirhizotrons and (3) uptake of 15N placed at different soil depths. Two field experiments were carried ...

  5. Towards a multidimensional root trait framework: a tree root review.

    Science.gov (United States)

    Weemstra, Monique; Mommer, Liesje; Visser, Eric J W; van Ruijven, Jasper; Kuyper, Thomas W; Mohren, Godefridus M J; Sterck, Frank J

    2016-09-01

    Contents 1159 I. 1159 II. 1161 III. 1164 IV. 1166 1167 References 1167 SUMMARY: The search for a root economics spectrum (RES) has been sparked by recent interest in trait-based plant ecology. By analogy with the one-dimensional leaf economics spectrum (LES), fine-root traits are hypothesised to match leaf traits which are coordinated along one axis from resource acquisitive to conservative traits. However, our literature review and meta-level analysis reveal no consistent evidence of an RES mirroring an LES. Instead the RES appears to be multidimensional. We discuss three fundamental differences contributing to the discrepancy between these spectra. First, root traits are simultaneously constrained by various environmental drivers not necessarily related to resource uptake. Second, above- and belowground traits cannot be considered analogues, because they function differently and might not be related to resource uptake in a similar manner. Third, mycorrhizal interactions may offset selection for an RES. Understanding and explaining the belowground mechanisms and trade-offs that drive variation in root traits, resource acquisition and plant performance across species, thus requires a fundamentally different approach than applied aboveground. We therefore call for studies that can functionally incorporate the root traits involved in resource uptake, the complex soil environment and the various soil resource uptake mechanisms - particularly the mycorrhizal pathway - in a multidimensional root trait framework. PMID:27174359

  6. Ultrasonic cleaning of root canals

    Science.gov (United States)

    Verhaagen, Bram; Boutsioukis, Christos; Jiang, Lei-Meng; Macedo, Ricardo; van der Sluis, Luc; Versluis, Michel

    2011-11-01

    A crucial step during a dental root canal treatment is irrigation, where an antimicrobial fluid is injected into the root canal system to eradicate all bacteria. Agitation of the fluid using an ultrasonically vibrating miniature file has shown significant improvement in cleaning efficacy over conventional syringe irrigation. However, the physical mechanisms underlying the cleaning process, being acoustic streaming, cavitation or chemical activity, and combinations thereof, are not fully understood. High-speed imaging allows us to visualize the flow pattern and cavitation in a root canal model at microscopic scales, at timescales relevant to the cleaning processes (microseconds). MicroPIV measurements of the induced acoustic streaming are coupled to the oscillation characteristics of the file as simulated numerically and measured with a laser vibrometer. The results give new insight into the role of acoustic streaming and the importance of the confinement for the cleaning of root canals.

  7. Root coverage with bridge flap

    Directory of Open Access Journals (Sweden)

    Pushpendra Kumar Verma

    2013-01-01

    Full Text Available Gingival recession in anterior teeth is a common concern due to esthetic reasons or root sensitivity. Gingival recession, especially in multiple anterior teeth, is of huge concern due to esthetic reasons. Various mucogingival surgeries are available for root coverage. This case report presents a new bridge flap technique, which allows the dentist not only to cover the previously denuded root surfaces but also to increase the zone of attached gingiva at a single step. In this case, a coronally advanced flap along with vestibular deepening technique was used as root coverage procedure for the treatment of multiple recession-type defect. Here, vestibular deepening technique is used to increase the width of the attached gingiva. The predictability of this procedure results in an esthetically healthy periodontium, along with gain in keratinized tissue and good patient′s acceptance.

  8. Root Patterns in Heterogeneous Soils

    Science.gov (United States)

    Dara, A.; Moradi, A. B.; Carminati, A.; Oswald, S. E.

    2010-12-01

    Heterogeneous water availability is a typical characteristic of soils in which plant roots grow. Despite the intrinsic heterogeneity of soil-plant water relations, we know little about the ways how plants respond to local environmental quality. Furthermore, increasing use of soil amendments as partial water reservoirs in agriculture calls for a better understanding of plant response to soil heterogeneity. Neutron radiography is a non-invasive imaging that is highly sensitive to water and root distribution and that has high capability for monitoring spatial and temporal soil-plant water relations in heterogeneous systems. Maize plants were grown in 25 x 30 x 1 cm aluminum slabs filled with sandy soil. On the right side of the compartments a commercial water absorbent (Geohumus) was mixed with the soil. Geohumus was distributed with two patterns: mixed homogeneously with the soil, and arranged as 1-cm diameter aggregates (Fig. 1). Two irrigation treatments were applied: sufficient water irrigation and moderate water stress. Neutron radiography started 10 days after planting and has been performed twice a day for one week. At the end of the experiment, the containers were opened, the root were removed and dry root weight in different soil segments were measured. Neutron radiography showed root growth tendency towards Geohumus treated parts and preferential water uptake from Geohumus aggregates. Number and length of fine lateral roots were lower in treated areas compared to the non-treated zone and to control soil. Although corn plants showed an overall high proliferation towards the soil water sources, they decreased production of branches and fine root when water was more available near the main root parts. However there was 50% higher C allocation in roots grown in Geohumus compartments, as derived by the relative dry weight of root. The preferential C allocation in treated regions was higher when plants grew under water stress. We conclude that in addition to the

  9. Roots of unity in orders

    OpenAIRE

    Lenstra Jr., H. W.; Silverberg, A.

    2015-01-01

    We give deterministic polynomial-time algorithms that, given an order, compute the primitive idempotents and determine a set of generators for the group of roots of unity in the order. Also, we show that the discrete logarithm problem in the group of roots of unity can be solved in polynomial time. As an auxiliary result, we solve the discrete logarithm problem for certain unit groups in finite rings. Our techniques, which are taken from commutative algebra, may have further potential in the ...

  10. Eficiência das auxinas (AIB e ANA no enraizamento de miniestacas de clones de Eucalyptus cloeziana F. Muell Auxin (IBA and NAA effects on minicuttings rooting of Eucalyptus cloeziana F. Muell. clones

    Directory of Open Access Journals (Sweden)

    Fernanda Daniele de Almeida

    2007-01-01

    Full Text Available Este trabalho teve como objetivo avaliar a eficiência das auxinas AIB (ácido indolbutírico e ANA (ácido naftalenoacético no enraizamento adventício de miniestacas de clones de Eucalyptus cloeziana. Foram utilizadas miniestacas provenientes de sete clones de Eucalyptus cloeziana, estabelecidos em minijardim clonal, sendo avaliados os efeitos de AIB (0, 1.500, 3.000 e 6.000 mg L-1 na forma líquida e em pó e ANA (0, 3.000 e 6.000 mg L-1 na forma líquida. Os resultados apontaram ser a miniestaquia técnica viável na propagação vegetativa dos clones de Eucalyptus cloeziana estudados, apresentando, de modo geral, alto índice de enraizamento das miniestacas. Os clones com maior potencial de enraizamento adventício responderam mais positivamente às menores dosagens de AIB, enquanto nos clones com capacidade de enraizamento reduzida houve tendência de as maiores dosagens de AIB serem mais eficientes no enraizamento, independentemente da forma de aplicação do fitorregulador (líquido ou pó. O ANA, de modo geral, não influenciou significativamente o enraizamento das miniestacas da maioria dos clones estudados.The present work aimed to evaluate the efficiency of the auxins IBA (indolbutyric acid and NAA (naphtaleneacetic acid on the adventitious rooting of Eucalyptus cloeziana clones. Minicuttings originated from seven Eucalyptus cloeziana clones established in mini-clonal hedge, were evaluated for the effects of IBA (0, 1500, 3000 and 6000 mg L-1 in the liquid and powder forms and NAA (0, 3000 and 6000 mg L-1 in the liquid form. The results showed that minicutting is a viable technique for vegetative propagation of the studied Eucalyptus cloeziana clones, with overall high rooting rates. Clones with higher adventitious rooting potential gave better response to lower IBA doses, while clones with reduced rooting potential were more efficient with higher doses, independently of the form of the applied phytoregulator (powder or liquid. NAA

  11. Plant root-microbe communication in shaping root microbiomes.

    Science.gov (United States)

    Lareen, Andrew; Burton, Frances; Schäfer, Patrick

    2016-04-01

    A growing body of research is highlighting the impacts root-associated microbial communities can have on plant health and development. These impacts can include changes in yield quantity and quality, timing of key developmental stages and tolerance of biotic and abiotic stresses. With such a range of effects it is clear that understanding the factors that contribute to a plant-beneficial root microbiome may prove advantageous. Increasing demands for food by a growing human population increases the importance and urgency of understanding how microbiomes may be exploited to increase crop yields and reduce losses caused by disease. In addition, climate change effects may require novel approaches to overcoming abiotic stresses such as drought and salinity as well as new emerging diseases. This review discusses current knowledge on the formation and maintenance of root-associated microbial communities and plant-microbe interactions with a particular emphasis on the effect of microbe-microbe interactions on the shape of microbial communities at the root surface. Further, we discuss the potential for root microbiome modification to benefit agriculture and food production. PMID:26729479

  12. Plant root-microbe communication in shaping root microbiomes.

    Science.gov (United States)

    Lareen, Andrew; Burton, Frances; Schäfer, Patrick

    2016-04-01

    A growing body of research is highlighting the impacts root-associated microbial communities can have on plant health and development. These impacts can include changes in yield quantity and quality, timing of key developmental stages and tolerance of biotic and abiotic stresses. With such a range of effects it is clear that understanding the factors that contribute to a plant-beneficial root microbiome may prove advantageous. Increasing demands for food by a growing human population increases the importance and urgency of understanding how microbiomes may be exploited to increase crop yields and reduce losses caused by disease. In addition, climate change effects may require novel approaches to overcoming abiotic stresses such as drought and salinity as well as new emerging diseases. This review discusses current knowledge on the formation and maintenance of root-associated microbial communities and plant-microbe interactions with a particular emphasis on the effect of microbe-microbe interactions on the shape of microbial communities at the root surface. Further, we discuss the potential for root microbiome modification to benefit agriculture and food production.

  13. Influência do estado nutricional de minicepas no enraizamento de miniestacas de eucalipto Influence of the nutritional status of ministumps on the rooting of eucalypt minicuttings

    Directory of Open Access Journals (Sweden)

    Ana Catarina Monteiro Carvalho Mori da Cunha

    2009-08-01

    Full Text Available O enraizamento adventício de estacas é influenciado por fatores intrínsecos e extrínsecos do material vegetal. O conhecimento sobre o modo de ação desses fatores sobre o enraizamento é fundamental para o sucesso da produção de mudas por miniestaquia. Entre os fatores envolvidos no enraizamento, pode-se destacar a nutrição mineral, pois existe significativa relação entre ela e o enraizamento. No entanto, a importância de vários nutrientes nesse processo ainda não está totalmente esclarecida. Diante do exposto, o objetivo deste trabalho foi avaliar o grau de associação linear entre o estado nutricional das minicepas com o enraizamento de miniestacas de eucalipto. Foram utilizados dados da empresa CENIBRA, entre os quais se analisaram os de enraizamento de miniestacas e dos teores de nutrientes revelados por análises químicas dos tecidos foliares das minicepas. Os dados usados foram originados de minijardim clonal cultivado em leito de areia, com fertirrigação por gotejamento. Com esses dados, foram realizadas análises para avaliar a existência de correlação linear entre as concentrações de macro e micronutrientes nas minicepas e a taxa de enraizamento das miniestacas. Os resultados indicaram que a nutrição mineral desempenha papel importante no enraizamento adventício das miniestacas produzidas pelas minicepas, gerando respostas diferenciadas de acordo com o nutriente considerado. Os resultados evienciaram que a solução nutritiva aplicada no minijardim clonal deve ser específica para cada clone.The adventitious rooting of cuttings is influenced by intrinsic and extrinsic factors of the plant material. The knowledge about the way of the action of these factors upon rooting is essential for the success of the seedling production by minicuttings. Among the factors involved in rooting the mineral nutrition can be emphasized because there is a significant relation between it and rooting, but the importance of various

  14. 大针茅根系构型对草地退化的响应%Responses of the root architecture of Stipa grandis to grassland degradation

    Institute of Scientific and Technical Information of China (English)

    周艳松; 王立群; 张鹏; 梁金华; 王旭峰

    2011-01-01

    The study was conducted to investigate responses of root architecture of Stipa grandis grown under different grassland degradation levels (light, medium, high and extreme) in Xilin Gol League. The relative completed roots of S. grandis were collected by trenching and analyzed by using the root analysis system of WinRHIZO to determine total root length, root surface area, total root volume, root average diameter, number of root tips, number of furcation and average branching angle, number and length of first vertical root, number and length of first lateral root, number and length of secondary lateral root, number of adventitious root. The data obtained was analyzed by one-way ANOVA and principal component analysis. The results indicated that 1) the number of furcation, the surface area of root and the total length of root were the preferred indexes for analyzing S. grandis' variation to grassland degradation, while the number of furcation had the strongest explanation strength of the indexes to the variation. The cumulative contribution rate of the three root architecture indexes was 90.7%. 2) With the degradation development from light to extreme, the root architecture of S. grandis was obviously miniaturized. This phenomenon was especially obvious in medium degradation grassland. 3) The miniaturized root architecture of S. grandis eventually led to miniaturization of the entire plant, so the role of S. grandis as constructive species in the succession process of the community degradation was gradually weakened and finally replaced by other dominant species.%本研究对锡林郭勒典型草原区轻度、中度、重度和极度4个退化梯度草地中大针茅(Stipagrandis)根系构型进行研究。结果表明,1)根分叉数、根表面积和总根长3个参数是分析大针茅根系构型在不同退化程度草地中变化的主要指标,其中根分又数对该变化的解释力最强,3个参数的累积贡献率为90.7%;2

  15. Descendant root volume varies as a function of root type: estimation of root biomass lost during uprooting in Pinus pinaster

    OpenAIRE

    Danjon, Frédéric; Caplan, Joshua S.; Fortin, Mathieu; Meredieu, Céline

    2013-01-01

    Root systems of woody plants generally display a strong relationship between the cross-sectional area or cross-sectional diameter (CSD) of a root and the dry weight of biomass (DWd) or root volume (Vd) that has grown (i.e., is descendent) from a point. Specification of this relationship allows one to quantify root architectural patterns and estimate the amount of material lost when root systems are extracted from the soil. However, specifications of this relationship generally do not account ...

  16. How Can Science Education Foster Students' Rooting?

    Science.gov (United States)

    Østergaard, Edvin

    2015-01-01

    The question of how to foster rooting in science education points towards a double challenge; efforts to "prevent" (further) uprooting and efforts to "promote" rooting/re-rooting. Wolff-Michael Roth's paper discusses the uprooting/rooting pair of concepts, students' feeling of alienation and loss of fundamental sense of the…

  17. MES buffer affects Arabidopsis root apex zonation and root growth by suppressing superoxide generation in root apex

    Directory of Open Access Journals (Sweden)

    Tomoko eKagenishi

    2016-02-01

    Full Text Available In plants, growth of roots and root hairs is regulated by the fine cellular control of pH and reactive oxygen species. MES, 2-(N-morpholinoethanesulfonic acid as one of the Good’s buffers has broadly been used for buffering medium, and it is thought to suit for plant growth with the concentration at 0.1% (w/v because the buffer capacity of MES ranging pH 5.5-7.0 (for Arabidopsis, pH 5.8. However, many reports have shown that, in nature, roots require different pH values on the surface of specific root apex zones, namely meristem, transition zone and elongation zone. Despite the fact that roots always grow on a media containing buffer molecule, little is known about impact of MES on root growth. Here, we have checked the effects of different concentrations of MES buffer using growing roots of Arabidopsis thaliana. Our results show that 1% of MES significantly inhibited root growth, the number of root hairs and length of meristem, whereas 0.1% promoted root growth and root apex area (region spanning from the root tip up to the transition zone. Furthermore, superoxide generation in root apex disappeared at 1% of MES. These results suggest that MES disturbs normal root morphogenesis by changing the reactive oxygen species (ROS homeostasis in root apex.

  18. MES Buffer Affects Arabidopsis Root Apex Zonation and Root Growth by Suppressing Superoxide Generation in Root Apex.

    Science.gov (United States)

    Kagenishi, Tomoko; Yokawa, Ken; Baluška, František

    2016-01-01

    In plants, growth of roots and root hairs is regulated by the fine cellular control of pH and reactive oxygen species (ROS). MES, 2-(N-morpholino)ethanesulfonic acid as one of the Good's buffers has broadly been used for buffering medium, and it is thought to suit for plant growth with the concentration at 0.1% (w/v) because the buffer capacity of MES ranging pH 5.5-7.0 (for Arabidopsis, pH 5.8). However, many reports have shown that, in nature, roots require different pH values on the surface of specific root apex zones, namely meristem, transition zone, and elongation zone. Despite the fact that roots always grow on a media containing buffer molecule, little is known about impact of MES on root growth. Here, we have checked the effects of different concentrations of MES buffer using growing roots of Arabidopsis thaliana. Our results show that 1% of MES significantly inhibited root growth, the number of root hairs and length of meristem, whereas 0.1% promoted root growth and root apex area (region spanning from the root tip up to the transition zone). Furthermore, superoxide generation in root apex disappeared at 1% of MES. These results suggest that MES disturbs normal root morphogenesis by changing the ROS homeostasis in root apex. PMID:26925066

  19. Radiopacity of root filling materials

    International Nuclear Information System (INIS)

    A method for measuring the radiopacity of root filling materials is described. Direct measurements were made of the optic density values of the materials in comparison with a standard curve relating optic density to the thickness of an aluminium step wedge exposed simultaneously. By proper selection of film and conditions for exposure and development, it was possible to obtain a near-linear standard curve which added to the safety and reproducibility of the method. The technique of radiographic assessment was modified from clinical procedures in evaluating the obturation in radiographs, and it was aimed at detecting slits or voids between the dental wall and the filling material. This radiographic assessment of potensial leakage was compared with actual in vitro lekage of dye (basic fuchsin) into the roots of filled teeth. The result of the investigation show that root filling materials display a very wide range of radiopacity, from less than 3 mm to more than 12 mm of aluminium. It also seem that tooth roots that appear to be well obturated by radiographic evaluation, stand a good chance of beeing resistant to leakage in vitro, and that the type of filling material rather than its radiographic appearance, determines the susceptibility of the filled tooth to leakage in vitro. As an appendix the report contains a survey of radiopaque additives in root filling materials

  20. Root conditioning in periodontology — Revisited

    OpenAIRE

    Nanda, Tarun; Jain, Sanjeev; Kaur, Harjit; Kapoor, Daljit; Nanda, Sonia; Jain, Rohit

    2014-01-01

    Objective: Root surfaces of periodontitis-affected teeth are hypermineralized and contaminated with cytotoxic and other biologically active substances. To achieve complete decontamination of the tooth surfaces, various methods including root conditioning following scaling and root planning are present. The main objective of this article is to throw light on the different root conditioning agents used and the goals accomplished by root conditioning in the field of periodontology. Materials and...

  1. Role of Cytokinin and Auxin in Shaping Root Architecture: Regulating Vascular Differentiation, Lateral Root Initiation, Root Apical Dominance and Root Gravitropism

    OpenAIRE

    Aloni, R; ALONI, E.; Langhans, M.; ULLRICH, C. I.

    2006-01-01

    • Background and Aims Development and architecture of plant roots are regulated by phytohormones. Cytokinin (CK), synthesized in the root cap, promotes cytokinesis, vascular cambium sensitivity, vascular differentiation and root apical dominance. Auxin (indole-3-acetic acid, IAA), produced in young shoot organs, promotes root development and induces vascular differentiation. Both IAA and CK regulate root gravitropism. The aims of this study were to analyse the hormonal mechanisms that induce ...

  2. An Efficient Method for Adventitious Shoot Regeneration from Leaf and Stem-segment Explants of Russian Olive Elaeagnus angustifolia L.%采用俄罗斯橄榄叶片和茎段诱导产生不定芽的高效再生方法

    Institute of Scientific and Technical Information of China (English)

    卢松冲; 朱金启; 李杰; 张洪霞

    2011-01-01

    The establishment of an efficient adventitious shoot regeneration system from leaf discs and stem segments of one-year-old Russian olive ( Elaeagnus angustifolia L. ) was established. Shoot regeneration using leaf explants and stem segments was obtained on MS medium supplemented with different cytokinins viz., 6-benzyladenine (BA) and Zeatin (Zt), with combination of auxins viz. , naphthaleneacetic acid (NAA) and indole-3-butyric acid (IBA). MS + 0.5mg/L 6-BA + 0.2mg/L NAA was found to be a better combination for leaf regeneration, producing a maximum of 4.3 shoots per explant, whereas MS + 1. 0mg/L Zt +0.5mg/L NAA for stem-segment explants produced the highest number of multiple shoots (3.6) per explant. The regenerated shoots produced 100% rooting on 1/2 strength MS medium supplied with 0.5mg/L NAA. In vitro raised plantlets were successfully transferred to pots containing sterile soil: peat moss: sand ( 1 : 1 : 1 ) for acclimatization, and 77% of rooted plantlets survived under ex situ conditions. The currently employed regeneration protocol through leaf explants and stem segments facilitates germplasm conservation of this medicinally and ecologically important species besides providing a standardized regeneration protocol for genetic transformation studies in the future.%俄罗斯橄榄(Elaeagnus angustifolia L.)是一种具有很重要药用价值和生态意义的植物.以俄罗斯橄榄一年生幼苗的叶片和茎段为实验材料,探讨了细胞分裂素类(6-BA和Zt)和生长素类(NAA和IBA)两类激素不同组合以及不同配比对植株再生的影响,最后建立了一个高效的俄罗斯橄榄再生方法.结果表明,MS培养基+0.5 mg/L 6-BA+0.2 mg/L NAA更适合叶片的再生,平均每个外植体能产生多达4.3个不定芽;而在MS培养基+1.0 mg/L Zt+0.5 mg/L NAA的条件下,茎段外植体再生出来的不定芽最多可以达到平均3.6个;再生芽在含有0.5 mg/L NAA的1/2 MS培养基上生根率达到100%.体外再生苗移

  3. Capturing Arabidopsis Root Architecture Dynamics with root-fit Reveals Diversity in Responses to Salinity

    NARCIS (Netherlands)

    M.M. Julkowska; H.C.J. Hoefsloot; S. Mol; R. Feron; G.J. de Boer; M.A. Haring; C. Testerink

    2014-01-01

    The plant root is the first organ to encounter salinity stress, but the effect of salinity on root system architecture (RSA) remains elusive. Both the reduction in main root (MR) elongation and the redistribution of the root mass between MRs and lateral roots (LRs) are likely to play crucial roles i

  4. Facilitative root interactions in intercrops

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, H.; Jensen, E.S.

    2005-01-01

    Facilitation takes place when plants ameliorate the environment of their neighbours, and increase their growth and survival. Facilitation occurs in natural ecosystems as well as in agroecosystems. We discuss examples of facilitative root interactions in intercropped agroecosystems; including...... of root architecture, exudation of growth stimulating substances, and biofumigation. Facilitative root interactions are most likely to be of importance in nutrient poor soils and in low-input agroecosystems due to critical interspecific competition for plant growth factors. However, studies from more...... nitrogen transfer between legumes and non-leguminous plants, exploitation of the soil via mycorrhizal fungi and soil-plant processes which alter the mobilisation of plant growth resources such as through exudation of amino acids, extra-cellular enzymes, acidification, competition-induced modification...

  5. Descendant root volume varies as a function of root type: estimation of root biomass lost during uprooting in Pinus pinaster

    Directory of Open Access Journals (Sweden)

    Frédéric eDanjon

    2013-10-01

    Full Text Available Root systems of woody plants generally display a strong relationship between the cross-sectional area (CSA or cross-sectional diameter (CSD of a root and the dry weight of biomass (DWd or root volume (Vd that has grown (i.e., is descendent from that point. Specification of this relationship allows one to quantify root architectural patterns and estimate the amount of material lost when root systems are extracted from the soil. However, specifications of this relationship generally do not account for the fact that root systems are comprised of multiple types of roots. We assessed whether the relationship between CSD and Vd varies as a function of root type. Additionally, we sought to identify a more accurate and time-efficient method for estimating missing root volume than is currently available.We used a database that described the 3D root architecture of Pinus pinaster root systems (5, 12, or 19 yr from a stand. We determined the relationship between CSD and Vd for 10,000 root segments from intact root branches. Models were specified that did and did not account for root type. The relationships were then applied to the diameters of 11,000 broken root ends to estimate the volume of missing roots.CSD was nearly linearly related to the square root of Vd, but the slope of the curve varied greatly as a function of root type. Sinkers and deep roots tapered rapidly, as they were limited by available soil depth. Distal shallow roots tapered gradually, as they were less limited spatially. We estimated that younger trees lost an average of 17% of root volume when excavated, while older trees lost 4%. Missing volumes were smallest in the central parts of root systems and largest in distal shallow roots.The slopes of the curves for each root type are synthetic parameters that account for differentiation due to genetics, soil properties, or mechanical stimuli. Accounting for this differentiation is critical to estimating root loss accurately.

  6. Detrending bootstrap unit root tests

    OpenAIRE

    Smeekes, S.

    2009-01-01

    The role of detrending in bootstrap unit root tests is investigated. When bootstrapping, detrending must not only be done for the construction of the test statistic, but also in the first step of the bootstrap algorithm. It is argued that the two points should be treated separately. Asymptotic validity of sieve bootstrap ADF unit root tests is shown for test statistics based on full sample and recursive OLS and GLS detrending. It is also shown that the detrending method in the first step of t...

  7. Evaluation for Plant Regeneration Potential of Root Explants in Echinacea purpurea%松果菊根外植体植株再生能力的评价

    Institute of Scientific and Technical Information of China (English)

    Dahanayake NILANTHI; 赵福成; 杨跃生; 吴鸿

    2009-01-01

    为了评价松果菊Echinacea purpurea L.根外植体的再生能力,将从松果菊无菌小苗得到的根外植体和叶片以及叶柄外植体接种到含有不同种类和浓度的细胞分裂素和生长素的培养基上,诱导不定芽的再生.结果表明,在多数情况下,根外植体的再生能力显著高于叶片,和叶柄类似.0.3 mg/L的苄基腺嘌呤和0.01 mg/L的萘乙酸是诱导根外植体不定芽再生最合适的激素种类和质量浓度组合.根外植体培养的不定芽再生频率为100%,每个根外植体得到再生芽1.75个.当把这些由根再生的不定芽从母体组织切开并转移培养到含有0.01 mg/L萘乙酸的培养基后,很容易生根并成为完整的植株.可见根是组培快繁松果菊理想的外植体材料.%For evaluation of the plant regeneration potential of root explants, explants of root, leaf and petiole were taken from in vitro grown purple coneflower, Echinacea purpurea L. Plantlets and cultured on adventitious bud inducing media with different cytokinins and auxins at various concentrations. In most of the cases, the regeneration potential of root explants was much higher than that of leaf ones and similar to that of petiole explants, and a combination of 0.3 mg/L benzyladeine with 0.01 mg/L naphthaleneacetic acid was the most effective combination and concentrations for inducing adventitious bud regen-eration. Although the best result of bud regeneration was obtained from culture of petiole explants, a good result in regenera-tion rate of 100% and a high number of 1.75 buds per exphnt were obtained from culture of root explants. Buds regenerated from root explants initiated roots and became intact plants readily upon transfer to a medium containing 0.01 mg/L naphthale-neacetic acid. Results of the experiments indicated that root was an ideal explant source for rapid propagation by means of tis-sue culture in this plant species.

  8. New theories of root growth modelling

    Science.gov (United States)

    Landl, Magdalena; Schnepf, Andrea; Vanderborght, Jan; Huber, Katrin; Javaux, Mathieu; Bengough, A. Glyn; Vereecken, Harry

    2016-04-01

    In dynamic root architecture models, root growth is represented by moving root tips whose line trajectory results in the creation of new root segments. Typically, the direction of root growth is calculated as the vector sum of various direction-affecting components. However, in our simulations this did not reproduce experimental observations of root growth in structured soil. We therefore developed a new approach to predict the root growth direction. In this approach we distinguish between, firstly, driving forces for root growth, i.e. the force exerted by the root which points in the direction of the previous root segment and gravitropism, and, secondly, the soil mechanical resistance to root growth or penetration resistance. The latter can be anisotropic, i.e. depending on the direction of growth, which leads to a difference between the direction of the driving force and the direction of the root tip movement. Anisotropy of penetration resistance can be caused either by microscale differences in soil structure or by macroscale features, including macropores. Anisotropy at the microscale is neglected in our model. To allow for this, we include a normally distributed random deflection angle α to the force which points in the direction of the previous root segment with zero mean and a standard deviation σ. The standard deviation σ is scaled, so that the deflection from the original root tip location does not depend on the spatial resolution of the root system model. Similarly to the water flow equation, the direction of the root tip movement corresponds to the water flux vector while the driving forces are related to the water potential gradient. The analogue of the hydraulic conductivity tensor is the root penetrability tensor. It is determined by the inverse of soil penetration resistance and describes the ease with which a root can penetrate the soil. By adapting the three dimensional soil and root water uptake model R-SWMS (Javaux et al., 2008) in this way

  9. 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.

  10. Four cuspal maxillary second premolar with single root and three root canals: Case report

    Directory of Open Access Journals (Sweden)

    Parul Bansal

    2016-01-01

    Full Text Available Traditional configuration of maxillary second premolars has been described to have two cusps, one root and one or two root canals. The endodontic literature reports considerable anatomic aberrations in the root canal morphology of maxillary second premolar but the literature available on the variation in cuspal anatomy and its relationship to the root canal anatomy is sparse. The purpose of this clinical report was to describe the root and root canal configuration of a maxillary second premolar with four cusps.

  11. Comparative pharmacognostical variations in stem, true root and aerial root of Tinospora cordifolia willd

    OpenAIRE

    Rohit Ajith Gokarn; Supriya Gokarn; Galib; Harisha, C. R.; Biswajyoti Patgiri

    2014-01-01

    Context: Amrita (Tinospora cordifolia Willd.) an often used perennial climber used in different clinical conditions and various researches are useful in understanding its potential, but comparative pharmacognostical study of stem, true root and aerial root is not available till date. Root of Amrita is often used in folklore medicine. As true root is not abundantly available, aerial roots may be considered in the place of true root. Objective: The present study was designed to evaluate the sim...

  12. Four cuspal maxillary second premolar with single root and three root canals: Case report.

    Science.gov (United States)

    Bansal, Parul; Nikhil, Vineeta; Goyal, Ayush; Singh, Ritu

    2016-01-01

    Traditional configuration of maxillary second premolars has been described to have two cusps, one root and one or two root canals. The endodontic literature reports considerable anatomic aberrations in the root canal morphology of maxillary second premolar but the literature available on the variation in cuspal anatomy and its relationship to the root canal anatomy is sparse. The purpose of this clinical report was to describe the root and root canal configuration of a maxillary second premolar with four cusps. PMID:27563190

  13. [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.

  14. Disease notes - Bacterial root rot

    Science.gov (United States)

    Bacterial root rot initiated by lactic acid bacteria, particularly Leuconostoc, occurs every year in Idaho sugarbeet fields. Hot fall weather seems to make the problem worse. Although Leuconostoc initiates the rot, other bacteria and yeast frequently invade the tissue as well. The acetic acid bac...

  15. [Root arthrosis of the thumb].

    Science.gov (United States)

    Hautefeuille, P; Duquesnoy, B

    1991-12-15

    Root arthrosis of the thumb results from a degenerative lesion of the trapezometacarpal joint. It is particularly frequent in menopausal women. The often prolonged pain it produces sometimes raises therapeutic problems. Treatment is always medical at first, but when it fails several surgical operations will ensure permanent painlessness. PMID:1808686

  16. Contemporary root canal filling strategies

    NARCIS (Netherlands)

    A.T. Moinzadeh

    2016-01-01

    Currently, clinicians can choose from a wide range of root canal filling materials and techniques, some of which have been evaluated in this thesis. Methacrylate resin-based sealers suffer from polymerization shrinkage stresses. This limitation may partly be overcome by a two-step cementation proced

  17. Enraizamento de estacas de Sebastiania schottiana Müll. Arg. Rooting of Sebastiania schottiana Müll. Arg. cuttings

    Directory of Open Access Journals (Sweden)

    Eduardo Garcia Frassetto

    2010-12-01

    trial, basal, median and apical cuttings had their bases immersed in Orgasol® FTS at levels of 0, 5, 10 and 15mL L-1, for 1 minute. The experimental design was in random blocks, with three replicates and 20 cuttings per plot. At 75 days, the rooted cuttings percentage, the length and diameter of the longest root were evaluated. In a second trial, basal and median cuttings were treated for 0, 15, 30 and 45 minutes in 15mL L-1 of Orgasol® FTS. The experimental design was in random blocks, with three replicates of 20 cuttings per plot. At 150 day, the rooted cuttings percentage, dry roots mass and the length and diameter of the longest root were evaluated. In the first trial, higher levels of product was beneficial to rooting, it was observed the largets rooted cuttings percentage in the treatment with 15mL L-1 of product. In second trial, the higher rooting potential was observed in the basal and median cuttings treated by 45 minutes in 15mL L-1 of product. The use of orgasol® FTS promotes adventitious roots in Sebastiania schottiana cuttings.

  18. Investigation of VEGGIE Root Mat

    Science.gov (United States)

    Subbiah, Arun M.

    2013-01-01

    VEGGIE is a plant growth facility that utilizes the phenomenon of capillary action as its primary watering system. A cloth made of Meta Aramid fiber, known as Nomex is used to wick water up from a reservoir to the bottom of the plants roots. This root mat system is intended to be low maintenance with no moving parts and requires minimal crew interface time. Unfortunately, the water wicking rates are inconsistent throughout the plant life cycle, thus causing plants to die. Over-wicking of water occurs toward the beginning of the cycle, while under-wicking occurs toward the middle. This inconsistency of wicking has become a major issue, drastically inhibiting plant growth. The primary objective is to determine the root cause of the inconsistent wicking through experimental testing. Suspect causes for the capillary water column to break include: a vacuum effect due to a negative pressure gradient in the water reservoir, contamination of material due to minerals in water and back wash from plant fertilizer, induced air bubbles while using syringe refill method, and material limitations of Nomex's ability to absorb and retain water. Experimental testing will be conducted to systematically determine the cause of under and over-wicking. Pressure gages will be used to determine pressure drop during the course of the plant life cycle and during the water refill process. A debubbler device will be connected to a root mat in order to equalize pressure inside the reservoir. Moisture and evaporation tests will simultaneously be implemented to observe moisture content and wicking rates over the course of a plant cycle. Water retention tests will be performed using strips of Nomex to determine materials wicking rates, porosity, and absorptivity. Through these experimental tests, we will have a better understanding of material properties of Nomex, as well as determine the root cause of water column breakage. With consistent test results, a forward plan can be achieved to resolve

  19. Characterizing pathways by which gravitropic effectors could move from the root cap to the root of primary roots of Zea mays

    Science.gov (United States)

    Moore, R.; McClelen, C. E.

    1989-01-01

    Plasmodesmata linking the root cap and root in primary roots Zea mays are restricted to approx. 400 protodermal cells bordering approx. 110000 microns2 of the calyptrogen of the root cap. This area is less than 10% of the cross-sectional area of the root-tip at the cap junction. Therefore, gravitropic effectors moving from the root cap to the root can move symplastically only through a relatively small area in the centre of the root. Decapped roots are non-responsive to gravity. However, decapped roots whose caps are replaced immediately after decapping are strongly graviresponsive. Thus, gravicurvature occurs only when the root cap contacts the root, and symplastic continuity between the cap and root is not required for gravicurvature. Completely removing mucilage from the root tip renders the root non-responsive to gravity. Taken together, these data suggest that gravitropic effectors move apoplastically through mucilage from the cap to the root.

  20. Effects of Rooting Substrates on In Vitro Rooting of Anthurium andraeanum L. cv. Avanti

    Directory of Open Access Journals (Sweden)

    Wararat KEATMETHA

    2004-06-01

    Full Text Available A study was made of the effects of rooting substrates on in vitro rooting of Anthurium andraeanum L. cv. Avanti, orange flower. Initiation of root was attempted in several rooting substrates with modified ½ MS medium supplemented with 30 g/l sucrose. The cut end of the shoot was dipped in 2.5 g/l indole-3-butyric acid (IBA before insertion in substrates. After 4 weeks of culture, it was found that roots were markedly induced in 8 and 12 g/l agar with 86.67 and 73.33% in root induction rate, 14.62 and 12.41 mm in root length, with 3.54 and 3.91 roots in root number respectively. However, 93.33% of root induction rate with 3.00 roots, and 11.66 mm in root length were produced on medium containing 1.5 g/l phytagel while peat moss and vermiculite could induce rooting at 46.67% with 7.86 and 6.66 mm in length, with 1.00 and 1.86 roots respectively. Root could not be induced in sphagnum moss. Anatomical study of root showed no abnormality in all rooting substrates. The roots formed in high concentrations of agar at 12 and 16 g/l, 2.0 and 2.5 g/l phytagel, and peat moss were thicker than those formed in other rooting substrates. Especially, root formed in peat moss had the largest vascular diameter. However, roots formed in phytagel, peat moss, and vermiculite had more root hairs than those formed in agar substrate. Plantlets, rooted in peat moss and vermiculite, survived at 100% after acclimation in a mixture of soil and coconut husk.

  1. ANALGESIC ACTIVITY OF ROOT EXTRACT OF SOLANUM MELONGENA LINN ROOT

    Directory of Open Access Journals (Sweden)

    Srivastava Ashish

    2011-05-01

    Full Text Available The present study was aimed at Pharmacognostic study and biological evaluation of analgesic activity of plants roots. The roots of plants were studies for Pharmacognostic characteristics namely, morphology, microscopy, physicochemical parameters, which can be of utilized in identification/authentication of the plant and/or its roots in crude drug form. The preliminary phytochemical screening of the dry residue was carried out by the chemical test and thin layer chromatographic method. The preliminary phytochemical screening of dry residue showed the presence of Saponins, Alkaloids, Glycoside, and Flavonoids in various extracts. However most of the medicinally potential phytoconstituents were present in methanolic and aqueous extracts. The Hydroalcoholic extract was selected for Biological screening due to high alcoholic-soluble extractive value, high yield of successive alcoholic extract and TLC results. The analgesic screening was done using Hot plate method, Tail immersion methods and acetic acid induced in rats and mice. Hydroalcoholic extract was administered orally at the acute doses of 200mg/kg and 400mg/kg b.w. Several activities on these doses have already been reported. Both the doses showed significant (p<0.05 analgesic activity.

  2. Meromorphic iterative roots of linear fractional functions

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Iterative root problem can be regarded as a weak version of the problem of embedding a homeomorphism into a flow. There are many results on iterative roots of monotone functions. However, this problem gets more difficult in non-monotone cases. Therefore, it is interesting to find iterative roots of linear fractional functions (abbreviated as LFFs), a class of non-monotone functions on R. In this paper, iterative roots of LFFs are studied on C. An equivalence between the iterative functional equation for non-constant LFFs and the matrix equation is given. By means of a method of finding matrix roots, general formulae of all meromorphic iterative roots of LFFs are obtained and the precise number of roots is also determined in various cases. As applications, we present all meromorphic iterative roots for functions z and 1/z.

  3. Rhizosphere biophysics and root water uptake

    Science.gov (United States)

    Carminati, Andrea; Zarebanadkouki, Mohsen; Ahmed, Mutez A.; Passioura, John

    2016-04-01

    The flow of water into the roots and the (putative) presence of a large resistance at the root-soil interface have attracted the attention of plant and soil scientists for decades. Such resistance has been attributed to a partial contact between roots and soil, large gradients in soil matric potential around the roots, or accumulation of solutes at the root surface creating a negative osmotic potential. Our hypothesis is that roots are capable of altering the biophysical properties of the soil around the roots, the rhizosphere, facilitating root water uptake in dry soils. In particular, we expect that root hairs and mucilage optimally connect the roots to the soil maintaining the hydraulic continuity across the rhizosphere. Using a pressure chamber apparatus we measured the relation between transpiration rate and the water potential difference between soil and leaf xylem during drying cycles in barley mutants with and without root hairs. The samples were grown in well structured soils. At low soil moistures and high transpiration rates, large drops in water potential developed around the roots. These drops in water potential recovered very slowly, even after transpiration was severely decreased. The drops in water potential were much bigger in barley mutants without root hairs. These mutants failed to sustain high transpiration rates in dry conditions. To explain the nature of such drops in water potential across the rhizosphere we performed high resolution neutron tomography of the rhizosphere of the barleys with and without root hairs growing in the same soil described above. The tomograms suggested that the hydraulic contact between the soil structures was the highest resistance for the water flow in dry conditions. The tomograms also indicate that root hairs and mucilage improved the hydraulic contact between roots and soil structures. At high transpiration rates and low water contents, roots extracted water from the rhizosphere, while the bulk soil, due its

  4. PHARMACOGNOSTIC EVALUATION OF KALANCHOE PINNATA ROOTS

    OpenAIRE

    Quazi Majaz A.; Sayyed Nazim; Shaikh Siraj; Shaikh Afsar; Patel M. Siddik

    2011-01-01

    The plant Kalanchoe pinnata is widely used in ayurvedic system of medicine as astringent, analgesic, carminative and also useful in diarrhea and vomiting. It is naturalized throughout the hot and moist parts of India. And lots of phytochemical and pharmacological work has done on leaves of plant but the root part is not focused. Hence we have selected roots for pharmacognostic analysis which will support further studies on the root. In this first roots are subjected to microscopic and macrosc...

  5. Histological analysis of the callogenesis and organogenesis from root segments of Curcuma zedoaria Roscoe

    Directory of Open Access Journals (Sweden)

    Marcia O. Mello

    2001-06-01

    Full Text Available Callus was induced from root segments taken from in vitro grown plants of Curcuma zedoaria Roscoe. The explants were cultured on agar-solidified Murashige and Skoog medium supplemented with 13.4muM of alpha-naphthaleneacetic acid and 2.2muM of 6-benzylaminopurine at 25ºC in the dark. Histological analysis revealed that callus was formed from the hypertrophied cortical parenchyma cells of the explant. Some of these cells underwent division while the surrounding cells accumulated starch. Callus was capable of shoot bud regeneration after 70 days when it was transfered to liquid medium of the same composition. After 30 days in liquid medium, buds developed from nodular structures. The adventitious shoots developed extensive root systems when they were placed on agar-solidified Murashige and Skoog medium without growth regulators at 25º C in the light. The establishment of these plantlets in soil was about 95%.Calo de Curcuma zedoaria Roscoe foram induzidos a partir de segmentos de raízes de plantas cultivadas in vitro. Os explantes foram inoculados em meio de Murashige & Skoog solidificado com ágar e suplementado com 13,4miM de ácido alfa-naftaleno acético e 2,2miM de 6-benzilaminopurina e mantidos no escuro a 25°C. As análises histológicas realizadas revelaram que os callus eram formados a partir de células hipertrofiadas do parênquima cortical do explante. Algumas destas células entravam em divisão, enquanto as células vizinhas a estas acumulavam amido. Após 70 dias, calos transferidos para meio de Murashige & Skoog líquido de mesma composição, eram capazes de regenerar plantas. Após 30 dias em meio líquido, gemas se desenvolveram de estruturas nodulares. Estas gemas adventíceas formaram um abundante sistema radicular quando transferidas para meio de Murashige & Skoog solidificado com ágar, sem regulador de crescimento e mantidas a 25°C na luz. A taxa de sobrevivência das plantas foi de 95%.

  6. Root Cause Analysis, Part 2: STERILE COMPOUNDING.

    Science.gov (United States)

    Cabaleiro, Joe; Jackson, Kathleen

    2016-01-01

    When an adverse event or near miss occurs in a pharmacy, eliminating the root cause to prevent recurrence is critically important. Addressing the root cause of the problem reduces the recurrence of putting patients and the pharmacy at risk. This article proposes a method for performing Root Cause Analysis applicable to sterile compounding. PMID:27323421

  7. Root Cause Analysis: Methods and Mindsets.

    Science.gov (United States)

    Kluch, Jacob H.

    This instructional unit is intended for use in training operations personnel and others involved in scram analysis at nuclear power plants in the techniques of root cause analysis. Four lessons are included. The first lesson provides an overview of the goals and benefits of the root cause analysis method. Root cause analysis techniques are covered…

  8. Automatic schema evolution in Root

    International Nuclear Information System (INIS)

    ROOT version 3 (spring 2001) supports automatic class schema evolution. In addition this version also produces files that are self-describing. This is achieved by storing in each file a record with the description of all the persistent classes in the file. Being self-describing guarantees that a file can always be read later, its structure browsed and objects inspected, also when the library with the compiled code of these classes is missing. The schema evolution mechanism supports the frequent case when multiple data sets generated with many different class versions must be analyzed in the same session. ROOT supports the automatic generation of C++ code describing the data objects in a file

  9. Retention of Root Canal Posts

    DEFF Research Database (Denmark)

    Sahafi, A; Benetti, Ana Raquel; Flury, S;

    2015-01-01

    The aim of this study was to investigate the effect of the cement film thickness of a zinc phosphate or a resin cement on retention of untreated and pretreated root canal posts. Prefabricated zirconia posts (CosmoPost: 1.4 mm) and two types of luting cements (a zinc phosphate cement [DeTrey Zinc...... received tribochemical silicate coating according to the manufacturer's instructions. Posts were then luted in the prepared root canals (n=30 per group). Following water storage at 37°C for seven days, retention of the posts was determined by the pull-out method. Irrespective of the luting cement......, pretreatment with tribochemical silicate coating significantly increased retention of the posts. Increased cement film thickness resulted in decreased retention of untreated posts and of pretreated posts luted with zinc phosphate cement. Increased cement film thickness had no influence on retention...

  10. Quantum Roots in Geometry: I

    CERN Document Server

    Wanas, M I

    2003-01-01

    In the present work, it is shown that the geometerization philosophy has not been exhausted. Some quantum roots are already built in non-symmetric geometries. Path equations in such geometries give rise to spin-gravity interaction. Some experimental evidences (the results of the COW-experiment) indicate the existence of this interaction. It is shown that the new quantum path equations could account for the results of the COW-experiment. Large scale applications, of the new path equations, admitted by such geometries, give rise to tests for the existence of this interaction on the astrophysical and cosmological scales. As a byproduct, it is shown that the quantum roots appeared explicitly, in the path equations, can be diffused in the whole geometry using a parameterization scheme.

  11. Automatic Schema Evolution in Root

    Institute of Scientific and Technical Information of China (English)

    ReneBrun; FonsRademakers

    2001-01-01

    ROOT version 3(spring 2001) supports automatic class schema evolution.In addition this version also produces files that are self-describing.This is achieved by storing in each file a record with the description of all the persistent classes in the file.Being self-describing guarantees that a file can always be read later,its structure browsed and objects inspected.also when the library with the compiled code of these classes is missing The schema evolution mechanism supports the frequent case when multiple data sets generated with many different class versions must be analyzed in the same session.ROOT supports the automatic generation of C++ code describing the data objects in a file.

  12. Contemporary root canal filling strategies

    OpenAIRE

    Moinzadeh, A.T.

    2016-01-01

    Currently, clinicians can choose from a wide range of root canal filling materials and techniques, some of which have been evaluated in this thesis. Methacrylate resin-based sealers suffer from polymerization shrinkage stresses. This limitation may partly be overcome by a two-step cementation procedure. This alternative placement technique results in an increase and homogenization of the adhesion of the material to intraradicular dentin. Subsequent research should aim at developing sealers wi...

  13. 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

  14. Phene synergism between root hair length and basal root growth angle for phosphorus acquisition.

    Science.gov (United States)

    Miguel, Magalhaes Amade; Postma, Johannes Auke; Lynch, Jonathan Paul

    2015-04-01

    Shallow basal root growth angle (BRGA) increases phosphorus acquisition efficiency by enhancing topsoil foraging because in most soils, phosphorus is concentrated in the topsoil. Root hair length and density (RHL/D) increase phosphorus acquisition by expanding the soil volume subject to phosphorus depletion through diffusion. We hypothesized that shallow BRGA and large RHL/D are synergetic for phosphorus acquisition, meaning that their combined effect is greater than the sum of their individual effects. To evaluate this hypothesis, phosphorus acquisition in the field in Mozambique was compared among recombinant inbred lines of common bean (Phaseolus vulgaris) having four distinct root phenotypes: long root hairs and shallow basal roots, long root hairs and deep basal roots, short root hairs and shallow basal roots, and short root hairs and deep basal roots. The results revealed substantial synergism between BRGA and RHL/D. Compared with short-haired, deep-rooted phenotypes, long root hairs increased shoot biomass under phosphorus stress by 89%, while shallow roots increased shoot biomass by 58%. Genotypes with both long root hairs and shallow roots had 298% greater biomass accumulation than short-haired, deep-rooted phenotypes. Therefore, the utility of shallow basal roots and long root hairs for phosphorus acquisition in combination is twice as large as their additive effects. We conclude that the anatomical phene of long, dense root hairs and the architectural phene of shallower basal root growth are synergetic for phosphorus acquisition. Phene synergism may be common in plant biology and can have substantial importance for plant fitness, as shown here.

  15. Popliteal Artery Adventitial Cyst: case report and literature review Cisto Adventicial de Artéria Poplítea: relato de caso e revisão da literatura

    Directory of Open Access Journals (Sweden)

    Angelo Frankini

    2012-06-01

    Full Text Available The popliteal artery adventitial cyst is not a commonly studied pathology due to the rarity of its occurrence, however it is a disease that should always be considered as a differential diagnosis in the presence of a young patient who complains of claudication of the lower limbs. Because of its importance, the aim of this paper is to review some concepts about this disease based on a case report, analyzing its occurrence, etiopathology, clinical manifestations, diagnosis and treatment options.O cisto adventicial de artéria poplítea é uma patologia pouco estudada na literatura devido à raridade de sua ocorrência, porém é uma situação que serve como diagnóstico diferencial sempre que estivermos diante de um paciente jovem com claudicação. Em virtude da sua importância, este trabalho tem como objetivo revisar alguns aspectos acerca do assunto, baseado em um relato de caso, analisando sua ocorrência, etiopatogenia, manifestações clínicas, métodos de diagnóstico e opções de tratamento.

  16. Use of PCR-based assays for the detection of the adventitious agent porcine circovirus type 1 (PCV1) in vaccines, and for confirming the identity of cell substrates and viruses used in vaccine production.

    Science.gov (United States)

    Kumar, Deepak; Beach, Nathan M; Meng, Xiang-Jin; Hegde, Nagendra R

    2012-01-01

    Safety and quality are important issues for vaccines. Whereas reversion to virulence poses a safety risk with live attenuated vaccines, the potential for the presence of adventitious agents is also an issue of vaccine quality. The recent detection or porcine circovirus type 1 (PCV1) in human vaccines has further highlighted the importance of quality control in vaccine production. The purpose of this study was to use a novel conventional PCR to detect PCV1, and subsequently screen materials used in the manufacture of vaccines at Bharat Biotech International Limited, India. The genome or gene fragments of PCV1 were not detected in any of the vaccines and materials tested, including the live attenuated rotavirus vaccine candidate ROTAVAC(®). Further, the identity of the cells and the viruses used as starting materials in the manufacture of these vaccines was confirmed by species-specific PCR or virus-specific RT-PCR, and no cross-contamination was detected in any case. The methods can be applied for regular in-house quality control screening of raw materials and seeds/banks, as well as formulated vaccines.

  17. Printing Values In Interactive ROOT

    CERN Document Server

    Perovic, Boris

    2015-01-01

    This project report summarizes the work I have been performing during the past twelve weeks as a Summer Student intern working on ROOT project in the SFT group, PH department, under the supervision of Axel Naumann and Danilo Piparo. One of the widely requested features for ROOT was improved interactive shell experience as well as improved printing of object values. Solving this issue was the goal of this project. Primarily, we have enabled printing of the collections. Secondly, we have unified the printing interface, making it much more robust and extendible. Thirdly, we have implemented printing of nested collections in a flexible and user-friendly manner. Finally, we have added an interactive mode, allowing for paginated output. At the beginning of the report, ROOT is presented with examples of where it is used and how important it is. Then, the motivation behind the project is elaborated, by presenting the previous state of the software package and its potential for improvement. Further, the process in wh...

  18. ROOT Status and Future Developments

    CERN Document Server

    Brun, R; Canal, P; Rademakers, Fons; Goto, Masaharu; Canal, Philippe; Brun, Rene

    2003-01-01

    In this talk we will review the major additions and improvements made to the ROOT system in the last 18 months and present our plans for future developments. The additons and improvements range from modifications to the I/O sub-system to allow users to save and restore objects of classes that have not been instrumented by special ROOT macros, to the addition of a geometry package designed for building, browsing, tracking and visualizing detector geometries. Other improvements include enhancements to the quick analysis sub-system (TTree::Draw()), the addition of classes that allow inter-file object references (TRef, TRefArray), better support for templated and STL classes, amelioration of the Automatic Script Compiler and the incorporation of new fitting and mathematical tools. Efforts have also been made to increase the modularity of the ROOT system with the introduction of more abstract interfaces and the development of a plug-in manager. In the near future, we intend to continue the development of PROOF and...

  19. Application of glutathione to roots selectively inhibits cadmium transport from roots to shoots in oilseed rape

    Science.gov (United States)

    Nakamura, Shin-ichi

    2013-01-01

    Glutathione is a tripeptide involved in various aspects of plant metabolism. This study investigated the effects of the reduced form of glutathione (GSH) applied to specific organs (source leaves, sink leaves, and roots) on cadmium (Cd) distribution and behaviour in the roots of oilseed rape plants (Brassica napus) cultured hydroponically. The translocation ratio of Cd from roots to shoots was significantly lower in plants that had root treatment of GSH than in control plants. GSH applied to roots reduced the Cd concentration in the symplast sap of root cells and inhibited root-to-shoot Cd translocation via xylem vessels significantly. GSH applied to roots also activated Cd efflux from root cells to the hydroponic solution. Inhibition of root-to-shoot translocation of Cd was visualized, and the activation of Cd efflux from root cells was also shown by using a positron-emitting tracer imaging system (PETIS). This study investigated a similar inhibitory effect on root-to-shoot translocation of Cd by the oxidized form of glutathione, GSSG. Inhibition of Cd accumulation by GSH was abolished by a low-temperature treatment. Root cells of plants exposed to GSH in the root zone had less Cd available for xylem loading by actively excluding Cd from the roots. Consequently, root-to-shoot translocation of Cd was suppressed and Cd accumulation in the shoot decreased. PMID:23364937

  20. Root caries, root surface restorations and lifestyle factors in adult Danes

    DEFF Research Database (Denmark)

    Christensen, Lisa Bøge; Jensen, Allan Bardow; Ekstrand, Kim;

    2015-01-01

    and restored root surface lesions, respectively. RESULTS: The prevalence of active root caries was 4%, while 26% displayed restored root surfaces. The sugar intake was not related to root caries. A multivariate logistic regression analysis revealed that, in subjects aged 45 or over, smoking and wearing....... In addition, oral health education should focus on the possible risks of smoking and a high alcohol intake....

  1. Comparative pharmacognostical variations in stem, true root and aerial root of Tinospora cordifolia willd

    Directory of Open Access Journals (Sweden)

    Rohit Ajith Gokarn

    2014-01-01

    Full Text Available Context: Amrita (Tinospora cordifolia Willd. an often used perennial climber used in different clinical conditions and various researches are useful in understanding its potential, but comparative pharmacognostical study of stem, true root and aerial root is not available till date. Root of Amrita is often used in folklore medicine. As true root is not abundantly available, aerial roots may be considered in the place of true root. Objective: The present study was designed to evaluate the similarities between stem, true root, aerial root and to substantiate the use of aerial root in place of true root. Materials and Methods: Macroscopic, microscopic and histochemical study of fresh samples of stem, aerial root and true root of Amrita was carried out. Results: The distinctive character of stem shows dominant pericyclic fibre and pith. True root is devoid of pith where as aerial root has condensed pith consisting of lignified parenchyma. Conclusion: Specific individual characters of stem and true root and similar characters of aerial root were evident.

  2. The quality of root fillings remaining in mandibular incisors after root-end cavity preparation

    NARCIS (Netherlands)

    Wu, MK; de Schwartz, FBC; van der Sluis, LWM; Wesselink, PR

    2001-01-01

    Aim The aim of this study was to determine the quality of root fillings remaining in mandibular incisors after root-end resection and root-end cavity preparation. Methodology Roots of 40 mandibular incisors. 12 mm in length. were divided into two groups and instrumented using a balanced force techni

  3. A New Anatomically Based Nomenclature for the Roots and Root Canals—Part 1: Maxillary Molars

    Directory of Open Access Journals (Sweden)

    Jojo Kottoor

    2012-01-01

    Full Text Available Numerous terminologies have been employed in the dental literature to describe the roots and root canal systems of maxillary molars. This multiplicity in naming of roots and canals makes the reader susceptible to misinterpretation and confusion. No consensus thus far has been arrived at for defining the names of roots and root canals in maxillary molars, including their various morphological aberrations. The anatomical relation of roots and their root canals were identified and were subsequently named based on definite sets of criteria. A new method for identification and naming of roots and root canal anatomy in maxillary molars, based on their root and canal relationship, was formulated and is presented in this paper. The nomenclature makes certain essential modifications to the traditional approach to accommodate naming of the various aberrations presented in the maxillary molars. A simple, yet extensive, nomenclature system has been proposed that appropriately names the internal and external morphology of maxillary molars.

  4. Light as stress factor to plant roots - case of root halotropism.

    Science.gov (United States)

    Yokawa, Ken; Fasano, Rossella; Kagenishi, Tomoko; Baluška, František

    2014-01-01

    Despite growing underground, largely in darkness, roots emerge to be very sensitive to light. Recently, several important papers have been published which reveal that plant roots not only express all known light receptors but also that their growth, physiology and adaptive stress responses are light-sensitive. In Arabidopsis, illumination of roots speeds-up root growth via reactive oxygen species-mediated and F-actin dependent process. On the other hand, keeping Arabidopsis roots in darkness alters F-actin distribution, polar localization of PIN proteins as well as polar transport of auxin. Several signaling components activated by phytohormones are overlapping with light-related signaling cascade. We demonstrated that the sensitivity of roots to salinity is altered in the light-grown Arabidopsis roots. Particularly, light-exposed roots are less effective in their salt-avoidance behavior known as root halotropism. Here we discuss these new aspects of light-mediated root behavior from cellular, physiological and evolutionary perspectives.

  5. Penis-root perception of Koro patients.

    Science.gov (United States)

    Chowdhury, A N

    1991-07-01

    Koro is an acute anxiety reaction in which the perception of decreased penis length because of intra-abdominal traction is the main feature. This study attempts to explore the penis-root perception of the Koro patients by a graphomotor projective test--the Draw-a-penis Test (DAPT). This controlled DAPT investigation shows that Koro patients perceived the penis as a detached organ with root-boundary definiteness as evidenced from their close penis-root perception. They also displayed reduced volumetric perception of penis-root than the normal subjects. These perceptual deviations in penis-root image are discussed in relation to their Koro vulnerability.

  6. Five Roots Pattern of Median Nerve Formation

    Directory of Open Access Journals (Sweden)

    Konstantinos Natsis

    2016-04-01

    Full Text Available An unusual combination of median nerve’s variations has been encountered in a male cadaver during routine educational dissection. In particular, the median nerve was formed by five roots; three roots originated from the lateral cord of the brachial plexus joined individually the median nerve’s medial root. The latter (fourth root was united with the lateral (fifth root of the median nerve forming the median nerve distally in the upper arm and not the axilla as usually. In addition, the median nerve was situated medial to the brachial artery. We review comprehensively the relevant variants, their embryologic development and their potential clinical applications.

  7. Asteroidal Quadruples in non Rooted Path Graphs

    Directory of Open Access Journals (Sweden)

    Gutierrez Marisa

    2015-11-01

    Full Text Available A directed path graph is the intersection graph of a family of directed subpaths of a directed tree. A rooted path graph is the intersection graph of a family of directed subpaths of a rooted tree. Rooted path graphs are directed path graphs. Several characterizations are known for directed path graphs: one by forbidden induced subgraphs and one by forbidden asteroids. It is an open problem to find such characterizations for rooted path graphs. For this purpose, we are studying in this paper directed path graphs that are non rooted path graphs. We prove that such graphs always contain an asteroidal quadruple.

  8. 苦荞麦毛状根的诱导研究%Study on Hairy-roots Induction of Fagopyrum tataricum Gaertn

    Institute of Scientific and Technical Information of China (English)

    孙雁霞; 王跃华; 陈燕; 张红玉; 赵钢; 邬晓勇

    2012-01-01

    利用发根农杆菌Ri1601浸染苦养植物预培养2d的叶片外植体,经不同时间的共培养和除菌培养后获得毛状根.经硅胶薄层色谱板检测表明,发根农杆菌Ri1601和苦养叶片上未经转化产生的不定根都不含有冠瘿碱;而经发根农杆菌Ri1601遗传转化后所产生的毛状根有冠瘿碱的存在.因此,可确定苦荞叶片上产生的毛状根为发根农杆菌Ri1601转化所得.建立了用发根农杆菌Ri1601诱导苦荞植物叶片产生毛状根的有效方法.%The Hairy-roots can be obtained by inoculating two-day-precultured leaf explants of Fagopyrum tataricum Gaertn with Agrobaterium rhizogenes Ril601. The silicon thin layer chromatogra-phy (TLC) tests showed that the adventitious roots produced by leaves of Fagopyrum tataricum Gaertn and Agrobaterium rhizogenes Ril601 do not contain crown gall alkali. On the other hand, the hairy roots which were produced by Agrobaterium rhizogenes Ril601-mediated genetic transformation of Fagopyrum tataricum Gaertn leaves have crown gall alkali. Therefore, it can be determined that the hairy roots from leaves of Fagopyrum tataricum Gaertn were produced by Agrobaterium rhizogenes Ril601-mediated transformation. Due to these, the different factors were designed to examine for their effects on hairy-roots induction and growth. The effective methodology of hairy-roots induction by Agrobaterium rhizogenes was established and provided a foundation for industrial production of active components from Fagopyrum tataricum Gaertn.

  9. Involvement of Arabidopsis thaliana phospholipase Dzeta2 in root hydrotropism through the suppression of root gravitropism.

    OpenAIRE

    Taniguchi, Yukimi Y; Taniguchi, Masatoshi; Tsuge, Tomohiko; Oka, Atsuhiro; Aoyama, Takashi

    2010-01-01

    Root hydrotropism is the phenomenon of directional root growth toward moisture under water-deficient conditions. Although physiological and genetic studies have revealed the involvement of the root cap in the sensing of moisture gradients, and those of auxin and abscisic acid (ABA) in the signal transduction for asymmetric root elongation, the overall mechanism of root hydrotropism is still unclear. We found that the promoter activity of the Arabidopsis phospholipase Dzeta2 gene (PLDzeta2) wa...

  10. Assessment of the wetting behavior of three different root canal sealers on root canal dentin

    OpenAIRE

    Muralidhar Tummala; Veeramachaneni Chandrasekhar; A Shashi Rashmi; Kundabala, M; Vasudev Ballal

    2012-01-01

    Aim: The objective of the present study was to evaluate and compare the wetting behavior of three different root canal sealers on the root canal dentin surface treated with irrigants and their combination. Materials and Methods: Decoronation and apical third resections of 27 extracted single-rooted human mandibular premolars were done. The roots were then split longitudinally into two halves, and randomly assigned into three treatment groups (n=18). The root dentin surfaces in Group1, Gro...

  11. Optimal root arrangement of cereal crops

    Science.gov (United States)

    Jung, Yeonsu; Park, Keunhwan; Kim, Ho-Young

    2015-11-01

    The plant root absorbs water from the soil and supplies it to the rest part of the plant. It consists of a number of root fibers, through whose surfaces water uptake occurs. There is an intriguing observation that for most of cereal crops such as maize and wheat, the volume density of root in the soil declines exponentially as a function of depth. To understand this empirical finding, we construct a theoretical model of root water uptake, where mass transfer into root surface is modeled just as heat flux around a fin. Agreement between the theoretically predicted optimal root distribution in vertical direction and biological data supports the hypothesis that the plant root has evolved to achieve the optimal water uptake in competition with neighbors. This study has practical implication in the agricultural industry as well as optimal design of water transport networks in both micro- and macroscales. Department of Mechanical and Aerospace Engineering, Seoul National University, Seoul 08826, Korea.

  12. Root cap removal increases root penetration resistance in maize (Zea mays L).

    Science.gov (United States)

    Iijima, Morio; Higuchi, Toshifumi; Barlow, Peter W; Bengough, A Glyn

    2003-09-01

    The root cap assists the passage of the root through soil by means of its slimy mucilage secretion and by the sloughing of its outer cells. The root penetration resistance of decapped primary roots of maize (Zea mays L. cv. Mephisto) was compared with that of intact roots in loose (dry bulk density 1.0 g cm-3; penetration resistance 0.06 MPa) and compact soil (1.4 g cm-3; penetration resistance 1.0 MPa), to evaluate the contribution of the cap to decreasing the impedance to root growth. Root elongation rate and diameter were the same for decapped and intact roots when the plants were grown in loose soil. In compacted soil, however, the elongation rate of decapped roots was only about half that of intact roots, whilst the diameter was 30% larger. Root penetration resistances of intact and decapped seminal axis were 0.31 and 0.52 MPa, respectively, when the roots were grown in compacted soil. These results indicated that the presence of a root cap alleviates much of the mechanical impedance to root penetration, and enables roots to grow faster in compacted soils.

  13. 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.

  14. Xanthones from Garcinia propinqua Roots.

    Science.gov (United States)

    Meesakul, Pornphimol; Pansanit, Acharavadee; Maneerat, Wisanu; Sripisut, Tawanun; Ritthiwigrom, Thunwadee; Machana, Theeraphan; Cheenpracha, Sarot; Laphookhieo, Surat

    2016-01-01

    Phytochemical investigation of Garcinia propinqua roots led to the isolation and identification of a new xanthone, doitunggarcinone D (1), together with 15 known compounds (2-16). Their structures were elucidated by intensive analysis of spectroscopic data. Compounds 3, 6, 7, 14, 15 and 16 exhibited strong antibacterial activity against Bacillus subtilis TISTR 088 with MIC values in the range of 1-4 µg/mL. Compounds 3, 7, 10 and 14 also showed good antibacterial activity against B. cereus TISTR 688 with MIC values ranging from 4-8 µg/mL. PMID:26996028

  15. Morphometric data of canine sacral nerve roots with reference to electrical sacral root stimulation.

    Science.gov (United States)

    Rijkhoff, N J; Koldewijn, E L; d'Hollosy, W; Debruyne, F M; Wijkstra, H

    1996-01-01

    Experiments to investigate restoration of lower urinary tract control by electrical stimulation of the sacral nerve roots are mostly performed on dogs, yet little morphometric data (such as canine root and fiber diameter distributions) are available. The aim of this study was to acquire morphometric data of the intradural canine sacral dorsal and ventral roots (S1-S3). Cross-sections of sacral roots of two beagle dogs were analyzed using a light microscope and image processing software. The cross-sectional area of each root was measured. The diameters of the fibers and the axons in the cross-sections of the S2 and S3 roots were measured and used to construct nerve fiber diameter frequency distribution histograms. The results show a unimodal diameter distribution for the dorsal roots and a bimodal distribution for the ventral roots. In addition the average ratio g of the axon diameter to fiber diameter was calculated for each root. PMID:8732990

  16. Patterns in soil fertility and root herbivory interact to influence fine-root dynamics.

    Science.gov (United States)

    Stevens, Glen N; Jones, Robert H

    2006-03-01

    Fine-scale soil nutrient enrichment typically stimulates root growth, but it may also increase root herbivory, resulting in trade-offs for plant species and potentially influencing carbon cycling patterns. We used root ingrowth cores to investigate the effects of microsite fertility and root herbivory on root biomass in an aggrading upland forest in the coastal plain of South Carolina, USA. Treatments were randomly assigned to cores from a factorial combination of fertilizer and insecticide. Soil, soil fauna, and roots were removed from the cores at the end of the experiment (8-9 mo), and roots were separated at harvest into three diameter classes. Each diameter class responded differently to fertilizer and insecticide treatments. The finest roots (root biomass, were the only ones to respond significantly to both treatments, increasing when fertilizer and when insecticide were added (each P root-feeding insects have a strong influence on root standing crop with stronger herbivore impacts on finer roots and within more fertile microsites. Thus, increased vulnerability to root herbivory is a potentially significant cost of root foraging in nutrient-rich patches.

  17. PATTERNS IN SOIL FERTILITY AND ROOT HERBIVORY INTERACT TO INFLUENCE FINE-ROOT DYNAMICS.

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, Glen, N.; Jones, Robert, H.

    2006-03-01

    Fine-scale soil nutrient enrichment typically stimulates root growth, but it may also increase root herbivory, resulting in trade-offs for plant species and potentially influencing carbon cycling patterns. We used root ingrowth cores to investigate the effects of microsite fertility and root herbivory on root biomass in an aggrading upland forest in the coastal plain of South Carolina, USA. Treatments were randomly assigned to cores from a factorial combination of fertilizer and insecticide. Soil, soil fauna, and roots were removed from the cores at the end of the experiment (8–9 mo), and roots were separated at harvest into three diameter classes. Each diameter class responded differently to fertilizer and insecticide treatments. The finest roots (,1.0 mm diameter), which comprised well over half of all root biomass, were the only ones to respond significantly to both treatments, increasing when fertilizer and when insecticide were added (each P , 0.0001), with maximum biomass found where the treatments were combined (interaction term significant, P , 0.001). These results suggest that root-feeding insects have a strong influence on root standing crop with stronger herbivore impacts on finer roots and within more fertile microsites. Thus, increased vulnerability to root herbivory is a potentially significant cost of root foraging in nutrient-rich patches.

  18. A statistical approach to root system classification.

    Directory of Open Access Journals (Sweden)

    Gernot eBodner

    2013-08-01

    Full Text Available Plant root systems have a key role in ecology and agronomy. In spite of fast increase in root studies, still there is no classification that allows distinguishing among distinctive characteristics within the diversity of rooting strategies. Our hypothesis is that a multivariate approach for plant functional type identification in ecology can be applied to the classification of root systems. We demonstrate that combining principal component and cluster analysis yields a meaningful classification of rooting types based on morphological traits. The classification method presented is based on a data-defined statistical procedure without a priori decision on the classifiers. Biplot inspection is used to determine key traits and to ensure stability in cluster based grouping. The classification method is exemplified with simulated root architectures and morphological field data. Simulated root architectures showed that morphological attributes with spatial distribution parameters capture most distinctive features within root system diversity. While developmental type (tap vs. shoot-borne systems is a strong, but coarse classifier, topological traits provide the most detailed differentiation among distinctive groups. Adequacy of commonly available morphologic traits for classification is supported by field data. Three rooting types emerged from measured data, distinguished by diameter/weight, density and spatial distribution respectively. Similarity of root systems within distinctive groups was the joint result of phylogenetic relation and environmental as well as human selection pressure. We concluded that the data-define classification is appropriate for integration of knowledge obtained with different root measurement methods and at various scales. Currently root morphology is the most promising basis for classification due to widely used common measurement protocols. To capture details of root diversity efforts in architectural measurement

  19. Towards understanding tree root profiles: simulating hydrologically optimal strategies for root distribution

    Directory of Open Access Journals (Sweden)

    M. T. van Wijk

    2001-01-01

    Full Text Available In this modelling study differences in vertical root distributions measured in four contrasting forest locations in the Netherlands were investigated. Root distributions are seen as a reflection of the plant’s optimisation strategy, based on hydrological grounds. The 'optimal' root distribution is defined as the one that maximises the water uptake from the root zone over a period of ten years. The optimal root distributions of four forest locations with completely different soil physical characteristics are calculated using the soil hydrological model SWIF. Two different model configurations for root interactions were tested: the standard model configuration in which one single root profile was used (SWIF-NC, and a model configuration in which two root profiles compete for the same available water (SWIF-C. The root profiles were parameterised with genetic algorithms. The fitness of a certain root profile was defined as the amount of water uptake over a simulation period of ten years. The root profiles of SWIF-C were optimised using an evolutionary game. The results showed clear differences in optimal root distributions between the various sites and also between the two model configurations. Optimisation with SWIF-C resulted in root profiles that were easier to interpret in terms of feasible biological strategies. Preferential water uptake in wetter soil regions was an important factor for interpretation of the simulated root distributions. As the optimised root profiles still showed differences with measured profiles, this analysis is presented, not as the final solution for explaining differences in root profiles of vegetation but as a first step using an optimisation theory to increase understanding of the root profiles of trees. Keywords: forest hydrology, optimisation, roots

  20. The Difference between the Micronutrients Content of Seeding's Root and Root Hair in Several Plant Species

    OpenAIRE

    Yamakawa, Takeo; Okuda, Naoko; Taira, Kenjiro

    2008-01-01

    It was reported in soybean that the content of Fe and Co microelements of the root hair invaded by rhizobium during the process of nodule formation was higher than that of the root. To confirm this point, a supplementary experiment was carried out using several applicable plants, soybeans, lupine, pea, corn and pumpkin. Root hair was separated in liquid nitrogen from the roots of those seedlings. The separated root hair of 20mg, or the residual root of 200mg was digested in a microwave wet...

  1. Seasonal changes of whole root system conductance by a drought-tolerant grape root system

    OpenAIRE

    Alsina, Maria Mar; Smart, David R.; Bauerle, Taryn; de Herralde, Felicidad; Biel, Carme; Stockert, Christine; Negron, Claudia; Save, Robert

    2010-01-01

    The role of root systems in drought tolerance is a subject of very limited information compared with above-ground responses. Adjustments to the ability of roots to supply water relative to shoot transpiration demand is proposed as a major means for woody perennial plants to tolerate drought, and is often expressed as changes in the ratios of leaf to root area (A L:A R). Seasonal root proliferation in a directed manner could increase the water supply function of roots independent of total root...

  2. Root canal treatment of bilateral three-rooted maxillary first premolars

    Directory of Open Access Journals (Sweden)

    Bhavana Gandhi

    2012-01-01

    Full Text Available In endodontics, several anatomic variations occur in teeth, both externally and in the internal root morphology, which play a very significant role in the diagnosis and treatment outcome. A thorough knowledge of the root canal anatomy, careful interpretation of the angled radiographs, proper endodontic access cavity preparation, and exploration of the root canal are the prerequisites for endodontic success. In a maxillary first premolar, it is rare to find extra roots and canals, and the aim of the present article is to report a case about the successful diagnosis and clinical management of bilateral three-rooted maxillary first premolars, with three independent root canals.

  3. Rooting of cuttings of vanilla plant (Orchidaceae / Enraizamento de estacas da baunilheira (Orchidaceae

    Directory of Open Access Journals (Sweden)

    Aparecida Gomes de Araujo

    2009-07-01

    Full Text Available The vanilla plant (Vanilla planifolia could have a higher commercial production but there are problems in the efficiency of propagation. The present work was conducted with the aim of studying the effect of different substrates, in the adventitious rooting of cuttings taken at five heights in the plant stem. The cuttings were 20cm long and had two buds and one leaf and were planted in: 1 Liquid medium formed by Clark’s nutrient added of 2.5mg L-1 of IBA placed in plastic foam box with a capacity of 1.5L lined inside with transparent plastic bag and lidded with proper lid. 2 Solid substrate formed by the mixture of sand, carbonized rice husk, soil and cured cow manure in equal proportions of volume, they being placed in rigid polypropylene with a capacity of 0.28L. 3 Pre-rooting of the cuttings in liquid medium (20 days before planting, and later transferred into seedling tubes containing solid substrate. The cuttings planted in the solid substrate were maintained under intermittent mist condition controlled by a timer. After 90 days, the percentage of rooting was of 98-100%, regardless of the treatment. Larger and more vigorous sproutings were obtained from cuttings planted directly into solid substrate. Adventitious rooting of cuttings and formation of new vanilla cuttings occurred, when the cuttings were obtained from position P2 (ranging between 20 to 40cm in stem height and planted in solid substrate in greenhouse with intermittent misting system. A baunilheira (Vanilla planifolia é uma planta pouco explorada comercialmente, devido ao emprego de tecnologias de baixa eficiência para a produção de mudas. Assim sendo, realizou-se o presente trabalho com o objetivo de estudar o efeito de diferentes substratos, no enraizamento adventício de estacas retiradas de diferentes posições na planta. Estacas com 20cm de comprimento, duas gemas e uma folha, tomadas na haste da planta, em cinco posições subseqüentes, a partir do ápice caulinar

  4. Systems approaches to study root architecture dynamics

    Directory of Open Access Journals (Sweden)

    Candela eCuesta

    2013-12-01

    Full Text Available The plant root system is essential for providing anchorage to the soil, supplying minerals and water, and synthesizing metabolites. It is a dynamic organ modulated by external cues such as environmental signals, water and nutrients availability, salinity and others. Lateral roots are initiated from the primary root post-embryonically, after which they progress through discrete developmental stages which can be independently controlled, providing a high level of plasticity during root system formation.Within this review, main contributions are presented, from the classical forward genetic screens to the more recent high-throughput approaches, combined with computer model predictions, dissecting how lateral roots and thereby root system architecture is established and developed.

  5. Unit roots, nonlinearities and structural breaks

    DEFF Research Database (Denmark)

    Haldrup, Niels; Kruse, Robinson; Teräsvirta, Timo;

    One of the most influential research fields in econometrics over the past decades concerns unit root testing in economic time series. In macro-economics much of the interest in the area originate from the fact that when unit roots are present, then shocks to the time series processes have a...... persistent effect with resulting policy implications. From a statistical perspective on the other hand, the presence of unit roots has dramatic implications for econometric model building, estimation, and inference in order to avoid the so-called spurious regression problem. The present paper provides a...... selective review of contributions to the field of unit root testing over the past three decades. We discuss the nature of stochastic and deterministic trend processes, including break processes, that are likely to affect unit root inference. A range of the most popular unit root tests are presented and...

  6. Winter Wheat Root Growth and Nitrogen Relations

    DEFF Research Database (Denmark)

    Rasmussen, Irene Skovby

    Root growth is an essential parameter regarding nitrogen (N) uptake efficiency, as more and deeper roots may improve the uptake from deeper soil layers and reduce nitrate leaching losses. During this PhD project, it was studied how different agronomic practices influence root growth and N relations...... in winter wheat (Triticum aestivum L). Field experiments on the effect of sowing date, N fertilization and cultivars were conducted on a sandy loam soil in Taastrup, Denmark. The root studies were conducted by means of the minirhizotron method. Also, a field experiment on the effect of defoliation and N...... fertilization was conducted in Canberra, Australia. Here the root studies were done by means of the core-break method and root washing....

  7. Regeneración de brotes adventicios en hojas de guayaba (Psidium guajava L. cultivadas in vitro Adventitious shoot regeneration from in vitro cultured leaves of guava (Psidium guava L.

    Directory of Open Access Journals (Sweden)

    Trujillo Sánchez Reinaldo

    2004-12-01

    Full Text Available La regeneración de brotes adventicios es una etapa clave para la aplicación de las técnicas de ingeniería gené­tica. El presente trabajo tuvo como objetivo el desarrollo de un procedimiento para la regeneración de brotes por organogénesis a partir de hojas de microesquejes o brotes de guayaba (Psidium guajava L. cultivados in vi­tro. Para ello se estudiaron algunos de los principales factores que afectan la regeneración de brotes, tales como la concentración de reguladores del crecimiento (citoquinina, el estado fisiológico del explante y la he­rida. En todos los experimentos se utilizaron como explantes hojas de vitroplantas de guayaba de la variedad Enana Roja Cubana EEA18-40 de diferentes subcultivos. El mejor resultado se alcanzó con una concentración de 0,75 mg/L de 6-bencilaminopurina como suplemento hormonal del medio MS. Se comprobó que para las hojas provenientes de microesquejes con mayor número de subcultivo y tomadas de la parte inferior de los brotes, el potencial morfogenético disminuye significativamente (p60% y el mayor número de brotes por explante promedio (>3 se alcanzó al realizar varias heridas en forma de punteaduras en el nervio central de las hojas. Este protocolo de regeneración constituye una importante herramienta que puede ser empleada para futuros estudios de transformación genética en esta especie. Palabras clave: cultivo de tejidos, explantes de hoja, reguladores de crecimiento, organogénesis, guayaba.Adventitious regeneration is a key step in the application of genetic engineering to the breeding programs of plants. In this work a method for adventitious shoot regeneration from leaves of micropropagated guava shoots has been developed and some of main factors to affect the shoot regeneration like, concentration of plant growth regulators (citoquinine, physiological state of explants and the wound are studied. Leaves from guava in vitro cultured of variety Cuban Red Dwarf 18-40 was used

  8. Springback and diagravitropism in Merit corn roots

    Science.gov (United States)

    Kelly, M. O.; Leopold, A. C.

    1992-01-01

    Dark-treated Merit corn (Zea mays L.) roots are diagravitropic and lose curvature upon withdrawal of the gravity stimulus (springback). Springback was not detected in a variety of corn that is orthogravitropic in the dark, nor in Merit roots in which tropistic response was enhanced either with red light or with abscisic acid. A possible interpretation is that springback may be associated with a weak growth response of diagravitropic roots.

  9. Modelling root distribution and nitrogen uptake

    OpenAIRE

    Pedersen, Anders; Thorup-kristensen, Kristian

    2004-01-01

    Plant soil and atmosphere models are commonly used to predict crop yield and environmental consequence. Such models often include complex modelling modules for water movement, soil organic matter turnover and, above ground plant growth. However, the root modelling in these models are often very simple, partly due to a limited access to experimental data. We present a two-dimensional model for root growth and proliferation. The model focuses on annual crops, and attempt to model root gro...

  10. Root doctors as providers of primary care.

    Science.gov (United States)

    Stitt, V J

    1983-07-01

    Physicians in primary care recognize that as many as 65 percent of the patients seen in their offices are there for psychological reasons. In any southern town with a moderate population of blacks, there are at least two "root doctors." These root doctors have mastered the power of autosuggestion and are treating these patients with various forms of medication and psychological counseling. This paper updates the practicing physician on root doctors who practice primary care.

  11. Root phenology in a changing climate.

    Science.gov (United States)

    Radville, Laura; McCormack, M Luke; Post, Eric; Eissenstat, David M

    2016-06-01

    Plant phenology is one of the strongest indicators of ecological responses to climate change, and altered phenology can have pronounced effects on net primary production, species composition in local communities, greenhouse gas fluxes, and ecosystem processes. Although many studies have shown that aboveground plant phenology advances with warmer temperatures, demonstration of a comparable association for belowground phenology has been lacking because the factors that influence root phenology are poorly understood. Because roots can constitute a large fraction of plant biomass, and root phenology may not respond to warming in the same way as shoots, this represents an important knowledge gap in our understanding of how climate change will influence phenology and plant performance. We review studies of root phenology and provide suggestions to direct future research. Only 29% of examined studies approached root phenology quantitatively, strongly limiting interpretation of results across studies. Therefore, we suggest that researchers emphasize quantitative analyses in future phenological studies. We suggest that root initiation, peak growth, and root cessation may be under different controls. Root initiation and cessation may be more constrained by soil temperature and the timing of carbon availability, whereas the timing of peak root growth may represent trade-offs among competing plant sinks. Roots probably do not experience winter dormancy in the same way as shoots: 89% of the studies that examined winter phenology found evidence of growth during winter months. More research is needed to observe root phenology, and future studies should be careful to capture winter and early season phenology. This should be done quantitatively, with direct observations of root growth utilizing rhizotrons or minirhizotrons. PMID:26931171

  12. Characterization of Pearl Millet Root Architecture and Anatomy Reveals Three Types of Lateral Roots.

    Science.gov (United States)

    Passot, Sixtine; Gnacko, Fatoumata; Moukouanga, Daniel; Lucas, Mikaël; Guyomarc'h, Soazig; Ortega, Beatriz Moreno; Atkinson, Jonathan A; Belko, Marème N; Bennett, Malcolm J; Gantet, Pascal; Wells, Darren M; Guédon, Yann; Vigouroux, Yves; Verdeil, Jean-Luc; Muller, Bertrand; Laplaze, Laurent

    2016-01-01

    Pearl millet plays an important role for food security in arid regions of Africa and India. Nevertheless, it is considered an orphan crop as it lags far behind other cereals in terms of genetic improvement efforts. Breeding pearl millet varieties with improved root traits promises to deliver benefits in water and nutrient acquisition. Here, we characterize early pearl millet root system development using several different root phenotyping approaches that include rhizotrons and microCT. We report that early stage pearl millet root system development is characterized by a fast growing primary root that quickly colonizes deeper soil horizons. We also describe root anatomical studies that revealed three distinct types of lateral roots that form on both primary roots and crown roots. Finally, we detected significant variation for two root architectural traits, primary root lenght and lateral root density, in pearl millet inbred lines. This study provides the basis for subsequent genetic experiments to identify loci associated with interesting early root development traits in this important cereal. PMID:27379124

  13. Measurements of water uptake of maize roots: the key function of lateral roots

    Science.gov (United States)

    Ahmed, M. A.; Zarebanadkouki, M.; Kroener, E.; Kaestner, A.; Carminati, A.

    2014-12-01

    Maize (Zea mays L.) is one of the most important crop worldwide. Despite its importance, there is limited information on the function of different root segments and root types of maize in extracting water from soils. Therefore, the aim of this study was to investigate locations of root water uptake in maize. We used neutron radiography to: 1) image the spatial distribution of maize roots in soil and 2) trace the transport of injected deuterated water (D2O) in soil and roots. Maizes were grown in aluminum containers (40×38×1 cm) filled with a sandy soil. When the plants were 16 days old, we injected D2O into selected soil regions containing primary, seminal and lateral roots. The experiments were performed during the day (transpiring plants) and night (not transpiring plants). The transport of D2O into roots was simulated using a new convection-diffusion numerical model of D2O transport into roots. By fitting the observed D2O transport we quantified the diffusional permeability and the water uptake of the different root segments. The maize root architecture consisted of a primary root, 4-5 seminal roots and many lateral roots connected to the primary and seminal roots. Laterals emerged from the proximal 15 cm of the primary and seminal roots. Water uptake occurred primarily in lateral roots. Lateral roots had the highest diffusional permeability (9.4×10-7), which was around six times higher that the diffusional permeability of the old seminal segments (1.4×10-7), and two times higher than the diffusional permeability of the young seminal segments (4.7×10-7). The radial flow of D2O into the lateral (6.7×10-5 ) was much higher than in the young seminal roots (1.1×10-12). The radial flow of D2O into the old seminal was negligible. We concluded that the function of the primary and seminal roots was to collect water from the lateral roots and transport it to the shoot. A maize root system with lateral roots branching from deep primary and seminal roots would be

  14. Power Efficient Division and Square Root Unit

    DEFF Research Database (Denmark)

    Liu, Wei; Nannarelli, Alberto

    2012-01-01

    Although division and square root are not frequent operations, most processors implement them in hardware to not compromise the overall performance. Two classes of algorithms implement division or square root: digit-recurrence and multiplicative (e.g., Newton-Raphson) algorithms. Previous work...... shows that division and square root units based on the digit-recurrence algorithm offer the best tradeoff delay-area-power. Moreover, the two operations can be combined in a single unit. Here, we present a radix-16 combined division and square root unit obtained by overlapping two radix-4 stages...

  15. Designing new interfaces for ROOT data processing

    CERN Document Server

    Vuorinen, Kalle Elmer

    2016-01-01

    ROOT is a C++ framework for data analysis provided with a Python interface (PyRoot). ROOT is used in every Large Hadron Collider experiment. This project presents a way of reading ROOT TTree by using a new class called DataFrame, which allows the usage of cache and functional chains. Reading TTrees in Python has been quite slow compared to the C++ way of doing it and for this reason we also bring the possibility to read them with just-in-time (JIT) compiled C++ code, using another new Python class called TreeReader.

  16. Deriving the unit hydrograph by root selection

    Science.gov (United States)

    Turner, J. E.; Dooge, J. C. I.; Bree, T.

    1989-09-01

    De Laine's method of deriving the unit hydrograph from the common roots of polynomials corresponding to different storms is used as a basis for proposing a new procedure in which the unit hydrograph roots can be selected from among the polynomial roots for the runoff of a single storm. The selection is made on the basis that the complex unit hydrograph roots form a characteristic "skew circle" pattern when plotted on an Argand diagram. The application of the procedure to field data is illustrated for both a single-peaked and a double-peaked event.

  17. Devil's claw root: ulcers and gastrointestinal bleeding?

    Science.gov (United States)

    2013-12-01

    Harpagophytum procumbens, or devil's claw, is an African plant whose root is used to relieve minor joint symptoms. Several cases of gastrointestinal bleeding associated with the use of devil's claw root have been reported. A systematic review of the adverse effects of devil's claw root in about 20 randomised, double-blind, placebo-controlled clinical trials showed mainly gastrointestinal effects: gastralgia and dyspepsia. In practice, devil's claw root exposes patients to the risk of sometimes serious upper gastrointestinal disorders, yet has no established efficacy beyond a placebo effect. It is best avoided. PMID:24600731

  18. ROOT TEMPERATURE EFFECT ON ROOT HYDRAULIC RESISTANCE IN CUCUMBER (CUCUMIS SATIVUS L.) AND FIGLEAF GOURD (CUCURBITA FICIFOLIA B.) PLANTS

    OpenAIRE

    Yoshida, Satoshi; Eguchi, Hiromi

    1990-01-01

    The effect of root temperature on total root resistance (hydraulic resistance in a whole root system) was examined in detached whole root systems of cucumber and figleaf gourd plants by applying the suction of 80kPa in root temperature region of 8 to 32℃. The total root resistances in both species became higher at lower root temperatures. From the fact that radial root resistance is about 80% of total root resistance, it could be conceivable that the temperature effect on the total root resis...

  19. ROOT HYDRAULIC CONDUCTIVITY AND PHOTOSYNTHETIC CAPACITY OF EUCALYPT CLONAL CUTTINGS WITH ROOT MALFORMATION INDUCTIONS

    Directory of Open Access Journals (Sweden)

    Fábio Afonso Mazzei Moura de Assis Figueiredo

    2014-06-01

    Full Text Available http://dx.doi.org/10.5902/1980509814566The gain reduction of wood biomass in trees has been assigned to root deformations even in the nursery phase. The objective of this work was the evaluation of the root system hydraulic conductivity, gas exchanges and photochemical efficiency of eucalypt clonal cuttings with and without root deformation inductions. The treatments were: 1 operational cuttings without root malformation inductions (grown according to the used methodology of Fibria Cellulose S.A.; 2 root deformation inductions. These inductions did not promote decrease in the root volume. However, the deformations brought reduction of the root system hydraulic conductivity. Lower photosynthetic rates were also observed along the day in the cuttings in the root deformed cuttings. This decreasing rate is connected to stomatal and non stomatal factors.

  20. Variations of fine root diameter with root order in Manchurian ash and Dahurian larch plantations

    Institute of Scientific and Technical Information of China (English)

    WANG Xiangrong; WANG Zhengquan; HAN Youzhi; GU Jiacun; GUO Dali; MEI Li

    2007-01-01

    Fine root lifespan and turnover play an important role in carbon allocation and nutrient cycling in forest ecosystems.Fine roots are typically defined as less than 1 or 2mm in diameter.However,when categorizing roots by this diameter size,the position of an individual root on the complex lateral branching pattern has often been ignored,and our knowledge about relationships between branching order and root function thus remains limited.More recently,studies on root survivals found that longevity was remarkably different in the same branching level due to diameter variations.The objectives of this study were:(1) To examine variations of fine root diameter from the first-to fifth-orders in Fraxinus mandshurica Rupr and Larix gmelinii Rupr roots;and (2) To reveal how the season,soil nutrient,and water availability affect root diameter in different branch order in two species.This study was conducted at Maoershan Forest Research Station (45°21'-45°25'N,127°30'-127°34'E) owned by Northeast Forestry University in Harbin,northeast China.Both F.mandshurica and L.gmelinii were planted in 1986.In each plantation,fine roots of two species by sampling up to five fine root branch orders three times during the 2003 growing season from two soil depths (i.e.,0-10 and 10-20 cm)were obtained.The results showed that average diameters of fine roots were significantly different among the five branch orders.The first-order had the thinner roots and the fifth order had the thickest roots,the diameter increasing regularly with the ascending branch orders in both species.If the diameter of fine roots was defined as being smaller than 0.5 mm,the first three orders ofF.mandshurica roots and the first two orders of L.gmelinii roots would be included in the fine root population.The diameter ranges of the fine roots from first-order to fifth-order were 0.15-0.58,0.18-0.70,0.26-1.05,0.36-1.43,and 0.71-2.96 mm for F.mandshurica,and 0.17-0.76,0.23-1.02,0.26-1.10,0.38-1.77,and 0.84-2.80 mm for L

  1. Plant root research: the past, the present and the future

    OpenAIRE

    Lux, Alexander; Rost, Thomas L.

    2012-01-01

    This special issue is dedicated to root biologists past and present who have been exploring all aspects of root structure and function with an extensive publication record going over 100 years. The content of the Special Issue on Root Biology covers a wide scale of contributions, spanning interactions of roots with microorganisms in the rhizosphere, the anatomy of root cells and tissues, the subcellular components of root cells, and aspects of metal accumulation and stresses on root function ...

  2. Genetic ablation of root cap cells in Arabidopsis

    OpenAIRE

    Tsugeki, Ryuji; Fedoroff, Nina V.

    1999-01-01

    The root cap is increasingly appreciated as a complex and dynamic plant organ. Root caps sense and transmit environmental signals, synthesize and secrete small molecules and macromolecules, and in some species shed metabolically active cells. However, it is not known whether root caps are essential for normal shoot and root development. We report the identification of a root cap-specific promoter and describe its use to genetically ablate root caps by directing root cap-specific expression of...

  3. Root tip-dependent, active riboflavin secretion by Hyoscyamus albus hairy roots under iron deficiency

    OpenAIRE

    Higa, Ataru; Miyamoto, Erika; Rahman, Laiq ur; Kitamura, Yoshie

    2008-01-01

    Hyoscyamus albus hairy roots with/without an exogenous gene (11 clones) were established by inoculation of Agrobacterium rhizogenes. All clones cultured under iron deficient condition secreted riboflavin from root tips into the culture medium and the productivity depended on the number and size of root tips among the clones, although the addition of sucrose was essential for riboflavin production. A decline of pH was observed before riboflavin production and root development using either a ro...

  4. Effect of Root Moisture Content and Diameter on Root Tensile Properties

    OpenAIRE

    Yuanjun Yang; Lihua Chen; Ning Li; Qiufen Zhang

    2016-01-01

    The stabilization of slopes by vegetation has been a topical issue for many years. Root mechanical characteristics significantly influence soil reinforcement; therefore it is necessary to research into the indicators of root tensile properties. In this study, we explored the influence of root moisture content on tensile resistance and strength with different root diameters and for different tree species. Betula platyphylla, Quercus mongolica, Pinus tabulaeformis, and Larix gmelinii, the most ...

  5. Malformations of the tooth root in humans

    Directory of Open Access Journals (Sweden)

    Hans Ulrich eLuder

    2015-10-01

    Full Text Available The most common root malformations in humans arise from either developmental disorders of the root alone or disorders of radicular development as part of a general tooth dysplasia. The aim of this review is to relate the characteristics of these root malformations to potentially disrupted processes involved in radicular morphogenesis. Radicular morphogenesis proceeds under the control of Hertwig's epithelial root sheath (HERS which determines the number, length, and shape of the root, induces the formation of radicular dentin, and participates in the development of root cementum. Formation of HERS at the transition from crown to root development appears to be very insensitive to adverse effects, with the result that rootless teeth are extremely rare. In contrast, shortened roots as a consequence of impaired or prematurely halted apical growth of HERS constitute the most prevalent radicular dysplasia which occurs due to trauma and unknown reasons as well as in association with dentin disorders. While odontoblast differentiation inevitably stops when growth of HERS is arrested, it seems to be unaffected even in cases of severe dentin dysplasias such as regional odontodysplasia and dentin dysplasia type I. As a result radicular dentin formation is at least initiated and progresses for a limited time. The only condition affecting cementogenesis is hypophosphatasia which disrupts the formation of acellular cementum through an inhibition of mineralization. A process particularly susceptible to adverse effects appears to be the formation of the furcation in multirooted teeth. Impairment or disruption of this process entails taurodontism, single-rooted posterior teeth, and misshapen furcations. Thus even though many characteristics of human root malformations can be related to disorders of specific processes involved in radicular morphogenesis, precise inferences as to the pathogenesis of these dysplasias are hampered by the still limited knowledge on

  6. Fine root production at drained peatland sites

    Energy Technology Data Exchange (ETDEWEB)

    Finer, L. [Finnish Forest Research Inst. (Finland). Joensuu Research Station; Laine, J. [Helsinki Univ. (Finland). Dept. of Forest Ecology

    1996-12-31

    The preliminary results of the Finnish project `Carbon balance of peatlands and climate change` show that fine roots play an important role in carbon cycling on peat soils. After drainage the roots of mire species are gradually replaced by the roots of trees and other forest species. Pine fine root biomass reaches a maximum level by the time of crown closure, some 20 years after drainage on pine mire. The aim of this study is to compare the results of the sequential coring method and the ingrowth bag method used for estimating fine root production on three drained peatland sites of different fertility. The results are preliminary and continuation to the work done in the study Pine root production on drained peatlands, which is part of the Finnish project `Carbon cycling on peatlands and climate change`. In this study the fine root biomass was greater on the poor site than on the rich sites. Pine fine root production increased with the decrease in fertility. Root turnover and the production of field layer species were greater on the rich sites than on the poor site. The results suggested that the in growth bag method measured more root activity than the magnitude of production. More than two growing seasons would have been needed to balance the root dynamics in the in growth bags with the surrounding soil. That time would probably have been longer on the poor site than on the rich ones and longer for pine and field layer consisting of dwarf shrubs than for field layer consisting of sedge like species and birch. (11 refs.)

  7. Assessment of the nonoperated root after apical surgery of the other root in mandibular molars

    DEFF Research Database (Denmark)

    Kraus, Riccardo D; von Arx, Thomas; Gfeller, David;

    2015-01-01

    INTRODUCTION: If a surgical approach is chosen to treat a multirooted tooth affected by persistent periapical pathosis, usually only the affected roots are operated on. The present study assessed the periapical status of the nonoperated root 5 years after apical surgery of the other root in mandi...

  8. X-ray computed tomography uncovers root-root interactions: quantifying spatial relationships between interacting root systems in three dimensions

    Directory of Open Access Journals (Sweden)

    Alexander Martin Paya

    2015-04-01

    Full Text Available Research in the field of plant biology has recently demonstrated that inter- and intra-specific interactions belowground can dramatically alter root growth. Our aim was to answer questions related to the effect of inter- vs. intra-specific interactions on the growth and utilization of undisturbed space by fine roots within three dimensions (3D using micro X-ray computed tomography. To achieve this, Populus tremuloides (quaking aspen and Picea mariana (black spruce seedlings were planted into containers as either solitary individuals, or inter-/intra-specific pairs, allowed to grow for two months, and 3D metrics developed in order to quantify their use of belowground space. In both aspen and spruce, inter-specific root interactions produced a shift in the vertical distribution of the root system volume, and deepened the average position of root tips when compared to intra-specifically growing seedlings. Inter-specific interactions also increased the minimum distance between root tips belonging to the same root system. There was no effect of belowground interactions on the radial distribution of roots, or the directionality of lateral root growth for either species. In conclusion, we found that significant differences were observed more often when comparing controls (solitary individuals and paired seedlings (inter- or intra-specific, than when comparing inter- and intra-specifically growing seedlings. This would indicate that competition between neighboring seedlings was more responsible for shifting fine root growth in both species than was neighbor identity. However, significant inter- vs. intra-specific differences were observed, which further emphasizes the importance of biological interactions in competition studies.

  9. Coupling root architecture and pore network modeling - an attempt towards better understanding root-soil interactions

    Science.gov (United States)

    Leitner, Daniel; Bodner, Gernot; Raoof, Amir

    2013-04-01

    Understanding root-soil interactions is of high importance for environmental and agricultural management. Root uptake is an essential component in water and solute transport modeling. The amount of groundwater recharge and solute leaching significantly depends on the demand based plant extraction via its root system. Plant uptake however not only responds to the potential demand, but in most situations is limited by supply form the soil. The ability of the plant to access water and solutes in the soil is governed mainly by root distribution. Particularly under conditions of heterogeneous distribution of water and solutes in the soil, it is essential to capture the interaction between soil and roots. Root architecture models allow studying plant uptake from soil by describing growth and branching of root axes in the soil. Currently root architecture models are able to respond dynamically to water and nutrient distribution in the soil by directed growth (tropism), modified branching and enhanced exudation. The porous soil medium as rooting environment in these models is generally described by classical macroscopic water retention and sorption models, average over the pore scale. In our opinion this simplified description of the root growth medium implies several shortcomings for better understanding root-soil interactions: (i) It is well known that roots grow preferentially in preexisting pores, particularly in more rigid/dry soil. Thus the pore network contributes to the architectural form of the root system; (ii) roots themselves can influence the pore network by creating preferential flow paths (biopores) which are an essential element of structural porosity with strong impact on transport processes; (iii) plant uptake depend on both the spatial location of water/solutes in the pore network as well as the spatial distribution of roots. We therefore consider that for advancing our understanding in root-soil interactions, we need not only to extend our root models

  10. Rapid phenotyping of alfalfa root system architecture

    Science.gov (United States)

    Root system architecture (RSA) influences the capacity of an alfalfa plant for symbiotic nitrogen fixation, nutrient uptake and water use efficiency, resistance to frost heaving, winterhardiness, and some pest and pathogen resistance. However, we currently lack a basic understanding of root system d...

  11. 33 CFR 117.1095 - Root River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Root River. 117.1095 Section 117.1095 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Wisconsin § 117.1095 Root River. (a) The draw of the Main...

  12. Roots, plant production and nutrient use efficiency.

    NARCIS (Netherlands)

    Willigen, de P.; Noordwijk, van M.

    1987-01-01

    The role of roots in obtaining high crop production levels as well as a high nutrient use efficiency is discussed. Mathematical models of diffusion and massflow of solutes towards roots are developed for a constant daily uptake requirement. Analytical solutions are given for simple and more complica

  13. Roots of crosscap slides and crosscap transpositions

    OpenAIRE

    Parlak, Anna; Stukow, Michał

    2016-01-01

    Let $N_{g}$ denote a closed nonorientable surface of genus $g$. For $g \\geq 2$ the mapping class group $\\mathcal{M}(N_{g})$ is generated by Dehn twists and one crosscap slide ($Y$-homeomorphism) or by Dehn twists and a crosscap transposition. Margalit and Schleimer observed that Dehn twists have nontrivial roots. We construct roots of crosscap slides and crosscap transpositions.

  14. On König's root finding algorithms

    DEFF Research Database (Denmark)

    Buff, Xavier; Henriksen, Christian

    2003-01-01

    In this paper, we first recall the definition of a family of root-finding algorithms known as König's algorithms. We establish some local and some global properties of those algorithms. We give a characterization of rational maps which arise as König's methods of polynomials with simple roots. We...

  15. A new approach to root formation

    OpenAIRE

    Vatanpour, Mehdi; Zarei, Mina; Javidi, Maryam; Shirazian, Shiva

    2008-01-01

    In endodontics, treatment of an open apex tooth with necrotic pulp is a problem. It seems that with promotion of remnants of Hertwig’s epithelial sheath or rest of malassez accompany with a good irrigation of root canal we can expect root formation. (Iranian Endodontic Journal 2008;3:42-43)

  16. Layers of root nouns in Germanic

    DEFF Research Database (Denmark)

    Hansen, Bjarne Simmelkjær Sandgaard

    2015-01-01

    The root-noun declension became productive in early Germanic, containing (I) inherited root nouns, (IIa) original substrate or loan words, and transitions from other declensions in (IIb) Proto-Germanic and (III) North Germanic. As ablaut was abolished, the inherited type would display ablaut grad...

  17. Salt stress signals shape the plant root

    NARCIS (Netherlands)

    C.S. Galvan-Ampudia; C. Testerink

    2011-01-01

    Plants use different strategies to deal with high soil salinity. One strategy is activation of pathways that allow the plant to export or compartmentalise salt. Relying on their phenotypic plasticity, plants can also adjust their root system architecture (RSA) and the direction of root growth to avo

  18. Method for Constructing Standardized Simulated Root Canals.

    Science.gov (United States)

    Schulz-Bongert, Udo; Weine, Franklin S.

    1990-01-01

    The construction of visual and manipulative aids, clear resin blocks with root-canal-like spaces, for simulation of root canals is explained. Time, materials, and techniques are discussed. The method allows for comparison of canals, creation of any configuration of canals, and easy presentation during instruction. (MSE)

  19. The Complexity of Rooted Phylogeny Problems

    CERN Document Server

    Bodirsky, Manuel

    2011-01-01

    Several computational problems in phylogenetic reconstruction can be formulated as restrictions of the following general problem: given a formula in conjunctive normal form where the literals are rooted triples, is there a rooted binary tree that satisfies the formula? If the formulas do not contain disjunctions, the problem becomes the famous rooted triple consistency problem, which can be solved in polynomial time by an algorithm of Aho, Sagiv, Szymanski, and Ullman. If the clauses in the formulas are restricted to disjunctions of negated triples, Ng, Steel, and Wormald showed that the problem remains NP-complete. We systematically study the computational complexity of the problem for all such restrictions of the clauses in the input formula. For certain restricted disjunctions of triples we present an algorithm that has sub-quadratic running time and is asymptotically as fast as the fastest known algorithm for the rooted triple consistency problem. We also show that any restriction of the general rooted ph...

  20. Formation and separation of root border cells.

    Science.gov (United States)

    Driouich, Azeddine; Durand, Caroline; Vicré-Gibouin, Maïté

    2007-01-01

    Plant roots release a large number of border cells into the rhizosphere, which are believed to play a key role in root development and health. The formation and loss of these cells from the root cap region is a developmentally regulated process that is also controlled by phytohormones and environmental factors. The separation of border cells involves the complete dissociation of individual cells from each other and from root tissue. This process requires the activity of cell wall-degrading enzymes that solubilize the cell wall connections between cells. We present and discuss the solubilization process with an emphasis on pectin-degrading enzymes as well as the recently discovered root border-like cells of Arabidopsis thaliana.

  1. Clinical management of infected root canal dentin.

    Science.gov (United States)

    Love, R M

    1996-08-01

    Several hundred different species of bacteria are present in the human intraoral environment. Bacterial penetration of root canal dentin occurs when bacteria invade the root canal system. These bacteria may constitute a reservoir from which root canal reinfection may occur during or after endodontic treatment. The learning objective of this article is to review endodontic microbiology, update readers on the role of bacteria in pulp and periapical disease, and discuss the principles of management of infected root canal dentin. Complete debridement, removal of microorganisms and affected dentin, and chemomechanical cleansing of the root canal are suggested as being the cornerstones of successful endodontic therapy, followed by intracanal medication to remove residual bacteria, when required.

  2. Effect of lead on root growth.

    Science.gov (United States)

    Fahr, Mouna; Laplaze, Laurent; Bendaou, Najib; Hocher, Valerie; Mzibri, Mohamed El; Bogusz, Didier; Smouni, Abdelaziz

    2013-01-01

    Lead (Pb) is one of the most widespread heavy metal contaminant in soils. It is highly toxic to living organisms. Pb has no biological function but can cause morphological, physiological, and biochemical dysfunctions in plants. Plants have developed a wide range of tolerance mechanisms that are activated in response to Pb exposure. Pb affects plants primarily through their root systems. Plant roots rapidly respond either (i) by the synthesis and deposition of callose, creating a barrier that stops Pb entering (ii) through the uptake of large amounts of Pb and its sequestration in the vacuole accompanied by changes in root growth and branching pattern or (iii) by its translocation to the aboveground parts of plant in the case of hyperaccumulators plants. Here we review the interactions of roots with the presence of Pb in the rhizosphere and the effect of Pb on the physiological and biochemical mechanisms of root development.

  3. Root Canal Treatment of a Maxillary Second Premolar with Two Palatal Root Canals: A Case Report.

    Science.gov (United States)

    Golmohammadi, Maryam; Jafarzadeh, Hamid

    2016-01-01

    Accurate diagnosis of the root canal morphology and anatomy is essential for thorough shaping and cleaning of the entire root canal system and consequent successful treatment. This report describes a case of maxillary second premolar with two roots and three root canals (two mesial and distal palatal canals). The case report underlines the importance of complete knowledge about root canal morphology and possible variations, coupled with clinical and radiographic examination in order to increase the ability of clinicians to treat difficult cases. PMID:27471538

  4. Aerenchyma Formed Under Phosphorus Deficiency Contributes to the Reduced Root Hydraulic Conductivity in Maize Roots

    Institute of Scientific and Technical Information of China (English)

    Mingshou Fan; Ruiqin Bai; Xuefeng Zhao; Jianhua Zhang

    2007-01-01

    Root hydraulic conductivity has been shown to decrease under phosphorus (P) deficiency. This study investigated how the formation of aerenchyma is related to this change. Root anatomy, as well as root hydraulic conductivity was studied in maize (Zea mays L.) roots under different phosphorus nutrition conditions. Plant roots under P stress showed enhanced degradation of cortical cells and the aerenchyma formation was associated with their reduced root hydraulic conductivity, supporting our hypothesis that air spaces that form in the cortex of phosphorusstressed roots impede the radial transport of water in a root cylinder. Further evidence came from the variation in aerenchyma formation due to genotypic differences. Five maize inbred lines with different porosity in their root cortex showed a significant negative correlation with their root hydraulic conductivity. Shoot relative water content was also found lower in P-deficient maize plants than that in P-sufficient ones when such treatment was prolonged enough, suggesting a limitation of water transport due to lowered root hydraulic conductivity of P-deficient piants.

  5. Getting to the roots of it: Genetic and hormonal control of root architecture

    Directory of Open Access Journals (Sweden)

    Janelle Kang Hui Jung

    2013-06-01

    Full Text Available Root system architecture (RSA--the spatial configuration of a root system--is an important developmental and agronomic trait, with implications for overall plant architecture, growth rate and yield, abiotic stress resistance, nutrient uptake, and developmental plasticity in response to environmental changes. Root architecture is modulated by intrinsic, hormone-mediated pathways, intersecting with pathways that perceive and respond to external, environmental signals. The recent development of several non-invasive 2D and 3D root imaging systems has enhanced our ability to accurately observe and quantify architectural traits on complex whole-root systems. Coupled with the powerful marker-based genotyping and sequencing platforms currently available, these root phenotyping technologies lend themselves to large-scale genome-wide association studies (GWAS, and can speed the identification and characterization of the genes and pathways involved in root system development. This capability provides the foundation for examining the contribution of root architectural traits to the performance of crop varieties in diverse environments. This review focuses on our current understanding of the genes and pathways involved in determining root system architecture in response to both intrinsic and extrinsic (environmental response pathways, and provides a brief overview of the latest root system phenotyping technologies and their potential impact on elucidating the genetic control of root development in plants.

  6. Resistance to compression of weakened roots subjected to different root reconstruction protocols

    Directory of Open Access Journals (Sweden)

    Lucas Villaça Zogheib

    2011-12-01

    Full Text Available OBJECTIVE: This study evaluated, in vitro, the fracture resistance of human non-vital teeth restored with different reconstruction protocols. MATERIAL AND METHODS: Forty human anterior roots of similar shape and dimensions were assigned to four groups (n=10, according to the root reconstruction protocol: Group I (control: non-weakened roots with glass fiber post; Group II: roots with composite resin by incremental technique and glass fiber post; Group III: roots with accessory glass fiber posts and glass fiber post; and Group IV: roots with anatomic glass fiber post technique. Following post cementation and core reconstruction, the roots were embedded in chemically activated acrylic resin and submitted to fracture resistance testing, with a compressive load at an angle of 45º in relation to the long axis of the root at a speed of 0.5 mm/min until fracture. All data were statistically analyzed with bilateral Dunnett's test (α=0.05. RESULTS: Group I presented higher mean values of fracture resistance when compared with the three experimental groups, which, in turn, presented similar resistance to fracture among each other. None of the techniques of root reconstruction with intraradicular posts improved root strength, and the incremental technique was suggested as being the most recommendable, since the type of fracture that occurred allowed the remaining dental structure to be repaired. CONCLUSION: The results of this in vitro study suggest that the healthy remaining radicular dentin is more important to increase fracture resistance than the root reconstruction protocol.

  7. Root cap influences root colonisation by Pseudomonas fluorescens SBW25 on maize.

    Science.gov (United States)

    Humphris, Sonia N; Bengough, A Glyn; Griffiths, Bryan S; Kilham, Ken; Rodger, Sheena; Stubbs, Vicky; Valentine, Tracy A; Young, Iain M

    2005-09-01

    We investigated the influence of root border cells on the colonisation of seedling Zea mays roots by Pseudomonas fluorescens SBW25 in sandy loam soil packed at two dry bulk densities. Numbers of colony forming units (CFU) were counted on sequential sections of root for intact and decapped inoculated roots grown in loose (1.0 mg m(-3)) and compacted (1.3 mg m(-3)) soil. After two days of root growth, the numbers of P. fluorescens (CFU cm(-1)) were highest on the section of root just below the seed with progressively fewer bacteria near the tip, irrespective of density. The decapped roots had significantly more colonies of P. fluorescens at the tip compared with the intact roots: approximately 100-fold more in the loose and 30-fold more in the compact soil. In addition, confocal images of the root tips grown in agar showed that P. fluorescens could only be detected on the tips of the decapped roots. These results indicated that border cells, and their associated mucilage, prevented complete colonization of the root tip by the biocontrol agent P. fluorescens, possibly by acting as a disposable surface or sheath around the cap.

  8. Accessory roots and root canals in human anterior teeth: a review and clinical considerations.

    Science.gov (United States)

    Ahmed, H M A; Hashem, A A

    2016-08-01

    Anterior teeth may have aberrant anatomical variations in the number of roots and root canals. A review of the literature was conducted using appropriate key words in major endodontic journals to identify the available reported cases as well as experimental and clinical investigations on accessory roots and root canals in anterior teeth. After retrieving the full text of related articles, cross-citations were identified, and the pooled data were then discussed. Results revealed a higher prevalence in accessory root/root canal variations in mandibular anterior teeth than in maxillary counterparts. However, maxillary incisor teeth revealed the highest tendency for accessory root/root canal aberrations caused by anomalies such as dens invaginatus and palato-gingival groove. Primary anterior teeth may also exhibit external and internal anatomical variations in the root, especially maxillary canines. Therefore, dental practitioners should thoroughly assess all teeth scheduled for root canal treatment to prevent the undesirable consequences caused by inadequate debridement of accessory configurations of the root canal system. PMID:26174943

  9. RootGraph: a graphic optimization tool for automated image analysis of plant roots.

    Science.gov (United States)

    Cai, Jinhai; Zeng, Zhanghui; Connor, Jason N; Huang, Chun Yuan; Melino, Vanessa; Kumar, Pankaj; Miklavcic, Stanley J

    2015-11-01

    This paper outlines a numerical scheme for accurate, detailed, and high-throughput image analysis of plant roots. In contrast to existing root image analysis tools that focus on root system-average traits, a novel, fully automated and robust approach for the detailed characterization of root traits, based on a graph optimization process is presented. The scheme, firstly, distinguishes primary roots from lateral roots and, secondly, quantifies a broad spectrum of root traits for each identified primary and lateral root. Thirdly, it associates lateral roots and their properties with the specific primary root from which the laterals emerge. The performance of this approach was evaluated through comparisons with other automated and semi-automated software solutions as well as against results based on manual measurements. The comparisons and subsequent application of the algorithm to an array of experimental data demonstrate that this method outperforms existing methods in terms of accuracy, robustness, and the ability to process root images under high-throughput conditions.

  10. PHIV-RootCell: a supervised image analysis tool for rice root anatomical parameter quantification

    Directory of Open Access Journals (Sweden)

    Marc eLartaud

    2015-01-01

    Full Text Available We developed the PHIV-RootCell software to quantify anatomical traits of rice roots transverse section images. Combined with an efficient root sample processing method for image acquisition, this program permits supervised measurements of areas (those of whole root section, stele, cortex and central metaxylem vessels, number of cell layers and number of cells per cell layer. The PHIV-RootCell toolset runs under ImageJ, an independent operating system that has a license-free status. To demonstrate the usefulness of PHIV-RootCell, we conducted a genetic diversity study and an analysis of salt-stress responses of root anatomical parameters in rice (Oryza sativa L.. Using 16 cultivars, we showed that we could discriminate between some of the varieties even at the 6 day-old stage, and that tropical japonica varieties had larger root sections due to an increase in cell number. We observed, as described previously, that root sections become enlarged under salt stress. However, our results show an increase in cell number in ground tissues (endodermis and cortex but a decrease in external (peripheral tissues (sclerenchyma, exodermis and epidermis. Thus, the PHIV-RootCell program is a user-friendly tool that will be helpful for future genetic and physiological studies that investigate root anatomical trait variations.

  11. Root phenology at Harvard Forest and beyond

    Science.gov (United States)

    Abramoff, R. Z.; Finzi, A.

    2013-12-01

    Roots are hidden from view and heterogeneously distributed making them difficult to study in situ. As a result, the causes and timing of root production are not well understood. Researchers have long assumed that above and belowground phenology is synchronous; for example, most parameterizations of belowground carbon allocation in terrestrial biosphere models are based on allometry and represent a fixed fraction of net C uptake. However, using results from metaanalysis as well as empirical data from oak and hemlock stands at Harvard Forest, we show that synchronous root and shoot growth is the exception rather than the rule. We collected root and shoot phenology measurements from studies across four biomes (boreal, temperate, Mediterranean, and subtropical). General patterns of root phenology varied widely with 1-5 production peaks in a growing season. Surprisingly, in 9 out of the 15 studies, the first root production peak was not the largest peak. In the majority of cases maximum shoot production occurred before root production (Offset>0 in 32 out of 47 plant sample means). The number of days offset between maximum root and shoot growth was negatively correlated with median annual temperature and therefore differs significantly across biomes (ANOVA, F3,43=9.47, pinfluenced the relative timing of root and shoot growth. Woody plants had a larger range of days between root and shoot growth peaks as well as a greater number of growth peaks. To explore the range of phenological relationships within woody plants in the temperate biome, we focused on above and belowground phenology in two common northeastern tree species, Quercus rubra and Tsuga canadensis. Greenness index, rate of stem growth, root production and nonstructural carbohydrate content were measured beginning in April 2012 through August 2013 at the Harvard Forest in Petersham, MA, USA. Greenness and stem growth were highest in late May and early June with one clear maximum growth period. In contrast, root

  12. Spiralizations and tropisms in Arabidopsis roots.

    Science.gov (United States)

    Migliaccio, F; Piconese, S

    2001-12-01

    When Arabidopsis seedlings are grown on a hard-agar plate, their primary roots show characteristic spiralling movements, apparent as waves, coils and torsions, together with a slanting toward the right-hand side. All these movements are believed to be the result of three different processes acting on the roots: circumnutation, positive gravitropism and negative thigmotropism. The basic movement of the roots is described as that of a growing right-handed helix, which, because of the root tip hitting the agar plate, is continuously switched from the right-hand to the left-hand of the growth direction, and vice versa. This movement also produces a slanting root-growth direction toward the right-hand because of the incomplete waves made by the right-handed root to the left-hand. By contrast, the torsions seen in the coils and waves are interpreted as artefacts that form as an adaptation of the three-dimensional root helix to the flat two-dimensional agar surface.

  13. A thermodynamic formulation of root water uptake

    Science.gov (United States)

    Hildebrandt, Anke; Kleidon, Axel; Bechmann, Marcel

    2016-08-01

    By extracting bound water from the soil and lifting it to the canopy, root systems of vegetation perform work. Here we describe how root water uptake can be evaluated thermodynamically and demonstrate that this evaluation provides additional insights into the factors that impede root water uptake. We derive an expression that relates the energy export at the base of the root system to a sum of terms that reflect all fluxes and storage changes along the flow path in thermodynamic terms. We illustrate this thermodynamic formulation using an idealized setup of scenarios with a simple model. In these scenarios, we demonstrate why heterogeneity in soil water distribution and rooting properties affect the impediment of water flow even though the mean soil water content and rooting properties are the same across the scenarios. The effects of heterogeneity can clearly be identified in the thermodynamics of the system in terms of differences in dissipative losses and hydraulic energy, resulting in an earlier start of water limitation in the drying cycle. We conclude that this thermodynamic evaluation of root water uptake conveniently provides insights into the impediments of different processes along the entire flow path, which goes beyond resistances and also accounts for the role of heterogeneity in soil water distribution.

  14. Root distribution of rootstocks for 'Tahiti' lime

    Directory of Open Access Journals (Sweden)

    Neves Carmen Silvia Vieira Janeiro

    2004-01-01

    Full Text Available Field studies on citrus roots are important for genetic selection of cultivars and for management practices such as localized irrigation and fertilization. To characterize root systems of six rootstocks, taking into consideration chemical and physical characteristics of a clayey Typic Hapludox of the Northern State of Paraná, this study was performed having as scion the 'IAC-5 Tahiti' lime [Citrus latifolia (Yu. Tanaka]. The rootstocks 'Rangpur' lime (C. limonia Osbeck, 'Africa Rough' lemon (C. jambhiri Lush., 'Sunki' mandarin [C. sunki (Hayata hort. ex Tan.], Poncirus trifoliata (L. Raf., 'C13' citrange [C. sinensis (L. Osb. x P. trifoliata (L. Raf] and 'Catânia 2' Volkamer lemon (C. volkameriana Ten. & Pasq. were used applying the trench profile method and the SIARCS® 3.0 software to determine root distribution. 'C-13' citrange had the largest root system. 'Volkamer' lemon and 'Africa Rough' lemon presented the smallest amount of roots. The effective depth for 80 % of roots was 31-53 cm in rows and 67-68 cm in inter-rows. The effective distance of 80 % of roots measured from the tree trunk exceeded the tree canopy for P. trifoliata, 'Sunki' mandarin, and 'Volkamer' and 'Africa Rough' lemons.

  15. How to bond to root canal dentin

    Science.gov (United States)

    Nica, Luminita; Todea, Carmen; Furtos, Gabriel; Baldea, Bogdan

    2014-01-01

    Bonding to root canal dentin may be difficult due to various factors: the structural characteristic of the root canal dentin, which is different from that of the coronal dentin; the presence of the organic tissue of the dental pulp inside the root canal, which has to be removed during the cleaning-shaping of the root canal system; the smear-layer resulted after mechanical instrumentation, which may interfere with the adhesion of the filling materials; the type of the irrigants used in the cleaning protocol; the type of the sealer and core material used in the obturation of the endodontic space; the type of the materials used for the restoration of the endodontically treated teeth. The influence of the cleaning protocol, of the root canal filling material, of the type of the adhesive system used in the restoration of the treated teeth and of the region of the root canal, on the adhesion of several filling and restorative materials to root canal dentin was evaluated in the push-out bond strength test on 1-mm thick slices of endodontically treated human teeth. The results showed that all these factors have a statistically significant influence on the push-out bond strength. Formation of resin tags between radicular dentin and the investigated materials was observed in some of the samples at SEM analysis.

  16. Tractography of lumbar nerve roots: initial results

    Energy Technology Data Exchange (ETDEWEB)

    Balbi, Vincent; Budzik, Jean-Francois; Thuc, Vianney le; Cotten, Anne [Hopital Roger Salengro, Service de Radiologie et d' Imagerie musculo-squelettique, Lille Cedex (France); Duhamel, Alain [Universite de Lille 2, UDSL, Lille (France); Bera-Louville, Anne [Service de Rhumatologie, Hopital Roger Salengro, Lille (France)

    2011-06-15

    The aims of this preliminary study were to demonstrate the feasibility of in vivo diffusion tensor imaging (DTI) and fibre tracking (FT) of the lumbar nerve roots, and to assess potential differences in the DTI parameters of the lumbar nerves between healthy volunteers and patients suffering from disc herniation. Nineteen patients with unilateral sciatica related to posterolateral or foraminal disc herniation and 19 healthy volunteers were enrolled in this study. DTI with tractography of the L5 or S1 nerves was performed. Mean fractional anisotropy (FA) and mean diffusivity (MD) values were calculated from tractography images. FA and MD values could be obtained from DTI-FT images in all controls and patients. The mean FA value of the compressed lumbar nerve roots was significantly lower than the FA of the contralateral nerve roots (p=0.0001) and of the nerve roots of volunteers (p=0.0001). MD was significantly higher in compressed nerve roots than in the contralateral nerve root (p=0.0002) and in the nerve roots of volunteers (p=0.04). DTI with tractography of the lumbar nerves is possible. Significant changes in diffusion parameters were found in the compressed lumbar nerves. (orig.)

  17. A thermodynamic formulation of root water uptake

    Science.gov (United States)

    Hildebrandt, A.; Kleidon, A.; Bechmann, M.

    2015-12-01

    By extracting bound water from the soil and lifting it to the canopy, root systems of vegetation perform work. Here we describe how the energetics involved in root water uptake can be quantified. The illustration is done using a simple, four-box model of the soil-root system to represent heterogeneity and a parameterization in which root water uptake is driven by the xylem potential of the plant with a fixed flux boundary condition. We use this approach to evaluate the effects of soil moisture heterogeneity and root system properties on the dissipative losses and export of energy involved in root water uptake. For this, we derive an expression that relates the energy export at the root collar to a sum of terms that reflect all fluxes and storage changes along the flow path in thermodynamic terms. We conclude that such a thermodynamic evaluation of root water uptake conveniently provides insights into the impediments of different processes along the entire flow path and explicitly accounting not only for the resistances along the flow path and those imposed by soil drying but especially the role of heterogenous soil water distribution. The results show that least energy needs to be exported and dissipative losses are minimized by a root system if it extracts water uniformly from the soil. This has implications for plant water relations in forests where canopies generate heterogenous input patterns. Our diagnostic in the energy domain should be useful in future model applications for quantifying how plants can evolve towards greater efficiency in their structure and function, particularly in heterogenous soil environments. Generally, this approach may help to better describe heterogeneous processes in the soil in a simple, yet physically-based way.

  18. Effects of acid deposition on tree roots

    Energy Technology Data Exchange (ETDEWEB)

    Persson, H. [Swedish Univ. of Agricultural Sciences (Sweden). Dept. of Ecology and Environmental Research

    1995-12-31

    Large forest regions in SW Sweden have been exposed to high levels of acid deposition for many decades, causing soil acidification in forest soils. Historically, SO{sub 2} has been the major acidification agent, but lately nitrogen compounds increasingly have become important. The amount and chemical form of nitrogen strongly affects the pH in the rhizosphere and rhizoplane. Many forest stands show a positive growth response to increased nitrogen input, even in heavily N-loaded areas. Nitrogen fertilization experiments suggest that part of the increased forest production is caused by a translocation of biomass production from below-ground to above-ground parts. At the same time fine-root growth dynamics are strongly affected by the high N supply. Deficiencies of various nutrients (Mg,Ca,K,Mn and Zn) obtained from needle analyses have been reported from different Picea abies stands. In areas with more extensive acidification and nutrient leaching, a decline in tree vitality has been observed. Although deficiency symptoms in forest trees may be reflected in nitrogen/cation ratios in fine roots, few attempts have been made to explain forest damage symptoms from fine-root chemistry. Root damage is often described as a decline in the amount of living fine roots, an increase in the amount of dead versus live fine roots (a lower live/dead ratio) and an increasing amount of dead medium and coarse roots. The primary objectives of the present presentation were to analyse available data on the effects of high nitrogen and sulphur deposition on mineral nutrient balance in tree fine roots and to evaluate the risk of Al interference with cation uptake by roots

  19. Root type matters: measurements of water uptake by seminal, crown and lateral roots of maize

    Science.gov (United States)

    Ahmed, Mutez Ali; Zarebanadkouki, Mohsen; Kaestner, Anders; Carminati, Andrea

    2016-04-01

    Roots play a key role in water acquisition and are a significant component of plant adaptation to different environmental conditions. Although maize (Zea mays L.) is one of the most important crops worldwide, there is limited information on the function of different root segments and types in extracting water from soils. Aim of this study was to investigate the location of root water uptake in mature maize. We used neutron radiography to image the spatial distribution of maize roots and trace the transport of injected deuterated water (D2O) in soil and roots. Maize plants were grown in aluminum containers filled with a sandy soil that was kept homogeneously wet throughout the experiment. When the plants were five weeks-old, we injected D2O into selected soil regions. The transport of D2O was simulated using a diffusion-convection numerical model. By fitting the observed D2O transport we quantified the diffusion coefficient and the water uptake of the different root segments. The model was initially developed and tested with two weeks-old maize (Ahmed et. al. 2015), for which we found that water was mainly taken up by lateral roots and the water uptake of the seminal roots was negligible. Here, we used this method to measure root water uptake in a mature maize root system. The root architecture of five weeks-old maize consisted of primary and seminal roots with long laterals and crown (nodal) roots that emerged from the above ground part of the plant two weeks after planting. The crown roots were thicker than the seminal roots and had fewer and shorter laterals. Surprisingly, we found that the water was mainly taken up by the crown roots and their laterals, while the lateral roots of seminal roots, which were the main location of water uptake of younger plants, stopped to take up water. Interestingly, we also found that in contrast to the seminal roots, the crown roots were able to take up water also from their distal segments. We conclude that for the two weeks

  20. Pullout tests of root analogs and natural root bundles in soil: Experiments and modeling

    Science.gov (United States)

    Schwarz, M.; Cohen, D.; Or, D.

    2011-06-01

    Root-soil mechanical interactions are key to soil stability on steep hillslopes. Motivated by new advances and applications of the Root Bundle Model (RBM), we conducted a series of experiments in the laboratory and in the field to study the mechanical response of pulled roots. We systematically quantified the influence of different factors such as root geometry and configuration, soil type, and soil water content considering individual roots and root bundles. We developed a novel pullout apparatus for strain-controlled field and laboratory tests of up to 13 parallel roots measured individually and as a bundle. Results highlight the importance of root tortuosity and root branching points for prediction of individual root pullout behavior. Results also confirm the critical role of root diameter distribution for realistic prediction of global pullout behavior of a root bundle. Friction between root and soil matrix varied with soil type and water content and affected the force-displacement behavior. Friction in sand varied from 1 to 17 kPa, with low values obtained in wet sand at a confining pressure of 2 kPa and high values obtained in dry sand with 4.5 kPa confining pressure. In a silty soil matrix, friction ranged between 3 kPa under wet and low confining pressure (2 kPa) and 6 kPa in dry and higher confining pressure (4.5 kPa). Displacement at maximum pullout force increased with increasing root diameter and with tortuosity. Laboratory experiments were used to calibrate the RBM that was later validated using six field measurements with natural root bundles of Norway spruce (Picea abies L.). These tests demonstrate the progressive nature of root bundle failure under strain-controlled pullout force and provide new insights regarding force-displacement behavior of root reinforcement, highlighting the importance of considering displacement in slope stability models. Results show that the magnitude of maximum root pullout forces (1-5 kPa) are important for slope

  1. THttpServer class in ROOT

    Science.gov (United States)

    Adamczewski-Musch, Joern; Linev, Sergey

    2015-12-01

    The new THttpServer class in ROOT implements HTTP server for arbitrary ROOT applications. It is based on Civetweb embeddable HTTP server and provides direct access to all objects registered for the server. Objects data could be provided in different formats: binary, XML, GIF/PNG, and JSON. A generic user interface for THttpServer has been implemented with HTML/JavaScript based on JavaScript ROOT development. With any modern web browser one could list, display, and monitor objects available on the server. THttpServer is used in Go4 framework to provide HTTP interface to the online analysis.

  2. ANTIARTHRITIC ACTIVITY OF DESMODIUM GANGETICUM ROOT

    Directory of Open Access Journals (Sweden)

    Vedpal

    2013-09-01

    Full Text Available The present study is aimed to evaluate the in-vitro anti-arthritic activity of aqueous extract of Desmodium gangeticum root using inhibition of protein denaturation model and human red blood cell Membrane stabilization model. Diclofenac sodium was used as a standard drug. Results revealed that the aqueous extract of Desmodium gangeticum root at different concentrations possessed significant anti-arthritic activity as compared to standard drug used as Diclofenac sodium. The results obtained in the present investigation Indicate that aqueous extract of Desmodium gangeticum root showed anti-arthritic activity.

  3. Root activity pattern of eucalyptus camaldulensis dehnhardt

    International Nuclear Information System (INIS)

    The root activity pattern of a seven-year-old E. camaldulensis was studied by 32P capsule placement technique. The study revealed that nearly two-third of the roots of E. camaldulensis are confined to the top 60 cm of the soil layer. Laterally, one-third of the roots are confined within the 50 cm radial distance from the trunk of the tree and the remaining two-thirds are spread at a radial distance of 75 to 100 cm. (author)

  4. Complex root networks of Chinese characters

    Science.gov (United States)

    Lee, Po-Han; Chen, Jia-Ling; Wang, Po-Cheng; Chi, Ting-Ting; Xiao, Zhi-Ren; Jhang, Zih-Jian; Yeh, Yeong-Nan; Chen, Yih-Yuh; Hu, Chin-Kun

    There are several sets of Chinese characters still available today, including Oracle Bone Inscriptions (OBI) in Shang Dynasty, Chu characters (CC) used in Chu of Warring State Period, Small Seal Script in dictionary Shuowen Jiezi (SJ) in Eastern Han Dynasty, and Kangxi Dictionary (KD) in Qing Dynasty. Such as Chinese characters were all constructed via combinations of meaningful patterns, called roots. Our studies for the complex networks of all roots indicate that the roots of the characters in OBI, CC, SJ and KD have characteristics of small world networks and scale-free networks.

  5. A "square-root rule" for reinsurance

    Directory of Open Access Journals (Sweden)

    Michael R. Powers

    2006-12-01

    Full Text Available In previous work, the authors derived a mathematical expression for the optimal (or "saturation" number of reinsurers for a given number of primary insurers (see Powers and Shubik, 2001. In the current article, we show analytically that, for large numbers of primary insurers, this mathematical expression provides a "square-root rule"; i.e., the optimal number of reinsurers in a market is given asymptotically by the square root of the total number of primary insurers. We note further that an analogous "fourth-root rule" applies to markets for retrocession (the reinsurance of reinsurance.

  6. On rigidity of abstract root systems of Coxeter systems

    OpenAIRE

    Dyer, Matthew

    2010-01-01

    We introduce and study a combinatorially defined notion of root basis of a (real) root system of a possibly infinite Coxeter group. Known results on conjugacy up to sign of root bases of certain irreducible finite rank real root systems are extended to abstract root bases, to a larger class of real root systems, and, with a short list of (genuine) exceptions, to infinite rank irreducible Coxeter systems.

  7. Phosphate Availability Alters Lateral Root Anatomy and Root Architecture of Fraxinus mandshurica Rupr. Seedlings

    Institute of Scientific and Technical Information of China (English)

    Chu WU; Xing WEI; Hai-Long SUN; Zheng-Quan WANG

    2005-01-01

    Plants have evolved some mechanisms to maximize the efficiency of phosphorus acquisition.Changes in root architecture are one such mechanism. When Fraxinus mandshurica Rupr. seedlings were grown under conditions of low phosphorus availability, the length of cells in the meristem zone of the lateral roots was longer, but the length of cells in the elongation and mature zones of the lateral roots was shorter,compared with seedlings grown under conditions of high phosphorus availability. The elongation rates of primary roots increased as phosphorus availability increased, but the elongation rates of the branched zones of the primary roots decreased. The number of lateral root primordia and the length of the lateral roots decreased as phosphorus availability increased. The topological index (altitude slope) decreased as phosphorus availability increased, suggesting that root architecture tended to be herringbone-like when seedlings were grown under conditions of low phosphate availability. Herringbone-like root systems exploit nutrients more efficiently, but they have higher construction costs than root systems with a branching pattern.

  8. The Root Cap Determines Ethylene-Dependent Growth and Development in Maize Roots

    Institute of Scientific and Technical Information of China (English)

    Achim Hahn; Roman Zimmermann; Dierk Wanke; Klaus Harter; Hans G.Edelmann

    2008-01-01

    Besides providing protection against mechanical damage to the root tip,the root cap is involved in the perception and processing of diverse external and internal stimuli resulting in altered growth and development.The transduction of these stimuli includes hormonal signaling pathways such as those of auxin,ethylene and cytokinin.Here,we show that the root cap is essential for the ethylene-induced regulation of elongation growth and root hair formation in maize.Exogenously applied ethylene is no longer able to inhibit elongation growth when the root cap has been surgically removed prior to hormone treatment.Reconstitution of the cap positively correlates with the developing capacity of the roots to respond to ethylene again.In contrast,the removal of the root cap does not per se affect growth inhibition controlled by auxin and cytokinin.Furthermore,our semi-quantitative RT-PCR results support earlier findings that the maize root cap is a site of high gene expression activity with respect to sensing and responding to hormones such as ethylene.From these data,we propose a novel function of the root cap which is the establishment of competence to respond to ethylene in the distal zones of the root.

  9. Plant roots use a patterning mechanism to position lateral root branches toward available water.

    Science.gov (United States)

    Bao, Yun; Aggarwal, Pooja; Robbins, Neil E; Sturrock, Craig J; Thompson, Mark C; Tan, Han Qi; Tham, Cliff; Duan, Lina; Rodriguez, Pedro L; Vernoux, Teva; Mooney, Sacha J; Bennett, Malcolm J; Dinneny, José R

    2014-06-24

    The architecture of the branched root system of plants is a major determinant of vigor. Water availability is known to impact root physiology and growth; however, the spatial scale at which this stimulus influences root architecture is poorly understood. Here we reveal that differences in the availability of water across the circumferential axis of the root create spatial cues that determine the position of lateral root branches. We show that roots of several plant species can distinguish between a wet surface and air environments and that this also impacts the patterning of root hairs, anthocyanins, and aerenchyma in a phenomenon we describe as hydropatterning. This environmental response is distinct from a touch response and requires available water to induce lateral roots along a contacted surface. X-ray microscale computed tomography and 3D reconstruction of soil-grown root systems demonstrate that such responses also occur under physiologically relevant conditions. Using early-stage lateral root markers, we show that hydropatterning acts before the initiation stage and likely determines the circumferential position at which lateral root founder cells are specified. Hydropatterning is independent of endogenous abscisic acid signaling, distinguishing it from a classic water-stress response. Higher water availability induces the biosynthesis and transport of the lateral root-inductive signal auxin through local regulation of tryptophan aminotransferase of Arabidopsis 1 and PIN-formed 3, both of which are necessary for normal hydropatterning. Our work suggests that water availability is sensed and interpreted at the suborgan level and locally patterns a wide variety of developmental processes in the root.

  10. Rooting depths of plants relative to biological and environmental factors

    Energy Technology Data Exchange (ETDEWEB)

    Foxx, T S; Tierney, G D; Williams, J M

    1984-11-01

    In 1981 to 1982 an extensive bibliographic study was completed to document rooting depths of native plants in the United States. The data base presently contains 1034 citations with approximately 12,000 data elements. In this paper the data were analyzed for rooting depths as related to life form, soil type, geographical region, root type, family, root depth to shoot height ratios, and root depth to root lateral ratios. Average rooting depth and rooting frequencies were determined and related to present low-level waste site maintenance.

  11. Understanding plant root system influences on soil strength and stability

    Science.gov (United States)

    Bengough, A. Glyn; Brown, Jennifer L.; Loades, Kenneth W.; Knappett, Jonathan A.; Meijer, Gertjan; Nicoll, Bruce

    2016-04-01

    Keywords: root growth, soil reinforcement, tensile strength Plant roots modify and reinforce the soil matrix, stabilising it against erosion and shallow landslides. Roots mechanically bind the soil particles together and modify the soil hydrology via water uptake, creation of biopores, and modification of the soil water-release characteristic. Key to understanding the mechanical reinforcement of soil by roots is the relation between root strength and root diameter measured for roots in any given soil horizon. Thin roots have frequently been measured to have a greater tensile strength than thick roots, but their strength is also often much more variable. We consider the factors influencing this strength-diameter relationship, considering relations between root tensile strength and root dry density, root water content, root age, and root turnover in several woody and non-woody species. The role of possible experimental artefacts and measurement techniques will be considered. Tensile strength increased generally with root age and decreased with thermal time after excision as a result of root decomposition. Single factors alone do not appear to explain the strength-diameter relationship, and both strength/stiffness and dry density may vary between different layers of tissue within a single root. Results will be discussed to consider how we can achieve a more comprehensive understanding of the variation in root biomechanical properties, and its consequences for soil reinforcement. Acknowledgements: The James Hutton Institute receives funding from the Scottish Government. AGB and JAK acknowledge part funding from EPSRC (EP/M020355/1).

  12. Rooting depths of plants relative to biological and environmental factors

    International Nuclear Information System (INIS)

    In 1981 to 1982 an extensive bibliographic study was completed to document rooting depths of native plants in the United States. The data base presently contains 1034 citations with approximately 12,000 data elements. In this paper the data were analyzed for rooting depths as related to life form, soil type, geographical region, root type, family, root depth to shoot height ratios, and root depth to root lateral ratios. Average rooting depth and rooting frequencies were determined and related to present low-level waste site maintenance

  13. Naine objektistab meest / Fideelia-Signe Roots

    Index Scriptorium Estoniae

    Roots, Fideelia-Signe, 1976-

    2009-01-01

    Fideelia-Signe Roots Eesti Kunstiakadeemias 2009. a. kevadsemestril enda poolt läbi viidud valikainekursusest "Kunstiteose anatoomiast mehe anatoomiani", mis lõppes näitusega "Tõuseb / ei tõuse" Eesti Tervishoiumuuseumis, avatud 31. maini

  14. An Improved Nonparametric Unit-Root Test

    OpenAIRE

    Jiti Gao; Maxwell King

    2012-01-01

    This paper proposes a simple and improved nonparametric unit-root test. An asymptotic distribution of the proposed test is established. Finite sample comparisons with an existing nonparametric test are discussed. Some issues about possible extensions are outlined.

  15. Elements with Square Roots in Finite Groups

    Institute of Scientific and Technical Information of China (English)

    M.S. Lucido; M.R. Pournaki

    2005-01-01

    In this paper, we study the probability that a randomly chosen element in a finite group has a square root, in particular the simple groups of Lie type of rank 1, the sporadic finite simple groups and the alternating groups.

  16. BGP reflection functors in root categories

    Institute of Scientific and Technical Information of China (English)

    XIAO; Jie; ZHANG; Guanglian; ZHU; Bin

    2005-01-01

    We define the BGP-reflection functors in the derived categories and the root categories. By Ringel's Hall algebra approach, the BGP-reflection functor is applicable to obtain the classical Weyl group action on the Lie algebra.

  17. DMA thermal analysis of yacon tuberous roots

    Science.gov (United States)

    Blahovec, J.; Lahodová, M.; Kindl, M.; Fernández, E. C.

    2013-12-01

    Specimens prepared from yacon roots in first two weeks after harvest were tested by dynamic mechanical analysis thermal analysis at temperatures between 30 and 90°C. No differences between different parts of roots were proved. There were indicated some differences in the test parameters that were caused by short time storage of the roots. One source of the differences was loss of water during the roots storage. The measured modulus increased during short time storage. Detailed study of changes of the modulus during the specimen dynamic mechanical analysis test provided information about different development of the storage and loss moduli during the specimen heating. The observed results can be caused by changes in cellular membranes observed earlier during vegetable heating, and by composition changes due to less stable components of yacon like inulin.

  18. Root Resorption in Orthodontics - Genetic Susceptibility?

    OpenAIRE

    Ponces, MJ; Paula Vaz; Fred Pinheiro; Inês Côrte-Real; Purificação Tavares

    2011-01-01

    OBJECTIVES: External root resorption (ERR) is a condition that can be observed in association with orthodontic treatment. The etiology of root resorption is complex, related with several factors. Some inflammatory mediators, controlled by specific genes, have been associated with bone resorption and in the recruitment of osteoclasts during orthodontic movement (Lee et al., 2007; Abass et al., 2008; Bastos et al., 2009). Particularly the association between polymorphisms in the IL-1B gene and ...

  19. COMMODITY PRICES AND UNIT ROOT TESTS

    OpenAIRE

    Wang, Dabin; Tomek, William G.

    2004-01-01

    Endogenous variables in structural models of agricultural commodity markets are typically treated as stationary. Yet, tests for unit roots have rather frequently implied that commodity prices are not stationary. This seeming inconsistency is investigated by focusing on alternative specifications of unit root tests. We apply various specifications to Illinois farm prices of corn, soybeans, barrows and gilts, and milk for the 1960 through 2002 time span. The preponderance of the evidence sugges...

  20. Pain associated with root canal treatment

    OpenAIRE

    Segura-Egea, Juan José; Cisneros Cabello, Rafael; Llamas Carreras, José María; Velasco Ortega, Eugenio

    2009-01-01

    Our purpose was to determine the pain experienced by patients during root canal treatment and to correlate with age and gender, pulpal diagnosis, previous periapical status, dental characteristics and length of treatment. One hundred and seventy-six patients (68 men and 108 women), with ages ranged from 6 to 83 years, were randomly recruited. Patients completed a 10-cm visual analogue scale (VAS) that ranked the level of pain experienced during root canal treatment. The mean pain level during...

  1. ANTIARTHRITIC ACTIVITY OF DESMODIUM GANGETICUM ROOT

    OpenAIRE

    Vedpal; Santosh Kumar Gupta; Gupta, A K; Dhirendra Pakash; Amit Gupta

    2013-01-01

    The present study is aimed to evaluate the in-vitro anti-arthritic activity of aqueous extract of Desmodium gangeticum root using inhibition of protein denaturation model and human red blood cell Membrane stabilization model. Diclofenac sodium was used as a standard drug. Results revealed that the aqueous extract of Desmodium gangeticum root at different concentrations possessed significant anti-arthritic activity as compared to standard drug used as Diclofenac sodium. The results obtained in...

  2. Nitrogen uptake and assimilation by corn roots

    International Nuclear Information System (INIS)

    The site of nitrogen uptake in the apical root zone of corn was experimentally investigated. Two experiments were performed. The one is to see the assimilation of nitrate and ammonium and the effects of low temperature on it. The 4-day-old roots were treated with 15N-labelled inorganic nitrogen of 20 ppm N in 5 x 10-4M CaSO4 solution at 30 deg. C and 0 deg. C. The other is to see the nitrogen uptake at apical root zone and the utilization of newly absorbed nitrogen at the root top. The 4-day-old roots were transferred into 5 x 10-4M CaSO4 solution containing 15N-labelled ammonium nitrate of 40 ppm N. As a result, the effect of low temperature on the nitrogen uptake appeared to be more drastic in the case of nitrate than ammonium. The 15N content of amino acids indicates that ammonium is assimilated into amino acids even at 0 deg. C, but nitrate is not. The ammonium nitrogen seemed to be absorbed at both cell dividing and elongating zones. On the other hand, nitrate nitrogen seemed to be strongly absorbed at cell elongating zone. The nitrogen in the apical part may be supplied not only by direct absorption but also by translocation from the basal part. The clear difference was found in the utilization of nitrate and ammonium nitrogen at the root top when the root was elongating. This may be due to the difference of assimilation products of inorganic nitrogen. Newly absorbed ammonium nitrogen is more utilizable for the growth of root top than nitrate nitrogen. (Iwakiri, K.)

  3. Immunology of root resorption: A literature review

    Directory of Open Access Journals (Sweden)

    Silva Luciano

    2008-01-01

    Full Text Available Root resorption seems to be related to a complex combination of mechanical factors and biological activity, which comprehends the role of immunologic structures including specialized cells. The aim of this research was to explain the development of the process - from mineralization to the destruction of hard tissues - and the possible relationship between root resorption and immunology, along with discussing current concepts described in the literature.

  4. Heterobasidion root rot in Norway spruce

    OpenAIRE

    Thor, Magnus

    2005-01-01

    In spite of its biological and economic impact on Swedish forestry, root rot caused by Heterobasidion annosum (Fr.) Bref. sensu lato has received no or little attention in forest planning. This thesis summarizes and discusses two experiments involving prophylactic treatment of stumps, and three investigations on the modelling and simulation of root rot in coniferous stands with special emphasis on Norway spruce (Picea abies [L.] Karst.). In 14 previously unthinned stands of Norway spruce, the...

  5. Development of TRatioPlot in ROOT

    CERN Document Server

    Gessinger-Befurt, Paul

    2016-01-01

    The ROOT data analysis and visualization framework is a software package which is widely used in physics, especially in high energy physics. A common visualization which has so far been lacking a direct implementation is the ratio plot, as well as a few similar types of plots. The scope and goal of the summer student project at CERN was to implement a class in ROOT itself, that can take care of the most common types of calculations, and produces high quality visuals.

  6. Two root canals in maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Fábio de Almeida Gomes

    2011-07-01

    Full Text Available Introduction and objective: The success of endodontic treatment requires the knowledge of tooth morphology and its variations. Case report: This clinical article reports an unusual root canal configuration that was detected in a maxillary central incisor with two root canals, demonstrated by radiographic and computerized tomography exams. Conclusion: Knowledge of endodontic anatomy as well as the obtainment of both preoperative radiographs and tomography is important to detect abnormal tooth morphology.

  7. Quadratic Interval Refinement for Real Roots

    CERN Document Server

    Abbott, John

    2012-01-01

    We present a new algorithm for refining a real interval containing a single real root: the new method combines characteristics of the classical Bisection algorithm and Newton's Iteration. Our method exhibits quadratic convergence when refining isolating intervals of simple roots of polynomials (and other well-behaved functions). We assume the use of arbitrary precision rational arithmetic. Unlike Newton's Iteration our method does not need to evaluate the derivative.

  8. EFFECT OF ROOT TEMPERATURE ON SINK STRENGTH OF TUBEROUS ROOT IN SWEET POTATO PLANTS (IPOMOEA BATATAS LAM.)

    OpenAIRE

    Eguchi, Toshihiko; Kitano, Masaharu; Eguchi, Hiromi

    1994-01-01

    Eflect of root temperature on sink strength of tuberous root in sweet potato plants was examined at root temperatures of 20 to 32℃ under a constant air condition of 28℃ and 70% RH. Dry weight, volume and dry matter content of tuberous root became higher at root temperatures of 24 to 26℃. However, sink strength of tuberous root, which was estimated by its dry weight per unit leaf area, was highest at a root temperature of 24℃ possibly because of lower sink activities at lower root temperatures...

  9. 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

  10. Getting to the roots of it: Genetic and hormonal control of root architecture

    OpenAIRE

    Janelle Kang Hui Jung; Susan Rutherford McCouch

    2013-01-01

    Root system architecture (RSA)--the spatial configuration of a root system--is an important developmental and agronomic trait, with implications for overall plant architecture, growth rate and yield, abiotic stress resistance, nutrient uptake, and developmental plasticity in response to environmental changes. Root architecture is modulated by intrinsic, hormone-mediated pathways, intersecting with pathways that perceive and respond to external, environmental signals. The recent developmen...

  11. Short-term tissue response to potential root-end filling materials in infected root canals.

    Science.gov (United States)

    Chong, B S; Pitt Ford, T R; Kariyawasam, S P

    1997-07-01

    The short-term tissue responses to two potential root-end filling materials, a light-cured glass ionomer cement (Vitrebond) and a reinforced zinc oxide-eugenol cement (Kalzinol), were compared with that to amalgam using a previously devised experimental model. In 24 premolar teeth of beagle dogs (47 roots), a collection of endodontic pathogenic bacteria was first inoculated into the root canals to induce periradicular lesions. On each root, an apicoectomy was performed and root-end cavities prepared to receive fillings of each material. The teeth and surrounding jaw were removed after 2 weeks (23 roots) and 1 week (24 roots); they were then prepared for histological examination. The tissue response to amalgam fillings after 2 weeks and 1 week was marked by moderate or severe inflammation on all roots, and extended to 0.5 mm in 15 out of 16 roots. In contrast, after 2 weeks, the majority of roots filled with Kalzinol showed little or moderate inflammation, while the tissue response to Vitrebond was the best of the three materials, and was also the least extensive. After 1 week, the overall best tissue response was with Vitrebond, followed by Kalzinol. The differences between materials for both time periods with either none or few inflammatory cells when compared with that with either moderate or severe inflammation were not statistically significant (P inflammation or inflammation extending inflammation extending > 0.2 mm ( 0.5 mm) were statistically significant (P inflammation adjacent to the root-end filling, even though there were intersample variations, there was little overall difference in the temporal and qualitative healing response to Vitrebond and Kalzinol. Both Vitrebond and Kalzinol have potential as root-end filling materials, as the tissue response was considerably more favourable than that to amalgam even in the short-term.

  12. Evaluation of the anatomical alterations of lower molars mesial root?s apical third

    Directory of Open Access Journals (Sweden)

    FRÖNER Izabel Cristina

    1999-01-01

    Full Text Available The anatomical apex of the mesial root of the lower molars presents a morphological complexity related to the number and shape of the root canals as well as of the apical foramen and isthmus presence. The knowledge of the complexity of the endodontic system of the molar root area is essencial to select more carefully the best instrumentation and obturation technique, to obtain a more successful endodontic therapy.

  13. Roots of Dehn twists about separating curves

    CERN Document Server

    Rajeevsarathy, Kashyap

    2011-01-01

    Let $C$ be a curve in a closed orientable surface $F$ of genus $g \\geq 2$ that separates $F$ into subsurfaces $\\widetilde {F_i}$ of genera $g_i$, for $i = 1,2$. We study the set of roots in $\\Mod(F)$ of the Dehn twist $t_C$ about $C$. All roots arise from pairs of $C_{n_i}$-actions on the $\\widetilde{F_i}$, where $n=\\lcm(n_1,n_2)$ is the degree of the root, that satisfy a certain compatibility condition. The $C_{n_i}$ actions are of a kind that we call nestled actions, and we classify them using tuples that we call data sets. The compatibility condition can be expressed by a simple formula, allowing a classification of all roots of $t_C$ by compatible pairs of data sets. We use these data set pairs to classify all roots for $g = 2$ and $g = 3$. We show that there is always a root of degree at least $2g^2+2g$, while $n \\leq 4g^2+2g$. We also give some additional applications.

  14. Extracellular DNA: the tip of root defenses?

    Science.gov (United States)

    Hawes, Martha C; Curlango-Rivera, Gilberto; Wen, Fushi; White, Gerard J; Vanetten, Hans D; Xiong, Zhongguo

    2011-06-01

    This review discusses how extracellular DNA (exDNA) might function in plant defense, and at what level(s) of innate immunity this process might operate. A new role for extracellular factors in mammalian defense has been described in a series of studies. These studies reveal that cells including neutrophils, eosinophils, and mast cells produce 'extracellular traps' (ETs) consisting of histone-linked exDNA. When pathogens are attracted to such ETs, they are trapped and killed. When the exDNA component of ETs is degraded, trapping is impaired and resistance against invasion is reduced. Conversely, mutation of microbial genes encoding exDNases that degrade exDNA results in loss of virulence. This discovery that exDNases are virulence factors opens new avenues for disease control. In plants, exDNA is required for defense of the root tip. Innate immunity-related proteins are among a group of >100 proteins secreted from the root cap and root border cell populations. Direct tests revealed that exDNA also is rapidly synthesized and exported from the root tip. When this exDNA is degraded by the endonuclease DNase 1, root tip resistance to fungal infection is lost; when the polymeric structure is degraded more slowly, by the exonuclease BAL31, loss of resistance to fungal infection is delayed accordingly. The results suggest that root border cells may function in a manner analogous to that which occurs in mammalian cells.

  15. Vertical root fractures and their management

    Science.gov (United States)

    Khasnis, Sandhya Anand; Kidiyoor, Krishnamurthy Haridas; Patil, Anand Basavaraj; Kenganal, Smita Basavaraj

    2014-01-01

    Vertical root fractures associated with endodontically treated teeth and less commonly in vital teeth represent one of the most difficult clinical problems to diagnose and treat. In as much as there are no specific symptoms, diagnosis can be difficult. Clinical detection of this condition by endodontists is becoming more frequent, where as it is rather underestimated by the general practitioners. Since, vertical root fractures almost exclusively involve endodontically treated teeth; it often becomes difficult to differentiate a tooth with this condition from an endodontically failed one or one with concomitant periodontal involvement. Also, a tooth diagnosed for vertical root fracture is usually extracted, though attempts to reunite fractured root have been done in various studies with varying success rates. Early detection of a fractured root and extraction of the tooth maintain the integrity of alveolar bone for placement of an implant. Cone beam computed tomography has been shown to be very accurate in this regard. This article focuses on the diagnostic and treatment strategies, and discusses about predisposing factors which can be useful in the prevention of vertical root fractures. PMID:24778502

  16. Tomato Root Response to Subsurface Drip Irrigation

    Institute of Scientific and Technical Information of China (English)

    ZHUGE Yu-Ping; ZHANG Xu-Dong; ZHANG Yu-Long; LI Jun; YANG Li-Juan; HUANG Yi; LIU Ming-Da

    2004-01-01

    Four depth treatments of subsurface drip irrigation pipes were designated as 1) at 20,2) 30 and 3) 40 cm depths all with a drip-proof flumes underneath,and 4) at 30 cm without a drip-proof flume to investigate the responses of a tomato root system to different technical parameters of subsurface drip irrigation in a glass greenhouse,to evaluate tomato growth as affected by subsurface drip irrigation,and to develop an integrated subsurface drip irrigation method for optimal tomato yield and water use in a glass greenhouse. Tomato seedlings were planted above the subsurface drip irrigation pipe. Most of the tomato roots in treatment 1 were found in the top 0-20 cm soil depth with weak root activity but with yield and water use efficiency (WUE) significantly less (P ---- 0.05) than treatment 2; root activity and tomato yield were significantly higher (P = 0.05) with treatment 3 compared to treatment 1; and with treatment 2 the tomato roots and shoots grew harmoniously with root activity,nutrient uptake,tomato yield and WUE significantly higher (P= 0.05) or as high as the other treatments. These findings suggested that subsurface drip irrigation with pipes at 30 cm depth with a drip-proof flume placed underneath was best for tomato production in greenhouses. In addition,the irrigation interval should be about 7-8 days and the irrigation rate should be set to 225 m3 ha-1 per event.

  17. Adaptive significance of root grafting in trees

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C.; Jones, R.

    1988-12-31

    Root grafting has long been observed in forest trees but the adaptive significance of this trait has not been fully explained. Various authors have proposed that root grafting between trees contributes to mechanical support by linking adjacent root systems. Keeley proposes that this trait would be of greatest advantage in swamps where soils provide poor mechanical support. He provides as evidence a greenhouse study of Nyssa sylvatica Marsh in which seedlings of swamp provenance formed between-individual root grafts more frequently than upland provenance seedlings. In agreement with this within-species study, Keeley observed that arid zone species rarely exhibit grafts. Keeley also demonstrated that vines graft less commonly than trees, and herbs never do. Since the need for mechanical support coincides with this trend, these data seem to support his model. In this paper, the authors explore the mechanisms and ecological significance of root grafting, leading to predictions of root grafting incidence. Some observations support and some contradict the mechanical support hypothesis.

  18. Defining the core Arabidopsis thaliana root microbiome

    Science.gov (United States)

    Gehring, Jase; Malfatti, Stephanie; Tremblay, Julien; Engelbrektson, Anna; Kunin, Victor; del Rio, Tijana Glavina; Edgar, Robert C.; Eickhorst, Thilo; Ley, Ruth E.; Hugenholtz, Philip; Tringe, Susannah Green; Dangl, Jeffery L.

    2014-01-01

    Land plants associate with a root microbiota distinct from the complex microbial community present in surrounding soil. The microbiota colonizing therhizosphere(immediately surroundingthe root) and the endophytic compartment (within the root) contribute to plant growth, productivity, carbon sequestration and phytoremediation1-3. Colonization of the root occurs despite a sophisticated plant immune system4,5, suggesting finely tuned discrimination of mutualists and commensals from pathogens. Genetic principles governing the derivation of host-specific endophyte communities from soil communities are poorly understood. Here we report the pyrosequencing of the bacterial 16S ribosomal RNA gene of more than 600 Arabidopsis thaliana plants to test the hypotheses that the root rhizosphere and endophytic compartment microbiota of plants grown under controlled conditions in natural soils are sufficiently dependent on the host to remain consistent across different soil types and developmental stages, and sufficiently dependent on host genotype to vary between inbred Arabidopsis accessions. We describe different bacterial communities in two geochemically distinct bulk soils and in rhizosphere and endophytic compartments prepared from roots grown in these soils. The communities in each compartment are strongly influenced by soil type. Endophytic compartments from both soils feature overlapping, low-complexity communities that are markedly enriched in Actinobacteria and specific families from other phyla, notably Proteobacteria. Some bacteria vary quantitatively between plants of different developmental stage and genotype. Our rigorous definition of an endophytic compartment microbiome should facilitate controlled dissection of plantmicrobe interactions derived from complex soil communities. PMID:22859206

  19. 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

    the length of apicectomy and calculated the loss of root length and changes of RCR after apical surgery. METHODS: In a prospective clinical study, cone-beam computed tomography scans were taken preoperatively and postoperatively. From these images, the crown and root lengths of 61 roots (54 teeth in 47.......58 ± 1.43 mm (relative to the CBL). This amounted to a loss of 33.2% of clinical and 26% of anatomic root length. There was an overall significant difference between the tooth groups (P

  20. A New Anatomically Based Nomenclature for the Roots and Root Canals—Part 2: Mandibular Molars

    Directory of Open Access Journals (Sweden)

    Denzil Valerian Albuquerque

    2012-01-01

    Full Text Available Several terminologies have been employed in the dental literature to describe the roots and root canal systems of mandibular molars with no consensus being arrived at, thus far. The anatomical relation of roots and their root canals were identified and a naming system was formulated. The proposed nomenclature attempts to make certain essential modifications to the traditional approach to accommodate the naming of various aberrations presented in mandibular molars. A simple, yet extensive nomenclature system has been proposed that appropriately names the internal and external morphology of mandibular molars.

  1. Plant root tortuosity: an indicator of root path formation in soil with different composition and density

    Science.gov (United States)

    Popova, Liyana; van Dusschoten, Dagmar; Nagel, Kerstin A.; Fiorani, Fabio; Mazzolai, Barbara

    2016-01-01

    Background and Aims Root soil penetration and path optimization are fundamental for root development in soil. We describe the influence of soil strength on root elongation rate and diameter, response to gravity, and root-structure tortuosity, estimated by average curvature of primary maize roots. Methods Soils with different densities (1·5, 1·6, 1·7 g cm−3), particle sizes (sandy loam; coarse sand mixed with sandy loam) and layering (monolayer, bilayer) were used. In total, five treatments were performed: Mix_low with mixed sand low density (three pots, 12 plants), Mix_medium - mixed sand medium density (three pots, 12 plants), Mix_high - mixed sand high density (three pots, ten plants), Loam_low sandy loam soil low density (four pots, 16 plants), and Bilayer with top layer of sandy loam and bottom layer mixed sand both of low density (four pots, 16 plants). We used non-invasive three-dimensional magnetic resonance imaging to quantify effects of these treatments. Key Results Roots grew more slowly [root growth rate (mm h–1); decreased 50 %] with increased diameters [root diameter (mm); increased 15 %] in denser soils (1·7 vs. 1·5 g cm–3). Root response to gravity decreased 23 % with increased soil compaction, and tortuosity increased 10 % in mixed sand. Response to gravity increased 39 % and tortuosity decreased 3 % in sandy loam. After crossing a bilayered–soil interface, roots grew more slowly, similar to roots grown in soil with a bulk density of 1·64 g cm–3, whereas the actual experimental density was 1·48±0·02 g cm–3. Elongation rate and tortuosity were higher in Mix_low than in Loam_low. Conclusions The present study increases our existing knowledge of the influence of physical soil properties on root growth and presents new assays for studying root growth dynamics in non-transparent media. We found that root tortuosity is indicative of root path selection, because it could result from both mechanical deflection and

  2. A new Approach for Quantifying Root-Reinforcement of Streambanks: the RipRoot Model

    Science.gov (United States)

    Pollen, N. L.; Simon, A.

    2003-12-01

    Riparian vegetation plays an important role in controlling geotechnical and fluvial processes acting along and within streambanks through the binding effects of roots. Quantification of this mechanical effect is therefore essential to accurately model streambank stability. Until now, most attempts to include the effects of root reinforcement by riparian vegetation have used root-cohesion values estimated using the Wu et al. (1979) equation, requiring the tensile strengths and diameters of the roots crossing the potential shear-plane. However, the Wu et al. equation is a static model that assumes that all roots break, and that they all break simultaneously. Field observations and laboratory experiments have shown that in reality the roots do not all break simultaneously, and that the breaking of roots during mass failure is in fact a dynamic process. Static models such as the Wu et al. equation are therefore likely to produce overestimations of cohesion due to roots. As a response to this concern, a dynamic root reinforcement model (RipRoot) was developed, based on the concepts of fiber bundle models (FBM's) used in materials science. Within the model the root-soil system is loaded incrementally resulting in progressive root breaking and redistribution of stresses from the broken roots to the remaining intact roots in the soil matrix. The redistribution and loading process continues until either all of the roots have broken, or equilibrium is reached where the root network supports the driving force imposed on the bank. The increase in bank cohesion using the static Wu et al. equation are 18% to 38% higher than RipRoot for riparian tree species, including Black Willow, Sandbar Willow, Cottonwood, River Birch and Eastern Sycamore, and 49% higher for Switch Grass. These variations in cohesion values can have a significant impact on streambank Factor of Safety (Fs) values calculated using the Simon et al. (2000) bank-stability model. For example, a 3m high silt

  3. Modelling water uptake efficiency of root systems

    Science.gov (United States)

    Leitner, Daniel; Tron, Stefania; Schröder, Natalie; Bodner, Gernot; Javaux, Mathieu; Vanderborght, Jan; Vereecken, Harry; Schnepf, Andrea

    2016-04-01

    Water uptake is crucial for plant productivity. Trait based breeding for more water efficient crops will enable a sustainable agricultural management under specific pedoclimatic conditions, and can increase drought resistance of plants. Mathematical modelling can be used to find suitable root system traits for better water uptake efficiency defined as amount of water taken up per unit of root biomass. This approach requires large simulation times and large number of simulation runs, since we test different root systems under different pedoclimatic conditions. In this work, we model water movement by the 1-dimensional Richards equation with the soil hydraulic properties described according to the van Genuchten model. Climatic conditions serve as the upper boundary condition. The root system grows during the simulation period and water uptake is calculated via a sink term (after Tron et al. 2015). The goal of this work is to compare different free software tools based on different numerical schemes to solve the model. We compare implementations using DUMUX (based on finite volumes), Hydrus 1D (based on finite elements), and a Matlab implementation of Van Dam, J. C., & Feddes 2000 (based on finite differences). We analyse the methods for accuracy, speed and flexibility. Using this model case study, we can clearly show the impact of various root system traits on water uptake efficiency. Furthermore, we can quantify frequent simplifications that are introduced in the modelling step like considering a static root system instead of a growing one, or considering a sink term based on root density instead of considering the full root hydraulic model (Javaux et al. 2008). References Tron, S., Bodner, G., Laio, F., Ridolfi, L., & Leitner, D. (2015). Can diversity in root architecture explain plant water use efficiency? A modeling study. Ecological modelling, 312, 200-210. Van Dam, J. C., & Feddes, R. A. (2000). Numerical simulation of infiltration, evaporation and shallow

  4. Propagação vegetativa de Platanus acerifolia Ait: (II efeito da aplicação de zinco, boro e ácido indolbutírico no enraizamento de estacas Vegetative propagation of Platanus acerifolia Ait: (II effect of zinc,boron, and indolbutiric acid on rooting of cuttings

    Directory of Open Access Journals (Sweden)

    Fernando Teixeira Nicoloso

    1999-09-01

    husk, 1:1 v/v, both washed. The experiment was conducted during 110 days under intermittent artificial mist conditions. The evaluated parameters were: length and number of primary adventitious roots, dry weight of adventitious roots, and percentage of rooting. The results show that Zn and B have no influence on the rooting, and the addition of IBA on thin basal semi-herbaceous cuttings reduces the percentage of rooting and increase the number of roots.

  5. D-Root: a system for cultivating plants with the roots in darkness or under different light conditions.

    Science.gov (United States)

    Silva-Navas, Javier; Moreno-Risueno, Miguel A; Manzano, Concepción; Pallero-Baena, Mercedes; Navarro-Neila, Sara; Téllez-Robledo, Bárbara; Garcia-Mina, Jose M; Baigorri, Roberto; Gallego, Francisco Javier; del Pozo, Juan C

    2015-10-01

    In nature roots grow in the dark and away from light (negative phototropism). However, most current research in root biology has been carried out with the root system grown in the presence of light. Here, we have engineered a device, called Dark-Root (D-Root), to grow plants in vitro with the aerial part exposed to the normal light/dark photoperiod while the roots are in the dark or exposed to specific wavelengths or light intensities. D-Root provides an efficient system for cultivating a large number of seedlings and easily characterizing root architecture in the dark. At the morphological level, root illumination shortens root length and promotes early emergence of lateral roots, therefore inducing expansion of the root system. Surprisingly, root illumination also affects shoot development, including flowering time. Our analyses also show that root illumination alters the proper response to hormones or abiotic stress (e.g. salt or osmotic stress) and nutrient starvation, enhancing inhibition of root growth. In conclusion, D-Root provides a growing system closer to the natural one for assaying Arabidopsis plants, and therefore its use will contribute to a better understanding of the mechanisms involved in root development, hormonal signaling and stress responses.

  6. Tissue response to potential root-end filling materials in infected root canals.

    Science.gov (United States)

    Chong, B S; Ford, T R; Kariyawasam, S P

    1997-03-01

    The tissue responses to two potential root-end filling materials, a light-cured glass ionomer cement (Vitrebond) and a reinforced zinc oxide-eugenol cement (Kalzinol) were compared with that to amalgam. In 27 premolar teeth of beagle dogs (54 roots), a collection of endodontic pathogenic bacteria was first inoculated into the root canals to induce periapical lesions. On each root, an apicectomy was performed and root-end cavities prepared to receive fillings of each material. The teeth and surrounding jaw were removed after 8 weeks (24 roots) and 4 weeks (30 roots); and they were prepared for histological examination. The tissue response to amalgam fillings after 4 and 8 weeks was marked by moderate or severe inflammation on all roots, and extended > 0.5 mm in 10 out of 18 roots. In contrast, after 8 weeks, the majority of roots filled with Kalzinol showed little or moderate inflammation while the tissue response to Vitrebond was the best of the three materials, and was also less extensive. After 4 weeks, the overall best tissue response was with Kalzinol, followed closely by Vitrebond. The differences between materials for both time periods with either none or few inflammatory cells when compared with that with either moderate or severe inflammation were statistically significant (P inflammation or inflammation extending inflammation extending > 0.2 mm ( 0.5 mm) were statistically significant (P < 0.01). Both Vitrebond and Kalzinol have potential as root-end filling materials as the tissue response was considerably more favourable than that to amalgam.

  7. Mercury content of sprouts and harvested roots from treated sweet potato mother roots. [Ipomoea batatas

    Energy Technology Data Exchange (ETDEWEB)

    Huisingh, D.; Nielsen, L.W.

    1972-01-01

    Mercury containing fungicides have been used extensively for seed and root disease control, but data on the fate of the mercury (Hg) are scarce. Experiments were designed to see if Hg applied to propagative sweet potato roots increased the Hg-content of edible roots. Roots were treated with Semesan Bel(hydroxymercurinitrophenol + hydroxymercurichlorophenol), Mertect (Thiabendazole: 2-(4-Thiazolyl)-benzimidazole), or Botran (2,6-Dichloro-4-nitroanaline) at recommended rates or with water. Treated roots were bedded into sandy loam soil, and the plants were harvested at 2 and 3 months after bedding. Some sprouts transplanted at 2 months were grown to maturity, and the harvested roots were analyzed. Hg analyses were performed by flameless atomic absorption. Roots treated prior to planting with Semesan Bel, Mertect, Botran, and water contained 23.0, 0.05, 0.03 and 0.03 ..mu..g/g dry wt, respectively. At the 2-month harvest, the leaves and stems of the Semesan Bel-treated plants contained 5 times more Hg than those of the other treatments. By the 3-month harvest, the amount of Hg in plant leaves and stems from Hg-treated roots was 2 to 3 times that of the others. Fall harvested fleshy roots contained 0.03, 0.02, 0.03, and 0.03 ..mu..g/g dry wt Hg for the Semesan Bel, Mertect, Botran, and water treatments, respectively. This demonstrates that the Hg applied to the mother root was translocated to the new plant, but little if any was translocated to the new fleshy roots.

  8. How can science education foster students' rooting?

    Science.gov (United States)

    Østergaard, Edvin

    2015-06-01

    The question of how to foster rooting in science education points towards a double challenge; efforts to prevent (further) uprooting and efforts to promote rooting/re-rooting. Wolff-Michael Roth's paper discusses the uprooting/rooting pair of concepts, students' feeling of alienation and loss of fundamental sense of the earth as ground, and potential consequences for teaching science in a rooted manner. However, the argumentation raises a number of questions which I try to answer. My argumentation rests on Husserl's critique of science and the "ontological reversal", an ontological position where abstract models from science are considered as more real than the everyday reality itself, where abstract, often mathematical, models are taken to be the real causes behind everyday experiences. In this paper, measures towards an "ontological re-reversal" are discussed by drawing on experiences from phenomenon-based science education. I argue that perhaps the most direct and productive way of promoting rooting in science class is by intentionally cultivating the competencies of sensing and aesthetic experience. An aesthetic experience is defined as a precognitive, sensuous experience, an experience that is opened up for through sensuous perception. Conditions for rooting in science education is discussed against three challenges: Restoring the value of aesthetic experience, allowing time for open inquiry and coping with curriculum. Finally, I raise the question whether dimensions like "reality" or "nature" are self-evident for students. In the era of constructivism, with its focus on cognition and knowledge building, the inquiry process itself has become more important than the object of inquiry. I argue that as educators of science teachers we have to emphasize more explicitly "the nature of nature" as a field of exploration.

  9. Ecological Hypothesis of Dentin and Root Caries.

    Science.gov (United States)

    Takahashi, Nobuhiro; Nyvad, Bente

    2016-01-01

    Recent advances regarding the caries process indicate that ecological phenomena induced by bacterial acid production tilt the de- and remineralization balance of the dental hard tissues towards demineralization through bacterial acid-induced adaptation and selection within the microbiota - from the dynamic stability stage to the aciduric stage via the acidogenic stage [Takahashi and Nyvad, 2008]. Dentin and root caries can also be partly explained by this hypothesis; however, the fact that these tissues contain a considerable amount of organic material suggests that protein degradation is involved in caries formation. In this review, we compiled relevant histological, biochemical, and microbiological information about dentin/root caries and refined the hypothesis by adding degradation of the organic matrix (the proteolytic stage) to the abovementioned stages. Bacterial acidification not only induces demineralization and exposure of the organic matrix in dentin/root surfaces but also activation of dentin-embedded and salivary matrix metalloproteinases and cathepsins. These phenomena initiate degradation of the demineralized organic matrix in dentin/root surfaces. While a bacterial involvement has never been confirmed in the initial degradation of organic material, the detection of proteolytic/amino acid-degrading bacteria and bacterial metabolites in dentin and root caries suggests a bacterial digestion and metabolism of partly degraded matrix. Moreover, bacterial metabolites might induce pulpitis as an inflammatory/immunomodulatory factor. Root and dentin surfaces are always at risk of becoming demineralized in the oral cavity, and exposed organic materials can be degraded by host-derived proteases contained in saliva and dentin itself. New approaches to the prevention and treatment of root/dentin caries are required. PMID:27458979

  10. 21 CFR 872.3810 - Root canal post.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Root canal post. 872.3810 Section 872.3810 Food... DEVICES DENTAL DEVICES Prosthetic Devices § 872.3810 Root canal post. (a) Identification. A root canal... of the platinum group intended to be cemented into the root canal of a tooth to stabilize and...

  11. Cold temperature delays wound healing in postharvest sugarbeet roots

    Science.gov (United States)

    Storage temperature affects the rate and extent of wound-healing in a number of root and tuber crops. The effect of storage temperature on wound-healing in sugarbeet (Beta vulgaris L.) roots, however, is largely unknown. Wound-healing of sugarbeet roots was investigated using surface-abraded roots s...

  12. Effects of Cu2 + on the Growth of the Adventitious Buds of Thyme serpyllum in in vitro Culture and Their Essential Oil%Cu2+对离体培养的红花百里香不定芽生长及挥发油的影响

    Institute of Scientific and Technical Information of China (English)

    徐治朋; 李晓东; 鲁朝晖; 李凌

    2016-01-01

    The adventitious buds of Thyme serpyllum induced in in vitro culture were treated by Cu 2 + at different concentrations ,and then various indicators were measured to investigate effect of Cu 2 + on their grow th and essential oil .The results showed that low concentrations of Cu 2 + facilitated the proliferation of the adventitious buds while high concentrations of Cu 2 + inhibited it .Of all the concentrations of CuCl2 studied ,the treatment of 50μmol/L gave the highest proliferation coefficient (20.35) and the highest es‐sential oil content (27.25 ‰ ) ,which was 23.98% more than the control ,and the color of the essential oil was deeper .Therefore ,the study showed that the addition of Cu2 + at a suitable concentration could pro‐mote the proliferation of adventitious buds of T. serpyllum and enhance their resistance ,and promote the accumulation of essential oil and change its composition .%以离体培养的红花百里香不定芽为材料,采用不同浓度 CuCl2处理,测定不定芽的各种指标,研究 Cu2+对红花百里香不定芽的增殖生长及挥发油的影响.结果表明,低浓度的 CuCl2可以促进红花百里香不定芽的增殖生长,而高浓度的 CuCl2起抑制作用;其中50μmol/L 的 CuCl2对不定芽的增殖效果最好,增殖系数高达20.35,精油含量达到27.25‰,提高了23.98%,且颜色更深.说明一定浓度的 Cu2+能促进红花百里香不定芽的增殖生长,增强其抗逆性,促进百里香挥发油的合成积累,改变其成分组成.

  13. How up- or downslope anchoring affects root reinforcement

    Science.gov (United States)

    Giadrossich, Filippo; Schwarz, Massimiliano; Cohen, Denis; Niedda, Marcello

    2016-04-01

    Root reinforcement is important for slope stability. In addition to the important contribution of roots to shear strength along the slip surface, root networks are also recognized to impart stabilization through lateral (parallel to slope) redistribution of forces under tension. The most common method to measure lateral root reinforcement is a pullout test where one root or a bundle of root is pulled out of the soil matrix. This condition represents the case where roots within the mass of a landslide slip out from the upper stable part of the slope. There is also, however, the situation where roots anchored in the upper stable part of the slope slip out from the sliding mass. In the latter it is difficult to quantify root reinforcement and no study has discussed this mechanism. We carried out a new series of laboratory and field experiments using Douglas fir (Pseudotsuga menziesii) roots to quantify how up- or downslope anchoring affects root reinforcement. In addition, we carried out new field pullout tests on coarse roots (larger that 2 mm in diameter, up to 47 mm). Then, considering the state-of-the-art of root reinforcement modeling (the Root Bundle Model), we integrated results from our measurements into the model to verify the magnitude of this effect on overall root reinforcement at the stand scale. Results indicate that the ratio between pullout force and force transferred to the root during soil slip ranges between 0.5 and 1. This indicates that measured pullout force always overestimate the contribution of lateral slipping out roots in situations where the soil slide from anchored roots. This is general the case for root with diameter up to 3-4 mm. Root-size distribution is also a key factor influencing root reinforcement at the forest-stand scale. As most coarse roots break along tension cracks while fine roots slip out, the effect discussed in this study on root reinforcement modeling is negligible when coarse-root diameter classes are represented. Our

  14. Effect of root canal preparation, type of endodontic post and mechanical cycling on root fracture strength

    Directory of Open Access Journals (Sweden)

    Marília Pivetta RIPPE

    2014-06-01

    Full Text Available Objective: To evaluate the impact of the type of root canal preparation, intraradicular post and mechanical cycling on the fracture strength of roots. Material and Methods: eighty human single rooted teeth were divided into 8 groups according to the instruments used for root canal preparation (manual or rotary instruments, the type of intraradicular post (fiber posts- FRC and cast post and core- CPC and the use of mechanical cycling (MC as follows: Manual and FRC; Manual, FRC and MC; Manual and CPC; Manual, CPC and MC; Rotary and FRC; Rotary, FRC and MC; Rotary and CPC; Rotary, CPC and MC. The filling was performed by lateral compactation. All root canals were prepared for a post with a 10 mm length, using the custom #2 bur of the glass fiber post system. For mechanical cycling, the protocol was applied as follows: an angle of incidence of 45°, 37°C, 88 N, 4 Hz, 2 million pulses. All groups were submitted to fracture strength test in a 45° device with 1 mm/ min cross-head speed until failure occurred. Results: The 3-way ANOVA showed that the root canal preparation strategy (p<0.03 and post type (p<0.0001 affected the fracture strength results, while mechanical cycling (p=0.29 did not. Conclusion: The root canal preparation strategy only influenced the root fracture strength when restoring with a fiber post and mechanical cycling, so it does not seem to be an important factor in this scenario.

  15. Roots Withstanding their Environment: Exploiting Root System Architecture Responses to Abiotic Stress to Improve Crop Tolerance.

    Science.gov (United States)

    Koevoets, Iko T; Venema, Jan Henk; Elzenga, J Theo M; Testerink, Christa

    2016-01-01

    To face future challenges in crop production dictated by global climate changes, breeders and plant researchers collaborate to develop productive crops that are able to withstand a wide range of biotic and abiotic stresses. However, crop selection is often focused on shoot performance alone, as observation of root properties is more complex and asks for artificial and extensive phenotyping platforms. In addition, most root research focuses on development, while a direct link to the functionality of plasticity in root development for tolerance is often lacking. In this paper we review the currently known root system architecture (RSA) responses in Arabidopsis and a number of crop species to a range of abiotic stresses, including nutrient limitation, drought, salinity, flooding, and extreme temperatures. For each of these stresses, the key molecular and cellular mechanisms underlying the RSA response are highlighted. To explore the relevance for crop selection, we especially review and discuss studies linking root architectural responses to stress tolerance. This will provide a first step toward understanding the relevance of adaptive root development for a plant's response to its environment. We suggest that functional evidence on the role of root plasticity will support breeders in their efforts to include root properties in their current selection pipeline for abiotic stress tolerance, aimed to improve the robustness of crops. PMID:27630659

  16. Pea-root exudates and their effect upon root-nodule bacteria

    NARCIS (Netherlands)

    Egeraat, van A.W.S.M.

    1972-01-01

    The main purpose of this investigation was to study the exudation (mechanism, sites) of various compounds by roots of pea seedlings in relation to the growth of Rhizobium leguminosarum.Chapter 1 gives a survey of the literature pertaining to plant-root exudates and their influence upon soil microorg

  17. Root system markup language: toward a unified root architecture description language.

    Science.gov (United States)

    Lobet, Guillaume; Pound, Michael P; Diener, Julien; Pradal, Christophe; Draye, Xavier; Godin, Christophe; Javaux, Mathieu; Leitner, Daniel; Meunier, Félicien; Nacry, Philippe; Pridmore, Tony P; Schnepf, Andrea

    2015-03-01

    The number of image analysis tools supporting the extraction of architectural features of root systems has increased in recent years. These tools offer a handy set of complementary facilities, yet it is widely accepted that none of these software tools is able to extract in an efficient way the growing array of static and dynamic features for different types of images and species. We describe the Root System Markup Language (RSML), which has been designed to overcome two major challenges: (1) to enable portability of root architecture data between different software tools in an easy and interoperable manner, allowing seamless collaborative work; and (2) to provide a standard format upon which to base central repositories that will soon arise following the expanding worldwide root phenotyping effort. RSML follows the XML standard to store two- or three-dimensional image metadata, plant and root properties and geometries, continuous functions along individual root paths, and a suite of annotations at the image, plant, or root scale at one or several time points. Plant ontologies are used to describe botanical entities that are relevant at the scale of root system architecture. An XML schema describes the features and constraints of RSML, and open-source packages have been developed in several languages (R, Excel, Java, Python, and C#) to enable researchers to integrate RSML files into popular research workflow.

  18. Roots Withstanding their Environment: Exploiting Root System Architecture Responses to Abiotic Stress to Improve Crop Tolerance

    Science.gov (United States)

    Koevoets, Iko T.; Venema, Jan Henk; Elzenga, J. Theo. M.; Testerink, Christa

    2016-01-01

    To face future challenges in crop production dictated by global climate changes, breeders and plant researchers collaborate to develop productive crops that are able to withstand a wide range of biotic and abiotic stresses. However, crop selection is often focused on shoot performance alone, as observation of root properties is more complex and asks for artificial and extensive phenotyping platforms. In addition, most root research focuses on development, while a direct link to the functionality of plasticity in root development for tolerance is often lacking. In this paper we review the currently known root system architecture (RSA) responses in Arabidopsis and a number of crop species to a range of abiotic stresses, including nutrient limitation, drought, salinity, flooding, and extreme temperatures. For each of these stresses, the key molecular and cellular mechanisms underlying the RSA response are highlighted. To explore the relevance for crop selection, we especially review and discuss studies linking root architectural responses to stress tolerance. This will provide a first step toward understanding the relevance of adaptive root development for a plant’s response to its environment. We suggest that functional evidence on the role of root plasticity will support breeders in their efforts to include root properties in their current selection pipeline for abiotic stress tolerance, aimed to improve the robustness of crops. PMID:27630659

  19. Compensation in Root Water Uptake Models Combined with Three-Dimensional Root Length Density Distribution

    NARCIS (Netherlands)

    Heinen, M.

    2014-01-01

    A three-dimensional root length density distribution function is introduced that made it possible to compare two empirical uptake models with a more mechanistic uptake model. Adding a compensation component to the more empirical model resulted in predictions of root water uptake distributions simila

  20. Redirection of auxin flow in Arabidopsis thaliana roots after infection by root-knot nematodes

    NARCIS (Netherlands)

    Kyndt, Tina; Goverse, Aska; Haegeman, Annelies; Warmerdam, Sonja; Wanjau, Cecilia; Jahani, Mona; Engler, Gilbert; Almeida Engler, De Janice; Gheysen, Godelieve

    2016-01-01

    Plant-parasitic root-knot nematodes induce the formation of giant cells within the plant root, and it has been recognized that auxin accumulates in these feeding sites. Here, we studied the role of the auxin transport system governed by AUX1/LAX3 influx proteins and different PIN efflux proteins dur

  1. Indução e cultivo in vitro de gemas adventícias em segmentos de epicótilo de laranja-azeda In vitro induction and culture of adventitious buds in epicotyl segments of sour orange

    Directory of Open Access Journals (Sweden)

    Rosely Pereira da Silva

    2008-10-01

    Full Text Available O objetivo deste trabalho foi avaliar a indução e a formação de gemas adventícias em explantes de laranja-azeda, pelo uso de fitorreguladores. Em experimentos de organogênese in vitro foram avaliados 6-benzilaminopurina (BAP, thidiazuron (TDZ e cinetina (CIN, em diferentes concentrações e sob duas condições de luminosidade; BAP e CIN combinados ou não com ácido naftalenoacético (ANA; e BAP e CIN isoladamente ou combinados entre si. Segmentos de epicótilo de 1 cm de comprimento, provenientes de plântulas de laranja-azeda germinadas in vitro, foram utilizados como explantes. Para induzir a formação de gemas, os segmentos foram cultivados em meio MT com ou sem adição de fitorreguladores. O material foi cultivado a 27ºC em ausência de luz por 30 dias, seguidos de fotoperíodo de 16 horas. O delineamento experimental foi inteiramente casualizado, com quatro ou cinco repetições, a depender do experimento e, cada repetição foi constituída de placa de Petri com 20 explantes. Após 60 ou 70 dias de cultivo foram avaliados o percentual de explantes responsivos e o número de gemas por explante. A adição de BAP ao meio de cultura, combinada ou não com ANA, e em combinações com CIN promovem melhor resposta organogênica.The objective of this work was to evaluate the induction and formation of adventitious buds in sour orange explants through the use of plant regulators. In vitro organogenesis experiments were conducted to evaluate the effect of BAP, TDZ, and KIN in different concentrations and under two light conditions; BAP and KIN, combined or not with NAA; BAP and KIN, separately or in combined concentrations. Sour orange epicotyl segments (1 cm length, from in vitro germinated plants, were used as explants. In order to induce bud formation, the explants were cultured in MT medium with or without the addition of plant regulators. The material was cultivated at 27ºC in the absence of light for 30 days, followed of culture

  2. Chronic nerve root entrapment: compression and degeneration

    Science.gov (United States)

    Vanhoestenberghe, A.

    2013-02-01

    Electrode mounts are being developed to improve electrical stimulation and recording. Some are tight-fitting, or even re-shape the nervous structure they interact with, for a more selective, fascicular, access. If these are to be successfully used chronically with human nerve roots, we need to know more about the possible damage caused by the long-term entrapment and possible compression of the roots following electrode implantation. As there are, to date, no such data published, this paper presents a review of the relevant literature on alternative causes of nerve root compression, and a discussion of the degeneration mechanisms observed. A chronic compression below 40 mmHg would not compromise the functionality of the root as far as electrical stimulation and recording applications are concerned. Additionally, any temporary increase in pressure, due for example to post-operative swelling, should be limited to 20 mmHg below the patient’s mean arterial pressure, with a maximum of 100 mmHg. Connective tissue growth may cause a slower, but sustained, pressure increase. Therefore, mounts large enough to accommodate the root initially without compressing it, or compliant, elastic, mounts, that may stretch to free a larger cross-sectional area in the weeks after implantation, are recommended.

  3. Etiology of phomopsis root rot in soybean

    Directory of Open Access Journals (Sweden)

    Valéria Cecília Ghissi

    2014-09-01

    Full Text Available In a survey of damages caused by soybean root rot to crops in the south of Brazil for several years, a root rot caused by Phomopsis sp has been found with increasing frequency. The primary symptoms are seen when the main root is cut longitudinally, including the death of the wood which shows white coloration and well-defined black lines that do not have a defined format. Thus, based on similarity, it has been called geographic root rot due to its aspect resembling irregular lines that separate regions on a map. In isolations, colonies and alpha spores of Phomopsis have prevailed. Pathogenicity test was done by means of inoculation in the crown of plants cultivated in a growth chamber. The geographic symptoms were reproduced in plants and the fungus Phomopsis sp. was reisolated. In soybean stems naturally infected with pod and stem blight, geographic symptoms caused by Phomopsis phaseoli are found. To the known symptoms on stems, pods and grains, that of root rot caused by P. phaseoli is now added.

  4. Rooting cuttings of yam (Dioscorea spp.

    Directory of Open Access Journals (Sweden)

    Luiz Eduardo Rocha e Silva

    2014-12-01

    Full Text Available The culture of yams (Dioscorea spp. has great importance for the entire Brazilian population, mainly in the Northeast, either by its nutritional or commercial value. This work aimed to study a new method of seedling production of yams by stem cuttings collected from plants with age of 120 days. The experiment was carried out in the CECA/UFAL, in a green house with intermittent fogging, in a fully randomized block design with a factorial 3 × 2 × 2, 12 treatments and 4 replications. Three factors were evaluated: height of the cuttings collection in plant (top, center and bottom, position of the cuttings on the branch (proximal and distal and concentration of Indolebutyric acid (IBA applied (0 and 1 mg/L. The cuttings were planted in plastic trays of 32 cells, containing commercial Bioplant ® substrate. After 30 days, the presence, the number and length of roots was acessed. All variables were subjected to analysis of variance and averages were compared by Tukey test. The results obtained in this study showed that the use of IBA (1 g/L did not influence the rooting process. Cuttings collected in the basal third of the plants in the proximal part of the branches, independent of the concentration of IBA, presented the best results for the percentage of rooting, root number and length of roots per stake.

  5. How tree roots respond to drought

    Directory of Open Access Journals (Sweden)

    Ivano eBrunner

    2015-07-01

    Full Text Available The ongoing climate change is characterised by increased temperatures and altered precipitation patterns. In addition, there has been an increase in both the frequency and intensity of extreme climatic events such as drought. Episodes of drought induce a series of interconnected effects, all of which have the potential to alter the carbon balance of forest ecosystems profoundly at different scales of plant organisation and ecosystem functioning. During recent years, considerable progress has been made in the understanding of how aboveground parts of trees respond to drought and how these responses affect carbon assimilation. In contrast, processes of belowground parts are relatively underrepresented in research on climate change. In this review, we describe current knowledge about responses of tree roots to drought. Tree roots are capable of responding to drought through a variety of strategies that enable them to avoid and tolerate stress. Responses include root biomass adjustments, anatomical alterations, and physiological acclimations. The molecular mechanisms underlying these responses are characterized to some extent, and involve stress signalling and the induction of numerous genes, leading to the activation of tolerance pathways. In addition, mycorrhizas seem to play important protective roles. The current knowledge compiled in this review supports the view that tree roots are well equipped to withstand drought situations and maintain morphological and physiological functions as long as possible. Further, the reviewed literature demonstrates the important role of tree roots in the functioning of forest ecosystems and highlights the need for more research in this emerging field.

  6. Visualizing Rhizosphere Soil Structure Around Living Roots

    Science.gov (United States)

    Menon, M.; Berli, M.; Ghezzehei, T. A.; Nico, P.; Young, M. H.; Tyler, S. W.

    2008-12-01

    The rhizosphere, a thin layer of soil (0 to 2 mm) surrounding a living root, is an important interface between bulk soil and plant root and plays a critical role in root water and nutrient uptake. In this study, we used X-ray Computerized Microtomography (microCT) to visualize soil structure around living roots non-destructively and with high spatial resolution. Four different plant species (Helianthus annuus, Lupinus hartwegii, Vigna radiata and Phaseolus lunatus), grown in four different porous materials (glass beads, medium and coarse sand, loam aggregates), were scanned with 10 ìm spatial resolution, using the microtomography beamline 8.3.2 at the Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA. Sample cross section images clearly show contacts between roots and soil particles, connecting water films, air-water interfaces as well as some cellular features of the plants taproots. We found with a simulation experiment, inflating a cylindrical micro-balloon in a pack of air-dry loam aggregates, that soil fracturing rather than compaction might occur around a taproot growing in dry soil. Form these preliminary experiments, we concluded that microCT has potential as a tool for a more process-based understanding of the role of rhizosphere soil structure on soil fertility, plant growth and the water balance at the earth-atmosphere interface.

  7. Evolution of Root Characters of Soybean Varieties Developed in Different Years

    Institute of Scientific and Technical Information of China (English)

    YANG Xiu-hong; WU Zong-pu; ZHANG Guo-dong

    2002-01-01

    It was studied that the evolution of root characteristics among 42 soybean varieties developed in Heilongjiang and Jilin Province in different years. The results showed that there were differences on the root characteristics among soybean varieties. From 1950s to 1990s, root fresh weight, root volume, root surface, root dry weight, lateral root length of main root characters tendedly increased with the variable development years. The root system of the varieties in 1990s was relatively well developed compared with that in the other years. The evolutionary trend of the root system of soybean varieties was increasing in root weight, root volume, root surface and length of lateral root.

  8. Differences in U root-to-shoot translocation between plant species explained by U distribution in roots.

    Science.gov (United States)

    Straczek, Anne; Duquene, Lise; Wegrzynek, Dariusz; Chinea-Cano, Ernesto; Wannijn, Jean; Navez, Jacques; Vandenhove, Hildegarde

    2010-03-01

    Accumulation and distribution of uranium in roots and shoots of four plants species differing in their cation exchange capacity of roots (CECR) was investigated. After exposure in hydroponics for seven days to 100 micromol U L(-1), distribution of uranium in roots was investigated through chemical extraction of roots. Higher U concentrations were measured in roots of dicots which showed a higher CECR than monocot species. Chemical extractions indicated that uranium is mostly located in the apoplasm of roots of monocots but that it is predominantly located in the symplasm of roots of dicots. Translocation of U to shoot was not significantly affected by the CECR or distribution of U between symplasm and apoplasm. Distribution of uranium in roots was investigated through chemical extraction of roots for all species. Additionally, longitudinal and radial distribution of U in roots of maize and Indian mustard, respectively showing the lowest and the highest translocation, was studied following X-ray fluorescence (XRF) analysis of specific root sections. Chemical analysis and XRF analysis of roots of maize and Indian mustard clearly indicated a higher longitudinal and radial transport of uranium in roots of Indian mustard than in roots of maize, where uranium mostly accumulated in root tips. These results showed that even if CECR could partly explain U accumulation in roots, other mechanisms like radial and longitudinal transport are implied in the translocation of U to the shoot. PMID:20080323

  9. Partical replacement of the rooting procedure of Chrysanthenum merifolium cuttings by pre-rooting storage in the dark.

    OpenAIRE

    Pol, van der, J.P.

    1988-01-01

    Part of the rooting procedure of Chrysanthemum morifolium 'Pink Boston' and 'Refour' cuttings can be replaced by pre-rooting storage in the dark. Pre-rooting storage of 7 days at temperatures between 9° and 21°C was adequate. Longer periods of dark storage resulted in increase of root growth but also in severe senescence of the basal leaves.

  10. Root-soil air gap and resistance to water flow at the soil-root interface of Robinia pseudoacacia.

    Science.gov (United States)

    Liu, X P; Zhang, W J; Wang, X Y; Cai, Y J; Chang, J G

    2015-12-01

    During periods of water deficit, growing roots may shrink, retaining only partial contact with the soil. In this study, known mathematical models were used to calculate the root-soil air gap and water flow resistance at the soil-root interface, respectively, of Robinia pseudoacacia L. under different water conditions. Using a digital camera, the root-soil air gap of R. pseudoacacia was investigated in a root growth chamber; this root-soil air gap and the model-inferred water flow resistance at the soil-root interface were compared with predictions based on a separate outdoor experiment. The results indicated progressively greater root shrinkage and loss of root-soil contact with decreasing soil water potential. The average widths of the root-soil air gap for R. pseudoacacia in open fields and in the root growth chamber were 0.24 and 0.39 mm, respectively. The resistance to water flow at the soil-root interface in both environments increased with decreasing soil water potential. Stepwise regression analysis demonstrated that soil water potential and soil temperature were the best predictors of variation in the root-soil air gap. A combination of soil water potential, soil temperature, root-air water potential difference and soil-root water potential difference best predicted the resistance to water flow at the soil-root interface.

  11. Methods for increasing the accuracy of approximate formulas for the roots of a cubic equation with complex conjugate roots

    International Nuclear Information System (INIS)

    Approximate formulas for determining the frequency and Q-factor of the complex conjugate roots, as well as the frequency of the real root, of the cubic equation for the case where the frequency of the complex-conjugate roots is close to the frequency of the real root have been presented in this work

  12. Differences in U root-to-shoot translocation between plant species explained by U distribution in roots

    Energy Technology Data Exchange (ETDEWEB)

    Straczek, Anne; Duquene, Lise [Belgium Nuclear Research Centre (SCK.CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium); Wegrzynek, Dariusz [IAEA, Seibersdorf Laboratories, A-2444 Seibersdorf (Austria); Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow (Poland); Chinea-Cano, Ernesto [IAEA, Seibersdorf Laboratories, A-2444 Seibersdorf (Austria); Wannijn, Jean [Belgium Nuclear Research Centre (SCK.CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium); Navez, Jacques [Royal Museum of Africa, Department of Geology, Leuvensesteenweg 13, 3080 Tervuren (Belgium); Vandenhove, Hildegarde, E-mail: hvandenh@sckcen.b [Belgium Nuclear Research Centre (SCK.CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium)

    2010-03-15

    Accumulation and distribution of uranium in roots and shoots of four plants species differing in their cation exchange capacity of roots (CECR) was investigated. After exposure in hydroponics for seven days to 100 mumol U L{sup -1}, distribution of uranium in roots was investigated through chemical extraction of roots. Higher U concentrations were measured in roots of dicots which showed a higher CECR than monocot species. Chemical extractions indicated that uranium is mostly located in the apoplasm of roots of monocots but that it is predominantly located in the symplasm of roots of dicots. Translocation of U to shoot was not significantly affected by the CECR or distribution of U between symplasm and apoplasm. Distribution of uranium in roots was investigated through chemical extraction of roots for all species. Additionally, longitudinal and radial distribution of U in roots of maize and Indian mustard, respectively showing the lowest and the highest translocation, was studied following X-ray fluorescence (XRF) analysis of specific root sections. Chemical analysis and XRF analysis of roots of maize and Indian mustard clearly indicated a higher longitudinal and radial transport of uranium in roots of Indian mustard than in roots of maize, where uranium mostly accumulated in root tips. These results showed that even if CECR could partly explain U accumulation in roots, other mechanisms like radial and longitudinal transport are implied in the translocation of U to the shoot.

  13. Modulation of root branching by a coumarin derivative

    OpenAIRE

    Li, Xiang; Gao, Ming-Jun

    2011-01-01

    A healthy root system is crucial to plant growth and survival. To maintain efficiency of root function, plants have to dynamically modulate root system architecture through various adaptive mechanisms such as lateral root formation to respond to a changing and diversified soil environment. Exogenous application of a coumarin derivative, 4-methylumbelliferone (4-MU), in Arabidopsis thaliana inhibits seed germination by mainly reducing primary root growth. UDP-glycosyltransferases play an integ...

  14. On Generalized m-th Root Finsler Metrics

    OpenAIRE

    Tayebi, A.; Peyghan, E.; M. Shahbazi

    2013-01-01

    In this paper, we characterize locally dually flat generalized m-th root Finsler metrics. Then we find a condition under which a generalized m-th root metric is projectively related to a m-th root metric. Finally, we prove that if a generalized m-th root metric is conformal to a m-th root metric, then both of them reduce to Riemannian metrics.

  15. Development of root observation method by image analysis system

    OpenAIRE

    Kim, Giyoung

    1995-01-01

    Knowledge of plant roots is important for determining plant-soil relationships, managing soil effectively, studying nutrient and water extraction, and creating a soil quality index. Plant root research is limited by the large amount of time and labor required to wash the roots from the soil and measure the viable roots. A root measurement method based on image analysis was proposed to reduce the time and labor requirement. A thinning algorithm-based image analysis method was us...

  16. Interactions between root canal irrigants, sealers and dentin

    OpenAIRE

    Neelakantan, P.

    2016-01-01

    The objective of this thesis was to determine the interactions between root filling materials and root dentin and to investigate if root canal irrigating solutions had an impact on these interactions. The following outcomes were assessed in the studies encompassed in this thesis: (i) dislocation resistance of an epoxy resin based root canal sealer and tricalcium silicate based root canal sealers, (ii) the influence of irrigation protocols on the sealing ability and chemical interactions with ...

  17. A NOTE ON THE STOCHASTIC ROOTS OF STOCHASTIC MATRICES

    Institute of Scientific and Technical Information of China (English)

    Qi-Ming HE; Eldon GUNN

    2003-01-01

    In this paper, we study the stochastic root matrices of stochastic matrices. All stochastic roots of 2×2 stochastic matrices are found explicitly. A method based on characteristic polynomial of matrix is developed to find all real root matrices that are functions of the original 3×3 matrix, including all possible (function) stochastic root matrices. In addition, we comment on some numerical methods for computing stochastic root matrices of stochastic matrices.

  18. Root tip-dependent, active riboflavin secretion by Hyoscyamus albus hairy roots under iron deficiency.

    Science.gov (United States)

    Higa, Ataru; Miyamoto, Erika; ur Rahman, Laiq; Kitamura, Yoshie

    2008-04-01

    Hyoscyamus albus hairy roots with/without an exogenous gene (11 clones) were established by inoculation of Agrobacterium rhizogenes. All clones cultured under iron-deficient condition secreted riboflavin from the root tips into the culture medium and the productivity depended on the number and size of root tips among the clones. A decline of pH was observed before riboflavin production and root development. By studying effects of proton-pump inhibitors, medium acidification with external organic acid, and riboflavin addition upon pH change and riboflavin productivity, we indicate that riboflavin efflux is not directly connected to active pH reduction, and more significantly active riboflavin secretion occurs as a response to an internal requirement in H. albus hairy roots under iron deficiency. PMID:18367404

  19. The role of root hairs in cadmium acquisition by barley

    Energy Technology Data Exchange (ETDEWEB)

    Zheng Ruilun; Li Huafen [Key Laboratory of Plant-Soil Interactions of the Ministry of Education, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100094 (China); Jiang Rongfeng, E-mail: rfjiang@cau.edu.c [Key Laboratory of Plant-Soil Interactions of the Ministry of Education, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100094 (China); Roemheld, Volker [Institute of Plant Nutrition, University of Hohenheim, D-70593 Stuttgart (Germany); Zhang Fusuo [Key Laboratory of Plant-Soil Interactions of the Ministry of Education, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100094 (China); Zhao Fangjie [Soil Science Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom)

    2011-02-15

    The role of root hairs in Cd acquisition from soil was investigated in three pot experiments using a root hairless mutant (bald root barley, brb) and its wild-type (WT) cultivar of barley (Hordeum vulgare). brb had significantly lower concentrations and lower total amounts of Cd in shoots than WT. The Cd uptake efficiency based on total root length was 8-45% lower in brb than in WT. The difference between brb and WT increased with increasing extractable Cd in soil under the experimental conditions used. Additions of phosphate to soil decreased Cd extractability. Both soil and foliar additions of phosphate decreased root length, and root hair formation in WT. These effects resulted in decreased Cd uptake with increasing P supply. Cd uptake in WT correlated significantly with root length, root hair length and density, and soil extractable Cd. Root hairs contribute significantly to Cd uptake by barley. - Research highlights: The Cd uptake efficiency was significantly lower in brb than in WT. Additions of phosphate to soil decreased Cd extractability and Cd uptake. Both soil and foliar additions of phosphate decreased root length, and root hair formation in WT. Root hairs contribute significantly to Cd uptake by barley. - The Cd uptake efficiency based on total root length was 8-45% lower in a barley root hairless mutant than in its wild-type, indicating an important role of root hairs in Cd acquisition.

  20. Endodontic Microsurgical Treatment of a Three-rooted Mandibular First Molar with Separate Distolingual Root: Report of One Case.

    Science.gov (United States)

    Wang, Han Guo; Xu, Ning; Yu, Qing

    2016-01-01

    The separate distolingual (DL) roots of three-rooted mandibular first molars are thought to be too difficult for performing apical surgery. This article represents microsurgical treatment of a three-rooted mandibular first molar with a separate DL root. The procedure includes incision and flap retraction, osteotomy, apicoectomy, retropreparation and retrofilling of the root canal, using micro instruments, ultrasonic retrotips and mineral trioxide aggregate (MTA) under a dental operating microscope. Two mm in length of apical root resection, 2 mm in depth of root canal retropreparation with a personalised ultrasonic retrotip, and 2 mm in length of retrofilling with MTA are the key points for accomplishment of apical surgery on separate DL roots. The case was followed up for 15 months after surgery. Clinical and radiographic examinations revealed complete healing of periapical tissue. Separate DL roots of three-rooted mandibular first molars can be treated by endodontic microsurgery with modifications from standard protocol. PMID:27622221

  1. Effects of nutrition spatial heterogeneity on root traits and carbon usage by roots of Cercis chinensis seedlings in split root rooms

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In natural ecosystems, nutrition available for plants shows great spatial heterogeneity. Much is known about plant root responses to the spatial heterogeneity of nutrition, but little is known about carbon usage in roots in nutrition-deficient patches and its effect on root longevity. In this study, split-room boxes were used for culture of Cercis chinensis seedlings, and the small rooms were supplied with different nutrition levels. The number of the first-order roots in the rooms with nutrition supply was significantly higher than that in the rooms with deficient nutrition. Specific root length (SRL) of the first-order roots in the rooms with deficient nutrition reached its peak at day 64 after nutrition treatment. There was no significant SRL differences between the two order roots during the experiment. Biomass of the first-order roots in the rooms without nutrition supply was significantly less than that of the first-order roots in the rooms with nutrition supply from day 64 to 96. The total biomass of the lateral roots in the rooms without nu-trition supply decreased from day 64 to 96. The activities of the enzymes in roots in the rooms without nutrition supply increased and the activities of alkaline invertases in roots in the two sides of split box did not change significantly. The activities of the enzymes in roots in the rooms without nutrition supply increased gradually. These results suggest that nutrition spatial heterogeneity induced the changes in root traits and plants actively controlled carbon usage in roots in nutrition-deficient patches by regulating the activities of invertases and sucrose synthases, resulting in the reduction in carbon usage in the roots in nutrition-deficient patches.

  2. RootAnalyzer: A Cross-Section Image Analysis Tool for Automated Characterization of Root Cells and Tissues

    OpenAIRE

    Joshua Chopin; Hamid Laga; Chun Yuan Huang; Sigrid Heuer; Miklavcic, Stanley J.

    2015-01-01

    The morphology of plant root anatomical features is a key factor in effective water and nutrient uptake. Existing techniques for phenotyping root anatomical traits are often based on manual or semi-automatic segmentation and annotation of microscopic images of root cross sections. In this article, we propose a fully automated tool, hereinafter referred to as RootAnalyzer, for efficiently extracting and analyzing anatomical traits from root-cross section images. Using a range of image processi...

  3. Unleashing the potential of the root hair cell as a single plant cell type model in root systems biology

    OpenAIRE

    Zhenzhen eQiao; Marc eLibault

    2013-01-01

    Plant root is an organ composed of multiple cell types with different functions. This multicellular complexity limits our understanding of root biology because –omics studies performed at the level of the entire root reflect the average responses of all cells composing the organ. To overcome this difficulty and allow a more comprehensive understanding of root cell biology, an approach is needed that would focus on one single cell type in the plant root. Because of its biological functions (i....

  4. Amyloplast Sedimentation Kinetics in Corn Roots

    Science.gov (United States)

    Leopold, A. C.; Sack, F.

    1985-01-01

    Knowledge of the parameters of amyloplast sedimentation is crucial for an evaluation of proposed mechanisms of root graviperception. Early estimates of the rate of root amyloplast sedimentation were as low as 1.2 micron/min which may be too slow for many amyloplasts to reach the vicinity of the new lower wall within the presentation time. On this basis, Haberlandt's classical statolith hypothesis involving amyloplast stimulation of a sensitive surface near the new lower wall was questioned. The aim was to determine the kinetics of amyloplast sedimentation with reference to the presentation time in living and fixed corn rootcap cells as compared with coleoptiles of the same variety.

  5. Unit root behavior in energy futures prices

    OpenAIRE

    Serletis, Apostolos

    1992-01-01

    This paper re-examines the empirical evidence for random walk type behavior in energy futures prices. In doing so, tests for unit roots in the univariate time-series representation of the daily crude oil, heating oil, and unleaded gasoline series are performed using recent state-of-the-art methodology. The results show that the unit root hypothesis can be rejected if allowance is made for the possibility of a one-time break in the intercept and the slope of the trend function at an unknown po...

  6. Root approach for estimation of statistical distributions

    Science.gov (United States)

    Bogdanov, Yu. I.; Bogdanova, N. A.

    2014-12-01

    Application of root density estimator to problems of statistical data analysis is demonstrated. Four sets of basis functions based on Chebyshev-Hermite, Laguerre, Kravchuk and Charlier polynomials are considered. The sets may be used for numerical analysis in problems of reconstructing statistical distributions by experimental data. Based on the root approach to reconstruction of statistical distributions and quantum states, we study a family of statistical distributions in which the probability density is the product of a Gaussian distribution and an even-degree polynomial. Examples of numerical modeling are given.

  7. Root approach for estimation of statistical distributions

    CERN Document Server

    Bogdanov, Yu I

    2014-01-01

    Application of root density estimator to problems of statistical data analysis is demonstrated. Four sets of basis functions based on Chebyshev-Hermite, Laguerre, Kravchuk and Charlier polynomials are considered. The sets may be used for numerical analysis in problems of reconstructing statistical distributions by experimental data. Based on the root approach to reconstruction of statistical distributions and quantum states, we study a family of statistical distributions in which the probability density is the product of a Gaussian distribution and an even-degree polynomial. Examples of numerical modeling are given. The results of present paper are of interest for the development of tomography of quantum states and processes.

  8. Why Frequency Matters for Unit Root Testing

    OpenAIRE

    Boswijk, H.P.; Klaassen, F.J.G.M.

    2005-01-01

    It is generally believed that for the power of unit root tests, only the time span and not the observation frequency matters. In this paper we show that the observation frequency does matter when the high-frequency data display fat tails and volatility clustering, as is typically the case for financial time series such as exchange rate returns. Our claim builds on recent work on unit root and cointegration testing based non-Gaussian likelihood functions. The essential idea is that such method...

  9. Isolated root caps, border cells, and mucilage from host roots stimulate hyphal branching of the arbuscular mycorrhizal fungus, Gigaspora gigantea.

    Science.gov (United States)

    Nagahashi, Gerald; Douds, David D

    2004-09-01

    Unlike previous reports that have shown that water soluble and volatile compounds from roots or root exudates play an important role in precolonization events during arbuscular mycorrhizal (AM) fungus-host root interactions (Bécard & Piché 1989, Giovannetti et al. 1993), the results shown here deal with particulate and viscous fractions isolated from host roots. Root caps and a slow sedimenting particulate fraction (SSPF) were rapidly isolated and separated from Ri T-DNA transformed carrot roots (D. carota) grown in liquid culture. In addition, border cells (BC) and mucilage were isolated from aseptically grown corn seedlings (Zea mays). Root caps, SSPF (composed mainly of small root cap fragments and some BCs), BCs, and mucilage all had an associated AM fungus hyphal branching stimulator. Root caps stored for 5 d at 4 degrees C appeared to either synthesize or slowly release the branching stimulator. Also, isolated root caps from roots grown in the absence of P contained more branch stimulating activity than those isolated from roots grown in the presence of P. Although the branching stimulation activity in particulate fractions was low compared to that of the exudate, the particulate fractions can stick to the root surface at considerable distances from the root tip. This may be significant during the infection and colonization of host roots at sites far removed from the primary location of exudation.

  10. QTL Information Table: 121 [Q-TARO

    Lifescience Database Archive (English)

    Full Text Available Morphological trait Root adventitious root number(flooding) Mixture C)Interval DHL ...ndidate genes for rice root growth under flooding and upland conditions. Yi Chuan Xue Bao 33, 141-151. ...

  11. ROOT.NET: Using ROOT from .NET languages like C and F

    International Nuclear Information System (INIS)

    ROOT.NET provides an interface between Microsoft's Common Language Runtime (CLR) and .NET technology and the ubiquitous particle physics analysis tool, ROOT. ROOT.NET automatically generates a series of efficient wrappers around the ROOT API. Unlike pyROOT, these wrappers are statically typed and so are highly efficient as compared to the Python wrappers. The connection to .NET means that one gains access to the full series of languages developed for the CLR including functional languages like F (based on OCaml). Many features that make ROOT objects work well in the .NET world are added (properties, IEnumerable interface, LINQ compatibility, etc.). Dynamic languages based on the CLR can be used as well, of course (Python, for example). Additionally it is now possible to access ROOT objects that are unknown to the translation tool. This poster will describe the techniques used to effect this translation, along with performance comparisons, and examples. All described source code is posted on the open source site CodePlex.

  12. Tissue specific localization of root infection by fungal pathogens: role of root border cells.

    Science.gov (United States)

    Gunawardena, Uvini; Hawes, Martha C

    2002-11-01

    When roots of pea seedlings were inoculated uniformly with spores of Nectria haematocca or other pea pathogenic fungi, more than 90% developed lesions in the region of elongation within 3 days. More mature regions of most roots as well as the tip showed no visible signs of infection. Yet, microscopic observation revealed that 'mantles,' comprised of fungal hyphae intermeshed with populations of border cells, covered the tips of most roots. After physical detachment of the mantle, the underlying tip of most roots was found to be free of infection. Mantle-covered root tips did not respond to invasion of their border cells by activation of known defense genes unless there was invasion of the tip itself, as revealed by the presence of a lesion. Concomitant with the activation of defense genes was the induction of a cell-wall degrading enzyme whose expression is a marker for renewed production of border cells. Mantle formation did not occur in response to nonpathogens. The data are consistent with the hypothesis that border cells serve as a host-specific 'decoy' that protects root meristems by inhibiting fungal infection of the root tip.

  13. Arabidopsis alcohol dehydrogenase expression in both shoots and roots is conditioned by root growth environment

    Science.gov (United States)

    Chung, H. J.; Ferl, R. J.

    1999-01-01

    It is widely accepted that the Arabidopsis Adh (alcohol dehydrogenase) gene is constitutively expressed at low levels in the roots of young plants grown on agar media, and that the expression level is greatly induced by anoxic or hypoxic stresses. We questioned whether the agar medium itself created an anaerobic environment for the roots upon their growing into the gel. beta-Glucuronidase (GUS) expression driven by the Adh promoter was examined by growing transgenic Arabidopsis plants in different growing systems. Whereas roots grown on horizontal-positioned plates showed high Adh/GUS expression levels, roots from vertical-positioned plates had no Adh/GUS expression. Additional results indicate that growth on vertical plates closely mimics the Adh/GUS expression observed for soil-grown seedlings, and that growth on horizontal plates results in induction of high Adh/GUS expression that is consistent with hypoxic or anoxic conditions within the agar of the root zone. Adh/GUS expression in the shoot apex is also highly induced by root penetration of the agar medium. This induction of Adh/GUS in shoot apex and roots is due, at least in part, to mechanisms involving Ca2+ signal transduction.

  14. Root Traits and Phenotyping Strategies for Plant Improvement

    Directory of Open Access Journals (Sweden)

    Ana Paez-Garcia

    2015-06-01

    Full Text Available Roots are crucial for nutrient and water acquisition and can be targeted to enhance plant productivity under a broad range of growing conditions. A current challenge for plant breeding is the limited ability to phenotype and select for desirable root characteristics due to their underground location. Plant breeding efforts aimed at modifying root traits can result in novel, more stress-tolerant crops and increased yield by enhancing the capacity of the plant for soil exploration and, thus, water and nutrient acquisition. Available approaches for root phenotyping in laboratory, greenhouse and field encompass simple agar plates to labor-intensive root digging (i.e., shovelomics and soil boring methods, the construction of underground root observation stations and sophisticated computer-assisted root imaging. Here, we summarize root architectural traits relevant to crop productivity, survey root phenotyping strategies and describe their advantages, limitations and practical value for crop and forage breeding programs.

  15. [Morphology of wheat roots under low-phosphorus stress].

    Science.gov (United States)

    Sun, Haiguo; Zhang, Fusuo

    2002-03-01

    The morphology of root systems of different wheat (Triticum aestivum L.) genotypes under low-phosphorus stress were studied to determine the effects of external factors on components of root system and the early morphological indicators related to phosphorus efficiency. The number of root axes and the length of lateral root of P-deficient plant were significantly lower than those of P-sufficient plant. The length of root axis and root system, and the number of lateral roots were sharply increased under low-P stress. The number and length of root axis were significantly different under different levels of phosphorus supply and among different wheat genotypes under same phosphorus supply. This implied that the two traits (number and length of root axis) were controlled by genotype and external factors. The difference in the characteristics of lateral root of the given wheat genotypes was significant only between different levels of P supply. It showed that the traits of lateral root mainly depended on external factors. The length and number of root axis, root length, and root angle were significantly different among 6 wheat genotypes. There exited significant linear relationships between relative grain yield and the interaction of the morphological traits, and it implied that the traits could be used as early indicators of selecting high P-efficiency wheat varieties.

  16. Mycorrhiza alters the profile of root hairs in trifoliate orange.

    Science.gov (United States)

    Wu, Qiang-Sheng; Liu, Chun-Yan; Zhang, De-Jian; Zou, Ying-Ning; He, Xin-Hua; Wu, Qing-Hua

    2016-04-01

    Root hairs and arbuscular mycorrhiza (AM) coexist in root systems for nutrient and water absorption, but the relation between AM and root hairs is poorly known. A pot study was performed to evaluate the effects of four different AM fungi (AMF), namely, Claroideoglomus etunicatum, Diversispora versiformis, Funneliformis mosseae, and Rhizophagus intraradices on root hair development in trifoliate orange (Poncirus trifoliata) seedlings grown in sand. Mycorrhizal seedlings showed significantly higher root hair density than non-mycorrhizal seedlings, irrespective of AMF species. AMF inoculation generally significantly decreased root hair length in the first- and second-order lateral roots but increased it in the third- and fourth-order lateral roots. AMF colonization induced diverse responses in root hair diameter of different order lateral roots. Considerably greater concentrations of phosphorus (P), nitric oxide (NO), glucose, sucrose, indole-3-acetic acid (IAA), and methyl jasmonate (MeJA) were found in roots of AM seedlings than in non-AM seedlings. Levels of P, NO, carbohydrates, IAA, and MeJA in roots were correlated with AM formation and root hair development. These results suggest that AMF could alter the profile of root hairs in trifoliate orange through modulation of physiological activities. F. mosseae, which had the greatest positive effects, could represent an efficient AM fungus for increasing fruit yields or decreasing fertilizer inputs in citrus production.

  17. Adjustment of Forest Ecosystem Root Respiration as Temperature Warms

    Institute of Scientific and Technical Information of China (English)

    Andrew J. Burton; Jerry M. Melillo; Serita D. Frey

    2008-01-01

    Adjustment of ecosystem root respiration to warmer climatic conditions can alter the autotrophic portion of soil respiration and influence the amount of carbon available for biomass production. We examined 44 published values of annual forest root respiration and found an increase in ecosystem root respiration with increasing mean annual temperature (MAT),but the rate of this cross-ecosystem increase (Q10 = 1.6) is less than published values for short-term responses of root respiration to temperature within ecosystems (Q10 = 2-3). When specific root respiration rates and root biomass values were examined, there was a clear trend for decreasing root metabolic capacity (respiration rate at a standard temperature) with increasing MAT. There also were tradeoffs between root metabolic capacity and root system biomass, such that there were no instances of high growing season respiration rates and high root biomass occurring together. We also examined specific root respiration rates at three soil warming experiments at Harvard Forest, USA, and found decreases in metabolic capacity for roots from the heated plots. This decline could be due to either physiological acclimation or to the effects of co-occurring drier soils on the measurement date. Regardless of the cause, these findings clearly suggest that modeling efforts that allow root respiration to increase exponentially with temperature, with Qt0 values of 2 or more, may over-predict root contributions to ecosystem CO2 efflux for future climates and underestimate the amount of C available for other uses,including net primary productivity.

  18. Rooting greenwood tip cuttings of several Populus clones hydroponically (hydroponic rooting of Populus cuttings)

    Energy Technology Data Exchange (ETDEWEB)

    Phipps, H.M.; Hansen, E.A.; Tolsted, D.N.

    1980-01-01

    Greenwood cuttings of several Populus clones were successfully rooted with a relatively simple hydroponic method. Indolebutyric acid and naphthaleneacetic acid at concentrations of 500 to 5000 ppM applied as a quick dip to the cutting bases, a complete nutrient solution at 20 to 40% of full strength, and a solution temperature between 27 and 30/sup 0/C generally produced the best rooting performance of most clones. Cuttings propagated by the hydroponic procedure rooted faster and generally outgrew those produced by a standard method after being transplanted to pots and grown in the greenhouse.

  19. Avaliação da porosidade e placa férrica de raízes de arroz cultivado em hipoxia Evaluation of porosity and iron plaque on rice roots grown under hypoxia

    Directory of Open Access Journals (Sweden)

    Marquel Jonas Holzschuh

    2010-10-01

    servir como estimativa da formação de aerênquima no arroz. O método de obtenção de raízes foi eficiente em promover a eliminação de O2 do saco de vinil para estudar a formação do aerênquima.The high oxygen diffusion in different materials makes the establishment and maintenance of oxygen-free environments difficult. The techniques used to obtain oxygen-free environments are little efficient and not representative of flooded soil conditions. The purpose of this study was to develop a method for obtaining roots in a hypoxic environment to evaluate iron plaque and aerenchyma formation in rice plants. A hypoxic condition similar to that of flooded soils was created in 50 L tanks, based on the oxygen diffusion capacity through vinyl plastic in contact with flooded soil. Each tank was filled with soil (Gley soil, five vinyl bags and then flooded. Rice plants of the genotypes IRGA 423 and IRGA 424 grown in the field were collected, the roots cut at the stem, washed and 1/3 of the leaves removed. Each bag was filled with 12 plants of each genotype and nutrient solution. After seven days, the new adventitious roots were used to determine the iron plaque and aerenchyma formation in the segments 0-2, 2-4 and 4-6 cm from the root tips. The roots were exposed the solution of a flooded soil for 4 hours. The iron plaque was determined in the root segments after iron extraction with HCl 0.5 mol L-1. Porosity was determined in vacuum cycles applied with a syringe. The weight difference before and after vacuum treatment and water entrance was assumed as estimate of the magnitude of the aerenchyma of the roots. The method was tested with the production of new adventitious roots in vinyl bags under aerated and hypoxic conditions. Root porosity was higher in the hypoxic than in the aerated environment. Porosity was higher near plant base and as porosity increased, iron increased near the root surface, indicating the iron plaque as a parameter to estimate aerenchyma formation in

  20. An antileishmanial chalcone from Chinese licorice roots

    DEFF Research Database (Denmark)

    Christensen, S B; Ming, C; Andersen, L;

    1994-01-01

    A bioassay guided fractionation of an extract of Chinese licorice roots led to the isolation of (E)-1-[2,4-dihydroxy-3-(3-methyl-2-butenyl)phenyl]-3-[4- hydroxy-3-(3-methyl-2-butenyl]phenyl-2-propen-1-one, which in vitro showed potent antileishmanial activity. In addition, the novel chalcone (E)-1...