WorldWideScience

Sample records for plant growth strategies

  1. Plant growth strategies are remodeled by spaceflight

    Directory of Open Access Journals (Sweden)

    Paul Anna-Lisa

    2012-12-01

    Full Text Available Abstract Background Arabidopsis plants were grown on the International Space Station within specialized hardware that combined a plant growth habitat with a camera system that can capture images at regular intervals of growth. The Imaging hardware delivers telemetric data from the ISS, specifically images received in real-time from experiments on orbit, providing science without sample return. Comparable Ground Controls were grown in a sister unit that is maintained in the Orbital Environment Simulator at Kennedy Space Center. One of many types of biological data that can be analyzed in this fashion is root morphology. Arabidopsis seeds were geminated on orbit on nutrient gel Petri plates in a configuration that encouraged growth along the surface of the gel. Photos were taken every six hours for the 15 days of the experiment. Results In the absence of gravity, but the presence of directional light, spaceflight roots remained strongly negatively phototropic and grew in the opposite direction of the shoot growth; however, cultivars WS and Col-0 displayed two distinct, marked differences in their growth patterns. First, cultivar WS skewed strongly to the right on orbit, while cultivar Col-0 grew with little deviation away from the light source. Second, the Spaceflight environment also impacted the rate of growth in Arabidopsis. The size of the Flight plants (as measured by primary root and hypocotyl length was uniformly smaller than comparably aged Ground Control plants in both cultivars. Conclusions Skewing and waving, thought to be gravity dependent phenomena, occur in spaceflight plants. In the presence of an orienting light source, phenotypic trends in skewing are gravity independent, and the general patterns of directional root growth typified by a given genotype in unit gravity are recapitulated on orbit, although overall growth patterns on orbit are less uniform. Skewing appears independent of axial orientation on the ISS – suggesting

  2. PLANT-MICROBIAL INTERACTIONS IN THE RHIZOSPHERE – STRATEGIES FOR PLANT GROWTH-PROMOTION

    Directory of Open Access Journals (Sweden)

    Marius Stefan

    2012-03-01

    Full Text Available Plant growth-promoting rhizobacteria (PGPR are a group of bacteria that can actively colonize plant rootsand enhance plant growth using different mechanisms: production of plant growth regulators like indoleacetic acid,gibberellic acid, cytokinins and ethylene(Zahir et al., 2003, providing the host plant with fixed nitrogen, solubilizationof soil phosphorus, enhance Fe uptake, biocontrol, reducing the concentration of heavy metals. PGPR are perfectcandidates to be used as biofertilizers – eco-friendly alternative to common applied chemical fertilizer in today’sagriculture. The most important benefit of PGPR usage is related to the reduction of environmental pollution in conditionof increasing crop yield. This review presents the main mechanisms involved in PGPR promotion of plant growth.

  3. A Monte Carlo/response surface strategy for sensitivity analysis: application to a dynamic model of vegetative plant growth

    Science.gov (United States)

    Lim, J. T.; Gold, H. J.; Wilkerson, G. G.; Raper, C. D. Jr; Raper CD, J. r. (Principal Investigator)

    1989-01-01

    We describe the application of a strategy for conducting a sensitivity analysis for a complex dynamic model. The procedure involves preliminary screening of parameter sensitivities by numerical estimation of linear sensitivity coefficients, followed by generation of a response surface based on Monte Carlo simulation. Application is to a physiological model of the vegetative growth of soybean plants. The analysis provides insights as to the relative importance of certain physiological processes in controlling plant growth. Advantages and disadvantages of the strategy are discussed.

  4. Plant growth-promoting bacteria: mechanisms and applications.

    Science.gov (United States)

    Glick, Bernard R

    2012-01-01

    The worldwide increases in both environmental damage and human population pressure have the unfortunate consequence that global food production may soon become insufficient to feed all of the world's people. It is therefore essential that agricultural productivity be significantly increased within the next few decades. To this end, agricultural practice is moving toward a more sustainable and environmentally friendly approach. This includes both the increasing use of transgenic plants and plant growth-promoting bacteria as a part of mainstream agricultural practice. Here, a number of the mechanisms utilized by plant growth-promoting bacteria are discussed and considered. It is envisioned that in the not too distant future, plant growth-promoting bacteria (PGPB) will begin to replace the use of chemicals in agriculture, horticulture, silviculture, and environmental cleanup strategies. While there may not be one simple strategy that can effectively promote the growth of all plants under all conditions, some of the strategies that are discussed already show great promise.

  5. Plant Growth-Promoting Bacteria: Mechanisms and Applications

    Directory of Open Access Journals (Sweden)

    Bernard R. Glick

    2012-01-01

    Full Text Available The worldwide increases in both environmental damage and human population pressure have the unfortunate consequence that global food production may soon become insufficient to feed all of the world's people. It is therefore essential that agricultural productivity be significantly increased within the next few decades. To this end, agricultural practice is moving toward a more sustainable and environmentally friendly approach. This includes both the increasing use of transgenic plants and plant growth-promoting bacteria as a part of mainstream agricultural practice. Here, a number of the mechanisms utilized by plant growth-promoting bacteria are discussed and considered. It is envisioned that in the not too distant future, plant growth-promoting bacteria (PGPB will begin to replace the use of chemicals in agriculture, horticulture, silviculture, and environmental cleanup strategies. While there may not be one simple strategy that can effectively promote the growth of all plants under all conditions, some of the strategies that are discussed already show great promise.

  6. Plant growth promoting bacteria as an alternative strategy for salt tolerance in plants: A review.

    Science.gov (United States)

    Numan, Muhammad; Bashir, Samina; Khan, Yasmin; Mumtaz, Roqayya; Shinwari, Zabta Khan; Khan, Abdul Latif; Khan, Ajmal; Al-Harrasi, Ahmed

    2018-04-01

    Approximately 5.2 billion hectare agriculture land are affected by erosion, salinity and soil degradation. Salinity stress has significantly affecting the fertile lands, and therefore possesses a huge impact on the agriculture and economy of a country. Salt stress has severe effects on the growth and development of plants as well as reducing its yield. Plants are inherently equipped with stress tolerance ability to responds the specific type of stress. Plants retained specific mechanisms for salt stress mitigation, such as hormonal stimulation, ion exchange, antioxidant enzymes and activation of signaling cascades on their metabolic and genetic frontiers that sooth the stressed condition. Additional to the plant inherent mechanisms, certain plant growth promoting bacteria (PGPB) also have specialized mechanism that play key role for salt stress tolerance and plant growth promotion. These bacteria triggers plants to produce different plant growth hormones like auxin, cytokinine and gibberellin as well as volatile organic compounds. These bacteria also produces growth regulators like siderophore, which fix nitrogen, solubilize organic and inorganic phosphate. Considering the importance of PGPB in compensation of salt tolerance in plants, the present study has reviewed the different aspect and mechanism of bacteria that play key role in promoting plants growth and yield. It can be concluded that PGPB can be used as a cost effective and economical tool for salinity tolerance and growth promotion in plants. Copyright © 2018 Elsevier GmbH. All rights reserved.

  7. 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

  8. Fast-slow continuum and reproductive strategies structure plant life-history variation worldwide.

    Science.gov (United States)

    Salguero-Gómez, Roberto; Jones, Owen R; Jongejans, Eelke; Blomberg, Simon P; Hodgson, David J; Mbeau-Ache, Cyril; Zuidema, Pieter A; de Kroon, Hans; Buckley, Yvonne M

    2016-01-05

    The identification of patterns in life-history strategies across the tree of life is essential to our prediction of population persistence, extinction, and diversification. Plants exhibit a wide range of patterns of longevity, growth, and reproduction, but the general determinants of this enormous variation in life history are poorly understood. We use demographic data from 418 plant species in the wild, from annual herbs to supercentennial trees, to examine how growth form, habitat, and phylogenetic relationships structure plant life histories and to develop a framework to predict population performance. We show that 55% of the variation in plant life-history strategies is adequately characterized using two independent axes: the fast-slow continuum, including fast-growing, short-lived plant species at one end and slow-growing, long-lived species at the other, and a reproductive strategy axis, with highly reproductive, iteroparous species at one extreme and poorly reproductive, semelparous plants with frequent shrinkage at the other. Our findings remain consistent across major habitats and are minimally affected by plant growth form and phylogenetic ancestry, suggesting that the relative independence of the fast-slow and reproduction strategy axes is general in the plant kingdom. Our findings have similarities with how life-history strategies are structured in mammals, birds, and reptiles. The position of plant species populations in the 2D space produced by both axes predicts their rate of recovery from disturbances and population growth rate. This life-history framework may complement trait-based frameworks on leaf and wood economics; together these frameworks may allow prediction of responses of plants to anthropogenic disturbances and changing environments.

  9. Plant Ecological Strategies Shift Across the Cretaceous–Paleogene Boundary

    Science.gov (United States)

    Blonder, Benjamin; Royer, Dana L.; Johnson, Kirk R.; Miller, Ian; Enquist, Brian J.

    2014-01-01

    The Chicxulub bolide impact caused the end-Cretaceous mass extinction of plants, but the associated selectivity and ecological effects are poorly known. Using a unique set of North Dakota leaf fossil assemblages spanning 2.2 Myr across the event, we show among angiosperms a reduction of ecological strategies and selection for fast-growth strategies consistent with a hypothesized recovery from an impact winter. Leaf mass per area (carbon investment) decreased in both mean and variance, while vein density (carbon assimilation rate) increased in mean, consistent with a shift towards “fast” growth strategies. Plant extinction from the bolide impact resulted in a shift in functional trait space that likely had broad consequences for ecosystem functioning. PMID:25225914

  10. A model of plant strategies in fluvial hydrosystems

    NARCIS (Netherlands)

    Bornette, G.; Tabacchi, E.; Hupp, C.; Puijalon, S.; Rostan, J.C.

    2008-01-01

    1. We propose a model of plant strategies in temperate fluvial hydrosystems that considers the hydraulic and geomorphic features that control plant recruitment, establishment and growth in river floodplains. 2. The model describes first how the disturbance gradient and the grain-size of the river

  11. Phosphate solubilization as a microbial strategy for promoting plant growth

    Directory of Open Access Journals (Sweden)

    Mayra Eleonora Beltrán Pineda

    2014-01-01

    Full Text Available Because of the constant application of chemical inputs in Agroecosystem, the cost of crop production and environmental quality of soil and water have been affected. Microorganisms carry out most biogeochemical cycles; therefore, their role is essential for agro ecosystem balance. One such functional group is the phosphate solubilizing microorganisms, which are recognized plant growth promoters. These microbial populations perform an important activity, since in many soils there are large reserves of insoluble phosphorus, as a result of fixing much of the phosphorus fertilizer applied, which cannot be assimilated by the plant. The phosphate solubilizing microorganisms use different solubilization mechanisms such as the production of organic acids, which solubilize theses insoluble phosphates in the rhizosphere region. Soluble phosphates are absorbed by the plant, which enhances their growth and productivity. By using these phosphate reserves in soils, application of chemical fertilizers is decreased, on the one hand, can again be fixed by ions Ca, Al or Fe making them insoluble and, by the other hand, increase the costs of crop production. Microbial populations have been widely studied in different types of ecosystems, both natural and Agroecosystem. Thanks to its effectiveness, in laboratory and field studies, the phosphate solubilizing phenotype is of great interest to microbial ecologists who have begun to establish the molecular basis of the traitr.

  12. Plant responses to plant growth-promoting rhizobacteria

    NARCIS (Netherlands)

    Loon, L.C. van

    2007-01-01

    Non-pathogenic soilborne microorganisms can promote plant growth, as well as suppress diseases. Plant growth promotion is taken to result from improved nutrient acquisition or hormonal stimulation. Disease suppression can occur through microbial antagonism or induction of resistance in the plant.

  13. Impact of accelerated plant growth on seed variety development

    Science.gov (United States)

    Christophersen, Eric

    1998-01-01

    The commercial lives of agricultural seed products have steadily declined in recent years. The introduction of genetically engineered crop seeds in 1966 has accentuated that trend. Widespread grower demand for genetically engineered seed requires competitive response by industry followers in order to avert market share losses to the industry leaders. Limitations on plant transformation technology, regulatory requirements and patent impediments require companies to rapidly convert transformed lines into elite commercial products. Massive multigenerational backcrossing efforts are required to distribute genetically engineered traits into a broad product mix. Significant incidents of expression failures, or ``gene silencing,'' have occurred unexpectedly, requiring product substitution strategies. First-to-market strategies, competitive response, broad germplasm conversion and rescue of product failures all share the element of urgency. Technologies which reliably accelerate product development rates can expect favorable reception by commercial seed developers. A growth chamber which dramatically accelerates the rate of plant growth is described.

  14. A comparison of stable caesium uptake by six grass species of contrasting growth strategy

    International Nuclear Information System (INIS)

    Willey, N.J.; Martin, M.H.

    1997-01-01

    Six plants in the family Gramineae were used to investigate the relationship between Cs uptake, nutrient regime and plant growth strategy sensu Grime (1979: Plant Growth Strategies and Vegetation Processes, John Wiley). The roots of 66 day old Elymus repens (L.) Gould., Bromus sterilis L., Agrostis stolonifera L., Anthoxanthum odoratum L., Festuca ovina L. and Nardus stricta L. plants grown in acid-washed sand at high and low nutrient levels were exposed to a 96 h pulse of stable Cs at 0.05 mM, 0.15 mM, 0.3 mM, 1.0 mM and 3.0 mM concentrations. Different nutrient regimes induced large differences in dry wt in E. repens, B. sterilis and A. stolonifera plants but only small differences in N. stricta and F. ovina plants. At high nutrient concentrations, A. stolonifera, A. odoratum, F. ovina and N. stricta shoots showed significantly greater increases in internal Cs concentration with rising external Cs concentrations than did E. repens and B. sterilis shoots. The relationship between increases in shoot and external Cs concentrations was statistically indistinguishable between species in plants grown at the low nutrient concentration. These patterns of Cs uptake ensured that with long-term high K concentrations the more competitive plants (E. repens and B. sterilis) accumulated higher concentrations of Cs from low external concentrations than did non-competitive plants or competitive plants grown at low nutrient levels. It is suggested that the relationship between plant growth strategy sensu Grime (1979) and Cs accumulation patterns may help to explain the different concentrations to which species accumulate radiocaesium from the soil. (author)

  15. Fast-slow continuum and reproductive strategies structure plant life-history variation worldwide

    DEFF Research Database (Denmark)

    Salguero-Gómez, Roberto; Jones, Owen R; Jongejans, Eelke

    2016-01-01

    The identification of patterns in life-history strategies across the tree of life is essential to our prediction of population persistence, extinction, and diversification. Plants exhibit a wide range of patterns of longevity, growth, and reproduction, but the general determinants of this enormous...... variation in life history are poorly understood. We use demographic data from 418 plant species in the wild, from annual herbs to supercentennial trees, to examine how growth form, habitat, and phylogenetic relationships structure plant life histories and to develop a framework to predict population...

  16. Phytochrome, plant growth and flowering

    Science.gov (United States)

    King, R. W.; Bagnall, D. J.

    1994-01-01

    Attempts to use artificially lit cabinets to grow plants identical to those growing in sunlight have provided compelling evidence of the importance of light quality for plant growth. Changing the balance of red (R) to far-red (FR) radiation, but with a fixed photosynthetic input can shift the phytochrome photoequilibrium in a plant and generate large differences in plant growth. With FR enrichment the plants elongate, and may produce more leaf area and dry matter. Similar morphogenic responses are also obtained when light quality is altered only briefly (15-30 min) at the end-of-the-day. Conversely, for plants grown in natural conditions the response of plant form to selective spectral filtering has again shown that red and far-red wavebands are important as found by Kasperbauer and coworkers. Also, where photosynthetic photon flux densities (PPFD) of sunlight have been held constant, the removal of far-red alone alters plant growth. With FR depletion plants grown in sunlight are small, more branched and darker green. Here we examine the implications for plant growth and flowering when the far-red composition of incident radiation in plant growth chambers is manipulated.

  17. Phytochrome, plant growth and flowering

    Energy Technology Data Exchange (ETDEWEB)

    King, R.W.; Bagnall, D.J. [CSIRO, Canberra (Australia)

    1994-12-31

    Attempts to use artificially lit cabinets to grow plants identical to those growing in sunlight have provided compelling evidence of the importance of light quality for plant growth. Changing the balance of red (R) to far-red (FR) radiation, but with a fixed photosynthetic input can shift the phytochrome photoequilibrium in a plant and generate large differences in plant growth. With FR enrichment the plants elongate, and may produce more leaf area and dry matter. Similar morphogenic responses are also obtained when light quality is altered only briefly (15-30 min) at the end-of-the-day. Conversely, for plants grown in natural conditions the response of plant form to selective spectral filtering has again shown that red and far-red wavebands are important as found by Kasperbauer and coworkers. Also, where photosynthetic photon flux densities (PPFD) of sunlight have been held constant, the removal of far-red alone alters plant growth. As shown for chrysanthemum, with FR depletion plants grown in sunlight are small, more branched and darker green. We examine the implications for plant growth and flowering when the far-red composition of incident radiation in plant growth chambers is manipulated.

  18. A Review of Plant Growth Substances

    Directory of Open Access Journals (Sweden)

    D.A. Agboola

    2014-10-01

    Full Text Available Plant growth substances are compounds, either natural or synthetic that modifies or controls through physiological action, the growth and maturation of plants. If the compound is produced within the plant, it is called a plant hormone or phytohormone. In general, it is accepted that there are five major classes of plant hormones. They are Auxins (IAA, Cytokinins, Gibberellins, Ethylene and Abscisic Acid. However, there are still many plant growth substances that cannot be grouped under these classes, though they also perform similar functions, inhibiting or promoting plant growth. These substances include Brassinosteroids (Brassins, Salicylic Acid, Jasmonic Acid, Fusicoccin, Batasins, Strigolactones, Growth stimulants (e.g. Hymexazol and Pyripropanol, Defoliants (e.g. Calcium Cyanamide, Dimethipin. Researchers are still working on the biosynthetic pathways of some of these substances. Plant growth substances are very useful in agriculture in both low and high concentrations. They affect seed growth, time of flowering, the sex of flowers, senescence of leaves and fruits, leaf formation, stem growth, fruit development and ripening, plant longevity, and even plant death. Some synthetic regulators are also used as herbicides and pesticides. Therefore, attention should be paid to the production and synthesis of these substances so that they affect plants in a way that would favour yield.

  19. [Review on application of plant growth retardants in medicinal plants cultivation].

    Science.gov (United States)

    Zhai, Yu-Yao; Guo, Bao-Lin; Cheng, Ming

    2013-09-01

    Plant growth retardants are widely used in cultivation of medicinal plant, but there is still lack of scientific guidance. In order to guide the use of plant growth retardants in medicinal plant cultivation efficiently and reasonably, this paper reviewed the mechanism, function characteristic, plant and soil residue of plant growth retardants, such as chlorocholine chloride, mepiquat chloride, paclobutrazol, unicnazle and succinic acid, and summarized the application of plant growth retardants in medicinal plants cultivation in recent years, with focus on the effect of growth and yield of the officinal organs and secondary metabolites.

  20. Growth rates of rhizosphere microorganisms depend on competitive abilities of plants for nitrogen

    Science.gov (United States)

    Blagodatskaya, Evgenia; Littschwager, Johanna; Lauerer, Marianna; Kuzyakov, Yakov

    2010-05-01

    estimated by fitting the parameters of the equation: CO2(t) = A + B × exp(µ×t), to the measured CO2 production rate (CO2(t)) after glucose addition, where A is the initial respiration rate uncoupled from ATP production, B the initial rate of the growing fraction of total respiration coupled with ATP generation and cell growth, and t time. Our study revealed the linkage between growth strategies of rhizosphere microorganisms and different adaptation strategies of F. vesca and D. indica to N limitation. Plant - strong competitor for N (D. indica) did not change root mass under N limitation causing the deficit of N in the rhizosphere and altering the structure of rhizosphere microbial community. Benefiting of slow growing microorganisms with K-strategy under N limiting conditions was indicated by strong decrease in specific microbial growth rates in the rhizosphere of D. indica. Root mass of the plant with weak competitive abilities for N (F. vesca) increased under lack of N to compensate the lack of nutrients. The increase in root mass and possible increase in amount of root exudates coincided with no structural changes in microbial community in rhizosphere of F. vesca. By intraspecific competition at low N level a 2.4-fold slower microbial specific growth rates were observed under D. indica (0.09 h-1) characterized by smaller root biomass and lower N content in roots compared with F. vesca. The generation time of actively growing microbial biomass was for the 6 hours longer in rhizosphere of D. indica than under F. vesca (10.7 to 4.6 h, respectively). Thus, under N limitation the strong competition for N between plant and microorganisms decreased microbial growth rates and carbon turnover in rhizosphere. By interspecific competition of both plants at low N level, microbial growth rates were similar to those for D. indica indicating that plant with stronger competitive abilities for N controls microbial community in the rhizosphere. At high N availability the root biomass

  1. Growth strategy, phylogeny and stoichiometry determine the allelopathic potential of native and non-native plants

    NARCIS (Netherlands)

    Grutters, Bart M.C.; Saccomanno, Benedetta; Gross, Elisabeth M.; Van de Waal, Dedmer B.; van Donk, Ellen; Bakker, Elisabeth S.

    2017-01-01

    Secondary compounds can contribute to the success of non-native plant species if they reduce damage by native herbivores or inhibit the growth of native plant competitors. However, there is opposing evidence on whether the secondary com- pounds of non-native plant species are stronger than those of

  2. The microbiome of medicinal plants: diversity and importance for plant growth, quality and health.

    Science.gov (United States)

    Köberl, Martina; Schmidt, Ruth; Ramadan, Elshahat M; Bauer, Rudolf; Berg, Gabriele

    2013-12-20

    Past medicinal plant research primarily focused on bioactive phytochemicals, however, the focus is currently shifting due to the recognition that a significant number of phytotherapeutic compounds are actually produced by associated microbes or through interaction with their host. Medicinal plants provide an enormous bioresource of potential use in modern medicine and agriculture, yet their microbiome is largely unknown. The objective of this review is (i) to introduce novel insights into the plant microbiome with a focus on medicinal plants, (ii) to provide details about plant- and microbe-derived ingredients of medicinal plants, and (iii) to discuss possibilities for plant growth promotion and plant protection for commercial cultivation of medicinal plants. In addition, we also present a case study performed both to analyse the microbiome of three medicinal plants (Matricaria chamomilla L., Calendula officinalis L., and Solanum distichum Schumach. and Thonn.) cultivated on organically managed Egyptian desert farm and to develop biological control strategies. The soil microbiome of the desert ecosystem was comprised of a high abundance of Gram-positive bacteria of prime importance for pathogen suppression under arid soil conditions. For all three plants, we observed a clearly plant-specific selection of the microbes as well as highly specific diazotrophic communities that overall identify plant species as important drivers in structural and functional diversity. Lastly, native Bacillus spec. div. strains were able to promote plant growth and elevate the plants' flavonoid production. These results underline the numerous links between the plant-associated microbiome and the plant metabolome.

  3. Combined use of alkane-degrading and plant growth-promoting bacteria enhanced phytoremediation of diesel contaminated soil.

    Science.gov (United States)

    Tara, Nain; Afzal, Muhammad; Ansari, Tariq M; Tahseen, Razia; Iqbal, Samina; Khan, Qaiser M

    2014-01-01

    Inoculation of plants with pollutant-degrading and plant growth-promoting microorganisms is a simple strategy to enhance phytoremediation activity. The objective of this study was to determine the effect of inoculation of different bacterial strains, possessing alkane-degradation and 1-amino-cyclopropane-1 -carboxylic acid (ACC) deaminase activity, on plant growth and phytoremediation activity. Carpet grass (Axonopus affinis) was planted in soil spiked with diesel (1% w/w) for 90 days and inoculated with different bacterial strains, Pseudomonas sp. ITRH25, Pantoea sp. BTRH79 and Burkholderia sp. PsJN, individually and in combination. Generally, bacterial application increased total numbers of culturable hydrocarbon-degrading bacteria in the rhizosphere ofcarpet grass, plant biomass production, hydrocarbon degradation and reduced genotoxicity. Bacterial strains possessing different beneficial traits affect plant growth and phytoremediation activity in different ways. Maximum bacterial population, plant biomass production and hydrocarbon degradation were achieved when carpet grass was inoculated with a consortium of three strains. Enhanced plant biomass production and hydrocarbon degradation were associated with increased numbers of culturable hydrocarbon-degrading bacteria in the rhizosphere of carpet grass. The present study revealed that the combined use of different bacterial strains, exhibiting different beneficial traits, is a highly effective strategy to improve plant growth and phytoremediation activity.

  4. Host plant invests in growth rather than chemical defense when attacked by a specialist herbivore.

    Science.gov (United States)

    Arab, Alberto; Trigo, José Roberto

    2011-05-01

    Plant defensive compounds may be a cost rather than a benefit when plants are attacked by specialist insects that may overcome chemical barriers by strategies such as sequestering plant compounds. Plants may respond to specialist herbivores by compensatory growth rather than chemical defense. To explore the use of defensive chemistry vs. compensatory growth we studied Brugmansia suaveolens (Solanaceae) and the specialist larvae of the ithomiine butterfly Placidina euryanassa, which sequester defensive tropane alkaloids (TAs) from this host plant. We investigated whether the concentration of TAs in B. suaveolens was changed by P. euryanassa damage, and whether plants invest in growth, when damaged by the specialist. Larvae feeding during 24 hr significantly decreased TAs in damaged plants, but they returned to control levels after 15 days without damage. Damaged and undamaged plants did not differ significantly in leaf area after 15 days, indicating compensatory growth. Our results suggest that B. suaveolens responds to herbivory by the specialist P. euryanassa by investing in growth rather than chemical defense.

  5. APPLICATION OF DRIP IRRIGATION ON COTTON PLANT GROWTH (Gossypium sp.

    Directory of Open Access Journals (Sweden)

    Syahruni Thamrin

    2017-12-01

    Full Text Available The condition of cotton planting in South Sulawesi is always constrained in the fulfillment of water. All plant growth stages are not optimal to increase production, so it is necessary to introduce good water management technology, such as through water supply with drip irrigation system. This study aims to analyze the strategy of irrigation management in cotton plants using drip irrigation system. Model of application by designing drip irrigation system and cotton planting on land prepared as demonstration plot. Observations were made in the germination phase and the vegetative phase of the early plants. Based on the result of drip irrigation design, the emitter droplet rate (EDR was 34.266 mm/hour with an operational time of 4.08 min/day. From the observation of cotton growth, it is known that germination time lasted from 6 to 13 days after planting, the average plant height reached 119.66 cm, with the number of leaves averaging 141.93 pieces and the number of bolls averaging 57.16 boll.

  6. The microbiome of medicinal plants: diversity and importance for plant growth, quality and health

    Directory of Open Access Journals (Sweden)

    Martina eKöberl

    2013-12-01

    Full Text Available Past medicinal plant research primarily focused on bioactive phytochemicals, however the focus is currently shifting due to the recognition that a significant number of phytotherapeutic compounds are actually produced by associated microbes or through interaction with their host. Medicinal plants provide an enormous bioresource of potential use in modern medicine and agriculture, yet their microbiome is largely unknown. The objective of this review is i to introduce novel insights into the plant microbiome with a focus on medicinal plants, ii to provide details about plant- and microbe-derived ingredients of medicinal plants, and iii to discuss possibilities for plant growth promotion and plant protection for commercial cultivation of medicinal plants. In addition, we also present a case study performed both to analyse the microbiome of three medicinal plants (Matricaria chamomilla L., Calendula officinalis L. and Solanum distichum Schumach. and Thonn. cultivated on organically managed Egyptian desert farm and to develop biological control strategies. The soil microbiome of the desert ecosystem was comprised of a high abundance of Gram-positive bacteria of prime importance for pathogen suppression under arid soil conditions. For all three plants, we observed a clearly plant-specific selection of the microbes as well as highly specific diazotrophic communities that overall identify plant species as important drivers in structural and functional diversity. Lastly, native Bacillus spec. div. strains were able to promote plant growth and elevate the plants’ flavonoid production. These results underline the numerous links between the plant-associated microbiome and the plant metabolome.

  7. Plant-mediated restriction of Salmonella enterica on tomato and spinach leaves colonized with Pseudomonas plant growth-promoting rhizobacteria.

    Science.gov (United States)

    Hsu, Chiun-Kang; Micallef, Shirley A

    2017-10-16

    Reducing Salmonella enterica association with plants during crop production could reduce risks of fresh produce-borne salmonellosis. Plant growth-promoting rhizobacteria (PGPR) colonizing plant roots are capable of promoting plant growth and boosting resistance to disease, but the effects of PGPR on human pathogen-plant associations are not known. Two root-colonizing Pseudomonas strains S2 and S4 were investigated in spinach, lettuce and tomato for their plant growth-promoting properties and their influence on leaf populations of S. enterica serovar Newport. Plant roots were inoculated with Pseudomonas in the seedling stage. At four (tomato) and six (spinach and lettuce) weeks post-germination, plant growth promotion was assessed by shoot dry weight (SDW) and leaf chlorophyll content measurements. Leaf populations of S. Newport were measured after 24h of leaf inoculation with this pathogen by direct plate counts on Tryptic Soy Agar. Root inoculation of spinach cv. 'Tyee', with Pseudomonas strain S2 or S4 resulted in a 69% and 63% increase in SDW compared to non-inoculated controls (pgrowth by over 40% compared to controls (pgrowth promotion was detected in tomato cv. 'BHN602', but S2-inoculated plants had elevated leaf chlorophyll content (13%, pgrowth, but also reduce the fitness of epiphytic S. enterica in the phyllosphere. Plant-mediated effects induced by PGPR may be an effective strategy to minimize contamination of crops with S. enterica during cultivation. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Plant growth-promoting rhizobacteria (PGPR: their potential as antagonists and biocontrol agents

    Directory of Open Access Journals (Sweden)

    Anelise Beneduzi

    2012-01-01

    Full Text Available Bacteria that colonize plant roots and promote plant growth are referred to as plant growth-promoting rhizobacteria (PGPR. PGPR are highly diverse and in this review we focus on rhizobacteria as biocontrol agents. Their effects can occur via local antagonism to soil-borne pathogens or by induction of systemic resistance against pathogens throughout the entire plant. Several substances produced by antagonistic rhizobacteria have been related to pathogen control and indirect promotion of growth in many plants, such as siderophores and antibiotics. Induced systemic resistance (ISR in plants resembles pathogen-induced systemic acquired resistance (SAR under conditions where the inducing bacteria and the challenging pathogen remain spatially separated. Both types of induced resistance render uninfected plant parts more resistant to pathogens in several plant species. Rhizobacteria induce resistance through the salicylic acid-dependent SAR pathway, or require jasmonic acid and ethylene perception from the plant for ISR. Rhizobacteria belonging to the genera Pseudomonas and Bacillus are well known for their antagonistic effects and their ability to trigger ISR. Resistance-inducing and antagonistic rhizobacteria might be useful in formulating new inoculants with combinations of different mechanisms of action, leading to a more efficient use for biocontrol strategies to improve cropping systems.

  9. Phylogenetic escalation and decline of plant defense strategies

    Science.gov (United States)

    Agrawal, Anurag A.; Fishbein, Mark

    2008-01-01

    As the basal resource in most food webs, plants have evolved myriad strategies to battle consumption by herbivores. Over the past 50 years, plant defense theories have been formulated to explain the remarkable variation in abundance, distribution, and diversity of secondary chemistry and other defensive traits. For example, classic theories of enemy-driven evolutionary dynamics have hypothesized that defensive traits escalate through the diversification process. Despite the fact that macroevolutionary patterns are an explicit part of defense theories, phylogenetic analyses have not been previously attempted to disentangle specific predictions concerning (i) investment in resistance traits, (ii) recovery after damage, and (iii) plant growth rate. We constructed a molecular phylogeny of 38 species of milkweed and tested four major predictions of defense theory using maximum-likelihood methods. We did not find support for the growth-rate hypothesis. Our key finding was a pattern of phyletic decline in the three most potent resistance traits (cardenolides, latex, and trichomes) and an escalation of regrowth ability. Our neontological approach complements more common paleontological approaches to discover directional trends in the evolution of life and points to the importance of natural enemies in the macroevolution of species. The finding of macroevolutionary escalating regowth ability and declining resistance provides a window into the ongoing coevolutionary dynamics between plants and herbivores and suggests a revision of classic plant defense theory. Where plants are primarily consumed by specialist herbivores, regrowth (or tolerance) may be favored over resistance traits during the diversification process. PMID:18645183

  10. Mum, why do you keep on growing? Impacts of environmental variability on optimal growth and reproduction allocation strategies of annual plants.

    Science.gov (United States)

    De Lara, Michel

    2006-05-01

    In their 1990 paper Optimal reproductive efforts and the timing of reproduction of annual plants in randomly varying environments, Amir and Cohen considered stochastic environments consisting of i.i.d. sequences in an optimal allocation discrete-time model. We suppose here that the sequence of environmental factors is more generally described by a Markov chain. Moreover, we discuss the connection between the time interval of the discrete-time dynamic model and the ability of the plant to rebuild completely its vegetative body (from reserves). We formulate a stochastic optimization problem covering the so-called linear and logarithmic fitness (corresponding to variation within and between years), which yields optimal strategies. For "linear maximizers'', we analyse how optimal strategies depend upon the environmental variability type: constant, random stationary, random i.i.d., random monotonous. We provide general patterns in terms of targets and thresholds, including both determinate and indeterminate growth. We also provide a partial result on the comparison between ;"linear maximizers'' and "log maximizers''. Numerical simulations are provided, allowing to give a hint at the effect of different mathematical assumptions.

  11. Less favourable climates constrain demographic strategies in plants.

    Science.gov (United States)

    Csergő, Anna M; Salguero-Gómez, Roberto; Broennimann, Olivier; Coutts, Shaun R; Guisan, Antoine; Angert, Amy L; Welk, Erik; Stott, Iain; Enquist, Brian J; McGill, Brian; Svenning, Jens-Christian; Violle, Cyrille; Buckley, Yvonne M

    2017-08-01

    Correlative species distribution models are based on the observed relationship between species' occurrence and macroclimate or other environmental variables. In climates predicted less favourable populations are expected to decline, and in favourable climates they are expected to persist. However, little comparative empirical support exists for a relationship between predicted climate suitability and population performance. We found that the performance of 93 populations of 34 plant species worldwide - as measured by in situ population growth rate, its temporal variation and extinction risk - was not correlated with climate suitability. However, correlations of demographic processes underpinning population performance with climate suitability indicated both resistance and vulnerability pathways of population responses to climate: in less suitable climates, plants experienced greater retrogression (resistance pathway) and greater variability in some demographic rates (vulnerability pathway). While a range of demographic strategies occur within species' climatic niches, demographic strategies are more constrained in climates predicted to be less suitable. © 2017 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

  12. Spaceflight hardware for conducting plant growth experiments in space: the early years 1960-2000

    Science.gov (United States)

    Porterfield, D. M.; Neichitailo, G. S.; Mashinski, A. L.; Musgrave, M. E.

    2003-01-01

    The best strategy for supporting long-duration space missions is believed to be bioregenerative life support systems (BLSS). An integral part of a BLSS is a chamber supporting the growth of higher plants that would provide food, water, and atmosphere regeneration for the human crew. Such a chamber will have to be a complete plant growth system, capable of providing lighting, water, and nutrients to plants in microgravity. Other capabilities include temperature, humidity, and atmospheric gas composition controls. Many spaceflight experiments to date have utilized incomplete growth systems (typically having a hydration system but lacking lighting) to study tropic and metabolic changes in germinating seedlings and young plants. American, European, and Russian scientists have also developed a number of small complete plant growth systems for use in spaceflight research. Currently we are entering a new era of experimentation and hardware development as a result of long-term spaceflight opportunities available on the International Space Station. This is already impacting development of plant growth hardware. To take full advantage of these new opportunities and construct innovative systems, we must understand the results of past spaceflight experiments and the basic capabilities of the diverse plant growth systems that were used to conduct these experiments. The objective of this paper is to describe the most influential pieces of plant growth hardware that have been used for the purpose of conducting scientific experiments during the first 40 years of research. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

  13. Fast–slow continuum and reproductive strategies structure plant life-history variation worldwide

    NARCIS (Netherlands)

    Salguero-Gómez, Roberto; Jones, Owen R.; Jongejans, Eelke; Blomberg, Simon; Hodgson, D.; Zuidema, P.A.; Kroon, de Hans; Buckley, Yvonne M.

    2016-01-01

    The identification of patterns in life-history strategies across the tree of life is essential to our prediction of population persistence, extinction, and diversification. Plants exhibit a wide range of patterns of longevity, growth, and reproduction, but the general determinants of this enormous

  14. Plant Growth-Promoting Rhizobacteria Stimulate Vegetative Growth and Asexual Reproduction of Kalanchoe daigremontiana.

    Science.gov (United States)

    Park, Yong-Soon; Park, Kyungseok; Kloepper, Joseph W; Ryu, Choong-Min

    2015-09-01

    Certain bacterial species associate with plant roots in soil. The plant growth-promoting rhizobacteria (PGPR) stimulate plant growth and yield in greenhouse and field. Here, we examined whether application of known bacilli PGPR strains stimulated growth and asexual reproduction in the succulent plant Kalanchoe daigremontiana. Four PGPR strains B. amyloliquefaciens IN937a, B. cereus BS107, B. pumilus INR7, and B. subtilis GB03 were applied to young plantlets by soil-drenching, and plant growth and development was monitored for three months. Aerial growth was significantly stimulated in PGPR-inoculated plants, which was observed as increases in plant height, shoot weight, and stem width. The stimulated growth influenced plant development by increasing the total number of leaves per plant. Treatment with bacilli also increased the total root biomass compared with that of control plants, and led to a 2-fold increase in asexual reproduction and plantlet formation on the leaf. Collectively, our results firstly demonstrate that Bacillus spp. promote vegetative development of K. daigremontiana, and the enhanced growth stimulates asexual reproduction and plantlet formation.

  15. Plant Growth-Promoting Rhizobacteria Stimulate Vegetative Growth and Asexual Reproduction of Kalanchoe daigremontiana

    Directory of Open Access Journals (Sweden)

    Yong-Soon Park

    2015-09-01

    Full Text Available Certain bacterial species associate with plant roots in soil. The plant growth-promoting rhizobacteria (PGPR stimulate plant growth and yield in greenhouse and field. Here, we examined whether application of known bacilli PGPR strains stimulated growth and asexual reproduction in the succulent plant Kalanchoe daigremontiana. Four PGPR strains B. amyloliquefaciens IN937a, B. cereus BS107, B. pumilus INR7, and B. subtilis GB03 were applied to young plantlets by soil-drenching, and plant growth and development was monitored for three months. Aerial growth was significantly stimulated in PGPR-inoculated plants, which was observed as increases in plant height, shoot weight, and stem width. The stimulated growth influenced plant development by increasing the total number of leaves per plant. Treatment with bacilli also increased the total root biomass compared with that of control plants, and led to a 2-fold increase in asexual reproduction and plantlet formation on the leaf. Collectively, our results firstly demonstrate that Bacillus spp. promote vegetative development of K. daigremontiana, and the enhanced growth stimulates asexual reproduction and plantlet formation.

  16. Martian Soil Plant Growth Experiment: The Effects of Adding Nitrogen, Bacteria, and Fungi to Enhance Plant Growth

    Science.gov (United States)

    Kliman, D. M.; Cooper, J. B.; Anderson, R. C.

    2000-01-01

    Plant growth is enhanced by the presence of symbiotic soil microbes. In order to better understand how plants might prosper on Mars, we set up an experiment to test whether symbiotic microbes function to enhance plant growth in a Martian soil simulant.

  17. Categorizing the Growth Strategies of Small Firms

    Directory of Open Access Journals (Sweden)

    Mika Westerlund

    2012-05-01

    Full Text Available This study investigates the link between a small firm’s investment in R&D and its growth strategy. A firm’s growth strategy refers to the means by which the organization plans to achieve its objective to grow in volume and turnover. We categorize firm growth strategies into eight distinctive clusters: opportunity explorers, radical innovators, business developers, business expanders, profit makers, business rebuilders, stagnators, and downsizers. We argue that understanding a firm’s growth orientation provides a way to assess the returns of its R&D investments, because an organization’s intangible growth strategies and tangible inputs are connected.

  18. Plant growth-promoting actinobacteria: a new strategy for enhancing sustainable production and protection of grain legumes.

    Science.gov (United States)

    Sathya, Arumugam; Vijayabharathi, Rajendran; Gopalakrishnan, Subramaniam

    2017-06-01

    Grain legumes are a cost-effective alternative for the animal protein in improving the diets of the poor in South-East Asia and Africa. Legumes, through symbiotic nitrogen fixation, meet a major part of their own N demand and partially benefit the following crops of the system by enriching soil. In realization of this sustainability advantage and to promote pulse production, United Nations had declared 2016 as the "International Year of pulses". Grain legumes are frequently subjected to both abiotic and biotic stresses resulting in severe yield losses. Global yields of legumes have been stagnant for the past five decades in spite of adopting various conventional and molecular breeding approaches. Furthermore, the increasing costs and negative effects of pesticides and fertilizers for crop production necessitate the use of biological options of crop production and protection. The use of plant growth-promoting (PGP) bacteria for improving soil and plant health has become one of the attractive strategies for developing sustainable agricultural systems due to their eco-friendliness, low production cost and minimizing consumption of non-renewable resources. This review emphasizes on how the PGP actinobacteria and their metabolites can be used effectively in enhancing the yield and controlling the pests and pathogens of grain legumes.

  19. Functional strategies of tropical dry forest plants in relation to growth form and isotopic composition

    Science.gov (United States)

    Santiago, L. S.; Silvera, K.; Andrade, J. L.; Dawson, T. E.

    2017-11-01

    Tropical dry forests (TDFs) undergo a substantial dry season in which plant species must endure several months of drought. Although TDFs support a diverse array of plant growth forms, it is not clear how they vary in mechanisms for coping with seasonal drought. We measured organic tissue stable isotopic composition of carbon (δ13C) and nitrogen (δ15N) across six plant growth forms including epiphytes, terrestrial succulents, trees, shrubs, herbs, and vines, and oxygen (δ18O) of four growth forms, to distinguish among patterns of resource acquisition and evaluate mechanisms for surviving annual drought in a lowland tropical dry forest in Yucatan, Mexico. Terrestrial succulent and epiphyte δ13C was around -14‰, indicating photosynthesis through the Crassulacean acid metabolism pathway, and along with one C4 herb were distinct from mean values of all other growth forms, which were between -26 and -29‰ indicating C3 photosynthesis. Mean tissue δ15N across epiphytes was -4.95‰ and was significantly lower than all other growth forms, which had values around +3‰. Tissue N concentration varied significantly among growth forms with epiphytes and terrestrial succulents having significantly lower values of about 1% compared to trees, shrubs, herbs and vines, which were around 3%. Tissue C concentration was highest in trees, shrubs and vines, intermediate in herbs and epiphytes and lowest in terrestrial succulents. δ18O did not vary among growth forms. Overall, our results suggest several water-saving aspects of resource acquisition, including the absolute occurrence of CAM photosynthesis in terrestrial succulents and epiphytes, high concentrations of leaf N in some species, which may facilitate CO2 drawdown by photosynthetic enzymes for a given stomatal conductance, and potentially diverse N sources ranging from atmospheric N in epiphytes with extremely depleted δ15N values, and a large range of δ15N values among trees, many of which are legumes and dry season

  20. Emerging microbial biocontrol strategies for plant pathogens.

    Science.gov (United States)

    Syed Ab Rahman, Sharifah Farhana; Singh, Eugenie; Pieterse, Corné M J; Schenk, Peer M

    2018-02-01

    To address food security, agricultural yields must increase to match the growing human population in the near future. There is now a strong push to develop low-input and more sustainable agricultural practices that include alternatives to chemicals for controlling pests and diseases, a major factor of heavy losses in agricultural production. Based on the adverse effects of some chemicals on human health, the environment and living organisms, researchers are focusing on potential biological control microbes as viable alternatives for the management of pests and plant pathogens. There is a growing body of evidence that demonstrates the potential of leaf and root-associated microbiomes to increase plant efficiency and yield in cropping systems. It is important to understand the role of these microbes in promoting growth and controlling diseases, and their application as biofertilizers and biopesticides whose success in the field is still inconsistent. This review focusses on how biocontrol microbes modulate plant defense mechanisms, deploy biocontrol actions in plants and offer new strategies to control plant pathogens. Apart from simply applying individual biocontrol microbes, there are now efforts to improve, facilitate and maintain long-term plant colonization. In particular, great hopes are associated with the new approaches of using "plant-optimized microbiomes" (microbiome engineering) and establishing the genetic basis of beneficial plant-microbe interactions to enable breeding of "microbe-optimized crops". Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Chemical Control of Plant Growth.

    Science.gov (United States)

    Agricultural Research Center (USDA), Beltsville, MD.

    Seven experiments are presented in this Science Study Aid to help students investigate the control of plant growth with chemicals. Plant growth regulators, weed control, and chemical pruning are the topics studied in the experiments which are based on investigations that have been and are being conducted at the U. S. Agricultural Research Center,…

  2. The plant economics spectrum is structured by leaf habits and growth forms across subtropical species.

    Science.gov (United States)

    Zhao, Yan-Tao; Ali, Arshad; Yan, En-Rong

    2017-02-01

    The plant economics spectrum that integrates the combination of leaf and wood syndromes provides a useful framework for the examination of species strategies at the whole-plant level. However, it remains unclear how species that differ in leaf habits and growth forms are integrated within the plant economics spectrum in subtropical forests. We measured five leaf and six wood traits across 58 subtropical plant species, which represented two leaf habits (evergreen vs deciduous) and two growth forms (tree vs shrub) in eastern China. Principal component analysis (PCA) was employed separately to construct the leaf (LES), wood (WES) and whole-plant (WPES) economics spectra. Leaf and wood traits are highly intra- and intercorrelated, thus defining not only the LES and WES, but also a WPES. Multi-trait variations in PCAs revealed that the traits which were representative of the acquisitive strategy, i.e., cheap tissue investment and rapid returns on that investment, were clustered at one end, while traits that represented the conservative strategy, i.e., expensive tissue investment and slower returns, were clustered at other end in each of the axes of the leaf and wood syndromes (PC1-axis) and the plant height strategy (PC2-axis). The local WPES, LES and WES were tightly correlated with each other. Evergreens shaped the conservative side, while deciduous species structured the acquisitive side of the WPES and LES. With respect to plant height strategies, trees formulated the acquisitive side and shrub species made up the conservative side of the WPES, LES and WES. In conclusion, our results suggested that the LES and WES were coordinated to a WPES for subtropical species. The finding of this local spectrum of plant form and function would be beneficial for modeling nutrient fluxes and species compositions in the changing climate, but also for understanding species strategies in an evolutionary context. © The Author 2016. Published by Oxford University Press. All rights

  3. A literature review on growth models and strategies: The missing link in entrepreneurial growth

    Directory of Open Access Journals (Sweden)

    Syed Fida Hussain Shah

    2013-08-01

    Full Text Available This study focuses on the importance of growth models, growth strategies, role of knowledge management system in the formulation of effective strategy for the enterprises following growth. Choice of an appropriate growth strategy is at the heart of any successful entrepreneurial venture. Selection of a strategy may be effective for one entrepreneur while it is not for other. Choice of Growth Strategy depends on various different factors, organisational context and environment which may vary from enterprise to enterprise. Resource based view is very important consideration for the entrepreneurs on the path of growth. Evaluation of all kind of resources helps them to grow their enterprises successfully. Selection of an appropriate growth strategy allows the entrepreneurs in overcoming growth challenges and avoiding the growth reversals and setbacks.

  4. Synthetic strategies for plant signalling studies: molecular toolbox and orthogonal platforms

    KAUST Repository

    Braguy, Justine

    2016-05-26

    Plants deploy a wide array of signalling networks integrating environmental cues with growth, defence and developmental responses. The high level of complexity, redundancy and connection between several pathways hampers a comprehensive understanding of involved functional and regulatory mechanisms. The implementation of synthetic biology approaches is revolutionizing experimental biology in prokaryotes, yeasts and animal systems and can likewise contribute to a new era in plant biology. This review gives an overview on synthetic biology approaches for the development and implementation of synthetic molecular tools and techniques to interrogate, understand and control signalling events in plants, ranging from strategies for the targeted manipulation of plant genomes up to the spatiotemporally resolved control of gene expression using optogenetic approaches. We also describe strategies based on the partial reconstruction of signalling pathways in orthogonal platforms, like yeast, animal and in vitro systems. This allows a targeted analysis of individual signalling hubs devoid of inter-connectivity with endogenous interacting components. Implementation of the interdisciplinary synthetic biology tools and strategies is not exempt of challenges and hardships but simultaneously most rewarding in terms of the advances in basic and applied research. As witnessed in other areas, these original theoretical-experimental avenues will lead to a breakthrough in the ability to study and comprehend plant signalling networks. This article is protected by copyright. All rights reserved.

  5. Intelligent Growth Automaton of Virtual Plant Based on Physiological Engine

    Science.gov (United States)

    Zhu, Qingsheng; Guo, Mingwei; Qu, Hongchun; Deng, Qingqing

    In this paper, a novel intelligent growth automaton of virtual plant is proposed. Initially, this intelligent growth automaton analyzes the branching pattern which is controlled by genes and then builds plant; moreover, it stores the information of plant growth, provides the interface between virtual plant and environment, and controls the growth and development of plant on the basis of environment and the function of plant organs. This intelligent growth automaton can simulate that the plant growth is controlled by genetic information system, and the information of environment and the function of plant organs. The experimental results show that the intelligent growth automaton can simulate the growth of plant conveniently and vividly.

  6. Error estimation in plant growth analysis

    Directory of Open Access Journals (Sweden)

    Andrzej Gregorczyk

    2014-01-01

    Full Text Available The scheme is presented for calculation of errors of dry matter values which occur during approximation of data with growth curves, determined by the analytical method (logistic function and by the numerical method (Richards function. Further formulae are shown, which describe absolute errors of growth characteristics: Growth rate (GR, Relative growth rate (RGR, Unit leaf rate (ULR and Leaf area ratio (LAR. Calculation examples concerning the growth course of oats and maize plants are given. The critical analysis of the estimation of obtained results has been done. The purposefulness of joint application of statistical methods and error calculus in plant growth analysis has been ascertained.

  7. Modelling asymmetric growth in crowded plant communities

    DEFF Research Database (Denmark)

    Damgaard, Christian

    2010-01-01

    A class of models that may be used to quantify the effect of size-asymmetric competition in crowded plant communities by estimating a community specific degree of size-asymmetric growth for each species in the community is suggested. The model consists of two parts: an individual size......-asymmetric growth part, where growth is assumed to be proportional to a power function of the size of the individual, and a term that reduces the relative growth rate as a decreasing function of the individual plant size and the competitive interactions from other plants in the neighbourhood....

  8. Effects of planting date and plant density on crop growth of cut chrysanthemum

    NARCIS (Netherlands)

    Lee, J.H.; Heuvelink, E.; Challa, H.

    2002-01-01

    The effects of planting date (season) and plant density (32, 48 or 64 plants m-2) on growth of cut chrysanthemum (Chrysanthemum (Indicum group)) were investigated in six greenhouse experiments, applying the expolinear growth equation. Final plant fresh and dry mass and number of flowers per plant

  9. Effect of metal tolerant plant growth promoting bacteria on growth and metal accumulation in Zea mays plants grown in fly ash amended soil.

    Science.gov (United States)

    Kumar, Kalpna V; Patra, D D

    2013-01-01

    The present study was undertaken to examine the effect of the application of fly ash (FA) into Garden soil (GS), with and without inoculation of plant growth promoting bacteria (PGPB), on the growth and metal uptake by Zea mays plants. Three FA tolerant PGPB strains, Pseudomonas sp. PS5, PS14, and Bacillus sp. BC29 were isolated from FA contaminated soils and assessed for their plant growth promoting features on the Z. mays plants. All three strains were also examined for their ability to solubilize phosphate and to produce Indole Acetic Acid (IAA), siderophores, and hydrogencynide acid (HCN) production. Although inoculation of all strains significantly enhanced the growth of plants at both the concentration of FA but maximum growth was observed in plants inoculated with BC29 and PS14 at low level (25%) of FA concentration. The experimental results explored the plant growth promoting features of selected strains which not only enhanced growth and biomass of plants but also protected them from toxicity of FA.

  10. Mining Halophytes for Plant Growth-Promoting Halotolerant Bacteria to Enhance the Salinity Tolerance of Non-halophytic Crops

    Directory of Open Access Journals (Sweden)

    Hassan Etesami

    2018-02-01

    Full Text Available Salinity stress is one of the major abiotic stresses limiting crop production in arid and semi-arid regions. Interest is increasing in the application of PGPRs (plant growth promoting rhizobacteria to ameliorate stresses such as salinity stress in crop production. The identification of salt-tolerant, or halophilic, PGPRs has the potential to promote saline soil-based agriculture. Halophytes are a useful reservoir of halotolerant bacteria with plant growth-promoting capabilities. Here, we review recent studies on the use of halophilic PGPRs to stimulate plant growth and increase the tolerance of non-halophytic crops to salinity. These studies illustrate that halophilic PGPRs from the rhizosphere of halophytic species can be effective bio-inoculants for promoting the production of non-halophytic species in saline soils. These studies support the viability of bioinoculation with halophilic PGPRs as a strategy for the sustainable enhancement of non-halophytic crop growth. The potential of this strategy is discussed within the context of ensuring sustainable food production for a world with an increasing population and continuing climate change. We also explore future research needs for using halotolerant PGPRs under salinity stress.

  11. Growth of fluoride treated Kalanchoe pinnata plants

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, H N; Applegate, H G

    1962-01-01

    Kalanchoe pinnata plants can absorb fluoride through roots. The absorption is related to the amount of fluoride applied to the soil. There appeared to be a relationship between the amount of fluoride adsorbed and the subsequent growth of the plants. Plants which adsorbed the largest amounts of fluoride had the greatest increase in growth.

  12. Effects of rhizobia and plant growth promoting bacteria inoculation ...

    African Journals Online (AJOL)

    Plant growth promoting rhizobacteria (PGPR) stimulate plant growth by producing phytohormone which enhances the growth and physiological activities of the host plant. Recently, legume bacteria (Rhizobium spp.) have been considered as a PGPR for legume as well as non-legumes and have the potential for growth ...

  13. Strategies for growth: Central and Eastern Europe

    Czech Academy of Sciences Publication Activity Database

    Švejnar, Jan

    -, č. 1 (2006), s. 1-34 Institutional research plan: CEZ:AV0Z70850503 Keywords : transition * economic growth * strategies Subject RIV: AH - Economics http://www.internationalpolicy.umich.edu/policy%20briefs/ Strategies forGrowth09-28-06.pdf

  14. Energy strategy would slow coal's growth, says DOE

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    The National Energy Strategy (NES) recently announced by the Bush Administration would slow the growth in use of coal by hundreds of millions of tons of coal by hundreds of millions of tons after 2000, according to the Department of Energy's (DOE) own figures. If today's policies are continued, coal consumption will nearly triple by 2030. Current annual consumption of more than 900 million tons (19 quadrillion Btus) would rise to 1,550 million tons in 2010 and to nearly 2,600 million tons by 2030. Coal's share of electricity generation, now about 55%, would grow to 75% by 2030 under the current policy base assumptions of the DOE. The NES, however, projects that surge of nuclear power plant construction will stem the growth of coal use. The strategy would still increase coal use, from 19 quadrillion Btus today to about 28 quads in 2010, but to only 32 quads by 2030. By 2030, coal would account for less than 50% of electricity generation under the NES. Total clean coal technologies capacity is substantially lower under the NES scenario case than under the clean coal actions alone. The strategy also contains good news for the coal industry in the short run. It holds out two main goals for coal policy: maintaining coal's competitiveness while meeting environmental, health and safety requirements; and creating a favorable export climate for US coal and coal technology

  15. Soil compaction and growth of woody plants

    Energy Technology Data Exchange (ETDEWEB)

    Kozlowski, T.T. [Univ. of California, Berkeley (United States). Dept. of Environmental Science, Policy and Management

    1999-07-01

    Although soil compaction in the field may benefit or inhibit the growth of plants, the harmful effects are much more common. This paper emphasizes the deleterious effects of predominantly high levels of soil compaction on plant growth and yield. High levels of soil compaction are common in heavily used recreation areas, construction sites, urban areas, timber harvesting sites, fruit orchards, agroforestry systems and tree nurseries. Compaction can occur naturally by settling or slumping of soil or may be induced by tillage tools, heavy machinery, pedestrian traffic, trampling by animals and fire. Compaction typically alters soil structure and hydrology by increasing soil bulk density; breaking down soil aggregates; decreasing soil porosity, aeration and infiltration capacity; and by increasing soil strength, water runoff and soil erosion. Appreciable compaction of soil leads to physiological dysfunctions in plants. Often, but not always, reduced water absorption and leaf water deficits develop. Soil compaction also induces changes in the amounts and balances of growth hormones in plants, especially increases in abscisic acid and ethylene. Absorption of the major mineral nutrients is reduced by compaction of both surface soils and subsoils. The rate of photosynthesis of plants growing in very compacted soil is decreased by both stomatal and non-stomatal inhibition. Total photosynthesis is reduced as a result of smaller leaf areas. As soils become increasingly compacted respiration of roots shifts toward an anaerobic state. Severe soil compaction adversely influences regeneration of forest stands by inhibiting seed germination and growth of seedlings, and by inducing seedling mortality. Growth of woody plants beyond the seedling stage and yields of harvestable plant products also are greatly decreased by soil compaction because of the combined effects of high soil strength, decreased infiltration of water and poor soil aeration, all of which lead to a decreased

  16. Soil compaction and growth of woody plants

    International Nuclear Information System (INIS)

    Kozlowski, T.T.

    1999-01-01

    Although soil compaction in the field may benefit or inhibit the growth of plants, the harmful effects are much more common. This paper emphasizes the deleterious effects of predominantly high levels of soil compaction on plant growth and yield. High levels of soil compaction are common in heavily used recreation areas, construction sites, urban areas, timber harvesting sites, fruit orchards, agroforestry systems and tree nurseries. Compaction can occur naturally by settling or slumping of soil or may be induced by tillage tools, heavy machinery, pedestrian traffic, trampling by animals and fire. Compaction typically alters soil structure and hydrology by increasing soil bulk density; breaking down soil aggregates; decreasing soil porosity, aeration and infiltration capacity; and by increasing soil strength, water runoff and soil erosion. Appreciable compaction of soil leads to physiological dysfunctions in plants. Often, but not always, reduced water absorption and leaf water deficits develop. Soil compaction also induces changes in the amounts and balances of growth hormones in plants, especially increases in abscisic acid and ethylene. Absorption of the major mineral nutrients is reduced by compaction of both surface soils and subsoils. The rate of photosynthesis of plants growing in very compacted soil is decreased by both stomatal and non-stomatal inhibition. Total photosynthesis is reduced as a result of smaller leaf areas. As soils become increasingly compacted respiration of roots shifts toward an anaerobic state. Severe soil compaction adversely influences regeneration of forest stands by inhibiting seed germination and growth of seedlings, and by inducing seedling mortality. Growth of woody plants beyond the seedling stage and yields of harvestable plant products also are greatly decreased by soil compaction because of the combined effects of high soil strength, decreased infiltration of water and poor soil aeration, all of which lead to a decreased

  17. Plant Growth Modeling Using L-System Approach and Its Visualization

    Directory of Open Access Journals (Sweden)

    Atris Suyantohadi

    2011-05-01

    Full Text Available The visualizationof plant growth modeling using computer simulation has rarely been conducted with Lindenmayer System (L-System approach. L-System generally has been used as framework for improving and designing realistic modeling on plant growth. It is one kind of tools for representing plant growth based on grammar sintax and mathematic formulation. This research aimed to design modeling and visualizing plant growth structure generated using L-System. The environment on modeling design used three dimension graphic on standart OpenGL format. The visualization on system design has been developed by some of L-System grammar, and the output graphic on three dimension reflected on plant growth as a virtual plant growth system. Using some of samples on grammar L-System rules for describing of the charaterictics of plant growth, the visualization of structure on plant growth has been resulted and demonstrated.

  18. Inoculating Helianthus annuus (sunflower) grown in zinc and cadmium contaminated soils with plant growth promoting bacteria--effects on phytoremediation strategies.

    Science.gov (United States)

    Marques, Ana P G C; Moreira, Helena; Franco, Albina R; Rangel, António O S S; Castro, Paula M L

    2013-06-01

    Plant growth promoting bacteria (PGPR) may help reducing the toxicity of heavy metals to plants in polluted environments. In this work the effects of inoculating metal resistant and plant growth promoting bacterial strains on the growth of Helianthus annuus grown in Zn and Cd spiked soils were assessed. The PGPR strains Ralstonia eutropha (B1) and Chrysiobacterium humi (B2) reduced losses of weight in metal exposed plants and induced changes in metal bioaccumulation and bioconcentration - with strain B2 decreasing up to 67% Zn accumulation and by 20% Zn bioconcentration factor (BCF) in the shoots, up to 64% Zn uptake and 38% Zn BCF in the roots, and up to 27% Cd uptake and 27% Cd BCF in plant roots. The impact of inoculation on the bacterial communities in the rhizosphere of the plant was also assessed. Bacterial community diversity decreased with increasing levels of metal contamination in the soil, but in rhizosphere soil of plants inoculated with the PGPR strains, a higher bacterial diversity was kept throughout the experimental period. Inoculation of sunflower, particularly with C. humi (B2), appears to be an effective way of enhancing the short term stabilization potential of the plant in metal contaminated land, lowering losses in plant biomass and decreasing aboveground tissue contamination. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Marketing aspects of steady growth business strategy

    OpenAIRE

    GONCHAR V.; KALININ O.

    2015-01-01

    The article analyzed the importance of marketing to achieve steady business growth, the main strategy of internal development and marketing of its level of development, achieving competitive advantage and the main directions of marketing management. The examples of marketing strategies for leading corporations were described. The problems and prospects of the business strategy of extensive growth and diversification were made.

  20. Transgenic plants with enhanced growth characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Unkefer, Pat J.; Anderson, Penelope S.; Knight, Thomas J.

    2018-01-09

    The invention relates to transgenic plants exhibiting dramatically enhanced growth rates, greater seed and fruit/pod yields, earlier and more productive flowering, more efficient nitrogen utilization, increased tolerance to high salt conditions, and increased biomass yields. In one embodiment, transgenic plants engineered to over-express both glutamine phenylpyruvate transaminase (GPT) and glutamine synthetase (GS) are provided. The GPT+GS double-transgenic plants of the invention consistently exhibit enhanced growth characteristics, with T0 generation lines showing an increase in biomass over wild type counterparts of between 50% and 300%. Generations that result from sexual crosses and/or selfing typically perform even better, with some of the double-transgenic plants achieving an astounding four-fold biomass increase over wild type plants.

  1. Transgenic plants with enhanced growth characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Unkefer, Pat J.; Anderson, Penelope S.; Knight, Thomas J.

    2016-09-06

    The invention relates to transgenic plants exhibiting dramatically enhanced growth rates, greater seed and fruit/pod yields, earlier and more productive flowering, more efficient nitrogen utilization, increased tolerance to high salt conditions, and increased biomass yields. In one embodiment, transgenic plants engineered to over-express both glutamine phenylpyruvate transaminase (GPT) and glutamine synthetase (GS) are provided. The GPT+GS double-transgenic plants of the invention consistently exhibit enhanced growth characteristics, with T0 generation lines showing an increase in biomass over wild type counterparts of between 50% and 300%. Generations that result from sexual crosses and/or selfing typically perform even better, with some of the double-transgenic plants achieving an astounding four-fold biomass increase over wild type plants.

  2. Effect of plant-biostimulant on cassava initial growth

    Directory of Open Access Journals (Sweden)

    João Emílio de Souza Magalhães

    2016-04-01

    Full Text Available ABSTRACT Biostimulants are complex substances that promote hormonal balance in plants, favor the genetic potential expression, and enhance growth of shoots and root system. The use of these plant growth promoters in crops can increase quantitatively and qualitatively crop production. Therefore, the aim of this study was to evaluate the effect of a commercial biostimulant on the initial growth of cassava. The experiment was arranged in a 2 x 5 factorial design, corresponding to two cassava cultivars (Cacau-UFV and Coimbra and five biostimulant concentrations (0, 4, 8, 12 and 16 mL L-1. At 90 days after planting, the characteristics leaf area, plant height, stem diameter, leaf number, total dry matter and dry matter of roots, stems and leaves were evaluated. The biostimulant promoted linear increases in plant height, leaf number, leaf area, total dry matter, dry matter of stems, leaves and roots. The cultivar Cacau-UFV had a higher growth rate than the cultivar Coimbra. The growth promoter stimulated the early growth of the cassava crop.

  3. Analysing growth and development of plants jointly using developmental growth stages.

    Science.gov (United States)

    Dambreville, Anaëlle; Lauri, Pierre-Éric; Normand, Frédéric; Guédon, Yann

    2015-01-01

    Plant growth, the increase of organ dimensions over time, and development, the change in plant structure, are often studied as two separate processes. However, there is structural and functional evidence that these two processes are strongly related. The aim of this study was to investigate the co-ordination between growth and development using mango trees, which have well-defined developmental stages. Developmental stages, determined in an expert way, and organ sizes, determined from objective measurements, were collected during the vegetative growth and flowering phases of two cultivars of mango, Mangifera indica. For a given cultivar and growth unit type (either vegetative or flowering), a multistage model based on absolute growth rate sequences deduced from the measurements was first built, and then growth stages deduced from the model were compared with developmental stages. Strong matches were obtained between growth stages and developmental stages, leading to a consistent definition of integrative developmental growth stages. The growth stages highlighted growth asynchronisms between two topologically connected organs, namely the vegetative axis and its leaves. Integrative developmental growth stages emphasize that developmental stages are closely related to organ growth rates. The results are discussed in terms of the possible physiological processes underlying these stages, including plant hydraulics, biomechanics and carbohydrate partitioning. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Understanding the molecular basis of plant growth promotional effect of Pseudomonas fluorescens on rice through protein profiling.

    Science.gov (United States)

    Kandasamy, Saveetha; Loganathan, Karthiba; Muthuraj, Raveendran; Duraisamy, Saravanakumar; Seetharaman, Suresh; Thiruvengadam, Raguchander; Ponnusamy, Balasubramanian; Ramasamy, Samiyappan

    2009-12-24

    Plant Growth Promoting Rhizobacteria (PGPR), Pseudomonas fluorescens strain KH-1 was found to exhibit plant growth promotional activity in rice under both in-vitro and in-vivo conditions. But the mechanism underlying such promotional activity of P. fluorescens is not yet understood clearly. In this study, efforts were made to elucidate the molecular responses of rice plants to P. fluorescens treatment through protein profiling. Two-dimensional polyacrylamide gel electrophoresis strategy was adopted to identify the PGPR responsive proteins and the differentially expressed proteins were analyzed by mass spectrometry. Priming of P. fluorescens, 23 different proteins found to be differentially expressed in rice leaf sheaths and MS analysis revealed the differential expression of some important proteins namely putative p23 co-chaperone, Thioredoxin h- rice, Ribulose-bisphosphate carboxylase large chain precursor, Nucleotide diPhosphate kinase, Proteosome sub unit protein and putative glutathione S-transferase protein. Functional analyses of the differential proteins were reported to be directly or indirectly involved in growth promotion in plants. Thus, this study confirms the primary role of PGPR strain KH-1 in rice plant growth promotion.

  5. Mechanisms and applications of plant growth promoting rhizobacteria: Current perspective

    Directory of Open Access Journals (Sweden)

    Munees Ahemad

    2014-01-01

    Full Text Available Plant growth promoting rhizobacteria are the soil bacteria inhabiting around/on the root surface and are directly or indirectly involved in promoting plant growth and development via production and secretion of various regulatory chemicals in the vicinity of rhizosphere. Generally, plant growth promoting rhizobacteria facilitate the plant growth directly by either assisting in resource acquisition (nitrogen, phosphorus and essential minerals or modulating plant hormone levels, or indirectly by decreasing the inhibitory effects of various pathogens on plant growth and development in the forms of biocontrol agents. Various studies have documented the increased health and productivity of different plant species by the application of plant growth promoting rhizobacteria under both normal and stressed conditions. The plant-beneficial rhizobacteria may decrease the global dependence on hazardous agricultural chemicals which destabilize the agro-ecosystems. This review accentuates the perception of the rhizosphere and plant growth promoting rhizobacteria under the current perspectives. Further, explicit outlooks on the different mechanisms of rhizobacteria mediated plant growth promotion have been described in detail with the recent development and research. Finally, the latest paradigms of applicability of these beneficial rhizobacteria in different agro-ecosystems have been presented comprehensively under both normal and stress conditions to highlight the recent trends with the aim to develop future insights.

  6. Prospecting cyanobacterial formulations as plant-growth-promoting ...

    African Journals Online (AJOL)

    Cyanobacteria represent environment-friendly inputs that can lead to savings of nitrogenous fertilisers, in addition to improving plant growth and soil fertility. The present investigation aimed to evaluate the potential of cyanobacteria inoculants as nutrient-management and plant-growth-promoting options for maize hybrids, ...

  7. Plant growth promotion and Penicillium citrinum

    Directory of Open Access Journals (Sweden)

    Choo Yeon-Sik

    2008-12-01

    Full Text Available Abstract Background Endophytic fungi are known plant symbionts. They produce a variety of beneficial metabolites for plant growth and survival, as well as defend their hosts from attack of certain pathogens. Coastal dunes are nutrient deficient and offer harsh, saline environment for the existing flora and fauna. Endophytic fungi may play an important role in plant survival by enhancing nutrient uptake and producing growth-promoting metabolites such as gibberellins and auxins. We screened roots of Ixeris repenes (L. A. Gray, a common dune plant, for the isolation of gibberellin secreting endophytic fungi. Results We isolated 15 endophytic fungi from the roots of Ixeris repenes and screened them for growth promoting secondary metabolites. The fungal isolate IR-3-3 gave maximum plant growth when applied to waito-c rice and Atriplex gemelinii seedlings. Analysis of the culture filtrate of IR-3-3 showed the presence of physiologically active gibberellins, GA1, GA3, GA4 and GA7 (1.95 ng/ml, 3.83 ng/ml, 6.03 ng/ml and 2.35 ng/ml, respectively along with other physiologically inactive GA5, GA9, GA12, GA15, GA19, GA20 and, GA24. The plant growth promotion and gibberellin producing capacity of IR-3-3 was much higher than the wild type Gibberella fujikuroi, which was taken as control during present study. GA5, a precursor of bioactive GA3 was reported for the first time in fungi. The fungal isolate IR-3-3 was identified as a new strain of Penicillium citrinum (named as P. citrinum KACC43900 through phylogenetic analysis of 18S rDNA sequence. Conclusion Isolation of new strain of Penicillium citrinum from the sand dune flora is interesting as information on the presence of Pencillium species in coastal sand dunes is limited. The plant growth promoting ability of this fungal strain may help in conservation and revegetation of the rapidly eroding sand dune flora. Penicillium citrinum is already known for producing mycotoxin citrinin and cellulose digesting

  8. New auxin analogs with growth-promoting effects in intact plants reveal a chemical strategy to improve hormone delivery.

    Science.gov (United States)

    Savaldi-Goldstein, Sigal; Baiga, Thomas J; Pojer, Florence; Dabi, Tsegeye; Butterfield, Cristina; Parry, Geraint; Santner, Aaron; Dharmasiri, Nihal; Tao, Yi; Estelle, Mark; Noel, Joseph P; Chory, Joanne

    2008-09-30

    Plant growth depends on the integration of environmental cues and phytohormone-signaling pathways. During seedling emergence, elongation of the embryonic stem (hypocotyl) serves as a readout for light and hormone-dependent responses. We screened 10,000 chemicals provided exogenously to light-grown seedlings and identified 100 compounds that promote hypocotyl elongation. Notably, one subset of these chemicals shares structural characteristics with the synthetic auxins, 2,4-dichlorophenoxyacetic acid (2,4-D), and 1-naphthaleneacetic acid (1-NAA); however, traditional auxins (e.g., indole-3-acetic acid [IAA], 2,4-D, 1-NAA) have no effect on hypocotyl elongation. We show that the new compounds act as "proauxins" akin to prodrugs. Our data suggest that these compounds diffuse efficiently to the hypocotyls, where they undergo cleavage at varying rates, releasing functional auxins. To investigate this principle, we applied a masking strategy and designed a pro-2,4-D. Unlike 2,4-D alone, this pro-2,4-D enhanced hypocotyl elongation. We further demonstrated the utility of the proauxins by characterizing auxin responses in light-grown hypocotyls of several auxin receptor mutants. These new compounds thus provide experimental access to a tissue previously inaccessible to exogenous application of auxins. Our studies exemplify the combined power of chemical genetics and biochemical analyses for discovering and refining prohormone analogs with selective activity in specific plant tissues. In addition to the utility of these compounds for addressing questions related to auxin and light-signaling interactions, one can envision using these simple principles to study other plant hormone and small molecule responses in temporally and spatially controlled ways.

  9. Foreign acquisition, plant survival, and employment growth

    DEFF Research Database (Denmark)

    Bandick, Roger; Görg, Holger

    This paper analyses the effect of foreign acquisition on survival probability and employment growth of target plant using data on Swedish manufacturing plants during the period 1993-2002.  An improvement over previous studies is that we take into account firm level heterogeneity by separating...... the lifetime of the acquired plants only if the plant was an exporter.  The effect differs depending on whether the acquisition is horizontal or vertical.  We also find robust positive employment growth effects only for exporters, and only if the takeover is vertical, not horizontal....

  10. Plant Growth Promoting Rhizobacteria

    Indian Academy of Sciences (India)

    IAS Admin

    known to improve plant growth in many ways when compared to ... roles in agricultural productivity. ... Sustainable agriculture: Sustainable agriculture involves the successful management of agricultural re- ... For the first time Kloepper et al.

  11. Plant growth and gas balance in a plant and mushroom cultivation system

    Science.gov (United States)

    Kitaya, Y.; Tani, A.; Kiyota, M.; Aiga, I.

    1994-11-01

    In order to obtain basic data for construction of a plant cultivation system incorporating a mushroom cultivation subsystem in the CELSS, plant growth and atmospheric CO2 balance in the system were investigated. The plant growth was promoted by a high level of CO2 which resulted from the respiration of the mushroom mycelium in the system. The atmospheric CO2 concentration inside the system changed significantly due to the slight change in the net photosynthetic rate of plants and/or the respiration rate of the mushroom when the plant cultivation system combined directly with the mushroom cultivation subsystem.

  12. The Response Strategy of Maize, Pea and Broad Bean Plants to Different Osmotic Potential Stress

    Directory of Open Access Journals (Sweden)

    Hamdia M. Abd El-Samad

    2013-08-01

    Full Text Available This investigation was conducted to study the tolerance strategy of maize, broad bean and pea plants to salinity stress with exogenous applications of proline or phenylalanine on seed germination and seedlings growth. From the results obtained, it can be observed that osmotic stress affected adversely the rate of germination in maize, broad bean and pea plants. The excessive inhibition was more prominent at higher concentration of NaCl. The seeds and grains tested were exhibited some differential responses to salinity, in a manner that the inhibitory effect of salinity on seed germination ran in the order, maize higher than broad bean and the later was higher than pea plant. Treatment with proline or phenylalanine (100 ppm significantly increased these seed germination and seedlings growth characteristics even at lowest salinity level tested.

  13. Inoculation of Schizolobium parahyba with mycorrhizal fungi and plant growth-promoting rhizobacteria increases wood yield under field conditions

    Directory of Open Access Journals (Sweden)

    Martha Viviana Torres Cely

    2016-11-01

    Full Text Available Schizolobium parahyba var. amazonicum (Huber ex Ducke occurs naturally in the Brazilian Amazon. Currently, it is being planted extensively because of its fast growth and excellent use in forestry. Consequently, there is great interest in new strategies to increase wood production. The interaction between soil microorganisms and plants, specifically in the roots, provides essential nutrients for plant growth. These interactions can have growth-promoting effects. In this way, this study assessed the effect of the inoculation with arbuscular mycorrhizal fungi (AMF and plant growth-promoting rhizobacteria (PGPR on growth of S. parahyba var. amazonicum under field conditions. We used two native species of arbuscular mycorrhizal fungi, Claroideoglomus etunicatum (Ce and Acaulospora sp. (Ac; two native strains of Rhizobium sp. (Rh1 and Rh2; and a non-native strain of Burkholderia sp. Different combinations of microorganisms were supplemented with chemical fertilizers (doses D1 and D2 in two planting methods, seed sowing and seedling planting. In seed sowing, the results showed that treatments with Ce/Rh1/Fertilizer D2 and Ac/No PGPR/Fertilizer D2 increased wood yield. In seedling planting, two combinations (Ac/Rh2/Fertilizer D1 and Ac/Rh1/Fertilizer D1 were more effective in increasing seedling growth. In these experiments, inoculation with AMF and PGPR increased wood yield by about 20% compared to the application of fertilizer alone.

  14. Inoculation of Schizolobium parahyba with Mycorrhizal Fungi and Plant Growth-Promoting Rhizobacteria Increases Wood Yield under Field Conditions.

    Science.gov (United States)

    Cely, Martha V T; Siviero, Marco A; Emiliano, Janaina; Spago, Flávia R; Freitas, Vanessa F; Barazetti, André R; Goya, Erika T; Lamberti, Gustavo de Souza; Dos Santos, Igor M O; De Oliveira, Admilton G; Andrade, Galdino

    2016-01-01

    Schizolobium parahyba var. amazonicum (Huber ex Ducke) occurs naturally in the Brazilian Amazon. Currently, it is being planted extensively because of its fast growth and excellent use in forestry. Consequently, there is great interest in new strategies to increase wood production. The interaction between soil microorganisms and plants, specifically in the roots, provides essential nutrients for plant growth. These interactions can have growth-promoting effects. In this way, this study assessed the effect of the inoculation with arbuscular mycorrhizal fungi (AMF) and plant growth-promoting rhizobacteria (PGPR) on growth of S. parahyba var. amazonicum under field conditions. We used two native species of arbuscular mycorrhizal fungi, Claroideoglomus etunicatum (Ce), and Acaulospora sp. (Ac); two native strains of Rhizobium sp. (Rh1 and Rh2); and a non-native strain of Burkholderia sp. Different combinations of microorganisms were supplemented with chemical fertilizers (doses D1 and D2) in two planting methods, seed sowing and seedling planting. In seed sowing, the results showed that treatments with Ce/Rh1/Fertilizer D2 and Ac/No PGPR/Fertilizer D2 increased wood yield. In seedling planting, two combinations (Ac/Rh2/Fertilizer D1 and Ac/Rh1/Fertilizer D1) were more effective in increasing seedling growth. In these experiments, inoculation with AMF and PGPR increased wood yield by about 20% compared to the application of fertilizer alone.

  15. Plant Growth Promoting Rhizobacteria in Amelioration of Salinity Stress: A Systems Biology Perspective

    Directory of Open Access Journals (Sweden)

    Gayathri Ilangumaran

    2017-10-01

    Full Text Available Salinity affects plant growth and is a major abiotic stress that limits crop productivity. It is well-understood that environmental adaptations and genetic traits regulate salinity tolerance in plants, but imparting the knowledge gained towards crop improvement remain arduous. Harnessing the potential of beneficial microorganisms present in the rhizosphere is an alternative strategy for improving plant stress tolerance. This review intends to elucidate the understanding of salinity tolerance mechanisms attributed by plant growth promoting rhizobacteria (PGPR. Recent advances in molecular studies have yielded insights into the signaling networks of plant–microbe interactions that contribute to salt tolerance. The beneficial effects of PGPR involve boosting key physiological processes, including water and nutrient uptake, photosynthesis, and source-sink relationships that promote growth and development. The regulation of osmotic balance and ion homeostasis by PGPR are conducted through modulation of phytohormone status, gene expression, protein function, and metabolite synthesis in plants. As a result, improved antioxidant activity, osmolyte accumulation, proton transport machinery, salt compartmentalization, and nutrient status reduce osmotic stress and ion toxicity. Furthermore, in addition to indole-3-acetic acid and 1-aminocyclopropane-1-carboxylic acid deaminase biosynthesis, other extracellular secretions of the rhizobacteria function as signaling molecules and elicit stress responsive pathways. Application of PGPR inoculants is a promising measure to combat salinity in agricultural fields, thereby increasing global food production.

  16. What Is Green Growth Strategy for Government Link Company?

    Science.gov (United States)

    Jamilah Asha'ari, Maryam; Daud, Salina; Hassan, Hasmaizan

    2016-03-01

    Disasters around the world are very extreme because of the global warming and climate change. Malaysia firms have to play their role in handling the challenging of environmental problems in order to sustain. The feature of the new strategy which is green growth strategy has been identified. The study focuses on the features of the green growth strategy which discuss on the keys to sustaining the strategy, marketing emphasis, production emphasis, product line, basis of competitive advantage and strategic target. Business had contributed to the industrialisation era positively or negatively and therefore there is a must for business people to use the best strategy in reducing the environmental risks. By 2020, Malaysia will achieve the target in becoming an advanced economy by applying the right strategy. The objective of this paper is to propose a feature for new strategy known as green growth strategy. Future study is to propose to conduct an empirical analysis to confirm the green growth strategy features.

  17. by recycled subirrigational supply of plant growth retardants

    African Journals Online (AJOL)

    STORAGESEVER

    2008-05-16

    May 16, 2008 ... an ebb and flow system on the growth and flowering of kalanchoe cultivar 'Gold Strike' was examined. Plants potted in 10 cm .... photoperiod during the first six weeks after pinching. .... stage and adverse influences on overall growth of the plants. ..... retardants on the growth and flowering in poinsettia. RDA.

  18. Evaluation of antagonistic and plant growth promoting activities of chitinolytic endophytic actinomycetes associated with medicinal plants against Sclerotium rolfsii in chickpea.

    Science.gov (United States)

    Singh, S P; Gaur, R

    2016-08-01

    To evaluate the potential of chitinolytic endophytic Actinomycetes isolated from medicinal plants in order to diminish the collar rot infestation induced by Sclerotium rolfsii in chickpea. Sixty-eight chitinolytic endophytic Actinomycetes were recovered from various medicinal plants and evaluated for their chitinase activity. Among these isolates, 12 were screened for their plant growth promoting abilities and antagonistic potential against Sc. rolfsii. Further, these isolates were validated in vivo for their ability to protect chickpea against Sc. rolfsii infestation under greenhouse conditions. The isolates significantly (P plant mortality (42-75%) of chickpea. On the basis of 16S rDNA profiling, the selected antagonistic strains were identified as Streptomyces diastaticus, Streptomyces fradiae, Streptomyces olivochromogenes, Streptomyces collinus, Streptomyces ossamyceticus and Streptomyces griseus. This study is the first report of the isolation of endophytic Actinomycetes from various medicinal plants having antagonistic and plant growth promoting abilities. The isolated species showed potential for controlling collar rot disease on chickpea and could be useful in integrated control against diverse soil borne plant pathogens. Our investigation suggests that endophytic Actinomycetes associated with medicinal plants can be used as bioinoculants for developing safe, efficacious and environment-friendly biocontrol strategies in the near future. © 2016 The Society for Applied Microbiology.

  19. Spiral Growth in Plants: Models and Simulations

    Science.gov (United States)

    Allen, Bradford D.

    2004-01-01

    The analysis and simulation of spiral growth in plants integrates algebra and trigonometry in a botanical setting. When the ideas presented here are used in a mathematics classroom/computer lab, students can better understand how basic assumptions about plant growth lead to the golden ratio and how the use of circular functions leads to accurate…

  20. Isolation of Pantoea ananatis from sugarcane and characterization of its potential for plant growth promotion.

    Science.gov (United States)

    da Silva, J F; Barbosa, R R; de Souza, A N; da Motta, O V; Teixeira, G N; Carvalho, V S; de Souza, A L S R; de Souza Filho, G A

    2015-11-30

    Each year, approximately 170 million metric tons of chemical fertilizer are consumed by global agriculture. Furthermore, some chemical fertilizers contain toxic by-products and their long-term use may contaminate groundwater, lakes, and rivers. The use of plant growth-promoting bacteria may be a cost-effective strategy for partially replacing conventional chemical fertilizers, and may become an integrated plant nutrient solution for sustainable crop production. The main direct bacteria-activated mechanisms of plant growth promotion are based on improvement of nutrient acquisition, siderophore biosynthesis, nitrogen fixation, and hormonal stimulation. The aim of this study was to isolate and identify bacteria with growth-promoting activities from sugarcane. We extracted the bacterial isolate SCB4789F-1 from sugarcane leaves and characterized it with regard to its profile of growth-promoting activities, including its ability to colonize Arabidopsis thaliana. Based on its biochemical characteristics and 16S rDNA sequence analysis, this isolate was identified as Pantoea ananatis. The bacteria were efficient at phosphate and zinc solubilization, and production of siderophores and indole-3-acetic acid in vitro. The isolate was characterized by Gram staining, resistance to antibiotics, and use of carbon sources. This is the first report on zinc solubilization in vitro by this bacterium, and on plant growth promotion following its inoculation into A. thaliana. The beneficial effects to plants of this bacterium justify future analysis of inoculation of economically relevant crops.

  1. Understanding the molecular basis of plant growth promotional effect of Pseudomonas fluorescens on rice through protein profiling

    Directory of Open Access Journals (Sweden)

    Thiruvengadam Raguchander

    2009-12-01

    Full Text Available Abstract Background Plant Growth Promoting Rhizobacteria (PGPR, Pseudomonas fluorescens strain KH-1 was found to exhibit plant growth promotional activity in rice under both in-vitro and in-vivo conditions. But the mechanism underlying such promotional activity of P. fluorescens is not yet understood clearly. In this study, efforts were made to elucidate the molecular responses of rice plants to P. fluorescens treatment through protein profiling. Two-dimensional polyacrylamide gel electrophoresis strategy was adopted to identify the PGPR responsive proteins and the differentially expressed proteins were analyzed by mass spectrometry. Results Priming of P. fluorescens, 23 different proteins found to be differentially expressed in rice leaf sheaths and MS analysis revealed the differential expression of some important proteins namely putative p23 co-chaperone, Thioredoxin h- rice, Ribulose-bisphosphate carboxylase large chain precursor, Nucleotide diPhosphate kinase, Proteosome sub unit protein and putative glutathione S-transferase protein. Conclusion Functional analyses of the differential proteins were reported to be directly or indirectly involved in growth promotion in plants. Thus, this study confirms the primary role of PGPR strain KH-1 in rice plant growth promotion.

  2. Nuclear power plant outage optimisation strategy

    International Nuclear Information System (INIS)

    2002-10-01

    Competitive environment for electricity generation has significant implications for nuclear power plant operations, including among others the need of efficient use of resources, effective management of plant activities such as on-line maintenance and outages. Nuclear power plant outage management is a key factor for good, safe and economic nuclear power plant performance which involves many aspects: plant policy, co-ordination of available resources, nuclear safety, regulatory and technical requirements and, all activities and work hazards, before and during the outage. This technical publication aims to communicate these practices in a way they can be used by operators and utilities in the Member States of the IAEA. It intends to give guidance to outage managers, operating staff and to the local industry on planning aspects, as well as examples and strategies experienced from current plants in operation on the optimization of outage period. This report discusses the plant outage strategy and how this strategy is actually implemented. The main areas identified as most important for outage optimization by the utilities and government organizations participating in this report are: organization and management; outage planning and preparation, outage execution, safety outage review, and counter measures to avoid extension of outages and to easier the work in forced outages. This report was based on discussions and findings by the authors of the annexes and the participants of an Advisory Group Meeting on Determinant Causes for Reducing Outage Duration held in June 1999 in Vienna. The report presents the consensus of these experts regarding best common or individual good practices that can be used at nuclear power plants with the aim to optimize

  3. 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 ...

  4. Interfrm Cooperation Strategy of Hyper-Growth and Stable-Growth ICT Firms in Sweden

    Directory of Open Access Journals (Sweden)

    Monika Golonka

    2017-01-01

    Full Text Available Purpose: The main purpose of this study was to compare the phenomenon of interfrm cooperation strategy in both hyper-growth, and stable-growth knowledge and technology–intensive frms, in a country characterized by a high level of generalized trust: Sweden. Methodology: Qualitative methods were incorporated: direct semistructured interviews with top managers in 13 ICT frms (8 hyper-growth and 5 stable-growth, analyzis of reports, corporate websites and press releases. Furthermore, interviews in 3 expert frms in the industry were conducted, facilitating interfrm cooperation. Conclusions: There were signifcant differences in interfrm cooperation strategy in two distinguished groups of the frms: hyper-growth, and stable-growth. Managers’ individual approaches to uncertainty, strategy and cooperation might be more important than institutional settings. The ICT frms operate in a constantly changing global environment and local context seems to have only a minor impact on the rules of the game in the industry. Research limitations: This study was a qualitative explorative approach as an introduction to further empirical research. Originality: The study presents an interfrm cooperation phenomenon incorporating different perspectives and settings. It contributes to alliance portfolio literature (forming and managing of alliance portfolio in a different context/country/industry, and enhances understanding of frm strategies characterized by different growth rates.

  5. Increasing rice plant growth by Trichoderma sp.

    Science.gov (United States)

    Doni, Febri; Isahak, Anizan; Zain, Che Radziah Che Mohd; Sulaiman, Norela; Fathurahman, F.; Zain, Wan Nur Syazana Wan Mohd.; Kadhimi, Ahsan A.; Alhasnawi, Arshad Naji; Anhar, Azwir; Yusoff, Wan Mohtar Wan

    2016-11-01

    Trichoderma sp. is a plant growth promoting fungi in many crops. Initial observation on the ability to enhance rice germination and vigor have been reported. In this study, the effectiveness of a local isolate Trichoderma asprellum SL2 to enhance rice seedling growth was assessed experimentally under greenhouse condition using a completely randomized design. Results showed that inoculation of rice plants with Trichoderma asprellum SL2 significantly increase rice plants height, root length, wet weight, leaf number and biomass compared to untreated rice plants (control). The result of this study can serve as a reference for further work on the application of beneficial microorganisms to enhance rice production.

  6. Foreign acquisition, plant survival, and employment growth

    DEFF Research Database (Denmark)

    Bandick, Roger; Görg, Holger

    2010-01-01

    This paper analyzes the effect of foreign acquisition on survival and employment growth of targets using data on Swedish manufacturing plants.We separate targeted plants into those within Swedish MNEs, Swedish exporting non-MNEs, and purely domestic firms. The results, controlling for possible...... acquisitions. We find robust positive employment growth effects only for exporters and only if the takeover is vertical....

  7. Relationship between expansion strategy and growth of charismatic ...

    African Journals Online (AJOL)

    ... vital strategy being prayer. Other important growth strategies were: evangelism, type of sermon, membership welfare and service structure. The Franchise/ Business model was found to yield better church growth than the Episcopal model. Keywords: Franchise, Business model, Episcopal model, charismatic churches ...

  8. Engineered nanomaterials for plant growth and development: A perspective analysis.

    Science.gov (United States)

    Verma, Sandeep Kumar; Das, Ashok Kumar; Patel, Manoj Kumar; Shah, Ashish; Kumar, Vinay; Gantait, Saikat

    2018-07-15

    With the overwhelmingly rapid advancement in the field of nanotechnology, the engineered nanomaterials (ENMs) have been extensively used in various areas of the plant system, including quality improvement, growth and nutritional value enhancement, gene preservation etc. There are several recent reports on the ENMs' influence on growth enhancements, growth inhibition as well as certain toxic impacts on plant. However, translocation, growth responses and stress modulation mechanisms of ENMs in the plant systems call for better and in-depth understanding. Herein, we are presenting a comprehensive and critical account of different types of ENMs, their applications and their positive, negative and null impacts on physiological and molecular aspects of plant growth, development and stress responses. Recent reports revealed mixed effects on plants, ranging from enhanced crop yield, epi/genetic alterations, and phytotoxicity, resulting from the ENMs' exposure. Creditable research in recent years has revealed that the effects of ENMs on plants are species specific and are variable among plant species. ENM exposures are reported to trigger free radical formation, responsive scavenging, and antioxidant armories in the exposed plants. The ENMs are also reported to induce aberrant expressions of microRNAs, the key post-transcriptional regulators of plant growth, development and stress-responses of plants. However, these modulations, if judiciously done, may lead to improved plant growth and yield. A better understanding of the interactions between ENMs and plant responses, including their uptake transport, internalization, and activity, could revolutionize crop production through increased disease resistance, nutrient utilization, and crop yield. Therefore, in this review, we are presenting a critical account of the different selected ENMs, their uptake by the plants, their positive/negative impacts on plant growth and development, along with the resultant ENM-responsive post

  9. Graphene quantum dots as enhanced plant growth regulators: effects on coriander and garlic plants.

    Science.gov (United States)

    Chakravarty, Disha; Erande, Manisha B; Late, Dattatray J

    2015-10-01

    We report investigations on the use of graphene quantum dots for growth enhancement in coriander (Coriandrum sativam L.) and garlic (Allium sativum) plants. The as-received seeds of coriander and garlic were treated with 0.2 mg mL(-1) of graphene quantum dots for 3 h before planting. Graphene quantum dots enhanced the growth rate in coriander and garlic plants, including leaves, roots, shoots, flowers and fruits, when the seeds were treated with graphene quantum dots. Our investigations open up the opportunity to use graphene quantum dots as plant growth regulators that can be used in a variety of other food plants for high yield. © 2015 Society of Chemical Industry.

  10. Leaf and life history traits predict plant growth in a green roof ecosystem.

    Directory of Open Access Journals (Sweden)

    Jeremy Lundholm

    Full Text Available Green roof ecosystems are constructed to provide services such as stormwater retention and urban temperature reductions. Green roofs with shallow growing media represent stressful conditions for plant survival, thus plants that survive and grow are important for maximizing economic and ecological benefits. While field trials are essential for selecting appropriate green roof plants, we wanted to determine whether plant leaf traits could predict changes in abundance (growth to provide a more general framework for plant selection. We quantified leaf traits and derived life-history traits (Grime's C-S-R strategies for 13 species used in a four-year green roof experiment involving five plant life forms. Changes in canopy density in monocultures and mixtures containing one to five life forms were determined and related to plant traits using multiple regression. We expected traits related to stress-tolerance would characterize the species that best grew in this relatively harsh setting. While all species survived to the end of the experiment, canopy species diversity in mixture treatments was usually much lower than originally planted. Most species grew slower in mixture compared to monoculture, suggesting that interspecific competition reduced canopy diversity. Species dominant in mixture treatments tended to be fast-growing ruderals and included both native and non-native species. Specific leaf area was a consistently strong predictor of final biomass and the change in abundance in both monoculture and mixture treatments. Some species in contrasting life-form groups showed compensatory dynamics, suggesting that life-form mixtures can maximize resilience of cover and biomass in the face of environmental fluctuations. This study confirms that plant traits can be used to predict growth performance in green roof ecosystems. While rapid canopy growth is desirable for green roofs, maintenance of species diversity may require engineering of conditions that

  11. Leaf and life history traits predict plant growth in a green roof ecosystem.

    Science.gov (United States)

    Lundholm, Jeremy; Heim, Amy; Tran, Stephanie; Smith, Tyler

    2014-01-01

    Green roof ecosystems are constructed to provide services such as stormwater retention and urban temperature reductions. Green roofs with shallow growing media represent stressful conditions for plant survival, thus plants that survive and grow are important for maximizing economic and ecological benefits. While field trials are essential for selecting appropriate green roof plants, we wanted to determine whether plant leaf traits could predict changes in abundance (growth) to provide a more general framework for plant selection. We quantified leaf traits and derived life-history traits (Grime's C-S-R strategies) for 13 species used in a four-year green roof experiment involving five plant life forms. Changes in canopy density in monocultures and mixtures containing one to five life forms were determined and related to plant traits using multiple regression. We expected traits related to stress-tolerance would characterize the species that best grew in this relatively harsh setting. While all species survived to the end of the experiment, canopy species diversity in mixture treatments was usually much lower than originally planted. Most species grew slower in mixture compared to monoculture, suggesting that interspecific competition reduced canopy diversity. Species dominant in mixture treatments tended to be fast-growing ruderals and included both native and non-native species. Specific leaf area was a consistently strong predictor of final biomass and the change in abundance in both monoculture and mixture treatments. Some species in contrasting life-form groups showed compensatory dynamics, suggesting that life-form mixtures can maximize resilience of cover and biomass in the face of environmental fluctuations. This study confirms that plant traits can be used to predict growth performance in green roof ecosystems. While rapid canopy growth is desirable for green roofs, maintenance of species diversity may require engineering of conditions that favor less

  12. Portraying mechanics of plant growth promoting rhizobacteria (PGPR: A review

    Directory of Open Access Journals (Sweden)

    Dweipayan Goswami

    2016-12-01

    Full Text Available Population growth and increase in food requirement is the global problem. It is inevitable to introduce new practices that help to increase agricultural productivity. Use of plant growth promoting rhizobacteria (PGPR has shown potentials to be a promising technique in the practice of sustainable agriculture. A group of natural soil microbial flora acquire dwelling in the rhizosphere and on the surface of the plant roots which impose beneficial effect on the overall well-being of the plant are categorized as PGPR. Researchers are actively involved in understanding plant growth promoting mechanics employed by PGPR. Broadly, these are divided into direct and indirect mechanics. Any mechanism that directly enhances plant growth either by providing nutrients or by producing growth regulators are portrayed as direct mechanics. Whereas, any mechanisms that protects plant from acquiring infections (biotic stress or helps plant to grow healthily under environmental stresses (abiotic stress are considered indirect mechanics. This review is focused to describe cogent mechanics employed by PGPR that assists plant to sustain healthy growth. Also, we emphasized on the PGPR-based products which have been commercially developed exploiting these mechanics of PGPR.

  13. Enterococcus faecium LKE12 Cell-Free Extract Accelerates Host Plant Growth via Gibberellin and Indole-3-Acetic Acid Secretion.

    Science.gov (United States)

    Lee, Ko-Eun; Radhakrishnan, Ramalingam; Kang, Sang-Mo; You, Young-Hyun; Joo, Gil-Jae; Lee, In-Jung; Ko, Jae-Hwan; Kim, Jin-Ho

    2015-09-01

    The use of microbial extracts containing plant hormones is a promising technique to improve crop growth. Little is known about the effect of bacterial cell-free extracts on plant growth promotion. This study, based on phytohormonal analyses, aimed at exploring the potential mechanisms by which Enterococcus faecium LKE12 enhances plant growth in oriental melon. A bacterial strain, LKE12, was isolated from soil, and further identified as E. faecium by 16S rDNA sequencing and phylogenetic analysis. The plant growth-promoting ability of an LKE12 bacterial culture was tested in a gibberellin (GA)-deficient rice dwarf mutant (waito-C) and a normal GA biosynthesis rice cultivar (Hwayongbyeo). E. faecium LKE12 significantly improved the length and biomass of rice shoots in both normal and dwarf cultivars through the secretion of an array of gibberellins (GA1, GA3, GA7, GA8, GA9, GA12, GA19, GA20, GA24, and GA53), as well as indole-3-acetic acid (IAA). To the best of our knowledge, this is the first study indicating that E. faecium can produce GAs. Increases in shoot and root lengths, plant fresh weight, and chlorophyll content promoted by E. faecium LKE12 and its cell-free extract inoculated in oriental melon plants revealed a favorable interaction of E. faecium LKE12 with plants. Higher plant growth rates and nutrient contents of magnesium, calcium, sodium, iron, manganese, silicon, zinc, and nitrogen were found in cell-free extract-treated plants than in control plants. The results of the current study suggest that E. faecium LKE12 promotes plant growth by producing GAs and IAA; interestingly, the exogenous application of its cell-free culture extract can be a potential strategy to accelerate plant growth.

  14. Effect of plant growth-promoting bacteria on the growth and fructan production of Agave americana L.

    Directory of Open Access Journals (Sweden)

    Neyser De La Torre-Ruiz

    Full Text Available ABSTRACT The effect of plant growth-promoting bacteria inoculation on plant growth and the sugar content in Agave americana was assessed. The bacterial strains ACO-34A, ACO-40, and ACO-140, isolated from the A. americana rhizosphere, were selected for this study to evaluate their phenotypic and genotypic characteristics. The three bacterial strains were evaluated via plant inoculation assays, and Azospirillum brasilense Cd served as a control strain. Phylogenetic analysis based on the 16S rRNA gene showed that strains ACO-34A, ACO-40 and ACO-140 were Rhizobium daejeonense, Acinetobacter calcoaceticus and Pseudomonas mosselii, respectively. All of the strains were able to synthesize indole-3-acetic acid (IAA, solubilize phosphate, and had nitrogenase activity. Inoculation using the plant growth-promoting bacteria strains had a significant effect (p < 0.05 on plant growth and the sugar content of A. americana, showing that these native plant growth-promoting bacteria are a practical, simple, and efficient alternative to promote the growth of agave plants with proper biological characteristics for agroindustrial and biotechnological use and to increase the sugar content in this agave species.

  15. Efficiency of plant growth-promoting rhizobacteria (PGPR) for the ...

    African Journals Online (AJOL)

    Plant growth-promoting rhizobacteria (PGPR) are beneficial bacteria that colonize plant roots and enhance plant growth by a wide variety of mechanisms. The use of PGPR is steadily increasing in agriculture and offers an attractive way to replace chemical fertilizers, pesticides, and supplements. Here, we have isolated and ...

  16. Expert System Control of Plant Growth in an Enclosed Space

    Science.gov (United States)

    May, George; Lanoue, Mark; Bathel, Matthew; Ryan, Robert E.

    2008-01-01

    The Expert System is an enclosed, controlled environment for growing plants, which incorporates a computerized, knowledge-based software program that is designed to capture the knowledge, experience, and problem-solving skills of one or more human experts in a particular discipline. The Expert System is trained to analyze crop/plant status, to monitor the condition of the plants and the environment, and to adjust operational parameters to optimize the plant-growth process. This system is intended to provide a way to remotely control plant growth with little or no human intervention. More specifically, the term control implies an autonomous method for detecting plant states such as health (biomass) or stress and then for recommending and implementing cultivation and/or remediation to optimize plant growth and to minimize consumption of energy and nutrients. Because of difficulties associated with delivering energy and nutrients remotely, a key feature of this Expert System is its ability to minimize this effort and to achieve optimum growth while taking into account the diverse range of environmental considerations that exist in an enclosed environment. The plant-growth environment for the Expert System could be made from a variety of structures, including a greenhouse, an underground cavern, or another enclosed chamber. Imaging equipment positioned within or around the chamber provides spatially distributed crop/plant-growth information. Sensors mounted in the chamber provide data and information pertaining to environmental conditions that could affect plant development. Lamps in the growth environment structure supply illumination, and other additional equipment in the chamber supplies essential nutrients and chemicals.

  17. Plant growth-promoting bacteria for phytostabilization of mine tailings.

    Science.gov (United States)

    Grandlic, Christopher J; Mendez, Monica O; Chorover, Jon; Machado, Blenda; Maier, Raina M

    2008-03-15

    Eolian dispersion of mine tailings in arid and semiarid environments is an emerging global issue for which economical remediation alternatives are needed. Phytostabilization, the revegetation of these sites with native plants, is one such alternative. Revegetation often requires the addition of bulky amendments such as compost which greatly increases cost. We report the use of plant growth-promoting bacteria (PGPB) to enhance the revegetation of mine tailings and minimize the need for compost amendment. Twenty promising PGPB isolates were used as seed inoculants in a series of greenhouse studies to examine revegetation of an extremely acidic, high metal contenttailings sample previously shown to require 15% compost amendment for normal plant growth. Several isolates significantly enhanced growth of two native species, quailbush and buffalo grass, in tailings. In this study, PGPB/compost outcomes were plant specific; for quailbush, PGPB were most effective in combination with 10% compost addition while for buffalo grass, PGPB enhanced growth in the complete absence of compost. Results indicate that selected PGPB can improve plant establishment and reduce the need for compost amendment. Further, PGPB activities necessary for aiding plant growth in mine tailings likely include tolerance to acidic pH and metals.

  18. Paradigm shift in plant growth control.

    Science.gov (United States)

    Körner, Christian

    2015-06-01

    For plants to grow they need resources and appropriate conditions that these resources are converted into biomass. While acknowledging the importance of co-drivers, the classical view is still that carbon, that is, photosynthetic CO2 uptake, ranks above any other drivers of plant growth. Hence, theory and modelling of growth traditionally is carbon centric. Here, I suggest that this view is not reflecting reality, but emerged from the availability of methods and process understanding at leaf level. In most cases, poorly understood processes of tissue formation and cell growth are governing carbon demand, and thus, CO2 uptake. Carbon can only be converted into biomass to the extent chemical elements other than carbon, temperature or cell turgor permit. Copyright © 2015. Published by Elsevier Ltd.

  19. PLANT GROWTH-PROMOTING MICROBIAL INOCULANT FOR Schizolobium parahyba pv. parahyba

    Directory of Open Access Journals (Sweden)

    Priscila Jane Romano de Oliveira Gonçalves

    2015-08-01

    Full Text Available ABSTRACTSchizolobium parahyba pv. amazonicum (Huber ex Ducke Barneby (paricá occurs naturally in the Amazon and is significant commercial importance due to its rapid growth and excellent performance on cropping systems. The aim of this paper was to evaluate a microbial inoculants such as arbuscular mycorrhiza fungi (AMF and Rhizobium sp. that promote plant growth. The inocula was 10 g of root colonized and spores of Glomus clarum and/or 1 mL of cell suspension (107 CFU/mL of Rhizobium sp. and/or 100 g of chemical fertilizer NPK 20-05-20 per planting hole. The experimental design was complete randomized blocks with five replications and eight treatments (n = 800. Plant height, stem diameter and plant survival were measured. The results were tested for normality and homogeneity of variances and analyzed by ANOVA and Tukey test (p < 0.05. Rhizobium sp and AM fungi showed no effect on plant growth. Environmental factors probably influenced the effectiveness of symbiosis of both microorganisms and plant growth. The chemical fertilizer increased S. parahyba growth. During the first 120 days plants suffered with drought and frost, and at 180 days plants inoculated with microorganism plus chemical fertilizer showed higher survival when compared with control. The results showed that the microbial inoculants used showed an important role on plant survival after high stress conditions, but not in plant growth. Also was concluded that the planting time should be between November to December to avoid the presence of young plants during winter time that is dry and cold.

  20. Symbiotic regulation of plant growth, development and reproduction

    Science.gov (United States)

    Russell J. Rodriguez; D. Carl Freeman; E. Durant McArthur; Yong Ok Kim; Regina S. Redman

    2009-01-01

    The growth and development of rice (Oryzae sativa) seedlings was shown to be regulated epigenetically by a fungal endophyte. In contrast to un-inoculated (nonsymbiotic) plants, endophyte colonized (symbiotic) plants preferentially allocated resources into root growth until root hairs were well established. During that time symbiotic roots expanded at...

  1. Diversity and Plant Growth Promoting Proerties of Rhizobacteria ...

    African Journals Online (AJOL)

    The purpose of this study was to evaluate and assess the plant growth promoting characteristics and diversity of major tef rhizosphere isolates from central Ethiopia. A total of 162 bacteria were isolated from rhizosphere of tef [Eragrostis tef (Zucc.) Trotter] and characterized. While screening using some plant growth ...

  2. Differences in growth trajectory and strategy of two sympatric congeneric species in an Indonesian floodplain forest.

    Science.gov (United States)

    Yamada, Toshihiro; Ngakan, Oka Putu; Suzuki, Eizi

    2005-01-01

    Whole-plant development trajectories and sapling leaf displays were compared for two sympatric congeneric species, Pterospermum diversifolium and P. javanicum, in a tropical floodplain forest in East Kalimantan, Indonesia. We assessed their growth strategies and developed hypotheses for their coexistence within the community. Pterospermum diversifolium retains a monoaxial growth habit that promotes quick stem elongation; thus, it is taller when branches are initiated than is P. javanicum. The species differed significantly in height growth and total crown expansion per unit increment of biomass: monoaxial P. diversifolium saplings devote more effort to stem elongation, whereas branched P. javanicum saplings devote more effort to branch expansion. Monoaxial P. diversifolium sustained more severe self-shading than P. javanicum. The sapling growth strategy of P. diversifolium appears to be dynamic, emphasizing the opportunistic use of light following a disturbance, whereas that of P. javanicum appears to be static, optimizing leaf display for current light conditions. The advantages of these strategies depend on context, and the two species may coexist within a community by adopting different regeneration niches based on differing understory light conditions: P. diversifolium is favored over P. javanicum at high light levels, but the opposite is true at low light levels.

  3. Simulated geographic variations of plant species richness, evenness and abundance using climatic constraints on plant functional diversity

    International Nuclear Information System (INIS)

    Kleidon, Axel; Pavlick, Ryan; Reu, Bjoern; Adams, Jonathan

    2009-01-01

    Among the most pronounced large-scale geographic patterns of plant biodiversity are the increase in plant species richness towards the tropics, a more even distribution of the relative abundances of plant species in the tropics, and a nearly log-normal relative abundance distribution. Here we use an individual-based plant diversity model that relates climatic constraints to feasible plant growth strategies to show that all three basic diversity patterns can be predicted merely from the climatic constraints acting upon plant ecophysiological trade-offs. Our model predicts that towards objectively 'harsher' environments, the range of feasible growth strategies resulting in reproductive plants is reduced, thus resulting in lower functional plant species richness. The reduction of evenness is attributed to a more rapid decline in productivity from the most productive to less productive plant growth strategies since the particular setup of the strategy becomes more important in maintaining high productivity in harsher environments. This approach is also able to reproduce the increase in the deviation from a log-normal distribution towards more evenly distributed communities of the tropics. Our results imply that these general biodiversity relationships can be understood primarily by considering the climatic constraints on plant ecophysiological trade-offs.

  4. Strategies for growth of thermal power

    International Nuclear Information System (INIS)

    Shah, R.K.D.

    1998-01-01

    The power generating industry in India is at the cross roads. Massive investments are required to achieve GDP growth of 7-8% per annum over the next 10 years. For this, appropriate strategies have to be evolved which will give the country best returns. With coal being the major fuel resource in India, thermal power generation will continue to be the mainstay in the next decade. This paper covers various key issues to be addressed covering the plan and perspectives of thermal power, environmental issues, technology strategies for growth, power policy and R and D. (author)

  5. Design and construction of an inexpensive homemade plant growth chamber.

    Science.gov (United States)

    Katagiri, Fumiaki; Canelon-Suarez, Dario; Griffin, Kelsey; Petersen, John; Meyer, Rachel K; Siegle, Megan; Mase, Keisuke

    2015-01-01

    Plant growth chambers produce controlled environments, which are crucial in making reproducible observations in experimental plant biology research. Commercial plant growth chambers can provide precise controls of environmental parameters, such as temperature, humidity, and light cycle, and the capability via complex programming to regulate these environmental parameters. But they are expensive. The high cost of maintaining a controlled growth environment is often a limiting factor when determining experiment size and feasibility. To overcome the limitation of commercial growth chambers, we designed and constructed an inexpensive plant growth chamber with consumer products for a material cost of $2,300. For a comparable growth space, a commercial plant growth chamber could cost $40,000 or more. Our plant growth chamber had outside dimensions of 1.5 m (W) x 1.8 m (D) x 2 m (H), providing a total growth area of 4.5 m2 with 40-cm high clearance. The dimensions of the growth area and height can be flexibly changed. Fluorescent lights with large reflectors provided a relatively spatially uniform photosynthetically active radiation intensity of 140-250 μmoles/m2/sec. A portable air conditioner provided an ample cooling capacity, and a cooling water mister acted as a powerful humidifier. Temperature, relative humidity, and light cycle inside the chamber were controlled via a z-wave home automation system, which allowed the environmental parameters to be monitored and programmed through the internet. In our setting, the temperature was tightly controlled: 22.2°C±0.8°C. The one-hour average relative humidity was maintained at 75%±7% with short spikes up to ±15%. Using the interaction between Arabidopsis and one of its bacterial pathogens as a test experimental system, we demonstrate that experimental results produced in our chamber were highly comparable to those obtained in a commercial growth chamber. In summary, our design of an inexpensive plant growth chamber

  6. Design and construction of an inexpensive homemade plant growth chamber.

    Directory of Open Access Journals (Sweden)

    Fumiaki Katagiri

    Full Text Available Plant growth chambers produce controlled environments, which are crucial in making reproducible observations in experimental plant biology research. Commercial plant growth chambers can provide precise controls of environmental parameters, such as temperature, humidity, and light cycle, and the capability via complex programming to regulate these environmental parameters. But they are expensive. The high cost of maintaining a controlled growth environment is often a limiting factor when determining experiment size and feasibility. To overcome the limitation of commercial growth chambers, we designed and constructed an inexpensive plant growth chamber with consumer products for a material cost of $2,300. For a comparable growth space, a commercial plant growth chamber could cost $40,000 or more. Our plant growth chamber had outside dimensions of 1.5 m (W x 1.8 m (D x 2 m (H, providing a total growth area of 4.5 m2 with 40-cm high clearance. The dimensions of the growth area and height can be flexibly changed. Fluorescent lights with large reflectors provided a relatively spatially uniform photosynthetically active radiation intensity of 140-250 μmoles/m2/sec. A portable air conditioner provided an ample cooling capacity, and a cooling water mister acted as a powerful humidifier. Temperature, relative humidity, and light cycle inside the chamber were controlled via a z-wave home automation system, which allowed the environmental parameters to be monitored and programmed through the internet. In our setting, the temperature was tightly controlled: 22.2°C±0.8°C. The one-hour average relative humidity was maintained at 75%±7% with short spikes up to ±15%. Using the interaction between Arabidopsis and one of its bacterial pathogens as a test experimental system, we demonstrate that experimental results produced in our chamber were highly comparable to those obtained in a commercial growth chamber. In summary, our design of an inexpensive plant

  7. Plant Water Use Strategy in Response to Spatial and Temporal Variation in Precipitation Patterns in China: A Stable Isotope Analysis

    Directory of Open Access Journals (Sweden)

    Ying Zhao

    2018-03-01

    Full Text Available Spatial and temporal variation in precipitation patterns can directly alter the survival and growth of plants, yet in China there is no comprehensive and systematic strategy for plant use based on the effects of precipitation patterns. Here, we examined information from 93 published papers (368 plant species on plant xylem water stable isotopes (δD and δ18O in China. The results showed that: (1 The slope of the local meteoric water line (LMWL gradually increased from inland areas to the coast, as a result of continental and seasonal effects. The correlation between δD and δ18O in plant stem water is also well fitted and the correlation coefficients range from 0.78 to 0.89. With respect to the soil water line, the δ18O values in relation to depth (0–100 cm varied over time; (2 Plants’ main water sources are largely affected by precipitation patterns. In general, plants prioritize the use of stable and continuous water sources, while they have a more variable water uptake strategy under drought conditions; (3 There are no spatial and temporal variations in the contribution of the main water source (p > 0.05 because plants maintain growth by shifting their use of water sources when resources are unreliable.

  8. Rhizosphere of rice plants harbor bacteria with multiple plant growth ...

    African Journals Online (AJOL)

    Rhizosphere of rice plants harbor bacteria with multiple plant growth promoting features. ... 45 (39.46%) isolates were capable of producing siderophore, the range of production being 4.50 to 223.26 μg mg-1 protein. Analysis of molecular diversity was made by amplified ribosomal DNA restriction analysis (ARDRA) and ...

  9. Crop growth, light utilization and yield of relay intercropped cotton as affected by plant density and a plant growth regulator

    NARCIS (Netherlands)

    Mao, L.; Zhang, L.; Zhao, X.; Liu, S.; Werf, van der W.; Zhang, S.; Spiertz, J.H.J.; Li, Z.

    2014-01-01

    Modern cotton cultivation requires high plant densities and compact plants. Here we study planting density and growth regulator effects on plant structure and production of cotton when the cotton is grown in a relay intercrop with wheat, a cultivation system that is widespread in China. Field

  10. How Will Global Environmental Changes Affect the Growth of Alien Plants?

    Directory of Open Access Journals (Sweden)

    Jujie Jia

    2016-11-01

    Full Text Available Global environmental changes can create novel habitats, promoting the growth of alien plants that often exhibit broad environmental tolerance and high phenotypic plasticity. However, the mechanisms underlying these growth promotory effects are unknown at present. Here, we conducted a phylogenetically controlled meta-analysis using data from 111 published studies encompassing the responses of 129 alien plants to global warming, increased precipitation, N deposition, and CO2 enrichment. We compared the differences in the responses of alien plants to the four global environmental change factors across six categories of functional traits between woody and non-woody life forms as well as C3 and C4 photosynthetic pathways. Our results showed that all four global change factors promote alien plant growth. Warming had a more positive effect on C4 than C3 plants. Although the effects of the four factors on the functional traits of alien plants were variable, plant growth was mainly promoted via an increase in growth rate and size. Our data suggest that potential future global environmental changes could further facilitate alien plant growth.

  11. 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 ...

  12. Seedling Growth Strategies in Bauhinia Species: Comparing Lianas and Trees

    Science.gov (United States)

    Cai, Zhi-Quan; Poorter, Lourens; Cao, Kun-Fang; Bongers, Frans

    2007-01-01

    Background and Aims Lianas are expected to differ from trees in their growth strategies. As a result these two groups of woody species will have different spatial distributions: lianas are more common in high light environments. This study determines the differences in growth patterns, biomass allocation and leaf traits in five closely related liana and tree species of the genus Bauhinia. Methods Seedlings of two light-demanding lianas (Bauhinia tenuiflora and B. claviflora), one shade-tolerant liana (B. aurea), and two light-demanding trees (B. purpurea and B. monandra) were grown in a shadehouse at 25 % of full sunlight. A range of physiological, morphological and biomass parameters at the leaf and whole plant level were compared among these five species. Key Results The two light-demanding liana species had higher relative growth rate (RGR), allocated more biomass to leaf production [higher leaf mass fraction (LMF) and higher leaf area ratio (LAR)] and stem mass fraction (SMF), and less biomass to the roots [root mass fraction (RMF)] than the two tree species. The shade-tolerant liana had the lowest RGR of all five species, and had a higher RMF, lower SMF and similar LMF than the two light-demanding liana species. The two light-demanding lianas had lower photosynthetic rates per unit area (Aarea) and similar photosynthetic rates per unit mass (Amass) than the trees. Across species, RGR was positively related to SLA, but not to LAR and Aarea. Conclusions It is concluded that the faster growth of light-demanding lianas compared with light-demanding trees is based on morphological parameters (SLA, LMF and LAR), and cannot be attributed to higher photosynthetic rates at the leaf level. The shade-tolerant liana exhibited a slow-growth strategy, compared with the light-demanding species. PMID:17720978

  13. Isolation, Characterization, Screening, Formulation and Evaluation of Plant Growth Promoting Rhizobacteria

    Directory of Open Access Journals (Sweden)

    Puja Kumari

    2017-10-01

    Full Text Available Plant growth promoting rhizobacteria (PGPR are bioresources which may be viewed as a novel and potential tool for providing substantial benefits to the agriculture. Soil is the dynamic living matrix and the major source of food security providing various resources of plant growth and maintaining life processes. PGPR are originally defined as root- colonizing bacteria that cause either plant growth promotion or biological control of plant diseases. Chemical fertilizers are used for killing pathogens, increase crop yield but long term use of chemical fertilizers lead to adverse effect to the soil profile and is the reason for decrease in soil productivity, on the other hand PGPR promote plant growth directly by either facilitating resource acquisition (nitrogen, phosphorus and essential minerals or modulating plant hormone levels, or indirectly by decreasing the inhibitory effects of various pathogens on plant growth and development in the forms of biocontrol agents. PGPR is the indispensable part of rhizosphere biota that when grown in association with the host plants can stimulate the growth of the host. PGPR seemed as successful rhizobacteria in getting established in soil ecosystem due to their high adaptability in a wide variety of environments, faster growth rate and biochemical versatility to metabolize a wide range of natural and xenobiotic compounds. Isolated PGPRs from selective crop rizosphere soil were used for further growth promotion and biocontrol studies in the green house and field. Different studies have been carrying out to develop some new bioformulations and evaluate their efficacy in promoting crop seedlings growth characteristics. Field trials were performed to evaluate selective crops with formulations of several plants PGPR in a production system. The present review highlights the Plant growth promoting rhizobacteria as an alternative of chemical fertilizer for sustainable, environment friendly agriculture.

  14. Isolation of plant growth promoting rhizobacteria of guava plants (Psidium guajava

    Directory of Open Access Journals (Sweden)

    Blanca Estela Gómez Luna

    2012-09-01

    Full Text Available Guava production for 2008 in the state of Guanajuato was 177 ha in area planted and the same number of area harvested, production in 1,130.80 Ton. In traditional farming practices have made excessive use of mineral fertilizers, which, if it is true, ensure a good production are expensive and come to cause imbalances in agroecosystems by contamination of soil, water, and food. In this work we evaluated the effect of Bacillus subtilis strains as plant growth promoter rhizobacteria in guava plants under greenhouse conditions. We used three strains were inoculated potted plant with guava. We measured the height, number of branches and leaves. Guava orchards of 2 then display of soil were taken for the isolation andcharacterization of rhizobacteria. Selective medium was used with 1 - carboxylic acid, -1 - aminocyclopropane and selecting bacteria with ACC desaminase activity. For the isolates were determined antibiotic resistance, confrontation with fungal pathogens, plant growth tests in vitro and BIOLOG metabolic profiles. We found 30 isolates with ACC activities, 7 have the effect of biological control and 5 had effect on root development in vitro. The use of growth promotingrhizobacteria are an excellent alternative for improving the production of guavas, growing very little is known of themicroflora associated with the rhizosphere and the ecological role they have in the ground.

  15. Phytomanagement of Cd-contaminated soils using maize (Zea mays L.) assisted by plant growth-promoting rhizobacteria.

    Science.gov (United States)

    Moreira, Helena; Marques, Ana P G C; Franco, Albina R; Rangel, António O S S; Castro, Paula M L

    2014-01-01

    Zea mays (L.) is a crop widely cultivated throughout the world and can be considered suitable for phytomanagement due to its metal resistance and energetic value. In this study, the effect of two plant growth-promoting rhizobacteria, Ralstonia eutropha and Chryseobacterium humi, on growth and metal uptake of Z. mays plants in soils contaminated with up to 30 mg Cd kg(-1) was evaluated. Bacterial inoculation increased plant biomass up to 63% and led to a decrease of up to 81% in Cd shoot levels (4-88 mg Cd kg(-1)) and to an increase of up to 186% in accumulation in the roots (52-134 mg Cd kg(-1)). The rhizosphere community structure changed throughout the experiment and varied with different levels of Cd soil contamination, as revealed by molecular biology techniques. Z. mays plants inoculated with either of the tested strains may have potential application in a strategy of soil remediation, in particular short-term phytostabilization, coupled with biomass production for energy purposes.

  16. Using Remote Sensing Mapping and Growth Response to Environmental Variability to Aide Aquatic Invasive Plant Management

    Science.gov (United States)

    Bubenheim, David L.; Schlick, Greg; Genovese, Vanessa; Wilson, Kenneth D.

    2018-01-01

    Management of aquatic weeds in complex watersheds and river systems present many challenges to assessment, planning and implementation of management practices for floating and submerged aquatic invasive plants. The Delta Region Areawide Aquatic Weed Project (DRAAWP), a USDA sponsored area-wide project, is working to enhance planning, decision-making and operational efficiency in the California Sacramento-San Joaquin Delta. Satellite and airborne remote sensing are used map (area coverage and biomass density), direct operations, and assess management impacts on plant communities. Archived satellite records enable review of results following previous climate and management events and aide in developing long-term strategies. Examples of remote sensing aiding effectiveness of aquatic weed management will be discussed as well as areas for potential technological improvement. Modeling at local and watershed scales using the SWAT modeling tool provides insight into land-use effects on water quality (described by Zhang in same Symposium). Controlled environment growth studies have been conducted to quantify the growth response of invasive aquatic plants to water quality and other environmental factors. Environmental variability occurs across a range of time scales from long-term climate and seasonal trends to short-term water flow mediated variations. Response time for invasive species response are examined at time scales of weeks, day, and hours using a combination of study duration and growth assessment techniques to assess water quality, temperature (air and water), nitrogen, phosphorus, and light effects. These provide response parameters for plant growth models in response to the variation and interact with management and economic models associated with aquatic weed management. Plant growth models are to be informed by remote sensing and applied spatially across the Delta to balance location and type of aquatic plant, growth response to altered environments and

  17. Plant growth and resistance promoted by Streptomyces spp. in tomato.

    Science.gov (United States)

    Dias, Maila P; Bastos, Matheus S; Xavier, Vanessa B; Cassel, Eduardo; Astarita, Leandro V; Santarém, Eliane R

    2017-09-01

    Plant Growth Promoting Rhizobacteria (PGPR) represent an alternative to improve plant growth and yield as well as to act as agents of biocontrol. This study characterized isolates of Streptomyces spp. (Stm) as PGPR, determined the antagonism of these isolates against Pectobacterium carotovorum subsp. brasiliensis (Pcb), evaluated the ability of Stm on promoting growth and modulating the defense-related metabolism of tomato plants, and the potential of Stm isolates on reducing soft rot disease in this species. The VOC profile of Stm was also verified. Promotion of plant growth was assessed indirectly through VOC emission and by direct interaction with Stm isolates in the roots. Evaluation of soft rot disease was performed in vitro on plants treated with Stm and challenged with Pcb. Enzymes related to plant defense were then analyzed in plants treated with three selected isolates of Stm, and PM1 was chosen for further Pcb-challenging experiment. Streptomyces spp. isolates displayed characteristics of PGPR. PM3 was the isolate with efficient antagonism against Pcb by dual-culture. Most of the isolates promoted growth of root and shoot of tomato plants by VOC, and PM5 was the isolate that most promoted growth by direct interaction with Stm. Soft rot disease and mortality of plants were significantly reduced when plants were treated with StmPM1. Modulation of secondary metabolism was observed with Stm treatment, and fast response of polyphenoloxidases was detected in plants pretreated with StmPM1 and challenged with Pcb. Peroxidase was significantly activated three days after infection with Pcb in plants pretreated with StmPM1. Results suggest that Streptomyces sp. PM1 and PM5 have the potential to act as PGPR. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  18. 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.

  19. Does investment in leaf defenses drive changes in leaf economic strategy? A focus on whole-plant ontogeny.

    Science.gov (United States)

    Mason, Chase M; Donovan, Lisa A

    2015-04-01

    Leaf defenses have long been studied in the context of plant growth rate, resource availability, and optimal investment theory. Likewise, one of the central modern paradigms of plant ecophysiology, the leaf economics spectrum (LES), has been extensively studied in the context of these factors across ecological scales ranging from global species data sets to temporal shifts within individuals. Despite strong physiological links between LES strategy and leaf defenses in structure, function, and resource investment, the relationship between these trait classes has not been well explored. This study investigates the relationship between leaf defenses and LES strategy across whole-plant ontogeny in three diverse Helianthus species known to exhibit dramatic ontogenetic shifts in LES strategy, focusing primarily on physical and quantitative chemical defenses. Plants were grown under controlled environmental conditions and sampled for LES and defense traits at four ontogenetic stages. Defenses were found to shift strongly with ontogeny, and to correlate strongly with LES strategy. More advanced ontogenetic stages with more conservative LES strategy leaves had higher tannin activity and toughness in all species, and higher leaf dry matter content in two of three species. Modeling results in two species support the conclusion that changes in defenses drive changes in LES strategy through ontogeny, and in one species that changes in defenses and LES strategy are likely independently driven by ontogeny. Results of this study support the hypothesis that leaf-level allocation to defenses might be an important determinant of leaf economic traits, where high investment in defenses drives a conservative LES strategy.

  20. Differential growth responses of Brachypodium distachyon genotypes to inoculation with plant growth promoting rhizobacteria.

    Science.gov (United States)

    do Amaral, Fernanda P; Pankievicz, Vânia C S; Arisi, Ana Carolina M; de Souza, Emanuel M; Pedrosa, Fabio; Stacey, Gary

    2016-04-01

    Plant growth promoting rhizobacteria (PGPR) can associate and enhance the growth of important crop grasses. However, in most cases, the molecular mechanisms responsible for growth promotion are not known. Such research could benefit by the adoption of a grass model species that showed a positive response to bacterial inoculation and was amenable to genetic and molecular research methods. In this work we inoculated different genotypes of the model grass Brachypodium distachyon with two, well-characterized PGPR bacteria, Azospirillum brasilense and Herbaspirillum seropedicae, and evaluated the growth response. Plants were grown in soil under no nitrogen or with low nitrogen (i.e., 0.5 mM KNO3). A variety of growth parameters (e.g., shoot height, root length, number of lateral roots, fresh and dry weight) were measured 35 days after inoculation. The data indicate that plant genotype plays a very important role in determining the plant response to PGPR inoculation. A positive growth response was observed with only four genotypes grown under no nitrogen and three genotypes tested under low nitrogen. However, in contrast, relatively good root colonization was seen with most genotypes, as measured by drop plate counting and direct, microscopic examination of roots. In particular, the endophytic bacteria H. seropedicae showed strong epiphytic and endophytic colonization of roots.

  1. Isolation and selection of plant growth-promoting bacteria associated with sugarcane

    Directory of Open Access Journals (Sweden)

    Ariana Alves Rodrigues

    2016-06-01

    Full Text Available Microorganisms play a vital role in maintaining soil fertility and plant health. They can act as biofertilizers and increase the resistance to biotic and abiotic stress. This study aimed at isolating and characterizing plant growth-promoting bacteria associated with sugarcane, as well as assessing their ability to promote plant growth. Endophytic bacteria from leaf, stem, root and rhizosphere were isolated from the RB 867515 commercial sugarcane variety and screened for indole acetic acid (IAA production, ability to solubilize phosphate, fix nitrogen and produce hydrogen cyanide (HCN, ammonia and the enzymes pectinase, cellulase and chitinase. A total of 136 bacteria were isolated, with 83 of them presenting some plant growth mechanism: 47 % phosphate solubilizers, 26 % nitrogen fixers and 57 % producing IAA, 0.7 % HCN and chitinase, 45 % ammonia, 30 % cellulose and 8 % pectinase. The seven best isolates were tested for their ability to promote plant growth in maize. The isolates tested for plant growth promotion belong to the Enterobacteriaceae family and the Klebsiella, Enterobacter and Pantoea genera. Five isolates promoted plant growth in greenhouse experiments, showing potential as biofertilizers.

  2. The influence of growth retardants and cytokinins on flowering of ornamental plants

    Directory of Open Access Journals (Sweden)

    Anna Pobudkiewicz

    2012-12-01

    Full Text Available Growth retardants are applied in order to obtain short and well compact plants. They usually inhibit stem elongation, but also can influence the flowering of plants. The aim of cytokinin application is to obtain well branched plants without removing the apical meristem. Cytokinins usually increase the number of axillary shoots but also can influence flowering. Growth retardants and cytokinins can affect flower size, pedicel length, number of flowers, flower longevity, abortion of flower buds and number of days from potting plants to the first open flower. Flowering of growth retardant and cytokinin treated plants might depend on the method of growth regulator used (foliar spray or soil drench, plant species or even a plant cultivar, but in the highest degree it depends on the growth regulator rate used. These growth regulators, when are applied at rates appropriate for height and habit control, very seldom influence flowering of ornamental plants, but applied at high rates can delay flowering, diminish flower diameter or flower pedicel length and also can decrease the number of flowers per plant. In cultivation of bulb plants, growth retardants, used at very high rates, also cause abortion of flower buds.

  3. 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.

  4. Surveying some strategies of cultural management on species growth indices and yield in the field of soybean

    Directory of Open Access Journals (Sweden)

    habibeh soltani

    2018-01-01

    Full Text Available Introduction soybean (Glycine max L. plays an important role in three major markets of grains, oil and meal. damage of weeds in soybean generally 13 to 60 and sometimes more than %80 have been reported Farming methods through proper management, sowing date and by use of optimum density could be a strategy for the development of ecological competitiveness of crops and inhibit weed growth are the comparison the growth indices to design interference models of weed and crop and estimate crop yield loss in competition with weed is essential and allow to plant breeding researcher to choice the more competitive varieties of crop in competition with weed. Materials and Methods With the aim of influencing sowing date and plant density on the growth indices and evaluation the competitive ability of soybean cultivar Williams with weeds, an experiment was conducted in 2013, at Agricultural Research Station, Ferdowsi University of Mashhad, as split-split based on a randomized complete block design with three replications. Main plot included three sowing dates levels (17 April, 12 May, 6 June and sub - plots included four crop density (30, 40, 50 and 60 plant . m-2 and sub - sub plots included weed management of two level (weed infested and weedy control. First sampling was started at 35 days after planting and was every 14 days until the end of growth period. Leaf area index, dry matter, crop growth rate and the growth rate were calculated Results and Discussion The results showed that 11 species weed belonging to 9 families observed and identified. In the early stages of growth, leaf area index and dry matter increased slowly, but in the seven to eight leaf stage of plant growth (Log phase, leaf area index and dry matter increased rapidly, and a little upon entry to the plant Physiological maturity period (Early seedling peeks, and again began to decline at the end of seedling. The sowing date 12 May in contrast to early sowing date (17 April and delayed

  5. Productivity growth patterns in US dairy products manufacturing plants

    NARCIS (Netherlands)

    Geylani, P.C.; Stefanou, S.E.

    2011-01-01

    We analyse the productivity growth patterns in the US dairy products industry using the Census Bureau's plant-level data set. We decompose Total Factor Productivity (TFP) growth into the scale and technical change components and analyse variability of plants' productivity by constructing transition

  6. Plant Growth Absorption Spectrum Mimicking Light Sources

    Directory of Open Access Journals (Sweden)

    Jwo-Huei Jou

    2015-08-01

    Full Text Available Plant factories have attracted increasing attention because they can produce fresh fruits and vegetables free from pesticides in all weather. However, the emission spectra from current light sources significantly mismatch the spectra absorbed by plants. We demonstrate a concept of using multiple broad-band as well as narrow-band solid-state lighting technologies to design plant-growth light sources. Take an organic light-emitting diode (OLED, for example; the resulting light source shows an 84% resemblance with the photosynthetic action spectrum as a twin-peak blue dye and a diffused mono-peak red dye are employed. This OLED can also show a greater than 90% resemblance as an additional deeper red emitter is added. For a typical LED, the resemblance can be improved to 91% if two additional blue and red LEDs are incorporated. The approach may facilitate either an ideal use of the energy applied for plant growth and/or the design of better light sources for growing different plants.

  7. Government Expenditure on Growth Strategies and Poverty ...

    African Journals Online (AJOL)

    poverty and government expenditure on growth strategies that have been implemented in Tanzania since the mid 2000s. The paper shows that despite impressive economic growth of about 6 percent per annum that the country has enjoyed in ...

  8. Fusarium oxysporum volatiles enhance plant growth via affecting auxin transport and signaling

    Directory of Open Access Journals (Sweden)

    Vasileios eBitas

    2015-11-01

    Full Text Available Volatile organic compounds (VOCs have well-documented roles in plant-plant communication and directing animal behavior. In this study, we examine the less understood roles of VOCs in plant-fungal relationships. Phylogenetically and ecologically diverse strains of Fusarium oxysporum, a fungal species complex that often resides in the rhizosphere of assorted plants, produce volatile compounds that augment shoot and root growth of Arabidopsis thaliana and tobacco. Growth responses of A. thaliana hormone signaling mutants and expression patterns of a GUS reporter gene under the auxin-responsive DR5 promoter supported the involvement of auxin signaling in F. oxysporum volatile-mediated growth enhancement. In addition, 1-naphthylthalamic acid, an inhibitor of auxin efflux, negated F. oxysporum volatile-mediated growth enhancement in both plants. Comparison of the profiles of volatile compounds produced by F. oxysporum strains that differentially affected plant growth suggests that the relative compositions of both growth inhibitory and stimulatory compounds may determine the degree of plant growth enhancement. Volatile-mediated signaling between fungi and plants may represent a potentially conserved, yet mostly overlooked, mechanism underpinning plant-fungus interactions and fungal niche adaption.

  9. Auxin-BR Interaction Regulates Plant Growth and Development

    Science.gov (United States)

    Tian, Huiyu; Lv, Bingsheng; Ding, Tingting; Bai, Mingyi; Ding, Zhaojun

    2018-01-01

    Plants develop a high flexibility to alter growth, development, and metabolism to adapt to the ever-changing environments. Multiple signaling pathways are involved in these processes and the molecular pathways to transduce various developmental signals are not linear but are interconnected by a complex network and even feedback mutually to achieve the final outcome. This review will focus on two important plant hormones, auxin and brassinosteroid (BR), based on the most recent progresses about these two hormone regulated plant growth and development in Arabidopsis, and highlight the cross-talks between these two phytohormones. PMID:29403511

  10. Effects of microgravity on growth hormone concentration and distribution in plants

    Science.gov (United States)

    Schulze, Aga; Jensen, Philip; Desrosiers, Mark; Bandurski, Robert S.

    1989-01-01

    On earth, gravity affects the distribution of the plant growth hormone, indole-3-acetic acid (IAA), in a manner such that the plant grows into a normal vertical orientation (shoots up, roots down). How the plant controls the amount and distribution of IAA is only partially understood and is currently under investigation in this laboratory. The question to be answered in the flight experiment concerns the effect of gravity on the concentration, turn over, and distribution of the growth hormone. The answer to this question will aid in understanding the mechanism by which plants control the amount and distribution of growth hormone. Such knowledge of a plant's hormonal metabolism may aid in the growth of plants in space and will lead to agronomic advances.

  11. Nuclear Power Plant Outage Optimization Strategy. 2016 Edition

    International Nuclear Information System (INIS)

    2016-10-01

    This publication is an update of IAEA-TECDOC-1315, Nuclear Power Plant Outage Optimisation Strategy, which was published in 2002, and aims to communicate good outage management practices in a manner that can be used by operators and utilities in Member States. Nuclear power plant outage management is a key factor for safe and economic nuclear power plant performance. This publication discusses plant outage strategy and how this strategy is actually implemented. The main areas that are important for outage optimization that were identified by the utilities and government organizations participating in this report are: 1) organization and management; 2) outage planning and preparation; 3) outage execution; 4) safety outage review; and 5) counter measures to avoid the extension of outages and to facilitate the work in forced outages. Good outage management practices cover many different areas of work and this publication aims to communicate these good practices in a way that they can be used effectively by operators and utilities

  12. Ethylene production throughout growth and development of plants

    Science.gov (United States)

    Wheeler, Raymond M.; Peterson, Barbara V.; Stutte, Gary W.

    2004-01-01

    Ethylene production by 10 or 20 m2 stands of wheat, soybean, lettuce, potato, and tomato was monitored throughout growth and development in an atmospherically closed plant chamber. Chamber ethylene levels varied among species and rose during periods of canopy expansion and rapid growth for all species. Following this, ethylene levels either declined during seed fill and maturation for wheat and soybean, or remained relatively constant for potato and tomato (during flowering and early fruit development). Lettuce plants were harvested during rapid growth and peak ethylene production. Chamber ethylene levels increased rapidly during tomato ripening, reaching concentrations about 10 times that measured during vegetative growth. The highest ethylene production rates during vegetative growth ranged from 1.6 to 2.5 nmol m-2 d-1 during rapid growth of lettuce and wheat stands, or about 0.3 to 0.5 nmol g-1 fresh weight per hour. Estimates of stand ethylene production during tomato ripening showed that rates reached 43 nmol m-2 d-1 in one study and 93 nmol m-2 d-1 in a second study with higher lighting, or about 50x that of the rate during vegetative growth of tomato. In a related test with potato, the photoperiod was extended from 12 to 24 hours (continuous light) at 58 days after planting (to increase tuber yield), but this change in the environment caused a sharp increase in ethylene production from the basal rate of 0.4 to 6.2 nmol m-2 d-1. Following this, the photoperiod was changed back to 12 h at 61 days and ethylene levels decreased. The results suggest three separate categories of ethylene production were observed with whole stands of plants: 1) production during rapid vegetative growth, 2) production during climacteric fruit ripening, and 3) production from environmental stress.

  13. Study on growth-promotion of paddy plants treated with oligo chitosan

    International Nuclear Information System (INIS)

    Norhashidah Talip; Maznah Mahmud; Norzita Yacob; Kamaruddin Hashim; Khairul Zaman Mohd Dahlan

    2010-01-01

    Chitosan has been degraded to produced oligo chitosan with different molecular weight using gamma ray irradiation from a Co-60 source in solid state (powder form) and liquid state (aqueous solution). Study on growth promotion of paddy plants was done using oligo chitosan and conventional plant growth promoter as a comparison. Oligo chitosan was used with different molecular weight and different concentrations. Smaller molecular weight of oligo chitosan with smaller concentration showed better result than bigger molecular weight of oligo chitosan as a plant growth promoter. This study also showed that conventional growth promoter can be replaced with oligo chitosan as it is more effective as plant growth promoter as well as more environmental friendly. (author)

  14. Impact of Wood Biochar and Its Interactions with Mycorrhizal Fungi, Phosphorus Fertilization and Irrigation Strategies on Potato Growth

    DEFF Research Database (Denmark)

    Liu, C.; Liu, F.; Ravnskov, S.

    2017-01-01

    Biochar amendment to soil has the potential to improve soil quality and increase crop yield. Arbuscular mycorrhizal fungi (AMF) provide beneficial plant services of stress alleviation with respect to phosphorus (P) deficiency and drought. The aim of this study was to explore interactive effects...... of biochar with AMF, P fertilization levels and irrigation strategies on growth of potato plants. Potato plants were amended with wood biochar of 0.74 % w/w (B+) or not (B−), fertilized with phosphorus of 0.11 mg P g−1 soil (P1) or not (P0), irrigated with full irrigation (FI) or partial root-zone drying...... irrigation (PRD) and inoculated with AMF of Rhizophagus irregularis (M+) or not (M−) in split-root pots in a sandy loam soil. Plants were analysed for growth performance, P and nitrogen (N) uptake and water use efficiency (WUE). Biochar adsorption of mineral P and N in aqueous solution was tested...

  15. Phytohormone profiles induced by trichoderma isolates correspond with their biocontrol and plant growth-promoting activity on melon plants.

    Science.gov (United States)

    Martínez-Medina, Ainhoa; Del Mar Alguacil, Maria; Pascual, Jose A; Van Wees, Saskia C M

    2014-07-01

    The application of Trichoderma strains with biocontrol and plant growth-promoting capacities to plant substrates can help reduce the input of chemical pesticides and fertilizers in agriculture. Some Trichoderma isolates can directly affect plant pathogens, but they also are known to influence the phytohormonal network of their host plant, thus leading to an improvement of plant growth and stress tolerance. In this study, we tested whether alterations in the phytohormone signature induced by different Trichoderma isolates correspond with their ability for biocontrol and growth promotion. Four Trichoderma isolates were collected from agricultural soils and were identified as the species Trichoderma harzianum (two isolates), Trichoderma ghanense, and Trichoderma hamatum. Their antagonistic activity against the plant pathogen Fusarium oxysporum f. sp. melonis was tested in vitro, and their plant growth-promoting and biocontrol activity against Fusarium wilt on melon plants was examined in vivo, and compared to that of the commercial strain T. harzianum T-22. Several growth- and defense-related phytohormones were analyzed in the shoots of plants that were root-colonized by the different Trichoderma isolates. An increase in auxin and a decrease in cytokinins and abscisic acid content were induced by the isolates that promoted the plant growth. Principal component analysis (PCA) was used to evaluate the relationship between the plant phenotypic and hormonal variables. PCA pointed to a strong association of auxin induction with plant growth stimulation by Trichoderma. Furthermore, the disease-protectant ability of the Trichoderma strains against F. oxysporum infection seems to be more related to their induced alterations in the content of the hormones abscisic acid, ethylene, and the cytokinin trans-zeatin riboside than to the in vitro antagonism activity against F. oxysporum.

  16. Transgenic Strategies for Enhancement of Nematode Resistance in Plants

    Directory of Open Access Journals (Sweden)

    Muhammad A. Ali

    2017-05-01

    Full Text Available Plant parasitic nematodes (PPNs are obligate biotrophic parasites causing serious damage and reduction in crop yields. Several economically important genera parasitize various crop plants. The root-knot, root lesion, and cyst nematodes are the three most economically damaging genera of PPNs on crops within the family Heteroderidae. It is very important to devise various management strategies against PPNs in economically important crop plants. Genetic engineering has proven a promising tool for the development of biotic and abiotic stress tolerance in crop plants. Additionally, the genetic engineering leading to transgenic plants harboring nematode resistance genes has demonstrated its significance in the field of plant nematology. Here, we have discussed the use of genetic engineering for the development of nematode resistance in plants. This review article also provides a detailed account of transgenic strategies for the resistance against PPNs. The strategies include natural resistance genes, cloning of proteinase inhibitor coding genes, anti-nematodal proteins and use of RNA interference to suppress nematode effectors. Furthermore, the manipulation of expression levels of genes induced and suppressed by nematodes has also been suggested as an innovative approach for inducing nematode resistance in plants. The information in this article will provide an array of possibilities to engineer resistance against PPNs in different crop plants.

  17. Effect of Plant Growth Regulator on Red Onion Cultivation from True Seed Shallot (TSS

    Directory of Open Access Journals (Sweden)

    Tri Sudaryono

    2018-01-01

    Full Text Available Red onion is one of the strategic horticultural commodities, considering this commodity is very high consumption as a daily spice and fluctuating price. Therefore is not surprising that these commodities are contributing to inflation. Efforts to meet increasing consumption needs, it is necessary to find the right strategy to increase domestic red onion production. One of the strategies considered to increase domestic red onion production is the use of botanical seed (TSS as a source of seed on shallot cultivation. There are 2 main weaknesses of red onion cultivation with TSS as a source of seeds. The two weaknesses are TSS low growing power, which is naturally only in the 50-60 % range and the number of tubers produced is less than 3 cloves per plant. In order to solve the problem, research has been done to know the effect of plant growth regulator on the growth and red onion production from TSS and also get the description of red onion farming from TSS and tuber as seed source. The research was conducted from June to November 2017 at BPP Pare, Kediri Regency, East Java. The results showed that the use of young coconut water on TSS obtained red onion plants are able to produce the number of tubers per plant more than 3 cloves. In detail as much as 22.22 % produces the number of tubers range 4-5 per plant; 56.56 % yields 5-6 bulb range; and as much as 22.22 % produces tubers > 6. As well, wet weight of tubers when harvested weighing more than 99 g per plant. If converted per hectare, TSS red onion plants treated with young coconut water can produce a range of 30 -35 tons of wet bulb. This production is doubled compared to the production of shallots grown from tubers. Based on the analysis of the farm, red onion from TSS treated with young coconut water gives a profit of Rp 224,860,000 per hectare with B/C ratio of 3.397. This profit is more than 1.75 times compared to the profit of red onion tuber farming which is only Rp 93.787.000, - with B

  18. GABA signalling modulates plant growth by directly regulating the activity of plant-specific anion transporters.

    Science.gov (United States)

    Ramesh, Sunita A; Tyerman, Stephen D; Xu, Bo; Bose, Jayakumar; Kaur, Satwinder; Conn, Vanessa; Domingos, Patricia; Ullah, Sana; Wege, Stefanie; Shabala, Sergey; Feijó, José A; Ryan, Peter R; Gilliham, Matthew; Gillham, Matthew

    2015-07-29

    The non-protein amino acid, gamma-aminobutyric acid (GABA) rapidly accumulates in plant tissues in response to biotic and abiotic stress, and regulates plant growth. Until now it was not known whether GABA exerts its effects in plants through the regulation of carbon metabolism or via an unidentified signalling pathway. Here, we demonstrate that anion flux through plant aluminium-activated malate transporter (ALMT) proteins is activated by anions and negatively regulated by GABA. Site-directed mutagenesis of selected amino acids within ALMT proteins abolishes GABA efficacy but does not alter other transport properties. GABA modulation of ALMT activity results in altered root growth and altered root tolerance to alkaline pH, acid pH and aluminium ions. We propose that GABA exerts its multiple physiological effects in plants via ALMT, including the regulation of pollen tube and root growth, and that GABA can finally be considered a legitimate signalling molecule in both the plant and animal kingdoms.

  19. Biotechnological application and taxonomical distribution of plant growth promoting actinobacteria.

    Science.gov (United States)

    Hamedi, Javad; Mohammadipanah, Fatemeh

    2015-02-01

    Plant growth promoting (PGP) bacteria are involved in various interactions known to affect plant fitness and soil quality, thereby increasing the productivity of agriculture and stability of soil. Although the potential of actinobacteria in antibiotic production is well-investigated, their capacity to enhance plant growth is not fully surveyed. Due to the following justifications, PGP actinobacteria (PGPA) can be considered as a more promising taxonomical group of PGP bacteria: (1) high numbers of actinobacteria per gram of soil and their filamentous nature, (2) genome dedicated to the secondary metabolite production (~5 to 10 %) is distinctively more than that of other bacteria and (3) number of plant growth promoter genera reported from actinobacteria is 1.3 times higher than that of other bacteria. Mechanisms by which PGPA contribute to the plant growth by association are: (a) enhancing nutrients availability, (b) regulation of plant metabolism, (c) decreasing environmental stress, (d) control of phytopathogens and (e) improvement of soil texture. Taxonomical and chemical diversity of PGPA and their biotechnological application along with their associated challenges are summarized in this paper.

  20. Microbiome selection could spur next-generation plant breeding strategies

    Directory of Open Access Journals (Sweden)

    Murali Gopal

    2016-12-01

    Full Text Available Plants, though sessile, have developed a unique strategy to counter biotic and abiotic stresses by symbiotically co-evolving with microorganisms and tapping into their genome for this purpose. Soil is the bank of microbial diversity from which a plant selectively sources its microbiome to suit its needs. Besides soil, seeds, which carry the genetic blueprint of plants during trans-generational propagation, are home to diverse microbiota that acts as the principal source of microbial inoculum in crop cultivation. Overall, a plant is ensconced both on the outside and inside with a diverse assemblage of microbiota. Together, the plant genome and the genes of the microbiota that the plant harbours in different plant tissues i.e the ‘plant microbiome’, form the holobiome which is now considered as unit of selection: ‘the holobiont’. The ‘plant microbiome’ not only helps plants to remain fit but also offers critical genetic variability, hitherto, not employed in the breeding strategy by plant breeders, who traditionally have exploited the genetic variability of the host for developing high yielding or disease tolerant or drought resistant varieties. This fresh knowledge of the microbiome, particularly of the rhizosphere, offering genetic variability to plants, opens up new horizons for breeding that could usher in cultivation of next-generation crops depending less on inorganic inputs, resistant to insect pest and diseases and resilient to climatic perturbations. We surmise, from ever increasing evidences, that plants and their microbial symbionts need to be co-propagated as life-long partners in future strategies for plant breeding.

  1. Synergistic use of biochar, compost and plant growth-promoting rhizobacteria for enhancing cucumber growth under water deficit conditions.

    Science.gov (United States)

    Nadeem, Sajid M; Imran, Muhammad; Naveed, Muhammad; Khan, Muhammad Y; Ahmad, Maqshoof; Zahir, Zahir A; Crowley, David E

    2017-12-01

    Limited information is available about the effectiveness of biochar with plant growth-promoting rhizobacteria (PGPR) and compost. A greenhouse study was conducted to evaluate the effect of biochar in combination with compost and PGPR (Pseudomonas fluorescens) for alleviating water deficit stress. Both inoculated and un-inoculated cucumber seeds were sown in soil treated with biochar, compost and biochar + compost. Three water levels - field capacity (D0), 75% field capacity (D1) and 50% field capacity (D2) - were maintained. The results showed that water deficit stress significantly suppressed the growth of cucumber; however, synergistic use of biochar, compost and PGPR mitigated the negative impact of stress. At D2, the synergistic use of biochar, compost and PGPR caused significant increases in shoot length, shoot biomass, root length and root biomass, which were respectively 88, 77, 89 and 74% more than in the un-inoculated control. Significant improvements in chlorophyll and relative water contents as well as reduction in leaf electrolyte leakage demonstrated the effectiveness of this approach. Moreover, the highest population of P. fluorescens was observed where biochar and compost were applied together. These results suggest that application of biochar with PGPR and/or compost could be an effective strategy for enhancing plant growth under stress. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  2. Peat soil composition as indicator of plants growth environment

    Science.gov (United States)

    Noormets, M.; Tonutare, T.; Kauer, K.; Szajdak, L.; Kolli, R.

    2009-04-01

    Exhausted milled peat areas have been left behind as a result of decades-lasting intensive peat production in Estonia and Europe. According to different data there in Estonia is 10 000 - 15 000 ha of exhausted milled peat areas that should be vegetated. Restoration using Sphagnum species is most advantageous, as it creates ecological conditions closest to the natural succession towards a natural bog area. It is also thought that the large scale translocation of vegetation from intact bogs, as used in some Canadian restoration trials, is not applicable in most of European sites due to limited availability of suitable donor areas. Another possibility to reduce the CO2 emission in these areas is their use for cultivation of species that requires minimum agrotechnical measures exploitation. It is found by experiments that it is possible to establish on Vaccinium species for revegetation of exhausted milled peat areas. Several physiological activity of the plant is regulated by the number of phytohormones. These substances in low quantities move within the plant from a site of production to a site of action. Phytohormone, indole-3-acetic acid (IAA) is formed in soils from tryptophane by enzymatic conversion. This compound seems to play an important function in nature as result to its influence in regulation of plant growth and development. A principal feature of IAA is its ability to affect growth, development and health of plants. This compound activates root morphology and metabolic changes in the host plant. The physiological impact of this substance is involved in cell elongation, apical dominance, root initiation, parthenocarpy, abscission, callus formation and the respiration. The investigation areas are located in the county of Tartu (58˚ 22' N, 26˚ 43' E), in the southern part of Estonia. The soil of the experimental fields belongs according to the WRB soil classification, to the soils subgroups of Fibri-Dystric Histosols. The investigation areas were

  3. Increasing plant growth by modulating omega-amidase expression in plants

    Science.gov (United States)

    Unkefer, Pat J.; Anderson, Penelope S.; Knight, Thomas J.

    2015-06-30

    The present disclosure relates to compositions and methods for increasing the leaf-to-root ratio of the signal metabolite 2-oxoglutaramate and related proline molecules in plants by modulating levels of .omega.-amidase to increase nitrogen use efficiency, resulting in enhanced growth, faster growth rates, greater seed and fruit/pod yields, earlier and more productive flowering, increased tolerance to high salt conditions, and increased biomass yields.

  4. Compatible bacterial mixture, tolerant to desiccation, improves maize plant growth.

    Science.gov (United States)

    Molina-Romero, Dalia; Baez, Antonino; Quintero-Hernández, Verónica; Castañeda-Lucio, Miguel; Fuentes-Ramírez, Luis Ernesto; Bustillos-Cristales, María Del Rocío; Rodríguez-Andrade, Osvaldo; Morales-García, Yolanda Elizabeth; Munive, Antonio; Muñoz-Rojas, Jesús

    2017-01-01

    Plant growth-promoting rhizobacteria (PGPR) increase plant growth and crop productivity. The inoculation of plants with a bacterial mixture (consortium) apparently provides greater benefits to plant growth than inoculation with a single bacterial strain. In the present work, a bacterial consortium was formulated containing four compatible and desiccation-tolerant strains with potential as PGPR. The formulation had one moderately (Pseudomonas putida KT2440) and three highly desiccation-tolerant (Sphingomonas sp. OF178, Azospirillum brasilense Sp7 and Acinetobacter sp. EMM02) strains. The four bacterial strains were able to adhere to seeds and colonize the rhizosphere of plants when applied in both mono-inoculation and multi-inoculation treatments, showing that they can also coexist without antagonistic effects in association with plants. The effects of the bacterial consortium on the growth of blue maize were evaluated. Seeds inoculated with either individual bacterial strains or the bacterial consortium were subjected to two experimental conditions before sowing: normal hydration or desiccation. In general, inoculation with the bacterial consortium increased the shoot and root dry weight, plant height and plant diameter compared to the non-inoculated control or mono-inoculation treatments. The bacterial consortium formulated in this work had greater benefits for blue maize plants even when the inoculated seeds underwent desiccation stress before germination, making this formulation attractive for future field applications.

  5. Compatible bacterial mixture, tolerant to desiccation, improves maize plant growth.

    Directory of Open Access Journals (Sweden)

    Dalia Molina-Romero

    Full Text Available Plant growth-promoting rhizobacteria (PGPR increase plant growth and crop productivity. The inoculation of plants with a bacterial mixture (consortium apparently provides greater benefits to plant growth than inoculation with a single bacterial strain. In the present work, a bacterial consortium was formulated containing four compatible and desiccation-tolerant strains with potential as PGPR. The formulation had one moderately (Pseudomonas putida KT2440 and three highly desiccation-tolerant (Sphingomonas sp. OF178, Azospirillum brasilense Sp7 and Acinetobacter sp. EMM02 strains. The four bacterial strains were able to adhere to seeds and colonize the rhizosphere of plants when applied in both mono-inoculation and multi-inoculation treatments, showing that they can also coexist without antagonistic effects in association with plants. The effects of the bacterial consortium on the growth of blue maize were evaluated. Seeds inoculated with either individual bacterial strains or the bacterial consortium were subjected to two experimental conditions before sowing: normal hydration or desiccation. In general, inoculation with the bacterial consortium increased the shoot and root dry weight, plant height and plant diameter compared to the non-inoculated control or mono-inoculation treatments. The bacterial consortium formulated in this work had greater benefits for blue maize plants even when the inoculated seeds underwent desiccation stress before germination, making this formulation attractive for future field applications.

  6. Loblolly pine seedling growth after inoculation with plant growth-promoting rhizobacteria and ozone exposure

    Energy Technology Data Exchange (ETDEWEB)

    Estes, B.L.; Enebak, S.A.; Chappelka, A.H. [Auburn Univ., Auburn, AL (United States). School of Forestry and Wildlife Sciences

    2004-07-01

    The conifer tree species with the greatest economic importance in south eastern United States plantations is Loblolly pine. Plantations require intensive fertilization, pesticide application, and irrigation. In these cases growth-promoting rhizobacteria are useful in pest control. While it was once thought that ozone in the troposphere was limited to urban areas, it is now known that it is transported far from its place of origin. Ozone is known to impact plant growth negatively. There have been no previous studies on whether growth-promoting rhizobacteria can decrease the negative effects of ozone. In this study seedlings of Loblolly pine were inoculated with either Bacillus subtilis (Ehrenberg) Cohn or Paenibacillus macerans (Schardinger) Ash. These were exposed to controlled amounts of ozone for 8-12 weeks. All plants showed decreased biomass and increased foliar damage compared to plants that were not exposed to ozone. B. subtilis inoculated plants showed less foliar damage than un-inoculated ones and root dimensions were increased. The use of growth-promoting rhizobacteria is not ready for large-scale commercial application in forestry, but this demonstration of the possible beneficial effects on ozone exposure warrants further investigation. 44 refs., 3 tabs., 2 figs.

  7. Usage and control of solid-state lighting for plant growth

    Energy Technology Data Exchange (ETDEWEB)

    Pinho, P.

    2008-07-01

    The work begins with an introductory part in which the basic aspects related to the photosynthetic radiation, the photobiology of plants and the technology of light-emitting diodes (Leads) are overviewed. It is followed by a review of related research works that have been conducted during the last two decades, and by the main design issues of Led lumin aires for plant growth. The following part of the work reports the experimental growth tests performed. The effects of the radiation emitted by spectrally tailored Led lumin aires on plant growth have been investigated. A total of four growth tests using lettuce and radish cultivars were performed. Two basic approaches were used to investigate the effects and the future possibilities of the usage of solid-state lighting (SSL) in plant growth. The first approach evaluates the growth development of lettuce plants in real greenhouse conditions using LEDs as supplementary light sources to natural daylight. In the second approach the evaluation was carried out with a total absence of natural daylight by growing lettuce and radish plants in phytotron-chamber conditions. The effects of SSL treatments on the growth development and quality of crops were compared with reference lighting systems composed of conventional and well-established light-source technologies, such as fluorescent and high-pressure sodium lamps. During the process of the investigation, the need to coherently quantify and evaluate the spectral quality of the radiation in terms of its photosynthetic appetence arose. Different metrics are still been used indiscriminately to quantify radiation used by plants to perform photosynthesis. Therefore, the existing metrics are discussed and a new proposal for coherent systematization is presented. The proposed system is referred to phyllophotometric and it is developed using the average photosynthetic spectral quantum yield response curve of plants. The results of the growth tests showed that the usage of SSL in

  8. Role of Plant Growth Promoting Rhizobacteria in Agricultural Sustainability—A Review

    Directory of Open Access Journals (Sweden)

    Pravin Vejan

    2016-04-01

    Full Text Available Plant growth promoting rhizobacteria (PGPR shows an important role in the sustainable agriculture industry. The increasing demand for crop production with a significant reduction of synthetic chemical fertilizers and pesticides use is a big challenge nowadays. The use of PGPR has been proven to be an environmentally sound way of increasing crop yields by facilitating plant growth through either a direct or indirect mechanism. The mechanisms of PGPR include regulating hormonal and nutritional balance, inducing resistance against plant pathogens, and solubilizing nutrients for easy uptake by plants. In addition, PGPR show synergistic and antagonistic interactions with microorganisms within the rhizosphere and beyond in bulk soil, which indirectly boosts plant growth rate. There are many bacteria species that act as PGPR, described in the literature as successful for improving plant growth. However, there is a gap between the mode of action (mechanism of the PGPR for plant growth and the role of the PGPR as biofertilizer—thus the importance of nano-encapsulation technology in improving the efficacy of PGPR. Hence, this review bridges the gap mentioned and summarizes the mechanism of PGPR as a biofertilizer for agricultural sustainability.

  9. Role of Plant Growth Promoting Rhizobacteria in Agricultural Sustainability-A Review.

    Science.gov (United States)

    Vejan, Pravin; Abdullah, Rosazlin; Khadiran, Tumirah; Ismail, Salmah; Nasrulhaq Boyce, Amru

    2016-04-29

    Plant growth promoting rhizobacteria (PGPR) shows an important role in the sustainable agriculture industry. The increasing demand for crop production with a significant reduction of synthetic chemical fertilizers and pesticides use is a big challenge nowadays. The use of PGPR has been proven to be an environmentally sound way of increasing crop yields by facilitating plant growth through either a direct or indirect mechanism. The mechanisms of PGPR include regulating hormonal and nutritional balance, inducing resistance against plant pathogens, and solubilizing nutrients for easy uptake by plants. In addition, PGPR show synergistic and antagonistic interactions with microorganisms within the rhizosphere and beyond in bulk soil, which indirectly boosts plant growth rate. There are many bacteria species that act as PGPR, described in the literature as successful for improving plant growth. However, there is a gap between the mode of action (mechanism) of the PGPR for plant growth and the role of the PGPR as biofertilizer-thus the importance of nano-encapsulation technology in improving the efficacy of PGPR. Hence, this review bridges the gap mentioned and summarizes the mechanism of PGPR as a biofertilizer for agricultural sustainability.

  10. Effect of plant growth promoting rhizobacteria on root morphology of ...

    African Journals Online (AJOL)

    Jane

    2011-10-03

    Oct 3, 2011 ... Plant growth promoting rhizobacteria improve the plant growth by a variety of ways like ... preparing textile dye in the Far East, Central and. Northern Asia and ... The experiment was carried out in complete randomized design.

  11. Laboratory study on influence of plant growth promoting ...

    African Journals Online (AJOL)

    Aghomotsegin

    2015-03-06

    Mar 6, 2015 ... promoting rhizobacteria (PGPR) on growth response and tolerance of Zea ... inoculating maize seeds with plant growth promoting rhizobacterial strains in a crude oil impacted medium. ..... Botany and Environmental Health.

  12. Nickel detoxification and plant growth promotion by multi metal resistant plant growth promoting Rhizobium species RL9.

    Science.gov (United States)

    Wani, Parvaze Ahmad; Khan, Mohammad Saghir

    2013-07-01

    Pollution of the biosphere by heavy metals is a global threat that has accelerated dramatically since the beginning of industrial revolution. The aim of the study is to check the resistance of RL9 towards the metals and to observe the effect of Rhizobium species on growth, pigment content, protein and nickel uptake by lentil in the presence and absence of nickel. The multi metal tolerant and plant growth promoting Rhizobium strain RL9 was isolated from the nodules of lentil. The strain not only tolerated nickel but was also tolerant o cadmium, chromium, nickel, lead, zinc and copper. The strain tolerated nickel 500 μg/mL, cadmium 300 μg/mL, chromium 400 μg/mL, lead 1,400 μg/mL, zinc 1,000 μg/mL and copper 300 μg/mL, produced good amount of indole acetic acid and was also positive for siderophore, hydrogen cyanide and ammonia. The strain RL9 was further assessed with increasing concentrations of nickel when lentil was used as a test crop. The strain RL9 significantly increased growth, nodulation, chlorophyll, leghaemoglobin, nitrogen content, seed protein and seed yield compared to plants grown in the absence of bioinoculant but amended with nickel The strain RL9 decreased uptake of nickel in lentil compared to plants grown in the absence of bio-inoculant. Due to these intrinsic abilities strain RL9 could be utilized for growth promotion as well as for the remediation of nickel in nickel contaminated soil.

  13. Getting the ecology into the interactions between plants and the plant-growth promoting bacterium Pseudomonas fluorescens

    NARCIS (Netherlands)

    Hol, W.H.G.; Bezemer, T.M.; Biere, A.

    2013-01-01

    Plant growth-promoting rhizobacteria (PGPR) are increasingly appreciated for their contributions to primary productivity through promotion of growth and triggering of induced systemic resistance in plants. Here we focus on the beneficial effects of one particular species of PGPR (Pseudomonas

  14. Short-Chain Chitin Oligomers: Promoters of Plant Growth

    Directory of Open Access Journals (Sweden)

    Alexander J. Winkler

    2017-02-01

    Full Text Available Chitin is the second most abundant biopolymer in nature after cellulose, and it forms an integral part of insect exoskeletons, crustacean shells, krill and the cell walls of fungal spores, where it is present as a high-molecular-weight molecule. In this study, we showed that a chitin oligosaccharide of lower molecular weight (tetramer induced genes in Arabidopsis that are principally related to vegetative growth, development and carbon and nitrogen metabolism. Based on plant responses to this chitin tetramer, a low-molecular-weight chitin mix (CHL enriched to 92% with dimers (2mer, trimers (3mer and tetramers (4mer was produced for potential use in biotechnological processes. Compared with untreated plants, CHL-treated plants had increased in vitro fresh weight (10%, radicle length (25% and total carbon and nitrogen content (6% and 8%, respectively. Our data show that low-molecular-weight forms of chitin might play a role in nature as bio-stimulators of plant growth, and they are also a known direct source of carbon and nitrogen for soil biomass. The biochemical properties of the CHL mix might make it useful as a non-contaminating bio-stimulant of plant growth and a soil restorer for greenhouses and fields.

  15. Enhanced shoot investment makes invasive plants exhibit growth advantages in high nitrogen conditions.

    Science.gov (United States)

    Liu, X A; Peng, Y; Li, J J; Peng, P H

    2018-03-12

    Resource amendments commonly promote plant invasions, raising concerns over the potential consequences of nitrogen (N) deposition; however, it is unclear whether invaders will benefit from N deposition more than natives. Growth is among the most fundamental inherent traits of plants and thus good invaders may have superior growth advantages in response to resource amendments. We compared the growth and allocation between invasive and native plants in different N regimes including controls (ambient N concentrations). We found that invasive plants always grew much larger than native plants in varying N conditions, regardless of growth- or phylogeny-based analyses, and that the former allocated more biomass to shoots than the latter. Although N addition enhanced the growth of invasive plants, this enhancement did not increase with increasing N addition. Across invasive and native species, changes in shoot biomass allocation were positively correlated with changes in whole-plant biomass; and the slope of this relationship was greater in invasive plants than native plants. These findings suggest that enhanced shoot investment makes invasive plants retain a growth advantage in high N conditions relative to natives, and also highlight that future N deposition may increase the risks of plant invasions.

  16. High-yielding Wheat Varieties Harbour Superior Plant Growth Promoting-Bacterial Endophytes

    Directory of Open Access Journals (Sweden)

    Mehwish Yousaf

    2017-06-01

    Full Text Available Background and Objective: The purpose of this study was to compare the endophytic microbial flora of different wheat varieties to check whether a better yielding variety also harbours superior plant growth promoting bacteria. Such bacteria are helpful in food biotechnology as their application can enhance the yield of the crop.Material and Methods: Three wheat varieties (Seher, Faisalabad and Lasani were selected, Seher being the most superior variety. endophytic bacteria were isolated from the histosphere of the leaves and roots at different growth phases of the plants. The isolates were analyzed for plant growth promoting activities. Isolates giving best results were identified through 16S rRNA gene sequencing. Statistical analysis was done using Microsoft Excel 2013. All the experiments were conducted in triplicates.Results and Conclusion: The endophytes of Seher variety showed maximum plant growth promoting abilities. Among the shoot endophytes, the highest auxin production was shown by Seher isolate SHHP1-3 up to 51.9μg ml-1, whereas in the case of root endophytes, the highest auxin was produced by SHHR1-5 up to 36 μg ml-1. The bacteria showing significant plant growth promoting abilities were identified by 16S rRNA sequencing. Bacillus, Proteobacteria and Actinobacteria species were the dominant bacteria showing all the traits of plant growth promotion. It can be concluded that Seher variety harbours superior plant growth promoting endophytes that must be one of the reasons for its better growth and yield as compared to the other two varieties. The investigated results support possible utilization of the selected isolates in wheat growth promotion with respect to increase in agro-productivity. The application of such bacteria could be useful to enhance wheat yield and can help in food biotechnology.Conflict of interest: The authors declare no conflict of interest.

  17. Bacillus spp. from rainforest soil promote plant growth under limited nitrogen conditions.

    Science.gov (United States)

    Huang, X-F; Zhou, D; Guo, J; Manter, D K; Reardon, K F; Vivanco, J M

    2015-03-01

    The aim of this study was to evaluate effects of PGPR (plant growth-promoting rhizobacteria) isolated from rainforest soil on different plants under limited nitrogen conditions. Bacterial isolates from a Peruvian rainforest soil were screened for plant growth-promoting effects on Arabidopsis (Col-0). Four selected isolates including one Bacillus subtilis, two B. atrophaeus and one B. pumilus significantly promoted growth of Zea mays L. and Solanum lycopersicum under greenhouse conditions. Moreover, the PGPRs significantly promoted growth of S. lycopersicum in both low and nitrogen-amended soil conditions. These PGPR strains were further studied to obtain insights into possible mechanisms of plant growth promotion. Volatile chemicals from those isolates promoted Arabidopsis growth, and the expression of genes related to IAA production was induced in the Arabidopsis plants treated with PGPRs. Further, selected PGPR strains triggered induced systemic resistance (ISR) against Pseudomonas syringae pv tomato DC3000 in Arabidopsis. PGPR strains isolated from the rainforest soil promoted the plant growth of Arabidopsis, corn and tomato. New PGPR that have wider adaptability to different crops, soils and environmental conditions are needed to decrease our reliance on agricultural amendments derived from fossil-based fuels. The PGPRs isolated from a nonagricultural site constitute new plant growth-promoting strains that could be developed for agricultural uses. © 2014 The Society for Applied Microbiology.

  18. GROWTH STRATEGIES OF MULTINATIONAL COMPANIES STUDY CASE: PRECIOUS METALS JEWELRY RETAIL INDUSTRY

    Directory of Open Access Journals (Sweden)

    Raluca Daniela RIZEA

    2015-04-01

    Full Text Available The turbulent start of the new century has brought new challenges for firms, industries and countries. This paper investigates business and growth strategies of multinational companies within the precious metals jewelry retail industry. The main objective is to identify whether a company’s performance is determined by its growth strategy or not. The purposes for the research are: to understand what kind of business models and strategies global precious metals jewelry retailers pursue, what growth strategies global jewelry retailers pursue and if there is a link between a company’s growth strategy and its profitability. Least but not last, the findings are reviewed on their transferability to other industries. The findings regarding the business models and growth strategies pursued are that all of them are based on Porter’s generic strategies as well as internationalization and diversification but there is no specific preference given to any of the strategic elements.

  19. The role of endomembrane-localized VHA-c in plant growth.

    Science.gov (United States)

    Zhou, Aimin; Takano, Tetsuo; Liu, Shenkui

    2018-01-02

    In plant cells, the vacuolar-type H + -ATPase (V-ATPase), a large multis`ubunit endomembrane proton pump, plays an important role in acidification of subcellular organelles, pH and ion homeostasis, and endocytic and secretory trafficking. V-ATPase subunit c (VHA-c) is essential for V-ATPase assembly, and is directly responsible for binding and transmembrane transport of protons. In previous studies, we identified a PutVHA-c gene from Puccinellia tenuiflora, and investigated its function in plant growth. Subcellular localization revealed that PutVHA-c is mainly localized in endosomal compartments. Overexpression of PutVHA-c enhanced V-ATPase activity and promoted plant growth in transgenic Arabidopsis. Furthermore, the activity of V-ATPase affected intracellular transport of the Golgi-derived endosomes. Our results showed that endomembrane localized-VHA-c contributes to plant growth by influencing V-ATPase-dependent endosomal trafficking. Here, we discuss these recent findings and speculate on the VHA-c mediated molecular mechanisms involved in plant growth, providing a better understanding of the functions of VHA-c and V-ATPase.

  20. The vascular plants: open system of growth.

    Science.gov (United States)

    Basile, Alice; Fambrini, Marco; Pugliesi, Claudio

    2017-03-01

    What is fascinating in plants (true also in sessile animals such as corals and hydroids) is definitely their open and indeterminate growth, as a result of meristematic activity. Plants as well as animals are characterized by a multicellular organization, with which they share a common set of genes inherited from a common eukaryotic ancestor; nevertheless, circa 1.5 billion years of evolutionary history made the two kingdoms very different in their own developmental biology. Flowering plants, also known as angiosperms, arose during the Cretaceous Period (145-65 million years ago), and up to date, they count around 235,000 species, representing the largest and most diverse group within the plant kingdom. One of the foundations of their success relies on the plant-pollinator relationship, essentially unique to angiosperms that pushed large speciation in both plants and insects and on the presence of the carpel, the structure devoted to seed enclosure. A seed represents the main organ preserving the genetic information of a plant; during embryogenesis, the primary axis of development is established by two groups of pluripotent cells: the shoot apical meristem (SAM), responsible for gene rating all aboveground organs, and the root apical meristem (RAM), responsible for producing all underground organs. During postembryonic shoot development, axillary meristem (AM) initiation and outgrowth are responsible for producing all secondary axes of growth including inflorescence branches or flowers. The production of AMs is tightly linked to the production of leaves and their separation from SAM. As leaf primordia are formed on the flanks of the SAM, a region between the apex and the developing organ is established and referred to as boundary zone. Interaction between hormones and the gene network in the boundary zone is fundamental for AM initiation. AMs only develop at the adaxial base of the leaf; thus, AM initiation is also strictly associated with leaf polarity. AMs

  1. Conditions for Growth of Plants

    NARCIS (Netherlands)

    Sandercock, P.; Hooke, J.; Barberá, M.; Navarro-Cano, J.A.; Querejeta, J.I.; Lesschen, J.P.; Cammeraat, L.H.; Meerkerk, A.; van Wesemael, B.; De Baets, S.; Poesen, J.; Hooke, J.; Sandercock, P.

    2017-01-01

    This chapter sets out the approach and research methods used to assess the plant types and species that grow in different parts of the targeted Mediterranean landscape and that could potentially be used in restoration strategies and mitigation of desertified and degraded land. Species occurring in

  2. Characterization of Minnesota lunar simulant for plant growth

    Science.gov (United States)

    Oglesby, James P.; Lindsay, Willard L.; Sadeh, Willy Z.

    1993-01-01

    Processing of lunar regolith into a plant growth medium is crucial in the development of a regenerative life support system for a lunar base. Plants, which are the core of such a system, produce food and oxygen for humans and, at the same time, consume carbon dioxide. Because of the scarcity of lunar regolith, simulants must be used to infer its properties and to develop procedures for weathering and chemical analyses. The Minnesota Lunar Simulant (MLS) has been identified to date as the best available simulant for lunar regolith. Results of the dissolution studies reveal that appropriately fertilized MLS can be a suitable medium for plant growth. The techniques used in conducting these studies can be extended to investigate the suitability of actual lunar regolith as a plant growth medium. Dissolution experiments were conducted using the MLS to determine its nutritional and toxicity characteristics for plant growth and to develop weathering and chemical analysis techniques. Two weathering regimes, one with water and one with dilute organic acids simulating the root rhizosphere microenvironment, were investigated. Elemental concentrations were measured using inductively-coupled-plasma (ICP) emission spectrometry and ion chromatography (IC). The geochemical speciation model, MINTEQA2, was used to determine the major solution species and the minerals controlling them. Acidification was found to be a useful method for increasing cation concentrations to meaningful levels. Initial results indicate that MLS weathers to give neutral to slightly basic solutions which contain acceptable amounts of the essential elements required for plant nutrition (i.e., potassium, calcium, magnesium, sulfur, zinc, sodium, silicon, manganese, copper, chlorine, boron, molybdenum, and cobalt). Elements that need to be supplemented include carbon, nitrogen, and perhaps phosphorus and iron. Trace metals in solution were present at nontoxic levels.

  3. Plant growth promoters and methods of using them

    KAUST Repository

    Al-Babili, Salim

    2017-01-01

    New plant growth regulators, including compounds and compositions, and methods of use including for promoting root growth. The compounds are carotenoid oxidation products, and a preferred example is 3-OH--β-apo-13-Carotenone. A method comprising

  4. Selenium promotes sulfur accumulation and plant growth in wheat (Triticum aestivum)

    Science.gov (United States)

    Selenium (Se) is an essential micronutrient for animals and humans and a target for biofortification in crops. Sulfur (S) is a crucial nutrient for plant growth. To gain better understanding of Se and S nutrition and interaction in plants, the effects of Se dosages and forms on plant growth as well ...

  5. Sugar signals and the control of plant growth and development

    NARCIS (Netherlands)

    Lastdrager, Jeroen|info:eu-repo/dai/nl/357520076; Hanson, Johannes|info:eu-repo/dai/nl/304822299; Smeekens, Sjef|info:eu-repo/dai/nl/072489995

    2014-01-01

    Sugars have a central regulatory function in steering plant growth. This review focuses on information presented in the past 2 years on key players in sugar-mediated plant growth regulation, with emphasis on trehalose 6-phosphate, target of rapamycin kinase, and Snf1-related kinase 1 regulatory

  6. Lactococcus lactis Metabolism and Gene Expression during Growth on Plant Tissues

    Science.gov (United States)

    Golomb, Benjamin L.

    2014-01-01

    Lactic acid bacteria have been isolated from living, harvested, and fermented plant materials; however, the adaptations these bacteria possess for growth on plant tissues are largely unknown. In this study, we investigated plant habitat-specific traits of Lactococcus lactis during growth in an Arabidopsis thaliana leaf tissue lysate (ATL). L. lactis KF147, a strain originally isolated from plants, exhibited a higher growth rate and reached 7.9-fold-greater cell densities during growth in ATL than the dairy-associated strain L. lactis IL1403. Transcriptome profiling (RNA-seq) of KF147 identified 853 induced and 264 repressed genes during growth in ATL compared to that in GM17 laboratory culture medium. Genes induced in ATL included those involved in the arginine deiminase pathway and a total of 140 carbohydrate transport and metabolism genes, many of which are involved in xylose, arabinose, cellobiose, and hemicellulose metabolism. The induction of those genes corresponded with L. lactis KF147 nutrient consumption and production of metabolic end products in ATL as measured by gas chromatography-time of flight mass spectrometry (GC-TOF/MS) untargeted metabolomic profiling. To assess the importance of specific plant-inducible genes for L. lactis growth in ATL, xylose metabolism was targeted for gene knockout mutagenesis. Wild-type L. lactis strain KF147 but not an xylA deletion mutant was able to grow using xylose as the sole carbon source. However, both strains grew to similarly high levels in ATL, indicating redundancy in L. lactis carbohydrate metabolism on plant tissues. These findings show that certain strains of L. lactis are well adapted for growth on plants and possess specific traits relevant for plant-based food, fuel, and feed fermentations. PMID:25384484

  7. Influence of Plant Growth Regulators (PGRs and Planting Method on Growth and Yield in Oil Pumpkin (Cucurbita pepo var. styriaca

    Directory of Open Access Journals (Sweden)

    Shirzad SURE

    2012-05-01

    Full Text Available The effect of plant growth regulators IBA (indole butyric acid, GA3 (gibberellin and ethylene (as ethephon in two methods of planting was investigated (each method was considered as a separate experiment on morphological characters and yield of medicinal pumpkin. The experiments were carried out in a factorial trial based on completely randomized block design, with four replicates. The treatments were combined with priming and spraying with the above PGRs. The first seed priming with control (water, IBA 100 ppm, GA3 25 ppm and ethephon 200 ppm, and when seedling developed to 4 leaf stage sprayed there with control (water, IBA 100 ppm, GA3 25 ppm and ethephon 200 ppm for three times. In both planting methods, there were all of these treatments. The result showed that PGRs and planting method had significant effects on vegetative, flowering and yield characteristics including: leaf area %DM plant, number of male and female flowers per plant, number of fruit/plant, fruits fresh weight, seeds length and width, number of seed per fruit, seed yield, % seeds oil and oil yield. Hence spraying with GA3 25 ppm in four leaf stage at trellis method could be a suitable treatment for enhancing growth and yield of medicinal pumpkin.

  8. Contrasting Strategies of Alfalfa Stem Elongation in Response to Fall Dormancy in Early Growth Stage: The Tradeoff between Internode Length and Internode Number

    Science.gov (United States)

    Wang, Zongli; Sun, Qizhong

    2015-01-01

    Fall dormancy (FD) in alfalfa (Medicago sativa L.) can be described using 11 FD ratings, is widely used as an important indicator of stress resistance, productive performance and spring growth. However, the contrasting growth strategies in internode length and internode number in alfalfa cultivars with different FD rating are poorly understood. Here, a growth chamber study was conducted to investigate the effect of FD on plant height, aboveground biomass, internode length, and internode number in alfalfa individuals in the early growth stages. In order to simulate the alfalfa growth environment in the early stage, 11 alfalfa cultivars with FD ratings from one to 11 were chosen and seeded at the greenhouse, and then were transplanted into an artificial growth chamber. The experimental design was a randomized complete block in a split-plot arrangement with three replicates. Plant height, above-ground biomass, internode length, and internode number were measured in early growth stage in all individuals. Our findings showed that plant height and the aboveground biomass of alfalfa did not significantly differ among 11 different FD rated cultivars. Also, internode length and internode number positively affected plant height and the aboveground biomass of alfalfa individuals and the average internode length significantly increased with increasing FD rating. However, internode number tended to sharply decline when the FD rating increased. Moreover, there were no correlations, slightly negative correlations, and strongly negative correlations between internode length and internode number in alfalfa individuals among the three scales, including within-FD ratings, within-FD categories and inter-FD ratings, respectively. Therefore, our results highlighted that contrasting growth strategies in stem elongation were adopted by alfalfa with different FD ratings in the early growth stage. Alfalfa cultivars with a high FD rating have longer internodes, whereas more dormant alfalfa

  9. Benchmarking of Control Strategies for Wastewater Treatment Plants

    DEFF Research Database (Denmark)

    Wastewater treatment plants are large non-linear systems subject to large perturbations in wastewater flow rate, load and composition. Nevertheless these plants have to be operated continuously, meeting stricter and stricter regulations. Many control strategies have been proposed in the literature...

  10. Individualism in plant populations: using stochastic differential equations to model individual neighbourhood-dependent plant growth.

    Science.gov (United States)

    Lv, Qiming; Schneider, Manuel K; Pitchford, Jonathan W

    2008-08-01

    We study individual plant growth and size hierarchy formation in an experimental population of Arabidopsis thaliana, within an integrated analysis that explicitly accounts for size-dependent growth, size- and space-dependent competition, and environmental stochasticity. It is shown that a Gompertz-type stochastic differential equation (SDE) model, involving asymmetric competition kernels and a stochastic term which decreases with the logarithm of plant weight, efficiently describes individual plant growth, competition, and variability in the studied population. The model is evaluated within a Bayesian framework and compared to its deterministic counterpart, and to several simplified stochastic models, using distributional validation. We show that stochasticity is an important determinant of size hierarchy and that SDE models outperform the deterministic model if and only if structural components of competition (asymmetry; size- and space-dependence) are accounted for. Implications of these results are discussed in the context of plant ecology and in more general modelling situations.

  11. Effect of plant-growth-promoting rhizobacteria inoculation on plant ...

    African Journals Online (AJOL)

    A field experiment was conducted in a wet season (Kharif) to study the effects of plant growth-promoting rhizobacteria(PGPR) inoculation on agronomic traits and productivity of Basmati rice (cv. 'Pusa Basmati 1401') in a randomized block with twelve treatments. We evaluated one bacterial (Providencia sp. PW5) and one ...

  12. Symbiotic regulation of plant growth, development and reproduction

    Science.gov (United States)

    Rodriguez, R.J.; Freeman, D. Carl; McArthur, E.D.; Kim, Y.-O.; Redman, R.S.

    2009-01-01

    The growth and development of rice (Oryzae sativa) seedlings was shown to be regulated epigenetically by a fungal endophyte. In contrast to un-inoculated (nonsymbiotic) plants, endophyte colonized (symbiotic) plants preferentially allocated resources into root growth until root hairs were well established. During that time symbiotic roots expanded at five times the rate observed in nonsymbiotic plants. Endophytes also influenced sexual reproduction of mature big sagebrush (Artemisia tridentata) plants. Two spatially distinct big sagebrush subspecies and their hybrids were symbiotic with unique fungal endophytes, despite being separated by only 380 m distance and 60 m elevation. A double reciprocal transplant experiment of parental and hybrid plants, and soils across the hybrid zone showed that fungal endophytes interact with the soils and different plant genotypes to confer enhanced plant reproduction in soil native to the endophyte and reduced reproduction in soil alien to the endophyte. Moreover, the most prevalent endophyte of the hybrid zone reduced the fitness of both parental subspecies. Because these endophytes are passed to the next generation of plants on seed coats, this interaction provides a selective advantage, habitat specificity, and the means of restricting gene flow, thereby making the hybrid zone stable, narrow and potentially leading to speciation. ?? 2009 Landes Bioscience.

  13. 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; ...

  14. Plant nitrogen dynamics and nitrogen-use strategies under altered nitrogen seasonality and competition.

    Science.gov (United States)

    Yuan, Zhiyou; Liu, Weixing; Niu, Shuli; Wan, Shiqiang

    2007-10-01

    Numerous studies have examined the effects of climatic factors on the distribution of C(3) and C(4) grasses in various regions throughout the world, but the role of seasonal fluctuations in temperature, precipitation and soil N availability in regulating growth and competition of these two functional types is still not well understood. This report is about the effects of seasonality of soil N availability and competition on plant N dynamics and N-use strategies of one C(3) (Leymus chinensis) and one C(4) (Chloris virgata) grass species. Leymus chinensis and C. virgata, two grass species native to the temperate steppe in northern China, were planted in a monoculture and a mixture under three different N seasonal availabilities: an average model (AM) with N evenly distributed over the growing season; a one-peak model (OM) with more N in summer than in spring and autumn; and a two-peak model (TM) with more N in spring and autumn than in summer. The results showed that the altered N seasonality changed plant N concentration, with the highest value of L. chinensis under the OM treatment and C. virgata under the TM treatment, respectively. N seasonality also affected plant N content, N productivity and N-resorption efficiency and proficiency in both the C(3) and C(4) species. Interspecific competition influenced N-use and resorption efficiency in both the C(3) and C(4) species, with higher N-use and resorption efficiency in the mixture than in monoculture. The C(4) grass had higher N-use efficiency than the C(3) grass due to its higher N productivity, irrespective of the N treatment or competition. The observations suggest that N-use strategies in the C(3) and C(4) species used in the study were closely related to seasonal dynamics of N supply and competition. N seasonality might be involved in the growth and temporal niche separation between C(3) and C(4) species observed in the natural ecosystems.

  15. Experiments on Growth and Variation of Spaceship Loaded Plant Seeds

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-08-15

    This educational experiment was designed (1)to obtain the basic information on the effects of the space environments on plant growth and mutagenesis, (2)to evaluate plant germination and seedling growth under the effect of microgravity and light conditions and (3)to improve a child's scientific mind through the real-time observations of a seedling growth for two plants conducted both in space and on earth. This project was implemented?as one of the missions in the Korean Astronaut Program. Seeds of eleven plant species (rice, soybean, rape, radish, hot pepper, perilla, arabidopsis, orchids, dandelion, hibiscus, cosmos) was vacuum-sealed in aluminium bags. Those seeds was loaded in the 'Progress' spaceship in Feb. 2008, traveled in the 'Progress', placed in the Russian Sector-International Space Station (RS-ISS), and then was brought by the Korean astronaut from the RS-ISS, and handed over to us at Korea Atomic Energy Research Institute(KAERI). The germination rate, plant growth and mutation type/frequency of the returned plants are under testing in the lab and field in KAERI now. The first Korean astronaut, Dr. So-Yeon Yi, who had returned to earth on April 19, 2008 after successfully completing her scientific mission for 12 days in Space, performed the experiment of plant germination and seedling growth in the International Space Station (ISS), and a similarly designed experiment kit was distributed to conduct the experiment by student and adult volunteers in Korea at the same time. The experiment was to observe the effects of microgravity and light on a seedling growth for soybean and radish. We designed a growth kit that was an all-in-one package consisting of seeds (12 seeds in each chamber) and rock wool as a growing medium filled in four polycarbonate growing chambers in a light proof textile bag or carton paper. The bottom of the chamber was filled with a tightly-fitted rock wool which can hold water and provide moisture during a

  16. Experiments on Growth and Variation of Spaceship Loaded Plant Seeds

    International Nuclear Information System (INIS)

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

    2008-08-01

    This educational experiment was designed (1)to obtain the basic information on the effects of the space environments on plant growth and mutagenesis, (2)to evaluate plant germination and seedling growth under the effect of microgravity and light conditions and (3)to improve a child's scientific mind through the real-time observations of a seedling growth for two plants conducted both in space and on earth. This project was implemented?as one of the missions in the Korean Astronaut Program. Seeds of eleven plant species (rice, soybean, rape, radish, hot pepper, perilla, arabidopsis, orchids, dandelion, hibiscus, cosmos) was vacuum-sealed in aluminium bags. Those seeds was loaded in the 'Progress' spaceship in Feb. 2008, traveled in the 'Progress', placed in the Russian Sector-International Space Station (RS-ISS), and then was brought by the Korean astronaut from the RS-ISS, and handed over to us at Korea Atomic Energy Research Institute(KAERI). The germination rate, plant growth and mutation type/frequency of the returned plants are under testing in the lab and field in KAERI now. The first Korean astronaut, Dr. So-Yeon Yi, who had returned to earth on April 19, 2008 after successfully completing her scientific mission for 12 days in Space, performed the experiment of plant germination and seedling growth in the International Space Station (ISS), and a similarly designed experiment kit was distributed to conduct the experiment by student and adult volunteers in Korea at the same time. The experiment was to observe the effects of microgravity and light on a seedling growth for soybean and radish. We designed a growth kit that was an all-in-one package consisting of seeds (12 seeds in each chamber) and rock wool as a growing medium filled in four polycarbonate growing chambers in a light proof textile bag or carton paper. The bottom of the chamber was filled with a tightly-fitted rock wool which can hold water and provide moisture during a seedling growth. The

  17. Effective Teaching Strategies for Predicting Reading Growth in English Language Learners

    Science.gov (United States)

    Melgarejo, Melina

    2017-01-01

    The goal of the present study was to examine how effective use of teaching strategies predict reading growth among a sample of English Language Learners. The study specifically examined whether the types of teaching strategies that predict growth in decoding skills also predict growth in comprehension skills. The sample consisted of students in…

  18. Trickle water and feeding system in plant culture and light-dark cycle effects on plant growth

    Science.gov (United States)

    Takano, T.; Inada, K.; Takanashi, J.

    1987-01-01

    Rockwool, as an inert medium covered or bagged with polyethylene film, can be effectively used for plant culture in space stations. The most important machine is the pump adjusting the dripping rate in the feeding system. Hydro-aeroponics may be adaptable to a space laboratory. The shortening of the light-dark cycles inhibits plant growth and induces an abnormal morphogenesis. A photoperiod of 12 hr dark may be needed for plant growth.

  19. Colonization of Plant Growth Promoting Rhizobacteria (PGPR) on Two Different Root Systems

    International Nuclear Information System (INIS)

    Chaudhry, M. Z.; Naz, A. U.; Nawaz, A.; Nawaz, A.; Mukhtar, H.

    2016-01-01

    Phytohormones producing bacteria enhance the plants growth by positively affecting growth of the root. Plant growth promoting bacteria (PGPR) must colonize the plant roots to contribute to the plant's endogenous pool of phytohormones. Colonization of these plant growth promoting rhizobacteria isolated from rhizosplane and soil of different crops was evaluated on different root types to establish if the mechanism of host specificity exist. The bacteria were isolated from maize, wheat, rice, canola and cotton and phytohormone production was detected and quantified by HPLC. Bacteria were inoculated on surface sterilized seeds of different crops and seeds were germinated. After 7 days the bacteria were re-isolated from the roots and the effect of these bacteria was observed by measuring increase in root length. Bacteria isolated from one plant family (monocots) having fibrous root performed well on similar root system and failed to give significant results on other roots (tap root) of dicots. Some aggressive strains were able to colonize both root systems. The plant growth promoting activities of the bacteria were optimum on the same plant from whom roots they were isolated. The results suggest that bacteria adapt to the root they naturally inhabit and colonize the same plant root systems preferably. Although the observe trend indicate host specificity but some bacteria were aggressive colonizers which grew on all the plants used in experiment. (author)

  20. Nutrient leaching when soil is part of plant growth media

    Science.gov (United States)

    Soils can serve as sorbents for phosphorus (P) within plant growth media, negating the need for artificial sorbents. The purpose of this study was to compare soils with different properties, as part of plant growth media, for their effect on nutrient levels in effluent. Four soils were mixed with sa...

  1. Influence of integrated phosphorus supply and plant growth ...

    African Journals Online (AJOL)

    To guarantee a sufficient phosphorus supply for plants, a rapid and permanent mobilization of phosphorus from the labile phosphorus fractions is necessary, because phosphorus concentrations in soil solution are generally low. Several plant growth-promoting rhizobacteria (PGPR) have shown potential to enhance ...

  2. Controlled ecological life support systems: Development of a plant growth module

    Science.gov (United States)

    Averner, Mel M.; Macelroy, Robert D.; Smernoff, David T.

    1987-01-01

    An effort was made to begin defining the scientific and technical requirements for the design and construction of a ground-based plant growth facility. In particular, science design criteria for the Plant Growth Module (PGM) of the Controlled Ecological Life Support System (CELSS) were determined in the following areas: (1) irradiation parameters and associated equipment affecting plant growth; (2) air flow; (3) planting, culture, and harvest techniques; (4) carbon dioxide; (5) temperature and relative humidity; (6) oxygen; (7) construction materials and access; (8) volatile compounds; (9) bacteria, sterilization, and filtration; (10) nutrient application systems; (11) nutrient monitoring; and (12) nutrient pH and conductivity.

  3. Invasion strategies in clonal aquatic plants: Are phenotypic differences caused by phenotypic plasticity or local adaptation?

    DEFF Research Database (Denmark)

    Riis, Tenna; Lambertini, Carla; Olesen, Birgit

    2010-01-01

    conditions and plant morphological characteristics. Conclusions: The results indicate that at the current stage of spread into New Zealand, the primary adaptive strategy of these three invasive macrophytes is phenotypic plasticity. However, while limited, the possibility that genetic diversity between......Background and Aims: The successful spread of invasive plants in new environments is often linked to multiple introductions and a diverse gene pool that facilitates local adaptation to variable environmental conditions. For clonal plants, however, phenotypic plasticity may be equally important....... Methods: Field populations with a large phenotypic variety were sampled in a range of lakes and streams with different chemical and physical properties. The phenotypic plasticity of the species before and after cultivation was studied in a common garden growth experiment, and the genetic diversity...

  4. Pectin Methylesterification Impacts the Relationship between Photosynthesis and Plant Growth.

    Science.gov (United States)

    M Weraduwage, Sarathi; Kim, Sang-Jin; Renna, Luciana; C Anozie, Fransisca; D Sharkey, Thomas; Brandizzi, Federica

    2016-06-01

    Photosynthesis occurs in mesophyll cells of specialized organs such as leaves. The rigid cell wall encapsulating photosynthetic cells controls the expansion and distribution of cells within photosynthetic tissues. The relationship between photosynthesis and plant growth is affected by leaf area. However, the underlying genetic mechanisms affecting carbon partitioning to different aspects of leaf growth are not known. To fill this gap, we analyzed Arabidopsis plants with altered levels of pectin methylesterification, which is known to modulate cell wall plasticity and plant growth. Pectin methylesterification levels were varied through manipulation of cotton Golgi-related (CGR) 2 or 3 genes encoding two functionally redundant pectin methyltransferases. Increased levels of methylesterification in a line over-expressing CGR2 (CGR2OX) resulted in highly expanded leaves with enhanced intercellular air spaces; reduced methylesterification in a mutant lacking both CGR-genes 2 and 3 (cgr2/3) resulted in thin but dense leaf mesophyll that limited CO2 diffusion to chloroplasts. Leaf, root, and plant dry weight were enhanced in CGR2OX but decreased in cgr2/3. Differences in growth between wild type and the CGR-mutants can be explained by carbon partitioning but not by variations in area-based photosynthesis. Therefore, photosynthesis drives growth through alterations in carbon partitioning to new leaf area growth and leaf mass per unit leaf area; however, CGR-mediated pectin methylesterification acts as a primary factor in this relationship through modulation of the expansion and positioning of the cells in leaves, which in turn drive carbon partitioning by generating dynamic carbon demands in leaf area growth and leaf mass per unit leaf area. © 2016 American Society of Plant Biologists. All Rights Reserved.

  5. Materials and methods to increase plant growth and yield

    Science.gov (United States)

    Kirst, Matias

    2017-05-16

    The present invention relates to materials and methods for modulating growth rates, yield, and/or resistance to drought conditions in plants. In one embodiment, a method of the invention comprises increasing expression of an hc1 gene (or a homolog thereof that provides for substantially the same activity), or increasing expression or activity of the protein encoded by an hc1 gene thereof, in a plant, wherein expression of the hc1 gene or expression or activity of the protein encoded by an hc1 gene results in increased growth rate, yield, and/or drought resistance in the plant.

  6. Solid-support substrates for plant growth at a lunar base

    Science.gov (United States)

    Ming, D. W.; Galindo, C.; Henninger, D. L.

    1990-01-01

    Zeoponics is only in its developmental stages at the Johnson Space Center and is defined as the cultivation of plants in zeolite substrates that contain several essential plant growth cations on their exchange sites, and have minor amounts of mineral phases and/or anion-exchange resins that supply essential plant growth anions. Zeolites are hydrated aluminosilicates of alkali and alkaline earth cations with the ability to exchange most of their constituent exchange cations as well as hydrate/dehydrate without change to their structural framework. Because zeolites have extremely high cation exchange capabilities, they are very attractive media for plant growth. It is possible to partially or fully saturate plant-essential cations on zeolites. Zeoponic systems will probably have their greatest applications at planetary bases (e.g., lunar bases). Lunar raw materials will have to be located that are suited for the synthesis of zeolites and other exchange resings. Lunar 'soil' simulants have been or are being prepared for zeolite/smectite synthesis and 'soil' dissolution studies.

  7. 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.

  8. 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.

  9. Phosphorus mobilizing consortium Mammoth P™ enhances plant growth

    Science.gov (United States)

    Bell, Colin; Mancini, Lauren M.; Lee, Melanie N.; Conant, Richard T.; Wallenstein, Matthew D.

    2016-01-01

    Phosphorus (P) is a critical nutrient used to maximize plant growth and yield. Current agriculture management practices commonly experience low plant P use efficiency due to natural chemical sorption and transformations when P fertilizer is applied to soils. A perplexing challenge facing agriculture production is finding sustainable solutions to deliver P more efficiently to plants. Using prescribed applications of specific soil microbial assemblages to mobilize soil bound—P to improve crop nutrient uptake and productivity has rarely been employed. We investigated whether inoculation of soils with a bacterial consortium developed to mobilize soil P, named Mammoth PTM, could increase plant productivity. In turf, herbs, and fruits, the combination of conventional inorganic fertilizer combined with Mammoth PTM increased productivity up to twofold compared to the fertilizer treatments without the Mammoth PTM inoculant. Jalapeño plants were found to bloom more rapidly when treated with either Mammoth P. In wheat trials, we found that Mammoth PTM by itself was able to deliver yields equivalent to those achieved with conventional inorganic fertilizer applications and improved productivity more than another biostimulant product. Results from this study indicate the substantial potential of Mammoth PTM to enhance plant growth and crop productivity. PMID:27326379

  10. Impact of planting dates and insecticide strategies for managing crucifer flea beetles (Coleoptera: Chrysomelidae) in spring-planted canola.

    Science.gov (United States)

    Knodel, Janet J; Olson, Denise L; Hanson, Bryan K; Henson, Robert A

    2008-06-01

    Integration of cultural practices, such as planting date with insecticide-based strategies, was investigated to determine best management strategy for flea beetles (Phyllotreta spp.) (Coleoptera: Chrysomelidae) in canola (Brassica napus L.). We studied the effect of two spring planting dates of B. napus and different insecticide-based management strategies on the feeding injury caused by fleabeetles in North Dakota during 2002-2003. Adult beetle peak emergence usually coincided with the emergence of the early planted canola, and this resulted in greater feeding injury in the early planted canola than later planted canola. Use of late-planted canola may have limited potential for cultural control of flea beetle, because late-planted canola is at risk for yield loss due to heat stress during flowering. Flea beetle injury ratings declined when 1) the high rate of insecticide seed treatment plus a foliar insecticide applied 21 d after planting was used, 2) the high rate of insecticide seed treatment only was used, or 3) two foliar insecticide sprays were applied. These insecticide strategies provided better protection than the low rates of insecticide seed treatments or a single foliar spray, especially in areas with moderate-to-high flea beetle populations. The foliar spray on top of the seed treatment controlled later-emerging flea beetles as the seed treatment residual was diminishing and the crop became vulnerable to feeding injury. The best insecticide strategy for management of flea beetle was the high rate of insecticide seed treatment plus a foliar insecticide applied at 21 d after planting, regardless of planting date.

  11. Microbiome Selection Could Spur Next-Generation Plant Breeding Strategies.

    Science.gov (United States)

    Gopal, Murali; Gupta, Alka

    2016-01-01

    " No plant is an island too …" Plants, though sessile, have developed a unique strategy to counter biotic and abiotic stresses by symbiotically co-evolving with microorganisms and tapping into their genome for this purpose. Soil is the bank of microbial diversity from which a plant selectively sources its microbiome to suit its needs. Besides soil, seeds, which carry the genetic blueprint of plants during trans-generational propagation, are home to diverse microbiota that acts as the principal source of microbial inoculum in crop cultivation. Overall, a plant is ensconced both on the outside and inside with a diverse assemblage of microbiota. Together, the plant genome and the genes of the microbiota that the plant harbors in different plant tissues, i.e., the 'plant microbiome,' form the holobiome which is now considered as unit of selection: 'the holobiont.' The 'plant microbiome' not only helps plants to remain fit but also offers critical genetic variability, hitherto, not employed in the breeding strategy by plant breeders, who traditionally have exploited the genetic variability of the host for developing high yielding or disease tolerant or drought resistant varieties. This fresh knowledge of the microbiome, particularly of the rhizosphere, offering genetic variability to plants, opens up new horizons for breeding that could usher in cultivation of next-generation crops depending less on inorganic inputs, resistant to insect pest and diseases and resilient to climatic perturbations. We surmise, from ever increasing evidences, that plants and their microbial symbionts need to be co-propagated as life-long partners in future strategies for plant breeding. In this perspective, we propose bottom-up approach to co-propagate the co-evolved, the plant along with the target microbiome, through - (i) reciprocal soil transplantation method, or (ii) artificial ecosystem selection method of synthetic microbiome inocula, or (iii) by exploration of microRNA transfer

  12. Wound-induced endogenous jasmonates stunt plant growth by inhibiting mitosis.

    Directory of Open Access Journals (Sweden)

    Yi Zhang

    Full Text Available When plants are repeatedly injured their growth is stunted and the size of organs such as leaves is greatly reduced. The basis of this effect is not well-understood however, even though it reduces yield of crops injured by herbivory, and produces dramatic effects exemplified in ornamental bonsai plants. We have investigated the genetic and physiological basis of this "bonsai effect" by repeatedly wounding leaves of the model plant Arabidopsis. This treatment stunted growth by 50% and increased the endogenous content of jasmonate (JA, a growth inhibitor, by seven-fold. Significantly, repeated wounding did not stunt the growth of the leaves of mutants unable to synthesise JA, or unable to respond to JA including coi1, jai3, myc2, but not jar1. The stunted growth did not result from reduced cell size, but resulted instead from reduced cell number, and was associated with reduced expression of CycB1;2. Wounding caused systemic disappearance of constitutively expressed JAZ1::GUS. Wounding also activates plant immunity. We show that a gene, 12-oxo-phytodienoate reductase, which catalyses a step in JA biosynthesis, and which we confirm is not required for defence, is however required for wound-induced stunting. Our data suggest that intermediates in the JA biosynthetic pathway activate defence, but a primary function of wound-induced JA is to stunt growth through the suppression of mitosis.

  13. Wound-induced endogenous jasmonates stunt plant growth by inhibiting mitosis.

    Science.gov (United States)

    Zhang, Yi; Turner, John G

    2008-01-01

    When plants are repeatedly injured their growth is stunted and the size of organs such as leaves is greatly reduced. The basis of this effect is not well-understood however, even though it reduces yield of crops injured by herbivory, and produces dramatic effects exemplified in ornamental bonsai plants. We have investigated the genetic and physiological basis of this "bonsai effect" by repeatedly wounding leaves of the model plant Arabidopsis. This treatment stunted growth by 50% and increased the endogenous content of jasmonate (JA), a growth inhibitor, by seven-fold. Significantly, repeated wounding did not stunt the growth of the leaves of mutants unable to synthesise JA, or unable to respond to JA including coi1, jai3, myc2, but not jar1. The stunted growth did not result from reduced cell size, but resulted instead from reduced cell number, and was associated with reduced expression of CycB1;2. Wounding caused systemic disappearance of constitutively expressed JAZ1::GUS. Wounding also activates plant immunity. We show that a gene, 12-oxo-phytodienoate reductase, which catalyses a step in JA biosynthesis, and which we confirm is not required for defence, is however required for wound-induced stunting. Our data suggest that intermediates in the JA biosynthetic pathway activate defence, but a primary function of wound-induced JA is to stunt growth through the suppression of mitosis.

  14. Catch the Best: Novel Screening Strategy to Select Stress Protecting Agents for Crop Plants

    Directory of Open Access Journals (Sweden)

    Christin Zachow

    2013-11-01

    Full Text Available Climate change increases stress levels for crops and affects the economic and environmental aspects of agricultural management systems. The application of stress tolerance-mediating microorganisms is an auspicious strategy for improving crop protection, and as such, we developed a direct selection strategy to obtain cultivable microorganisms from promising bioresources using the bait plants, maize, oilseed rape, sorghum and sugar beet. Alpine mosses, lichens and primrose were selected as bioresources, as each is adapted to adverse environmental conditions. A 10% crop-specific selection was found for bait plant rhizosphere communities using cultivation-independent fingerprints, and their potential role as stress protecting agents (SPA was evaluated following the cultivation of captured bacteria. In addition to assays identifying phytopathogen antagonism and plant growth promotion capacities, our evaluation included those that test the ability to allocate nutrients. Moreover, we developed new assays to measure tolerance in diverse stress conditions. A score scheme was applied to select SPAs with desired properties, and three Pseudomonas species with pronounced antagonistic activity that showed elevated tolerance to desiccation and an improved seed germination rate were subsequently chosen. Screening for environmentally-conditioned and host-adapted microorganisms provides a novel tool for target-oriented exploitation of microbial bioresources for the management of ecofriendly crops facing biotic and abiotic stresses.

  15. Plant growth promoting potential of endophytic bacteria isolated ...

    African Journals Online (AJOL)

    Endophytic microorganisms are able to promote plant growth through various mechanisms, such as production of plant hormones and antimicrobial substances, as well as to provide the soil with nutrients, for instance, inorganic phosphate. This study aimed to evaluate the potential of endophytic bacteria isolated from ...

  16. Stripping Away the Soil : Plant Growth Promoting Microbiology Opportunities in Aquaponics

    NARCIS (Netherlands)

    Bartelme, Ryan P; Oyserman, Ben O; Blom, Jesse E; Sepulveda-Villet, Osvaldo J; Newton, Ryan J

    2018-01-01

    As the processes facilitated by plant growth promoting microorganisms (PGPMs) become better characterized, it is evident that PGPMs may be critical for successful sustainable agricultural practices. Microbes enrich plant growth through various mechanisms, such as enhancing resistance to disease and

  17. Effects of air pollution on plant growth

    Energy Technology Data Exchange (ETDEWEB)

    Bleasadle, J K.A.

    1959-01-01

    The environment for plant growth is affected in three ways by the presence of coal smoke (1) by a reduction in the amount of light available to the plants, (2) by an alteration in soil conditions, and (3) by the contamination of the air by foreign gases. The smoke haze in or near industrial areas reduced the light available to plants for photosynthesis, thus reducing their growth rate. The tarry deposit on leaves further reduced the light available to the plant, and lowered the assimilation rate. It was generally thought that rain falling in or near industrial areas dissolved the predominantly acidic polluting gases from the air and leached bases from the soil. Rainwater collected showed a reduced number of soil bacteria, resulting in a reduction in the availability of plant nutrients. The most common and abundant gaseous pollutant in Britain was sulfur dioxide formed from the sulfur contained in coal. Concentrations of 0.5 parts per million induced symptoms of leaf scorch in many species. Results showed the yield of Aberystwyth 523 ryegrass was reduced when plants were grown continuously in air polluted with coal smoke. This affected the processes involving cell division. Coal smoke and sulfur also increased the rate of leaf senescence. This rate increased as the concentration of sulfur dioxide increased, or as the length of exposure per day to a standard concentration was increased. The leaves of evergreen trees and shrubs also aged more rapidly in conditions of pollution. 14 references.

  18. Isolation and identification of plant growth promoting rhizobacteria from maize (Zea mays L. rhizosphere and their plant growth promoting effect on rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Karnwal Arun

    2017-06-01

    Full Text Available The use of plant growth promoting rhizobacteria is increasing in agriculture and gives an appealing manner to replace chemical fertilizers, pesticides, and dietary supplements. The objective of our research was to access the plant growth promotion traits of Pseudomonas aeruginosa, P. fluorescens and Bacillus subtilis isolated from the maize (Zea mays L. rhizosphere. In vitro studies showed that isolates have the potential to produce indole acetic acid (IAA, hydrogen cyanide, phosphate solubilisation, and siderophore. RNA analysis revealed that two isolates were 97% identical to P. aeruginosa strain DSM 50071 and P. aeruginosa strain NBRC 12689 (AK20 and AK31, while two others were 98% identical to P. fluorescens strain ATCC 13525, P. fluorescens strain IAM 12022 (AK18 and AK45 and one other was 99% identical to B. subtilis strain NCDO 1769 (AK38. Our gnotobiotic study showed significant differences in plant growth variables under control and inoculated conditions. In the present research, it was observed that the isolated strains had good plant growth promoting effects on rice.

  19. deaminase from plant growth promoting rhizobacteria in Striga

    African Journals Online (AJOL)

    Experiments were conducted in pots to determine the growth effect of different rhizobacteria on maize under Striga hermonthica infestation. Three bacteria were selected based on their plant growth promoting effects. Whole bacterial cells of the rhizobacteria were used to amplify 1-amino-cyclopropane-1-carboxylic acid ...

  20. Chemical diversity of microbial volatiles and their potential for plant growth and productivity

    Directory of Open Access Journals (Sweden)

    CHIDANANDA NAGAMANGALA KANCHISWAMY

    2015-03-01

    Full Text Available Microbial volatile organic compounds (MVOCs are produced by a wide array of microorganisms ranging from bacteria to fungi. A growing body of evidence indicates that MVOCs are ecofriendly and can be exploited as a cost-effective sustainable strategy for use in agricultural practice as agents that enhance plant growth, productivity and disease resistance. As naturally occurring chemicals, MVOCs have potential as possible alternatives to harmful pesticides, fungicides and bactericides as well as genetic modification. Recent studies performed under open field conditions demonstrate that efficiently adopting MVOCs may contribute to sustainable crop protection and production. We review here the chemical diversity of MVOCs and their potential physiological effects on crops and analyze potential and actual limitations for MVOC use as a sustainable strategy for improving productivity and reducing pesticide use.

  1. Plant growth promoters and methods of using them

    KAUST Repository

    Al-Babili, Salim

    2017-01-05

    New plant growth regulators, including compounds and compositions, and methods of use including for promoting root growth. The compounds are carotenoid oxidation products, and a preferred example is 3-OH--β-apo-13-Carotenone. A method comprising promoting the growth of at least one plant with use of an effective amount of at least one composition comprising an effective amount of at least one compound which is represented by A-B-C, wherein B is a bivalent polyene moiety, A is a monovalent moiety linked to B by a six-membered carbon ring, wherein the ring has at least one substituent linked to the ring by an oxygen atom, and C is a monovalent moiety linked to B by a carbonyl group. Synergistic effects can be used with combinations of compounds.

  2. Plant growth and laboratory atmosphere. [Phaseolus multiflorus Willd

    Energy Technology Data Exchange (ETDEWEB)

    Richter, O

    1903-01-01

    The author observed that Phaseolus seedlings grown under glass bell jars which were closed off by water were two or three times as long as those seedlings which were grown under jars without the water closure. It was suspected that coal gas or other impurities were causing these results. Thus, experiments were performed to determine if indeed coal gas was affecting plant growth. Results indicated that coal gas has an inhibiting effect on the growth and length of the seedlings, but it also promotes the growth in thickness. Shortening and thickening was proportional to the concentration of the coal gas and the time of exposure. Mercury vapors were found to produce similar differences in height and thickness of seedlings as coal gas, but they are at the same time lethal to the plants.

  3. of Effect of different organic materials on plant growth

    Directory of Open Access Journals (Sweden)

    mehrnosh eskandari

    2009-06-01

    Full Text Available Using organic matter, such as, peat and vermicompost as soil amendment, increases aeration, water infiltration, water holding capacity and nutrients of soil . A greenhouse experiment was performed to study the effect of organic materials on plant growth characteristics, total biomass and grain weight of chickpea with four treatments; 1 Soil + 3% peat (PS, 2 Sterile soil + 3% peat (SPS, 3 Soil + vermicompost (1:6 (VCS, 4 control (C in a completely randomized design with four replications. The results showed that the maximum germination percentage, number of branch and number of pod per plant were observed in SPS treatment due to the avoidance of harmful microbial impacts. Plant height in this treatment reduced, whereas, no significant differences in total dry matter per plant and dry weight of chickpea per plant were observed compared to control. Plant growth consist of plant height, number of branch and number of pod per plant in vermicompost and soil + peat treatment reduced in the early stages probably because of plant - microbes interaction effects. Application of vermicompost increased fresh and dry weight, pod dry weight and single grain weight, probably due to more plant nutrient availability in this treatment when compared with other treatments.

  4. Effect of plant growth regulators on callus induction and plant ...

    African Journals Online (AJOL)

    The present study was conducted to investigate the effects of different concentrations and combinations of growth regulators on callus induction and plant regeneration of potato (Solanum tuberosum L.) cultivar Diamant. The tuber segments were used as explants and cultured on Murashige and Skoog (MS) medium ...

  5. Assessing the suitability of paste as a medium for plant growth

    International Nuclear Information System (INIS)

    Feng Yongsheng; Sinclair, L.; Fung, Y.P.

    1999-01-01

    When a polymer is added to the tailings slurry in the extraction process in oil sands refining, it accelerates the release of water and forms a consolidated, dense material known as 'paste.' This material has a solids content of approximately 65% by weight, 30% of which is made up of fine particles. A study was initiated to explore the possibility of using paste as a plant growth medium in which the paste must hold water and nutrients for growth while allowing adequate water movement and aeration. To also attain a favorable soil structure, it was thought that amending the paste with an adequate amount of peat would improve its physical and chemical properties such as to render it a suitable soil environment for plant growth. The study was a growth chamber experiment in which the effects were assessed of peat amendments on seed germination, and a greenhouse experiment in which the growth of three selected plant species were determined, including highlander grass, jack pine, and trembling aspen. Paste has the potential to be modified into a suitable plant growth medium. Adding peat can greatly enhance seed germination, and seedling survival and growth. There seemed to be some improvement in plant performance as the amount of peat included increased from 5% to 10%. Increasing the amount of peat still further to 15% had at best marginal incremental effects. The optimum amount of peat amendment was around 10%. Of the three plant types tested, highlander grass performed the best on the paste material amended with peat, showing performance comparable to the control. Trembling aspen grew relatively well but the survival rate was low. If the seedlings survived the first few weeks, the potential for continued growth seemed good. Jack pine showed signs of stress such as needle damage, stunted growth and low survival rates and seemed unlikely to establish well even on the peat amended paste. 1 ref., 4 tabs., 2 figs

  6. Laboratory study on influence of plant growth promoting ...

    African Journals Online (AJOL)

    The influence of rhizobacteria on the growth and tolerance of Zea mays (maize) in a petroleum hydrocarbon (crude oil) impacted medium was investigated. This study evaluated the effect of inoculating maize seeds with plant growth promoting rhizobacterial strains in a crude oil impacted medium. The rhizobacterial strains ...

  7. Preferential Promotion of Lycopersicon esculentum (Tomato) Growth by Plant Growth Promoting Bacteria Associated with Tomato.

    Science.gov (United States)

    Vaikuntapu, Papa Rao; Dutta, Swarnalee; Samudrala, Ram Babu; Rao, Vukanti R V N; Kalam, Sadaf; Podile, Appa Rao

    2014-12-01

    A total of 74 morphologically distinct bacterial colonies were selected during isolation of bacteria from different parts of tomato plant (rhizoplane, phylloplane and rhizosphere) as well as nearby bulk soil. The isolates were screened for plant growth promoting (PGP) traits such as production of indole acetic acid, siderophore, chitinase and hydrogen cyanide as well as phosphate solubilization. Seven isolates viz., NR4, NR6, RP3, PP1, RS4, RP6 and NR1 that exhibited multiple PGP traits were identified, based on morphological, biochemical and 16S rRNA gene sequence analysis, as species that belonged to four genera Aeromonas, Pseudomonas, Bacillus and Enterobacter. All the seven isolates were positive for 1-aminocyclopropane-1-carboxylate deaminase. Isolate NR6 was antagonistic to Fusarium solani and Fusarium moniliforme, and both PP1 and RP6 isolates were antagonistic to F. moniliforme. Except RP6, all isolates adhered significantly to glass surface suggestive of biofilm formation. Seed bacterization of tomato, groundnut, sorghum and chickpea with the seven bacterial isolates resulted in varied growth response in laboratory assay on half strength Murashige and Skoog medium. Most of the tomato isolates positively influenced tomato growth. The growth response was either neutral or negative with groundnut, sorghum and chickpea. Overall, the results suggested that bacteria with PGP traits do not positively influence the growth of all plants, and certain PGP bacteria may exhibit host-specificity. Among the isolates that positively influenced growth of tomato (NR1, RP3, PP1, RS4 and RP6) only RS4 was isolated from tomato rhizosphere. Therefore, the best PGP bacteria can also be isolated from zones other than rhizosphere or rhizoplane of a plant.

  8. Preliminary results of Physiological plant growth modelling for human life support in space

    Science.gov (United States)

    Sasidharan L, Swathy; Dussap, Claude-Gilles; Hezard, Pauline

    2012-07-01

    Human life support is fundamental and crucial in any kind of space explorations. MELiSSA project of European Space Agency aims at developing a closed, artificial ecological life support system involving human, plants and micro organisms. Consuming carbon dioxide and water from the life support system, plants grow in one of the chambers and convert it into food and oxygen along with potable water. The environmental conditions, nutrient availability and its consumption of plants should be studied and necessarily modeled to predict the amount of food, oxygen and water with respect to the environmental changes and limitations. The reliability of a completely closed system mainly depends on the control laws and strategies used. An efficient control can occur, only if the system to control is itself well known, described and ideally if the responses of the system to environmental changes are predictable. In this aspect, the general structure of plant growth model has been designed together with physiological modelling.The physiological model consists of metabolic models of leaves, stem and roots, of which concern specific metabolisms of the associated plant parts. On the basis of the carbon source transport (eg. sucrose) through stem, the metabolic models (leaf and root) can be interconnected to each other and finally coupled to obtain the entire plant model. For the first step, leaf metabolic model network was built using stoichiometric, mass and energy balanced metabolic equations under steady state approach considering all necessary plant pathways for growth and maintenance of leaves. As the experimental data for lettuce plants grown in closed and controlled environmental chambers were available, the leaf metabolic model has been established for lettuce leaves. The constructed metabolic network is analyzed using known stoichiometric metabolic technique called metabolic flux analysis (MFA). Though, the leaf metabolic model alone is not sufficient to achieve the

  9. Relationship termination in emerging adulthood: Coping strategies as predictors of posttraumatic growth

    Directory of Open Access Journals (Sweden)

    Simona Zgaga

    2013-02-01

    Full Text Available Relationship termination happens relatively often in emerging adulthood but is nevertheless as distressing then as it is later in life. We examined the relationship between coping strategies and posttraumatic growth in a sample of 260 emerging adults whose heterosexual romantic relationships were terminated at most two years before participating in the study. Participants completed The Posttraumatic Growth Inventory, The COPE Inventory and Emotion Approach Coping scale. For the purposes of the study we also conceptualized a new coping inventory, related specifically to coping with relationship termination. While controlling for gender and age the coping strategies explained 34 % of variability in posttraumatic growth. Statistically significant predictors of posttraumatic growth were problem-oriented coping strategies, coping strategies, oriented towards emotions and other people, acceptance and positive self-motivation as well as coping strategies that allow some distancing from the stressor. Results indicate that posttraumatic growth is related to problem-oriented and also to emotion-oriented coping strategies, which is reasonable since relationship termination is a stressor that cannot be eliminated. It is important that an individual who is facing it can cope well with the unpleasant emotions deriving from relationship termination.

  10. Demonstrating the Effects of Light Quality on Plant Growth.

    Science.gov (United States)

    Whitesell, J. H.; Garcia, Maria

    1977-01-01

    Describes a lab demonstration that illustrates the effect of different colors or wavelengths of visible light on plant growth and development. This demonstration is appropriate for use in college biology, botany, or plant physiology courses. (HM)

  11. Stripping Away the Soil: Plant Growth Promoting Microbiology Opportunities in Aquaponics

    OpenAIRE

    Bartelme, Ryan P; Oyserman, Ben O; Blom, Jesse E; Sepulveda-Villet, Osvaldo J; Newton, Ryan J

    2018-01-01

    As the processes facilitated by plant growth promoting microorganisms (PGPMs) become better characterized, it is evident that PGPMs may be critical for successful sustainable agricultural practices. Microbes enrich plant growth through various mechanisms, such as enhancing resistance to disease and drought, producing beneficial molecules, and supplying nutrients and trace metals to the plant rhizosphere. Previous studies of PGPMs have focused primarily on soil-based crops. In contrast, aquapo...

  12. Shifts in growth strategies reflect tradeoffs in cellular economics

    Science.gov (United States)

    Molenaar, Douwe; van Berlo, Rogier; de Ridder, Dick; Teusink, Bas

    2009-01-01

    The growth rate-dependent regulation of cell size, ribosomal content, and metabolic efficiency follows a common pattern in unicellular organisms: with increasing growth rates, cell size and ribosomal content increase and a shift to energetically inefficient metabolism takes place. The latter two phenomena are also observed in fast growing tumour cells and cell lines. These patterns suggest a fundamental principle of design. In biology such designs can often be understood as the result of the optimization of fitness. Here we show that in basic models of self-replicating systems these patterns are the consequence of maximizing the growth rate. Whereas most models of cellular growth consider a part of physiology, for instance only metabolism, the approach presented here integrates several subsystems to a complete self-replicating system. Such models can yield fundamentally different optimal strategies. In particular, it is shown how the shift in metabolic efficiency originates from a tradeoff between investments in enzyme synthesis and metabolic yields for alternative catabolic pathways. The models elucidate how the optimization of growth by natural selection shapes growth strategies. PMID:19888218

  13. 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 ...

  14. Nutrient foraging strategies are associated with productivity and population growth in forest shrubs

    Science.gov (United States)

    Stone, Bram W. G.; Faillace, Cara A.; Lafond, Jonathan J.; Baumgarten, Joni M.; Mozdzer, Thomas J.; Dighton, John; Meiners, Scott J.; Grabosky, Jason C.; Ehrenfeld, Joan G.

    2017-01-01

    Background and Aims Temperate deciduous forest understoreys are experiencing widespread changes in community composition, concurrent with increases in rates of nitrogen supply. These shifts in plant abundance may be driven by interspecific differences in nutrient foraging (i.e. conservative vs. acquisitive strategies) and, thus, adaptation to contemporary nutrient loading conditions. This study sought to determine if interspecific differences in nutrient foraging could help explain patterns of shrub success and decline in eastern North American forests. Methods Using plants grown in a common garden, fine root traits associated with nutrient foraging were measured for six shrub species. Traits included the mean and skewness of the root diameter distribution, specific root length (SRL), C:N ratio, root tissue density, arbuscular mycorrhizal colonization and foraging precision. Above- and below-ground productivity were also determined for the same plants, and population growth rates were estimated using data from a long-term study of community dynamics. Root traits were compared among species and associations among root traits, measures of productivity and rates of population growth were evaluated. Key Results Species fell into groups having thick or thin root forms, which correspond to conservative vs. acquisitive nutrient foraging strategies. Interspecific variation in root morphology and tissue construction correlated with measures of productivity and rates of cover expansion. Of the four species with acquisitive traits, three were introduced species that have become invasive in recent decades, and the fourth was a weedy native. In contrast, the two species with conservative traits were historically dominant shrubs that have declined in abundance in eastern North American forests. Conclusions In forest understoreys of eastern North America, elevated nutrient availability may impose a filter on species success in addition to above-ground processes such as herbivory

  15. Effect of Media Culture on Growth and Sucker Pandanus Plant

    Directory of Open Access Journals (Sweden)

    ali salehi sardoei

    2017-02-01

    Full Text Available Introduction: One factor that is of great importance to the cultivation of flowers and ornamental plants, is the media. Planting plants in containers as an important component of the nursery technology has grown. Compared with farm volume, growth media used for each plant greatly reduce plant growth that largely influence by the physical and chemical properties of growth media used. Therefore, good management of potted plants bed will cause the plants have good quality. A good growth media with optimal physical and biological properties, relatively inexpensive, stable and style enough to work should be available. The Burgers showed that composted green waste can be used as substrates for soilless cultivation and improve the water-holding capacity of soil. The garden has a range of materials including hardwood and softwood bark, leaves, soil, waste, sewage sludge and coconut (cocopeat that has been used as a seed bed. According to the economic issues and increasing moisture storage, palm peat substrates are primary material that can be prepared as a good growth medium for the producing's presented level Country. Peat moss is not applicable to all plants because of high cost and poor absorption characteristics like low pH and low water holding capacity . This study was conducted to investigate the possibility of replacing peat moss palm waste and the effect of it on growth characteristics were studied. Materials and Methods: The experimental design was completely randomized design with four replications of eight treatments. The compressed unit (block was supplied and commercial cocopeat was used because of reducing the cost of transportation. Before applying this material, the amount of water was added for opening up and voluminous and become it completely uniform.. In treatments containing sand + perlite, these four types volume ratio of 1:1 and mixed with sand + perlite were used. First, wooden cuttings of pandanus in a bed of sand rooted in the

  16. Agriculture on Mars: Soils for Plant Growth

    Science.gov (United States)

    Ming, D. W.

    2016-01-01

    Robotic rovers and landers have enabled the mineralogical, chemical, and physical characterization of loose, unconsolidated materials on the surface of Mars. Planetary scientists refer to the regolith material as "soil." NASA is currently planning to send humans to Mars in the mid 2030s. Early missions may rely on the use of onsite resources to enable exploration and self-sufficient outposts on Mars. The martian "soil" and surface environment contain all essential plant growth elements. The study of martian surface materials and how they might react as agricultural soils opens a new frontier for researchers in the soil science community. Other potential applications for surface "soils" include (i) sources for extraction of essential plant-growth nutrients, (ii) sources of O2, H2, CO2, and H2O, (iii) substrates for microbial populations in the degradation of wastes, and (iv) shielding materials surrounding outpost structures to protect humans, plants, and microorganisms from radiation. There are many challenges that will have to be addressed by soil scientists prior to human exploration over the next two decades.

  17. Effects of Engineered Nanomaterials on Plants Growth: An Overview

    Science.gov (United States)

    Bagheri, Samira; Muhd Julkapli, Nurhidayatullaili; Juraimi, Abdul Shukor; Hashemi, Farahnaz Sadat Golestan

    2014-01-01

    Rapid development and wide applications of nanotechnology brought about a significant increment on the number of engineered nanomaterials (ENs) inevitably entering our living system. Plants comprise of a very important living component of the terrestrial ecosystem. Studies on the influence of engineered nanomaterials (carbon and metal/metal oxides based) on plant growth indicated that in the excess content, engineered nanomaterials influences seed germination. It assessed the shoot-to-root ratio and the growth of the seedlings. From the toxicological studies to date, certain types of engineered nanomaterials can be toxic once they are not bound to a substrate or if they are freely circulating in living systems. It is assumed that the different types of engineered nanomaterials affect the different routes, behavior, and the capability of the plants. Furthermore, different, or even opposing conclusions, have been drawn from most studies on the interactions between engineered nanomaterials with plants. Therefore, this paper comprehensively reviews the studies on the different types of engineered nanomaterials and their interactions with different plant species, including the phytotoxicity, uptakes, and translocation of engineered nanomaterials by the plant at the whole plant and cellular level. PMID:25202734

  18. Information Integration and Communication in Plant Growth Regulation.

    Science.gov (United States)

    Chaiwanon, Juthamas; Wang, Wenfei; Zhu, Jia-Ying; Oh, Eunkyoo; Wang, Zhi-Yong

    2016-03-10

    Plants are equipped with the capacity to respond to a large number of diverse signals, both internal ones and those emanating from the environment, that are critical to their survival and adaption as sessile organisms. These signals need to be integrated through highly structured intracellular networks to ensure coherent cellular responses, and in addition, spatiotemporal actions of hormones and peptides both orchestrate local cell differentiation and coordinate growth and physiology over long distances. Further, signal interactions and signaling outputs vary significantly with developmental context. This review discusses our current understanding of the integrated intracellular and intercellular signaling networks that control plant growth. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Phenological growth stages of saffron plant (Crocus sativus L.) according to the BBCH Scale

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Corcoles, H.; Brasa-Ramos, A.; Montero-Garcia, F.; Romero-Valverde, M.; Montero-Riquelme, F.

    2015-07-01

    Phenological studies are important for understanding the influence of climate dynamics on vegetative growth, flowering and fruiting on plants and can be used in many scientific subjects, such as Agronomy, Botany and Plant Biology, but also Climatology as a result of the current global interest in climate change monitoring. The purpose of the detailed specific culture descriptions of the principal growth stages in plants is to provide an instrument for standardization of data recording. To date, there was no coding method to describe developmental stages on saffron plant (Crocus sativus L.). Because of the increasing world-wide interest on this crop, a novel growth development code based on the BBCH extended scale is proposed in this paper. Six principal growth stages were set up, starting from sprouting, cataphylls and flowers appearance, plant appearance and development, replacement corms development, plant senescence and corm dormancy. Each principal growth stage is subdivided into secondary growth stages. Descriptive keys with illustrations are included to make effective use of the system. (Author)

  20. Degradation of PVC/HC blends. II. Terrestrial plant growth test.

    Science.gov (United States)

    Pascu, Mihaela; Agafiţei, Gabriela-Elena; Profire, Lenuţa; Vasile, Cornelia

    2009-01-01

    The behavior at degradation by soil burial of some plasticized polyvinyl chloride (PVC) based blends with a variable content of hydrolyzed collagen (HC) has been followed. The modifications induced in the environment by the polymer systems (pH variation, physiologic state of the plants, assimilatory pigments) were studied. Using the growth test of the terrestrial plants, we followed the development of Triticum (wheat), Helianthus annus minimus (little sunflower), Pisum sativum (pea), and Vicia X hybrida hort, during a vegetation cycle. After the harvest, for each plant, the quantities of chlorophyll and carotenoidic pigments and of trace- and macroelements were determined. It was proved that, in the presence of polymer blends, the plants do not suffer morphological and physiological modifications, the products released in the culture soil being not toxic for the plants growth.

  1. Exploration of plant growth and development using the European Modular Cultivation System facility on the International Space Station.

    Science.gov (United States)

    Kittang, A-I; Iversen, T-H; Fossum, K R; Mazars, C; Carnero-Diaz, E; Boucheron-Dubuisson, E; Le Disquet, I; Legué, V; Herranz, R; Pereda-Loth, V; Medina, F J

    2014-05-01

    Space experiments provide a unique opportunity to advance our knowledge of how plants respond to the space environment, and specifically to the absence of gravity. The European Modular Cultivation System (EMCS) has been designed as a dedicated facility to improve and standardise plant growth in the International Space Station (ISS). The EMCS is equipped with two centrifuges to perform experiments in microgravity and with variable gravity levels up to 2.0 g. Seven experiments have been performed since the EMCS was operational on the ISS. The objectives of these experiments aimed to elucidate phototropic responses (experiments TROPI-1 and -2), root gravitropic sensing (GRAVI-1), circumnutation (MULTIGEN-1), cell wall dynamics and gravity resistance (Cell wall/Resist wall), proteomic identification of signalling players (GENARA-A) and mechanism of InsP3 signalling (Plant signalling). The role of light in cell proliferation and plant development in the absence of gravity is being analysed in an on-going experiment (Seedling growth). Based on the lessons learned from the acquired experience, three preselected ISS experiments have been merged and implemented as a single project (Plant development) to study early phases of seedling development. A Topical Team initiated by European Space Agency (ESA), involving experienced scientists on Arabidopsis space research experiments, aims at establishing a coordinated, long-term scientific strategy to understand the role of gravity in Arabidopsis growth and development using already existing or planned new hardware. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  2. Influence of Plant Population and Nitrogen-Fertilizer at Various Levels on Growth and Growth Efficiency of Maize

    Directory of Open Access Journals (Sweden)

    M. I. Tajul

    2013-01-01

    Full Text Available Field experiments were conducted to evaluate plant population and N-fertilizer effects on yield and yield components of maize (Zea mays L.. Three levels of plant populations (53000, 66000, and 800000 plants ha−1 corresponding to spacings of 75 × 25, 60 × 25, and 50 × 25 cm and 4 doses of N (100, 140, 180, and 220 kg ha−1 were the treatment variables. Results revealed that plant growth, light interception (LI, yield attributes, and grain yield varied significantly due to the variations in population density and N-rates. Crop growth rate (CGR was the highest with the population of 80,000 ha−1 receiving 220 kg N ha−1, while relative growth rate (RGR showed an opposite trend of CGR. Light absorption was maximum when most of densely populated plant received the highest amount of N (220 kg N ha−1. Response of soil-plant-analysis development (SPAD value as well as N-content to N-rates was found significant. Plant height was the maximum at the lowest plant density with the highest amount of N. Plants that received 180 kg N ha−1 with 80,000 plants ha−1 had larger foliage, greater SPAD value, and higher amount of grains cob−1 that contributed to the maximum yield (5.03 t ha−1 and the maximum harvest index (HI compared to the plants in other treatments.

  3. Pectinous cell wall thickenings formation - A common defense strategy of plants to cope with Pb.

    Science.gov (United States)

    Krzesłowska, Magdalena; Rabęda, Irena; Basińska, Aneta; Lewandowski, Michał; Mellerowicz, Ewa J; Napieralska, Anna; Samardakiewicz, Sławomir; Woźny, Adam

    2016-07-01

    Lead, one of the most abundant and hazardous trace metals affecting living organisms, has been commonly detected in plant cell walls including some tolerant plants, mining ecotypes and hyperaccumulators. We have previously shown that in tip growing Funaria sp. protonemata cell wall is remodeled in response to lead by formation of thickenings rich in low-methylesterified pectins (pectin epitope JIM5 - JIM5-P) able to bind metal ions, which accumulate large amounts of Pb. Hence, it leads to the increase of cell wall capacity for Pb compartmentalization. Here we show that diverse plant species belonging to different phyla (Arabidopsis, hybrid aspen, star duckweed), form similar cell wall thickenings in response to Pb. These thickenings are formed in tip growing cells such as the root hairs, and in diffuse growing cells such as meristematic and root cap columella cells of root apices in hybrid aspen and Arabidopsis and in mesophyll cells in star duckweed fronds. Notably, all analyzed cell wall thickenings were abundant in JIM5-P and accumulated high amounts of Pb. In addition, the co-localization of JIM5-P and Pb commonly occurred in these cells. Hence, cell wall thickenings formed the extra compartment for Pb accumulation. In this way plant cells increased cell wall capacity for compartmentalization of this toxic metal, protecting protoplast from its toxicity. As cell wall thickenings occurred in diverse plant species and cell types differing in the type of growth we may conclude that pectinous cell wall thickenings formation is a widespread defense strategy of plants to cope with Pb. Moreover, detection of natural defense strategy, increasing plant cell walls capacity for metal accumulation, reveals a promising direction for enhancing plant efficiency in phytoremediation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Growth strategy of Norway spruce under air elevated [CO2

    Science.gov (United States)

    Pokorny, R.; Urban, O.; Holisova, P.; Sprtova, M.; Sigut, L.; Slipkova, R.

    2012-04-01

    Plants will respond to globally increasing atmospheric CO2 concentration ([CO2]) by acclimation or adaptation at physiological and morphological levels. Considering the temporal onset, physiological responses may be categorized as short-term and morphological ones as long-term responses. The degree of plant growth responses, including cell division and cell expansion, is highly variable. It depends mainly on the specie's genetic predisposition, environment, mineral nutrition status, duration of CO2 enrichment, and/or synergetic effects of other stresses. Elevated [CO2] causes changes in tissue anatomy, quantity, size, shape and spatial orientation and can result in altered sink strength. Since, there are many experimental facilities for the investigation of elevated [CO2] effects on trees: i) closed systems or open top chambers (OTCs), ii) semi-open systems (for example glass domes with adjustable lamella windows - DAWs), and iii) free-air [CO2] enrichments (FACE); the results are still unsatisfactory due to: i) relatively short-term duration of experiments, ii) cultivation of young plants with different growth strategy comparing to old ones, iii) plant cultivation under artificial soil and weather conditions, and iv) in non-representative stand structure. In this contribution we are discussing the physiological and morphological responses of Norway spruce trees cultivated in DAWs during eight consecutive growing seasons in the context with other results from Norway spruce cultivation under air-elevated [CO2] conditions. On the level of physiological responses, we discuss the changes in the rate of CO2 assimilation, assimilation capacity, photorespiration, dark respiration, stomatal conductance, water potential and transpiration, and the sensitivity of these physiological processes to temperature. On the level of morphological responses, we discuss the changes in bud and growth phenology, needle and shoot morphology, architecture of crown and root system, wood

  5. Characterization of Effective Rhizobacteria Isolated from Velvet Bean (Mucuna Pruriens) to Enhance Plant Growth

    International Nuclear Information System (INIS)

    Saleem, A. R.; Mahmood, T.; Batool, A.; Khalid, A.

    2016-01-01

    Rhizobacteria with plant growth promoting ability exist in association with plant roots and ameliorate over all plant development and yield. Numerous species of rhizobacteria have been identified with plant growth promoting ability, which can be attributed to multiple microbial characteristics. In the current study rhizobacterial isolates with best plant growth promotion traits were subjected to screening for plant growth promotion under axenic condition. The results of lab assays revealed that out of five rhizobacterial isolates three of bacterial isolate were Gram -ve and two of them were Gram +ve bacterial group. All isolates found positive for the auxin production and ACC-demainase activity. The isolate HS9 showed highest ACC activity (331 ketobutyrate nmol mg-1 biomass hr-1) and auxin production (3.85 without L-TRP). PGPR increase plant growth by reducing the ethylene release and its inhibitory effects, the role of isolates to decrease ethylene effects was affirmed via classical triple response assay on velvet bean. Furthermore, isolate were assessed for resistance test, three efficient strains (G9, HS9 and H38) exhibited antibiotic resistance for streptomycin, kanamycin and rifampicin at 100 mg L-1in TSB medium. For the purpose of co-inoculation, all three isolates showed positive relation to grow together. The results concluded that rhizobacteria selected from rain fed areas were found effective to improve plant growth with their multiple growth enhancing traits. Therefore, PGPR with various characteristics could be a better option for inoculation and co-inoculation to improve plant growth in well watered and water stressed environment. (author)

  6. Utilization of γ-irradiation technique on plant mutation breeding and plant growth regulation in Tokyo Metropolitan Isotope Research Center

    International Nuclear Information System (INIS)

    Suda, Hirokatsu

    1997-01-01

    During about 30-years, we have developed γ-irradiation technique and breeding back pruning method for the study of mutation breeding of ornamental plants. As a result, we have made a wide variety of new mutant lines in chrysanthemum, narcissus, begonia rex, begonia iron cross, winter daphne, zelkova, sweet-scented oleander, abelia, kobus, and have obtained 7 plant patents. By the use of γ-irradiation to plant mutation breeding, we often observed that plants irradiated by low dose of γ-rays showed superior or inferior growth than the of non-irradiated plants. Now, we established the irradiation conditions of γ-rays for mutation breeding and growth of regulation in narcissus, tulip, Enkianthus perulatus Schneid., komatsuna, moyashi, african violet. In most cases, irradiation dose rate is suggested to be a more important factor to induce plant growth regulators than irradiation dose. (author)

  7. Effect of plant growth-promoting rhizobacteria (PGPRs) on plant growth, yield, and quality of tomato (Lycopersicon esculentum Mill.) under simulated seawater irrigation.

    Science.gov (United States)

    Shen, Min; Jun Kang, Yi; Li Wang, Huan; Sheng Zhang, Xiang; Xin Zhao, Qing

    2012-01-01

    To determine the effects of three PGPRs on plant growth, yield, and quality of tomato under simulated seawater irrigation, a two consecutive seasons' field experiment was conducted in Yancheng Teachers University plot from April to June and August to October, 2011. The results showed that Erwinia persicinus RA2 containing ACC deaminase exhibited the best ability compared with Bacillus pumilus WP8 and Pseudomonas putida RBP1 which had no ACC deaminase activity to enhance marketable yields of fresh and dried fruits in tomato under simulated seawater irrigation especially under HS condition. B. pumilus WP8 had significant effects on improving tomato fruit quality under the conditions of irrigating with 1.0% NaCl solution (MS) and with 2.0% NaCl solution (HS). Na(+) contents were generally accumulated much more in tomato plant mid-shoot leaves than in fruits whatever the salt concentration. More sodium accumulation in leaves of E. persicinus RA2 and B. pumilus WP8 treatments under HS condition were found than in control. E. persicinus RA2 and B. pumilus WP8 can promote tomato growth, improve fruit quality more firmly than P. putida RBP1 during two consecutive seasons. Our study suggested that E. persicinus RA2 and B. pumilus WP8 are considered to be promising PGPR strains which are suited for application in salt marsh planting, ACC deaminase activity was not unique index on screening for PGPRs with the aim of salt stress tolerance, and plant growth promoting activities may be relevant to different growth indices and different stress conditions.

  8. Decision-making in plants under competition

    OpenAIRE

    Gruntman, Michal; Groß, Dorothee; Májeková, Maria; Tielbörger, Katja

    2017-01-01

    Plants can plastically respond to light competition in three strategies, comprising vertical growth, which promotes competitive dominance; shade tolerance, which maximises performance under shade; or lateral growth, which offers avoidance of competition. Here, we test the hypothesis that plants can ‘choose’ between these responses, according to their abilities to competitively overcome their neighbours. We study this hypothesis in the clonal plant Potentilla reptans using an experimental setu...

  9. Increased nutritional quality of plants for long-duration spaceflight missions through choice of plant variety and manipulation of growth conditions

    Science.gov (United States)

    Cohu, Christopher M.; Lombardi, Elizabeth; Adams, William W.; Demmig-Adams, Barbara

    2014-02-01

    Low levels of radiation during spaceflight increase the incidence of eye damage and consumption of certain carotenoids (especially zeaxanthin), via a whole-food-based diet (rather than from supplements), is recommended to protect human vision against radiation damage. Availability of fresh leafy produce has, furthermore, been identified as desirable for morale during long spaceflight missions. We report that only trace amounts of zeaxanthin are retained post-harvest in leaves grown under conditions conducive to rapid plant growth. We show that growth of plants under cool temperatures and very high light can trigger a greater retention of zeaxanthin, while, however, simultaneously retarding plant growth. We here introduce a novel growth condition—low growth light supplemented with several short daily light pulses of higher intensity—that also triggers zeaxanthin retention, but without causing any growth retardation. Moreover, two plant varieties with different hardiness exhibited a different propensity for zeaxanthin retention. These findings demonstrate that growth light environment and plant variety can be exploited to simultaneously optimize nutritional quality (with respect to zeaxanthin and two other carotenoids important for human vision, lutein and β-carotene) as well as biomass production of leafy greens suitable as bioregenerative systems for long-duration manned spaceflight missions.

  10. MAPK-dependent JA and SA signalling in Nicotiana attenuata affects plant growth and fitness during competition with conspecifics

    Science.gov (United States)

    2012-01-01

    Background Induced defense responses to herbivores are generally believed to have evolved as cost-saving strategies that defer the fitness costs of defense metabolism until these defenses are needed. The fitness costs of jasmonate (JA)-mediated defenses have been well documented. Those of the early signaling units mediating induced resistance to herbivores have yet to be examined. Early signaling components that mediate herbivore-induced defense responses in Nicotiana attenuata, have been well characterized and here we examine their growth and fitness costs during competition with conspecifics. Two mitogen-activated protein kinases (MAPKs), salicylic acid (SA)-induced protein kinase (SIPK) and wound-induced protein kinase (WIPK) are rapidly activated after perception of herbivory and both kinases regulate herbivory-induced JA levels and JA-mediated defense metabolite accumulations. Since JA-induced defenses result in resource-based trade-offs that compromise plant productivity, we evaluated if silencing SIPK (irSIPK) and WIPK (irWIPK) benefits the growth and fitness of plants competiting with wild type (WT) plants, as has been shown for plants silenced in JA-signaling by the reduction of Lipoxygenase 3 (LOX3) levels. Results As expected, irWIPK and LOX3-silenced plants out-performed their competing WT plants. Surprisingly, irSIPK plants, which have the largest reductions in JA signaling, did not. Phytohormone profiling of leaves revealed that irSIPK plants accumulated higher levels of SA compared to WT. To test the hypothesis that these high levels of SA, and their presumed associated fitness costs of pathogen associated defenses in irSIPK plants had nullified the JA-deficiency-mediated growth benefits in these plants, we genetically reduced SA levels in irSIPK plants. Reducing SA levels partially recovered the biomass and fitness deficits of irSIPK plants. We also evaluated whether the increased fitness of plants with reduced SA or JA levels resulted from

  11. Phenological growth stages of saffron plant (Crocus sativus L. according to the BBCH Scale

    Directory of Open Access Journals (Sweden)

    Horacio Lopez-Corcoles

    2015-09-01

    Full Text Available Phenological studies are important for understanding the influence of climate dynamics on vegetative growth, flowering and fruiting on plants and can be used in many scientific subjects, such as Agronomy, Botany and Plant Biology, but also Climatology as a result of the current global interest in climate change monitoring. The purpose of the detailed specific culture descriptions of the principal growth stages in plants is to provide an instrument for standardization of data recording. To date, there was no coding method to describe developmental stages on saffron plant (Crocus sativus L.. Because of the increasing world-wide interest on this crop, a novel growth development code based on the BBCH extended scale is proposed in this paper. Six principal growth stages were set up, starting from sprouting, cataphylls and flowers appearance, plant appearance and development, replacement corms development, plant senescence and corm dormancy. Each principal growth stage is subdivided into secondary growth stages. Descriptive keys with illustrations are included to make effective use of the system.

  12. Plant growth regulation by the light of LEDs; LED ko wo tsukatta shokubutsu saibai gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, H. [Mitsubishi Chemical Co., Tokyo (Japan). Yokohama Research Center

    1996-03-01

    Light Emitting Diode (LED) has not only an excellent display function for the luminescent device but also a superior feature without other lamps as light source for plant growth. It was National Aeronautics and Space Administration (NASA) to find out such merit for this light source for plant growth and try at first to use for plant growth at the space. They began to examine the LED application to the light source for the plant growth at the space since a stage at high cost of the LED, to develop some researches centered at cultivation of lettuce, wheat, and others. Finding out future possibility of cost-down of the LEDs on the cost/performance and large merits of the LEDs for control of the plant growth and plant physiology, authors have conducted some cultivation experiments of the plants using the LEDs for light source some years ago. In this papers, characterizations, actual possibility, and future developments of the LEDs for the light sources of the plant growth, are introduced. 5 refs., 4 figs.

  13. The two strategies of plants to cope with chronic low dose irradiation

    International Nuclear Information System (INIS)

    Grodzinsky, D.M.

    2005-01-01

    Full text: The adaptive responses of plants to an increase in radioactivity of environment were established in radiobiological researches carried out in the Zone of the Chernobyl Nuclear Power Station. It has been shown that there are two types of adaptive strategies to the environment contaminated with radionuclides, namely ontogenetic and phylogenetic strategies. The ontogenetic adaptive strategy is attained by induction of DNA reparation. Increasing of the genetic variability in irradiated population performs the phylogenetic adaptive strategy. The mechanism of this strategy is associated with induction of genetic instability. Rise in the frequency of genetic recombination as well as heterozygosity is at the time essential components of phylogenetic adaptation. Ontogenetic and phylogenetic adaptation strategies are an important feature in coping of plants to the elevated chronic irradiation. Most likely plant cells as a stress signal into adaptive responses perceive the low doses of irradiation. (author)

  14. Technical strategy map to employing nuclear power plant aging management

    International Nuclear Information System (INIS)

    Sekimura, Naoto; Kanno, Masanori

    2008-01-01

    Stated in this report are back ground of technical strategy map for nuclear power plant aging management, result of the first road map, significance of technical strategy map, introduction scenario, technology map, road map, upgrade in every year, three groups of academia, industry and government, plan of technical strategy map, upgrade system, comprehensive introduction scenario, measures of nuclear power plant aging management in Japan and the world, new inspection system, outline of 'technical strategy map 2008', preparation of technical information bases in industry, academia and government, collaboration of them, safety researches of neutron radiation damage, stress corrosion crack, fatigue, piping thinning, insulation degradation, concrete degradation, thermal aging, evaluation technologies of earthquake resistance, preparation of rules and standards, ideal maintenance, and training talent. (S.Y.)

  15. Knowledge preservation strategies for nuclear power plants

    International Nuclear Information System (INIS)

    Koruna, S.; Bachmann, H.

    2004-01-01

    The nuclear industry is currently facing several challenges. An internal threat to the safety and operations of nuclear power plants is the loss of those employees who hold knowledge that is either critical to operations or safety. This report discusses the possibilities to preserve knowledge in nuclear power plants. Dependent on the degree of tacitness two different knowledge preservation strategies can be discerned: personalization and codification. The knowledge preservation activities discussed are valued according to the criteria: cost, immediacy of availability and completeness

  16. Environmental Growth Conditions of Trichoderma spp. Affects Indole Acetic Acid Derivatives, Volatile Organic Compounds, and Plant Growth Promotion

    Science.gov (United States)

    Nieto-Jacobo, Maria F.; Steyaert, Johanna M.; Salazar-Badillo, Fatima B.; Nguyen, Dianne Vi; Rostás, Michael; Braithwaite, Mark; De Souza, Jorge T.; Jimenez-Bremont, Juan F.; Ohkura, Mana; Stewart, Alison

    2017-01-01

    Trichoderma species are soil-borne filamentous fungi widely utilized for their many plant health benefits, such as conferring improved growth, disease resistance and abiotic stress tolerance to their hosts. Many Trichoderma species are able to produce the auxin phytohormone indole-3-acetic acid (IAA), and its production has been suggested to promote root growth. Here we show that the production of IAA is strain dependent and diverse external stimuli are associated with its production. In in vitro assays, Arabidopsis primary root length was negatively affected by the interaction with some Trichoderma strains. In soil experiments, a continuum effect on plant growth was shown and this was also strain dependent. In plate assays, some strains of Trichoderma spp. inhibited the expression of the auxin reporter gene DR5 in Arabidopsis primary roots but not secondary roots. When Trichoderma spp. and A. thaliana were physically separated, enhancement of both shoot and root biomass, increased root production and chlorophyll content were observed, which strongly suggested that volatile production by the fungus influenced the parameters analyzed. Trichoderma strains T. virens Gv29.8, T. atroviride IMI206040, T. sp. “atroviride B” LU132, and T. asperellum LU1370 were demonstrated to promote plant growth through volatile production. However, contrasting differences were observed with LU1370 which had a negative effect on plant growth in soil but a positive effect in plate assays. Altogether our results suggest that the mechanisms and molecules involved in plant growth promotion by Trichoderma spp. are multivariable and are affected by the environmental conditions. PMID:28232840

  17. Non-Contact Plant Growth Measurement Method and System Based on Ubiquitous Sensor Network Technologies

    Directory of Open Access Journals (Sweden)

    Intae Ryoo

    2011-04-01

    Full Text Available This paper proposes a non-contact plant growth measurement system using infrared sensors based on the ubiquitous sensor network (USN technology. The proposed system measures plant growth parameters such as the stem radius of plants using real-time non-contact methods, and generates diameter, cross-sectional area and thickening form of plant stems using this measured data. Non-contact sensors have been used not to cause any damage to plants during measurement of the growth parameters. Once the growth parameters are measured, they are transmitted to a remote server using the sensor network technology and analyzed in the application program server. The analyzed data are then provided for administrators and a group of interested users. The proposed plant growth measurement system has been designed and implemented using fixed-type and rotary-type infrared sensor based measurement methods and devices. Finally, the system performance is compared and verified with the measurement data that have been obtained by practical field experiments.

  18. Effects of plant growth regulators in heliconia ‘Red Opal’

    Directory of Open Access Journals (Sweden)

    Ana Cecilia Ribeiro de Castro

    2016-12-01

    Full Text Available The objective of this study was to evaluate growth regulators with purpose of reducing the size of heliconia ‘Red Opal’ potted plants. The experiment was carried out in randomized block design with five treatments (trinexapac-ethyl and paclobutrazol at rates of 37.5 and 75.0 mg of active ingredient per pot and control without growth regulator and five replicates. The treatments were applied 40 days after planting the rhizomes in pots filled with soil. Thirty and 150 days after the growth regulator application, plant height, number of leaves and shoots, petioles length and leaf area were evaluated. One year after planting the rhizomes in pots the number of inflorescence and leaves (leaves, sheathing leaf bases and inflorescences and rhizomes (rhizomes and roots dry mass were determined. Trinexapac-ethyl had no differences compared to the control in any of the variables evaluated. Paclobutrazol proved effective in reducing plant height, leaf area and petiole length and increase in number of leaves and shoots but the effect was temporary. Also, it did not affect the inflorescences production and leaves and rhizomes dry mass. Paclobutrazol is efficient to promote height reduction and to increase the number of shoots in heliconia ‘Red Opal’ potted plants without affect the inflorescence formation but its effects is temporary.

  19. Effects of gasification biochar on plant-available water capacity and plant growth in two contrasting soil types

    DEFF Research Database (Denmark)

    Hansen, Veronika; Hauggaard-Nielsen, Henrik; Petersen, Carsten Tilbæk

    2016-01-01

    Abstract Gasification biochar (GB) contains recalcitrant carbon that can contribute to soil carbon sequestration and soil quality improvement. However, the impact of GB on plant-available water capacity (AWC) and plant growth in diverse soil types still needs to be explored. A pot experiment......, the reduced water regime significantly affected plant growth and water consumption, whereas the effect was less pronounced in the coarse sand. Irrespective of the soil type, both GBs increased AWC by 17–42%, with the highest absolute effect in the coarse sand. The addition of SGB to coarse sand led...

  20. Plant-based anti-HIV-1 strategies: vaccine molecules and antiviral approaches.

    Science.gov (United States)

    Scotti, Nunzia; Buonaguro, Luigi; Tornesello, Maria Lina; Cardi, Teodoro; Buonaguro, Franco Maria

    2010-08-01

    The introduction of highly active antiretroviral therapy has drastically changed HIV infection from an acute, very deadly, to a chronic, long-lasting, mild disease. However, this requires continuous care management, which is difficult to implement worldwide, especially in developing countries. Sky-rocketing costs of HIV-positive subjects and the limited success of preventive recommendations mean that a vaccine is urgently needed, which could be the only effective strategy for the real control of the AIDS pandemic. To be effective, vaccination will need to be accessible, affordable and directed against multiple antigens. Plant-based vaccines, which are easy to produce and administer, and require no cold chain for their heat stability are, in principle, suited to such a strategy. More recently, it has been shown that even highly immunogenic, enveloped plant-based vaccines can be produced at a competitive and more efficient rate than conventional strategies. The high variability of HIV epitopes and the need to stimulate both humoral neutralizing antibodies and cellular immunity suggest the importance of using the plant system: it offers a wide range of possible strategies, from single-epitope to multicomponent vaccines, modulators of the immune response (adjuvants) and preventive molecules (microbicides), either alone or in association with plant-derived monoclonal antibodies, besides the potential use of the latter as therapeutic agents. Furthermore, plant-based anti-HIV strategies can be administered not only parenterally but also by the more convenient and safer oral route, which is a more suitable approach for possible mass vaccination.

  1. Contrasting growth responses of dominant peatland plants to warming and vegetation composition.

    Science.gov (United States)

    Walker, Tom N; Ward, Susan E; Ostle, Nicholas J; Bardgett, Richard D

    2015-05-01

    There is growing recognition that changes in vegetation composition can strongly influence peatland carbon cycling, with potential feedbacks to future climate. Nevertheless, despite accelerated climate and vegetation change in this ecosystem, the growth responses of peatland plant species to combined warming and vegetation change are unknown. Here, we used a field warming and vegetation removal experiment to test the hypothesis that dominant species from the three plant functional types present (dwarf-shrubs: Calluna vulgaris; graminoids: Eriophorum vaginatum; bryophytes: Sphagnum capillifolium) contrast in their growth responses to warming and the presence or absence of other plant functional types. Warming was accomplished using open top chambers, which raised air temperature by approximately 0.35 °C, and we measured air and soil microclimate as potential mechanisms through which both experimental factors could influence growth. We found that only Calluna growth increased with experimental warming (by 20%), whereas the presence of dwarf-shrubs and bryophytes increased growth of Sphagnum (46%) and Eriophorum (20%), respectively. Sphagnum growth was also negatively related to soil temperature, which was lower when dwarf-shrubs were present. Dwarf-shrubs may therefore promote Sphagnum growth by cooling the peat surface. Conversely, the effect of bryophyte presence on Eriophorum growth was not related to any change in microclimate, suggesting other factors play a role. In conclusion, our findings reveal contrasting abiotic and biotic controls over dominant peatland plant growth, suggesting that community composition and carbon cycling could be modified by simultaneous climate and vegetation change.

  2. Energy conservation and management strategies in Heavy Water Plants

    International Nuclear Information System (INIS)

    Kamath, H.S.

    2002-01-01

    In the competitive industrial environment it is essential that cost of the product is kept at the minimum possible. Energy conservation is an important aspect in achieving this as energy is one of the key recourses for growth and survival of industry. The process of heavy water production being very complex and energy intensive, Heavy Water board has given a focussed attention for initiating various measures for reducing the specific energy consumption in all the plants. The initiative resulted in substantial reduction in specific energy consumption and brought in savings in cost. The cumulative reduction of specific energy consumption has been over 30% over the last seven years and the total savings for the last three years on account of the same has been about Rs. 190 crore. The paper describes the strategies adopted in the heavy water plants for effecting the above achievements. The paper covers the details of some of the energy saving schemes carried out at different heavy water plants through case studies. The case studies of schemes implemented at HWPs are general in nature and is applicable for any other industry. The case studies cover the modifications with re-optimisation of the process parameters, improvements effected in utility units like refrigeration and cooling water systems, improvements in captive power plant cycle and improved recycle scheme for water leading to reduced consumptions. The paper also mentions the innovative ammonia absorption refrigeration with improved coefficient of performance and HWB's efforts in development of the system as an integrated unit of the ammonia water deuterium exchange process for heavy water production. HWB also has taken up R and D on various other schemes for improvements in energy consumption for future activities covering utilisation of low grade energy for generation of refrigeration. (author)

  3. MORPHOLOGICAL AND PHYSIOLOGICAL CHARACTERISTICS OF GROWTH AND DEVELOPMENT OF PLANTS IN HIGH SALINITY

    Directory of Open Access Journals (Sweden)

    O. M. Vasilyuk

    2015-10-01

    Full Text Available The effect of increasing salinity to the morpho-metric parameters of Salix alba L., which dominated in the coastal areas on rivers of Steppe Dnieper, is investigated. We added Mg as salt MgSO4 * 3H2O in the range of concentration: 0.5, 1.0, 1.5, 2.0 and 2.5 g/l in a solution of willow cuttings. In the solution was added and plant growth regulator "Kornevin" the synthetic origin. The negative effect of salt at a concentration from 1.0 g/l to 2.5 g/l in the dynamics of growth and development was found. The correlation between the size and salinity in dynamics of growth and development of plant were demonstrated: in the growth of shoots (R = 0.83, 0.91 and 0.95, in the growth of roots (R = 0.92, 0.68 and 0.84 respectively depended from salt concentration. The length of the leaf blade was from 4% to 8%, from 7% to 43%, from 333% to 11% (R = 0,68, 0,93, 0,61, depending on the concentration of salt and during observing compared with control (distilled water. "Kornevin" and combined effect of salt increased the length of the leaf blade growth by 4-5, 2-4, 3-5 times, the roots by7 and 3-14 times, the shoots by 3-4, 6-7 and 5-7 times in the dynamics of growth compared with control (MgSO4, 2,5 g/l. The recommendations regarding for the advisability of using the plant growth regulator "Kornevin", as very effective plant growth preparation that promoted rooting and activated physiological processes of plant organism, expressed protective effect in conditions of excessive salinity, were provided. Key words: the morpho-metric index, the plant growth regulators, abiotic factors, salinity factor, the adaptation.

  4. Screening of Plant Growth-Promoting Rhizobacteria from Maize ...

    African Journals Online (AJOL)

    Screening of Plant Growth-Promoting Rhizobacteria from Maize ( Zea Mays ) and Wheat ( Triticum Aestivum ) ... PROMOTING ACCESS TO AFRICAN RESEARCH. AFRICAN ... African Journal of Food, Agriculture, Nutrition and Development.

  5. Plant growth and development vs. high and low levels of plant-beneficial heavy metal ions

    Directory of Open Access Journals (Sweden)

    Namira Arif

    2016-11-01

    Full Text Available Heavy metals (HMs exists in the environment in both forms as essential and non-essential. These HM ions enter in soil biota from various sources like natural and anthropogenic. Essential HMs such as cobalt (Co, copper (Cu, iron (Fe, manganese (Mn, molybdenum (Mo, nickel (Ni, and zinc (Zn plays a beneficial role in plant growth and development. At optimum level these beneficial elements improves the plant’s nutritional level and also several mechanisms essential for the normal growth and better yield of plants. The range of their optimality for land plants is varied. Plant uptake heavy metals as a soluble component or solubilized them by root exudates. While their presence in excess become toxic for plants that switches the plant’s ability to uptake and accumulate other nonessential elements. The increased amount of HMs within the plant tissue displays direct and indirect toxic impacts. Such direct effects are the generation of oxidative stress which further aggravates inhibition of cytoplasmic enzymes and damage to cell structures. Although, indirect possession is the substitution of essential nutrients at plant’s cation exchange sites. These ions readily influence role of various enzymes and proteins, arrest metabolism, and reveal phytotoxicity. On account of recent advancements on beneficial HMs ions Co, Cu, Fe, Mn, Mo, Ni, and Zn in soil-plant system, the present paper: overview the sources of HMs in soils and their uptake and transportation mechanism, here we have discussed the role of metal transporters in transporting the essential metal ions from soil to plants. The role played by Co, Cu, Fe, Mn, Mo, Ni, and Zn at both low and high level on the plant growth and development and the mechanism to alleviate metal toxicity at high level have been also discussed. At the end, on concluding the article we have also discussed the future perspective in respect to beneficial HM ions interaction with plant at both levels.

  6. Effect on growth and nickel content of cabbage plants watered with nickel solutions

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, O B

    1979-01-01

    Chinese cabbage plants were watered with different concentrations of NiCl/sub 2/ solutions and the effect on growth and uptake of nickel in the plants were studied. No toxic effect on plant growth was observed. A higher content of nickel was found in the plants exposed to more concentrated nickel solutions. Nickel contamination and its clinical consequences are discussed. 29 references, 1 figure, 1 table.

  7. Interactive effects of above- and belowground herbivory and plant competition on plant growth and defence

    NARCIS (Netherlands)

    Jing, Y.; Raaijmakers, C.; Kostenko, O.; Kos, M.; Mulder, P.P.J.; Bezemer, T.M.

    2015-01-01

    Competition and herbivory are two major factors that can influence plant growth and plant defence. Although these two factors are often studied separately, they do not operate independently. We examined how aboveground herbivory by beet armyworm larvae (Spodoptera exigua) and belowground herbivory

  8. Growth and Development of Three-Dimensional Plant Form.

    Science.gov (United States)

    Whitewoods, Christopher D; Coen, Enrico

    2017-09-11

    Plants can generate a spectacular array of complex shapes, many of which exhibit elaborate curvature in three dimensions, illustrated for example by orchid flowers and pitcher-plant traps. All of these structures arise through differential growth. Recent findings provide fresh mechanistic insights into how regional cell behaviours may lead to tissue deformations, including anisotropies and curvatures, which shape growing volumes and sheets of cells. Here were review our current understanding of how genes, growth, mechanics, and evolution interact to generate diverse structures. We illustrate problems and approaches with the complex three-dimensional trap of the bladderwort, Utricularia gibba, to show how a multidisciplinary approach can be extended to new model systems to understand how diverse plant shapes can develop and evolve. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. (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.

  10. Impacts of priming with silicon on the growth and tolerance of maize plants to alkaline stress

    Directory of Open Access Journals (Sweden)

    ِArafat eAbdel Latef

    2016-03-01

    Full Text Available Silicon (Si has been known to augment plant defense against biotic and abiotic pressures. Maize (Zea maize L. is classified as a Si accumulator and is relatively susceptible to alkaline stress. In this work, grains of maize were grown in pots and exposed to various concentrations of Na2CO3 (0, 25, 50 and 75 mM with or without 1.5 mM Si in the form of sodium metasilicate Na2O3Si.5H2O for 25 days. Alkaline-stressed plants showed a decrease in growth parameters, leaf relative water content (LRWC, and the contents of photosynthetic pigments, soluble sugars, total phenols and potassium ion (K+, as well as potassium/sodium ion (K+/Na+ ratio. By contrast, alkaline stress increased the contents of soluble proteins, total free amino acids, proline, Na+ and malondialdehyde (MDA, as well as the activities of superoxide dismutase (SOD, catalase (CAT and peroxidase (POD in stressed plants. On the other hand, application of Si by grain priming improved growth of stressed plants, which was accompanied by the enhancement in LRWC, levels of photosynthetic pigments, soluble sugars, soluble proteins, total free amino acids, K+ and activities of SOD, CAT and POD enzymes. Furthermore, Si supplement resulted in a decrease in the contents of proline, MDA and Na+, which together with enhanced K+ level led to a favorable adjustment of K+/Na+ ratio, in stressed plants relative to plants treated with alkaline stress alone. Taken together, these results indicate that Si plays a pivotal role in alleviating the negative effects of alkaline stress on the maize growth by improving water status, enhancing photosynthetic pigments, accumulating osmoprotectants rather than proline, activating the antioxidant machinery, and maintaining the balance of K+/Na+. Thus, our findings demonstrate that seed priming with Si is an efficient strategy that can be used to boost tolerance of maize plants to alkaline stress.

  11. Tolerance of transgenic canola plants (Brassica napus) amended with plant growth-promoting bacteria to flooding stress at a metal-contaminated field site

    International Nuclear Information System (INIS)

    Farwell, Andrea J.; Vesely, Susanne; Nero, Vincent; Rodriguez, Hilda; McCormack, Kimberley; Shah, Saleh; Dixon, D. George; Glick, Bernard R.

    2007-01-01

    The growth of transgenic canola (Brassica napus) expressing a gene for the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase was compared to non-transformed canola exposed to flooding and elevated soil Ni concentration, in situ. In addition, the ability of the plant growth-promoting bacterium Pseudomonas putida UW4, which also expresses ACC deaminase, to facilitate the growth of non-transformed and transgenic canola under the above mentioned conditions was examined. Transgenic canola and/or canola treated with P. putida UW4 had greater shoot biomass compared to non-transformed canola under low flood-stress conditions. Under high flood-stress conditions, shoot biomass was reduced and Ni accumulation was increased in all instances relative to low flood-stress conditions. This is the first field study to document the increase in plant tolerance utilizing transgenic plants and plant growth-promoting bacteria exposed to multiple stressors. - Using transgenic plants and plant growth-promoting bacteria as phytoremediation methods increased plant tolerance at a metal-contaminated field site under low flood conditions

  12. PGPR Potentially Improve Growth of Tomato Plants in Salt-Stressed Environment

    Directory of Open Access Journals (Sweden)

    Mariam Zameer

    2016-06-01

    Full Text Available Plant growth promoting rhizobacteria are colonized bacterial species that has the capability to improve plant growth by certain direct and indirect means. Environmental factors including both biotic and abiotic stresses are among the major constraints to crop production. In the current study, the effectiveness of microbial inoculation (Bacillus megaterium for enhancing growth of tomato plants under salt stress conditions has been investigated. Significant improvement in shoot length, root length, leaf surface area, number of leaves, total weight of the shoot and root was observed in tomato plants inoculated with zm7 strain post 15 and 30 days of its application. Zm3, Zm4 and Zm6 strains improved the morphological parameters as compared to the control. Chlorophyll content a, chlorophyll content b, anthocyanin and carotenoid content was increased in tomato plants subjected to Zm7, Zm6 and Zm4 strains. Stress responsive genes; metallothionein and glutothion gene were found highly expressed in Zm7 treated tomato plants as compared to control, untreated plants. Significant correlation of anthocyanin was reported for carotenoids, chlorophyll-b, shoot weight and total weight of seedling while carotenoids were significantly correlated with leaf surface area, root length, chlorophyll-b and anthocyanin. Overall, Zm7 strain proved best for improvement in salt stressed plant’s morphological parameters and biochemical parameters as compared to control, untreated plants.

  13. Effect of vanadium on plant growth and its accumulation in plant tissues

    Directory of Open Access Journals (Sweden)

    Narumol Vachirapatama

    2011-06-01

    Full Text Available Hydroponic experiments were conducted to investigate vanadium uptake by Chinese green mustard and tomato plantsand its effect on their growth. Twenty-eight (Chinese green mustard and 79 days (tomato after germination, the plants wereexposed for a further seven days to a solution containing six different concentrations of ammonium metavanadate (0-80 mg/lNH4VO3. The vanadium accumulated in the plant tissues were determined by ion-interaction high performance liquid chromatography,with confirmation by magnetic sector ICP-MS.The results indicated that nutrient solution containing more than 40 mg/l NH4VO3 affected plant growth for bothChinese green mustard and tomato plant. Chinese green mustard grown in the solution containing NH4VO3 at the concentrationsof 40 and 80 mg/l had stem length, number of leaves, dry weight of leaf, stem and root significantly lower than those ofplants grown in the solution containing 0-20 mg/l NH4VO3. Tomato plants were observed to wilt after four days in contactwith the nutrient solutions containing 40 and 80 mg/l NH4VO3. As the vanadium concentrations increased, a resultantdecrease in the stem length, root fresh weight, and fruit fresh weight were noted. The accumulation of vanadium was higher inthe root compared with leaf, stem, or fruit. Measured levels of vanadium, from a nutrient solution containing 40 mg/l NH4VO3,were 328, 340, and 9.66x103 g/g in the leaf, stem and root for Chinese green mustard, and 4.04 and 4.01x103 g/g in the fruitand roots for tomato plants, respectively.

  14. Phosphate solubilization and multiple plant growth promoting ...

    African Journals Online (AJOL)

    Phosphate solubilizing efficiencies of the strains were analyzed using different insoluble phosphorus sources and the results show that most isolates released a substantial amount of soluble phosphate from tricalcium phosphate, rock phosphate and bone meal. Screening for multiple plant growth promoting attributes ...

  15. The influence of humic acids derived from earthworm-processed organic wastes on plant growth

    Energy Technology Data Exchange (ETDEWEB)

    Atiyeh, R.M.; Lee, S.; Edwards, C.A.; Arancon, N.Q.; Metzger, J.D. [Ohio State University, Columbus, OH (United States). Soil Ecology Lab.

    2002-08-01

    Some effects of humic acids, formed during the breakdown of organic wastes by earthworms (vermicomposting), on plant growth were evaluated. In the first experiment, humic acids were extracted from pig manure vermicompost using the classic alkali/acid fractionation procedure and mixed with a soilless container medium (Metro-Mix 360), to provide a range of 0, 50, 100, 150, 200, 250, 500, 1000, 2000 and 4000 mg of humate per kg of dry weight of container medium, and tomato seedlings were grown in the mixtures. In the second experiment, humates extracted from pig manure and food wastes vermicomposts were mixed with vermiculite to provide a range of 0, 50, 125, 250, 500, 1000 and 4000 mg of humate per kg of dry weight of the container medium, and cucumber seedlings were grown in the mixtures. Both tomato and cucumber seedlings were watered daily with a solution containing all nutrients required to ensure that any differences in growth responses were not nutrient-mediated. The incorporation of both types of vermicompost-derived humic acids, into either type of soilless plant growth media, increased the growth of tomato and cucumber plants significantly, in terms of plant heights, leaf areas, shoot and root dry weights. Plant growth increased with increasing concentrations of humic acids incorporated into the medium up to a certain proportion, but this differed according to the plant species, the source of the vermicompost, and the nature of the container medium. Plant growth tended to be increased by treatments of the plants with 50-500 mg/kg humic acids, but often decreased significantly when the concentrations of humic acids derived in the container medium exceeded 500-1000 mg/kg. These growth responses were most probably due to hormone-like activity of humic acids from the vermicomposts or could have been due to plant growth hormones adsorbed onto the humates. (author)

  16. Restoring directional growth sense to plants in space

    Science.gov (United States)

    Gorgolewski, S.

    Introduction of new plant classification: electrotropic (Et) and non-electrotropic (nEt) plants gives us a criterion which plants need electric field to grow "normally" in space. The electric field: E is measured in V/m (volt per meter). Do not confuse "electrotropism" understood by some as the response to current flow transversely through the plant's root. This effect was previously described in biological textbooks. I suggest to call it as (Ct) (here C stands for current and t for tropism). In the laboratory we have in the plant growth chamber two transparent to light (wire mesh) conducting sheets separated by m(meters) and V volts potential difference. It has been shown in laboratory that Et is a very important factor in electrotropic plant development. Space experiments with plants grown in orbit from seed to seed have been fully successful only (in my very best knowledge) with nEt plants. The most common nEt plants are grasses (more than 50% of all plants). The nEt plants in space use phototropism as their sensor of direction. In space (and most greenhouses) we have to provide the electric field at least for the Et plants. It has been shown that the electric field is also beneficial to nEt plants which also acquire the sense of direction imposed by stronger than the normal 130V/m E field (vector). The stronger horizontal E field of 1.6kV/m (slightly more than 12 times stronger than 130V/m) does not influence the rate of growth of maize (which is nEt) in 130V/m vertical field or even in the Faraday cage 0V/m. Yet when the maize gets its leaves, they all lean in the horizontal field (1.6kV/m) towards the anode. The direction of the E vector is defined by the E field lines running from the positive to the negative charges. Because the electric forces are a factor of 1038 times stronger than the gravitational forces, it is not important for the E field whether it acts on ions in the gravity or in weightlessness. We have to recall that on the Earth and in space Et

  17. Plant growth responses of apple and pear trees to doses of glyphosate

    Science.gov (United States)

    Glyphosate is commonly used for intra-row weed management in perennial plantations, where unintended crop exposure to this herbicide can cause growth reduction. The objective of this research was to analyze the initial plant growth behavior of young apple and pear plants exposed to glyphosate. Glyph...

  18. Potential of plant growth promoting rhizobacteria and chemical fertilizers on soil enzymes and plant growth

    International Nuclear Information System (INIS)

    Nosheen, A.; Bano, A.

    2014-01-01

    The present investigation deals with the role of Plant Growth Promoting Rhizobacteria and chemical fertilizers alone or in combination on urease, invertase and phosphatase activities of rhizospheric soil and also on general impact on growth of safflower cvv. Thori and Saif-32. The PGPR (Azospirillum brasilense and Azotobacter vinelandii) were applied at 10/sup 6/ cells/mL as seed inoculation prior to sowing. Chemical fertilizers were applied at full (Urea 60 Kg ha/sup -1/ and Diammonium phosphate (DAP) 30 Kg ha/sup -1/), half (Urea 30 Kg ha/sup -1/ and DAP 15 Kg ha/sup -1/) and quarter doses (Urea 15 Kg ha-1 and DAP 7.5 Kg ha/sup -1/) during sowing. The chemical fertilizers and PGPR enhanced urease and invertase activities of soil. Presence of PGPR in combination with quarter and half doses of chemical fertilizers further augmented their effect on soil enzymes activities. The soil phosphatase activity was greater in Azospirillum and Azotobacter in combination with half dose of chemical fertilizers. Maximum increase in leaf melondialdehyde content was recorded in full dose of chemical fertilizers whereas coinoculation treatment exhibited significant reduction in cv. Thori. Half and quarter dose of chemical fertilizers increased the shoot length of safflower whereas maximum increase in leaf protein was recorded in Azotobacter in combination with full dose of chemical fertilizers. Root length was improved by Azospirillum and Azotobacter in combination with quarter dose of chemical fertilizers. Leaf area and chlorophyll contents were significantly improved by Azotobacter in combination with half dose of chemical fertilizers. It is inferred that PGPR can supplement 50 % chemical fertilizers for better plant growth and soil health. (author)

  19. Characterization of Plant Growth under Single-Wavelength Laser Light Using the Model Plant Arabidopsis Thaliana

    KAUST Repository

    Ooi, Amanda

    2016-12-01

    Indoor horticulture offers a promising solution for sustainable food production and is becoming increasingly widespread. However, it incurs high energy and cost due to the use of artificial lighting such as high-pressure sodium lamps, fluorescent light or increasingly, the light-emitting diodes (LEDs). The energy efficiency and light quality of currently available lighting is suboptimal, therefore less than ideal for sustainable and cost-effective large-scale plant production. Here, we demonstrate the use of high-powered single-wavelength lasers for indoor horticulture. Lasers are highly energy-efficient and can be remotely guided to the site of plant growth, thus reducing on-site heat accumulation. Besides, laser beams can be tailored to match the absorption profiles of different plants. We have developed a prototype laser growth chamber and demonstrate that laser-grown plants can complete a full growth cycle from seed to seed with phenotypes resembling those of plants grown under LEDs. Importantly, the plants have lower expression of proteins diagnostic for light and radiation stress. The phenotypical, biochemical and proteomic data show that the singlewavelength laser light is suitable for plant growth and therefore, potentially able to unlock the advantages of this next generation lighting technology for highly energy-efficient horticulture. Furthermore, stomatal movement partly determines the plant productivity and stress management. Abscisic acid (ABA) induces stomatal closure by promoting net K+-efflux from guard cells through outwardrectifying K+ (K+ out) channels to regulate plant water homeostasis. Here, we show that the Arabidopsis thaliana guard cell outward-rectifying K+ (ATGORK) channel is a direct target for ABA in the regulation of stomatal aperture and hence gas exchange and transpiration. Addition of (±)-ABA, but not the biologically inactive (−)-isomer, increases K+ out channel activity in Vicia faba guard cell protoplast. A similar ABA

  20. New insights into the cellular mechanisms of plant growth at elevated atmospheric carbon dioxide.

    Science.gov (United States)

    Gamage, Dananjali; Thompson, Michael; Sutherland, Mark; Hirotsu, Naoki; Makino, Amane; Seneweera, Saman

    2018-04-02

    Rising atmospheric carbon dioxide concentration ([CO 2 ]) significantly influences plant growth, development and biomass. Increased photosynthesis rate, together with lower stomatal conductance, have been identified as the key factors that stimulate plant growth at elevated [CO 2 ] (e[CO 2 ]). However, variations in photosynthesis and stomatal conductance alone cannot fully explain the dynamic changes in plant growth. Stimulation of photosynthesis at e[CO 2 ] is always associated with post-photosynthetic secondary metabolic processes that include carbon and nitrogen metabolism, cell cycle functions and hormonal regulation. Most studies have focused on photosynthesis and stomatal conductance in response to e[CO 2 ], despite the emerging evidence of e[CO 2 ]'s role in moderating secondary metabolism in plants. In this review, we briefly discuss the effects of e[CO 2 ] on photosynthesis and stomatal conductance and then focus on the changes in other cellular mechanisms and growth processes at e[CO 2 ] in relation to plant growth and development. Finally, knowledge gaps in understanding plant growth responses to e[CO 2 ] have been identified with the aim of improving crop productivity under a CO 2 rich atmosphere. This article is protected by copyright. All rights reserved.

  1. Effect of plant growth regulators on production of alpha-linolenic ...

    Indian Academy of Sciences (India)

    Sujana Kokkiligadda

    2017-10-05

    Oct 5, 2017 ... MS received 13 October 2016; revised 22 March 2017; accepted 30 May 2017; ... Plant growth regulators; microalgae; Chlorella pyrenoidosa; alpha-linolenic acid. 1. ... the growth period by flocculation method [9] using alum.

  2. Influence of water relations and growth rate on plant element uptake and distribution

    International Nuclear Information System (INIS)

    Greger, Maria

    2006-02-01

    Plant uptake of Ni, Sr, Mo, Cs, La, Th, Se, Cl and I was examined to determine how plant water relations and growth rate influence the uptake and distribution of these elements in the studied plants. The specific questions were how water uptake and growth rate influenced the uptake of various nuclides and how transpiration influenced translocation to the shoot. The knowledge gained will be used in future modelling of radionuclide leakage from nuclear waste deposits entering the ecosystem via plants. The plant studied was willow, Salix viminalis, a common plant in the areas suggested for waste disposal; since there can be clone variation, two different clones having different uptake properties for several other heavy metals were used. The plants were grown in nutrient solution and the experiments on 3-month-old plants were run for 3 days. Polyethylene glycol was added to the medium to decrease the water uptake rate, a fan was used to increase the transpiration rate, and different light intensities were used to produce different growth rates. Element concentration was analysed in roots and shoots. The results show that both the uptake and distribution of various elements are influenced in different ways and to various extents by water flow and plant growth rate, and that it is not possible from the chemical properties of these elements to know how they will react. However, in most cases increased growth rate diluted the concentration of the element in the tissue, reduced water uptake reduced the element uptake, while transpiration had no effect on the translocation of elements to the shoot. The clones did not differ in terms of either the uptake or translocation of the elements, except that I was not taken up and translocated to the shoot in one of the clones when the plant water flow or growth rate was too low. Not all of the elements were found in the plant in the same proportions as they had been added to the nutrient solution

  3. Influence of water relations and growth rate on plant element uptake and distribution

    Energy Technology Data Exchange (ETDEWEB)

    Greger, Maria [Stockholm Univ. (Sweden). Dept. of Botany

    2006-02-15

    Plant uptake of Ni, Sr, Mo, Cs, La, Th, Se, Cl and I was examined to determine how plant water relations and growth rate influence the uptake and distribution of these elements in the studied plants. The specific questions were how water uptake and growth rate influenced the uptake of various nuclides and how transpiration influenced translocation to the shoot. The knowledge gained will be used in future modelling of radionuclide leakage from nuclear waste deposits entering the ecosystem via plants. The plant studied was willow, Salix viminalis, a common plant in the areas suggested for waste disposal; since there can be clone variation, two different clones having different uptake properties for several other heavy metals were used. The plants were grown in nutrient solution and the experiments on 3-month-old plants were run for 3 days. Polyethylene glycol was added to the medium to decrease the water uptake rate, a fan was used to increase the transpiration rate, and different light intensities were used to produce different growth rates. Element concentration was analysed in roots and shoots. The results show that both the uptake and distribution of various elements are influenced in different ways and to various extents by water flow and plant growth rate, and that it is not possible from the chemical properties of these elements to know how they will react. However, in most cases increased growth rate diluted the concentration of the element in the tissue, reduced water uptake reduced the element uptake, while transpiration had no effect on the translocation of elements to the shoot. The clones did not differ in terms of either the uptake or translocation of the elements, except that I was not taken up and translocated to the shoot in one of the clones when the plant water flow or growth rate was too low. Not all of the elements were found in the plant in the same proportions as they had been added to the nutrient solution.

  4. Compound Synthesis or Growth and Development of Roots/Stomata Regulate Plant Drought Tolerance or Water Use Efficiency/Water Uptake Efficiency.

    Science.gov (United States)

    Meng, Lai-Sheng

    2018-04-11

    Water is crucial to plant growth and development because it serves as a medium for all cellular functions. Thus, the improvement of plant drought tolerance or water use efficiency/water uptake efficiency is important in modern agriculture. In this review, we mainly focus on new genetic factors for ameliorating drought tolerance or water use efficiency/water uptake efficiency of plants and explore the involvement of these genetic factors in the regulation of improving plant drought tolerance or water use efficiency/water uptake efficiency, which is a result of altered stomata density and improving root systems (primary root length, hair root growth, and lateral root number) and enhanced production of osmotic protectants, which is caused by transcription factors, proteinases, and phosphatases and protein kinases. These results will help guide the synthesis of a model for predicting how the signals of genetic and environmental stress are integrated at a few genetic determinants to control the establishment of either water use efficiency or water uptake efficiency. Collectively, these insights into the molecular mechanism underpinning the control of plant drought tolerance or water use efficiency/water uptake efficiency may aid future breeding or design strategies to increase crop yield.

  5. Potential effects of plant growth promoting rhizobacteria ...

    African Journals Online (AJOL)

    Damping off caused by Sclerotium rolfsii on cowpea results in yield losses with serious socioeconomic implication. Induction of defense responses by plant growth promoting rhizobacteria (PGPR) is largely associated with the production of defense enzyme phenyl ammonia lyase (PAL) and oxidative enzymes like ...

  6. Genome Sequence of the Plant Growth Promoting Endophytic Bacterium Enterobacter sp. 638

    Science.gov (United States)

    Taghavi, Safiyh; van der Lelie, Daniel; Hoffman, Adam; Zhang, Yian-Biao; Walla, Michael D.; Vangronsveld, Jaco; Newman, Lee; Monchy, Sébastien

    2010-01-01

    Enterobacter sp. 638 is an endophytic plant growth promoting gamma-proteobacterium that was isolated from the stem of poplar (Populus trichocarpa×deltoides cv. H11-11), a potentially important biofuel feed stock plant. The Enterobacter sp. 638 genome sequence reveals the presence of a 4,518,712 bp chromosome and a 157,749 bp plasmid (pENT638-1). Genome annotation and comparative genomics allowed the identification of an extended set of genes specific to the plant niche adaptation of this bacterium. This includes genes that code for putative proteins involved in survival in the rhizosphere (to cope with oxidative stress or uptake of nutrients released by plant roots), root adhesion (pili, adhesion, hemagglutinin, cellulose biosynthesis), colonization/establishment inside the plant (chemiotaxis, flagella, cellobiose phosphorylase), plant protection against fungal and bacterial infections (siderophore production and synthesis of the antimicrobial compounds 4-hydroxybenzoate and 2-phenylethanol), and improved poplar growth and development through the production of the phytohormones indole acetic acid, acetoin, and 2,3-butanediol. Metabolite analysis confirmed by quantitative RT–PCR showed that, the production of acetoin and 2,3-butanediol is induced by the presence of sucrose in the growth medium. Interestingly, both the genetic determinants required for sucrose metabolism and the synthesis of acetoin and 2,3-butanediol are clustered on a genomic island. These findings point to a close interaction between Enterobacter sp. 638 and its poplar host, where the availability of sucrose, a major plant sugar, affects the synthesis of plant growth promoting phytohormones by the endophytic bacterium. The availability of the genome sequence, combined with metabolome and transcriptome analysis, will provide a better understanding of the synergistic interactions between poplar and its growth promoting endophyte Enterobacter sp. 638. This information can be further exploited to

  7. 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.

  8. 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

  9. The Role of Plant Growth-Promoting Bacteria in Metal Phytoremediation.

    Science.gov (United States)

    Kong, Zhaoyu; Glick, Bernard R

    2017-01-01

    Phytoremediation is a promising technology that uses plants and their associated microbes to clean up contaminants from the environment. In recent years, phytoremediation assisted by plant growth-promoting bacteria (PGPB) has been highly touted for cleaning up toxic metals from soil. PGPB include rhizospheric bacteria, endophytic bacteria and the bacteria that facilitate phytoremediation by other means. This review provides information about the traits and mechanisms possessed by PGPB that improve plant metal tolerance and growth, and illustrate mechanisms responsible for plant metal accumulation/translocation in plants. Several recent examples of phytoremediation of metals facilitated by PGPB are reviewed. Although many encouraging results have been reported in the past years, there have also been numerous challenges encountered in phytoremediation in the field. To implement PGPB-assisted phytoremediation of metals in the natural environment, there is also a need to critically assess the ecological effects of PGPB, especially for those nonnative bacteria. © 2017 Elsevier Ltd All rights reserved.

  10. Plant growth promoting effect of Bacillus amyloliquefaciens H-2-5 on crop plants and influence on physiological changes in soybean under soil salinity.

    Science.gov (United States)

    Kim, Min-Ji; Radhakrishnan, Ramalingam; Kang, Sang-Mo; You, Young-Hyun; Jeong, Eun-Ju; Kim, Jong-Guk; Lee, In-Jung

    2017-07-01

    This study was aimed to identify plant growth-promoting bacterial isolates from soil samples and to investigate their ability to improve plant growth and salt tolerance by analysing phytohormones production and phosphate solubilisation. Among the four tested bacterial isolates (I-2-1, H-1-4, H-2-3, and H-2-5), H-2-5 was able to enhance the growth of Chinese cabbage, radish, tomato, and mustard plants. The isolated bacterium H-2-5 was identified as Bacillus amyloliquefaciens H-2-5 based on 16S rDNA sequence and phylogenetic analysis. The secretion of gibberellins (GA 4 , GA 8 , GA 9 , GA 19 , and GA 20 ) from B. amyloliquefaciens H-2-5 and their phosphate solubilisation ability may contribute to enhance plant growth. In addition, the H-2-5-mediated mitigation of short term salt stress was tested on soybean plants that were affected by sodium chloride. Abscisic acid (ABA) produced by the H-2-5 bacterium suppressed the NaCl-induced stress effects in soybean by enhancing plant growth and GA 4 content, and by lowering the concentration of ABA, salicylic acid, jasmonic acid, and proline. These results suggest that GAs, ABA production, and the phosphate solubilisation capacity of B. amyloliquefaciens H-2-5 are important stimulators that promote plant growth through their interaction and also to improve plant growth by physiological changes in soybean at saline soil.

  11. On the genetic control of planar growth during tissue morphogenesis in plants.

    Science.gov (United States)

    Enugutti, Balaji; Kirchhelle, Charlotte; Schneitz, Kay

    2013-06-01

    Tissue morphogenesis requires extensive intercellular communication. Plant organs are composites of distinct radial cell layers. A typical layer, such as the epidermis, is propagated by stereotypic anticlinal cell divisions. It is presently unclear what mechanisms coordinate cell divisions relative to the plane of a layer, resulting in planar growth and maintenance of the layer structure. Failure in the regulation of coordinated growth across a tissue may result in spatially restricted abnormal growth and the formation of a tumor-like protrusion. Therefore, one way to approach planar growth control is to look for genetic mutants that exhibit localized tumor-like outgrowths. Interestingly, plants appear to have evolved quite robust genetic mechanisms that govern these aspects of tissue morphogenesis. Here we provide a short summary of the current knowledge about the genetics of tumor formation in plants and relate it to the known control of coordinated cell behavior within a tissue layer. We further portray the integuments of Arabidopsis thaliana as an excellent model system to study the regulation of planar growth. The value of examining this process in integuments was established by the recent identification of the Arabidopsis AGC VIII kinase UNICORN as a novel growth suppressor involved in the regulation of planar growth and the inhibition of localized ectopic growth in integuments and other floral organs. An emerging insight is that misregulation of central determinants of adaxial-abaxial tissue polarity can lead to the formation of spatially restricted multicellular outgrowths in several tissues. Thus, there may exist a link between the mechanisms regulating adaxial-abaxial tissue polarity and planar growth in plants.

  12. Plant Growth Regulators as Potential Tools in Aquatic Plant Management: Efficacy and Persistence in Small-Scale Tests

    Science.gov (United States)

    1994-01-01

    gratefully acknowledge the support of the Waterways Experi- ment Station and Drs. Howard Westerdahl and Kurt Getsinger as this research was being conducted...E. Westerdahl , eds., Plant Growth Regulator Society of America, San Antonio, TX, 127-45. Anderson, L. W. J., and Dechoretz, N. (1988). "Bensulfuron...Vegetation Management. J. E. Kaufman and H. E. Westerdahl , eds., Plant Growth Regulator Society of America, San Antonio, TX, 155-86. Herbicide Handbook

  13. Advancements in Root Growth Measurement Technologies and Observation Capabilities for Container-Grown Plants

    Directory of Open Access Journals (Sweden)

    Lesley A. Judd

    2015-07-01

    Full Text Available The study, characterization, observation, and quantification of plant root growth and root systems (Rhizometrics has been and remains an important area of research in all disciplines of plant science. In the horticultural industry, a large portion of the crops grown annually are grown in pot culture. Root growth is a critical component in overall plant performance during production in containers, and therefore it is important to understand the factors that influence and/or possible enhance it. Quantifying root growth has varied over the last several decades with each method of quantification changing in its reliability of measurement and variation among the results. Methods such as root drawings, pin boards, rhizotrons, and minirhizotrons initiated the aptitude to measure roots with field crops, and have been expanded to container-grown plants. However, many of the published research methods are monotonous and time-consuming. More recently, computer programs have increased in use as technology advances and measuring characteristics of root growth becomes easier. These programs are instrumental in analyzing various root growth characteristics, from root diameter and length of individual roots to branching angle and topological depth of the root architecture. This review delves into the expanding technologies involved with expertly measuring root growth of plants in containers, and the advantages and disadvantages that remain.

  14. Advancements in Root Growth Measurement Technologies and Observation Capabilities for Container-Grown Plants.

    Science.gov (United States)

    Judd, Lesley A; Jackson, Brian E; Fonteno, William C

    2015-07-03

    The study, characterization, observation, and quantification of plant root growth and root systems (Rhizometrics) has been and remains an important area of research in all disciplines of plant science. In the horticultural industry, a large portion of the crops grown annually are grown in pot culture. Root growth is a critical component in overall plant performance during production in containers, and therefore it is important to understand the factors that influence and/or possible enhance it. Quantifying root growth has varied over the last several decades with each method of quantification changing in its reliability of measurement and variation among the results. Methods such as root drawings, pin boards, rhizotrons, and minirhizotrons initiated the aptitude to measure roots with field crops, and have been expanded to container-grown plants. However, many of the published research methods are monotonous and time-consuming. More recently, computer programs have increased in use as technology advances and measuring characteristics of root growth becomes easier. These programs are instrumental in analyzing various root growth characteristics, from root diameter and length of individual roots to branching angle and topological depth of the root architecture. This review delves into the expanding technologies involved with expertly measuring root growth of plants in containers, and the advantages and disadvantages that remain.

  15. Heterocyst placement strategies to maximize the growth of cyanobacterial filaments

    International Nuclear Information System (INIS)

    Brown, Aidan I; Rutenberg, Andrew D

    2012-01-01

    Under conditions of limited fixed-nitrogen, some filamentous cyanobacteria develop a regular pattern of heterocyst cells that fix nitrogen for the remaining vegetative cells. We examine three different heterocyst placement strategies by quantitatively modelling filament growth while varying both external fixed-nitrogen and leakage from the filament. We find that there is an optimum heterocyst frequency which maximizes the growth rate of the filament; the optimum frequency decreases as the external fixed-nitrogen concentration increases but increases as the leakage increases. In the presence of leakage, filaments implementing a local heterocyst placement strategy grow significantly faster than filaments implementing random heterocyst placement strategies. With no extracellular fixed-nitrogen, consistent with recent experimental studies of Anabaena sp. PCC 7120, the modelled heterocyst spacing distribution using our local heterocyst placement strategy is qualitatively similar to experimentally observed patterns. As external fixed-nitrogen is increased, the spacing distribution for our local placement strategy retains the same shape, while the average spacing between heterocysts continuously increases. (paper)

  16. The growth response of plants to elevated CO2 under non-optimal environmental conditions

    NARCIS (Netherlands)

    Poorter, H.; Pérez-Soba, M.

    2001-01-01

    Under benign environmental conditions, plant growth is generally stimulated by elevated atmospheric CO2 concentrations. When environmental conditions become sub- or supra-optimal for growth, changes in the biomass enhancement ratio (BER; total plant biomass at elevated CO2 divided by plant biomass

  17. Effect of crop development on biogenic emissions from plant populations grown in closed plant growth chambers

    Science.gov (United States)

    Batten, J. H.; Stutte, G. W.; Wheeler, R. M.

    1995-01-01

    The Biomass Production Chamber at John F. Kennedy Space Center is a closed plant growth chamber facility that can be used to monitor the level of biogenic emissions from large populations of plants throughout their entire growth cycle. The head space atmosphere of a 26-day-old lettuce (Lactuca sativa cv. Waldmann's Green) stand was repeatedly sampled and emissions identified and quantified using GC-mass spectrometry. Concentrations of dimethyl sulphide, carbon disulphide, alpha-pinene, furan and 2-methylfuran were not significantly different throughout the day; whereas, isoprene showed significant differences in concentration between samples collected in light and dark periods. Volatile organic compounds from the atmosphere of wheat (Triticum aestivum cv. Yecora Rojo) were analysed and quantified from planting to maturity. Volatile plant-derived compounds included 1-butanol, 2-ethyl-1-hexanol, nonanal, benzaldehyde, tetramethylurea, tetramethylthiourea, 2-methylfuran and 3-methylfuran. Concentrations of volatiles were determined during seedling establishment, vegetative growth, anthesis, grain fill and senescence and found to vary depending on the developmental stage. Atmospheric concentrations of benzaldehyde and nonanal were highest during anthesis, 2-methylfuran and 3-methylfuran concentrations were greatest during grain fill, and the concentration of the tetramethylurea peaked during senescence.

  18. Probiotics for Plants? Growth Promotion by the Entomopathogenic Fungus Beauveria bassiana Depends on Nutrient Availability.

    Science.gov (United States)

    Tall, Susanna; Meyling, Nicolai V

    2018-03-28

    Cultivation of crops requires nutrient supplements which are costly and impact the environment. Furthermore, global demands for increased crop production call for sustainable solutions to increase yield and utilize resources such as nutrients more effectively. Some entomopathogenic fungi are able to promote plant growth, but studies over such effects have been conducted under optimal conditions where nutrients are abundantly available. We studied the effects of Beauveria bassiana (strain GHA) seed treatment on the growth of maize (Zea mays) at high and low nutrient conditions during 6 weeks in greenhouse. As expected, B. bassiana seed treatment increased plant growth, but only at high nutrient conditions. In contrast, the seed treatment did not benefit plant growth at low nutrient conditions where the fungus potentially constituted a sink and tended to reduce plant growth. The occurrence of endophytic B. bassiana in experimental plant tissues was evaluated by PCR after 6 weeks, but B. bassiana was not documented in any of the above-ground plant tissues indicating that the fungus-plant interaction was independent of endophytic establishment. Our results suggest that B. bassiana seed treatment could be used as a growth promoter of maize when nutrients are abundantly available, while the fungus does not provide any growth benefits when nutrients are scarce.

  19. Effect of planting density and growing media on growth and yield of strawberry

    International Nuclear Information System (INIS)

    Tariq, R.; Qureshi, K.M.; Hassan, I.; Rasheed, M.; Qureshi, U.S.

    2013-01-01

    Strawberry (Fragaria ananasa), belonging to Rosaceae family, is a rich source of vitamins and minerals with delicate flavors. It is perishable crop which is exceedingly in demand for its taste, profitability, high yield and good quality. To make the plant growth successful in the container, the requirement of special media is very important step because plant growth is largely depended on the physiochemical properties of the growing media used. Winter strawberry production in a greenhouse using high plant densities and various media may be a viable alternative to open-field production system. Planting density can be increased thrice by using different production systems. Studies were conducted to see the impact of different planting densities and media on growth and yield of strawberry. The treatments were T 1 = Control, with normal planting distance of 30 cm x 60 cm and growing media silt, sand and farm yard manure (FYM); T 2 = 15 cm 2 x 30 cm and silt, sand and FYM; T 3 = 30 cm x 60 cm and coir; T 4 = 15 cm x 30 cm and coir; T 5 = 30 cm x 60 cm and peat moss; T 6 = 15 cm x 30 cm and 5 6 peat moss. Results showed that plants grown at low planting distance on all growth media showed more pronounced results as compared to high planting distance. Plants grown in peat moss at both planting densities moderately increased the plant height, canopy size, leaf area, number of fruits, fruit size, fruit weight and titratable acidity. A significant increase in fresh and dry weight of leaves, number of leaves, fruit yield in term of fruit number, fruit size and fruit weight, and fruit quality with high ascorbic acid contents were observed. On the other hand, plants grown in silt, sand and FYM (1 : 1 : 1) at both planting densities showed significant increment in vegetative growth resulting in early flowering with more flowers per plant, better fruit setting and fruit set percentage, greater fruit size and weight but fruit number per plant was reduced which lowered the overall

  20. Nutrient foraging strategies are associated with productivity and population growth in forest shrubs.

    Science.gov (United States)

    Caplan, Joshua S; Stone, Bram W G; Faillace, Cara A; Lafond, Jonathan J; Baumgarten, Joni M; Mozdzer, Thomas J; Dighton, John; Meiners, Scott J; Grabosky, Jason C; Ehrenfeld, Joan G

    2017-04-01

    Temperate deciduous forest understoreys are experiencing widespread changes in community composition, concurrent with increases in rates of nitrogen supply. These shifts in plant abundance may be driven by interspecific differences in nutrient foraging (i.e. conservative vs. acquisitive strategies) and, thus, adaptation to contemporary nutrient loading conditions. This study sought to determine if interspecific differences in nutrient foraging could help explain patterns of shrub success and decline in eastern North American forests. Using plants grown in a common garden, fine root traits associated with nutrient foraging were measured for six shrub species. Traits included the mean and skewness of the root diameter distribution, specific root length (SRL), C:N ratio, root tissue density, arbuscular mycorrhizal colonization and foraging precision. Above- and below-ground productivity were also determined for the same plants, and population growth rates were estimated using data from a long-term study of community dynamics. Root traits were compared among species and associations among root traits, measures of productivity and rates of population growth were evaluated. Species fell into groups having thick or thin root forms, which correspond to conservative vs. acquisitive nutrient foraging strategies. Interspecific variation in root morphology and tissue construction correlated with measures of productivity and rates of cover expansion. Of the four species with acquisitive traits, three were introduced species that have become invasive in recent decades, and the fourth was a weedy native. In contrast, the two species with conservative traits were historically dominant shrubs that have declined in abundance in eastern North American forests. In forest understoreys of eastern North America, elevated nutrient availability may impose a filter on species success in addition to above-ground processes such as herbivory and overstorey canopy conditions. Shrubs that have

  1. The effect of cutting origin and organic plant growth regulator on the growth of Daun Ungu (Graptophyllum pictum) through stem cutting method

    Science.gov (United States)

    Pratama, S. P.; Yunus, A.; Purwanto, E.; Widyastuti, Y.

    2018-03-01

    Graptophyllum pictum is one of medical plants which has important chemical content to treat diseases. Leaf, bark and flower can be used to facilitate menstruation, treat hemorrhoid, constipation, ulcers, ulcers, swelling, and earache. G. pictum is difficult to propagated by seedling due to the long duration of seed formation, thusvegetative propagation is done by stem cutting. The aims of this study are to obtain optimum combination of cutting origin and organic plant growth regulator in various consentration for the growth of Daun Ungu through stem cutting method. This research was conducted at Research center for Medicinal Plant and Traditional DrugTanjungsari, Tegal Gede, Karanganyar in June to August 2016. Origin of cuttings and organic plant growth regulator were used as treatments factor. A completely randomized design (RAL) is used and data were analyzed by F test (ANOVA) with a confidence level of 95%. Any significant differences among treatment followed with Duncan test at a = 5%. The research indicates that longest root was resulted from the treatment of 0,5 ml/l of organic plant growth regulator. The treatment of 1 ml/l is able to increase the fresh and dry weight of root, treatment of 1,5 ml/l of organic plant growth regulator was able to increase the percentage of growing shoots. Treatment of base part as origin of cuttings increases the length, fresh weight and and dry weight of shoot, increase the number of leaves. Interaction treatment between 1 ml/l consentration of organic plant growth regulator and central part origin of cuttings is capable of increasing the leaf area, whereas treatment without organic plant growth regulator and base part as planting material affects the smallest leaf area.

  2. Plant growth enhancing effects by a siderophore-producing endophytic streptomycete isolated from a Thai jasmine rice plant (Oryza sativa L. cv. KDML105).

    Science.gov (United States)

    Rungin, Siriwan; Indananda, Chantra; Suttiviriya, Pavinee; Kruasuwan, Worarat; Jaemsaeng, Ratchaniwan; Thamchaipenet, Arinthip

    2012-10-01

    An endophytic Streptomyces sp. GMKU 3100 isolated from roots of a Thai jasmine rice plant (Oryza sativa L. cv. KDML105) showed the highest siderophore production on CAS agar while phosphate solubilization and IAA production were not detected. A mutant of Streptomyces sp. GMKU 3100 deficient in just one of the plant growth promoting traits, siderophore production, was generated by inactivation of a desD-like gene encoding a key enzyme controlling the final step of siderophore biosynthesis. Pot culture experiments revealed that rice and mungbean plants inoculated with the wild type gave the best enhancement of plant growth and significantly increased root and shoot biomass and lengths compared with untreated controls and siderophore-deficient mutant treatments. Application of the wild type in the presence or absence of ferric citrate significantly promoted plant growth of both plants. The siderophore-deficient mutant clearly showed the effect of this important trait involved in plant-microbe interaction in enhancement of growth in rice and mungbean plants supplied with sequestered iron. Our results highlight the value of a substantial understanding of the relationship of the plant growth promoting properties of endophytic actinomycetes to the plants. Endophytic actinomycetes, therefore, can be applied as potentially safe and environmentally friendly biofertilizers in agriculture.

  3. Growth and phenolic compounds of Lactuca sativa L. grown in a closed-type plant production system with UV-A, -B, or -C lamp.

    Science.gov (United States)

    Lee, Min-Jeong; Son, Jung Eek; Oh, Myung-Min

    2014-01-30

    The production of high-quality crops based on phytochemicals is a strategy for accelerating the practical use of plant factories. Previous studies have demonstrated that ultraviolet (UV) light is effective in improving phytochemical production. This study aimed to determine the effect of various UV wavelengths on growth and phenolic compound accumulation in lettuce (Lactuca sativa L.) grown in a closed-type plant production system. Seven days, 1 day and 0.25 day were determined as the upper limit of the irradiation periods for UV-A, -B, and -C, respectively, in the lettuce based on physiological disorders and the fluorescence parameter F(v)/F(m). Continuous UV-A treatment significantly induced the accumulation of phenolic compounds and antioxidants until 4 days of treatment without growth inhibition, consistent with an increase in phenylalanine ammonia lyase (PAL) gene expression and PAL activity. Repeated or gradual UV-B exposure yielded approximately 1.4-3.6 times more total phenolics and antioxidants, respectively, than the controls did 2 days after the treatments, although both treatments inhibited lettuce growth. Repeated UV-C exposure increased phenolics but severely inhibited the growth of lettuce plants. Our data suggest that UV irradiation can improve the accumulation of phenolic compounds with antioxidant properties in lettuce cultivated in plant factories. © 2013 Society of Chemical Industry.

  4. Study on the Operating Strategy of HVAC Systems for Nuclear Decommissioning Plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung-hwan; Han, Sung-heum; Lee, Jae-gon [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    According as Kori nuclear power plant unit 1 was determined to be defueled in 2017, various studies on nuclear plant decommissioning have been performed. In nuclear decommissioning plant, HVAC systems with large fan and electric coil have to be operated for long periods of time to support various types of work from defueled phase to final dismantling phase. So, in view of safety and utility costs, their overall operating strategy need to be established prior to defueled phase. This study presents HVAC system operating strategy at each decommissioning phase, that is, defueled plant operating phase, SSCs(systems, structures, components) decontamination and dismantling phases. In defueled plant operating phase, all fuel assemblies in reactor vessel are transferred to spent fuel pool(SFP) permanently. In defueled plant operation phase, reduction of the operating system trains is more practicable than the introduction of new HVAC components with reduced capacity. And, based on the result of the accident analyses for this phase, HVAC design bases such as MCR habitability requirement can be mitigated. According to these results, associated SSCs also can be downgraded. In similar approach, at each phase of plant decommissioning, proper inside design conditions and operating strategies should be re-established.

  5. Growth of bean and tomato plants as affected by root absorbed growth substances and atmospheric carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Tognoni, F; Halevy, A H; Wittwer, S H

    1967-01-01

    Bean and tomato plants were grown in solution culture root media containing pre-determined concentrations of gibberellin A/sub 3/ (GA), 1-naphthalene-acetic acid (NAA), N/sup 6/-benzyladenine (BA), (2-chloroethyl)trimethylammonium chloride (CCC), and at atmospheric levels of 300 and 1000 ppm of CO/sub 2/. Net assimilation rates (NAR), relative growth rates (RGR), leaf area ratios (LAR), root to top dry weight ratios (R/T) and changes in dry weight, size, and form of each organ were recorded. Gibberellin had no effect on RGR of either plant species but increased the NAR of tomatoes at 1000 ppm CO/sub 2/. Total dry weight was only slightly affected by GA but root growth and R/T were markedly depressed. CCC had no effect on NAR, but decreased RGR and LAR. Root growth of beans and R/T in both plants were promoted by CCC. NAR and RGR were strongly inhibited by BA and NAA. Inhibition of stem and leaf growth by CCC and NAA was greater than that for roots; thus, R/T ratios were increased. Root branching was promoted by NAA. High (1000 ppm), compared to the low (300 ppm), atmospheric levels of CO/sub 2/ generally promoted root growth and produced an increase in the R/T, both in the absence and presence of chemical treatment. The multiplicity of effects of the root-absorbed chemical growth substances and CO/sub 2/ on growth and photosynthesis is discussed.

  6. Klebsiella pneumoniae inoculants for enhancing plant growth

    Science.gov (United States)

    Triplett, Eric W [Middleton, WI; Kaeppler, Shawn M [Oregon, WI; Chelius, Marisa K [Greeley, CO

    2008-07-01

    A biological inoculant for enhancing the growth of plants is disclosed. The inoculant includes the bacterial strains Herbaspirillum seropedicae 2A, Pantoea agglomerans P101, Pantoea agglomerans P102, Klebsiella pneumoniae 342, Klebsiella pneumoniae zmvsy, Herbaspirillum seropedicae Z152, Gluconacetobacter diazotrophicus PA15, with or without a carrier. The inoculant also includes strains of the bacterium Pantoea agglomerans and K. pneumoniae which are able to enhance the growth of cereal grasses. Also disclosed are the novel bacterial strains Herbaspirillum seropedicae 2A, Pantoea agglomerans P101 and P102, and Klebsiella pneumoniae 342 and zmvsy.

  7. Less is more: strategies to remove marker genes from transgenic plants

    Science.gov (United States)

    2013-01-01

    Selectable marker genes (SMGs) and selection agents are useful tools in the production of transgenic plants by selecting transformed cells from a matrix consisting of mostly untransformed cells. Most SMGs express protein products that confer antibiotic- or herbicide resistance traits, and typically reside in the end product of genetically-modified (GM) plants. The presence of these genes in GM plants, and subsequently in food, feed and the environment, are of concern and subject to special government regulation in many countries. The presence of SMGs in GM plants might also, in some cases, result in a metabolic burden for the host plants. Their use also prevents the re-use of the same SMG when a second transformation scheme is needed to be performed on the transgenic host. In recent years, several strategies have been developed to remove SMGs from GM products while retaining the transgenes of interest. This review describes the existing strategies for SMG removal, including the implementation of site specific recombination systems, TALENs and ZFNs. This review discusses the advantages and disadvantages of existing SMG-removal strategies and explores possible future research directions for SMG removal including emerging technologies for increased precision for genome modification. PMID:23617583

  8. Less is more: strategies to remove marker genes from transgenic plants.

    Science.gov (United States)

    Yau, Yuan-Yeu; Stewart, C Neal

    2013-04-23

    Selectable marker genes (SMGs) and selection agents are useful tools in the production of transgenic plants by selecting transformed cells from a matrix consisting of mostly untransformed cells. Most SMGs express protein products that confer antibiotic- or herbicide resistance traits, and typically reside in the end product of genetically-modified (GM) plants. The presence of these genes in GM plants, and subsequently in food, feed and the environment, are of concern and subject to special government regulation in many countries. The presence of SMGs in GM plants might also, in some cases, result in a metabolic burden for the host plants. Their use also prevents the re-use of the same SMG when a second transformation scheme is needed to be performed on the transgenic host. In recent years, several strategies have been developed to remove SMGs from GM products while retaining the transgenes of interest. This review describes the existing strategies for SMG removal, including the implementation of site specific recombination systems, TALENs and ZFNs. This review discusses the advantages and disadvantages of existing SMG-removal strategies and explores possible future research directions for SMG removal including emerging technologies for increased precision for genome modification.

  9. Plant growth nutrient (nitrobenzene poisoning with multiple complications

    Directory of Open Access Journals (Sweden)

    Yatendra Singh

    2015-01-01

    Full Text Available Nitrobenzene, a pale yellow oily liquid with an odor of bitter almonds, is used in the synthesis of Aniline dyes, flavoring agent, and also in rubber industry. Recently it is also used as a plant growth nutrient. It causes methemoglobinemia with symptoms including headache, nausea, dizziness, fatigue, shortness of breath, cyanosis, and convulsions. Severe acute exposure to nitrobenzene can cause jaundice, renal failure, and coma, and it may be fatal. We report a case of Plant growth nutrient (nitrobenzene poisoning with multiple complications like hemolytic anemia, renal failure, seizures, and pneumonia. Patient was managed with intravenous methylene blue along with other supportive therapy and survived. So, early aggressive management and a watch on complications might be helpful in saving patient′s life from this poisoning.

  10. growth and development of wetland-grown taro under different plant

    African Journals Online (AJOL)

    Administrator

    Each experimental subplot measured 6 m x 6 m and contained 36, 64 and 144 experimental plants, respectively. During a 5-month growth period, leaf area index (LAI) and corm yield were significantly (P 0.05) effect on taro growth and.

  11. Effect of Glomus mosseae and plant growth promoting rhizomicroorganisms (PGPR's on growth, nutrients and content of secondary metabolites in Begonia malabarica Lam.

    Directory of Open Access Journals (Sweden)

    Thangavel Selvaraj

    2008-10-01

    Full Text Available Begonia malabarica Lam. (Begoniaceae is one of the important medicinal plants whose main secondary metabolites are luteolin, quercetin and β-sitosterol. The leaves are used for the treatment of respiratory tract infections, diarrhoea, blood cancer and skin diseases. A study was undertaken to determine the effect of arbuscular mycorrhizal (AM fungus, Glomus mosseae, and some plant growth promoting rhizomicro-organisms (PGPR's on the growth, biomass, nutrients, and content of secondary metabolites of B. malabarica plant under green house conditions. Various plant growth parameters (total plant biomass, mycorrhizal parameter, shoot and root phosphorus, mineral content (potassium, iron, zinc, and copper, and secondary metabolites (total phenols, ortho-dihydroxy phenols, tannins, flavonoids, and alkaloids were determined and found to vary with different treatments. Among all the treatments, plants inoculated with 'microbial consortium' consisting of Glomus mosseae + Bacillus coagulans + Trichoderma viride performed better than with other treatments or uninoculated control plants. The results of this experiment clearly indicated that inoculation of B. malabarica with G. mosseae along with PGPR's enhanced its growth, biomass yield, nutrients and secondary metabolites.

  12. Effects of inoculation of plant growth-promoting rhizobacteria on metal uptake by Brassica juncea

    International Nuclear Information System (INIS)

    Wu, S.C.; Cheung, K.C.; Luo, Y.M.; Wong, M.H.

    2006-01-01

    A greenhouse study was carried out with Brassica juncea to critically evaluate effects of bacterial inoculation on the uptake of heavy metals from Pb-Zn mine tailings by plants. Application of plant growth-promoting rhizobacteria, including nitrogen-fixing bacteria and phosphate and potassium solubilizers, might play an important role in the further development of phytoremediation techniques. The presence of these beneficial bacteria stimulated plant growth and protected the plant from metal toxicity. Inoculation with rhizobacteria had little influence on the metal concentrations in plant tissues, but produced a much larger above-ground biomass and altered metal bioavailability in the soil. As a consequence, higher efficiency of phytoextraction was obtained compared with control treatments. - Rhizobacteria promoted growth above normal biomass, but did not influence plant metal concentrations

  13. Effects of inoculation of plant growth-promoting rhizobacteria on metal uptake by Brassica juncea

    Energy Technology Data Exchange (ETDEWEB)

    Wu, S.C. [Department of Biology and Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Kowloon Tong, Hong Kong (China); Joint Open Laboratory on Soil and Environment between HKBU and ISSCAS (China); Cheung, K.C. [Department of Biology and Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Kowloon Tong, Hong Kong (China); Joint Open Laboratory on Soil and Environment between HKBU and ISSCAS (China); Luo, Y.M. [Institute of Soil Science, Chinese Academy of Sciences, Nanjing (China); Joint Open Laboratory on Soil and Environment between HKBU and ISSCAS (China); Wong, M.H. [Department of Biology and Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Kowloon Tong, Hong Kong (China) and Joint Open Laboratory on Soil and Environment between HKBU and ISSCAS (China)]. E-mail: mhwong@hkbu.edu.hk

    2006-03-15

    A greenhouse study was carried out with Brassica juncea to critically evaluate effects of bacterial inoculation on the uptake of heavy metals from Pb-Zn mine tailings by plants. Application of plant growth-promoting rhizobacteria, including nitrogen-fixing bacteria and phosphate and potassium solubilizers, might play an important role in the further development of phytoremediation techniques. The presence of these beneficial bacteria stimulated plant growth and protected the plant from metal toxicity. Inoculation with rhizobacteria had little influence on the metal concentrations in plant tissues, but produced a much larger above-ground biomass and altered metal bioavailability in the soil. As a consequence, higher efficiency of phytoextraction was obtained compared with control treatments. - Rhizobacteria promoted growth above normal biomass, but did not influence plant metal concentrations.

  14. Stimulation of the growth of Jatropha curcas by the plant growth promoting bacterium Enterobacter cancerogenus MSA2.

    Science.gov (United States)

    Jha, Chaitanya Kumar; Patel, Baldev; Saraf, Meenu

    2012-03-01

    A novel Enterobacter cancerogenus MSA2 is a plant growth promoting gamma-proteobacterium that was isolated from the rhizosphere of Jatropha cucas a potentially important biofuel feed stock plant. Based on phenotypic, physiological, biochemical and phylogenetic studies, strain MSA2 could be classified as a member of E. cancerogenus. However, comparisons of characteristics with other known species of the genus Enterobacter suggested that strain MSA2 could be a novel PGPB strain. In vitro studies were carried for the plant growth promoting attribute of this culture. It tested positive for ACC (1-aminocyclopropane-1-carboxylic acid) deaminase production, phytase, phosphate solubilization, IAA (Indole acetic acid) production, siderophore, and ammonia production. The isolate was then used as a inoculant for the vegetative study of Jatropha curcas plant. Enterobacter cancerogenus MSA2 supplemented with 1% carboxymethylcellulose showed overall plant growth promotion effect resulting in enhanced root length (124.14%), fresh root mass (81%), fresh shoot mass (120.02%), dry root mass (124%), dry shoot mass (105.54%), number of leaf (30.72%), chlorophyll content (50.41%), and biomass (87.20%) over control under the days of experimental observation. This study was designed for 120 days and was in triplicate and the data was collected at every 30 days.

  15. Exact analytic solutions for a global equation of plant cell growth.

    Science.gov (United States)

    Pietruszka, Mariusz

    2010-05-21

    A generalization of the Lockhart equation for plant cell expansion in isotropic case is presented. The goal is to account for the temporal variation in the wall mechanical properties--in this case by making the wall extensibility a time dependent parameter. We introduce a time-differential equation describing the plant growth process with some key biophysical aspects considered. The aim of this work was to improve prior modeling efforts by taking into account the dynamic character of the plant cell wall with characteristics reminiscent of damped (aperiodic) motion. The equations selected to encapsulate the time evolution of the wall extensibility offer a new insight into the control of cell wall expansion. We find that the solutions to the time dependent second order differential equation reproduce much of the known experimental data for long- and short-time scales. Additionally, in order to support the biomechanical approach, a new growth equation based on the action of expansin proteins is proposed. Remarkably, both methods independently converge to the same kind, sigmoid-shaped, growth description functional V(t) proportional, exp(-exp(-t)), properly describing the volumetric growth and, consequently, growth rate as its time derivative. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  16. Engineered chitosan based nanomaterials: Bioactivities, mechanisms and perspectives in plant protection and growth.

    Science.gov (United States)

    Kumaraswamy, R V; Kumari, Sarita; Choudhary, Ram Chandra; Pal, Ajay; Raliya, Ramesh; Biswas, Pratim; Saharan, Vinod

    2018-07-01

    Excessive use of agrochemicals for enhancing crop production and its protection posed environmental and health concern. Integration of advanced technology is required to realize the concept of precision agriculture by minimizing the input of pesticides and fertilizers per unit while improving the crop productivity. Notably, chitosan based biodegradable nanomaterials (NMs) including nanoparticles, nanogels and nanocomposites have eventually proceeded as a key choice in agriculture due to their inimitable properties like antimicrobial and plant growth promoting activities. The foreseeable role of chitosan based NMs in plants might be in achieving sustainable plant growth through boosting the intrinsic potential of plants. In-spite of the fact that chitosan based NMs abode immense biological activities in plants, these materials have not yet been widely adopted in agriculture due to poor understanding of their bioactivity and modes of action towards pathogenic microbes and in plant protection and growth. To expedite the anticipated claims of chitosan based NMs, it is imperative to line up all the possible bioactivities which denote for sustainable agriculture. Herein, we have highlighted, in-depth, various chitosan based NMs which have been used in plant growth and protection mainly against fungi, bacteria and viruses and have also explained their modes of action. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Isolation and biological activity of a new plant growth regulator of Vicia faba L

    International Nuclear Information System (INIS)

    Sembdner, G.; Dathe, W.; Bergner, C.; Roensch, H.

    1983-01-01

    Jasmonic acid was identified as a plant growth inhibitor of the pericarp of Vicia faba by means of gas-liquid chromatography, high resolution mass spectrometry as well as 1 H and 13 C NMR. The highest level of jasmonic acid was reached during intensive pericarp growth. Jasmonic acid is a plant growth inhibitor possessing a relative activity in the wheat seedling bioassay of 1-2.5 % compared to ABA (=100%). Contrary to ABA, jasmonic acid does not cause retardation of leaf emergence. In the dwarf rice gibberellin bioassay relative low concentrations of jasmonic acid inhibit both autonomous and GA 3 -stimulated growth. Jasmonic acid does not influence seed germination of Amaranthus caudatus. The possible physiological role of jasmonic acid in the Vicia pericarp and the distribution in plants of this new plant growth regulator type are discussed. (author)

  18. Isolation and biological activity of a new plant growth regulator of Vicia faba L

    Energy Technology Data Exchange (ETDEWEB)

    Sembdner, G.; Dathe, W.; Bergner, C.; Roensch, H. (Akademie der Wissenschaften der DDR, Halle/Saale. Inst. fuer Biochemie der Pflanzen)

    1983-01-01

    Jasmonic acid was identified as a plant growth inhibitor of the pericarp of Vicia faba by means of gas-liquid chromatography, high resolution mass spectrometry as well as /sup 1/H and /sup 13/C NMR. The highest level of jasmonic acid was reached during intensive pericarp growth. Jasmonic acid is a plant growth inhibitor possessing a relative activity in the wheat seedling bioassay of 1-2.5 % compared to ABA (=100%). Contrary to ABA, jasmonic acid does not cause retardation of leaf emergence. In the dwarf rice gibberellin bioassay relative low concentrations of jasmonic acid inhibit both autonomous and GA/sub 3/-stimulated growth. Jasmonic acid does not influence seed germination of Amaranthus caudatus. The possible physiological role of jasmonic acid in the Vicia pericarp and the distribution in plants of this new plant growth regulator type are discussed.

  19. Getting the ecology into interactions between plants and the plant growth-promoting bacterium Pseudomonas fluorescens.

    Science.gov (United States)

    Hol, W H Gera; Bezemer, T Martijn; Biere, Arjen

    2013-01-01

    Plant growth-promoting rhizobacteria (PGPR) are increasingly appreciated for their contributions to primary productivity through promotion of growth and triggering of induced systemic resistance in plants. Here we focus on the beneficial effects of one particular species of PGPR (Pseudomonas fluorescens) on plants through induced plant defense. This model organism has provided much understanding of the underlying molecular mechanisms of PGPR-induced plant defense. However, this knowledge can only be appreciated at full value once we know to what extent these mechanisms also occur under more realistic, species-diverse conditions as are occurring in the plant rhizosphere. To provide the necessary ecological context, we review the literature to compare the effect of P. fluorescens on induced plant defense when it is present as a single species or in combination with other soil dwelling species. Specifically, we discuss combinations with other plant mutualists (bacterial or fungal), plant pathogens (bacterial or fungal), bacterivores (nematode or protozoa), and decomposers. Synergistic interactions between P. fluorescens and other plant mutualists are much more commonly reported than antagonistic interactions. Recent developments have enabled screenings of P. fluorescens genomes for defense traits and this could help with selection of strains with likely positive interactions on biocontrol. However, studies that examine the effects of multiple herbivores, pathogens, or herbivores and pathogens together on the effectiveness of PGPR to induce plant defenses are underrepresented and we are not aware of any study that has examined interactions between P. fluorescens and bacterivores or decomposers. As co-occurring soil organisms can enhance but also reduce the effectiveness of PGPR, a better understanding of the biotic factors modulating P. fluorescens-plant interactions will improve the effectiveness of introducing P. fluorescens to enhance plant production and defense.

  20. The Contribution of food plants to the growth, development and ...

    African Journals Online (AJOL)

    The Contribution of food plants to the growth, development and fecundity of Zonocerus variegatus (L) ... African Journal of Biotechnology ... The performance of the variegated grasshopper, Zonocerus variegatus (L) fed on different food plants namely cassava (Manihot esculenta), pawpaw (Carica papaya) and acalypha ...

  1. Scaling laws and technology development strategies for biorefineries and bioenergy plants.

    Science.gov (United States)

    Jack, Michael W

    2009-12-01

    The economies of scale of larger biorefineries or bioenergy plants compete with the diseconomies of scale of transporting geographically distributed biomass to a central location. This results in an optimum plant size that depends on the scaling parameters of the two contributions. This is a fundamental aspect of biorefineries and bioenergy plants and has important consequences for technology development as "bigger is better" is not necessarily true. In this paper we explore the consequences of these scaling effects via a simplified model of biomass transportation and plant costs. Analysis of this model suggests that there is a need for much more sophisticated technology development strategies to exploit the consequences of these scaling effects. We suggest three potential strategies in terms of the scaling parameters of the system.

  2. Sphagnum growth in floating cultures: Effect of planting design

    Directory of Open Access Journals (Sweden)

    Y. Hoshi

    2017-11-01

    Full Text Available To establish rapid and stable Sphagnum growth, capitulum culture of a selected strain of S. palustre was carried out using a floating culture method. Four planting treatments were tested at mountain and urban sites in Kumamoto Prefecture on Kyushu Island, south-west Japan. Capitula were planted in colonies of different sizes on 30 cm square floating rafts, but with strict control of the number (75–77 of capitula per raft. The initial cover of live green Sphagnum ranged from 15 to 20 %. Growth of the colonies was followed throughout the growing season (April to November of 2008. After three months, green coverage rates reached 40–50 % in all planting treatments. At the end of the growing season, the highest Sphagnum cover (almost 90 % at the urban site was recorded in the planting treatment with eleven re-introduced colonies of seven capitula (‘11×7cap’, while the highest capitulum number and biomass (dry weight gain occurred in the ‘4×19cap’ planting treatment. Average stem elongation ranged from 5 cm to 7 cm in the ‘77×1cap’ and ‘4×19cap’planting treatments, respectively, indicating that the larger sized colony grew longer stems. However, contrary to expectation, the ‘4×19cap’planting treatment - which had the largest colony size - did not deliver the highest number of newly formed side shoots.

  3. Effect of sea salt irrigation on plant growth, yield potential and some biochemical attributes of carissa carandas

    International Nuclear Information System (INIS)

    Tayyab, A.

    2016-01-01

    Carissa carandas (varn. Karonda) is an edible and medicinal plant having ability to grow in saline and water deficit conditions, however, little is known about its salinity tolerance. Therefore, the effect of salinity on vegetative (height and volume), reproductive (number of flowers and number, size and weight of fruits) and some biochemical parameters (leaf pigments, ions, soluble sugars, proteins, and phenols) of C. carandas were studied. Plants were grown in drum pot culture and irrigated with non-saline or saline water of 0.6% and 0.8% sea salt concentrations, for a period of 30 months. Results showed that, plant height, and canopy volume decreased with increasing salinity. The chlorophyll contents and chlorophyll a/b ratio followed the similar trend as for growth, however, carotenoids increased at 0.6% sea salt and subsequently decreased in higher salinity. Unchanged soluble sugar and protein content at 0.6% sea salt, as compared to control, could be attributed to leaf osmotic adjustments which decreased with further increase in salinity. Linear increase in soluble phenols and carotenoid/chlorophyll ratio indicating a protective strategy of C. carandas to minimize photo-damage. Besides increasing Na+ and decreasing K+ contents, plant seemed to maintain K+/Na+ ratio (above 1), especially at 0.6 sea salt, which disturbed at higher salinity. Salinity adversely affected reproductive growth of C. carandas where, production of flowers, and fruits were significantly reduced. In addition, fresh and dry weights of fruits decreased with increasing salinity, but salinity did not affect fruit length and diameter. Present study provides basic information related to plant growth, fruit yield and some biochemical attributes, which suggest that C. carandas is moderately salt tolerant plant. This plant showed potential to grow on saline marginal lands using brackish water irrigation and provide biomass for edible and medicinal purposes. However, in-depth analysis of field and

  4. Invasion strategies in clonal aquatic plants: are phenotypic differences caused by phenotypic plasticity or local adaptation?

    Science.gov (United States)

    Riis, Tenna; Lambertini, Carla; Olesen, Birgit; Clayton, John S.; Brix, Hans; Sorrell, Brian K.

    2010-01-01

    Background and Aims The successful spread of invasive plants in new environments is often linked to multiple introductions and a diverse gene pool that facilitates local adaptation to variable environmental conditions. For clonal plants, however, phenotypic plasticity may be equally important. Here the primary adaptive strategy in three non-native, clonally reproducing macrophytes (Egeria densa, Elodea canadensis and Lagarosiphon major) in New Zealand freshwaters were examined and an attempt was made to link observed differences in plant morphology to local variation in habitat conditions. Methods Field populations with a large phenotypic variety were sampled in a range of lakes and streams with different chemical and physical properties. The phenotypic plasticity of the species before and after cultivation was studied in a common garden growth experiment, and the genetic diversity of these same populations was also quantified. Key Results For all three species, greater variation in plant characteristics was found before they were grown in standardized conditions. Moreover, field populations displayed remarkably little genetic variation and there was little interaction between habitat conditions and plant morphological characteristics. Conclusions The results indicate that at the current stage of spread into New Zealand, the primary adaptive strategy of these three invasive macrophytes is phenotypic plasticity. However, while limited, the possibility that genetic diversity between populations may facilitate ecotypic differentiation in the future cannot be excluded. These results thus indicate that invasive clonal aquatic plants adapt to new introduced areas by phenotypic plasticity. Inorganic carbon, nitrogen and phosphorous were important in controlling plant size of E. canadensis and L. major, but no other relationships between plant characteristics and habitat conditions were apparent. This implies that within-species differences in plant size can be explained

  5. Maize yield and quality in response to plant density and application of a novel plant growth regulator

    NARCIS (Netherlands)

    Zhang, Q.; Zhang, L.; Evers, J.B.; Werf, van der W.; Zhang, W.; Duan, L.

    2014-01-01

    Farmers in China have gradually increased plant density in maize to achieve higher yields, but this has increased risk of lodging due to taller and weaker stems at higher plant densities. Plant growth regulators can be used to reduce lodging risk. In this study, for the first time, the performance

  6. Seedling growth strategies in Bauhinia species: comparing lianas and trees

    NARCIS (Netherlands)

    Cai, Z.Q.; Poorter, L.; Cao, K.F.; Bongers, F.J.J.M.

    2007-01-01

    Background and Aims: Lianas are expected to differ from trees in their growth strategies. As a result these two groups of woody species will have different spatial distributions: lianas are more common in high light environments. This study determines the differences in growth patterns, biomass

  7. Pockets of opportunity: multicultural marketing strategies for BEP growth.

    Science.gov (United States)

    Schaefer, Kelly

    2003-01-01

    Ranked among the 50 largest food service corporations in America, the Randolph-Sheppard Business Enterprise Program (BEP) represents a challenging and rewarding career opportunity for Americans who are legally blind. In recent years, however, the number of facilities and facility managers has declined. Multicultural consumers represent a major emerging growth market. The multicultural market is one of the most overlooked retail markets in the United States--and the one with the most buying power and growth potential. Multicultural marketing is among the least understood strategies available to facility managers, vocational rehabilitation counselors and BEP directors. Four major minority markets are discussed and marketing strategies are offered to help BEPs target and serve these unique consumers.

  8. TCP Transcription Factors at the Interface between Environmental Challenges and the Plant's Growth Responses.

    Science.gov (United States)

    Danisman, Selahattin

    2016-01-01

    Plants are sessile and as such their reactions to environmental challenges differ from those of mobile organisms. Many adaptions involve growth responses and hence, growth regulation is one of the most crucial biological processes for plant survival and fitness. The plant-specific TEOSINTE BRANCHED 1, CYCLOIDEA, PCF1 (TCP) transcription factor family is involved in plant development from cradle to grave, i.e., from seed germination throughout vegetative development until the formation of flowers and fruits. TCP transcription factors have an evolutionary conserved role as regulators in a variety of plant species, including orchids, tomatoes, peas, poplar, cotton, rice and the model plant Arabidopsis. Early TCP research focused on the regulatory functions of TCPs in the development of diverse organs via the cell cycle. Later research uncovered that TCP transcription factors are not static developmental regulators but crucial growth regulators that translate diverse endogenous and environmental signals into growth responses best fitted to ensure plant fitness and health. I will recapitulate the research on TCPs in this review focusing on two topics: the discovery of TCPs and the elucidation of their evolutionarily conserved roles across the plant kingdom, and the variety of signals, both endogenous (circadian clock, plant hormones) and environmental (pathogens, light, nutrients), TCPs respond to in the course of their developmental roles.

  9. Phytohormone profiles induced by Trichoderma isolates correspond with their biocontrol and plant growth-promoting activity on melon plants

    NARCIS (Netherlands)

    Martínez-Medina, Ainhoa; Del Mar Alguacil, Maria; Pascual, Jose A.; van Wees, Saskia C M|info:eu-repo/dai/nl/185445373

    2014-01-01

    The application of Trichoderma strains with biocontrol and plant growth-promoting capacities to plant substrates can help reduce the input of chemical pesticides and fertilizers in agriculture. Some Trichoderma isolates can directly affect plant pathogens, but they also are known to influence the

  10. Plant growth improvement mediated by nitrate capture in co-composted biochar

    Science.gov (United States)

    Kammann, Claudia I.; Schmidt, Hans-Peter; Messerschmidt, Nicole; Linsel, Sebastian; Steffens, Diedrich; Müller, Christoph; Koyro, Hans-Werner; Conte, Pellegrino; Stephen, Joseph

    2015-01-01

    Soil amendment with pyrogenic carbon (biochar) is discussed as strategy to improve soil fertility to enable economic plus environmental benefits. In temperate soils, however, the use of pure biochar mostly has moderately-negative to -positive yield effects. Here we demonstrate that co-composting considerably promoted biochars’ positive effects, largely by nitrate (nutrient) capture and delivery. In a full-factorial growth study with Chenopodium quinoa, biomass yield increased up to 305% in a sandy-poor soil amended with 2% (w/w) co-composted biochar (BCcomp). Conversely, addition of 2% (w/w) untreated biochar (BCpure) decreased the biomass to 60% of the control. Growth-promoting (BCcomp) as well as growth-reducing (BCpure) effects were more pronounced at lower nutrient-supply levels. Electro-ultra filtration and sequential biochar-particle washing revealed that co-composted biochar was nutrient-enriched, particularly with the anions nitrate and phosphate. The captured nitrate in BCcomp was (1) only partly detectable with standard methods, (2) largely protected against leaching, (3) partly plant-available, and (4) did not stimulate N2O emissions. We hypothesize that surface ageing plus non-conventional ion-water bonding in micro- and nano-pores promoted nitrate capture in biochar particles. Amending (N-rich) bio-waste with biochar may enhance its agronomic value and reduce nutrient losses from bio-wastes and agricultural soils. PMID:26057083

  11. Plant growth improvement mediated by nitrate capture in co-composted biochar

    Science.gov (United States)

    Kammann, Claudia I.; Schmidt, Hans-Peter; Messerschmidt, Nicole; Linsel, Sebastian; Steffens, Diedrich; Müller, Christoph; Koyro, Hans-Werner; Conte, Pellegrino; Stephen, Joseph

    2015-06-01

    Soil amendment with pyrogenic carbon (biochar) is discussed as strategy to improve soil fertility to enable economic plus environmental benefits. In temperate soils, however, the use of pure biochar mostly has moderately-negative to -positive yield effects. Here we demonstrate that co-composting considerably promoted biochars’ positive effects, largely by nitrate (nutrient) capture and delivery. In a full-factorial growth study with Chenopodium quinoa, biomass yield increased up to 305% in a sandy-poor soil amended with 2% (w/w) co-composted biochar (BCcomp). Conversely, addition of 2% (w/w) untreated biochar (BCpure) decreased the biomass to 60% of the control. Growth-promoting (BCcomp) as well as growth-reducing (BCpure) effects were more pronounced at lower nutrient-supply levels. Electro-ultra filtration and sequential biochar-particle washing revealed that co-composted biochar was nutrient-enriched, particularly with the anions nitrate and phosphate. The captured nitrate in BCcomp was (1) only partly detectable with standard methods, (2) largely protected against leaching, (3) partly plant-available, and (4) did not stimulate N2O emissions. We hypothesize that surface ageing plus non-conventional ion-water bonding in micro- and nano-pores promoted nitrate capture in biochar particles. Amending (N-rich) bio-waste with biochar may enhance its agronomic value and reduce nutrient losses from bio-wastes and agricultural soils.

  12. Long term effects on petrochemical activated sludge on plants and soil. Plant growth and metal absorption

    Energy Technology Data Exchange (ETDEWEB)

    Tedesco, M J; Gianello, C [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Dept. de Solos; Ribas, P I.F.; Carvalho, E B [CORSAN-SITEL, Triunfo, RS (Brazil). Polo Petroquimico do Sul. Dept. de Operacao e Manutencao

    1994-12-31

    An experiment to study the effects of several application rates of excess activated sludge on plants, soil and leached water was started in 1985. Sludge was applied for six years and increased plant growth due to its nitrogen and phosphorous contribution, even though the decomposition rate in soil is low. Plant zinc, cadmium and nickel content increased with sludge application, while liming decreased the amounts of these metals taken up by plants. 9 refs., 8 tabs.

  13. Long term effects on petrochemical activated sludge on plants and soil. Plant growth and metal absorption

    Energy Technology Data Exchange (ETDEWEB)

    Tedesco, M.J.; Gianello, C. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Dept. de Solos; Ribas, P.I.F.; Carvalho, E.B. [CORSAN-SITEL, Triunfo, RS (Brazil). Polo Petroquimico do Sul. Dept. de Operacao e Manutencao

    1993-12-31

    An experiment to study the effects of several application rates of excess activated sludge on plants, soil and leached water was started in 1985. Sludge was applied for six years and increased plant growth due to its nitrogen and phosphorous contribution, even though the decomposition rate in soil is low. Plant zinc, cadmium and nickel content increased with sludge application, while liming decreased the amounts of these metals taken up by plants. 9 refs., 8 tabs.

  14. Harzianolide, a novel plant growth regulator and systemic resistance elicitor from Trichoderma harzianum.

    Science.gov (United States)

    Cai, Feng; Yu, Guanghui; Wang, Ping; Wei, Zhong; Fu, Lin; Shen, Qirong; Chen, Wei

    2013-12-01

    A detailed understanding of the effect of natural products on plant growth and protection will underpin new product development for plant production. The isolation and characterization of a known secondary metabolite named harzianolide from Trichoderma harzianum strain SQR-T037 were described, and the bioactivity of the purified compound as well as the crude metabolite extract in plant growth promotion and systemic resistance induction was investigated in this study. The results showed that harzianolide significantly promoted tomato seedling growth by up to 2.5-fold (dry weight) at a concentration of 0.1 ppm compared with the control. The result of root scan suggested that Trichoderma secondary metabolites may influence the early stages of plant growth through better root development for the enhancement of root length and tips. Both of the purified harzianolide and crude metabolite extract increased the activity of some defense-related enzymes to response to oxidative stress. Examination of six defense-related gene expression by real-time reverse transcription-PCR analysis revealed that harzianolide induces the expression of genes involved in the salicylic acid (PR1 and GLU) and jasmonate/ethylene (JERF3) signaling pathways while crude metabolite extract inhibited some gene expression (CHI-II and PGIP) related to basal defense in tomato plants. Further experiment showed that a subsequent challenge of harzianolide-pretreated plants with the pathogen Sclerotinia sclerotiorum resulted in higher systemic resistance by the reduction of lesion size. These results indicate that secondary metabolites of Trichoderma spp., like harzianolide, may play a novel role in both plant growth regulation and plant defense responses. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  15. Laser effects on the growth and photosynthesis process in mustard plants (Sinapis Alba)

    Science.gov (United States)

    Anghel, Sorin; Stanescu, Constantin S.; Giosanu, Dana; Flenacu, Monica; Iorga-Siman, Ion

    2001-06-01

    In this paper we present the results of our experiments concerning the influence of the low energy laser (LEL) radiation on the germination, growth and photosyntheses processes in mustard plants (sinapis alba). We used a He-Ne laser ((lambda) equals 632.8 nm, P equals 6 mW) to irradiate the mustard seeds with different exposure times. The seeds were sowed and some determinations (the germination and growth intensity, chlorophyll quantity, and respiration intensity) were made on the plant culture. We ascertained that the germination and growth of the plants are influenced by the irradiation. Also, the chlorophyll quantity is the same for both plants from irradiated and non-irradiated seeds but the respiration and photosynthesis processes are influenced by the irradiation.

  16. Value as a parameter to consider in operational strategies for CSP plants

    Science.gov (United States)

    de Meyer, Oelof; Dinter, Frank; Govender, Saneshan

    2017-06-01

    This paper introduced a value parameter to consider when analyzing operational strategies for CSP plants. The electric system in South Africa, used as case study, is severely constrained with an influx of renewables in the early phase of deployment. The energy demand curve for the system is analyzed showing the total wind and solar photovoltaic contributions for winter and summer. Due to the intermittent nature and meteorological operating conditions of wind and solar photovoltaic plants, the value of CSP plants within the electric system is introduced. Analyzing CSP plants based on the value parameter alone will remain only a philosophical view. Currently there is no quantifiable measure to translate the philosophical view or subjective value and it solely remains the position of the stakeholder. By introducing three other parameters, Cost, Plant and System to a holistic representation of the Operating Strategies of generation plants, the Value parameter can be translated into a quantifiable measure. Utilizing the country's current procurement program as case study, CSP operating under the various PPA within the Bid Windows are analyzed. The Value Cost Plant System diagram developed is used to quantify the value parameter. This paper concluded that no value is obtained from CSP plants operating under the Bid Window 1 & 2 Power Purchase Agreement. However, by recognizing the dispatchability potential of CSP plants in Bid Window 3 & 3.5, the value of CSP in the electric system can be quantified utilizing Value Added Relationship VCPS-diagram. Similarly ancillary services to the system were analyzed. One of the relationships that have not yet been explored within the industry is an interdependent relationship. It was emphasized that the cost and value structure is shared between the plant and system. Although this relationship is functional when the plant and system belongs to the same entity, additional value is achieved by marginalizing the cost structure. A

  17. Hydro-economic performances of streamflow withdrawal strategies: the case of small run-of-river power plants

    Science.gov (United States)

    Basso, Stefano; Lazzaro, Gianluca; Schirmer, Mario; Botter, Gianluca

    2014-05-01

    River flows withdrawals to supply small run-of-river hydropower plants have been increasing significantly in recent years - particularly in the Alpine area - as a consequence of public incentives aimed at enhancing energy production from renewable sources. This growth further raised the anthropic pressure in areas traditionally characterized by an intense exploitation of water resources, thereby triggering social conflicts among local communities, hydropower investors and public authorities. This brought to the attention of scientists and population the urgency for novel and quantitative tools for assessing the hydrologic impact of these type of plants, and trading between economic interests and ecologic concerns. In this contribution we propose an analytical framework that allows for the estimate of the streamflow availability for hydropower production and the selection of the run-of-river plant capacity, as well as the assessment of the related profitability and environmental impacts. The method highlights the key role of the streamflow variability in the design process, by showing the significance control of the coefficient of variation of daily flows on the duration of the optimal capacity of small run-of-river plants. Moreover, the analysis evidences a gap between energy and economic optimizations, which may result in the under-exploitation of the available hydropower potential at large scales. The disturbances to the natural flow regime produced between the intake and the outflow of run-of-river power plants are also estimated within the proposed framework. The altered hydrologic regime, described through the probability distribution and the correlation function of streamflows, is analytically expressed as a function of the natural regime for different management strategies. The deviations from pristine conditions of a set of hydrologic statistics are used, jointly with an economic index, to compare environmental and economic outcomes of alternative plant

  18. Root-induced decomposer growth and plant N uptake are not positively associated among a set of grassland plants

    DEFF Research Database (Denmark)

    Saj, S.; Mikola, J.; Ekelund, Flemming

    2008-01-01

    It is known that plant species can induce development of different soil decomposer communities and that they differ in their influence on organic matter decomposition and N mineralization in soil. However, no study has so far assessed whether these two observations are related to each other. Base...... that plant traits such as competitive ability for soil mineral N were more important for plant uptake of litter-N than those that directly affected the growth of soil decomposers.......It is known that plant species can induce development of different soil decomposer communities and that they differ in their influence on organic matter decomposition and N mineralization in soil. However, no study has so far assessed whether these two observations are related to each other. Based...... on the hypothesis that root-induced growth of soil decomposers leads to accelerated decomposition of SOM and increased plant N availability in soil, we predicted that (1) among a set of grassland plants the abundance of soil decomposers in the plant rhizosphere is positively associated with plant N uptake from soil...

  19. Effect of plant growth hormones and abiotic stresses on germination ...

    African Journals Online (AJOL)

    Phosphatases are widely found in plants having intracellular and extracellular activities. Phosphatases are believed to be important for phosphorous scavenging and remobilization in plants, but its role in adaptation to abiotic stresses and growth hormones at germination level has not been critically evaluated. To address ...

  20. Plant Density Effect in Different Planting Dates on Growth Indices, Yield and

    Directory of Open Access Journals (Sweden)

    F Azizi

    2013-04-01

    Full Text Available In order to determine the appropriate plant density in different planting dates for sweet corn cultivar KSC403su, an experiment was conducted using a randomized complete block design in split plot lay out with three replications at Seed and Plant Improvement Institute in Karaj in 2006. Three planting dates (22 May, 5 June and 22 June were assigned as main plots and three plant densities (65000, 75000 and 85000 plants per hectare were considered as sub plots. Effect of planting date on row/ear, 1000 kernels weight, biological yield and harvest index was significant at 1% probability level and it was significant at 5% probability level for kernels/ear row and grain yield. All traits decreased with postponement of planting date to 5 June except for row/ear, kernels/row and grain yield. More delay in planting from 22 May to 22 June caused that grain yield was decreased significantly about 32.5% (from 14.45 to 9.78 ton/ha. Effect of plant density was significant at 1% probability level for all the traits. All of the traits decreased significantly with increasing plant density except for biological yield. The highest grain yield was resulted from 65000 plants per hectare density (14.20 ton/ha. Interaction effect of planting date and plant density was significant at 5% probability level for biological yield and harvest index but it wasn’t significant for the other traits. Growth indices decreased with delay in planting date and increasing plant density. Only leaf area index increased in more plant densities. From the results of this experiment it might be resulted that appropriate planting date to produce the highest grain yield is 22 May to 5 June for sweet corn cultivar KSC403su and also the highest grain yield can obtain from 65000 plants per hectare density.

  1. Diversity and Plant Growth Promoting Properties of Rhizobacteria ...

    African Journals Online (AJOL)

    characteristics of plant growth promoting rhizobacteria (PGPR) and hence selected for further study. The sixty ... tolerance to a wide range of pH by most of the isolates. The 66 isolates ... chemicals and change in traditional cultivation practices ...

  2. Time interval between cover crop termination and planting influences corn seedling disease, plant growth, and yield

    Science.gov (United States)

    Experiments were established in controlled and field environment to evaluate the effect of time intervals between cereal rye cover crop termination and corn planting on corn seedling disease, corn growth, and grain yield in 2014 and 2015. Rye termination dates ranged from 25 days before planting (DB...

  3. 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)

  4. 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.

  5. Tomato progeny inherit resistance to the nematode Meloidogyne javanica linked to plant growth induced by the biocontrol fungus Trichoderma atroviride.

    Science.gov (United States)

    Medeiros, Hugo Agripino de; Araújo Filho, Jerônimo Vieira de; Freitas, Leandro Grassi de; Castillo, Pablo; Rubio, María Belén; Hermosa, Rosa; Monte, Enrique

    2017-01-10

    Root-knot nematodes (RKN) are major crop pathogens worldwide. Trichoderma genus fungi are recognized biocontrol agents and a direct activity of Trichoderma atroviride (Ta) against the RKN Meloidogyne javanica (Mj), in terms of 42% reduction of number of galls (NG), 60% of number of egg masses and 90% of number of adult nematodes inside the roots, has been observed in tomato grown under greenhouse conditions. An in vivo split-root designed experiment served to demonstrate that Ta induces systemic resistance towards Mj, without the need for the organisms to be in direct contact, and significantly reduces NG (20%) and adult nematodes inside tomato roots (87%). The first generation (F1) of Ta-primed tomato plants inherited resistance to RKN; although, the induction of defenses occurred through different mechanisms, and in varying degrees, depending on the Ta-Mj interaction. Plant growth promotion induced by Ta was inherited without compromising the level of resistance to Mj, as the progeny of Ta-primed plants displayed increased size and resistance to Mj without fitness costs. Gene expression results from the defense inductions in the offspring of Ta-primed plants, suggested that an auxin-induced reactive oxygen species production promoted by Ta may act as a major defense strategy during plant growth.

  6. Feed intake, growth performance and digestibility in goats fed whole corn plant silage and Napier grass

    Directory of Open Access Journals (Sweden)

    Khaing, K.T.

    2015-06-01

    Full Text Available Shortage and inconsistent quality of forage in developing countries are the major constraints to the development of ruminant sector. To overcome these problems, feeding of ruminants with conserved forages is an important feeding strategy to ensure the success of ruminant production in the third world countries. The use of whole corn plant as silage has drawn many attention due to high protein efficiency, relatively high digestible energy and total digestible nutrients. Thus, the objective of this study was to determine feed intake, growth performance and nutrients digestibility in goats fed different inclusion level of whole corn plant silage to Napier grass based diets. Fifteen male Boer cross goats around six months old and approximately 18.54 ? 1.83 kg of body weight were used as experimental animals. The goats were assigned into five treatment groups consisted of different proportions of Napier grass (G and whole plant corn silage (CS ?T1:100/0 G/CS; T2:75/25 G/CS; T3:50/50 G/CS; T4:25/75 G/CS and T5:0/100 G/CS. The increase of corn silage to Napier grass proportion demonstrates increase in dry matter intake and growth performance in the goats. The highest nutrient digestibility was observed in T5:0/100 G/CS and T3:50/50 G/CS. It can be concluded that high proportion of corn silage to grass diets had resulted in increases in feed intake and growth performance of goats. Feeding the animals with T5 and T3 resulted in high nutrient utilization compared to other treatments. However, the highest growth performance was observed in animals that were fed with T5 diets.

  7. Biochar and flyash inoculated with plant growth promoting rhizobacteria act as potential biofertilizer for luxuriant growth and yield of tomato plant.

    Science.gov (United States)

    Tripti; Kumar, Adarsh; Usmani, Zeba; Kumar, Vipin; Anshumali

    2017-04-01

    Overuse of agrochemical fertilizers alarmingly causes deterioration in soil health and soil-flora. Persistence of these agrochemicals exerts detrimental effects on environment, potentially inducing toxic effects on human health, thus pronouncing an urgent need for a safer substitute. The present study investigates the potential use of agricultural and industrial wastes as carrier materials, viz. biochar and flyash, respectively, for preparation of bioformulations (or biofertilizers) using two plant growth promoting rhizobacteria, Bacillus sp. strain A30 and Burkholderia sp. strain L2, and its effect on growth of Lycopersicon esculentum Mill. (tomato). The viability of strains was determined based on colony forming units (cfu) count of each bioformulation at an interval of 60 days for a period of 240 days. Seeds were coated with different carrier based bioformulations and pot experiment(s) were carried out to access its effects on plant growth parameters. Biochar based bioformulations showed higher cfu count and maximum viability for strain L2 (10 7  cfu g -1 ) at 240 days of storage. Maximum percentage of seed germination was also observed in biochar inoculated with strain L2. Significant (p < 0.05) increase in plant growth parameters (dry and fresh biomass, length, number of flowers) were ascertained from the pot experiment and amongst all bioformulations, biochar inoculated with strain L2 performed consistently thriving results for tomato yield. Furthermore, post-harvest study of this bioformulation treated soil improved physico-chemical properties and dehydrogenase activity as compared to pre-plantation soil status. Overall, we show that prepared biochar based bioformulation using Burkholderia sp. L2 as inoculum can tremendously enhance the productivity of tomato, soil fertility, and can also act as a sustainable substitute for chemical fertilizers. In addition, mixture of biochar and flyash inoculated with strain L2 also showed noteworthy results for the

  8. Bacillus pumilus ES4: candidate plant growth-promoting bacterium to enhance establishment of plants in mine tailings

    Science.gov (United States)

    de-Bashan, Luz E.; Hernandez, Juan-Pablo; Bashan, Yoav; Maier, Raina

    2014-01-01

    Three plant growth-promoting bacteria (PGPB; Bacillus pumilus ES4, B. pumilus RIZO1, and Azospirillum brasilense Cd) were tested for their ability to enhance plant growth and development of the native Sonoran Desert shrub quailbush (Atriplex lentiformis) and for their effect on the native bacterial community in moderately acidic, high-metal content (AHMT) and in neutral, low metal content natural tailings (NLMT) in controlled greenhouse experiments. Inoculation of quailbush with all three PGPB significantly enhanced plant growth parameters, such as germination, root length, dry weight of shoots and roots, and root/shoot ratio in both types of tailings. The effect of inoculation on the indigenous bacterial community by the most successful PGPB Bacillus pumilus ES4 was evaluated by denaturating gradient gel electrophoresis (PCR-DGGE) fingerprinting and root colonization was followed by specific fluorescent in situ hybridization (FISH). Inoculation with this strain significantly changed the bacterial community over a period of 60 days. FISH analysis showed that the preferred site of colonization was the root tips and root elongation area. This study shows that inoculation of native perennial plants with PGPB can be used for developing technologies for phytostabilizing mine tailings. PMID:25009362

  9. Spatial Regulation of Root Growth: Placing the Plant TOR Pathway in a Developmental Perspective

    Science.gov (United States)

    Barrada, Adam; Montané, Marie-Hélène; Robaglia, Christophe; Menand, Benoît

    2015-01-01

    Plant cells contain specialized structures, such as a cell wall and a large vacuole, which play a major role in cell growth. Roots follow an organized pattern of development, making them the organs of choice for studying the spatio-temporal regulation of cell proliferation and growth in plants. During root growth, cells originate from the initials surrounding the quiescent center, proliferate in the division zone of the meristem, and then increase in length in the elongation zone, reaching their final size and differentiation stage in the mature zone. Phytohormones, especially auxins and cytokinins, control the dynamic balance between cell division and differentiation and therefore organ size. Plant growth is also regulated by metabolites and nutrients, such as the sugars produced by photosynthesis or nitrate assimilated from the soil. Recent literature has shown that the conserved eukaryotic TOR (target of rapamycin) kinase pathway plays an important role in orchestrating plant growth. We will summarize how the regulation of cell proliferation and cell expansion by phytohormones are at the heart of root growth and then discuss recent data indicating that the TOR pathway integrates hormonal and nutritive signals to orchestrate root growth. PMID:26295391

  10. Woodfuel procurement strategies of district heating plants

    International Nuclear Information System (INIS)

    Roos, A.; Bohlin, F.; Hektor, B.; Hillring, B.

    2003-01-01

    Woodfuel use in the Swedish district heating sector increased significantly from 1985 to 1999. This study analysed strategies and considerations concerning woodfuel procurement in district heating plants. Priorities and concerns in the industry involved an increased woodfuel share, ambitions to create an environmental image, cost minimisation, awareness about the role of energy policies for fuel choice, improvement of woodfuel quality and the ambition to maintain a competitive woodfuel market with several suppliers. Factor analysis yielded five dimensions in the woodfuel procurement strategies among the district heating companies: (1) increased woodfuel use; (2) import; (3) spot market woodfuel purchases; (4) focus on refined woodfuels; and (5) using price only when deciding whether to use woodfuels or other fuels. Five clusters were defined along the three strategy dimensions (1)-(3). The clusters differed concerning size, experiences from the introduction of woodfuels, perceptions about woodfuels and strategies employed to date. This paper describes different strategies that the district heating companies apply on the woodfuel market. The conclusion is that policies should consider this diversity in procurement strategies, mitigate their negative side-effects and assist to make them cost-effective. (author)

  11. Effect of plant growth regulators on regeneration of the endangered ...

    African Journals Online (AJOL)

    Development of an efficient in vitro regeneration protocol of Calligonum comosum is important and that has achieved to protect the endangered multipurpose medicinally important desert plant in the Kingdom of Bahrain. Nodal segments were used as explants source and the effect of various plant growth regulators (PGRs) ...

  12. Less favourable climates constrain demographic strategies in plants

    DEFF Research Database (Denmark)

    Csergo, Anna M.; Salguero-Gomez, Roberto; Broennimann, Olivier

    2017-01-01

    , little comparative empirical support exists for a relationship between predicted climate suitability and population performance. We found that the performance of 93 populations of 34 plant species worldwide – as measured by in situ population growth rate, its temporal variation and extinction risk...

  13. Plant Growth Enhancement, Disease Resistance, and Elemental Modulatory Effects of Plant Probiotic Endophytic Bacillus sp. Fcl1.

    Science.gov (United States)

    Jayakumar, Aswathy; Krishna, Arathy; Mohan, Mahesh; Nair, Indu C; Radhakrishnan, E K

    2018-04-13

    Endophytic bacteria have already been studied for their beneficial support to plants to manage both biotic and abiotic stress through an array of well-established mechanisms. They have either direct or indirect impact on mobilizing diverse nutrients and elements from soil to plants. However, detailed insight into the fine-tuning of plant elemental composition by associated microorganism is very limited. In this study, endophytic Bacillus Fcl1 characterized from the rhizome of Curcuma longa was found to have broad range of plant growth-promoting and biocontrol mechanisms. The organism was found to have indole acetic acid and 1-aminocyclopropane-1-carboxylate deaminase production properties along with nitrogen fixation. The Bacillus Fcl1 could also inhibit diverse phytopathogens as confirmed by dual culture and well diffusion. By LC-MS/MS analysis, chemical basis of its antifungal activity has been proved to be due to the production of iturin A and a blend of surfactin compounds. Moreover, the organism was found to induce both plant growth and disease resistance in vivo in model plant system. Because of these experimentally demonstrated multiple plant probiotic features, Bacillus Fcl1 was selected as a candidate organism to study its role in modulation of plant elemental composition. ICP-MS analysis of Bacillus Fcl1-treated plants provided insight into relation of bacterial interaction with elemental composition of plants.

  14. Application of poultry processing industry waste: a strategy for vegetation growth in degraded soil.

    Science.gov (United States)

    do Nascimento, Carla Danielle Vasconcelos; Pontes Filho, Roberto Albuquerque; Artur, Adriana Guirado; Costa, Mirian Cristina Gomes

    2015-02-01

    The disposal of poultry processing industry waste into the environment without proper care, can cause contamination. Agricultural monitored application is an alternative for disposal, considering its high amount of organic matter and its potential as a soil fertilizer. This study aimed to evaluate the potential of poultry processing industry waste to improve the conditions of a degraded soil from a desertification hotspot, contributing to leguminous tree seedlings growth. The study was carried out under greenhouse conditions in a randomized blocks design and a 4 × 2 factorial scheme with five replicates. The treatments featured four amounts of poultry processing industry waste (D1 = control 0 kg ha(-1); D2 = 1020.41 kg ha(-1); D3 = 2040.82 kg ha(-1); D4 = 4081.63 kg ha(-1)) and two leguminous tree species (Mimosa caesalpiniaefolia Benth and Leucaena leucocephala (Lam.) de Wit). The poultry processing industry waste was composed of poultry blood, grease, excrements and substances from the digestive system. Plant height, biomass production, plant nutrient accumulation and soil organic carbon were measured forty days after waste application. Leguminous tree seedlings growth was increased by waste amounts, especially M. caesalpiniaefolia Benth, with height increment of 29.5 cm for the waste amount of 1625 kg ha(-1), and L. leucocephala (Lam.) de Wit, with maximum height increment of 20 cm for the waste amount of 3814.3 kg ha(-1). M. caesalpiniaefolia Benth had greater initial growth, as well as greater biomass and nutrient accumulation compared with L. leucocephala (Lam.) de Wit. However, belowground biomass was similar between the evaluated species, resulting in higher root/shoot ratio for L. leucocephala (Lam.) de Wit. Soil organic carbon did not show significant response to waste amounts, but it did to leguminous tree seedlings growth, especially L. leucocephala (Lam.) de Wit. Poultry processing industry waste contributes to leguminous tree seedlings growth

  15. Fenton process-affected transformation of roxarsone in paddy rice soils: Effects on plant growth and arsenic accumulation in rice grain.

    Science.gov (United States)

    Qin, Junhao; Li, Huashou; Lin, Chuxia

    2016-08-01

    Batch and greenhouse experiments were conducted to examine the effects of Fenton process on transformation of roxarsone in soils and its resulting impacts on the growth of and As uptake by a rice plant cultivar. The results show that addition of Fenton reagent markedly accelerated the degradation of roxarsone and produced arsenite, which was otherwise absent in the soil without added Fenton reagent. Methylation of arsenate was also enhanced by Fenton process in the earlier part of the experiment due to abundant supply of arsenate from Roxarsone degradation. Overall, addition of Fenton reagent resulted in the predominant presence of arsenate in the soils. Fenton process significantly improved the growth of rice in the maturity stage of the first crop, The concentration of methylated As species in the rice plant tissues among the different growth stages was highly variable. Addition of Fenton reagent into the soils led to reduced uptake of soil-borne As by the rice plants and this had a significant effect on reducing the accumulation of As in rice grains. The findings have implications for understanding As biogeochemistry in paddy rice field receiving rainwater-borne H2O2 and for development of mitigation strategies to reduce accumulation of As in rice grains. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Plant growth inhibition by soluble salts in sewage sludge-amended mine spoils

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, C.S.; Anderson, R.C. [Illinois State University, Normal, IL (United States). Dept. of Biological Sciences

    1995-07-01

    The growth response of prairie switchgrass {ital Panicum virgatum}L was compared in strip mine spoil amended with various levels of anaerobically digested waste-activated sewage sludge (0, 56, 111, 222, or 333 dry Mg ha{sup -1}) and commercial fertilizer, pure sludge, and glasshouse soil. Plants were grown in a growth chamber and substrates were maintained at field capacity during the study. Soluble salt concentrations of the substrates increased linearly as a function of sludge amendment and were within the range known to inhibit the growth of many plant species at the high levels of sludge application. There was, however, a linear response of biomass production to increasing levels of sludge amendment. Maintaining substrates at field capacity apparently prevented the high concentration of soluble salts from inhibiting plant growth. The increased biomass yield associated with sludge application was likely due to the increased availability of inorganic nutrients associated with sludge amendment. 22 refs., 2 figs., 2 tabs.

  17. Ecosystem-scale plant hydraulic strategies inferred from remotely-sensed soil moisture

    Science.gov (United States)

    Bassiouni, M.; Good, S. P.; Higgins, C. W.

    2017-12-01

    Characterizing plant hydraulic strategies at the ecosystem scale is important to improve estimates of evapotranspiration and to understand ecosystem productivity and resilience. However, quantifying plant hydraulic traits beyond the species level is a challenge. The probability density function of soil moisture observations provides key information about the soil moisture states at which evapotranspiration is reduced by water stress. Here, an inverse Bayesian approach is applied to a standard bucket model of soil column hydrology forced with stochastic precipitation inputs. Through this approach, we are able to determine the soil moisture thresholds at which stomata are open or closed that are most consistent with observed soil moisture probability density functions. This research utilizes remotely-sensed soil moisture data to explore global patterns of ecosystem-scale plant hydraulic strategies. Results are complementary to literature values of measured hydraulic traits of various species in different climates and previous estimates of ecosystem-scale plant isohydricity. The presented approach provides a novel relation between plant physiological behavior and soil-water dynamics.

  18. The effect of plant growth regulators, explants and cultivars on ...

    African Journals Online (AJOL)

    ONOS

    2010-07-05

    Jul 5, 2010 ... The effect of plant growth regulators, explants and cultivars on spinach (Spinacia oleracea L.) tissue culture. Taha Roodbar Shojaei1*, Vahid Salari2, Darioush Ramazan3, Mahdi Ehyaei1, Javad. Gharechahi4 and Roya Motallebi Chaleshtori5. 1Department of Agronomy and Plant Breeding, College of ...

  19. Improvement of the growth and yield of lettuce plants by elf sinusoidal non-uniform magnetic fields

    International Nuclear Information System (INIS)

    Souzal, A. De; Gonzalez, L.M.; Sueirol, L.; Peralta, O.; Liceal, L.; Porras, E.; Gilart, F.

    2008-01-01

    Influence of pre-sowing magnetic treatments on plant growth and final yield of lettuce (cv. Black Seeded Simpson) were studied under organoponic conditions. Lettuce seeds were exposed to full-wave rectified sinusoidal non-uniform magnetic fields (MFs) induced by an electromagnet at 120 mT(rms) for 3 min, 160 mT(rms) for 1 min and to 160 mT (rms) for 5 min. Non-treated seeds were considered as controls. Plants were grown in experimental stonemasons (25.2 m2) of an organoponic and cultivated according to standard agricultural practices. During nursery and vegetative growth stages, samples were collected at regular intervals for seedling growth assessment and growth rate analyses. At physiological maturity, the plants were harvested from each stonemason and the final yield and yield parameters were determined. In the nursery stage, the magnetic treatments induced a significant increase of root length and shoot height in plants derived from magnetically-treated seeds. In the vegetative stage, the relative growth rates of plants derived from magnetically-exposed seeds were greater than those shown by the control plants. At maturity stage, all magnetic treatments increased significantly (p<0.05) the plant height, the leaf area per plant, the final yield per area and the fresh mass per plant in comparison with the controls. Pre-sowing magnetic treatments would enhance the growth and final yield of lettuce crop

  20. Plant Growth-Promoting Microorganisms for Environmental Sustainability.

    Science.gov (United States)

    Abhilash, P C; Dubey, Rama Kant; Tripathi, Vishal; Gupta, Vijai K; Singh, Harikesh B

    2016-11-01

    Agrochemicals used to meet the needs of a rapidly growing human population can deteriorate the quality of ecosystems and are not affordable to farmers in low-resource environments. Here, we propose the use of plant growth-promoting microorganisms (PGPMs) as a tool for sustainable food production without compromising ecosystems services. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Comparison of signaling interactions determining annual and perennial plant growth in response to low temperature

    Directory of Open Access Journals (Sweden)

    Astrid eWingler

    2015-01-01

    Full Text Available Low temperature inhibits plant growth despite the fact that considerable rates of photosynthetic activity can be maintained. Instead of lower rates of photosynthesis, active inhibition of cell division and expansion is primarily responsible for reduced growth. This results in sink limitation and enables plants to accumulate carbohydrates that act as compatible solutes or are stored throughout the winter to enable re-growth in spring. Regulation of growth in response to temperature therefore requires coordination with carbon metabolism, e.g. via the signaling metabolite trehalose-6-phosphate. The phytohormones gibberellins (GA and jasmonate (JA play an important role in regulating growth in response to temperature. Growth restriction at low temperature is mainly mediated by DELLA proteins, whose degradation is promoted by GA. For annual plants, it has been shown that the GA/DELLA pathway interacts with JA signaling and C-repeat binding factor (CBF dependent cold acclimation, but these interactions have not been explored in detail for perennials. Growth regulation in response to seasonal factors is, however, particularly important in perennials, especially at high latitudes. In autumn, growth cessation in trees is caused by shortening of the daylength in interaction with phytohormone signaling. In perennial grasses seasonal differences in the sensitivity to GA may enable enhanced growth in spring. This review provides an overview of the signaling interactions that determine plant growth at low temperature and highlights gaps in our knowledge, especially concerning the seasonality of signaling responses in perennial plants.

  2. Role of ethylene and related gene expression in the interaction between strawberry plants and the plant growth-promoting bacterium Azospirillum brasilense.

    Science.gov (United States)

    Elías, J M; Guerrero-Molina, M F; Martínez-Zamora, M G; Díaz-Ricci, J C; Pedraza, R O

    2018-05-01

    Induced systemic resistance (ISR) is one of the indirect mechanisms of growth promotion exerted by plant growth-promoting bacteria, and can be mediated by ethylene (ET). We assessed ET production and the expression of related genes in the Azospirillum-strawberry plant interaction. Ethylene production was evaluated by gas chromatography in plants inoculated or not with A. brasilense REC3. Also, plants were treated with AgNO 3 , an inhibitor of ET biosynthesis; with 1-aminocyclopropane-1-carboxylic acid (ACC), a precursor of ET biosynthesis; and with indole acetic acid (IAA). Plant dry biomass and the growth index were determined to assess the growth-promoting effect of A. brasilense REC3 in strawberry plants. Quantitative real time PCR (qRT-PCR) was performed to analyse relative expression of the genes Faetr1, Faers1 and Faein4, which encode ET receptors; Factr1 and Faein2, involved in the ET signalling pathway; Faacs1 encoding ACC synthase; Faaco1 encoding ACC oxidase; and Faaux1 and Faami1 for IAA synthesis enzymes. Results showed that ET acts as a rapid and transient signal in the first 12 h post-treatment. A. brasilense REC3-inoculated plants had a significantly higher growth index compared to control plants. Modulation of the genes Faetr1, Faers1, Faein4, Factr1, Faein2 and Faaco1 indicated activation of ET synthesis and signalling pathways. The up-regulation of Faaux1 and Faami1 involved in IAA synthesis suggested that inoculation with A. brasilense REC3 induces production of this auxin, modulating ET signalling. Ethylene production and up-regulation of genes associated with ET signalling in strawberry plants inoculated with A. brasilense REC3 support the priming activation characteristic of ISR. This type of resistance and the activation of systemic acquired resistance previously observed in this interaction indicate that both are present in strawberry plants, could act synergistically and increase protection against pathogens. © 2018 German Society

  3. Complete genome analysis of Serratia marcescens RSC-14: A plant growth-promoting bacterium that alleviates cadmium stress in host plants

    Science.gov (United States)

    Khan, Abdur Rahim; Park, Gun-Seok; Asaf, Sajjad; Hong, Sung-Jun; Jung, Byung Kwon

    2017-01-01

    Serratia marcescens RSC-14 is a Gram-negative bacterium that was previously isolated from the surface-sterilized roots of the Cd-hyperaccumulator Solanum nigrum. The strain stimulates plant growth and alleviates Cd stress in host plants. To investigate the genetic basis for these traits, the complete genome of RSC-14 was obtained by single-molecule real-time sequencing. The genome of S. marcescens RSC-14 comprised a 5.12-Mbp-long circular chromosome containing 4,593 predicted protein-coding genes, 22 rRNA genes, 88 tRNA genes, and 41 pseudogenes. It contained genes with potential functions in plant growth promotion, including genes involved in indole-3-acetic acid (IAA) biosynthesis, acetoin synthesis, and phosphate solubilization. Moreover, annotation using NCBI and Rapid Annotation using Subsystem Technology identified several genes that encode antioxidant enzymes as well as genes involved in antioxidant production, supporting the observed resistance towards heavy metals, such as Cd. The presence of IAA pathway-related genes and oxidative stress-responsive enzyme genes may explain the plant growth-promoting potential and Cd tolerance, respectively. This is the first report of a complete genome sequence of Cd-tolerant S. marcescens and its plant growth promotion pathway. The whole-genome analysis of this strain clarified the genetic basis underlying its phenotypic and biochemical characteristics, underpinning the beneficial interactions between RSC-14 and plants. PMID:28187139

  4. Pectin Methylesterification Impacts the Relationship between Photosynthesis and Plant Growth1[OPEN

    Science.gov (United States)

    Kim, Sang-Jin; Renna, Luciana; Brandizzi, Federica

    2016-01-01

    Photosynthesis occurs in mesophyll cells of specialized organs such as leaves. The rigid cell wall encapsulating photosynthetic cells controls the expansion and distribution of cells within photosynthetic tissues. The relationship between photosynthesis and plant growth is affected by leaf area. However, the underlying genetic mechanisms affecting carbon partitioning to different aspects of leaf growth are not known. To fill this gap, we analyzed Arabidopsis plants with altered levels of pectin methylesterification, which is known to modulate cell wall plasticity and plant growth. Pectin methylesterification levels were varied through manipulation of cotton Golgi-related (CGR) 2 or 3 genes encoding two functionally redundant pectin methyltransferases. Increased levels of methylesterification in a line over-expressing CGR2 (CGR2OX) resulted in highly expanded leaves with enhanced intercellular air spaces; reduced methylesterification in a mutant lacking both CGR-genes 2 and 3 (cgr2/3) resulted in thin but dense leaf mesophyll that limited CO2 diffusion to chloroplasts. Leaf, root, and plant dry weight were enhanced in CGR2OX but decreased in cgr2/3. Differences in growth between wild type and the CGR-mutants can be explained by carbon partitioning but not by variations in area-based photosynthesis. Therefore, photosynthesis drives growth through alterations in carbon partitioning to new leaf area growth and leaf mass per unit leaf area; however, CGR-mediated pectin methylesterification acts as a primary factor in this relationship through modulation of the expansion and positioning of the cells in leaves, which in turn drive carbon partitioning by generating dynamic carbon demands in leaf area growth and leaf mass per unit leaf area. PMID:27208234

  5. In vitro antagonistic activity, plant growth promoting traits and phylogenetic affiliation of rhizobacteria associated with wild plants grown in arid soil

    OpenAIRE

    El-Sayed, Wael S.; Akhkha, Abdellah; El-Naggar, Moustafa Y.; Elbadry, Medhat

    2014-01-01

    The role of plant growth-promoting rhizobacteria (PGPR) in adaptation of plants in extreme environments is not yet completely understood. For this study native bacteria were isolated from rhizospeheric arid soils and evaluated for both growth-promoting abilities and antagonistic potential against phytopathogenic fungi and nematodes. The phylogentic affiliation of these representative isolates was also characterized. Rhizobacteria associated with 11 wild plant species from the arid soil of Alm...

  6. In vitro antifungal activities of 26 plant extracts on mycelial growth of ...

    African Journals Online (AJOL)

    Antifungal activities of 26 plant extracts were tested against Phytophthora infestans using radial growth technique. While all tested plant extracts produced some antifungal activities Xanthium strumarium, Lauris nobilis, Salvia officinalis and Styrax officinalis were the most active plants that showed potent antifungal activity.

  7. Growth responses of maritime sand dune plant species to arbuscular mycorrhizal fungi

    Directory of Open Access Journals (Sweden)

    Mariusz Tadych

    2014-08-01

    Full Text Available In a pot experiment conducted in a greenhouse, the response of 6 plant species dominating in the succession of vegetation of a deflation hollow of the Łeba Bar to inoculation with arbuscular mycorrhizal fungi (AMF was investigated. The inoculum was a mixture of soil, roots and spores of 5 species of AMF with the dominant species Glomus aggregatum. Except for Corynephorus canescens and Festuca rubra subsp. arenaria, both the growth and the dry matter of above-ground parts of plants of Agrostis stolonifera, Ammophila arenaria, Corynephorus canescens, Juncus articulatus and J. balticus inoculated with AMF were higher than those growing in soils lacking infection propagules of these fungi. Inoculation with AMF decreased the dry matter of root: shoot ratios in 5 plant species. This property was not determined in Festuca rubra subsp. arenaria due to the death of all control plants. The level of mycorrhizal infection was low and did not correlate with the growth responses found. The high growth reaction of Juncus spp. to AMF found in this study suggests that the opinion of non-mycotrophy or low dependence of plants of Juncaceae on AMF was based on results of investigations of plants growing in wet sites known to inhibit the formation of mycorrhizae.

  8. Stripping Away the Soil: Plant Growth Promoting Microbiology Opportunities in Aquaponics

    Directory of Open Access Journals (Sweden)

    Ryan P. Bartelme

    2018-01-01

    Full Text Available As the processes facilitated by plant growth promoting microorganisms (PGPMs become better characterized, it is evident that PGPMs may be critical for successful sustainable agricultural practices. Microbes enrich plant growth through various mechanisms, such as enhancing resistance to disease and drought, producing beneficial molecules, and supplying nutrients and trace metals to the plant rhizosphere. Previous studies of PGPMs have focused primarily on soil-based crops. In contrast, aquaponics is a water-based agricultural system, in which production relies upon internal nutrient recycling to co-cultivate plants with fish. This arrangement has management benefits compared to soil-based agriculture, as system components may be designed to directly harness microbial processes that make nutrients bioavailable to plants in downstream components. However, aquaponic systems also present unique management challenges. Microbes may compete with plants for certain micronutrients, such as iron, which makes exogenous supplementation necessary, adding production cost and process complexity, and limiting profitability and system sustainability. Research on PGPMs in aquaponic systems currently lags behind traditional agricultural systems, however, it is clear that certain parallels in nutrient use and plant-microbe interactions are retained from soil-based agricultural systems.

  9. Stripping Away the Soil: Plant Growth Promoting Microbiology Opportunities in Aquaponics.

    Science.gov (United States)

    Bartelme, Ryan P; Oyserman, Ben O; Blom, Jesse E; Sepulveda-Villet, Osvaldo J; Newton, Ryan J

    2018-01-01

    As the processes facilitated by plant growth promoting microorganisms (PGPMs) become better characterized, it is evident that PGPMs may be critical for successful sustainable agricultural practices. Microbes enrich plant growth through various mechanisms, such as enhancing resistance to disease and drought, producing beneficial molecules, and supplying nutrients and trace metals to the plant rhizosphere. Previous studies of PGPMs have focused primarily on soil-based crops. In contrast, aquaponics is a water-based agricultural system, in which production relies upon internal nutrient recycling to co-cultivate plants with fish. This arrangement has management benefits compared to soil-based agriculture, as system components may be designed to directly harness microbial processes that make nutrients bioavailable to plants in downstream components. However, aquaponic systems also present unique management challenges. Microbes may compete with plants for certain micronutrients, such as iron, which makes exogenous supplementation necessary, adding production cost and process complexity, and limiting profitability and system sustainability. Research on PGPMs in aquaponic systems currently lags behind traditional agricultural systems, however, it is clear that certain parallels in nutrient use and plant-microbe interactions are retained from soil-based agricultural systems.

  10. Application of Multivariable Statistical Techniques in Plant-wide WWTP Control Strategies Analysis

    DEFF Research Database (Denmark)

    Flores Alsina, Xavier; Comas, J.; Rodríguez-Roda, I.

    2007-01-01

    The main objective of this paper is to present the application of selected multivariable statistical techniques in plant-wide wastewater treatment plant (WWTP) control strategies analysis. In this study, cluster analysis (CA), principal component analysis/factor analysis (PCA/FA) and discriminant...... analysis (DA) are applied to the evaluation matrix data set obtained by simulation of several control strategies applied to the plant-wide IWA Benchmark Simulation Model No 2 (BSM2). These techniques allow i) to determine natural groups or clusters of control strategies with a similar behaviour, ii......) to find and interpret hidden, complex and casual relation features in the data set and iii) to identify important discriminant variables within the groups found by the cluster analysis. This study illustrates the usefulness of multivariable statistical techniques for both analysis and interpretation...

  11. The correlation between plant growth and intercepted radiation: an interpretation in terms of optimal plant nitrogen content

    International Nuclear Information System (INIS)

    Dewar, R.C.

    1996-01-01

    Photosynthesis of leaves is commonly observed to have a saturating response to increases in their nitrogen (N) content, while the response of plant maintenance respiration is more nearly linear over the normal range of tissue N contents. Hence, for a given amount of foliage, net primary productivity (NPP) may have a maximum value with respect to variations in plant N content. Using a simple analytically-solvable model of NPP, this idea is formulated and its broad implications for plant growth are explored at the scale of a closed stand of vegetation. The maximum-NPP hypothesis implies that NPP is proportional to intercepted radiation, as commonly observed. The light utilization coefficient (ε), defined as the slope of this relationship, is predicted to be ε = αY g (1−λ) 2 , where α is the quantum yield, Y g is the biosynthetic efficiency, and λ is a dimensionless combination of physiological and environmental parameters of the model. The maximum-NPP hypothesis is also consistent with observations that whole-plant respiration (R) is an approximately constant proportion of gross canopy photosynthesis (A c ), and predicts their ratio to be R:A c = 1−Y g (1−λ). Using realistic parameter values, predicted values for ε and R:A c are typical of C 3 plants. ε is predicted to be independent of plant N supply, consistent with observations that long-term growth responses to N fertilization are dominated by increased light interception associated with increased growth allocation to leaf area. Observed acclimated responses of plants to atmospheric [CO 2 ], light and temperature are interpreted in terms of the model. (author)

  12. Analytical Role of Corporate Strategy in Growth and Expansion of Unilever Pakistan

    Directory of Open Access Journals (Sweden)

    Hassan Abbas

    2018-03-01

    Full Text Available The corporate strategy plays an integral role in providing business entities with a market direction. The formulation and implementation of corporate strategy aids in providing businesses with abilities and capabilities so as to maintain and develop adequate pace with the consistently changing business environment, aids in the development of a strategic vision and focus on overall business goals and objectives, strengthens decision making and most importantly helps in the provision of a competitive edge to a business. The role of corporate strategy becomes highly significant when the business operates globally. The research undertakes the relative role, significance and overall impact of its corporate strategy in making adequate contribution towards the attainment of business growth and expansion and assessing the correlation between the corporate strategy and overall business growth.

  13. Impacts of Plant Growth-Promoting Rhizobacteria-based Biostimulants on Wheat Growth under Greenhouse and Field Conditions

    OpenAIRE

    Nguyen, Minh; Ongena, Marc; Colinet, Gilles; Vandenbol, Micheline; Spaepen, Stijn; Bodson, Bernard; Jijakli, Haissam; du Jardin, Patrick; Delaplace, Pierre

    2015-01-01

    Plant Growth-Promoting Rhizobacteria (PGPR) are one of the main biostimulant classes due to their capacity of stimulating root growth and enhancing soil mineral availability, hence increasing nutrient use efficiency in crops. The aim of this study is to screen commercially PGPR-containing products to enhance wheat growth and yield in combination with an optimized nitrogen (N) fertilizer application scheme. This could lead to a significant reduction of N fertilizer application without affectin...

  14. Soilless plant growth media influence the efficacy of phytohormones and phytohormone inhibitors.

    Science.gov (United States)

    Best, Norman B; Hartwig, Thomas; Budka, Joshua S; Bishop, Brandon J; Brown, Elliot; Potluri, Devi P V; Cooper, Bruce R; Premachandra, Gnanasiri S; Johnston, Cliff T; Schulz, Burkhard

    2014-01-01

    Plant growth regulators, such as hormones and their respective biosynthesis inhibitors, are effective tools to elucidate the physiological function of phytohormones in plants. A problem of chemical treatments, however, is the potential for interaction of the active compound with the growth media substrate. We studied the interaction and efficacy of propiconazole, a potent and specific inhibitor of brassinosteroid biosynthesis, with common soilless greenhouse growth media for rice, sorghum, and maize. Many of the tested growth media interacted with propiconazole reducing its efficacy up to a hundred fold. To determine the molecular interaction of inhibitors with media substrates, Fourier Transform Infrared Spectroscopy and sorption isotherm analysis was applied. While mica clay substrates absorbed up to 1.3 mg of propiconazole per g substrate, calcined clays bound up to 12 mg of propiconazole per g substrate. The efficacy of the gibberellic acid biosynthesis inhibitor, uniconazole, and the most active brassinosteroid, brassinolide, was impacted similarly by the respective substrates. Conversely, gibberellic acid showed no distinct growth response in different media. Our results suggest that the reduction in efficacy of propiconazole, uniconazole, and brassinolide in bioassays when grown in calcined clay is caused by hydrophobic interactions between the plant growth regulators and the growth media. This was further confirmed by experiments using methanol-water solvent mixes with higher hydrophobicity values, which reduce the interaction of propiconazole and calcined clay.

  15. Methods for growth regulation of greenhouse produced ornamental pot- and bedding plants – a current review

    Directory of Open Access Journals (Sweden)

    Bergstrand Karl-Johan I.

    2017-06-01

    Full Text Available Chemical plant growth regulators (PGRs are used in the production of ornamental potted and bedding plants. Growth control is needed for maximizing production per unit area, reducing transportation costs and to obtain a desired visual quality. However, the use of PGRs is associated with toxicity risks to humans and the environment. In many countries the availability of PGRs is restricted as few substances are registered for use. A number of alternative methods have been suggested. The methods include genetic methods (breeding and crop cultivation practices such as fertigation, temperature and light management. A lot of research into “alternative” growth regulation was performed during the 1980-1990s, revealing several possible ways of using different climatic factors to optimize plant growth with respect to plant height. In recent years, the interest in climatic growth regulation has been resurrected, not least due to the coming phase-out of the plant growth regulator chlormequat chloride (CCC. Today, authorities in many countries are aiming towards reducing the use of agrochemicals. At the same time, there is a strong demand from consumers for products produced without chemicals. This article provides a broad overview of available methods for non-chemical growth control. It is concluded that a combination of plant breeding and management of temperature, fertigation and light management has the potential of replacing chemical growth regulators in the commercial production of ornamental pot- and bedding plants.

  16. Starch accumulation during hydroponic growth of spinach and basil plants under carbon dioxide enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Holbrook, G P; Hansen, J; Wallick, K; Zinnen, T M [North Illinois University, de Kalb, IL (USA). Dept. of Biological Sciences

    1993-04-01

    The effects of CO[sub 2] enrichment, photoperiod duration, and inorganic phosphate levels on growth and starch accumulaton by spinach and basil plants were studied in a commercial hydroponic facility. During a 3-week growth period, both species exhibited increased whole-plant fresh weight as a result of an increase in atmospheric CO[sub 2] concentration from 400 to 1500 mul/1. However, basil leaves exhibited a 1.5- to 2-fold greater increase in specific leaf weight (SLW), and accumulated starch to much greater levels than did leaves of spinach. At 1500 mul CO[sub 2]/1, starch accounted for up to 38% of SLW with basil compared to [lt] 10% of SLW with spinach. The maximum ratio of starch/chlorophyll was 55.0 in basil leaves vs 8.0 in spinach leaves. High ratio values were associated with the appearance of chlorotic symptoms in leaves of basil grown under CO[sub 2] enrichment, whereas spinach did not exhibit chlorosis. Increasing inorganic phosphate concentrations from 0.7 to 1.8 mM in the hydroponic medium did not appreciably affect leaf starch accumulation in either species. Starch accumulation in basil leaves was not consistently related to the duration of the photoperiod. However, photoperiod-induced changes in leaf starch levels were much greater in basil than spinach. The results clearly indicate that different horticultural crops can show diverse responses to CO[sub 2] enrichment, and thus highlight the need to develop individual growth strategies to optimize production quality of each species.

  17. Antifungal activity of plant growth-promoting rhizobacteria isolates ...

    African Journals Online (AJOL)

    Seven plant growth-promoting rhizobacterial (PGPR) strains were isolated from the rhizoplane and rhizosphere of wheat from four different sites of Pakistan. These strains were analyzed for production of indole acetic acid (IAA), phosphorous solublization capability and inhibition of Rhizoctonia solani on rye agar medium.

  18. Business Model Innovation Portfolio Strategy for Growth Under Product-Market Configurations

    OpenAIRE

    Bert Verhoeven; Lester W. Johnson

    2017-01-01

    Purpose: The research links three concepts: product market growth strategy, the magnitude of innovation and Business Model Innovation, merging them together into a dynamic Business Model Innovation strategy framework. Design/Methodology/Approach: The paper is conceptual and exploratory in nature and builds on existing literature and the author’s experience with developing business models. Findings: The BMI strategy framework can help managers establish a BMI portfolio strategy followi...

  19. Adaptive diversification of growth allometry in the plant Arabidopsis thaliana.

    Science.gov (United States)

    Vasseur, François; Exposito-Alonso, Moises; Ayala-Garay, Oscar J; Wang, George; Enquist, Brian J; Vile, Denis; Violle, Cyrille; Weigel, Detlef

    2018-03-27

    Seed plants vary tremendously in size and morphology; however, variation and covariation in plant traits may be governed, at least in part, by universal biophysical laws and biological constants. Metabolic scaling theory (MST) posits that whole-organismal metabolism and growth rate are under stabilizing selection that minimizes the scaling of hydrodynamic resistance and maximizes the scaling of resource uptake. This constrains variation in physiological traits and in the rate of biomass accumulation, so that they can be expressed as mathematical functions of plant size with near-constant allometric scaling exponents across species. However, the observed variation in scaling exponents calls into question the evolutionary drivers and the universality of allometric equations. We have measured growth scaling and fitness traits of 451 Arabidopsis thaliana accessions with sequenced genomes. Variation among accessions around the scaling exponent predicted by MST was correlated with relative growth rate, seed production, and stress resistance. Genomic analyses indicate that growth allometry is affected by many genes associated with local climate and abiotic stress response. The gene with the strongest effect, PUB4 , has molecular signatures of balancing selection, suggesting that intraspecific variation in growth scaling is maintained by opposing selection on the trade-off between seed production and abiotic stress resistance. Our findings suggest that variation in allometry contributes to local adaptation to contrasting environments. Our results help reconcile past debates on the origin of allometric scaling in biology and begin to link adaptive variation in allometric scaling to specific genes. Copyright © 2018 the Author(s). Published by PNAS.

  20. Effect of arbuscular mycorrhiza on the growth and development of micropropagated Annona cherimola plants

    Directory of Open Access Journals (Sweden)

    Concepcion Azcón-Aguilar

    1994-05-01

    Full Text Available Annona cherimola Mill., cherimoya, is a tropical plantation crop of interest in fruit culture. Micropropagation techniques have been developed due to the need to increase productivity through clonal selection. Because of the mycorrhizal dependence exhibited by this crop for optimal growth and the recognized role of mycorrhiza establishment for the survival and development of most of the plants produced in vitro, the effect of mycorrhiza inoculation on the development of micropropagated plants of Annona cherimola was investigated. Mycorrhizal inoculation was assayed at two different stages of the micropropagation process: (i immediately after the in vitro phase, before starting the acclimatization period, and (ii after the acclimatization phase, before starting the post-acclimatization period under greenhouse conditions. Plantlet survival was about 50 % after the acclimatization period. Plant growth and development profited remarkably from mycorrhiza establishment. Most of the arbuscular mycorrhizal fungi (AMF assayed greatly increased shoot and root biomass and leaf area. Micropropagated Annona plants seem to be more dependent on mycorrhiza formation for optimal growth than plants derived from seeds. The greatest effects of AMF on plant growth were observed when they were introduced after the acclimatization period.

  1. Differential oxidative and antioxidative response of duckweed Lemna minor toward plant growth promoting/inhibiting bacteria.

    Science.gov (United States)

    Ishizawa, Hidehiro; Kuroda, Masashi; Morikawa, Masaaki; Ike, Michihiko

    2017-09-01

    Bacteria colonizing the plant rhizosphere are believed to positively or negatively affect the host plant productivity. This feature has inspired researchers to engineer such interactions to enhance crop production. However, it remains to be elucidated whether rhizobacteria influences plant oxidative stress vis-a-vis other environmental stressors, and whether such influence is associated with their growth promoting/inhibiting ability. In this study, two plant growth-promoting bacteria (PGPB) and two plant growth-inhibiting bacteria (PGIB) were separately inoculated into axenic duckweed (Lemna minor) culture under laboratory conditions for 4 and 8 days in order to investigate their effects on plant oxidative stress and antioxidant activities. As previously characterized, the inoculation of PGPB and PGIB strains accelerated and reduced the growth of L. minor, respectively. After 4 and 8 days of cultivation, compared to the PGPB strains, the PGIB strains induced larger amounts of O 2 •- , H 2 O 2 , and malondialdehyde (MDA) in duckweed, although all bacterial strains consistently increased O 2 •- content by two times more than that in the aseptic control plants. Activities of five antioxidant enzymes were also elevated by the inoculation of PGIB, confirming the severe oxidative stress condition in plants. These results suggest that the surface attached bacteria affect differently on host oxidative stress and its response, which degree correlates negatively to their effects on plant growth. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  2. Decision-making in plants under competition.

    Science.gov (United States)

    Gruntman, Michal; Groß, Dorothee; Májeková, Maria; Tielbörger, Katja

    2017-12-21

    Plants can plastically respond to light competition in three strategies, comprising vertical growth, which promotes competitive dominance; shade tolerance, which maximises performance under shade; or lateral growth, which offers avoidance of competition. Here, we test the hypothesis that plants can 'choose' between these responses, according to their abilities to competitively overcome their neighbours. We study this hypothesis in the clonal plant Potentilla reptans using an experimental setup that simulates both the height and density of neighbours, thus presenting plants with different light-competition scenarios. Potentilla reptans ramets exhibit the highest vertical growth under simulated short-dense neighbours, highest specific leaf area (leaf area/dry mass) under tall-dense neighbours, and tend to increase total stolon length under tall-sparse neighbours. These responses suggest shifts between 'confrontational' vertical growth, shade tolerance and lateral-avoidance, respectively, and provide evidence that plants adopt one of several alternative plastic responses in a way that optimally corresponds to prevailing light-competition scenarios.

  3. Framework for Creating a Smart Growth Economic Development Strategy

    Science.gov (United States)

    This step-by-step guide can help small and mid-sized cities, particularly those that have limited population growth, areas of disinvestment, and/or a struggling economy, build a place-based economic development strategy.

  4. Phenotypic plasticity of fine root growth increases plant productivity in pine seedlings

    Directory of Open Access Journals (Sweden)

    Grissom James E

    2004-09-01

    Full Text Available Abstract Background The plastic response of fine roots to a changing environment is suggested to affect the growth and form of a plant. Here we show that the plasticity of fine root growth may increase plant productivity based on an experiment using young seedlings (14-week old of loblolly pine. We use two contrasting pine ecotypes, "mesic" and "xeric", to investigate the adaptive significance of such a plastic response. Results The partitioning of biomass to fine roots is observed to reduce with increased nutrient availability. For the "mesic" ecotype, increased stem biomass as a consequence of more nutrients may be primarily due to reduced fine-root biomass partitioning. For the "xeric" ecotype, the favorable influence of the plasticity of fine root growth on stem growth results from increased allocation of biomass to foliage and decreased allocation to fine roots. An evolutionary genetic analysis indicates that the plasticity of fine root growth is inducible, whereas the plasticity of foliage is constitutive. Conclusions Results promise to enhance a fundamental understanding of evolutionary changes of tree architecture under domestication and to design sound silvicultural and breeding measures for improving plant productivity.

  5. Revitalization of plant growth promoting rhizobacteria for sustainable development in agriculture.

    Science.gov (United States)

    Gouda, Sushanto; Kerry, Rout George; Das, Gitishree; Paramithiotis, Spiros; Shin, Han-Seung; Patra, Jayanta Kumar

    2018-01-01

    The progression of life in all forms is not only dependent on agricultural and food security but also on the soil characteristics. The dynamic nature of soil is a direct manifestation of soil microbes, bio-mineralization, and synergistic co-evolution with plants. With the increase in world's population the demand for agriculture yield has increased tremendously and thereby leading to large scale production of chemical fertilizers. Since the use of fertilizers and pesticides in the agricultural fields have caused degradation of soil quality and fertility, thus the expansion of agricultural land with fertile soil is near impossible, hence researchers and scientists have sifted their attention for a safer and productive means of agricultural practices. Plant growth promoting rhizobacteria (PGPR) has been functioning as a co-evolution between plants and microbes showing antagonistic and synergistic interactions with microorganisms and the soil. Microbial revitalization using plant growth promoters had been achieved through direct and indirect approaches like bio-fertilization, invigorating root growth, rhizoremediation, disease resistance etc. Although, there are a wide variety of PGPR and its allies, their role and usages for sustainable agriculture remains controversial and restricted. There is also variability in the performance of PGPR that may be due to various environmental factors that might affect their growth and proliferation in the plants. These gaps and limitations can be addressed through use of modern approaches and techniques such as nano-encapsulation and micro-encapsulation along with exploring multidisciplinary research that combines applications in biotechnology, nanotechnology, agro biotechnology, chemical engineering and material science and bringing together different ecological and functional biological approaches to provide new formulations and opportunities with immense potential. Copyright © 2017 Elsevier GmbH. All rights reserved.

  6. Physiological and proteomic analysis of plant growth enhancement by the rhizobacteria Bacillus sp. JS.

    Science.gov (United States)

    Kim, Ji Seong; Lee, Jeong Eun; Nie, Hualin; Lee, Yong Jae; Kim, Sun Tae; Kim, Sun-Hyung

    2018-02-01

    In this study, the effects of the plant growth-promoting rhizobacterium (PGPR), Bacillus sp. JS on the growth of tobacco (Nicotiana tabacum 'Xanthi') and lettuce (Lactuca sativa 'Crispa'), were evaluated by comparing various growth parameters between plants treated with the bacterium and those exposed to water or nutrient broth as control. In both tobacco and lettuce, fresh weight and length of shoots were increased upon exposure to Bacillus sp. JS. To explain the overall de novo expression of plant proteins by bacterial volatiles, two-dimensional gel electrophoresis was performed on samples from PGPR-treated tobacco plants. Our results showed that chlorophyll a/b binding proteins were significantly up-regulated, and total chlorophyll content was also increased. Our findings indicate the potential benefits of using Bacillus sp. JS as a growth-promoting factor in agricultural practice, and highlight the need for further research to explore these benefits.

  7. Isolation and characterization of plant growth promoting endophytic diazotrophic bacteria from Korean rice cultivars.

    Science.gov (United States)

    Ji, Sang Hye; Gururani, Mayank Anand; Chun, Se-Chul

    2014-01-20

    We have isolated 576 endophytic bacteria from the leaves, stems, and roots of 10 rice cultivars and identified 12 of them as diazotrophic bacteria using a specific primer set of nif gene. Through 16S rDNA sequence analysis, nifH genes were confirmed in the two species of Penibacillus, three species of Microbacterium, three Bacillus species, and four species of Klebsiella. Rice seeds treated with these plant growth-promoting bacteria (PGPB) showed improved plant growth, increased height and dry weight and antagonistic effects against fungal pathogens. In addition, auxin and siderophore producing ability, and phosphate solubilizing activity were studied for the possible mechanisms of plant growth promotion. Among 12 isolates tested, 10 strains have shown higher auxin producing activity, 6 isolates were confirmed as strains with high siderophore producing activity while 4 isolates turned out to have high phosphate-solubilizing activity. These results strongly suggest that the endophytic diazotrophic bacteria characterized in this study could be successfully used to promote plant growth and inducing fungal resistance in plants. Copyright © 2013 Elsevier GmbH. All rights reserved.

  8. Trajectories and models of individual growth

    Directory of Open Access Journals (Sweden)

    Arseniy Karkach

    2006-11-01

    Full Text Available It has long been recognized that the patterns of growth play an important role in the evolution of age trajectories of fertility and mortality (Williams, 1957. Life history studies would benefit from a better understanding of strategies and mechanisms of growth, but still no comparative research on individual growth strategies has been conducted. Growth patterns and methods have been shaped by evolution and a great variety of them are observed. Two distinct patterns - determinate and indeterminate growth - are of a special interest for these studies since they present qualitatively different outcomes of evolution. We attempt to draw together studies covering growth in plant and animal species across a wide range of phyla focusing primarily on the noted qualitative features. We also review mathematical descriptions of growth, namely empirical growth curves and growth models, and discuss the directions of future research.

  9. Plant growth promoting rhizobacteria: Beneficial effects for healthy ...

    African Journals Online (AJOL)

    It is unanimously admitted that the chemical fertilizers and pesticides used in modern agriculture create a real environmental and public health problems. One of the promising solutions to substitute these agrochemicals products is the use of bio-resources, including plant growth promoting rhizobacteria (PGPR). The PGPR ...

  10. EFFICIENCY OF PLANT GROWTH PROMOTING RHIZOBACTERIA (PGPR IN SUGARCANE

    Directory of Open Access Journals (Sweden)

    Antonio Morgado González

    2015-10-01

    Full Text Available Plant growth promoting rhizobacteria (PGPR are an alternative for promoting sugarcane (Saccharum spp. development. Growth promotion was evaluated in sugarcane vitroplants inoculated separately with twenty-four strains of seven different bacterial species. Total indole synthesis and phosphate solubilization activity were determined in each strain. The experimental unit was one 5 L pot filled with a sterile mixture of farm soil-agrolite and one plant. The experimental design was completely random. Inoculation consisted of 1.0 mL of bacterial suspension (1 × 107 CFU. Plant height, stem diameter, number of shoots, leaf area and dry matter of shoot and root were determined every two weeks. The Ochrobactrum anthropi strains N208 and IMP311 and Pseudomonas luteola IMPCA244 had the highest production of total indoles (116.69, 115.70 and 117.34 µg mL-1, respectively. The Stenotrophomonas maltophilia strains CA158 and 79 exhibited the highest values of phosphate solubilization (222.43 and 216.38 µg mL-1, respectively. In general, plant height increased 27.75%, stem diameter 30.75%, number of tillers 38.5%, leaf area 49%, aerial dry matter 59.75% and root dry matter 59.5%. P. luteola, P. f luorescens, O. anthropi and S. maltophilia exhibited the highest values of the leaf area index, net assimilation, and relative and absolute growth rates. P. luteola IMPCA244, O. anthropi IMP311, Aeromonas salmonicida N264, Burkholderia cepacia N172, P. f luorescens N50 and S. maltophilia 79 promoted the highest values in different response variables throughout the study. Before using these strains as sugarcane biofertilizer, additional studies are required.

  11. Management strategies for nuclear power plant outages

    International Nuclear Information System (INIS)

    2006-01-01

    More competitive energy markets have significant implications for nuclear power plant operations, including, among others, the need for more efficient use of resources and effective management of plant activities such as on-line maintenance and outages. Outage management is a key factor for safe, reliable and economic plant performance and involves many aspects: plant policy, coordination of available resources, nuclear safety, regulatory and technical requirements, and all activities and work hazards, before and during the outage. The IAEA has produced this report on nuclear power plant outage management strategies to provide both a summary and an update of a follow-up to a series of technical documents related to practices regarding outage management and cost effective maintenance. The aim of this publication is to identify good practices in outage management: outage planning and preparation, outage execution and post-outage review. As in in the related technical documents, this report aims to communicate these practices in such a way that they can be used by operating organizations and regulatory bodies in Member States. The report was prepared as part of an IAEA project on continuous process improvement. The objective of this project is to increase Member State capabilities in improving plant performance and competitiveness through the utilization of proven engineering and management practices developed and transferred by the IAEA

  12. Synthesis of Gibberellic Acid Derivatives and Their Effects on Plant Growth

    Directory of Open Access Journals (Sweden)

    Hao Tian

    2017-04-01

    Full Text Available A series of novel C-3-OH substituted gibberellin derivatives bearing an amide group were designed and synthesized from the natural product gibberellic acid (GA3. Their activities on the plant growth regulation of rice and Arabidopsis were evaluated in vivo. Among these compounds, 10d and 10f exhibited appreciable inhibitory activities on rice (48.6% at 100 μmol/L and Arabidopsis (41.4% at 100 μmol/L, respectively. These results provide new insights into the design and synthesis of potential plant growth regulators.

  13. Achieving profitable growth in E and P: New strategies, business model

    International Nuclear Information System (INIS)

    Cavoulacos, P.; Deffarges, E.

    1997-01-01

    Major changes in the oil and gas environment during the last decade and a half have necessitated significant course corrections in upstream business strategies. Exogenous factors such as privatization and the opening of new opportunity areas have caused significant shifts in company strategies to drive growth, while lingering low commodity prices have applied continuous pressure to reduce costs. Successful upstream players have changed their strategies--from frontier exploration to development/production new ventures and on to gas and power plays--and built the capabilities necessary to achieve profitable growth. Moreover, these companies have adopted a new business model, an organization paradigm based on process-driven networks of business units, accountability and pay-for-performance, empowered multidisciplinary teams, and best practice sharing

  14. Analysis of the Connections between EU Economic Growth and the Lisbon Strategy

    OpenAIRE

    Marius-Corneliu MARINAŞ

    2010-01-01

    This research tries to offer an explanation for the motivation to implement the Lisbon Strategy, its main failures and its impact upon EU economic growth process. The Lisbon Strategy, which was adopted in 2000, should have resulted in the structural change of the European Union’s economy until 2010, if taking into consideration the promotion of a sustainable economic growth, which could encourage the increase of employment and the provision of economic and social cohesion...

  15. Long term growth of crop plants on experimental plots created among slag heaps.

    Science.gov (United States)

    Halecki, Wiktor; Klatka, Sławomir

    2018-01-01

    Suppression of plant growth is a common problem in post-mining reclaimed areas, as coarse texture of soils may increase nitrate leaching. Assessing feasibility of using solid waste (precipitated solid matter) produced by water and sewage treatment processes in field conditions is very important in mine soil reclamation. Our work investigated the possibility of plant growth in a degraded site covered with sewage-derived sludge material. A test area (21m × 18m) was established on a mine soil heap. Experimental plant species included Camelina sativa, Helianthus annuus, Festuca rubra, Miscanthus giganteus, Amaranthus cruentus, Brassica napus, Melilotus albus, Beta vulgaris, and Zea mays. ANOVA showed sufficient water content and acceptable physical properties of the soil in each year and layer in a multi-year period, indicating that these species were suitable for phytoremediation purposes. Results of trace elements assays indicated low degree of contamination caused by Carbocrash waste material and low potential ecological risk for all plant species. Detrended correspondence analysis revealed that total porosity and capillary porosity were the most important variables for the biosolids among all water content related properties. Overall, crop plants were found useful on heavily degraded land and the soil benefited from their presence. An addition of Carbocrash substrate to mine soil improved the initial stage of soil reclamation and accelerated plant growth. The use of this substrate in phytoremediation helped to balance the content of nutrients, promoted plant growth, and increased plant tolerance to salinity. Sewage sludge-amended biosolids may be applied directly to agricultural soil, not only in experimental conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Quantification of growth benefit of carnivorous plants from prey

    Czech Academy of Sciences Publication Activity Database

    Adamec, Lubomír

    2017-01-01

    Roč. 46, č. 3 (2017), s. 1-7 ISSN 0190-9215 Institutional support: RVO:67985939 Keywords : mineral cost and benefit * stimulation of roots * growth stimulation Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany

  17. Exogenous application of plant growth regulators increased the total ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-11-02

    Nov 2, 2009 ... the exogenous application of flavonoids reports plant growth regulation ... method used for extraction and quantification of endogenous gibberellins was ... 365 nm) while separation was done on a C18 reverse-phase HPLC.

  18. Growth Chambers on the International Space Station for Large Plants

    Science.gov (United States)

    Massa, Gioia D.; Wheeler, Raymond M.; Morrow, Robert C.; Levine, Howard G.

    2016-01-01

    The International Space Station (ISS) now has platforms for conducting research on horticultural plant species under LED (Light Emitting Diodes) lighting, and those capabilities continue to expand. The Veggie vegetable production system was deployed to the ISS as an applied research platform for food production in space. Veggie is capable of growing a wide array of horticultural crops. It was designed for low power usage, low launch mass and stowage volume, and minimal crew time requirements. The Veggie flight hardware consists of a light cap containing red (630 nanometers), blue, (455 nanometers) and green (530 nanometers) LEDs. Interfacing with the light cap is an extendable bellowsbaseplate for enclosing the plant canopy. A second large plant growth chamber, the Advanced Plant Habitat (APH), is will fly to the ISS in 2017. APH will be a fully controllable environment for high-quality plant physiological research. APH will control light (quality, level, and timing), temperature, CO2, relative humidity, and irrigation, while scrubbing any cabin or plant-derived ethylene and other volatile organic compounds. Additional capabilities include sensing of leaf temperature and root zone moisture, root zone temperature, and oxygen concentration. The light cap will have red (630 nm), blue (450 nm), green (525 nm), far red (730 nm) and broad spectrum white LEDs (4100K). There will be several internal cameras (visible and IR) to monitor and record plant growth and operations. Veggie and APH are available for research proposals.

  19. Effect of plant sterols and tannins on Phytophthora ramorum growth and sporulation

    Science.gov (United States)

    The acquisition of plant sterols, mediated via elicitins, is required for growth and sporulation of Phytophthora spp. In this paper, we looked at the interaction between elicitins, sterols, and tannins. When ground leaf tissue was added to growth media, P. ramorum growth and sporulation was greates...

  20. Root Traits and Phenotyping Strategies for Plant Improvement.

    Science.gov (United States)

    Paez-Garcia, Ana; Motes, Christy M; Scheible, Wolf-Rüdiger; Chen, Rujin; Blancaflor, Elison B; Monteros, Maria J

    2015-06-15

    Roots are crucial for nutrient and water acquisition and can be targeted to enhance plant productivity under a broad range of growing conditions. A current challenge for plant breeding is the limited ability to phenotype and select for desirable root characteristics due to their underground location. Plant breeding efforts aimed at modifying root traits can result in novel, more stress-tolerant crops and increased yield by enhancing the capacity of the plant for soil exploration and, thus, water and nutrient acquisition. Available approaches for root phenotyping in laboratory, greenhouse and field encompass simple agar plates to labor-intensive root digging (i.e., shovelomics) and soil boring methods, the construction of underground root observation stations and sophisticated computer-assisted root imaging. Here, we summarize root architectural traits relevant to crop productivity, survey root phenotyping strategies and describe their advantages, limitations and practical value for crop and forage breeding programs.

  1. Root Traits and Phenotyping Strategies for Plant Improvement

    Directory of Open Access Journals (Sweden)

    Ana Paez-Garcia

    2015-06-01

    Full Text Available Roots are crucial for nutrient and water acquisition and can be targeted to enhance plant productivity under a broad range of growing conditions. A current challenge for plant breeding is the limited ability to phenotype and select for desirable root characteristics due to their underground location. Plant breeding efforts aimed at modifying root traits can result in novel, more stress-tolerant crops and increased yield by enhancing the capacity of the plant for soil exploration and, thus, water and nutrient acquisition. Available approaches for root phenotyping in laboratory, greenhouse and field encompass simple agar plates to labor-intensive root digging (i.e., shovelomics and soil boring methods, the construction of underground root observation stations and sophisticated computer-assisted root imaging. Here, we summarize root architectural traits relevant to crop productivity, survey root phenotyping strategies and describe their advantages, limitations and practical value for crop and forage breeding programs.

  2. The effects of light-emitting diode lighting on greenhouse plant growth and quality

    Directory of Open Access Journals (Sweden)

    Margit Olle

    2013-06-01

    Full Text Available The aim of this study is to present the light emitting diode (LED technology for greenhouse plant lighting and to give an overview about LED light effects on photosynthetic indices, growth, yield and nutritional value in green vegetables and tomato, cucumber, sweet pepper transplants. The sole LED lighting, applied in closed growth chambers, as well as combinations of LED wavelengths with conventional light sources, fluorescent and high pressure sodium lamp light, and natural illumination in greenhouses are overviewed. Red and blue light are basal in the lighting spectra for green vegetables and tomato, cucumber, and pepper transplants; far red light, important for photomorphogenetic processes in plants also results in growth promotion. However, theoretically unprofitable spectral parts as green or yellow also have significant physiological effects on investigated plants. Presented results disclose the variability of light spectral effects on different plant species and different physiological indices.

  3. 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.

  4. 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.

  5. RESEARCH REGARDING THE POTENTIAL ACTIVITY OF SOME HETEROCYCLIC COMPOUNDS ON PLANTS GROWTH AND DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    OANA-IRINA PATRICIU

    2017-06-01

    Full Text Available It is well known that growth and morphogenesis of plant tissue cultures can be improved by small amounts of some organic compounds. Heterocyclic compounds such as chromanones and thiazoles derivatives, valuable because of their potential biological activities, have also been reported as pesticides, herbicides and plant-growth regulators. In the present study, different concentrations of chromanones and thiazoles derivatives were employed to evaluate their effects on plantlets growth of Ocimum basilicum L. and Echinacea purpurea L. The studied compounds were proved to be growth inhibitors at high concentrations. A growth stimulation effect was registered at low concentration.

  6. An Assessment of Engineered Calcium Oxalate Crystal Formation on Plant Growth and Development as a Step toward Evaluating Its Use to Enhance Plant Defense.

    Directory of Open Access Journals (Sweden)

    Paul A Nakata

    Full Text Available The establishment of new approaches to control chewing insects has been sought not only for direct use in reducing crop loss but also in managing resistance to the pesticides already in use. Engineered formation of calcium oxalate crystals is a potential strategy that could be developed to fulfill both these needs. As a step toward this development, this study investigates the effects of transforming a non-calcium oxalate crystal accumulating plant, Arabidopsis thaliana, into a crystal accumulating plant. Calcium oxalate crystal accumulating A. thaliana lines were generated by ectopic expression of a single bacterial gene encoding an oxalic acid biosynthetic enzyme. Biochemical and cellular studies suggested that the engineered A. thaliana lines formed crystals of calcium oxalate in a manner similar to naturally occurring crystal accumulating plants. The amount of calcium oxalate accumulated in leaves also reached levels similar to those measured in the leaves of Medicago truncatula in which the crystals are known to play a defensive role. Visual inspection of the different engineered lines, however, suggested a phenotypic consequence on plant growth and development with higher calcium oxalate concentrations. The restoration of a near wild-type plant phenotype through an enzymatic reduction of tissue oxalate supported this observation. Overall, this study is a first to provide initial insight into the potential consequences of engineering calcium oxalate crystal formation in non-crystal accumulating plants.

  7. The effect of plant growth regulators on optimization of tissue culture ...

    African Journals Online (AJOL)

    Mature seeds of four upland rice cultivars namely Kusan, Lamsan, Selasi and Siam were assessed for callus induction and plant regeneration on different concentrations and combinations of plant growth regulators, incorporated into MS (Murashige and Skoog) basal medium. Callus induction frequency was significantly ...

  8. Influence of plant growth regulators on development and ...

    African Journals Online (AJOL)

    Therefore propagation of the plant material by cell cultures and the extraction of potential pharmaceutical active compounds are of great interest. Calli were established on different media from roots and shoots of seedlings and softness and colour of the tissue were compared. Optimum growth of callus cultures was ...

  9. Modeling the growth of individuals in plant populations: local density variation in a strand population of Xanthium strumarium (Asteraceae).

    Science.gov (United States)

    Weiner, J; Kinsman, S; Williams, S

    1998-11-01

    We studied the growth of individual Xanthium strumarium plants growing at four naturally occurring local densities on a beach in Maine: (1) isolated plants, (2) pairs of plants ≤1 cm apart, (3) four plants within 4 cm of each other, and (4) discrete dense clumps of 10-39 plants. A combination of nondestructive measurements every 2 wk and parallel calibration harvests provided very good estimates of the growth in aboveground biomass of over 400 individual plants over 8 wk and afforded the opportunity to fit explicit growth models to 293 of them. There was large individual variation in growth and resultant size within the population and within all densities. Local crowding played a role in determining plant size within the population: there were significant differences in final size between all densities except pairs and quadruples, which were almost identical. Overall, plants growing at higher densities were more variable in growth and final size than plants growing at lower densities, but this was due to increased variation among groups (greater variation in local density and/or greater environmental heterogeneity), not to increased variation within groups. Thus, there was no evidence of size asymmetric competition in this population. The growth of most plants was close to exponential over the study period, but half the plants were slightly better fit by a sigmoidal (logistic) model. The proportion of plants better fit by the logistic model increased with density and with initial plant size. The use of explicit growth models over several growth intervals to describe stand development can provide more biological content and more statistical power than "growth-size" methods that analyze growth intervals separately.

  10. Low dose radiation and plant growth

    International Nuclear Information System (INIS)

    Kim, Sung Jae; Lee, Hae Youn; Park, Hong Sook

    2001-03-01

    Ionizing radiation includes cosmic radiation, earth radiation, radionuclides for the medical purpose and nuclear industry, fallout radiation. From the experimental results of various radiation effects on seeds or seedlings, it was found that germination rate, development, respiration rate, reproduction and blooming were accelerated compared with the control. In mammal, hormesis phenomenon manifested itself in increased disease resistance, lifespan, and decreased rate of tumor incidence. In plants, it was shown that germination, sprouting, growth, development, blooming and resistance to disease were accelerated

  11. Low dose radiation and plant growth

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Jae; Lee, Hae Youn; Park, Hong Sook

    2001-03-01

    Ionizing radiation includes cosmic radiation, earth radiation, radionuclides for the medical purpose and nuclear industry, fallout radiation. From the experimental results of various radiation effects on seeds or seedlings, it was found that germination rate, development, respiration rate, reproduction and blooming were accelerated compared with the control. In mammal, hormesis phenomenon manifested itself in increased disease resistance, lifespan, and decreased rate of tumor incidence. In plants, it was shown that germination, sprouting, growth, development, blooming and resistance to disease were accelerated.

  12. Effects of Plant Growth Regulators and Photoperiod on In

    African Journals Online (AJOL)

    Shahin

    using the combination of two plant growth regulators and same photoperiod. Key words: Tissue culture, ... they can be stored and transplanted directly into the field without an acclimatization ..... SAS user's guide. cary, NC: Statistical Analysis ...

  13. Oligosaccharins, brassinolides, and jasmonates: nontraditional regulators of plant growth, development, and gene expression.

    Science.gov (United States)

    Creelman, R A; Mullet, J E

    1997-07-01

    Each of the nontraditional plant hormones reviewed in this article, oligosaccharins, brassinolides, and JA, can exert major effects on plant growth and development. However, in many cases, the mechanisms by which these compounds are involved in the endogenous regulation of morphogenesis remain to be established. Nevertheless, the use of mutant or transgenic plants with altered levels or perception of these hormones is leading to phenomenal increases in our understanding of the roles they play in the life cycle of plants. It is likely that in the future, novel modulators of plant growth and development will be identified; some will perhaps be related to the peptide encoded by ENOD40 (Van de Sande et al., 1996), which modifies the action of auxin.

  14. Predicting long-term growth in students' mathematics achievement: the unique contributions of motivation and cognitive strategies.

    Science.gov (United States)

    Murayama, Kou; Pekrun, Reinhard; Lichtenfeld, Stephanie; Vom Hofe, Rudolf

    2013-01-01

    This research examined how motivation (perceived control, intrinsic motivation, and extrinsic motivation), cognitive learning strategies (deep and surface strategies), and intelligence jointly predict long-term growth in students' mathematics achievement over 5 years. Using longitudinal data from six annual waves (Grades 5 through 10; Mage  = 11.7 years at baseline; N = 3,530), latent growth curve modeling was employed to analyze growth in achievement. Results showed that the initial level of achievement was strongly related to intelligence, with motivation and cognitive strategies explaining additional variance. In contrast, intelligence had no relation with the growth of achievement over years, whereas motivation and learning strategies were predictors of growth. These findings highlight the importance of motivation and learning strategies in facilitating adolescents' development of mathematical competencies. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

  15. GDP-D-mannose epimerase regulates male gametophyte development, plant growth and leaf senescence in Arabidopsis.

    Science.gov (United States)

    Qi, Tiancong; Liu, Zhipeng; Fan, Meng; Chen, Yan; Tian, Haixia; Wu, Dewei; Gao, Hua; Ren, Chunmei; Song, Susheng; Xie, Daoxin

    2017-09-04

    Plant GDP-D-mannose epimerase (GME) converts GDP-D-mannose to GDP-L-galactose, a precursor of both L-ascorbate (vitamin C) and cell wall polysaccharides. However, the genetic functions of GME in Arabidopsis are unclear. In this study, we found that mutations in Arabidopsis GME affect pollen germination, pollen tube elongation, and transmission and development of the male gametophyte through analysis of the heterozygous GME/gme plants and the homozygous gme plants. Arabidopsis gme mutants also exhibit severe growth defects and early leaf senescence. Surprisingly, the defects in male gametophyte in the gme plants are not restored by L-ascorbate, boric acid or GDP-L-galactose, though boric acid rescues the growth defects of the mutants, indicating that GME may regulate male gametophyte development independent of L-ascorbate and GDP-L-galactose. These results reveal key roles for Arabidopsis GME in reproductive development, vegetative growth and leaf senescence, and suggest that GME regulates plant growth and controls male gametophyte development in different manners.

  16. Plant Growth-Promoting Rhizobacteria Enhance Salinity Stress Tolerance in Okra through ROS-Scavenging Enzymes

    Directory of Open Access Journals (Sweden)

    Sheikh Hasna Habib

    2016-01-01

    Full Text Available Salinity is a major environmental stress that limits crop production worldwide. In this study, we characterized plant growth-promoting rhizobacteria (PGPR containing 1-aminocyclopropane-1-carboxylate (ACC deaminase and examined their effect on salinity stress tolerance in okra through the induction of ROS-scavenging enzyme activity. PGPR inoculated okra plants exhibited higher germination percentage, growth parameters, and chlorophyll content than control plants. Increased antioxidant enzyme activities (SOD, APX, and CAT and upregulation of ROS pathway genes (CAT, APX, GR, and DHAR were observed in PGPR inoculated okra plants under salinity stress. With some exceptions, inoculation with Enterobacter sp. UPMR18 had a significant influence on all tested parameters under salt stress, as compared to other treatments. Thus, the ACC deaminase-containing PGPR isolate Enterobacter sp. UPMR18 could be an effective bioresource for enhancing salt tolerance and growth of okra plants under salinity stress.

  17. Large Plant Growth Chambers: Flying Soon on a Space Station near You!

    Science.gov (United States)

    Massa, Gioia D.; Morrow, Robert C.; Levine, Howard G.

    2014-01-01

    The International Space Station (ISS) now has platforms for conducting research on horticultural plant species, and those capabilities continue to grow. The Veggie vegetable production system will be deployed to the ISS in Spring of 2014 to act as an applied research platform with goals of studying food production in space, providing the crew with a source of fresh food, allowing behavioral health and plant microbiology experimentation, and being a source of recreation and enjoyment for the crew. Veggie was conceived, designed, and constructed by Orbital Technologies Corporation (ORBITEC, Madison, WI). Veggie is the largest plant growth chamber that NASA has flown to date, and is capable of growing a wide array of horticultural crops. It was designed for low energy usage, low launch mass and stowage volume, and minimal crew time requirements. The Veggie flight hardware consists of a light cap containing red (630 nanometers), blue, (455 nanometers) and green (530 nanometers) light emitting diodes. Interfacing with the light cap is an extendable bellows baseplate secured to the light cap via magnetic closures and stabilized with extensible flexible arms. The baseplate contains vents allowing air from the ISS cabin to be pulled through the plant growth area by a fan in the light cap. The baseplate holds a Veggie root mat reservoir that will supply water to plant pillows attached via elastic cords. Plant pillows are packages of growth media and seeds that will be sent to ISS dry and installed and hydrated on orbit. Pillows can be constructed in various sizes for different plant types. Watering will be via passive wicking from the root mat to the pillows. Science procedures will include photography or videography, plant thinning, pollination, harvesting, microbial sampling, water sampling, etcetera. Veggie is one of the ISS flight options currently available for research investigations on plants. The Plant Habitat (PH) is being designed and constructed through a NASA

  18. The demographic consequences of mutualism: ants increase host-plant fruit production but not population growth.

    Science.gov (United States)

    Ford, Kevin R; Ness, Joshua H; Bronstein, Judith L; Morris, William F

    2015-10-01

    The impact of mutualists on a partner's demography depends on how they affect the partner's multiple vital rates and how those vital rates, in turn, affect population growth. However, mutualism studies rarely measure effects on multiple vital rates or integrate them to assess the ultimate impact on population growth. We used vital rate data, population models and simulations of long-term population dynamics to quantify the demographic impact of a guild of ant species on the plant Ferocactus wislizeni. The ants feed at the plant's extrafloral nectaries and attack herbivores attempting to consume reproductive organs. Ant-guarded plants produced significantly more fruit, but ants had no significant effect on individual growth or survival. After integrating ant effects across these vital rates, we found that projected population growth was not significantly different between unguarded and ant-guarded plants because population growth was only weakly influenced by differences in fruit production (though strongly influenced by differences in individual growth and survival). However, simulations showed that ants could positively affect long-term plant population dynamics through services provided during rare but important events (herbivore outbreaks that reduce survival or years of high seedling recruitment associated with abundant precipitation). Thus, in this seemingly clear example of mutualism, the interaction may actually yield no clear benefit to plant population growth, or if it does, may only do so through the actions of the ants during rare events. These insights demonstrate the value of taking a demographic approach to studying the consequences of mutualism.

  19. The physical growth of Oreochromis niloticus and three plant species on the aquaponic technology

    Science.gov (United States)

    Mustikasari, A.; Marwoto, P.; Iswari, R. S.

    2018-03-01

    The physical growth of Oreochromis niloticus fish and three types of plants consist of Ipomoea Aquatica, Brassica rapa, and Capsicum annuum on the aquaponic technology have been studied. The aquaponic technology system has been done with 200 fishes m-3, water pump with 15 watts solar energy panel, physical and biological filter, and deep flow technique (DFT). In this study, we have reported that the specific growth rate (SGR), survival (SR), Feed conversion ratio (FCR), and Wet weight (W) are used as the physical growth indicator of Oreochromis niloticus fish, while the length and the number of leaves of plants are used as the physical growth indicator of plants. The physical growth of Oreochromis niloticus fish showed that SGR is 5,56% day-1, SR is 97,67%, FCR is 0,92g and the wet weight is 1220g. The physical growth of the plant in aquaponic technology systems has been compared with the hydroponic treatment systems as controls. Analysis with t-test shows that physical growth of Ipomoea Aquatica and Brassica rapa has no significant difference respectively, whereas Capsicum annuum has significant differences compared with controls. Also, Brassica rapa in the aquaponic technology system shows a more yellow leaf color than the control. Based on these results, we conclude that aquaponic technology system provides effective results for the physical growth of Oreochromis niloticus with Ipomoea Aquatica, while additional nutrients for the both Brassica rapa and Capsicum annuum are required.

  20. Clonal growth strategy, diversity and structure: A spatiotemporal response to sedimentation in tropical Cyperus papyrus swamps.

    Science.gov (United States)

    Geremew, Addisie; Stiers, Iris; Sierens, Tim; Kefalew, Alemayehu; Triest, Ludwig

    2018-01-01

    Land degradation and soil erosion in the upper catchments of tropical lakes fringed by papyrus vegetation can result in a sediment load gradient from land to lakeward. Understanding the dynamics of clonal modules (ramets and genets) and growth strategies of plants on such a gradient in both space and time is critical for exploring a species adaptation and processes regulating population structure and differentiation. We assessed the spatial and temporal dynamics in clonal growth, diversity, and structure of an emergent macrophyte, Cyperus papyrus (papyrus), in response to two contrasting sedimentation regimes by combining morphological traits and genotype data using 20 microsatellite markers. A total of 636 ramets from six permanent plots (18 x 30 m) in three Ethiopian papyrus swamps, each with discrete sedimentation regimes (high vs. low) were sampled for two years. We found that ramets under the high sedimentation regime (HSR) were significantly clumped and denser than the sparse and spreading ramets under the low sedimentation regime (LSR). The HSR resulted in significantly different ramets with short culm height and girth diameter as compared to the LSR. These results indicated that C. papyrus ameliorates the effect of sedimentation by shifting clonal growth strategy from guerrilla (in LSR) to phalanx (in HSR). Clonal richness, size, dominance, and clonal subrange differed significantly between sediment regimes and studied time periods. Each swamp under HSR revealed a significantly high clonal richness (R = 0.80) as compared to the LSR (R = 0.48). Such discrepancy in clonal richness reflected the occurrence of initial and repeated seedling recruitment strategies as a response to different sedimentation regimes. Overall, our spatial and short-term temporal observations highlighted that HSR enhances clonal richness and decreases clonal subrange owing to repeated seedling recruitment and genets turnover.

  1. Effects of different plant growth regulators on blueberry fruit quality

    Science.gov (United States)

    Zhang, X. C.; Zhu, Y. Q.; Wang, Y. N.; Luo, C.; Wang, X.

    2017-08-01

    In order to understand the effects of different plant growth regulators (PGRs) on blueberry fruit growth, various concentrations of Abscisic acid (ABA), Methyl jasmonate (MJ), Brassinolide (BR), Melatonin (MT) were sprayed on blueberry cv. ‘Brigita’ fruits. The results showed that all the PGRs put into effect on improving the quality of blueberry fruit. Comparing with the control plants no PGR spraying,300 mg/L of MT treatment promoted effectively accumulation of the soluble sugar. ABA 20mg/L treatment in-creased effectively accumulation of anthocyanin, and significantly decreased titratable acid content. The treatment of MJ 10mg/L improved significantly the soluble solid content. The effect of the four PGRs treatments on appearance did not show obvious difference.

  2. 15. international conference on plant growth substances: Program -- Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    Since the 14th Conference in Amsterdam in 1991, progress in plant hormone research and developmental plant biology has been truly astonishing. The five ``classical`` plant hormones, auxin, gibberellin, cytokinin, ethylene, and abscisic acid, have been joined by a number of new signal molecules, e.g., systemin, jasmonic acid, salicylic acid, whose biosynthesis and functions are being understood in ever greater detail. Molecular genetics has opened new vistas in an understanding of transduction pathways that regulate developmental processes in response to hormonal and environmental signals. The program of the 15th Conference includes accounts of this progress and brings together scientists whose work focuses on physiological, biochemical, and chemical aspects of plant growth regulation. This volume contains the abstracts of papers presented at this conference.

  3. Temperature extremes: Effect on plant growth and development

    Directory of Open Access Journals (Sweden)

    Jerry L. Hatfield

    2015-12-01

    Full Text Available Temperature is a primary factor affecting the rate of plant development. Warmer temperatures expected with climate change and the potential for more extreme temperature events will impact plant productivity. Pollination is one of the most sensitive phenological stages to temperature extremes across all species and during this developmental stage temperature extremes would greatly affect production. Few adaptation strategies are available to cope with temperature extremes at this developmental stage other than to select for plants which shed pollen during the cooler periods of the day or are indeterminate so flowering occurs over a longer period of the growing season. In controlled environment studies, warm temperatures increased the rate of phenological development; however, there was no effect on leaf area or vegetative biomass compared to normal temperatures. The major impact of warmer temperatures was during the reproductive stage of development and in all cases grain yield in maize was significantly reduced by as much as 80−90% from a normal temperature regime. Temperature effects are increased by water deficits and excess soil water demonstrating that understanding the interaction of temperature and water will be needed to develop more effective adaptation strategies to offset the impacts of greater temperature extreme events associated with a changing climate.

  4. ARADISH - Development of a Standardized Plant Growth Chamber for Experiments in Gravitational Biology Using Ground Based Facilities

    Science.gov (United States)

    Schüler, Oliver; Krause, Lars; Görög, Mark; Hauslage, Jens; Kesseler, Leona; Böhmer, Maik; Hemmersbach, Ruth

    2016-06-01

    Plant development strongly relies on environmental conditions. Growth of plants in Biological Life Support Systems (BLSS), which are a necessity to allow human survival during long-term space exploration missions, poses a particular problem for plant growth, as in addition to the traditional environmental factors, microgravity (or reduced gravity such as on Moon or Mars) and limited gas exchange hamper plant growth. Studying the effects of reduced gravity on plants requires real or simulated microgravity experiments under highly standardized conditions, in order to avoid the influence of other environmental factors. Analysis of a large number of biological replicates, which is necessary for the detection of subtle phenotypical differences, can so far only be achieved in Ground Based Facilities (GBF). Besides different experimental conditions, the usage of a variety of different plant growth chambers was a major factor that led to a lack of reproducibility and comparability in previous studies. We have developed a flexible and customizable plant growth chamber, called ARAbidopsis DISH (ARADISH), which allows plant growth from seed to seedling, being realized in a hydroponic system or on Agar. By developing a special holder, the ARADISH can be used for experiments with Arabidopsis thaliana or a plant with a similar habitus on common GBF hardware, including 2D clinostats and Random Positioning Machines (RPM). The ARADISH growth chamber has a controlled illumination system of red and blue light emitting diodes (LED), which allows the user to apply defined light conditions. As a proof of concept we tested a prototype in a proteomic experiment in which plants were exposed to simulated microgravity or a 90° stimulus. We optimized the design and performed viability tests after several days of growth in the hardware that underline the utility of ARADISH in microgravity research.

  5. Urban plant physiology: adaptation-mitigation strategies under permanent stress.

    Science.gov (United States)

    Calfapietra, Carlo; Peñuelas, Josep; Niinemets, Ülo

    2015-02-01

    Urban environments that are stressful for plant function and growth will become increasingly widespread in future. In this opinion article, we define the concept of 'urban plant physiology', which focuses on plant responses and long term adaptations to urban conditions and on the capacity of urban vegetation to mitigate environmental hazards in urbanized settings such as air and soil pollution. Use of appropriate control treatments would allow for studies in urban environments to be comparable to expensive manipulative experiments. In this opinion article, we propose to couple two approaches, based either on environmental gradients or manipulated gradients, to develop the concept of urban plant physiology for assessing how single or multiple environmental factors affect the key environmental services provided by urban forests. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. In Vitro and In Vivo Plant Growth Promoting Activities and DNA Fingerprinting of Antagonistic Endophytic Actinomycetes Associates with Medicinal Plants.

    Science.gov (United States)

    Passari, Ajit Kumar; Mishra, Vineet Kumar; Gupta, Vijai Kumar; Yadav, Mukesh Kumar; Saikia, Ratul; Singh, Bhim Pratap

    2015-01-01

    Endophytic actinomycetes have shown unique plant growth promoting as well as antagonistic activity against fungal phytopathogens. In the present study forty-two endophytic actinomycetes recovered from medicinal plants were evaluated for their antagonistic potential and plant growth-promoting abilities. Twenty-two isolates which showed the inhibitory activity against at least one pathogen were subsequently tested for their plant-growth promoting activities and were compared genotypically using DNA based fingerprinting, including enterobacterial repetitive intergenic consensus (ERIC) and BOX repetitive elements. Genetic relatedness based on both ERIC and BOX-PCR generates specific patterns corresponding to particular genotypes. Exponentially grown antagonistic isolates were used to evaluate phosphate solubilization, siderophores, HCN, ammonia, chitinase, indole-3-acetic acid production, as well as antifungal activities. Out of 22 isolates, the amount of indole-3-acetic acid (IAA) ranging between 10-32 μg/ml was produced by 20 isolates and all isolates were positive for ammonia production ranging between 5.2 to 54 mg/ml. Among 22 isolates tested, the amount of hydroxamate-type siderophores were produced by 16 isolates ranging between 5.2 to 36.4 μg/ml, while catechols-type siderophores produced by 5 isolates ranging from 3.2 to 5.4 μg/ml. Fourteen isolates showed the solubilisation of inorganic phosphorous ranging from 3.2 to 32.6 mg/100ml. Chitinase and HCN production was shown by 19 and 15 different isolates, respectively. In addition, genes of indole acetic acid (iaaM) and chitinase (chiC) were successively amplified from 20 and 19 isolates respectively. The two potential strains Streptomyces sp. (BPSAC34) and Leifsonia xyli (BPSAC24) were tested in vivo and improved a range of growth parameters in chilli (Capsicum annuum L.) under greenhouse conditions. This study is the first published report that actinomycetes can be isolated as endophytes from within these

  7. Nitrogen for growth of stock plants and production of strawberry runner tips

    Directory of Open Access Journals (Sweden)

    Djeimi Isabel Janisch

    2012-01-01

    Full Text Available The objective of this research was to determine growth and dry matter partitioning among organs of strawberry stock plants under five Nitrogen concentrations in the nutrient solution and its effects on emission and growth of runner tips. The experiment was carried out under greenhouse conditions, from September 2010 to March 2011, in a soilless system with Oso Grande and Camino Real cultivars. Nitrogen concentrations of 5.12, 7.6, 10.12 (control, 12.62 and 15.12 mmol L-1 in the nutrient solution were studied in a 5x2 factorial randomised experimental design. All runner tips bearing at least one expanded leaf (patent requested were collected weekly and counted during the growth period. The number of leaves, dry matter (DM of leaves, crown and root, specific leaf area and leaf area index (LAI was determined at the final harvest. Increasing N concentration in the nutrient solution from 5.12 to 15.12 mmol L-1 reduces growth of crown, roots and LAI of strawberry stock plants but did not affect emission and growth of runner tips. It was concluded that for the commercial production of plug plants the optimal nitrogen concentration in the nutrient solution should be 5.12 mmol L-1.

  8. Strategy for improving instrumentation and control in operating nuclear power plants

    International Nuclear Information System (INIS)

    Abad Bassols, L.; Nino Perote, R.

    1996-01-01

    There are three basic reasons why nuclear power plants need to systematically upgrade their instrumentation and control equipment: Obsolete instrumentation and lack spares Little capacity of flexibility for extension Possibility of attaining better systems integration and improving systems-operations interface This article shows how to approach these issues using the following strategies: Use of distributed control systems and PLCs for control, signalling, command, communications, etc, in both nuclear and conventional applications Upgrading of process instrumentation equipment, sensors, transmitters, etc Upgrading of alarm-signalling systems In each group of equipment items consideration should be given to: Aspects regarding manufacturers-suppliers Effects on design, adaptation and documentation of operating plants Effects on the training and handling skills of operation and maintenance staff Strategy for incorporating the new system into the Plant with minimum impact on operation (Author)

  9. Protocol: optimising hydroponic growth systems for nutritional and physiological analysis of Arabidopsis thaliana and other plants

    Science.gov (United States)

    2013-01-01

    Background Hydroponic growth systems are a convenient platform for studying whole plant physiology. However, we found through trialling systems as they are described in the literature that our experiments were frequently confounded by factors that affected plant growth, including algal contamination and hypoxia. We also found the way in which the plants were grown made them poorly amenable to a number of common physiological assays. Results The drivers for the development of this hydroponic system were: 1) the exclusion of light from the growth solution; 2) to simplify the handling of individual plants, and 3) the growth of the plant to allow easy implementation of multiple assays. These aims were all met by the use of pierced lids of black microcentrifuge tubes. Seed was germinated on a lid filled with an agar-containing germination media immersed in the same solution. Following germination, the liquid growth media was exchanged with the experimental solution, and after 14-21 days seedlings were transferred to larger tanks with aerated solution where they remained until experimentation. We provide details of the protocol including composition of the basal growth solution, and separate solutions with altered calcium, magnesium, potassium or sodium supply whilst maintaining the activity of the majority of other ions. We demonstrate the adaptability of this system for: gas exchange measurement on single leaves and whole plants; qRT-PCR to probe the transcriptional response of roots or shoots to altered nutrient composition in the growth solution (we demonstrate this using high and low calcium supply); producing highly competent mesophyll protoplasts; and, accelerating the screening of Arabidopsis transformants. This system is also ideal for manipulating plants for micropipette techniques such as electrophysiology or SiCSA. Conclusions We present an optimised plant hydroponic culture system that can be quickly and cheaply constructed, and produces plants with similar

  10. Resins characterization strategy at Kozloduy Nuclear Power Plant

    International Nuclear Information System (INIS)

    Fenoy, A.; González, R.; Molleda, P.; Sánchez, L.; Herrera, J.

    2013-01-01

    The Consortium ENSA- Gas Natural Fenosa Engineering has a contract with Kozloduy Nuclear Power Plant (KNPP) for the retrieval and conditioning of the resins. Before that, the project deals with resins characterization to verify the fulfillment the Bulgarian authorities’ requirements. The project includes all the resins generated during the operation of the BACKGROUND Resins characterization strategy at Kozloduy Nuclear Power Plant units 1, 2, 3 and 4, which were stored into six big dimensions tanks: four low tanks and two intermediate tanks. They only have a manhole above for tanks access. The methodology and the progress of the work are presented

  11. Ligand Receptor-Mediated Regulation of Growth in Plants.

    Science.gov (United States)

    Haruta, Miyoshi; Sussman, Michael R

    2017-01-01

    Growth and development of multicellular organisms are coordinately regulated by various signaling pathways involving the communication of inter- and intracellular components. To form the appropriate body patterns, cellular growth and development are modulated by either stimulating or inhibiting these pathways. Hormones and second messengers help to mediate the initiation and/or interaction of the various signaling pathways in all complex multicellular eukaryotes. In plants, hormones include small organic molecules, as well as larger peptides and small proteins, which, as in animals, act as ligands and interact with receptor proteins to trigger rapid biochemical changes and induce the intracellular transcriptional and long-term physiological responses. During the past two decades, the availability of genetic and genomic resources in the model plant species, Arabidopsis thaliana, has greatly helped in the discovery of plant hormone receptors and the components of signal transduction pathways and mechanisms used by these immobile but highly complex organisms. Recently, it has been shown that two of the most important plant hormones, auxin and abscisic acid (ABA), act through signaling pathways that have not yet been recognized in animals. For example, auxins stimulate cell elongation by bringing negatively acting transcriptional repressor proteins to the proteasome to be degraded, thus unleashing the gene expression program required for increasing cell size. The "dormancy" inducing hormone, ABA, binds to soluble receptor proteins and inhibits a specific class of protein phosphatases (PP2C), which activates phosphorylation signaling leading to transcriptional changes needed for the desiccation of the seeds prior to entering dormancy. While these two hormone receptors have no known animal counterparts, there are also many similarities between animal and plant signaling pathways. For example, in plants, the largest single gene family in the genome is the protein kinase

  12. Vegetative growth response of cotton plants due to growth regulator supply via seeds

    Directory of Open Access Journals (Sweden)

    João Vitor Ferrari

    2015-08-01

    Full Text Available The global cotton industry is distinguished by its numerous industrial uses of the plume as well as by high production costs. Excessive vegetative growth can interfere negatively with productivity, and thus, applying growth regulators is essential for the development of the cotton culture. The objective of this study was to evaluate the development and yield of the cotton cultivar FMT 701 with the application of mepiquat chloride to seeds and leaves. The experimental design used a randomized block design with four replications, arranged in bands.The treatments consisted of mepiquat chloride rates (MC (0, 4, 6, 8 and 10 g a.i. kg-1 of seeds applied directly to the cotton seeds and MC management by foliar spray using a 250 mL ha-1 rates that was administered under the following conditions: divided into four applications (35, 45, 55 and 65 days after emergence; as a single application at 70 days; and without the application of the product. The mepiquat chloride applied to cotton seeds controls the initial plant height and stem diameter, while foliar application reduces the height of the plants. After application to seed, foliar spraying MC promotes increase mass of 20 bolls, however no direct influence amount bolls per plant and yield of cotton seed. Higher cotton seed yield was obtained with a rate of 3.4 g a.i. MC kg-1 seeds.

  13. Artificial topography changes the growth strategy of Spartina alterniflora, case study with wave exposure as a comparison.

    Science.gov (United States)

    Hong, Hualong; Dai, Minyue; Lu, Haoliang; Liu, Jingchun; Zhang, Jie; Chen, Chaoqi; Xia, Kang; Yan, Chongling

    2017-11-17

    This paper reports findings about the growth of Spartina alterniflora (Loisel.) near an engineered coastal protection defences to discover the potential influences on vegetation growth from the artificial topography. Impacts of the artificial topography on the sediment element composition were detected by comparing the fixed effects caused by artificial topography and wave exposure using linear mixed models. Surficial sediments under the impacts of artificial topography contain elevated levels of biogenic elements and heavy metals, including C (and organic carbon), N, S, Al, Fe, Mn, Cu, Zn, As, Cd, Cr, Ni, and Pb. The results showed that element enrichment caused by artificial topography reduced the vegetation sexual reproduction. Contrary to the potential inhibition caused by direct wave exposure, which was due to the biomass accumulation limit, the inhibition caused by artificial topography was related to the transition of growth strategy. The contents of Cu, Mn, N, Ni, S and As in the sediments were critical in considering the relationship between the change in the sediment element composition and the alteration in the plant growth. Our study emphasizes the importance of rethinking the impacts of coastal development projects, especially regarding the heterogeneity of sediment element composition and its ecological consequences.

  14. Promotion of plant growth by Pseudomonas fluorescens strain SS101 via novel volatile organic compounds

    NARCIS (Netherlands)

    Park, Yong-Soon; Dutta, Swarnalee; Ann, Mina; Raaijmakers, Jos M.; Park, Kyungseok

    2015-01-01

    Abstract Volatile organic compounds (VOCs) from plant growth-promoting rhizobacteria (PGPR) play key roles in modulating plant growth and induced systemic resistance (ISR) to pathogens. Despite their significance, the physiological functions of the specific VOCs produced by Pseudomonas fluorescens

  15. A model to explain plant growth promotion traits: a multivariate analysis of 2,211 bacterial isolates.

    Directory of Open Access Journals (Sweden)

    Pedro Beschoren da Costa

    Full Text Available Plant growth-promoting bacteria can greatly assist sustainable farming by improving plant health and biomass while reducing fertilizer use. The plant-microorganism-environment interaction is an open and complex system, and despite the active research in the area, patterns in root ecology are elusive. Here, we simultaneously analyzed the plant growth-promoting bacteria datasets from seven independent studies that shared a methodology for bioprospection and phenotype screening. The soil richness of the isolate's origin was classified by a Principal Component Analysis. A Categorical Principal Component Analysis was used to classify the soil richness according to isolate's indolic compound production, siderophores production and phosphate solubilization abilities, and bacterial genera composition. Multiple patterns and relationships were found and verified with nonparametric hypothesis testing. Including niche colonization in the analysis, we proposed a model to explain the expression of bacterial plant growth-promoting traits according to the soil nutritional status. Our model shows that plants favor interaction with growth hormone producers under rich nutrient conditions but favor nutrient solubilizers under poor conditions. We also performed several comparisons among the different genera, highlighting interesting ecological interactions and limitations. Our model could be used to direct plant growth-promoting bacteria bioprospection and metagenomic sampling.

  16. Pattern of growth and 14C-assimilates distributions in relation to photosynthesis in radish plants treated with growth substances

    Directory of Open Access Journals (Sweden)

    Z. Starck

    2015-01-01

    Full Text Available In a series of radish plants, with very thin hypocotyl and with a normal storage organ, the rates of photosynthesis, photorespiration and dark respiration did not differ. Therefore, the conclusion may be advanced, that translocation to the swollen hypocotyl is not determinated by the photosynthetic productivity, but rather the by storage capacity. To check it this is connected with an unbalanced hormonal content, plants were treated with lanoline paste, with IAA, GA3, zeatin and all three in mixture or with injections of GA3-water solution into the swollen hypocotyl. In young radish plants, with high rate of growth of aerial parts, treatment with the above mentioned substances stimulated 14CO2-assimilation and increased retention of assimilates in 14C-donors, probably owing to retardation of their senescence. It increased the competition for photosynthates between shoot and storage organ. In older plants, in the stage of accumulation of nutrients in the swollen hypocotyl, IAA +GA3+zeatin did not affect 14CO2-assimilation, but in plants treated with growth regulators separately, assimilation decreased; IAA and GA3 stimulated transport and accumulation of labelled substances in the swollen hypocotyl. On the basis of experimental data the conclusion may be advanced that responsiveness of the particular organs and processes to growth regulators depends on the stage of plant development. Phytohormone did not changed quantitatively the pattern of 14C-assimilates distribution. They stimulated processes with preference for particular stages of development.

  17. Legacy effects of drought on plant growth and the soil food web

    DEFF Research Database (Denmark)

    de Vries, Franciska; Liiri, Mira; Strandmark, Lisa Bjørnlund

    2012-01-01

    the potential to feed back on each other's performance. In a greenhouse experiment, we compared legacy effects of repeated drought on plant growth and the soil food web in two contrasting land-use systems: extensively managed grassland, rich in C and with a fungal-based food web, and intensively managed wheat...... lower in C and with a bacterial-based food web. Moreover, we assessed the effect of plant presence on the recovery of the soil food web after drought. Drought legacy effects increased plant growth in both systems, and a plant strongly reduced N leaching. Fungi, bacteria, and their predators were more...... resilient after drought in the grassland soil than in the wheat soil. The presence of a plant strongly affected the composition of the soil food web, and alleviated the effects of drought for most trophic groups, regardless of the system. This effect was stronger for the bottom trophic levels, whose...

  18. Diffusivity-Based Characterization of Plant Growth Media for Earth and Space

    DEFF Research Database (Denmark)

    Chamindu, Deepagoda; Møldrup, Per; Jones, Scot B.

    will likely fulfill diffusion requirements when designing safe plant growth media for earth and space. The CWD concept was also applied to a natural volcanic ash soil (Nishi-Tokyo, Japan), and natural volcanic ash soil exhibited a CWD performance fully comparable with the best among the aggregated growth...

  19. Development of a qPCR strategy to select bean genes involved in plant defence response and regulated by the Trichoderma velutinum - Rhizoctonia solani interaction

    Directory of Open Access Journals (Sweden)

    Sara Mayo

    2016-08-01

    Full Text Available Bean production is affected by a wide diversity of fungal pathogens, among them Rhizoctonia solani is one of the most important. A strategy to control bean infectious diseases, mainly those caused by fungi, is based on the use of biocontrol agents that can reduce the negative effects of plant pathogens and also can promote positive responses in the plant. Trichoderma is a fungal genus that is able to induce the expression of genes involved in plant defence response and also to promote plant growth, root development and nutrient uptake. In this article, a strategy that combines in silico analysis and real time PCR to detect additional bean defence-related genes, regulated by the presence of Trichoderma velutinum and/or R. solani has been applied. Based in this strategy, from From the 48 bean genes initially analysed, 14 were selected, and only WRKY33, CH5b and hGS showed an up-regulatory response in the presence of T. velutinum. The other genes were or not affected (OSM34 or down-regulated by the presence of this fungus. R. solani infection resulted in a down-regulation of most of the genes analyzed, except PR1, OSM34 and CNGC2 that were not affected, and the presence of both, T. velutinum and R. solani, up-regulates hGS and down-regulates all the other genes analyzed, except CH5b which was not significantly affected.As conclusion, the strategy described in the present work has been shown to be effective to detect genes involved in plant defence, which respond to the presence of a biocontrol agent or to a pathogen and also to the presence of both. The selected genes show significant homology with previously described plant defence genes and they are expressed in bean leaves of plants treated with T. velutinum and/or infected with R. solani.

  20. Characterization of plant growth-promoting traits of free-living diazotrophic bacteria and their inoculation effects on growth and nitrogen uptake of crop plants.

    Science.gov (United States)

    Islam, Md Rashedul; Madhaiyan, M; Deka Boruah, Hari P; Yim, Woojong; Lee, Gillseung; Saravanan, V S; Fu, Qingling; Hu, Hongqing; Sa, Tongmin

    2009-10-01

    The search for diverse plant growth-promoting (PGP) diazotrophic bacteria is gaining momentum as efforts are made to exploit them as biofertilizers for various economically important crops. In the present study, 17 diazotrophic strains belonging to eight different genera isolated from rice paddy fields were screened for multiple PGP traits and evaluated for their inoculation effects on canola and rice plants. All of the strains tested positive for 1- aminocyclopropane-1-carboxylate (ACC) deaminase activity and production of indole 3-acetic acid (IAA) and ammonia (NH3). Additionally, four of the strains were able to solubilize phosphorus (P), five tested positive for zinc (Zn) solubilization and sulfur (S) oxidation, and eight strains produced siderophores. Based on the presence of multiple PGP traits, 10 strains were selected for inoculation studies. Treatment with Herbaspirillum sp. RFNB26 resulted in maximum root length (54.3%), seedling vigor, and dry biomass in canola, whereas Paenibacillus sp. RFNB4 exhibited the lowest activity under gnotobiotic conditions. However, under pot culture conditions, Paenibacillus sp. RFNB4 significantly increased plant height and dry biomass production by 42.3% and 29.5%, respectively. Canola plants and rhizosphere soils inoculated with Bacillus sp. RFNB6 exhibited significantly higher nitrogenase activity. In greenhouse experiments, Serratia sp. RFNB18 increased rice plant height by 35.1%, Xanthomonas sp. RFNB24 enhanced biomass production by 84.6%, and rice rhizosphere soils inoculated with Herbaspirillum sp. RFNB26 exhibited the highest nitrogenase activity. Our findings indicate that most of the selected strains possess multiple PGP properties that significantly improve the growth parameters of the two plants when tested under controlled conditions.

  1. Effects of sulfur nutrition on phytotoxicity and growth responses of bean plants to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Adedipe, N O; Hofstra, G; Ormrod, D P

    1972-01-01

    Phaseolus vulgaris L. cv. Blue Lake plants were grown in sand culture at three temperatures, and fed with nutrient solution containing 1.3 or 32 mg/liter sulfur (S). Plants were fumigated twice with ozone at 50 parts per hundred million (pphm) for 2 h. Intensity of phytotoxicity was markedly lower in plants grown at the high S rate. Ozone reduced chlorophyll content of plants grown in low S at 25/20 and 30/25/sup 0/. With the high S treatment, however, ozone had no significant effect on chlorophyll content particularly at the lower temperatures. Irrespective of S nutrition, ozone had no effect on total soluble carbohydrate content. Ozone effects on plant growth depended on plant part, growth temperature, and S nutrition.

  2. Specific interactions between arbuscular mycorrhizal fungi and plant growth-promoting bacteria--as revealed by different combinations

    Energy Technology Data Exchange (ETDEWEB)

    Jaderlund, Lotta; Arthurson, Veronica; Granhall, Ulf; Jansson, Janet K.

    2008-05-15

    The interactions between two plant growth promoting rhizobacteria (PGPR), Pseudomonas fluorescens SBW25 and Paenibacillus brasilensis PB177, two arbuscular mycorrhizal (AM) fungi (Glomus mosseae and G. intraradices) and one pathogenic fungus (Microdochium nivale) were investigated on winter wheat (Triticum aestivum cultivar Tarso) in a greenhouse trial. PB177, but not SBW25, had strong inhibitory effects on M. nivale in dual culture plate assays. The results from the greenhouse experiment show very specific interactions; e.g. the two AM fungi react differently when interacting with the same bacteria on plants. G. intraradices (single inoculation or together with SBW25) increased plant dry weight on M. nivale infested plants, suggesting that the pathogenic fungus is counteracted by G. intraradices, but PB177 inhibited this positive effect. This is an example of two completely different reactions between the same AM fungus and two species of bacteria, previously known to enhance plant growth and inhibit pathogens. When searching for plant growth promoting microorganisms it is therefore important to test for the most suitable combination of plant, bacteria and fungi in order to get satisfactory plant growth benefits.

  3. [Relocation of Espeletia grandiflora (Asteraceae) plants as a strategy for enrichment of disturbed paramo areas (PNN Chingaza, Colombia)].

    Science.gov (United States)

    Rojas-Zamora, Oscar; Insuasty-Torres, Jennyfer; de Cardenas, Camilo los Angeles; Ríos, Orlando Vargas

    2013-03-01

    Ecological restoration of the Andean paramos faces several ecological barriers mainly at the phase of dispersal and establishment of native species. With the aim to contribute to the enrichment of degraded areas, different strategies have to be developed to overcome those barriers. In this work we studied the response of individuals of Espeletia grandiflora (Asteraceae) to the relocation as a strategy for ecological restoration programs. We also evaluated the effect of size of relocated individuals on their survival and development. The work was carried out in an experimental plot at 3 424m altitude in the sector "Lagunas de Siecha" of Chingaza National Park, Colombia. We relocated 200 plants that belonged to three different size classes: 5, 10 and 15cm of initial height. The following variables were registered: survival, plant height, number of living leaves and stem diameter of each individual. We also evaluated the differences between individuals in survival and development. In terms of survival the most efficient size classes corresponded to 15cm high; the survival was 85% after two years. The relative growth rates for height and stem diameter decreases with the increase in size, but the absolute increase in height did not show significant differences between the three sizes tested. Since the stem diameter was found the strongest survival predictor after two years of relocation activities, we suggest its use as a criterion for selection of relocation individuals. The relocation of individuals of E. grandiflora had a positive side effect, carrying other species that may contribute to the enrichment and restoration of degraded areas. Among these, we found species of the genus Hypericum, as well as Arcytophyllum nitidum and Calamagrostis effusa, which should be evaluated in terms of survival and development for the subsequent implementation of the relocation strategy. In this study we verified the successful relocation of individuals of E. grandiflora as a

  4. Evaluation of the plant growth-promoting activity of Pseudomonas nitroreducens in Arabidopsis thaliana and Lactuca sativa.

    Science.gov (United States)

    Trinh, Cao Son; Lee, Hyeri; Lee, Won Je; Lee, Seok Jin; Chung, Namhyun; Han, Juhyeong; Kim, Jongyun; Hong, Suk-Whan; Lee, Hojoung

    2018-06-01

    Pseudomonas nitroreducens: strain IHB B 13561 (PnIHB) enhances the growth of Arabidopsis thaliana and Lactuca sativa via the stimulation of cell development and nitrate absorption. Plant growth-promoting rhizobacteria (PGPR) enhance plant development through various mechanisms; they improve the uptake of soil resources by plants to greatly promote plant growth. Here, we used Arabidopsis thaliana seedlings and Lactuca sativa to screen the growth enhancement activities of a purified PGPR, Pseudomonas nitroreducens strain IHB B 13561 (PnIHB). When cocultivated with PnIHB, both species of plants exhibited notably improved growth, particularly in regard to biomass. Quantitative reverse transcription polymerase chain reaction analysis indicated high expression levels of the nitrate transporter genes, especially NRT2.1, which plays a major role in the high-affinity nitrate transport system in roots. Moreover, enhanced activity of the cyclin-B1 promoter was observed when wild-type 'Columbia-0' Arabidopsis seedlings were exposed to PnIHB, whereas upregulation of cyclin-B also occurred in the inoculated lettuce seedlings. Overall, these results suggest that PnIHB improves A. thaliana and L. sativa growth via specific pathways involved in the promotion of cell development and enhancement of nitrate uptake.

  5. Differential responses of onion and garlic against plant growth regulators

    International Nuclear Information System (INIS)

    Oozunidou, G.; Asif, M.; Giannakuola, A.; Iliass, A.

    2011-01-01

    The effects of Gibberellic acid-GA3, Prohexadione-Calcium, and Ethephon pre-harvest application on yield, biomass production, photosynthetic function, lipid peroxidation and quality characteristics of onion (Allium cepa L.) and garlic (Allium sativum L.) plants were investigated. Shoot length and biomass of onion and garlic, expressed either in fresh or dry weight, increased significantly under GA3, while a progressive decrease under Prohex-Ca and Ethephon occurred. Higher MDA (lipid peroxidation) values were recorded after Prohex-Ca and Ethephon supply on onion and garlic plants; it seems that GA3 treatment prevents lipid peroxidation as measured with the help of the TBARS method. Plants treated with Prohex-Ca and Ethephon revealed higher peroxidase activity compared to control and GA3 treated plants. Considering the results of MDA content and peroxidase activities it can be assumed that GA3 treated plants are slightly protected from the natural course of oxidative stress, which occurs during ageing as observed for control samples. The fluctuations of chlorophyll fluorescence parameters represent a general decline in chloroplasts function after plant growth regulators exposure, whereas in combination to the suppressed chlorophyll content, structural malformations of photo systems may also occur. The production of ascorbic acid, glucose and fructose content seems to be enhanced under GA3 in both species, while their values were depressed under Prohex-Ca and Ethephon. Overall, only GA3 supply leads to a vigorous onion and garlic growth and yield. (author)

  6. 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.

  7. Clonal growth and plant species abundance.

    Science.gov (United States)

    Herben, Tomáš; Nováková, Zuzana; Klimešová, Jitka

    2014-08-01

    Both regional and local plant abundances are driven by species' dispersal capacities and their abilities to exploit new habitats and persist there. These processes are affected by clonal growth, which is difficult to evaluate and compare across large numbers of species. This study assessed the influence of clonal reproduction on local and regional abundances of a large set of species and compared the predictive power of morphologically defined traits of clonal growth with data on actual clonal growth from a botanical garden. The role of clonal growth was compared with the effects of seed reproduction, habitat requirements and growth, proxied both by LHS (leaf-height-seed) traits and by actual performance in the botanical garden. Morphological parameters of clonal growth, actual clonal reproduction in the garden and LHS traits (leaf-specific area - height - seed mass) were used as predictors of species abundance, both regional (number of species records in the Czech Republic) and local (mean species cover in vegetation records) for 836 perennial herbaceous species. Species differences in habitat requirements were accounted for by classifying the dataset by habitat type and also by using Ellenberg indicator values as covariates. After habitat differences were accounted for, clonal growth parameters explained an important part of variation in species abundance, both at regional and at local levels. At both levels, both greater vegetative growth in cultivation and greater lateral expansion trait values were correlated with higher abundance. Seed reproduction had weaker effects, being positive at the regional level and negative at the local level. Morphologically defined traits are predictive of species abundance, and it is concluded that simultaneous investigation of several such traits can help develop hypotheses on specific processes (e.g. avoidance of self-competition, support of offspring) potentially underlying clonal growth effects on abundance. Garden

  8. The delivery of medical services in a retail shopping mall: a strategy for growth.

    Science.gov (United States)

    Hayden, K R

    1989-01-01

    The successful medical practice of the future will continually search for growth strategies. This writer believes the location of a primary care medical clinic in a retail shopping mall, with a full menu of primary services, is one strategy for growth. It is an effective method of health care delivery to a community.

  9. Mechanisms of action of plant growth promoting bacteria.

    Science.gov (United States)

    Olanrewaju, Oluwaseyi Samuel; Glick, Bernard R; Babalola, Olubukola Oluranti

    2017-10-06

    The idea of eliminating the use of fertilizers which are sometimes environmentally unsafe is slowly becoming a reality because of the emergence of microorganisms that can serve the same purpose or even do better. Depletion of soil nutrients through leaching into the waterways and causing contamination are some of the negative effects of these chemical fertilizers that prompted the need for suitable alternatives. This brings us to the idea of using microbes that can be developed for use as biological fertilizers (biofertilizers). They are environmentally friendly as they are natural living organisms. They increase crop yield and production and, in addition, in developing countries, they are less expensive compared to chemical fertilizers. These biofertilizers are typically called plant growth-promoting bacteria (PGPB). In addition to PGPB, some fungi have also been demonstrated to promote plant growth. Apart from improving crop yields, some biofertilizers also control various plant pathogens. The objective of worldwide sustainable agriculture is much more likely to be achieved through the widespread use of biofertilizers rather than chemically synthesized fertilizers. However, to realize this objective it is essential that the many mechanisms employed by PGPB first be thoroughly understood thereby allowing workers to fully harness the potentials of these microbes. The present state of our knowledge regarding the fundamental mechanisms employed by PGPB is discussed herein.

  10. Effects of the plant growth-promoting bacterium Burkholderia phytofirmans PsJN throughout the life cycle of Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    María Josefina Poupin

    Full Text Available Plant growth-promoting rhizobacteria (PGPR induce positive effects in plants, such as increased growth or reduced stress susceptibility. The mechanisms behind PGPR/plant interaction are poorly understood, as most studies have described short-term responses on plants and only a few studies have analyzed plant molecular responses under PGPR colonization. Here, we studied the effects of the PGPR bacterial model Burkholderiaphytofirmans PsJN on the whole life cycle of Arabidopsis thaliana plants. We reported that at different plant developmental points, strain PsJN can be found in the rhizosphere and also colonizing their internal tissues. In early ontogeny, strain PsJN increased several growth parameters and accelerated growth rate of the plants. Also, an Arabidopsis transcriptome analysis revealed that 408 genes showed differential expression in PsJN-inoculated plants; some of these genes are involved in stress response and hormone pathways. Specifically, genes implicated in auxin and gibberellin pathways were induced. Quantitative transcriptional analyses of selected genes in different developmental stages revealed that the beginning of these changes could be evidenced early in development, especially among the down-regulated genes. The inoculation with heat-killed bacteria provoked a more severe transcriptional response in plants, but was not able to induce plant growth-promotion. Later in ontogeny, the growth rates of inoculated plants decreased with respect to the non-inoculated group and, interestingly, the inoculation accelerated the flowering time and the appearance of senescence signs in plants; these modifications correlate with the early up-regulation of flowering control genes. Then, we show that a single inoculation with a PGPR could affect the whole life cycle of a plant, accelerating its growth rate and shortening its vegetative period, both effects relevant for most crops. Thus, these findings provide novel and interesting aspects

  11. Compost and vermicompost as nursery pot components: effects on tomato plant growth and morphology

    Energy Technology Data Exchange (ETDEWEB)

    Lazcano, C.; Arnold, J.; Tato, A.; Zaller, J. G.; Dominguez, J.

    2009-07-01

    Abstract Post transplant success after nursery stage is strongly influenced by plant morphology. Cultural practices strongly shape plant morphology, and substrate choice is one of the most determining factors. Peat is the most often used amendment in commercial potting substrates, involving the exploitation of non-renewable resources and the degradation of highly valuable peatland ecosystems and therefore alternative substrates are required. Here the feasibility of replacing peat by compost or vermicompost for the production of tomato plants in nurseries was investigated through the study of the effect of increasing proportions of these substrates (0%, 10%, 20%, 50%, 75% and 100%) in target plant growth and morphological features, indicators of adequate post-transplant growth and yield. Compost and vermicompost showed to be adequate substrates for tomato plant growth. Total replacement of peat by vermicompost was possible while doses of compost higher than 50% caused plant mortality. Low doses of compost (10 and 20%) and high doses of vermicompost produced significant increases in aerial and root biomass of the tomato plants. In addition these treatments improved significantly plant morphology (higher number of leaves and leaf area, and increased root volume and branching). The use of compost and vermicompost constitute an attractive alternative to the use of peat in plant nurseries due to the environmental benefits involved but also due to the observed improvement in plant quality. Additional key words: peat moss, plant nursery, soil-less substrate, Solanum lycopersicum L. (Author) 37 refs.

  12. Response diversity of free-floating plants to nutrient stoichiometry and temperature: growth and resting body formation

    Directory of Open Access Journals (Sweden)

    Michael J. McCann

    2016-03-01

    Full Text Available Free-floating plants, like most groups of aquatic primary producers, can become nuisance vegetation under certain conditions. On the other hand, there is substantial optimism for the applied uses of free-floating plants, such as wastewater treatment, biofuel production, and aquaculture. Therefore, understanding the species-specific responses of floating plants to abiotic conditions will inform both management decisions and the beneficial applications of these plants. I measured the responses of three floating plant species common in the northeast United States (Lemna minor, Spirodela polyrhiza, and Wolffia brasiliensis to nutrient stoichiometry (nitrogen and phosphorus and temperature in the laboratory. I also used survey data to determine the pattern of species richness of floating plants in the field and its relationship with the dominance of this group. Floating plant species exhibited unique responses to nutrient stoichiometry and temperature in the laboratory, especially under low temperatures (18 °C and low nutrient conditions (0.5 mg N L−1, 0.083 mg P L−1. The three species displayed an apparent tradeoff with different strategies of growth or dormancy. In the field, water bodies with three or more species of floating plants were not more frequently dominated by this group. The response diversity observed in the lab may not be associated with the dominance of this group in the field because it is masked by environmental variability, has a weak effect, or is only important during transient circumstances. Future research to develop applied uses of floating plants should examine response diversity across a greater range of species or clones and environmental conditions.

  13. Response diversity of free-floating plants to nutrient stoichiometry and temperature: growth and resting body formation

    Science.gov (United States)

    2016-01-01

    Free-floating plants, like most groups of aquatic primary producers, can become nuisance vegetation under certain conditions. On the other hand, there is substantial optimism for the applied uses of free-floating plants, such as wastewater treatment, biofuel production, and aquaculture. Therefore, understanding the species-specific responses of floating plants to abiotic conditions will inform both management decisions and the beneficial applications of these plants. I measured the responses of three floating plant species common in the northeast United States (Lemna minor, Spirodela polyrhiza, and Wolffia brasiliensis) to nutrient stoichiometry (nitrogen and phosphorus) and temperature in the laboratory. I also used survey data to determine the pattern of species richness of floating plants in the field and its relationship with the dominance of this group. Floating plant species exhibited unique responses to nutrient stoichiometry and temperature in the laboratory, especially under low temperatures (18 °C) and low nutrient conditions (0.5 mg N L−1, 0.083 mg P L−1). The three species displayed an apparent tradeoff with different strategies of growth or dormancy. In the field, water bodies with three or more species of floating plants were not more frequently dominated by this group. The response diversity observed in the lab may not be associated with the dominance of this group in the field because it is masked by environmental variability, has a weak effect, or is only important during transient circumstances. Future research to develop applied uses of floating plants should examine response diversity across a greater range of species or clones and environmental conditions. PMID:26989619

  14. Refuse derived soluble bio-organics enhancing tomato plant growth and productivity

    Energy Technology Data Exchange (ETDEWEB)

    Sortino, Orazio [Dipartimento di Scienze Agronomiche Agrochimiche e delle Produzioni Animali, Universita degli Studi di Catania, Via Valdisavoia 5, 95123 Catania (Italy); Dipasquale, Mauro [Dipartimento di Chimica, Universita di Torino, Via P. Giuria 7, 10125 Torino (Italy); Montoneri, Enzo, E-mail: enzo.montoneri@unito.it [Dipartimento di Chimica, Universita di Torino, Via P. Giuria 7, 10125 Torino (Italy); Tomasso, Lorenzo; Perrone, Daniele G. [Dipartimento di Chimica, Universita di Torino, Via P. Giuria 7, 10125 Torino (Italy); Vindrola, Daniela; Negre, Michele; Piccone, Giuseppe [Dipartimento di Valorizzazione e Protezione delle Risorse Agroforestali, Universita di Torino, Via L. da Vinci 44, 10095 Grugliasco (Italy)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Municipal bio-wastes are a sustainable source of bio-based products. Black-Right-Pointing-Pointer Refuse derived soluble bio-organics promote chlorophyll synthesis. Black-Right-Pointing-Pointer Refuse derived soluble bio-organics enhance plant growth and fruit ripening rate. Black-Right-Pointing-Pointer Sustainable chemistry exploiting urban refuse allows sustainable development. Black-Right-Pointing-Pointer Chemistry, agriculture and the environment benefit from biowaste technology. - Abstract: Municipal bio-refuse (CVD), containing kitchen wastes, home gardening residues and public park trimmings, was treated with alkali to yield a soluble bio-organic fraction (SBO) and an insoluble residue. These materials were characterized using elemental analysis, potentiometric titration, and 13C NMR spectroscopy, and then applied as organic fertilizers to soil for tomato greenhouse cultivation. Their performance was compared with a commercial product obtained from animal residues. Plant growth, fruit yield and quality, and soil and leaf chemical composition were the selected performance indicators. The SBO exhibited the best performance by enhancing leaf chlorophyll content, improving plant growth and fruit ripening rate and yield. No product performance-chemical composition relationship could be assessed. Solubility could be one reason for the superior performance of SBO as a tomato growth promoter. The enhancement of leaf chlorophyll content is discussed to identify a possible link with the SBO photosensitizing properties that have been demonstrated in other work, and thus with photosynthetic performance.

  15. Refuse derived soluble bio-organics enhancing tomato plant growth and productivity

    International Nuclear Information System (INIS)

    Sortino, Orazio; Dipasquale, Mauro; Montoneri, Enzo; Tomasso, Lorenzo; Perrone, Daniele G.; Vindrola, Daniela; Negre, Michele; Piccone, Giuseppe

    2012-01-01

    Highlights: ► Municipal bio-wastes are a sustainable source of bio-based products. ► Refuse derived soluble bio-organics promote chlorophyll synthesis. ► Refuse derived soluble bio-organics enhance plant growth and fruit ripening rate. ► Sustainable chemistry exploiting urban refuse allows sustainable development. ► Chemistry, agriculture and the environment benefit from biowaste technology. - Abstract: Municipal bio-refuse (CVD), containing kitchen wastes, home gardening residues and public park trimmings, was treated with alkali to yield a soluble bio-organic fraction (SBO) and an insoluble residue. These materials were characterized using elemental analysis, potentiometric titration, and 13C NMR spectroscopy, and then applied as organic fertilizers to soil for tomato greenhouse cultivation. Their performance was compared with a commercial product obtained from animal residues. Plant growth, fruit yield and quality, and soil and leaf chemical composition were the selected performance indicators. The SBO exhibited the best performance by enhancing leaf chlorophyll content, improving plant growth and fruit ripening rate and yield. No product performance-chemical composition relationship could be assessed. Solubility could be one reason for the superior performance of SBO as a tomato growth promoter. The enhancement of leaf chlorophyll content is discussed to identify a possible link with the SBO photosensitizing properties that have been demonstrated in other work, and thus with photosynthetic performance.

  16. THE RESURRECTION PLANT TRIPOGON SPICATUS (POACEAE HARBORS A DIVERSITY OF PLANT GROWTH PROMOTING BACTERIA IN NORTHEASTERN BRAZILIAN CAATINGA

    Directory of Open Access Journals (Sweden)

    Paulo Ivan Fernandes-Júnior

    2015-08-01

    Full Text Available Plant species that naturally occur in the Brazilian Caatinga(xeric shrubland adapt in several ways to these harsh conditions, and that can be exploited to increase crop production. Among the strategic adaptations to confront low water availability, desiccation tolerance stands out. Up to now, the association of those species with beneficial soil microorganisms is not well understood. The aim of this study was to characterize Tripogon spicatusdiazotrophic bacterial isolates from the Caatingabiome and evaluate their ability to promote plant growth in rice. Sixteen bacterial isolates were studied in regard to their taxonomic position by partial sequencing of the 16S rRNA gene, putative diazotrophic capacity, in vitro indole-acetic acid (IAA production and calcium phosphate solubilization, metabolism of nine different C sources in semi-solid media, tolerance to different concentrations of NaCl to pHs and intrinsic resistance to nine antibiotics. Finally, the ability of the bacterial isolates to promote plant growth was evaluated using rice (Oryza sativa as a model plant. Among the 16 isolates evaluated, eight of them were classified as Enterobacteriaceae members, related to Enterobacter andPantoeagenera. Six other bacteria were related toBacillus, and the remaining two were related toRhizobiumand Stenotrophomonas.The evaluation of total N incorporation into the semi-solid medium indicated that all the bacteria studied have putative diazotrophic capacity. Two bacteria were able to produce more IAA than that observed for the strain BR 11175Tof Herbaspirillum seropedicae.Bacterial isolates were also able to form a microaerophilic pellicle in a semi-solid medium supplemented with different NaCl concentrations up to 1.27 mol L-1. Intrinsic resistance to antibiotics and the metabolism of different C sources indicated a great variation in physiological profile. Seven isolates were able to promote rice growth, and two bacteria were more efficient than the

  17. Influence of dust on plant growth

    Energy Technology Data Exchange (ETDEWEB)

    Ershov, M F

    1959-01-01

    Further experiments were made at Kuibyshev with seedlings of Caragana aurantiaca and Prunus maackii. Some the plants were treated with a mixture of fine dust and soot at 2-2.5 g/sq m of leaf surface, and this treatment was repeated as necessary, at intervals during the growing season. Height growth of C. aurantiaca was 26.6%, and that of P. maackii 15.9% less than that of clean controls. Leaf surface area, measured shortly before fall, was 35.3% less than the controls in C. aurantiaca, and 20% less in P. maackii.

  18. Purple corn-associated rhizobacteria with potential for plant growth promotion.

    Science.gov (United States)

    Castellano-Hinojosa, A; Pérez-Tapia, V; Bedmar, E J; Santillana, N

    2018-05-01

    Purple corn (Zea mays var. purple amylaceum) is a native variety of the Peruvian Andes, cultivated at 3000 m since the pre-Inca times without N fertilization. We aimed to isolate and identify native plant growth-promoting rhizobacteria (PGPR) for future microbial-based inoculants. Eighteen strains were isolated from the rhizosphere of purple corn plants grown without N fertilization in Ayacucho (Peru). The 16S rRNA gene clustered the 18 strains into nine groups that contained species of Bacillus, Stenotrophomonas, Achromobacter, Paenibacillus, Pseudomonas and Lysinibacillus. A representative strain from each group was selected and assayed for N 2 fixation, phosphate solubilization, indole acetic and siderophore production, 1-aminocyclopropane-1-carboxylic acid deaminase activity and biocontrol abilities. Inoculation of purple corn plants with single and combined strains selected after a principal component analysis caused significant increases in root and shoot dry weight, total C and N contents of the plants. PGPRs can support growth and crop production of purple corn in the Peruvian Andes and constitute the base for microbial-based inoculants. This study enlarges our knowledge on plant-microbial interactions in high altitude mountains and provides new applications for PGPR inoculation in purple amylaceum corn, which is part of the staple diet for the native Quechua communities. © 2018 The Society for Applied Microbiology.

  19. Isolation and characterization of a plant growth-promoting rhizobacterium, Serratia sp. SY5.

    Science.gov (United States)

    Koo, So-Yeon; Cho, Kyung-Suk

    2009-11-01

    The role of plant growth-promoting rhizobacteria (PGPR) in the phytoremediation of heavy-metal-contaminated soils is important in overcoming its limitations for field application. A plant growth-promoting rhizobacterium, Serratia sp. SY5, was isolated from the rhizoplane of barnyard grass (Echinochloa crus-galli) grown in petroleum and heavy-metal-contaminated soil. This isolate has shown capacities for indole acetic acid production and siderophores synthesis. Compared with a non-inoculated control, the radicular root growth of Zea mays seedlings inoculated with SY5 can be increased by 27- or 15.4-fold in the presence of 15 mg-Cd/l or 15 mg-Cu/l, respectively. The results from hydroponic cultures showed that inoculation of Serratia sp. SY5 had a favorable influence on the initial shoot growth and biomass of Zea mays under noncontaminated conditions. However, under Cd-contaminated conditions, the inoculation of SY5 significantly increased the root biomass of Zea mays. These results indicate that Serratia sp. SY5 can serve as a promising microbial inoculant for increased plant growth in heavy-metal-contaminated soils to improve the phytoremediation efficiency.

  20. Effects of Plant Density and NPK Application on the Growth and ...

    African Journals Online (AJOL)

    Studies were conducted at Evboneka, Edo State, Nigeria in a forest zone to examine the effect of increasing plant population and NPK application on the growth and tuber yield of Dioscorea rotundata (Poir) cv “Obiaoturugo”. This study involved three trials. The first was conducted in 2010 involving five plant densities (10000 ...

  1. The effect of plant growth regulators on callus initiation in wormwood ...

    African Journals Online (AJOL)

    Studies were carried out in the Biotechnology laboratory of Plant Science Department of Ahmadu Bello University Zaria, Nigeria to study the effect of some plant growth regulators on the in vitro initiation of callus using the leaves of Chiyong variety of Artemisia annua. The explants were sterilized and incubated on Murashige ...

  2. Is there a strategy I iron uptake mechanism in maize?

    Science.gov (United States)

    Li, Suzhen; Zhou, Xiaojin; Chen, Jingtang; Chen, Rumei

    2018-04-03

    Iron is a metal micronutrient that is essential for plant growth and development. Graminaceous and nongraminaceous plants have evolved different mechanisms to mediate Fe uptake. Generally, strategy I is used by nongraminaceous plants like Arabidopsis, while graminaceous plants, such as rice, barley, and maize, are considered to use strategy II Fe uptake. Upon the functional characterization of OsIRT1 and OsIRT2 in rice, it was suggested that rice, as an exceptional graminaceous plant, utilizes both strategy I and strategy II Fe uptake systems. Similarly, ZmIRT1 and ZmZIP3 were identified as functional zinc and iron transporters in the maize genome, along with the determination of several genes encoding Zn and Fe transporters, raising the possibility that strategy I Fe uptake also occurs in maize. This mini-review integrates previous reports and recent evidence to obtain a better understanding of the mechanisms of Fe uptake in maize.

  3. Plant growth-promoting Burkholderia species isolated from annual ryegrass in Portuguese soils.

    Science.gov (United States)

    Castanheira, N; Dourado, A C; Kruz, S; Alves, P I L; Delgado-Rodríguez, A I; Pais, I; Semedo, J; Scotti-Campos, P; Sánchez, C; Borges, N; Carvalho, G; Barreto Crespo, M T; Fareleira, P

    2016-03-01

    To search for culturable Burkholderia species associated with annual ryegrass in soils from natural pastures in Portugal, with plant growth-promoting effects. Annual ryegrass seedlings were used to trap Burkholderia from two different soils in laboratory conditions. A combined approach using genomic fingerprinting and sequencing of 16S rRNA and recA genes resulted in the identification of Burkholderia strains belonging to the species Burkholderia graminis, Burkholderia fungorum and the Burkholderia cepacia complex. Most strains were able to solubilize mineral phosphate and to synthesize indole acetic acid; some of them could produce siderophores and antagonize the phytopathogenic oomycete, Phytophthora cinnamomi. A strain (G2Bd5) of B. graminis was selected for gnotobiotic plant inoculation experiments. The main effects were the stimulation of root growth and enhancement of leaf lipid synthesis and turnover. Fluorescence in situ hybridization and confocal laser microscopy evidenced that strain G2Bd5 is a rhizospheric and endophytic colonizer of annual ryegrass. This work revealed that annual ryegrass can naturally associate with members of the genus Burkholderia. A novel plant growth promoting strain of B. graminis was obtained. The novel strain belongs to the plant-associated Burkholderia cluster and is a promising candidate for exploitation as plant inoculant in field conditions. © 2015 The Society for Applied Microbiology.

  4. In-field High Throughput Phenotyping and Cotton Plant Growth Analysis Using LiDAR.

    Science.gov (United States)

    Sun, Shangpeng; Li, Changying; Paterson, Andrew H; Jiang, Yu; Xu, Rui; Robertson, Jon S; Snider, John L; Chee, Peng W

    2018-01-01

    Plant breeding programs and a wide range of plant science applications would greatly benefit from the development of in-field high throughput phenotyping technologies. In this study, a terrestrial LiDAR-based high throughput phenotyping system was developed. A 2D LiDAR was applied to scan plants from overhead in the field, and an RTK-GPS was used to provide spatial coordinates. Precise 3D models of scanned plants were reconstructed based on the LiDAR and RTK-GPS data. The ground plane of the 3D model was separated by RANSAC algorithm and a Euclidean clustering algorithm was applied to remove noise generated by weeds. After that, clean 3D surface models of cotton plants were obtained, from which three plot-level morphologic traits including canopy height, projected canopy area, and plant volume were derived. Canopy height ranging from 85th percentile to the maximum height were computed based on the histogram of the z coordinate for all measured points; projected canopy area was derived by projecting all points on a ground plane; and a Trapezoidal rule based algorithm was proposed to estimate plant volume. Results of validation experiments showed good agreement between LiDAR measurements and manual measurements for maximum canopy height, projected canopy area, and plant volume, with R 2 -values of 0.97, 0.97, and 0.98, respectively. The developed system was used to scan the whole field repeatedly over the period from 43 to 109 days after planting. Growth trends and growth rate curves for all three derived morphologic traits were established over the monitoring period for each cultivar. Overall, four different cultivars showed similar growth trends and growth rate patterns. Each cultivar continued to grow until ~88 days after planting, and from then on varied little. However, the actual values were cultivar specific. Correlation analysis between morphologic traits and final yield was conducted over the monitoring period. When considering each cultivar individually

  5. Plants, plant pathogens, and microgravity--a deadly trio

    Science.gov (United States)

    Leach, J. E.; Ryba-White, M.; Sun, Q.; Wu, C. J.; Hilaire, E.; Gartner, C.; Nedukha, O.; Kordyum, E.; Keck, M.; Leung, H.; hide

    2001-01-01

    Plants grown in spaceflight conditions are more susceptible to colonization by plant pathogens. The underlying causes for this enhanced susceptibility are not known. Possibly the formation of structural barriers and the activation of plant defense response components are impaired in spaceflight conditions. Either condition would result from altered gene expression of the plant. Because of the tools available, past studies focused on a few physiological responses or biochemical pathways. With recent advances in genomics research, new tools, including microarray technologies, are available to examine the global impact of growth in the spacecraft on the plant's gene expression profile. In ground-based studies, we have developed cDNA subtraction libraries of rice that are enriched for genes induced during pathogen infection and the defense response. Arrays of these genes are being used to dissect plant defense response pathways in a model system involving wild-type rice plants and lesion mimic mutants. The lesion mimic mutants are ideal experimental tools because they erratically develop defense response-like lesions in the absence of pathogens. The gene expression profiles from these ground-based studies will provide the molecular basis for understanding the biochemical and physiological impacts of spaceflight on plant growth, development and disease defense responses. This, in turn, will allow the development of strategies to manage plant disease for life in the space environment.

  6. Beryllium and growth. II. The effect of beryllium on plant growth

    Energy Technology Data Exchange (ETDEWEB)

    Hoagland, M B

    1952-01-01

    Experiments were undertaken to determine whether beryllium could replace magnesium in a growing organism. This was stimulated by the several known growth effects of beryllium in animals and by the fact that beryllium apparently competes with magnesium for animal alkaline phosphatases. The following findings are noted: (1) beryllium can reduce the magnesium requirement of plants by some 60% within a certain range of magnesium deficiency. (2) The residual obligatory magnesium requirements is probably accounted for by chlorophyll since beryllium appears to have no primary effect on chlorophyll or chlorophyll production. (3) The pH of the nutrient solution is critical: at acid pH's, beryllium is highly toxic, and growth increase due to beryllium only appears at initial pH's above 11.2, although this initial pH rapidly falls to neutrality during the experimental period. 22 references, 4 figures, 1 table.

  7. Review: Biotechnological strategies for conservation of rare and endangered medicinal plants

    Directory of Open Access Journals (Sweden)

    MAHENDRA KUMAR RAI

    2010-07-01

    Full Text Available Rai MK (2010 Review: Biotechnological strategies for conservation of rare and endangered medicinal plants. Biodiversitas 11: 157-166. The use of medicinal plants is as old as human civilization. The biotechnological tools play a crucial role in conservation of rare and endangered medicinal plants. The rapid depletion of plant genetic diversity has made essential to develop new in situ and ex situ conservation methods. Advances in biotechnology offer new methods for conservation of rare and endangered medicinal plants. The present review is focused on biotechnological tools like in vitro culture, micropropagation, mycorrhization, genetic transformation and development of DNA banks. These are imperative and important alternatives for the conservation of rare and endangered medicinal plants.

  8. Human Pathogens on Plants: Designing a Multidisciplinary Strategy for Research.

    Science.gov (United States)

    Fletcher, Jacqueline; Leach, Jan E; Eversole, Kellye; Tauxe, Robert

    2014-10-15

    Recent efforts to address concerns about microbial contamination of food plants and resulting foodborne illness have prompted new collaboration and interactions between the scientific communities of plant pathology and food safety. This article provides perspectives from scientists of both disciplines and presents selected research results and concepts that highlight existing and possible future synergisms for audiences of both disciplines. Plant pathology is a complex discipline that encompasses studies of the dissemination, colonization, and infection of plants by microbes such as bacteria, viruses, fungi, and oomycetes. Plant pathologists study plant diseases as well as host plant defense responses and disease management strategies with the goal of minimizing disease occurrences and impacts. Repeated outbreaks of human illness attributed to the contamination of fresh produce, nuts and seeds, and other plant-derived foods by human enteric pathogens such as Shiga toxin-producing Escherichia coli and Salmonella spp. have led some plant pathologists to broaden the application of their science in the past two decades, to address problems of human pathogens on plants (HPOPs). Food microbiology, which began with the study of microbes that spoil foods and those that are critical to produce food, now also focuses study on how foods become contaminated with pathogens and how this can be controlled or prevented. Thus, at the same time, public health researchers and food microbiologists have become more concerned about plant-microbe interactions before and after harvest. New collaborations are forming between members of the plant pathology and food safety communities, leading to enhanced research capacity and greater understanding of the issues for which research is needed. The two communities use somewhat different vocabularies and conceptual models. For example, traditional plant pathology concepts such as the disease triangle and the disease cycle can help to define

  9. Human pathogens on plants: designing a multidisciplinary strategy for research.

    Science.gov (United States)

    Fletcher, Jacqueline; Leach, Jan E; Eversole, Kellye; Tauxe, Robert

    2013-04-01

    Recent efforts to address concerns about microbial contamination of food plants and resulting foodborne illness have prompted new collaboration and interactions between the scientific communities of plant pathology and food safety. This article provides perspectives from scientists of both disciplines and presents selected research results and concepts that highlight existing and possible future synergisms for audiences of both disciplines. Plant pathology is a complex discipline that encompasses studies of the dissemination, colonization, and infection of plants by microbes such as bacteria, viruses, fungi, and oomycetes. Plant pathologists study plant diseases as well as host plant defense responses and disease management strategies with the goal of minimizing disease occurrences and impacts. Repeated outbreaks of human illness attributed to the contamination of fresh produce, nuts and seeds, and other plant-derived foods by human enteric pathogens such as Shiga toxin-producing Escherichia coli and Salmonella spp. have led some plant pathologists to broaden the application of their science in the past two decades, to address problems of human pathogens on plants (HPOPs). Food microbiology, which began with the study of microbes that spoil foods and those that are critical to produce food, now also focuses study on how foods become contaminated with pathogens and how this can be controlled or prevented. Thus, at the same time, public health researchers and food microbiologists have become more concerned about plant-microbe interactions before and after harvest. New collaborations are forming between members of the plant pathology and food safety communities, leading to enhanced research capacity and greater understanding of the issues for which research is needed. The two communities use somewhat different vocabularies and conceptual models. For example, traditional plant pathology concepts such as the disease triangle and the disease cycle can help to define

  10. Predicting plant performance under simultaneously changing environmental conditions – the interplay between temperature, light and internode growth

    Directory of Open Access Journals (Sweden)

    Katrin eKahlen

    2015-12-01

    Full Text Available Plant performance is significantly influenced by prevailing light and temperature conditions during plant growth and development. For plants exposed to natural fluctuations in abiotic environmental conditions it is however laborious and cumbersome to experimentally assign any contribution of individual environmental factors to plant responses. This study aimed at analyzing the interplay between light, temperature and internode growth based on model approaches. We extended the light-sensitive virtual plant model L-Cucumber by implementing a common Arrhenius function for appearance rates, growth rates and growth durations. For two greenhouse experiments, the temperature-sensitive model approach resulted in a precise prediction of cucumber mean internode lengths and number of internodes, as well as in accurately predicted patterns of individual internode lengths along the main stem. In addition, a system’s analysis revealed that environmental data averaged over the experimental period were not necessarily related to internode performance. Finally, the need for a species-specific parameterization of the temperature response function and related aspects in modelling temperature effects on plant development and growth is discussed.

  11. Cytokinins as key regulators in plant–microbe–insect interactions: connecting plant growth and defence

    NARCIS (Netherlands)

    Giron, D.; Frago, E.; Glevarec, G.; Pieterse, C.M.J.; Dicke, M.

    2013-01-01

    1. Plant hormones play important roles in regulating plant growth and defence by mediating developmental processes and signalling networks involved in plant responses to a wide range of parasitic and mutualistic biotic interactions. 2. Plants are known to rapidly respond to pathogen and herbivore

  12. Effect of plant growth regulators, explants type and efficient plantlet ...

    African Journals Online (AJOL)

    use

    2011-12-05

    Dec 5, 2011 ... Plant Pathology, Tissue Culture and Biotechnology Laboratory, Department of Botany,. University of ... variability in response to growth regulators. In vitro rooting ..... an adult tree Wrightia tomentosa through enhanced axillary.

  13. Plant-wide Control Strategy for Improving Produced Water Treatment

    DEFF Research Database (Denmark)

    Yang, Zhenyu; Pedersen, Simon; Løhndorf, Petar Durdevic

    2016-01-01

    This work focuses on investigation and development of an innovative Produced Water Treatment (PWT) technology for offshore oil & gas production by employing the model-based plant-wide control strategy. The key contributions lie in two folds: (i) the advanced anti-slug analysis and control...

  14. Lead tolerance in plants: strategies for phytoremediation.

    Science.gov (United States)

    Gupta, D K; Huang, H G; Corpas, F J

    2013-04-01

    Lead (Pb) is naturally occurring element whose distribution in the environment occurs because of its extensive use in paints, petrol, explosives, sludge, and industrial wastes. In plants, Pb uptake and translocation occurs, causing toxic effects resulting in decrease of biomass production. Commonly plants may prevent the toxic effect of heavy metals by induction of various celular mechanisms such as adsorption to the cell wall, compartmentation in vacuoles, enhancement of the active efflux, or induction of higher levels of metal chelates like a protein complex (metallothioneins and phytochelatins), organic (citrates), and inorganic (sulphides) complexes. Phyotochelains (PC) are synthesized from glutathione (GSH) and such synthesis is due to transpeptidation of γ-glutamyl cysteinyl dipeptides from GSH by the action of a constitutively present enzyme, PC synthase. Phytochelatin binds to Pb ions leading to sequestration of Pb ions in plants and thus serves as an important component of the detoxification mechanism in plants. At cellular level, Pb induces accumulation of reactive oxygen species (ROS), as a result of imbalanced ROS production and ROS scavenging processes by imposing oxidative stress. ROS include superoxide radical (O2(.-)), hydrogen peroxide (H2O2) and hydroxyl radical ((·)OH), which are necessary for the correct functioning of plants; however, in excess they caused damage to biomolecules, such as membrane lipids, proteins, and nucleic acids among others. To limit the detrimental impact of Pb, efficient strategies like phytoremediation are required. In this review, it will discuss recent advancement and potential application of plants for lead removal from the environment.

  15. Plant-associated fluorescent Pseudomonas from red lateritic soil: Beneficial characteristics and their impact on lettuce growth.

    Science.gov (United States)

    Maroniche, Guillermo A; Rubio, Esteban J; Consiglio, Adrián; Perticari, Alejandro

    2016-11-25

    Fluorescent Pseudomonas are ubiquitous soil bacteria that usually establish mutualistic associations with plants, promoting their growth and health by several mechanisms. This makes them interesting candidates for the development of crop bio-inoculants. In this work, we isolated phosphate-solubilizing fluorescent Pseudomonas from the rhizosphere and inner tissues of different plant species growing in red soil from Misiones, Argentina. Seven isolates displaying strong phosphate solubilization were selected for further studies. Molecular identification by rpoD genotyping indicated that they belong to different species within the P. fluorescens and P. putida phylogenetic groups. Screening for in vitro traits such as phosphate solubilization, growth regulators synthesis or degradation, motility and antagonism against phytopathogens or other bacteria, revealed a unique profile of characteristics for each strain. Their plant growth-promoting potential was assayed using lettuce as a model for inoculation under controlled and greenhouse conditions. Five of the strains increased the growth of lettuce plants. Overall, the strongest lettuce growth promoter under both conditions was strain ZME4, isolated from inner tissues of maize. No clear association between lettuce growth promotion and in vitro beneficial traits was detected. In conclusion, several phosphate solubilizing pseudomonads from red soil were isolated that display a rich array of plant growth promotion traits, thus showing a potential for the development of new inoculants.

  16. Light and Plants. A Series of Experiments Demonstrating Light Effects on Seed Germination, Plant Growth, and Plant Development.

    Science.gov (United States)

    Downs, R. J.; And Others

    A brief summary of the effects of light on plant germination, growth and development, including photoperiodism and pigment formation, introduces 18 experiments and demonstrations which illustrate aspects of these effects. Detailed procedures for each exercise are given, the expected results outlined, and possible sources of difficulty discussed.…

  17. Reciprocal Regulation of the TOR Kinase and ABA Receptor Balances Plant Growth and Stress Response.

    Science.gov (United States)

    Wang, Pengcheng; Zhao, Yang; Li, Zhongpeng; Hsu, Chuan-Chih; Liu, Xue; Fu, Liwen; Hou, Yueh-Ju; Du, Yanyan; Xie, Shaojun; Zhang, Chunguang; Gao, Jinghui; Cao, Minjie; Huang, Xiaosan; Zhu, Yingfang; Tang, Kai; Wang, Xingang; Tao, W Andy; Xiong, Yan; Zhu, Jian-Kang

    2018-01-04

    As sessile organisms, plants must adapt to variations in the environment. Environmental stress triggers various responses, including growth inhibition, mediated by the plant hormone abscisic acid (ABA). The mechanisms that integrate stress responses with growth are poorly understood. Here, we discovered that the Target of Rapamycin (TOR) kinase phosphorylates PYL ABA receptors at a conserved serine residue to prevent activation of the stress response in unstressed plants. This phosphorylation disrupts PYL association with ABA and with PP2C phosphatase effectors, leading to inactivation of SnRK2 kinases. Under stress, ABA-activated SnRK2s phosphorylate Raptor, a component of the TOR complex, triggering TOR complex dissociation and inhibition. Thus, TOR signaling represses ABA signaling and stress responses in unstressed conditions, whereas ABA signaling represses TOR signaling and growth during times of stress. Plants utilize this conserved phospho-regulatory feedback mechanism to optimize the balance of growth and stress responses. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Comparison of ALS functionality and plant growth in ALS-inhibitor susceptible and resistant Myosoton aquaticum L.

    Science.gov (United States)

    Liu, Weitang; Bai, Shuang; Jia, Sisi; Guo, Wenlei; Zhang, Lele; Li, Wei; Wang, Jinxin

    2017-10-01

    Herbicide target-site resistance mutations may cause pleiotropic effects on plant ecology and physiology. The effect of several known (Pro197Ser, Pro197Leu Pro197Ala, and Pro197Glu) target-site resistance mutations of the ALS gene on both ALS functionality and plant vegetative growth of weed Myosoton aquaticum L. (water chickweed) have been investigated here. The enzyme kinetics of ALS from four purified water chickweed populations that each homozygous for the specific target-site resistance-endowing mutations were characterized and the effect of these mutations on plant growth was assessed via relative growth rate (RGR) analysis. Plants homozygous for Pro197Ser and Pro197Leu exhibited higher extractable ALS activity than susceptible (S) plants, while all ALS mutations with no negative change in ALS kinetics. The Pro197Leu mutation increased ALS sensitivity to isoleucine and valine, and Pro197Glu mutation slightly increased ALS sensitivity to isoleucine. RGR results indicated that none of these ALS resistance mutations impose negative pleiotropic effects on relative growth rate. However, resistant (R) seeds had a lowed germination rate than S seeds. This study provides baseline information on ALS functionality and plant growth characteristics associated with ALS inhibitor resistance-endowing mutations in water chickweed. Copyright © 2017. Published by Elsevier Inc.

  19. Biomass markets. Growth strategy and challenges for French actors

    International Nuclear Information System (INIS)

    2015-01-01

    This study comprises three reports. The first one is an executive summary which focuses on the main aspects of the evolution of the activity in the biomass sector, and highlights factors of change and their strategic consequences. The second one proposes an overview of the situation of biomass French markets, analyses growth strategies adopted by actors of the biomass sector (development of new production capacities, international growth, development of strategies based on several energies, diversification of prospects, innovation and improvement of installation efficiency), and discusses the main strategic challenges on the medium term. The third report proposes a presentation of the context of French biomass markets (political, regulatory and energetic framework, energetic assessment and assessment of the waste-based sector, economic context, housing stock, and other contextual factors), a presentation of the biomass French market (data for 2005-2013, dynamics of three specific segments: solid biomass, renewable urban wastes, and biogas), and a description of the competitive landscape (economic structure, actors) and of the 15 main actors

  20. Short Communication Synergistic effect of rhizobia and plant growth promoting rhizobacteria on the growth and nodulation of lentil seedlings under axenic conditions

    Directory of Open Access Journals (Sweden)

    Muhammad Zafar-ul-Hye

    2013-05-01

    Full Text Available Plant growth promoting rhizobacteria (PGPR containing ACC-deaminase in combination with rhizobia can improve the growth and nodulation in plants by suppressing the endogenous level of ethylene. In the present study, ten strains, each of PGPR and rhizobia from the previously screened cultures were tested for their effect as co-inoculants on growth and nodulation of lentil in growth pouches under axenic conditions. Results showed that most of the combinations improved the lentil growth as compared to the un-inoculated control. Maximum increase in shoot length (1.87 fold, root length (1.97 fold and total biomass (1.98 fold over the un-inoculated control was observed in the treatment where the lentil seedlings were inoculated with the combination Z24P10. Co-inoculation also improved the nodulation in lentil and the maximum number of nodules plant-1 (24 nodules were observed in the combination Z22P10. However, there was no nodulation in few combinations. It is concluded that the co-inoculation with rhizobia and PGPR containing ACC-deaminase has improved the growth and nodulation in lentil under axenic conditions and the selected combinations may be evaluated in pot and field trials

  1. Comparative genomic analysis of four representative plant growth-promoting rhizobacteria in Pseudomonas

    Science.gov (United States)

    2013-01-01

    Background Some Pseudomonas strains function as predominant plant growth-promoting rhizobacteria (PGPR). Within this group, Pseudomonas chlororaphis and Pseudomonas fluorescens are non-pathogenic biocontrol agents, and some Pseudomonas aeruginosa and Pseudomonas stutzeri strains are PGPR. P. chlororaphis GP72 is a plant growth-promoting rhizobacterium with a fully sequenced genome. We conducted a genomic analysis comparing GP72 with three other pseudomonad PGPR: P. fluorescens Pf-5, P. aeruginosa M18, and the nitrogen-fixing strain P. stutzeri A1501. Our aim was to identify the similarities and differences among these strains using a comparative genomic approach to clarify the mechanisms of plant growth-promoting activity. Results The genome sizes of GP72, Pf-5, M18, and A1501 ranged from 4.6 to 7.1 M, and the number of protein-coding genes varied among the four species. Clusters of Orthologous Groups (COGs) analysis assigned functions to predicted proteins. The COGs distributions were similar among the four species. However, the percentage of genes encoding transposases and their inactivated derivatives (COG L) was 1.33% of the total genes with COGs classifications in A1501, 0.21% in GP72, 0.02% in Pf-5, and 0.11% in M18. A phylogenetic analysis indicated that GP72 and Pf-5 were the most closely related strains, consistent with the genome alignment results. Comparisons of predicted coding sequences (CDSs) between GP72 and Pf-5 revealed 3544 conserved genes. There were fewer conserved genes when GP72 CDSs were compared with those of A1501 and M18. Comparisons among the four Pseudomonas species revealed 603 conserved genes in GP72, illustrating common plant growth-promoting traits shared among these PGPR. Conserved genes were related to catabolism, transport of plant-derived compounds, stress resistance, and rhizosphere colonization. Some strain-specific CDSs were related to different kinds of biocontrol activities or plant growth promotion. The GP72 genome

  2. Straw gasification biochar increases plant available water capacity and plant growth in coarse sandy soil

    DEFF Research Database (Denmark)

    Hansen, Veronika; Hauggaard-Nielsen, Henrik; Petersen, Carsten Tilbæk

    Gasification biochar (GB) contains recalcitrant carbon that can contribute to soil carbon sequestration and soil quality improvement. However, the impact of GB on plant available water capacity (AWC) and plant growth in diverse soil types needs further reserach. A pot experiment with spring barley...... the characteristic low compressibility and high friction giving much better conditions for root penetration increasing yield potentials. Furthermore, risk of drought in dry periods, and nutrient losses in wet periods in coarser soil types is also reduced...

  3. Complete genome sequence of the rapeseed plant-growth promoting Serratia plymuthica strain AS9

    Energy Technology Data Exchange (ETDEWEB)

    Neupane, Saraswoti [Uppsala University, Uppsala, Sweden; Hogberg, Nils [Uppsala University, Uppsala, Sweden; Alstrom, Sadhna [Uppsala University, Uppsala, Sweden; Lucas, Susan [U.S. Department of Energy, Joint Genome Institute; Han, James [U.S. Department of Energy, Joint Genome Institute; Lapidus, Alla L. [U.S. Department of Energy, Joint Genome Institute; Cheng, Jan-Fang [U.S. Department of Energy, Joint Genome Institute; Bruce, David [Los Alamos National Laboratory (LANL); Goodwin, Lynne A. [Los Alamos National Laboratory (LANL); Pitluck, Sam [U.S. Department of Energy, Joint Genome Institute; Peters, Lin [U.S. Department of Energy, Joint Genome Institute; Ovchinnikova, Galina [U.S. Department of Energy, Joint Genome Institute; Lu, Megan [Los Alamos National Laboratory (LANL); Han, Cliff [Los Alamos National Laboratory (LANL); Detter, J. Chris [U.S. Department of Energy, Joint Genome Institute; Tapia, Roxanne [Los Alamos National Laboratory (LANL); Fiebig, Anne [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Land, Miriam L [ORNL; Hauser, Loren John [ORNL; Kyrpides, Nikos C [U.S. Department of Energy, Joint Genome Institute; Ivanova, N [U.S. Department of Energy, Joint Genome Institute; Pagani, Ioanna [U.S. Department of Energy, Joint Genome Institute; Klenk, Hans-Peter [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Woyke, Tanja [U.S. Department of Energy, Joint Genome Institute; Finlay, Roger D. [Uppsala University, Uppsala, Sweden

    2012-01-01

    Serratia plymuthica are plant-associated, plant beneficial species belonging to the family Enterobacteriaceae. The members of the genus Serratia are ubiquitous in nature and their life style varies from endophytic to free-living. S. plymuthica AS9 is of special interest for its ability to inhibit fungal pathogens of rapeseed and to promote plant growth. The genome of S. plymuthica AS9 comprises a 5,442,880 bp long circular chromosome that consists of 4,952 protein-coding genes, 87 tRNA genes and 7 rRNA operons. This genome is part of the project entitled Genomics of four rapeseed plant growth promoting bacteria with antagonistic effect on plant pathogens awarded through the 2010 DOE-JGI Community Sequencing Program (CSP2010).

  4. The effects of rare earth elements on the growth and nutrition of plants

    International Nuclear Information System (INIS)

    Diatloff, E.; Asher, C.J.; Smith, F.W.

    1998-01-01

    Full text: The rare earth elements (REEs) have many and varied uses throughout the world. However, the large scale use of REEs in agriculture is confined to China where some beneficial effects of REEs have been reported. Very little is known about the basic physiological effects of REEs on plants. Such information is essential for an understanding of how these elements may influence agricultural crop production. In this paper we summarise results of experiments rigorously conducted over 3 years to examine the effects of lanthanum (La) and cerium (Ce) on the growth and mineral nutrition of plants. Lanthanum and Ce were applied to the foliage or roots of two plant species (Corn ( Zea mays) and mungbean ( Vigna radiata)) of agricultural importance in the sub-tropical and tropical areas of the world. A commercial REE fertiliser was obtained from China, chemically analysed and found to contain mainly La and Ce nitrates. This fertiliser and comparable synthetic REE solutions were applied at the recommended rates to the leaves of corn and mungbean plants grown on a low-REE medium under well-controlled environmental conditions. Foliar application of REEs did not significantly increase the shoot dry weight of corn or mungbean. Both REE sources applied at 0.5 and 1.0% produced symptoms of foliar damage and reduced shoot dry weight in both plant species. Damage symptoms and growth reductions of plants sprayed with pure La and Ce solutions were similar to those of plants sprayed with commercial REE fertiliser. When REEs were maintained in a soluble form in nutrient solutions comparable in composition to soil solutions, concentrations of La or Ce from 1 to 16 μM (0.1 - 2 ppm) were found to be toxic to the root elongation of corn and mungbean. Subsequently, when concentrations of La or Ce below 1.5 μM (<0.2 ppm) were accurately maintained in solution, concentrations as low as 0.2 μM (0.03 ppm) were shown to be toxic to mungbean. Thus Ce at 0.2 μM (0.03 ppm) reduced the total

  5. Allocation plasticity and plant-metal partitioning: Meta-analytical perspectives in phytoremediation

    Energy Technology Data Exchange (ETDEWEB)

    Audet, Patrick [Ottawa-Carleton Institute of Biology, Department of Biology, University of Ottawa, 30 Marie-Curie Street, Ottawa, ON K1N 6N5 (Canada)], E-mail: paude086@uottawa.ca; Charest, Christiane [Ottawa-Carleton Institute of Biology, Department of Biology, University of Ottawa, 30 Marie-Curie Street, Ottawa, ON K1N 6N5 (Canada)], E-mail: ccharest@uottawa.ca

    2008-11-15

    In this meta-analysis of plant growth and metal uptake parameters, we selected 19 studies of heavy metal (HM) phytoremediation to evaluate trends of allocation plasticity and plant-metal partitioning in roots relative to shoots. We calculated indexes of biomass allocation and metal distribution for numerous metals and plant species among four families of interest for phytoremediation purposes (e.g. Brassicaceae, Fabaceae, Poaceae, and Solanaceae). We determined that plants shift their biomass and distribute metals more to roots than shoots possibly to circumvent the challenges of increasing soil-HM conditions. Although this shift is viewed as a stress-avoidance strategy complementing intrinsic stress-tolerance, our findings indicate that plants express different levels of allocation plasticity and metal partitioning depending on their overall growth strategy and status as 'fast-grower' or 'slow-grower' species. Accordingly, we propose a conceptual model of allocation plasticity and plant-metal partitioning comparing 'fast-grower' and 'slow-grower' strategies and outlining applications for remediation practices. - This meta-analysis has revealed a shift in plant biomass and metal distribution from shoots to roots possibly to protect vital functions when subjected to metal stress.

  6. Allocation plasticity and plant-metal partitioning: Meta-analytical perspectives in phytoremediation

    International Nuclear Information System (INIS)

    Audet, Patrick; Charest, Christiane

    2008-01-01

    In this meta-analysis of plant growth and metal uptake parameters, we selected 19 studies of heavy metal (HM) phytoremediation to evaluate trends of allocation plasticity and plant-metal partitioning in roots relative to shoots. We calculated indexes of biomass allocation and metal distribution for numerous metals and plant species among four families of interest for phytoremediation purposes (e.g. Brassicaceae, Fabaceae, Poaceae, and Solanaceae). We determined that plants shift their biomass and distribute metals more to roots than shoots possibly to circumvent the challenges of increasing soil-HM conditions. Although this shift is viewed as a stress-avoidance strategy complementing intrinsic stress-tolerance, our findings indicate that plants express different levels of allocation plasticity and metal partitioning depending on their overall growth strategy and status as 'fast-grower' or 'slow-grower' species. Accordingly, we propose a conceptual model of allocation plasticity and plant-metal partitioning comparing 'fast-grower' and 'slow-grower' strategies and outlining applications for remediation practices. - This meta-analysis has revealed a shift in plant biomass and metal distribution from shoots to roots possibly to protect vital functions when subjected to metal stress

  7. Early Growth of Improved Acacia mangium at Different Planting Densities

    Directory of Open Access Journals (Sweden)

    Arif Nirsatmanto

    2016-08-01

    Full Text Available Integrating tree improvement into silvicultural practices is essential in forest plantation. Concerning this fact, Acacia mangium spacing trial planted using genetically improved seed was established in West Java. This study was aimed to evaluate the impact of ages and planting density on early growth of improved seed A. mangium in the spacing trial. Improved seed from 2 seed orchards (SSO-5 and SSO-20 and a control of unimproved seed from seed stand (SS-7 were tested together in spacing 3 × 3 m and 2 × 2 m. Height, diameter, stem volume, and stand volume were observed at 3 ages. The results showed that improved seed consistently outperformed to unimproved seed. Ages were highly significant for all traits, but the significant difference varied among traits and seed sources for planting density and the interactions. High density performed better growth than low density at first year, and they were varied in subsequent ages depending on traits and seed sources. Improved seed from less intensity selection orchard was less tolerance to high density than that from high intensity selection orchard, but the tolerance was reversed in low density. Improved seed A. mangium from different level of genetic selection has responded differently in behavior to the changes of planting density.

  8. Impact of post-infiltration soil aeration at different growth stages of sub-surface trickle-irrigated tomato plants

    Science.gov (United States)

    Li, Yuan; Jia, Zong-xia; Niu, Wen-Quan; Wang, Jing-wei

    2016-07-01

    Sensitivity to low rhizosphere soil aeration may change over time and therefore plant response may also depend on different growth stages of a crop. This study quantified effects of soil aeration during 5 different periods, on growth and yield of trickle-irrigated potted single tomato plants. Irrigation levels were 0.6 to 0.7 (low level) or 0.7 to 0.8 (high level) of total water holding capacity of the pots. Soil was aerated by injecting 2.5 l of air into each pot through the drip tubing immediately after irrigation. Fresh fruit yield, above ground plant dry weight, plant height, and leaf area index response to these treatments were measured. For all these 4 response variables, means of post-infiltration aeration between 58 to 85 days after sowing were 13.4, 43.5, 13.7, and 37.7% higher than those for the non-aerated pots, respectively. The results indicated that: post-infiltration soil aeration can positively impact the yield and growth of sub-surface trickle-irrigated potted tomato plants; positive effects on plant growth can be obtained with aeration during the whole growth period or with aeration for partial periods; positive growth effects of partial periods of aeration appears to persist and result in yield benefit.

  9. Draft Genome Sequence of the Plant Growth-Promoting Cupriavidus gilardii Strain JZ4 Isolated from the Desert Plant Tribulus terrestris

    KAUST Repository

    Lafi, Feras Fawzi; Bokhari, Ameerah; Alam, Intikhab; Bajic, Vladimir B.; Hirt, Heribert; Saad, Maged

    2016-01-01

    We isolated the plant endophytic bacterium Cupriavidus gilardii strain JZ4 from the roots of the desert plant Tribulus terrestris, collected from the Jizan region, Saudi Arabia. We report here the draft genome sequence of JZ4, together with several enzymes related to plant growth-promoting activity, environmental adaption, and antifungal activity.

  10. Draft Genome Sequence of the Plant Growth-Promoting Cupriavidus gilardii Strain JZ4 Isolated from the Desert Plant Tribulus terrestris

    KAUST Repository

    Lafi, Feras Fawzi

    2016-07-28

    We isolated the plant endophytic bacterium Cupriavidus gilardii strain JZ4 from the roots of the desert plant Tribulus terrestris, collected from the Jizan region, Saudi Arabia. We report here the draft genome sequence of JZ4, together with several enzymes related to plant growth-promoting activity, environmental adaption, and antifungal activity.

  11. The role of phosphorus sources in the growth of lowland rice plant

    International Nuclear Information System (INIS)

    Sisworo, Widjang Herry

    1975-01-01

    The role of phosphorus sources in the growth of lowland rice plant was studied using P 32 -labelled superphosphate. The experiment was carried out in the glass house. Three high yielding rice varieties used in the experiment were PB 5, IR 22 and Pelita I/1. Results obtained from the experiment showed that, during early growth, seedlings in the nursery did not require any phosphorus from outside. The phosphorus needed was apparently supplied by the seeds themselves. After 10 days seedlings started using phosphorus from outside the plants. Phosphorus in the plants derived from fertilizer reached 5-12% at 16 days old and 25-40% at transplanting time depending on the varieties. Higher response to phosphorus application in the nursery was given by Pelita I/1, the phosphorus in the plants derived from fertilizer was 40% at transplanting time. The phosphorus requirement was mostly supplied by the application of phosphorus fertilizer till 20 days after transplanting but after 40 days soil-phosphorus became the main source for the plants. (author)

  12. Epiphytic and endophytic bacteria that promote growth of ethnomedicinal plants in the subtropical forests of Meghalaya, India

    Directory of Open Access Journals (Sweden)

    Fenella Mary War Nongkhlaw

    2014-12-01

    Full Text Available The present study was aimed to investigate the endophytic and epiphytic bacteria associated with selected ethnomedicinal plants from the pristine subtropical forests of Meghalaya and analyse them for plant growth promotion and antagonistic ability. This study is an attempt to explore plant associated bacteria which are beneficial to host plants, and thus aid in the conservation of ethnomedicinal plants of the studied subtropical forests, which are dwindling due to exploitation. The plant growth promotion parameters like indole acetic acid (IAA production, mineral phosphate solubilisation, acid phosphatase activity, presence of 1-aminocyclopropane-1-carboxylic acid deaminase (ACC gene, nitrogen fixation, cellulose digestion, chitin and pectin degradation were screened among the isolates. The study revealed significant differences in bacterial population not only between the epiphytic and endophytic microhabitats, but also amongst the host plants. Out of the 70 isolated plant