Cerium enhances germination and shoot growth, and alters mineral nutrient concentration in rice

Science.gov (United States)

García-Morales, Soledad; Pérez-Sato, Juan Antonio

2018-01-01

Cerium (Ce) belongs to the rare earth elements (REEs), and although it is not essential for plants, it can stimulate growth and other physiological processes. The objective of this research was to evaluate the effect of Ce on seed germination, initial seedling growth, and vegetative growth in rice (Oryza sativa L.) cv. Morelos A-98. During the germination process, the seeds were treated with Ce concentrations of 0, 4, 8, and 12 μM; after 5 d, germination percentage was recorded and after 10 d seedling growth was measured. For vegetative growth, a hydroponic system was established where 14-d-old plants without previous Ce treatment were transferred into nutrient solution. After two weeks of acclimatizing, 0, 25, 50, and 100 μM Ce were added to the nutrient solution for 28 d. Ce significantly increased germination and the initial growth variables of the seedlings. During vegetative growth, Ce increased plant height, number of tillers, root volume, and shoot fresh and dry biomass, without affecting root biomass weight. With low Ce concentrations (25 and 50 μM), the concentrations of chlorophylls and amino acids in the shoots were similar to those in the control, like amino acid concentration in the roots at a concentration of 25 μM Ce. Conversely, the concentration of total sugars increased in the shoot with the application of 25, 50, and 100 μM Ce, and in the roots with the application of 50 μM Ce. Also, Ce did not affect the concentration of macro or micronutrients in the shoots. However, in the roots, the high Ce concentration decreased the concentrations of Ca, Fe, Mn, and Zn, while the Mg concentration increased. Our results indicate that Ce, at the right concentrations, can function as a biostimulant in rice germination and growth. PMID:29579100

Effects of plant growth regulators on callus, shoot and root formation ...

African Journals Online (AJOL)

Root and stem explants of fluted pumpkin were cultured in medium containing different types and concentrations of plant growth regulators (PGRs). The explants were observed for callus, root and shoot formation parameters after four months. Differences among explants, plant growth regulators and their interaction were ...

Growth and artemisinin content of artemisia Annua L. As a result of gamma irradiation on shoot culture

International Nuclear Information System (INIS)

Tri Muji Ermayanti; Erwin Al Hafiizh; Andri Fadillah Martin; Arthur A Lelono; Wiguna Rahman

2016-01-01

Artemisinin is the main compound produced by Artemisia annua is used as antimalarial drug. Many research have been conducted in order to increase artemisinin content in A. annua so that it can be produced economically. In several plants, mutation can be induced by Gamma irradiation to increase their secondary metabolite production. The aim of this research was to investigate the growth and artemisinin content of A. annua after Gamma irradiation. Irradiation was conducted using in vitro shoot tips with 5-50 Gy. Survival rate, growth of shoot culture, ploidy level confirmation, acclimatization, growth of plants in the field and artemisinin content were recorded. The results showed that LD_5_0 of A. annua was 37 Gy, therefore, shoots only grew in the control environment in the laboratory, their growth in the field was inhibited. Irradiation with 50 Gy, shoots only grew for 8 weeks, and died afterwards. Irradiation dose affected on growth of plants in the field as well as their artemisinin content. (author)

Growth of and partitioning between shoot and storage root of carrot in a northern climate

Directory of Open Access Journals (Sweden)

T. SUOJALA

2008-12-01

Full Text Available Matching the growth pattern of a vegetable cultivar with the seasonal changes in climate is a prerequisite for successful yield production in a northern climate. This paper describes the growth characteristics of two carrot cultivars in relation to climatic conditions in two years, with special reference to the factors associated with high yield. Cv. Fontana produced twice as large a leaf area and shoot weight as cv. Panther. Increased partitioning to shoot in the former cultivar also resulted in a higher root yield. Uniformity in relative growth rates during the period of analysis suggests that intervarietal differences in the shoot to root ratio and in the yield potential appear very early. Nearly half of the root weight at final harvest was gained after mid-August, when temperature and daily irradiance began to decrease. A large leaf area may ensure better utilisation of diminishing growth resources at the end of the growing season. In the more favourable growing season, 1997, plants invested more in leaf production than they did in 1996: shoot fresh and dry weights were considerably higher but leaf area was not much higher.;

Influence of plant maturity, shoot reproduction and sex on vegetative growth in the dioecious plant Urtica dioica.

Science.gov (United States)

Oñate, Marta; Munné-Bosch, Sergi

2009-10-01

Stinging nettle (Urtica dioica) is a herbaceous, dioecious perennial that is widely distributed around the world, reproduces both sexually and asexually, and is characterized by rapid growth. This work was aimed at evaluating the effects of plant maturity, shoot reproduction and sex on the growth of leaves and shoots. Growth rates of apical shoots, together with foliar levels of phytohormones (cytokinins, auxins, absicisic acid, jasmonic acid and salicylic acid) and other indicators of leaf physiology (water contents, photosynthetic pigments, alpha-tocopherol and F(v)/F(m) ratios) were measured in juvenile and mature plants, with a distinction made between reproductive and non-reproductive shoots in both males and females. Vegetative growth rates were not only evaluated in field-grown plants, but also in cuttings obtained from these plants. All measurements were performed during an active vegetative growth phase in autumn, a few months after mature plants reproduced during spring and summer. Vegetative growth rates in mature plants were drastically reduced compared with juvenile ones (48 % and 78 % for number of leaves and leaf biomass produced per day, respectively), which was associated with a loss of photosynthetic pigments (up to 24 % and 48 % for chlorophylls and carotenoids, respectively) and increases of alpha-tocopherol (up to 2.7-fold), while endogenous levels of phytohormones did not differ between mature and juvenile plants. Reductions in vegetative growth were particularly evident in reproductive shoots of mature plants, and occurred similarly in both males and females. It is concluded that (a) plant maturity reduces vegetative growth in U. dioica, (b) effects of plant maturity are evident both in reproductive and non-reproductive shoots, but particularly in the former, and (c) these changes occur similarly in both male and female plants.

Preformation in vegetative buds of pistachio (Pistacia vera): relationship to shoot morphology, crown structure and rootstock vigor.

Science.gov (United States)

Spann, Timothy M; Beede, Robert H; Dejong, Theodore M

2007-08-01

Effects of rootstock, shoot carbohydrate status, crop load and crown position on the number of preformed leaf primordia in the dormant terminal and lateral buds of mature and immature 'Kerman' pistachio (Pistacia vera L.) trees were investigated to determine if rootstock vigor is associated with greater shoot preformation. There was no significant variation in preformation related to the factors studied, suggesting strong genetic control of preformation in 'Kerman' pistachio. The growth differences observed among trees on different rootstocks were associated with greater stimulation of neoformed growth in trees on the more vigorous rootstocks. However, most annual extension growth in mature tree crowns was preformed, contrasting with the relatively high rate of neoformation found in young tree crowns. Large amounts of neoformed growth in young trees may allow the trees to become established quickly and secure resources, whereas predominantly preformed growth in mature trees may allow for continued crown expansion without outgrowing available resources. We hypothesized that the stimulation of neoformed growth by the more vigorous rootstocks is associated with greater resource uptake or transport, or both. Understanding the source of variation in shoot extension growth on different rootstocks has important implications for orchard management practices.

Multiple shoot cultures of Atropa belladonna: Effect of physico-chemical factors on growth and alkaloid formation

International Nuclear Information System (INIS)

Benjamin, B.D.; Roja, P.C.; Heble, M.R.; Chandha, M.S.

1987-01-01

Multiple shoot cultures were established from shoot tip and axillary meristem of the plant Atropa belladonna. The cultures were initially raised on agar medium and subsequently maintained on liquid medium of Murashige and Skoog (1962) supplemented with BA. These cultures were subjected to different doses of -y-irradiation. Recovery from the radiation effects was observed in tissues subjected to 29 Gy during four successive passages. Plant growth regulators influenced the growth and morphogenetic events of the tissues. The precursors of tropane alkaloids marginally increased the alkaloid synthesis during the stationary phase of growth. Shoot cultures, established from different field grown plants varying in alkaloid content, were morphologically similar and did not exhibit the parental characteristics with respect to alkaloid formation

Photoperiod and growth regulators on in vitro shoot induction in Heliconia latispatha

Directory of Open Access Journals (Sweden)

Antonio Anderson de Jesus Rodrigues

2016-12-01

Full Text Available Considering the growing economic importance of tropical flowers and the advantages of techniques applied to the in vitro cultivation of these plants, it is necessary to carry out studies to evaluate growth in species such as Heliconia latispatha. The aim of this study therefore, was to evaluate in vitro shoot induction for different concentrations of BAP and NAA and as a function of the photoperiod. Explants from zygotic embryos were inoculated in MS medium containing different concentrations of BAP (0.0, 0.5, 1.0, 1.5, 2.0 or 2.5 mg L-1, with the cultures kept in a growth room at a temperature of 24.0 ± 2.0° C, under a photoperiod of 12 and 16 hours of light and a light intensity of 30 μmol m-2 s-1. At 21, 28, 35, 42 and 49 days after inoculation, the number of shoots per explant was evaluated. The treatment at the BAP concentration that gave the best multiplication rate (2.5 mg L-1 was set, and was tested in a further trial with different concentrations of NAA (0.0, 0.2, 0.4, 0 6, 0.8 or 1.0 mg L-1 under the same conditions as the previous experiment. The experimental designs were completely randomised, with five replications, and analysed in a 6 x 2 factorial. The data were submitted to analysis of variance and regression. No significant differences were seen in relation to the photoperiod or its interaction with the cytokinin and auxin under test. Multiplication was greater in the presence of 2.5 mg L-1 BAP, which gave a rate of 1.25 shoots/explant at 49 days of in vitro culture. The association of this BAP dosage with 1.0 mg L-1 NAA was even more efficient, producing 1.83 shoots per explant at 30 days of growth. The use of BAP together with NAA is beneficial to the induction of shoots in H. latispatha.

Nutrient and mineral composition during shoot growth in seven species of Phyllostachys and Pseudosasa bamboo consumed by giant panda.

Science.gov (United States)

Christian, A L; Knott, K K; Vance, C K; Falcone, J F; Bauer, L L; Fahey, G C; Willard, S; Kouba, A J

2015-12-01

During the annual period of bamboo shoot growth in spring, free-ranging giant pandas feed almost exclusively on the shoots while ignoring the leaves and full- height culm. Little is known about the nutritional changes that occur during bamboo shoot growth, if nutritional changes differ among species, or how these changes might influence forage selection. Our objective was to examine the nutrient and mineral composition during three phases of shoot growth (180 cm) for seven species of bamboo (Phyllostachys (P.) aurea, P. aureosulcata, P. bissetii, P. glauca, P. nuda, P. rubromarginata, Pseudosasa japonica) fed to captive giant pandas at the Memphis Zoo. Total dietary fiber content of bamboo shoots increased (p 180 cm, while crude protein, fat and ash exhibited significant declines (p panda diets when available. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

Genetic relationship between plant growth, shoot and kernel sizes in ...

African Journals Online (AJOL)

Maize (Zea mays L.) ear vascular tissue transports nutrients that contribute to grain yield. To assess kernel heritabilities that govern ear development and plant growth, field studies were conducted to determine the combining abilities of parents that differed for kernel-size, grain-filling rates and shoot-size. Thirty two hybrids ...

Evolutionary potential of root chemical defense: genetic correlations with shoot chemistry and plant growth.

Science.gov (United States)

Parker, J D; Salminen, J-P; Agrawal, Anurag A

2012-08-01

Root herbivores can affect plant fitness, and roots often contain the same secondary metabolites that act as defenses in shoots, but the ecology and evolution of root chemical defense have been little investigated. Here, we investigated genetic variance, heritability, and correlations among defensive phenolic compounds in shoot vs. root tissues of common evening primrose, Oenothera biennis. Across 20 genotypes, there were roughly similar concentrations of total phenolics in shoots vs. roots, but the allocation of particular phenolics to shoots vs. roots varied along a continuum of genotype growth rate. Slow-growing genotypes allocated 2-fold more of the potential pro-oxidant oenothein B to shoots than roots, whereas fast-growing genotypes had roughly equivalent above and belowground concentrations. Phenolic concentrations in both roots and shoots were strongly heritable, with mostly positive patterns of genetic covariation. Nonetheless, there was genotype-specific variation in the presence/absence of two major ellagitannins (oenothein A and its precursor oenothein B), indicating two different chemotypes based on alterations in this chemical pathway. Overall, the presence of strong genetic variation in root defenses suggests ample scope for the evolution of these compounds as defenses against root herbivores.

Branch architecture in Ginkgo biloba: wood anatomy and long shoot-short shoot interactions.

Science.gov (United States)

Little, Stefan A; Jacobs, Brooke; McKechnie, Steven J; Cooper, Ranessa L; Christianson, Michael L; Jernstedt, Judith A

2013-10-01

Ginkgo, centrally placed in seed plant phylogeny, is considered important in many phylogenetic and evolutionary studies. Shoot dimorphism of Ginkgo has been long noted, but no work has yet been done to evaluate the relationships between overall branch architecture and wood ring characters, shoot growth, and environmental conditions. • Branches, sampled from similar canopy heights, were mapped with the age of each long shoot segment determined by counting annual leaf-scar series on its short shoots. Transverse sections were made for each long shoot segment and an adjacent short shoot; wood ring thickness, number of rings, and number of tracheids/ring were determined. Using branch maps, we identified wood rings for each long shoot segment to year and developmental context of each year (distal short shoot growth only vs. at least one distal long shoot). Climate data were also analyzed in conjunction with developmental context. • Significantly thicker wood rings occur in years with distal long shoot development. The likelihood that a branch produced long shoots in a given year was lower with higher maximum annual temperature. Annual maximum temperature was negatively correlated with ring thickness in microsporangiate trees only. Annual minimum temperatures were correlated differently with ring thickness of megasporangiate and microsporangiate trees, depending on the developmental context. There were no significant effects associated with precipitation. • Overall, developmental context alone predicts wood ring thickness about as well as models that include temperature. This suggests that although climatic factors may be strongly correlated with wood ring data among many gymnosperm taxa, at least for Ginkgo, correlations with climate data are primarily due to changes in proportions of shoot developmental types (LS vs. SS) across branches.

The effect of sodium hypochlorite solutions on in vitro seedling growth and shoot regeneration of flax (Linum usitatissimum)

Science.gov (United States)

Yildiz, Mustafa; Er, Celâl

2002-04-01

The aim of this study was to determine the effect of concentration (40, 60, and 80%) and temperature (0, 10, 20, and 30°C) of sodium hypochlorite (NaOCl) solutions on seed germination, in vitro viability and growth of flax seedlings and regeneration capacity of hypocotyl explants. Results showed that seed germination, seedling growth and shoot regeneration were negatively affected by increasing concentration and temperature of disinfectant. The best results in seedling growth and shoot regeneration were obtained when 40% disinfectant concentration at 10°C was used.

Identification of water use strategies at early growth stages in durum wheat from shoot phenotyping and physiological measurements.

Directory of Open Access Journals (Sweden)

ALIREZA NAKHFOROOSH

2016-08-01

Full Text Available Modern imaging technology provides new approaches to plant phenotyping for traits relevant to crop yield and resource efficiency. Our objective was to investigate water use strategies at early growth stages in durum wheat genetic resources using shoot imaging at the ScreenHouse phenotyping facility combined with physiological measurements. 12 durum landraces from different pedoclimatic backgrounds were compared to three modern check cultivars in a greenhouse pot experiment under well watered (75 % plant available water, PAW and drought (25 % PAW conditions. Transpiration rate was analyzed for the underlying main morphological (leaf area duration and physiological (stomata conductance factors. Combining both morphological and physiological regulation of transpiration, four distinct water use types were identified. Most landraces had high transpiration rates either due to extensive leaf area (area types or both large leaf areas together with high stomata conductance (spender types. All modern cultivars were distinguished by high stomata conductance with comparatively compact canopies (conductance types. Only few landraces were water saver types with both small canopy and low stomata conductance. During early growth, genotypes with large leaf area had high dry-matter accumulation under both well watered and drought conditions compared to genotypes with compact stature. However, high stomata conductance was the basis to achieve high dry matter per unit leaf area, indicating high assimilation capacity as a key for productivity in modern cultivars. We conclude that the identified water use strategies based on early growth shoot phenotyping combined with stomata conductance provide an appropriate framework for targeted selection of distinct pre-breeding material adapted to different types of water limited environments.

Identification of Water Use Strategies at Early Growth Stages in Durum Wheat from Shoot Phenotyping and Physiological Measurements

Science.gov (United States)

Nakhforoosh, Alireza; Bodewein, Thomas; Fiorani, Fabio; Bodner, Gernot

2016-01-01

Modern imaging technology provides new approaches to plant phenotyping for traits relevant to crop yield and resource efficiency. Our objective was to investigate water use strategies at early growth stages in durum wheat genetic resources using shoot imaging at the ScreenHouse phenotyping facility combined with physiological measurements. Twelve durum landraces from different pedoclimatic backgrounds were compared to three modern check cultivars in a greenhouse pot experiment under well-watered (75% plant available water, PAW) and drought (25% PAW) conditions. Transpiration rate was analyzed for the underlying main morphological (leaf area duration) and physiological (stomata conductance) factors. Combining both morphological and physiological regulation of transpiration, four distinct water use types were identified. Most landraces had high transpiration rates either due to extensive leaf area (area types) or both large leaf areas together with high stomata conductance (spender types). All modern cultivars were distinguished by high stomata conductance with comparatively compact canopies (conductance types). Only few landraces were water saver types with both small canopy and low stomata conductance. During early growth, genotypes with large leaf area had high dry-matter accumulation under both well-watered and drought conditions compared to genotypes with compact stature. However, high stomata conductance was the basis to achieve high dry matter per unit leaf area, indicating high assimilation capacity as a key for productivity in modern cultivars. We conclude that the identified water use strategies based on early growth shoot phenotyping combined with stomata conductance provide an appropriate framework for targeted selection of distinct pre-breeding material adapted to different types of water limited environments. PMID:27547208

Coordination of growth in root and shoot apices by AIL/PLT transcription factors

NARCIS (Netherlands)

Scheres, Ben; Krizek, Beth A.

2018-01-01

Growth at the root tip and organ generation at the shoot tip depend on the proper functioning of apical meristems and the transitioning of meristematic cell descendants from a proliferating state to cell elongation and differentiation. Members of the AINTEGUMENTA-LIKE/PLETHORA (AIL/PLT)

Effect of irrigation on needle morphology, shoot and stem growth in a drought-exposed Pinus sylvestris forest.

Science.gov (United States)

Dobbertin, Matthias; Eilmann, Britta; Bleuler, Peter; Giuggiola, Arnaud; Graf Pannatier, Elisabeth; Landolt, Werner; Schleppi, Patrick; Rigling, Andreas

2010-03-01

In Valais, Switzerland, Scots pines (Pinus sylvestris L.) are declining, mainly following drought. To assess the impact of drought on tree growth and survival, an irrigation experiment was initiated in 2003 in a mature pine forest, approximately doubling the annual precipitation. Tree crown transparency (lack of foliage) and leaf area index (LAI) were annually assessed. Seven irrigated and six control trees were felled in 2006, and needles, stem discs and branches were taken for growth analysis. Irrigation in 2004 and 2005, both with below-average precipitation, increased needle size, area and mass, stem growth and, with a 1-year delay, shoot length. This led to a relative decrease in tree crown transparency (-14%) and to an increase in stand LAI (+20%). Irrigation increased needle length by 70%, shoot length by 100% and ring width by 120%, regardless of crown transparency. Crown transparency correlated positively with mean needle size, shoot length and ring width and negatively with specific leaf area. Trees with high crown transparency (low growth, short needles) experienced similar increases in needle mass and growth with irrigation than trees with low transparency (high growth, long needles), indicating that seemingly declining trees were able to 'recover' when water supply became sufficient. A simple drought index before and during the irrigation explained most of the variation found in the parameters for both irrigated and control trees.

Proteomic analysis of shoot tissue during photoperiod induced growth cessation in V. riparia Michx. grapevines

Directory of Open Access Journals (Sweden)

Victor Kim J

2010-08-01

Full Text Available Abstract Background Growth cessation, cold acclimation and dormancy induction in grapevines and other woody perennial plants native to temperate continental climates is frequently triggered by short photoperiods. The early induction of these processes by photoperiod promotes winter survival of grapevines in cold temperate zones. Examining the molecular processes, in particular the proteomic changes in the shoot, will provide greater insight into the signaling cascade that initiates growth cessation and dormancy induction. To begin understanding transduction of the photoperiod signal, Vitis riparia Michx. grapevines that had grown for 35 days in long photoperiod (long day, LD, 15 h were subjected to either a continued LD or a short photoperiod (short day, SD, 13 h treatment. Shoot tips (4-node shoot terminals were collected from each treatment at 7 and 28 days of LD and SD for proteomic analysis via two-dimensional (2D gel electrophoresis. Results Protein profiles were characterized in V. riparia shoot tips during active growth or SD induced growth cessation to examine physiological alterations in response to differential photoperiod treatments. A total of 1054 protein spots were present on the 2D gels. Among the 1054 proteins, 216 showed differential abundance between LD and SD (≥ two-fold ratio, p-value ≤ 0.05. After 7 days, 39 protein spots were more abundant in LD and 30 were more abundant in SD. After 28 days, 93 protein spots were more abundant in LD and 54 were more abundant in SD. MS/MS spectrometry was performed to determine the functions of the differentially abundant proteins. Conclusions The proteomics analysis uncovered a portion of the signal transduction involved in V. riparia grapevine growth cessation and dormancy induction. Different enzymes of the Calvin-Benson cycle and glutamate synthetase isoforms were more abundant either in LD or SD treatments. In LD tissues the significantly differentially more abundant proteins

Proteomic analysis of shoot tissue during photoperiod induced growth cessation in V. riparia Michx. grapevines

Science.gov (United States)

2010-01-01

Background Growth cessation, cold acclimation and dormancy induction in grapevines and other woody perennial plants native to temperate continental climates is frequently triggered by short photoperiods. The early induction of these processes by photoperiod promotes winter survival of grapevines in cold temperate zones. Examining the molecular processes, in particular the proteomic changes in the shoot, will provide greater insight into the signaling cascade that initiates growth cessation and dormancy induction. To begin understanding transduction of the photoperiod signal, Vitis riparia Michx. grapevines that had grown for 35 days in long photoperiod (long day, LD, 15 h) were subjected to either a continued LD or a short photoperiod (short day, SD, 13 h) treatment. Shoot tips (4-node shoot terminals) were collected from each treatment at 7 and 28 days of LD and SD for proteomic analysis via two-dimensional (2D) gel electrophoresis. Results Protein profiles were characterized in V. riparia shoot tips during active growth or SD induced growth cessation to examine physiological alterations in response to differential photoperiod treatments. A total of 1054 protein spots were present on the 2D gels. Among the 1054 proteins, 216 showed differential abundance between LD and SD (≥ two-fold ratio, p-value ≤ 0.05). After 7 days, 39 protein spots were more abundant in LD and 30 were more abundant in SD. After 28 days, 93 protein spots were more abundant in LD and 54 were more abundant in SD. MS/MS spectrometry was performed to determine the functions of the differentially abundant proteins. Conclusions The proteomics analysis uncovered a portion of the signal transduction involved in V. riparia grapevine growth cessation and dormancy induction. Different enzymes of the Calvin-Benson cycle and glutamate synthetase isoforms were more abundant either in LD or SD treatments. In LD tissues the significantly differentially more abundant proteins included flavonoid

Effects of Aqueous Shoot Extract of Tithonia diversifolia on the Growth of Seedlings of Monodora tenuifolia (Benth., Dialium guineense (Willd. and Hildegardia barteri (Mast. Kosterm

Directory of Open Access Journals (Sweden)

SAMSON OLAJIDE OKE

2011-05-01

Full Text Available The allelopathic effects of fresh shoot aqueous extract of Tithonia diversifolia (Hemsl. A.Gray, an invasive species introduced into Africa from North and Central America, on the growth of seedlings of three woody species: Monodora tenuifolia, Dialium guineense and Hildegardia barteri were investigated. The fresh shoot aqueous extract of Tithonia diversifolia was applied to the established seedlings of the three woody species over a period of ten weeks. The fresh shoot aqueous extract of Tithonia diversifolia had a significant effect (inhibitory and stimulatory on growth parameters such as shoot hThe allelopathic effects of fresh shoot aqueous extract of Tithonia diversifolia (Hemsl. A. Gray, an invasive species introduced into Africa from North and Central America, on the growth of seedlings of three woody species: Monodora tenuifolia, Dialium guineense and Hildegardia barteri were investigated. The fresh shoot aqueous extract of Tithonia diversifolia was applied to the established seedlings of the three woody species over a period of ten weeks. The fresh shoot aqueous extract of Tithonia diversifolia had a significant effect (inhibitory and stimulatory on growth parameters such as shoot height, leaf area, number of leaves and chlorophyll content of the three woody species.The study revealed that the fresh shoot aqueous extract of Tithonia diversofolia have different effects (inhibitory and stimulatory on the seedlings and the mode of action depends on the associated woody plant species.eight, leaf area, number of leaves and chlorophyll content of the three woody species.The study revealed that the fresh shoot aqueous extract of Tithonia diversofolia have different effects (inhibitory and stimulatory on the seedlings and the mode of action depends on the associated woody plant species.

Brief Report: Examining children’s disruptive behavior in the wake of trauma - A two-piece growth curve model before and after a school shooting

Science.gov (United States)

Liao, Yue; Shonkoff, Eleanor T.; Barnett, Elizabeth; Wen, CK Fred; Miller, Kimberly A.; Eddy, J. Mark

2015-01-01

School shootings may have serious negative impacts on children years after the event. Previous research suggests that children exposed to traumatic events experience heightened fear, anxiety, and feelings of vulnerability, but little research has examined potential aggressive and disruptive behavioral reactions. Utilizing a longitudinal dataset in which a local school shooting occurred during the course of data collection, this study sought to investigate whether the trajectory of disruptive behaviors was affected by the shooting. A two-piece growth curve model was used to examine the trajectory of disruptive behaviors during the pre-shooting years (i.e., piece one) and post-shooting years (i.e., piece two). Results indicated that the two-piece growth curve model fit the data better than the one-piece model and that the school shooting precipitated a faster decline in aggressive behaviors. This study demonstrated a novel approach to examining effects of an unexpected traumatic event on behavioral trajectories using an existing longitudinal data set. PMID:26298676

Abscisic Acid Regulation of Root Hydraulic Conductivity and Aquaporin Gene Expression Is Crucial to the Plant Shoot Growth Enhancement Caused by Rhizosphere Humic Acids.

Science.gov (United States)

Olaetxea, Maite; Mora, Verónica; Bacaicoa, Eva; Garnica, María; Fuentes, Marta; Casanova, Esther; Zamarreño, Angel M; Iriarte, Juan C; Etayo, David; Ederra, Iñigo; Gonzalo, Ramón; Baigorri, Roberto; García-Mina, Jose M

2015-12-01

The physiological and metabolic mechanisms behind the humic acid-mediated plant growth enhancement are discussed in detail. Experiments using cucumber (Cucumis sativus) plants show that the shoot growth enhancement caused by a structurally well-characterized humic acid with sedimentary origin is functionally associated with significant increases in abscisic acid (ABA) root concentration and root hydraulic conductivity. Complementary experiments involving a blocking agent of cell wall pores and water root transport (polyethylenglycol) show that increases in root hydraulic conductivity are essential in the shoot growth-promoting action of the model humic acid. Further experiments involving an inhibitor of ABA biosynthesis in root and shoot (fluridone) show that the humic acid-mediated enhancement of both root hydraulic conductivity and shoot growth depended on ABA signaling pathways. These experiments also show that a significant increase in the gene expression of the main root plasma membrane aquaporins is associated with the increase of root hydraulic conductivity caused by the model humic acid. Finally, experimental data suggest that all of these actions of model humic acid on root functionality, which are linked to its beneficial action on plant shoot growth, are likely related to the conformational structure of humic acid in solution and its interaction with the cell wall at the root surface. © 2015 American Society of Plant Biologists. All Rights Reserved.

Brief report: Examining children's disruptive behavior in the wake of trauma - A two-piece growth curve model before and after a school shooting.

Science.gov (United States)

Liao, Yue; Shonkoff, Eleanor T; Barnett, Elizabeth; Wen, C K Fred; Miller, Kimberly A; Eddy, J Mark

2015-10-01

School shootings may have serious negative impacts on children years after the event. Previous research suggests that children exposed to traumatic events experience heightened fear, anxiety, and feelings of vulnerability, but little research has examined potential aggressive and disruptive behavioral reactions. Utilizing a longitudinal dataset in which a local school shooting occurred during the course of data collection, this study sought to investigate whether the trajectory of disruptive behaviors was affected by the shooting. A two-piece growth curve model was used to examine the trajectory of disruptive behaviors during the pre-shooting years (i.e., piece one) and post-shooting years (i.e., piece two). Results indicated that the two-piece growth curve model fit the data better than the one-piece model and that the school shooting precipitated a faster decline in aggressive behaviors. This study demonstrated a novel approach to examining effects of an unexpected traumatic event on behavioral trajectories using an existing longitudinal data set. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Effect of biweekly shoot tip harvests on the growth and yield of Georgia Jet sweet potato grown hydroponically

Science.gov (United States)

Ogbuehi, Cyriacus R.; Loretan, Phil A.; Bonsi, C. K.; Hill, Walter A.; Morris, Carlton E.; Biswas, P. K.; Mortley, Desmond G.

1989-01-01

Sweet potato shoot tips have been shown to be a nutritious green vegetable. A study was conducted to determine the effect of biweekly shoot tip harvests on the growth and yield of Georgia Jet sweet potato grown in the greenhouse using the nutrient film technique (NFT). The nutrient solution consisted of a modified half Hoagland solution. Biweekly shoot tip harvests, beginning 42 days after planting, provided substantial amounts of vegetable greens and did not affect the fresh and dry foliage weights or the storage root number and fresh and dry storage root weights at final harvest. The rates of anion and cation uptake were not affected by tip harvests.

Salicylic acid antagonizes abscisic acid inhibition of shoot growth and cell cycle progression in rice

Science.gov (United States)

Meguro, Ayano; Sato, Yutaka

2014-04-01

We analysed effects of abscisic acid (ABA, a negative regulatory hormone), alone and in combination with positive or neutral hormones, including salicylic acid (SA), on rice growth and expression of cell cycle-related genes. ABA significantly inhibited shoot growth and induced expression of OsKRP4, OsKRP5, and OsKRP6. A yeast two-hybrid assay showed that OsKRP4, OsKRP5, and OsKRP6 interacted with OsCDKA;1 and/or OsCDKA;2. When SA was simultaneously supplied with ABA, the antagonistic effect of SA completely blocked ABA inhibition. SA also blocked ABA inhibition of DNA replication and thymidine incorporation in the shoot apical meristem. These results suggest that ABA arrests cell cycle progression by inducing expression of OsKRP4, OsKRP5, and OsKRP6, which inhibit the G1/S transition, and that SA antagonizes ABA by blocking expression of OsKRP genes.

Foliar Abscisic Acid-To-Ethylene Accumulation and Response Regulate Shoot Growth Sensitivity to Mild Drought in Wheat

Science.gov (United States)

Valluru, Ravi; Davies, William J.; Reynolds, Matthew P.; Dodd, Ian C.

2016-01-01

Although, plant hormones play an important role in adjusting growth in response to environmental perturbation, the relative contributions of abscisic acid (ABA) and ethylene remain elusive. Using six spring wheat genotypes differing for stress tolerance, we show that young seedlings of the drought-tolerant (DT) group maintained or increased shoot dry weight (SDW) while the drought-susceptible (DS) group decreased SDW in response to mild drought. Both the DT and DS groups increased endogenous ABA and ethylene concentrations under mild drought compared to control. The DT and DS groups exhibited different SDW response trends, whereby the DS group decreased while the DT group increased SDW, to increased concentrations of ABA and ethylene under mild drought, although both groups decreased ABA/ethylene ratio under mild drought albeit at different levels. We concluded that SDW of the DT and DS groups might be distinctly regulated by specific ABA:ethylene ratio. Further, a foliar-spray of low concentrations (0.1 μM) of ABA increased shoot relative growth rate (RGR) in the DS group while ACC (1-aminocyclopropane-1-carboxylic acid, ethylene precursor) spray increased RGR in both groups compared to control. Furthermore, the DT group accumulated a significantly higher galactose while a significantly lower maltose in the shoot compared to the DS group. Taken all together, these results suggest an impact of ABA, ethylene, and ABA:ethylene ratio on SDW of wheat seedlings that may partly underlie a genotypic variability of different shoot growth sensitivities to drought among crop species under field conditions. We propose that phenotyping based on hormone accumulation, response and hormonal ratio would be a viable, rapid, and an early–stage selection tool aiding genotype selection for stress tolerance. PMID:27148292

Experimental drought and heat can delay phenological development and reduce foliar and shoot growth in semiarid trees.

Science.gov (United States)

Adams, Henry D; Collins, Adam D; Briggs, Samuel P; Vennetier, Michel; Dickman, L Turin; Sevanto, Sanna A; Garcia-Forner, Núria; Powers, Heath H; McDowell, Nate G

2015-11-01

Higher temperatures associated with climate change are anticipated to trigger an earlier start to the growing season, which could increase the terrestrial C sink strength. Greater variability in the amount and timing of precipitation is also expected with higher temperatures, bringing increased drought stress to many ecosystems. We experimentally assessed the effects of higher temperature and drought on the foliar phenology and shoot growth of mature trees of two semiarid conifer species. We exposed field-grown trees to a ~45% reduction in precipitation with a rain-out structure ('drought'), a ~4.8 °C temperature increase with open-top chambers ('heat'), and a combination of both simultaneously ('drought + heat'). Over the 2013 growing season, drought, heat, and drought + heat treatments reduced shoot and needle growth in piñon pine (Pinus edulis) by ≥39%, while juniper (Juniperus monosperma) had low growth and little response to these treatments. Needle emergence on primary axis branches of piñon pine was delayed in heat, drought, and drought + heat treatments by 19-57 days, while secondary axis branches were less likely to produce needles in the heat treatment, and produced no needles at all in the drought + heat treatment. Growth of shoots and needles, and the timing of needle emergence correlated inversely with xylem water tension and positively with nonstructural carbohydrate concentrations. Our findings demonstrate the potential for delayed phenological development and reduced growth with higher temperatures and drought in tree species that are vulnerable to drought and reveal potential mechanistic links to physiological stress responses. Climate change projections of an earlier and longer growing season with higher temperatures, and consequent increases in terrestrial C sink strength, may be incorrect for regions where plants will face increased drought stress with climate change. © 2015 John Wiley & Sons Ltd.

High Frequency Multiple Shoot Induction of Curculigo orchioides Gaertn.: Shoot Tip V/S Rhizome Disc

Directory of Open Access Journals (Sweden)

K. S. Nagesh

2008-09-01

Full Text Available Curculigo orchioides Gaertn. is an endangered medicinal plant with anticancer properties. The rhizome and tuberous roots of the plant have been used extensively in India in indigenous medicine. Due to its multiple uses, the demand for Curculigo orchioides is constantly on the rise; however, the supply is rather erratic and inadequate. Destructive harvesting, combined with habitat destruction in the form of deforestation has aggravated the problem. The plant is now considered ‘endangered’ in its natural habitat. Therefore, the need for conservation of this plant is crucial. Here, we describe a successful protocol for multiple shoot induction of C. orchioides using shoot tip and rhizome disc. We find that proximal rhizome discs are optimal for high frequency shoot bud formation than shoot tip and distal rhizome disc. We observed a synergistic effect between 6-benzylaminopurine (BAP and kinetin (KN (each at 1 mg/L on the regeneration of shoot buds from proximal rhizome disc than shoot tip explant. Optimum root induction was achieved on half-strength MS liquid medium supplemented with 1 mg/L of indole-3-butyric acid (IBA. The in vitro raised plantlets were acclimatized in green house and successfully transplanted to natural condition with 90% survival.

Germination, seedling growth and relative water content of shoot in ...

African Journals Online (AJOL)

STORAGESEVER

2008-08-18

Aug 18, 2008 ... (mg), root : shoot length (R:S) ratio, and relative water content of shoot (RWC, %) were investigated in this study. The results ... seedlings may provide an advantage by allowing access ... Residual chlorine was eliminated by.

The Effect of Plant Growth Regulators on Shoot Proliferation and Rooting of Crataegus Pseudohetrophylla Pojark. Via in Vitro Culture

Directory of Open Access Journals (Sweden)

F. Ahmadloo

2015-12-01

Full Text Available Crataegus is a tree species from Rosaceae family with medicinal, ornamental and commercial utilizations. Effect of different concentrations of plant growth regulators on shoot proliferation of Crataegus pseudohetrophylla Pojark. via in vitro culture was studied using single node explants. The grown shoots were transferred to MS medium supplemented with different concentrations of cytokinins (BAP, KIN, 2iP and Zt in combination with NAA in 30 treatments, with 3 replications and each replication included 5 explants. Data were recorded after 3 subcultures. For rooting, basal end of shoots were dipped into 300mg/l of IBA at different durations (0, 5, 10, 20, 30, 40, 50 and 60 minutes, then the dipped shoots were cultured on hormone free 1/2 VS medium. The results of analysis of variance showed that there were significant differences in all of the traits. Results indicated that the highest number of shoots (39.33 was obtained on medium containing 8 mg / l BAP plus 2 mg / l NAA. The highest shoot length (4.67 cm and leaf size (3.73 cm was achieved on 7 mg / l BAP plus 2 mg / l NAA and 2 mg / l Zt plus 1 mg / l NAA, respectively. The highest rate of rooting (33.33% and root number (4n were induced on shoots dipped for 40 minutes in 300 mg / l IBA.

Rosette growth of shoots in chrysanthemum (Dendranthema grandiflora Tzvelev) as a result of in vitro propagation of plants and gamma irradiation used for mutation induction

International Nuclear Information System (INIS)

Jerzy, M.; Zalewska, M.; Lema, J.

1999-01-01

Rosette growth of chrysanthemum shoots in 'Mrs. R.C. Puling' was observed after in vitro propagation with explants obtained from vernalised and non-vernalised stock plants. The phenomenon was also observed as a result of the exposure of leaf explants to gamma radiation used for in vitro regeneration of plants in mutation induction. The higher the irradiation dose, the more considerable the rosette growth. Following the 4th pinching of shoot tips, only elongating growth of plants was observed

Water Deficit and Abscisic Acid Cause Differential Inhibition of Shoot versus Root Growth in Soybean Seedlings : Analysis of Growth, Sugar Accumulation, and Gene Expression.

Science.gov (United States)

Creelman, R A; Mason, H S; Bensen, R J; Boyer, J S; Mullet, J E

1990-01-01

Roots often continue to elongate while shoot growth is inhibited in plants subjected to low-water potentials. The cause of this differential response to water deficit was investigated. We examined hypocotyl and root growth, polysome status and mRNA populations, and abscisic acid (ABA) content in etiolated soybean (Glycine max [L.] Merr. cv Williams) seedlings whose growth was inhibited by transfer to low-water potential vermiculite or exogenous ABA. Both treatments affected growth and dry weight in a similar fashion. Maximum inhibition of hypocotyl growth occurred when internal ABA levels (modulated by ABA application) reached the endogenous level found in the elongating zone of seedlings grown in water-deficient vermiculite. Conversely, root growth was affected to only a slight extent in low-water potential seedlings and by most ABA treatments (in some, growth was promoted). In every seedling section examined, transfer of seedlings into low-water potential vermiculite caused ABA levels to increase approximately 5- to 10-fold over that found in well-watered seedlings. Changes in soluble sugar content, polysome status, and polysome mRNA translation products seen in low-water potential seedlings did not occur with ABA treatments sufficient to cause significant inhibition of hypocotyl elongation. These data suggest that both variation in endogenous ABA levels, and differing sensitivity to ABA in hypocotyls and roots can modulate root/shoot growth ratios. However, exogenous ABA did not induce changes in sugar accumulation, polysome status, and mRNA populations seen after transfer into low-water potential vermiculite.

CO2 enrichment inhibits shoot nitrate assimilation in C3 but not C4 plants and slows growth under nitrate in C3 plants.

Science.gov (United States)

Bloom, Arnold J; Asensio, Jose Salvador Rubaio; Randall, Lesley; Rachmilevitch, Shimon; Cousins, Asaph B; Carlisle, Eli A

2012-02-01

The CO2 concentration in Earth's atmosphere may double during this century. Plant responses to such an increase depend strongly on their nitrogen status, but the reasons have been uncertain. Here, we assessed shoot nitrate assimilation into amino acids via the shift in shoot CO2 and O2 fluxes when plants received nitrate instead of ammonium as a nitrogen source (deltaAQ). Shoot nitrate assimilation became negligible with increasing CO2 in a taxonomically diverse group of eight C3 plant species, was relatively insensitive to CO2 in three C4 species, and showed an intermediate sensitivity in two C3-C4 intermediate species. We then examined the influence of CO2 level and ammonium vs. nitrate nutrition on growth, assessed in terms of changes in fresh mass, of several C3 species and a Crassulacean acid metabolism (CAM) species. Elevated CO2 (720 micromol CO2/mol of all gases present) stimulated growth or had no effect in the five C3 species tested when they received ammonium as a nitrogen source but inhibited growth or had no effect if they received nitrate. Under nitrate, two C3 species grew faster at sub-ambient (approximately 310 micromol/mol) than elevated CO2. A CAM species grew faster at ambient than elevated or sub-ambient CO2 under either ammonium or nitrate nutrition. This study establishes that CO2 enrichment inhibits shoot nitrate assimilation in a wide variety of C3 plants and that this phenomenon can have a profound effect on their growth. This indicates that shoot nitrate assimilation provides an important contribution to the nitrate assimilation of an entire C3 plant. Thus, rising CO2 and its effects on shoot nitrate assimilation may influence the distribution of C3 plant species.

The role of resilience and gratitude in posttraumatic stress and growth following a campus shooting.

Science.gov (United States)

Vieselmeyer, Julie; Holguin, Jeff; Mezulis, Amy

2017-01-01

This study investigated the role of resilience and gratitude in the relationship between trauma exposure, posttraumatic stress (PTS), and posttraumatic growth (PTG) following the campus shooting at Seattle Pacific University. The prevalence of community traumatic events such as school shootings has increased dramatically in the last decade. However, a significant number of individuals report positive changes such as enhanced appreciation for life, suggesting that some people are able to convert adverse experiences into personal growth. The purpose of this study was to understand characteristics about trauma and protective characteristics that contribute to PTG. Participants were 359 students, faculty, and staff (75% female; mean age = 27.26, SD = 12.61) enrolled or employed the day the shooting took place. Approximately four months following the event respondents completed self-report questionnaires about trauma exposure (i.e., physical and emotional proximity), PTS symptoms, PTG, resilience, and gratitude. Results supported our moderated-mediation hypothesis (B = 3.97, t = 4.11, 95th confidence interval [2.08, 5.88], p gratitude can be conceptualized as protective mechanisms, with resilience operating to prevent adverse outcomes while gratitude may promote positive outcomes following trauma. Given the prevalence of lifetime trauma, findings indicate that mental health professionals should consider a multifaceted approach to buffer the effects of trauma by preventatively cultivating resilience and enhancing gratitude in posttrauma interventions as a means to decrease PTS and increase PTG. Additional research is needed to understand how individuals develop positive traits as both protective and coping mechanisms. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The effect of tillage intensity on soil structure and winter wheat root/shoot growth

DEFF Research Database (Denmark)

Munkholm, Lars Juhl; Hansen, Elly Møller; Olesen, Jørgen E

2008-01-01

was followed during the growing seasons using spectral reflectance and mini-rhizotron measurements, respectively. A range of soil physical properties were measured. We found decreased early season shoot and root growth with decreasing tillage intensity. Differences diminished later in the growing season...... of this study was to investigate the effect of tillage intensity on crop growth dynamics and soil structure. A tillage experiment was established in autumn 2002 on two Danish sandy loams (Foulum and Flakkebjerg) in a cereal-based crop rotation. The tillage systems included in this study were direct drilling (D...... with decreasing tillage intensity for the first year winter wheat at Foulum. In general ploughing resulted in the highest grain yields. This study highlights the important interaction between soil structure and crop growth dynamics....

Water Deficit and Abscisic Acid Cause Differential Inhibition of Shoot versus Root Growth in Soybean Seedlings 1

Science.gov (United States)

Creelman, Robert A.; Mason, Hugh S.; Bensen, Robert J.; Boyer, John S.; Mullet, John E.

1990-01-01

Roots often continue to elongate while shoot growth is inhibited in plants subjected to low-water potentials. The cause of this differential response to water deficit was investigated. We examined hypocotyl and root growth, polysome status and mRNA populations, and abscisic acid (ABA) content in etiolated soybean (Glycine max [L.] Merr. cv Williams) seedlings whose growth was inhibited by transfer to low-water potential vermiculite or exogenous ABA. Both treatments affected growth and dry weight in a similar fashion. Maximum inhibition of hypocotyl growth occurred when internal ABA levels (modulated by ABA application) reached the endogenous level found in the elongating zone of seedlings grown in water-deficient vermiculite. Conversely, root growth was affected to only a slight extent in low-water potential seedlings and by most ABA treatments (in some, growth was promoted). In every seedling section examined, transfer of seedlings into low-water potential vermiculite caused ABA levels to increase approximately 5- to 10-fold over that found in well-watered seedlings. Changes in soluble sugar content, polysome status, and polysome mRNA translation products seen in low-water potential seedlings did not occur with ABA treatments sufficient to cause significant inhibition of hypocotyl elongation. These data suggest that both variation in endogenous ABA levels, and differing sensitivity to ABA in hypocotyls and roots can modulate root/shoot growth ratios. However, exogenous ABA did not induce changes in sugar accumulation, polysome status, and mRNA populations seen after transfer into low-water potential vermiculite. Images Figure 6 Figure 7 PMID:16667248

Variation in shoot tolerance mechanisms not related to ion toxicity in barley

KAUST Repository

Tilbrook, Joanne

2017-09-27

Soil salinity can severely reduce crop growth and yield. Many studies have investigated salinity tolerance mechanisms in cereals using phenotypes that are relatively easy to measure. The majority of these studies measured the accumulation of shoot Na+ and the effect this has on plant growth. However, plant growth is reduced immediately after exposure to NaCl before Na+ accumulates to toxic concentrations in the shoot. In this study, nondestructive and destructive measurements are used to evaluate the responses of 24 predominately Australian barley (Hordeum vulgare L.) lines at 0, 150 and 250mMNaCl. Considerable variation for shoot tolerance mechanisms not related to ion toxicity (shoot ion-independent tolerance) was found, withsome lines being able to maintain substantial growth rates under salt stress, whereas others stopped growing. Hordeum vulgare spp. spontaneum accessions and barley landraces predominantly had the best shoot ion independent tolerance, although two commercial cultivars, Fathom and Skiff, also had high tolerance. The tolerance of cv. Fathom may be caused by a recent introgression from H. vulgare L. spp. spontaneum. This study shows that the most salt-tolerant barley lines are those that contain both shoot ion-independent tolerance and the ability to exclude Na+ from the shoot (and thus maintain high K+: Na+ ratios).

Variation in shoot tolerance mechanisms not related to ion toxicity in barley

KAUST Repository

Tilbrook, Joanne; Schilling, Rhiannon K.; Berger, Bettina; Garcia, Alexandre F.; Trittermann, Christine; Coventry, Stewart; Rabie, Huwaida; Brien, Chris; Nguyen, Martin; Tester, Mark A.; Roy, Stuart J.

2017-01-01

Soil salinity can severely reduce crop growth and yield. Many studies have investigated salinity tolerance mechanisms in cereals using phenotypes that are relatively easy to measure. The majority of these studies measured the accumulation of shoot Na+ and the effect this has on plant growth. However, plant growth is reduced immediately after exposure to NaCl before Na+ accumulates to toxic concentrations in the shoot. In this study, nondestructive and destructive measurements are used to evaluate the responses of 24 predominately Australian barley (Hordeum vulgare L.) lines at 0, 150 and 250mMNaCl. Considerable variation for shoot tolerance mechanisms not related to ion toxicity (shoot ion-independent tolerance) was found, withsome lines being able to maintain substantial growth rates under salt stress, whereas others stopped growing. Hordeum vulgare spp. spontaneum accessions and barley landraces predominantly had the best shoot ion independent tolerance, although two commercial cultivars, Fathom and Skiff, also had high tolerance. The tolerance of cv. Fathom may be caused by a recent introgression from H. vulgare L. spp. spontaneum. This study shows that the most salt-tolerant barley lines are those that contain both shoot ion-independent tolerance and the ability to exclude Na+ from the shoot (and thus maintain high K+: Na+ ratios).

Low temperature leaf photosynthesis of a Miscanthus germplasm collection correlates positively to shoot growth rate and specific leaf area

DEFF Research Database (Denmark)

Jiao, Xiurong; Sørensen, Kirsten Kørup; Andersen, Mathias Neumann

2016-01-01

and CO2 response curves were obtained from 11 of the genotypes, and shoot growth rate was measured under field conditions. Key Results A positive linear relationship was found between SLA and light-saturated photosynthesis (Asat) across genotypes, and also between shoot growth rate under cool field...... conditions and A1000 at 14 °C in a climate chamber. When lowering the temperature from 24 to 14 °C, one M. sacchariflorus exhibited significantly higher Asat and maximum photosynthetic rate in the CO2 response curve (Vmax) than other genotypes at 14 °C, except M. × giganteus ‘Hornum’. Several genotypes...... returned to their pre-chilling A1000 values when the temperature was increased to 24 °C after 24 d growth at 14 °C. Conclusions One M. sacchariflorus genotype had similar or higher photosynthetic capacity than M. × giganteus, and may be used for cultivation together with M. × giganteus or for breeding new...

Inhibition of tomato shoot growth by over-irrigation is linked to nitrogen deficiency and ethylene.

Science.gov (United States)

Fiebig, Antje; Dodd, Ian C

2016-01-01

Although physiological effects of acute flooding have been well studied, chronic effects of suboptimal soil aeration caused by over-irrigation of containerized plants have not, despite its likely commercial significance. By automatically scheduling irrigation according to soil moisture thresholds, effects of over-irrigation on soil properties (oxygen concentration, temperature and moisture), leaf growth, gas exchange, phytohormone [abscisic acid (ABA) and ethylene] relations and nutrient status of tomato (Solanum lycopersicum Mill. cv. Ailsa Craig) were studied. Over-irrigation slowly increased soil moisture and decreased soil oxygen concentration by 4%. Soil temperature was approximately 1°C lower in the over-irrigated substrate. Over-irrigating tomato plants for 2 weeks significantly reduced shoot height (by 25%) and fresh weight and total leaf area (by 60-70%) compared with well-drained plants. Over-irrigation did not alter stomatal conductance, leaf water potential or foliar ABA concentrations, suggesting that growth inhibition was not hydraulically regulated or dependent on stomatal closure or changes in ABA. However, over-irrigation significantly increased foliar ethylene emission. Ethylene seemed to inhibit growth, as the partially ethylene-insensitive genotype Never ripe (Nr) was much less sensitive to over-irrigation than the wild type. Over-irrigation induced significant foliar nitrogen deficiency and daily supplementation of small volumes of 10 mM Ca(NO3 )2 to over-irrigated soil restored foliar nitrogen concentrations, ethylene emission and shoot fresh weight of over-irrigated plants to control levels. Thus reduced nitrogen uptake plays an important role in inhibiting growth of over-irrigated plants, in part by stimulating foliar ethylene emission. © 2015 Scandinavian Plant Physiology Society.

Effect Of Gamma Rays And Growth Regulators On Explants Excised From In Vitro Shoots And Greenhouse Seedlings, Of Pepper (Capsicum Annum L.)

International Nuclear Information System (INIS)

Maarouf, A. A.; Kassem, M.

2004-01-01

This experiment was conducted on pepper (Capsicum annum L.) to compare the ability of the in vitro explants with those of greenhouse grown seedlings on shoot proliferation and callus formation and their ability to form plantlets and the effect of gamma irradiation and growth regulators on the shoot tip, hypocotyls and leaf tissue was used as laboratory explants, leaf tissue nodes and internodes were taken from greenhouse seedlings. 6- benzyla-minopurine (BAP) in different concentrations was combined with Indoleacertic acid (IAA) to know their effect on shoot proliferation, 2,4 - Dichlorophenoxy acetic acid (2,4- D) was used for callus formation, and use stimulation effect of gamma irradiation, potassium nitrat (KNO 3 ), Thidaiazurom (TDZ) and casine hydrolysate (CH) for plantlet formation. The results showed that the highest percentage of callus was obtained by in vitro hypocotyls and greenhouse grown nodes followed by in vitro leaf tissue thereafter greenhouse leaf tissue. The shoot tips were the lowest efficient explants in producing callus in both in vitro and greenhouse ones. The highest percentage of shooting resulted from shoot tip, hypocotyls and leaf tissue of in vitro explants, followed by shoot tip, nodes and internodes of greenhouse grown explants and the lowest percentage was recorded by leaf tissue. Highest percentage of shoot number was obtained form greenhouse grown shoot tip followed by in vitro shoot tip, hypocotyls and leaf tissue of greenhouse grown seedlings the internodes were the lowest efficient in producing shoots. The highest success in plantlet formation was caused by TDZ followed by gamma irradiation and the other treatments were equaled. (Authors)

Effects of Aqueous Shoot Extract of Tithonia diversifolia on the Growth of Seedlings of Monodora tenuifolia (Benth.), Dialium guineense (Willd.) and Hildegardia barteri (Mast.) Kosterm

OpenAIRE

SAMSON OLAJIDE OKE; Abisola Victoria AWOWOYIN; Shaid Remi OSENI; Emmanuel Lekan ADEDIWURA

2011-01-01

The allelopathic effects of fresh shoot aqueous extract of Tithonia diversifolia (Hemsl.) A.Gray, an invasive species introduced into Africa from North and Central America, on the growth of seedlings of three woody species: Monodora tenuifolia, Dialium guineense and Hildegardia barteri were investigated. The fresh shoot aqueous extract of Tithonia diversifolia was applied to the established seedlings of the three woody species over a period of ten weeks. The fresh shoot aqueous extract of Tit...

Competition-Induced Reductions in Soil Water Availability Reduced Pine Root Extension Rates

Science.gov (United States)

K.H. Ludovici; L.A. Morris

1997-01-01

The relationship between soil water availability, root extension, and shoot growth of loblolly pine seedlings (Pinus taeda L.) was evaluated in a rhizotron sand mixture in the absence and presence of crabgrass (Digitaria spp.) competition. Heights and diameters of seedlings grown with crabgrass were reduced 33 and SO%, respectively, compared with...

Giant panda foraging and movement patterns in response to bamboo shoot growth.

Science.gov (United States)

Zhang, Mingchun; Zhang, Zhizhong; Li, Zhong; Hong, Mingsheng; Zhou, Xiaoping; Zhou, Shiqiang; Zhang, Jindong; Hull, Vanessa; Huang, Jinyan; Zhang, Hemin

2018-03-01

Diet plays a pivotal role in dictating behavioral patterns of herbivorous animals, particularly specialist species. The giant panda (Ailuropoda melanoleuca) is well-known as a bamboo specialist. In the present study, the response of giant pandas to spatiotemporal variation of bamboo shoots was explored using field surveys and GPS collar tracking. Results show the dynamics in panda-bamboo space-time relationships that have not been previously articulated. For instance, we found a higher bamboo stump height of foraged bamboo with increasing elevation, places where pandas foraged later in spring when bamboo shoots become more fibrous and woody. The time required for shoots to reach optimum height for foraging was significantly delayed as elevation increased, a pattern which corresponded with panda elevational migration patterns beginning from the lower elevational end of Fargesia robusta distribution and gradually shifting upward until the end of the shooting season. These results indicate that giant pandas can respond to spatiotemporal variation of bamboo resources, such as available shoots. Anthropogenic interference of low-elevation F. robusta habitat should be mitigated, and conservation attention and increased monitoring should be given to F. robusta areas at the low- and mid-elevation ranges, particularly in the spring shooting season.

Effect of plant growth regulators on indirect shoot organogenesis of Ficus religiosa through seedling derived petiole segments

Directory of Open Access Journals (Sweden)

Mohsen Hesami

2018-06-01

Full Text Available Ficus religiosa is known as a long-lived multipurpose forest tree. The tree plays an important role for religious, medicinal, and ornamental purposes. However, the propagation rate of Ficus religiosa is low in natural habitat so the plant tissue culture techniques are an applicable method for multiplication of this valuable medicinal plants. Thus, the aim of this study is to understand the effect of different auxin/cytokinin ratios on indirect shoot organogenesis of this plant. According to our results, the maximum callus induction frequency (100% was obtained on Murashige and Skoog (MS medium supplemented with 0.5 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D plus 0.05 mg/l 6-benzylaminopurine (BAP from petiole segments. For shoot induction purpose, the yellow-brownish, friable, organogenic calli were inoculated on shoot induction medium. On MS medium supplemented with 1.5 mg/l BAP and 0.15 mg/l Indole-3-butyric acid (IBA, 96.66% of the petiole-derived calli responded with an average number of 3.56 shoots per culture. The highest root formation frequency (96.66%, root number (5.5, and root length (4.83 cm were achieved on MS medium containing 2.0 mg/l IBA plus 0.1 mg/l Naphthaleneacetic acid (NAA. The rooted shoots were successfully transferred to field condition and the substrate with the mixture of cocopeat and perlite (1:1 had the highest survival rate (96.66%. This is the first report of an effective in vitro organogenesis protocol for F. religiosa by indirect shoot organogenesis through axenic seedling derived petiole explants, which can be efficiently employed for conservation of this important medicinal plant species as well as the utilization of active biomolecules. Keywords: Callus formation, Multiplication, Acclimatization, Growth regulators ratio

Enhanced root and shoot growth of wheat (Triticum aestivum L.) by Trichoderma harzianum from Turkey.

Science.gov (United States)

Kucuk, Cigdem

2014-01-01

It is well known that Trichoderma species can be used as biocontrol and plant growth promote agent. In this study, Trichoderma harzianum isolates were evaluated for their growth promotion effects on wheat in greenhouse experiments. Two isolates of T. harzianum were used. The experimental design was a randomized complete block with three replications. Seeds were inoculated with conidial suspensions of each isolate. Wheat plants grown in steriled soil in pots. T. harzianum T8 and T15 isolates increased wheat length, root dry weight and shoot dry weight according to untreated control. Turkish isolates T8 and T15 did not produce damage in seeds nor in plants.

Spine micromorphology of normal and hyperhydric Mammillaria gracilis Pfeiff. (Cactaceae) shoots.

Science.gov (United States)

Peharec, P; Posilović, H; Balen, B; Krsnik-Rasol, M

2010-07-01

Artificial conditions of tissue culture affect growth and physiology of crassulacean acid metabolism plants which often results in formation of hyperhydric shoots. In in vitro conditions Mammillaria gracilis Pfeiff. (Cactaceae) growth switches from organized to unorganized way, producing a habituated organogenic callus which simultaneously regenerates morphologically normal as well as altered hyperhydric shoots. In this study, influence of tissue culture conditions on morphology of cactus spines of normal and hyperhydric shoots was investigated. Spines of pot-grown Mammillaria plants and of in vitro regenerated shoots were examined with stereo microscope and scanning electron microscope. The pot-grown plants had 16-17 spines per areole. In vitro grown normal shoots, even though they kept typical shoot morphology, had lower number of spines (11-12) and altered spine morphology. This difference was even more pronounced in spine number (six to seven) and morphology of the hyperhydric shoots. Scanning electron microscopy analysis revealed remarkable differences in micromorphology of spine surface between pot-grown and in vitro grown shoots. Spines of in vitro grown normal shoots showed numerous long trichomes, which were more elongated on spines of the hyperhydric shoots; the corresponding structures on spine surface of pot-grown plants were noticed only as small protrusions. Scanning electron microscopy morphometric studies showed that the spines of pot-grown plants were significantly longer compared to the spines of shoots grown in tissue culture. Moreover, transverse section shape varies from elliptical in pot-grown plants to circular in normal and hyperhydric shoots grown in vitro. Cluster and correspondence analyses performed on the scanning electron microscope obtained results suggest great variability among spines of pot-grown plants. Spines of in vitro grown normal and hyperhydric shoots showed low level of morphological variation among themselves despite the

Radiographing roots and shoots

International Nuclear Information System (INIS)

Shariffah Noor Khamseah Al Idid

1985-01-01

The effect of seed orientation on germination time and on shoot and root growth patterns is studied. Neutron radiography is used to observe the development of 4 types of plants, maize, greenpea, soya bean and padi. These plants were grown in varying orientations; sand sizes, sand thicknesses, and level of water content. Radiography of the seeds and plants were obtained for time exposure ranging from 3-12 hours and at reactor thermal power level, ranging from 500-750 kilowatts. Results obtained showed that seeds planted in varying orientations need different length of time for shoot emergence. Neutron radiography is now developed to other areas of non-industrial applications in Malaysia. (A.J.)

Light requirement for shoot regeneration in horseradish hairy roots.

Science.gov (United States)

Saitou, T; Kamada, H; Harada, H

1992-08-01

Hairy roots of horseradish (Armoracia rusticana) were induced by inoculation with Agrobacterium rhizogenes harboring Ri plasmid and cultured on phytohormone-free Murashige and Skoog medium after eliminating the bacteria. Hairy roots grew vigorously and sometimes formed yellowish calli under dark conditions. On the other hand, growth of hairy roots stopped after several weeks of culture with light, then shoots were regenerated. Frequency of shoot formation from hairy roots increased as the culture period in light lengthened and the light intensity increased. The shoot regeneration was induced by treatment with white or red light, but not with far-red light. Shoot regeneration by red light was inhibited by following treatment with far-red light. Red and far-red light reversibly affected shoot regeneration. Excised roots of nontransformed plants grew quite slowly on phytohormone-free Murashige and Skoog medium and occasionally formed shoots under white light conditions.

Radiosensitivity of in vitro Cultured Banana Shoot-Tips

International Nuclear Information System (INIS)

Elagamawy, M.R.

2002-01-01

Longitudinally dissected shoot apices of Grand Nain, Williams and Maghrabi banana cultivars were exposed to gamma irradiation with Cobalt 60 source at the doses of 0, 20, 40 and 60 Gy and immediately placed into proliferation medium. A number of micropropagation cycles after irradiation were necessary up to M1 V2 to M1 V4 stage to let mutated sectors developing into non-chimeric shoots. Radiosensitivity was evaluated by the rate of shoot proliferation and by the shoot fresh weight increase. Increasing gamma doses caused reduction in survival rates and average number of shoots. Grand Nain exhibited the highest multiplication- rate (3.1). The lower dose (20 Gy) enhanced shoot multiplication ratio specially in Williams and Maghrabi, which however decreased with increased doses. The doses of 20-40 Gy yielded Ld50, with sensible degree of shoot multiplication, which occurred hardly ever beyond 40 Gy. The dose of 60 Gy resulted 80% lethal shoot growth. Linear decrease in fresh weight was observed in post-irradiation recovery, notably in the Maghrabi. In contradictory vulnerable damage was observed in Williams which showed the highest fresh weight value. Shoot proliferation appeared generally on the surface of the corm. Root formation was observed without additional hormone. The roots were dark colored and was decreased with the increased of dosage

Variation of Maximum Tree Height and Annual Shoot Growth of Smith Fir at Various Elevations in the Sygera Mountains, Southeastern Tibetan Plateau

Science.gov (United States)

Wang, Yafeng; Čufar, Katarina; Eckstein, Dieter; Liang, Eryuan

2012-01-01

Little is known about tree height and height growth (as annual shoot elongation of the apical part of vertical stems) of coniferous trees growing at various altitudes on the Tibetan Plateau, which provides a high-elevation natural platform for assessing tree growth performance in relation to future climate change. We here investigated the variation of maximum tree height and annual height increment of Smith fir (Abies georgei var. smithii) in seven forest plots (30 m×40 m) along two altitudinal transects between 3,800 m and 4,200/4,390 m above sea level (a.s.l.) in the Sygera Mountains, southeastern Tibetan Plateau. Four plots were located on north-facing slopes and three plots on southeast-facing slopes. At each site, annual shoot growth was obtained by measuring the distance between successive terminal bud scars along the main stem of 25 trees that were between 2 and 4 m high. Maximum/mean tree height and mean annual height increment of Smith fir decreased with increasing altitude up to the tree line, indicative of a stress gradient (the dominant temperature gradient) along the altitudinal transect. Above-average mean minimum summer (particularly July) temperatures affected height increment positively, whereas precipitation had no significant effect on shoot growth. The time series of annual height increments of Smith fir can be used for the reconstruction of past climate on the southeastern Tibetan Plateau. In addition, it can be expected that the rising summer temperatures observed in the recent past and anticipated for the future will enhance Smith fir's growth throughout its altitudinal distribution range. PMID:22396738

miRNA and Degradome Sequencing Reveal miRNA and Their Target Genes That May Mediate Shoot Growth in Spur Type Mutant “Yanfu 6”

Science.gov (United States)

Song, Chunhui; Zhang, Dong; Zheng, Liwei; Zhang, Jie; Zhang, Baojuan; Luo, Wenwen; Li, Youmei; Li, Guangfang; Ma, Juanjuan; Han, Mingyu

2017-01-01

The spur-type growth habit in apple trees is characterized by short internodes, increased number of fruiting spurs, and compact growth that promotes flowering and facilitates management practices, such as pruning. The molecular mechanisms responsible for regulating spur-type growth have not been elucidated. In the present study, miRNAs and the expression of their potential target genes were evaluated in shoot tips of “Nagafu 2” (CF) and spur-type bud mutation “Yanfu 6” (YF). A total of 700 mature miRNAs were identified, including 202 known apple miRNAs and 498 potential novel miRNA candidates. A comparison of miRNA expression in CF and YF revealed 135 differentially expressed genes, most of which were downregulated in YF. YF also had lower levels of GA, ZR, IAA, and ABA hormones, relative to CF. Exogenous applications of GA promoted YF shoot growth. Based on the obtained results, a regulatory network involving plant hormones, miRNA, and their potential target genes is proposed for the molecular mechanism regulating the growth of YF. miRNA164, miRNA166, miRNA171, and their potential targets, and associated plant hormones, appear to regulate shoot apical meristem (SAM) growth. miRNA159, miRNA167, miRNA396, and their potential targets, and associated plant hormones appear to regulate cell division and internode length. This study provides a foundation for further studies designed to elucidate the mechanism underlying spur-type apple architecture. PMID:28424721

The genetic architecture of shoot-root covariation during seedling emergence of a desert tree, Populus euphratica.

Science.gov (United States)

Zhang, Miaomiao; Bo, Wenhao; Xu, Fang; Li, Huan; Ye, Meixia; Jiang, Libo; Shi, Chaozhong; Fu, Yaru; Zhao, Guomiao; Huang, Yuejiao; Gosik, Kirk; Liang, Dan; Wu, Rongling

2017-06-01

The coordination of shoots and roots is critical for plants to adapt to changing environments by fine-tuning energy production in leaves and the availability of water and nutrients from roots. To understand the genetic architecture of how these two organs covary during developmental ontogeny, we conducted a mapping experiment using Euphrates poplar (Populus euphratica), a so-called hero tree able to grow in the desert. We geminated intraspecific F 1 seeds of Euphrates Poplar individually in a tube to obtain a total of 370 seedlings, whose shoot and taproot lengths were measured repeatedly during the early stage of growth. By fitting a growth equation, we estimated asymptotic growth, relative growth rate, the timing of inflection point and duration of linear growth for both shoot and taproot growth. Treating these heterochronic parameters as phenotypes, a univariate mapping model detected 19 heterochronic quantitative trait loci (hQTLs), of which 15 mediate the forms of shoot growth and four mediate taproot growth. A bivariate mapping model identified 11 pleiotropic hQTLs that determine the covariation of shoot and taproot growth. Most QTLs detected reside within the region of candidate genes with various functions, thus confirming their roles in the biochemical processes underlying plant growth. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

Jatropha curcas L. Root Structure and Growth in Diverse Soils

Science.gov (United States)

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

2013-01-01

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

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

Science.gov (United States)

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

2013-01-01

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

Jatropha curcas L. Root Structure and Growth in Diverse Soils

Directory of Open Access Journals (Sweden)

Ofelia Andrea Valdés-Rodríguez

2013-01-01

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

Metabolic changes associated with shoot formation in tobacco callus cultures

Energy Technology Data Exchange (ETDEWEB)

Grady, K.L.

1982-08-01

Callus tissue derived from Nicotiana tabacum L. stem pith parenchyma cells was grown either on medium which maintains the callus in an undifferentiated state, or on medium which induces the formation of shoots. Two complementary types of studies were performed with the goal of establishing metabolic markers for the initiation of shoot formation: one designed to characterize the flow of radioactive sucrose into various metabolic pools, and one which allowed measurement of intermediary metabolite concentrations. In the former, callus tissue was incubated in (U-/sup 14/C)sucrose for periods up to one hour, and patterns of metabolite labelling in tissue grown on shoot-forming and non-shoot-forming media were compared. In the latter studies, tissue was grown for an entire subculture period on non-shoot-forming medium labelled with (U-/sup 14/C)sucrose, then subcultured to labelled non-shoot-forming or shoot-forming media, and sampled at intervals during the first week of growth. 189 references.

Metabolic changes associated with shoot formation in tobacco callus cultures

International Nuclear Information System (INIS)

Grady, K.L.

1982-08-01

Callus tissue derived from Nicotiana tabacum L. stem pith parenchyma cells was grown either on medium which maintains the callus in an undifferentiated state, or on medium which induces the formation of shoots. Two complementary types of studies were performed with the goal of establishing metabolic markers for the initiation of shoot formation: one designed to characterize the flow of radioactive sucrose into various metabolic pools, and one which allowed measurement of intermediary metabolite concentrations. In the former, callus tissue was incubated in [U- 14 C]sucrose for periods up to one hour, and patterns of metabolite labelling in tissue grown on shoot-forming and non-shoot-forming media were compared. In the latter studies, tissue was grown for an entire subculture period on non-shoot-forming medium labelled with [U- 14 C]sucrose, then subcultured to labelled non-shoot-forming or shoot-forming media, and sampled at intervals during the first week of growth. 189 references

Light Requirement for Shoot Regeneration in Horseradish Hairy Roots 1

Science.gov (United States)

Saitou, Tsutomu; Kamada, Hiroshi; Harada, Hiroshi

1992-01-01

Hairy roots of horseradish (Armoracia rusticana) were induced by inoculation with Agrobacterium rhizogenes harboring Ri plasmid and cultured on phytohormone-free Murashige and Skoog medium after eliminating the bacteria. Hairy roots grew vigorously and sometimes formed yellowish calli under dark conditions. On the other hand, growth of hairy roots stopped after several weeks of culture with light, then shoots were regenerated. Frequency of shoot formation from hairy roots increased as the culture period in light lengthened and the light intensity increased. The shoot regeneration was induced by treatment with white or red light, but not with far-red light. Shoot regeneration by red light was inhibited by following treatment with far-red light. Red and far-red light reversibly affected shoot regeneration. Excised roots of nontransformed plants grew quite slowly on phytohormone-free Murashige and Skoog medium and occasionally formed shoots under white light conditions. PMID:16669041

Lippia dulcis shoot cultures as a source of the sweet sesquiterpene hernandulcin.

Science.gov (United States)

Sauerwein, M; Flores, H E; Yamazaki, T; Shimomura, K

1991-04-01

The axenic shoot culture of Lippia dulcis Trev., Verbenaceae, was established on hormone-free Murashige-Skoog solid medium containing 3% sucrose. Shoots were cultured in various liquid or solid media. Woody Plant liquid medium was best for shoot multiplication, but the production of hernandulcin was relatively low. The highest hernandulcin content (2.9% dry wt) was obtained after 28 days of culture on Murashige-Skoog solid medium containing 2% sucrose. The addition of chitosan to the culture media enhanced the growth of shoots as well as the production of hernandulcin, especially with the liquid medium.

Peach Water Relations, Gas Exchange, Growth and Shoot Mortality under Water Deficit in Semi-Arid Weather Conditions

OpenAIRE

Rahmati, Mitra; Davarynejad, Gholam Hossein; G?nard, Michel; Bannayan, Mohammad; Azizi, Majid; Vercambre, Gilles

2015-01-01

In this study the sensitivity of peach tree (Prunus persica L.) to three water stress levels from mid-pit hardening until harvest was assessed. Seasonal patterns of shoot and fruit growth, gas exchange (leaf photosynthesis, stomatal conductance and transpiration) as well as carbon (C) storage/mobilization were evaluated in relation to plant water status. A simple C balance model was also developed to investigate sink-source relationship in relation to plant water status at the tree level. The...

THE EFFICIENCY OF SHOOT AND PLANTLET FORMATION OF Cephaelis ipecacuanha AFTER THREE SUBCULTURES IN VITRO

Directory of Open Access Journals (Sweden)

Osmar Alves Lameira

1994-12-01

Full Text Available Multiple adventitious shoot formed from internodal segments of Cephaelis ipecacuanha cultured 25 days on Gamborg basal medium (GAMBORG et al., 1968 supplemented with 6.66mM 6-benzylaminopurine there was a maximum of nine shoots per segment and an average of five shoots per segment formed. The presence of gibberellic acid in the subculture media promoted shoot elongation in all treatments. The shoots attained 3cm in height and rooting of 100% after 35 days of culturing upon Murashige and Skoog's basal medium (MS, added with 4.92mM indole-3-butyric acid, 0.87m gibberellic acid and 0.1% activated charcoal. Further growth was accelerated after the transfer to 1/2 MS without growth regulators. Rooted plantlets transferred to potting soil could be successfully established.

Growth responses of low-alpine dwarf-shrub heath species to nitrogen deposition and management

International Nuclear Information System (INIS)

Britton, Andrea J.; Fisher, Julia M.

2008-01-01

Nitrogen deposition is a continuing problem in European alpine regions. We hypothesised that, despite climatic limitations, low-alpine Calluna heathland would respond to nitrogen addition with increased shoot growth and flowering and that fire and grazing would modify responses. In a five-year study, 0-50 kg N ha -1 y -1 were added, combined with burning (+/-) and clipping (+/-). Calluna vulgaris responded with increased shoot extension, but effects on flowering were variable. Burning enhanced the positive effect of nitrogen addition and negative effects of clipping. Sub-dominant shrubs generally did not respond to nitrogen. C. vulgaris shoot extension was stimulated by nitrogen addition of 10 kg N ha -1 y -1 (above background) supporting suggestions that alpine heathlands are sensitive to low levels of nitrogen deposition. Increased C. vulgaris growth could negatively impact on important lichen components of this vegetation through increased shading and competition. Climatic factors constrain productivity in this community, but do not prevent rapid responses to nitrogen deposition by some species. - Low levels of N deposition increase productivity in alpine dwarf-shrub heath despite strong climatic constraints

Effect of acorn mass and size, and early shoot growth on one-year old container-grown RPM™ oak seedlings

Science.gov (United States)

Benjamin C. Grossman; Michael A. Gold; Daniel C. Dey

2003-01-01

The purpose of this study was to evaluate the influence of seed source, acorn mass and size, and early shoot growth on morphological traits of 1-year-old oak seedlings. Forested bottomlands in the Midwest have been greatly reduced in the past 150 years as a result of conversion to agriculture and recent catastrophic floods. Due to a lack of available hard mast, intense...

Fruit production and branching density affect shoot and whole-tree wood to leaf biomass ratio in olive.

Science.gov (United States)

Rosati, Adolfo; Paoletti, Andrea; Al Hariri, Raeed; Famiani, Franco

2018-02-14

The amount of shoot stem (i.e., woody part of the shoot) dry matter per unit shoot leaf dry matter (i.e., the shoot wood to leaf biomass ratio) has been reported to be lower in short shoots than in long ones, and this is related to the greater and earlier ability of short shoots to export carbon. This is important in fruit trees, since the greater and earlier carbon export ability of shoots with a lower wood to leaf biomass ratio improves fruit production. This ratio may vary with cultivars, training systems or plant age, but no study has previously investigated the possible effect of fruit production. In this study on two olive cultivars (i.e., Arbequina, with low growth rate, and Frantoio, with high growth rate) subject to different fruit production treatments, we found that at increasing fruit production, shoot length and shoot wood to leaf biomass ratio were proportionally reduced in the new shoots growing at the same time as the fruit. Specifically, fruit production proportionally reduced total new-shoot biomass, length, leaf area and average shoot length. With decreasing shoot length, shoot diameter, stem mass, internode length, individual leaf area and shoot wood to leaf biomass ratio also decreased. This may be viewed as a plant strategy to better support fruit growth in the current year, given the greater and earlier ability of short shoots to export carbon. Moreover, at the whole-tree level, the percentage of total tree biomass production invested in leaves was closely correlated with branching density, which differed significantly across cultivars. By branching more, Arbequina concentrates more shoots (thus leaves) per unit of wood (trunk, branches and root) mass, decreasing wood to leaf biomass ratio at the whole-tree level. Therefore, while, at the shoot level, shoot length determines shoot wood to leaf biomass ratio, at the canopy level branching density is also an important determinant of whole-tree wood to leaf biomass ratio. Whole-tree wood to leaf

Shoot- and root-borne cytokinin influences arbuscular mycorrhizal symbiosis.

Science.gov (United States)

Cosme, Marco; Ramireddy, Eswarayya; Franken, Philipp; Schmülling, Thomas; Wurst, Susanne

2016-10-01

The arbuscular mycorrhizal (AM) symbiosis is functionally important for the nutrition and growth of most terrestrial plants. Nearly all phytohormones are employed by plants to regulate the symbiosis with AM fungi, but the regulatory role of cytokinin (CK) is not well understood. Here, we used transgenic tobacco (Nicotiana tabacum) with a root-specific or constitutive expression of CK-degrading CKX genes and the corresponding wild-type to investigate whether a lowered content of CK in roots or in both roots and shoots influences the interaction with the AM fungus Rhizophagus irregularis. Our data indicates that shoot CK has a positive impact on AM fungal development in roots and on the root transcript level of an AM-responsive phosphate transporter gene (NtPT4). A reduced CK content in roots caused shoot and root growth depression following AM colonization, while neither the uptake of phosphorus or nitrogen nor the root transcript levels of NtPT4 were significantly affected. This suggests that root CK may restrict the C availability from the roots to the fungus thus averting parasitism by AM fungi. Taken together, our study indicates that shoot- and root-borne CK have distinct roles in AM symbiosis. We propose a model illustrating how plants may employ CK to regulate nutrient exchange with the ubiquitous AM fungi.

Shoot regeneration and embryogenesis in lily shoot tips cryopreserved by droplet vitrification

Science.gov (United States)

Shoot regeneration and embryogenesis were, for the first time, achieved directly in shoot tips of Lilium Oriental hybrid ‘Siberia’ following cryopreservation by droplet-vitrification. Shoot tips (2 mm in length) including 2-3 leaf primordia were excised from 4-week-old adventitious shoots directly r...

The correlation of the radiocaesium concentration of new shoots harvested in 2012 and old leaves, and new shoots harvested in 2011 grown in Kanagawa prefecture

International Nuclear Information System (INIS)

Shiraki, Yoshiya; Takeda, Hajime; Okamoto, Tamotsu; Kita, Nobuhiro

2013-01-01

We conducted this study to analyze the correlation between 137 Cs concentration of new shoots harvested in the first crop of tea in 2012, and new shoots harvested in the shuto-bancha in 2011 and old leaves harvested at the same time respectively. In the first crop of tea in 2012, the 137 Cs concentration of new shoots was related to that of old leaves, and the correlation of the coefficient was 0.663(p 137 Cs concentration(new shoots/old leaves) was related to the days until harvest of the first crop of tea in 2012, and the correlation coefficient was -0.771(p 137 Cs concentration was derived from the dilution effect due to growth and development of tea plants. Regression analysis was performed to forecast the 137 Cs concentration of the new shoots in the first crop of tea. The 137 Cs concentration of new shoots in the harvested first crop of tea(Y) was related to the 137 Cs concentration of old leaves harvested the previous winter(X). The correlation of the coefficient was 0.783(p 137 Cs concentration of new shoots of the first crop of tea in 2012 decreased about 1/6 to 1/25 compared with that of new shoots of the first crop of tea in 2011. (author)

PRODUCTION OF THE NEW ANTIMALARIAL DRUG ARTEMISININ IN SHOOT CULTURES OF ARTEMISIA-ANNUA L

NARCIS (Netherlands)

WOERDENBAG, HJ; LUERS, JFJ; VANUDEN, W; PRAS, N; MALINGRE, TM; ALFERMANN, AW

From aseptically grown Artemisia annua plantlets, shoot cultures were initiated. Using different concentrations of auxine, cytokinine and sucrose, a suitable culture medium was developed, with respect to the growth of the shoots and their artemisinin accumulation. Nitrate concentration and

Adventitious shoot regeneration from in vitro cultured leaves of guava (Psidium guava L.

Directory of Open Access Journals (Sweden)

Óscar Concepción Laffitte

2004-07-01

Full Text Available 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 like explant in all experiments. The best re-sult was reached with MS basal medium supplemented with 0.75 mg/L of 6-benzylaminopurine. Was de-monstrated that for the leaves with more multiplication subculture number and taken from lower part of shoot (older; the morfogenetic potential falls significantly (p60% and the largest number of shoot per regenerating leaf (>3 were obtained with several wounds carried out in f orm of jabs to the central nerve of leaves. This regeneration protocol constitutes an important tool that can be applied for future studies of genetic transformation in this species. Key words: Tissue culture, leaf explants, growth regulators, organogenesis, guava

Contrasting seasonal overlaps between primary and secondary growth are linked to wood anatomy in Mediterranean sub-shrubs.

Science.gov (United States)

Camarero, J J; Palacio, S; Montserrat-Martí, G

2013-09-01

Whole-plant approaches allow quantification of the temporal overlap between primary and secondary growth. If the amount of time available to grow is short, there may be a high temporal overlap between shoot growth and wood formation. We hypothesise that such overlap depends on the duration of the growing season and relates to wood anatomy. We evaluated wood anatomy, shoot longitudinal and radial growth rates, fine root production and the concentrations of non-structural carbohydrates (NSC) in the wood of six sub-shrub species growing in sites with contrasting climatic conditions (Lepidium subulatum, Linum suffruticosum, Salvia lavandulifolia, Satureja montana, Ononis fruticosa, Echinospartum horridum). Sub-shrub species living in sites with a short growing season displayed a high overlap between aboveground primary and secondary growth and formed wide vessels, whereas species from the warmest and driest sites presented the reverse characteristics. The highest overlap was linked to a rapid shoot extension and thickening through the enhanced hydraulic conductivity provided by wide vessels. The reductions in NSC concentrations when growth peaked were low or moderate, indicating that sub-shrubs accumulate NSC in excess, as do trees. The temporal overlap among primary and secondary growth in woody plants may be connected to the duration and rates of shoot and wood growth, which in turn depend on the vessel lumen area. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

Sirococcus Shoot Blight

Science.gov (United States)

Thomas H. Nicholls; Kathryn Robbins

1984-01-01

Sirococcus shoot blight, caused by the fungus Sirococcus strobilinus Preuss, affects conifers in the Northern United States and southern Canada. The fungus infects the new shoots; diseased seedlings and saplings are especially affected. In the United States, sirococcus shoot blight has become increasingly widespread since the early 1970's. When favorable...

PERBANDINGAN JUMP SHOOT DENGAN AWALAN DAN TANPA AWALAN TERHADAP PENINGKATAN KETEPATAN SHOOTING DALAM PERMAINAN BOLABASKET

OpenAIRE

I Gusti Ngurah Agung Cahya Prananta; N. Adiputra; I P G Adiatmika

2015-01-01

The effectiveness of  jump-shoot technique step jump shoot and still jump shoot in a game is still questionable,  because many different assumptions arise. One opinion stated that step jump shoot was more effective and the other stated that and still jump shoot was more efective. Therefore it is necessary to do research on the analysis of the results of step jump shoot and and still jump shoot to improve the accuracy of shooting in a basketball. The experimental research had been conducted on...

Effect of benzylaminopurine (BAP) pulsing on in vitro shoot ...

African Journals Online (AJOL)

user

2011-03-28

Mar 28, 2011 ... Research Cluster, Faculty of Science, University Malaya, 50603 Kuala Lumpur, Malaysia. Accepted 12 ... number of bud formation in shoot cultures of Musa acuminata cv. ... In tissue culture, plant growth regulators (PGR) are.

Shoot bending promotes flower bud formation by miRNA-mediated regulation in apple (Malus domestica Borkh.).

Science.gov (United States)

Xing, Libo; Zhang, Dong; Zhao, Caiping; Li, Youmei; Ma, Juanjuan; An, Na; Han, Mingyu

2016-02-01

Flower induction in apple (Malus domestica Borkh.) trees plays an important life cycle role, but young trees produce fewer and inferior quality flower buds. Therefore, shoot bending has become an important cultural practice, significantly promoting the capacity to develop more flower buds during the growing seasons. Additionally, microRNAs (miRNAs) play essential roles in plant growth, flower induction and stress responses. In this study, we identified miRNAs potentially involved in the regulation of bud growth, and flower induction and development, as well as in the response to shoot bending. Of the 195 miRNAs identified, 137 were novel miRNAs. The miRNA expression profiles revealed that the expression levels of 68 and 27 known miRNAs were down-regulated and up-regulated, respectively, in response to shoot bending, and that the 31 differentially expressed novel miRNAs between them formed five major clusters. Additionally, a complex regulatory network associated with auxin, cytokinin, abscisic acid (ABA) and gibberellic acid (GA) plays important roles in cell division, bud growth and flower induction, in which related miRNAs and targets mediated regulation. Among them, miR396, 160, 393, and their targets associated with AUX, miR159, 319, 164, and their targets associated with ABA and GA, and flowering-related miRNAs and genes, regulate bud growth and flower bud formation in response to shoot bending. Meanwhile, the flowering genes had significantly higher expression levels during shoot bending, suggesting that they are involved in this regulatory process. This study provides a framework for the future analysis of miRNAs associated with multiple hormones and their roles in the regulation of bud growth, and flower induction and formation in response to shoot bending in apple trees. © 2015 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Short-term UV-B radiation and ozone exposure effects on aromatic secondary metabolite accumulation and shoot growth of flavonoid-deficient Arabidopsis mutants

International Nuclear Information System (INIS)

Ormrod, D.P.; Landry, L.G.; Conklin, P.L.

1995-01-01

The presence of UV-absorptive substances in the epidermal cells of leaves is thought to protect mesophyll tissues from the harmful effects of UV-B radiation. We examined the influence of short-term UV-B exposures on UV-absorptive (330 nm) sinapates and flavonols, and on shoot growth of the Arabidopsis wild type ecotype Landsberg erecta and two mutants. 114 deficient in chalcone synthase, and 115, deficient in chalcone/flavonone isomerase. Sequential ozone exposures were used to determine the effects of oxidative stress The levels of sinapates and flavonols on a leaf fresh weight basis increased substantially in the wild type and sinapates increased in the 114 mutant in vegetative vegetative/reproductive transitional and reproductive stage plants in response to short-term (48h) UV-B radiation. When UV-B was discontinued the levels generally decreased lo pre-exposure levels after 48 h in vegetative/reproductive but not in reproductive plants. Exposure to ozone before or alter UV-B treatment did not consistently affect the levels of these UV-absorptive compounds. Dry matter accumulation was less affected by UV-B at the vegetative and reproductive stages than at the vegetative/reproductive stage. At the vegetative/reproductive stage, shoot growth of all 3 genotypes was retarded by UV-B. Growth was not retarded by short-term ozone exposure alone but when exposure to ozone followed UV-B exposure, growth was reduced in all genotypes. Leaf cupping appeared on 115 plants exposed to UV-B

EPICORMIC SHOOTS INDUCTION AND ROOTING CUTTINGS OF Calophyllum brasiliense

Directory of Open Access Journals (Sweden)

Dagma Kratz

2016-12-01

Full Text Available Calophyllum brasiliense is present in a wide natural distribution range in Brazil and its monopodial growth, with a rectilinear stem and a moderately dense timber has attracted the attention from the logging industry in recent decades. In the meantime, the lack of efficient rescue and vegetative propagation methods of adult plants has been a narrowing condition for the selection of superior genotypes in breeding programs of the species. Therefore, we evaluate epicormic shoots induction methods and the rooting cuttings of 14 year-old Calophyllum brasiliense trees. From this scope, three methods of epicormic shoots induction were evaluated: coppicing, girdling and partial girdling. We evaluate the number of produced sprouts and the percentage of sprouted trees at 06, 12 and 15 months’ after the experiment installation. Results have indicated the feasibility of Calophyllum brasiliense vegetative rescue by cuttings method using epicormic shoots induced by coppicing and girdling. In contrast, partial girdling was not effective in epicormic shoots emission. Concerning adventitious roots, the sprouting technique had no influence in the rooting of cuttings, showing variation among the different stock plants.

Growth and morphogenesis of shoot initials of Douglas fir, Pseudotsuga menziesii (Mirb.) Franco, in vitro

NARCIS (Netherlands)

Evers, P.W.

1984-01-01

An optimalized method of micropropagation of Douglas fir is described. Seasonal changes were found in optima for nitrate and sucrose in the medium and in the optimum for the light intensity during the culture of shoot initials. Differences in morphogenesis were obtained from shoot initials that had

Wall extensibility: its nature, measurement and relationship to plant cell growth

Science.gov (United States)

Cosgrove, D. J.

1993-01-01

Expansive growth of plant cells is controlled principally by processes that loosen the wall and enable it to expand irreversibly. The central role of wall relaxation for cell expansion is reviewed. The most common methods for assessing the extension properties of plant cell walls ( wall extensibility') are described, categorized and assessed critically. What emerges are three fundamentally different approaches which test growing cells for their ability (a) to enlarge at different values of turgor, (b) to induce wall relaxation, and (c) to deform elastically or plastically in response to an applied tensile force. Analogous methods with isolated walls are similarly reviewed. The results of these different assays are related to the nature of plant cell growth and pertinent biophysical theory. I argue that the extensibilities' measured by these assays are fundamentally different from one another and that some are more pertinent to growth than others.

In vitro regeneration of Salix nigra from adventitious shoots.

Science.gov (United States)

Lyyra, Satu; Lima, Amparo; Merkle, Scott A

2006-07-01

Black willow (Salix nigra Marsh.) is the largest and only commercially important willow species in North America. It is a candidate for phytoremediation of polluted soils because it is fast-growing and thrives on floodplains throughout eastern USA. Our objective was to develop a protocol for the in vitro regeneration of black willow plants that could serve as target material for gene transformation. Unexpanded inflorescence explants were excised from dormant buds collected from three source trees and cultured on woody plant medium (WPM) supplemented with one of: (1) 0.1 mg l(-1) thidiazuron (TDZ); (2) 0.5 mg l(-1) 6-benzoaminopurine (BAP); or (3) 1 mg l(-1) BAP. All plant growth regulator (PGR) treatments induced direct adventitious bud formation from the genotypes. The percentage of explants producing buds ranged from 20 to 92%, depending on genotype and treatment. Although most of the TDZ-treated inflorescences produced buds, these buds failed to elongate into shoots. Buds on explants treated with BAP elongated into shoots that were easily rooted in vitro and further established in potting mix in high humidity. The PGR treatments significantly affected shoot regeneration frequency (P < 0.01). The highest shoot regeneration frequency (36%) was achieved with Genotype 3 cultured on 0.5 mg l(-1) BAP. Mean number of shoots per explant varied from one to five. The ability of black willow inflorescences to produce adventitious shoots makes them potential targets for Agrobacterium-mediated transformation with heavy-metal-resistant genes for phytoremediation.

Mechanisms of waterlogging tolerance in wheat - a review of root and shoot physiology

DEFF Research Database (Denmark)

Herzog, Max; Striker, Gustavo G; Colmer, Timothy D

2016-01-01

:shoot ratio. Genotypes differ in seminal root anoxia tolerance, but mechanisms remain to be established; ethanol production rates do not explain anoxia tolerance. Root tip survival is short-term, and thereafter, seminal root re-growth upon re-aeration is limited. Genotypes differ in adventitious root numbers....... Although photosynthesis declines, sugars typically accumulate in shoots of waterlogged plants. Mn or Fe toxicity might occur in shoots of wheat on strongly acidic soils, but probably not more widely. Future breeding for waterlogging tolerance should focus on root internal aeration and better N...

PERBANDINGAN JUMP SHOOT DENGAN AWALAN DAN TANPA AWALAN TERHADAP PENINGKATAN KETEPATAN SHOOTING DALAM PERMAINAN BOLABASKET

Directory of Open Access Journals (Sweden)

I Gusti Ngurah Agung Cahya Prananta

2015-01-01

Full Text Available The effectiveness of  jump-shoot technique step jump shoot and still jump shoot in a game is still questionable,  because many different assumptions arise. One opinion stated that step jump shoot was more effective and the other stated that and still jump shoot was more efective. Therefore it is necessary to do research on the analysis of the results of step jump shoot and and still jump shoot to improve the accuracy of shooting in a basketball. The experimental research had been conducted on 20samples of people whowere selected randomly from the men's basketball club of the Faculty of Physical Educationand Health of Teacher Training Institute PGRI Bali. Samples were divided into two groups each  consisting of 10 people. Group I was given training step  jump shoot four sets of 10 reps  and Group II training still jump shoot four sets of 10 reps. The data before and after treatment were tested by SPSS computer program. The data were normally distributed and homogeneous so further tested using pairedt-test to compare the average values?? before and after training between each group, while the independent t-test was used to determine differences in mean values?? between the two groups. Paired t-test resulted the obtained data were significantly increased in both treatment groups p=0,001 in Group I and p=0,000 in Group II (p <0.05. Results of independent t-test found that both groups before training did not differ significantly p=0,926 (p>0.05 and after training both groups equally improve the accuracy of shooting because p=0,133 (p>0.05. It was concluded that botht raining improved the shooting accuracy and there was no difference between the effect of step jumps hoot and still jump shoot toward the shooting accuracy. It was suggested to improve the shooting accuracy in basketball used step jump shoot training and still jump shoot training four sets of 10 reps with a training frequency of 4 times a week for 6 weeks

76 FR 1339 - Pine Shoot Beetle; Additions to Quarantined Areas

Science.gov (United States)

2011-01-10

... Domestic Programs, PPQ, APHIS, 4700 River Road Unit 26, Riverdale, MD 20737-1231; (301) 734-5705... distorted growth in host trees. Large infestations of PSB typically kill most of the lateral shoots near the...

Effects of BAP and TIBA on Shoot Proliferation of Rosa hybrida L. cv. Full House in in vitro Culture

Directory of Open Access Journals (Sweden)

S. Hajian

2016-02-01

Full Text Available Micropropagation is a proper approach to rapid and large-scale propagation of rootstocks and rose cultivars for huge demand of flower market. Proliferation rate of shoot is decreased drastically following several subcultures. Growth regulators have remarkable effects on the key phase of proliferation in micropropagation of this popular crop. In this research the effects of BAP and antiauxin of TIBA on quality and quantity of developed shoots in Rosa hybrida cv. Full House were studied. BAP and TIBA were applied at three concentrations of 0, 2.2 and 8.8 µmol in proliferation phase of micropropagation. The experiment was conducted based on factorial and completely randomized design with four replications. After two months, the percentage of proliferated explants, survived main and lateral shoot number, length of the main and lateral shoots, number of green leaves on the shoots, the average number of shoots with chlorotic and necrotic leaves, the average axillary shoot base diameter, fresh weight of shoots and number of shoots with necrotic tip were recorded. Analysis of variance indicated that BAP was ineffective on the number of the main shoot green leaves and decreasing number of shoots with necrotic tip, but enhanced other traits. The concentration of 8.8 µmol of BAP had greater effect than 2.2 µmol of this growth regulator on mentioned traits. The higher concentration of TIBA resulted to more shoot with necrotic tip. This antiauxin had anegative impact on shoot fresh weight, but the other parameters were not significantly affected.

Microclonal Multiplication of wild Cherry (Prunus avium L.) from Shoot Tips and Root Sucker Buds

OpenAIRE

Pevalek-Kozlina, Branka; Michler, Charles H.; Jelaska, Sibila

1994-01-01

The effects of different combinations and concentrations of the growth regulators: 6-benzylaminopurine (BA), 6-furfurylaminopurine (KIN), N6- (2-isopentenyl) adenine (2iP), indole-3-butyric acid (IBA), indole-3-acetic acid (IAA) and a-naphthaleneacetic acid (NAA) on axillary shoot multiplication rates for wild cherry (Prunus avium L.) shoot explants were determined. Apical shoot tips and axillary buds from juvenile trees (5-year old) and from root suckers of mature trees (55-year old) were us...

Interactions between cadmium and other heavy metals in affecting the growth of lettuce (Lactuca sativa L. c. v. Webbs Wonderful) seedlings

Energy Technology Data Exchange (ETDEWEB)

Lepp, N.W.

1977-01-01

Changes in root and shoot extension of lettuce seedlings in relation to single or dual applications of heavy metal ions have been studied. When cadmium, copper, lead or nickel are applied singly, at concentrations of 10 ..mu..g/litre, significant reductions in root and shoot growth of the seedlings are apparent. Dual ion applications of 10 ..mu..g/litre cadmium with 10 ..mu..g/litre of any of the other elements produce no significant synergistic reduction in seedling growth. The responses observed are either additive or antagonistic, depending upon the metal treatment. The results are discussed in terms of their possible significance to heavy metal effects on plant growth. 14 references, 1 figure.

Photosynthesis of a scots pine shoot: the effect of shoot inclination on the photosynthetic response of a shoot subjected to direct radiation

International Nuclear Information System (INIS)

Oker-Blom, P.; Kellomaki, S.; Smolander, H.

1983-01-01

A set of photosynthetic responses of a Scots pine (Pinus sylvestris L.) shoot to light was derived from the shoot geometry and the photosynthetic response of a single needle. Computations showed that the shape of the photosynthesis light-curves varies substantially depending on the direction of radiation relative to the shoot position. Differences in the initial and maximum rates of photosynthesis were due to changes in the effective projection area and the irradiated fraction of the shoot, respectively

Radiocesium distribution in bamboo shoots after the Fukushima nuclear accident.

Directory of Open Access Journals (Sweden)

Takumi Higaki

Full Text Available The distribution of radiocesium was examined in bamboo shoots, Phyllostachys pubescens, collected from 10 sites located some 41 to 1140 km from the Fukushima Daiichi nuclear power plant, Japan, in the Spring of 2012, 1 year after the Fukushima nuclear accident. Maximum activity concentrations for radiocesium ¹³⁴Cs and ¹³⁷Cs in the edible bamboo shoot parts, 41 km away from the Fukushima Daiichi plant, were in excess of 15.3 and 21.8 kBq/kg (dry weight basis; 1.34 and 1.92 kBq/kg, fresh weight, respectively. In the radiocesium-contaminated samples, the radiocesium activities were higher in the inner tip parts, including the upper edible parts and the apical culm sheath, than in the hardened culm sheath and underground basal parts. The radiocesium/potassium ratios also tended to be higher in the inner tip parts. The radiocesium activities increased with bamboo shoot length in another bamboo species, Phyllostachys bambusoides, suggesting that radiocesium accumulated in the inner tip parts during growth of the shoots.

School Shootings and Student Performance

OpenAIRE

Panu Poutvaara; Olli Ropponen

2010-01-01

In this paper, we study how high school students reacted to the shocking news of a school shooting. The shooting coincided with national high-school matriculation exams. As there were exams both before and after the shooting, we can use a difference-in-differences analysis to uncover how the school shooting affected the test scores compared to previous years. We find that the average performance of young men declined due to the school shooting, whereas we do not observe a similar pattern for ...

Differential TOR activation and cell proliferation in Arabidopsis root and shoot apexes.

Science.gov (United States)

Li, Xiaojuan; Cai, Wenguo; Liu, Yanlin; Li, Hui; Fu, Liwen; Liu, Zengyu; Xu, Lin; Liu, Hongtao; Xu, Tongda; Xiong, Yan

2017-03-07

The developmental plasticity of plants relies on the remarkable ability of the meristems to integrate nutrient and energy availability with environmental signals. Meristems in root and shoot apexes share highly similar molecular players but are spatially separated by soil. Whether and how these two meristematic tissues have differential activation requirements for local nutrient, hormone, and environmental cues (e.g., light) remain enigmatic in photosynthetic plants. Here, we report that the activation of root and shoot apexes relies on distinct glucose and light signals. Glucose energy signaling is sufficient to activate target of rapamycin (TOR) kinase in root apexes. In contrast, both the glucose and light signals are required for TOR activation in shoot apexes. Strikingly, exogenously applied auxin is able to replace light to activate TOR in shoot apexes and promote true leaf development. A relatively low concentration of auxin in the shoot and high concentration of auxin in the root might be responsible for this distinctive light requirement in root and shoot apexes, because light is required to promote auxin biosynthesis in the shoot. Furthermore, we reveal that the small GTPase Rho-related protein 2 (ROP2) transduces light-auxin signal to activate TOR by direct interaction, which, in turn, promotes transcription factors E2Fa,b for activating cell cycle genes in shoot apexes. Consistently, constitutively activated ROP2 plants stimulate TOR in the shoot apex and cause true leaf development even without light. Together, our findings establish a pivotal hub role of TOR signaling in integrating different environmental signals to regulate distinct developmental transition and growth in the shoot and root.

Plant root and shoot dynamics during subsurface obstacle interaction

Science.gov (United States)

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

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

Simulating the partitioning of biomass and nitrogen between roots and shoot in crop and grass plants

NARCIS (Netherlands)

Yin, X.; Schapendonk, A.H.C.M.

2004-01-01

Quantification of the assimilate partitioning between roots and shoot has been one of the components that need improvement in crop growth models. In this study we derived two equations for root-shoot partitioning of biomass and nitrogen (N) that hold for crops grown under steady-state conditions.

From gene manipulation to forest establishment: shoot cultures of woody plants can be a central tool

Energy Technology Data Exchange (ETDEWEB)

McCown, B.H.

1985-05-01

Establishing germplasm of woody plants in microculture as shoot cultures has proved to be an effective method of overcoming many of the obstacles in working with these crops. Shoot cultures eliminate the changes associated with seasonal growth cycles and phase change and put large plants into a more manageable form. Well-established shoot cultures are central to successful clonal propagation systems for forest trees as well as to genetic improvement based on the use of cellular techniques such as protoplast manipulation. The physiological basis as to why tissues from shoot cultures are so readily manipulated is not well understood.

Assessment of carbon sources on in vitro shoot regeneration in tomato

International Nuclear Information System (INIS)

Shah, S.H.; Jan, S.A.

2014-01-01

An innovative approach for in vitro shoot regeneration by both direct and indirect means was developed in three tomato genotypes culturing hypocotyls and leaf discs explants on MS and N6 basal media fortified with various concentrations of carbon sources (sucrose and sorbitol) individually, accumulatively and also in amalgamation with various plant growth regulators. No response of in vitro shoot regeneration was recorded in all the genotypes by the individual application of carbon sources in both MS and N6 basal media. On the other hand, their accumulative effect rapidly enhanced the in vitro shoot regeneration frequency in all the genotypes. The highest shoot organogenesis frequency (100, 99.00 and 97.69%) was recorded in Rio Grande, Roma and Moneymaker, respectively on MS medium fortified with carbon sources (30: 30 g/l) culturing hypocotyls. Supplementation of sucrose: sorbitol (30: 30 g/l) in N6 medium along with different PGRs (0.1 mg/l IAA, 1.0 mg/l ZEA and 2.0 mg/l BAP) produced the highest shoot regeneration frequency (96.33, 92.69 and 88.74%) in Roma, Rio Grande and Moneymaker culturing leaf discs. Our findings suggest an alternative approach as hormone-free protocol for in vitro shoot regeneration in tomato that would save the resources with regard to hormonal costs and time. (author)

Growth, shoot phenology and physiology of diverse seed sources of black spruce: II 23-year-old field trees

Science.gov (United States)

Kurt H. Johnsen; John R. Seiler; John E. Major

1996-01-01

Four sources of 23-year-old black spruce (Picea mariana (Mill.) B.S.P.) from a provenance test at the Petawawa National Forestry Institute (46° N, 77°30¢ W) were assessed for height growth, shoot phenology and seasonal gas exchange. The provenances were designated 7000 (Yukon, 63°34¢ N, 135°55¢ W), 6979 (Alberta 52°22¢ N, 115°15¢ W), 6908 (Ontario, 48°59¢ N, 80°38¢ W)...

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

Science.gov (United States)

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

2007-10-01

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

Study on the growth and development of brinjal shoot and fruit borer ...

African Journals Online (AJOL)

Jane

2011-09-28

Sep 28, 2011 ... 2Department of Crop Science, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia. ... various aspects of the insect's life and activity with a view to evolving .... of brinjal shoot and fruit borer is still a difficult job. Many.

Opposite metabolic responses of shoots and roots to drought

Czech Academy of Sciences Publication Activity Database

Gargallo-Garriga, A.; Sardans, J.; Pérez-Trujillo, M.; Rivas-Ubach, A.; Oravec, Michal; Večeřová, Kristýna; Urban, Otmar; Jentsch, A.; Kreyling, J.; Beierkuhnlein, C.; Parella, T.; Penuelas, J.

2014-01-01

Roč. 4, č. 6829 (2014), s. 1-7 ISSN 2045-2322 Grant - others:AV ČR(CZ) M200871201 Institutional support: RVO:67179843 Keywords : shoot and roots * autotrophic and heterotrophic organs * environmental change * growth metabolism * water and nutirens Subject RIV: EH - Ecology, Behaviour Impact factor: 5.578, year: 2014

Adventitious shoot regeneration from leaf explants of the valuable ...

African Journals Online (AJOL)

Jane

2011-08-10

Aug 10, 2011 ... 2Department of Plant Biology and Plant Biotechnology, St. Joseph's College, Tiruchirappalli – 620 002, South India. Accepted 28 March, 2011 .... Effect of cytokinins (KN and BAP) alone or in combination with NAA on direct shoot bud regeneration from leaf explants of P. barbatus. Plant growth regulator ...

Assessment of silver nitrate on callus induction and in vitro shoot regeneration in tomato (solanum lycopersicum mill.)

International Nuclear Information System (INIS)

Shah, S.H.; Ali, S.; Jan, S.A.

2014-01-01

In vitro morphogenesis is greatly influenced by a gaseous plant growth regulator (ethylene). The effect of silver nitrate (AgNO/sub 3/) and different plant growth regulators were assessed on callus induction, In vitro shoot regeneration and multiple primordial shoots per explant in tomato. The maximum callus induction frequency was recorded culturing hypocotyls, while In vitro shoot regeneration frequency and the number of primordial shoots per explant were significantly higher when leaf discs were used as explants. The callus induction frequency was improved by the supplementation of 10-15 mg/l AgNO/sub 3/ in MS basal media along with 2.0 mg/l IAA, 2.5 mg/l BAP and yielded the highest callus induction frequency (91.33%) in cv. Rio Grande, followed by Roma (88.33%) and Moneymaker (82.66%). Similarly, the highest In vitro shoot regeneration frequency (96.66, 92.66 and 90%) was recorded in Rio Grande, Roma and Moneymaker on MS media fortified with 0.1 mg/l IAA, 1.0 mg/l ZEA and 2.0 mg/l BAP along with 8-10 mg/l AgNO/sub 3/. AgNO/sub 3/ also had promotive effect on induction of multiple shoots per explant. These findings indicate that ethylene is linked with the suppression of In vitro morphogenesis in tomato and AgNO3 interacts with ethylene and enhances callus induction and In vitro shoot regeneration in tomato. (author)

Zinc oxide nanoparticle exposure triggers different gene expression patterns in maize shoots and roots.

Science.gov (United States)

Xun, Hongwei; Ma, Xintong; Chen, Jing; Yang, Zhongzhou; Liu, Bao; Gao, Xiang; Li, Guo; Yu, Jiamiao; Wang, Li; Pang, Jinsong

2017-10-01

The potential impacts of environmentally accumulated zinc oxide nanoparticles (nZnOs) on plant growth have not been well studied. A transcriptome profile analysis of maize exposed to nZnOs showed that the genes in the shoots and roots responded differently. Although the number of differentially expressed genes (DEGs) in the roots was greater than that in the shoots, the number of up- or down-regulated genes in both the shoots and roots was similar. The enrichment of gene ontology (GO) terms was also significantly different in the shoots and roots. The "nitrogen compound metabolism" and "cellular component" terms were specifically and highly up-regulated in the nZnO-exposed roots, whereas the categories "cellular metabolic process", "primary metabolic process" and "secondary metabolic process" were down-regulated in the exposed roots only. Our results revealed the DEG response patterns in maize shoots and roots after nZnO exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

Monochromic radiation through light-emitting diode (LED positively augments in vitro shoot regeneration in Orchid (Dendrobium sonia

Directory of Open Access Journals (Sweden)

Vandita Billore

2017-07-01

Full Text Available Monochromatic lights emitted by light-emitting diodes (LEDs have generated great interest for efficient and controlled growth in vitro, especially of plants which are endangered or require specific intensity and wavelength of light. In the present study, we have evaluated the effect of monochromatic LEDs on in vitro morphogenesis: growth, proliferation of shoot cultures, and rooting of Dendrobium sonia. Different light sources viz. white LEDs (W, blue LEDs (B, yellow LEDs (Y and red LEDs (R were tested under photoperiod of 16 h of exposure and 8 h of dark. The frequency of morphogenesis depended on the wavelength of the applied monochromatic light. Higher wavelength monochromatic light (yellow light was observed to induce higher shoot proliferation (98%, early PLB (protocorm-like bodies formation, differentiation into green buds and shoot initiation as compared to red, blue and white light treatments. Yellow light also yielded higher number of shoots per explants (29 shoots/explant than red, blue and white light treatments. The results suggest that the monochromatic light sources stimulate morphogenic effects on in vitro culture of Dendrobium sonia, and that yellow light treatment can be used to enhance the efficiency of micropropagation.

Growing different Lactuca genotypes aeroponically within a tropical greenhouse – Cool rootzone temperatures decreased rootzone ethylene concentrations and increased shoot growth

Directory of Open Access Journals (Sweden)

Tsui Wei CHOONG

2016-09-01

Full Text Available Temperate crops cannot grow well in the tropics without rootzone cooling. As cooling increased production costs, this experiment aimed to study the growth of various Lactuca genotypes and propose possible ways of reducing these costs, without compromising productivity. A recombinant inbred line (RIL of lettuce and its parental lines (L. serriola and L. sativa ‘Salinas’ were grown aeroponically in a tropical greenhouse under 24 C cool (C or warm fluctuating 30-36 C ambient (A rootzone temperature (RZT. Their roots were misted with Netherlands standard nutrient solution for 1 min, at intervals of either 5 min (A5, C5 or 10 min (A10, C10 in attempting to reduce electricity consumption and production costs. Lower mortality and higher productivity were observed in all genotypes when grown in C-RZT. Higher shoot fresh weight was observed under C5 than C10, for the RIL and L. serriola. Since ‘Salinas’ had similar shoot fresh weight at both C-RZ treatments, this may indicate it is more sensitive to RZT than water availability. Under A-RZ treatments, higher carotenoid content, with correspondingly higher nonphotochemical quenching, was observed in A10 for the RIL and ‘Salinas’. Further, total chlorophyll content was also highest at this RZ treatment for the RIL though photochemical quenching was contrastingly the lowest. Cumulatively, productivity was compromised at A10 as the RIL seemed to prioritize photoprotection over efficiency in photosynthesis, under conditions of higher RZT and lower water availability. Generally, higher RZ ethylene concentrations accumulated in A10 and C10 than A5 and C5, respectively – probably due to spray frequency exerting a greater effect on RZ ethylene accumulation than RZT. In the C5 RZ treatment, lowest RZ ethylene concentration corresponded with highest shoot fresh weight. As such, further research on ethylene (insensitivity and water use efficiency could be conducted to identify Lactuca cultivars

Relationship between the shoot characteristics and plant resistance to vascular-streak dieback on cocoa

Directory of Open Access Journals (Sweden)

Agung Wahyu Soesilo

2014-12-01

Full Text Available Vascular-streak dieback (Oncobasidium theobromae is a serious disease on cocoa damaging the vegetative tissue especially on the branches and leaves. This research was aimed to identify the relationship between characteristics of sprouting ability and VSD resistance to confirm the response of cocoa to pruning treatment on VSD control and developing criteria for selection. Trial was carried out at Kaliwining Experimental Station of ICCRI, a VSD-endemic area by using 668 plants of hybrid populayion which were derivated from intercrossing among seven clones performing different response to VSD. The resistance was evaluated by scoring the plant damage with the scale of 0-6 on drought season in the year of 2009 and 2011. The characteristics of sprouting ability was assessed by recording the pruned trees for the variables of the number of re-growth shoot, shoot height, number of new shoot per pruned branches, shoot diameter and number of leaves per shoot. It was analyzed that the variables of the number of shoot per pruned branches, shoot diameter, shoot height and number of leaves per shoot were not significantly correlated to the score of VSD damage. Grouping of the resistance also performed similar results whereas mean of the sprouting variables were not different among group but the percentage of sprouted branches tend to be higher with the higher of the resistance (lower score. This result confirmed any mechanism of tolerance on VSD resistance by accelerating shoot rejuvenation on resistant plant. Key words : vascular-streak diaback, cocoa, resistance, characteristics of sprouting

Propagation of pineapple by shoot tip culture

International Nuclear Information System (INIS)

Almobasher, H. A. A.; Osman, M. G.; Said, A. E.

2009-01-01

This study was conducted with the objective of modifying the composition of MS medium for the clonal propagation of pineapple using shoot tips of Smooth Cayenne cultivar. Modification were made on various medium components. Results showed that both MS salts at the full or half strength were optimal, and there was on significant difference between them. Sucrose concentrations of 3% and 6% were better than other concentrations tested for growth and development of plant lets. The cultures responded positively to the increase of adenine sulfate and 80 mg/1 was the optimal. As for the additions of NAA and BA , alone or in combinations, the best results were recorded with the combination of NAA at 0.01 mg/1, and BA at 3.0 mg/1 where the largest number of shoots was obtained. Better explants performance was achieved on liquid medium with cotton support compared to solid medium. (Author)

Giant growth-hormone secreting pituitary tumour with etracranial extension

Energy Technology Data Exchange (ETDEWEB)

Ip Taipang; Chan Fuluk; Kung Annie Waichee; Lam Karen Siuling [Univ. of Hong Kong, Queen Mary Hospital (Hong Kong). Depts. of Medicine and Diagnostic Radiology

1996-02-01

A 19 year old female patient with typical features of acromegaly was found to have an extensive pituitary tumour with suprasellar, lateral and inferior extensions. Magnetic resonance imaging (MRI) also showed a portion of the tumour extending from the right cavernous sinus through the foramen ovale to become extracranial. Serum growth hormone (GH) was 52.6 mU/L basally and remained elevated after oral glucose, confirming the diagnosis of acromegaly. Treatment with the long-acting somatostatin analogue, octreotide, for 6 months led to a 30% reduction in tumour volume of the intracranial portion but no effect on the extracranial and sphenoidal extensions. She was subsequently treated with trans-sphenoidal surgery followed by external irradiation. The possibility of perineural spread of the tumour was considered. 9 refs., 1 tab., 1 fig.

Giant growth-hormone secreting pituitary tumour with etracranial extension

International Nuclear Information System (INIS)

Ip Taipang; Chan Fuluk; Kung Annie Waichee; Lam Karen Siuling

1996-01-01

A 19 year old female patient with typical features of acromegaly was found to have an extensive pituitary tumour with suprasellar, lateral and inferior extensions. Magnetic resonance imaging (MRI) also showed a portion of the tumour extending from the right cavernous sinus through the foramen ovale to become extracranial. Serum growth hormone (GH) was 52.6 mU/L basally and remained elevated after oral glucose, confirming the diagnosis of acromegaly. Treatment with the long-acting somatostatin analogue, octreotide, for 6 months led to a 30% reduction in tumour volume of the intracranial portion but no effect on the extracranial and sphenoidal extensions. She was subsequently treated with trans-sphenoidal surgery followed by external irradiation. The possibility of perineural spread of the tumour was considered. 9 refs., 1 tab., 1 fig

Altitudinal variations of ground tissue and xylem tissue in terminal shoot of woody species: implications for treeline formation.

Science.gov (United States)

Chen, Hong; Wang, Haiyang; Liu, Yanfang; Dong, Li

2013-01-01

1. The terminal shoot (or current-year shoot), as one of the most active parts on a woody plant, is a basic unit determining plant height and is potentially influenced by a variety of environmental factors. It has been predicted that tissues amount and their allocation in plant stems may play a critical role in determining plant size in alpine regions. The primary structure in terminal shoots is a key to our understanding treeline formation. The existing theories on treeline formation, however, are still largely lacking of evidence at the species level, much less from anatomy for the terminal shoot. 2. The primary structures within terminal shoot were measured quantitatively for 100 species from four elevation zones along the eastern slope of Gongga Mountain, southwestern China; one group was sampled from above the treeline. An allometric approach was employed to examine scaling relationships interspecifically, and a principal components analysis (PCA) was performed to test the relation among primary xylem, ground tissue, species growth form and altitude. 3. The results showed that xylem tissue size was closely correlated with ground tissue size isometrically across species, while undergoing significant y- or/and x-intercept shift in response to altitudinal belts. Further, a conspicuous characteristic of terminal shoot was its allocation of contrasting tissues between primary xylem and ground tissues with increasing elevation. The result of the PCA showed correlations between anatomical variation, species growth form/height classes and environment. 4. The current study presents a comparative assessment of the allocation of tissue in terminal shoot across phylogenically and ecologically diverse species, and analyzes tissue, function and climate associations with plant growth forms and height classes among species. The interspecific connection between primary xylem ratio and plant size along an elevation gradient suggests the importance of primary xylem in explaining

Altitudinal variations of ground tissue and xylem tissue in terminal shoot of woody species: implications for treeline formation.

Directory of Open Access Journals (Sweden)

Hong Chen

Full Text Available 1. The terminal shoot (or current-year shoot, as one of the most active parts on a woody plant, is a basic unit determining plant height and is potentially influenced by a variety of environmental factors. It has been predicted that tissues amount and their allocation in plant stems may play a critical role in determining plant size in alpine regions. The primary structure in terminal shoots is a key to our understanding treeline formation. The existing theories on treeline formation, however, are still largely lacking of evidence at the species level, much less from anatomy for the terminal shoot. 2. The primary structures within terminal shoot were measured quantitatively for 100 species from four elevation zones along the eastern slope of Gongga Mountain, southwestern China; one group was sampled from above the treeline. An allometric approach was employed to examine scaling relationships interspecifically, and a principal components analysis (PCA was performed to test the relation among primary xylem, ground tissue, species growth form and altitude. 3. The results showed that xylem tissue size was closely correlated with ground tissue size isometrically across species, while undergoing significant y- or/and x-intercept shift in response to altitudinal belts. Further, a conspicuous characteristic of terminal shoot was its allocation of contrasting tissues between primary xylem and ground tissues with increasing elevation. The result of the PCA showed correlations between anatomical variation, species growth form/height classes and environment. 4. The current study presents a comparative assessment of the allocation of tissue in terminal shoot across phylogenically and ecologically diverse species, and analyzes tissue, function and climate associations with plant growth forms and height classes among species. The interspecific connection between primary xylem ratio and plant size along an elevation gradient suggests the importance of primary

Effects of irradiation on physicochemical and sensory qualities of fermented shoot tip of sweet potato

International Nuclear Information System (INIS)

Cui Li; Liu Chunquan; Li Dajing; Song Jiangfeng; Jiang Ning; Liu Chunju; Wu Haihong; Zhu Danyu

2011-01-01

The effect of irradiation on sensory quality, physicochemical and functional prosperities of fermented shoot tips of sweet potatoes were studied. The results showed that total content of free amino acids in fermented shoot tips of sweet potato were not influenced at 4 kGy irradiation, but increased at 6 kGy. Total content of organic acids in shoot tips were not influenced by 2 ∼ 6 kGy of irradiation. The total viable cells of the tips was reduced from 7.35 to 4.67 log CFU/g at 2 kGy irradiation, and no growth of total viable cells was observed at 4 and 6 kGy irradiated fermented shoot tips. It is recommended that 4 kGy was the endurance irradiation dose for fermented shoot tips of sweet potato to ensure the maximum retention of taste quality and health-relevant functionality. (authors)

Violence and school shootings.

Science.gov (United States)

Flannery, Daniel J; Modzeleski, William; Kretschmar, Jeff M

2013-01-01

Multiple-homicide school shootings are rare events, but when they happen they significantly impact individuals, the school and the community. We focus on multiple-homicide incidents and identified mental health issues of shooters. To date, studies of school shootings have concluded that no reliable profile of a shooter exists, so risk should be assessed using comprehensive threat assessment protocols. Existing studies primarily utilize retrospective case histories or media accounts. The field requires more empirical and systematic research on all types of school shootings including single victim incidents, those that result in injury but not death and those that are successfully averted. We discuss current policies and practices related to school shootings and the role of mental health professionals in assessing risk and supporting surviving victims.

Transcript profiling of cytokinin action in Arabidopsis roots and shoots discovers largely similar but also organ-specific responses

Directory of Open Access Journals (Sweden)

Brenner Wolfram G

2012-07-01

Full Text Available Abstract Background The plant hormone cytokinin regulates growth and development of roots and shoots in opposite ways. In shoots it is a positive growth regulator whereas it inhibits growth in roots. It may be assumed that organ-specific regulation of gene expression is involved in these differential activities, but little is known about it. To get more insight into the transcriptional events triggered by cytokinin in roots and shoots, we studied genome-wide gene expression in cytokinin-treated and cytokinin-deficient roots and shoots. Results It was found by principal component analysis of the transcriptomic data that the immediate-early response to a cytokinin stimulus differs from the later response, and that the transcriptome of cytokinin-deficient plants is different from both the early and the late cytokinin induction response. A higher cytokinin status in the roots activated the expression of numerous genes normally expressed predominantly in the shoot, while a lower cytokinin status in the shoot reduced the expression of genes normally more active in the shoot to a more root-like level. This shift predominantly affected nuclear genes encoding plastid proteins. An organ-specific regulation was assigned to a number of genes previously known to react to a cytokinin signal, including root-specificity for the cytokinin hydroxylase gene CYP735A2 and shoot specificity for the cell cycle regulator gene CDKA;1. Numerous cytokinin-regulated genes were newly discovered or confirmed, including the meristem regulator genes SHEPHERD and CLAVATA1, auxin-related genes (IAA7, IAA13, AXR1, PIN2, PID, several genes involved in brassinosteroid (CYP710A1, CYP710A2, DIM/DWF and flavonol (MYB12, CHS, FLS1 synthesis, various transporter genes (e.g. HKT1, numerous members of the AP2/ERF transcription factor gene family, genes involved in light signalling (PhyA, COP1, SPA1, and more than 80 ribosomal genes. However, contrasting with the fundamental difference of

PEMBELAJARAN LAY UP SHOOT MENGGUNAKAN MEDIA AUDIO VISUAL BASIC LAY UP SHOOT UNTUK MENINGKATKAN HASILBELAJAR LAY UP SHOOT PADA SISWA KELAS VIIIA SMP KANISIUS PATI TAHUN 2013/2014

Directory of Open Access Journals (Sweden)

Frendy Nurochwan Febryanto

2015-01-01

Full Text Available The purpose of this study was to determine the learning lay up shoot using basic audiovisual media shoot lay ups can improve learning outcomes shoot lay ups in class VIIIA Starch Canisius junior year 2013/2014 . This study uses Classroom Action Research ( CAR. The technique of collecting data through observation and assessment of learning outcomes shoot basketball lay up. Data analysis techniques used in this research is descriptive . At the end of the first cycle activity of teachers in teaching basic techniques lay up shoot using audio-visual media reaches 76.19%, whereas at the end of the first cycle of student activity during the learning process lay up shoot using audio-visualmediareaches78.57%. At the end of the second cycle of activity of teachers in teaching basic techniques lay up shoot using audio-visual media reaches 85.71%, whereas at the end of the second cycle of activity of students during the learning process lay up shoot using audio-visual media reaches 92.86%. Based on the results of the study it can be concluded that learning the lay-up shoot using basic audiovisual media shoot lay ups can improve student learning outcomes at Canisius junior class VIIIA Pati year 2013/2014.

Adolescent mass shootings: developmental considerations in light of the Sandy Hook shooting.

Science.gov (United States)

Rice, Timothy R; Hoffman, Leon

2015-05-01

Adolescent mass shootings are a special subset of mass killings, which continue despite significant preventative public health efforts. It is often held that these individuals have few salient warning signs that could have been identified. This piece proposes that mass shootings committed by adolescent and post-adolescent young males must be understood from a developmental perspective. The hypothesis proposed in this paper is that such killings occur as the result of the adolescent's frustrated effort to progress along normative development. The goal of normative separation from maternal figures by the boy is presented as a potential risk factor when this goal is thwarted. Childhood case material from the perpetrator of a recent adolescent mass shooting, the Sandy Hook shooting, is discussed as an illustration of this hypothesis. Implications for public health measures and for individualized treatment are presented and developed.

Shoot Organogenesis and Plant Regeneration from Leaf Explants of Lysionotus serratus D. Don

Directory of Open Access Journals (Sweden)

Qiansheng Li

2013-01-01

Full Text Available The gesneriaceous perennial plant, Lysionotus serratus, has been used in traditional Chinese medicine. It also has a great development potential as an ornamental plant with its attractive foliage and beautiful flowers. An efficient propagation and regeneration system via direct shoot organogenesis from leaf explant was established in this study. High active cytokinin (6-benzyladenine (BA or thidiazuron (TDZ was effective for direct organogenesis of initial induction. Murashige and Skoog (MS growth media containing 0.5 mg L−1 BA alone or with combination of 0.1 mg L−1  α-Naphthaleneacetic acid (NAA were the most effective for shoot proliferation. High BA concentration (1.0 mg L−1 in the media caused high percentage of vitrified shoots though they introduced high shoot proliferation rate. Histological observation indicated that adventitious shoot regeneration on the medium containing 0.5 mg L−1 BA alone occurred directly from leaf epidermal cells without callus formation. Regenerated shoots rooted well on medium containing half-strength MS medium with 0.5 mg L−1 indole-3-butyric acid (IBA and indole-3-acetic acid (IAA, and the plantlets successfully acclimatized and grew vigorously in the greenhouse with a 94.2% and 92.1% survival rate.

Changes of Root Hydraulic Conductivity and Root/Shoot Ratio of Durum Wheat and Barley in Relation to Nitrogen Availability and Mercury Exposure

Directory of Open Access Journals (Sweden)

Celestino Ruggiero

2007-09-01

Full Text Available The aim of this research was to verify, on whole plant level and during all the plant cycle, the hypothesis that nitrogen deficiency reduces root hydraulic conductivity through the water channels (aquaporins activity, and that the plant reacts by changing root/shoot ratio. Root hydraulic conductivity, plant growth, root/shoot ratio and plant water status were assessed for durum wheat (Triticum durum Desf. and barley (Hordeum vulgare L., as influenced by nitrogen availability and HgCl2 treatment. On both species during the plant cycle, nitrogen deficiency induced lower root hydraulic conductivity (-49 and -66% respectively for barley and wheat and lower plant growth. On wheat was also observed cycle delay, lower plant nitrogen content, but not lower leaf turgor pressure and epidermic cell dimension. The lower plant growth was due to lower plant dimension and lower tillering. Root /shoot ratio was always higher for nitrogen stressed plants, whether on dry matter or on surface basis. This was due to lower effect of nitrogen stress on root growth than on shoot growth. On wheat HgCl2 treatment determined lower plant growth, and more than nitrogen stress, cycle delay and higher root/shoot ratio. The mercury, also, induced leaf rolling, lower turgor pressure, lower NAR, higher root cell wall lignification and lower epidermic cell number per surface unity. In nitrogen fertilized plants root hydraulic conductivity was always reduced by HgCl2 treatment (-61 and 38%, respectively for wheat and barley, but in nitrogen unfertilized plants this effect was observed only during the first plant stages. This effect was higher during shooting and caryopsis formation, lower during tillering. It is concluded that barley and durum wheat react to nitrogen deficiency and HgCl2 treatment by increasing the root/shoot ratio, to compensate water stress due to lower water root conductivity probably induced by lower aquaporin synthesis or inactivation. However, this

Changes of Root Hydraulic Conductivity and Root/Shoot Ratio of Durum Wheat and Barley in Relation to Nitrogen Availability and Mercury Exposure

Directory of Open Access Journals (Sweden)

Giovanna Angelino

2011-02-01

Full Text Available The aim of this research was to verify, on whole plant level and during all the plant cycle, the hypothesis that nitrogen deficiency reduces root hydraulic conductivity through the water channels (aquaporins activity, and that the plant reacts by changing root/shoot ratio. Root hydraulic conductivity, plant growth, root/shoot ratio and plant water status were assessed for durum wheat (Triticum durum Desf. and barley (Hordeum vulgare L., as influenced by nitrogen availability and HgCl2 treatment. On both species during the plant cycle, nitrogen deficiency induced lower root hydraulic conductivity (-49 and -66% respectively for barley and wheat and lower plant growth. On wheat was also observed cycle delay, lower plant nitrogen content, but not lower leaf turgor pressure and epidermic cell dimension. The lower plant growth was due to lower plant dimension and lower tillering. Root /shoot ratio was always higher for nitrogen stressed plants, whether on dry matter or on surface basis. This was due to lower effect of nitrogen stress on root growth than on shoot growth. On wheat HgCl2 treatment determined lower plant growth, and more than nitrogen stress, cycle delay and higher root/shoot ratio. The mercury, also, induced leaf rolling, lower turgor pressure, lower NAR, higher root cell wall lignification and lower epidermic cell number per surface unity. In nitrogen fertilized plants root hydraulic conductivity was always reduced by HgCl2 treatment (-61 and 38%, respectively for wheat and barley, but in nitrogen unfertilized plants this effect was observed only during the first plant stages. This effect was higher during shooting and caryopsis formation, lower during tillering. It is concluded that barley and durum wheat react to nitrogen deficiency and HgCl2 treatment by increasing the root/shoot ratio, to compensate water stress due to lower water root conductivity probably induced by lower aquaporin synthesis or inactivation. However, this

Methylation-sensitive amplification polymorphism in date palms (Phoenix dactylifera L.) and their off-shoots.

Science.gov (United States)

Fang, J-G; Chao, C T

2007-07-01

DNA methylation plays an important role in the regulation of gene expression in eukaryotes. In this study, the extent and patterns of DNA methylation were assessed in date palm mother-plants and their off-shoots using the methylation-sensitive amplified polymorphism (MSAP) technique. Three types of bands were generated using 12 pairs of primers. Type I were present in both ECOR I + HPA II and ECOR I + MSP I lanes; type II were present in ECOR I + HPA II lanes, but not in ECOR I + MSP I lanes; and type III bands were present in ECOR I + MSP I lanes, but not in ECOR I + HPA II lanes. The total numbers of these three types of bands were 782, 55, and 34, respectively. Among these three types of bands, the polymorphic bands were, respectively, 37, 10, and 0. The distribution of polymorphic bands among mother-plants and off-shoots suggests the methylation variation was present in both the mother-plants and off-shoots. Forty- four out of these 47 polymorphic bands show clear difference between mother-plant and off-shoots: 38 were present only in off-shoots and 6 in both mother-plants and off-shoots. Compared to methylation status in mother-plants, the methylation variation during off-shoot growth of date palm can be characterized as a process involving primarily de-methylation. Hypomethylation of DNA in off-shoots, compared with mother-plants, reflects the marked expression of this molecular feature, which may be related to gene expression during off-shoot development. The methylation or de-methylation status of specific loci in the mother-plants and their off-shoots were probably random events.

Effect of X-Rays on Growth Rate of Rose Shoot Cultures and the Ability of Isolated Protoplasts to Form Cell Colonies

International Nuclear Information System (INIS)

Moustafa, R. A. K.

2004-01-01

The popularity of rose as a garden plant, allied with its use in the production of cut flowers and also as a source of aromatic rose oils, make it one of the most important ornamental crops. Roses, however, have suffered from a narrow genetic base to which only few species have contributed significantly. In vitro culture of plants might facilitate the improvement of rose via the exploitation of somaclonal variation to generate new genetic variability and selection within the variation for desirable traits. The application of mutagens for in vitro cultures, in addition to the induced mutations, may lead to increase the somaclonal variation, thus providing additional variation for selection. On the other hand, plant protoplasts offer exciting possibilities to establish in vitro selection programs based on single cells. Induced variation in isolated protoplasts using mutagen agents may be one mean to select useful mutants. Thus the present experiments were conducted to determine the effect of X-rays on shoot cultures and the isolated protoplasts of rose (Rosa sp.). The materials consisted of the three rose varieties Rosa wichuriana, Paricer charm and Heckenzauber.The applied doses were 0, 10, 20, 30, 40, 50 and 60 Gy. Obtained results indicated that the genotypes differed in their sensitivity to X-rays. Rosa wichuriana seemed to be the most sensitive variety to radiation, where a dose of 20 Gy caused approximately 50% reduction in growth rate of shoot cultures, while the same dose decreased the growth rate of Paricer charm only by 25% and did not affect the growth of Heckenzauber. Results also revealed that the ability of irradiated protoplasts to form cell colonies increased when a dose of 10 Gy was performed. Doses higher than that level caused gradual decreasing in the forming of cell colonies, but however, the protoplasts could form colonies even when a dose of 60 Gy was applied. (Author)

The effect of tomato juices and bean sprout extracts on vitro shoot regeneration of Physalis angulata L.

Science.gov (United States)

Mastuti, Retno; Munawarti, Aminatun; Rosyidah, Mufidatur

2017-11-01

Physalis angulata L. (Ciplukan) which belongs to Solanaceae is an important medicinal plant. In vitro culture medium contains carbon source, inorganic substance, vitamins, and plant growth regulators. However, organic growth supplements have frequently been added to improve regeneration capability of explants. This study was conducted to observe the effect of tomato juices and extract bean sprout on shoot regeneration and multiplication of in vitro nodal explants. The explants were cultured on MS basal medium + 6-benzyl amino purine (BAP) 2 mg/L + indole-3-acetic acid (IAA) 0.05 mg/L with and without organic supplements. Tomato juices (T) 5, 7.5 and 10% or bean sprout extract (B) 1.25, 2.5, and 3.75% were added as natural organic supplements. Almost all explants have produced shoots one week after culture. After six weeks of culture maximum shoot number (12.5±3.9) was produced in medium MS + T5 while maximum shoot length (10.7 ± 0.7 cm) was obtained in medium MS + T 7.5. Medium T tends to produce more shoots than the medium B and medium control. This result indicates the potential of natural organic supplements for supporting Ciplukan propagation through in vitro culture.

In-vitro morphogenesis of corn (Zea mays L.) : I. Differentiation of multiple shoot clumps and somatic embryos from shoot tips.

Science.gov (United States)

Zhong, H; Srinivasan, C; Sticklen, M B

1992-07-01

In-vitro methods have been developed to regenerate clumps of multiple shoots and somatic embryos at high frequency from shoot tips of aseptically-grown seedlings as well as from shoot apices of precociously-germinated immature zygotic embryos of corn (Zea mays L.). About 500 shoots were produced from a shoot tip after eight weeks of culture (primary culture and one subculture of four weeks) in darkness on Murashige and Skoog basal medium (MS) supplemented with 500 mg/L casein hydrolysate (CH) and 9 μM N(6)-benzyladenine (BA). In this medium, shoots formed in shoot tips as tightly packed "multiple shoot clumps" (MSC), which were composed of some axillary shoots and many adventitious shoots. When the shoot tips were cultured on MS medium containing 500 mg/L CH, 9 μM BA and 2.25 μM 2,4-dichlorophenoxyacetic acid (2,4-D), most of the shoots in the clumps were adventitious in origin. Similar shoot tips cultured on MS medium containing 500 mg/L CH, 4.5 μM BA and 2.25 μM 2,4-D regenerated many somatic embryos within eight weeks of culture. Somatic embryos were produced either directly from the shoot apical meristems or from calli derived from the shoots apices. Both the MSC and the embryos produced normal shoots on MS medium containing 2.25 μM BA and 1.8 μM indole-3-butyric acid (IBA). These shoots were rooted on MS medium containing 3.6 μM IBA, and fertile corn plants were grown in the greenhouse. The sweet-corn genotype, Honey N Pearl, was used for the experiments described above, but shoot-tip cultures from all of 19 other corn genotypes tested also formed MSC on MS medium containing 500 mg/L CH and 9 μM BA.

Current perspectives on shoot branching regulation

Directory of Open Access Journals (Sweden)

Cunquan YUAN,Lin XI,Yaping KOU,Yu ZHAO,Liangjun ZHAO

2015-03-01

Full Text Available Shoot branching is regulated by the complex interactions among hormones, development, and environmental factors. Recent studies into the regulatory mecha-nisms of shoot branching have focused on strigolactones, which is a new area of investigation in shoot branching regulation. Elucidation of the function of the D53 gene has allowed exploration of detailed mechanisms of action of strigolactones in regulating shoot branching. In addition, the recent discovery that sucrose is key for axillary bud release has challenged the established auxin theory, in which auxin is the principal agent in the control of apical dominance. These developments increase our understan-ding of branching control and indicate that regulation of shoot branching involves a complex network. Here, we first summarize advances in the systematic regulatory network of plant shoot branching based on current information. Then we describe recent developments in the synthesis and signal transduction of strigolactones. Based on these considerations, we further summarize the plant shoot branching regulatory network, including long distance systemic signals and local gene activity mediated by strigolactones following perception of external envi-ronmental signals, such as shading, in order to provide a comprehensive overview of plant shoot branching.

Growth patterns and annual growth cycle of Acacia karroo Hayne in ...

African Journals Online (AJOL)

... karroo; alice; botany; compensatory growth; condition; development; eastern cape; emergence; environmental conditions; field study; growth cycle; growth initiation; growth patterns; growth strategy; leaf growth; plant growth; savanna; shoot growth; soil depth; soil moisture; south africa; university of fort hare; water stress ...

Estudio comparativo del crecimiento y la ramificación de brotes anuales en dos especies de Nothofagus (Nothofagaceae y en híbridos inter-específicos Comparative study of annual shoot growth and branching in two species of Nothofagus (Nothofagaceae and inter-specific hybrids

Directory of Open Access Journals (Sweden)

Cristian Torres

2009-12-01

Full Text Available Las ramas principales y secundarias se diferencian en mayor o menor medida según las especies, lo cual puede observarse en base al crecimiento primario de los brotes que las originan. En ejemplares de vivero juveniles-adultos de Nothofagus obliqua, N. nervosa e híbridos entre ambas especies, se compararon la dinámica de alargamiento, el tamaño y la morfología de dos brotes distales de ramas principales: uno que continúa el alargamiento de la rama principal y el otro que inicia una rama secundaria. En N. alpina y en híbridos, los dos brotes más distales se diferencian más que en N. obliqua. A pesar de la homogeneidad ambiental en el vivero y el origen geográfico común para los ejemplares de N. nervosa y los híbridos, hubieron diferencias fenológicas y morfológicas entre estas entidades. La duración y tasa de alargamiento y la longitud final de los brotes fueron altamente variables en cada entidad. Las variaciones entre entidades en la diferenciación de ejes podrían indicar diferencias en sus capacidades de uso del espacio circundante. La diferenciación entre ramas principales y secundarias se iniciaría en el estado de yema. La variación intra-específica fenológica y morfológica es útil para programas de selección artificial de individuos.Main and secondary branches are more or less differentiated according to the species and this could be observed during the primary growth of the shoots that produce them. In young-adult trees of Nothofagus obliqua, N. nervosa and hybrids between them growing in a common garden, growth dynamics, size and morphology were compared between two distal shoots produced by main branches: one of these shoots continued the extension of the main branch whereas the other initiated a secondary branch. The two distal shoots differed from each other more notably in N. nervosa and in the hybrids than in N. obliqua. Despite the environmental homogeneities at the nursery and the common geographic origin of

[Identifying transcription factors involved in Arabidopsis adventious shoot regeneration by RNA-Seq technology].

Science.gov (United States)

Wang, Xingchun; Chen, Zhao; Fan, Juan; He, Miaomiao; Han, Yuanhuai; Yang, Zhirong

2015-04-01

Transcriptional regulation is one of the major regulations in plant adventious shoot regeneration, but the exact mechanism remains unclear. In our study, the RNA-seq technology based on the IlluminaHiSeq 2000 sequencing platform was used to identify differentially expressed transcription factor (TF) encoding genes during callus formation stage and adventious shoot regeneration stage between wild type and adventious shoot formation defective mutant be1-3 and during the transition from dedifferentiation to redifferentiation stage in wildtype WS. Results show that 155 TFs were differentially expressed between be1-3 mutant and wild type during callus formation, of which 97 genes were up-regulated, and 58 genes were down-regulated; and that 68 genes were differentially expressed during redifferentiation stage, with 40 genes up-regulated and 28 genes down-regulated; whereas at the transition stage from dedifferentiation to redifferention in WS wild type explants, a total of 231 differentially expressed TF genes were identified, including 160 up-regualted genes and 71 down-regulated genes. Among these TF genes, the adventious shoot related transcription factor 1 (ART1) gene encoding a MYB-related (v-myb avian myeloblastosis viral oncogene homolog) TF, was up-regulated 3 217 folds, and was the highest up-regulated gene during be1-3 callus formation. Over expression of the ART1 gene caused defects in callus formation and shoot regeneration and inhibited seedling growth, indicating that the ART1 gene is a negative regulator of callus formation and shoot regeneration. This work not only enriches our knowledge about the transcriptional regulation mechanism of adventious shoot regeneration, but also provides valuable information on candidate TF genes associated with adventious shoot regeneration for future research.

Shoot regeneration from cotyledonary leaf explants of jatropha curcas: A biodiesel plant

KAUST Repository

Kumar, Nitish Chandramohana

2010-03-07

A simple, high frequency, and reproducible method for plant regeneration through direct organogenesis from cotyledonary leaf explants of Jatropha curcas was developed using Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ) or 6-benzyl aminopurine (BAP). Medium containing TDZ has greater influence on regeneration as compared to BAP. The induced shoot buds were transferred to MS medium containing 10 lM kinetin (Kn), 4.5 lM BAP, and 5.5 lM a-naphthaleneacetic acid (NAA) for shoot proliferation. The proliferated shoots could be elongated on MS medium supplemented with different concentrations and combinations of BAP, indole-3-acetic acid (IAA), NAA, and indole-3-butyric acid (IBA). MS medium with 2.25 lM BAP and 8.5 lM IAA was found to be the best combination for shoot elongation. However, significant differences in plant regeneration and shoot elongation were observed among the genotypes studied. Rooting was achieved when the basal cut end of elongated shoots were dipped in half strength MS liquid medium containing dif- ferent concentrations and combinations of IBA, IAA, and NAA for 4 days, followed by transfer to growth regulators free half strength MS medium supplemented 0.25 mg l-1 activated charcoal. Elongated shoot treated with 15 lM IBA, 5.7 lM IAA, and 11 lM NAA resulted in highest percent rooting. The rooted plants could be established in soil with more than 90% survival rate. The method developed may be useful in improvement of J. curcas through genetic modification. © Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków 2010.

Shoot regeneration from cotyledonary leaf explants of jatropha curcas: A biodiesel plant

KAUST Repository

Kumar, Nitish Chandramohana; Vijay Anand, K. G.; Reddy, Muppala P.

2010-01-01

A simple, high frequency, and reproducible method for plant regeneration through direct organogenesis from cotyledonary leaf explants of Jatropha curcas was developed using Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ) or 6-benzyl aminopurine (BAP). Medium containing TDZ has greater influence on regeneration as compared to BAP. The induced shoot buds were transferred to MS medium containing 10 lM kinetin (Kn), 4.5 lM BAP, and 5.5 lM a-naphthaleneacetic acid (NAA) for shoot proliferation. The proliferated shoots could be elongated on MS medium supplemented with different concentrations and combinations of BAP, indole-3-acetic acid (IAA), NAA, and indole-3-butyric acid (IBA). MS medium with 2.25 lM BAP and 8.5 lM IAA was found to be the best combination for shoot elongation. However, significant differences in plant regeneration and shoot elongation were observed among the genotypes studied. Rooting was achieved when the basal cut end of elongated shoots were dipped in half strength MS liquid medium containing dif- ferent concentrations and combinations of IBA, IAA, and NAA for 4 days, followed by transfer to growth regulators free half strength MS medium supplemented 0.25 mg l-1 activated charcoal. Elongated shoot treated with 15 lM IBA, 5.7 lM IAA, and 11 lM NAA resulted in highest percent rooting. The rooted plants could be established in soil with more than 90% survival rate. The method developed may be useful in improvement of J. curcas through genetic modification. © Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków 2010.

Localization of cells containing sedimented amyloplasts in the shoots of normal and lazy rice seedlings.

Science.gov (United States)

Abe, K; Takahashi, H; Suge, H

1994-12-01

We have examined the localization of the cells containing sedimented amyloplasts (putative statocytes) and its relation to the graviresponding sites in the shoots of normal and lazy rice seedlings. All graviresponsive organs of the shoots of normal rice seedlings, the mesocotyl, the coleoptile and the leaf-sheath base, were found to possess the statocytes. This is the first indication that mesocotyl senses gravity by its own cells in inducing gravitropic bending in rice seedlings. In lazy-Kamenoo, although the shoots lost their gravitropic response with the advance of age, sedimentation of amyloplasts itself might not be attributable to the agravitropic growth of the shoots, because, including those of the leaf-sheath bases that had lost their response to gravity, sedimented amyloplasts appeared to be identical to those of normal Kamenoo and of younger seedlings of lazy-Kamenoo whose gravitropism is still apparent.

Shooting mechanisms in nature

NARCIS (Netherlands)

Sakes, Aimée; Wiel, van der Marleen; Henselmans, Paul W.J.; Leeuwen, van Johan L.; Dodou, Dimitra; Breedveld, Paul

2016-01-01

Background In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these

Alfalfa (Medicago sativa L.) shoot saponins: identification and bio-activity by the assessment of aphid feeding.

Science.gov (United States)

Mazahery-Laghab, H; Yazdi-Samadi, B; Bagheri, M; Bagheri, A R

2011-01-01

Biochemical components in alfalfa (Medicago sativa L.), such as saponins, can act as protecting factors against bio-stresses. Saponins are also antifeedants and show oral toxicity towards higher and lower animals. Changes in saponins, such as variation in the carbon skeleton, or hydrolysis of saponin glycosides and other conjugates, may change their biological effects. The aims of this research were to study saponin variation in different growth stages of alfalfa and to investigate the biological role of saponins in the spotted alfalfa aphid, Therioaphis maculata. Saponins from alfalfa shoots in different growth stages were extracted, chemically purified and analysed by TLC. Specific saponins such as soyasaponin1 from root and shoot and two bisdesmosides of medicagenic acid, one from shoot and another from root tissues, were identified using reference compounds allowing changes in saponin composition during plant development in different shoot tissues of alfalfa to be assessed. The response of the alfalfa aphid to feeding on alfalfa in different growth stages was studied. No significant difference in the survival of aphids, from neonate to adult, was observed, but due to the antibiotic effects of saponins, two differences were found in the onset of nymph production and cumulative nymph production. The results show that the saponin composition in alfalfa changes with plant development and this, in turn, can often negatively affect the development of specific insect pests such as the spotted alfalfa aphid, suggesting a possible biological role of alfalfa saponins.

The Nutritional Facts of Bamboo Shoots and Their Usage as Important Traditional Foods of Northeast India

Science.gov (United States)

Nongdam, P.; Tikendra, Leimapokpam

2014-01-01

Bamboo shoots are considered as one of the useful health foods because of their rich contents of proteins, carbohydrates, vitamins, fibres, and minerals and very low fat. Though bamboo shoots provide lots of health benefits, their consumption is confined mostly to Southeast Asian and East Asian countries. The acceptability of bamboo shoots as popular vegetable crop is very less due to their high pungent smell and bitter acidic taste. The use of bamboo as food in India is mainly restricted to Northeastern part of the country where they form an indispensable part of several traditional speciality dishes. The different ethnic communities take fresh or fermented bamboo shoot as one of most preferred traditional food items. Some of the important bamboo based traditional foods are ushoi, soibum, rep, mesu, eup, ekhung, hirring, and so forth. Bamboo shoots should be properly processed before they are consumed as freshly harvested shoots have high content of toxic cyanogenic glycosides which may pose serious health problems. The prospect of bamboo shoot industry in Northeast India is bright due to its rich genetic resources of bamboos. However, habitat destruction and extensive use of bamboos for food, handicraft, and construction purposes have resulted in severe depletion of natural bamboo resources. This review stresses upon the high nutritive values and health benefits of bamboo shoots and their usage as important traditional foods in Northeast India. The bamboo market potential of the region and use of in vitro plant micropropagation methods as effective means of bamboo conservation are also emphasized in this paper. PMID:27433496

Mass shooting and mass media : does media coverage of mass shootings inspire copycat crimes?

OpenAIRE

Mesoudi, A.

2013-01-01

In December 2012, twenty elementary school children and six adult staff members were shot and killed by a single individual at a school in Connecticut. Although this horrific event was met with widespread shock, Americans are sadly all too familiar with such mass shootings. From Columbine in 1999, to Virginia Tech in 2007, to the Colorado cinema shootings earlier in 2012, mass shootings seem to occur with alarming regularity. And although they appear to afflict the United States more than mos...

Gibberellin Promotes Shoot Branching in the Perennial Woody Plant Jatropha curcas.

Science.gov (United States)

Ni, Jun; Gao, Congcong; Chen, Mao-Sheng; Pan, Bang-Zhen; Ye, Kaiqin; Xu, Zeng-Fu

2015-08-01

Strigolactone (SL), auxin and cytokinin (CK) interact to regulate shoot branching. CK has long been considered to be the only key phytohormone to promote lateral bud outgrowth. Here we report that gibberellin also acts as a positive regulator in the control of shoot branching in the woody plant Jatropha curcas. We show that gibberellin and CK synergistically promote lateral bud outgrowth, and that both hormones influence the expression of putative branching regulators, J. curcas BRANCHED1 and BRANCHED2, which are key transcription factors maintaining bud dormancy. Moreover, treatment with paclobutrazol, an inhibitor of de novo gibberellin biosynthesis, significantly reduced the promotion of bud outgrowth by CK, suggesting that gibberellin is required for CK-mediated axillary bud outgrowth. In addition, SL, a plant hormone involved in the repression of shoot branching, acted antagonistically to both gibberellin and CK in the control of lateral bud outgrowth. Consistent with this, the expression of JcMAX2, a J. curcas homolog of Arabidopsis MORE AXILLARY GROWTH 2 encoding an F-box protein in the SL signaling pathway, was repressed by gibberellin and CK treatment. We also provide physiological evidence that gibberellin also induces shoot branching in many other trees, such as papaya, indicating that a more complicated regulatory network occurs in the control of shoot branching in some perennial woody plants. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.

[Effects of combined pollution of lead and benzo[a] pyrene on seed growth of wheat in soils].

Science.gov (United States)

Wang, Hong-Qi; Wang, Shuai; Ning, Shao-Wei; Sun, Yan-Ling; Hou, Ze-Qing

2011-03-01

Seed germination, root elongation, shoot elongation and ratio of shoot to root of wheat in soils polluted by lead (Pb) and benzo (a)pyrene (B[a] P) with medium-low concentrations were studied to reveal the ecological effects of combined pollution and screen the indicative markers. Results indicated that seed germination was not sensitive to single or combined pollution of Pb or B[a] P. Root elongation was inhibited by single pollution of Pb or B[a]P to different extents. Extensive interactions between Pb and B[a]P occurred to root elongation of wheat, including synergistic-stimulatory effect and antagonistic-inhibitory effect. The joint action was mainly antagonistic. Single pollution of B [a] P had an inhibitory effect on shoot elongation. Under combined pollution conditions, the shoot elongation of wheat correlated well with Pb contents (p pollutants had little effect on shoot elongation of wheat. The joint action on shoot elongation was consistently antagonistic. The response pattern of the ratio of shoot to root was similar to the response pattern of shoot elongation. However, the former had better correlation than the latter, indicating it as a more suitable indicative marker for Pb pollution. If lead acetate was employed instead of lead nitrate, longer root elongation, shorter shoot elongation and no effect on ratio of shoot to root were found. Therefore, the forms of Pb salt had significant influence on seed growth of wheat in soils.

The function of the RNA-binding protein TEL1 in moss reveals ancient regulatory mechanisms of shoot development.

Science.gov (United States)

Vivancos, Julien; Spinner, Lara; Mazubert, Christelle; Charlot, Florence; Paquet, Nicolas; Thareau, Vincent; Dron, Michel; Nogué, Fabien; Charon, Céline

2012-03-01

The shoot represents the basic body plan in land plants. It consists of a repeated structure composed of stems and leaves. Whereas vascular plants generate a shoot in their diploid phase, non-vascular plants such as mosses form a shoot (called the gametophore) in their haploid generation. The evolution of regulatory mechanisms or genetic networks used in the development of these two kinds of shoots is unclear. TERMINAL EAR1-like genes have been involved in diploid shoot development in vascular plants. Here, we show that disruption of PpTEL1 from the moss Physcomitrella patens, causes reduced protonema growth and gametophore initiation, as well as defects in gametophore development. Leafy shoots formed on ΔTEL1 mutants exhibit shorter stems with more leaves per shoot, suggesting an accelerated leaf initiation (shortened plastochron), a phenotype shared with the Poaceae vascular plants TE1 and PLA2/LHD2 mutants. Moreover, the positive correlation between plastochron length and leaf size observed in ΔTEL1 mutants suggests a conserved compensatory mechanism correlating leaf growth and leaf initiation rate that would minimize overall changes in plant biomass. The RNA-binding protein encoded by PpTEL1 contains two N-terminus RNA-recognition motifs, and a third C-terminus non-canonical RRM, specific to TEL proteins. Removal of the PpTEL1 C-terminus (including this third RRM) or only 16-18 amino acids within it seriously impairs PpTEL1 function, suggesting a critical role for this third RRM. These results show a conserved function of the RNA-binding PpTEL1 protein in the regulation of shoot development, from early ancestors to vascular plants, that depends on the third TEL-specific RRM.

Combined impact of water column oxygen and temperature on internal oxygen status and growth of Zostera marina seedlings and adult shoots

DEFF Research Database (Denmark)

Raun, Ane-Marie Løvendahl; Borum, Jens

2013-01-01

Eelgrass (Zostera marina L.) occasionally experiences severe die-offs during warm summer periods with variable water column oxygen partial pressures (pO). Eelgrass is known to be very intolerant to tissue anoxia with reduced growth and increasing mortality after ≤12h anoxia in the dark...... at temperatures of ≥25°C. In the present study we experimentally examine the impact of combined water column oxygen and temperature on oxygen dynamics in leaf meristems of seedlings and adult shoots to better understand how stressful environmental conditions affect eelgrass oxygen dynamics and subsequent growth...... and mortality. There was a strong interaction between water column oxygen and temperature on meristem pO implying that eelgrass is rather resistant to unfavorable oxygen conditions in winter but becomes increasingly vulnerable in summer, especially at high temperatures. At 25°C meristems became anoxic...

Roles of abscisic acid and auxin in shoot-supplied ammonium inhibition of root system development.

Science.gov (United States)

Li, Baohai; Li, Qing; Kronzucker, Herbert J; Shi, Weiming

2011-10-01

A plastic root system is a prerequisite for successful plant acclimation to variable environments. The normally functioning root system is the result of a complex interaction of root-borne signals and shoot-derived regulators. We recently demonstrated that AUX1, a well-studied component of auxin transport, mediates shoot-supplied ammonium (SSA) inhibition of lateral root (LR) formation in Arabidopsis. By contrast, the response did not involve ABA pathways, via which several other abiotic stresses affect LR formation. We proposed that SSA regulates LR emergence by interrupting AUX1-mediated auxin transport from shoot to root. Here, by analyzing both ABA- and auxin-related mutants, we show that AUX1 is also required for SSA-mediated suppression of primary root growth. Ammonium content in shoots was furthermore shown to increase linearly with shoot-, but not root-supplied, ammonium, suggesting it may represent the internal trigger for SSA inhibition of root development. Taken together, our data identify AUX1-mediated auxin transport as a key transmission step in the sensing of excessive ammonium exposure and its inhibitory effect on root development. 

Improved recovery of cryotherapy-treated shoot tips following thermotherapy of in vitro-grown stock shoots of raspberry (Rubus idaeus L.).

Science.gov (United States)

Wang, Qiaochun; Valkonen, Jari P T

2009-01-01

Raspberry bushy dwarf virus (RBDV) can be efficiently eradicated from raspberry plants (Rubus idaeus) by a procedure combining thermotherapy and cryotherapy. However, the bottleneck of this procedure is that, following thermotherapy, cryopreserved shoot tips become chlorotic during regrowth and eventually die after several subcultures. In addition, survival of heat-treated stock shoots and recovery of cryopreserved shoot tips following thermotherapy are low. The present study focused towards improving regrowth of cryopreserved raspberry shoot tips following thermotherapy. Results showed that preconditioning stock shoots with salicylic acid (SA; 0.01-0.1 mM) markedly increased survival of stock shoots after 4 weeks of thermotherapy. Regrowth of cryopreserved shoot tips following thermotherapy was also significantly enhanced when SA (0.05-0.1 mM) was used for preconditioning stock shoots. Addition of either Fe-ethylenediaminetetracetic acid (Fe-EDTA, 50 mg per L) or Fe-ethylenediaminedi(o)hydroxyphenylacetic acid (Fe-EDDHA, 50 mg per L) to post-culture medium strongly promoted regrowth and totally prevented chlorosis of shoots regenerated from cryopreserved shoot tips following thermotherapy. Using the parameters optimized in the present study, about 80 percent survival of heat-treated stock shoots and about 33 percent regrowth of cryopreserved shoot tips following thermotherapy were obtained. Morphology of plants regenerated from cryopreserved shoot tips following thermotherapy was identical to that of control plants, based on observations of leaf shape and size, internode length and plant height. Optimization of the thermotherapy procedure followed by cryotherapy will facilitate the wider application of this technique to eliminate viruses which can invade meristems.

Lengthwise shoot symmetry and its features in plants of Lamiaceae family of Ukrainian flora

Directory of Open Access Journals (Sweden)

Yosyp Berko

2014-04-01

Full Text Available The features of lengthwise symmetry of monocarpic shoots (on example of changing of the length of internodes in its elementar metamers in more than 60 species of half-shrub and grass plants from the family Lamiaceae were studied. The statistically representative plots of changes of this parameter for the most species appeared to be one-vertex, but very different by shape and specific. Two- and multi-vertex plots characterize limited number of species and appear as a result of quantized growth of shoots.

Effect of gamma irradiation on morphology of leaf and shoot apex of ginger, turmeric and mango-ginger

International Nuclear Information System (INIS)

Raju, E.C.; Patel, J.D.; Shah, J.J.

1980-01-01

Effect of 2, 5, 10, 20 and 30 kR gamma irradiation on morphology and growth of ginger (Zingiber officinale Rosc.), Turmeric (Curcuma domestica Valet) and mango-ginger (Curcuma amada Roxb), and shoot apical organisation in ginger was studied. Higher doses (20 and 30 kR) of radiation proved to be lethal. Morphological aberrations in foliage leaves are reported. Irradiated shoot apices appear histologically inert. (auth.)

Effect of gamma irradiation on morphology of leaf and shoot apex of ginger, turmeric and mango-ginger

Energy Technology Data Exchange (ETDEWEB)

Raju, E C; Patel, J D; Shah, J J [Sardar Patel Univ., Vallabh Vidyanagar (India). Dept. of Biosciences

1980-06-01

Effect of 2, 5, 10, 20 and 30 kR gamma irradiation on morphology and growth of ginger (Zingiber officinale Rosc.), Turmeric (Curcuma domestica Valet) and mango-ginger (Curcuma amada Roxb), and shoot apical organisation in ginger was studied. Higher doses (20 and 30 kR) of radiation proved to be lethal. Morphological aberrations in foliage leaves are reported. Irradiated shoot apices appear histologically inert.

Cytokinin induced shoot regeneration and flowering of Scoparia dulcis L. (Scrophulariaceae)-an ethnomedicinal herb.

Science.gov (United States)

Premkumar, G; Sankaranarayanan, R; Jeeva, S; Rajarathinam, K

2011-06-01

To develop an improved protocol for micropropagation of ethnomedicinally important Scoparia dulcis (S. dulcis) L. Explants were inoculated on MS basal medium supplemented with kinetin and 6-benzylaminopurine for shoot bud induction. To enhance the shoot induction, various auxins like 3-indoleacetic acid or 3-indolebutyric acid or α-naphthylacetic acid were tested along with 2.32 M KI and 4.44 µM BAP. The regenerated shoots were rooted in half strength MS medium supplemented with various concentrations of IAA, IBA or NAA. After roots were developed, the plantlets were transplanted to pots filled with vermiculate and sand and kept in growth chamber with 70%-80% humidity under 16 h photoperiod. After acclimatization, the plantlets were transferred to the garden and survival percentage was calculated. Data were statistically analyzed and means were compared using Duncan's multiple range test (Pdulcis. Shoot induction on young leaf explants was most successful in MS medium supplemented with combination of two cytokinins (2.32 µM KI and 4.44 µM BAP) 2.85 µM IAA, 10% CM and 1 483.79 µM adenine sulfate. A single young leaf explant was capable of producing 59 shoots after 13 days of culture. Flower was induced in medium supplemented with combination of KI and BAP. Cytokinins are the key factor to induce the direct shoot regeneration and flowering of S. dulcis.

Genotypic diversity of root and shoot characteristics of

Directory of Open Access Journals (Sweden)

ali ganjali

2009-06-01

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

Artificial neural network-based model for the prediction of optimal growth and culture conditions for maximum biomass accumulation in multiple shoot cultures of Centella asiatica.

Science.gov (United States)

Prasad, Archana; Prakash, Om; Mehrotra, Shakti; Khan, Feroz; Mathur, Ajay Kumar; Mathur, Archana

2017-01-01

An artificial neural network (ANN)-based modelling approach is used to determine the synergistic effect of five major components of growth medium (Mg, Cu, Zn, nitrate and sucrose) on improved in vitro biomass yield in multiple shoot cultures of Centella asiatica. The back propagation neural network (BPNN) was employed to predict optimal biomass accumulation in terms of growth index over a defined culture duration of 35 days. The four variable concentrations of five media components, i.e. MgSO 4 (0, 0.75, 1.5, 3.0 mM), ZnSO 4 (0, 15, 30, 60 μM), CuSO 4 (0, 0.05, 0.1, 0.2 μM), NO 3 (20, 30, 40, 60 mM) and sucrose (1, 3, 5, 7 %, w/v) were taken as inputs for the ANN model. The designed model was evaluated by performing three different sets of validation experiments that indicated a greater similarity between the target and predicted dataset. The results of the modelling experiment suggested that 1.5 mM Mg, 30 μM Zn, 0.1 μM Cu, 40 mM NO 3 and 6 % (w/v) sucrose were the respective optimal concentrations of the tested medium components for achieving maximum growth index of 1654.46 with high centelloside yield (62.37 mg DW/culture) in the cultured multiple shoots. This study can facilitate the generation of higher biomass of uniform, clean, good quality C. asiatica herb that can efficiently be utilized by pharmaceutical industries.

The Binomial Distribution in Shooting

Science.gov (United States)

Chalikias, Miltiadis S.

2009-01-01

The binomial distribution is used to predict the winner of the 49th International Shooting Sport Federation World Championship in double trap shooting held in 2006 in Zagreb, Croatia. The outcome of the competition was definitely unexpected.

CEP genes regulate root and shoot development in response to environmental cues and are specific to seed plants.

Science.gov (United States)

Delay, Christina; Imin, Nijat; Djordjevic, Michael A

2013-12-01

The manifestation of repetitive developmental programmes during plant growth can be adjusted in response to various environmental cues. During root development, this means being able to precisely control root growth and lateral root development. Small signalling peptides have been found to play roles in many aspects of root development. One member of the CEP (C-TERMINALLY ENCODED PEPTIDE) gene family has been shown to arrest root growth. Here we report that CEP genes are widespread among seed plants but are not present in land plants that lack true branching roots or root vasculature. We have identified 10 additional CEP genes in Arabidopsis. Expression analysis revealed that CEP genes are regulated by environmental cues such as nitrogen limitation, increased salt levels, increased osmotic strength, and increased CO2 levels in both roots and shoots. Analysis of synthetic CEP variants showed that both peptide sequence and modifications of key amino acids affect CEP biological activity. Analysis of several CEP over-expression lines revealed distinct roles for CEP genes in root and shoot development. A cep3 knockout mutant showed increased root and shoot growth under a range of abiotic stress, nutrient, and light conditions. We demonstrate that CEPs are negative regulators of root development, slowing primary root growth and reducing lateral root formation. We propose that CEPs are negative regulators that mediate environmental influences on plant development.

Date of shoot collection, genotype, and original shoot position affect early rooting of dormant hardwood cuttings of Populus

Science.gov (United States)

R. S., Jr. Zalesny; A.H. Wiese

2006-01-01

Identifying superior combinations among date of dormant- season shoot collection, genotype, and original shoot position can increase the rooting potential of Populus cuttings. Thus, the objectives of our study were to: 1) evaluate variation among clones in early rooting from hardwood cuttings processed every three weeks from shoots collected...

A phenological timetable of oak growth under experimental drought and air warming.

Directory of Open Access Journals (Sweden)

Thomas M Kuster

Full Text Available Climate change is expected to increase temperature and decrease summer precipitation in Central Europe. Little is known about how warming and drought will affect phenological patterns of oaks, which are considered to possess excellent adaptability to these climatic changes. Here, we investigated bud burst and intra-annual shoot growth of Quercus robur, Q. petraea and Q. pubescens grown on two different forest soils and exposed to air warming and drought. Phenological development was assessed over the course of three growing seasons. Warming advanced bud burst by 1-3 days °C⁻¹ and led to an earlier start of intra-annual shoot growth. Despite this phenological shift, total time span of annual growth and shoot biomass were not affected. Drought changed the frequency and intensity of intra-annual shoot growth and advanced bud burst in the subsequent spring of a severe summer drought by 1-2 days. After re-wetting, shoot growth recovered within a few days, demonstrating the superior drought tolerance of this tree genus. Our findings show that phenological patterns of oaks are modified by warming and drought but also suggest that ontogenetic factors and/or limitations of water and nutrients counteract warming effects on the biomass and the entire span of annual shoot growth.

Zinc oxide nanoparticle exposure triggers different gene expression patterns in maize shoots and roots

International Nuclear Information System (INIS)

Xun, Hongwei; Ma, Xintong; Chen, Jing; Yang, Zhongzhou; Liu, Bao; Gao, Xiang; Li, Guo; Yu, Jiamiao; Wang, Li; Pang, Jinsong

2017-01-01

The potential impacts of environmentally accumulated zinc oxide nanoparticles (nZnOs) on plant growth have not been well studied. A transcriptome profile analysis of maize exposed to nZnOs showed that the genes in the shoots and roots responded differently. Although the number of differentially expressed genes (DEGs) in the roots was greater than that in the shoots, the number of up- or down-regulated genes in both the shoots and roots was similar. The enrichment of gene ontology (GO) terms was also significantly different in the shoots and roots. The “nitrogen compound metabolism” and “cellular component” terms were specifically and highly up-regulated in the nZnO-exposed roots, whereas the categories “cellular metabolic process”, “primary metabolic process” and “secondary metabolic process” were down-regulated in the exposed roots only. Our results revealed the DEG response patterns in maize shoots and roots after nZnO exposure. - Highlights: • The gene expression patterns of maize exposed to ZnO nanoparticles (nZnO) varied in the shoots and roots. • A majority of the differentially expressed genes induced by nZnO exposure were exclusive to either the shoots or roots. • A similar number of up- and down-regulated genes was observed in the exposed shoots. • More up-regulated than down-regulated genes were found in the exposed roots. • A greater number of GO processes were observed in the nZnO exposed maize roots than in the exposed shoots. • GO terms in the “nitrogen compound metabolic process” category were exclusively and highly expressed in the exposed roots. • GO terms in the “nutrient reservoir” category were exclusively and highly expressed in the exposed roots. • Term “small molecule metabolic process” was also exclusively up-regulated in the exposed roots. • Processes in “cellular metabolic”, “primary metabolic” and “secondary metabolic” were down-regulated in the exposed roots.

Training visual control in wheelchair basketball shooting

NARCIS (Netherlands)

Oudejans, R.R.D.; Heubers, S.; Ruitenbeek, J-R.J.A.C.; Janssen, T.W.J.

2012-01-01

We examined the effects of visual control training on expert wheelchair basketball shooting, a skill more difficult than in regular basketball, as players shoot from a seated position to the same rim height. The training consisted of shooting with a visual constraint that forced participants to use

Plant regeneration from protoplasts ofVicia narbonensis via somatic embryogenesis and shoot organogenesis.

Science.gov (United States)

Tegeder, M; Kohn, H; Nibbe, M; Schieder, O; Pickardt, T

1996-11-01

Protoplasts ofVicia narbonensis isolated from epicotyls and shoot tips of etiolated seedlings were embedded in 1.4% sodium-alginate at a final density of 2.5×10(5) protoplasts/ml and cultivated in Kao and Michayluk-medium containing 0.5 mg/I of each of 2,4- dichlorophenoxyacetic acid, naphthylacetic acid and 6 -benzylaminopurine. A division frequency of 36% and a plating efficiency of 0.40-0.5% were obtained. Six weeks after embedding, protoplast-derived calluses were transferred onto gelrite-solidified Murashige and Skoog-media containing various growth regulators. Regeneration of plants was achieved via two morphologically distinguishable pathways. A two step protocol (initially on medium with a high auxin concentration followed by a culture phase with lowered auxin amount) was used to regenerate somatic embryos, whereas cultivation on medium containing thidiazuron and naphthylacetic acid resulted in shoot morphogenesis. Mature plants were recovered from both somatic embryos as well as from thidiazuron-induced shoots.

Rampage shootings: an historical, empirical, and theoretical overview.

Science.gov (United States)

Rocque, Michael; Duwe, Grant

2018-02-01

Rampage shootings is a relatively new term to describe a phenomenon that has a long history. Rampage shootings are mass shootings (generally defined as involving four or more victims), taking place in a public location, with victims chosen randomly or for symbolic purposes. These shootings are isolated events, meaning they are not connected to another criminal act (such as robbery or terrorism). Research suggests that rampage shootings are not a new phenomenon, but have occurred throughout the US since the early 1900s. There is some evidence of an increase in recent years, but definitional differences across studies and data sources make interpreting trends somewhat tenuous. Theories regarding the perpetration of rampage shootings center on masculinity, mental illness, and contagion effects. Policies aimed at preventing rampage shootings remain somewhat controversial and not well-tested in the literature. Copyright © 2017 Elsevier Ltd. All rights reserved.

Modeling shoot-tip temperature in the greenhouse environment

International Nuclear Information System (INIS)

Faust, J.E.; Heins, R.D.

1998-01-01

An energy-balance model is described that predicts vinca (Catharanthus roseus L.) shoot-tip temperature using four environmental measurements: solar radiation and dry bulb, wet bulb, and glazing material temperature. The time and magnitude of the differences between shoot-tip and air temperature were determined in greenhouses maintained at air temperatures of 15, 20, 25, 30, or 35 °C. At night, shoot-tip temperature was always below air temperature. Shoot-tip temperature decreased from 0.5 to 5 °C below air temperature as greenhouse glass temperature decreased from 2 to 15 °C below air temperature. During the photoperiod under low vapor-pressure deficit (VPD) and low air temperature, shoot-tip temperature increased ≈4 °C as solar radiation increased from 0 to 600 W·m -2 . Under high VPD and high air temperature, shoot-tip temperature initially decreased 1 to 2 °C at sunrise, then increased later in the morning as solar radiation increased. The model predicted shoot-tip temperatures within ±1 °C of 81% of the observed 1-hour average shoot-tip temperatures. The model was used to simulate shoot-tip temperatures under different VPD, solar radiation, and air temperatures. Since the rate of leaf and flower development are influenced by the temperature of the meristematic tissues, a model of shoot-tip temperature will be a valuable tool to predict plant development in greenhouses and to control the greenhouse environment based on a plant temperature setpoint. (author)

Cell walls as a stage for intercellular communication regulating shoot meristem development

Directory of Open Access Journals (Sweden)

Toshiaki eTameshige

2015-05-01

Full Text Available Aboveground organs of plants are ultimately derived/generated from the shoot apical meristem (SAM, which is the proliferative tissue located at the apex of the stem. The SAM contains a population of stem cells that provide new cells for organ/tissue formation. The SAM is composed of distinct cell layers and zones with different properties. Primordia of lateral organs develop at the periphery of the SAM. The shoot apex is a dynamic and complex tissue, and as such intercellular communications among cells, layers and zones play significant roles in the coordination of cell proliferation, growth and differentiation to achieve elaborate morphogenesis. Recent findings have highlighted the importance of a number of singling molecules acting in the cell wall space for the intercellular communication, including classic phytohormones and secretory peptides. Moreover, accumulating evidences reveal that cell wall properties and their modifying enzymes modulate hormone actions. In this review, we overview how behaviors of singling molecules and changes of cell wall properties are integrated for the shoot meristem regulation.

Resposta à regeneração e crescimento de brotos in vitro de Kielmeyera coriacea quando influenciado por diferentes concentrações dos sais e de sacarose In vitro regeneration and growth response of Kielmeyera coriacea shoots when affected by salts and sucrose concentrations

Directory of Open Access Journals (Sweden)

José Eduardo Brasil Pereira Pinto

1996-04-01

Full Text Available Avaliaram-se diferentes concentrações de sacarose e sais do MS (MURASHIGE & SKOOG, J 962 na regeneração e crescimento de brotos de Kielmeyera coriacea in vitro. A redução e o aumento da quantidade de sacarose partindo de 30 e 45g/L, respectivamente, causou um decréscimo no número total de brotos. O uso integral ou da metade das concentrações dos sais do MS proporcionou maiores taxas de multiplicação. A maior porcentagem de brotos com mais de 1,0cm de comprimento pôde ser obtida empregando-se 30 g/l de sacarose associado a concentração 1/1 do MS. A porcentagem média de brotos decresceu linearmente com a diluição salina.Trials were carried out to test sucrose and salt concentrations added to growth medium on regeneration and growth response of Kielmeyera coriacea shoots. The reduction and increase of sucrose of 30 and 45g/l, rerspectively, caused a decrease in total number of shoots. A higher shoots percentage of with more than 1.0cm, occurred on media with 30g/L of sucrose. The use of total force (1/1 and half strength (1/2 of MS salt proportioned a higher shoot ratio and growth.

Shoot regeneration of limau purut (citrus hystrix) using shoot tip: assessment of calcium gluconate and silver nitrate in overcoming premature leaf senescence

International Nuclear Information System (INIS)

Eng, W.H.; Aziz, M.A.; Sinniah, U.R.

2014-01-01

This study was carried out to establish an optimum In vitro shoot multiplication system using shoot tip explants derived from 7 week-old seedlings of Citrus hystrix. In the first experiment, shoot tips were cultured on Murashige and Skoog (MS) medium supplemented with 0-13.33 mu M 6-benzylaminopurine (BAP) for 8 weeks. Shoot tips cultured on 2.22 mu M BAP produced the highest mean number of shoots (3.42 shoots) but the shoots had low number of leaves (1.14 leaves) due to the occurrence of premature leaf senescence and callus formation. Meanwhile, the medium devoid of BAP produced the lowest mean number of shoots (1.50 shoots) but highest mean number of leaves (5.41 leaves) indicating that BAP was likely responsible for the premature leaf senescence. In order to overcome the occurrence of premature leaf senescence on medium with BAP, a second experiment was carried out whereby shoot tips were cultured on medium containing 2.22 micro M BAP fortified with 2.00, 4.00 and 6.00 mM calcium gluconate (Ca-glu) and a control treatment with 2.22 mu M BAP. The shoot and leaf numbers were increased with the addition of 4.00 and 6.00 mM Ca-glu. The presence of Ca-glu reduced premature leaf senescence and callus formation to some extent. In the third experiment, the addition of silver nitrate (AgNO/sub 3/) at 10-80 micro M in media with 2.22 micro M BAP and 2.22 micro M BAP + 4 mM Ca-glu could totally overcome premature leaf senescence and callus formation. Media supplemented with 2.22 mirco M BAP + 4 mM Ca-glu + 20 micro M AgNOsub 3/ significantly induced among the highest mean number of shoots and highest mean number of leaves per shoot. (author)

Training Visual Control in Wheelchair Basketball Shooting

Science.gov (United States)

Oudejans, Raoul R. D.; Heubers, Sjoerd; Ruitenbeek, Jean-Rene J. A. C.; Janssen, Thomas W. J.

2012-01-01

We examined the effects of visual control training on expert wheelchair basketball shooting, a skill more difficult than in regular basketball, as players shoot from a seated position to the same rim height. The training consisted of shooting with a visual constraint that forced participants to use target information as late as possible.…

Plants know where it hurts: root and shoot jasmonic acid induction elicit differential responses in Brassica oleracea.

Directory of Open Access Journals (Sweden)

Tom O G Tytgat

Full Text Available Plants respond to herbivore attack by rapidly inducing defenses that are mainly regulated by jasmonic acid (JA. Due to the systemic nature of induced defenses, attack by root herbivores can also result in a shoot response and vice versa, causing interactions between above- and belowground herbivores. However, little is known about the molecular mechanisms underlying these interactions. We investigated whether plants respond differently when roots or shoots are induced. We mimicked herbivore attack by applying JA to the roots or shoots of Brassica oleracea and analyzed molecular and chemical responses in both organs. In shoots, an immediate and massive change in primary and secondary metabolism was observed. In roots, the JA-induced response was less extensive and qualitatively different from that in the shoots. Strikingly, in both roots and shoots we also observed differential responses in primary metabolism, development as well as defense specific traits depending on whether the JA induction had been below- or aboveground. We conclude that the JA response is not only tissue-specific but also dependent on the organ that was induced. Already very early in the JA signaling pathway the differential response was observed. This indicates that both organs have a different JA signaling cascade, and that the signal eliciting systemic responses contains information about the site of induction, thus providing plants with a mechanism to tailor their responses specifically to the organ that is damaged.

Cotton growth potassium deficiency stress is influenced by photosynthetic apparatus and root system

International Nuclear Information System (INIS)

Hussain, Z.U.; Arshad, M.

2010-01-01

Due to rapid depletion of soil potassium (K) and increasing cost of K fertilizers in Pakistan, the K-use efficient crop genotypes become very important for agricultural sustain ability. However, limited research has been done on this important issue particularly in cotton, an important fibre crop. We studied the growth and biomass production of three cotton genotypes (CIM-506, NIAB- 78 and NIBGE-2) different in K-use efficiency in a K-deficient solution culture. Genotypes differed significantly for biomass production, absolute growth rates (shoot, root, leaf, total), leaf area, mean leaf area and relative growth rate of leaf under K deficiency stress, besides specific leaf area. The relative growth rate (shoot, root, total) did not differ significantly, except for leaf. For all these characters, NIBGE-2 was the best performer followed by NIAB-78 and CIM-506. Shoot dry weight was significantly related with (in decreasing order of significance): mean leaf area, leaf dry weight, leaf area, root dry weight, absolute growth rate of shoot, absolute growth rate of root, absolute growth rate total, absolute growth rate root, relative growth rate leaf, relative growth rate total and relative growth rate shoot. Hence, the enhanced biomass accumulation of cotton genotypes under K deficiency stress is related to their efficient photosynthetic apparatus and root system, appeared to be the most important morphological markers while breeding for K-use efficient cotton genotypes.(author)

In vitro conservation of Piper aduncum and Piper hispidinervum under slow-growth conditions

Directory of Open Access Journals (Sweden)

Tatiane Loureiro da Silva

2011-04-01

Full Text Available The objective of this work was to evaluate in vitro storage of Piper aduncum and P. hispidinervum under slow-growth conditions. Shoots were stored at low temperatures (10, 20 and 25°C, and the culture medium was supplemented with osmotic agents (sucrose and mannitol - at 1, 2 and 3% and abiscisic acid - ABA (0, 0.5, 1.0, 2.0 and 3.0 mg L-1. After six-months of storage, shoots were evaluated for survival and regrowth. Low temperature at 20ºC was effective for the in vitro conservation of P. aduncum and P. hispidinervum shoots. In vitro cultures maintained at 20ºC on MS medium showed 100% survival with slow-growth shoots. The presence of mannitol or ABA, in the culture medium, negatively affected shoot growth, which is evidenced by the low rate of recovered shoots.

A School Shooting Plot Foiled

Science.gov (United States)

Swezey, James A.; Thorp, Kimberly A.

2010-01-01

Dinkes, Cataldi, and Lin-Kelly (2007) claims that 78% of public schools reported one or more violent incidents during the 2005/2006 school year. School shootings are a rare but real threat on school campuses. Shootings at private schools are even less frequent with only a few recorded examples in the United States. This case study examines how a…

Root and aerial growth in early-maturing peach trees under two crop load treatments

Energy Technology Data Exchange (ETDEWEB)

Abrisqueta, I.; Conejero, W.; López-Martínez, L.; Vera, J.; Ruiz Sánchez, M.C.

2017-07-01

The objectives of the paper were to study the pattern of root growth (measured by minirhizotrons) in relation to trunk, fruit and shoot growth and the effects of crop load on tree growth and yield in peach trees. Two crop load (commercial and low) treatments were applied in a mature early-maturing peach tree orchard growing in Mediterranean conditions. Root growth dynamics were measured using minirhizotrons during one growing season. Shoot, trunk and fruit growth were also measured. At harvest, all fruits were weighed, counted and sized. Roots grew throughout the year but at lower rates during the active fruit growth phase. Root growth was asynchronous with shoot growth, while root and trunk growth rates were highest after harvest, when the canopy was big enough to allocate the photo-assimilates to organs that would ensure the following season’s yield. Shoot and fruit growth was greater in the low crop load treatment and was accompanied by a non-significant increase in root growth. High level of fruit thinning decreased the current yield but the fruits were more marketable because of their greater size.

Shoot growth, root growth and resource capture under limiting water and N supply for two cultivars of lettuce (Lactuca sativa L.)

NARCIS (Netherlands)

Kerbiriou, P.J.; Stomph, T.J.; Putten, van der P.E.L.; Lammerts Van Bueren, E.; Struik, P.C.

2013-01-01

Background and aims - To improve vegetable crops adapted to low input and variable resource availability, better understanding is needed of root system functioning, including nitrogen and water capture. Methods - This study quantified shoot and root development and patterns of water and nitrate

Mass Shootings, Mental Illness, and Gun Control.

Science.gov (United States)

Philpott-Jones, Sean

2018-03-01

In the wake of the Stoneman Douglas School shooting, Republican and Democratic leaders-like the American electorate they represent-remain sharply divided in their responses to gun violence. They are united in their condemnation of these mass shootings, but they disagree about whether stricter or looser gun control laws are the answer. Those on the right side of the political aisle suggest that the issue is one of mental illness rather than gun control. Conversely, those who are more liberal or progressive in their political learnings are quick to condemn attempts to reframe the issue of mass shootings as a mental health problem. Both sides are wrong. Mass shootings are indeed partially a mental health problem, albeit one poorly addressed by our current laws and policies. But the solution to mass shootings also needs to consider strategies that may reduce gun violence in general. © 2018 The Hastings Center.

SHOOT2.0: An indirect grid shooting package for optimal control problems, with switching handling and embedded continuation

OpenAIRE

Martinon , Pierre; Gergaud , Joseph

2010-01-01

The SHOOT2.0 package implements an indirect shooting method for optimal control problems. It is specifically designed to handle control discontinuities, with an automatic switching detection that requires no assumptions concerning the number of switchings. Special care is also devoted to the computation of the Jacobian matrix of the shooting function, using the variational system instead of classical finite differences. The package also features an embedded continuation method and an automati...

Effect of irradiance and spectral composition of radiation on in vitro shoot proliferation in Malus domestica

International Nuclear Information System (INIS)

Noè, N.; Eccher, T.; Bonini, L.

1997-01-01

Four clones of Malus domestica cv. Golden Delicious - namely Smoothee, Crielaard, Reinders and Golden B - were cultured in vitro from single-node microcuttings placed on solid medium under irradiance (PPFD) of 50 micromol m -2 s -1 . After 9 months an average shoot proliferation of 5.3 was achieved; Crielaard showed the highest rate (7.1), followed Golden B (5.4), Smoothee and Reinders (4.4). Proliferating shoots were then exposed to higher PPFD (80 micromol m -2 s -1 ) and different spectral composition of radiation using PMMA-B and PMMA-R/FR filters. High PPFD decreased the average proliferation rate to 4.5, in particular in Crielaard and Golden B, while it increased proliferation in Reinders. When a PMMA-R/FR filter was interposed, the mean proliferation rate slightly increased. PMMA-B filters decreased the overall proliferation rate to 3.0; only in Crielaard it was increased, but shoots were very small. Thus PPFD and spectral composition influenced in vitro shoot proliferation and growth and the responses were different among the clones. (author)

Cadmium uptake from solution by plants and its transport from roots to shoots

Energy Technology Data Exchange (ETDEWEB)

Jarvis, S.C.; Jones, L.H.P.; Hopper, M.J.

1976-02-01

The uptake of cadmium by the roots of plants, and its transport to shoots was examined using solution culture. Uptake by the roots of perennial ryegrass over a period of 4 hours from an aqueous solution containing 0.25 ppm cadmium as CdCl/sub 2/ was (i) enhanced by killing the roots and (ii) depressed when Ca/sup 2 +/, Mn/sup 2 +/ or Zn/sup 2 +/ were added to the solution. The distribution of cadmium between the roots and shoots of 23 species was examined at 4 days after a single, 3-day exposure to a nutrient solution containing 0.01 ppm added Cd. In all except 3 species, i.e. kale, lettuce and watercress, more than 50% of that taken up was retained in the shoot, and in fibrous roots of fodder beet, parsnip, carrot and radish it was greater than in the swollen storage roots. When perennial ryegrass was similarly exposed to solutions containing 0.01, 0.05, and 0.25 ppm added cadmium, uptake, as measured at 3 days after adding cadmium, increased with increasing rates of addition, but the proportion retained in the roots was constant (approximately 88%). There was no further transport from roots to shoots during the next 21 days, with the result that the concentration in the shoots decreased progressively with increasing growth. It is concluded that although the roots of several species can take up large quantities of cadmium from solution there are mechanisms which may restrict the movement of cadmium through plants, and thus to animals. 21 references, 7 tables.

School shootings: law enforcement and school district networking

OpenAIRE

Topadzhikyan, Tigran

2013-01-01

CHDS State/Local School shootings have happened in the past and will happen again. The history of school shootings prompts all stakeholders to look at ways to prevent them from happening, and if they do happen, to be resilient. Change is needed in the prevention of school shootings. The case studies of Virginia Tech, Sandy Hook, E. O. Green Junior High, and Beslan school shootings reveal that the lack of information sharing and lack of communication were flaws; and the incidents might have...

Promising role of plant hormones in translocation of lead in Sesbania drummondii shoots

International Nuclear Information System (INIS)

Israr, Mohd; Sahi, Shivendra V.

2008-01-01

Lead (Pb) accumulation in Sesbania drummondii shoots was enhanced by 654 and 415% in the presence of 100 μM IAA and 100 μM NAA, respectively, compared to control plants (Pb alone). However, when IAA or NAA was added along with EDTA, Pb accumulation further increased in shoots by 1349% and 1252%, respectively. Scanning electron microscopic observations revealed that Pb particles in both leaf and stem of Pb + EDTA + IAA and Pb + EDTA + NAA treated plants were concentrated in the region of vascular bundles. In root tissue, Pb particles were present between epidermis to stele region. Plant growth in both treatments (Pb + 100 μM IAA and Pb + 100 μM NAA) was comparable to control plants; however, it was significantly inhibited in the treatments containing Pb + EDTA and EDTA at concentrations of 10 μM of IAA or NAA. Moreover, the photosynthetic efficiency and strength of the treated plants were not affected in the presence of IAA or NAA and EDTA. - Plant hormones (IAA and NAA) enhance the accumulation of lead in shoots of Sesbania drummondii

Regeneration and growth rates of allofragments in four common stream plants

DEFF Research Database (Denmark)

Riis, Tenna; Madsen, Tom Vindbæk; Sennels, R. S. H.

2009-01-01

perfoliatus L. and Ranunculus baudotii x pseudofluitans. The objectives of this study were to determine (1) if shoots with an apical tip have higher regeneration (growth of new shoots and rhizomes from allofragments) and colonisation (root attachment in sediment) abilities and higher relative growth rates...

Plantlets from encapsulated shoot buds of Catalpa ovata G. Don

Directory of Open Access Journals (Sweden)

Halina Wysokińska

2014-01-01

Full Text Available Shoot buds isolated from in vitro shoot cultures of Catalpa ovata G. Don were encapsulated using 3% sodium alginate with sucrose (3% and 50 mM calcium chloride. The morphogenic response of encapsulated buds was affected by such factors, like composition of the media and the presence of growth regulators. The highest frequency of plantlet germination from encapsulated buds (70% within 4 weeks was obtained on Woody Plant medium (WP (Lloyd and McCown 1980 containing indole-3-butyric acid (IBA (1 mg/l. The process was substantially inhibited by cold-storage (4oC of encapsulated buds. In this case, the frequency response ranged from 3% to 22% dependent on storage period (28 or 42 days and the presence of the paraffin coat covering the alginate capsules. The plantlets developed from both unstored and stored encapsulated buds of C. ovata were transplanted to soil and grew in pots to phenotypically normal plants.

Effects of gibberellic acid on growth and photosynthetic pigments of ...

African Journals Online (AJOL)

The aim of this study was to improve growth performance by enhancing the photosynthetic pigments and enzyme carbonic anhydrase (CA) activity of Hibiscus sabdariffa L. (cv. Sabahia 17) under NaCl stress. Under non-saline condition, application of GA3 enhanced growth parameters (shoot length, shoot fresh weight (FW) ...

Improving growth and yield of cowpea by foliar application of ...

African Journals Online (AJOL)

Water stress impaired cowpea plant growth and decreased ion percentage and chlorophyll and carbohydrate concentration in the shoot as well as yield and its quality. Foliar-applied chitosan, in particular 250 mg/l, increased plant growth, yield and its quality as well as physiological constituents in plant shoot under stressed ...

Shooting Mechanisms in Nature: A Systematic Review.

Directory of Open Access Journals (Sweden)

Aimée Sakes

Full Text Available In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these mechanisms fulfill.We systematically searched the literature using Scopus and Web of Knowledge to retrieve articles about solid projectiles that either are produced in the body of the organism or belong to the body and undergo a ballistic phase. The shooting mechanisms were categorized based on the energy management prior to and during shooting.Shooting mechanisms were identified with projectile masses ranging from 1·10-9 mg in spores of the fungal phyla Ascomycota and Zygomycota to approximately 10,300 mg for the ballistic tongue of the toad Bufo alvarius. The energy for shooting is generated through osmosis in fungi, plants, and animals or muscle contraction in animals. Osmosis can be induced by water condensation on the system (in fungi, or water absorption in the system (reaching critical pressures up to 15.4 atmospheres; observed in fungi, plants, and animals, or water evaporation from the system (reaching up to -197 atmospheres; observed in plants and fungi. The generated energy is stored as elastic (potential energy in cell walls in fungi and plants and in elastic structures in animals, with two exceptions: (1 in the momentum catapult of Basidiomycota the energy is stored in a stalk (hilum by compression of the spore and droplets and (2 in Sphagnum energy is mainly stored in compressed air. Finally, the stored energy is transformed into kinetic energy of the projectile using a catapult mechanism delivering up to 4,137 J/kg in the osmotic shooting mechanism in cnidarians and 1,269 J/kg in the muscle-powered appendage strike of the mantis shrimp Odontodactylus scyllarus. The launch accelerations range from 6.6g in the frog Rana pipiens to 5,413,000g in

Effects of fungicides and bactericides on orchid seed germination and shoot tip cultures in vitro

OpenAIRE

Brown, DM; Groom, CL; Cvitanik, M; Brown, M; Cooper, JL; Arditti, J

1981-01-01

Amphotericin B, benomyl, gentamycin, nystatin, quintozene penicillin G, sodium omadine, and vancomycin singly and in several combinations have no deleterious effects on the germination of orchid seeds, but inhibit the growth in vitro of shoot tip explants. © 1981 Martinus Nijhoff/Dr W. Junk Publishers.

Arabidopsis brassinosteroid biosynthetic mutant dwarf7-1 exhibits slower rates of cell division and shoot induction

Directory of Open Access Journals (Sweden)

Schulz Burkhard

2010-12-01

Full Text Available Abstract Background Plant growth depends on both cell division and cell expansion. Plant hormones, including brassinosteroids (BRs, are central to the control of these two cellular processes. Despite clear evidence that BRs regulate cell elongation, their roles in cell division have remained elusive. Results Here, we report results emphasizing the importance of BRs in cell division. An Arabidopsis BR biosynthetic mutant, dwarf7-1, displayed various characteristics attributable to slower cell division rates. We found that the DWARF4 gene which encodes for an enzyme catalyzing a rate-determining step in the BR biosynthetic pathways, is highly expressed in the actively dividing callus, suggesting that BR biosynthesis is necessary for dividing cells. Furthermore, dwf7-1 showed noticeably slower rates of callus growth and shoot induction relative to wild-type control. Flow cytometric analyses of the nuclei derived from either calli or intact roots revealed that the cell division index, which was represented as the ratio of cells at the G2/M vs. G1 phases, was smaller in dwf7-1 plants. Finally, we found that the expression levels of the genes involved in cell division and shoot induction, such as PROLIFERATING CELL NUCLEAR ANTIGEN2 (PCNA2 and ENHANCER OF SHOOT REGENERATION2 (ESR2, were also lower in dwf7-1 as compared with wild type. Conclusions Taken together, results of callus induction, shoot regeneration, flow cytometry, and semi-quantitative RT-PCR analysis suggest that BRs play important roles in both cell division and cell differentiation in Arabidopsis.

Transcriptome Analysis of ABA/JA-Dual Responsive Genes in Rice Shoot and Root.

Science.gov (United States)

Kim, Jin-Ae; Bhatnagar, Nikita; Kwon, Soon Jae; Min, Myung Ki; Moon, Seok-Jun; Yoon, In Sun; Kwon, Taek-Ryoun; Kim, Sun Tae; Kim, Beom-Gi

2018-01-01

The phytohormone abscisic acid (ABA) enables plants to adapt to adverse environmental conditions through the modulation of metabolic pathways and of growth and developmental programs. We used comparative microarray analysis to identify genes exhibiting ABA-dependent expression and other hormone-dependent expression among them in Oryza sativa shoot and root. We identified 854 genes as significantly up- or down-regulated in root or shoot under ABA treatment condition. Most of these genes had similar expression profiles in root and shoot under ABA treatment condition, whereas 86 genes displayed opposite expression responses in root and shoot. To examine the crosstalk between ABA and other hormones, we compared the expression profiles of the ABA-dependently regulated genes under several different hormone treatment conditions. Interestingly, around half of the ABA-dependently expressed genes were also regulated by jasmonic acid based on microarray data analysis. We searched the promoter regions of these genes for cis-elements that could be responsible for their responsiveness to both hormones, and found that ABRE and MYC2 elements, among others, were common to the promoters of genes that were regulated by both ABA and JA. These results show that ABA and JA might have common gene expression regulation system and might explain why the JA could function for both abiotic and biotic stress tolerance.

Sound propagation from a semi-open shooting range

NARCIS (Netherlands)

Eerden, F.J.M. van der; Berg, F. van den

2011-01-01

Semi-open shooting ranges, in contrast to a fully open shooting range, are often used in the densely populated area of the Netherlands. The Ministry of Defense operates a number of these ranges. In these shooting ranges above the line of fire a number of screens are situated for safety precautions

Water Status Related Root-to-Shoot Communication Regulates the Chilling Tolerance of Shoot in Cucumber (Cucumis sativus L.) Plants.

Science.gov (United States)

Zhang, Zi-Shan; Liu, Mei-Jun; Gao, Hui-Yuan; Jin, Li-Qiao; Li, Yu-Ting; Li, Qing-Ming; Ai, Xi-Zhen

2015-10-16

Although root-to-shoot communication has been intensively investigated in plants under drought, few studies have examined root-to-shoot communication under chilling. Here we explored whether root-to-shoot communication contributes to the chilling-light tolerance of cucumber shoots and clarified the key signal involves in this communication. After leaf discs chilling-light treatment, the photoinhibitions of Photosystem I (PSI) and Photosystem II (PSII) were similar in leaf discs of two cucumber varieties (JY-3 and JC-4). When the whole plants, including roots, were chilled under light, the photosynthetic performances in JC-4 leaves decreased more seriously than that in JY-3 leaves. However, when the water status of leaves was maintained by warming roots or floating the attached leaves on water, the PSII activity and amount of PSI in the leaves of the two varieties were similar after chilling-light treatment. In addition, the differences of PSII activities and amount of PSI between the two varieties under whole plant chilling-light treatment were independent of ABA pretreatment. Above results indicate that (1) the better water status in leaves under chilling contributes to the higher chilling tolerance of JY-3; (2) the water status, rather than an ABA signal, dominates root-to-shoot communication under chilling and the chilling tolerance of cucumber shoot.

GENETIC RELATIONSHIP BETWEEN PLANT GROWTH, SHOOT ...

African Journals Online (AJOL)

AISA

2Department of Plant Sciences, North Dakota State University, Fargo, ND 58105, USA. ABSTRACT. Maize (Zea mays L.) ear vascular tissue transports nutrients that contribute to grain yield. To assess kernel heritabilities that govern ear development and plant growth, field studies were conducted to determine the combining ...

Does shoot water status limit leaf expansion of nitrogen-deprived barley?

Science.gov (United States)

Dodd, I C; Munns, Rana; Passioura, J B

2002-08-01

The role of shoot water status in mediating the decline in leaf elongation rate of nitrogen (N)-deprived barley plants was assessed. Plants were grown at two levels of N supply, with or without the application of pneumatic pressure to the roots. Applying enough pressure (balancing pressure) to keep xylem sap continuously bleeding from the cut surface of a leaf allowed the plants to remain at full turgor throughout the experiments. Plants from which N was withheld required a greater balancing pressure during both day and night. This difference in balancing pressure was greater at high (2.0 kPa) than low (1.2 kPa) atmospheric vapour pressure deficit (VPD). Pressurizing the roots did not prevent the decline in leaf elongation rate induced by withholding N at either high or low VPD. Thus low shoot water status did not limit leaf growth of N-deprived plants.

Development and validation of an extensive growth and growth boundary model for psychrotolerant Lactobacillus spp. in seafood and meat products

DEFF Research Database (Denmark)

Mejlholm, Ole; Dalgaard, Paw

2013-01-01

A new and extensive growth and growth boundary model for psychrotolerant Lactobacillus spp. was developed and validated for processed and unprocessed products of seafood and meat. The new model was developed by refitting and expanding an existing cardinal parameter model for growth and the growth...... of psychrotolerant Lactobacillus spp. was clearly demonstrated. The new model can be used to predict growth of psychrotolerant Lactobacillus spp. in seafood and meat products e.g. prediction of the time to a critical cell concentration of bacteria is considered useful for establishing the shelf life. In addition...... boundary of lactic acid bacteria (LAB) in processed seafood (O. Mejlholm and P. Dalgaard, J. Food Prot. 70. 2485–2497, 2007). Initially, to estimate values for the maximum specific growth rate at the reference temperature of 25°C (μref) and the theoretical minimum temperature that prevents growth...

The use of 32P to study root growth of soybean as affected by soil compaction

International Nuclear Information System (INIS)

Sisworo, Elsje L.; Sisworo, Widjang H.; Syaukat, Sri Harti; Wemay, Johannis; Haryanto

1996-01-01

Two greenhouse and two field experiments have been conducted to study the effect of soil compaction on root and plant growth of soybean, by using 32 P in the form of carrier free KH 2 32 PO 4 solution. In the greenhouse experiment it was clearly shown that by increasing soil compaction the growth of roots and shoots was increasingly inhibited. The growth of roots was expressed in √% arcsin converted from 32 P activity (counts per minute, cpm) in the shoots and 32 P activity in the shoots (cpm) without convertion. Plant growth was expressed in plant height, number of leaves, dry weight of pods and shoots. In the field experiment, it was shown distinctively that root growth in the 15 cm soil depth was inhibited whith the increase of soil compaction. Similar with the greenhouse experiments the of plants of roots was expressed in cpm 32 P of roots, shoots, and pods, while, the growth of plants was expressed in plant height, number of pods, and dry weight of pods, seeds, and stover. (author). 19 refs, 4 tabs, 6 figs

Characteristics of schools in which fatal shootings occur.

Science.gov (United States)

de Apodaca, Roberto Flores; Brighton, Lauren M; Perkins, Ashley N; Jackson, Kiana N; Steege, Jessica R

2012-04-01

School-based violence, and fatal school shootings in particular, have gained increased attention in the media and psychological literature. Most reports have focused on the characteristics of perpetrators, but there is a growing awareness that school-related factors may also influence the occurrence of fatal school shootings. The current study examined several key characteristics of all schools where random (38) and targeted (96) fatal shootings occurred in the United States between 1966 and 2009. These were compared with a group (138) of schools randomly selected to represent the population of all schools in the United States. The size of a school's enrollment, urban or suburban locale, public funding, and predominantly non-white enrollment were positively associated with fatal shootings. Universities and colleges were disproportionately associated with random shootings and high schools with targeted ones. It was proposed that characteristics of schools that allow feelings of anonymity or alienation among students may help create environmental conditions associated with fatal school shootings. Implications for future research and interventions are considered.

Effects of glucose irradiated by high doses of 60cobalt gamma rays, and of some products of glucose radiolysis on the growth of Jerusalem Artichoke tissue and potato shoots culture in vitro

International Nuclear Information System (INIS)

Manant, Pierre

1975-01-01

Glucose, irradiated in dry conditions by gamma rays from 5.10 5 to 10 7 rad, and incorporated into culture medium, inhibits growth and, simultaneously, increases rhizogenesis of Jerusalem Artichoke tissue in culture. Tuberisation of potato shoots grown in vitro is delayed and partially inhibited. Some substances which result from radiolysis of sugars give the same results, but only at higher concentrations [fr

The Level of Vision Necessary for Competitive Performance in Rifle Shooting: Setting the Standards for Paralympic Shooting with Vision Impairment.

Science.gov (United States)

Allen, Peter M; Latham, Keziah; Mann, David L; Ravensbergen, Rianne H J C; Myint, Joy

2016-01-01

The aim of this study was to investigate the level of vision impairment (VI) that would reduce performance in shooting; to guide development of entry criteria to visually impaired (VI) shooting. Nineteen international-level shooters without VI took part in the study. Participants shot an air rifle, while standing, toward a regulation target placed at the end of a 10 m shooting range. Cambridge simulation glasses were used to simulate six different levels of VI. Visual acuity (VA) and contrast sensitivity (CS) were assessed along with shooting performance in each of seven conditions of simulated impairment and compared to that with habitual vision. Shooting performance was evaluated by calculating each individual's average score in every level of simulated VI and normalizing this score by expressing it as a percentage of the baseline performance achieved with habitual vision. Receiver Operating Characteristic curves were constructed to evaluate the ability of different VA and CS cut-off criteria to appropriately classify these athletes as achieving 'expected' or 'below expected' shooting results based on their performance with different levels of VA and CS. Shooting performance remained relatively unaffected by mild decreases in VA and CS, but quickly deteriorated with more moderate losses. The ability of visual function measurements to classify shooting performance was good, with 78% of performances appropriately classified using a cut-off of 0.53 logMAR and 74% appropriately classified using a cut-off of 0.83 logCS. The current inclusion criteria for VI shooting (1.0 logMAR) is conservative, maximizing the chance of including only those with an impairment that does impact performance, but potentially excluding some who do have a genuine impairment in the sport. A lower level of impairment would include more athletes who do have a genuine impairment but would potentially include those who do not actually have an impairment that impacts performance in the sport. An

Hormonal regulation of wheat growth during hydroponic culture

Science.gov (United States)

Wetherell, Donald

1988-01-01

Hormonal control of root growth has been explored as one means to alleviate the crowding of plant root systems experienced in prototype hydroponic biomass production chambers being developed by the CELSS Breadboard Project. Four plant hormones, or their chemical analogs, which have been reported to selectively inhibit root growth, were tested by adding them to the nutrient solutions on day 10 of a 25 day growth test using spring wheat in hydroponic cultures. Growth and morphological changes is both shoot and root systems were evaluated. In no case was it possible to inhibit root growth without a comparable inhibition of shoot growth. It was concluded that this approach is unlikely to prove useful for wheat.

Rapid in vitro propagation system through shoot tip cultures of Vitex trifolia L.-an important multipurpose plant of the Pacific traditional Medicine.

Science.gov (United States)

Ahmed, Rafique; Anis, Mohammad

2014-07-01

A rapid and efficient plant propagation system through shoot tip explants was established in Vitex trifolia L., a medicinally important plant belonging to the family Verbenaceae. Multiple shoots were induced directly on Murashige and Skoog (MS) medium consisting of different cytokinins, 6-benzyladenine (BA), kinetin (Kin) and 2-isopentenyl adenine (2-iP), BA at an optimal concentration of 5.0 μM was most effective in inducing multiple shoots where 90 % explants responded with an average shoot number (4.4±0.1) and shoot length (2.0±0.1 cm) after 6 weeks of culture. Inclusion of NAA in the culture medium along with the optimum concentration of BA promoted a higher rate of shoot multiplication and length of the shoot, where 19.2±0.3 well-grown healthy shoots with an average shoot length of 4.4±0.1 cm were obtained on completion of 12 weeks culture period. Ex vitro rooting was achieved best directly in soilrite when basal portion of the shoots were treated with 500 μM indole-3-butyric acid for 15 min which was the most effective in inducing roots, as 95 % of the microshoots produced roots. Plantlets went through a hardening phase in a controlled plant growth chamber, prior to ex-vitro transfer. Micropropagated plants grew well, attained maturity and flowered with 92 % survival rate. The results of this study provide the first report on in vitro plant regeneration of Vitex trifolia L. using shoot tip explants.

Protocol optimization for in vitro shoot multiplication of Jackfruit ...

African Journals Online (AJOL)

Jemal

2017-01-11

Jan 11, 2017 ... Protocol optimization for in vitro shoot multiplication of ... shoot length and leaf number, whereby 2 mg/L BAP alone was found to be the best with a mean shoot .... Analysis of variance showed that the interaction between.

Experimental Salix shoot and root growth statistics on the alluvial sediment of a restored river corridor

Science.gov (United States)

Pasquale, N.; Perona, P.; Verones, F.; Francis, R.; Burlando, P.

2009-12-01

River restoration projects encompass not only the amelioration of flood protection but also the rehabilitation of the riverine ecosystem. However, the interactions and feedbacks between river hydrology, riparian vegetation and aquifer dynamics are still poorly understood. Vegetation interacts with river hydrology on multiple time scales. Hence, there is considerable interest in understanding the morphodynamics of restored river reaches in relation to the characteristics of vegetation that may colonize the bare sediment, and locally stabilize it by root anchoring. In this paper we document results from a number of ongoing experiments within the project RECORD (Restored CORridor Dynamics, sponsored by CCES - www.cces.ch - and Cantons Zurich and Thurgau, CH). In particular, we discuss both the above and below ground biomass growth dynamics of 1188 Salix cuttings (individual and group survival rate, growth of the longest shoots and number of branches and morphological root analysis) in relation to local river hydrodynamics. Cuttings were organized in square plots of different size and planted in spring 2009 on a gravel island of the restored river section of River Thur in Switzerland. By periodical monitoring the plots we obtained a detailed and quite unique set of data, including root statistics of uprooted samples derived from image analysis from a high-resolution scanner. Beyond describing the survival rate dynamics in relation to river hydrology, we show the nature and strength of correlations between island topography and cutting growth statistics. In particular, by root analysis and by comparing empirical histograms of the vertical root distribution vs satured water surface in the sediment, we show that main tropic responses on such environment are oxytropism, hydrotropism and thigmotropism. The main factor influencing the survival rate is naturally found in erosion by floods, of which we also give an interesting example that helps demonstrate the role of river

Shoot allometry and biomass productivity in poplar and willow varieties grown as short rotation coppice. Summary of results 1995-2000

Energy Technology Data Exchange (ETDEWEB)

Matthews, R.; Henshall, P.; Tubby, I.

2003-07-01

This report summarises the results of a 4 year study assessing shoot diameters and lengths using non-destructive measurements in order to establish allometric relationships between biomass and non-destructive measurements and also to provide estimates of increments for the development of a model of short rotation cultivation growth and yield. Details are given of the basic methodology and measurement conventions; the data preparation, quality assurance classification and storage; and shoot diameter and length assessments and allometry analyses.

Regeneration of okra ( Abelmoschus esculentus L.) via apical shoot ...

African Journals Online (AJOL)

Abelmoschus esculentus L. Monech) via apical shoot culture system. The study of apical shoot culture system was found effective for regeneration of apical shoots. The okra (A. esculentus L. Monech) N-550 line evolved at R&D, Nirmal Seeds Pvt. Ltd., ...

Effect of diesel generator exhaust pollutants on growth of Vinca ...

African Journals Online (AJOL)

The effects of exhaust pollutants of generator on root and shoot length, root and shoot weight, number of leaflets and leaf area, leaf and total plant dry weight of Vinca rosea and Ruellia tuberosa were studied. The treatment of exhaust pollutants produced significant effects on root, shoot growth, number of leaflet and leaf ...

Effect of BAP (6-benzylaminopurine on shoot induction in explants of brazilwood

Directory of Open Access Journals (Sweden)

Ana Katarina Oliveira Aragão

2011-09-01

Full Text Available The Brazilian Atlantic forest has been subjected to intense degradation, with only about 7% to 8% of its original area remaining today. This situation has raised concerns over the conservation of species threatened with extinction. In all, 276 tree and bush species are under threat, out of which this study chose to evaluate alternatives for protecting brazilwood ‘Pau-Brasil’ (Caesalpinia echinata Lam.. Most studies performed so far on this subject either evaluate the effect of cytokinins on induction of callogenesis or focus on improving cryopreservation methodologies. In an attempt to expand knowledge about biotechnological techniques enabling conservation of C. echinata, this work evaluated the effect of 6-benzylaminopurine (BAP and explant type on induction of shoots in brazilwood. To attain that, explants were inoculated into basic MS medium and into MS medium supplemented with 2.5 µM, 3.5 µM and 4.5 µM of BAP, and kept in a growth room for 40 days under controlled photoperiod and temperature conditions. A 2x4 factorial design was adopted, with three replicates. Analyzed variables included shoot percentage, callogenesis and oxidations, and means were compared by the Tukey test at the 5% probability level. Results showed a significant influence of BAP only on shoot induction, and of explant type on that variable and on other variables too. It was concluded that, under in vitro conditions, the nodal type of explant is more responsive to BAP action and that 2.5 µM is the recommended concentration for shoot induction in brazilwood.

Mass propagation of shoots of Stevia rebaudiana using a large scale bioreactor.

Science.gov (United States)

Akita, M; Shigeoka, T; Koizumi, Y; Kawamura, M

1994-01-01

A procedure for the mass propagation of multiple shoots of Stevia rebaudiana is described. Isolated shoot primordia were used as the inoculum to obtain clusters of shoot primordia. Such clusters were grown in a 500 liter bioreactor to obtain shoots. A total of 64.6 Kg of shoots were propagated from 460 g of the inoculated shoot primordia. These shoots were easily acclimatized in soil.

Effects of simulated root herbivory and fertilizer application on growth and biomass allocation in the clonal perennialSolidago canadensis.

Science.gov (United States)

Schmid, B; Miao, S L; Bazzaz, F A

1990-08-01

Compensatory growth in response to simulated belowground herbivory was studied in the old-field clonal perennialSolidago canadensis. We grew rootpruned plants and plants with intact root systems in soil with or without fertilizer. For individual current shoots (aerial shoot with rhizome and roots) and for whole clones the following predictions were tested: a) root removal is compensated by increased root growth, b) fertilizer application leads to increased allocation to aboveground plant organs and increased leaf turnover, c) effects of fertilizer application are reduced in rootpruned plants. When most roots (90%) were removed current shoots quickly restored equilibrium between above-and belowground parts by compensatory belowground growth whereas the whole clone responded with reduced aboveground growth. This suggests that parts of a clone which are shared by actively growing shoots act as a buffer that can be used as source of material for compensatory growth in response to herbivory. Current shoots increased aboveground mass and whole clones reduced belowground mass in response to fertilizer application, both leading to increased allocation to aboverground parts. Also with fertilizer application both root-pruned and not root-pruned plants increased leaf and shoot turnover. Unfertilized plants, whether rootpruned or not, showed practically no aboveground growth and very little leaf and shoot turnover. Effects of root removal were as severe or more severe under conditions of high as under conditions of low nutrients, suggesting that negative effects of belowground herbivory are not ameliorated by abundant nutrients. Root removal may negate some effects of fertilizer application on the growth of current shoots and whole clones.

Enhanced in vitro multiple shoot induction in elite Pakistani guava ...

African Journals Online (AJOL)

Elite guava (Psidium guajava L.) strains of cv. Safeda were explored in vitro for multiple shoot induction. Shoot induction was enhanced up to 83% with 3.5 to 4.25 shoots per single node cutting and shoot tip explants, respectively, using higher levels of benzyl amino purine (BAP) in Murashige and Skoog (MS) medium.

RAPD markers for screening shoot gall maker (Betousa stylophora Swinhoe tolerant genotypes of amla (Phyllanthus emblica L.

Directory of Open Access Journals (Sweden)

Sethuraman Thilaga

2017-12-01

Full Text Available Phyllanthus emblica Linn. is the most important medicinally useful tree crop in Asian Subcontinent and is severely infested by Betousa stylophora Swinhoe, known as shoot gall maker (SGM. This pest tunnels the shoots of seedlings and actively growing branches of trees and develops gall, leading to stunted growth, unusual branching and death of actively growing shoots. Our study revealed that trees possessing smooth bark were free from the attack of this pest than those with rough bark surface. Unfortunately, this character is not detectable either at seedling stage or during early growth of trees in the orchard. RAPD genetic fingerprinting of trees possessing smooth and rough bark revealed distinguishable and highly reproducible DNA banding pattern between the two genotypes. Of the 20 RAPD primers tested, five of them produced distinguishable RAPD bands between rough and smooth barked genotypes of P. emblica. Trees with smooth bark produced five unique RAPD bands with molecular weight ranging from 350 bp to 1500 bp and those with rough bark produced six RAPD bands (350 bp–650 bp to utilize these DNA bands as potential DNA marker for screening tolerant genotypes of this crop against SGM. The utility of this finding in genetic improvement of this tree crop against SGM is discussed.

Exposure to lead in South African shooting ranges

International Nuclear Information System (INIS)

Mathee, Angela; Jager, Pieter de; Naidoo, Shan; Naicker, Nisha

2017-01-01

Introduction: Lead exposure in shooting ranges has been under scrutiny for decades, but no information in this regard is available in respect of African settings, and in South Africa specifically. The aim of this study was to determine the blood lead levels in the users of randomly selected private shooting ranges in South Africa's Gauteng province. Methods: An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. Results: A total of 118 (87 shooters and 31 archers) were included in the analysis. Shooters had significantly higher blood lead levels (BLL) compared to archers with 36/85 (42.4%) of shooters versus 2/34 (5.9%) of archers found to have a BLL ≥10 μg/dl (p<0.001). Conclusion: Shooting ranges may constitute an import site of elevated exposure to lead. Improved ventilation, low levels of awareness of lead hazards, poor housekeeping, and inadequate personal hygiene facilities and practices at South African shooting ranges need urgent attention. - Highlights: • This is the first study, to our knowledge, of lead exposure in shooting ranges in an African setting. • This study indicates highly elevated lead exposure amongst the users of certain private shooting ranges in South Africa. • Lead exposure may be a serious, yet under-studied, source of adult lead exposure in South Africa, and possibly elsewhere on the African continent.

Exposure to lead in South African shooting ranges

Energy Technology Data Exchange (ETDEWEB)

Mathee, Angela [South African Medical Research Council, Environment & Health Research Unit, PO Box 87373, Houghton 2041 (South Africa); University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); University of Johannesburg (Environmental Health Department, Faculty of Health Sciences), PO Box 524, Auckland Park, Johannesburg 2006 (South Africa); Jager, Pieter de [University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); National Health Laboratory Service (Epidemiology and Surveillance Unit, National Institute for Occupational Health), PO Box 4788, Johannesburg 2000 (South Africa); Naidoo, Shan [University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); Naicker, Nisha [South African Medical Research Council, Environment & Health Research Unit, PO Box 87373, Houghton 2041 (South Africa); University of the Witwatersrand, School of Public Health, PO Box Wits, Johannesburg 2050 (South Africa); University of Johannesburg, Environmental Health Department, Faculty of Health Sciences, PO Box 524, Auckland Park, Johannesburg 2006 (South Africa)

2017-02-15

Introduction: Lead exposure in shooting ranges has been under scrutiny for decades, but no information in this regard is available in respect of African settings, and in South Africa specifically. The aim of this study was to determine the blood lead levels in the users of randomly selected private shooting ranges in South Africa's Gauteng province. Methods: An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. Results: A total of 118 (87 shooters and 31 archers) were included in the analysis. Shooters had significantly higher blood lead levels (BLL) compared to archers with 36/85 (42.4%) of shooters versus 2/34 (5.9%) of archers found to have a BLL ≥10 μg/dl (p<0.001). Conclusion: Shooting ranges may constitute an import site of elevated exposure to lead. Improved ventilation, low levels of awareness of lead hazards, poor housekeeping, and inadequate personal hygiene facilities and practices at South African shooting ranges need urgent attention. - Highlights: • This is the first study, to our knowledge, of lead exposure in shooting ranges in an African setting. • This study indicates highly elevated lead exposure amongst the users of certain private shooting ranges in South Africa. • Lead exposure may be a serious, yet under-studied, source of adult lead exposure in South Africa, and possibly elsewhere on the African continent.

The Level of Vision Necessary for Competitive Performance in Rifle Shooting: Setting the Standards for Paralympic Shooting With Vision Impairment

Directory of Open Access Journals (Sweden)

Peter M Allen

2016-11-01

Full Text Available The aim of this study was to investigate the level of vision impairment that would reduce performance in shooting; to guide development of entry criteria to visually impaired (VI shooting. Nineteen international-level shooters without vision impairment took part in the study. Participants shot an air rifle, while standing, towards a regulation target placed at the end of a 10m shooting range. Cambridge simulation glasses were used to simulate six different levels of vision impairment. Visual acuity (VA and contrast sensitivity (CS were assessed along with shooting performance in each of seven conditions of simulated impairment and compared to that with habitual vision. Shooting performance was evaluated by calculating each individual’s average score in every level of simulated vision impairment and normalising this score by expressing it as a percentage of the baseline performance achieved with habitual vision. Receiver Operating Characteristic (ROC curves were constructed to evaluate the ability of different VA and CS cut-off criteria to appropriately classify these athletes as achieving ‘expected’ or ‘below expected’ shooting results based on their performance with different levels of VA and CS. Shooting performance remained relatively unaffected by mild decreases in VA and CS, but quickly deteriorated with more moderate losses. The ability of visual function measurements to classify shooting performance was good, with 78% of performances appropriately classified using a cut-off of 0.53 logMAR and 74% appropriately classified using a cut-off of 0.83 logCS. The current inclusion criteria for VI shooting (1.0 logMAR is conservative, maximising the chance of including only those with an impairment that does impact performance, but potentially excluding some who do have a genuine impairment in the sport. A lower level of impairment would include more athletes who do have a genuine impairment but would potentially include those who do not

Shoot and root morphogenesis from Eucalyptus grandis x urophylla ...

African Journals Online (AJOL)

Eucalyptus grandis x urophylla plantlets were regenerated via indirect organogenesis. Histological assessment of their development focused on identifying the calli, the differentiation of shoots from the calli and the shoot-root junction from the nascent shoots. Vascular tissue formation within the callus preceded that of ...

Antioxidant compounds in Salvia officinalis L. shoot and hairy root cultures in the nutrient sprinkle bioreactor

Directory of Open Access Journals (Sweden)

Izabela Grzegorczyk

2011-01-01

Full Text Available The study focused on the production of compounds with antioxidant activity in hairy root and shoot cultures of Salvia officinalis grown in laboratory-scale sprinkle nutrient bioreactors. HPLC analysis showed that production of rosmarinic acid in transformed roots (34.65 ±1.07 mg l-1 was higher that in shoot culture (26.24 ±0.48 mg l-1. In the latter diterpenoids: carnosic acid (1.74 ±0.02 mg l-1 and carnosol (1.34 ±0.01 mg l-1 were also found. Biomass accumulation after a growth period in the bioreactor was also studied. An 18-fold increase in hairy root biomass was recorded after 40 days of culture. In sage shoot culture, biomass increased 43 times after 21 days of bioreactor run. The current operating conditions of the bioreactor were not suitable for the propagation of Salvia officinalis mainly due to the hyperhydricity problem of leaves and stems.

Structure–Function Relationships in Highly Modified Shoots of Cactaceae

Science.gov (United States)

MAUSETH, JAMES D.

2006-01-01

• Background and Aims Cacti are extremely diverse structurally and ecologically, and so modified as to be intimidating to many biologists. Yet all have the same organization as most dicots, none differs fundamentally from Arabidopsis or other model plants. This review explains cactus shoot structure, discusses relationships between structure, ecology, development and evolution, and indicates areas where research on cacti is necessary to test general theories of morphogenesis. • Scope Cactus leaves are diverse; all cacti have foliage leaves; many intermediate stages in evolutionary reduction of leaves are still present; floral shoots often have large, complex leaves whereas vegetative shoots have microscopic leaves. Spines are modified bud scales, some secrete sugar as extra-floral nectaries. Many cacti have juvenile/adult phases in which the flowering adult phase (a cephalium) differs greatly from the juvenile; in some, one side of a shoot becomes adult, all other sides continue to grow as the juvenile phase. Flowers are inverted: the exterior of a cactus ‘flower’ is a hollow vegetative shoot with internodes, nodes, leaves and spines, whereas floral organs occur inside, with petals physically above stamens. Many cacti have cortical bundles vascularizing the cortex, however broad it evolves to be, thus keeping surface tissues alive. Great width results in great weight of weak parenchymatous shoots, correlated with reduced branching. Reduced numbers of shoot apices is compensated by great increases in number of meristematic cells within individual SAMs. Ribs and tubercles allow shoots to swell without tearing during wet seasons. Shoot epidermis and cortex cells live and function for decades then convert to cork cambium. Many modifications permit water storage within cactus wood itself, adjacent to vessels. PMID:16820405

Structure-function relationships in highly modified shoots of cactaceae.

Science.gov (United States)

Mauseth, James D

2006-11-01

Cacti are extremely diverse structurally and ecologically, and so modified as to be intimidating to many biologists. Yet all have the same organization as most dicots, none differs fundamentally from Arabidopsis or other model plants. This review explains cactus shoot structure, discusses relationships between structure, ecology, development and evolution, and indicates areas where research on cacti is necessary to test general theories of morphogenesis. Cactus leaves are diverse; all cacti have foliage leaves; many intermediate stages in evolutionary reduction of leaves are still present; floral shoots often have large, complex leaves whereas vegetative shoots have microscopic leaves. Spines are modified bud scales, some secrete sugar as extra-floral nectaries. Many cacti have juvenile/adult phases in which the flowering adult phase (a cephalium) differs greatly from the juvenile; in some, one side of a shoot becomes adult, all other sides continue to grow as the juvenile phase. Flowers are inverted: the exterior of a cactus 'flower' is a hollow vegetative shoot with internodes, nodes, leaves and spines, whereas floral organs occur inside, with petals physically above stamens. Many cacti have cortical bundles vascularizing the cortex, however broad it evolves to be, thus keeping surface tissues alive. Great width results in great weight of weak parenchymatous shoots, correlated with reduced branching. Reduced numbers of shoot apices is compensated by great increases in number of meristematic cells within individual SAMs. Ribs and tubercles allow shoots to swell without tearing during wet seasons. Shoot epidermis and cortex cells live and function for decades then convert to cork cambium. Many modifications permit water storage within cactus wood itself, adjacent to vessels.

Coral growth rates revisited after 31 years: what is causing lower extension rates in Acropora palmata?

NARCIS (Netherlands)

Bak, R.P.M.; Nieuwland, G.; Meesters, H.W.G.

2009-01-01

Linear extension of branches in the same Acropora palmata (Lamarck, 1816) population in Curaçao was measured, employing exactly the same methods, in 1971-1973 and in 2002-2004, and the resulting coral growth rates are compared. Linear growth shows the same pattern over seasons in both periods with

Millet's Shooting Stars

Science.gov (United States)

Beech, M.

1988-12-01

In this essay two paintings by the French artist Jean-Francois Millet are described. These paintings, Les Etoiles Filantes and Nuit Etoilée are particularly interesting since they demonstrate the rare artistic employment of the shooting-star image and metaphor.

Effect of sodium chloride on the growth and fruiting of Cabernet Sauvignon vines

Energy Technology Data Exchange (ETDEWEB)

Hawker, J.S.; Walker, R.R.

1978-01-01

Sodium chloride was supplied to rooted cuttings of Vitis vinifera cv Cabernet Sauvignon grown in a porous growth medium at concentrations of 0, 20, 50 and 75 mM. Shoot and leaf growth and berry set and development were reduced by NaCl, the severity of the effects depending on both NaCl concentration and the age of the plants receiving the treatment. Shoots were not affected by 20 mM NaCl supplied 10 days after flowering but 50 and 75 mM NaCl caused severe stunting of shoots and 75 mM NaCl had a marked effect on berry growth and development. When NaCl was supplied to vines 10 days before flowering, 20, 50 and 75 mM NaCl inhibited shoot growth and reduced berry size and sugar content. Although NaCl caused a decrease in the rate of growth of both leaves and berries, no changes in invertase or pectin methylesterase activities were found in these organs from plants supplied with NaCl.

Multiple shoot regeneration of cotton (Gossypium hirsutum L.) via ...

African Journals Online (AJOL)

user

2011-03-14

Mar 14, 2011 ... Induction of multiple shoots of cotton (Gossypium hirsutum L.) plant in two commercial varieties (Sahel and Varamin) using shoot apex was done. Explants were isolated from 3 - 4 days old seedlings, then they were cultured on a shoot induction media, modified MS nutrient agar with combinations: 1- ...

Production of polyploids from cultured shoot tips of Eucalyptus ...

African Journals Online (AJOL)

Polyploids from cultured shoot tips of Eucalyptus globulus were produced by treatment with colchicine. Results showed that the combination of 0.5% colchicine and treating multiple shoot clumps for 4 days was the most appropriate conditions for E. globulus polyploidy induction and the effect of the use of multiple shoot ...

Shooting mechanisms in Nature : A systematic review

NARCIS (Netherlands)

Sakes, A.; van der Wiel, M.; Henselmans, P.W.J.; van Leeuwen, J.L.; Dodou, D.; Breedveld, P.

2016-01-01

Background
In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these

Shoot organogenesis in oleaster (Elaeagnus angustifolia L.)

African Journals Online (AJOL)

STORAGESEVER

2009-02-04

Feb 4, 2009 ... Regenerated plantlets were acclimatized and successfully transplanted to soil. Key words: shoot organogenesis, callus, ... saline and alkaline soils (Economou and Maloupa, 1995). Its fruits have been used as a .... cally inert compounds as reported by Kaminek (1992). Direct shoot organogenesis without ...

Cell fate regulation in the shoot meristem.

Science.gov (United States)

Laux, T; Mayer, K F

1998-04-01

The shoot meristem is a proliferative centre containing pluripotent stem cells that are the ultimate source of all cells and organs continuously added to the growing shoot. The progeny of the stem cells have two developmental options, either to renew the stem cell population or to leave the meristem and to differentiate, possibly according to signals from more mature tissue. The destiny of each cell depends on its position within the dynamic shoot meristem. Genetic data suggest a simple model in which graded positional information is provided by antagonistic gene functions and is interpreted by genes which regulate cell fate.

Priorities for Extension.

Science.gov (United States)

Hayward, J. A.

Agricultural extension is one component in an array including research, training, education, marketing, international trade, etc. which develop together to bring about growth, and sustained growth determines the priorities for extension. These priorities depend inevitably on the stage of development of a country or region, and on the current…

Influence of salicylic acid on growth and some biochemical ...

African Journals Online (AJOL)

Yomi

2012-01-10

Jan 10, 2012 ... Our results show that in plants not sprayed with salicylic acid but treated with NaCl, shoot length, wet weight of shoot and root, ... Photosynthesis and cell growth can be affected by ..... Protection of plasma membrane of onion.

Effect of temperature on development and growth potential of axillary buds in roses

NARCIS (Netherlands)

Marcelis-van Acker, C.A.M.

1995-01-01

The effect of temperature during axillary bud formation on axillary bud development and subsequent shoot growth was investigated. Growth potential of the axillary buds was studied either in situ, by pruning the parent shoot above the bud, or in isolation, by grafting the bud or by culturing the bud

Accuracy of Skill Performance in the Basketball Free Throw Shooting

Directory of Open Access Journals (Sweden)

Igawa Shoji

2011-12-01

Full Text Available The purpose of this study were to investigates how timing of shot of skilled player and assess performance accuracy of free throw shooting. Ten college students participated in this study (5 skilled players, and 5 naïve participants aged 18-23 years. They performed free throw shooting at 10 times. Shooting seen was recorded three cameras and analyzed shooting successful rate, off-target distance (the distance between the basketball through point and the center of the goal and shot timing. Shot timing was not significant difference. Shooting successful rate of skilled players was higher than unskilled players. Offtarget distance of skilled players was significant smaller than naive player. Consequently, skilled player is possible to aim at the center of the goal and shooting near the center of goal.

Journalism and School Shootings in Finland 2007 -2008

OpenAIRE

Raittila, Pentti; Koljonen, Kari; Väliverronen, Jari

2010-01-01

Two school shootings in Finland (Jokela in 2007 and Kauhajoki in 2008) resulted in the death of 20 people, and they shook not only the foundations of Finnish society but also of the profession that reported about the tragedies. This report is based on research conducted on school shootings at the University of Tampere Journalism Research and Development Centre between 2008 and 2009. The analysis concentrates on both the journalistic texts published on the shootings and journalists' actions...

Effects of thidiazuron and paclobutrazol on regeneration potential of tulip flower stalk explants in vitro and subsequent shoot multiplication

Directory of Open Access Journals (Sweden)

Małgorzata Podwyszyńska

2011-01-01

Full Text Available The effects of TDZ and paclobutrazol on the primary regeneration on tulip flower stalk explants of six cultivars and subsequent shoot multiplication were examined. Explants, flower stalk slices, were excised from cooled and subsequently forced bulbs. The explants were incubated for two months in darkness on medium containing NAA and cytokinins, 2iP and BAP, as control, or TDZ (0.5-4 mg l-1 and paclobutrazol (0.05-0.4 mg l-1. Then, the regenerating explants were subcultured on medium with TDZ and NAA applied at low concentrations. Different regeneration capabilities were found depending on cultivar and growth regulators. The percentage of explants forming leaf-like structures ranged, on the control medium, from 80% in 'Blue Parrot' and 'Prominence' to below 30% in 'Apeldoorn' and 'Mirjoran'. TDZ, applied at optimum for each cultivar concentration, greatly increased the regeneration potential up to 70-100%. Paclobutrazol, added to the TDZ-containing medium, significantly enhanced the response of explants, resulting in high numbers of leaf-like structures formed per explant (13.7-22.8. The structures developed gradually into characteristic forms: the growing up cotyledonary leaf, the probable root primordium formed at its base, the growing downwards stolon and the shoot meristem developed finely on its tip. It is suggested that such primary regeneration may have a nature of somatic embryogenesis. Then, the adventitious shoots developed and formed clusters, which were divided into 2-3 smaller ones every two months. The growth regulators, used at initial stage, markedly influenced subsequent shoot multiplication. Thus, the most intensive shoot formation was noted with TDZ at concentrations of 0.5-2 mg l-1 and paclobutrazol of 0.05-0.1 mg l-1.

Defense.gov Special Report: Fort Hood Shooting

Science.gov (United States)

identify possible insider threats, Army Secretary John M. McHugh told lawmakers. Story Obama: Soldiers ," Army Secretary John M. McHugh told lawmakers. Story President Praises Swift Response to Fort Hood Remarks on Fort Hood Shooting at White House McHugh, Odierno Address Fort Hood Shooting Before Congress

Lead pollution of shooting range soils | Sehube | South African ...

African Journals Online (AJOL)

Atotal of eight military shooting ranges were used for this study. Soil samples were collected at each of the eight shooting ranges at the berm, target line, 50 and 100 m from berm. In all of the shooting ranges investigated the highest total lead (Pb) concentrations were found in the bermsoils. Elevated Pb concentrations of 38 ...

Effect of lanthanum on rooting of in vitro regenerated shoots of Saussurea involucrata Kar. et Kir.

Science.gov (United States)

Guo, Bin; Xu, Ling-Ling; Guan, Zhen-Jun; Wei, Ya-Hui

2012-06-01

In present study, the effect of lanthanum (La) on the rooting of regenerated shoots of Saussurea involucrata Kar. et Kir was analyzed. Rooting occurred from regenerated shoots inoculated on a medium supplemented with La, the plant rooting hormone indole-3-acetic acid (IAA), or both La and IAA together. The highest rooting efficiency (96%), root number/shoot (8.5), and root length (63 mm) were recorded in shoots cultured on medium containing 2.5 μM IAA combined with 100 μM La(3+). In order to elucidate the mechanism of rooting enhancement by La, we examined dynamic changes in antioxidant enzyme activities in plant tissue over time in culture. We found that the activities of peroxidase (POX) and superoxide dismutase (SOD) were significantly higher in plant tissue cultured in IAA plus La than in La or IAA alone. At the same time, the highest H(2)O(2) content was detected in plant tissue in the presence of 2.5 μM IAA plus 100 μM La(3+). In light of these data and previous results, we speculate that La enhanced IAA-induced rooting by acting as a mild abiotic stress to stimulate POX and SOD activities in plant cells. Then, IAA reacted with oxygen and POX to form the ternary complex enzyme-IAA-O(2) that dissociated into IAA radicals and O(2)(-). Subsequently, IAA-induced O(2)(-) readily converted to hydroxyl radical (HO·) via SOD-catalyzed dismutation. Finally, cell wall loosening and cell elongation occurred as a consequence of HO-dependent scission of wall components, leading to root growth. The treatment of IAA combined with La resulted in the highest plantlet survival (80%) compared to single treatments with IAA or La alone. These data suggest that rare earth elements enhance root morphogenesis and the growth of S. involucrata.

Contagion in Mass Killings and School Shootings.

Directory of Open Access Journals (Sweden)

Sherry Towers

Full Text Available Several past studies have found that media reports of suicides and homicides appear to subsequently increase the incidence of similar events in the community, apparently due to the coverage planting the seeds of ideation in at-risk individuals to commit similar acts.Here we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings (incidents with four or more people killed. We fit a contagion model to recent data sets related to such incidents in the US, with terms that take into account the fact that a school shooting or mass murder may temporarily increase the probability of a similar event in the immediate future, by assuming an exponential decay in contagiousness after an event.We find significant evidence that mass killings involving firearms are incented by similar events in the immediate past. On average, this temporary increase in probability lasts 13 days, and each incident incites at least 0.30 new incidents (p = 0.0015. We also find significant evidence of contagion in school shootings, for which an incident is contagious for an average of 13 days, and incites an average of at least 0.22 new incidents (p = 0.0001. All p-values are assessed based on a likelihood ratio test comparing the likelihood of a contagion model to that of a null model with no contagion. On average, mass killings involving firearms occur approximately every two weeks in the US, while school shootings occur on average monthly. We find that state prevalence of firearm ownership is significantly associated with the state incidence of mass killings with firearms, school shootings, and mass shootings.

Contagion in Mass Killings and School Shootings.

Science.gov (United States)

Towers, Sherry; Gomez-Lievano, Andres; Khan, Maryam; Mubayi, Anuj; Castillo-Chavez, Carlos

2015-01-01

Several past studies have found that media reports of suicides and homicides appear to subsequently increase the incidence of similar events in the community, apparently due to the coverage planting the seeds of ideation in at-risk individuals to commit similar acts. Here we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings (incidents with four or more people killed). We fit a contagion model to recent data sets related to such incidents in the US, with terms that take into account the fact that a school shooting or mass murder may temporarily increase the probability of a similar event in the immediate future, by assuming an exponential decay in contagiousness after an event. We find significant evidence that mass killings involving firearms are incented by similar events in the immediate past. On average, this temporary increase in probability lasts 13 days, and each incident incites at least 0.30 new incidents (p = 0.0015). We also find significant evidence of contagion in school shootings, for which an incident is contagious for an average of 13 days, and incites an average of at least 0.22 new incidents (p = 0.0001). All p-values are assessed based on a likelihood ratio test comparing the likelihood of a contagion model to that of a null model with no contagion. On average, mass killings involving firearms occur approximately every two weeks in the US, while school shootings occur on average monthly. We find that state prevalence of firearm ownership is significantly associated with the state incidence of mass killings with firearms, school shootings, and mass shootings.

The effect of triacontanol on shoot multiplication and production of antioxidant compounds in shoot cultures of Salvia officinalis L.

Directory of Open Access Journals (Sweden)

Izabela Grzegorczyk

2011-01-01

Full Text Available This report describes the effect of triacontanol on shoot multiplication and production of antioxidant compounds (carnosic acid, carnosol and rosmarinic acid in S. officinalis cultures grown on MS basal medium (agar solidified medium supplemented with 0.1 mg l-1 IAA, 0.45 mg l-1 BAP. It was found that shoot proliferation significantly increased when triacontanol at concentrations of 5, 10 or 20 µg l-1 was added to the medium. HPLC analysis of acetone and methanolic extracts of sage shoots showed that the production of diterpenoids, carnosic acid/carnosol ratio, as well as, contents of rosmarinic acid were also affected by the treatment with triacontanol. The highest stimulation effect of triacontanol was observed on the production of carnosol, where the treatment with 20 µg l l-1 increased the content of this diterpenoid 4.5-fold compared to that in the control (sage shoots growing on MS basal medium, only.

Australian Mass Shootings: An Analysis of Incidents and Offenders.

Science.gov (United States)

McPhedran, Samara

2017-06-01

Mass shooting events are relatively underresearched, and most study comes from the United States. Despite significant international interest, little is known about other countries' experiences of these events. The current study examines Australian mass shooting incidents and offenders, with emphasis on mental illness, life strains, and offenders' life histories. Australia had 14 mass shootings between 1964 and 2014. Most offenders experienced acute life stressors and/or chronic strains leading up to the event; however, diagnosed mental illness was less commonly documented. These observations provide new information about mass shooting incidents and offenders, and can help to inform international policy development.

Development and validation of extensive growth and growth boundary models for psychrotolerant pseudomonads in seafood, meat and vegetable products

DEFF Research Database (Denmark)

Martinez Rios, Veronica; Dalgaard, Paw

Extensive growth and growth boundary models were developed and validated for psychrotolerant pseudomonads growing in seafood, meat and vegetable products. The new models were developed by expanding anexisting cardinal parameter-type model for growth of pseudomonads in milk (Martinez-Rios et al......, when observed and predicted μmax -values were compared. Thus, on average μmax -values for seafood and meat products were overestimated by 14%. Additionally, the reference growth rate parameter μref25˚C was calibrated by fitting the model to 21 μmax -values in vegetable products. This resulted in a μref......25˚C -value of 0.54 1/h. The calibrated vegetable model wassuccessfully validated using 51 μmax -values for psychrotolerant pseudomonads in vegetables. Average bias and accuracy factor values of 1.24 and 1.38 were obtained, respectively. Lag time models were developed by using relative lag times from...

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)

Salim, S.; Rashid, A.

2014-01-01

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)

Shooting stars

International Nuclear Information System (INIS)

Maurette, M.; Hammer, C.

1985-01-01

A shooting star passage -even a star shower- can be sometimes easily seen during moonless black night. They represent the partial volatilization in earth atmosphere of meteorites or micrometeorites reduced in cosmic dusts. Everywhere on earth, these star dusts are searched to be gathered. This research made one year ago on the Greenland ice-cap is this article object; orbit gathering projects are also presented [fr

thidiazuron improves adventitious bud and shoot regeneration

African Journals Online (AJOL)

Prof. Adipala Ekwamu

Induction of adventitious buds and shoots from intact leaves and stem internode segments of two recalcitrant. Ugandan sweetpotato (Ipomoea batatas L.) cultivars was investigated in vitro on Murashige and Skoog (MS) medium, supplemented with 3 different levels (0.5, 2.0 and 4.0 µM) of Thidiazuron (TDZ). Shoots were.

Citrus flush shoot ontogeny modulates biotic potential of Diaphorina citri.

Science.gov (United States)

Cifuentes-Arenas, Juan Camilo; de Goes, António; de Miranda, Marcelo Pedreira; Beattie, George Andrew Charles; Lopes, Silvio Aparecido

2018-01-01

The biology and behaviour of the psyllid Diaphorina citri Kuwayama (Hemiptera: Sternorrhyncha: Liviidae), the major insect vector of bacteria associated with huanglongbing, have been extensively studied with respect to host preferences, thermal requirements, and responses to visual and chemical volatile stimuli. However, development of the psyllid in relation to the ontogeny of immature citrus flush growth has not been clearly defined or illustrated. Such information is important for determining the timing and frequency of measures used to minimize populations of the psyllid in orchards and spread of HLB. Our objective was to study how flush ontogeny influences the biotic potential of the psyllid. We divided citrus flush growth into six stages within four developmental phases: emergence (V1), development (V2 and V3), maturation (V4 and V5), and dormancy (V6). Diaphorina citri oviposition and nymph development were assessed on all flush stages in a temperature controlled room, and in a screen-house in which ambient temperatures varied. Our results show that biotic potential of Diaphorina citri is not a matter of the size or the age of the flushes (days after budbreak), but the developmental stage within its ontogeny. Females laid eggs on flush V1 to V5 only, with the time needed to commence oviposition increasing with the increasing in flush age. Stages V1, V2 and V3 were most suitable for oviposition, nymph survival and development, and adult emergence, which showed evidence of protandry. Flush shoots at emerging and developmental phases should be the focus of any chemical or biological control strategy to reduce the biotic potential of D. citri, to protect citrus tree from Liberibacter infection and to minimize HLB dissemination.

School shootings during 2013-2015 in the USA.

Science.gov (United States)

Kalesan, Bindu; Lagast, Kinan; Villarreal, Marcos; Pino, Elizabeth; Fagan, Jeffrey; Galea, Sandro

2017-10-01

Data on the factors associated with school shootings in the USA are limited. The public conversation has often suggested several factors that may be linked to these events, however with little empirical support. Aiming to fill this gap, we describe the characteristics of school shooting incidents in the USA between 2013 and 2015 and explore whether four factors that represent domains of firearm policy, educational policy and epidemiological risk factors for intentional firearm injuries-background check (BC) policies, per capita mental health expenditures (MHE), K-12 education expenditure (KEE) and urbanicity-were associated with school shootings during this period. We searched LexisNexis, a newspaper and broadcast media databases for school shooting incidents from 1 January 2013 to 31 December 2015. Presence of BC laws was extracted from legal information in LexisNexis. State-level covariates of per capita MHE (2013), KEE (2013) and urbanicity (2010) rates were obtained from publicly available data sources. We used negative binomial regression models accounting for clustering by state to explore unadjusted associations between the BC laws, state-level covariates and school shootings to report IRR and 95% CI. We documented 154 school shootings (35, 55 and 64 each year). In unadjusted models, BC for firearm purchase (IRR=0.55, 95% CI 0.39 to 0.76), ammunition purchase (IRR=0.11, 95% CI 0.05 to 0.27), log per capita MHE (IRR=0.58, 95% CI 0.37 to 0.90), log per-capita KEE (IRR=0.09, 9% CI 0.02 to 0.29) and urbanicity (IRR=0.97, 95% CI 0.96 to 0.99) were associated with school shooting. School shootings are less likely in states with BC laws, higher MHE and KEE, and with greater per cent urban population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Early changes in shoot transcriptome of rice in response to Rhodotorula mucilaginosa JGTA-S1

Directory of Open Access Journals (Sweden)

Chinmay Saha

2015-12-01

Full Text Available Yeasts of Rhodotorula genus have been reported to show endophytic colonization in different plants. Some of the Rhodotorula species are found to exhibit plant growth promoting activities and also have been reported to protect plants against invading pathogens. A yeast strain closely related to Rhodotorula mucilaginosa was isolated from the endosphere of Typha angustifolia collected from a Uranium mine. A microarray analysis was performed to investigate the early changes in rice shoot transcripts in response to this yeast (R. mucilaginosa JGTA-S1. Transcriptional changes were monitored in 6 h and 24 h treated rice plant shoots as compared to 0 h control. The microarray data has been submitted to the NCBI GEO repository under the accession number of GSE64321.

Growth responses, biomass partitioning, and nitrogen isotopes of prairie legumes in response to elevated temperature and varying nitrogen source in a growth chamber experiment.

Science.gov (United States)

Whittington, Heather R; Deede, Laura; Powers, Jennifer S

2012-05-01

Because legumes can add nitrogen (N) to ecosystems through symbiotic fixation, they play important roles in many plant communities, such as prairies and grasslands. However, very little research has examined the effect of projected climate change on legume growth and function. Our goal was to study the effects of temperature on growth, nodulation, and N chemistry of prairie legumes and determine whether these effects are mediated by source of N. We grew seedlings of Amorpha canescens, Dalea purpurea, Lespedeza capitata, and Lupinus perennis at 25/20°C (day/night) or 28/23°C with and without rhizobia and mineral N in controlled-environment growth chambers. Biomass, leaf area, nodule number and mass, and shoot N concentration and δ(15)N values were measured after 12 wk of growth. Both temperature and N-source affected responses in a species-specific manner. Lespedeza showed increased growth and higher shoot N content at 28°C. Lupinus showed decreases in nodulation and lower shoot N concentration at 28°C. The effect of temperature on shoot N concentration occurred only in individuals whose sole N source was N(2)-fixation, but there was no effect of temperature on δ(15)N values in these plants. Elevated temperature enhanced seedling growth of some species, while inhibiting nodulation in another. Temperature-induced shifts in legume composition or nitrogen dynamics may be another potential mechanism through which climate change affects unmanaged ecosystems.

The Mental Health Consequences of Mass Shootings.

Science.gov (United States)

Lowe, Sarah R; Galea, Sandro

2017-01-01

Mass shooting episodes have increased over recent decades and received substantial media coverage. Despite the potentially widespread and increasing mental health impact of mass shootings, no efforts to our knowledge have been made to review the empirical literature on this topic. We identified 49 peer-reviewed articles, comprised of 27 independent samples in the aftermath of 15 mass shooting incidents. Based on our review, we concluded that mass shootings are associated with a variety of adverse psychological outcomes in survivors and members of affected communities. Less is known about the psychological effects of mass shootings on indirectly exposed populations; however, there is evidence that such events lead to at least short-term increases in fears and declines in perceived safety. A variety of risk factors for adverse psychological outcomes have been identified, including demographic and pre-incident characteristics (e.g., female gender and pre-incident psychological symptoms), event exposure (e.g., greater proximity to the attack and acquaintance with the deceased), and fewer psychosocial resources (e.g., emotion regulation difficulties and lower social support). Further research that draws on pre-incident and longitudinal data will yield important insights into the processes that exacerbate or sustain post-incident psychological symptoms over time and provide important information for crisis preparedness and post-incident mental health interventions. © The Author(s) 2015.

Seasonal growth dynamics of the seagrass Zostera caulescens on the eastern coast of Korea

Science.gov (United States)

Kim, Jong-Hyeob; Park, Sang Hoon; Kim, Young Kyun; Kim, Seung Hyeon; Park, Jung-Im; Lee, Kun-Seop

2014-12-01

Zostera caulescens is an endemic seagrass species in Northeastern Asia. Estimated distributional area of this species is approximately 1-5 km2 on the coasts of Korea. Because Z. caulescens has a very limited distribution, the growth dynamics of Z. caulescens is little known in the coastal waters of Korea. In the present study, we investigated the growth dynamics of Z. caulescens in relation to coincident measurements of environmental factors, such as underwater irradiance, water temperature, and nutrient availability. The study was conducted on a monotypic meadow of Z. caulescens in Uljin on the eastern coast of Korea from September 2011 to September 2012. Shoot density and biomass of Z. caulescens showed distinct seasonal variations, and exhibited strong correlations with water temperature suggesting that the seasonal growth of this species was regulated by water temperature. Shoot density and biomass rapidly decreased during the high water temperature period in summer, and thus Z. caulescens is considered a cold water adapted species like other temperate seagrass species on coasts of Korea. Biomass of photosynthetic leaf tissues on reproductive shoots was approximately 4 times higher than that on vegetative shoots. The height of reproductive shoots ranged from 1.2 m in February 2012 to 3.2 m in August 2012, whereas the height of vegetative shoots was usually less than 1.0 m. Leaf tissues on reproductive shoots probably received much more light for photosynthesis than those on vegetative shoots. Thus, reproductive shoots may play an important role in total production of Z. caulescens.

Mass Shootings: The Role of the Media in Promoting Generalized Imitation.

Science.gov (United States)

Meindl, James N; Ivy, Jonathan W

2017-03-01

Mass shootings are a particular problem in the United States, with one mass shooting occurring approximately every 12.5 days. Recently a "contagion" effect has been suggested wherein the occurrence of one mass shooting increases the likelihood of another mass shooting occurring in the near future. Although contagion is a convenient metaphor used to describe the temporal spread of a behavior, it does not explain how the behavior spreads. Generalized imitation is proposed as a better model to explain how one person's behavior can influence another person to engage in similar behavior. Here we provide an overview of generalized imitation and discuss how the way in which the media report a mass shooting can increase the likelihood of another shooting event. Also, we propose media reporting guidelines to minimize imitation and further decrease the likelihood of a mass shooting.

In vitro propagation of peanut (Arachis hypogaea L.) by shoot tip culture.

Science.gov (United States)

Ozudogru, Elif Aylin; Kaya, Ergun; Lambardi, Maurizio

2013-01-01

Peanut (Arachis hypogaea L.), also known as groundnut, is the most important species of Arachis genus, originating from Brazil and Peru. Peanut seeds contain high seed oil, proteins, amino acids, and vitamin E, and are consumed worldwide as edible nut, peanut butter, or candy, and peanut oil extracted from the seeds. The meal remaining after oil extraction is also used for animal feed. However, its narrow germplasm base, together with susceptibility to diseases, pathogens, and weeds, decreases yield and seed quality and causes great economic losses annually. Hence, the optimization of efficient in vitro propagation procedures would be highly effective for peanut propagation, as it would raise yield and improve seed quality and flavor. Earlier reports on traditional micropropagation methods, based on axillary bud proliferation which guarantees the multiplication of true-to-type plants, are still limited. This chapter describes a micropropagation protocol to improve multiple shoot formation from shoot-tip explants by using AgNO(3) in combination with plant growth regulators.

Variable Levels of Glutathione S-Transferases Are Responsible for the Differential Tolerance to Metolachlor between Maize (Zea mays) Shoots and Roots.

Science.gov (United States)

Li, Dongzhi; Xu, Li; Pang, Sen; Liu, Zhiqian; Wang, Kai; Wang, Chengju

2017-01-11

Glutathione S-transferases (GSTs) play important roles in herbicide tolerance. However, studies on GST function in herbicide tolerance among plant tissues are still lacking. To explore the mechanism of metolachlor tolerance difference between maize shoots and roots, the effects of metolachlor on growth, GST activity, and the expression of the entire GST gene family were investigated. It was found that this differential tolerance to metolachlor was correlated with contrasting GST activity between the two tissues and can be eliminated by a GST inhibitor. An in vitro metolachlor-glutathione conjugation assay confirmed that the transformation of metolachlor is 2-fold faster in roots than in shoots. The expression analysis of the GST gene family revealed that most GST genes are expressed much higher in roots than shoots, both in control and in metolachlor-treated plants. Taken together, higher level expression of most GST genes, leading to higher GST activity and faster herbicide transformation, appears to be responsible for the higher tolerance to metolachlor of maize roots than shoots.

[Influence of genotype, explant type and component of culture medium on in vitro callus induction and shoot organogenesis of tomato (Solanum lycopersicum L.)].

Science.gov (United States)

Khaliluev, M R; Bogoutdinova, L R; Baranova, G B; Baranova, E N; Kharchenko, P N; Dolgov, S V

2014-01-01

The influence of explant type as well as of the type of growth regulators and concentration on callus induction processes and somatic organogenesis of shoots was studied in vitro on four tomato genotypes of Russian breeding. Cytological study of callus tissue was conducted. It was established that tomato varieties possess a substantially greater ability to indirect shoot organogenesis compared with the F1 hybrid. The highest frequency of somatic organogenesis of shoots, as well as their number per explant, was observed for most of the genotypes studied during the cultivation of cotyledons on Murashige-Skoog culture medium containing 2 mg/l of zeatin in combination with 0.1 mg/l of 3-indoleacetic acid. An effective protocol of indirect somatic organogenesis of shoots from different explants of tomato varieties with a frequency of more than 80% was developed.

Effects of calcium gluconate and ascorbic acid on controlling shoot ...

African Journals Online (AJOL)

In vitro shoot necrosis is a quite widespread disorder affecting raspberry micropropagation. This study was conducted to investigate effects of calcium gluconate and ascorbic acid on shoot necrosis and dieback of raspberry shoots during micropropagation. Nodal segments of primocane-fruiting raspberry cultivars 'Allgold', ...

Tragedy and the Meaning of School Shootings

Science.gov (United States)

Warnick, Bryan R.; Johnson, Benjamin A.; Rocha, Samuel

2010-01-01

School shootings are traumatic events that cause a community to question itself, its values, and its educational systems. In this article Bryan Warnick, Benjamin Johnson, and Samuel Rocha explore the meanings of school shootings by examining three recent books on school violence. Topics that grow out of these books include (1) how school shootings…

Distributed trouble-shooting

NARCIS (Netherlands)

Post, W.M.; Bogaard, S.A.A. van den; Rasker, P.C.

2004-01-01

When knowledge, required for trouble-shooting at sea, can be supplied real-time but from a distance, problems, such as with the limited availability of specialists, and the high costs of maintenance, may be tackled. Unclear is, however, how this redistribution of knowledge will work in practice. We

Firearm Legislation and Fatal Police Shootings in the United States.

Science.gov (United States)

Kivisto, Aaron J; Ray, Bradley; Phalen, Peter L

2017-07-01

To examine whether stricter firearm legislation is associated with rates of fatal police shootings. We used a cross-sectional, state-level design to evaluate the effect of state-level firearm legislation on rates of fatal police shootings from January 1, 2015, through October 31, 2016. We measured state-level variation in firearm laws with legislative scorecards from the Brady Center, and for fatal police shootings we used The Counted, an online database maintained by The Guardian. State-level firearm legislation was significantly associated with lower rates of fatal police shootings (incidence rate ratio = 0.961; 95% confidence interval = 0.939, 0.984). When we controlled for sociodemographic factors, states in the top quartile of legislative strength had a 51% lower incidence rate than did states in the lowest quartile. Laws aimed at strengthening background checks, promoting safe storage, and reducing gun trafficking were associated with fewer fatal police shootings. Legislative restrictions on firearms are associated with reductions in fatal police shootings. Public Health Implications. Although further research is necessary to determine causality and potential mechanisms, firearm legislation is a potential policy solution for reducing fatal police shootings in the United States.

Primary chondrosarcoma of the trachea with extensive extraluminal growth.

Science.gov (United States)

Ryabov, Andrey; Pikin, Oleg; Sokolov, Victor; Volchenko, Nadezda

2017-09-01

Primary chondrosarcoma of the trachea is an extremely rare non-epithelial neoplasm with only few cases published in the literature. We present a rare case of tracheal chondrosarcoma with extensive extraluminal growth. We operated a patient with obstructive tumour of the upper third of the trachea via partial sternotomy. Before surgery, a Hanarostent was put into the trachea to treat a life-threatening stenosis. Postoperative period was uneventful. We discuss the incidence, clinical presentation and treatment options in patients with rare tracheal tumours. In some cases, a multidisciplinary approach (endoscopic intervention followed by surgical resection) is an effective treatment tool. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Device for Automated Cutting and Transfer of Plant Shoots

Science.gov (United States)

Cipra, Raymond; Das, Hari; Ali, Khaled; Hong, Dennis

2003-01-01

A device that enables the automated cutting and transfer of plant shoots is undergoing development for use in the propagation of plants in a nursery or laboratory. At present, it is standard practice for a human technician to use a knife and forceps to cut, separate, and grasp a plant shoot. The great advantage offered by the present device is that its design and operation are simpler than would be those of a device based on the manual cutting/separation/grasping procedure. [The present device should not be confused with a prior device developed for partly the same purpose and described in Compliant Gripper for a Robotic Manipulator (NPO-21104), NASA Tech Briefs, Vol. 27, No. 3 (March 2003), page 59.]. The device (see figure) includes a circular tube sharpened at its open (lower) end and mounted on a robotic manipulator at its closed (upper) end. The robotic manipulator simply pushes the sharpened open end of the tube down onto a bed of plants and rotates a few degrees clockwise then counterclockwise about the vertical axis, causing the tube to cut a cylindrical plug of plant material. Exploiting the natural friction between the tube and plug, the tube retains the plug, without need for a gripping mechanism and control. The robotic manipulator then retracts the tube, translates it to a new location over a plant-growth tray, and inserts the tube part way into the growth medium at this location in the tray. A short burst of compressed air is admitted to the upper end of the tube to eject the plug of plant material and drive it into the growth medium. A prototype has been tested and verified to function substantially as intended. It is projected that in the fully developed robotic plant-propagation system, the robot control system would include a machine- vision subsystem that would automatically guide the robotic manipulator in choosing the positions from which to cut plugs of plant material. Planned further development efforts also include more testing and

Effects of light on the growth and photosynthesis of Egeria najas planchon

Directory of Open Access Journals (Sweden)

Tavechio Washington Luiz Gomes

2003-01-01

Full Text Available Photosynthesis and growth of Egeria najas (Hydrocharitaceae from a subtropical reservoir (Itaipu Reservoir, Brazil-Paraguay were measured in response to low light intensities (0-124 µM m-2 s-1 PAR in the laboratory. Photosynthesis approached saturation in the range of light intensities used and light compensation point was reached at ca. 6-22 µM m-2 s-1 PAR, indicating that this species had a low light requirement for growth. Light stimulated shoot and root relative growth rates (RGR but it was not related to ratios between root:shoot RGR. Laboratory observations indicated that (i both shoot and root growth were simultaneously stimulated by light and (ii the low light requirements of E. najas may explain its incidence in the Itaipu Reservoir, where biogenic as well as abiogenic turbidity is high.

Sprout growth of some hardwoods following clearcutting in the Dapgok District of the Seoul National University Forests

Energy Technology Data Exchange (ETDEWEB)

Lee, D.K.; Kim, K.D.

1982-01-01

Stewartia koreana and Styrax japonica produced the best growth of coppice shoots and suckers, while Carpinus laxiflora produced none. Lindera erythrocarpa, Euonymus sachalinensis. Cornus controversa, Prunus sargentii and Fraxinus rhynchophylla showed good short growth after felling and good seedling emergence. Growth of shoots and suckers was better on fertile than on poor sites.

The Level of Vision Necessary for Competitive Performance in Rifle Shooting: Setting the Standards for Paralympic Shooting with Vision Impairment

NARCIS (Netherlands)

Allen, P.M.; Latham, K.; Mann, D.L.; Ravensbergen, H.J.C.; Myint, J.

2016-01-01

The aim of this study was to investigate the level of vision impairment (VI) that would reduce performance in shooting; to guide development of entry criteria to visually impaired (VI) shooting. Nineteen international-level shooters without VI took part in the study. Participants shot an air rifle,

The role of attachment in recovery after a school-shooting trauma

Directory of Open Access Journals (Sweden)

Tuija Turunen

2014-07-01

Full Text Available Background: Survivors of life-endangering trauma use varying resources that help them to recover. Attachment system activates in the times of distress, and is expected to associate with stress responses, arousal regulation, and mental health. Objective: We examined the associations of attachment style with posttraumatic stress disorders (PTSD symptoms and dissociative symptoms, and posttraumatic growth (PTG among students exposed to a school shooting in Finland in a three-wave follow-up setting. Method: Participants were students (M age=24.9 years; 95% female who were followed 4 (T1, N=236, 16 (T2, N=180, and 28 months (T3, N=137 after the shooting. The assessments included the Attachment Style Questionnaire, the Impact of Event Scale, part of the Adolescent Dissociative Experiences Scale and the Posttraumatic Growth Inventory. Results: Securely attached survivors had lower levels of posttraumatic stress and dissociative symptoms than preoccupied at T1 and T2 as hypothesized. At T3 survivors with avoidant attachment style had higher levels of intrusive and hyperarousal symptoms than those with secure style. Concerning PTG, survivors with avoidant attachment style scored lower in PTG at T3 than survivors with both secure and preoccupied style. Conclusion: Secure attachment style was beneficial in trauma recovery. A challenge to the health care systems is to acknowledge that survivors with preoccupied and avoidant attachment styles react uniquely to trauma, and thus need help in different doses, modalities, and timings.

Soil type affects Pinus ponderosa var. scopulorum (Pinaceae) seedling growth in simulated drought experiments.

Science.gov (United States)

Lindsey, Alexander J; Kilgore, Jason S

2013-08-01

Effects of drought stress and media type interactions on growth of Pinus ponderosa var. scopulorum germinants were investigated. • Soil properties and growth responses under drought were compared across four growth media types: two native soils (dolomitic limestone and granite), a soil-less industry standard conifer medium, and a custom-mixed conifer medium. After 35 d of growth, the seedlings under drought stress (reduced watering) produced less shoot and root biomass than watered control seedlings. Organic media led to decreased root biomass, but increased root length and shoot biomass relative to the mineral soils. • Media type affected root-to-shoot biomass partitioning of P. ponderosa var. scopulorum, which may influence net photosynthetic rates, growth, and long-term seedling survival. Further work should examine how specific soil properties like bulk density and organic matter influence biomass allocation in greenhouse studies.

Ferns: the missing link in shoot evolution and development

Directory of Open Access Journals (Sweden)

Andrew Robert George Plackett

2015-11-01

Full Text Available Shoot development in land plants is a remarkably complex process that gives rise to an extreme diversity of forms. Our current understanding of shoot developmental mechanisms comes almost entirely from studies of angiosperms (flowering plants, the most recently diverged plant lineage. Shoot development in angiosperms is based around a layered multicellular apical meristem that produces lateral organs and/or secondary meristems from populations of founder cells at its periphery. In contrast, non-seed plant shoots develop from either single apical initials or from a small population of morphologically distinct apical cells. Although developmental and molecular information is becoming available for non-flowering plants, such as the model moss Physcomitrella patens, making valid comparisons between highly divergent lineages is extremely challenging. As sister group to the seed plants, the monilophytes (ferns and relatives represent an excellent phylogenetic midpoint of comparison for unlocking the evolution of shoot developmental mechanisms, and recent technical advances have finally made transgenic analysis possible in the emerging model fern Ceratopteris richardii. This review compares and contrasts our current understanding of shoot development in different land plant lineages with the aim of highlighting the potential role that the fern C. richardii could play in shedding light on the evolution of underlying genetic regulatory mechanisms.

Effect of Plant Growth Regulators on a Shoot and Root Formation from the Leaf and Flower Culture of a Standard-type Chrysanthemum 'Jinba'

International Nuclear Information System (INIS)

Lee, J.S.; Lee, G.J.; Chung, S.J.; Kim, J.B.; Kim, D.S.; Kang, S.Y.

2008-01-01

In this study we investigated the conditions of a higher frequency for regenerated plants from different explants of a standard-type chrysanthemum 'Jinba'. In vitro culture was initiated on an MS medium containing 3% sucrose, 0.8% agar, and 5 μM benzyl adenine (BA) with naphthalene acetic acid (NAA) by using surface-sterilized leaf and flower tissues from greenhouse-grown plants. Direct shoot regeneration from the leaf and flower explants was obtained 21 to 28 days after the initial culture. Among the seven combinations of the growth regulators used for the culture, the most efficient condition for the shoot and root formation from the leaf tissue was obtained when the MS basic medium was supplemented with 0.5 mg L-¹ BA and 1.0 mg L-¹ NAA, and 0.1 mg L-¹ BA and 0.5 mg L-¹ NAA, while the culture using floret tissues was most efficient on the medium supplemented with 0.5 mg L-¹ BA and 0.5 mg L-¹ NAA, and 0.1 mg L-¹ BA and 1.0 mg L-¹ NAA. These results will provide valuable information to help set up an efficient system for a tissue culture of chrysanthemum cv. Jinba to improve one or some of its negative traits in combination with a radiation mutagenesis approach

"Warning: This image has been digitally altered": The effect of disclaimer labels added to fashion magazine shoots on women's body dissatisfaction.

Science.gov (United States)

Tiggemann, Marika; Brown, Zoe; Zaccardo, Mia; Thomas, Nicole

2017-06-01

The present experiment aimed to investigate the impact of the addition of disclaimer labels to fashion magazine shoots on women's body dissatisfaction. Participants were 320 female undergraduate students who viewed fashion shoots containing a thin and attractive model with no disclaimer label, or a small, large, or very large disclaimer label, or product images. Although thin-ideal fashion shoot images resulted in greater body dissatisfaction than product images, there was no significant effect of disclaimer label. Internalisation of the thin ideal was found to moderate the effect of disclaimer label, such that internalisation predicted increased body dissatisfaction in the no label and small label conditions, but not in the larger label conditions. Overall, the results showed no benefit for any size of disclaimer label in ameliorating the negative effect of viewing thin-ideal media images. It was concluded that more extensive research is required before the effective implementation of disclaimer labels. Copyright © 2017 Elsevier Ltd. All rights reserved.

In vitro propagation and production of cardiotonic glycosides in shoot cultures of Digitalis purpurea L. by elicitation and precursor feeding.

Science.gov (United States)

Patil, Jitendra Gopichand; Ahire, Mahendra Laxman; Nitnaware, Kirti Manik; Panda, Sayantan; Bhatt, Vijay P; Kishor, Polavarapu B Kavi; Nikam, Tukaram Dayaram

2013-03-01

Digitalis purpurea L. (Scrophulariaceae; Foxglove) is a source of cardiotonic glycosides such as digitoxin and digoxin which are commercially applied in the treatment to strengthen cardiac diffusion and to regulate heart rhythm. This investigation deals with in vitro propagation and elicited production of cardiotonic glycosides digitoxin and digoxin in shoot cultures of D. purpurea L. In vitro germinated seedlings were used as a primary source of explants. Multiple shoot formation was achieved for three explant types (nodal, internodal, and leaf) cultured on Murashige and Skoog (MS) medium with several treatments of cytokinins (6-benzyladenine-BA; kinetin-Kin; and thidiazuron-TDZ) and auxins (indole-3-acetic acid-IAA; α-naphthaleneacetic acid-NAA; and 2,4-dichlorophenoxy acetic acid-2,4-D). Maximum multiple shoots (12.7 ± 0.6) were produced from nodal explants on MS + 7.5 μM BA. Shoots were rooted in vitro on MS containing 15 μM IAA. Rooted plantlets were successfully acclimatized. To further maintain the multiple shoot induction, mother tissue was cut into four equal parts and repeatedly sub-cultured on fresh shoot induction liquid medium after each harvest. On adaptation of this strategy, an average of 18 shoots per explant could be produced. This strategy was applied for the production of biomass and glycosides digitoxin and digoxin in shoot cultures on MS medium supplemented with 7.5 μM BA and several treatments with plant growth regulators, incubation period, abiotic (salicylic acid, mannitol, sorbitol, PEG-6000, NaCl, and KCl), biotic (Aspergillus niger, Helminthosporium sp., Alternaria sp., chitin, and yeast extract) elicitors, and precursors (progesterone, cholesterol, and squalene). The treatment of KCl, mycelial mass of Helminthosporium sp., and progesterone were highly effective for the production of cardenolides. In the presence of progesterone (200 to 300 mg/l), digitoxin and digoxin accumulation was enhanced by 9.1- and 11.9-folds

Mental illness, mass shootings, and the politics of American firearms.

Science.gov (United States)

Metzl, Jonathan M; MacLeish, Kenneth T

2015-02-01

Four assumptions frequently arise in the aftermath of mass shootings in the United States: (1) that mental illness causes gun violence, (2) that psychiatric diagnosis can predict gun crime, (3) that shootings represent the deranged acts of mentally ill loners, and (4) that gun control "won't prevent" another Newtown (Connecticut school mass shooting). Each of these statements is certainly true in particular instances. Yet, as we show, notions of mental illness that emerge in relation to mass shootings frequently reflect larger cultural stereotypes and anxieties about matters such as race/ethnicity, social class, and politics. These issues become obscured when mass shootings come to stand in for all gun crime, and when "mentally ill" ceases to be a medical designation and becomes a sign of violent threat.

Studies on growth, yield and shoot and fruit borer (Leucinodes orbonalis Guenee.) resistance in M3 progenies of Solanum macrocarpon L

International Nuclear Information System (INIS)

Srinivasappa, K.N.; Ramanjini Gowda, P.H.; Thimmaiah, S.K.; Mahadevu, P.

1998-01-01

Shoot and fruit borer (Leucinodes orbonalis Guenee) is a serious pest in brinjal and no variety is found to be resistant to this dreaded pest. Solanum macrocarpon, a wild relative of brinjal is found to be resistant to shoot and fruit borer infestation. Attempts were made to hybridise between S. melongena and S. macrocarpon, but it was unsuccessful due to ovule abortion. The present study was undertaken to evaluate the promising mutants in M 3 generation for improved fruit quality besides its unbroken resistance and for further crop improvement

Multiple vantage points on the mental health effects of mass shootings.

Science.gov (United States)

Shultz, James M; Thoresen, Siri; Flynn, Brian W; Muschert, Glenn W; Shaw, Jon A; Espinel, Zelde; Walter, Frank G; Gaither, Joshua B; Garcia-Barcena, Yanira; O'Keefe, Kaitlin; Cohen, Alyssa M

2014-09-01

The phenomenon of mass shootings has emerged over the past 50 years. A high proportion of rampage shootings have occurred in the United States, and secondarily, in European nations with otherwise low firearm homicide rates; yet, paradoxically, shooting massacres are not prominent in the Latin American nations with the highest firearm homicide rates in the world. A review of the scientific literature from 2010 to early 2014 reveals that, at the individual level, mental health effects include psychological distress and clinically significant elevations in posttraumatic stress, depression, and anxiety symptoms in relation to the degree of physical exposure and social proximity to the shooting incident. Psychological repercussions extend to the surrounding affected community. In the aftermath of the deadliest mass shooting on record, Norway has been in the vanguard of intervention research focusing on rapid delivery of psychological support and services to survivors of the "Oslo Terror." Grounded on a detailed review of the clinical literature on the mental health effects of mass shootings, this paper also incorporates wide-ranging co-author expertise to delineate: 1) the patterning of mass shootings within the international context of firearm homicides, 2) the effects of shooting rampages on children and adolescents, 3) the psychological effects for wounded victims and the emergency healthcare personnel who care for them, 4) the disaster behavioral health considerations for preparedness and response, and 5) the media "framing" of mass shooting incidents in relation to the portrayal of mental health themes.

Effects of news media messages about mass shootings on attitudes toward persons with serious mental illness and public support for gun control policies.

Science.gov (United States)

McGinty, Emma E; Webster, Daniel W; Barry, Colleen L

2013-05-01

In recent years, mass shootings by persons with serious mental illness have received extensive news media coverage. The authors test the effects of news stories about mass shootings on public attitudes toward persons with serious mental illness and support for gun control policies. They also examine whether news coverage of proposals to prevent persons with serious mental illness from having guns exacerbates the public's negative attitudes toward this group. The authors conducted a survey-embedded randomized experiment using a national sample (N=1,797) from an online panel. Respondents were randomly assigned to groups instructed to read one of three news stories or to a no-exposure control group. The news stories described, respectively, a mass shooting by a person with serious mental illness, the same mass shooting and a proposal for gun restrictions for persons with serious mental illness, and the same mass shooting and a proposal to ban large-capacity magazines. Outcome measures included attitudes toward working with or living near a person with serious mental illness, perceived dangerousness of persons with serious mental illness, and support for gun restrictions for persons with serious mental illness and for a ban on large-capacity magazines. Compared with the control group, the story about a mass shooting heightened respondents' negative attitudes toward persons with serious mental illness and raised support for gun restrictions for this group and for a ban on large-capacity magazines. Including information about the gun restriction policy in a story about a mass shooting did not heighten negative attitudes toward persons with serious mental illness or raise support for the restrictions. The aftermath of mass shootings is often viewed as a window of opportunity to garner support for gun control policies, but it also exacerbates negative attitudes toward persons with serious mental illness.

In vitro mass propagation of Salvia canariensis by axillary shoots

Directory of Open Access Journals (Sweden)

Sebastiana Mederos Molina

2014-01-01

Full Text Available During the establishment of shoots of Salvia canariensis L., five environmental factor treatments were applied. For each axillary node two shoots grew well when explants were incubated at continued ligth for 15 days followed by 16 hrs photoperiod by 30 days. Shoots multiplication was improved on a modified Murashige and Skoog (MS (1962 medium - MS + 825 mg/l NH4NO3 - supplemented with 10-7 M BA and 10-7 M NAA. The shoots produced well developed root systems within three weeks after transfer to the same culture medium supplemented with 5x 10-7 M NAA.

UV-B Radiation Impacts Shoot Tissue Pigment Composition in Allium fistulosum L. Cultigens

Directory of Open Access Journals (Sweden)

Kristin R. Abney

2013-01-01

Full Text Available Plants from the Allium genus are valued worldwide for culinary flavor and medicinal attributes. In this study, 16 cultigens of bunching onion (Allium fistulosum L. were grown in a glasshouse under filtered UV radiation (control or supplemental UV-B radiation [7.0 μmol·m−2·s−2 (2.68 W·m−2] to determine impacts on growth, physiological parameters, and nutritional quality. Supplemental UV-B radiation influenced shoot tissue carotenoid concentrations in some, but not all, of the bunching onions. Xanthophyll carotenoid pigments lutein and β-carotene and chlorophylls a and b in shoot tissues differed between UV-B radiation treatments and among cultigens. Cultigen “Pesoenyj” responded to supplemental UV-B radiation with increases in the ratio of zeaxanthin + antheraxanthin to zeaxanthin + antheraxanthin + violaxanthin, which may indicate a flux in the xanthophyll carotenoids towards deepoxydation, commonly found under high irradiance stress. Increases in carotenoid concentrations would be expected to increase crop nutritional values.

Morphological Evaluation of Shoots Regenerated from Hygromycin-Resistant Rice Callus (cv IACuba-28

Directory of Open Access Journals (Sweden)

Maylin Pérez Bernal

2007-01-01

Full Text Available An evaluation system based on the morphological characteristics of regenerated hygromycin-resistant rice callus shoots was established for correlating such characteristics with shoot viability on hygromycin. Embryogenic rice calli were transformed by Agrobacterium tumefaciens (EHA105/ pCAMBIA1300, containing the hygromycin-phosphotransferase gene as selection marker. After two weeks on selection medium, hygromycin-resistant calli were transferred to regeneration medium. Regenerated shoots were extracted every 5 days (over a 30-day period and classified into three classes according to their morphological structure: class I: vigorous shoot having typical bipolar structure; class II: shoot having small root compared to apical length, or shoot without roots; class III: shoots having an abnormal appearance, such as malformed leaves or albinism. Individualised shoots were transferred to MS medium containing hygromycin for evaluating their resistance to antibiotics. A relationship was observed between regenerated shoots’ morphological characteristics and the percentage of shoots’ viability on hygromycin. Class I prevailed at early shoot extraction and was the most resistant to hygromycin. Drastic class I reduction was found with later shoot extraction, whilst classes II and III became increased. Likewise, shoot viability became radically reduced on MS medium containing hygromycin. This result might be applied for improving efficiency regarding obtaining transgenic rice plants, taking into account the best time for obtaining high percentages of hygromycin-resistant shoots having the best morphological characteristics.

Shoot Differentiation in Callus Cultures of Datura Innoxia

DEFF Research Database (Denmark)

Engvild, Kjeld Christensen

1973-01-01

promoted shoot differentiation. Gibberellic acid inhibited shoot formation weakly, but inhibited proper leaf blade formation. Root differentiation was rare. The callus cultures of Datura innoxia grew rapidly (100-fold in 4 weeks) on a slightly modified Murashige and Skoog medium (0.5 mg/l thiamin · HCl, p...

Soil Type Affects Pinus ponderosa var. scopulorum (Pinaceae Seedling Growth in Simulated Drought Experiments

Directory of Open Access Journals (Sweden)

Alexander J. Lindsey

2013-07-01

Full Text Available Premise of the study: Effects of drought stress and media type interactions on growth of Pinus ponderosa var. scopulorum germinants were investigated. Methods and Results: Soil properties and growth responses under drought were compared across four growth media types: two native soils (dolomitic limestone and granite, a soil-less industry standard conifer medium, and a custom-mixed conifer medium. After 35 d of growth, the seedlings under drought stress (reduced watering produced less shoot and root biomass than watered control seedlings. Organic media led to decreased root biomass, but increased root length and shoot biomass relative to the mineral soils. Conclusions: Media type affected root-to-shoot biomass partitioning of P. ponderosa var. scopulorum, which may influence net photosynthetic rates, growth, and long-term seedling survival. Further work should examine how specific soil properties like bulk density and organic matter influence biomass allocation in greenhouse studies.

Handgun Acquisitions in California After Two Mass Shootings.

Science.gov (United States)

Studdert, David M; Zhang, Yifan; Rodden, Jonathan A; Hyndman, Rob J; Wintemute, Garen J

2017-05-16

Mass shootings are common in the United States. They are the most visible form of firearm violence. Their effect on personal decisions to purchase firearms is not well-understood. To determine changes in handgun acquisition patterns after the mass shootings in Newtown, Connecticut, in 2012 and San Bernardino, California, in 2015. Time-series analysis using seasonal autoregressive integrated moving-average (SARIMA) models. California. Adults who acquired handguns between 2007 and 2016. Excess handgun acquisitions (defined as the difference between actual and expected acquisitions) in the 6-week and 12-week periods after each shooting, overall and within subgroups of acquirers. In the 6 weeks after the Newtown and San Bernardino shootings, there were 25 705 (95% prediction interval, 17 411 to 32 788) and 27 413 (prediction interval, 15 188 to 37 734) excess acquisitions, respectively, representing increases of 53% (95% CI, 30% to 80%) and 41% (CI, 19% to 68%) over expected volume. Large increases in acquisitions occurred among white and Hispanic persons, but not among black persons, and among persons with no record of having previously acquired a handgun. After the San Bernardino shootings, acquisition rates increased by 85% among residents of that city and adjacent neighborhoods, compared with 35% elsewhere in California. The data relate to handguns in 1 state. The statistical analysis cannot establish causality. Large increases in handgun acquisitions occurred after these 2 mass shootings. The spikes were short-lived and accounted for less than 10% of annual handgun acquisitions statewide. Further research should examine whether repeated shocks of this kind lead to substantial increases in the prevalence of firearm ownership. None.

Measures to inhibit the growth of apple tree top with the `gala´ variety

Directory of Open Access Journals (Sweden)

Matjaž BEBER

2015-11-01

Full Text Available In Fruit Research Center Maribor different methods of less vigorous growth of apple tree top with the variety `Gala´ were conducted during the period from 2010 to 2013: applying a coating of the central leader at a height of 2.2 m with 2 % solution of growth regulator NAA (Luxan Late – Val and plant resin, the use of the growth retardant Regalis (2 times, of replacing the the top of the tree with the highest appropriate bent branch, removal of new shoots 28 days after flowering (tearing and the June cut after the completion of the primary growth. Increment of annual shoots and harvest in the top (over 2.2 m was followed. Most commonly used practices, the June cut and tearing of young shoots resulted in the strongest growth in the top. The vigour of the top of the tree was the best reduced by the use of plant growth regulators (Regalis and NAA top coating and replacing the top of the tree. The highest yield of the top of the tree was achieved by using Regalis, meanwhile tearing of the young shoots gave the lowest yield. The replacing the top of the tree is suitable measure for organic production, because it successfully reduces the vigour of the tree top without the use of growth regulators.

Impact of lead tolerant plant growth promoting rhizobacteria on growth, physiology, antioxidant activities, yield and lead content in sunflower in lead contaminated soil.

Science.gov (United States)

Saleem, Muhammad; Asghar, Hafiz Naeem; Zahir, Zahir Ahmad; Shahid, Muhammad

2018-03-01

Present study was conducted to evaluate the effect of lead tolerant plant growth promoting rhizobacteria (LTPGPR) on growth, physiology, yield, antioxidant activities and lead uptake in sunflower in soil contaminated with lead under pot conditions. Three pre-characterized LTPGP strains (S2 (Pseudomonas gessardii strain BLP141), S5 (Pseudomonas fluorescens A506) and S10 (Pseudomonas fluorescens strain LMG 2189)) were used to inoculate sunflower growing in soil contaminated with different levels (300, 600 and 900 mg kg -1 ) of lead by using lead nitrate salt as source of lead. Treatments were arranged according to completely randomized design with factorial arrangements. At harvesting, data regarding growth attributes (root shoot length, root shoot fresh and dry weights), yield per plant, physiological attributes (Chlorophyll 'a', 'b' and carotenoids content), antioxidant activities (Ascorbate peroxidase, catalase, superoxide dismutase and glutathione reductase), proline and malanodialdehyde content, and lead content in root, shoot and achenes of sunflower were recorded. Data were analysed by standard statistical procedures. Results showed that lead contamination reduced the plants growth, physiology and yield at all levels of lead stress. But application of LTPGPR in soil contaminated with lead improved plant growth, physiology, yield, and antioxidant activities, proline, and reduced the malanodialdehyde content (that is reduced by the application of different strains in lead contamination) of sunflower as compared to plants grown in soil without inoculation. Inoculation also promoted the uptake of lead in root, shoots and reduced the uptake of lead in achenes of plants as compared to plants in lead contamination without inoculation. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Effect of High School Shootings on Schools and Student Performance

OpenAIRE

Louis-Philippe Beland; Dongwoo Kim

2015-01-01

We analyze how fatal shootings in high schools affect schools and students using data from shooting databases, school report cards, and the Common Core of Data. We examine schools’ test scores, enrollment, and number of teachers, as well as graduation, attendance, and suspension rates at schools that experienced a shooting, employing a difference-in-differences strategy that uses other high schools in the same district as the comparison group. Our findings suggest that homicidal shootings s...

Effects of high CO2 on growth and metabolism of Arabidopsis seedlings during growth with a constantly limited supply of nitrogen.

Science.gov (United States)

Takatani, Nobuyuki; Ito, Takuro; Kiba, Takatoshi; Mori, Marie; Miyamoto, Tetsuro; Maeda, Shin-Ichi; Omata, Tatsuo

2014-02-01

Elevated CO2 has been reported to stimulate plant growth under nitrogen-sufficient conditions, but the effects of CO2 on growth in a constantly nitrogen-limited state, which is relevant to most natural habitats of plants, remain unclear. Here, we maintained Arabidopsis seedlings under such conditions by growing a mutant with reduced nitrate uptake activity on a medium containing nitrate as the sole nitrogen source. Under nitrogen-sufficient conditions (i.e. in the presence of ammonium), growth of shoots and roots of both the wild type (WT) and the mutant was increased approximately 2-fold by elevated CO2. Growth stimulation of shoots and roots by elevated CO2 was observed in the WT growing with nitrate as the sole nitrogen source, but in the mutant grown with nitrate, the high-CO2 conditions stimulated only the growth of roots. In the mutant, elevated CO2 caused well-known symptoms of nitrogen-starved plants, including decreased shoot/root ratio, reduced nitrate content and accumulation of anthocyanin, but also had an increased Chl content in the shoot, which was contradictory to the known effect of nitrogen depletion. A high-CO2-responsive change specific to the mutant was not observed in the levels of the major metabolites, although CO2 responses were observed in the WT and the mutant. These results indicated that elevated CO2 causes nitrogen limitation in the seedlings grown with a constantly limited supply of nitrogen, but the Chl content and the root biomass of the plant increase to enhance the activities of both photosynthesis and nitrogen uptake, while maintaining normal metabolism and response to high CO2.

Methodology of shooting training using modern IT techniques

Science.gov (United States)

Gudzbeler, Grzegorz; Struniawski, Jarosław

2017-08-01

Mastering, improvement, shaping and preservation of skills of safe, efficient and effective use of the firearm requires the use of relevant methodology of conducting the shooting training. However reality of police trainings does not usually allow for intensive training shooting with the use of ammunition. An alternative solution is the use of modern training technologies. Example of this is the "Virtual system of improvement tactics of intervention services responsible for security and shooting training." Introduction of stimulator to police trainings will enable complete stuff preparation to achieve its tasks, creating potential of knowledge and experience in many areas, far exceeding the capabilities of conventional training.

Tall or short? Slender or thick? A plant strategy for regulating elongation growth of roots by low concentrations of gibberellin.

Science.gov (United States)

Tanimoto, Eiichi

2012-07-01

Since the plant hormone gibberellin (GA) was discovered as a fungal toxin that caused abnormal elongation of rice shoots, the physiological function of GA has mainly been investigated in relation to the regulation of plant height. However, an indispensable role for GA in root growth has been elucidated by using severely GA-depleted plants, either with a gene mutation in GA biosynthesis or which have been treated by an inhibitor of GA biosynthesis. The molecular sequence of GA signalling has also been studied to understand GA functions in root growth. This review addresses research progress on the physiological functions of GA in root growth. Concentration-dependent stimulation of elongation growth by GA is important for the regulation of plant height and root length. Thus the endogenous level of GA and/or the GA sensitivity of shoots and roots plays a role in determining the shoot-to-root ratio of the plant body. Since the shoot-to-root ratio is an important parameter for agricultural production, control of GA production and GA sensitivity may provide a strategy for improving agricultural productivity. The sequence of GA signal transduction has recently been unveiled, and some component molecules are suggested as candidate in planta regulatory sites and as points for the artificial manipulation of GA-mediated growth control. This paper reviews: (1) the breakthrough dose-response experiments that show that root growth is regulated by GA in a lower concentration range than is required for shoot growth; (2) research on the regulation of GA biosynthesis pathways that are known predominantly to control shoot growth; and (3) recent research on GA signalling pathways, including GA receptors, which have been suggested to participate in GA-mediated growth regulation. This provides useful information to suggest a possible strategy for the selective control of shoot and root growth, and to explain how GA plays a role in rosette and liana plants with tall or short, and slender

[Genetic regulation of plant shoot stem cells].

Science.gov (United States)

Al'bert, E V; Ezhova, T A

2013-02-01

This article describes the main features of plant stem cells and summarizes the results of studies of the genetic control of stem cell maintenance in the apical meristem of the shoot. It is demonstrated that the WUS-CLV gene system plays a key role in the maintenance of shoot apical stem cells and the formation of adventitious buds and somatic embryos. Unconventional concepts of plant stem cells are considered.

THE PRELIMINARY STUDIES ON THE INFLUENCE OF SHOOTING RANGES ON ENVIRONMENT

Directory of Open Access Journals (Sweden)

Karolina Wodnik

2017-08-01

Full Text Available The aim of the study was to assess the impact of the shooting activity on the environment. The studies were conducted in the area of the sports shooting range. The invertebrates assemblages were identified to the family level as well as morphospecies. The second method do not require the proficiency in identification. The following indices of the biodiversity were used for the assessment of the impact of sports shooting ranges: Simpson, Shannon-Wiener, Margalef, Berger-Parker and Menhinick. A decreased biodiversity was observed at two studied sites comparing to the reference site what proves the influence of shooting activity on the biodiversity and suggest disturbance of the ecosystem integrity because of shooting activity.

Influence of growth retardant on growth and development of Euphorbia pulcherrima Willd. ex Klotzsch

Directory of Open Access Journals (Sweden)

Anna Pobudkiewicz

2014-09-01

Full Text Available This study was undertaken to evaluate the influence of single foliar flurprimidol treatment on morphology and transpiration of ‘Roman’ and ‘Freedom Red’ poinsettias. The growth retardant flurprimidol (Topflor 015 SL was applied once as a foliar spray at concentrations of 5, 10 or 15 mg × dm-3 when lateral shoots were about 5 cm in length. Single foliar flurprimidol treatment was sufficient to inhibit stem elongation of both poinsettia cultivars. The degree of growth inhibition depended on cultivar and growth retardant concentration. As compared to the control, the shoots of flurprimidol treated ‘Roman’ and ‘Freedom Red’ plants were up to 44% and 37% shorter, respectively. The desirable plant heights for ‘Roman’ and ‘Freedom Red’ poinsettias were obtained with flurprimidol at concentrations of 5 and 10 mg × dm-3, respectively. The shoots of flurprimidol sprayed poinsettia were also more rigid and aligned relative to each other and thus the bracts on the plant were placed on the same level. The diameters of growth retardant treated poinsettias were up to 13% narrower. The leaf areas, petiole lengths, fresh and dry weights of ‘Roman’ and ‘Freedom Red’ poinsettias treated with flurprimidol were substantially smaller as compared to the control. The bract diameters of both poinsettia cultivars were only slightly affected by growth retardant application. Plants exposed to flurprimidol had also intensified green leaf pigmentation. There was almost no abscission of the oldest leaves in the low portions of growth retardant treated plants, compared to those of the control ones. Flurprimidol had no effect on transpiration rate per unit leaf area and stomatal conductance in both poinsettia cultivars. No phytotoxicity was observed in flurprimidol treated plants. Chemical name used: α-(1-methylethyl-α-[4-(trifluromethoxyphenyl]-5-pyrimidinemethanol (flurprimidol.

Tolerance to high soil temperature in foxtail millet (Setaria italica L.) is related to shoot and root growth and metabolism.

Science.gov (United States)

Aidoo, Moses Kwame; Bdolach, Eyal; Fait, Aaron; Lazarovitch, Naftali; Rachmilevitch, Shimon

2016-09-01

Roots play important roles in regulating whole-plant carbon and water relations in response to extreme soil temperature. Three foxtail millet (Setaria italica L.) lines (448-Ames 21521, 463-P1391643 and 523-P1219619) were subjected to two different soil temperatures (28 and 38 °C). The gas exchange, chlorophyll fluorescence, root morphology and central metabolism of leaves and roots were studied at the grain-filling stage. High soil temperature (38 °C) significantly influenced the shoot transpiration, stomatal conductance, photosynthesis, root growth and metabolism of all lines. The root length and area were significantly reduced in lines 448 and 463 in response to the stress, while only a small non-specific reduction was observed in line 523 in response to the treatment. The shift of root metabolites in response to high soil temperature was also genotype specific. In response to high soil temperature, glutamate, proline and pyroglutamate were reduced in line 448, and alanine, aspartate, glycine, pyroglutamate, serine, threonine and valine were accumulated in line 463. In the roots of line 523, serine, threonine, valine, isomaltose, maltose, raffinose, malate and itaconate were accumulated. Root tolerance to high soil temperature was evident in line 523, in its roots growth potential, lower photosynthesis and stomatal conductance rates, and effective utilization and assimilation of membrane carbon and nitrogen, coupled with the accumulation of protective metabolites. Copyright © 2016. Published by Elsevier Masson SAS.

Induction and inhibition of film yeast from fermented bamboo shoot by seasoning plants

Directory of Open Access Journals (Sweden)

Jaruwan Maneesri

2007-07-01

Full Text Available Three samples of fermented bamboo shoot taken from a village in Amphur Kokpho, Pattani Province, were microbiologically examined. Total viable count was between at 104-105 cfu/ml while pH range was between 3.4-4.4. Isolation and identification of film yeast on surface of fermented liquid revealed Saccharomyces cerevisiae J1, Candida krusei J2 and Candida krusei J3. When film yeast was cultivated in liquid culture with different NaCl concentrations (0, 2.5, 5 and 7.5% (w/v, all species tolerated 2.5% NaCl addition. However, growth decreased depending on NaCl concentration. S. cerevisiae J1 grew faster than C. krusei J2 and C. krusei J3. The cultivation of film yeast in medium with different agar concentrations (0.3, 0.5, 1 and 1.5% (w/v within 24 h showed that 0.3% was the optimal agar concentration. Seasoning plants (garlic, ginger, galangal, lemon grass, lesser galangal, clove, kaffir lime, garcinia and shallot were extracted with water (3% (w/v and tested for growth inhibition. Results showed the clove extract inhibited all yeast strains within 12 h and after that the efficiency of inhibition was decreased. At low concentration of 0.75% (w/v clove extract could inhibit film yeast in fermented bamboo shoot.

Influence of Aphelenchus avenae on Vesicular-arbuscular Endomycorrhizal Growth Response in Cotton.

Science.gov (United States)

Hussey, R S; Roncadori, R W

1981-01-01

The influence of Aphelenchus avenae on the relationship between cotton (Gossypium hirsutum 'Stoneville 213') and Gigaspora margarita or Glomus etunicatus was assessed by its effect on the mycorrhizal stimulation of plant growth and microorganism reproduction. The mycophagous nematode usually did not suppress stimulation of shoot growth resulting from mycorrhizae (G. margarita) at inoculum levels of 3,000 or 6,000 nematodes per pot, but retarded root growth at 6,000 per pot. When the nematode inoculum was increased to 10, 40, or 80 thousand, G. margarita stimulation of shoot or root growth was retarded at the two higher rates. Shoot growth enhancement by G. etunicatus was suppressed by 10 thousand A. avenae but not by 40 or 80 thousand. A. avenae reproduced better when the nematode was added 3 wk after G. margarita than with simultaneous inoculations. Sporulation of both fungi was affected little by the mycophagous nematode. The high numbers of A. avenae required for an antagonistic effect probably precludes the occurrence of any significant interaction between these two organisms under field conditions.

Cytokinin-producing, plant growth-promoting rhizobacteria that confer resistance to drought stress in Platycladus orientalis container seedlings.

Science.gov (United States)

Liu, Fangchun; Xing, Shangjun; Ma, Hailin; Du, Zhenyu; Ma, Bingyao

2013-10-01

One of the proposed mechanisms through which plant growth-promoting rhizobacteria (PGPR) enhance plant growth is the production of plant growth regulators, especially cytokinin. However, little information is available regarding cytokinin-producing PGPR inoculation on growth and water stress consistence of forest container seedlings under drought condition. This study determined the effects of Bacillus subtilis on hormone concentration, drought resistance, and plant growth under water-stressed conditions. Although no significant difference was observed under well-watered conditions, leaves of inoculated Platycladus orientalis (oriental thuja) seedlings under drought stress had higher relative water content and leaf water potential compared with those of noninoculated ones. Regardless of water supply levels, the root exudates, namely sugars, amino acids and organic acids, significantly increased because of B. subtilis inoculation. Water stress reduced shoot cytokinins by 39.14 %. However, inoculation decreased this deficit to only 10.22 %. The elevated levels of cytokinins in P. orientalis shoot were associated with higher concentration of abscisic acid (ABA). Stomatal conductance was significantly increased by B. subtilis inoculation in well-watered seedlings. However, the promoting effect of cytokinins on stomatal conductance was hampered, possibly by the combined action of elevated cytokinins and ABA. B. subtilis inoculation increased the shoot dry weight of well-watered and drought seedlings by 34.85 and 19.23 %, as well as the root by 15.445 and 13.99 %, respectively. Consequently, the root/shoot ratio significantly decreased, indicative of the greater benefits of PGPR on shoot growth than root. Thus, inoculation of cytokinin-producing PGPR in container seedlings can alleviate the drought stress and interfere with the suppression of shoot growth, showing a real potential to perform as a drought stress inhibitor in arid environments.

Comparative proteomics reveals the physiological differences between winter tender shoots and spring tender shoots of a novel tea (Camellia sinensis L.) cultivar evergrowing in winter.

Science.gov (United States)

Liu, Shengjie; Gao, Jiadong; Chen, Zhongjian; Qiao, Xiaoyan; Huang, Hualin; Cui, Baiyuan; Zhu, Qingfeng; Dai, Zhangyan; Wu, Hualing; Pan, Yayan; Yang, Chengwei; Liu, Jun

2017-11-20

A recently discovered tea [Camellia sinensis (L.) O. Kuntze] cultivar can generate tender shoots in winter. We performed comparative proteomics to analyze the differentially accumulated proteins between winter and spring tender shoots of this clonal cultivar to reveal the physiological basis of its evergrowing character during winter. We extracted proteins from the winter and spring tender shoots (newly formed two leaves and a bud) of the evergrowing tea cultivar "Dongcha11" respectively. Thirty-three differentially accumulated high-confidence proteins were identified by matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF / TOF MS). Among these, 24 proteins had increased abundance while nine showed were decreased abundance in winter tender shoots as compared with the spring tender shoots. We categorized the differentially accumulated proteins into eight critical biological processes based on protein function annotation including photosynthesis, cell structure, protein synthesis & destination, transporters, metabolism of sugars and polysaccharides, secondary metabolism, disease/defense and proteins with unknown functions. Proteins with increased abundance in winter tender shoots were mainly related to the processes of photosynthesis, cytoskeleton and protein synthesis, whereas those with decreased abundance were correlated to metabolism and the secondary metabolism of polyphenolic flavonoids. Biochemical analysis showed that the total contents of soluble sugar and amino acid were higher in winter tender shoots while tea polyphenols were lower as compared with spring tender shoots. Our study suggested that the simultaneous increase in the abundance of photosynthesis-related proteins rubisco, plastocyanin, and ATP synthase delta chain, metabolism-related proteins eIF4 and protease subunits, and the cytoskeleton-structure associated proteins phosphatidylinositol transfer protein and profilin may be because of the adaptation of the

Soil type affects Pinus ponderosa var. scopulorum (Pinaceae) seedling growth in simulated drought experiments1

Science.gov (United States)

Lindsey, Alexander J.; Kilgore, Jason S.

2013-01-01

• Premise of the study: Effects of drought stress and media type interactions on growth of Pinus ponderosa var. scopulorum germinants were investigated. • Methods and Results: Soil properties and growth responses under drought were compared across four growth media types: two native soils (dolomitic limestone and granite), a soil-less industry standard conifer medium, and a custom-mixed conifer medium. After 35 d of growth, the seedlings under drought stress (reduced watering) produced less shoot and root biomass than watered control seedlings. Organic media led to decreased root biomass, but increased root length and shoot biomass relative to the mineral soils. • Conclusions: Media type affected root-to-shoot biomass partitioning of P. ponderosa var. scopulorum, which may influence net photosynthetic rates, growth, and long-term seedling survival. Further work should examine how specific soil properties like bulk density and organic matter influence biomass allocation in greenhouse studies. PMID:25202578

Bringing sexy back: reclaiming the body aesthetic via self-shooting

DEFF Research Database (Denmark)

Tiidenberg, Katrin

2014-01-01

’s ‘technologies of the self’ to analyze self-shooting (taking photos of one-self). Constricting societal norms of sexuality, body shape and body practices influence how my participants (N=20, 10 female, 9 male, 1 transgender, ages 21 - 51, average age 34) live their embodied and sexual lives. Through self-shooting...... and by negotiating the community specific issues of control, power and the gaze, they are able to construct a new, empowered, embodied identity for themselves. I look at self-shooting and selfie-blogging as a practice of reclaiming control over one’s embodied self AND over the body-aesthetic, thus appropriating what...... is and is not ‘sexy’. The NSFW self-shooting community offers a safe space otherwise so hard to find within the body/sexuality-normative mainstream culture. This makes self-shooting a collective therapeutic activity. In their self-images participants construct themselves as ‘beautiful’, ‘sexy’, ‘devious’, ‘more than...

The Effect of High School Shootings on Schools and Student Performance

Science.gov (United States)

Beland, Louis-Philippe; Kim, Dongwoo

2016-01-01

We analyze how fatal shootings in high schools affect schools and students using data from shooting databases, school report cards, and the Common Core of Data. We examine schools' test scores, enrollment, number of teachers, graduation, attendance, and suspension rates at schools that experienced a shooting, employing a difference-in-differences…

In vitro shoot multiplication of Ziziphus spina-christi by shoot tip culture

African Journals Online (AJOL)

USER

2010-02-08

Feb 8, 2010 ... Key words: Clonal propagation, cidir, shoot tip culture, Ziziphus spina-christi (L.) Desf. INTRODUCTION. Ziziphus spina-christi (L.) Desf., locally known as cidir, is a multipurpose tree species belonging to the botanical family Rhamnaceae. It is an important cultivated tree and one of the few truly native tree ...

[Effect of extensively hydrolyzed formula on growth and development of infants with very/extremely low birth weight].

Science.gov (United States)

Gu, Chun-Yan; Jiang, Hui-Fen; Wang, Jin-Xiu

2017-08-01

To study the effect of extensively hydrolyzed formula on the growth and development in very low birth weight (VLBW) and extremely low birth weight (ELBW) infants. A total of 375 VLBW or ELBW infants were enrolled and divided into an observation group (187 infants) and a control group (188 infants) using a random number table. The infants in the observation group were given extensively hydrolyzed formula, and when the amount of extensively hydrolyzed formula reached 10 mL/time, it was changed to the standard formula for preterm infants. The infants in the control group were given standard formula for preterm infants. Both groups were fed for 4 consecutive weeks and were compared in terms of incidence rate of feeding intolerance, time to establish full enteral feeding, time to complete meconium excretion, number of spontaneous bowel movements, growth and development, motilin level at 4 and 10 days after feeding, and incidence rate of infection. Compared with the control group, the observation group had a lower rate of feeding intolerance (Pdevelopment, and reduce the incidence of infection in VLBW and ELBW infants.

Dynamic allocation and transfer of non-structural carbohydrates, a possible mechanism for the explosive growth of Moso bamboo (Phyllostachys heterocycla)

Science.gov (United States)

Song, Xinzhang; Peng, Changhui; Zhou, Guomo; Gu, Honghao; Li, Quan; Zhang, Chao

2016-01-01

Moso bamboo can rapidly complete its growth in both height and diameter within only 35–40 days after shoot emergence. However, the underlying mechanism for this “explosive growth” remains poorly understood. We investigated the dynamics of non-structural carbohydrates (NSCs) in shoots and attached mature bamboos over a 20-month period. The results showed that Moso bamboos rapidly completed their height and diameter growth within 38 days. At the same time, attached mature bamboos transferred almost all the NSCs of their leaves, branches, and especially trunks and rhizomes to the “explosively growing” shoots via underground rhizomes for the structural growth and metabolism of shoots. Approximately 4 months after shoot emergence, this transfer stopped when the leaves of the young bamboos could independently provide enough photoassimilates to meet the carbon demands of the young bamboos. During this period, the NSC content of the leaves, branches, trunks and rhizomes of mature bamboos declined by 1.5, 23, 28 and 5 fold, respectively. The trunk contributed the most NSCs to the shoots. Our findings provide new insight and a possible rational mechanism explaining the “explosive growth” of Moso bamboo and shed new light on understanding the role of NSCs in the rapid growth of Moso bamboo. PMID:27181522

Ship and Shoot

Science.gov (United States)

Woods, Ron

2012-01-01

Ron Woods shared incredibly valuable insights gained during his 28 years at the Kennedy Space Center (KSC) packaging Flight Crew Equipment for shuttle and ISS missions. In particular, Woods shared anecdotes and photos from various processing events. The moral of these stories and the main focus of this discussion were the additional processing efforts and effects related to a "ship-and-shoot" philosophy toward flight hardware.

The impact of agricultural extension and roads on poverty and consumption growth in fifteen Ethiopian villages

NARCIS (Netherlands)

Dercon, S.; Gilligan, D.O.; Hoddinott, J.; Woldehanna, T.

2009-01-01

This article investigates whether public investments that led to improvements in road quality and increased access to agricultural extension services led to faster consumption growth and lower rates of poverty in rural Ethiopia. Estimating an Instrumental Variables model using Generalized Methods of

Highly efficient in vitro adventitious shoot regeneration of Adenosma ...

African Journals Online (AJOL)

Adenosma glutinosum (Linn.) Druce is an important aromatic plant, but no information is available regarding its regeneration, callus induction and proliferation from leaf explants. In this study, an in vitro shoot regeneration procedure was developed for native A. glutinosum using leaf explants. Callus induction and shoots ...

Expression of the Arabidopsis vacuolar H+-pyrophosphatase gene (AVP1) improves the shoot biomass of transgenic barley and increases grain yield in a saline field

KAUST Repository

Schilling, Rhiannon K.

2013-11-22

Cereal varieties with improved salinity tolerance are needed to achieve profitable grain yields in saline soils. The expression of AVP1, an Arabidopsis gene encoding a vacuolar proton pumping pyrophosphatase (H+-PPase), has been shown to improve the salinity tolerance of transgenic plants in greenhouse conditions. However, the potential for this gene to improve the grain yield of cereal crops in a saline field has yet to be evaluated. Recent advances in high-throughput nondestructive phenotyping technologies also offer an opportunity to quantitatively evaluate the growth of transgenic plants under abiotic stress through time. In this study, the growth of transgenic barley expressing AVP1 was evaluated under saline conditions in a pot experiment using nondestructive plant imaging and in a saline field trial. Greenhouse-grown transgenic barley expressing AVP1 produced a larger shoot biomass compared to segregants, as determined by an increase in projected shoot area, when grown in soil with 150 mm NaCl. This increase in shoot biomass of transgenic AVP1 barley occurred from an early growth stage and also in nonsaline conditions. In a saline field, the transgenic barley expressing AVP1 also showed an increase in shoot biomass and, importantly, produced a greater grain yield per plant compared to wild-type plants. Interestingly, the expression of AVP1 did not alter barley leaf sodium concentrations in either greenhouse- or field-grown plants. This study validates our greenhouse-based experiments and indicates that transgenic barley expressing AVP1 is a promising option for increasing cereal crop productivity in saline fields. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Expression of the Arabidopsis vacuolar H+-pyrophosphatase gene (AVP1) improves the shoot biomass of transgenic barley and increases grain yield in a saline field

KAUST Repository

Schilling, Rhiannon K.; Marschner, Petra; Shavrukov, Yuri N.; Berger, Bettina; Tester, Mark A.; Roy, Stuart John; Plett, Darren Craig

2013-01-01

Cereal varieties with improved salinity tolerance are needed to achieve profitable grain yields in saline soils. The expression of AVP1, an Arabidopsis gene encoding a vacuolar proton pumping pyrophosphatase (H+-PPase), has been shown to improve the salinity tolerance of transgenic plants in greenhouse conditions. However, the potential for this gene to improve the grain yield of cereal crops in a saline field has yet to be evaluated. Recent advances in high-throughput nondestructive phenotyping technologies also offer an opportunity to quantitatively evaluate the growth of transgenic plants under abiotic stress through time. In this study, the growth of transgenic barley expressing AVP1 was evaluated under saline conditions in a pot experiment using nondestructive plant imaging and in a saline field trial. Greenhouse-grown transgenic barley expressing AVP1 produced a larger shoot biomass compared to segregants, as determined by an increase in projected shoot area, when grown in soil with 150 mm NaCl. This increase in shoot biomass of transgenic AVP1 barley occurred from an early growth stage and also in nonsaline conditions. In a saline field, the transgenic barley expressing AVP1 also showed an increase in shoot biomass and, importantly, produced a greater grain yield per plant compared to wild-type plants. Interestingly, the expression of AVP1 did not alter barley leaf sodium concentrations in either greenhouse- or field-grown plants. This study validates our greenhouse-based experiments and indicates that transgenic barley expressing AVP1 is a promising option for increasing cereal crop productivity in saline fields. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Crescimento da parte aérea de cana crua e queimada Shoot growth of green and burned canes

Directory of Open Access Journals (Sweden)

Ivan André Alvarez

1999-01-01

Full Text Available Este trabalho teve como objetivos: 1. comparar o crescimento de cana colhida crua, mecanizada e de cana após a queima, colhida manualmente; 2. avaliar a influência do clima sobre as duas condições de crescimento e 3. analisar o comportamento do crescimento de cana crua e cana queimada nos 1º e 2º anos de rebrota, através de curvas adaptadas. A pesquisa foi realizada no município de Morro Agudo, SP, de julho de 1995 a julho de 1997. A variedade cultivada foi a SP 70 -1143. Utilizaram-se como indicadores de crescimento os seguintes índices biométricos: número de perfilhos, número de folhas, matéria seca de colmos e de folhas, IAF e avaliou-se a influência das temperaturas e das umidades do ar, do solo e das folhas. Adotou-se regressão polinomial e regressão não-linear para se adaptar os dados às curvas de crescimento. O crescimento no primeiro ciclo foi semelhante para cana crua e cana queimada. No início do segundo ciclo ocorreu maior crescimento em cana crua, enquanto que no final, foi maior em cana queimada. O perfilhamento da cana crua não apresentou diferenças significativas que confirmem a influência negativa da palha na rebrota. Os fatores climatológicos, isoladamente, não provocaram mudanças nos ciclos de crescimento de maneira que se identificasse uma tendência geral. As diferenças expressas na curva de crescimento do 1º para o 2º ano são devidas aos fatores climatológicos, tanto para cana crua como para cana queimada.This work had as objectives: 1. to compare the shoot growth between green cane, mechanically harvested and burned cane, harvested manually; 2. to evaluate the influence of the weather on the two conditions of growth and 3. to analyze the growth of green cane and cane burned in the 1st and 2nd years of second ratoon cane crop, by means of adapted curves. The research was performed in Morro Agudo, SP, Brazil from July 1995 to July 1997. The cultivar was the SP 70 -1143. As growth indicators the

Structuring agreements for seismic group shoots

International Nuclear Information System (INIS)

Keeping, C.E.

1999-01-01

Sigma Explorations Inc. sells licenses to use Sigma owned seismic data. The company participates with exploration and production companies in the joint acquisition of semi-private participation surveys. This paper discusses three major types of seismic group shoots and the essential elements of the agreements that govern or should govern them. They are: (1) exploration and production company joint ventures, (2) publicly offered spec shoots, and (3) semi-private participation surveys. The key issue with the exploration and production company joint ventures is that the companies are owners of the seismic data in proportion to their contribution towards the cost of the program. Their use of the data should be restricted to those situations permitted by the other owners. These are not often well documented, and there is much concern in the industry as a result. The key issue with publicly offered spec shoots is that the seismic company ultimately owns the data and the client exploration and production company is a licensee and must behave as such. In most such cases the rights and responsibilities are well documented in formal agreements that are signed in advance of the program's beginning date

Effect of Hormones on Direct Shoot Regeneration in Hypocotyl Explants of Tomato

Directory of Open Access Journals (Sweden)

Rizwan RASHID

2010-03-01

Full Text Available This study was conducted for developing a high frequency regeneration system in two genotypes of tomato (Lycopersicon esculentum Mill., �Punjab Upma� and �IPA-3� for direct shoot regeneration from hypocotyl explants. The explants were excised from in vitro tomato seedlings and cultured on MS medium supplemented with different concentrations and combinations of hormones. Direct regeneration was significantly influenced by the genotype hormones combination and concentrations. The MS medium supplemented with (Kinetin 0.5 mg/l and (BAP 0.5 mg/l was found optimum for inducing direct shoot regeneration and number of shoots per explant from hypocotyl explants on this medium. Shoot regeneration per cent in �Punjab Upma� and �IPA-3� per cent was recorded to be highest i.e (86.02 and (82.57 respectively. Besides this, average number shoots per explant was also highest i.e (3.16 in case of �Punjab Upma� and (2.93 in case of �IPA-3�. A significant decline was observed in percent shoot regeneration and average number of shoots per explant with increase in the hormonal concentration. Shoots were obtained and transferred to the elongation medium (MS + BAP 0.3 mg/l. Hundred per cent rooting was induced in separated shoots upon culturing on MS and � MS basal media. Hardening on moist cotton showed maximum plantlet survival rate in case of both genotypes. After hardening, plants were transferred to soil. Thus, a tissue culture base line was established in tomato for obtaining direct regeneration using hypocotyl as explants.

Effect of Hormones on Direct Shoot Regeneration in Hypocotyl Explants of Tomato

Directory of Open Access Journals (Sweden)

Rizwan RASHID

2010-03-01

Full Text Available This study was conducted for developing a high frequency regeneration system in two genotypes of tomato (Lycopersicon esculentum Mill., Punjab Upma and IPA-3 for direct shoot regeneration from hypocotyl explants. The explants were excised from in vitro tomato seedlings and cultured on MS medium supplemented with different concentrations and combinations of hormones. Direct regeneration was significantly influenced by the genotype hormones combination and concentrations. The MS medium supplemented with (Kinetin 0.5 mg/l and (BAP 0.5 mg/l was found optimum for inducing direct shoot regeneration and number of shoots per explant from hypocotyl explants on this medium. Shoot regeneration per cent in Punjab Upma and IPA-3 per cent was recorded to be highest i.e (86.02 and (82.57 respectively. Besides this, average number shoots per explant was also highest i.e (3.16 in case of Punjab Upma and (2.93 in case of IPA-3. A significant decline was observed in percent shoot regeneration and average number of shoots per explant with increase in the hormonal concentration. Shoots were obtained and transferred to the elongation medium (MS + BAP 0.3 mg/l. Hundred per cent rooting was induced in separated shoots upon culturing on MS and MS basal media. Hardening on moist cotton showed maximum plantlet survival rate in case of both genotypes. After hardening, plants were transferred to soil. Thus, a tissue culture base line was established in tomato for obtaining direct regeneration using hypocotyl as explants.

Effect of antioxidants and associate changes in antioxidant enzymes in controlling browning and necrosis of proliferating shoots of elite Jatropha curcas L

International Nuclear Information System (INIS)

Misra, Pratibha; Toppo, Dibya D.; Gupta, Neha; Chakrabarty, Debasis; Tuli, Rakesh

2010-01-01

A high yielding elite plant of Jatropha curcas was established under aseptic condition from field-grown nodal explants. Shoots were proliferated in MS medium supplemented with 0.5 mg dm -3 benzyladenine and 0.1 mg dm -3 indolebutyric acid along with 10 mg dm -3 adenine sulphate and a combination of 15 mg dm -3 each of L-glutamine and L-arginine. However, within 15-20 d of culture incubation, tissue browning/necrosis leading to poor plant regeneration in vitro was observed. A set of different antioxidants, namely, reduced glutathione, ascorbic acid, tocopherol and cysteine were used in the medium individually and in combination to solve the problem of tissue browning and necrosis. The addition of antioxidants proved beneficial for the growth of the shoots. The optimum medium comprised of 25 mg dm -3 reduced glutathione and 10 mg dm -3 ascorbic acid, where proliferating shoots having highest leaf canopy area, remained fresh, green and regenerative up to 40 d of culture incubation without any subculture. The activities of antioxidant enzymes, such as superoxide dismutase was higher in control shoots, indicating that tissue browning/necrosis was associated with oxidative stress which was further supported by higher contents of H 2 O 2 and phenolics in control shoots compared to the other treatments. Similarly glutathione reductase, ascorbate peroxidase and guiacol peroxidase was higher in treated shoots than control indicating that these shoots have developed antioxidant enzymatic protective system which determine the ability to survive in oxidative stress and up regulation of these enzymes would help to reduce the built up of reactive oxygen species.

Hospital-based shootings in the United States: 2000 to 2011.

Science.gov (United States)

Kelen, Gabor D; Catlett, Christina L; Kubit, Joshua G; Hsieh, Yu-Hsiang

2012-12-01

Workplace violence in health care settings is a frequent occurrence. Emergency departments (EDs) are considered particularly vulnerable. Gunfire in hospitals is of particular concern; however, information about such workplace violence is limited. Therefore, we characterize US hospital-based shootings from 2000 to 2011. Using LexisNexis, Google, Netscape, PubMed, and ScienceDirect, we searched reports for acute care hospital shooting events in the United States for 2000 through 2011. All hospital-based shootings with at least 1 injured victim were analyzed. Of 9,360 search "hits," 154 hospital-related shootings were identified, 91 (59%) inside the hospital and 63 (41%) outside on hospital grounds. Shootings occurred in 40 states, with 235 injured or dead victims. Perpetrators were overwhelmingly men (91%) but represented all adult age groups. The ED environs were the most common site (29%), followed by the parking lot (23%) and patient rooms (19%). Most events involved a determined shooter with a strong motive as defined by grudge (27%), suicide (21%), "euthanizing" an ill relative (14%), and prisoner escape (11%). Ambient society violence (9%) and mentally unstable patients (4%) were comparatively infrequent. The most common victim was the perpetrator (45%). Hospital employees composed 20% of victims; physician (3%) and nurse (5%) victims were relatively infrequent. Event characteristics that distinguished the ED from other sites included younger perpetrator, more likely in custody, and unlikely to have a personal relationship with the victim (ill relative, grudge, coworker). In 23% of shootings within the ED, the weapon was a security officer's gun taken by the perpetrator. Case fatality inside the hospital was much lower in the ED setting (19%) than other sites (73%). Although it is likely that not every hospital-based shooting was identified, such events are relatively rare compared with other forms of workplace violence. The unpredictable nature of this type of

Model Persamaan Massa Karbon Akar Pohon dan Root-Shoot Ratio Massa Karbon (Equation Models of Tree Root Carbon Mass and Root-Shoot Carbon Mass Ratio

Directory of Open Access Journals (Sweden)

Elias .

2011-03-01

Full Text Available The case study was conducted in the area of Acacia mangium plantation at BKPH Parung Panjang, KPH Bogor. The objective of the study was to formulate equation models of tree root carbon mass and root to shoot carbon mass ratio of the plantation. It was found that carbon content in the parts of tree biomass (stems, branches, twigs, leaves, and roots was different, in which the highest and the lowest carbon content was in the main stem of the tree and in the leaves, respectively. The main stem and leaves of tree accounted for 70% of tree biomass. The root-shoot ratio of root biomass to tree biomass above the ground and the root-shoot ratio of root biomass to main stem biomass was 0.1443 and 0.25771, respectively, in which 75% of tree carbon mass was in the main stem and roots of tree. It was also found that the root-shoot ratio of root carbon mass to tree carbon mass above the ground and the root-shoot ratio of root carbon mass to tree main stem carbon mass was 0.1442 and 0.2034, respectively. All allometric equation models of tree root carbon mass of A. mangium have a high goodness-of-fit as indicated by its high adjusted R2.Keywords: Acacia mangium, allometric, root-shoot ratio, biomass, carbon mass

Mass shootings: a meta-analysis of the dose-response relationship.

Science.gov (United States)

Wilson, Laura C

2014-12-01

A meta-analysis was conducted to examine the dose-response theory as it relates to posttraumatic stress symptoms (PTSSs) following mass shootings. It was hypothesized that greater exposure to a mass shooting would be associated with greater PTSSs. Trauma exposure in the current study was broadly defined as the extent to which a person experienced or learned about a mass shooting. The meta-analysis identified 11 qualifying studies that included 13 independent effect sizes from a total of 8,047 participants. The overall weighted mean effect size, based on a random effects model, was r = .19, p shooting on the relationship between exposure and PTSSs. Because so few studies satisfied the inclusion criteria, the present study also documents that this area of the literature is underresearched. Copyright © 2014 International Society for Traumatic Stress Studies.

Youth Responses to School Shootings: A Reviw

DEFF Research Database (Denmark)

Travers, Áine

2018-01-01

PURPOSE OF REVIEW:This paper aims to synthesize research relating to youth responses to school shootings between 2014 and 2017. The main questions it addresses are how such events impact young people psychologically, and what risk or protective factors may contribute to different trajectories...... of recovery? RECENT FINDINGS:Recent research suggests that most young people exposed to school shootings demonstrate resilience, exhibiting no long-term dysfunction. However, a minority will experience severe and chronic symptoms. The likelihood of experiencing clinically significant reactions is influenced...

Effect of shading intensity on morphological and color traits, and chemical components of new tea (Camellia sinensis L.) shoots under direct covering cultivation.

Science.gov (United States)

Sano, Tomohito; Horie, Hideki; Matsunaga, Akiko; Hirono, Yuhei

2018-05-02

Use of covering cultivation to shade tea (Camellia sinensis L.) trees to produce high-quality, high-priced green tea has recently increased in Japan. Knowledge of shading effects on morphological and color traits, and chemical components of new tea shoots is important for product quality and productivity. We assessed these traits of tea shoots and their relationships under covering cultivation of various radiation intensities. Leaf thickness, LMA (leaf mass per area), and leaf density of new tea leaves were smaller under covering culture than under open-field culture. SPAD values and chlorophyll contents were larger under covering culture than under open culture. The derived exponential equation for estimating chlorophyll contents from SPAD values was improved by considering leaf thickness. Covering culture decreased EC (epicatechin) and EGC (epigallocatechin) contents, and increased theanine and caffeine contents. Principal component analysis on shoot and leaf traits indicated that LMA, and chlorophyll, EC, and EGC contents were strongly associated with shading effects. Morphological and color traits, and chemical components of new tea shoots and leaves varied depending on radiation intensity, shoot growth, and cropping season. These findings are useful for covering cultivation with high quality and high productivity in tea gardens. This article is protected by copyright. All rights reserved.

Efficient regeneration of plants from shoot tip explants of ...

African Journals Online (AJOL)

Dendrobium densiflorum Lindl. is one of the horticulturally important orchids of Nepal due to its beautiful yellowish flower and medicinal properties. The present study was carried out for plant regeneration from shoot tip explants of D. densiflorum by tissue culture technique. The shoot tip explants of this species, obtained ...

Response of Syngonium podophyllum L. ‘White Butterfly’ shoot cultures to alternative media additives and gelling agents, and flow cytometric analysis of regenerants

Directory of Open Access Journals (Sweden)

JAIME A. TEIXEIRA DA SILVA

2015-05-01

Full Text Available Abstract. Teixeira da Silva JA. 2015. Response of Syngonium podophyllum L. ‘White Butterfly’ shoot cultures to alternative media additives and gelling agents, and flow cytometric analysis of regenerants. Nusantara Bioscience 7: 26-32. Syngonium podophyllum L. (arrowhead vine is a popular leafy indoor pot plant whose tissue culture has been established, primarily through in vitro shoot culture, but several interesting aspects have not yet been explored. In this study, cv. ‘White Butterfly’ was used to investigate the response of shoot formation to alternative gelling agents and media additives. Gellan gum (Gelrite® at 2 g/L resulted in greater leaf production, plantlet fresh weight and higher chlorophyll content (SPAD value than all other gelling agents tested, including agar, Bacto agar, phytagel, oatmeal agar, potato dextrose agar, barley starch and corn starch, when on a basal Hyponex® (NPK = 6.5: 6: 19; 3 g/L medium. Several alternative liquid medium additives tested (low and full fat milk, Coca-Cola®, coffee, Japanese green, Oolong and Darjeeling teas negatively impacted plant growth, stunted roots and decreased chlorophyll content (SPAD value of leaves. Plant growth on medium with refined sucrose or table sugar responded similarly. Poor growth was observed when crude extract from a high rebaudioside-containing stevia (Stevia rebaudiana Bertoni line - an artificial sweetener - was used. Leaf tissue from the control did not show any endopolyploidy but low levels of endopolyploidy (8C were detected in some treatments.

Manipulation of hemoglobin expression affects Arabidopsis shoot organogenesis

DEFF Research Database (Denmark)

Wang, Yaping; Elhiti, Mohamed; Hebelstrup, Kim

2011-01-01

Over the past few years non-symbiotic plant hemoglobins have been described in a variety of plant species where they fulfill several functions ranging from detoxification processes to basic aspects of plant growth and post-embryonic development. To date no information is available on the role...... of hemoglobins during invitro morphogenesis. Shoot organogenesis was induced in Arabidopsis lines constitutively expressing class 1, 2 and 3 hemoglobins (GLB1, 2 and 3) and lines in which the respective genes were either downregulated by RNAi (GLB1) or knocked out (GLB2 and GLB3). The process was executed......, 15, and 16), feed-back repressors of the cytokinin pathway, was repressed in both hemoglobin over-expressors whereas that of several Type-B ARRs (ARR2, 12, and 13), transcription activators of cytokinin-responsive genes, was induced. Such changes enhanced the sensitivity of the root explants...

A hybrid model for mapping relative differences in belowground biomass and root: Shoot ratios using spectral reflectance, foliar N and plant biophysical data within coastal marsh

Science.gov (United States)

Jessica L. O'Connell,; Byrd, Kristin B.; Maggi Kelly,

2015-01-01

Broad-scale estimates of belowground biomass are needed to understand wetland resiliency and C and N cycling, but these estimates are difficult to obtain because root:shoot ratios vary considerably both within and between species. We used remotely-sensed estimates of two aboveground plant characteristics, aboveground biomass and % foliar N to explore biomass allocation in low diversity freshwater impounded peatlands (Sacramento-San Joaquin River Delta, CA, USA). We developed a hybrid modeling approach to relate remotely-sensed estimates of % foliar N (a surrogate for environmental N and plant available nutrients) and aboveground biomass to field-measured belowground biomass for species specific and mixed species models. We estimated up to 90% of variation in foliar N concentration using partial least squares (PLS) regression of full-spectrum field spectrometer reflectance data. Landsat 7 reflectance data explained up to 70% of % foliar N and 67% of aboveground biomass. Spectrally estimated foliar N or aboveground biomass had negative relationships with belowground biomass and root:shoot ratio in both Schoenoplectus acutus and Typha, consistent with a balanced growth model, which suggests plants only allocate growth belowground when additional nutrients are necessary to support shoot development. Hybrid models explained up to 76% of variation in belowground biomass and 86% of variation in root:shoot ratio. Our modeling approach provides a method for developing maps of spatial variation in wetland belowground biomass.

Unifying model of shoot gravitropism reveals proprioception as a central feature of posture control in plants

DEFF Research Database (Denmark)

Bastien, Renaud; Bohr, Tomas; Moulia, Bruno

2012-01-01

Gravitropism, the slow reorientation of plant growth in response to gravity, is a key determinant of the form and posture of land plants. Shoot gravitropism is triggered when statocysts sense the local angle of the growing organ relative to the gravitational field. Lateral transport of the hormone...... is thus as important as gravisensing in gravitropic control, and the B ratio can be measured as phenotype in genetic studies....

Metabolomic homeostasis shifts after callus formation and shoot regeneration in tomato

Science.gov (United States)

Kumari, Alka; Ray, Kamalika; Sadhna, Sadhna; Pandey, Arun Kumar; Sreelakshmi, Yellamaraju; Sharma, Rameshwar

2017-01-01

Plants can regenerate from a variety of tissues on culturing in appropriate media. However, the metabolic shifts involved in callus formation and shoot regeneration are largely unknown. The metabolic profiles of callus generated from tomato (Solanum lycopersicum) cotyledons and that of shoot regenerated from callus were compared with the pct1-2 mutant that exhibits enhanced polar auxin transport and the shr mutant that exhibits elevated nitric oxide levels. The transformation from cotyledon to callus involved a major shift in metabolite profiles with denser metabolic networks in the callus. In contrast, the transformation from callus to shoot involved minor changes in the networks. The metabolic networks in pct1-2 and shr mutants were distinct from wild type and were rewired with shifts in endogenous hormones and metabolite interactions. The callus formation was accompanied by a reduction in the levels of metabolites involved in cell wall lignification and cellular immunity. On the contrary, the levels of monoamines were upregulated in the callus and regenerated shoot. The callus formation and shoot regeneration were accompanied by an increase in salicylic acid in wild type and mutants. The transformation to the callus and also to the shoot downregulated LST8 and upregulated TOR transcript levels indicating a putative linkage between metabolic shift and TOR signalling pathway. The network analysis indicates that shift in metabolite profiles during callus formation and shoot regeneration is governed by a complex interaction between metabolites and endogenous hormones. PMID:28481937

An Analysis of US School Shooting Data (1840-2015)

Science.gov (United States)

Paradice, David

2017-01-01

This paper describes the construction and descriptive analysis of a data set of United States school shooting events. Three hundred forty-three shooting events are included, spanning 175 years of United States educational history. All levels of US educational institution are included. Events are included when a firearm is discharged, regardless of…

Revisiting the Virginia Tech Shootings: An Ecological Systems Analysis

Science.gov (United States)

Hong, Jun Sung; Cho, Hyunkag; Lee, Alvin Shiulain

2010-01-01

School shooting cases since the late 1990s have prompted school officials and legislators to develop and implement programs and measures that would prevent violence in school. Despite the number of explanations by the media, politicians, organizations, and researchers about the etiology of school shootings, we are not united in our understanding…

The effect of time constraints and running phases on combined event pistol shooting performance.

Science.gov (United States)

Dadswell, Clare; Payton, Carl; Holmes, Paul; Burden, Adrian

2016-01-01

The combined event is a crucial aspect of the modern pentathlon competition, but little is known about how shooting performance changes through the event. This study aimed to identify (i) how performance-related variables changed within each shooting series and (ii) how performance-related variables changed between each shooting series. Seventeen modern pentathletes completed combined event trials. An optoelectronic shooting system recorded score and pistol movement, and force platforms recorded centre of pressure movement 1 s prior to every shot. Heart rate and blood lactate values were recorded throughout the event. Whilst heart rate and blood lactate significantly increased between series (P  0.05). Thus, combined event shooting performance following each running phase appears similar to shooting performance following only 20 m of running. This finding has potential implications for the way in which modern pentathletes train for combined event shooting, and highlights the need for modern pentathletes to establish new methods with which to enhance shooting accuracy.

Efficient regeneration of sorghum, Sorghum bicolor (L.) Moench, from shoot-tip explant.

Science.gov (United States)

Syamala, D; Devi, Prathibha

2003-12-01

Novel protocols for production of multiple shoot-tip clumps and somatic embryos of Sorghum bicolor (L.) Moench were developed with long-term goal of crop improvement through genetic transformation. Multiple shoot-tip clumps were developed in vitro from shoot-tip explant of one-week old seedling, cultured on MS medium containing only BA (0.5, 1 or 2 mg/l) or both BA (1 or 2 mg/l) and 2,4-D (0.5 mg/l) with bi-weekly subculture. Somatic embryos were directly produced on the enlarged dome shaped growing structures that developed from the shoot-tips of one-week old seedling explants (without any callus formation) when cultured on MS medium supplemented with both 2,4-D (0.5 mg/l) and BA (0.5 mg/l). However, the supplementation of MS medium with only 2,4-D (0.5 mg/l) induced compact callus without any plantlet regeneration. Each multiple shoot-clump was capable of regenerating more than 80 shoots via an intensive differentiation of both axillary and adventitious shoot buds, the somatic embryos were capable of 90% germination, plant conversion and regeneration. The regenerated shoots could be efficiently rooted on MS medium containing indole-3-butyric acid (IBA 1 mg/l). The plants were successfully transplanted to glasshouse and grown to maturity with a survival rate of 98%. Morphogenetic response of the explants was found to be genotypically independent.

A digital photography and analysis system for estimation of root and shoot development in rice weed suppression studies in the field

Science.gov (United States)

Rice germplasm with an inherent ability to suppress weeds can potentially improve the economics and sustainability of weed control in rice. We devised a simple, rapid, and inexpensive digital imaging system to quantify several shoot and root growth characteristics in field-grown rice plants that ha...

Effects of different fertilizers on growth and nutrient uptake of Lolium multiflorum grown in Cd-contaminated soils.

Science.gov (United States)

Liu, Mohan; Li, Yang; Che, Yeye; Deng, Shaojun; Xiao, Yan

2017-10-01

This study aimed to explore the effects of different fertilizers and their combinations on growth and nutrient and Cd uptake of Lolium multiflorum. Compared with control treatment, chemical fertilizer, organic manure, and their conjunctions with biofertilizer increased shoot biomass. Biofertilizers were found to cause significant reductions in shoot biomass of plants grown in organic manure-treated and control soil. Decreased soil-available N and P and shoot N and K concentrations in biofertilizer amendment treatments indicated that plant growth and nutrient absorption might be negatively affected under nutrient deficiency conditions. Elevated shoot biomasses contributed to the highest shoot Cd contents in chemical fertilizer and chemical fertilizer + biofertilizer treatments among all treatments. But the maximum translocation efficiency occurred in biofertilizer + chemical fertilizer + organic manure treatment, followed by organic manure and chemical fertilizer + organic manure treatments. Based on the results, we can conclude that the application of only the biofertilizer Bacillus subtilis should be avoided in nutrient-limited soils. Chemical fertilizer application could benefit the amount of Cd in shoots, and organic manure application and its combinations could result in the higher translocation efficiency.

GPU based numerical simulation of core shooting process

Directory of Open Access Journals (Sweden)

Yi-zhong Zhang

2017-11-01

Full Text Available Core shooting process is the most widely used technique to make sand cores and it plays an important role in the quality of sand cores. Although numerical simulation can hopefully optimize the core shooting process, research on numerical simulation of the core shooting process is very limited. Based on a two-fluid model (TFM and a kinetic-friction constitutive correlation, a program for 3D numerical simulation of the core shooting process has been developed and achieved good agreements with in-situ experiments. To match the needs of engineering applications, a graphics processing unit (GPU has also been used to improve the calculation efficiency. The parallel algorithm based on the Compute Unified Device Architecture (CUDA platform can significantly decrease computing time by multi-threaded GPU. In this work, the program accelerated by CUDA parallelization method was developed and the accuracy of the calculations was ensured by comparing with in-situ experimental results photographed by a high-speed camera. The design and optimization of the parallel algorithm were discussed. The simulation result of a sand core test-piece indicated the improvement of the calculation efficiency by GPU. The developed program has also been validated by in-situ experiments with a transparent core-box, a high-speed camera, and a pressure measuring system. The computing time of the parallel program was reduced by nearly 95% while the simulation result was still quite consistent with experimental data. The GPU parallelization method can successfully solve the problem of low computational efficiency of the 3D sand shooting simulation program, and thus the developed GPU program is appropriate for engineering applications.

Micropropagation of Plantago asiatica L. through culture of shoot-tips

Directory of Open Access Journals (Sweden)

Joanna Makowczyńska

2011-01-01

Full Text Available Shoot-tip multiplication of the medicinal species - Plantago asiatica was carried on MS medium with IAA and BAP or kinetin. Best results in micropropagation were achieved by adding 0.1 mg/dm3 IAA and 1 mg/dm3 BAP. After 6 weeks shoots were transferred to MS medium for rooting. The resulting plantlets were transferred after 8 weeks into pots and after a period of adaptation into the ground (field culture. The species Plantago asiatica was propagated in vitro by shoot-tip multiplication for the first time.

The effects of increased phosphorus application on shoot dry matter ...

African Journals Online (AJOL)

The effects of increased phosphorus application on shoot dry matter, shoot P and Zn concentrations in wheat ( Triticum durum L.) and maize ( Zea mays L.)wheat ( Triticum durum L.) and maize ( Zea mays L.) grown in a calcareous soil.

Chemical Growth Regulators for Guayule Plants

Science.gov (United States)

Dastoor, M. N.; Schubert, W. W.; Petersen, G. R.

1982-01-01

Test Tubes containing Guayule - tissue cultures were used in experiments to test effects of chemical-growth regulators. The shoots grew in response to addition of 2-(3,4-dichlorophenoxy)-triethylamine (triethylamine (TEA) derivative) to agar medium. Preliminary results indicate that a class of compounds that promotes growth in soil may also promote growth in a culture medium. Further experiments are needed to define the effect of the TEA derivative.

The impact of brand extension fit, extension strategy and product exposure on attitudinal responses to brand extensions

OpenAIRE

Farstad, Lena Kvelland; Jabran, Mohammed

2013-01-01

Brand extensions have for decades been one of the most used strategies for growth, but the sad reality is that 8 out of 10 extensions fail, making the likelihood of failure unattractively high. In addition, competition and pressure on margins increases as retailers’ power improves due to proliferation of private labels. As a result, managers are eager for new innovative strategies that can differentiate their extension and improve likelihood of success. The purpose of this paper is therefore ...

How to talk (and not to talk) about school shootings

OpenAIRE

Scheper-Hughes, N

2018-01-01

© RAI 2018 In this guest editorial, the author addresses the latest school shootings at the Marjory Stoneman Douglas High School in Parkland, Florida. This event is weighed up against reports written by prominent academics, including anthropologists, during previous school shootings.

School Shootings Stun Reservation

Science.gov (United States)

Borja, Rhea R.; Cavanagh, Sean

2005-01-01

This article deals with the impact brought by the school shootings at Red Lake Indian Reservation in Minnesota to the school community. A deeply troubled 16-year-old student shot and killed seven other people and himself at a high school. The nation's deadliest school attack since the 1999 slayings at Colorado's suburban Columbine High School took…

Morphological and phenological shoot plasticity in a Mediterranean evergreen oak facing long-term increased drought.

Science.gov (United States)

Limousin, Jean-Marc; Rambal, Serge; Ourcival, Jean-Marc; Rodríguez-Calcerrada, Jesus; Pérez-Ramos, Ignacio M; Rodríguez-Cortina, Raquel; Misson, Laurent; Joffre, Richard

2012-06-01

Mediterranean trees must adjust their canopy leaf area to the unpredictable timing and severity of summer drought. The impact of increased drought on the canopy dynamics of the evergreen Quercus ilex was studied by measuring shoot growth, leaf production, litterfall, leafing phenology and leaf demography in a mature forest stand submitted to partial throughfall exclusion for 7 years. The leaf area index rapidly declined in the throughfall-exclusion plot and was 19% lower than in the control plot after 7 years of treatment. Consequently, leaf litterfall was significantly lower in the dry treatment. Such a decline in leaf area occurred through a change in branch allometry with a decreased number of ramifications produced and a reduction of the leaf area supported per unit sapwood area of the shoot (LA/SA). The leafing phenology was slightly delayed and the median leaf life span was slightly longer in the dry treatment. The canopy dynamics in both treatments were driven by water availability with a 1-year lag: leaf shedding and production were reduced following dry years; in contrast, leaf turnover was increased following wet years. The drought-induced decrease in leaf area, resulting from both plasticity in shoot development and slower leaf turnover, appeared to be a hydraulic adjustment to limit canopy transpiration and maintain leaf-specific hydraulic conductivity under drier conditions.

Skeletal development in Acropora palmata (Lamarck 1816): a scanning electron microscope (SEM) comparison demonstrating similar mechanisms of skeletal extension in axial versus encrusting growth

Science.gov (United States)

Gladfelter, E. H.

2007-12-01

Many Acropora palmata colonies consist of an encrusting basal portion and erect branches. Linear growth of the skeleton results in extension along the substrate (encrusting growth), lengthening of branches (axial growth) and thickening of branches and crust (radial growth). Scanning Electron Microscopy is used to compare the mechanisms of skeletal extension between encrusting growth and axial growth. In encrusting growth, the distal margin of the skeleton lacks corallites (which develop about 1 mm from the edge); in contrast, in axial growth, axial corallites along the branch tip form the distal portion of the skeleton. In both locations, the distal margin of the skeleton consists of a lattice-like structure composed of rods that extend from the body of the skeleton and bars that connect these rods. An actively extending skeleton is characterized by sharply pointed rods and partially developed bars. Distal growth of rods (and formation of bars) is effected by the formation of new sclerodermites. Each sclerodermite begins with the deposition of fusiform crystals (that range in length from 1 to 5 μm). These provide a surface for nucleation and growth of spherulitic tufts, clusters of short (<1 μm long) aragonite needles. The needles that are oriented perpendicular to the axis of the skeletal element (rod or bar), and perpendicular to the overlying calicoblastic epithelium, continue extension to appear on the surface of the skeleton as 10-15 μm wide bundles (of needle tips) called fasciculi. However, some crusts that abut competitors for space have a different morphology of skeletal elements (rods and bars). The distal edge of these crusts terminates in blunt coalescing rods, and bars that are fully formed. Absence of fusiform crystals, lack of sharply pointed rods and bars, and full development of sclerodermites characterize a skeletal region that has ceased, perhaps only temporarily, skeletal extension.

Violent mass shootings in Sweden from 1960 to 1995: profiles, patterns, and motives.

Science.gov (United States)

Lindquist, O; Lidberg, L

1998-03-01

During the past few decades, violent mass shooting in Sweden has increased rapidly. In the 36 years between 1960 and 1995, fourteen such occasions were recorded, during which 32 people were killed and 57 were wounded. The 14 offenders were men between the ages of 17 and 61 years. In the 20 years from 1960 to 1979, five shootings were committed by five offenders, leaving 10 dead and 13 wounded; in the 16 years between 1980 and 1995, there were nine different shootings committed by nine offenders, with 22 dead and 44 wounded. Seven of the shootings were classified as mass shootings, six as spree shootings, and one as a serial shooting. In all but four of these cases, the firearms used were illegal weapons. The four legal firearms belonged to an unemployed young laborer, an officer, a former United Nations (U.N.) soldier, and a member of the Swedish military volunteer corps. Of those killed, 68.8% were strangers to the offender; among the wounded, the corresponding figure was 89.5%. Profiles of the offenders and of the victims were studied. The psychiatric diagnoses among the offenders and the measures taken to prevent the increase in mass shooting in Sweden are presented.

Effects of wood biochar addition on growth of cherry radish (Raphanus sativus L. var. radculus pers)

Science.gov (United States)

Ke, Huadan; Zhang, Qian; Liu, Guocheng

2018-03-01

Extensive cultivation and unreasonable management of the farmland result in severe soil degradation such as compaction, acidification, and salinization. Our results showed that the biochar amendment increased the cherry radish germination rate, while barely influenced the fresh biomass of shoot and root. Moreover, both 1.5% and 3% biochar addition showed no significant difference in the fruit shape index of cherry radish compared to the control treatment. These results suggested that the biochar application alone could not improve the cherry radish growth in this tested soil. Thus, application of biochar combined with fertilizer or composted with organic wastes should be taken into account for this soil.

Direct shoot organogenesis of Digitalis trojana Ivan., an endemic ...

African Journals Online (AJOL)

STORAGESEVER

2010-03-15

Mar 15, 2010 ... An efficient protocol for in vitro propagation of Digitalis trojana Ivan. was developed via adventitious shoot regeneration. Leaf explants were cultured on MS which were supplemented with different concentrations of NAA (0.1, 0.5, 1.0 mg/ml) and BAP (0.1, 0.5, 1.0, 3.0, 5.0 mg/ml) for shoot formation.

Translocation of sorbitol and other photosynthates in golden delicious apple shoots

International Nuclear Information System (INIS)

Steenkamp, J.; Terblanche, J.H.; De Villiers, O.T.

1982-01-01

This study was undertaken to determine to what extent sorbitol and other photosynthates are translocated in Golden Delicious apple shoots. The distribution of radioactivity in the different fractions, after the leaves had been exposed to radiocarbon, was found in segment of the shoots directly below the treatment leaves. The highest 14 C activity was in the carbohydrate fraction. The results indicate that sorbitol is the principal carbohydrate transported in Golden Delicious apple shoots

Influence of calcium content of tissue on hyperhydricity and shoot-tip necrosis of in vitro regenerated shoots of Lavandula angustifolia Mill.

Directory of Open Access Journals (Sweden)

Marília Pereira Machado

2014-10-01

Full Text Available In the present study, the effects of two CaCl2.2H2O levels (440 and 1320 mg L-1 and two subcultures were evaluated on in vitro shoots of Lavandula angustifolia cv. Provence Blue. Ca2+ content of the apical, middle and basal portion of shoots was determined. Increasing CaCl2.2H2O level in the culture medium increased tissue Ca2+ content and decreased hyperhydricity. Shoot-tip necrosis also decreased with 1320 mg L-1 CaCl2.2H2O, but it did not occur in the second subculture. The middle and basal portion had higher Ca2+ content than apical portion. In non-hyperhydric tissues, there were smaller and more juxtaposed cells. Scanning electron microscopy of the leaves demonstrated that trichomes from in vitro leaf surface occurred in smaller quantities.

The growth and survival of plants in urban green roofs in a dry climate.

Science.gov (United States)

Razzaghmanesh, M; Beecham, S; Kazemi, F

2014-04-01

Green roofs as one of the components of water-sensitive urban design have become widely used in recent years. This paper describes performance monitoring of four prototype-scale experimental green roofs in a northern suburb of Adelaide, South Australia, undertaken over a 1-year period. Four species of indigenous Australian ground cover and grass species comprising Carpobrotus rossii, Lomandra longifolia 'Tanika,' Dianella caerula 'Breeze' and Myoporum parvifolium were planted in extensive and intensive green roof configurations using two different growing media. The first medium consisted of crushed brick, scoria, coir fibre and composted organics while the second comprised scoria, composted pine bark and hydro-cell flakes. Plant growth indices including vertical and horizontal growth rate, leaf succulence, shoot and root biomasses, water use efficiency and irrigation regimes were studied during a 12-month period. The results showed that the succulent species, C. rossii, can best tolerate the hot, dry summer conditions of South Australia, and this species showed a 100% survival rate and had the maximum horizontal growth rate, leaf succulence, shoot biomass and water use efficiency. All of the plants in the intensive green roofs with the crushed brick mix media survived during the term of this study. It was shown that stormwater can be used as a source of irrigation water for green roofs during 8 months of the year in Adelaide. However, supplementary irrigation is required for some of the plants over a full annual cycle. Copyright © 2014 Elsevier B.V. All rights reserved.

Crescimento radicular e aéreo de cultivares de arroz de terras altas em função da calagem Root and shoot growth of upland rice cultivars as affected by lime application

Directory of Open Access Journals (Sweden)

Carlos Alexandre Costa Crusciol

2012-01-01

Full Text Available O presente trabalho teve como objetivo avaliar o crescimento radicular e da parte aérea, além da eficiência de absorção de nutrientes pelas cultivares de arroz Caiapó e Maravilha, em função da calagem. O experimento foi desenvolvido em casa de vegetação, sendo os tratamentos constituídos pelas cultivares Caiapó e Maravilha combinadas com os índices de saturação por bases (V% de 10, 40 e 70. O delineamento experimental utilizado foi inteiramente casualizado, com quatro repetições. Foram avaliados o número de perfilhos, comprimento radicular, matéria seca de raízes, folhas e colmos, o teor foliar e a eficiência de absorção dos macronutrientes. De forma geral, observou-se que a cultivar moderna superou a tradicional em matéria seca de raízes, comprimento radicular, número de colmos, matéria seca de colmos e da parte aérea, além de acumular mais nutrientes a cultivar tradicional, mesmo nas condições de maior acidez. No entanto, os teores de nutrientes foram maiores na cultivar Caiapó. A cultivar Maravilha possui maior crescimento radicular e da parte aérea, nos diversos níveis de acidez, enquanto a Caiapó tem maior eficiência de absorção dos nutrientes do solo. A V% de 40 é a mais efetiva para ambas as cultivares.This work aimed to evaluate root growth, shoot development and nutrient absorption efficiency by rice cultivars Caiapó and Maravilha as affected by lime application. The experiment was carried out in a greenhouse, with treatments set up by Caiapó and Maravilha cultivars in combination with the base saturation (V% of 10%, 40% and 70%. The experiment was in a randomized complete block design, with four replications. The number of tillers, root length, root dry matter, leaves and stems, leaf content and macronutrients absorption efficiency were evaluated. Comparing cultivars, Maravilha cultivar presented higher root dry weight, root length, number of stems, dry matter of stems and shoot than Caiap

Foliar Sprays of Citric Acid and Malic Acid Modify Growth, Flowering, and Root to Shoot Ratio of Gazania (Gazania rigens L.: A Comparative Analysis by ANOVA and Structural Equations Modeling

Directory of Open Access Journals (Sweden)

Majid Talebi

2014-01-01

Full Text Available Foliar application of two levels of citric acid and malic acid (100 or 300 mg L−1 was investigated on flower stem height, plant height, flower performance and yield indices (fresh yield, dry yield and root to shoot ratio of Gazania. Distilled water was applied as control treatment. Multivariate analysis revealed that while the experimental treatments had no significant effect on fresh weight and the flower count, the plant dry weight was significantly increased by 300 mg L−1 malic acid. Citric acid at 100 and 300 mg L−1 and 300 mg L−1 malic acid increased the root fresh weight significantly. Both the plant height and peduncle length were significantly increased in all applied levels of citric acid and malic acid. The display time of flowers on the plant increased in all treatments compared to control treatment. The root to shoot ratio was increased significantly in 300 mg L−1 citric acid compared to all other treatments. These findings confirm earlier reports that citric acid and malic acid as environmentally sound chemicals are effective on various aspects of growth and development of crops. Structural equations modeling is used in parallel to ANOVA to conclude the factor effects and the possible path of effects.

Root-to-shoot hormonal communication in contrasting rootstocks suggests an important role for the ethylene precursor aminocyclopropane-1-carboxylic acid in mediating plant growth under low-potassium nutrition in tomato

Directory of Open Access Journals (Sweden)

Cristina Martínez-Andújar

2016-11-01

Full Text Available Selection and breeding of rootstocks that can tolerate low K supply may increase crop productivity in low fertility soils and reduce fertilizer application. However, the underlying physiological traits are still largely unknown. In this study, 16 contrasting recombinant inbred lines (RILs derived from a cross between domestic and wild tomato species (Solanum lycopersicum x S. pimpinellifolium have been used to analyse traits related to the rootstock-mediated induction of low (L, low shoot fresh weight or high (H, high shoot fresh weight vigour to a commercial F1 hybrid grown under control (6 mM, c and low-K (1mM, k. Based on hormonal and ionomic composition in the root xylem sap and the leaf nutritional status after long-term (7 weeks exposure low-K supply, a model can be proposed to explain the rootstocks effects on shoot performance with the ethylene precursor aminocyclopropane-1-carboxylic acid (ACC playing a pivotal negative role. The concentration of this hormone was higher in the low-vigour Lc and Lk rootstocks under both conditions, increased in the sensitive HcLk plants under low-K while it was reduced in the high-vigour Hk ones. Low ACC levels would promote the transport of K vs Na in the vigorous Hk grafted plants. Along with K, Ca and S, micronutrient uptake and transport were also activated in the tolerant Hk combinations under low-K. Additionally, an interconversion of trans-zeatin into trans-zeatin riboside would contribute to decrease ACC in the tolerant LcHk plants. The high vigour induced by the Hk plants can also be explained by an interaction of ACC with other hormones (cytokinins and salicylic, abscisic and jasmonic acids. Therefore, Hk rootstocks convert an elite tomato F1 cultivar into a (micro nutrient-efficient phenotype, improving growth under reduced K fertilization.

The Sandy Hook Elementary School shooting as tipping point

Science.gov (United States)

Shultz, James M; Muschert, Glenn W; Dingwall, Alison; Cohen, Alyssa M

2013-01-01

Among rampage shooting massacres, the Sandy Hook Elementary School shooting on December 14, 2012 galvanized public attention. In this Commentary we examine the features of this episode of gun violence that has sparked strong reactions and energized discourse that may ultimately lead toward constructive solutions to diminish high rates of firearm deaths and injuries in the United States. PMID:28228989

Natural genetic variation in Arabidopsis for responsiveness to plant growth-promoting rhizobacteria

NARCIS (Netherlands)

Wintermans, Paul C A; Bakker, Peter A H M; Pieterse, Corné M J

The plant growth-promoting rhizobacterium (PGPR) Pseudomonas simiae WCS417r stimulates lateral root formation and increases shoot growth in Arabidopsis thaliana (Arabidopsis). These plant growth-stimulating effects are partly caused by volatile organic compounds (VOCs) produced by the bacterium.

Natural genetic variation in Arabidopsis for responsiveness to plant growth-promoting rhizobacteria

NARCIS (Netherlands)

Wintermans, P.C.A.; Bakker, P.A.H.M.; Pieterse, C.M.J.

2016-01-01

The plant growth-promoting rhizobacterium (PGPR) Pseudomonas simiae WCS417r stimulates lateral root formation and increases shoot growth in Arabidopsis thaliana (Arabidopsis). These plant growth-stimulating effects are partly caused by volatile organic compounds (VOCs) produced by the bacterium.

Gene expression in arabidopsis shoot tips after liquid nitrogen exposure

Science.gov (United States)

Arabidopsis thaliana shoot tips can be successfully cryopreserved using either Plant Vitrification Solution 2 (PVS2) or Plant Vitrification Solution 3 (PVS3) as the cryoprotectant. We used this model system to identify suites of genes that were either upregulated or downregulated as shoot tips recov...

Cryopreservation of in vitro -grown shoot tips of apricot ( Prunus ...

African Journals Online (AJOL)

In vitro grown apricot (Prunus armeniaca L.) cv. El-Hamawey shoot tips were successfully cryopreserved using an encapsulation-dehydration procedure. Shoot tips were encapsulated in calcium-alginate beads before preculture on woody plant (WP) medium supplemented with different sucrose concentrations; 0.1, 0.3, 0.5, ...

Bamboo shoot preservation for enhancing its business potential and local economy: a review.

Science.gov (United States)

Bal, Lalit M; Singhal, Poonam; Satya, Santosh; Naik, S N; Kar, Abhijit

2012-01-01

Bamboo shoot as food has been used in traditional ways by the tribal community the world over. For enhancing its business potential, research on various aspects of bamboo shoot as food is being carried out in Japan, Taiwan, Thailand, and Asian countries and several products are available in the market. Bamboo shoots are used as a delicacy in human food, are a good source of dietary fiber, low in fat and calories. The research studies included in this review paper focus on post-harvest preservation of bamboo shoot. In view of the seasonal availability of bamboo shoot, the post-harvest preservation system for handling cynogenic toxicity in raw shoot while keeping nutrients intact and enhancement of shelf life of the value added products assume great significance for the business potential of this natural product. A yardstick of assessing the "Shelf life-Quality Matrix" developed in this review paper would give a new perspective of quality control in case of preservation of bamboo shoot. Also, knowledge gaps identified in this paper would give impetus to new academic and R&D activities, in turn generating an innovative job profile in the food industry as well as rural entrepreneurship.

Application of soybean shoot-cutting in SMV-resistance genetic analysis

Institute of Scientific and Technical Information of China (English)

Haifeng Chen; Zhihui Shan; Xin'an zhou; Zhonglu Yang; Qiao Wan; Yanyan Yang; Shuilian Chen; Chanjuan Zhang; Limiao Chen; Songli Yuan; Dezhen Qiu

2016-01-01

Soybean mosaic virus (SMV) is one of the most serious diseases affecting soy-bean yield. Recombination inbred lines (RILs) are common materials for resistance genetic research. However, the population construction always takes quite a long time which pro-long the breading process. Shoot-cutting is a well-established technique for plant multipli-cation. It has high successful ratio in soybean. In this study, we use shoot-cutting to multiply two F2 populations from the crosses of susceptible and resistant varieties. Soybean plants can be multiplied from 1 into 3 homogenous ones within 30 days, bringing on well-grown plants with normal seeds. The SMV resistance from cutting-shoot plants was consistent with that from original plants. When shoot-cutting is applied in a F2 population, the pheno-typic and genotypic data can be simultaneously collected and corresponding saved during population development. The genetic research and resistant breeding can be effectively promoted by this technology.

(Plant growth with limited water)

Energy Technology Data Exchange (ETDEWEB)

1991-01-01

The work supported by DOE in the last year built on our earlier findings that stem growth in soybean subjected to limited water is inhibited first by a physical limitation followed in a few hours by metabolic changes that reduce the extensibility of the cell walls. With time, there is modest recovery in extensibility and a 28kD protein accumulates in the walls of the growth-affected cells. A 31kD protein that was 80% similar in amino acid sequence also was present but did not accumulate in the walls of the stem cells. Explorations of the mRNA for these proteins showed that the mRNA for the 28kD protein increased in the shoot in response to water deprivation but the mRNA for the 31kD protein did not accumulate. In contrast, the roots continued to grow and the mRNA for the 31kD protein accumulated but the mRNA for the 28kD protein was undetectable. We also explored how growth occurs in the absence of an external water supply. We found that, under these conditions, internal water is mobilized from surrounding nongrowing or slowly growing tissues and is used by rapidly growing cells. We showed that a low water potential is normally present in the enlarging tissues and is the likely force that extracts water from the surrounding tissues. We found that it involved a gradient in water potential that extended from the xylem to the outlying cells in the enlarging region and was not observed in the slowly growing basal tissue of the stems of the same plant. The gradient was measured directly with single cell determinations of turgor and osmotic potential in intact plants. The gradient may explain instances of growth inhibition with limited water when there is no change in the turgor of the enlarging cells. 17 refs.

Effect of growth regulators in meristem culture of potato (solanum tuberosmum l.)

International Nuclear Information System (INIS)

Batool, A.; Zaidi, S.S.H.

2014-01-01

Two growth regulators, viz., Gibberellic acid (GA3) and Naphthalene acetic acid (NAA) and a combination of both (GA3 and NAA) were evaluated at three different levels (200, 300 and 400 meul) to check the growth rate of root, shoot, number of leaves and nodes of potato plantlets in two potato varieties, namely cardinal and SH-5, grown by meristem culture. Analysis of variance revealed highly significant differences between varieties, hormones and their interaction for all the studied traits. Mean values revealed that among two varieties Cardinal produced root length (0.70 cm), shoot length (2.50 cm), number of leaves (6.96) and number of nodes (8) are better than the SH-5 which produced root length (0.54 cm), shoot length (1.38 cm), number of leaves (4.29) and number of nodes (5.3). The variety cardinal and GA3 at 300 meul followed by 200 meul produced most suitable results. By using the concentration of 300 meul maximum root length of (1.40 cm), shoot length of (3.43 cm), number of leaves (10) and no of nodes (11) was obtained. At 200 meul, though root and shoot length obtained was very similar at 300 meul but produced less number of leaves and nodes. (author)

Impact of plant growth promoting bacillus subtilis on growth and physiological parameters of bassia indica (indian bassia) grown udder salt stress

International Nuclear Information System (INIS)

Abeer, H.; Asma, A. H.; Allah, A.; Qarawi, A.; Shalawi, A.; Dilfuza, E.

2015-01-01

In this study, the role of a salt-tolerant plant growth-promoting bacterium (PGPR), Bacillus subtilis, in the alleviation of salinity stress during the growth of Indian bassia (Bassia indica (Wight) A.J. Scott), was studied under ccontrolled growth chamber conditions following seed inoculation. Physiological parameters such as neutral and phospholipids, fatty acid composition as well as photosynthetic pigments, were investigated. Salinity inhibited shoot and root length by 16 and 42 percentage, dry weight by 37 and 23 percentage respectively and negatively affected physiological parameters. Inoculation of unstressed and salt-stressed Indian bassia with B. subtilis significantly improved root and shoot growth, total lipid content, the phospholipid fraction, photosynthetic pigments (chlorophyll a and b and carotenoid contents) and also increased oleic (C 18:1 ), linoleic (C 18:2 ) and linolenic (C 18:3 ) acids in plant leaves compared to uninoculated plants. The salt-tolerant PGPR, B. subtilis could act synergistically to promote the growth and fitness of Indian bassia plants under salt stress by providing an additional supply of an auxin (IAA) and induce salt stress resistance by reducing stress ethylene levels. (author)

beta-Blockade used in precision sports: effect on pistol shooting performance.

Science.gov (United States)

Kruse, P; Ladefoged, J; Nielsen, U; Paulev, P E; Sørensen, J P

1986-08-01

In a double-blind cross-over study of 33 marksmen (standard pistol, 25 m) the adrenergic beta 1-receptor blocker, metoprolol, was compared to placebo. Metoprolol obviously improved the pistol shooting performance compared with placebo. Shooting improved by 13.4% of possible improvement (i.e., 600 points minus actual points obtained) as an average (SE = 4%, 2P less than 0.002). The most skilled athletes demonstrated the clearest metoprolol improvement. We found no correlation between the shooting improvement and changes in the cardiovascular variables (i.e., changes of heart rate and systolic blood pressure) and no correlation to the estimated maximum O2 uptake. The shooting improvement is an effect of metoprolol on hand tremor. Emotional increase of heart rate and systolic blood pressure seem to be a beta 1-receptor phenomenon.

Morphological and physiological photon flux influence under in vitro culture of apple shoots

Directory of Open Access Journals (Sweden)

Ilisandra Zanandrea

2009-10-01

Full Text Available The aim of the present study was to evaluate the growth and development of apple rootstock shoots submitted to different photon flux densities (7, 14, 21 and 60 µmol m-2 s-1 and three culture media. The best photon flux for maximizing growth, number of shoots and leaves was 14 µmol m-2 s-1, which also resulted in the highest values of chloroplastic pigments. On the other hand, the highest photon flux (60 µmol m-2 s-1 decreased significantly these parameters. Medium with reduced sucrose concentration did not affect the analyzed parameters, enabling an efficient multiplication of the cultivar with only 1% of sucrose.O objetivo do presente estudo foi avaliar características de crescimento e desenvolvimento de brotações de macieira submetidas a diferentes densidades de fluxo de fótons (7, 14, 21 e 60 µmol m-2 s-1 e três meios de cultura. O melhor fluxo de fótons para maximizar o crescimento, número de brotações e de folhas foi de 14 µmol m-2 s-1, o qual também proporcionou os maiores valores de pigmentos cloroplastídicos. Por outro lado, alto fluxo de fótons (60 µmol m-2 s-1 diminuiu significativamente os parâmetros citados acima. O meio com concentração reduzida de sacarose não afetou os parâmetros analisados, possibilitando uma multiplicação eficiente desta cultivar com apenas 1% deste carboidrato.

The Effect of Plant Growth Regulators on Callus Induction and Regeneration of Amygdalus communis

Directory of Open Access Journals (Sweden)

Naimeh SHARIFMOGHADAM

2011-08-01

Full Text Available The Almond (Amygdalus communis is one of the most important and oldest commercial nut crops, belonging to the Rosaceae family. Almond has been used as base material in pharmaceutical, cosmetic, hygienically and food industry. Propagation by tissue culture technique is the most important one in woody plants. In the current research, in vitro optimization of tissue culture and mass production of almond was investigated. In this idea, explants of actively growing shoots were collected and sterilized, then transferred to MS medium with different concentrations and combinations of plant growth regulators. The experiment was done in completely randomized blocks design, with 7 treatment and 30 replications. After 4 weeks, calli induction, proliferation, shoot length and number of shoot per explants were measured. Results showed that the best medium for shoot initiation and proliferation was MS + 0.5 mg/l IAA (Indol-3-Acetic Acid + 1 mg/l BA (Benzyl Adenine. Autumn was the best season for collecting explants. The shoots were transferred to root induction medium with different concentrations of plant growth regulators. The best root induction medium was MS + 0.5 mg/l IBA (Indol Butyric Acid.

Multifarious plant growth promotion by an entomopathogenic fungus Lecanicillium psalliotae.

Science.gov (United States)

Senthil Kumar, C M; Jacob, T K; Devasahayam, S; Thomas, Stephy; Geethu, C

2018-03-01

An entomopathogenic fungus, Lecanicillium psalliotae strain IISR-EPF-02 previously found infectious to cardamom thrips, Sciothrips cardamomi promoted plant growth in cardamom, Elettaria cardamomum. The isolate exhibited direct plant growth promoting traits by production of indole-3-acetic acid and ammonia and by solubilizing inorganic phosphate and zinc. It also showed indirect plant growth promoting traits by producing siderophores and cell wall-degrading enzymes like, α-amylases, cellulases and proteases. In pot culture experiments, application of the fungus at the root zone of cardamom seedlings significantly increased shoot and root length, shoot and root biomass, number of secondary roots and leaves and leaf chlorophyll content compared to untreated plants. This is the first report on the plant growth promoting traits of this fungus. The entomopathogenic and multifarious growth promoting traits of L. psalliotae strain IISR-EPF-02 suggest that it has great potential for exploitation in sustainable agriculture. Copyright © 2017 Elsevier GmbH. All rights reserved.

Seed Germination and Cuttings Growth of Piper Aduncum

Science.gov (United States)

Susanto, D.; Sudrajat; Suwinarti, W.; Amirta, R.

2018-04-01

Sirih hutan (Piper aduncum L) is one of group shurbs tropical species, has potential to be developed as raw material of biomass based electricity. The aim of this research was to know seed germination and cuttings growth of P. aduncum plant as the first step in cultivation of this plant. Observation of flowers and fruits were done in secondary forest, while seed germination and growth of shoot cuttings were done in the laboratory. The results showed that P. aduncum seeds can be germinated in a relatively short time of 17 to 25 days with a fairly high germination percentage of 90 ± 8.16% and germination rate of 4.7 ± 0.34%. The growth of seedlings at 2 months old was 4.78 ± 0.42 cm, plant height 3.97 ± 0.27 cm, and relative growth rate 0.33 ± 0.14%. The treatment of synthetic growth regulator had significant effect on shoot growth and root number on the plant stem cuttings. Preparation of seedlings ready to plant in a generative and vegetative for cultivation of these plants in the experimental plot.

Soil pollution at outdoor shooting ranges: Health effects, bioavailability and best management practices.

Science.gov (United States)

Fayiga, A O; Saha, U K

2016-09-01

The total lead (Pb) concentrations of the surface soil, sub surface soil, vegetation and surface waters of outdoor shooting ranges are extremely high and above regulatory limits. Lead is dangerous at high concentrations and can cause a variety of serious health problems. Shooters and range workers are exposed to lead dust and can even take Pb dust home to their families while some animals around the shooting range can ingest the Pb bullets. The toxicity of Pb depends on its bioavailability which has been determined to be influenced greatly by the geochemical properties of each site. The bioavailability of Pb in shooting ranges has been found to be higher than other metal contaminated soils probably because of its very low residual Pb (soil, migration of Pb within shooting ranges and offsite has been reported in literature. Best management practices to reduce mobility of Pb in shooting ranges involve an integrated Pb management program which has been described in the paper. The adoption of the non-toxic "green bullet" which has been developed to replace Pb bullets may reduce or prevent environmental pollution at shooting ranges. However, the contaminated soil resulting from decades of operation of several shooting ranges still needs to be restored to its natural state. Copyright © 2016 Elsevier Ltd. All rights reserved.

Disruption of the rice nitrate transporter OsNPF2.2 hinders root-to-shoot nitrate transport and vascular development

Science.gov (United States)

Li, Yuge; Ouyang, Jie; Wang, Ya-Yun; Hu, Rui; Xia, Kuaifei; Duan, Jun; Wang, Yaqin; Tsay, Yi-Fang; Zhang, Mingyong

2015-01-01

Plants have evolved to express some members of the nitrate transporter 1/peptide transporter family (NPF) to uptake and transport nitrate. However, little is known of the physiological and functional roles of this family in rice (Oryza sativa L.). Here, we characterized the vascular specific transporter OsNPF2.2. Functional analysis using cDNA-injected Xenopus laevis oocytes revealed that OsNPF2.2 is a low-affinity, pH-dependent nitrate transporter. Use of a green fluorescent protein tagged OsNPF2.2 showed that the transporter is located in the plasma membrane in the rice protoplast. Expression analysis showed that OsNPF2.2 is nitrate inducible and is mainly expressed in parenchyma cells around the xylem. Disruption of OsNPF2.2 increased nitrate concentration in the shoot xylem exudate when nitrate was supplied after a deprivation period; this result suggests that OsNPF2.2 may participate in unloading nitrate from the xylem. Under steady-state nitrate supply, the osnpf2.2 mutants maintained high levels of nitrate in the roots and low shoot:root nitrate ratios; this observation suggests that OsNPF2.2 is involved in root-to-shoot nitrate transport. Mutation of OsNPF2.2 also caused abnormal vasculature and retarded plant growth and development. Our findings demonstrate that OsNPF2.2 can unload nitrate from the xylem to affect the root-to-shoot nitrate transport and plant development. PMID:25923512

Effect of soil acidification on root growth, nutrient and water uptake

International Nuclear Information System (INIS)

Marschner, H.

1989-01-01

Soil acidification poses various types of stress to plants, especially Al and H + toxicity in roots and Mg and Ca deficiency in roots and shoots. The importance of the various types of stress varies with plant species, location and time. Average data of the chemical composition of the bulk soil or of the molar Ca/Al or Mg/Al ratios in the soil solution without consideration of the Al species are of limited value for precise conclusions of the actual, or for predictions of the potential risk of soil-acidity-induced inhibition of root growth and of nutritional imbalances. The root-induced changes in the rhizosphere and the consequences for Al toxicity and nutrient acquisition by plants deserve more attention. Further it should be considered that roots are not only required for anchoring higher plants in the soil and for nutrient and water uptake. Roots are also important sites for synthesis of phytohormones, cytokinins and abscisic acid in particular, which are transported into the shoots and act either as signals for the water status at the soil-root interface (ABA) or as compounds required for growth and development. Inhibition in root growth may therefore affect shoot growth by means other than water and nutrient supply. (orig./vhe)

In vitro propagation of Stevia rebaudina plants using multiple shoot culture.

Science.gov (United States)

Nepovím, A; Vanek, T

1998-12-01

A multiple shoot culture was induced from nodal segments on MS medium containing half concentration of macroelements, 1% sucrose, and supplemented with NAA (0.01 mg/l). A bioreactor with hormone-free MS medium (300 ml) was inoculated with 1.5 g of the multiple shoot culture and cultivated for a month. The cultivating process of the multiple shoot culture in the bioreactor and the transfer into ex vitro conditions took about 8-9 weeks and produced approx. 600 new seedlings, that could be transferred from greenhouse to field conditions.

Carbon dioxide exchange in Norway spruce at the shoot, tree and ecosystem scale.

Science.gov (United States)

Wallin, G; Linder, S; Lindroth, A; Räntfors, M; Flemberg, S; Grelle, A

2001-08-01

Net CO2 exchange in a 35-year-old boreal Norway spruce (Picea abies (L.) Karst.) forest in northern Sweden was measured at the shoot (NSE), tree (NTE) and ecosystem levels (NEE) by means of shoot cuvettes, whole-tree chambers and the eddy covariance technique, respectively. We compared the dynamics of gross primary production (GPP) at the three levels during the course of a single week. The diurnal dynamics of GPP at each level were estimated by subtracting half-hourly or hourly model-estimated values of total respiration (excluding light-dependent respiration) from net CO(2) exchange. The relationship between temperature and total respiration at each level was derived from nighttime measurements of NSE, NTE and NEE over the course of 1 month. There was a strong linear relationship (r2 = 0.93) between the hourly estimates of GPP at the shoot and tree levels, but the correlation between shoot- and ecosystem-level GPP was weaker (r2 = 0.69). However, the correlation between shoot- and ecosystem-level GPP was improved (r2 = 0.88) if eddy covariance measurements were restricted to periods when friction velocity was > or = 0.5 m s(-1). Daily means were less dependent on friction velocity, giving an r2 value of 0.94 between shoot- and ecosystem-level GPP. The correlation between shoot and tree levels also increased when daily means were compared (r2 = 0.98). Most of the measured variation in carbon exchange rate among the shoot, tree and ecosystem levels was the result of periodic low coupling between vegetation and the atmosphere at the ecosystem level. The results validate the use of measurements at the shoot and tree level for analyzing the contribution of different compartments to net ecosystem CO2 exchange.

Capability and opportunity in hot shooting performance: Evidence from top-scoring NBA leaders.

Science.gov (United States)

Chang, Shun-Chuan

2018-01-01

In basketball games, whenever players successfully shoot in streaks, they are expected to demonstrate heightened performance for a stretch of time. Streak shooting in basketball has been debated for more than three decades, but most studies have provided little significant statistical evidence and have labeled random subjective judgments the "hot hand fallacy." To obtain a broader perspective of the hot hand phenomenon and its accompanying influences on the court, this study uses field goal records and optical tracking data from the official NBA database for the entire 2015-2016 season to analyze top-scoring leaders' shooting performances. We first reflect on the meaning of "hot hand" and the "Matthew effect" in actual basketball competition. Second, this study employs statistical models to integrate three different shooting perspectives (field goal percentage, points scored, and attempts). This study's findings shed new light not only on the existence or nonexistence of streaks, but on the roles of capability and opportunity in NBA hot shooting. Furthermore, we show how hot shooting performances resulting from capability and opportunity lead to actual differences for teams.

Capability and opportunity in hot shooting performance: Evidence from top-scoring NBA leaders.

Directory of Open Access Journals (Sweden)

Shun-Chuan Chang

Full Text Available In basketball games, whenever players successfully shoot in streaks, they are expected to demonstrate heightened performance for a stretch of time. Streak shooting in basketball has been debated for more than three decades, but most studies have provided little significant statistical evidence and have labeled random subjective judgments the "hot hand fallacy." To obtain a broader perspective of the hot hand phenomenon and its accompanying influences on the court, this study uses field goal records and optical tracking data from the official NBA database for the entire 2015-2016 season to analyze top-scoring leaders' shooting performances. We first reflect on the meaning of "hot hand" and the "Matthew effect" in actual basketball competition. Second, this study employs statistical models to integrate three different shooting perspectives (field goal percentage, points scored, and attempts. This study's findings shed new light not only on the existence or nonexistence of streaks, but on the roles of capability and opportunity in NBA hot shooting. Furthermore, we show how hot shooting performances resulting from capability and opportunity lead to actual differences for teams.

School Shootings as Organizational Deviance.

Science.gov (United States)

Fox, Cybelle; Harding, David J.

2005-01-01

This article argues that rampage school shootings in American public schools can be understood as instances of organizational deviance, which occurs when events created by or in organizations do not conform to an organization's goals or expectations and produce unanticipated and harmful outcomes. Drawing on data from qualitative case studies of…

Effect of Thorium on Growth and Uptake of Some Elements by Maize Plant

International Nuclear Information System (INIS)

Al-Shobaki, M.E.E.

2012-01-01

A pot experiment (sand culture) was carried out to investigate the effect of thorium on maize dry matter yield, contents and uptake of N,P ,K, Na and Fe and thorium accumulation in maize plant.The pots were contaminated by thorium as Thorium Nitrate(Th (NO 3 ) 4 ,H 2 O)at concentrations 0,5,10,11,12,13,14,15 and 50 ppm. Pots irrigated by 1/10 Hogland solution for 15 days, increased tol/4 Hogland solution after that.The results show that the dry matter (shoot, root and whole plant)decreased with increasing thorium concentration in soil up to 12 ppm and slightly increased with increasing Th to 13 ppm . The Nitrogen content and its uptake decreased with increasing thorium concentration in media growth up to 11 ppm .They were slightly increased at Th concentration between 11-14 ppm in maize shoot and root. The shoots always contained N-content and uptake more than that found in roots . P- uptake decreased in both shoots and roots with increasing in thorium concentration in media growth.

Fabrication of Microfiber Patterns with Ivy Shoot-Like Geometries Using Improved Electrospinning.

Science.gov (United States)

Jeong, Young Hun; Lee, Jongwan

2016-04-01

Fibers and fibrous structures are used extensively in various fields due to their many advantages. Microfibers, as well as nanofibers, are considered to be some of the most valuable forms of advanced materials. Accordingly, various methods for fabricating microfibers have been developed. Electrospinning is a useful fabrication method for continuous polymeric nano- and microfibers with attractive merits. However, this technique has limitations in its ability to control the geometry of fibrous structures. Herein, advanced electrospinning with direct-writing functionality was used to fabricate microfiber patterns with ivy shoot-like geometries after experimentally investigating the effects of the process conditions on the fiber formation. The surface properties of the fibers were also modified by introducing nanoscale pores through the use of higher levels of humidity during the fabrication process.

Antimony (SbIII) reduces growth, declines photosynthesis, and modifies leaf tissue anatomy in sunflower (Helianthus annuus L.).

Science.gov (United States)

Vaculík, Marek; Mrázová, Anna; Lux, Alexander

2015-12-01

The role of antimony (Sb)--a non-essential trace metalloid--in physiological processes running in crops is still poorly understood. Present paper describes the effect of Sb tartrate (SbIII) on growth, Sb uptake, photosynthesis, photosynthetic pigments, and leaf tissue organization in young sunflower plants grown in hydroponics. We found that growth of below- and aboveground part was reduced with increasing concentration of Sb in the medium. Although Sb was mostly taken up by sunflower roots and only small part (1-2%) was translocated to the shoots, decline in photosynthesis, transpiration, and decreased content of photosynthetic pigments were observed. This indicates that despite relatively low mobility of Sb in root-shoot system, Sb in shoot noticeably modifies physiological status and reduced plant growth. Additionally, leaf anatomical changes indicated that Sb reduced the size of intercellular spaces and made leaf tissue more compact.

School Shootings and Critical Pedagogy

Science.gov (United States)

Schiller, Juliet

2013-01-01

What has been left out of studying school violence and shootings is a comprehensive look at the culture that creates violence and the lack of support for those deemed "different" in an educational setting that promotes and rewards competition. If parents, teachers, and other adults associated with children were teaching the values of…

Anomalous needle numbers on dwarf shoots of Pinus mugo and P. uncinata (Pinaceae

Directory of Open Access Journals (Sweden)

Krystyna Boratyńska

2011-01-01

Full Text Available The frequency of occurrence of abnormal, three- (or more needle dwarf shoots of most southern and central European two-needle pine (Pinus species were studied. No specimens with more than two-needle dwarf shoots were found in a population of P. nigra Arnold subsp. salzmannii (Dunal Franco from the Iberian Peninsula and in two populations of P. uliginosa Neumann from the Sudeten Mountains in Central Europe. Single specimens were found within one population of P. pinaster Aiton from the Iberian Peninsula and among six populations of P. sylvestris L. from the Iberian Peninsula and Central Europe. Abnormal dwarf shoots mostly with three, but also four, five or six needles were found among 24 of 25 surveyed populations of P. mugo Turra and P. uncinata Ramond. The average frequency of specimens with at least one three-needle dwarf shoot was 24% for P. mugo and 20% for P. uncinata. The frequencies of occurrence varied significantly among studied populations and were highest in samples collected from the upper elevational range limits of the species in the mountains and near the northern limits of their ranges. The frequency of abnormal dwarf shoots in the same populations was significantly high in 2-3 consecutive years. Needles from three-needle dwarf shoots were not significantly shorter than those of two-needle shoots.

Glyphosate (Ab)sorption by Shoots and Rhizomes of Native versus Hybrid Cattail (Typha).

Science.gov (United States)

Zheng, Tianye; Sutton, Nora B; de Jager, Pim; Grosshans, Richard; Munira, Sirajum; Farenhorst, Annemieke

2017-11-01

Wetlands in the Prairie Pothole Region of North America are integrated with farmland and contain mixtures of herbicide contaminants. Passive nonfacilitated diffusion is how most herbicides can move across plant membranes, making this perhaps an important process by which herbicide contaminants are absorbed by wetland vegetation. Prairie wetlands are dominated by native cattail (Typha latifolia) and hybrid cattail (Typha x glauca). The objective of this batch equilibrium study was to compare glyphosate absorption by the shoots and rhizomes of native versus hybrid cattails. Although it has been previously reported for some pesticides that passive diffusion is greater for rhizome than shoot components, this is the first study to demonstrate that the absorption capacity of rhizomes is species dependent, with the glyphosate absorption being significantly greater for rhizomes than shoots in case of native cattails, but with no significant differences in glyphosate absorption between rhizomes and shoots in case of hybrid cattails. Most importantly, glyphosate absorption by native rhizomes far exceeded that of the absorption occurring for hybrid rhizomes, native shoots and hybrid shoots. Glyphosate has long been used to manage invasive hybrid cattails in wetlands in North America, but hybrid cattail expansions continue to occur. Since our results showed limited glyphosate absorption by hybrid shoots and rhizomes, this lack of sorption may partially explain the poorer ability of glyphosate to control hybrid cattails in wetlands.

Developmental decline in height growth in Douglas-fir.

Science.gov (United States)

Barbara J. Bond; Nicole M. Czarnomski; Clifton Cooper; Michael E. Day; Michael S. Greenwood

2007-01-01

The characteristic decline in height growth that occurs over a tree's lifespan is often called "age-related decline." But is the reduction in height growth in aging trees a function of age or of size? We grafted shoot tips across different ages and sizes of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees to determine whether...

Developmental anatomy of blueberry (Vaccinium corymbosum L. ‘Aurora’) shoot regeneration

Science.gov (United States)

The culture of Vaccinium corymbosum L. ’Aurora’ leaves on regeneration medium results in the regeneration of adventitious shoots. We present anatomical evidence that these new shoot apices are directly regenerated from the cultured blades. Mounds of densely staining cells, which formed from epidermi...

Chlordecone Transfer and Distribution in Maize Shoots.

Science.gov (United States)

Pascal-Lorber, Sophie; Létondor, Clarisse; Liber, Yohan; Jamin, Emilien L; Laurent, François

2016-01-20

Chlordecone (CLD) is a persistent organic pollutant (POP) that was mainly used as an insecticide against banana weevils in the French West Indies (1972-1993). Transfer of CLD via the food chain is now the major mechanism for exposure of the population to CLD. The uptake and the transfer of CLD were investigated in shoots of maize, a C4 model plant growing under tropical climates, to estimate the exposure of livestock via feed. Maize plants were grown on soils contaminated with [(14)C]CLD under controlled conditions. The greatest part of the radioactivity was associated with roots, nearly 95%, but CLD was detected in whole shoots, concentrations in old leaves being higher than those in young ones. CLD was thus transferred from the base toward the plant top, forming an acropetal gradient of contaminant. In contrast, results evidenced the existence of a basipetal gradient of CLD concentration within leaves whose extremities accumulated larger amounts of CLD because of evapotranspiration localization. Extractable residues accounted for two-thirds of total residues both in roots and in shoots. This study highlighted the fact that the distribution of CLD contamination within grasses resulted from a conjunction between the age and evapotranspiration rate of tissues. CLD accumulation in fodder may be the main route of exposure for livestock.

Strategies of copper tolerance in root and shoot of broad bean (Vicia faba L.)

International Nuclear Information System (INIS)

Latef, A.A.H.; Alhmad, M.F.A.

2013-01-01

Changes in dry mass and some physiological parameters were investigated in root and shoot of broad bean (Vicia faba L.) exposed to different concentrations of CuSO/sub 4/ (0, 100, 200, 300 and 400 mg kg/sup -1/) for 15 days. Low Cu concentration did not affect dry mass of root and shoot. However, the negative effect of copper on dry mass was noticed in root than shoot especially at the higher concentrations of copper due to the accumulation of Cu was higher in root than that in shoot. Cu induced changes in the concentration of photosynthetic pigments, Zn, K and Ca. Exposure to Cu induced the accumulation of organic solutes (soluble sugar, soluble protein and total free amino acids) in root than shoot. Level of malondialdehyde (MDA) was correlated with the concentration of Cu in broad bean tissues. Copper stimulated the activity of superoxide dismutase (SOD) and peroxidase (POD) and this stimulation was more obvious in shoot than root. (author)

School Shootings in Policy Spotlight

Science.gov (United States)

Maxwell, Lesli A.

2006-01-01

The three school shootings that left a principal and six students dead in less than a week have sparked a barrage of pledges from national and state political leaders to tighten campus security. School safety experts urged caution against overreacting to the horrific, but rare, incidents in rural schools in Colorado, Pennsylvania, and Wisconsin.…

Effects of Droplet-Vitrification Cryopreservation Based on Physiological and Antioxidant Enzyme Activities of Brassidium Shooting Star Orchid

Directory of Open Access Journals (Sweden)

Safrina Rahmah

2015-01-01

Full Text Available Protocorm-like bodies (PLBs of Brassidium Shooting Star orchid were successfully cryopreserved using droplet-vitrification method. Vitrification based cryopreservation protocol is comprised of preculture, osmoprotection, cryoprotection, cooling, rewarming, and growth recovery and each and every step contributes to the achievement of successful cryopreservation. In order to reveal the lethal and nonlethal damage produced by cryopreservation, histological observation, scanning electron microscopy (SEM, and biochemical analysis were carried out in both cryopreserved and noncryopreserved PLBs of Brassidium Shooting Star orchid comparing with the control PLBs stock culture. Histological and scanning electron microscopy analyses displayed structural changes in cryopreserved PLBs due to the impact of cryoinjury during exposure to liquid nitrogen. Total soluble protein significantly increased throughout the dehydration process and the highest value was achieved when PLBs were stored in liquid nitrogen. Ascorbate peroxidase (APX and catalase (CAT showed the highest enzyme activities in both dehydration and cryostorage treatments indicating that stress level of PLBs was high during these stages.

Alleviation of salt stress by halotolerant and halophilic plant growth-promoting bacteria in wheat (Triticum aestivum

Directory of Open Access Journals (Sweden)

Furkan Orhan

Full Text Available ABSTRACT In the current study, 18 halotolerant and halophilic bacteria have been investigated for their plant growth promoting abilities in vitro and in a hydroponic culture. The bacterial strains have been investigated for ammonia, indole-3-acetic acid and 1-aminocyclopropane-1-carboxylate-deaminase production, phosphate solubilisation and nitrogen fixation activities. Of the tested bacteria, eight were inoculated with Triticum aestivum in a hydroponic culture. The investigated bacterial strains were found to have different plant-growth promoting activities in vitro. Under salt stress (200 mM NaCl, the investigated bacterial strains significantly increased the root and shoot length and total fresh weight of the plants. The growth rates of the plants inoculated with bacterial strains ranged from 62.2% to 78.1%.Identifying of novel halophilic and halotolerant bacteria that promote plant growth can be used as alternatives for salt sensitive plants. Extensive research has been conducted on several halophilic and halotolerant bacterial strains to investigate their plant growth promoting activities. However, to the best of my knowledge, this is the first study to inoculate these bacterial strains with wheat.

Alleviation of salt stress by halotolerant and halophilic plant growth-promoting bacteria in wheat (Triticum aestivum).

Science.gov (United States)

Orhan, Furkan

2016-01-01

In the current study, 18 halotolerant and halophilic bacteria have been investigated for their plant growth promoting abilities in vitro and in a hydroponic culture. The bacterial strains have been investigated for ammonia, indole-3-acetic acid and 1-aminocyclopropane-1-carboxylate-deaminase production, phosphate solubilisation and nitrogen fixation activities. Of the tested bacteria, eight were inoculated with Triticum aestivum in a hydroponic culture. The investigated bacterial strains were found to have different plant-growth promoting activities in vitro. Under salt stress (200mM NaCl), the investigated bacterial strains significantly increased the root and shoot length and total fresh weight of the plants. The growth rates of the plants inoculated with bacterial strains ranged from 62.2% to 78.1%. Identifying of novel halophilic and halotolerant bacteria that promote plant growth can be used as alternatives for salt sensitive plants. Extensive research has been conducted on several halophilic and halotolerant bacterial strains to investigate their plant growth promoting activities. However, to the best of my knowledge, this is the first study to inoculate these bacterial strains with wheat. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Capability and opportunity in hot shooting performance: Evidence from top-scoring NBA leaders

Science.gov (United States)

2018-01-01

In basketball games, whenever players successfully shoot in streaks, they are expected to demonstrate heightened performance for a stretch of time. Streak shooting in basketball has been debated for more than three decades, but most studies have provided little significant statistical evidence and have labeled random subjective judgments the “hot hand fallacy.” To obtain a broader perspective of the hot hand phenomenon and its accompanying influences on the court, this study uses field goal records and optical tracking data from the official NBA database for the entire 2015–2016 season to analyze top-scoring leaders’ shooting performances. We first reflect on the meaning of “hot hand” and the “Matthew effect” in actual basketball competition. Second, this study employs statistical models to integrate three different shooting perspectives (field goal percentage, points scored, and attempts). This study’s findings shed new light not only on the existence or nonexistence of streaks, but on the roles of capability and opportunity in NBA hot shooting. Furthermore, we show how hot shooting performances resulting from capability and opportunity lead to actual differences for teams. PMID:29432458

In vitro shoot regeneration and microcorm development in crocus vernus (l.) hill

International Nuclear Information System (INIS)

Sivanesan, I.

2014-01-01

An efficient method has been developed for In vitro regeneration of shoot and microcorm from corm explants of Crocus vernus. Corms were cut into 0.5-1.0 cm long segments and cultured on the SH medium supplemented with 0.5, 1.0, 2.0, or 4.0 mg L-1 2-isopentyl adenine (2-iP), N6-benzyladenine (BA), and N6-furfuryladenine (kinetin, Kin) alone or combination with 0.5 or 1.0 mg L-1 alpha-naphthalene acetic acid (NAA) for shoot regeneration. Of the three cytokinins tested, BA was found to be the most effective cytokinin for shoot formation. The number of shoots induced per explant was more when BA was combined with 0.5 mg L-1 NAA than with 1.0 mg L-1 NAA. The greatest percentage of shoot induction (97.2) with the mean number of 11.8 shoots per explant was obtained when the SH medium was supplemented with 2.0 mg L-1 BA and 0.5 mg L-1 NAA. The frequency of microcorm induction was significantly affected by the concentrations of sucrose.The greatest number of 6.1 microcorms per explant was obtained when the SH medium was supplemented with 2.0 mg L-1 BA, 0.5 mg L-1 NAA and 6.0% sucrose. The microcorms formed In vitro developed daughter corms when they were cultured on this medium. Microcorms were separated from the culture and planted out in acclimatization boxes containing a commercial medium. About 85% of corms developed shoot and root after 30 days. This protocol could be utilized for genetic transformation and mass clonal propagation of C. (author)

Solution of Constrained Optimal Control Problems Using Multiple Shooting and ESDIRK Methods

DEFF Research Database (Denmark)

Capolei, Andrea; Jørgensen, John Bagterp

2012-01-01

of this paper is the use of ESDIRK integration methods for solution of the initial value problems and the corresponding sensitivity equations arising in the multiple shooting algorithm. Compared to BDF-methods, ESDIRK-methods are advantageous in multiple shooting algorithms in which restarts and frequent...... algorithm. As we consider stiff systems, implicit solvers with sensitivity computation capabilities for initial value problems must be used in the multiple shooting algorithm. Traditionally, multi-step methods based on the BDF algorithm have been used for such problems. The main novel contribution...... discontinuities on each shooting interval are present. The ESDIRK methods are implemented using an inexact Newton method that reuses the factorization of the iteration matrix for the integration as well as the sensitivity computation. Numerical experiments are provided to demonstrate the algorithm....

Development of Sirococcus shoot blight following thinning in western hemlock regeneration.

Science.gov (United States)

Charles G. Shaw; Thomas H. Laurent; Spencer. Israelson

1981-01-01

Shoot mortality from Sirococcus strobilinus Preuss. and other causes was recorded by crown position from April 1978 through October 1979 in younggrowth western hemlock (Tsuga heterophylla (Raf.) Sarg.) crop trees released in a 1977 thinning at Thomas Bay, Alaska. All study trees contained some infected shoots, but no terminal...

Shoot growth, radiation interception and dry matter production and partitioning during the establishment phase of Miscanthus sinensis 'Giganteus' grown at two densities in the UK

International Nuclear Information System (INIS)

Bullard, M.J.; Heath, M.C.; Nixon, P.M.I.

1995-01-01

Photosynthetic area index (PAI), radiation interception (I) and dry matter partitioning between shoots and roots were measured for Miscanthus sinensis‘Giganteus' grown from micro-propagated transplants on a fertile peaty loam soil in eastern England. In the establishment year, Miscanthus plants produced 35 and 70 shoots plant -1 at densities of 4.0 and 1.8 plants m -2 respectively. At the higher density, there were 140 shoots m -2 with the largest reaching a height of 1.8 m; these canopies attained a maximum PAI of 5.45, intercepting 94% of incident radiation. Leaf lamina contributed c. 90% of total photosynthetic area with stems contributing the remainder. At the lower density, maximum PAI and I values were 2.88 and 86% respectively. PAI was related to I by calculating attenuation coefficients (k); these indicated that Miscanthus canopies were more effective at intercepting radiation per unit PAI at the lower density (k= -0.31) compared with the higher density (k= -0.20). Radiation interception was related to dry matter accumulated by calculating conversion efficiencies (e). At 4 plants m -2 , × for shoot dry matter production was 1.17g MJ -1 . Miscanthus partitioned a relatively large amount of total dry matter into below-ground biomass. By plant senescence, c. 30% of total dry matter had been partitioned into root and rhizome; rhizome biomass contributed 80% of below-ground dry matter, × increased to 1.62 g MJ -1 when calculated on a total dry matter basis (shoot + root + rhizome). Total dry matter production was increased 68% by a 2.2-fold increase in plant density. (author)

Effects of water and nutrient addition on the coppice growth response of cut Terminalia sericea

Directory of Open Access Journals (Sweden)

Hloniphani Moyo

2016-07-01

Full Text Available The ability of a woody plant to coppice and remain vigorous largely depends on the severity of disturbances, resource availability and the mobilisation of stored reserves. There is limited information about the role played by resource limitation on the recovery of cut trees. This study investigated the effects of water and nutrient supplementation on coppice growth responses of resprouting cut trees in a semi-arid savannah in South Africa. Cut trees were exposed to different levels of water and nutrient (nitrogen and phosphorus supplementation over a period of 2 years in a factorial experimental design. We hypothesised that adding water and nutrients would result in an increased coppice growth response and replenishment of stored structural reserves. Adding water and nutrients significantly increased shoot diameter, shoot length and resprouting ratio for the initial 12 months after cutting but not stored structural reserves. Such a response pattern suggests that the initial growth of resprouting shoots may be strongly resource-limited, while resources are concentrated on supporting fewer resprouting shoots compared to a higher number. Conservation implications: If practicing rotational tree harvesting, trees resprouting in resource-poor locations need a longer resting period to recover stored reserves and to also recover lost height after cutting.

Alginate-encapsulation of shoot tips of jojoba [Simmondsia chinensis (Link) Schneider] for germplasm exchange and distribution.

Science.gov (United States)

Kumar, Sunil; Rai, Manoj K; Singh, Narender; Mangal, Manisha

2010-12-01

Shoot tips excised from in vitro proliferated shoots derived from nodal explants of jojoba [Simmondsia chinensis (Link) Schneider] were encapsulated in calcium alginate beads for germplasm exchange and distribution. A gelling matrix of 3 % sodium alginate and 100 mM calcium chloride was found most suitable for formation of ideal calcium alginate beads. Best response for shoot sprouting from encapsulated shoot tips was recorded on 0.8 % agar-solidified full-strength MS medium. Rooting was induced upon transfer of sprouted shoots to 0.8 % agar-solidified MS medium containing 1 mg l(-1) IBA. About 70 % of encapsulated shoot tips were rooted and converted into plantlets. Plants regenerated from encapsulated shoot tips were acclimatized successfully. The present encapsulation approach could also be applied as an alternative method of propagation of desirable elite genotype of jojoba.

Lead Pollution of Shooting Range Soils

African Journals Online (AJOL)

NICOLAAS

range. Most of the shooting range soils contained high levels of Pb in the range above 2000 mg kg–1 far exceeding the United States ... N. Sehube, R. Kelebemang, O. Totolo, M. Laetsang, O. Kamwi and P. Dinake,. 21 ..... Eng. Sci., 1999, 16,.

Psychological Outcomes in Asian and Asian American Survivors of the April 16th Shooting at Virginia Tech: Roles of Acculturation and Parental Overprotection

OpenAIRE

Amatya, Kaushalendra

2011-01-01

The negative impacts of mass shootings on mental health have been documented within the general trauma literature. Substantial research has also shown the Asian population to be a minority group especially vulnerable to negative psychological outcomes following trauma and stress. Acculturation has been studied extensively as a predictor of psychological outcomes in several minority groups. Furthermore, parental overprotection has also been found to have a negative impact on mental health. ...

Induction of shoot regeneration in cotyledon explants of the oilseed crop Sesamum indicum L.

Directory of Open Access Journals (Sweden)

Masochon Zimik

2017-12-01

Full Text Available Sesamum indicum is an ancient oilseed crop known for its high quality edible oil and its medicinally important lignans. The crop is said to be recalcitrant to plant tissue culture thus limiting the use of modern biotechnology for its genetic improvement. We present here a protocol describing plant regeneration through adventitious shoot formation from cotyledons dissected from sesame seeds soaked for four hours in water. Subculturing of the cotyledons after two weeks of culture on to a fresh Murashige and Skoog medium leads to differentiation of adventitious shoots from the proximal cut end of the explant. Culture of cotyledons on a medium containing 9% sucrose for a couple of weeks prior to transfer to MS medium supplemented with 3% sucrose induced a higher frequency of shoot regeneration. The highest frequency of 25% adventitious shoot regeneration was observed for S. indicum variety UMA. This variety also turned out to be the best among the ten genotypes tested for shoot regeneration through tissue culture. While addition of IAA marginally improved regeneration, silver nitrate was found essential for enhancing the frequency of shoot regeneration. The regenerated shoots formed roots on full strength MS medium supplemented with 1 mg/l IBA and the rooted plants were established in soil.

Effects of fish farm loadings on seagrass (Posidonia oceanica) distribution, growth and photosynthesis.

Science.gov (United States)

Ruiz, J M; Pérez, M; Romero, J

2001-09-01

The spatial extent and timing of the impact of fish farms on the distribution and performance of a Posidonia oceanica meadow were examined in an embayment of the south-eastern coast of Spain (Hornillo Bay, Murcia). Changes in seagrass distribution were determined using available seagrass mapping (from 1988, i.e., before the onset of aquaculture activities and 1998) and by successive sampling in 1994 and 1998. Environmental variables (light attenuation coefficient, water-column dissolved nutrients and organic content of sediments) together with plant performance (shoot biomass, leaf growth rate, photosynthetic activity, carbohydrate reserves, the number of leaves per shoot, epiphyte loads and herbivore pressure) were measured in plants affected by organic discharges, and were compared with those found in reference healthy plants over an annual growth cycle. Since the onset of fish farm activity, 11.29 ha of P. oceanica meadow has been completely lost and 9.86 ha significantly degraded, thus resulting in a total affected area which accounts for about 53% of the former meadow, or 7-fold the fish farming area. Unequal propagation of seagrass die-off or degradation reflects the relevance of local factors such as depth and hydrodynamism on the true extent of fish farm impact. Water transparency decreases and dissolved nutrient and organic content of sediments increases in the vicinity of cages compared to distant reference stations, thus supporting the notion of environmental gradients caused by the organic release from cages, which spreads outwards. Shoot size, leaf growth rate and the number of leaves per shoot in plants close to the fish farm decreased. Moreover, low leaf growth and low rhizome carbohydrate concentration (always relative to that found in an undisturbed area) indicated carbon budget imbalances. Since light reduction in the affected area was only modest (31% of light reaching the sea surface, while at the same depth this figure was 39% at the reference

Coumarins and alkaloids in shoot culture of Ruta graveolens L.

Directory of Open Access Journals (Sweden)

Halina Ekiert

2014-01-01

Full Text Available A shoot culture of Ruta graveolens L. (Rutaceae was maintained in the stationary liquid phase. From the cultured shoots seven compounds were isolated and identified as psoralen, bergapten, xanthotoxin, isopimpinellin (linear furanocoumarins, rutamarin (linear dihydrofuranocoumarin, kokusaginine and skimmianine (furanoquinoline alkaloids by spectral methods. The compounds are known as secondary metabolites of the intact plant, as well as its cell and tissue cultures.

Long-term impact of shoot blight disease on red pine saplings

Science.gov (United States)

Linda M. Haugen; Michael E. Ostry

2013-01-01

Damage from Sirococcus and Diplodia shoot blights of red pine is widespread and periodically severe in the Lake States. An outbreak of shoot blight occurred in red pine sapling plantations across northern Wisconsin, northern Minnesota, and the Upper Peninsula of Michigan in 1993. We established monitoring plots in red pine sapling...

The effect of plant growth regulators, explants and cultivars on ...

African Journals Online (AJOL)

To achieve the best explants and media for spinach tissue culture, the effects of two different plant growth regulators, two explants and cultivars on adventitious shoot regeneration were tested. The Analysis of Variance (ANOVA) showed that the effects of plant growth regulators on spinach tissue culture were significant; ...

Bioconcentration of atrazine and chlorophenols into roots and shoots of rice seedlings

International Nuclear Information System (INIS)

Su Yuhong; Zhu Yongguan

2006-01-01

Accumulation of o-chlorophenol (CP), 2,4-dichlorophenol (DCP), and atrazine (ATR), as single and mixed contaminants, from hydroponic solutions into roots and shoots of rice seedlings was studied following 48-h exposure of the plant roots. As single contaminants at low levels, the observed bioconcentration factors (BCFs) of CP and DCP with roots approximated the equilibrium values according to the partition-limited model. The BCF of atrazine with roots was about half the partition limit for unknown reasons. The BCFs of CP and ATR with shoots also approximated the partition limits, while the BCF for more lipophilic DCP with shoots was about half the estimated limit, due to insufficient water transport into plants for DCP. As mixed contaminants at low levels, the BCFs with both roots and shoots were comparable with those for the single contaminants; at high levels, the BCFs generally decreased because of the enhanced mixed-contaminant phytotoxicity, as manifested by the greatly reduced plant transpiration rate. - Uptakes of o-chlorophenol, 2,4-dichlorophenol, and atrazine at various levels from nutrient solution by roots and shoots of rice seedlings were investigated using a partition-limited model

Empirical models in the description of prickly pear shoot (Nopal drying kinetics

Directory of Open Access Journals (Sweden)

Emmanuel M. Pereira

Full Text Available ABSTRACT The objective of this study was to describe the technological process involved in the drying kinetics of fresh-cut prickly pear shoots through numerical and analytical solutions. Shoots of two different prickly pear species were used, ‘Gigante’ and ‘Miúda’. Drying was performed at different temperatures (50, 60, 70 and 80 °C and weighing procedures were made continuously. The experimental data were expressed as moisture ratio. The Page model showed the best fit to the drying kinetics of minimally processed ‘Gigante’ and ‘Miúda’ prickly pear shoots, with the best coefficients of determination and Chi-square. Peleg and Wang & Singh models can not be used to simulate the drying of ‘Gigante’ and ‘Miúda’ prickly pear shoots within the evaluated range of temperatures, showing an incoherent graphic pattern.

Influence of Rhizophagus irregularis inoculation and phosphorus application on growth and arsenic accumulation in maize (Zea mays L.) cultivated on an arsenic-contaminated soil.

Science.gov (United States)

Cattani, I; Beone, G M; Gonnelli, C

2015-05-01

Southern Tuscany (Italy) is characterized by extensive arsenic (As) anomalies, with concentrations of up to 2000 mg kg soil(-1). Samples from the location of Scarlino, containing about 200 mg kg(-1) of As, were used to study the influence of the inoculation of an arbuscular mycorrhizal (AM) fungus (Rhizophagus irregularis, previously known as Glomus intraradices) and of phosphorus (P) application, separately and in combination, on As speciation in the rhizosphere of Zea mays on plant growth and As accumulation. Also, P distribution in plant parts was investigated. Each treatment produced a moderate rise of As(III) in the rhizosphere, increased As(III) and lowered As(V) concentration in shoots. P treatment, alone or in combination with AM, augmented the plant biomass. The treatments did not affect total As concentration in the shoots (with all the values <1 mg kg(-1) dry weight), while in the roots it was lowered by P treatment alone. Such decrease was probably a consequence of the competition between P and As(V) for the same transport systems, interestingly nullified by the combination with AM treatment. P concentration was higher with AM only in both shoots and roots. Therefore, the obtained results can be extremely encouraging for maize cultivation on a marginal land, like the one studied.

Effect of arbuscular mycorrhizal fungal inoculation on growth, and ...

African Journals Online (AJOL)

FAMA

2015-09-30

Sep 30, 2015 ... AMF on root colonization, biomass production, mycorrhizal dependency (MD) and shoot mineral ... four months of growth in a sterilized soil and greenhouse conditions, grasses inoculated with AMF ..... Quetta, Pakistan.

Experts Appear to Use Angle of Elevation Information in Basketball Shooting

Science.gov (United States)

de Oliveira, Rita Ferraz; Oudejans, Raoul R. D.; Beek, Peter J.

2009-01-01

For successful basketball shooting, players must use information about the location of the basket relative to themselves. In this study, the authors examined to what extent shooting performance depends on the absolute distance to the basket ("m") and the angle of elevation (alpha). In Experiment 1, expert players took jump shots under different…

Inheritance of Resistance to Sorghum Shoot Fly, Atherigona soccata in Sorghum, Sorghum bicolor (L. Moench

Directory of Open Access Journals (Sweden)

Mohammed eRiyazaddin

2016-04-01

Full Text Available Host plant resistance is one of the major components to control sorghum shoot fly, Atherigona soccata. To understand the nature of gene action for inheritance of shoot fly resistance, we evaluated 10 parents, 45 F1’s and their reciprocals in replicated trials during the rainy and postrainy seasons. Genotypes ICSV 700, Phule Anuradha, ICSV 25019, PS 35805, IS 2123, IS 2146 and IS 18551 exhibited resistance to shoot fly damage across seasons. Crosses between susceptible parents were preferred for egg laying by the shoot fly females, resulting in a susceptible reaction. ICSV 700, ICSV 25019, PS 35805, IS 2123, IS 2146 and IS 18551 exhibited significant and negative general combining ability (gca effects for oviposition, deadheart incidence, and overall resistance score. The plant morphological traits associated with expression of resistance/ susceptibility to shoot fly damage such as leaf glossiness, plant vigor, and leafsheath pigmentation also showed significant gca effects by these genotypes, suggesting the potential for use as a selection criterion to breed for resistance to shoot fly, A. soccata. ICSV 700, Phule Anuradha, IS 2146 and IS 18551 with significant positive gca effects for trichome density can also be utilised in improving sorghums for shoot fly resistance. The parents involved in hybrids with negative specific combining ability (sca effects for shoot fly resistance traits can be used in developing sorghum hybrids with adaptation to postrainy season. The significant reciprocal effects of combining abilities for oviposition, leaf glossy score and trichome density suggested the influence of cytoplasmic factors in inheritance of shoot fly resistance. Higher values of variance due to sca (σ2s, dominance variance (σ2d, and lower predictability ratios than the variance due to gca (σ2g and additive variance (σ2a for shoot fly resistance traits indicated the predominance of dominance type of gene action, whereas trichome density, leaf

The effect of mycorrhiza on the growth and elemental composition of Ni-hyperaccumulating plant Berkheya coddii Roessler

Energy Technology Data Exchange (ETDEWEB)

Orlowska, Elzbieta, E-mail: elo@mb.au.dk [Materials Research Department, iThemba LABS, PO Box 722, Somerset West 7129 (South Africa); Przybylowicz, Wojciech; Orlowski, Dariusz [Materials Research Department, iThemba LABS, PO Box 722, Somerset West 7129 (South Africa); Turnau, Katarzyna [Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Krakow (Poland); Mesjasz-Przybylowicz, Jolanta [Materials Research Department, iThemba LABS, PO Box 722, Somerset West 7129 (South Africa)

2011-12-15

The effect of arbuscular mycorrhizal fungi (AMF) on growth and element uptake by Ni-hyperaccumulating plant, Berkheya coddii, was studied. Plants were grown under laboratory conditions on ultramafic soil without or with the AM fungi of different origin. The AM colonization, especially with the indigenous strain, significantly enhanced plants growth and their survival. AMF affected also the elemental concentrations that were studied with Particle-induced X-ray emission (PIXE). AMF (i) increased K and Fe in shoots, Zn and Mn in roots, P and Ca both, in roots and shoots; (ii) decreased Mn in shoots, Co and Ni both, in shoots and roots. Due to higher biomass of mycorrhizal plants, total Ni content was up to 20 times higher in mycorrhizal plants compared to the non-mycorrhizal ones. The AMF enhancement of Ni uptake may therefore provide an improvement of a presently used technique of nickel phytomining. - Highlights: > The role of arbuscular mycorrhizal fungi in Ni-hyperaccumulating plant was studied. > Growth of Berkheya coddii was significantly enhanced by mycorrhizal inoculation. > Mycorrhizal symbiosis increased Ni uptake to aboveground part of the plants. > Mycorrhizal colonization affected concentration and uptake of other elements. > Arbuscular mycorrhizal fungi could improve the techniques of nickel phytomining. - Inoculation of Ni-hyperaccumulating plant Berkheya coddii with arbuscular mycorrhizal fungi significantly enhanced plant growth and increased Ni uptake.

The effect of mycorrhiza on the growth and elemental composition of Ni-hyperaccumulating plant Berkheya coddii Roessler

International Nuclear Information System (INIS)

Orlowska, Elzbieta; Przybylowicz, Wojciech; Orlowski, Dariusz; Turnau, Katarzyna; Mesjasz-Przybylowicz, Jolanta

2011-01-01

The effect of arbuscular mycorrhizal fungi (AMF) on growth and element uptake by Ni-hyperaccumulating plant, Berkheya coddii, was studied. Plants were grown under laboratory conditions on ultramafic soil without or with the AM fungi of different origin. The AM colonization, especially with the indigenous strain, significantly enhanced plants growth and their survival. AMF affected also the elemental concentrations that were studied with Particle-induced X-ray emission (PIXE). AMF (i) increased K and Fe in shoots, Zn and Mn in roots, P and Ca both, in roots and shoots; (ii) decreased Mn in shoots, Co and Ni both, in shoots and roots. Due to higher biomass of mycorrhizal plants, total Ni content was up to 20 times higher in mycorrhizal plants compared to the non-mycorrhizal ones. The AMF enhancement of Ni uptake may therefore provide an improvement of a presently used technique of nickel phytomining. - Highlights: → The role of arbuscular mycorrhizal fungi in Ni-hyperaccumulating plant was studied. → Growth of Berkheya coddii was significantly enhanced by mycorrhizal inoculation. → Mycorrhizal symbiosis increased Ni uptake to aboveground part of the plants. → Mycorrhizal colonization affected concentration and uptake of other elements. → Arbuscular mycorrhizal fungi could improve the techniques of nickel phytomining. - Inoculation of Ni-hyperaccumulating plant Berkheya coddii with arbuscular mycorrhizal fungi significantly enhanced plant growth and increased Ni uptake.

Effect of zinc oxide (ZnO) nanoparticles on physiology and steviol glycosides production in micropropagated shoots of Stevia rebaudiana Bertoni.

Science.gov (United States)

Javed, Rabia; Usman, Muhammad; Yücesan, Buhara; Zia, Muhammad; Gürel, Ekrem

2017-01-01

This study aims to address the effects of different concentrations (0, 0.1, 1.0, 10, 100 or 1000 mg L -1 ) of engineered zinc oxide (ZnO) nanoparticles (34 nm in size) on growth parameters, steviol glycosides (rebaudioside A and stevioside) production and antioxidant activities in the tissue culture grown shoots of Stevia rebaudiana Bertoni. The highest percentage of shoot formation (89.6%) at 1 mg L -1 of ZnO nanoparticles concentration suggests a positive influence of ZnO nanoparticles on S. rebaudiana growth as compared to other treatments with or without ZnO nanoparticles. Additionally, HPLC results illustrate a significant enhancement of steviol glycosides (almost doubled as compared to the control) in micropropagated shoots grown under an oxidative stress of 1 mg L -1 of ZnO nanoparticles. This finding is further affirmed by an increased 2,2-diphenyl-1-picryl hydrazyl (DPPH) scavenging activity, total anti-oxidant capacity, total reducing power, total flavonoid content and total phenolic content, with an ascending oxidative pressure and generation of reactive oxygen species (ROS). However, the antioxidant activities, formation of secondary metabolites and the physiological parameters showed a sudden decline after crossing a threshold of 1 mg L -1 concentration of ZnO nanoparticles and falls to a minimum at 1000 mg L -1 , elucidating maximum phytotoxic effect of ZnO nanoparticles at this concentration. This is the first study evaluating both the favorable and adverse effects of ZnO nanoparticles employed to a highly valuable medicinal plant, S. rebaudiana. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

performance routines followed by free throw shooting accuracy in secondary basketball players

Directory of Open Access Journals (Sweden)

Phelps Ashley

2015-12-01

Full Text Available Study aim: The purpose of the current study was to determine whether existing pre-performance routines had an effect on free throw shooting accuracy in high school pupils as compared to shooting without a pre-performance routine.

Shootings Revive Debates on Security

Science.gov (United States)

Shah, Nirvi

2013-01-01

By nearly all accounts, the staff and students at Sandy Hook Elementary School did everything right on Dec. 14--and with the security measures they took before that day--when a young man armed with powerful weapons blasted his way into the school. But the deadliest K-12 school shooting in American history, a day that President Barack Obama has…

Energetic exploitation of vine shoot by gasification processes

Energy Technology Data Exchange (ETDEWEB)

Ganan, J.; Al-Kassir Abdulla, A. [Dpto. Ingenieria Quimica y Energetica, Escuela de Ingenierias Industriales, Universidad de Extremadura, Avda de Elvas s/n, E-06071 Badajoz (Spain); Cuerda Correa, E.M. [Dpto. Quimica Inorganica, Facultad de Ciencias, Universidad de Extremadura, Avda de Elvas s/n, E-06071 Badajoz (Spain); Macias-Garcia, A. [Dpto. Electronica e Ingenieria Electromecanica, Escuela de Ingenierias Industriales, Universidad de Extremadura, Avda de Elvas s/n, E-06071 Badajoz (Spain)

2006-10-15

In this study the energy potential generated by the biomass remnants of vine shoot produced in Extremadura (Spain) by a gasification process is evaluated. The raw material was characterised by elemental and proximate analysis, its Higher Heating Value (HHV) being evaluated as well. In order to determine the optimal gasification temperature for the production of gases, the vine shoots were treated at different temperatures, i.e., 650, 700, 750 and 800 {sup o}C in air atmosphere. The optimal temperature (800 {sup o}C) was selected and the vine shoot remnants were gasified in air stream (200 mL min{sup -1}) and for different times (8 and 50 min). The yield of the so-obtained phases was calculated and the study was focused on solid and gaseous phases. The solid phase was characterised by elemental and proximate analysis as well as by HHV. In order to determine their properties as precursors of activated carbons, the adsorption isotherms of N{sub 2} at 77 K were measured. Finally, the electric power that could be obtained by a combustion process in a vapor boiler was calculated. (author)

Effects of lead and chelators on growth, photosynthetic activity and Pb uptake in Sesbania drummondii grown in soil

International Nuclear Information System (INIS)

Ruley, Adam T.; Sharma, Nilesh C.; Sahi, Shivendra V.; Singh, Shree R.; Sajwan, Kenneth S.

2006-01-01

Effects of lead (Pb) and chelators, such as EDTA, HEDTA, DTPA, NTA and citric acid, were studied to evaluate the growth potential of Sesbania drummondii in soils contaminated with high concentrations of Pb. S. drummondii seedlings were grown in soil containing 7.5 g Pb(NO 3 ) 2 and 0-10 mmol chelators/kg soil for a period of 2 and 4 weeks and assessed for growth profile (length of root and shoot), chlorophyll a fluorescence kinetics (F v /F m and F v /F o ) and Pb accumulations in root and shoot. Growth of plants in the presence of Pb + chelators was significantly higher (P v /F m and F v /F o values of treated seedlings remained unaffected, indicating normal photosynthetic efficiency and strength of plants in the presence of chelators. On application of chelators, while root uptake of Pb increased four-five folds, shoot accumulations increased up to 40-folds as compared to controls (Pb only) depending on the type of chelator used. Shoot accumulations of Pb varied from 0.1 to 0.42% (dry weight) depending on the concentration of chelators used. - Sesbania drummondii tolerates and accumulates high concentrations of Pb

Influence of variety and type of shoot on rooting ability of green stem cuttings of highbush blueberry (Vaccinium corymbosum L.

Directory of Open Access Journals (Sweden)

А. А. Пиж’янова

2013-05-01

Full Text Available The article provides results of studying the output percentage of green stem cuttings of seven varieties of Highbush blueberry (Vaccinium corymbosum L. subject to the dates of cutting preparation, type of shoot and its metamerism in agroecological conditions of the Rightbank Forest Steppe of Ukraine. It is found that green stem cuttings of Highbush blueberry varieties under review display low regenerative ability and are characterized with medium rooting ability. The optimal procuring and planting for rooting dates for the shoots fall within the stage of their intensive growth, which lasts from the first decade of June till the second decade of July. The level of regenerative capacity for the cuttings is determined by the type of cutting and its metamerism. Basal three-node cuttings have displayed essentially improved rooting ability as compared to the apical and medial cuttings.

Shooting method for solution of boundary-layer flows with massive blowing

Science.gov (United States)

Liu, T.-M.; Nachtsheim, P. R.

1973-01-01

A modified, bidirectional shooting method is presented for solving boundary-layer equations under conditions of massive blowing. Unlike the conventional shooting method, which is unstable when the blowing rate increases, the proposed method avoids the unstable direction and is capable of solving complex boundary-layer problems involving mass and energy balance on the surface.

Mangrove endophyte promotes reforestation tree (Acacia polyphylla growth

Directory of Open Access Journals (Sweden)

Renata Assis Castro

Full Text Available ABSTRACT Mangroves are ecosystems located in the transition zone between land and sea that serve as a potential source of biotechnological resources. Brazil's extensive coast contains one of the largest mangrove forests in the world (encompassing an area of 25,000 km2 along all the coast. Endophytic bacteria were isolated from the following three plant species: Rhizophora mangle, Laguncularia racemosa and Avicennia nitida. A large number of these isolates, 115 in total, were evaluated for their ability to fix nitrogen and solubilize phosphorous. Bacteria that tested positive for both of these tests were examined further to determine their level of indole acetic acid production. Two strains with high indole acetic acid production were selected for use as inoculants for reforestation trees, and then the growth of the plants was evaluated under field conditions. The bacterium Pseudomonas fluorescens (strain MCR1.10 had a low phosphorus solubilization index, while this index was higher in the other strain used, Enterobacter sp. (strain MCR1.48. We used the reforestation tree Acacia polyphylla. The results indicate that inoculation with the MCR1.48 endophyte increases Acacia polyphylla shoot dry mass, demonstrating that this strain effectively promotes the plant's growth and fitness, which can be used in the seedling production of this tree. Therefore, we successfully screened the biotechnological potential of endophyte isolates from mangrove, with a focus on plant growth promotion, and selected a strain able to provide limited nutrients and hormones for in plant growth.

Gum in apricot (Prunus armeniaca L. shoots induced by methyl jasmonate

Directory of Open Access Journals (Sweden)

Marian Saniewski

2013-12-01

Full Text Available It has been well known that some fungal pathogens (Monilia laxa, M. fructigena, Cytospora cincta, larvae of Grapholita molesta and plant hormone - ethylene, induce gummosis in apricot shoots. Methyl jasmonate (JA-Me was also found to induce gummosis in apricot shoots as well as biotic and abiotic factors mentioned above. In order to know the mode of action of JA-Me on gum induction and/or formation, chemical composition of polysaccharides (after hydrolysis in gums of apricot shoots induced by JA-Me compared with those by ethephon and their mixture, and naturally occurring ones was studied, resulted in the succesful identification of monosaccharides, and the similarity of a composition consisting of xylose, arabinose and galactose at molar ratio 1:10:14, respectively. These results suggest that beside different inducers of gum in apricot the mechanism of polysaccharides biosynthesis of gums is the same or similar. The physiological role for JA-Me on gum induction and/or formation in apricot shoots, and other species are also discussed.

Accurate inference of shoot biomass from high-throughput images of cereal plants

Directory of Open Access Journals (Sweden)

Tester Mark

2011-02-01

Full Text Available Abstract With the establishment of advanced technology facilities for high throughput plant phenotyping, the problem of estimating plant biomass of individual plants from their two dimensional images is becoming increasingly important. The approach predominantly cited in literature is to estimate the biomass of a plant as a linear function of the projected shoot area of plants in the images. However, the estimation error from this model, which is solely a function of projected shoot area, is large, prohibiting accurate estimation of the biomass of plants, particularly for the salt-stressed plants. In this paper, we propose a method based on plant specific weight for improving the accuracy of the linear model and reducing the estimation bias (the difference between actual shoot dry weight and the value of the shoot dry weight estimated with a predictive model. For the proposed method in this study, we modeled the plant shoot dry weight as a function of plant area and plant age. The data used for developing our model and comparing the results with the linear model were collected from a completely randomized block design experiment. A total of 320 plants from two bread wheat varieties were grown in a supported hydroponics system in a greenhouse. The plants were exposed to two levels of hydroponic salt treatments (NaCl at 0 and 100 mM for 6 weeks. Five harvests were carried out. Each time 64 randomly selected plants were imaged and then harvested to measure the shoot fresh weight and shoot dry weight. The results of statistical analysis showed that with our proposed method, most of the observed variance can be explained, and moreover only a small difference between actual and estimated shoot dry weight was obtained. The low estimation bias indicates that our proposed method can be used to estimate biomass of individual plants regardless of what variety the plant is and what salt treatment has been applied. We validated this model on an independent

The influence of sward competition on shoot growth and ...

African Journals Online (AJOL)

In each of two seasons the growth form of Senecio retrorsus plants in Natal Tall Grassveld differed in accordance with the degree of utilization of the grasses and thus the degree of competition offered. In rested veld the main stems of seedlings and mature plants were long and spindly while those in frequently clipped veld ...

Training, Drills Pivotal in Mounting Response to Orlando Shooting.

Science.gov (United States)

Albert, Eric; Bullard, Timothy

2016-08-01

Emergency providers at Orlando Regional Medical Center in Orlando. FL, faced multiple challenges in responding to the worst mass shooting in U.S. history. As the scene of the shooting was only three blocks away from the hospital, there was little time to prepare when notified that victims would begin arriving shortly after 2 a.m. on June 12. Also, fears of a gunman near the hospital briefly put the ED on lock down. However, using the incident command system, the hospital was able to mobilize quickly, receiving 44 patients, nine of whom died shortly after arrival. Administrators note that recent training exercises geared toward a mass shooting event facilitated the response and probably saved lives. Patients arrived at the hospital in two waves, with the initial surge occurring right after the hooting took place around 2 a.m., and the second surge occurring about three hours later. At one point, more than 90 patients were in the ED, more than half for reasons unrelated to the shooting. Clinicians contended with a much higher than usual noise level while treating patients, making it hard to hear reports from EMS personnel. Also, treatment had to commence prior to identification for some patients who arrived unconscious or unable to speak. While surgeons and other key specialists were called into the hospital to address identified needs, administrators actually called hospital personnel to tell them not to come in unless they were notified. This prevented added management hurdles.

Characterization of somatic embryogenesis initiated from the Arabidopsis shoot apex.

Science.gov (United States)

Kadokura, Satoshi; Sugimoto, Kaoru; Tarr, Paul; Suzuki, Takamasa; Matsunaga, Sachihiro

2018-04-28

Somatic embryogenesis is one of the best examples of the remarkable developmental plasticity of plants, in which committed somatic cells can dedifferentiate and acquire the ability to form an embryo and regenerate an entire plant. In Arabidopsis thaliana, the shoot apices of young seedlings have been reported as an alternative tissue source for somatic embryos (SEs) besides the widely studied zygotic embryos taken from siliques. Although SE induction from shoots demonstrates the plasticity of plants more clearly than the embryo-to-embryo induction system, the underlying developmental and molecular mechanisms involved are unknown. Here we characterized SE formation from shoot apex explants by establishing a system for time-lapse observation of explants during SE induction. We also established a method to distinguish SE-forming and non-SE-forming explants prior to anatomical SE formation, enabling us to identify distinct transcriptome profiles of these two explants at SE initiation. We show that embryonic fate commitment takes place at day 3 of SE induction and the SE arises directly, not through callus formation, from the base of leaf primordia just beside the shoot apical meristem (SAM), where auxin accumulates and shoot-root polarity is formed. The expression domain of a couple of key developmental genes for the SAM transiently expands at this stage. Our data demonstrate that SE-forming and non-SE-forming explants share mostly the same transcripts except for a limited number of embryonic genes and root genes that might trigger the SE-initiation program. Thus, SE-forming explants possess a mixed identity (SAM, root and embryo) at the time of SE specification. Copyright © 2018. Published by Elsevier Inc.

Regeneration efficiency based on genotype, culture condition and growth regulators of eggplant (Solanum melongena L.

Directory of Open Access Journals (Sweden)

Md Abdul Muktadir

2016-01-01

Full Text Available Several experiments were carried out to establish an efficient regenerating protocol for cultivated eggplant varieties. Among the five varieties cultured on Murashige and Skoog (MS medium with free plant growth regulator (PGR, Nayantara performed better considering the number of shoots/explant (2.48. Considering explant types and culture conditions, better performance was observed (3.68 shoots/explant when seed germination in the dark was proceeded by bottom hypocotyl segments cultured under dark conditions. A higher rate of shoot regeneration was observed in Nayantara when cultured in Zeatin Riboside (ZR and Thidizuron (TDZ supplemented MS medium. The highest number of shoots per explant was produced on MS medium supplemented with 2.0 mg/L ZR and 0.1 mg/L indole acetic acid (6.65 shoots/explant. Proliferation and elongation of the regenerated shoots were obtained in the MS medium with free PGR. The best rooting performance was observed in MS medium supplemented with 2.0 mg/L indole butyric acid. Plantlets with well developed roots and shoots were successfully transferred to soil.

Branch age and light conditions determine leaf-area-specific conductivity in current shoots of Scots pine.

Science.gov (United States)

Grönlund, Leila; Hölttä, Teemu; Mäkelä, Annikki

2016-08-01

Shoot size and other shoot properties more or less follow the availability of light, but there is also evidence that the topological position in a tree crown has an influence on shoot development. Whether the hydraulic properties of new shoots are more regulated by the light or the position affects the shoot acclimation to changing light conditions and thereby to changing evaporative demand. We investigated the leaf-area-specific conductivity (and its components sapwood-specific conductivity and Huber value) of the current-year shoots of Scots pine (Pinus sylvestris L.) in relation to light environment and topological position in three different tree classes. The light environment was quantified in terms of simulated transpiration and the topological position was quantified by parent branch age. Sample shoot measurements included length, basal and tip diameter, hydraulic conductivity of the shoot, tracheid area and density, and specific leaf area. In our results, the leaf-area-specific conductivity of new shoots declined with parent branch age and increased with simulated transpiration rate of the shoot. The relation to transpiration demand seemed more decisive, since it gave higher R(2) values than branch age and explained the differences between the tree classes. The trend of leaf-area-specific conductivity with simulated transpiration was closely related to Huber value, whereas the trend of leaf-area-specific conductivity with parent branch age was related to a similar trend in sapwood-specific conductivity. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Shoot-supplied ammonium targets the root auxin influx carrier AUX1 and inhibits lateral root emergence in Arabidopsis

KAUST Repository

Li, Baohai

2011-03-24

Deposition of ammonium (NH4 +) from the atmosphere is a substantial environmental problem. While toxicity resulting from root exposure to NH4 + is well studied, little is known about how shoot-supplied ammonium (SSA) affects root growth. In this study, we show that SSA significantly affects lateral root (LR) development. We show that SSA inhibits lateral root primordium (LRP) emergence, but not LRP initiation, resulting in significantly impaired LR number. We show that the inhibition is independent of abscisic acid (ABA) signalling and sucrose uptake in shoots but relates to the auxin response in roots. Expression analyses of an auxin-responsive reporter, DR5:GUS, and direct assays of auxin transport demonstrated that SSA inhibits root acropetal (rootward) auxin transport while not affecting basipetal (shootward) transport or auxin sensitivity of root cells. Mutant analyses indicated that the auxin influx carrier AUX1, but not the auxin efflux carriers PIN-FORMED (PIN)1 or PIN2, is required for this inhibition of LRP emergence and the observed auxin response. We found that AUX1 expression was modulated by SSA in vascular tissues rather than LR cap cells in roots. Taken together, our results suggest that SSA inhibits LRP emergence in Arabidopsis by interfering with AUX1-dependent auxin transport from shoot to root. © 2011 Blackwell Publishing Ltd.

Pre-hospital management of mass casualty civilian shootings: a systematic literature review.

Science.gov (United States)

Turner, Conor D A; Lockey, David J; Rehn, Marius

2016-11-08

Mass casualty civilian shootings present an uncommon but recurring challenge to emergency services around the world and produce unique management demands. On the background of a rising threat of transnational terrorism worldwide, emergency response strategies are of critical importance. This study aims to systematically identify, describe and appraise the quality of indexed and non-indexed literature on the pre-hospital management of modern civilian mass shootings to guide future practice. Systematic literature searches of PubMed, Cochrane Database of Systematic Reviews and Scopus were conducted in conjunction with simple searches of non-indexed databases; Web of Science, OpenDOAR and Evidence Search. The searches were last carried out on 20 April 2016 and only identified those papers published after the 1 January 1980. Included documents had to contain descriptions, discussions or experiences of the pre-hospital management of civilian mass shootings. From the 494 identified manuscripts, 73 were selected on abstract and title and after full text reading 47 were selected for inclusion in analysis. The search yielded reports of 17 mass shooting events, the majority from the USA with additions from France, Norway, the UK and Kenya. Between 1994 and 2015 the shooting of 1649 people with 578 deaths at 17 separate events are described. Quality appraisal demonstrated considerable heterogeneity in reporting and revealed limited data on mass shootings globally. Key themes were identified to improve future practice: tactical emergency medical support may harmonise inner cordon interventions, a need for inter-service education on effective haemorrhage control, the value of senior triage operators and the need for regular mass casualty incident simulation.

Studies on the tissue culture of Stevia rebaudiana and its components; (II). Induction of shoot primordia.

Science.gov (United States)

Miyagawa, H; Fujioka, N; Kohda, H; Yamasaki, K; Taniguchi, K; Tanaka, R

1986-08-01

Shoot primordia, which were able to propagate vegetatively with a very high rate and to redifferentiate easily to new plants, were induced from shoot tips of Stevia rebaudiana Bertoni on Gamborg B5 medium containing 6-benzylaminopurine (BAP) and alpha-naphthaleneacetic acid (NAA) under light. The propagation of the shoot primordia of Stevia rebaudiana is rapid, and they are highly stable in chromosome number and karyotype. The shoot primordia can propagate at a high rate for a long time without differentiation. At any time, the shoot primordia readily developed into plantlets with shoots and roots within 2 or 3 weeks in static culture on B5 medium containing 0.02 mg/l BAP and 2% sucrose. The plantlets were transplanted to sterilized soil to grow to normal adult plants.

Plant cell wall extensibility: connecting plant cell growth with cell wall structure, mechanics, and the action of wall-modifying enzymes

Energy Technology Data Exchange (ETDEWEB)

Cosgrove, Daniel J.

2015-11-25

The advent of user-friendly instruments for measuring force/deflection curves of plant surfaces at high spatial resolution has resulted in a recent outpouring of reports of the ‘Young's modulus’ of plant cell walls. The stimulus for these mechanical measurements comes from biomechanical models of morphogenesis of meristems and other tissues, as well as single cells, in which cell wall stress feeds back to regulate microtubule organization, auxin transport, cellulose deposition, and future growth directionality. In this article I review the differences between elastic modulus and wall extensibility in the context of cell growth. Some of the inherent complexities, assumptions, and potential pitfalls in the interpretation of indentation force/deflection curves are discussed. Reported values of elastic moduli from surface indentation measurements appear to be 10- to >1000-fold smaller than realistic tensile elastic moduli in the plane of plant cell walls. Potential reasons for this disparity are discussed, but further work is needed to make sense of the huge range in reported values. The significance of wall stress relaxation for growth is reviewed and connected to recent advances and remaining enigmas in our concepts of how cellulose, hemicellulose, and pectins are assembled to make an extensible cell wall. A comparison of the loosening action of α-expansin and Cel12A endoglucanase is used to illustrate two different ways in which cell walls may be made more extensible and the divergent effects on wall mechanics.

Reality-based practice under pressure improves handgun shooting performance of police officers.

NARCIS (Netherlands)

Oudejans, R.R.D.

2008-01-01

The current study examined whether reality-based practice under pressure may help in preventing degradation of handgun shooting performance under pressure for police officers. Using a pre-post-test design, one group of nine police officers practised handgun shooting under pressure evoked by an

The FANTASTIC FOUR proteins influence shoot meristem size in Arabidopsis thaliana

Directory of Open Access Journals (Sweden)

Brand Luise H

2010-12-01

Full Text Available Abstract Background Throughout their lives plants produce new organs from groups of pluripotent cells called meristems, located at the tips of the shoot and the root. The size of the shoot meristem is tightly controlled by a feedback loop, which involves the homeodomain transcription factor WUSCHEL (WUS and the CLAVATA (CLV proteins. This regulatory circuit is further fine-tuned by morphogenic signals such as hormones and sugars. Results Here we show that a family of four plant-specific proteins, encoded by the FANTASTIC FOUR (FAF genes, has the potential to regulate shoot meristem size in Arabidopsis thaliana. FAF2 and FAF4 are expressed in the centre of the shoot meristem, overlapping with the site of WUS expression. Consistent with a regulatory interaction between the FAF gene family and WUS, our experiments indicate that the FAFs can repress WUS, which ultimately leads to an arrest of meristem activity in FAF overexpressing lines. The finding that meristematic expression of FAF2 and FAF4 is under negative control by CLV3 further supports the hypothesis that the FAFs are modulators of the genetic circuit that regulates the meristem. Conclusion This study reports the initial characterization of the Arabidopsis thaliana FAF gene family. Our data indicate that the FAF genes form a plant specific gene family, the members of which have the potential to regulate the size of the shoot meristem by modulating the CLV3-WUS feedback loop.

The FANTASTIC FOUR proteins influence shoot meristem size in Arabidopsis thaliana.

Science.gov (United States)

Wahl, Vanessa; Brand, Luise H; Guo, Ya-Long; Schmid, Markus

2010-12-22

Throughout their lives plants produce new organs from groups of pluripotent cells called meristems, located at the tips of the shoot and the root. The size of the shoot meristem is tightly controlled by a feedback loop, which involves the homeodomain transcription factor WUSCHEL (WUS) and the CLAVATA (CLV) proteins. This regulatory circuit is further fine-tuned by morphogenic signals such as hormones and sugars. Here we show that a family of four plant-specific proteins, encoded by the FANTASTIC FOUR (FAF) genes, has the potential to regulate shoot meristem size in Arabidopsis thaliana. FAF2 and FAF4 are expressed in the centre of the shoot meristem, overlapping with the site of WUS expression. Consistent with a regulatory interaction between the FAF gene family and WUS, our experiments indicate that the FAFs can repress WUS, which ultimately leads to an arrest of meristem activity in FAF overexpressing lines. The finding that meristematic expression of FAF2 and FAF4 is under negative control by CLV3 further supports the hypothesis that the FAFs are modulators of the genetic circuit that regulates the meristem. This study reports the initial characterization of the Arabidopsis thaliana FAF gene family. Our data indicate that the FAF genes form a plant specific gene family, the members of which have the potential to regulate the size of the shoot meristem by modulating the CLV3-WUS feedback loop.

Factors influencing flower bud formation on the pear tree cultivar 'Doyenne du Cornice'. II. Influence of growth inhibition on the anatomical structure of the stem

Directory of Open Access Journals (Sweden)

Franciszka Jaumień

2013-12-01

Full Text Available Differentiation of the particular tissues in shoots inhibited in growth by chlormequat occurs differently than in vigorously growing ones. After the end of elongation growth, in the subapical part of shoots sprayed with chlormequat the cortex extends and secondary xylem develops less intensively, this leading to an increased participation of parenchymatous tissue in the stem.

Adaptive L1/2 Shooting Regularization Method for Survival Analysis Using Gene Expression Data

Directory of Open Access Journals (Sweden)

Xiao-Ying Liu

2013-01-01

Full Text Available A new adaptive L1/2 shooting regularization method for variable selection based on the Cox’s proportional hazards mode being proposed. This adaptive L1/2 shooting algorithm can be easily obtained by the optimization of a reweighed iterative series of L1 penalties and a shooting strategy of L1/2 penalty. Simulation results based on high dimensional artificial data show that the adaptive L1/2 shooting regularization method can be more accurate for variable selection than Lasso and adaptive Lasso methods. The results from real gene expression dataset (DLBCL also indicate that the L1/2 regularization method performs competitively.

Framing Mass Shootings: Fictional Depictions of Real-life Gun Massacres in American Cinema

OpenAIRE

Tryggeseid, Ane Johannessen

2017-01-01

This thesis examines the concept of real-life mass shootings and its depiction in American fictional cinema. The issue of mass shootings is a highly controversial subject of discussion, both within the public and political sphere, as it necessarily touches upon rigid perceptions of civil liberties – specifically those of the Second Amendment – which further permeates the field of fictional cinema. As opposed to assessing the issue of mass shootings as a product of a prevailing culture of guns...

Effect of Water Deficit Stress on Peach Growth under Commercial Orchard Management Conditions

Directory of Open Access Journals (Sweden)

M. Rahmati

2015-06-01

Full Text Available In order to study the sensitivity of vegetative growth to water deficit stress of a late-maturing peach (Prunus persica L. cv. Elberta under orchard conditions, an experiment was conducted as randomized complete-block design with three treatments and four repetitions in Shahdiran commercial orchard in Mashhad during 2011. Three irrigation treatments including 360 (low stress, 180 (moderate stress and 90 (severe stress m3ha-1week-1 using a drip irrigation system (minimum stem water potential near harvest: -1.2, -1.5 and -1.7 MPa, respectively from the mid-pit hardening stage (12th of June until harvest (23rd of Sep. applied. Predawn, stem and leaf water potentials, leaf photosynthesis, transpiration, stomatal conductance and leaf temperature, the number of new shoots on fruit bearing shoots and vegetative shoots lengths during growing season as well as leaf area at harvest were measured. The results showed that water deficit stress had negative effects on peach tree water status, thereby resulting in decreased leaf gas exchange and tree vegetative growth. As significant decreased assimilate production of tree was resulted from both decreased leaf assimilation rate (until about 23 % and 50 %, respectively under moderate and severe stress conditions compared to low stress conditions and decreased leaf area of tree (until about 57% and 79%, respectively under moderate and severe stress conditions compared to low stress conditions at harvest. The significant positive correlation between leaf water potential and vegetative growth of peach revealed that shoot growth would decrease by 30% and 50% of maximum at leaf water potential of –1.56 and –2.30 MPa, respectively.

How to make agricultural extension demand-driven?: The case of India's agricultural extension policy