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Sample records for plant growth final

  1. How do plants enlarge? A balancing act. Workship on plant growth: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Boyer, J.S.

    1996-12-31

    There are signals that coordinate the development of various plant parts and thus the rates of enlargement of various plant parts and these were explored during the workshop. The participants tried to systematize their knowledge and identify over-arching concepts that need more investigation. It was generally agreed that the cell wall cannot be viewed as a passive plastic material. Synthesis and deposition take place and cause changes in the molecular architecture of the wall. Questions arise from the fact that the wall is not a constant or uniform structure but undergoes highly organized changes during enlargement while bearing a considerable load. Recent advances in signaling, biochemical analysis and ultrastructure visualization are beginning to relate to the molecular load-bearing and enzymatic activities in the wall. The participants agreed that there probably is enough information to begin developing a comprehensive model that would balance wall effects with the limitation of growth by transport, especially for water, and this could help clarify events occurring at different time scales and places. Beyond that, there seems to be a need to resolve problems of solute transport and wall behavior that are poorly understood in growing regions, leaving many promising areas for future experiments. Understanding each balancing act seems to be just the beginning.

  2. Plant Growth Regulators.

    Science.gov (United States)

    Nickell, Louis G.

    1978-01-01

    Describes the effect of "plant growth regulators" on plants, such as controlling the flowering, fruit development, plant size, and increasing crop yields. Provides a list of plant growth regulators which includes their chemical, common, and trade names, as well as their different use(s). (GA)

  3. [Plant hormones, plant growth regulators].

    Science.gov (United States)

    Végvári, György; Vidéki, Edina

    2014-06-29

    Plants seem to be rather defenceless, they are unable to do motion, have no nervous system or immune system unlike animals. Besides this, plants do have hormones, though these substances are produced not in glands. In view of their complexity they lagged behind animals, however, plant organisms show large scale integration in their structure and function. In higher plants, such as in animals, the intercellular communication is fulfilled through chemical messengers. These specific compounds in plants are called phytohormones, or in a wide sense, bioregulators. Even a small quantity of these endogenous organic compounds are able to regulate the operation, growth and development of higher plants, and keep the connection between cells, tissues and synergy between organs. Since they do not have nervous and immume systems, phytohormones play essential role in plants' life.

  4. Plant growth and cultivation.

    Science.gov (United States)

    Podar, Dorina

    2013-01-01

    There is a variety of methods used for growing plants indoor for laboratory research. In most cases plant research requires germination and growth of plants. Often, people have adapted plant cultivation protocols to the conditions and materials at hand in their own laboratory and growth facilities. Here I will provide a guide for growing some of the most frequently used plant species for research, i.e., Arabidopsis thaliana, barley (Hordeum vulgare) and rice (Oryza sativa). However, the methods presented can be used for other plant species as well, especially if they are related to the above-mentioned species. The presented methods include growing plants in soil, hydroponics, and in vitro on plates. This guide is intended as a starting point for those who are just beginning to work on any of the above-mentioned plant species. Methods presented are to be taken as suggestive and modification can be made according to the conditions existing in the host laboratory.

  5. Plant growth promoting rhizobacterium

    Science.gov (United States)

    Doktycz, Mitchel John; Pelletier, Dale A.; Schadt, Christopher Warren; Tuskan, Gerald A.; Weston, David

    2015-08-11

    The present invention is directed to the Pseudomonas fluorescens strain GM30 deposited under ATCC Accession No. PTA-13340, compositions containing the GM30 strain, and methods of using the GM30 strain to enhance plant growth and/or enhance plant resistance to pathogens.

  6. Plant growth promoting rhizobacterium

    Energy Technology Data Exchange (ETDEWEB)

    Doktycz, Mitchel John; Pelletier, Dale A.; Schadt, Christopher Warren; Tuskan, Gerald A.; Weston, David

    2015-08-11

    The present invention is directed to the Pseudomonas fluorescens strain GM30 deposited under ATCC Accession No. PTA-13340, compositions containing the GM30 strain, and methods of using the GM30 strain to enhance plant growth and/or enhance plant resistance to pathogens.

  7. 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 de

  8. 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,…

  9. 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.

  10. Plant growth-promoting bacterial endophytes.

    Science.gov (United States)

    Santoyo, Gustavo; Moreno-Hagelsieb, Gabriel; Orozco-Mosqueda, Ma del Carmen; Glick, Bernard R

    2016-02-01

    Bacterial endophytes ubiquitously colonize the internal tissues of plants, being found in nearly every plant worldwide. Some endophytes are able to promote the growth of plants. For those strains the mechanisms of plant growth-promotion known to be employed by bacterial endophytes are similar to the mechanisms used by rhizospheric bacteria, e.g., the acquisition of resources needed for plant growth and modulation of plant growth and development. Similar to rhizospheric plant growth-promoting bacteria, endophytic plant growth-promoting bacteria can act to facilitate plant growth in agriculture, horticulture and silviculture as well as in strategies for environmental cleanup (i.e., phytoremediation). Genome comparisons between bacterial endophytes and the genomes of rhizospheric plant growth-promoting bacteria are starting to unveil potential genetic factors involved in an endophytic lifestyle, which should facilitate a better understanding of the functioning of bacterial endophytes.

  11. 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.

  12. Operational development of small plant growth systems

    Science.gov (United States)

    Scheld, H. W.; Magnuson, J. W.; Sauer, R. L.

    1986-01-01

    The results of a study undertaken on the first phase of an empricial effort in the development of small plant growth chambers for production of salad type vegetables on space shuttle or space station are discussed. The overall effort is visualized as providing the underpinning of practical experience in handling of plant systems in space which will provide major support for future efforts in planning, design, and construction of plant-based (phytomechanical) systems for support of human habitation in space. The assumptions underlying the effort hold that large scale phytomechanical habitability support systems for future space stations must evolve from the simple to the complex. The highly complex final systems will be developed from the accumulated experience and data gathered from repetitive tests and trials of fragments or subsystems of the whole in an operational mode. These developing system components will, meanwhile, serve a useful operational function in providing psychological support and diversion for the crews.

  13. CHP plant Legionowo Poland - Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-12-01

    In 1997, a new Energy Law was passed in Poland. An important element of the law is that local energy planning is made obligatory. The law describes obligatory tasks and procedures for Polish municipalities related to planning and organisation of the energy sector. With the objective of supporting the Polish municipalities in their obligations according to the energy law of 1997, the project 'Energy Planning in Poland at Municipal Level - Support to Decision Makers' was launched. As part of the project, Municipal Guideline Reports have been elaborated for three model municipalities. These guidelines present the basis for the Energy Supply Plans in these municipalities. For the city of Legionowo, the following was recommended: 1. The planning processes initiated during the project should be continues/followed up, 2. Master Plan for the district heating system should be prepared, 3. The possibilities of establishment of a major natural gas-fired CHP plant of the Combined Cycle type should be investigated. The present report is the final Master Plan based on the following reports: Master Plan for Legionowo - Status Report; Master Plan for Legionowo - Hydraulic Analysis; CHP Plant Legionowo Poland - CHP Feasibility Analysis. The final Master Plan describes the status in the DH Company in Legionowo, possible improvements and an investment plan for the selected scenario. (BA)

  14. 77 FR 5913 - Endangered and Threatened Wildlife and Plants; Final Listing Determinations for Two Distinct...

    Science.gov (United States)

    2012-02-06

    ... that the Altamaha River population does exhibit exponential growth, as the Suwannee River Gulf sturgeon... Part 224 Endangered and Threatened Wildlife and Plants; Final Listing Determinations for Two Distinct... and Threatened Wildlife and Plants; Final Listing Determinations for Two Distinct Population...

  15. LED Systems Target Plant Growth

    Science.gov (United States)

    2010-01-01

    To help develop technologies for growing edible biomass (food crops) in space, Kennedy Space Center partnered with Orbital Technologies Corporation (ORBITEC), of Madison, Wisconsin, through the Small Business Innovation Research (SBIR) program. One result of this research was the High Efficiency Lighting with Integrated Adaptive Control (HELIAC) system, components of which have been incorporated into a variety of agricultural greenhouse and consumer aquarium lighting features. The new lighting systems can be adapted to a specific plant species during a specific growth stage, allowing maximum efficiency in light absorption by all available photosynthetic tissues.

  16. 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. Se

  17. 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.

  18. 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.

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

    African Journals Online (AJOL)

    STORAGESEVER

    2009-06-03

    Jun 3, 2009 ... Effect of plant growth regulators on callus induction and plant ... MS media supplemented with different levels of BA and TDZ were employed for shoot ... acre many times that of any grain crop (Burton, 1969) and are used in a ... plant regeneration from explants require the presence of .... light green. 2.50 ± ...

  20. 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.

  1. Potato crop growth as affected by nitrogen and plant density

    Directory of Open Access Journals (Sweden)

    OLIVEIRA CARLOS ALBERTO DA SILVA

    2000-01-01

    Full Text Available Growth and development variables and dry matter characteristics were studied for cultivar Snowden of potato (Solanum tuberosum L. to evaluate nitrogen and plant density influence. Disregarding ending of season plant stress, the average number of actives haulms per plant was five and it was not affected by plant spacing. However, seasonal and final number of active haulms per plant were increased at 200 kg/ha of nitrogen. Maximum stem elongation was reached quickly with double density and had the tendency to keep constant at the highest and lowest nitrogen levels after 70 days after planting. Specific stem mass defined as mass per unit stem length was established as an indirect measure of stem thickness and load capacity. Specific leaf mass position in plant was higher at upper stem leaves, increased as plant density increased and did not vary markedly over time throughout the season. The rate of leaf appearance increased drastically due to more branching caused by high nitrogen level, and increased above ground dry matter per plant. Canopy growth and development influenced main tuber yield components. The number of active tubers per haulm decreased after 60 days after planting showing that tuberization is reversible. Tuber growth functions were established allowing the estimate of dry biomass partitioning coefficients for each plant organ.

  2. Jasmonate action in plant growth and development.

    Science.gov (United States)

    Huang, Huang; Liu, Bei; Liu, Liangyu; Song, Susheng

    2017-03-01

    Phytohormones, including jasmonates (JAs), gibberellin, ethylene, abscisic acid, and auxin, integrate endogenous developmental cues with environmental signals to regulate plant growth, development, and defense. JAs are well- recognized lipid-derived stress hormones that regulate plant adaptations to biotic stresses, including herbivore attack and pathogen infection, as well as abiotic stresses, including wounding, ozone, and ultraviolet radiation. An increasing number of studies have shown that JAs also have functions in a remarkable number of plant developmental events, including primary root growth, reproductive development, and leaf senescence. Since the 1980s, details of the JA biosynthesis pathway, signaling pathway, and crosstalk during plant growth and development have been elucidated. Here, we summarize recent advances and give an updated overview of JA action and crosstalk in plant growth and development. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  3. Pinellas Plant feasibility study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-09-01

    The Pinellas Plant was built in 1956 to manufacture neutron generators, a principal component in nuclear weapons. In September 1990, the Department of Health and Rehabilitative Services (HRS) entered into an agreement with DOE to independently examine environmental monitoring data from the plant and health data from Pinellas County to determine if an epidemiological study is technically feasible to measure possible off-site health effects from ionizing radiation. Through normal plant operations, some radioactive materials have been released to the environment. Eighty percent of the total plant releases of 107,707 curies occurred in the early years of plant operation (1957--1960). The primary materials released were tritium gas, tritium oxide and krypton-85. Environmental monitoring for radioactive releases from the plant has been done regularly since 1975. The US Public Health Service Centers for Disease Control and Prevention (CDC), in assisting HRS, has determined that sufficient radiological data exist by which a dose reconstruction can be done. A dose reconstruction can provide an estimate of how much radiological exposure someone living in the vicinity of the Pinellas Plant may have suffered from environmental releases.

  4. 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.

  5. Foreign acquisition, plant survival, and employment growth

    DEFF Research Database (Denmark)

    Bandick, Roger; Görg, Holger

    2010-01-01

    endogeneity of acquisition using IV and propensity score matching approaches suggest that acquisition by foreign owners increases the lifetime of the acquired plants only if the plant was an exporter. The effect is robust to controlling for domestic acquisitions and differs between horizontal and vertical...... acquisitions. We find robust positive employment growth effects only for exporters and only if the takeover is vertical.......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...

  6. Heber geothermal demonstration power plant. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-06-01

    The binary power plant is to be a 45 MW net electrical facility deriving energy from the low salinity (14,000 ppM), moderate temperature (360/sup 0/F, 182/sup 0/C) Heber reservoir in Southern California. The optimized baseline design established for the power plant is described, and the design and optimization work that formed the basis for the baseline design is documented. The work accomplished during Phase II, Preliminary Design is also recorded, and a base provided from which detailed plant design could be continued. Related project activities in the areas of licensing, environmental, cost, and schedule are also described. The approach used to establish the Phase II optimized baseline design was to (1) review the EPRI Phase I conceptual design and feasibility studies; (2) identify current design criteria and state-of-the-art technology; and (3) develop a preliminary design optimized to the Heber site based on utiliity standards.

  7. 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 en...

  8. The role of microbial signals in plant growth and development.

    Science.gov (United States)

    Ortíz-Castro, Randy; Contreras-Cornejo, Hexon Angel; Macías-Rodríguez, Lourdes; López-Bucio, José

    2009-08-01

    Plant growth and development involves a tight coordination of the spatial and temporal organization of cell division, cell expansion and cell differentiation. Orchestration of these events requires the exchange of signaling molecules between the root and shoot, which can be affected by both biotic and abiotic factors. The interactions that occur between plants and their associated microorganisms have long been of interest, as knowledge of these processes could lead to the development of novel agricultural applications. Plants produce a wide range of organic compounds including sugars, organic acids and vitamins, which can be used as nutrients or signals by microbial populations. On the other hand, microorganisms release phytohormones, small molecules or volatile compounds, which may act directly or indirectly to activate plant immunity or regulate plant growth and morphogenesis. In this review, we focus on recent developments in the identification of signals from free-living bacteria and fungi that interact with plants in a beneficial way. Evidence has accumulated indicating that classic plant signals such as auxins and cytokinins can be produced by microorganisms to efficiently colonize the root and modulate root system architecture. Other classes of signals, including N-acyl-L-homoserine lactones, which are used by bacteria for cell-to-cell communication, can be perceived by plants to modulate gene expression, metabolism and growth. Finally, we discuss the role played by volatile organic compounds released by certain plant growth-promoting rhizobacteria in plant immunity and developmental processes. The picture that emerges is one in which plants and microbes communicate themselves through transkingdom signaling systems involving classic and novel signals.

  9. Growth and final height after liver transplantation during childhood

    NARCIS (Netherlands)

    Scheenstra, Rene; Gerver, Willem Jan; Odink, Roelof J.; van Soest, Hanneke; Peelers, Paul M. J. G.; Verkade, Henkjan J.; Sauer, Pieter J. J.

    2008-01-01

    Objective: To evaluate the effect of end-stage pediatric liver disease and liver transplantation on growth and final height. Patients and Methods: We evaluated growth at 2 years (n = 101) and 5 years (n = 63) after pediatric liver transplantation (LTx). Twenty-three children reached final height. He

  10. A continuous growth model for plant tissue

    Science.gov (United States)

    Bozorg, Behruz; Krupinski, Pawel; Jönsson, Henrik

    2016-12-01

    Morphogenesis in plants and animals involves large irreversible deformations. In plants, the response of the cell wall material to internal and external forces is determined by its mechanical properties. An appropriate model for plant tissue growth must include key features such as anisotropic and heterogeneous elasticity and cell dependent evaluation of mechanical variables such as turgor pressure, stress and strain. In addition, a growth model needs to cope with cell divisions as a necessary part of the growth process. Here we develop such a growth model, which is capable of employing not only mechanical signals but also morphogen signals for regulating growth. The model is based on a continuous equation for updating the resting configuration of the tissue. Simultaneously, material properties can be updated at a different time scale. We test the stability of our model by measuring convergence of growth results for a tissue under the same mechanical and material conditions but with different spatial discretization. The model is able to maintain a strain field in the tissue during re-meshing, which is of particular importance for modeling cell division. We confirm the accuracy of our estimations in two and three-dimensional simulations, and show that residual stresses are less prominent if strain or stress is included as input signal to growth. The approach results in a model implementation that can be used to compare different growth hypotheses, while keeping residual stresses and other mechanical variables updated and available for feeding back to the growth and material properties.

  11. 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.

  12. Plant Growth Modelling and Applications: The Increasing Importance of Plant Architecture in Growth Models

    Science.gov (United States)

    Fourcaud, Thierry; Zhang, Xiaopeng; Stokes, Alexia; Lambers, Hans; Körner, Christian

    2008-01-01

    Background Modelling plant growth allows us to test hypotheses and carry out virtual experiments concerning plant growth processes that could otherwise take years in field conditions. The visualization of growth simulations allows us to see directly and vividly the outcome of a given model and provides us with an instructive tool useful for agronomists and foresters, as well as for teaching. Functional–structural (FS) plant growth models are nowadays particularly important for integrating biological processes with environmental conditions in 3-D virtual plants, and provide the basis for more advanced research in plant sciences. Scope In this viewpoint paper, we ask the following questions. Are we modelling the correct processes that drive plant growth, and is growth driven mostly by sink or source activity? In current models, is the importance of soil resources (nutrients, water, temperature and their interaction with meristematic activity) considered adequately? Do classic models account for architectural adjustment as well as integrating the fundamental principles of development? Whilst answering these questions with the available data in the literature, we put forward the opinion that plant architecture and sink activity must be pushed to the centre of plant growth models. In natural conditions, sinks will more often drive growth than source activity, because sink activity is often controlled by finite soil resources or developmental constraints. PMA06 This viewpoint paper also serves as an introduction to this Special Issue devoted to plant growth modelling, which includes new research covering areas stretching from cell growth to biomechanics. All papers were presented at the Second International Symposium on Plant Growth Modeling, Simulation, Visualization and Applications (PMA06), held in Beijing, China, from 13–17 November, 2006. Although a large number of papers are devoted to FS models of agricultural and forest crop species, physiological and genetic

  13. International safeguards for reprocessing plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kratzer, M.; Scheinman, L.; Sievering, N.; Wonder, E.; Lipman, D.; Immerman, W.; Elliott, J.M.; Crane, F.

    1981-04-01

    Proliferation risks inherent in reprocessing show the need to employ technically effective safeguards which can detect, with a high degree of assurance and on a timely basis, the diversion of significant quantities of fissionable material. A balance must be struck between what is technically feasible and effective and what is institutionally acceptable. Purpose of this report is to examine the several technical approaches to safeguards in light of their prospective acceptability. This study defines the economic, political and institutional nature of the safeguards problem; surveys generically alternative technical approaches to international safeguards including their effectiveness and relative development; characterizes the institutional implications and uncertainties associated with the acceptance and implementation of each technical alternative; and integrates these assessments into a set of overall judgments on feasible directions for reprocessing plant safeguards systems.

  14. Plant systems/components modularization study. Final report. [PWR

    Energy Technology Data Exchange (ETDEWEB)

    1977-07-01

    The final results are summarized of a Plant Systems/Components Modularization Study based on Stone and Webster's Pressurized Water Reactor Reference Design. The program has been modified to include evaluation of the most promising areas for modular consideration based on the level of the Sundesert Project engineering design completion and the feasibility of their incorporation into the plant construction effort.

  15. Stochasticity in plant cellular growth and patterning

    Directory of Open Access Journals (Sweden)

    Heather M. Meyer

    2014-09-01

    Full Text Available Plants, along with other multicellular organisms, have evolved specialized regulatory mechanisms to achieve proper tissue growth and morphogenesis. During development, growing tissues generate specialized cell types and complex patterns necessary for establishing the function of the organ. Tissue growth is a tightly regulated process that yields highly reproducible outcomes. Nevertheless, the underlying cellular and molecular behaviors are often stochastic. Thus, how does stochasticity, together with strict genetic regulation, give rise to reproducible tissue development? This review draws examples from plants as well as other systems to explore stochasticity in plant cell division, growth, and patterning. We conclude that stochasticity is often needed to create small differences between identical cells, which are amplified and stabilized by genetic and mechanical feedback loops to begin cell differentiation. These first few differentiating cells initiate traditional patterning mechanisms to ensure regular development.

  16. 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 ......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...

  17. 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 targeted plants into those within Swedish MNEs, Swedish exporting non-MNEs, and purely domestic firms before foreign takeover. The results, controlling for possible endogeneity of the acquisition dummy using an IV and propensity score matching approach suggest that acquisition by foreign owners increases...

  18. Auxins as one of the factors of plant growth improvement by plant growth promoting rhizobacteria.

    Science.gov (United States)

    Ahmed, Ambreen; Hasnain, Shahida

    2014-01-01

    Plant growth promoting rhizobacteria (PGPR) promote plant growth by various mechanisms such as phytohormone production, enhanced water and nutrient uptake, improved nitrogen availability in the soil, production of ACC-deaminase for ethylene breakdown, phosphate solubilization, siderophore production etc. Microbial auxin production is the major factor not only responsible for strengthening the plant-microbe relationship but it also promotes plant growth and development in a positive manner. Thus, bacterial auxin production potential can be exploited for plant growth improvement that may be effective in reducing the hazardous effects of chemical fertilizers on the ecosystem used to obtain higher yields. The present review gives a better understanding of various factors and mechanisms involved in auxin production by PGPR that may be helpful in proper exploitation of these natural resources in a beneficial way.

  19. Plant growth promoting rhizobacteria (PGPR and their effect on maize

    Directory of Open Access Journals (Sweden)

    Mrkovački Nastasija

    2011-01-01

    Full Text Available Free-living soil bacteria beneficial to plant growth are usually referred to as plant growth promoting rhizobacteria (PGPR, capable of promoting plant growth by colonizing the plant root. Application of PGPR to increase the yield is limited by variability among the results obtained in the laboratory, in greenhouse and field. Rhizobacteria that promote plant growth (PGPR participate in interactions with plants (rice, wheat, maize, sugarcane, sugar beet, cotton and significantly increase their vegetative growth and yield. Apart from Azotobacter and Azospirillum, PGPR also include Acetobacter, Azoarcus and several species of Enterobacteriaceae (Klebsiella, Enterobacter, Citrobacter, and Pseudomonas. PGPR represent an alternative to plant growth enhancement chemicals.

  20. Plant growth responses to polypropylene--biocontainers

    Science.gov (United States)

    The influence of bio-fillers incorporated into polypropylene (PP) on the growth of plants was evaluated. Biocontainers were created by injection molding of PP with 25-40% by weight of Osage orange tree, Paulownia tree, coffee tree wood or dried distillers grain and 5% by weight of maleated polypropy...

  1. Effects of actinobacteria on plant disease suppression and growth promotion.

    Science.gov (United States)

    Palaniyandi, Sasikumar Arunachalam; Yang, Seung Hwan; Zhang, Lixin; Suh, Joo-Won

    2013-11-01

    Biological control and plant growth promotion by plant beneficial microbes has been viewed as an alternative to the use of chemical pesticides and fertilizers. Bacteria and fungi that are naturally associated with plants and have a beneficial effect on plant growth by the alleviation of biotic and abiotic stresses were isolated and developed into biocontrol (BCA) and plant growth-promoting agents (PGPA). Actinobacteria are a group of important plant-associated spore-forming bacteria, which have been studied for their biocontrol, plant growth promotion, and interaction with plants. This review summarizes the effects of actinobacteria as BCA, PGPA, and its beneficial associations with plants.

  2. 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.

  3. 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

  4. 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

  5. Klebsiella pneumoniae inoculants for enhancing plant growth

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. Modeling Performance of Plant Growth Regulators

    Directory of Open Access Journals (Sweden)

    W. C. Kreuser

    2017-03-01

    Full Text Available Growing degree day (GDD models can predict the performance of plant growth regulators (PGRs applied to creeping bentgrass ( L.. The goal of this letter is to describe experimental design strategies and modeling approaches to create PGR models for different PGRs, application rates, and turf species. Results from testing the models indicate that clipping yield should be measured until the growth response has diminished. This is in contrast to reapplication of a PGR at preselected intervals. During modeling, inclusion of an amplitude-dampening coefficient in the sinewave model allows the PGR effect to dissipate with time.

  7. 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.

  8. 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.

  9. 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.

  10. Plant growth conditions alter phytolith carbon

    Directory of Open Access Journals (Sweden)

    Kimberley L Gallagher

    2015-09-01

    Full Text Available Many plants, including grasses and some important human food sources, accumulate and precipitate silica in their cells to form opaline phytoliths. These phytoliths contain small amounts of organic matter (OM that are trapped during the process of silicification. Previous work has suggested that plant silica is associated with compounds such as proteins, lipids, lignin and carbohydrate complexes. It is not known whether these compounds are cellular components passively encapsulated as the cell silicifies, polymers actively involved in the precipitation process or random compounds assimilated by the plant and discarded into a glass wastebasket. Here, we used Raman spectroscopy to map the distribution of OM in phytoliths, and to analyze individual phytoliths isolated from Sorghum bicolor plants grown under different laboratory treatments. Using mapping, we showed that OM in phytoliths is distributed throughout the silica and is not related to dark spots visible in light microscopy, previously assumed to be the repository for phytolith OM. The Raman spectra exhibited common bands indicative of C-H stretching modes of general OM, and further more diagnostic bands consistent with carbohydrates, lignins and other OM. These Raman spectra exhibited variability of spectral signatures and of relative intensities between sample treatments indicating that differing growth conditions altered the phytolith carbon. This may have strong implications for understanding the mechanism of phytolith formation, and for use of phytolith carbon isotope values in dating or paleoclimate reconstruction.

  11. Plant growth conditions alter phytolith carbon.

    Science.gov (United States)

    Gallagher, Kimberley L; Alfonso-Garcia, Alba; Sanchez, Jessica; Potma, Eric O; Santos, Guaciara M

    2015-01-01

    Many plants, including grasses and some important human food sources, accumulate, and precipitate silica in their cells to form opaline phytoliths. These phytoliths contain small amounts of organic matter (OM) that are trapped during the process of silicification. Previous work has suggested that plant silica is associated with compounds such as proteins, lipids, lignin, and carbohydrate complexes. It is not known whether these compounds are cellular components passively encapsulated as the cell silicifies, polymers actively involved in the precipitation process or random compounds assimilated by the plant and discarded into a "glass wastebasket." Here, we used Raman spectroscopy to map the distribution of OM in phytoliths, and to analyze individual phytoliths isolated from Sorghum bicolor plants grown under different laboratory treatments. Using mapping, we showed that OM in phytoliths is distributed throughout the silica and is not related to dark spots visible in light microscopy, previously assumed to be the repository for phytolith OM. The Raman spectra exhibited common bands indicative of C-H stretching modes of general OM, and further more diagnostic bands consistent with carbohydrates, lignins, and other OM. These Raman spectra exhibited variability of spectral signatures and of relative intensities between sample treatments indicating that differing growth conditions altered the phytolith carbon. This may have strong implications for understanding the mechanism of phytolith formation, and for use of phytolith carbon isotope values in dating or paleoclimate reconstruction.

  12. Monoclonal Antibodies to Plant Growth Regulators

    Science.gov (United States)

    Eberle, Joachim; Arnscheidt, Angelika; Klix, Dieter; Weiler, Elmar W.

    1986-01-01

    Four high affinity monoclonal antibodies, which recognize two plant growth regulators from the cytokinin group, namely trans-zeatin riboside and dihydrozeatin riboside and their derivatives are reported. Six hybridomas were produced from three independent fusions of Balb/c spleen cells with P3-NS1-Ag 4-1 (abbreviated NS1) or X63-Ag 8.653 (X63) myeloma cells. The mice had been hyperimmunized with zeatin riboside-bovine serum albumin conjugate or dihydrozeatin riboside-bovine serum albumin conjugate for 3 months. The hybridomas secrete antibodies of the IgG 1 or IgG 2b subclass and allow the detection of femtomole amounts of the free cytokinins, their ribosides, and ribotides in plant extracts. The use of these monoclonals in radio- and enzyme-linked immunosorbent assay is also discussed. PMID:16664848

  13. Gravitational effects on plant growth hormone concentration

    Science.gov (United States)

    Bandurski, Robert S.; Schulze, Aga

    Numerous studies, particularly those of H. Dolk in the 1930's, established by means of bio-assay, that more growth hormone diffused from the lower, than from the upper side of a gravity-stimulated plant shoot. Now, using an isotope dilution assay, with 4,5,6,7 tetradeutero indole-3-acetic acid as internal standard, and selected ion monitoring-gas chromatography-mass spectrometry as the method of determination, we have confirmed Dolk's finding and established that the asymmetrically distributed hormone is, in fact, indole-3-acetic acid (IAA). This is the first physico-chemical demonstration that there is more free IAA on the lower sides of a geo-stimulated plant shoot. We have also shown that free IAA occurs primarily in the conductive vascular tissues of the shoot, whereas IAA esters predominate in the growing cortical cells. Now, using an especially sensitive gas chromatographic isotope dilution assay we have found that the hormone asymmetry also occurs in the non-vascular tissue. Currently, efforts are directed to developing isotope dilution assays, with picogram sensitivity, to determine how this asymmetry of IAA distribution is attained so as to better understand how the plant perceives the geo-stimulus.

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

    OpenAIRE

    Marius Stefan; Neculai Munteanu; Simona Dunca

    2012-01-01

    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 – e...

  15. Growth analysis of soybean plants treated with plant growth regulators Marcelo Ferraz de Campos

    Directory of Open Access Journals (Sweden)

    João Domingos Rodrigues

    2008-09-01

    Full Text Available This work aimed to verify the effect of plant growth regulators on soybean plant growth and chlorophyll content. In an experiment carried out in a greenhouse, soybean plants were cultivated (Glycine max (L. Merrill cv. BRS-184 in 10-liter pots containing soil from the arable layer, corrected and fertilized according to the soil analysis. The treatments used were: control; GA3 100mg.L-1; BAP 100mg.L-1; IBA 100mg.L-1; Stimulate® (IBA, GA3 and kinetin 20mL.L-1; mepiquat chloride 100mg.L-1 and mepiquat chloride 100mg.L-1 + BAP 100mg.L-1 + IBA 100mg.L-1. Treatments were applied three times at 30-day intervals. Six samplings were taken at 13-day intervals. The results indicated that the highest total dry weight value resulted from the application of IBA and Stimulate®, and that the application of mepiquat chloride in association with IBA and BAP reduced total dry matter production. The leaf area was smaller than the control in most treatments. The chlorophyll content and growth rate were slightly influenced by the treatments. The cytokinin treatment alone or in association with other plant growth regulators retained the chlorophyll content. RGR and NAR decreased from 99 days after sowing with the application of mepiquat chloride.

  16. Biomass Production System (BPS) Plant Growth Unit

    Science.gov (United States)

    Morrow, R. C.; Crabb, T. M.

    The Biomass Production System (BPS) was developed under the Small Business Innovative Research (SBIR) program to meet science, biotechnology and commercial plant growth needs in the Space Station era. The BPS is equivalent in size to a double middeck locker, but uses it's own custom enclosure with a slide out structure to which internal components mount. The BPS contains four internal growth chambers, each with a growing volume of more than 4 liters. Each of the growth chambers has active nutrient delivery, and independent control of temperature, humidity, lighting, and CO2 set-points. Temperature control is achieved using a thermoelectric heat exchanger system. Humidity control is achieved using a heat exchanger with a porous interface which can both humidify and dehumidify. The control software utilizes fuzzy logic for nonlinear, coupled temperature and humidity control. The fluorescent lighting system can be dimmed to provide a range of light levels. CO2 levels are controlled by injecting pure CO2 to the system based on input from an infrared gas analyzer. The unit currently does not scrub CO2, but has been designed to accept scrubber cartridges. In addition to providing environmental control, a number of features are included to facilitate science. The BPS chambers are sealed to allow CO2 and water vapor exchange measurements. The plant chambers can be removed to allow manipulation or sampling of specimens, and each chamber has gas/fluid sample ports. A video camera is provided for each chamber, and frame-grabs and complete environmental data for all science and hardware system sensors are stored on an internal hard drive. Data files can also be transferred to 3.5-inch disks using the front panel disk drive

  17. Improving the safety of LWR power plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-04-01

    This report documents the results of the Study to identify current, potential research issues and efforts for improving the safety of Light Water Reactor (LWR) power plants. This final report describes the work accomplished, the results obtained, the problem areas, and the recommended solutions. Specifically, for each of the issues identified in this report for improving the safety of LWR power plants, a description is provided in detail of the safety significance, the current status (including information sources, status of technical knowledge, problem solution and current activities), and the suggestions for further research and development. Further, the issues are ranked for action into high, medium, and low priority with respect to primarily (a) improved safety (e.g. potential reduction in public risk and occupational exposure), and secondly (b) reduction in safety-related costs (improving or maintaining level of safety with simpler systems or in a more cost-effective manner).

  18. Hydrocarbons and energy from plants: Final report, 1984-1987

    Energy Technology Data Exchange (ETDEWEB)

    Calvin, M.; Otvos, J.; Taylor, S.E.; Nemethy, E.K.; Skrukrud, C.L.; Hawkins, D.R.; Lago, R.

    1988-08-01

    Plant hydrocarbon (isoprenoid) production was investigated as an alternative source to fossil fuels. Because of their high triterpenoid (hydrocarbon) content of 4--8%, Euphorbia lathyris plants were used as a model system for this study. The structure of the E. lathyris triterpenoids was determined, and triterpenoid biosynthesis studied to better understand the metabolic regulation of isoprenoid production. Triterpenoid biosynthesis occurs in two distinct tissue types in E. lathyris plants: in the latex of the laticifer cells; and in the mesophyll cells of the leaf and stem. The latex has been fractionated by centrifugation, and it has been determined that the later steps of isoprenoid biosynthesis, the conversion of mevalonic acid to the triterpenes, are compartmentized within a vacuole. Also identified was the conversion of hydroxymethyl glutaryl-CoA to mevalonic acid, catalyzed by the enzyme Hydroxymethyl glutaryl-CoA Reductase, as a key rate limiting step in isoprenoid biosynthesis. At least two isozymes of this enzyme, one in the latex and another in the leaf plastids, have been identified. Environmental stress has been applied to plants to study changes in carbon allocation. Salinity stress caused a large decrease in growth, smaller decreases in photosynthesis, resulting in a larger allocation of carbon to both hydrocarbon and sugar production. An increase in Hydroxymethyl glutaryl-CoA Reductase activity was also observed when isoprenoid production increased. Other species where also screened for the production of hydrogen rich products such as isoprenoids and glycerides, and their hydrocarbon composition was determined.

  19. Simulated coal gas MCFC power plant system verification. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-30

    The objective of the main project is to identify the current developmental status of MCFC systems and address those technical issues that need to be resolved to move the technology from its current status to the demonstration stage in the shortest possible time. The specific objectives are separated into five major tasks as follows: Stack research; Power plant development; Test facilities development; Manufacturing facilities development; and Commercialization. This Final Report discusses the M-C power Corporation effort which is part of a general program for the development of commercial MCFC systems. This final report covers the entire subject of the Unocal 250-cell stack. Certain project activities have been funded by organizations other than DOE and are included in this report to provide a comprehensive overview of the work accomplished.

  20. Regulatory and functional interactions of plant growth regulators and plant glutathione S-transferases (GSTs).

    Science.gov (United States)

    Moons, Ann

    2005-01-01

    Plant glutathioneS-transferases (GSTs) are a heterogeneous superfamily of multifunctional proteins, grouped into six classes. The tau (GSTU) and phi (GSTF) class GSTs are the most represented ones and are plant-specific, whereas the smaller theta (GSTT) and zeta (GSTZ) classes are also found in animals. The lambda GSTs (GSTL) and the dehydroascorbate reductases (DHARs) are more distantly related. Plant GSTs perform a variety of pivotal catalytic and non-enzymatic functions in normal plant development and plant stress responses, roles that are only emerging. Catalytic functions include glutathione (GSH)-conjugation in the metabolic detoxification of herbicides and natural products. GSTs can also catalyze GSH-dependent peroxidase reactions that scavenge toxic organic hydroperoxides and protect from oxidative damage. GSTs can furthermore catalyze GSH-dependent isomerizations in endogenous metabolism, exhibit GSH-dependent thioltransferase safeguarding protein function from oxidative damage and DHAR activity functioning in redox homeostasis. Plant GSTs can also function as ligandins or binding proteins for phytohormones (i.e., auxins and cytokinins) or anthocyanins, thereby facilitating their distribution and transport. Finally, GSTs are also indirectly involved in the regulation of apoptosis and possibly also in stress signaling. Plant GST genes exhibit a diversity of expression patterns during biotic and abiotic stresses. Stress-induced plant growth regulators (i.e., jasmonic acid [JA], salicylic acid [SA], ethylene [ETH], and nitric oxide [NO] differentially activate GST gene expression. It is becoming increasingly evident that unique combinations of multiple, often interactive signaling pathways from various phytohormones and reactive oxygen species or antioxidants render the distinct transcriptional activation patterns of individual GSTs during stress. Underestimated post-transcriptional regulations of individual GSTs are becoming increasingly evident and roles

  1. Final Report for Regulation of Embryonic Development in Higher Plants

    Energy Technology Data Exchange (ETDEWEB)

    Harada, John J. [University of California, Davis

    2013-10-22

    The overall goal of the project was to define the cellular processes that underlie embryo development in plants at a mechanistic level. Our studies focused on a critical transcriptional regulator, Arabidopsis LEAFY COTYLEDON (LEC1), that is necessary and sufficient to induce processes required for embryo development. Because LEC1 regulates lipid accumulation during the maturation phase of embryo development, information about LEC1 may be useful in designing approaches to enhance biofuel production in plants. During the tenure of this project, we determined the molecular mechanisms by which LEC1 acts as a transcription factor in embryos. We also identified genes directly regulated by LEC1 and showed that many of these genes are involved in maturation processes. This information has been useful in dissecting the gene regulatory networks controlling embryo development. Finally, LEC1 is a novel isoform of a transcription factor that is conserved among eukaryotes, and LEC1 is active primarily in seeds. Therefore, we determined that the LEC1-type transcription factors first appeared in lycophytes during land plant evolution. Together, this study provides basic information that has implications for biofuel production.

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

    African Journals Online (AJOL)

    Jane

    2011-10-03

    Oct 3, 2011 ... fertilizers, are highly effective in improving root morphology and growth in safflower. .... made by Duncan's Multiple Range Test (Duncan, 1955). ... In case of cv. Saif-32 ..... Previous studies showed that plant growth promotion.

  3. Functional and Structural Optimality in Plant Growth: A Crop Modelling Case Study

    Science.gov (United States)

    Caldararu, S.; Purves, D. W.; Smith, M. J.

    2014-12-01

    Simple mechanistic models of vegetation processes are essential both to our understanding of plant behaviour and to our ability to predict future changes in vegetation. One concept that can take us closer to such models is that of plant optimality, the hypothesis that plants aim to achieve an optimal state. Conceptually, plant optimality can be either structural or functional optimality. A structural constraint would mean that plants aim to achieve a certain structural characteristic such as an allometric relationship or nutrient content that allows optimal function. A functional condition refers to plants achieving optimal functionality, in most cases by maximising carbon gain. Functional optimality conditions are applied on shorter time scales and lead to higher plasticity, making plants more adaptable to changes in their environment. In contrast, structural constraints are optimal given the specific environmental conditions that plants are adapted to and offer less flexibility. We exemplify these concepts using a simple model of crop growth. The model represents annual cycles of growth from sowing date to harvest, including both vegetative and reproductive growth and phenology. Structural constraints to growth are represented as an optimal C:N ratio in all plant organs, which drives allocation throughout the vegetative growing stage. Reproductive phenology - i.e. the onset of flowering and grain filling - is determined by a functional optimality condition in the form of maximising final seed mass, so that vegetative growth stops when the plant reaches maximum nitrogen or carbon uptake. We investigate the plants' response to variations in environmental conditions within these two optimality constraints and show that final yield is most affected by changes during vegetative growth which affect the structural constraint.

  4. New plant-growth medium for increased power output of the Plant-Microbial Fuel Cell

    NARCIS (Netherlands)

    Helder, M.; Strik, D.P.B.T.B.; Hamelers, H.V.M.; Kuijken, R.C.P.; Buisman, C.J.N.

    2012-01-01

    In a Plant-Microbial Fuel Cell anode-conditions must be created that are favorable for plant growth and electricity production. One of the major aspects in this is the composition of the plant-growth medium. Hoagland medium has been used until now, with added phosphate buffer to reduce potential

  5. Final environmental impact statement. Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    1980-10-01

    This volume contains the appendices for the Final Environmental Impact Statement for the Waste Isolation Pilot Plant (WIPP). Alternative geologic environs are considered. Salt, crystalline rock, argillaceous rock, and tuff are discussed. Studies on alternate geologic regions for the siting of WIPP are reviewed. President Carter's message to Congress on the management of radioactive wastes and the findings and recommendations of the interagency review group on nuclear waste management are included. Selection criteria for the WIPP site including geologic, hydrologic, tectonic, physicochemical compatability, and socio-economic factors are presented. A description of the waste types and the waste processing procedures are given. Methods used to calculate radiation doses from radionuclide releases during operation are presented. A complete description of the Los Medanos site, including archaeological and historic aspects is included. Environmental monitoring programs and long-term safety analysis program are described. (DMC)

  6. Phytohormonal basis for the plant growth promoting action of naturally occurring biostimulators.

    Science.gov (United States)

    Kurepin, Leonid V; Zaman, Mohammad; Pharis, Richard P

    2014-07-01

    There is increasing interest in the use of naturally occurring 'biostimulators' for enhancing the growth of agricultural and horticultural crops. Bacteria, fungi and protozoa, as well as marine algae-based seaweed extracts, can produce or contain biostimulators. The activity of biostimulators to promote plant growth is often attributed to their ability to directly or indirectly provide mineral nutrients (mostly N, but also P, S and other macro- and micro-nutrients) to plants. Alternatively, biostimulators are postulated to increase the plant's ability to assimilate these mineral nutrients, often in return for photo-assimilates (as occurs with certain bacteria and fungi associations). Although optimal growth of plants depends on the availability of adequate mineral nutritients, that growth (and also development, including reproduction) is also regulated by plant hormones (phytohormones), including gibberellins, auxins and cytokinins. This review describes and discusses the evidence that the presence or application of biostimulators also increases plant growth directly via phytohormone action and also influences the plant's ability to control its own hormone biosynthesis and homeostasis. Finally, it discusses the need for a better understanding of the role(s) that are played by the naturally occurring biostimulators associated with the plant in the crop field. It is suggested that better understanding will allow for optimal crop yield returns, since disruptions of phytohormone homeostasis in plant organs and tissues can yield either beneficial or sub-optimal outcomes.

  7. Power plant system assessment. Final report. SP-100 Program

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, R.V.; Atkins, D.F.; Bost, D.S.; Berman, B.; Clinger, D.A.; Determan, W.R.; Drucker, G.S.; Glasgow, L.E.; Hartung, J.A.; Harty, R.B.

    1983-10-31

    The purpose of this assessment was to provide system-level insights into 100-kWe-class space reactor electric systems. Using these insights, Rockwell was to select and perform conceptual design studies on a ''most attractive'' system that met the preliminary design goals and requirements of the SP-100 Program. About 4 of the 6 months were used in the selection process. The remaining 2 months were used for the system conceptual design studies. Rockwell completed these studies at the end of FY 1983. This report summarizes the results of the power plant system assessment and describes our choice for the most attractive system - the Rockwell SR-100G System (Space Reactor, 100 kWe, Growth) - a lithium-cooled UN-fueled fast reactor/Brayton turboelectric converter system.

  8. Optimization of plant mineral nutrition under growth-limiting conditions in a lunar greenhouse

    Science.gov (United States)

    Zaets, I.; Voznyuk, T.; Kovalchuk, M.; Rogutskyy, I.; Lukashov, D.; Mytrokhyn, O.; Mashkovska, S.; Foing, B.; Kozyrovska, N.

    It may be assumed that the first plants in a lunar base will play a main role in forming a protosoil of acceptable fertility needed for purposively growing second generation plants like wheat, rice, tulips, etc. The residues of the first-generation plants could be composted and transformed by microorganisms into a soil-like substrate within a loop of regenerative life support system. The lunar regolith may be used as a substrate for plant growth at the very beginning of a mission to reduce its cost. The use of microbial communities for priming plants will allow one to facilitate adaption to stressful conditions and to support the plant development under growth limiting conditions. Well-defined plant-associated bacteria were used for growing three cultivars to colonize French marigold (Tagetes patula L.) in anorthosite, a substrate of low bioavailability, analogous to a lunar rock. The consortium was composed of plant growth promoting rhizobacteria and the bacterium Paenibacillus sp. IMBG156 which stimulated seed germination, better plant development, and finally, the flowering of inoculated tagetes. In contrast, control plants grew poorly in the anorthosite and practically did not survive until flowering. Analysis of bacterial community composition showed that all species colonized plant roots, however, the rate of colonization depended on the allelopatic characteristics of marigold varieties. Bacteria of consortium were able to liberate some elements (Ca, Fe, Mn, Si, Ni, Cu, Zn) from substrate anorthosite. Plant colonization by mixed culture of bacterial strains resulted in the increase of accumulation of K, Mg, Mn by the plant and in the lowering of the level of toxic metal accumulation. It was assumed that a rationally assembled consortium of bacterial strains promoted germination of marygold seeds and supported the plant development under growth limiting conditions by means of bioleaching plant essential nutritional elements and by protecting the plant against

  9. Plant growth, assimilation,and development: a conceptual framework

    Energy Technology Data Exchange (ETDEWEB)

    Lockhart, J.A.

    1976-05-01

    Formulations are presented which describe the energy and material balances of plants in order to describe and interrelate more completely and clearly the various plant processes and physiological and ecological questions. The general relationship developed is Assimilation rate = Growth rate + Storage rate + Loss rate. This fundamental relationship is then used to examine seasonal changes, growth, and differentiation. 11 references, 4 tables.

  10. 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

  11. 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...

  12. 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

  13. Plant growth promotion in cereal and leguminous agricultural important plants: from microorganism capacities to crop production.

    Science.gov (United States)

    Pérez-Montaño, F; Alías-Villegas, C; Bellogín, R A; del Cerro, P; Espuny, M R; Jiménez-Guerrero, I; López-Baena, F J; Ollero, F J; Cubo, T

    2014-01-01

    Plant growth-promoting rhizobacteria (PGPR) are free-living bacteria which actively colonize plant roots, exerting beneficial effects on plant development. The PGPR may (i) promote the plant growth either by using their own metabolism (solubilizing phosphates, producing hormones or fixing nitrogen) or directly affecting the plant metabolism (increasing the uptake of water and minerals), enhancing root development, increasing the enzymatic activity of the plant or "helping" other beneficial microorganisms to enhance their action on the plants; (ii) or may promote the plant growth by suppressing plant pathogens. These abilities are of great agriculture importance in terms of improving soil fertility and crop yield, thus reducing the negative impact of chemical fertilizers on the environment. The progress in the last decade in using PGPR in a variety of plants (maize, rice, wheat, soybean and bean) along with their mechanism of action are summarized and discussed here. Copyright © 2013 Elsevier GmbH. All rights reserved.

  14. Plant growth-promoting bacteria as inoculants in agricultural soils.

    Science.gov (United States)

    Souza, Rocheli de; Ambrosini, Adriana; Passaglia, Luciane M P

    2015-12-01

    Plant-microbe interactions in the rhizosphere are the determinants of plant health, productivity and soil fertility. Plant growth-promoting bacteria (PGPB) are bacteria that can enhance plant growth and protect plants from disease and abiotic stresses through a wide variety of mechanisms; those that establish close associations with plants, such as the endophytes, could be more successful in plant growth promotion. Several important bacterial characteristics, such as biological nitrogen fixation, phosphate solubilization, ACC deaminase activity, and production of siderophores and phytohormones, can be assessed as plant growth promotion (PGP) traits. Bacterial inoculants can contribute to increase agronomic efficiency by reducing production costs and environmental pollution, once the use of chemical fertilizers can be reduced or eliminated if the inoculants are efficient. For bacterial inoculants to obtain success in improving plant growth and productivity, several processes involved can influence the efficiency of inoculation, as for example the exudation by plant roots, the bacterial colonization in the roots, and soil health. This review presents an overview of the importance of soil-plant-microbe interactions to the development of efficient inoculants, once PGPB are extensively studied microorganisms, representing a very diverse group of easily accessible beneficial bacteria.

  15. Plant growth-promoting bacteria as inoculants in agricultural soils

    Directory of Open Access Journals (Sweden)

    Rocheli de Souza

    2015-01-01

    Full Text Available AbstractPlant-microbe interactions in the rhizosphere are the determinants of plant health, productivity and soil fertility. Plant growth-promoting bacteria (PGPB are bacteria that can enhance plant growth and protect plants from disease and abiotic stresses through a wide variety of mechanisms; those that establish close associations with plants, such as the endophytes, could be more successful in plant growth promotion. Several important bacterial characteristics, such as biological nitrogen fixation, phosphate solubilization, ACC deaminase activity, and production of siderophores and phytohormones, can be assessed as plant growth promotion (PGP traits. Bacterial inoculants can contribute to increase agronomic efficiency by reducing production costs and environmental pollution, once the use of chemical fertilizers can be reduced or eliminated if the inoculants are efficient. For bacterial inoculants to obtain success in improving plant growth and productivity, several processes involved can influence the efficiency of inoculation, as for example the exudation by plant roots, the bacterial colonization in the roots, and soil health. This review presents an overview of the importance of soil-plant-microbe interactions to the development of efficient inoculants, once PGPB are extensively studied microorganisms, representing a very diverse group of easily accessible beneficial bacteria.

  16. The regulation of plant growth by the circadian clock.

    Science.gov (United States)

    Farré, E M

    2012-05-01

    Circadian regulated changes in growth rates have been observed in numerous plants as well as in unicellular and multicellular algae. The circadian clock regulates a multitude of factors that affect growth in plants, such as water and carbon availability and light and hormone signalling pathways. The combination of high-resolution growth rate analyses with mutant and biochemical analysis is helping us elucidate the time-dependent interactions between these factors and discover the molecular mechanisms involved. At the molecular level, growth in plants is modulated through a complex regulatory network, in which the circadian clock acts at multiple levels. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  17. Control of the actin cytoskeleton in plant cell growth

    NARCIS (Netherlands)

    Hussey, P.J.; Ketelaar, M.J.; Deeks, M.J.

    2006-01-01

    Plant cells grow through increases in volume and cell wall surface area. The mature morphology of a plant cell is a product of the differential rates of expansion between neighboring zones of the cell wall during this process. Filamentous actin arrays are associated with plant cell growth, and the a

  18. Induced systemic resistance by plant growth-promoting rhizobacteria

    NARCIS (Netherlands)

    Pieterse, C.M.J.; Pelt, J.A. van; Verhagen, B.W.M.; Ton, J.; Wees, A.C.M. van; Léon-Kloosterziel, K.M.; Loon, L.C. van

    2003-01-01

    Rhizobacteria are present in large numbers on the root surface, where plant exudates and lysates provide nutrients. Selected strains of beneficial, plant growth-promoting rhizobacteria (PGPR) trigger a plant-mediated induced systemic resistance (ISR) response that is effective against a broad spectr

  19. Versatile roles of plastids in plant growth and development.

    Science.gov (United States)

    Inaba, Takehito; Ito-Inaba, Yasuko

    2010-11-01

    Plastids, found in plants and some parasites, are of endosymbiotic origin. The best-characterized plastid is the plant cell chloroplast. Plastids provide essential metabolic and signaling functions, such as the photosynthetic process in chloroplasts. However, the role of plastids is not limited to production of metabolites. Plastids affect numerous aspects of plant growth and development through biogenesis, varying functional states and metabolic activities. Examples include, but are not limited to, embryogenesis, leaf development, gravitropism, temperature response and plant-microbe interactions. In this review, we summarize the versatile roles of plastids in plant growth and development.

  20. Direct fuel cell power plants: the final steps to commercialization

    Science.gov (United States)

    Glenn, Donald R.

    Since the last paper presented at the Second Grove Fuel Cell Symposium, the Energy Research Corporation (ERC) has established two commercial subsidiaries, become a publically-held firm, expanded its facilities and has moved the direct fuel cell (DFC) technology and systems significantly closer to commercial readiness. The subsidiaries, the Fuel Cell Engineering Corporation (FCE) and Fuel Cell Manufacturing Corporation (FCMC) are perfecting their respective roles in the company's strategy to commercialize its DFC technology. FCE is the prime contractor for the Santa Clara Demonstration and is establishing the needed marketing, sales, engineering, and servicing functions. FCMC in addition to producing the stacks and stack modules for the Santa Clara demonstration plant is now upgrading its production capability and product yields, and retooling for the final stack scale-up for the commercial unit. ERC has built and operated the tallest and largest capacities-to-date carbonate fuel cell stacks as well as numerous short stacks. While most of these units were tested at ERC's Danbury, Connecticut (USA) R&D Center, others have been evaluated at other domestic and overseas facilities using a variety of fuels. ERC has supplied stacks to Elkraft and MTU for tests with natural gas, and RWE in Germany where coal-derived gas were used. Additional stack test activities have been performed by MELCO and Sanyo in Japan. Information from some of these activities is protected by ERC's license arrangements with these firms. However, permission for limited data releases will be requested to provide the Grove Conference with up-to-date results. Arguably the most dramatic demonstration of carbonate fuel cells in the utility-scale, 2 MW power plant demonstration unit, located in the City of Santa Clara, California. Construction of the unit's balance-of-plant (BOP) has been completed and the installed equipment has been operationally checked. Two of the four DFC stack sub-modules, each

  1. Plant growth regulation of Bt-cotton through Bacillus species

    OpenAIRE

    Pindi, Pavan Kumar; Sultana, Tasleem; Vootla, Praveen Kumar

    2013-01-01

    Deccan plateau in India periodically experiences droughts due to irregular rain fall and the soil in many parts of the region is considered to be poor for farming. Plant growth promoting rhizobacteria are originally defined as root-colonizing bacteria, i.e., Bacillus that cause either plant growth promotion or biological control of plant diseases. The study aims at the isolation of novel Bacillus species and to assess the biotechnological potential of the novel species as a biofertilizer, wit...

  2. 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

    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. Plants are known to rapidly respond to pathogen and herbivore attack b

  3. 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

    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. Plants are known to rapidly respond to pathogen and herbivore attack b

  4. Assessment of plant-derived hydrocarbons. Final report

    Energy Technology Data Exchange (ETDEWEB)

    McFadden, K.; Nelson, S.H.

    1981-09-30

    A number of hydrocarbon producing plants are evaluated as possible sources of rubber, liquid fuels, and industrial lubricants. The plants considered are Euphorbia lathyris or gopher plant, milkweeds, guayule, rabbit brush, jojoba, and meadow foam. (ACR)

  5. Gibberellins - a multifaceted hormone in plant growth regulatory network.

    Science.gov (United States)

    Gantait, Saikat; Sinniah, Uma Rani; Ali, Md Nasim; Sahu, Narayan Chandra

    2015-01-01

    Plants tend to acclimatize to unfavourable environs by integrating growth and development to environmentally activated signals. Phytohormones strongly regulate convergent developmental and stress adaptive procedures and synchronize cellular reaction to the exogenous and endogenous conditions within the adaptive signaling networks. Gibberellins (GA), a group of tetracyclic diterpenoids, being vital regulators of plant growth, are accountable for regulating several aspects of growth and development of higher plants. If the element of reproduction is considered as an absolute requisite then for a majority of the higher plants GA signaling is simply indispensable. Latest reports have revealed unique conflicting roles of GA and other phytohormones in amalgamating growth and development in plants through environmental signaling. Numerous physiological researches have detailed substantial crosstalk between GA and other hormones like abscisic acid, auxin, cytokinin, and jasmonic acid. In this review, a number of explanations and clarifications for this discrepancy are explored based on the crosstalk among GA and other phytohormones.

  6. [Influence endophytic bacteria to promote plants growth in stress conditions].

    Science.gov (United States)

    Napora, Anna; Kacprzak, Małgorzata; Nowak, Kamil; Grobelak, Anna

    2015-01-01

    The growth of plants under stress conditions is often assisted by microorganisms colonizing the rhizosphere (the root zone of the highest microbial activity). One of the most important bacterial groups to encourage the growth of plants (PGPB) are endophytes. These microorganisms penetrate living cells of plants and there they lead the microbiological activity as endosymbionts. These microorganisms can effectively promote the growth of plants under stress conditions and stimulate biochemical activities: nitrogen fixation, production of growth hormones (auxins, cytokinins and gibberellins), reduction of the high concentration of ethylene as well as facilitation of the collection plant minerals and water. This paper is an attempt to summarize the current state of knowledge about the biochemical activity of bacterial endophytes.

  7. Changes in alpine plant growth under future climate conditions

    Directory of Open Access Journals (Sweden)

    A. Rammig

    2010-06-01

    Full Text Available Alpine shrub- and grasslands are shaped by extreme climatic conditions such as a long-lasting snow cover and a short vegetation period. Such ecosystems are expected to be highly sensitive to global environmental change. Prolonged growing seasons and shifts in temperature and precipitation are likely to affect plant phenology and growth. In a unique experiment, climatology and plant growth was monitored for almost a decade at 17 snow meteorological stations in different alpine regions along the Swiss Alps. Regression analyses revealed highly significant correlations between mean air temperature in May/June and snow melt out, onset of plant growth, and plant height. These correlations were used to project plant growth phenology for future climate conditions based on the gridded output of a set of regional climate models runs. Melt out and onset of growth were projected to occur on average 17 days earlier by the end of the century than in the control period from 1971–2000 under the future climate conditions of the low resolution climate model ensemble. Plant height and biomass production were expected to increase by 77% and 45%, respectively. The earlier melt out and onset of growth will probably cause a considerable shift towards higher growing plants and thus increased biomass. Our results represent the first quantitative and spatially explicit estimates of climate change impacts on future growing season length and the respective productivity of alpine plant communities in the Swiss Alps.

  8. Diesel power plants based on biomass gasification. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kurkela, E.; Staahlberg, P.; Solantausta, Y.; Wilen, C.

    1996-12-31

    The aim of the project was to assess the competitiveness and market potential of small-scale power plant concepts based on biomass gasification and on diesel/gas engines, and to study the effect of process parameters on the efficiency of the circulating fluidized-bed gasifier and on the formation of tarry impurities. Alternative diesel/gas engine power plant concepts based on gasification in scale 6-50 MW{sub e} were assessed. In the basic version, where the electricity is generated only by the a diesel/gas engine, the efficiency level of 37 % is achieved in power generation. When steam cycle is added to the process the efficiency of power generation increases to 44-48 %. The efficiencies achieved in the process are very high compared with those of biomass power plant processes on a commercial level or under development. The most significant potential of biomass-based power generation is made up by wastes of sugar industries in south and Central America and in Asia. There are also very extensive growth potentials of bioenergy use in the NAFTA countries (USA, Canada and Mexico) and in Europe. In Europe, the bioenergy use is expected to grow most sharply in Italy, Spain, Germany and Poland. Carbon conversion obtained in the gasifier was in the range of 99.0-99.9 % for sawdust and 96-98 % for forest residue chips. The tar content of the product gas 10-15 g/m- m{sup 3}{sub n}, for sawdust in the gasification temperature of 830-930 deg C and with sand as circulating fluid-bed. When dolomite was used as circulating fluid-bed, the tar contents were 2-3 g/m{sup 3}{sub n} at as low temperatures as 880-890 deg C. The tar content of gas can be reduced sharply by phasing of gasification air and by using catalytic circulating fluid-bed material Bioenergy Research Programme; LIEKKI 2 Research Programme. 26 refs., 40 figs.

  9. Plant growth regulators enhance gold uptake in Brassica juncea.

    Science.gov (United States)

    Kulkarni, Manoj G; Stirk, Wendy A; Southway, Colin; Papenfus, Heino B; Swart, Pierre A; Lux, Alexander; Vaculík, Marek; Martinka, Michal; Van Staden, Johannes

    2013-01-01

    The use of plant growth regulators is well established and they are used in many fields of plant science for enhancing growth. Brassica juncea plants were treated with 2.5, 5.0 and 7.5 microM auxin indole-3-butyric acid (IBA), which promotes rooting. The IBA-treated plants were also sprayed with 100 microM gibberellic acid (GA3) and kinetin (Kin) to increase leaf-foliage. Gold (I) chloride (AuCl) was added to the growth medium of plants to achieve required gold concentration. The solubilizing agent ammonium thiocyanate (1 g kg(-1)) (commonly used in mining industries to solubilize gold) was added to the nutrient solution after six weeks of growth and, two weeks later, plants were harvested. Plant growth regulators improved shoot and root dry biomass of B. juncea plants. Inductively Coupled Plasma Optical Emission Spectrometry analysis showed the highest Au uptake for plants treated with 5.0 microM IBA. The average recovery of Au with this treatment was significantly greater than the control treatment by 45.8 mg kg(-1) (155.7%). The other IBA concentrations (2.5 and 7.5 microM) also showed a significant increase in Au uptake compared to the control plants by 14.7 mg kg(-1) (50%) and 42.5 mg kg(-1) (144.5%) respectively. A similar trend of Au accumulation was recorded in the roots of B. juncea plants. This study conducted in solution culture suggests that plant growth regulators can play a significant role in improving phytoextraction of Au.

  10. 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.

  11. 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.

  12. Tubular Membrane Plant-Growth Unit

    Science.gov (United States)

    Dreschel, Thomas W.

    1992-01-01

    Hydroponic system controls nutrient solution for growing crops in space. Pump draws nutrient solution along inside of tubular membrane in pipe from reservoir, maintaining negative pressure in pipe. Roots of plants in slot extract nutrient through membrane within pipe. Crop plants such as wheat, rice, lettuce, tomatoes, soybeans, and beans grown successfully with system.

  13. Plant growth promotion by Pseudomonas fluorescens

    NARCIS (Netherlands)

    Cheng, X.

    2016-01-01

    Pseudomonas fluorescens is a Gram-negative rod shaped bacterium that has a versatile metabolism and is widely spread in soil and water. P. fluorescens strain SBW25 (Pf.SBW25) is a well-known model strain to study bacterial evolution, plant colonization and biocontrol of plant diseases. It produces t

  14. 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.

  15. Regeneration of Dioscorea floribunda plants from cryopreserved encapsulated shoot tips: effect of plant growth regulators.

    Science.gov (United States)

    Mandal, B B; Ahuja-Ghosh, Sangeeta

    2007-01-01

    The encapsulation-dehydration protocol for the cryopreservation of in vitro shoot tips of Dioscorea floribunda was optimized. Maximum survival of 87% was obtained when overnight pretreatment with 0.3 M sucrose was followed by encapsulation, preculture in 0.75 M sucrose for 4 d, dehydration in a laminar air flow for 5.5 h, quenching in liquid nitrogen and thawing at 40 degrees C. During recovery growth, 29% shoot formation was obtained when cryopreserved shoot tips were initially cultured for 25 d on a medium with 1.5 mg per liter (-1) BAP, 0.2 mg per liter(-1) NAA and 0.2 mg per liter(-1) GA3 followed by culturing for 15 d on a medium with reduced BAP (1 mg per liter(-1)) but increased NAA (0.5 mg per liter(-1)) and GA3 (0.3 mg per liter(-1)). Finally, transfer on to a medium with further reduced doses of BAP (0.05 mg per liter(-1)) and NAA (0.15 mg per liter(-1)) but without GA3 stimulated production of fully grown plantlets. All plants regenerated without callus formation. Modification of post-thaw culture media with plant growth regulators was essential for regrowth of shoot tips to plantlets.

  16. Plant growth-promoting rhizobacteria and root system functioning

    Directory of Open Access Journals (Sweden)

    Jordan eVacheron

    2013-09-01

    Full Text Available The rhizosphere supports the development and activity of a huge and diversified microbial community, including microorganisms capable to promote plant growth. Among the latter, Plant Growth-Promoting Rhizobacteria (PGPR colonize roots of monocots and dicots, and enhance plant growth by direct and indirect mechanisms. Modification of root system architecture by PGPR implicates the production of phytohormones and other signals that lead, mostly, to enhanced lateral root branching and development of root hairs. PGPR also modify root functioning, improve plant nutrition and influence the physiology of the whole plant. Recent results provided first clues as to how PGPR signals could trigger these plant responses. Whether local and/or systemic, the plant molecular pathways involved remain often unknown. From an ecological point of view, it emerged that PGPR form coherent functional groups, whose rhizosphere ecology is influenced by a myriad of abiotic and biotic factors in natural and agricultural soils, and these factors can in turn modulate PGPR effects on roots. In this paper, we address novel knowledge and gaps on PGPR modes of action and signals, and highlight recent progress on the links between plant morphological and physiological effects induced by PGPR. We also show the importance of taking into account the size, diversity and gene expression patterns of PGPR assemblages in the rhizosphere to better understand their impact on plant growth and functioning. Integrating mechanistic and ecological knowledge on PGPR populations in soil will be a prerequisite to develop novel management strategies for sustainable agriculture.

  17. Plant hormone cross-talk: the pivot of root growth.

    Science.gov (United States)

    Pacifici, Elena; Polverari, Laura; Sabatini, Sabrina

    2015-02-01

    Root indeterminate growth and its outstanding ability to produce new tissues continuously make this organ a highly dynamic structure able to respond promptly to external environmental stimuli. Developmental processes therefore need to be finely tuned, and hormonal cross-talk plays a pivotal role in the regulation of root growth. In contrast to what happens in animals, plant development is a post-embryonic process. A pool of stem cells, placed in a niche at the apex of the meristem, is a source of self-renewing cells that provides cells for tissue formation. During the first days post-germination, the meristem reaches its final size as a result of a balance between cell division and cell differentiation. A complex network of interactions between hormonal pathways co-ordinates such developmental inputs. In recent years, by means of molecular and computational approaches, many efforts have been made aiming to define the molecular components of these networks. In this review, we focus our attention on the molecular mechanisms at the basis of hormone cross-talk during root meristem size determination. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  18. 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.

  19. Clinostat Delivers Power To Plant-Growth Cabinets

    Science.gov (United States)

    Bushong, Wilton E.; Fox, Ronald C.; Brown, Christopher S.; Biro, Ronald R.; Dreshel, Thomas W.

    1993-01-01

    Clinostat rotates coaxial pair of plant-growth cabinets about horizontal axis while supplying cabinets with electric power for built-in computers, lamps, fans, and auxiliary equipment, such as nutrient pumps. Each cabinet self-contained unit for growing plants in controlled environment. By rotating cabinets and contents about horizontal axis, scientists simulate and study some of effects of microgravity on growth of plants. Clinostat includes vertical aluminum mounting bracket on horizontal aluminum base. Bearings on bracket hold shaft with V-belt pulley. At each end of shaft, circular plate holds frame mount for cabinet. Mounting plates also used to hold transparent sealed growth chambers described in article, "Sealed Plant-Growth Chamber For Clinostat" (KSC-11538).

  20. 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.

  1. Next generation geothermal power plants. Draft final report

    Energy Technology Data Exchange (ETDEWEB)

    Brugman, John; Hattar, John; Nichols, Kenneth; Esaki, Yuri

    1994-12-01

    The goal of this project is to develop concepts for the next generation geothermal power plant(s) (NGGPP). This plant, compared to existing plants, will generate power for a lower levelized cost and will be more competitive with fossil fuel fired power plants. The NGGPP will utilize geothermal resources efficiently and will be equipped with contingencies to mitigate the risk of reservoir performance. The NGGPP design will attempt to minimize emission of pollutants and consumption of surface water and/or geothermal fluids for cooling service.

  2. Plant Growth and Morphogenesis under Different Gravity Conditions: Relevance to Plant Life in Space.

    Science.gov (United States)

    Hoson, Takayuki

    2014-05-16

    The growth and morphogenesis of plants are entirely dependent on the gravitational acceleration of earth. Under microgravity conditions in space, these processes are greatly modified. Recent space experiments, in combination with ground-based studies, have shown that elongation growth is stimulated and lateral expansion suppressed in various shoot organs and roots under microgravity conditions. Plant organs also show automorphogenesis in space, which consists of altered growth direction and spontaneous curvature in the dorsiventral (back and front) directions. Changes in cell wall properties are responsible for these modifications of growth and morphogenesis under microgravity conditions. Plants live in space with interesting new sizes and forms.

  3. Plant Growth and Morphogenesis under Different Gravity Conditions: Relevance to Plant Life in Space

    Directory of Open Access Journals (Sweden)

    Takayuki Hoson

    2014-05-01

    Full Text Available The growth and morphogenesis of plants are entirely dependent on the gravitational acceleration of earth. Under microgravity conditions in space, these processes are greatly modified. Recent space experiments, in combination with ground-based studies, have shown that elongation growth is stimulated and lateral expansion suppressed in various shoot organs and roots under microgravity conditions. Plant organs also show automorphogenesis in space, which consists of altered growth direction and spontaneous curvature in the dorsiventral (back and front directions. Changes in cell wall properties are responsible for these modifications of growth and morphogenesis under microgravity conditions. Plants live in space with interesting new sizes and forms.

  4. Plant Growth Models Using Artificial Neural Networks

    Science.gov (United States)

    Bubenheim, David

    1997-01-01

    In this paper, we descrive our motivation and approach to devloping models and the neural network architecture. Initial use of the artificial neural network for modeling the single plant process of transpiration is presented.

  5. Magnetic field effects on plant growth, development and evolution

    Directory of Open Access Journals (Sweden)

    Massimo E. Maffei

    2014-09-01

    Full Text Available The geomagnetic field (GMF is a natural component of our environment. Plants, which are known to sense different wavelengths of light, respond to gravity, react to touch and electrical signaling, cannot escape the effect of GMF. While phototropism, gravitropism, and tigmotropism have been thoroughly studied, the impact of GMF on plant growth and development is not well understood. This review describes the effects of altering MF conditions on plants by considering plant responses to MF values either lower or higher than those of the GMF. The possible role of GMF on plant evolution and the nature of the magnetoreceptor is also discussed.

  6. Final Report: RPP-WTP Semi-Integrated Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    Duignan, M. R.; Adamson, D. J.; Calloway, T. B.; Fowley, M. D.; Qureshi, Z. H.; Steimke, J. L.; Williams, M. R.; Zamecnik, J. R.

    2005-06-01

    In August 2004 the last of the SIPP task testing ended--a task that formally began with the issuance of the RPP-WTP Test Specification in June 2003. The planning for the task was a major effort in itself and culminated with the input of all stakeholders, DOE, Bechtel National, Inc., Washington Group International, in October 2003 at Hanford, WA (Appendix A). This report documents the activities carried out as a result of that planning. Campaign IV, the fourth and final step towards the Semi-Integrated Pilot Plant (SIPP) task, conducted by the Savannah River National Laboratory (SRNL) at the Savannah River Site, was to take the several recycle streams produced in Campaign III, the third step of the task, and combine them with other simulated recycle and chosen waste streams. (Campaign III was fed recycles from Campaign II, as Campaign II was fed by Campaign I.) The combined stream was processed in a fashion that mimicked the pretreatment operations of the DOE River Protection Project--Waste Treatment and Immobilization Plant (RPP-WTP) with the exception of the Ion Exchange Process. The SIPP task is considered semi-integrated because it only deals with the pretreatment operations of the RPP-WTP. That is, the pilot plant starts by receiving waste from the tank farm and ends when waste is processed to the point of being sent for vitrification. The resulting pretreated LAW and HLW simulants produced by the SIPP were shipped to VSL (Vitreous State Laboratory) and successfully vitrified in pilot WTP melters. Within the SIPP task these steps are referred to as Campaigns and there were four Campaigns in all. Campaign I, which is completely different than other campaigns, subjected a simulant of Hanford Tank 241-AY-102/C-106 (AY102) waste to cross-flow ultrafiltration only and in that process several important recycle streams were produced as a result of washing the simulant and cleaning the cross-flow filter. These streams were fed to subsequent campaigns and that work was

  7. Final Report: RPP-WTP Semi-Integrated Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    Duignan, M. R.; Adamson, D. J.; Calloway, T. B.; Fowley, M. D.; Qureshi, Z. H.; Steimke, J. L.; Williams, M. R.; Zamecnik, J. R.

    2005-06-01

    In August 2004 the last of the SIPP task testing ended--a task that formally began with the issuance of the RPP-WTP Test Specification in June 2003. The planning for the task was a major effort in itself and culminated with the input of all stakeholders, DOE, Bechtel National, Inc., Washington Group International, in October 2003 at Hanford, WA (Appendix A). This report documents the activities carried out as a result of that planning. Campaign IV, the fourth and final step towards the Semi-Integrated Pilot Plant (SIPP) task, conducted by the Savannah River National Laboratory (SRNL) at the Savannah River Site, was to take the several recycle streams produced in Campaign III, the third step of the task, and combine them with other simulated recycle and chosen waste streams. (Campaign III was fed recycles from Campaign II, as Campaign II was fed by Campaign I.) The combined stream was processed in a fashion that mimicked the pretreatment operations of the DOE River Protection Project--Waste Treatment and Immobilization Plant (RPP-WTP) with the exception of the Ion Exchange Process. The SIPP task is considered semi-integrated because it only deals with the pretreatment operations of the RPP-WTP. That is, the pilot plant starts by receiving waste from the tank farm and ends when waste is processed to the point of being sent for vitrification. The resulting pretreated LAW and HLW simulants produced by the SIPP were shipped to VSL (Vitreous State Laboratory) and successfully vitrified in pilot WTP melters. Within the SIPP task these steps are referred to as Campaigns and there were four Campaigns in all. Campaign I, which is completely different than other campaigns, subjected a simulant of Hanford Tank 241-AY-102/C-106 (AY102) waste to cross-flow ultrafiltration only and in that process several important recycle streams were produced as a result of washing the simulant and cleaning the cross-flow filter. These streams were fed to subsequent campaigns and that work was

  8. Pathogenic amoebae in power-plant cooling lakes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Tyndall, R.L.; Willaert, E.; Stevens, A.R.

    1981-06-01

    Cooling waters and associated algae and sediments from four northern and four southern/western electric power plants were tested for the presence of pathogenic amoebae. Unheated control waters and algae/sediments from four northern and five southern/western sites were also tested. When comparing results from the test versus control sites, a significantly higher proportion (P less than or equal to 0.05) of the samples from the test sites were positive for thermophilic amoeba, thermophilic Naegleria and pathogenic Naegleria. The difference in number of samples positive for thermophilic Naegleria between heated and unheated waters, however, was attributable predominantly to the northern waters and algae/sediments. While two of four northern test sites yielded pathogenic Naegleria, seven of the eight isolates were obtained from one site. Seasonality effects relative to the isolation of the pathogen were also noted at this site. One pathogen was isolated from a southwestern test site. Pathogens were not isolated from any control sites. Some of the pathogenic isolates were analyzed serologically and classified as pathogenic Naegleria fowleri. Salinity, pH, conductivity, and bacteriological profiles did not obviously correlate with the presence or absence of pathogenic Naegleria. While thermal addition was significantly associated with the presence of thermophilic Naegleria (P less than or equal to 0.05), the data implicate other as yet undefined parameters associated with the presence of the pathogenic thermophile. Until further delineation of these parameters is effected, generalizations cannot be made concerning the effect of thermal impact on the growth of pathogenic amoeba in a particular cooling system.

  9. [Protective properties of avermectine complex and plant growth regulators].

    Science.gov (United States)

    Iamborko, N A; Pindrus, A A

    2009-01-01

    Antimutagen properties of avermectine complex of Avercom synthesized by Streptomyces avermitilis UCM Ac-2161, and growth regulators of plants (GRP) of bioagrostim-extra, ivin and emistim-C have been revealed in experiments with test-cultures of Salmonella typhimurium TA 100, TA 98. Avercom and plant growth regulators neutralize by toxication 27-48% and mutagen action of pesticides on soil microbial associations by 19.0-30.0%.

  10. Plant growth regulation of Bt-cotton through Bacillus species.

    Science.gov (United States)

    Pindi, Pavan Kumar; Sultana, Tasleem; Vootla, Praveen Kumar

    2014-06-01

    Deccan plateau in India periodically experiences droughts due to irregular rain fall and the soil in many parts of the region is considered to be poor for farming. Plant growth promoting rhizobacteria are originally defined as root-colonizing bacteria, i.e., Bacillus that cause either plant growth promotion or biological control of plant diseases. The study aims at the isolation of novel Bacillus species and to assess the biotechnological potential of the novel species as a biofertilizer, with respect to their plant growth promoting properties as efficient phosphate-solubilizing bacteria. Seven different strains of Bacillus were isolated from cotton rhizosphere soil near boys' hostel of Palamuru University which belongs to Deccan plateau. Among seven isolated strains, Bacillus strain-7 has shown maximum support for good growth of eight cotton cultivars. This bacterial species is named Bacillus sp. PU-7 based on the phenotypic and phylogenetic analysis. Among eight cotton cultivars, Mahyco has shown high levels of IAA, proteins, chlorophyll, sugars and low level of proline. Efficacy of novel Bacillus sp. PU-7 with Mahyco cultivar has been checked experimentally at field level in four different cotton grown agricultural soils. The strains supported plant growth in almost all the cases, especially in the deep black soil, with a clear evidence of maximum plant growth by increased levels of phytohormone production and biochemical analysis, followed by shallow black soil. Hence, it is inferred that the novel isolate can be used as bioinoculant in the cotton fields.

  11. Effects of different plant growth inhibitors on growth and flowering of narcissus

    Institute of Scientific and Technical Information of China (English)

    Ren Xuqin

    2003-01-01

    This study was conducted to determine effects of four plant growth inhibitors viz. PP333, Het, CCC and B9 with different concentrations on growth and flowering of narcissus. The results indicated that the narcissus treated with certain concentration inhibitors could grow shorter plants with shorter scapes of flower and smaller leaves than the check, and the compact, straight and coordinate plants improve the decorative value obviously.

  12. Plant growth with new fluorescent lamps : II. Growth and reproduction of mature bean plants and dwarf marigold plants.

    Science.gov (United States)

    Thomas, A S; Dunn, S

    1966-06-01

    Bean and marigold plants were grown to maturity under several kinds of fluorescent lamps to evaluate the effects of spectral differences on development and reproduction. Six kinds of lamps were tested including five lamps that were used in closely related experiments on tomato seedling growth (THOMAS and DUNN, 1967). Evaluation was by fresh- and dry-weight yields of immature and mature pods, and of vegetative tops of plants for bean; and by flowering and fresh-and dry-weight yields for marigold.Bean plants grown under two experimental lamps, Com I and IR III produced significantly higher fresh- and dry-weight yields of both mature and total pods than under Warm-white lamps. This effect could be attributed largely to the considerable energy emitted by the experimental lamps in the red and far-red, as compared to a larger emission in the green and blue for the Warm-white lamps. The differences in the yields for immature pods and vegetative portions of the mature tops were not significant.In a comparison of the effects of three experimental lamps with those of three commercial lamps on growth response of bean plants, the yields were in general higher for the experimental lamps, except for immature pods. The yields of vegetative tops were significantly greater for the 78/22 lamp over the yields for all other lamps. The larger proportion of red and far-red light emitted by the experimental lamps is again the probable cause of the higher yields with these lamps.Two sets of experiments on growth and flowering of marigold under various experimental and commercial lamps were largely inconclusive although there was some indication of beneficial effects by the experimental lamps.In general, the results with bean agree with those for tomato (THOMAS and DUNN, 1967), in that best growth was obtained with a lamp high in red light emission, a moderate amount in the far-red, and very little in the blue part of the spectrum.

  13. 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.

  14. Differential effect of metals/metalloids on the growth and element uptake of mesquite plants obtained from plants grown at a copper mine tailing and commercial seeds.

    Science.gov (United States)

    Haque, N; Peralta-Videa, J R; Duarte-Gardea, M; Gardea-Torresdey, J L

    2009-12-01

    The selection of appropriate seeds is essential for the success of phytoremediation/restoration projects. In this research, the growth and elements uptake by the offspring of mesquite plants (Prosopis sp.) grown in a copper mine tailing (site seeds, SS) and plants derived from vendor seeds (VS) was investigated. Plants were grown in a modified Hoagland solution containing a mixture of Cu, Mo, Zn, As(III) and Cr(VI) at 0, 1, 5 and 10 mg L(-1) each. After one week, plants were harvested and the concentration of elements was determined by using ICP-OES. At 1 mg L(-1), plants originated from SS grew faster and longer than control plants (0 mg L(-1)); whereas plants grown from VS had opposite response. At 5 mg L(-1), 50% of the plants grown from VS did not survive, while plants grown from SS had no toxicity effects on growth. Finally, plants grown from VS did not survive at 10 mg L(-1) treatment, whilst 50% of the plants grown from SS survived. The ICP-OES data demonstrated that at 1 mg L(-1) the concentration of all elements in SS plants was significantly higher compared to control plants and VS plants. While at 5 mg L(-1), the shoots of SS plants had significantly more Cu, Mo, As, and Cr. The results suggest that SS could be a better source of plants intended to be used for phytoremediation of soil impacted with Cu, Mo, Zn, As and Cr.

  15. [Controls of the plant endomembrane-secretory pathway]. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-31

    These studies are focused on elucidating the molecular structure of plant cell membranes with special reference to cell surface glycoproteins. The studies reported herein include use of monoclonal antibodies to characterize cell surface epitopes, construction of cDNA libraries of cell surface proteins, isolation of plant cell mutants by flow cytometry, detection of beta-glucouronidase marker enzyme systems in plants, expression go VSVG (the major envelope glycoprotein of Vesicular Stomatis Virus) in plant cells, and control of gene expression of cell membrane glycoproteins.(DT)

  16. The effect of plant growth regulators on height control in potted Arundina graminifolia orchids (Growth regulators in Arundina graminifolia

    Directory of Open Access Journals (Sweden)

    Christina da Silva Wanderley

    2014-08-01

    Full Text Available Orchids have become an important portion of the international floriculture market.  Arundina graminifolia is a terrestrial orchid that produces attractive flowers, and, although the species could be a potential candidate for the floriculture market, its considerable height makes it difficult to transport and commercialize.  A number of plant growth regulators have been utilized to control plant height in ornamentals and other species.  Thus, the aim of this study was to evaluate the efficiency of growth regulators, paclobutrazol and chlormequat chloride on the vegetative development of containerized A. graminifolia orchid aiming at height control.  Paclobutrazol (Cultar was applied at 0, 5, 10, and 20 mg L-1, and CCC (Cycocel was applied at 0, 2000, 4000, and 6000 mg L-1. The plants were assessed monthly for the plant height and number of shoots per container. CCC had no effect on the final height of plants at the concentrations applied. In contrast, paclobutrazol was effective in controlling plant height at a concentration of 5 mg L-1, but higher concentrations (10 and 20 mg L-1 proved to be toxic to the plants, causing death to the new shoots. Paclobutrazol at lower concentrations offers a viable means for height control in A. graminifolia.

  17. 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.

  18. Growth, Nitrogen Uptake and Flow in Maize Plants Affected by Root Growth Restriction

    Institute of Scientific and Technical Information of China (English)

    Liang-zheng Xu; Jun-fang Niu; Chun-jian Li; Fu-suo Zhang

    2009-01-01

    The objective of the present study was to investigate the influence of a reduced maize root-system size on root growth and nitrogen (N) uptake and flow within plants. Restriction of shoot-borne root growth caused a strong decrease in the absorption of root: shoot dry weight ratio and a reduction in shoot growth. On the other hand, compensatory growth and an increased N uptake rate in the remaining roots were observed. Despite the limited long-distance transport pathway in the mesocotyl with restriction of shoot-borne root growth, N cycling within these plants was higher than those in control plants, implying that xylem and phloem flow velocities via the mesocotyl were considerably higher than in plants with an intact root system. The removal of the seminal roots in addition to restricting shoot-borne root development did not affect whole plant growth and N uptake, except for the stronger compensatory growth of the primary roots. Our results suggest that an adequate N supply to maize plant is maintained by compensatory growth of the remaining roots, increased N uptake rate and flow velocities within the xylem and phloem via the mesocotyl, and reduction in the shoot growth rate.

  19. Materials and methods to increase plant growth and yield

    Energy Technology Data Exchange (ETDEWEB)

    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.

  20. Plant growth control by light spectrum

    NARCIS (Netherlands)

    Ieperen, van W.

    2016-01-01

    Plants are sessile organisms that have to cope with their environment as it is exposed to them in nature. To do so, they developed systems to sense environmental signals and to integrate these with endogenous developmental programs. As a result, they are well equipped to survive and flourish in

  1. Plant growth control by light spectrum

    NARCIS (Netherlands)

    Ieperen, van W.

    2016-01-01

    Plants are sessile organisms that have to cope with their environment as it is exposed to them in nature. To do so, they developed systems to sense environmental signals and to integrate these with endogenous developmental programs. As a result, they are well equipped to survive and flourish in v

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

    Directory of Open Access Journals (Sweden)

    Adam Barrada

    2015-08-01

    Full Text Available 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.

  3. 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

  4. 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

    2015-08-19

    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.

  5. Water use, productivity and interactions among desert plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Ehleringer, J.R.

    1992-11-17

    Productivity, stability, and competitive interactions among ecosystem components within aridlands are key processes related directly to water in deserts. This project assumes that integrated aspects of plant metabolism provide insight into the structure and function of plant communities and ecosystems. While it is difficult to extrapolate from instantaneous physiological observations to higher scales, such as whole plant performance or to the interactions between plants as components of ecosystems, several key aspects of plant metabolism are scalable. Analyses of stable isotopic composition in plant tissues at natural abundance levels provide a useful tool that can provide insight into the consequences of physiological processes over temporal and spatial scales. Some plant processes continuously fractionate among light and heavy stable isotopic forms of an element; over time this results in integrated measures of plant metabolism. For example, carbon isotope fractionation during photosynthesis results in leaf carbon isotopic composition that is a measure of the set-point for photosynthetic metabolism and of water-use efficiency. Thus it provides information on the temporal scaling of a key physiological process.

  6. Final Report: 17th international Symposium on Plant Lipids

    Energy Technology Data Exchange (ETDEWEB)

    Christoph Benning

    2007-03-07

    This meeting covered several emerging areas in the plant lipid field such as the biosynthesis of cuticle components, interorganelle lipid trafficking, the regulation of lipid homeostasis, and the utilization of algal models. Stimulating new insights were provided not only based on research reports based on plant models, but also due to several excellent talks by experts from the yeast field.

  7. Fresh perspectives on the roles of arbuscular mycorrhizal fungi in plant nutrition and growth.

    Science.gov (United States)

    Smith, Sally E; Smith, F Andrew

    2012-01-01

    Recent research on arbuscular mycorrhizas has demonstrated that AM fungi play a significant role in plant phosphorus (P) uptake, regardless of whether the plant responds positively to colonization in terms of growth or P content. Here we focus particularly on implications of this finding for consideration of the balance between organic carbon (C) use by the fungi and P delivery (i.e. the C-P trade between the symbionts). Positive growth responses to arbuscular mycorrhizal (AM) colonization are attributed frequently to increased P uptake via the fungus, which results in relief of P deficiency and increased growth. Zero AM responses, compared with non-mycorrhizal (NM) plants, have conventionally been attributed to failure of the fungi to deliver P to the plants. Negative responses, combined with excessive C use, have been attributed to this failure. The fungi were viewed as parasites. Demonstration that the AM pathway of P uptake operates in such plants indicates that direct P uptake by the roots is reduced and that the fungi are not parasites but mutualists because they deliver P as well as using C. We suggest that poor plant growth is the result of P deficiency because AM fungi lower the amount of P taken up directly by roots but the AM uptake of P does compensate for the reduction. The implications of interplay between direct root uptake and AM fungal uptake of P also include increased tolerance of AM plants to toxins such as arsenate and increased success when competing with NM plants. Finally we discuss the new information on C-P trade in the context of control of the symbiosis by the fungus or the plant, including new information (from NM plants) on sugar transport and on the role of sucrose in the signaling network involved in responses of plants to P deprivation.

  8. 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

  9. 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

  10. Plant Growth Promotion Induced by Phosphate Solubilizing Endophytic Pseudomonas Isolates

    Directory of Open Access Journals (Sweden)

    Nicholas eOtieno

    2015-07-01

    Full Text Available The use of plant growth promoting bacterial inoculants as live microbial biofertilisers provides a promising alternative to chemical fertilisers and pesticides. Inorganic phosphate solubilisation is one of the major mechanisms of plant growth promotion by plant associated bacteria. This involves bacteria releasing organic acids into the soil which solubilise the phosphate complexes converting them into ortho-phosphate which is available for plant up-take and utilisation. The study presented here describes the ability of endophytic bacterial isolates to produce gluconic acid, solubilise insoluble phosphate and stimulate the growth of Pea plants (Pisum sativum. This study also describes the genetic systems within three of these endophyte isolates thought to be responsible for their effective phosphate solubilising abilities. The results showed that many of the endophytic isolates produced gluconic acid (14-169 mM and have moderate to high phosphate solubilisation capacities (~ 400-1300 mg L-1. When inoculated to Pea plants grown in sand/soil under soluble phosphate limiting conditions, the endophyte isolates that produced medium to high levels of gluconic acid also displayed enhanced plant growth promotion effects.

  11. 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.

  12. 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.

  13. Dynamical Riemannian Geometry and Plant Growth

    CERN Document Server

    Pulwicki, Julia

    2010-01-01

    A new model for biological growth is introduced that couples the geometry of an organism (or part of the organism) to the flow and deposition of material. The model has three dynamical variables (a) a Riemann metric tensor for the geometry, (b) a transport velocity of the material and (c) a material density. While the model was developed primarily to determine the effects of geometry (i.e. curvature and scale changes) in two-dimensional systems such as leaves and petals, it can be applied to any dimension. Results for one dimensional systems are presented and compared to measurements of growth made on blades of grass and corn roots. It is found that the model is able to reproduce many features associated with botanical growth.

  14. 77 FR 27210 - Publication of the Final National Wetland Plant List

    Science.gov (United States)

    2012-05-09

    ... Conservation Service (NRCS), is announcing the availability of the final 2012 National Wetland Plant List (NWPL... wetland determinations under the Clean Water Act and the Wetland Conservation Provisions of the Food... Department of the Army, Corps of Engineers Publication of the Final National Wetland Plant List AGENCY:...

  15. IMPROVING TACONITE PROCESSING PLANT EFFICIENCY BY COMPUTER SIMULATION, Final Report

    Energy Technology Data Exchange (ETDEWEB)

    William M. Bond; Salih Ersayin

    2007-03-30

    This project involved industrial scale testing of a mineral processing simulator to improve the efficiency of a taconite processing plant, namely the Minorca mine. The Concentrator Modeling Center at the Coleraine Minerals Research Laboratory, University of Minnesota Duluth, enhanced the capabilities of available software, Usim Pac, by developing mathematical models needed for accurate simulation of taconite plants. This project provided funding for this technology to prove itself in the industrial environment. As the first step, data representing existing plant conditions were collected by sampling and sample analysis. Data were then balanced and provided a basis for assessing the efficiency of individual devices and the plant, and also for performing simulations aimed at improving plant efficiency. Performance evaluation served as a guide in developing alternative process strategies for more efficient production. A large number of computer simulations were then performed to quantify the benefits and effects of implementing these alternative schemes. Modification of makeup ball size was selected as the most feasible option for the target performance improvement. This was combined with replacement of existing hydrocyclones with more efficient ones. After plant implementation of these modifications, plant sampling surveys were carried out to validate findings of the simulation-based study. Plant data showed very good agreement with the simulated data, confirming results of simulation. After the implementation of modifications in the plant, several upstream bottlenecks became visible. Despite these bottlenecks limiting full capacity, concentrator energy improvement of 7% was obtained. Further improvements in energy efficiency are expected in the near future. The success of this project demonstrated the feasibility of a simulation-based approach. Currently, the Center provides simulation-based service to all the iron ore mining companies operating in northern

  16. Isolation of phytohormones producing plant growth promoting ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-11-02

    Nov 2, 2009 ... soil of Pakistan and their growth promoting effects have been documented on rice ... tion of total salt and salt ions: Cl-, Mg, Na, K and HCO3. - in .... IAA was eluted at 280 nm wavelength while GA3, t-zr and ABA were eluted at ...

  17. Preconstruction of the Honey Lake Hybrid Power Plant: Final report

    Energy Technology Data Exchange (ETDEWEB)

    1988-04-30

    The work undertaken under this Contract is the prosecution of the preconstruction activities, including preliminary engineering design, well field development, completion of environmental review and prosecution of permits, and the economic and financial analysis of the facility. The proposed power plant is located in northeastern California in Lassen County, approximately 25 miles east of the town of Susanville. The power plant will use a combination of wood residue and geothermal fluids for power generation. The plant, when fully constructed, will generate a combined net output of approximately 33 megawatts which will be sold to Pacific Gas and Electric Company (PGandE) under existing long-term power sales contracts. Transfer of electricity to the PGandE grid will require construction of a 22-mile transmission line from the power plant to Susanville. 11 refs., 12 figs., 4 tabs.

  18. Hybrid Cooling for Geothermal Power Plants: Final ARRA Project Report

    Energy Technology Data Exchange (ETDEWEB)

    Bharathan, D.

    2013-06-01

    Many binary-cycle geothermal plants use air as the heat rejection medium. Usually this is accomplished by using an air-cooled condenser (ACC) system to condense the vapor of the working fluid in the cycle. Many air-cooled plants suffer a loss of production capacity of up to 50% during times of high ambient temperatures. Use of limited amounts of water to supplement the performance of ACCs is investigated. Deluge cooling is found to be one of the least-cost options. Limiting the use of water in such an application to less than one thousand operating hours per year can boost plant output during critical high-demand periods while minimizing water use in binary-cycle geothermal power plants.

  19. How do plants enlarge? A balancing act; Final report

    Energy Technology Data Exchange (ETDEWEB)

    Boyer, J.S.

    1996-12-31

    Cells of plants are surrounded by strong walls that prevent rupture from internal pressures that can be two or three times that of an automobile tire. In this way, the walls protect the cytoplasm. However, at the same time, the cells can enlarge as they grow. How this balancing act works and how it enlarges the plant were the subject of a recent conference at the University of Delaware in Lewes. The aim was to identify areas for future research that could explain the enlargement of whole plants. There is a large practical need to predict and modify plant enlargement but the additional processes that overlie the molecular ones need to be integrated with the molecular information before a picture will emerge. How best to accomplish this involved input from cross-disciplinary areas in biomechanics, physics and engineering as well as molecular biology, biochemistry and ultrastructure.

  20. 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.

  1. Alleviation of Salt Stress in Pepper (Capsicum annum L.) Plants by Plant Growth-Promoting Rhizobacteria.

    Science.gov (United States)

    Hahm, Mi-Seon; Son, Jin-Soo; Hwang, Ye-Ji; Kwon, Duk-Ki; Ghim, Sa-Youl

    2017-08-08

    In the present study, we demonstrate that the growth of salt-stressed pepper plants is improved by inoculation with plant growth-promoting rhizobacteria (PGPR). Three PGPR strains (Microbacterium oleivorans KNUC7074, Brevibacterium iodinum KNUC7183, and Rhizobium massiliae KNUC7586) were isolated from the rhizosphere of pepper plants growing in saline soil, and pepper plants inoculated with these PGPR strains exhibited significantly greater plant height, fresh weight, dry weight, and total chlorophyll content than non-inoculated plants. In addition, salt-stressed pepper plants that were inoculated with B. iodinum KNUC7183 and R. massiliae KNUC7586 possessed significantly different total soluble sugar and proline contents from non-inoculated controls, and the activity of several antioxidant enzymes (ascorbate peroxidase, guaiacol peroxidase, and catalase) was also elevated in PGPR-treated plants under salt stress. Overall, these results suggest that the inoculation of pepper plants with M. oleivorans KNUC7074, B. iodinum KNUC7183, and R. massiliae KNUC7586 can alleviate the harmful effects of salt stress on plant growth.

  2. Effects of plant growth regulators on survival and recovery growth following cryopreservation.

    Science.gov (United States)

    Turner, S R; Touchell, D H; Senaratna, T; Bunn, E; Tan, B; Dixon, K W

    2001-01-01

    Studies on the effects of plant growth regulators (PGRs) on survival, recovery and post-recovery growth of shoot apices following cryopreservation are limited. In this study, the effects of plant growth regulators in both the culture phase and the recovery phase of cryostorage were examined for the rare plant species, Anigozanthos viridis ssp terraspectans Hopper. Survival of shoot apices was not correlated to cytokinin or auxin treatments administered in culture media prior to cryostorage. In recovery media, the plant growth regulators, kinetin, zeatin (cytokinins), IAA, (auxin) and GA3 were examined for their effect following cryopreservation. It was found that the application of a combination of cytokinin and 0.5 microM GA3 from day zero was the most appropriate for obtaining vigorously growing plantlets following LN immersion. This combination proved to be more effective than basal medium, zeatin or kinetin treatments.

  3. Growth Characteristics of Rhizophagus clarus Strains and Their Effects on the Growth of Host Plants.

    Science.gov (United States)

    Lee, Eun-Hwa; Eom, Ahn-Heum

    2015-12-01

    Arbuscular mycorrhizal fungi (AMF) are ubiquitous in the rhizosphere and form symbiotic relationships with most terrestrial plant roots. In this study, four strains of Rhizophagus clarus were cultured and variations in their growth characteristics owing to functional diversity and resultant effects on host plant were investigated. Growth characteristics of the studied R. clarus strains varied significantly, suggesting that AMF retain high genetic variability at the intraspecies level despite asexual lineage. Furthermore, host plant growth response to the R. clarus strains showed that genetic variability in AMF could cause significant differences in the growth of the host plant, which prefers particular genetic types of fungal strains. These results suggest that the intraspecific genetic diversity of AMF could be result of similar selective pressure and may be expressed at a functional level.

  4. 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.

  5. Effect of planting density on plant growth and camptothecin content of Camptotheca acuminata seedlings

    Institute of Scientific and Technical Information of China (English)

    WEIHuan-yong; WANGYang; WANGZhen-yue; YANXiu-feng

    2005-01-01

    C. acuminata seedlings cultivated in greenhouse were transplanted into the fields with 5 designed planting densities (11, 16, 25,44 and 100 plants·m-2) in May of 2004 and were harvested in the middle of September of 2004. The seedling growth indexes including plant height and crown width, biomass allocation, camptothecin (CPT) content and CPT yield of different organs (young leaf, old leaf, stem,and root) were studied. For the 5 selected planting densities, the plant biomass, height, crown width, and total leaf area of C. acuminata seedlings all showed highest values at the planting density of 25 plants ·m-2. CPT content in young leaves was higher than that in other organs of seedlings and presented an obvious change with the variation of planting densities and with the highest value at density of 100plants·m-2, while for other organs no significant variation in CPT content was found with change of planting density. The accumulation of CPT was enhanced significantly at the planting density of 25 plants·m-2. It is concluded that for the purpose to get raw materials with more CPT from C. acuminata, the optimal planting density of C. acuminata seedlings should be designed as 25 plants·m-2.

  6. Gravity sensing, a largely misunderstood trigger of plant orientated growth.

    Science.gov (United States)

    Lopez, David; Tocquard, Kévin; Venisse, Jean-Stéphane; Legué, Valerie; Roeckel-Drevet, Patricia

    2014-01-01

    Gravity is a crucial environmental factor regulating plant growth and development. Plants have the ability to sense a change in the direction of gravity, which leads to the re-orientation of their growth direction, so-called gravitropism. In general, plant stems grow upward (negative gravitropism), whereas roots grow downward (positive gravitropism). Models describing the gravitropic response following the tilting of plants are presented and highlight that gravitropic curvature involves both gravisensing and mechanosensing, thus allowing to revisit experimental data. We also discuss the challenge to set up experimental designs for discriminating between gravisensing and mechanosensing. We then present the cellular events and the molecular actors known to be specifically involved in gravity sensing.

  7. Gravity sensing, a largely misunderstood trigger of plant orientated growth

    Directory of Open Access Journals (Sweden)

    David eLopez

    2014-11-01

    Full Text Available Gravity is a crucial environmental factor regulating plant growth and development. Plants have the ability to sense a change in the direction of gravity, which leads to the re-orientation of their growth direction, so-called gravitropism. In general, plant stems grow upward (negative gravitropism, whereas roots grow downward (positive gravitropism. Models describing the gravitropic response following the tilting of plants are presented and highlight that gravitropic curvature involves both gravisensing and mechanosensing, thus allowing to revisit experimental data. We also discuss the challenge to set up experimental designs for discriminating between gravisensing and mechanosensing. We then present the cellular events and the molecular actors known to be specifically involved in gravity sensing.

  8. Light-regulated plant growth and development.

    Science.gov (United States)

    Kami, Chitose; Lorrain, Séverine; Hornitschek, Patricia; Fankhauser, Christian

    2010-01-01

    Plants are sessile and photo-autotrophic; their entire life cycle is thus strongly influenced by the ever-changing light environment. In order to sense and respond to those fluctuating conditions higher plants possess several families of photoreceptors that can monitor light from UV-B to the near infrared (far-red). The molecular nature of UV-B sensors remains unknown, red (R) and far-red (FR) light is sensed by the phytochromes (phyA-phyE in Arabidopsis) while three classes of UV-A/blue photoreceptors have been identified: cryptochromes, phototropins, and members of the Zeitlupe family (cry1, cry2, phot1, phot2, ZTL, FKF1, and LKP2 in Arabidopsis). Functional specialization within photoreceptor families gave rise to members optimized for a wide range of light intensities. Genetic and photobiological studies performed in Arabidopsis have shown that these light sensors mediate numerous adaptive responses (e.g., phototropism and shade avoidance) and developmental transitions (e.g., germination and flowering). Some physiological responses are specifically triggered by a single photoreceptor but in many cases multiple light sensors ensure a coordinated response. Recent studies also provide examples of crosstalk between the responses of Arabidopsis to different external factors, in particular among light, temperature, and pathogens. Although the different photoreceptors are unrelated in structure, in many cases they trigger similar signaling mechanisms including light-regulated protein-protein interactions or light-regulated stability of several transcription factors. The breath and complexity of this topic forced us to concentrate on specific aspects of photomorphogenesis and we point the readers to recent reviews for some aspects of light-mediated signaling (e.g., transition to flowering).

  9. 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...

  10. Influence of plant growth on degradation of linear alkylbenzene sulfonate in sludge-amended soil.

    Science.gov (United States)

    Mortensen, G K; Egsgaard, H; Ambus, P; Jensen, E S; Grøn, C

    2001-01-01

    Widespread application of sewage sludge to agricultural soils in Denmark has led to concern about the possible accumulation and effects of linear alkylbenzene sulfonate (LAS) in the soil ecosystem. Therefore, we have studied the uptake and degradation of LAS in greenhouse pot experiments. Sewage sludge was incorporated into a sandy soil to give a range from very low to very high applications (0.4 to 90 Mg dry wt. ha(-1)). In addition, LAS was added as water solutions. The soil was transferred to pots and sown with barley (Hordeum vulgare L. cv. Apex), rape (Brassica napus L. cv. Hyola 401), or carrot (Daucus carota L.). Also, plant-free controls were established. For all additions there was no plant uptake above the detection limit at 0.5 mg LAS kg(-1) d.w, but plant growth stimulated the degradation. With a growth period of 30 d, LAS concentrations in soil from pots with rape had dropped from 27 to 1.4 mg kg(-1) dry wt., but in plant-free pots the concentration decreased only to 2.4 mg kg(-1) dry wt. When LAS was added as a spike, the final concentration in soil from planted pots was 0.7 mg kg(-1) dry wt., but in pots without plants the final concentration was much higher (2.5 mg kg(-1) dry wt.). During degradation, the relative fraction of homologues C10, C11, and C12 decreased, while C13 increased.

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

    OpenAIRE

    Farzad Aslani; Samira Bagheri; Nurhidayatullaili Muhd Julkapli; Abdul Shukor Juraimi; Farahnaz Sadat Golestan Hashemi; Ali Baghdadi

    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 ra...

  12. Portsmouth Gaseous Diffusion Plant expansion: final environmental statement. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    1977-09-01

    Volume 1 is comprised of chapters on: background and description; environmental impacts of add-on gaseous diffusion plant; unavoidable adverse environmental effects; alternatives; relationship between short-term uses and long-term productivity; relationship of program to land-use plans, policies, and controls; irreversible and irretrievable commitments of resources; cost-benefit analysis; and response to comment letters. (LK)

  13. Delays in nuclear power plant construction. Volume II. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Mason, G.E.; Larew, R.E.; Borcherding, J.D.; Okes, S.R. Jr.; Rad, P.F.

    1977-12-14

    The report identifies barriers to shortening nuclear power plant construction schedules and recommends research efforts which should minimize or eliminate the identified barriers. The identified barriers include (1) Design and Construction Interfacing Problems; (2) Problems Relating to the Selection and Use of Permanent Materials and Construction Methods; (3) Construction Coordination and Communication Problems; and (4) Problems Associated with Manpower Availability and Productivity.

  14. The Mars Plant Growth Experiment and Implications for Planetary Protection

    Science.gov (United States)

    Smith, Heather

    Plants are the ultimate and necessary solution for O2 production at a human base on Mars. Currently it is unknown if seeds can germinate on the Martian surface. The Mars Plant growth experiment (MPX) is a proposal for the first step in the development of a plant- based O2 production system by demonstrating plant germination and growth on the Martian surface. There is currently no planetary protection policy in place that covers plants on the Martian surface. We describe a planetary protection plan in compliance with NASA and COSPAR policy for a closed plant growth chamber on a Mars rover. We divide the plant growth chamber into two categories for planetary protection, the Outside: the outside of the chamber exposed to the Martian environment, and the Inside: the inside of the chamber which is sealed off from Mars atmosphere and contains the plant seeds and ancillary components for seed growth. We will treat outside surfaces of the chamber as other outside surfaces on the rover, wiped with a mixture of isopropyl alcohol and water as per Category IVb planetary protection requirements. All internal components of the MPX except the seeds and camera (including the water system, the plant growth stage and interior surface walls) will be sterilized by autoclave and subjected to sterilizing dry heat at a temperature of 125°C at an absolute humidity corresponding to a relative humidity of less than 25 percent referenced to the standard conditions of 0°C and 760 torr pressure. The seeds and internal compartments of the MPX in contact with the growth media will be assembled and tested to be free of viable microbes. MPX, once assembled, cannot survive Dry Heat Microbial Reduction. The camera with the radiation and CO2 sensors will be sealed in their own container and vented through HEPA filters. The seeds will be vernalized (microbe free) as per current Space Station methods described by Paul et al. 2001. Documentation of the lack of viable microbes on representative seeds

  15. 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.

  16. Designing Extraterrestrial Plant Growth Habitats with Low Pressure Atmospheres

    Science.gov (United States)

    Corey, Kenneth A.

    2002-01-01

    In-situ resource utilization, provision of human life support requirements by bioregenerative methods, and engineering constraints for construction and deployment of plant growth structures on the surface of Mars all suggest the need for plant growth studies at hypobaric pressures. Past work demonstrated that plants will likely tolerate and grow at pressures at or below 10 kPa. Based upon this premise, concepts are developed for the design of reduced pressure atmospheres in lightweight, inflatable structures for plant growth systems on Mars with the goals of maximizing design simplicity and the use of local resources. A modular pod design is proposed as it could be integrated with large-scale production systems. Atmospheric modification of pod clusters would be based upon a pulse and scrub system using mass flow methods for atmospheric transport. A specific modification and control scenario is developed for a lettuce pod to illustrate the dynamics of carbon dioxide and oxygen exchange within a pod. Considerations of minimal atmospheric crop requirements will aid in the development of engineering designs and strategies for extraterrestrial plant growth structures that employ rarefied atmospheres.

  17. Use of Hydrogen Peroxide to Disinfect Hydroponic Plant Growth Systems

    Science.gov (United States)

    Barta, Daniel J.; Henderson, Keith

    2000-01-01

    Hydrogen peroxide was studied as an alternative to conventional bleach and rinsing methods to disinfect hydroponic plant growth systems. A concentration of 0.5% hydrogen peroxide was found to be effective. Residual hydrogen peroxide can be removed from the system by repeated rinsing or by flowing the solution through a platinum on aluminum catalyst. Microbial populations were reduced to near zero immediately after treatment but returned to pre-disinfection levels 2 days after treatment. Treating nutrient solution with hydrogen peroxide and planting directly into trays being watered with the nutrient solution without replenishment, was found to be detrimental to lettuce germination and growth.

  18. Evaluating and optimizing horticultural regimes in space plant growth facilities

    Science.gov (United States)

    Berkovich, Y. A.; Chetirkin, P. V.; Wheeler, R. M.; Sager, J. C.

    2004-01-01

    In designing innovative space plant growth facilities (SPGF) for long duration space flight, various limitations must be addressed including onboard resources: volume, energy consumption, heat transfer and crew labor expenditure. The required accuracy in evaluating onboard resources by using the equivalent mass methodology and applying it to the design of such facilities is not precise. This is due to the uncertainty of the structure and not completely understanding the properties of all associated hardware, including the technology in these systems. We present a simple criteria of optimization for horticultural regimes in SPGF: Qmax = max [ M · (EBI) 2/( V · E · T) ], where M is the crop harvest in terms of total dry biomass in the plant growth system; EBI is the edible biomass index (harvest index), V is volume occupied by the crop; E is the crop light energy supply during growth; T is the crop growth duration. The criterion reflects directly on the consumption of onboard resources for crop production.

  19. Microbial phytases in phosphorus acquisition and plant growth promotion.

    Science.gov (United States)

    Singh, Bijender; Satyanarayana, T

    2011-04-01

    Phosphorus (P) is one of the major constituents in energy metabolism and biosynthesis of nucleic acids and cell membranes with an important role in regulation of a number of enzymes. Soil phosphorous is an important macronutrient for plant growth. Phosphorus deficiency in soil is a major problem for agricultural production. Total soil P occurs in either organic or in organic form. Phytic acid as phytate (salts of phytic acid) is the major form of organic phosphorus in soil and it is not readily available to plants as a source of phosphorus because it either forms a complex with cations or adsorbs to various soil components. Phosphate solubilizing microorganisms are ubiquitous in soils and could play an important role in supplying P to plants. Microorganisms utilizing phytate are found in cultivated soils as well as in wetland, grassland and forest soils. Various fungi and bacteria (including plant growth promoting rhizobacteria) hydrolyze this organic form of phosphorus secreting phosphatases such as phytases and acidic/alkaline phosphatases. A large number of transgenic plants have been developed which were able to utilize sodium phytate as sole source of phosphorus. However, the recombinant phytases were similar to their wild type counterparts in terms of their properties. Increased phytase/phosphatase activity in transgenic plants may be an effective approach to promote their phytate-phosphorus utilization. The extracellular phytase activity of transgenic plant roots is a significant factor in the utilization of phosphorus from phytate. Furthermore, this indicated that an opportunity exists for using gene technology to improve the ability of plants to utilize accumulated forms of soil organic phosphorus. This review is focused on the role of phytases and phytase producing microbes in promoting the growth of different plants.

  20. 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.

  1. Target of rapamycin signaling orchestrates growth-defense trade-offs in plants.

    Science.gov (United States)

    De Vleesschauwer, David; Filipe, Osvaldo; Hoffman, Gena; Seifi, Hamed Soren; Haeck, Ashley; Canlas, Patrick; Van Bockhaven, Jonas; De Waele, Evelien; Demeestere, Kristof; Ronald, Pamela; Hofte, Monica

    2017-09-14

    Plant defense to microbial pathogens is often accompanied by significant growth inhibition. How plants merge immune system function with normal growth and development is still poorly understood. Here, we investigated the role of target of rapamycin (TOR), an evolutionary conserved serine/threonine kinase, in the plant defense response. We used rice as a model system and applied a combination of chemical, genetic, genomic and cell-based analyses. We demonstrate that ectopic expression of TOR and Raptor (regulatory-associated protein of mTOR), a protein previously demonstrated to interact with TOR in Arabidopsis, positively regulates growth and development in rice. Transcriptome analysis of rice cells treated with the TOR-specific inhibitor rapamycin revealed that TOR not only dictates transcriptional reprogramming of extensive gene sets involved in central and secondary metabolism, cell cycle and transcription, but also suppresses many defense-related genes. TOR overexpression lines displayed increased susceptibility to both bacterial and fungal pathogens, whereas plants with reduced TOR signaling displayed enhanced resistance. Finally, we found that TOR antagonizes the action of the classic defense hormones salicylic acid and jasmonic acid. Together, these results indicate that TOR acts as a molecular switch for the activation of cell proliferation and plant growth at the expense of cellular immunity. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  2. Dynamics of Plant Growth; A Theory Based on Riemannian Geometry

    CERN Document Server

    Pulwicki, Julia

    2016-01-01

    In this work, a new model for macroscopic plant tissue growth based on dynamical Riemannian geometry is presented. We treat 1D and 2D tissues as continuous, deformable, growing geometries for sizes larger than 1mm. The dynamics of the growing tissue are described by a set of coupled tensor equations in non-Euclidean (curved) space. These coupled equations represent a novel feedback mechanism between growth and curvature dynamics. For 1D growth, numerical simulations are compared to two measures of root growth. First, modular growth along the simulated root shows an elongation zone common to many species of plant roots. Second, the relative elemental growth rate (REGR) calculated in silico exhibits temporal dynamics recently characterized in high-resolution root growth studies but which thus far lack a biological hypothesis to explain them. Namely, the REGR can evolve from a single peak localized near the root tip to a double-peak structure. In our model, this is a direct consequence of considering growth as b...

  3. SPATULA links daytime temperature and plant growth rate.

    Science.gov (United States)

    Sidaway-Lee, Kate; Josse, Eve-Marie; Brown, Alanna; Gan, Yinbo; Halliday, Karen J; Graham, Ian A; Penfield, Steven

    2010-08-24

    Plants exhibit a wide variety of growth rates that are known to be determined by genetic and environmental factors, and different plants grow optimally at different temperatures, indicating that this is a genetically determined character. Moderate decreases in ambient temperature inhibit vegetative growth, but the mechanism is poorly understood, although a decrease in gibberellin (GA) levels is known to be required. Here we demonstrate that the basic helix-loop-helix transcription factor SPATULA (SPT), previously known to be a regulator of low temperature-responsive germination, mediates the repression of growth by cool daytime temperatures but has little or no growth-regulating role under warmer conditions. We show that only daytime temperatures affect vegetative growth and that SPT couples morning temperature to growth rate. In seedlings, warm temperatures inhibit the accumulation of the SPT protein, and SPT autoregulates its own transcript abundance in conjunction with diurnal effects. Genetic data show that repression of growth by SPT is independent of GA signaling and phytochrome B, as previously shown for PIF4. Our data suggest that SPT integrates time of day and temperature signaling to control vegetative growth rate.

  4. Guidelines for implementing the plant monitoring workstation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Duge, W.R.; DeCoster, M.A.

    1996-05-01

    The Plant Monitoring Workstation (PMW) is an integrated set of computer programs that calculate performance of a fossil power plant. PMW is typically configured to calculate heat rate and other performance parameters from on-line instrumentation and off-line test results. PMW was developed by EPRI and currently is available for DEC VAX computers and IBM compatible computers with OS/2. A version that supports Windows is also under development. PMW is one of many computer programs available in the marketplace. An important differentiating feature of PMW is its flexibility to be tailored to individual situations and used interactively. As a result of this flexibility, several setup and configuration decisions have to be made. This Guideline document is meant to help first time users through those setup and configuration decisions.

  5. Effect of drought and heat stresses on plant growth and yield: a review

    Science.gov (United States)

    Lipiec, J.; Doussan, C.; Nosalewicz, A.; Kondracka, K.

    2013-12-01

    Drought and heat stresses are important threat limitations to plant growth and sustainable agriculture worldwide. Our objective is to provide a review of plant responses and adaptations to drought and elevated temperature including roots, shoots, and final yield and management approaches for alleviating adverse effects of the stresses based mostly on recent literature. The sections of the paper deal with plant responses including root growth, transpiration, photosynthesis, water use efficiency, phenotypic flexibility, accumulation of compounds of low molecular mass (eg proline and gibberellins), and expression of some genes and proteins for increasing the tolerance to the abiotic stresses. Soil and crop management practices to alleviate negative effects of drought and heat stresses are also discussed. Investigations involving determination of plant assimilate partitioning, phenotypic plasticity, and identification of most stress-tolerant plant genotypes are essential for understanding the complexity of the responses and for future plant breeding. The adverse effects of drought and heat stress can be mitigated by soil management practices, crop establishment, and foliar application of growth regulators by maintaining an appropriate level of water in the leaves due to osmotic adjustment and stomatal performance.

  6. 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.

  7. Effects of engineered nanomaterials on plants growth: an overview.

    Science.gov (United States)

    Aslani, Farzad; Bagheri, Samira; Muhd Julkapli, Nurhidayatullaili; Juraimi, Abdul Shukor; Hashemi, Farahnaz Sadat Golestan; Baghdadi, Ali

    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.

  8. Plant Growth Biostimulants, Dietary Feed Supplements and Cosmetics Formulated with Supercritical CO2 Algal Extracts

    OpenAIRE

    Izabela Michalak; Katarzyna Chojnacka; Agnieszka Saeid

    2017-01-01

    The review paper presents the use of algal extracts as safe and solvent-free components of plant growth biostimulants, dietary feed additives and cosmetics. Innovative technology that uses extracts obtained by supercritical CO2 extraction, as a method of isolation of biologically active compounds from algal biomass, is presented. An important part of the complete technology is the final formulation of the product. This enabled realization of the further step which was assessment of the utilit...

  9. Regulation of cell division in higher plants. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, Thomas W.

    2000-02-29

    Research in the latter part of the grant period was divided into two parts: (1) expansion of the macromolecular tool kit for studying plant cell division; (2) experiments in which the roles played by plant cell cycle regulators were to be cast in the light of the emerging yeast and animal cell paradigm for molecular control of the mitotic cycle. The first objectives were accomplished to a very satisfactory degree. With regard to the second part of the project, we were driven to change our objectives for two reasons. First, the families of cell cycle control genes that we cloned encoded such closely related members that the prospects for success at raising distinguishing antisera against each were sufficiently dubious as to be impractical. Epitope tagging is not feasible in Pisum sativum, our experimental system, as this species is not realistically transformable. Therefore, differentiating the roles of diverse cyclins and cyclin-dependent kinases was problematic. Secondly, our procedure for generating mitotically synchronized pea root meristems for biochemical studies was far too labor intensive for the proposed experiments. We therefore shifted our objectives to identifying connections between the conserved proteins of the cell cycle engine and factors that interface it with plant physiology and development. In this, we have obtained some very exciting results.

  10. Multiple effects of Bacillus amyloliquefaciens volatile compounds: plant growth promotion and growth inhibition of phytopathogens.

    Science.gov (United States)

    Asari, Shashidar; Matzén, Staffan; Petersen, Mikael Agerlin; Bejai, Sarosh; Meijer, Johan

    2016-06-01

    Biotic interactions through volatile organic compounds (VOC) are frequent in nature. This investigation aimed to study the role of ITALIC! BacillusVOC for the beneficial effects on plants observed as improved growth and pathogen control. Four ITALIC! Bacillus amyloliquefacienssubsp. ITALIC! plantarumstrains were screened for VOC effects on ITALIC! Arabidopsis thalianaCol-0 seedlings and ITALIC! Brassicafungal phytopathogens. VOC from all four ITALIC! Bacillusstrains could promote growth of ITALIC! Arabidopsisplants resulting in increased shoot biomass but the effects were dependent on the growth medium. Dose response studies with UCMB5113 on MS agar with or without root exudates showed significant plant growth promotion even at low levels of bacteria. ITALIC! BacillusVOC antagonized growth of several fungal pathogens ITALIC! in vitro However, the plant growth promotion efficacy and fungal inhibition potency varied among the ITALIC! Bacillusstrains. VOC inhibition of several phytopathogens indicated efficient microbial antagonism supporting high rhizosphere competence of the ITALIC! Bacillusstrains. GC-MS analysis identified several VOC structures where the profiles differed depending on the growth medium. The ability of ITALIC! Bacillusstrains to produce both volatile and soluble compounds for plant growth promotion and disease biocontrol provides examples of rhizosphere microbes as an important ecosystem service with high potential to support sustainable crop production.

  11. Root and bacterial secretions regulate the interaction between plants and PGPR leading to distinct plant growth promotion effects

    Science.gov (United States)

    Plant growth-promoting rhizobacteria (PGPR) have garnered interest in agriculture due to their ability to influence the growth and production of host plants. ATP-binding cassette (ABC) transporters play important roles in plant-microbe interactions by modulating plant root exudation. The present stu...

  12. 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.

  13. Effects of the plant growth regulator, chlormequat, on mammalian fertility.

    Science.gov (United States)

    Sørensen, Martin T; Danielsen, Viggo

    2006-02-01

    This paper summarizes the consequences of exposure to chlormequat, a plant growth regulator, on reproduction in mammals. Plant growth regulators are chemicals used to manipulate plant growth, flowering and fruit yield. In grain crops, plant growth regulators are applied to promote sturdier growth and reduce the risk of lodging. Chlormequat is the most common plant growth regulator. Maximum residue limits of chlormequat in food products are 10 mg/kg in oat and pear, 3 mg/kg in wheat and rye, and 0.5 mg/kg in milk. In Denmark, results from experiments with pigs in the late 1980s showed sows that display impaired reproduction, mainly impaired oestrus, when fed grain from crop treated with chlormequat. Subsequently, the advisory body to the Danish pig industry recommended limiting the use of grain (maximum 30% of diet energy) from crop treated with chlormequat given to breeding stock due to the risk of reproduction problems. More recently, experiments have been conducted to evaluate the influence of chlormequat-treated wheat crop on reproductive function in male and female mice. These experiments showed that epididymal spermatozoa from mice on feed or water containing chlormequat had compromised fertilizing competence in vitro, while reproduction in female mice was not compromised. The estimated intake of chlormequat in the pig (0.0023 mg/kg bw/day) and the mouse (0.024 mg/kg bw/day) experiments was below the acceptable daily intake of 0.05 mg/kg bw/day. Reports from the industry do not show any effects at these low levels.

  14. Plant growth promoting rhizobacteria: Beneficial effects for healthy ...

    African Journals Online (AJOL)

    Tuoyo Aghomotsegin

    2016-07-06

    Jul 6, 2016 ... bacteria colonize actively the root system of plants and improve their growth and yield. The PGPR use ..... nodules number, nodule dry weight, seed yield, nutrients availability ... (1984) observed a reduction of pH from 7 to 3. The study ..... microorganisms included Gram-positive bacteria such as. B. pumilus ...

  15. Cytokinin production by plant growth promoting rhizobacteria and selected mutants.

    Science.gov (United States)

    García de Salamone, I E; Hynes, R K; Nelson, L M

    2001-05-01

    One of the proposed mechanisms by which rhizobacteria enhance plant growth is through the production of plant growth regulators. Five plant growth promoting rhizobacterial (PGPR) strains produced the cytokinin dihydrozeatin riboside (DHZR) in pure culture. Cytokinin production by Pseudomonas fluorescens G20-18, a rifampicin-resistant mutant (RIF), and two TnphoA-derived mutants (CNT1, CNT2), with reduced capacity to synthesize cytokinins, was further characterized in pure culture using immunoassay and thin layer chromatography. G20-18 produced higher amounts of three cytokinins, isopentenyl adenosine (IPA), trans-zeatin ribose (ZR), and DHZR than the three mutants during stationary phase. IPA was the major metabolite produced, but the proportion of ZR and DHZR accumulated by CNT1 and CNT2 increased with time. No differences were observed between strain G20-18 and the mutants in the amounts of indole acetic acid synthesized, nor were gibberellins detected in supernatants of any of the strains. Addition of 10(-5) M adenine increased cytokinin production in 96- and 168-h cultures of strain G20-18 by approximately 67%. G20-18 and the mutants CNT1 and CNT2 may be useful for determination of the role of cytokinin production in plant growth promotion by PGPR.

  16. Plant Classification by Growth Form for Field Use.

    Science.gov (United States)

    Kemp, David M.

    1982-01-01

    A simple classification system for terrestrial plants is presented. The method is based on growth forms and avoids the need for identification to genus or species, although students could be encouraged to follow the work through to this level if appropriate. (Author/JN)

  17. 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.

  18. Isolation and characterization of plant growth-promoting rhizobacteria from wheat rhizosphere and their effect on plant growth promotion

    OpenAIRE

    Majeed, Afshan; Abbasi, M. Kaleem; Hameed, Sohail; Imran, Asma; Rahim, Nasir

    2015-01-01

    The present study was conducted to characterize the native plant growth promoting (PGP) bacteria from wheat rhizosphere and root-endosphere in the Himalayan region of Rawalakot, Azad Jammu and Kashmir (AJK), Pakistan. Nine bacterial isolates were purified, screened in vitro for PGP characteristics and evaluated for their beneficial effects on the early growth of wheat (Triticum aestivum L.). Among nine bacterial isolates, seven were able to produce indole-3- acetic acid in tryptophan-suppleme...

  19. Effects of Different Substrate Composition on Growth of Gesneriaceae Plants

    Institute of Scientific and Technical Information of China (English)

    Zhijing QIU; Chunqing ZOU; Zhengjun SHI; Yaoliang DAI; Ruixing XIE

    2014-01-01

    The cultivation experiment was carried out to investigate the effects of dif-ferent proportions of peat soil, perlite, vermiculite and yel ow mud on growth of Gesneriaceae species (Chirita gueilinensis, Sinningia speciosa, Lysionotus pauci-florus, Hemiboea henryi, Aeschynanthus acuminatus, Saintpaulia ionantha). The growth traits of each plant growing in 7 different matrix materials were investigated. The plant height, crown width and chlorophyl content of each plant were mea-sured. The results showed that the best substrate ratio was peat soil∶vermiculite=2∶1 for C. gueilinensis, L. pauciflorus and H. henryi; peat soil∶perlite∶vermiculite = 2∶1∶1 for S. ionantha; peat soil∶vermiculite∶yel ow mud=2∶1∶1 for S. speciosa; peat soil∶per-lite∶vermiculite∶yel ow mud=2∶1∶1∶1 for A. acuminatus.

  20. 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.

  1. 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.

  2. Baseload Nitrate Salt Central Receiver Power Plant Design Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Tilley, Drake [Abengoa Solar LLC, Lakewood, CO (United States); Kelly, Bruce [Abengoa Solar LLC, Lakewood, CO (United States); Burkholder, Frank [Abengoa Solar LLC, Lakewood, CO (United States)

    2014-12-12

    The objectives of the work were to demonstrate that a 100 MWe central receiver plant, using nitrate salt as the receiver coolant, thermal storage medium, and heat transport fluid in the steam generator, can 1) operate, at full load, for 6,400 hours each year using only solar energy, and 2) satisfy the DOE levelized energy cost goal of $0.09/kWhe (real 2009 $). To achieve these objectives the work incorporated a large range of tasks relating to many different aspects of a molten salt tower plant. The first Phase of the project focused on developing a baseline design for a Molten Salt Tower and validating areas for improvement. Tasks included a market study, receiver design, heat exchanger design, preliminary heliostat design, solar field optimization, baseline system design including PFDs and P&IDs and detailed cost estimate. The baseline plant met the initial goal of less than $0.14/kWhe, and reinforced the need to reduce costs in several key areas to reach the overall $0.09/kWhe goal. The major improvements identified from Phase I were: 1) higher temperature salt to improve cycle efficiency and reduce storage requirements, 2) an improved receiver coating to increase the efficiency of the receiver, 3) a large receiver design to maximize storage and meet the baseload hours objective, and 4) lower cost heliostat field. The second Phase of the project looked at advancing the baseline tower with the identified improvements and included key prototypes. To validate increasing the standard solar salt temperature to 600 °C a dynamic test was conducted at Sandia. The results ultimately proved the hypothesis incorrect and showed high oxide production and corrosion rates. The results lead to further testing of systems to mitigate the oxide production to be able to increase the salt temperature for a commercial plant. Foster Wheeler worked on the receiver design in both Phase I and Phase II looking at both design and lowering costs utilizing commercial fossil boiler

  3. 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

  4. 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

  5. Phosphorus mobilizing consortium Mammoth P™ enhances plant growth

    Directory of Open Access Journals (Sweden)

    Peter Baas

    2016-06-01

    Full Text Available 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.

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

    Directory of Open Access Journals (Sweden)

    W. H. Gera eHol

    2013-04-01

    Full Text Available 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 defence. This model organism has provided much understanding of the underlying molecular mechanisms of PGPR-induced plant defence. 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 defence 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 defence 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 defences 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

  7. 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.

  8. Plant growth promoting bacteria from Crocus sativus rhizosphere.

    Science.gov (United States)

    Ambardar, Sheetal; Vakhlu, Jyoti

    2013-12-01

    Present study deals with the isolation of rhizobacteria and selection of plant growth promoting bacteria from Crocus sativus (Saffron) rhizosphere during its flowering period (October-November). Bacterial load was compared between rhizosphere and bulk soil by counting CFU/gm of roots and soil respectively, and was found to be ~40 times more in rhizosphere. In total 100 bacterial isolates were selected randomly from rhizosphere and bulk soil (50 each) and screened for in-vitro and in vivo plant growth promoting properties. The randomly isolated bacteria were identified by microscopy, biochemical tests and sequence homology of V1-V3 region of 16S rRNA gene. Polyphasic identification categorized Saffron rhizobacteria and bulk soil bacteria into sixteen different bacterial species with Bacillus aryabhattai (WRF5-rhizosphere; WBF3, WBF4A and WBF4B-bulk soil) common to both rhizosphere as well as bulk soil. Pseudomonas sp. in rhizosphere and Bacillus and Brevibacterium sp. in the bulk soil were the predominant genera respectively. The isolated rhizobacteria were screened for plant growth promotion activity like phosphate solubilization, siderophore and indole acetic acid production. 50 % produced siderophore and 33 % were able to solubilize phosphate whereas all the rhizobacterial isolates produced indole acetic acid. The six potential PGPR showing in vitro activities were used in pot trial to check their efficacy in vivo. These bacteria consortia demonstrated in vivo PGP activity and can be used as PGPR in Saffron as biofertilizers.This is the first report on the isolation of rhizobacteria from the Saffron rhizosphere, screening for plant growth promoting bacteria and their effect on the growth of Saffron plant.

  9. 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.

  10. Forest Tree Growth as a Bioindicator of Pollution Abatement Systems at the Radford Army Ammunition Plant.

    Science.gov (United States)

    1982-01-14

    U-0Al C 0LIGNAPLTCGICIS P TT IY BLCSUG-EC FS1/ FOREST TREE GROWTH AS A BIOINDICATOR OF POLLUTION ABATEMENT SYS--ETC(I 𔃾- oa2 JAN 62 J M SKELLY. L W...947! FOREST TREE GROWTH AS A BIOINDICATOR OF POLLUTION ABATEMENT SYSTEMS AT THE RADFORD ARMY AMMUNITION PLANT Accession For FINAL REPORT Dr. John M...test potential bioindicator systems. x The study objectives of this research were: i’l) To determine if the pollution levels alone were responsible

  11. Radiation effects on organic materials in nuclear plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bruce, M B; Davis, M V

    1981-11-01

    A literature search was conducted to identify information useful in determining the lowest level at which radiation causes damage to nuclear plant equipment. Information was sought concerning synergistic effects of radiation and other environmental stresses. Organic polymers are often identified as the weak elements in equipment. Data on radiation effects are summarized for 50 generic name plastics and 16 elastomers. Coatings, lubricants, and adhesives are treated as separate groups. Inorganics and metallics are considered briefly. With a few noted exceptions, these are more radiation resistant than organic materials. Some semiconductor devices and electronic assemblies are extremely sensitive to radiation. Any damage threshold including these would be too low to be of practical value. With that exception, equipment exposed to less than 10/sup 4/ rads should not be significantly affected. Equipment containing no Teflon should not be significantly affected by 10/sup 5/ rads. Data concerning synergistic effects and radiation sensitization are discussed. The authors suggest correlations between the two effects.

  12. Waehlitz industrial power plant. Final report; Industriekraftwerk Waehlitz. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Krueger, M.; Winkler, F.; Becher, J.

    1997-05-01

    Combustion of high-sulphur lignite from the Central German mining area in an industrial power plant (combined heat and power) with a thermal capacity of 119 MW within the emission limits of the Technical Clean Air Directive (TA-Luft) and the 13th Federal Emissions Regulation (13. BImSchV). In addition to the legally required CO, SO{sub 2}, NO{sub x} and dust measurements, measuring equipment for continuous recording of N{sub 2}O under operating conditions has been installed. (orig.) [Deutsch] Verwertung schwefelreicher Braunkohle aus dem mitteldeutschen Bergbaurevier in einem Industriekraftwerk (Kraft-Waerme-Kopplung) mit einer thermischen Leistung von 119 MW unter den Bedingungen der Einhaltung der Forderungen der TA-Luft und der 13. BImSchV. Ausser den gesetzlich vorgeschriebenen Emissionsmessungen fuer CO, SO{sub 2}, NO{sub x}, Staub wurde eine Messstelle fuer einen kontinuierlichen Nachweis von N{sub 2}O unter Betriebsbedingungen installiert. (orig.)

  13. Study of practical cycles for geothermal power plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Eskesen, J.H.

    1977-04-01

    A comparison is made of the performance and cost of geothermal power cycles designed specifically, utilizing existing technology, to exploit the high temperature, high salinity resource at Niland and the moderate temperature, moderately saline resource at East Mesa in California's Imperial Valley. Only two kinds of cycles are considered in the analysis. Both employ a dual flash arrangement and the liberated steam is either utilized directly in a condensing steam turbine or used to heat a secondary working fluid in a closed Rankine (binary) cycle. The performance of several organic fluids was investigated for the closed cycle and the most promising were selected for detailed analysis with the given resource conditions. Results show for the temperature range investigated that if the noncondensible gas content in the brine is low, a dual flash condensing steam turbine cycle is potentially better in terms of resource utilization than a dual flash binary cycle. (The reverse is shown to be true when the brine is utilized directly for heat exchange.) It is also shown that despite the higher resource temperature, the performance of the dual flash binary cycle at Niland is degraded appreciably by the high salinity and its output per unit of brine flow is almost 20 percent lower than that of the steam turbine cycle at East Mesa. Turbine designs were formulated and costs established for power plants having a nominal generating capacity of 50 MW. Three cycles were analyzed in detail. At East Mesa a steam turbine and a binary cycle were compared. At Niland only the binary cycle was analyzed since the high CO/sub 2/ content in the brine precludes the use of a steam turbine there. In each case only the power island equipment was considered and well costs and the cost of flash separators, steam scrubbers and piping to the power plant boundary were excluded from the estimate.

  14. Effects of plant growth regulators on the growth and lipid accumulation of Nannochloropsis oculata (droop) Hibberd

    Science.gov (United States)

    Trinh, Cam Tu; Tran, Thanh Huong; Bui, Trang Viet

    2017-09-01

    Nannochloropsis oculata cells were grown in f/2 modified medium of Chiu et al. (2009) supplemented with the plant growth regulators in different concentrations. Lipid accumulation of N. oculata cells was evaluated by using Nile Red dye and Fiji Image J with Analyze Particles. Indole-3-acetic acid (IAA) stimulated the increase of cell density in rapid growth phase (day 6) at high concentration (0.75 mg/L) and in slow growth phase (day 10) at lower concentration (0.50 mg/L). IAA, gibberellic acid (GA3) and zeatin increased content of chlorophyll a, in particular, in f/2 modified medium supplemented with 0.5 mg/L zeatin at the 10th day of culture. Roles of plant growth regulators in growth and lipid accumulation of N. oculata were discussed.

  15. 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.

  16. 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.

  17. 75 FR 21394 - Endangered and Threatened Wildlife and Plants; Final Revised Critical Habitat for Hine's Emerald...

    Science.gov (United States)

    2010-04-23

    ... Revised Critical Habitat for Hine's Emerald Dragonfly (Somatochlora hineana); Final Rule #0;#0;Federal... Plants; Final Revised Critical Habitat for Hine's Emerald Dragonfly (Somatochlora hineana) AGENCY: Fish... (Service), are designating critical habitat for the Hine's emerald dragonfly (Somatochlora hineana) under...

  18. 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

  19. 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.

  20. Simulation model for plant growth in controlled environment systems

    Science.gov (United States)

    Raper, C. D., Jr.; Wann, M.

    1986-01-01

    The role of the mathematical model is to relate the individual processes to environmental conditions and the behavior of the whole plant. Using the controlled-environment facilities of the phytotron at North Carolina State University for experimentation at the whole-plant level and methods for handling complex models, researchers developed a plant growth model to describe the relationships between hierarchial levels of the crop production system. The fundamental processes that are considered are: (1) interception of photosynthetically active radiation by leaves, (2) absorption of photosynthetically active radiation, (3) photosynthetic transformation of absorbed radiation into chemical energy of carbon bonding in solube carbohydrates in the leaves, (4) translocation between carbohydrate pools in leaves, stems, and roots, (5) flow of energy from carbohydrate pools for respiration, (6) flow from carbohydrate pools for growth, and (7) aging of tissues. These processes are described at the level of organ structure and of elementary function processes. The driving variables of incident photosynthetically active radiation and ambient temperature as inputs pertain to characterization at the whole-plant level. The output of the model is accumulated dry matter partitioned among leaves, stems, and roots; thus, the elementary processes clearly operate under the constraints of the plant structure which is itself the output of the model.

  1. Overview of OVATE FAMILY PROTEINS, a novel class of plant-specific growth regulators

    Directory of Open Access Journals (Sweden)

    Shucai eWang

    2016-03-01

    Full Text Available OVATE FAMILY PROTEINS (OFPs are a class of proteins with a conserved OVATE domain. OVATE protein was first identified in tomato as a key regulator of fruit shape. OFPs are plant-specific proteins that are widely distributed in the plant kingdom including mosses and lycophytes. Transcriptional activity analysis of Arabidopsis OFPs (AtOFPs in protoplasts suggests that they act as transcription repressors. Functional characterization of OFPs from different plant species including Arabidopsis, rice, tomato, pepper and banana suggests that OFPs regulate multiple aspects of plant growth and development, which is likely achieved by interacting with different types of transcription factors including the KNOX and BELL classes, and/or directly regulating the expression of target genes such as Gibberellin 20 oxidase (GA20ox. Here, we examine how OVATE was originally identified, summarize recent progress in elucidation of the roles of OFPs in regulating plant growth and development, and describe possible mechanisms underpinning this regulation. Finally, we review potential new research directions that could shed additional light on the functional biology of OFPs in plants.

  2. Coumarin-related compounds as plant growth inhibitors from two rutaceous plants in Thailand.

    Science.gov (United States)

    Jiwajinda, S; Santisopasri, V; Ohigashi, H

    2000-02-01

    Chemical investigation of naturally occurring plant growth inhibitors from Rutaceous plants in Thailand led us to identify five 7-methoxycoumarins and one 5,7-dimethoxycoumarin from Murraya paniculata, and six furanocoumarins from Citrus aurantifolia. Of these compounds, murranganon senecioate (1) is a new natural compound found in M. paniculata. Minumicrolin (6) was found to be highly active against the 2nd leaf sheath elongation of rice seedlings.

  3. Planting geometry to optimize growth and productivity in faba bean (Vicia faba L.) and soil fertility.

    Science.gov (United States)

    Singh, A K; Bhatt, B P; Sundaram, P K; Gupta, A K; Singh, Deepak

    2013-01-01

    Faba bean (Vicia faba L.) responses to alteration of its ambient environment leads to certain modification in the crop phenology, yield attributes and economic yield. To know the extent and pattern of response by faba bean to alterations, a two year field experimentation was carried out with two crop establishment methods (i) flatbed planting (ii) raised bed planting, four planting geometry (i) 30 x 20 cm(ii) 30 x 30 cm (iii) 30 x 45 cm and (iv) 45X45cm and three seeding depth. All the treatment (two crop establishment methods, four planting geometry and three seeding depth) were combined together consisting twenty four treatments, were organized in factorial experiment in complete randomized block design (CRBD) with three replications. Data were recorded on growth and development; yield attributes and yield. Soil analysis was done and finally statistical tool were applied to come in to valid conclusion. Raised bed planting proves superior over flatbed in case of seed yield. Square planting architect with 30 cm apart prove better (3690.9 kg ha(-1)) than other tested planting geometry. Seeding at 10 cm depth showed, significant improvement in seed yield per plant and per ha over other two tested seeding depth. Phosphorus availability was significantly higher in raised bed planting (36.9 kg ha(-1)). However, available K (kg ha(-1)) was significantly influenced by planting geometry and seeding depth. It was maximum (155.2 kg ha(-1)) with 30 x 45 cm plant geometry, proved significantly higher than 30 x 20 cm and 30 x 30 cm and at par with 45 x 45 cm planting.

  4. Final environmental impact statement. Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    1980-10-01

    In accordance with the National Environmental Policy Act (NEPA) of 1969, the US Department of Energy (DOE) has prepared this document as environmental input to future decisions regarding the Waste Isolation Pilot Plant (WIPP), which would include the disposal of transuranic waste, as currently authorized. The alternatives covered in this document are the following: (1) Continue storing transuranic (TRU) waste at the Idaho National Engineering Laboratory (INEL) as it is now or with improved confinement. (2) Proceed with WIPP at the Los Medanos site in southeastern New Mexico, as currently authorized. (3) Dispose of TRU waste in the first available repository for high-level waste. The Los Medanos site would be investigated for its potential suitability as a candidate site. This is administration policy and is the alternative preferred by the DOE. (4) Delay the WIPP to allow other candidate sites to be evaluated for TRU-waste disposal. This environmental impact statement is arranged in the following manner: Chapter 1 is an overall summary of the analysis contained in the document. Chapters 2 and 4 set forth the objectives of the national waste-management program and analyze the full spectrum of reasonable alternatives for meeting these objectives, including the WIPP. Chapter 5 presents the interim waste-acceptance criteria and waste-form alternatives for the WIPP. Chapters 6 through 13 provide a detailed description and environmental analysis of the WIPP repository and its site. Chapter 14 describes the permits and approvals necessary for the WIPP and the interactions that have taken place with Federal, State, and local authorities, and with the general public in connection with the repository. Chapter 15 analyzes the many comments received on the DEIS and tells what has been done in this FEIS in response. The appendices contain data and discussions in support of the material in the text.

  5. BACA Project: geothermal demonstration power plant. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1982-12-01

    The various activities that have been conducted by Union in the Redondo Creek area while attempting to develop the resource for a 50 MW power plant are described. The results of the geologic work, drilling activities and reservoir studies are summarized. In addition, sections discussing the historical costs for Union's involvement with the project, production engineering (for anticipated surface equipment), and environmental work are included. Nineteen geothermal wells have been drilled in the Redondo Creek area of the Valles Caldera: a prominent geologic feature of the Jemez mountains consisting of Pliocene and Pleistocene age volcanics. The Redondo Creek area is within a complex longitudinal graben on the northwest flank of the resurgent structural dome of Redondo Peak and Redondo Border. The major graben faults, with associated fracturing, are geologically plausible candidates for permeable and productive zones in the reservoir. The distribution of such permeable zones is too erratic and the locations too imprecisely known to offer an attractive drilling target. Log analysis indicates there is a preferred mean fracture strike of N31W in the upper portion of Redondo Creek wells. This is approximately perpendicular to the major structure in the area, the northeast-striking Redondo Creek graben. The geothermal fluid found in the Redondo Creek reservoir is relatively benign with low brine concentrations and moderate H/sub 2/S concentrations. Geothermometer calculations indicate that the reservoir temperature generally lies between 500/sup 0/F and 600/sup 0/F, with near wellbore flashing occurring during the majority of the wells' production.

  6. The heavy metal ions (Cu2+, Zn2+, Cd+) toxic compounds influence on triticale plants growth

    Science.gov (United States)

    Brezoczki, V. M.; Filip, G. M.

    2017-05-01

    The presence of the heavy metals toxic compounds (CuSO4 · 5H2O, ZnSO4 · 7H2O and 3CdSO4·8H2O) in water and soil can be observed by their negative effects on the germination and growth process for different vegetable (barley, oat, maize) who are used for human and animal consumption. This paper it aims the determination of germination and growth inhibition negative effects for triticale plants in the heavy metals ions presence by ecotoxicological laboratory tests. The triticale plants was chosen for their different characteristics to the other grasses respectively: a very good resistance for a wide range of diseases, an accelerated growth and a very good tolerance for aluminum ions presents in acid soils. The determinations were conducted step by step, first, we put the triticale grains in contact with the heavy metal solutions with different concentration then for 3 days we noticed the triticale germination inhibition effects and finally we noticed the growth inhibition process for triticale plants respectively in 7th and 9th day from the start of the experiment. At the end of the tests we can conclude that the triticale roots have a very great sensibility to a CuSO4 solutions compared to the effects for their stalks. A positive effect for triticale stalks we can see for low CuSO4 solution concentrations thus for 5 mg Cu/l the growth is 19,44%. A positive effect for triticale roots it can see for low ZnSO4 solution concentrations so for 5 - 15 mg Zn/l the growth is 24,4%. In the presence of the CdSO4 solution all the processes are inhibited (germination and growth for triticale plants) even for a low concentrations for this toxic.

  7. Body growth considerations in age-specific dosimetry. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Eckerman, K.F.

    1993-09-30

    This report describes the manner in which the age-specific dosimetric calculations of the International Commission on Radiological Protection (ICRP) addressed changes in organ size that occur with age. The approach involves an interpolation of dosimetric information derived for six reference individuals using the inverse of the total body mass as the interpolation variable. An alternative formulation is investigated that employs a functional representation of the organ mass as a function of age in conjunction with an explicit formulation of the dosimetric factors in terms of organ mass. Using an exponential-logistic growth function as suggested by Walker, this report demonstrates, through application to the dosimetry of radioiodines in the thyroid, that the alternative formulation can be formulated and implemented. Although either approach provides a workable basis for age-specific dosimetry, it is clear that the functional representation of organ growth has some attractive features. However, without question, the major difficulty is the quality and quantity of data available to address the age- and gender-specific parameters in the dosimetric formulations.

  8. Reduced wind speed improves plant growth in a desert city.

    Directory of Open Access Journals (Sweden)

    Christofer Bang

    Full Text Available BACKGROUND: The often dramatic effects of urbanization on community and ecosystem properties, such as primary productivity, abundances, and diversity are now well-established. In most cities local primary productivity increases and this extra energy flows upwards to alter diversity and relative abundances in higher trophic levels. The abiotic mechanisms thought to be responsible for increases in urban productivity are altered temperatures and light regimes, and increased nutrient and water inputs. However, another abiotic factor, wind speed, is also influenced by urbanization and well known for altering primary productivity in agricultural systems. Wind effects on primary productivity have heretofore not been studied in the context of urbanization. METHODOLOGY/PRINCIPAL FINDINGS: We designed a field experiment to test if increased plant growth often observed in cities is explained by the sheltering effects of built structures. Wind speed was reduced by protecting Encelia farinosa (brittlebush plants in urban, desert remnant and outlying desert localities via windbreaks while controlling for water availability and nutrient content. In all three habitats, we compared E. farinosa growth when protected by experimental windbreaks and in the open. E. farinosa plants protected against ambient wind in the desert and remnant areas grew faster in terms of biomass and height than exposed plants. As predicted, sheltered plants did not differ from unprotected plants in urban areas where wind speed is already reduced. CONCLUSION/SIGNIFICANCE: Our results indicate that reductions in wind speed due to built structures in cities contribute to increased plant productivity and thus also to changes in abundances and diversity of higher trophic levels. Our study emphasizes the need to incorporate wind speed in future urban ecological studies, as well as in planning for green space and sustainable cities.

  9. Dynamic Plant-Plant-Herbivore Interactions Govern Plant Growth-Defence Integration

    NARCIS (Netherlands)

    Vries, de Jorad; Evers, Jochem B.; Poelman, Erik H.

    2017-01-01

    Plants downregulate their defences against insect herbivores upon impending competition for light. This has long been considered a resource trade-off, but recent advances in plant physiology and ecology suggest this mechanism is more complex. Here we propose that to understand why plants regulate an

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  11. 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.

  12. Growth-promotion of plants with depolymerized alginates by irradiation

    Science.gov (United States)

    Hien, Nguyen Quoc; Nagasawa, Naotsugu; Tham, Le Xuan; Yoshii, Fumio; Dang, Vo Huy; Mitomo, Hiroshi; Makuuchi, Keizo; Kume, Tamikazu

    2000-07-01

    Alginate has been degraded by gamma-ray irradiation from a Co-60 source in liquid state (aqueous solution) and in solid state (powder form). The irradiated alginate with a molecular weight less than 10 4 shows a strong effect on the growth-promotion of rice and peanut. Low concentration of degraded alginate from 4% solution irradiated at 100 kGy is effective for the growth-promotion of plants and the suitable concentrations are ca 50 ppm for rice and ca 100 ppm for peanut.

  13. Effects of New Plant Growth Regulators on Growth and Quality in Potato

    Directory of Open Access Journals (Sweden)

    Chen Weiyan

    2015-04-01

    Full Text Available This experiment aimed to explore the effects of new plant growth regulators on the growth and quality of potato, we conduct potato tubers with different concentrations of the regulators and cultivated in the seedling pot, with water as the control treatment. The results showed that sorbic amide (5%, sorbic amide quaternary ammonium salt (5%, Cinnamamide (5%, betaine Cinnamamide (5%, naphthalene dicarboxamide (5%, betaine naphthalenedicarboxamide (5% these 6 new regulators have good activity in improving and enhancing the content of chlorophyll, soluble protein, soluble sugar and free amino acids with 400 times dilution and 800 times dilution on potato seedling. At the same time, we compared the changes of the physiological indexes in different periods. As can be seen from the experiment, these 6 compounds have a strong role in promoting growth and improving the quality of the potato so that they can be called plant growth regulators.

  14. Plant development in space: Observations on root formation and growth

    Science.gov (United States)

    Levine, H. G.; Kann, R. P.; Krikorian, Abraham D.

    1990-01-01

    Root growth in space is discussed and observations on root production from plants flown as part of the Chromex project that were defined as to their origin, stage of development and physiological status, are presented. Roots were generated from fully differentiated, aseptically maintained individuals of Haplopappus gracilis (Compositae) under spaceflight conditions. Results are compared for tissue culture generated plantlets and comparably sized seedling clone individuals, both of which had their roots trimmed on Earth before they were loaded into NASA's plant growth unit and subjected to a 5 day shuttle flight (STS-29). Asepsis was maintained throughout the experiment. Overall root production was 40 to 50 percent greater under spaceflight conditions than during ground control tests. However, root formation slowed down towards the end of the flight. This decrease in new roots did not occur in the ground controls that sought to simulate flight except for microgravity.

  15. 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.

  16. Study of creep cavity growth for power plant lifetime assessment

    Energy Technology Data Exchange (ETDEWEB)

    Wu Rui; Sandstroem, Rolf

    2001-01-01

    This report aims to the sub project lifetime assessment by creep (livslaengdspredikteringar vid kryp), which is involved in the project package strength in high temperature power plant, KME 708. The physical creep damage includes mainly cavities and their development. Wu and Sandstroem have observed that cavity size increases linearly with increasing creep strain in a 12%Cr steel. Sandstroem has showed that, based on the relations between the nucleation and growth of creep cavities with creep strain, the physical creep damage can be modelled as a function of creep strain. In the present paper the growth of creep cavity radius R in relation to time t and strain {epsilon} in low alloy and 12%Cr steels as well as a Type 347 steel has been studied. The results exhibit that the power law cavity radius with creep time (R-t) and with creep strain (R-{epsilon}) relations are found for these materials at various testing conditions. The power law R-t and R-{epsilon} relations are in most cases dependent and independent on testing conditions, respectively. The empirical power law R-{epsilon} relations give a description of cavity evolution, which can be used for lifetime assessment. Experimental data have also been compared to the estimations by the classical models for cavity growth, including the power law growth due to Hancock, the diffusion growth due to Speight and Harris, the constrained diffusion growths due to Dyson and due to Rice and the enhanced diffusion growth due to Beere. It appears that the constraint diffusion growth models give a reasonable estimation of R-{epsilon} relation in many cases. The diffusion growth model is only applicable for limited cases where the power over t in R-t relation takes about 1/3. The power law and the enhanced diffusion models are found in most cases to overestimate the cavity growth.

  17. Aromatic fluorine compounds. VIII. Plant growth regulators and intermediates

    Science.gov (United States)

    Finger, G.C.; Gortatowski, M.J.; Shiley, R.H.; White, R.H.

    1959-01-01

    The preparation and properties of 41 fluorophenoxyacetic acids, 4 fluorophenoxypropionic acids, 2 fluorobenzoic acids, several indole derivatives, and a number of miscellaneous compounds are described. Data are given for many intermediates such as new fluorinated phenols, anisoles, anilines and nitrobenzenes. Most of the subject compounds are related to a number of well-known herbicides or plant growth regulators such as 2,4-D, 2,4,5-T and others.

  18. Microbial phytases in phosphorus acquisition and plant growth promotion

    OpenAIRE

    2011-01-01

    Phosphorus (P) is one of the major constituents in energy metabolism and biosynthesis of nucleic acids and cell membranes with an important role in regulation of a number of enzymes. Soil phosphorous is an important macronutrient for plant growth. Phosphorus deficiency in soil is a major problem for agricultural production. Total soil P occurs in either organic or in organic form. Phytic acid as phytate (salts of phytic acid) is the major form of organic phosphorus in soil and it is not readi...

  19. A hydroponic method for plant growth in microgravity

    Science.gov (United States)

    Wright, B. D.

    1985-01-01

    A hydroponic apparatus under development for long-term microgravity plant growth is described. The capillary effect root environment system (CERES) is designed to keep separate the nutrient and air flows, although both must be simultaneously available to the roots. Water at a pressure slightly under air pressure is allowed to seep into a plastic depression covered by a plastic screen and a porous membrane. A root in the air on the membrane outer surface draws the moisture through it. The laboratory model has a wire-based 1.241 mm mesh polyethylene screen and a filter membrane with 0.45 micron pores, small enough to prohibit root hair penetration. The design eliminates the need to seal-off the plant environment. Problems still needing attention include scaling up of the CERES size, controlling biofouling of the membrane, and extending the applications to plants without fibrous root systems.

  20. 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.

  1. Key Gaps for Enabling Plant Growth in Future Missions

    Science.gov (United States)

    Anderson, Molly; Motil, Brian; Barta, Dan; Fritsche, Ralph; Massa, Gioia; Quincy, Charlie; Romeyn, Matthew; Wheeler, Ray; Hanford, Anthony

    2017-01-01

    Growing plants to provide food or psychological benefits to crewmembers is a common vision for the future of human spaceflight, often represented in media and in serious concept studies. The complexity of controlled environment agriculture, and plant growth in microgravity have and continue to be the subject of dedicated scientific research. However, actually implementing these systems in a way that will be cost effective, efficient, and sustainable for future space missions is a complex, multi-disciplinary problem. Key questions exist in many areas: human medical research in nutrition and psychology, horticulture, plant physiology and microbiology, multi-phase microgravity fluid physics, hardware design and technology development, and system design, operations and mission planning. This paper describes key knowledge gaps identified by a multi-disciplinary working group within the National Aeronautics and Space Administration (NASA). It also begins to identify solutions to the simpler questions identified by the group based on work initiated in 2017. Growing plants to provide food or psychological benefits to crewmembers is a common vision for the future of human spaceflight, often represented in media and in serious concept studies. The complexity of controlled environment agriculture, and plant growth in microgravity have and continue to be the subject of dedicated scientific research. However, actually implementing these systems in a way that will be cost effective, efficient, and sustainable for future space missions is a complex, multi-disciplinary problem. Key questions exist in many areas: human medical research in nutrition and psychology, horticulture, plant physiology and microbiology, multi-phase microgravity fluid physics, hardware design and technology development, and system design, operations and mission planning. This paper describes key knowledge gaps identified by a multi-disciplinary working group within the National Aeronautics and Space

  2. Interspecific variation in the growth response of plants to an elevated ambient CO[sub 2] concentration

    Energy Technology Data Exchange (ETDEWEB)

    Poorter, H. (Department of Plant Ecology and Evolutionary Biology, Utrecht (Netherlands))

    1993-01-01

    The effect of a doubling in the atmospheric CO[sub 2] concentration on the growth of vegetative whole plants was investigated. In a compilation of literature sources, the growth stimulation of 156 plant species was found to be on average 37%. This enhancement is small compared to what could be expected on the basis of CO[sub 2] response curves of photosynthesis. The causes for this stimulation being so modest were investigated. Both the source-sink relationship and size constraints on growth can cause the growth-stimulating effect to be transient. Data on the 156 plant species were used to explore interspecific variation in the response of plants to high CO[sub 2]. The growth stimulation was larger for C3 species than for C4 plants. However the difference in growth stimulation is not as large as expected as C4 plants also significantly increased in weight (41% for C3 vs. 22% for C4). The few investigated CAM species were stimulated less in growth (15%) than the average C4 species. Within the group of C3 species, herbaceous crop plants responded more strongly than herbaceous wild species (58% vs. 35%) and potentially fast-growing wild species increased more in weight than slow-growing species (54% vs. 23%). C3 species capable of symbiosis with N[sub 2]-fixing organisms had higher growth stimulations compared to other C3 species. A common denominator in these 3 groups of more responsive C3 plants might be their large sink strength. Finally, there was some tendency for herbaceous dicots to show a larger response than monocots. Thus also within the group of C3 species differences exist in the growth response to high CO[sub 2]. 107 refs., 5 figs., 2 tabs.

  3. 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

  4. 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

  5. Minimising toxicity of cadmium in plants--role of plant growth regulators.

    Science.gov (United States)

    Asgher, Mohd; Khan, M Iqbal R; Anjum, Naser A; Khan, Nafees A

    2015-03-01

    A range of man-made activities promote the enrichment of world-wide agricultural soils with a myriad of chemical pollutants including cadmium (Cd). Owing to its significant toxic consequences in plants, Cd has been one of extensively studied metals. However, sustainable strategies for minimising Cd impacts in plants have been little explored. Plant growth regulators (PGRs) are known for their role in the regulation of numerous developmental processes. Among major PGRs, plant hormones (such as auxins, gibberellins, cytokinins, abscisic acid, jasmonic acid, ethylene and salicylic acid), nitric oxide (a gaseous signalling molecule), brassinosteroids (steroidal phytohormones) and polyamines (group of phytohormone-like aliphatic amine natural compounds with aliphatic nitrogen structure) have gained attention by agronomist and physiologist as a sustainable media to induce tolerance in abiotic-stressed plants. Considering recent literature, this paper: (a) overviews Cd status in soil and its toxicity in plants, (b) introduces major PGRs and overviews their signalling in Cd-exposed plants, (c) appraises mechanisms potentially involved in PGR-mediated enhanced plant tolerance to Cd and (d) highlights key aspects so far unexplored in the subject area.

  6. Plant hydraulic traits govern forest water use and growth

    Science.gov (United States)

    Matheny, Ashley; Bohrer, Gil; Fiorella, Rich; Mirfenderesgi, Golnazalsadat

    2016-04-01

    Biophysical controls at the leaf, stem, and root levels govern plant water acquisition and use. Suites of sometimes co-varying traits afford plants the ability to manage water stress at each of these three levels. We studied the contrasting hydraulic strategies of red oaks (Q. rubra) and red maples (A. rubrum) in northern Michigan, USA. These two species differ in stomatal regulation strategy and xylem architecture, and are thought to root at different depths. Water use was monitored through sap flux, stem water storage, and leaf water potential measurements. Depth of water acquisition was determined on the basis of stable oxygen and hydrogen isotopes from xylem water samples taken from both species. Fifteen years of bole growth records were used to compare the influence of the trees' opposing hydraulic strategies on carbon acquisition and growth. During non-limiting soil moisture conditions, transpiration from red maples typically exceeded that of red oak. However, during a 20% soil dry down, transpiration from red maples decreased by more than 80%, while transpiration from red oaks only fell by 31%. Stem water storage in red maple also declined sharply, while storage in red oaks remained nearly constant. The more consistent isotopic compositions of xylem water samples indicated that oaks can draw upon a steady, deep supply of water which red maples cannot access. Additionally, red maple bole growth correlated strongly with mean annual soil moisture, while red oak bole growth did not. These results indicate that the deeper rooting strategy of red oaks allowed the species to continue transpiration and carbon uptake during periods of intense soil water limitation, when the shallow-rooted red maples ceased transpiration. The ability to root deeply could provide an additional buffer against drought-induced mortality, which may permit some anisohydric species, like red oak, to survive hydrologic conditions that would be expected to favor survival of more isohydric

  7. Can We Predict How Earthworm Effects on Plant Growth Vary with Soil Properties?

    Directory of Open Access Journals (Sweden)

    Kam-Rigne Laossi

    2010-01-01

    Full Text Available Earthworms are usually assumed to enhance plant growth through different mechanisms which are now clearly identified. It is however difficult to determine their relative importance, and to predict a priori the strength and direction of the effects of a given earthworm species on a given plant. Soil properties are likely to be very influential in determining plant responses to earthworm activities. They are likely to change the relative strength of the various mechanisms involved in plant-earthworm interactions. In this paper, we review the different rationales used to explain changes in earthworm effect due to soil type. Then, we systematically discuss the effect of main soil characteristics (soil texture, OM, and nutrient contents on the different mechanisms allowing earthworm to influence plant growth. Finally, we identify the main shortcomings in our knowledge and point out the new experimental and meta-analytical approaches that need to be developed. An example of such a meta-analysis is given and means to go further are suggested. The result highlights a strong positive effect size in sandy soil and a weakly negative effect in clayey soil.

  8. Influence of growth regulators on plant growth, yield, and skin color of specialty potatoes

    Science.gov (United States)

    2,4-D has been used since the 1950’s to enhance color in red-skinned potatoes, but there is little research on the potential use of other plant growth regulators to improve tuber skin color in the wide range of specialty potatoes now available on the market. Field trials conducted at Parma, ID in 20...

  9. 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

  10. Influence of Nitrogen Sources and Plant Growth-Promoting Rhizobacteria Inoculation on Growth, Crude Fiber and Nutrient Uptake in Squash (Cucurbita moschata Duchesne ex Poir.) Plants

    OpenAIRE

    Alice I. TCHIAZE; Victor D. TAFFOUO; Henri FANKEM; Kenne, Martin; Régis BAZIRAMAKENGA; Ekodeck, Georges E.; Antoun, Hani

    2016-01-01

    Plant growth promoting rhizobacteria (PGPR, B) have immense potential application in sustainable agriculture as ecofriendly biofertilizers and biopesticides. In this study, the effects of three nitrogen (N) sources (NO3-, NH4+ and NO3NH4) and PGPR on growth, crude fiber and nutrient uptake were investigated in squash plants. Some growth parameters [root dry weight (RDW), shoot dry weight (SDW), total plant dry weight (PDW), number of leaves (NL), shoot length (SL), stem diameter (SD) and numb...

  11. Dynamics of seed-borne rice endophytes on early plant growth stages

    NARCIS (Netherlands)

    Hardoim, Pablo R.; Hardoim, Cristiane C. P.; van Overbeek, Leonard S.; van Elsas, Jan Dirk

    2012-01-01

    Bacterial endophytes are ubiquitous to virtually all terrestrial plants. With the increasing appreciation of studies that unravel the mutualistic interactions between plant and microbes, we increasingly value the beneficial functions of endophytes that improve plant growth and development. However,

  12. Dynamics of Seed-Borne Rice Endophytes on Early Plant Growth Stages

    NARCIS (Netherlands)

    Hardoim, P.R.; Hardoim, C.C.P.; Overbeek, van L.S.; Elsas, van J.D.

    2012-01-01

    Bacterial endophytes are ubiquitous to virtually all terrestrial plants. With the increasing appreciation of studies that unravel the mutualistic interactions between plant and microbes, we increasingly value the beneficial functions of endophytes that improve plant growth and development. However,

  13. EFFICIENCY OF PLANT GROWTH PROMOTING RHIZOBACTERIA (PGPR IN SUGARCANE

    Directory of Open Access Journals (Sweden)

    Antonio Morgado González

    2015-12-01

    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.

  14. 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.…

  15. Plant growth modeling at the JSC variable pressure growth chamber - An application of experimental design

    Science.gov (United States)

    Miller, Adam M.; Edeen, Marybeth; Sirko, Robert J.

    1992-01-01

    This paper describes the approach and results of an effort to characterize plant growth under various environmental conditions at the Johnson Space Center variable pressure growth chamber. Using a field of applied mathematics and statistics known as design of experiments (DOE), we developed a test plan for varying environmental parameters during a lettuce growth experiment. The test plan was developed using a Box-Behnken approach to DOE. As a result of the experimental runs, we have developed empirical models of both the transpiration process and carbon dioxide assimilation for Waldman's Green lettuce over specified ranges of environmental parameters including carbon dioxide concentration, light intensity, dew-point temperature, and air velocity. This model also predicts transpiration and carbon dioxide assimilation for different ages of the plant canopy.

  16. 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

  17. 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.

  18. Contributions of green light to plant growth and development.

    Science.gov (United States)

    Wang, Yihai; Folta, Kevin M

    2013-01-01

    Light passing through or reflected from adjacent foliage provides a developing plant with information that is used to guide specific genetic and physiological processes. Changes in gene expression underlie adaptation to, or avoidance of, the light-compromised environment. These changes have been well described and are mostly attributed to a decrease in the red light to far-red light ratio and/or a reduction in blue light fluence rate. In most cases, these changes rely on the integration of red/far-red/blue light signals, leading to changes in phytohormone levels. Studies over the last decade have described distinct responses to green light and/or a shift of the blue-green, or red-green ratio. Responses to green light are typically low-light responses, suggesting that they may contribute to the adaptation to growth under foliage or within close proximity to other plants. This review summarizes the growth responses in artificially manipulated light environments with an emphasis on the roles of green wavebands. The information may be extended to understanding the influence of green light in shade avoidance responses as well as other plant developmental and physiological processes.

  19. Chrysosporium pseudomerdarium produces gibberellins and promotes plant growth.

    Science.gov (United States)

    Hamayun, Muhammad; Khan, Sumera Afzal; Iqbal, Ilyas; Na, Chae-In; Khan, Abdul Latif; Hwang, Young-Hyun; Lee, Byung-Hyun; Lee, In-Jung

    2009-08-01

    We isolated 10 endophytic fungi from the roots of drought stressed soybean cultivar Hwangkeumkong and bioassayed on waito-c rice and soybean seedlings, in order to identify plant growth-promoting fungi. The fungal isolate D-2-1 provided the best result for plant height and biomass promotion as compared to wild type Gibberella fujikuroi. The D-2-1 culture filtrate (CF) was analyzed for the presence of gibberellins (GAs) and it was observed that all physiologically active GAs, especially gibberellic acid, were present in higher amounts (GA1, 0.24 ng/ml; GA3, 8.99 ng/ml; GA4, 2.58 ng/ml and GA7, 1.39 ng/ml) in conjunction with physiologically inactive GA5, GA9, GA15, GA19, and GA24. The fungal isolate D-2-1 was identified as a new strain of Chrysosporium pseudomerdarium through phylogenetic analysis of 18S rDNA sequence. Plant growth promotion and GAs production capacity of genus Chrysosporium have been reported for the first time in this study.

  20. Ion Deflection for Final Optics In Laser Inertial Fusion Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Abbott, R P; Latkowski, J F

    2006-11-17

    Left unprotected, both transmissive and reflective final optics in a laser inertial fusion power plant would quickly fail from melting, pulsed thermal stresses, or degradation of optical properties as a result of ion implantation. One potential option for mitigating this threat is to magnetically deflect the ions such that they are directed into a robust energy dump. In this paper we detail integrated studies that have been carried out to asses the viability of this approach for protecting final optics.

  1. Planting depth and rhizome size effects on below ground growth of licorice (Glycyrrhiza glabra L.

    Directory of Open Access Journals (Sweden)

    reza vali allah poor

    2009-06-01

    Full Text Available An experiment was carried out to evaluate the effects of planting depth and rhizome sizes on below ground growth of licorice (Glycyrrhiza glabra L. at research glasshouse of Mashhad Unversity in 2001. Factorial experiment containing 2 factors of planting depth (10, 20 and 40‌cm and rhizome sizes (1,2 and 3 buds or 4,7 and 10 gr with two replications in completely randomized block design was employed. Development of different variables during growing season including root and mother rhizome dry weight were measured.The highest and the lowest root dry weight (RDWhave been seen in depth of 20 and 40 cm‌, respectively. About 100 days after planting (DAP, RDW increaseed very slowly but thenafter increased faster‌. Rhizome of any sizes in‌ 20 cm, gave the highest RDW‌. Three-bud rhizomes produced the highest RDW and 1-bud rhizome produced the lowest. Mother rhizome dry weight (MRDW reduced untill 60 days after planting. After 75th day, MRDW has increased and all plants started to fill their mother rhizome and finally rhizome of depth 20 cm produced the highest dry weight. In 160 days after planting, mother rhizomes started to lose their weight‌. 1and 3 -bud mother rhizome produce the lowest and highest MRDW, respectively.

  2. Experimental determination of magnesium isotope fractionation during higher plant growth

    Science.gov (United States)

    Bolou-Bi, Emile B.; Poszwa, Anne; Leyval, Corinne; Vigier, Nathalie

    2010-05-01

    Two higher plant species (rye grass and clover) were cultivated under laboratory conditions on two substrates (solution, phlogopite) in order to constrain the corresponding Mg isotope fractionations during plant growth and Mg uptake. We show that bulk plants are systematically enriched in heavy isotopes relative to their nutrient source. The Δ 26Mg plant-source range from 0.72‰ to 0.26‰ for rye grass and from 1.05‰ to 0.41‰ for clover. Plants grown on phlogopite display Mg isotope signatures (relative to the Mg source) ˜0.3‰ lower than hydroponic plants. For a given substrate, rye grass display lower δ 26Mg (by ˜0.3‰) relative to clover. Magnesium desorbed from rye grass roots display a δ 26Mg greater than the nutrient solution. Adsorption experiments on dead and living rye grass roots also indicate a significant enrichment in heavy isotopes of the Mg adsorbed on the root surface. Our results indicate that the key processes responsible for heavy isotope enrichment in plants are located at the root level. Both species also exhibit an enrichment in light isotopes from roots to shoots (Δ 26Mg leaf-root = -0.65‰ and -0.34‰ for rye grass and clover grown on phlogopite respectively, and Δ 26Mg leaf-root of -0.06‰ and -0.22‰ for the same species grown hydroponically). This heavy isotope depletion in leaves can be explained by biological processes that affect leaves and roots differently: (1) organo-Mg complex (including chlorophyll) formation, and (2) Mg transport within plant. For both species, a positive correlation between δ 26Mg and K/Mg was observed among the various organs. This correlation is consistent with the link between K and Mg internal cycles, as well as with formation of organo-magnesium compounds associated with enrichment in heavy isotopes. Considering our results together with the published range for δ 26Mg of natural plants and rivers, we estimate that a significant change in continental vegetation would induce a change of

  3. The Effect of Plant Growth Promoting Bacteria on Transplants Growth and Lettuce Yield in Organic Production

    Directory of Open Access Journals (Sweden)

    Szczech Magdalena

    2016-12-01

    Full Text Available Application of beneficial bacterial strain B125 (Enterobacter sp. and strain PZ9 (Bacillus sp. in lettuce transplants production significantly enhanced seed germination and plant biomass. The best effect was obtained when the mixture of B125 and PZ9 was used. Combined application of these bacteria significantly increased transplants biomass, which was about 45% higher than that in the control. However, after planting these transplants in organic field, generally, there were no differences in yield and nutrient content in plants treated and not treated with the bacteria, except for nitrogen and vitamin C. The lettuce grown from transplants treated with bacterial mixture B125 + PZ9 contained significantly higher nitrogen than plants from other treatments. Opposite to nitrogen, bacterial applications decreased the amount of vitamin C. The growth and organic lettuce composition was affected by planting time. The yield was higher in spring, but the concentration of nutrients in these plants was lower than that in plants harvested in autumn. Climatic and light conditions in the late season were the reasons for increased dry matter content, minerals, phenolic compounds, and vitamin C, as well as high concentration of nitrates.

  4. 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

  5. Isolation and characterization of plant growth-promoting rhizobacteria from wheat rhizosphere and their effect on plant growth promotion

    Directory of Open Access Journals (Sweden)

    M. Kaleem eABBASI

    2015-03-01

    Full Text Available AbstractThe present study was conducted to characterize the native plant growth promoting bacteria from wheat rhizosphere and root-endosphere in the Himalayan region of Rawalakot, Azad Jammu and Kashmir (AJK, Pakistan. Nine bacterial isolates were purified, screened in vitro for plant growth promoting (PGP characteristics and evaluated for their beneficial effects on the early growth of wheat (Triticum aestivum L.. Among nine bacterial isolates, seven were able to produce indole-3- acetic acid in tryptophan-supplemented medium; seven were nitrogen fixer, and four were able to solubilize inorganic phosphate in vitro. Four different morphotypes were genotypically identified based on IGS-RFLP fingerprinting and representative of each morphotype was identified by 16S rRNA gene sequencing analysis except Gram positive putative Bacillus sp. Based on 16S rRNA gene sequence analysis, bacterial isolates AJK–3 and AJK-9 showing multiple PGP-traits were identified as Stenotrophomonas spp. while AJK-7 showed equal homologies to Acetobacter pasteurianus and Stenotrophomonas specie. Plant inoculation studies indicated that these PGPR strains provided a significant increase in shoot and root length, and shoot and root biomass. A significant increase in shoot N contents (up to 76% and root N contents (up to 32% was observed over the un-inoculated control. The study indicates the potential of these PGPR for inoculums production or biofertilizers for enhancing growth and nutrient content of wheat and other crops under field conditions. The study is the first report of wheat associated bacterial diversity in the Himalayan region of Rawalakot, AJK.

  6. Isolation and characterization of plant growth-promoting rhizobacteria from wheat rhizosphere and their effect on plant growth promotion.

    Science.gov (United States)

    Majeed, Afshan; Abbasi, M Kaleem; Hameed, Sohail; Imran, Asma; Rahim, Nasir

    2015-01-01

    The present study was conducted to characterize the native plant growth promoting (PGP) bacteria from wheat rhizosphere and root-endosphere in the Himalayan region of Rawalakot, Azad Jammu and Kashmir (AJK), Pakistan. Nine bacterial isolates were purified, screened in vitro for PGP characteristics and evaluated for their beneficial effects on the early growth of wheat (Triticum aestivum L.). Among nine bacterial isolates, seven were able to produce indole-3- acetic acid in tryptophan-supplemented medium; seven were nitrogen fixer, and four were able to solubilize inorganic phosphate in vitro. Four different morphotypes were genotypically identified based on IGS-RFLP fingerprinting and representative of each morphotype was identified by 16S rRNA gene sequencing analysis except Gram-positive putative Bacillus sp. Based on 16S rRNA gene sequence analysis, bacterial isolates AJK-3 and AJK-9 showing multiple PGP-traits were identified as Stenotrophomonas spp. while AJK-7 showed equal homologies to Acetobacter pasteurianus and Stenotrophomonas specie. Plant inoculation studies indicated that these Plant growth-promoting rhizobacteria (PGPR) strains provided a significant increase in shoot and root length, and shoot and root biomass. A significant increase in shoot N contents (up to 76%) and root N contents (up to 32%) was observed over the un-inoculated control. The study indicates the potential of these PGPR for inoculums production or biofertilizers for enhancing growth and nutrient content of wheat and other crops under field conditions. The study is the first report of wheat associated bacterial diversity in the Himalayan region of Rawalakot, AJK.

  7. Phosphate solubilizing bacteria and their role in plant growth promotion.

    Science.gov (United States)

    Rodríguez, H; Fraga, R

    1999-10-01

    The use of phosphate solubilizing bacteria as inoculants simultaneously increases P uptake by the plant and crop yield. Strains from the genera Pseudomonas, Bacillus and Rhizobium are among the most powerful phosphate solubilizers. The principal mechanism for mineral phosphate solubilization is the production of organic acids, and acid phosphatases play a major role in the mineralization of organic phosphorous in soil. Several phosphatase-encoding genes have been cloned and characterized and a few genes involved in mineral phosphate solubilization have been isolated. Therefore, genetic manipulation of phosphate-solubilizing bacteria to improve their ability to improve plant growth may include cloning genes involved in both mineral and organic phosphate solubilization, followed by their expression in selected rhizobacterial strains. Chromosomal insertion of these genes under appropriate promoters is an interesting approach.

  8. 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.

  9. Predicting Plant Performance Under Simultaneously Changing Environmental Conditions-The Interplay Between Temperature, Light, and Internode Growth.

    Science.gov (United States)

    Kahlen, Katrin; Chen, Tsu-Wei

    2015-01-01

    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 modeling temperature effects on plant development and growth is discussed.

  10. Distribution System Optimization Planning Based on Plant Growth Simulation Algorithm

    Institute of Scientific and Technical Information of China (English)

    WANG Chun; CHENG Hao-zhong; HU Ze-chun; WANG Yi

    2008-01-01

    An approach for the integrated optimization of the construction/expansion capacity of high-voltage/medium-voltage (HV/MV) substations and the configuration of MV radial distribution network was presented using plant growth simulation algorithm (PGSA). In the optimization process, fixed costs correspondent to the investment in lines and substations and the variable costs associated to the operation of the system were considered under the constraints of branch capacity, substation capacity and bus voltage. The optimization variables considerably reduce the dimension of variables and speed up the process of optimizing. The effectiveness of the proposed approach was tested by a distribution system planning.

  11. Hierarchical Helical Order in the Twisted Growth of Plant Organs

    Science.gov (United States)

    Wada, Hirofumi

    2012-09-01

    The molecular and cellular basis of left-right asymmetry in plant morphogenesis is a fundamental issue in biology. A rapidly elongating root or hypocotyl of twisting mutants of Arabidopsis thaliana exhibits a helical growth with a handedness opposite to that of the underlying cortical microtubule arrays in epidermal cells. However, how such a hierarchical helical order emerges is currently unknown. We propose a model for investigating macroscopic chiral asymmetry in Arabidopsis mutants. Our elastic model suggests that the helical pattern observed is a direct consequence of the simultaneous presence of anisotropic growth and tilting of cortical microtubule arrays. We predict that the root helical pitch angle is a function of the microtubule helical angle and elastic moduli of the tissues. The proposed model is versatile and is potentially important for other biological systems ranging from protein fibrous structures to tree trunks.

  12. Dwarfing effects of plant growth regulators on narcissi

    Institute of Scientific and Technical Information of China (English)

    RENXu-qin; LIANGHong-wei; CHENBo-qing; JIMei-yun

    2003-01-01

    The effects of four kinds of plant growth regulators with different concentrations on narcissi were studied in 2001.The results showed that the regulators could inhibit the growths of height and leaves of narcissi. Of the four regulators, the dwarfing effects of paclobatrazol (PP333) and uniconazole (S3307) on narcissi were better than those of chlorocholine (CCC) and dimethyl amino-sussinamic acid (B9). All of the regulators did not have significant effect on the root length. Moreover, the time of flowering was later for the narcissi treated with regulators than that of the control to a certain extent, and the range delayed was from 2 days to 19 days. The correlation analysis results showed that there was a significant correlation between the time of flowering and the concentrations of regulators. The ornament value of narcissi was obviously improved by using the regulators.

  13. Pochonia chlamydosporia promotes the growth of tomato and lettuce plants

    Directory of Open Access Journals (Sweden)

    Rosangela Dallemole-Giaretta

    2015-10-01

    Full Text Available The fungus Pochonia chlamydosporia is one of the most studied biological agents used to control plant-parasitic nematodes. This study found that the isolates Pc-3, Pc-10 and Pc-19 of this fungus promote the growth of tomato and lettuce seedlings. The isolate Pc-19 colonized the rhizoplane of tomato seedlings in only 15 days and produced a large quantity of chlamydospores. This isolate was able to use cellulose as a carbon source, in addition to glucose and sucrose. Scanning electron microscopy (SEM revealed that hyphae of the P. chlamydosporia isolate Pc-10 penetrated the epidermal cells of the tomato roots. These three P. chlamydosporia isolates promote the growth of tomato and lettuce.

  14. 75 FR 52967 - Final Environmental Impact Statement and South Florida and Caribbean Parks Exotic Plant...

    Science.gov (United States)

    2010-08-30

    ... Palm Beach, Florida. A Notice of Intent to prepare an environmental impact statement (EIS) for South... National Park Service Final Environmental Impact Statement and South Florida and Caribbean Parks Exotic... environmental impact statement for the South Florida and Caribbean Parks Exotic Plant Management Plan....

  15. Paddy plants inoculated with PGPR show better growth physiology and nutrient content under saline condition

    Directory of Open Access Journals (Sweden)

    Yachana Jha

    2013-09-01

    Full Text Available The possible role of plant growth-promoting rhizobacteria (PGPR to alleviate salt stress during plant growth has been studied on paddy rice (Oryza sativa L. 'GJ-17' under greenhouse conditions; the study included growth parameters, mineral concentration, and antioxidant enzyme level. Salinity reduced plant growth, but PGPR inoculation reduced its harmful effect up to 1% salinity. Plants inoculated with PGPR under saline conditions showed 16% higher germination, 8% higher survival, 27% higher dry weight, and 31% higher plant height. Similarly, PGPR inoculated plants showed increased concentrations of N(26%, P (16%, K (31%, and reduced concentrations of Na (71% and Ca (36% as compared to non-inoculated control plants under saline conditions. Plants inoculated with PGPR under saline conditions also showed significant variations in antioxidant levels and growth physiology. Results suggested that inoculation with PGPR Bacillus pumilus and Pseudomonas pseudoalcaligenes in salt-stressed plants could help to alleviate salt stress in the paddy.

  16. Plant growth-promoting rhizobacteria affect the growth and nutrient uptake of Fraxinus americana container seedlings.

    Science.gov (United States)

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

    2013-05-01

    Plant growth-promoting rhizobacteria (PGPR) are important catalysts that regulate the functional properties of agricultural systems. However, there is little information on the effect of PGPR inoculation on the growth and nutrient accumulation of forest container seedlings. This study determined the effects of a growth medium inoculated with PGPR on the nutrient uptake, nutrient accumulation, and growth of Fraxinus americana container seedlings. PGPR inoculation with fertilizer increased the dry matter accumulation of the F. americana aerial parts with delayed seedling emergence time. Under fertilized conditions, the accumulation time of phosphorous (P) and potassium (K) in the F. americana aerial parts was 13 days longer due to PGPR inoculation. PGPR increased the maximum daily P and K accumulations in fertilized seedlings by 9.31 and 10.44 %, respectively, but had little impact on unfertilized ones. Regardless of fertilizer application, the root exudates, namely sugars, amino acids, and organic acids significantly increased because of PGPR inoculation. PGPR inoculation with fertilizer increased the root, shoot, and leaf yields by 19.65, 22.94, and 19.44 %, respectively, as well as the P and K contents by 8.33 and 10.60 %, respectively. Consequently, the N, P, and K uptakes increased by 19.85, 31.97, and 33.95 %, respectively. Hence, PGPR inoculation with fertilizer can be used as a bioenhancer for plant growth and nutrient uptake in forest container seedling nurseries.

  17. In-plant safety/relief valve discharge load test, Monticello Plant. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Buzek, E.A. (comp.)

    1977-08-01

    This document reports the results of the test program of safety/relief valve (SRV) discharge load phenomena through a ramshead discharge device, and the effects upon the Mark I primary containment torus structure of the Monticello Nuclear Power Plant. The objectives were to provide a data base for verifying/improving bubble pressure, water reflood and piping load analytical models, and to measure the structural response of the torus, SRV piping, supports and acceleration of the basement and pedestal.

  18. FASEB summer research conference on signal transduction in plants. Final report, June 16, 1996--June 21, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Lomax, T.L.; Quatrano, R.S.

    1996-12-31

    This is the program from the second FASEB conference on Signal Transduction in Plants. Topic areas included the following: environmental signaling; perception and transduction of light signals; signaling in plant microbe interactions; signaling in plant pathogen interactions; cell, cell communication; cytoskeleton, plasma membrane, and cellwall continuum; signaling molecules in plant growth and development I and II. A list of participants is included.

  19. FASEB summer research conference on signal transduction in plants. Final report, June 16, 1996--June 21, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Lomax, T.L.; Quatrano, R.S.

    1996-12-31

    This is the program from the second FASEB conference on Signal Transduction in Plants. Topic areas included the following: environmental signaling; perception and transduction of light signals; signaling in plant microbe interactions; signaling in plant pathogen interactions; cell, cell communication; cytoskeleton, plasma membrane, and cellwall continuum; signaling molecules in plant growth and development I and II. A list of participants is included.

  20. Assessment of water sources to plant growth in rice based cropping systems by stable water isotopes

    Science.gov (United States)

    Mahindawansha, Amani; Kraft, Philipp; Racela, Heathcliff; Breuer, Lutz

    2016-04-01

    Rice is one of the most water-consuming crops in the world. Understanding water source utilization of rice will help us to improve water use efficiency (WUE) in paddy management. The objectives of our study are to evaluate the isotopic compositions of surface ponded water, soil water, irrigation water, groundwater, rain water and plant water and based on stable water isotope signatures to evaluate the contributions of various water sources to plant growth (wet rice, aerobic rice and maize) together with investigating the contribution of water from different soil horizons for plant growth in different maturity periods during wet and dry seasons. Finally we will compare the water balances and crop yields in both crops during both seasons and calculate the water use efficiencies. This will help to identify the most efficient water management systems in rice based cropping ecosystems using stable water isotopes. Soil samples are collected from 9 different depths at up to 60 cm in vegetative, reproductive and matured periods of plant growth together with stem samples. Soil and plant samples are extracted by cryogenic vacuum extraction. Root samples are collected up to 60 cm depth from 10 cm intercepts leading calculation of root length density and dry weight. Groundwater, surface water, rain water and irrigation water are sampled weekly. All water samples are analyzed for hydrogen and oxygen isotope ratios (d18O and dD) using Los Gatos Research DLT100. Rainfall records, ground water level, surface water level fluctuations and the amount of water irrigated in each field will be measured during the sampling period. The direct inference approach which is based on comparing isotopic compositions (dD and d18O) between plant stem water and soil water will be used to determine water sources taken up by plant. Multiple-source mass balance assessment can provide the estimated range of potential contributions of water from each soil depth to root water uptake of a crop. These

  1. Selection and Assessment of Plant Growth-Promoting Rhizobacteria for Biological Control of Multiple Plant Diseases.

    Science.gov (United States)

    Liu, Ke; Newman, Molli; McInroy, John A; Hu, Chia-Hui; Kloepper, Joseph W

    2017-08-01

    A study was designed to screen individual strains of plant growth-promoting rhizobacteria (PGPR) for broad-spectrum disease suppression in vitro and in planta. In a preliminary screen, 28 of 196 strains inhibited eight different tested pathogens in vitro. In a secondary screen, these 28 strains showed broad spectrum antagonistic activity to six different genera of pathogens, and 24 of the 28 strains produced five traits reported to be related to plant growth promotion, including nitrogen fixation, phosphate solubilization, indole-3-acetic acid production, siderophore production, and biofilm formation. In advanced screens, the 28 PGPR strains selected in vitro were tested in planta for biological control of multiple plant diseases including bacterial spot of tomato caused by Xanthomonas axonopodis pv. vesicatoria, bacterial speck of tomato caused by Pseudomonas syringae pv. tomato, damping-off of pepper caused by Rhizoctonia solani, and damping-off of cucumber caused by Pythium ultimum. In all, 5 of the 28 tested strains significantly reduced three of the four tested diseases, and another 19 strains showed biological control to two tested diseases. To understand the observed broad-spectrum biocontrol capacity, antiSMASH was used to predict secondary metabolite clusters of selected strains. Multiple gene clusters encoding for secondary metabolites, e.g., bacillibactin, bacilysin, and microcin, were detected in each strain. In conclusion, selected individual PGPR strains showed broad-spectrum biocontrol activity to multiple plant diseases.

  2. 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.

  3. Plant growth in amended molybdenum mine waste rock.

    Science.gov (United States)

    Burney, Owen T; Redente, Edward F; Lambert, Charles E

    2017-04-01

    This greenhouse study examined the use of organic and inorganic soil amendments in waste rock material from the former Questa Molybdenum Mine in northern New Mexico to promote beneficial soil properties. Waste rock material was amended with 11 soil amendment treatments that included municipal composted biosolids, Biosol®, inorganic fertilizer, and two controls (pure waste rock and sand). Elymus trachycaulus and Robinia neomexicana growth performance and plant chemistry were assessed across all treatments over a period of 99 and 141 days, respectively. Even though waste rock material had more than 200 times the molybdenum concentration of native soils, adverse effects were not observed for either species. The two main limiting factors in this study were soil nutritional status and soil water retention. The biosolid amendment was found to provide the greatest buffer against these limiting factors due to significant increases in both nutrition and soil water retention. As a result, both species responded with the highest levels of biomass production and the least amount of required water demands. Use of organic amendments such as biosolids, even though short lived in the soil, may provide plants the necessary growth stimulus to become more resilient to the harsh conditions found on many mine reclamation sites.

  4. Bacterial strains from floodplain soils perform different plant-growth promoting processes and enhance cowpea growth

    Directory of Open Access Journals (Sweden)

    Elaine Martins da Costa

    2016-08-01

    Full Text Available ABSTRACT Certain nodulating nitrogen-fixing bacteria in legumes and other nodule endophytes perform different plant-growth promoting processes. The objective of this study was to evaluate 26 bacterial strains isolated from cowpea nodules grown in floodplain soils in the Brazilian savannas, regarding performance of plant-growth promoting processes and ability to enhance cowpea growth. We also identified these strains by 16S rRNA sequencing. The following processes were evaluated: free-living biological nitrogen fixation (BNF, solubilization of calcium, aluminum and iron phosphates and production of indole-3-acetic acid (IAA. The abilities to nodulate and promote cowpea growth were evaluated in Leonard jars. Partial sequencing of the 16S rRNA gene identified 60 % of the strains as belonging to genus Paenibacillus. The following four genera were also identified: Bacillus, Bradyrhizobium, Enterobacter and Pseudomonas. None of the strains fixed N2 free-living. Among the strains, 80 % solubilized Ca phosphate and one solubilized Al phosphate and none solubilized Fe phosphate. The highest IAA concentrations (52.37, 51.52 and 51.00 μg mL−1 were obtained in the 79 medium with tryptophan by Enterobacter strains UFPI B5-7A, UFPI B5-4 and UFPI B5-6, respectively. Only eight strains nodulated cowpea, however, all increased production of total dry matter. The fact that the strains evaluated perform different biological processes to promote plant growth indicates that these strains have potential use in agricultural crops to increase production and environmental sustainability.

  5. Copper-resistant bacteria enhance plant growth and copper phytoextraction.

    Science.gov (United States)

    Yang, Renxiu; Luo, Chunling; Chen, Yahua; Wang, Guiping; Xu, Yue; Shen, Zhenguo

    2013-01-01

    In this study, we investigated the role of rhizospheric bacteria in solubilizing soil copper (Cu) and promoting plant growth. The Cu-resistant bacterium DGS6 was isolated from a natural Cu-contaminated soil and was identified as Pseudomonas sp. DGS6. This isolate solubilized Cu in Cu-contaminated soil and stimulated root elongation of maize and sunflower. Maize was more sensitive to inoculation with DGS6 than was sunflower and exhibited greater root elongation. In pot experiment, inoculation with DGS6 increased the shoot dry weight of maize by 49% and sunflower by 34%, and increased the root dry weight of maize by 85% and sunflower by 45%. Although the concentrations of Cu in inoculated and non-inoculated seedlings did not differ significantly, the total accumulation of Cu in the plants increased after inoculation. DGS6 showed a high ability to solubilize P and produce iron-chelating siderophores, as well as significantly improved the accumulation of P and Fe in both maize and sunflower shoots. In addition, DGS6 produced indole-3-acetic acid (IAA) and ACC deaminase, which suggests that it may modulate ethylene levels in plants. The bacterial strain DGS6 could be a good candidate for re-vegetation of Cu-contaminated sites. Supplemental materials are available for this article. Go to the publisher's online edition of International Journal of Phytoremediation to view the supplemental file.

  6. 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

    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 ph

  7. 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 o

  8. 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

  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

    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. 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.

    Rockwool, as an inert medium covered or bagged with polyethylene film, can be effectively used for plant culture in space station. 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.

  11. 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.

  12. Mechanism of Growth Enhancement of Plants Induced by Active Species in Plasmas

    Science.gov (United States)

    Watanabe, Satoshi; Ono, Reoto; Hayashi, Nobuya

    2015-09-01

    Plant growth enhances when seeds are irradiated by plasma. However the mechanism of the growth enhancement by plasma has not been clarified. In this study, growth enhancement of plants using various active species and variation of plant cells are investigated. RF plasma is generated under conditions where pressure is 60 Pa and input electrical power is 60 W. Irradiation period varies from 0 (control) to 75 min. Air plasma shows maximum growth of plants with irradiation period of 60 min on the other hand, oxygen plasma shows the maximum growth with irradiation period of 15 min. From change of gaseous species and pressure dependence, growth enhancing factor is expected to be active oxygen species produced in plasma. According to gene expression analysis of Arabidopsis, there are two speculated mechanism of plant growth enhancement. The first is acceleration of cell cycle by gene expressions of photosynthesis and glycolytic pathway, and the second is increase of cell size via plant hormone production.

  13. [The effect of soil inoculation with microbial pesticide destructors on plant growth and development].

    Science.gov (United States)

    Lisina, T O; Garan'kina, N G; Kruglov, Iu V

    2001-01-01

    Soil inoculation with liquid cultures of Bacillus megaterium 501 and Exophiala nigrum A-29 capable of degrading several organophosphorus pesticides accelerated growth and development of experimental plants, formation of their generative organs, and improved their productivity. This was particularly observed under stress plant growth conditions on phytotoxic peach substrates. The microorganisms inoculated can probably degrade phytotoxins present in soils, thereby favoring the plant development.

  14. Genome Sequence of the Banana Plant Growth-Promoting Rhizobacterium Pseudomonas fluorescens PS006.

    Science.gov (United States)

    Gamez, Rocío M; Rodríguez, Fernando; Ramírez, Sandra; Gómez, Yolanda; Agarwala, Richa; Landsman, David; Mariño-Ramírez, Leonardo

    2016-05-05

    Pseudomonas fluorescens is a well-known plant growth-promoting rhizobacterium (PGPR). We report here the first whole-genome sequence of PGPR P. fluorescens evaluated in Colombian banana plants. The genome sequences contains genes involved in plant growth and defense, including bacteriocins, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, and genes that provide resistance to toxic compounds.

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

    OpenAIRE

    Neyser De La Torre-Ruiz; Víctor Manuel Ruiz-Valdiviezo; Clara Ivette Rincón-Molina; Martha Rodríguez-Mendiola; Carlos Arias-Castro; Federico Antonio Gutiérrez-Miceli; Héctor Palomeque-Dominguez; Reiner Rincón-Rosales

    2016-01-01

    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 rRN...

  16. Plant-microbe interactions promoting plant growth and health: perspectives for controlled use of microorganisms in agriculture.

    Science.gov (United States)

    Berg, Gabriele

    2009-08-01

    Plant-associated microorganisms fulfill important functions for plant growth and health. Direct plant growth promotion by microbes is based on improved nutrient acquisition and hormonal stimulation. Diverse mechanisms are involved in the suppression of plant pathogens, which is often indirectly connected with plant growth. Whereas members of the bacterial genera Azospirillum and Rhizobium are well-studied examples for plant growth promotion, Bacillus, Pseudomonas, Serratia, Stenotrophomonas, and Streptomyces and the fungal genera Ampelomyces, Coniothyrium, and Trichoderma are model organisms to demonstrate influence on plant health. Based on these beneficial plant-microbe interactions, it is possible to develop microbial inoculants for use in agricultural biotechnology. Dependent on their mode of action and effects, these products can be used as biofertilizers, plant strengtheners, phytostimulators, and biopesticides. There is a strong growing market for microbial inoculants worldwide with an annual growth rate of approximately 10%. The use of genomic technologies leads to products with more predictable and consistent effects. The future success of the biological control industry will benefit from interdisciplinary research, e.g., on mass production, formulation, interactions, and signaling with the environment, as well as on innovative business management, product marketing, and education. Altogether, the use of microorganisms and the exploitation of beneficial plant-microbe interactions offer promising and environmentally friendly strategies for conventional and organic agriculture worldwide.

  17. High-Throughput Growth Prediction for Lactuca sativa L. Seedlings Using Chlorophyll Fluorescence in a Plant Factory with Artificial Lighting.

    Science.gov (United States)

    Moriyuki, Shogo; Fukuda, Hirokazu

    2016-01-01

    Poorly grown plants that result from differences in individuals lead to large profit losses for plant factories that use large electric power sources for cultivation. Thus, identifying and culling the low-grade plants at an early stage, using so-called seedlings diagnosis technology, plays an important role in avoiding large losses in plant factories. In this study, we developed a high-throughput diagnosis system using the measurement of chlorophyll fluorescence (CF) in a commercial large-scale plant factory, which produces about 5000 lettuce plants every day. At an early stage (6 days after sowing), a CF image of 7200 seedlings was captured every 4 h on the final greening day by a high-sensitivity CCD camera and an automatic transferring machine, and biological indices were extracted. Using machine learning, plant growth can be predicted with a high degree of accuracy based on biological indices including leaf size, amount of CF, and circadian rhythms in CF. Growth prediction was improved by addition of temporal information on CF. The present data also provide new insights into the relationships between growth and temporal information regulated by the inherent biological clock.

  18. Biochar treatment resulted in a combined effect on soybean growth promotion and a shift in plant growth promoting rhizobacteria

    Directory of Open Access Journals (Sweden)

    Dilfuza eEgamberdieva

    2016-02-01

    Full Text Available The application of biochar to soil is considered to have the potential for long-term soil carbon sequestration, as well as for improving plant growth and suppressing soil pathogens. In our study we evaluated the effect of biochar on the plant growth of soybeans, as well as on the composition of root-associated bacteria with plant growth promoting traits. Two types of biochar, namely, maize biochar (MBC, wood biochar (WBC, and hydrochar (HTC were used for pot experiments to monitor plant growth. Soybean plants grown in soil amended with HTC char (2% showed the best performance and were collected for isolation and further characterization of root-associated bacteria for multiple plant growth promoting traits.Only HTC char amendment resulted in a statistically significant increase in the root and shoot dry weight of soybeans. Interestingly, rhizosphere isolates from HTC char amended soil showed higher diversity than the rhizosphere isolates from the control soil. In addition, a higher proportion of isolates from HTC char amended soil compared with control soil was found to express plant growth promoting properties and showed antagonistic activity against one or more phytopathogenic fungi. Our study provided evidence that improved plant growth by biochar incorporation into soil results from the combination of a direct effect that is dependent on the type of char and a microbiome shift in root-associated beneficial bacteria.

  19. 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.

  20. The Effect of Bio-Fertilizers on Plant Growth and Growth Rate of Grafted Avocado (Persea americana Mill.

    Directory of Open Access Journals (Sweden)

    Lazarus Agus Sukamto

    2014-01-01

    Full Text Available Avocado (Persea americana Mill. is considered the most nutritious of all fruits. Avocado fruit contain high unsaturated fat, protein, and energy. It could be eaten fresh for food, drinks, cooking, and cosmetics. Recently, it has become a significant commodity in international trade. Indonesia is the 2nd avocado producing country, but only little quantity of avocado fruits could be exported. The farmers usually grow avocado plants from the seeds, without proper fertilizers in their backyards or small gardens. The problems could be solved by using grafted plants, proper fertilizers, and growing in a large scale of areas. This research was conducted to find out the effect of two liquid bio-fertilizers namely Mega Rhizo and Beyonic StarTmik on the plant growth and growth rate of grafted avocado plants. Some plant growths and growth rates of grafted avocado were influenced significantly by genotype accession, kind of bio-fertilizer, and weather (temperature.  Plant growth and growth rate of most avocado accessions were not significant differences to bio-fertilizer applications, but some avocado accessions on certain months were significant differently. Growth rate ranks of plant height based on accession were no. 10, 28, 13, 1, 5, 2, and 14 consecutively. Those of canopy width were no. 28, 10, 1, 2, 14, 5, and 13 consecutively. Those of trunk diameters were no. 28, 10, 2, 5, 1, 13, and 14 consecutively. All growth rate ranks based on bio-fertilizer were Mega Rhizo, Beyonic StarTmik, and control consecutively.

  1. 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.

  2. A method of variable spacing for controlled plant growth systems in spaceflight and terrestrial agriculture applications

    Science.gov (United States)

    Knox, J.

    1986-01-01

    A higher plant growth system for Controlled Ecological Life Support System (CELSS) applications is described. The system permits independent movement of individual plants during growth. Enclosed within variable geometry growth chambers, the system allocates only the volume required by the growing plants. This variable spacing system maintains isolation between root and shoot environments, providing individual control for optimal growth. The advantages of the system for hydroponic and aeroponic growth chambers are discussed. Two applications are presented: (1) the growth of soybeans in a space station common module, and (2) in a terrestrial city greenhouse.

  3. Plant Growth Biostimulants, Dietary Feed Supplements and Cosmetics Formulated with Supercritical CO2 Algal Extracts

    Directory of Open Access Journals (Sweden)

    Izabela Michalak

    2017-01-01

    Full Text Available The review paper presents the use of algal extracts as safe and solvent-free components of plant growth biostimulants, dietary feed additives and cosmetics. Innovative technology that uses extracts obtained by supercritical CO2 extraction, as a method of isolation of biologically active compounds from algal biomass, is presented. An important part of the complete technology is the final formulation of the product. This enabled realization of the further step which was assessment of the utilitarian properties of the extract-based products. The extracts were analysed for the presence of biologically active molecules (e.g., plant hormones, polyphenols which provide useful properties such as antioxidant, antiviral, anti-inflammatory and antibacterial. The bio-products were tested in germination tests and underwent field trials to search for plant growth biostimulatory properties. Tests on animals (laying hens experiments were conducted to assess pro-health properties of new dietary feed supplement. Another application were cosmetic formulations (dermatological tests. The results of the application tests were very promising, however further studies are required for the registration of the products and successful implementation to the market.

  4. Plant Growth Biostimulants, Dietary Feed Supplements and Cosmetics Formulated with Supercritical CO₂ Algal Extracts.

    Science.gov (United States)

    Michalak, Izabela; Chojnacka, Katarzyna; Saeid, Agnieszka

    2017-01-03

    The review paper presents the use of algal extracts as safe and solvent-free components of plant growth biostimulants, dietary feed additives and cosmetics. Innovative technology that uses extracts obtained by supercritical CO₂ extraction, as a method of isolation of biologically active compounds from algal biomass, is presented. An important part of the complete technology is the final formulation of the product. This enabled realization of the further step which was assessment of the utilitarian properties of the extract-based products. The extracts were analysed for the presence of biologically active molecules (e.g., plant hormones, polyphenols) which provide useful properties such as antioxidant, antiviral, anti-inflammatory and antibacterial. The bio-products were tested in germination tests and underwent field trials to search for plant growth biostimulatory properties. Tests on animals (laying hens experiments) were conducted to assess pro-health properties of new dietary feed supplement. Another application were cosmetic formulations (dermatological tests). The results of the application tests were very promising, however further studies are required for the registration of the products and successful implementation to the market.

  5. Characterization of the bioactive metabolites from a plant growth-promoting rhizobacteria and their exploitation as antimicrobial and plant growth-promoting agents.

    Science.gov (United States)

    George, Emrin; Kumar, S Nishanth; Jacob, Jubi; Bommasani, Bhaskara; Lankalapalli, Ravi S; Morang, P; Kumar, B S Dileep

    2015-05-01

    A plant growth-promoting bacterial strain, PM 105, isolated from a tea plantation soil from the North Eastern region of India was identified as Pseudomonas aeruginosa through classical and 16S ribosomal DNA (rDNA) gene sequencing. Further studies with this strain confirmed broad spectrum antifungal activity against ten human and plant pathogenic fungal pathogens viz. Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Aspergillus tubingensis, Candida albicans, Colletotrichum gloeosporioides, Fusarium oxysporum, Pencillium expansum, Rhizoctonia solani, Trichophyton rubrum besides growth-promoting property in cowpea (Vigna unguiculata) and pigeon pea (Cajanus cajan). However, no antibacterial property was exhibited by this strain against the four test bacterial pathogens tested in agar overlay method. The crude bioactive metabolites produced by this strain were isolated with three different solvents that exhibited significant antimicrobial and plant growth-promoting activity. Chloroform extract recorded significant antimicrobial and plant growth-promoting activity. Three major compounds viz. 1-hydroxyphenazine, pyocyanin, and phenazine-1-carboxamide were purified and characterized from crude extracts of this strain by various spectral data. The purified compounds recorded prominent antimicrobial activity but failed to establish the plant growth promotion activity in test crop plants under gnotobiotic conditions. Pyocyanin recorded significant antimicrobial activity, and best activity was recorded against T. rubrum (29 mm), followed by P. expansum (28 mm). These results suggest the use of PM 105 as plant growth-promoting agent in crop plants after successful field trials.

  6. Melatonin enhances plant growth and abiotic stress tolerance in soybean plants.

    Science.gov (United States)

    Wei, Wei; Li, Qing-Tian; Chu, Ya-Nan; Reiter, Russel J; Yu, Xiao-Min; Zhu, Dan-Hua; Zhang, Wan-Ke; Ma, Biao; Lin, Qing; Zhang, Jin-Song; Chen, Shou-Yi

    2015-02-01

    Melatonin is a well-known agent that plays multiple roles in animals. Its possible function in plants is less clear. In the present study, we tested the effect of melatonin (N-acetyl-5-methoxytryptamine) on soybean growth and development. Coating seeds with melatonin significantly promoted soybean growth as judged from leaf size and plant height. This enhancement was also observed in soybean production and their fatty acid content. Melatonin increased pod number and seed number, but not 100-seed weight. Melatonin also improved soybean tolerance to salt and drought stresses. Transcriptome analysis revealed that salt stress inhibited expressions of genes related to binding, oxidoreductase activity/process, and secondary metabolic processes. Melatonin up-regulated expressions of the genes inhibited by salt stress, and hence alleviated the inhibitory effects of salt stress on gene expressions. Further detailed analysis of the affected pathways documents that melatonin probably achieved its promotional roles in soybean through enhancement of genes involved in cell division, photosynthesis, carbohydrate metabolism, fatty acid biosynthesis, and ascorbate metabolism. Our results demonstrate that melatonin has significant potential for improvement of soybean growth and seed production. Further study should uncover more about the molecular mechanisms of melatonin's function in soybeans and other crops.

  7. Advances in the application of plant growth-promoting rhizobacteria in phytoremediation of heavy metals.

    Science.gov (United States)

    Tak, Hamid Iqbal; Ahmad, Faheem; Babalola, Olubukola Oluranti

    2013-01-01

    . Although not yet widely applied, utilizing a plant-microbe partnership is now being recognized as an important tool to enhance successful phytoremediaton of metal-contaminated sites. Hence, soil microbes are essential to soil health and sustainability. The key to their usefulness is their close association with, and positive influence on, plant growth and function. To capitalize on the early success of this technique and to improve it, additional research is needed on successful colonization and survival of inoculums under field conditions, because there are vital for the success of this approach. In addition, the effects of the interaction of PGPR and plant root-mediated process on the metal mobilization in soil are required, to better elucidate the mechanism that underlines bacterial-assisted phytoremediation is important. Finally, applying PGPR-associated phytoremediation under field conditions is important, because, to date, only locally contaminated sites have been treated with this technique, by using microbes cultured in the laboratory.

  8. Multitrait plant growth promoting (PGP) rhizobacterial isolates from Brassica juncea rhizosphere : Keratin degradation and growth promotion.

    Science.gov (United States)

    Anwar, Mohmmad Shahbaz; Siddique, Mohammad Tahir; Verma, Amit; Rao, Yalaga Rama; Nailwal, Tapan; Ansari, Mohammad; Pande, Veena

    2014-01-01

    Plant growth promoting (PGP) rhizobacteria, a beneficial microbe colonizing plant roots, enhanced crop productivity and offers an attractive way to replace chemical fertilizers, pesticides, and supplements. The keratinous waste which comprises feathers, hairs, nails, skin and wool creates problem of solid waste management due to presence of highly recalcitrant keratin. The multi traits rhizobacteria effective to remove both keratine from the environment by producing keratinase enzyme and to eradicate the chemical fertilizer by providing different PGP activity is novel achievement. In the present study, the effective PM2 strain of PGPR was isolated from rhizospheric soil of mustard (Brassica juncea) field, Pantnagar and they were identified on the basis of different biochemical tests as belonging to Bacillus genera. Different plant growth promoting activity, feather degradation and keratinolytic activity was performed and found very effective toward all the parameters. Furthermore, the efficient strain PM2 was identified on the basis of 16s rRNA sequencing and confirmed as Bacillus cereus. The strain PM2 might be used efficiently for keratinous waste management and PGP activity. Therefore, the present study suggests that Bacillus cereus have multi traits activity which extremely useful for different PGP activity and biotechnological process involving keratin hydrolysis, feather biodegradation or in the leather industry.

  9. A soil irrigation method for experimental plant growth

    Science.gov (United States)

    Pop, M. N.; Soran, M. L.

    2015-12-01

    An irrigation method developed in order to ensure periodic wetting of several batches of soil, for experimental plant growth, is proposed. An experimental irrigation installation, intended to perform real-time soil moisturizing, by adding known quantities (preset for a certain batch of soil) of aqueous solutions has been built and tested. The prototype installation comprises six miniature pumps for water dosage, each meant to moisturize a batch of soil. Each pump is actuated from the mains power supply, with zero-crossing synchronization. The administrated quantity of aqueous solution is a multiple of the minimum volume, 0.2±0.01 ml of fluid. Due to its structure, the system allows the administration of different aqueous solutions for each batch of soil. Due to its modular construction the experimental installation can be expanded in order to ensure water disposal over an increased number of soil batches and the method may be suited also for micro irrigation systems.

  10. Chromium Resistant Bacteria: Impact on Plant Growth in Soil Microcosm

    Directory of Open Access Journals (Sweden)

    Sayel Hanane

    2014-07-01

    Full Text Available Three chromium resistant bacterial strains, Pseudomonas fluorescens PF28, Enterobacter amnigenus EA31 and Enterococcus gallinarum S34 isolated from tannery waste contaminated soil were used in this study. All strains could resist a high concentration of K2Cr2O7 that is up to 300 mg/L. The effect of these strains on clover plants (Trifolium campestre in the presence of two chromium salts CrCl3 and K2Cr2O7 was studied in soil microcosm. Application of chromium salts adversely affected seed germination, root and shoot length. Bacterial inoculation improved the growth parameters under chromate stress when compared with non inoculated respective controls. There was observed more than 50% reduction of Cr(VI in inoculated soil microcosms, as compared to the uninoculated soil under the same conditions. The results obtained in this study are significant for the bioremediation of chromate pollution.

  11. Photosynthetic Determinants of Growth in Maize Plants: Effects of Nitrogen Nutrition on Growth, Carbon Fixation and Photochemical Features

    OpenAIRE

    S. C., Huber; Tatsuo, SUGIYAMA; R.S, Alberte; Department of Agriculture, Agricultural Research Service; Department of Agricultural Chemistry, Faculty of Agriculture, Tohoku University; Department of Molecular Genetics and Cell Biology, The University of Chicago

    1989-01-01

    Maize (Zea mays L.) plants were grown in a greenhouse with different levels of nitrate-N (2 to 20 millimolar). Nitrogen nutrition had dramatic effects on plant growth and photosynthetic characteristics of mature leaves. Increasing nitrogen resulted in greater biomass production, shoot/root ratios, and rates of leaf expansion during the day. The elongating zone of high-N plants had higher activities (per gram fresh weight) of sucrose synthase and neutral invertase than low-N plants, suggesting...

  12. Seed Treatment with Auxins Modulates Growth and Ion Partitioning in Salt-stressed Wheat Plants

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Experiments were performed to determine whether seed priming with different concentrations (100, 150, and 200 mg/L) of auxins (indoleacetic acid (IAA), indolebutyric acid (IBA), or their precursor tryptophane (Trp)) could alter salinity induced perturbances in salicylic acid and ion concentrations and, hence, growth in wheat (Triticum aestivum L.) cultivars, namely M.H.-97 (salt intolerant) and Inqlab-91 (salt tolerant). Primed and non-primed seeds were sown in Petri dishes in a growth room, as well as in a field treated with 15 dS/m NaCl salinity. All priming agents, except IBA, increased the final germination percentage in both cultivars. The seedlings of either cultivar raised from Trp-treated seeds had greater dry biomass when under salt stress. In field experiments, Trp priming was much more effective in mediating the increase in grain yield,irrespective of the cultivar, under salt stress. The alleviatory effect of Trp was found to be associated with reduced uptake of Na+ in the roots and subsequent translocation to the shoots, as well as increased partitioning of Ca2+ in the roots of salt-stressed wheat plants. Plants of both cultivars raised from Trp- and IAA-treated seeds accumulated free salicylic acid in their leaves when under salt stress. Overall, the Trp priming-induced improvement in germination and the subsequent growth of wheat plants could be related to ion homeostasis when under salt stress. The possible involvement of salicylic acid in the Trp priming-induced better growth under conditions of salt stress is discussed.

  13. Utilization of {gamma}-irradiation technique on plant mutation breeding and plant growth regulation in Tokyo Metropolitan Isotope Research Center

    Energy Technology Data Exchange (ETDEWEB)

    Suda, Hirokatsu [Tokyo Metropolitan Isotope Research Center (Japan)

    1997-03-01

    During about 30-years, we have developed {gamma}-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 {gamma}-irradiation to plant mutation breeding, we often observed that plants irradiated by low dose of {gamma}-rays showed superior or inferior growth than the of non-irradiated plants. Now, we established the irradiation conditions of {gamma}-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)

  14. Disease resistance or growth: the role of plant hormones in balancing immune responses and fitness costs

    NARCIS (Netherlands)

    Denance, N.; Sanchez Vallet, A.; Goffner, D.; Molina, A.

    2013-01-01

    Plant growth and response to environmental cues are largely governed by phytohormones. The plant hormones ethylene, jasmonic acid, and salicylic acid (SA) play a central role in the regulation of plant immune responses. In addition, other plant hormones, such as auxins, abscisic acid (ABA), cytokini

  15. 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 at

  16. Disease resistance or growth: the role of plant hormones in balancing immune responses and fitness costs

    NARCIS (Netherlands)

    Denance, N.; Sanchez Vallet, A.; Goffner, D.; Molina, A.

    2013-01-01

    Plant growth and response to environmental cues are largely governed by phytohormones. The plant hormones ethylene, jasmonic acid, and salicylic acid (SA) play a central role in the regulation of plant immune responses. In addition, other plant hormones, such as auxins, abscisic acid (ABA), cytokini

  17. 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

  18. 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 at

  19. Antiphase light and temperature cycles disrupt rhythmic plant growth : the Arabidopsis jetlag

    NARCIS (Netherlands)

    Bours, R.M.E.H.

    2014-01-01

      Light and temperature are important determinants of plant growth and development. Plant elongation is stimulated by positively increasing differences between day and night temperature (+DIF, phased cycles). In contrast, a negative temperature difference (-DIF, antiphased cycles) reduces

  20. Antiphase light and temperature cycles disrupt rhythmic plant growth : the Arabidopsis jetlag

    NARCIS (Netherlands)

    Bours, R.M.E.H.

    2014-01-01

      Light and temperature are important determinants of plant growth and development. Plant elongation is stimulated by positively increasing differences between day and night temperature (+DIF, phased cycles). In contrast, a negative temperature difference (-DIF, antiphased cycles) reduces

  1. Plant extracts used as growth promoters in broilers

    Directory of Open Access Journals (Sweden)

    MSR Barreto

    2008-06-01

    Full Text Available Two experiments were carried out to assess the efficacy of plant extracts as alternatives for antimicrobial growth promoters in broiler diets. The performance experiment included 1,200 male broilers raised from 1 to 42 days of age. The metabolism experiment used 96 male broilers in the grower phase housed in metabolic cages for total excreta collection. At the end of the metabolism experiment, 24 birds were sacrificed to assess organ morphometrics. In both experiments, the following treatments were applied: control diet (CD; CD + 10 ppm avilamycin; CD + 1000 ppm oregano extract; CD + 1000 ppm clove extract; CD + 1000 ppm cinnamon extract; and CD + 1000 ppm red pepper extract. The microencapsulated extracts contained 20% of essential oil. No significant differences (P>0.05 in the studied performance parameters were observed among treatments. The dietary supplementation of the extracts did not influence (P>0.05 nitrogen-corrected apparent metabolizable energy values. In general, organ morphometrics was not affected by the experimental treatments, but birds fed the control diet had higher liver relative weight (P<0.05 as compared to those fed the diet containing red pepper extract, which presented the lowest liver relative weight. These results showed that there was no effect of the tested plant extracts on live performance or in organ morphometrics.

  2. Computational insight into the chemical space of plant growth regulators.

    Science.gov (United States)

    Bushkov, Nikolay A; Veselov, Mark S; Chuprov-Netochin, Roman N; Marusich, Elena I; Majouga, Alexander G; Volynchuk, Polina B; Shumilina, Daria V; Leonov, Sergey V; Ivanenkov, Yan A

    2016-02-01

    An enormous technological progress has resulted in an explosive growth in the amount of biological and chemical data that is typically multivariate and tangled in structure. Therefore, several computational approaches have mainly focused on dimensionality reduction and convenient representation of high-dimensional datasets to elucidate the relationships between the observed activity (or effect) and calculated parameters commonly expressed in terms of molecular descriptors. We have collected the experimental data available in patent and scientific publications as well as specific databases for various agrochemicals. The resulting dataset was then thoroughly analyzed using Kohonen-based self-organizing technique. The overall aim of the presented study is to investigate whether the developed in silico model can be applied to predict the agrochemical activity of small molecule compounds and, at the same time, to offer further insights into the distinctive features of different agrochemical categories. The preliminary external validation with several plant growth regulators demonstrated a relatively high prediction power (67%) of the constructed model. This study is, actually, the first example of a large-scale modeling in the field of agrochemistry.

  3. Bioprospecting glacial ice for plant growth promoting bacteria.

    Science.gov (United States)

    Balcazar, Wilvis; Rondón, Johnma; Rengifo, Marcos; Ball, María M; Melfo, Alejandra; Gómez, Wileidy; Yarzábal, Luis Andrés

    2015-08-01

    Glaciers harbor a wide diversity of microorganisms, metabolically versatile, highly tolerant to multiple environmental stresses and potentially useful for biotechnological purposes. Among these, we hypothesized the presence of bacteria able to exhibit well-known plant growth promoting traits (PGP). These kinds of bacteria have been employed for the development of commercial biofertilizers; unfortunately, these biotechnological products have proven ineffective in colder climates, like the ones prevailing in mountainous ecosystems. In the present work, we prospected glacial ice collected from two small tropical glaciers, located above 4.900 m in the Venezuelan Andes, for cold-active PGP bacteria. The initial screening strategy allowed us to detect the best inorganic-P solubilizers at low temperatures, from a sub-sample of 50 bacterial isolates. Solubilization of tricalcium phosphate, aluminum- and iron-phosphate, occurred in liquid cultures at low temperatures and was dependent on medium acidification by gluconic acid production, when bacteria were supplied with an appropriate source of carbon. Besides, the isolates were psychrophilic and in some cases exhibited a broad range of growth-temperatures, from 4 °C to 30 °C. Additional PGP abilities, including phytohormone- and HCN production, siderophore excretion and inhibition of phytopathogens, were confirmed in vitro. Nucleotidic sequence analysis of 16S rRNA genes allowed us to place the isolates within the Pseudomonas genus. Our results support the possible use of these strains to develop cold-active biofertilizers to be used in mountainous agriculture.

  4. 76 FR 17160 - Office of New Reactors; Final Interim Staff Guidance on the Review of Nuclear Power Plant Designs...

    Science.gov (United States)

    2011-03-28

    ... COMMISSION Office of New Reactors; Final Interim Staff Guidance on the Review of Nuclear Power Plant Designs... Guidance (ISG) DC/COL-ISG-021 titled ``Interim Staff Guidance on the Review of Nuclear Power Plant Designs... Nuclear Power Plants,'' March 2007, Standard Review Plan (SRP), Section 8.3.1 and Sections 9.5.4 through...

  5. Biological management of Sclerotinia sclerotiorum in pea using plant growth promoting microbial consortium.

    Science.gov (United States)

    Jain, Akansha; Singh, Akanksha; Singh, Surendra; Singh, Harikesh Bahadur

    2015-08-01

    The beneficial plant-microbe interactions play crucial roles in protection against large number of plant pathogens causing disease. The present study aims to investigate the growth promoting traits induced by beneficial microbes namely Pseudomonas aeruginosa PJHU15, Trichoderma harzianum TNHU27, and Bacillus subtilis BHHU100 treated singly and in combinations under greenhouse and field conditions to control Sclerotinia sclerotiorum. Plants treated with three microbe consortium enhanced plant growth maximally both in the presence and absence of the pathogen. Increase in plant length, total biomass, number of leaves, nodules and secondary roots, total chlorophyll and carotenoid content, and yield were recorded in plants treated with microbial consortia. Also, a decrease in plant mortality was observed in plants treated with microbial consortia in comparison to untreated control plants challenged with S. sclerotiorum. Furthermore, the decrease in disease of all the treatments can be associated with differential improvement of growth induced in pea.

  6. Differential growth stimulation response of potato towards inoculation with taxonomically diverse plant growth promoting rhizobacteria

    Directory of Open Access Journals (Sweden)

    Tahir eNaqqash

    2016-02-01

    Full Text Available Rhizosphere engineering with beneficial plant growth promoting bacteria offers great promise for sustainable crop yield. Potato is an important food commodity that needs large inputs of nitrogen and phosphorus fertilizers. To overcome high fertilizer demand (especially nitrogen, five bacteria, i.e. Azospirillum sp.TN10, Agrobacterium sp.TN14, Pseudomonas sp.TN36, Enterobactersp. TN38 and Rhizobium sp. TN42 were isolated from the potato rhizosphere on nitrogen-free malate medium and identified based on their 16S rRNA gene sequences. Three strains, i.e. TN10, TN38 and TN42, showed nitrogen fixation (92.67-134.54 nmol h-1mg-1protein, while all showed the production of indole acetic acid in the presence and/or absence of L-tryptophan. Azospirillum sp. TN10 produced the highest amount of IAA, as measured by spectrophotometry (312.14 µg mL-1 and HPLC (18.3 µg mL-1. Inoculation with these bacteria under axenic conditions resulted in differential growth responses of potato. Azospirillum sp. TN10 incited the highest increase in potato fresh and dry weight over control plants, along with increased N contents of shoot and roots. All strains were able to colonize and maintain their population densities in the potato rhizosphere for upto 60 days, with Azospirillum sp. and Rhizobium sp. showing the highest survival. Plant root colonization potential was analyzed by transmission electron microscopy of root sections inoculated with Azospirillum sp. TN10. Of the five test strains, Azospirillum sp. TN10 has the greatest potential to increase the growth and nitrogen uptake of potato. Hence, it is suggested as a good candidate for the production of potato biofertilizer for integrated nutrient management with potato.

  7. [Advances in studies on growth metabolism and response mechanisms of medicinal plants under drought stress].

    Science.gov (United States)

    Si, Can; Zhang, Jun-Yi; Xu, Hu-Chao

    2014-07-01

    Drought stress exerts a considerable effect on growth, physiology and secondary metabolisms of the medicinal plants. It could inhabit the growth of the medicinal plants but promote secretion of secondary metabolites. Other researches indicated that the medicinal plants could depend on the ABA signaling pathway and secreting osmotic substances to resist the drought stress and reduce the damage by it. The article concludes the changes in growth, physiology, secondary metabolisms and response mechanisms of medicinal plants to drought stress that provides a theoretical basis for exploring the relationship between medicinal plants and drought stress.

  8. Final focus shielding designs for modern heavy-ion fusion power plant designs

    Science.gov (United States)

    Latkowski, J. F.; Meier, W. R.

    2001-05-01

    Recent work in heavy-ion fusion accelerators and final focusing systems shows a trend towards less current per beam, and thus, a greater number of beams. Final focusing magnets are susceptible to nuclear heating, radiation damage, and neutron activation. The trend towards more beams, however, means that there can be less shielding for each magnet. Excessive levels of nuclear heating may lead to magnet quench or to an intolerable recirculating power for magnet cooling. High levels of radiation damage may result in short magnet lifetimes and low reliability. Finally, neutron activation of the magnet components may lead to difficulties in maintenance, recycling, and waste disposal. The present work expands upon previous, three-dimensional magnet shielding calculations for a modified version of the HYLIFE-II IFE power plant design. We present key magnet results as a function of the number of beams.

  9. Final Focus Shielding Designs for Modern Heavy-Ion Fusion Power Plant Designs

    Energy Technology Data Exchange (ETDEWEB)

    Latkowski, J F; Meier, W R

    2000-07-05

    Recent work in heavy-ion fusion accelerators and final focusing systems shows a trend towards less current per beam, and thus, a greater number of beams. Final focusing magnets are susceptible to nuclear heating, radiation damage, and neutron activation. The trend towards more beams, however, means that there can be less shielding for each magnet, Excessive levels of nuclear heating may lead to magnet quench or an intolerable recirculating power for magnet cooling. High levels of radiation damage may result in short magnet lifetimes and low reliability. Finally, neutron activation of the magnet components may lead to difficulties in maintenance, recycling, and waste disposal. The present work expands upon previous, three-dimensional magnet shielding calculations for a modified version of the HYLIFE-I1 IFE power plant design. We present key magnet results as a function of the number of beams.

  10. Peniamidienone and penidilamine, plant growth regulators produced by the fungus Penicillium sp. No. 13.

    Science.gov (United States)

    Kimura, Y; Mizuno, T; Kawano, T; Okada, K; Shimada, A

    2000-04-01

    Peniamidienone and penidilamine were isolated from cultures of the fungus Penicillium sp. No. 13 as new plant growth regulators and their structures were established by NMR spectroscopic studies. Peniamidienone showed weak inhibition of lettuce seedling growth.

  11. High-throughput growth prediction for Lactuca sativa L. seedlings using chlorophyll fluorescence in a plant factory with artificial lighting

    Directory of Open Access Journals (Sweden)

    Shogo eMoriyuki

    2016-03-01

    Full Text Available Poorly grown plants that result from differences in individuals lead to large profit losses for plant factories that use large electric power sources for cultivation. Thus, identifying and culling the low-grade seedlings at an early stage, using so-called seedling diagnosis technology, plays an important role in avoiding large losses in plant factories. In this study, we developed a high-throughput diagnosis system using the measurement of chlorophyll fluorescence (CF in a commercial large-scale plant factory, which produces about 5,000 lettuce plants every day. At an early stage (6 days after sowing, a CF image of 6,000 seedlings was captured every 4 hours on the final greening day by a high-sensitivity CCD camera and an automatic transferring machine, and biological indices were extracted. Using machine learning, plant growth can be predicted with a high degree of accuracy based on biological indices including leaf size, amount of CF, and circadian rhythms in CF. Growth prediction was improved by addition of temporal information on CF. The present data also provide new insights into the relationships between growth and temporal information regulated by the inherent biological clock.

  12. A native plant growth promoting bacterium, Bacillus sp. B55, rescues growth performance of an ethylene-insensitive plant genotype in nature.

    Science.gov (United States)

    Meldau, Dorothea G; Long, Hoang H; Baldwin, Ian T

    2012-01-01

    Many plants have intimate relationships with soil microbes, which improve the plant's growth and fitness through a variety of mechanisms. Bacillus sp. isolates are natural root-associated bacteria, isolated from Nicotiana attenuata plant roots growing in native soils. A particular isolate B55, was found to have dramatic plant growth promotion (PGP) effects on wild type (WT) and transgenic plants impaired in ethylene (ET) perception (35S-etr1), the genotype from which this bacterium was first isolated. B55 not only improves N. attenuata growth under in vitro, glasshouse, and field conditions, but it also "rescues" many of the deleterious phenotypes associated with ET insensitivity. Most notably, B55 dramatically increases the growth and survival of 35S-etr1 plants under field conditions. To our knowledge, this is the first demonstration of a PGP effect in a native plant-microbe association under natural conditions. Our study demonstrates that this facultative mutualistic plant-microbe interaction should be viewed as part of the plant's extended phenotype. Possible modalities of recruitment and mechanisms of PGP are discussed.

  13. Plant Growth Experiments in Zeoponic Substrates: Applications for Advanced Life Support Systems

    Science.gov (United States)

    Ming, Douglas W.; Gruener, J. E.; Henderson, K. E.; Steinberg, S. L.; Barta, D. J.; Galindo, C.; Henninger, D. L.

    2001-01-01

    A zeoponic plant-growth system is defined as the cultivation of plants in artificial soils, which have zeolites as a major component (Allen and Ming, 1995). Zeolites are crystalline, hydrated aluminosilicate minerals that have the ability to exchange constituent cations without major change of the mineral structure. Recently, zeoponic systems developed at the National Aeronautics and Space Administration (NASA) slowly release some (Allen et at., 1995) or all of the essential plant-growth nutrients (Ming et at., 1995). These systems have NH4- and K-exchanged clinoptilolite (a natural zeolite) and either natural or synthetic apatite (a calcium phosphate mineral). For the natural apatite system, Ca and P were made available to the plant by the dissolution of apatite. Potassium and NH4-N were made available by ion-exchange reactions involving Ca(2+) from apatite dissolution and K(+) and NH4(+) on zeolitic exchange sites. In addition to NH4-N, K, Ca, and P, the synthetic apatite system also supplied Mg, S, and other micronutrients during dissolution (Figure 1). The overall objective of this research task is to develop zeoponic substrates wherein all plant growth nutrients are supplied by the plant growth medium for several growth seasons with only the addition of water. The substrate is being developed for plant growth in Advanced Life Support (ALS) testbeds (i.e., BioPLEX) and microgravity plant growth experiments. Zeoponic substrates have been used for plant growth experiments on two Space Shuttle flight experiments (STS-60; STS-63; Morrow et aI., 1995). These substrates may be ideally suited for plant growth experiments on the International Space Station and applications in ALS testbeds. However, there are several issues that need to be resolved before zeoponics will be the choice substrate for plant growth experiments in space. The objective of this paper is to provide an overview on recent research directed toward the refinement of zeoponic plant growth substrates.

  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. Different Growth Promoting Effects of Endophytic Bacteria on Invasive and Native Clonal Plants

    Science.gov (United States)

    Dai, Zhi-Cong; Fu, Wei; Wan, Ling-Yun; Cai, Hong-Hong; Wang, Ning; Qi, Shan-Shan; Du, Dao-Lin

    2016-01-01

    The role of the interactions between endophytes and alien plants has been unclear yet in plant invasion. We used a completely germ-free culture system to quantify the plant growth-promoting (PGP) effects of endophytic bacteria Bacillus sp. on aseptic seedlings of Wedelia trilobata and of its native clonal congener W. chinensis. The endophytic bacteria did not affect the growth of W. chinensis, but they significantly promoted the growth of W. trilobata. With the PGP effects of endophytic bacteria, relative change ratios of the clonal traits and the ramets’ growth traits of W. trilobata were significantly greater than those of W. chinensis. Our results indicate that the growth-promoting effects of endophytes may differ between invasive and native clonal plants, and the endophytes of invasive plant may be host-specific to facilitate plant invasion. PMID:27252722

  16. Different Growth Promoting Effects of Endophytic Bacteria on Invasive and Native Clonal Plants.

    Science.gov (United States)

    Dai, Zhi-Cong; Fu, Wei; Wan, Ling-Yun; Cai, Hong-Hong; Wang, Ning; Qi, Shan-Shan; Du, Dao-Lin

    2016-01-01

    The role of the interactions between endophytes and alien plants has been unclear yet in plant invasion. We used a completely germ-free culture system to quantify the plant growth-promoting (PGP) effects of endophytic bacteria Bacillus sp. on aseptic seedlings of Wedelia trilobata and of its native clonal congener W. chinensis. The endophytic bacteria did not affect the growth of W. chinensis, but they significantly promoted the growth of W. trilobata. With the PGP effects of endophytic bacteria, relative change ratios of the clonal traits and the ramets' growth traits of W. trilobata were significantly greater than those of W. chinensis. Our results indicate that the growth-promoting effects of endophytes may differ between invasive and native clonal plants, and the endophytes of invasive plant may be host-specific to facilitate plant invasion.

  17. Different growth promoting effects of endophytic bacteria on invasive and native clonal plants

    Directory of Open Access Journals (Sweden)

    Zhi-Cong eDai

    2016-05-01

    Full Text Available The role of the interactions between endophytes and alien plants has been unclear yet in plant invasion. We used a completely germ-free culture system to quantify the plant growth-promoting (PGP effects of endophytic bacteria Bacillus sp. on aseptic seedlings of W. trilobata and of its native clonal congener W. chinensis. The endophytic bacteria did not affect the growth of W. chinensis, but they significantly promoted the growth of W. trilobata. With the PGP effects of endophytic bacteria, relative change ratios of the clonal traits and the ramets' growth traits of W. trilobata were significantly greater than those of W. chinensis. Our results indicate that the growth-promoting effects of endophytes may differ between invasive and native clonal plants, and the endophytes of invasive plant may be host-specific to facilitate plant invasion.

  18. Effect of plant growth regulators on indices of growth analysis for sweet passion fruit seedlings (Passiflora alata Curtis

    Directory of Open Access Journals (Sweden)

    Carmen Sílvia Fernandes Boaro

    2008-09-01

    Full Text Available The objective of this work was to investigate the effects of GA3 + IBA + cinetina on the growth of Passiflora alata Curtis plants through growth analysis. The experiment was carried out by completely randomized block design, with six treatments and four replications. The plant growth regulators, gibberellin (GA3, auxin (IBA and cytokinin (kinetin, were applied to leaves at concentrations of 0 (control, 25, 50, 75, 100, 125mL.L-1. The applications were performed at 48, 55, 52, 69, and 76 days after the emergence of the plants and the growths were evaluated five times at 7-day intervals. The first evaluations were accomplished 55 days after plant emergence. The leaf area ratio (RAF, specific leaf area (AFE, liquid assimilation rate (TCA, and relative growth rate (TCR were analyzed. The following data were also analyzed for P. alata Curtis plants: leaf area, leaf lamina dry mass and total leaves dry mass. The growth analysis, which employed the ANACRES computer program, indicated that the growth regulators increased plant productivity.

  19. Beneficial role of plant growth promoting bacteria and arbuscular mycorrhizal fungi on plant responses to heavy metal stress.

    Science.gov (United States)

    Gamalero, Elisa; Lingua, Guido; Berta, Graziella; Glick, Bernard R

    2009-05-01

    Heavy metal pollution is a major worldwide environmental concern that has recently motivated researchers to develop a variety of novel approaches towards its cleanup. As an alternative to traditional physical and chemical methods of environmental cleanup, scientists have developed phytoremediation approaches that include the use of plants to remove or render harmless a range of compounds. Both plant growth promoting bacteria (PGPB) and arbuscular mycorrhizal fungi (AMF) can be used to facilitate the process of phytoremediation and the growth of plants in metal-contaminated soils. This review focuses on the recent literature dealing with the effects of plant growth-promoting bacteria and AM fungi on the response of plants to heavy metal stress and points the way to strategies that may facilitate the practical realization of this technology.

  20. Effect of seaweed extracts on growth and yield of rice plants

    Directory of Open Access Journals (Sweden)

    ALUH NIKMATULLAH

    2010-07-01

    Full Text Available Sunarpi, Jupri A, Kurnianingsih R, Julisaniah NI, Nikmatullah A 2010. Effect of seaweed extracts on growth and yield of rice plants. Nusantara Bioscience 2: 73-77. Application of liquid seaweed fertilizers on some plant specieshas been reported to decrease application doses of nitrogen, phosphorus and potassium on some crop plants, as well as stimulating growth and production of many plants. It has been reported that there are at least 59 species of seaweeds found in coastal zone of West Nusa Tenggara Province, 15 of those species weres able to stimulate germination, growth and production of some horticultural and legume plants. The aim of this research is to investigate the effect of seaweed extracts obtained from ten species on growth and production of rice plants. To achive the goal, seaweed (100 g per species wasextracted with 100 mL of water, to obtain the concentration of 100%. Seaweed extract (15% was sprayed into the rice plants during vegetative and generative stages. Subsequently, the growth and yield parameters of rice plants were measured. The results shown that extracts of Sargassum sp.1, Sargassum sp.2, Sargassum polycistum, Hydroclathrus sp., Turbinaria ornata, and Turbinaria murayana, were able to induce growth of rice plants. However, only the Hydroclathrus sp. extract could enhance both growth and production of rice plants.

  1. Preparation for the Proof of Concept Flight of the Veggie Plant Growth Chamber

    Science.gov (United States)

    Massa, Gioia; Morrow, Robert; Hummerick, Mary; Newsham, Gerard; Wheeler, Raymond

    2012-01-01

    Veggie is a small plant growth chamber designed and built by ORBITEC that will fly to the International Space Station on SpaceX-3, scheduled for the summer of 2013. Ultimately Veggie will be used for research, education and outreach, and crew recreation. We want to demonstrate the functionality of this hardware by testing a scenario that could allow the crew to grow and consume fresh vegetables. Veggie will be collapsed and transported flat in a cargo transfer bag, and deployed on orbit, where it will be installed in an EXPRESS rack. The chamber consists of three subsystems: an LED light cap, a transparent bellows, and a root mat reservoir assembly. The bellows and flexible support arms allow the distance between plants and light cap to be adjusted for different ages and types of plants. Researchers at Kennedy Space Center and ORBITEC have been working to develop the plant growth interfaces for the proof of concept flight. We have developed a rooting pillow, consisting of a small bag containing media, time release fertilizer, seeds, and a wicking surface to conduct water from the root mat reservoir. Prototype pillows have been tested and results have influenced the design of flight pillows, which will be modified for microgravity from flight-approved materials. Several studies have been conducted selecting species and comparing media types in analog systems. Water content seems to be the most important factor differentiating media types in these small growth volumes (100 mL). Media type also influenced microbial levels on plants. Since produce sanitizing agents are not currently approved for growing food crops on orbit, plants and media types having very low microbial levels are being selected. Lettuce, mizuna, and other salad greens typically have microbial counts less than 10(exp 4) colony forming units and thus are good candidates for spaceflight. As we approach flight verification testing, we will finalize species, media selection, harvesting, and microbial

  2. Plant Growth Promotion by Volatile Organic Compounds Produced by Bacillus subtilis SYST2

    Science.gov (United States)

    Tahir, Hafiz A. S.; Gu, Qin; Wu, Huijun; Raza, Waseem; Hanif, Alwina; Wu, Liming; Colman, Massawe V.; Gao, Xuewen

    2017-01-01

    Bacterial volatiles play a significant role in promoting plant growth by regulating the synthesis or metabolism of phytohormones. In vitro and growth chamber experiments were conducted to investigate the effect of volatile organic compounds (VOCs) produced by the plant growth promoting rhizobacterium Bacillus subtilis strain SYST2 on hormone regulation and growth promotion in tomato plants. We observed a significant increase in plant biomass under both experimental conditions; we observed an increase in photosynthesis and in the endogenous contents of gibberellin, auxin, and cytokinin, while a decrease in ethylene levels was noted. VOCs emitted by SYST2 were identified through gas chromatography-mass spectrometry analysis. Of 11 VOCs tested in glass jars containing plants in test tubes, only two, albuterol and 1,3-propanediole, were found to promote plant growth. Furthermore, tomato plants showed differential expression of genes involved in auxin (SlIAA1. SlIAA3), gibberellin (GA20ox-1), cytokinin (SlCKX1), expansin (Exp2, Exp9. Exp 18), and ethylene (ACO1) biosynthesis or metabolism in roots and leaves in response to B. subtilis SYST2 VOCs. Our findings suggest that SYST2-derived VOCs promote plant growth by triggering growth hormone activity, and provide new insights into the mechanism of plant growth promotion by bacterial VOCs. PMID:28223976

  3. ESM Calculations for Hydroponic Plant and Fungi Growth Chambers, Biosolids Dewatering Plant System, and Tilapia Growth System--EAC Presentation 2004

    OpenAIRE

    Aydogan, Selen; Blau, Gary; Pekny, Joseph; Reklaitis, Gintaras

    2004-01-01

    In this work, preliminary Equivalent System Mass (ESM) estimations of the Hydroponic Plant and Fungi Growth Chambers, Biosolids Dewatering Plant and Tilapia Growth Systems are presented. ESM may be used to evaluate a system or technology based on its mass, volume, power, cooling and manpower requirements. This ESM analysis focuses on a hypothetical device, instead of the anticipated technology that is system flight proven in mission operations. We have examined the Evolved Mars Base mission, ...

  4. Cultivable endophytic bacteria from leaf bases of Agave tequilana and their role as plant growth promoters

    OpenAIRE

    Martínez-Rodríguez,Julia del C.; Marcela De la Mora-Amutio; Luis A. Plascencia-Correa; Esmeralda Audelo-Regalado; Guardado, Francisco R.; Elías Hernández-Sánchez; Peña-Ramírez, Yuri J.; Adelfo Escalante; Miguel J. Beltrán-García; Tetsuya Ogura

    2015-01-01

    Agave tequilana Weber var. 'Azul' is grown for the production of tequila, inulin and syrup. Diverse bacteria inhabit plant tissues and play a crucial role for plant health and growth. In this study culturable endophytic bacteria were extracted from leaf bases of 100 healthy Agave tequilana plants. In plant tissue bacteria occurred at mean population densities of 3 million CFU/g of fresh plant tissue. Three hundred endophytic strains were isolated and 16s rDNA sequences grouped the bacteria in...

  5. Plant growth-promoting rhizobacteria strain Bacillus amyloliquefaciens NJN-6-enriched bio-organic fertilizer suppressed Fusarium wilt and promoted the growth of banana plants.

    Science.gov (United States)

    Yuan, Jun; Ruan, Yunze; Wang, Beibei; Zhang, Jian; Waseem, Raza; Huang, Qiwei; Shen, Qirong

    2013-04-24

    Bacillus amyloliquefaciens strain NJN-6 is an important plant growth-promoting rhizobacteria (PGPR) which can produce secondary metabolites antagonistic to several soil-borne pathogens. In this study, the ability of a bio-organic fertilizer (BIO) containing NJN-6 strain to promote the growth and suppress Fusarium wilt of banana plants was evaluated in a pot experiment. The results showed that the application of BIO significantly decreased the incidence of Fusarium wilt and promoted the growth of banana plants compared to that for the organic fertilizer (OF). To determine the beneficial mechanism of the strain, the colonization of NJN-6 strain on banana roots was evaluated using scanning electron microscopy (SEM). The plant growth-promoting hormones indole-3-acetic acid (IAA) and gibberellin A3 (GA3), along with antifungal lipopeptides iturin A, were detected when the NJN-6 strain was incubated in both Landy medium with additional l-tryptophan and in root exudates of banana plants. In addition, some antifungal volatile organic compounds and iturin A were also detected in BIO. In summary, strain NJN-6 could colonize the roots of banana plants after the application of BIO and produced active compounds which were beneficial for the growth of banana plants.

  6. Plant growth promoting bacteria from cow dung based biodynamic preparations.

    Science.gov (United States)

    Radha, T K; Rao, D L N

    2014-12-01

    Indigenous formulations based on cow dung fermentation are commonly used in organic farming. Three biodynamic preparations viz., Panchagavya (PG), BD500 and 'Cow pat pit' (CPP) showed high counts of lactobacilli (10(9) ml(-1)) and yeasts (10(4) ml(-1)). Actinomycetes were present only in CPP (10(4) ml(-1)) and absent in the other two. Seven bacterial isolates from these ferments were identified by a polyphasic approach: Bacillus safensis (PG1), Bacillus cereus (PG2, PG4 PG5), Bacillus subtilis (BD2) Lysinibacillus xylanilyticus (BD3) and Bacillus licheniformis (CPP1). This is the first report of L. xylanilyticus and B. licheniformis in biodynamic preparations. Only three carbon sources-dextrose, sucrose and trehalose out of 21 tested were utilized by all the bacteria. None could utilize arabinose, dulcitol, galactose, inositol, inulin, melibiose, raffinose, rhamnose and sorbitol. All the strains produced indole acetic acid (1.8-3.7 μg ml(-1) culture filtrate) and ammonia. None could fix nitrogen; but all except B. safensis and B. licheniformis could solubilize phosphorous from insoluble tri-calcium phosphate. All the strains except L. xylaniliticus exhibited antagonism to the plant pathogen Rhizoctonia bataticola whereas none could inhibit Sclerotium rolfsi. In green house experiment in soil microcosms, bacterial inoculation significantly promoted growth of maize; plant dry weight increased by ~21 % due to inoculation with B. cereus (PG2). Results provide a basis for understanding the beneficial effects of biodynamic preparations and industrial deployment of the strains.

  7. ER stress-induced protein, VIGG, disturbs plant cation homeostasis, which is correlated with growth retardation and robustness to ER stress

    Energy Technology Data Exchange (ETDEWEB)

    Katoh, Hironori; Fujita, Keiko; Takuhara, Yuki [Laboratory of Fruit Genetic Engineering, The Institute of Enology and Viticulture, University of Yamanashi, Kofu, Yamanashi 400-0005 (Japan); Ogawa, Atsushi [Department of Biological Production, Akita Prefectural University, Shimosinjyou-nakano 241-438, Akita 010-0195 (Japan); Suzuki, Shunji, E-mail: suzukis@yamanashi.ac.jp [Laboratory of Fruit Genetic Engineering, The Institute of Enology and Viticulture, University of Yamanashi, Kofu, Yamanashi 400-0005 (Japan)

    2011-02-18

    Highlights: {yields} VIGG is an ER stress-induced protein in plant. {yields} We examine the characteristics of VIGG-overexpressing Arabidopsis plants. {yields} VIGG-overexpressing plants reveal growth retardation and robustness to ER stress. {yields} VIGG disturbs cation homeostasis in plant. -- Abstract: VIGG is a putative endoplasmic reticulum (ER) resident protein induced by virus infection and ER stress, and is correlated with fruit quality in grapevine. The present study was undertaken to determine the biological function of VIGG in grapevine. Experiments using fluorescent protein-VIGG fusion protein demonstrated that VIGG is localized in ER and the ER targeting sequence is in the N-terminus. The overexpression of VIGG in Arabidopsis plant led to growth retardation. The rosette leaves of VIGG-overexpressing plants were smaller than those of the control plants and rolled at 42 days after seeding. VIGG-overexpressing plants revealed robustness to ER stress as well as the low expression of ER stress marker proteins, such as the luminal binding proteins. These characteristics of VIGG-overexpressing plants were supported by a microarray experiment that demonstrated the disruption of genes related to ER stress response and flowering, as well as cation mobility, in the plants. Finally, cation homeostasis in the plants was disturbed by the overexpression of VIGG. Taken together, these results suggest that VIGG may disturb cation homeostasis in plant, which is correlated with the robustness to ER stress and growth retardation.

  8. Tracer methods for investigating biosynthetic pathways and the metabolism of bioactive substances in plants. [Herbicides; Plant growth regulators

    Energy Technology Data Exchange (ETDEWEB)

    Schuette, H.R. (Akademie der Wissenschaften der DDR, Halle/Saale. Inst. fuer Biochemie der Pflanzen)

    1984-03-01

    Proceeding from the general terms of investigating the courses of reactions in plants by means of tracer methods, problems and possibilities of the methods are discussed on the basis of examples referring in particular to double labelling techniques and to the determination of the distribution of radioactivity in the resulting products. Examples of herbicides and plant growth regulators are used for describing metabolism studies.

  9. Effects of plant growth-promoting bacteria isolated from copper tailings on plants in sterilized and non-sterilized tailings.

    Science.gov (United States)

    Liu, Weiqiu; Yang, Chao; Shi, Si; Shu, Wensheng

    2014-02-01

    Ten strains of Cu-tolerant bacteria with potential plant growth-promoting ability were isolated by selecting strains with the ability to use 1-aminocyclopropane-1-carboxylate as a sole nitrogen source (designated ACC-B) or fix nitrogen (designated FLN-B) originating from the rhizosphere of plants growing on copper tailings. All 10 strains proved to have intrinsic ability to produce indole acetic acid and siderophores, and most of them could mobilize insoluble phosphate. In addition, a greenhouse study showed that ACC-B, FLN-B and a mixture of both had similar, potent ability to stimulate growth of Pennisetum purpureum, Medicago sativa and Oenothera erythrosepala plants grown on sterilized tailings. For instance, above-ground biomass of P. purpureum was 278-357% greater after 60d growth on sterilized tailings in their presence. They could also significantly promote the growth of the plants grown on non-sterilized tailings, though the growth-promoting effects were much weaker. So, strategies for using of the plant growth-promoting bacteria in the practice of phytoremediation deserve further studies to get higher growth-promoting efficiency. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. How Does Your Garden Grow? Early Conceptualization of Seeds and Their Place in the Plant Growth Cycle.

    Science.gov (United States)

    Hickling, Anne K.; Gelman, Susan A.

    1995-01-01

    Examined young children's understanding of seed origins and growth preconditions and the stages of plant growth. Found that, by 4.5 years, children realized that natural causal mechanisms underlie plant growth and appreciated the relationship of seeds to plants. Results suggest that preschoolers hold theory-like understandings of plants similar to…

  11. Effects of Plant Growth Hormones on Mucor indicus Growth and Chitosan and Ethanol Production.

    Science.gov (United States)

    Safaei, Zahra; Karimi, Keikhosro; Golkar, Poorandokht; Zamani, Akram

    2015-07-22

    The objective of this study was to investigate the effects of indole-3-acetic acid (IAA) and kinetin (KIN) on Mucor indicus growth, cell wall composition, and ethanol production. A semi-synthetic medium, supplemented with 0-5 mg/L hormones, was used for the cultivations (at 32 °C for 48 h). By addition of 1 mg/L of each hormone, the biomass and ethanol yields were increased and decreased, respectively. At higher levels, however, an inverse trend was observed. The glucosamine fraction of the cell wall, as a representative for chitosan, followed similar but sharper changes, compared to the biomass. The highest level was 221% higher than that obtained without hormones. The sum of glucosamine and N-acetyl glucosamine (chitin and chitosan) was noticeably enhanced in the presence of the hormones. Increase of chitosan was accompanied by a decrease in the phosphate content, with the lowest phosphate (0.01 g/g cell wall) being obtained when the chitosan was at the maximum (0.45 g/g cell wall). In conclusion, IAA and KIN significantly enhanced the M. indicus growth and chitosan production, while at the same time decreasing the ethanol yield to some extent. This study shows that plant growth hormones have a high potential for the improvement of fungal chitosan production by M. indicus.

  12. Fusarium Oxysporum Volatiles Enhance Plant Growth Via Affecting Auxin Transport and Signaling.

    Science.gov (United States)

    Bitas, Vasileios; McCartney, Nathaniel; Li, Ningxiao; Demers, Jill; Kim, Jung-Eun; Kim, Hye-Seon; Brown, Kathleen M; Kang, Seogchan

    2015-01-01

    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.

  13. 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.

  14. Stomatal- and growth responses in willow to deficits in water- and nitrogen supply. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Stadenberg, I. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dep. for Production Ecology

    2002-02-01

    The two plants, grown with an [N] of 100 mg per litre and subjected to a decrease in N-supply decreased their leaf relative growth rate from 22% per day to 13% per day within 2 days. Stomatal conductance did not change significantly after the decrease in N-supply. Xylem samples did not show any significant changes in its composition of mineral nutrient elements after decreased N-supply. The three plants, grown with an [N] of 50 mg per litre and subjected to a decrease in N-supply, significantly decreased leaf relative growth rate from 18.5 % to 9 % per day within 2 days. Stomatal conductance did not change significantly after the decrease in N-supply. Xylem sap samples showed a significant decrease in [K] (74 mg/l to 42 mg/l) and [S] (11 mg/l to 3.2 mg/l) within 2 days after decreased N-supply. The four plants subjected to root drying decreased their leaf relative growth rate slightly but not significantly during the drying period. Xylem samples showed a significant decrease in S-concentration (11 mg/l to 1.3 mg/l) and [NO{sub 3}] (8.0 mg/l to 1.0 mg/l), while [Fe] increased significantly (0.065 mg/l to 0.14 mg/l). Stomatal conductance is known to decrease when plants are subjected to drying of part of the root system. This was shown for Salix dasyclados in a recent publication.

  15. 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...

  16. Draft Genome Sequence of Ochrobactrum intermedium Strain SA148, a Plant Growth-Promoting Desert Rhizobacterium

    KAUST Repository

    Lafi, Feras Fawzi

    2017-03-03

    Ochrobactrum intermedium strain SA148 is a plant growth-promoting bacterium isolated from sandy soil in the Jizan area of Saudi Arabia. Here, we report the 4.9-Mb draft genome sequence of this strain, highlighting different pathways characteristic of plant growth promotion activity and environmental adaptation of SA148.

  17. INTERSPECIFIC VARIATION IN THE GROWTH-RESPONSE OF PLANTS TO AN ELEVATED AMBIENT CO2 CONCENTRATION

    NARCIS (Netherlands)

    POORTER, H

    1993-01-01

    The effect of a doubling in the atmospheric CO2 concentration on the growth of vegetative whole plants was investigated. In a compilation of literature sources, the growth stimulation of 156 plant species was found to be on average 37%. This enhancement is small compared to what could be expected on

  18. Direct application of east coast geothermal resources in a frozen food plant. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Ammerlaan, A.C.F.; Knebel, M.E.; Czarnecki, R.J.

    1979-01-01

    The technical and economic viability of retrofitting an existing frozen food plant in Salisbury, Maryland to utilize the anticipated geothermal resources in that area was evaluated, via a budgetary level design and cost estimating analysis. Based on predicted reservoir data, a design concept was developed from production well through the plant to final brine disposal. A parametric analysis of capital and operating costs was performed which covered the range of geothermal design data developed. Relevant social, financial, environmental, legal, and regulatory institutional relationships were examined and ways to eliminate any barriers they presented against the proposed application were explored. Based on results from the other tasks, the existing DOE East Coast Geothermal Development Plan was evaluated and possible alterations were proposed. (MHR)

  19. Next Generation Nuclear Plant (NGNP) Prismatic HTGR Conceptual Design Project - Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Saurwein, John

    2011-07-15

    This report is the Final Technical Report for the Next Generation Nuclear Plant (NGNP) Prismatic HTGR Conceptual Design Project conducted by a team led by General Atomics under DOE Award DE-NE0000245. The primary overall objective of the project was to develop and document a conceptual design for the Steam Cycle Modular Helium Reactor (SC-MHR), which is the reactor concept proposed by General Atomics for the NGNP Demonstration Plant. The report summarizes the project activities over the entire funding period, compares the accomplishments with the goals and objectives of the project, and discusses the benefits of the work. The report provides complete listings of the products developed under the award and the key documents delivered to the DOE.

  20. Final Report: Signal Transduction in Plant Development: chemical and Biochemical Approaches to Receptor Identification, May 15, 1991 - May 14, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Lynn, David

    1997-05-14

    Work on the phenolic signals in Striga has provided evidence that the compounds are detected via a chemical reaction, quite distinct from our current models of hormone/growth factor detection by membrane localized binding proteins. Evidence ha been obtained that the recognition mechanism is a redox reaction most likely controlled by plasma membrane localized oxidoreductases. While the existence of these redox systems have been demonstrated in both plants and animals, only recently has convincing evidence connecting e- transport with plant development emerged. These discoveries have profound consequences for both the control of plant cell growth as well as strategies for general growth control.

  1. Survival of two introduced plant growth promoting micro-organisms in green roof soil in southern Finland

    OpenAIRE

    Xie, Long

    2014-01-01

    Glomus intraradices and Bacillus amyloliquefaciens are two commercially used plant growth promoting micro-organisms. They associate with plant roots to facilitate host plants to absorb nutrients, induce resistance against pathogens and pests, and regulate growth through phytohormones. Growth conditions for plants on green roofs are often unfavorable. In order to test whether growth and development of green roof plants could be enhanced via improving the microbial interface, G. intraradices an...

  2. Final Report: "Collaborative Project. Understanding the Chemical Processes That Affect Growth Rates of Freshly Nucleated Particles"

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James N. [NCAR, Boulder, CO (United States); McMurry, Peter H. [NCAR, Boulder, CO (United States)

    2015-11-12

    This final technical report describes our research activities that have, as the ultimate goal, the development of a model that explains growth rates of freshly nucleated particles. The research activities, which combine field observations with laboratory experiments, explore the relationship between concentrations of gas-phase species that contribute to growth and the rates at which those species are taken up. We also describe measurements of the chemical composition of freshly nucleated particles in a variety of locales, as well as properties (especially hygroscopicity) that influence their effects on climate. Our measurements include a self-organized, DOE-ARM funded project at the Southern Great Plains site, the New Particle Formation Study (NPFS), which took place during spring 2013. NPFS data are available to the research community on the ARM data archive, providing a unique suite observations of trace gas and aerosols that are associated with the formation and growth of atmospheric aerosol particles.

  3. 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...

  4. Modulation of plant growth and metabolism in cadmium-enriched environments.

    Science.gov (United States)

    Qadir, Shaista; Jamshieed, Sumiya; Rasool, Saiema; Ashraf, Muhammad; Akram, Nudrat Aisha; Ahmad, Parvaiz

    2014-01-01

    Cadmium (Cd) is a water soluble metal pollutant that is not essential to plant growth.It has attracted attention from soil scientists and plant nutritionists in recent years because of its toxicity and mobility in the soil-plant continuum. Even low levels of Cd (0.1-1 J.!M) cause adverse effects on plant growth and metabolism. Cadmium is known to trigger the synthesis of reactive oxygen species, hinder utilization, uptake and transport of essential nutrients and water, and modify photosynthetic machinery,thereby resulting in plant tissue death. Although the effects of Cd are dose- as well as plant species-dependent, some plants show Cd tolerance through a wide range of cellular responses. Such tolerance results from synthesis of osmolytes,generation of enzymatic and non-enzymatic antioxidants and metal-detoxifying peptides, changes in gene expression, and metal ion homeostasis and compartmentalization of ligand-metal complexes. Cd toxicity in plants produces effects on chlorophyllbio synthesis, reduces photosynthesis, and upsets plant water relations and hormonal and/or nutritional balances. All of these effects on plants and on plant metabolism ultimately reduce growth and productivity.In this review, we describe the extent to which Cd affects underlying metabolic processes in plants and how such altered processes affect plant growth. We review the sources of Cd contamination, its uptake, transportation and bioavailability and accumulation in plants, and its antagonistic and synergistic effects with other metals and compounds. We further address the effects of Cd on plant genetics and metabolism,and how plants respond to mitigate the adverse effects of Cd exposure, as well as strategies(e.g., plant breeding) that can reduce the impact of Cd contamination on plants.

  5. A native plant growth promoting bacterium, Bacillus megaterium B55, rescues growth performance of an ethylene insensitive plant genotype in nature

    Directory of Open Access Journals (Sweden)

    Dorothea Gertrud Meldau

    2012-06-01

    Full Text Available Many plants have intimate relationships with soil microbes that through a variety of mechanisms improve the plant’s growth and fitness. Bacillus megaterium is a natural endophyte isolated from Nicotiana attenuata plant roots growing in native soils. A particular isolate (B55, was found to have dramatic plant growth promoting (PGP effects on wild type (WT and transgenic plants impaired in ethylene (ET perception (35S-etr1, the genotype from which this bacteria was first isolated. B55 not only improves N. attenuata growth under in vitro, glasshouse and field conditions, but it also rescues many of the deleterious phenotypes associated with ET insensitivity. Most notably, B55 dramatically increases the growth and survival of 35S-etr1 plants under field conditions. To our knowledge, this is the first demonstration of a PGP effect in a native plant-microbe association under natural conditions. Our study demonstrates that this facultative mutualistic plant-microbe interaction should be viewed as part of the plant’s extended phenotype. Possible modalities of recruitment and mechanisms of PGP are discussed.

  6. Influence of Nitrogen Sources and Plant Growth-Promoting Rhizobacteria Inoculation on Growth, Crude Fiber and Nutrient Uptake in Squash (Cucurbita moschata Duchesne ex Poir. Plants

    Directory of Open Access Journals (Sweden)

    Alice I. TCHIAZE

    2016-06-01

    Full Text Available Plant growth promoting rhizobacteria (PGPR, B have immense potential application in sustainable agriculture as ecofriendly biofertilizers and biopesticides. In this study, the effects of three nitrogen (N sources (NO3-, NH4+ and NO3NH4 and PGPR on growth, crude fiber and nutrient uptake were investigated in squash plants. Some growth parameters [root dry weight (RDW, shoot dry weight (SDW, total plant dry weight (PDW, number of leaves (NL, shoot length (SL, stem diameter (SD and number of ramifications (NR], crude fiber (cellulose content and nutrient uptake (N, P, K, Ca, Mg, Na, Fe, Cu, Mn and Zn were determined. Application of NO3-,NH4+ or NO3NH4 singly or in combination with PGPR inoculation led to a significant increase in RDW, SDW, PDW, NL, SL, SD and NR. Na, Cu and Zn contents, on the contrary, decreased in inoculated treated plants while no significant differences were recorded in cellulose contents (CE of leaves except in plants fed with NO3-. The leaf CE content ranged from 12.58 to 13.67%. The plants supplied with NO3+B, NH4+B and NO3NH4+B showed significantly higher plant biomass and accumulation of N, P, K and Mn concentrations in leaves compared to all other treatments. These results suggest that specific combinations of PGPR with NO3-, NH4+ or NO3NH4 fertilizers can be considered as efficient alternative biofertilizers to improve significantly the squash growth and nutrient uptake.

  7. Plant defences limit herbivore population growth by changing predator-prey interactions.

    Science.gov (United States)

    Kersch-Becker, Mônica F; Kessler, André; Thaler, Jennifer S

    2017-09-13

    Plant quality and predators are important factors affecting herbivore population growth, but how they interact to regulate herbivore populations is not well understood. We manipulated jasmonate-induced plant resistance, exposure to the natural predator community and herbivore density to test how these factors jointly and independently affect herbivore population growth. On low-resistance plants, the predator community was diverse and abundant, promoting high predator consumption rates. On high-resistance plants, the predator community was less diverse and abundant, resulting in low predator consumption rate. Plant resistance only directly regulated aphid population growth on predator-excluded plants. When predators were present, plant resistance indirectly regulated herbivore population growth by changing the impact of predators on the herbivorous prey. A possible mechanism for the interaction between plant resistance and predation is that methyl salicylate, a herbivore-induced plant volatile attractive to predators, was more strongly induced in low-resistance plants. Increased plant resistance reduced predator attractant lures, preventing predators from locating their prey. Low-resistance plants may regulate herbivore populations via predators by providing reliable information on prey availability and increasing the effectiveness of predators. © 2017 The Author(s).

  8. Plant growth regulation in seed crops of perennial ryegrass (Lolium perenne L)

    DEFF Research Database (Denmark)

    Boelt, Birte; Lemaire, Charles; Abel, Simon;

    2016-01-01

    Seed yield components were recorded in plants of perennial ryegrass cv. Calibra a medium late, forage type (4n) in a two factorial block design with Nitrogen (N) and plant growth regulator (PGR) application in 2014 and 2015 at Aarhus University (AU), Flakkebjerg. For each plant, reproductive...

  9. Evaluation of Irrigation Methods for Highbush Blueberry. I. Growth and Water Requirements of Young Plants

    Science.gov (United States)

    A study was conducted in a new field of northern highbush blueberry (Vaccinium corymbosum L. 'Elliott') to determine the effects of different irrigation methods on growth and water requirements of uncropped plants during the first 2 years after planting. The plants were grown on mulched, raised beds...

  10. Dual Effect of the Cubic Ag₃PO₄ Crystal on Pseudomonas syringae Growth and Plant Immunity

    Directory of Open Access Journals (Sweden)

    Mi Kyung Kim

    2016-04-01

    Full Text Available We previously found that the antibacterial activity of silver phosphate crystals on Escherichia coli depends on their structure. We here show that the cubic form of silver phosphate crystal (SPC can also be applied to inhibit the growth of a plant-pathogenic Pseudomonas syringae bacterium. SPC pretreatment resulted in reduced in planta multiplication of P. syringae. Induced expression of a plant defense marker gene PR1 by SPC alone is suggestive of its additional plant immunity-stimulating activity. Since SPC can simultaneously inhibit P. syringae growth and induce plant defense responses, it might be used as a more effective plant disease-controlling agent.

  11. The influence of Plant Growth Promoting Rhizobacteria (PGPR on the reduction of abiotic stresses in crops

    Directory of Open Access Journals (Sweden)

    Omid Alizadeh

    2011-12-01

    Full Text Available Plants are always subjected to biotic and abiotic stresses in the environment which haveinfluences on the growth and development of the plants. Beneficial free-living soil bacteria are usuallyreferred as Plant-Growth Promoting Rhizobacteria or PGPR. Different plant growth-promotingRhizosphere bacteria, including associative bacteria such as: Azospirillum, Bacillus, Pseudomonas andEnterobacter group have been used for their beneficial influences on plants. Typically, PGPRs areassociated with plants root and augment plant productivity and immunity; however, recent worksshowed that PGPRs not have just induced the systemic tolerance to abiotic stress such as salt anddrought, but also they have increased the nutrient uptake from soils, and as a result the hazardousaccumulation of nitrates and phosphates in the agricultural soils can be reduced by usage of them.

  12. Draft Genome Sequence of Plant Growth-Promoting Rhizobacterium Pantoea sp. Strain AS-PWVM4

    OpenAIRE

    Khatri, Indu; Kaur, Sukhvir; Devi, Usha; Kumar, Navinder; Sharma,Deepak; Subramanian, Srikrishna; Saini, Adesh K.

    2013-01-01

    Nonpathogenic Pantoea spp. have been shown to confer biofertilizer and biocontrol activities, indicating their potential for increasing crop yield. Herein, we provide the high-quality genome sequence of Pantoea sp. strain AS-PWVM4, a Gram-negative motile plant growth-promoting rhizobacterium isolated from a pomegranate plant. The 4.9-Mb genome contains genes related to plant growth promotion and the synthesis of siderophores.

  13. Draft Genome Sequence of Plant Growth-Promoting Rhizobacterium Pantoea sp. Strain AS-PWVM4.

    Science.gov (United States)

    Khatri, Indu; Kaur, Sukhvir; Devi, Usha; Kumar, Navinder; Sharma, Deepak; Subramanian, Srikrishna; Saini, Adesh K

    2013-12-05

    Nonpathogenic Pantoea spp. have been shown to confer biofertilizer and biocontrol activities, indicating their potential for increasing crop yield. Herein, we provide the high-quality genome sequence of Pantoea sp. strain AS-PWVM4, a Gram-negative motile plant growth-promoting rhizobacterium isolated from a pomegranate plant. The 4.9-Mb genome contains genes related to plant growth promotion and the synthesis of siderophores.

  14. Role of plant growth regulators as chemical signals in plant-microbe interactions: a double edged sword.

    Science.gov (United States)

    Spence, Carla; Bais, Harsh

    2015-10-01

    Growth regulators act not only as chemicals that modulate plant growth but they also act as signal molecules under various biotic and abiotic stresses. Of all growth regulators, abscisic acid (ABA) is long known for its role in modulating plants response against both biotic and abiotic stress. Although the genetic information for ABA biosynthesis in plants is well documented, the knowledge about ABA biosynthesis in other organisms is still in its infancy. It is known that various microbes including bacteria produce and secrete ABA, but the overall functional significance of why ABA is synthesized by microbes is not known. Here we discuss the functional involvement of ABA biosynthesis by a pathogenic fungus. Furthermore, we propose that ABA biosynthesis in plant pathogenic fungi could be targeted for novel fungicidal discovery.

  15. The relationship between growth and soluble sugar concentration of Aloe vera plants grown under three levels of irradiance

    Energy Technology Data Exchange (ETDEWEB)

    Paez, A.; Gebre, G.M.; Tschaplinski, T.J. (Universidad del Zulia (Venezuela))

    1994-06-01

    The CAM plant Aloe vera was vegetatively propagated and grown under three irradiances: full sun, partial and deep shade (30% and 10% of ambient light, respectively) to determine the effect on growth, biomass allocation, and sugar concentration. After one year, the plants were harvested to determine final dry weight and the sugar concentration of the leaf mucilaginous gel. Plants grown under full sun produced twice the total dry weight of those grown under partial shade, with the difference equally partitioned between the shoot and root. Plants grown under full sun also produced thicker leaves, and more numerous and large auxiliary shoots. The dry weight of plants grown under deep shade was 8.6% that of plants grown under full sun, which was directly proportional to the irradiance received. Partial shade increased the number and length of leaves produced on the primary shoot, but the allocation of carbon to roots was the lowest of all treatments. Partial shade reduced the total sugar concentration of the leaf gel matrix to 34% that of plants under full sun, due to reductions in all sugars measured. Glucose was the most abundant soluble sugar, with its relative contribution to the total pool increasing under shade. In summary, the proportional effects of partial shading were greater on soluble sugar concentrations than on the total plant biomass produced.

  16. The plant growth-promoting effect of the nitrogen-fixing endophyte Pseudomonas stutzeri A15.

    Science.gov (United States)

    Pham, Van T K; Rediers, Hans; Ghequire, Maarten G K; Nguyen, Hiep H; De Mot, René; Vanderleyden, Jos; Spaepen, Stijn

    2017-04-01

    The use of plant growth-promoting rhizobacteria as a sustainable alternative for chemical nitrogen fertilizers has been explored for many economically important crops. For one such strain isolated from rice rhizosphere and endosphere, nitrogen-fixing Pseudomonas stutzeri A15, unequivocal evidence of the plant growth-promoting effect and the potential contribution of biological nitrogen fixation (BNF) is still lacking. In this study, we investigated the effect of P. stutzeri A15 inoculation on the growth of rice seedlings in greenhouse conditions. P. stutzeri A15 induced significant growth promotion compared to uninoculated rice seedlings. Furthermore, inoculation with strain A15 performed significantly better than chemical nitrogen fertilization, clearly pointing to the potential of this bacterium as biofertilizer. To assess the contribution of BNF to the plant growth-promoting effect, rice seedlings were also inoculated with a nitrogen fixation-deficient mutant. Our results suggest that BNF (at best) only partially contributes to the stimulation of plant growth.

  17. Effect of Plant Growth-Promoting Rhizobacteria on Growth,Nodulation and Nutrient Accumulation of Lentil Under Controlled Conditions

    Institute of Scientific and Technical Information of China (English)

    M.ZAFAR; M.K.ABBASI; M.A.KHAN; A.KHALIQ; T.SULTAN; M.ASLAM

    2012-01-01

    Application of plant growth-promoting rhizobacteria (PGPR) has been shown to increase legume growth and development under field and controlled environmental conditions.The present study was conducted to isolate plant growth-promoting rhizobacteria (PGPR) from the root nodules of lentil (Lens culinaris Medik.) grown in arid/semi-arid region of Punjab,Pakistan and examined their plant growth-promoting abilities.Five bacterial isolates were isolated,screened in vitro for plant growth-promoting (PGP)characteristics and their effects on the growth of lentil were assessed under in vitro,hydroponic and greenhouse (pot experiment)conditions.All the isolates were Gram negative,rod-shaped and circular in form and exhibited the plant growth-promoting attributes of phosphate solubilization and auxin (indole acetic acid,IAA) production.The IAA production capacity ranged in 0.5-11.0 μgmL-1and P solubilization ranged in 3 16 mg L-1.When tested for their effects on plant growth,the isolated strains had a stimulatory effect on growth,nodulation and nitrogen (N) and phosphorus (P) uptake in plants on nutrient-deficient soil.In the greenhouse pot experiment,application of PGPR significantly increased shoot length,fresh weight and dry weight by 65%,43% and 63% and the increases in root length,fresh weight and dry weight were 74%,54% and 92%,respectively,as compared with the uninoculated control.The relative increases in growth characteristics under in vitro and hydroponic conditions were even higher.PGPR also increased the number of pods per plant,1000-grain weight,dry matter yield and grain yield by 50%,13%,28% and 29%,respectively,over the control.The number of nodules and nodule dry mass increased by 170% and 136%,respectively.After inoculation with effective bacterial strains,the shoot,root and seed N and P contents increased,thereby increasing both N and P uptake in plants. The root elongation showed a positive correlation (R2 =0.67) with the IAA

  18. Development of a Configurable Growth Chamber with a Computer Vision System to Study Circadian Rhythm in Plants

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    Marcos Egea-Cortines

    2012-11-01

    Full Text Available Plant development is the result of an endogenous morphogenetic program that integrates environmental signals. The so-called circadian clock is a set of genes that integrates environmental inputs into an internal pacing system that gates growth and other outputs. Study of circadian growth responses requires high sampling rates to detect changes in growth and avoid aliasing. We have developed a flexible configurable growth chamber comprising a computer vision system that allows sampling rates ranging between one image per 30 s to hours/days. The vision system has a controlled illumination system, which allows the user to set up different configurations. The illumination system used emits a combination of wavelengths ensuring the optimal growth of species under analysis. In order to obtain high contrast of captured images, the capture system is composed of two CCD cameras, for day and night periods. Depending on the sample type, a flexible image processing software calculates different parameters based on geometric calculations. As a proof of concept we tested the system in three different plant tissues, growth of petunia- and snapdragon (Antirrhinum majus flowers and of cladodes from the cactus Opuntia ficus-indica. We found that petunia flowers grow at a steady pace and display a strong growth increase in the early morning, whereas Opuntia cladode growth turned out not to follow a circadian growth pattern under the growth conditions imposed. Furthermore we were able to identify a decoupling of increase in area and length indicating that two independent growth processes are responsible for the final size and shape of the cladode.

  19. Development of a configurable growth chamber with a computer vision system to study circadian rhythm in plants.

    Science.gov (United States)

    Navarro, Pedro J; Fernández, Carlos; Weiss, Julia; Egea-Cortines, Marcos

    2012-11-09

    Plant development is the result of an endogenous morphogenetic program that integrates environmental signals. The so-called circadian clock is a set of genes that integrates environmental inputs into an internal pacing system that gates growth and other outputs. Study of circadian growth responses requires high sampling rates to detect changes in growth and avoid aliasing. We have developed a flexible configurable growth chamber comprising a computer vision system that allows sampling rates ranging between one image per 30 s to hours/days. The vision system has a controlled illumination system, which allows the user to set up different configurations. The illumination system used emits a combination of wavelengths ensuring the optimal growth of species under analysis. In order to obtain high contrast of captured images, the capture system is composed of two CCD cameras, for day and night periods. Depending on the sample type, a flexible image processing software calculates different parameters based on geometric calculations. As a proof of concept we tested the system in three different plant tissues, growth of petunia- and snapdragon (Antirrhinum majus) flowers and of cladodes from the cactus Opuntia ficus-indica. We found that petunia flowers grow at a steady pace and display a strong growth increase in the early morning, whereas Opuntia cladode growth turned out not to follow a circadian growth pattern under the growth conditions imposed. Furthermore we were able to identify a decoupling of increase in area and length indicating that two independent growth processes are responsible for the final size and shape of the cladode.

  20. Improved electrical efficiency and bottom ash quality on waste combustion plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Peter A.; Nesterov, I.; Boejer, M.; Hyks, J.; Astrup, T.; Kloeft, H.; Dam-Johansen, K.; Lundtorp, K.; Hedegaard Madsen, O.; Frandsen, F. (Technical Univ. of Denmark, Kgs. Lyngby (Denmark)); Mogensen, Erhardt (Babcock and Wilcox Voelund A/S, Glostrup (Denmark))

    2010-07-01

    Investigations making it possible to evaluate and further develop concepts to improve electrical efficiency in a waste combustion plant were performed. Furthermore, one objective of the study was to investigate the possibilities of improving waste bottom ash leaching properties by use of a rotary kiln treatment. The project work included construction of a bench-scale rotary kiln, performing ash rotary kiln treatment experiments, conducting gas suction probe measurements on a waste incineration plant and making some concept evaluations. The influence of the rotary kiln thermal treatment on the leaching of Ca, Al, Si, Mg, Ba, Sr, Cl, Cu, Pb, Zn, Cr, Mo, sulfate, DOC and carbonate was determined. As a result of these tests, the rotary kiln thermal treatment of bottom ashes can be recommended for reducing the leaching of Cu, Pb, Cl, Zn and DOC; however, an increased leaching of Cr and Mo should be expected. The combustion conditions above the grate of a waste incineration plant were investigated and the release and concentration of volatile ash species in the flue gas such as Cl, Na, K, Ca, Pb, Zn and S were measured. The conducted measurements show that flue gas from grate sections 3 and 4 can produce a sufficiently hot flue gas that contains only low concentrations of corrosive species, and therefore can be used to increase superheater temperatures. Implementation of the so-called flue gas split concept together with other steam circle modifications on a waste combustion plant, and using a reasonable increase in final steam temperature from 400 to 500 deg. C, have the potential to increase electrical efficiency from 24 to 30% (with respect to lower fuel heating value) in a waste combustion plant. (Author)

  1. Beneficial effect of the rhizosphere microbial community for plant growth and health

    Directory of Open Access Journals (Sweden)

    Nihorimbere, V.

    2011-01-01

    Full Text Available Plant rhizosphere is the soil nearest to the plant root system where roots release large quantity of metabolites from living root hairs or fibrous root systems. These metabolites act as chemical signals for motile bacteria to move to the root surface but also represent the main nutrient sources available to support growth and persistence in the rhizosphere. Some of the microbes that inhabit this area are bacteria that are able to colonize very efficiently the roots or the rhizosphere soil of crop plants. These bacteria are referred to as plant growth promoting rhizobacteria (PGPR. They fulfil important functions for plant growth and health by various manners. Direct plant growth promotion may result either from improved nutrient acquisition and/or from hormonal stimulation. Diverse mechanisms are involved in the suppression of plant pathogens, which is often indirectly connected with plant growth. This paper describes the different mechanisms commonly used by most PGPR in their natural habitats to influence plant-growth and health.

  2. Carrageenans from red seaweeds as promoters of growth and elicitors of defense response in plants

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    Pushp Sheel Shukla

    2016-05-01

    Full Text Available Plants incessantly encounter abiotic and biotic stresses that limit their growth and productivity. However, conversely, plant growth can also be induced by treatments with various abiotic and biotic elicitors. Carrageenans are sulfated linear polysaccharides that represent major cellular constituents of seaweeds belonging to red algae (Rhodophyta. Recent research has unraveled the biological activity of carrageenans and of their oligomeric forms, the oligo carrageenans (OCs, as promoters of plant growth and as elicitors of defense responses against pests and diseases. In this review, we discuss the molecular mechanisms by which carrageenans and OCs mediate plant growth and plant defense responses. Carrageenans and OCs improve plant growth by regulating various metabolic processes such as photosynthesis and ancillary pathways, cell division, purine and pyrimidine synthetic pathways as well as metabolic pathways involved in nitrogen and sulfur assimilation. Carrageenans and OCs also induce plant defense responses against viroids, viruses, bacteria, fungi and insects by modulating the activity of different defense pathways, including salicylate, jasmonate and ethylene signaling pathways. Further studies will likely substantiate the beneficial effects of carrageenans and of OCs on plant growth and plant defense responses and open new avenues for their use in agriculture and horticultural industry.

  3. 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.

  4. 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; Mendoza-Mendoza, Artemio

    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.

  5. Morphological Transformation of Plant Cells in vitro and Its Effect on Plant Growth

    Institute of Scientific and Technical Information of China (English)

    GUO Zhigang; ZENG Zhaolin; LIU Ruizhi; DENG Ying

    2005-01-01

    Enhancement of cell growth in suspension cultures is urgently needed in plant cell culture engineering. This study investigates the relationship between morphological transformation and cell growth in callus and suspension cultures of saffron cells belonging to the cell line C96 induced from Crocus sativus L. In the suspension culture, an unbalanced osmotic pressure between the intracell and extracell regions induced a large morphological transformation which affected normal division of the saffron cells. An increase in osmotic pressure caused by the addition of sucrose inhibits the vacuolation and shrinkage of cytoplasm in the cells. As the sucrose concentration increases, the total amount of accumulated biomass also increases. Besides the sucrose concentration, increased ionic strength and inoculation ratio also help restrain to a large extent the vacuolation and shrinkage of the cytoplasm in the suspended cells, which results in increased biomass. The conditions for optimal biomass are: Murashige and Skoog's (MS) medium with 40 g/L sucrose and 60% (v/v) inoculation ratio.

  6. Effects of Ambient Humidity on Plant Growth Enhancement by Atmospheric Air Plasma Irradiation to Plant Seeds

    Science.gov (United States)

    Sarinont, Thapanut; Amano, Takaaki; Koga, Kazunori; Shiratani, Masaharu

    2015-09-01

    Humidity is an important factor for plasma-bio applications because composition of species generated by atmospheric pressure plasmas significantly depends on the humidity. Here we have examined effects of humidity on the growth enhancement to study the mechanism. Experiments were carried out with a scalable DBD device. 10 seeds of Raphanus sativus L. were set for x = 5 mm and y = 3 mm below the electrodes. The humidity Hair was 10 - 90 %Rh. The ratio of length of plants with plasma irradiation to that of control increases from 1.2 for Hair = 10 %Rh to 2.5 for Hair = 50 %Rh. The ratio is 2.5 for Hair = 50-90 %Rh. This humidity dependence is similar to the humidity dependence of O2+-H2O,H3O*, NO2--H2Oand NO3--H2Odensities, whereas it is different from that of other species such as O3, NO, and so on. The similarity gives information on key species for the growth enhancement.

  7. Properties of bacterial endophytes and their proposed role in plant growth.

    Science.gov (United States)

    Hardoim, Pablo R; van Overbeek, Leo S; Elsas, Jan Dirk van

    2008-10-01

    Bacterial endophytes live inside plants for at least part of their life cycle. Studies of the interaction of endophytes with their host plants and their function within their hosts are important to address the ecological relevance of endophytes. The modulation of ethylene levels in plants by bacterially produced 1-aminocyclopropane-1-carboxylate deaminase is a key trait that enables interference with the physiology of the host plant. Endophytes with this capacity might profit from association with the plant, because colonization is enhanced. In turn, host plants benefit by stress reduction and increased root growth. This mechanism leads to the concept of 'competent' endophytes, defined as endophytes that are equipped with genes important for maintenance of plant-endophyte associations. The ecological role of these endophytes and their relevance for plant growth are discussed here.

  8. Genetic and phenotypic diversity of plant growth promoting rhizobacteria isolated from sugarcane plants growing in pakistan.

    Science.gov (United States)

    Mehnaz, Samina; Baig, Deeba Noreen; Lazarovits, George

    2010-12-01

    Bacteria were isolated from roots of sugarcane varieties grown in the fields of Punjab. They were identified by using API20E/NE bacterial identification kits and from sequences of 16S rRNA and amplicons of the cpn60 gene. The majority of bacteria were found to belong to the genera of Enterobacter, Pseudomonas, and Klebsiella, but members of genera Azospirillum, Rhizobium, Rahnella, Delftia, Caulobacter, Pannonibacter, Xanthomonas, and Stenotrophomonas were also found. The community, however, was dominated by members of the Pseudomonadaceae and Enterobacteriaceae, as representatives of these genera were found in samples from every variety and location examined. All isolates were tested for the presence of five enzymes and seven factors known to be associated with plant growth promotion. Ten isolates showed lipase activity and eight were positive for protease activity. Cellulase, chitinase, and pectinase were not detected in any strain. Nine strains showed nitrogen fixing ability (acetylene reduction assay) and 26 were capable of solubilizing phosphate. In the presence of 100 mg/l tryptophan, all strains except one produced indole acetic acid in the growth medium. All isolates were positive for ACC deaminase activity. Six strains produced homoserine lactones and three produced HCN and hexamate type siderophores. One isolate was capable of inhibiting the growth of 24 pathogenic fungal strains of Colletotrichum, Fusarium, Pythium, and Rhizoctonia spp. In tests of their abilities to grow under a range of temperature, pH, and NaCl concentrations, all isolates grew well on plates with 3% NaCl and most of them grew well at 4 to 41degrees C and at pH 11.

  9. 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.

  10. Evaluation of pyritic mine tailings as a plant growth substrate.

    Science.gov (United States)

    Roseby, Stuart J; Kopittke, Peter M; Mulligan, David R; Menzies, Neal W

    2017-10-01

    At the Kidston gold mine, Australia, the direct establishment of vegetation on tailings was considered as an alternative to the use of a waste rock cover. The tailings acid/base account was used to predict plant growth limitation by acidity, and thus methods capable of identifying tailings that would acidify to pH 4.5 or lower were sought. Total S was found to be poorly correlated with acid-generating sulfide, and total C was poorly correlated with acid-neutralizing carbonate, precluding the use of readily determined total S and C as predictors of net acid generation. Therefore, the selected approach used assessment of sulfide content as a predictor of acid generation, and carbonate content as a measure of the acid-neutralizing capacity available at pH 5 and above. Using this approach, the majority of tailings (67%) were found to be non-acid generating. However, areas of potentially acid-generating tailings were randomly distributed across the dam, and could only be located by intensive sampling. The limitations imposed by the large sample numbers, and costly analysis of sulfide and carbonate, make it impractical to identify and ameliorate acid-generating areas prior to vegetation establishment. However, as only a small proportion of the tailings will acidify, a strategy of re-treating acid areas following oxidation is suggested. The findings of the present study will assist in the selection of appropriate methods for the prediction of net acid generation, particularly where more conservative measurements are required to allow vegetation to be established directly in tailings. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Linear growth and final height characteristics in adolescent females with anorexia nervosa.

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    Dalit Modan-Moses

    Full Text Available OBJECTIVE: Growth retardation is an established complication of anorexia nervosa (AN. However, findings concerning final height of AN patients are inconsistent. The aim of this study was to assess these phenomena in female adolescent inpatients with AN. METHODS: We retrospectively studied all 211 female adolescent AN patients hospitalized in an inpatient eating disorders department from 1/1/1987 to 31/12/99. Height and weight were assessed at admission and thereafter routinely during hospitalization and follow-up. Final height was measured in 69 patients 2-10 years after discharge. Pre-morbid height data was available in 29 patients. RESULTS: Patients' height standard deviation scores (SDS on admission (-0.285±1.0 and discharge (-0.271±1.02 were significantly (p<0.001 lower than expected in normal adolescents. Patients admitted at age ≤13 years, or less than 1 year after menarche, were more severely growth-impaired than patients admitted at an older age, (p = 0.03. Final height SDS, available for 69 patients, was -0.258±1.04, significantly lower than expected in a normal population (p = 0.04, and was more severely compromised in patients who were admitted less than 1 year from their menarche. In a subgroup of 29 patients with complete growth data (pre-morbid, admission, discharge, and final adult height, the pre-morbid height SDS was not significantly different from the expected (-0.11±1.1, whereas heights at the other time points were significantly (p = 0.001 lower (-0.56±1.2, -0.52±1.2, and -0.6±1.2, respectively. CONCLUSIONS: Our findings suggest that whereas the premorbid height of female adolescent AN patients is normal, linear growth retardation is a prominent feature of their illness. Weight restoration is associated with catch-up growth, but complete catch-up is often not achieved.

  12. Linear Growth and Final Height Characteristics in Adolescent Females with Anorexia Nervosa

    Science.gov (United States)

    Kochavi, Brigitte; Toledano, Anat; Segev, Sharon; Balawi, Fadel; Mitrany, Edith; Stein, Daniel

    2012-01-01

    Objective Growth retardation is an established complication of anorexia nervosa (AN). However, findings concerning final height of AN patients are inconsistent. The aim of this study was to assess these phenomena in female adolescent inpatients with AN. Methods We retrospectively studied all 211 female adolescent AN patients hospitalized in an inpatient eating disorders department from 1/1/1987 to 31/12/99. Height and weight were assessed at admission and thereafter routinely during hospitalization and follow-up. Final height was measured in 69 patients 2–10 years after discharge. Pre-morbid height data was available in 29 patients. Results Patients’ height standard deviation scores (SDS) on admission (−0.285±1.0) and discharge (−0.271±1.02) were significantly (p<0.001) lower than expected in normal adolescents. Patients admitted at age ≤13 years, or less than 1 year after menarche, were more severely growth-impaired than patients admitted at an older age, (p = 0.03). Final height SDS, available for 69 patients, was −0.258±1.04, significantly lower than expected in a normal population (p = 0.04), and was more severely compromised in patients who were admitted less than 1 year from their menarche. In a subgroup of 29 patients with complete growth data (pre-morbid, admission, discharge, and final adult height), the pre-morbid height SDS was not significantly different from the expected (−0.11±1.1), whereas heights at the other time points were significantly (p = 0.001) lower (−0.56±1.2, −0.52±1.2, and −0.6±1.2, respectively). Conclusions Our findings suggest that whereas the premorbid height of female adolescent AN patients is normal, linear growth retardation is a prominent feature of their illness. Weight restoration is associated with catch-up growth, but complete catch-up is often not achieved. PMID:23029058

  13. 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...

  14. Differential growth response to arbuscular mycorrhizal fungi and plant density in two wild plants belonging to contrasting functional types.

    Science.gov (United States)

    Pérez, Marisela; Urcelay, Carlos

    2009-10-01

    The effect of arbuscular mycorrhizal fungi (AMF) on plant growth was examined in two wild plant species belonging to contrasting functional types: an annual forb (Bidens pilosa, Asteraceae) and a deciduous shrub (Acacia caven, Fabaceae) at three contrasting plant densities (one, two, and three individuals per pot). AMF had a slightly negative effect on B. pilosa when the species grew in isolation while they positively affected A. caven. Positive effects of AMF on shoot mass of A. caven decreased at higher plant densities, while shoot mass of individuals of B. pilosa showed less marked differences between plant densities. When considering total biomass per pot, AMF positively affected A. caven growth while negatively affecting B. pilosa, at all three plant densities. Root/shoot ratio per pot was negatively affected by AMF but not plant density in both species. These findings highlight the importance of including plants belonging to different life forms and/or traits in research regarding the interaction between AMF and intraspecific plant competition.

  15. Effects of Eichhornia crassipes Growth on Aquatic Plants in Dianchi Lake

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The aim was to study the effects of Eichhornia crassipes as an invasive plant on aquatic plants in Dianchi Lake. [Method] Based on the determination of chlorophyll content of phytoplankton and submerged plant (Potamogeton pectinatus) in Dianchi Lake in different months, the effects of E. crassipes on aquatic plants in Dianchi Lake were studied, and the allelopathy effect of root culture solution of E. crassipes on Microcystis aquaticum was discussed. [Result] The growth of E. crassipes in Dianch...

  16. Crop management in greenhouses: adapting the growth conditions to the plant needs or adapting the plant to the growth conditions?

    NARCIS (Netherlands)

    Marcelis, L.F.M.; Pascale, De S.

    2009-01-01

    Strategies for improving greenhouse crop production should target both developing advanced technological systems and designing improved plants. Based on greenhouse experiments, crop models and biotechnological tools, this paper will discuss the physiology of plant-greenhouse interactions. It is disc

  17. 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.

  18. Film coating of seeds with Bacillus cereus RS87 spores for early plant growth enhancement.

    Science.gov (United States)

    Jetiyanon, Kanchalee; Wittaya-Areekul, Sakchai; Plianbangchang, Pinyupa

    2008-10-01

    The plant growth-promoting rhizobacterium Bacillus cereus RS87 was previously reported to promote plant growth in various crops in both greenhouse and field trials. To apply as a plant growth promoting agent with practical use, it is essential to ease the burden of routine preparation of a fresh suspension of strain RS87 in laboratory. The objectives of this study were to investigate the feasibility of film-coating seeds with B. cereus RS87 spores for early plant growth enhancement and to reveal the indoleacetic acid (IAA) production released from strain RS87. The experiment consisted of the following 5 treatments: nontreated seeds, water-soaked seeds, film-coated seeds, seeds soaked with vegetative cells of strain RS87, and film-coated seeds with strain RS87 spores. Three experiments were conducted separately to assess seed emergence, root length, and plant height. Results showed that both vegetative cells and spores of strain RS87 significantly promoted (P seed emergence, root length and plant height over the control treatments. The strain RS87 also produced IAA. In conclusion, the film coating of seeds with spores of B. cereus RS87 demonstrated early plant growth enhancement as well as seeds using their vegetative cells. IAA released from strain RS87 would be one of the mechanisms for plant growth enhancement.

  19. The Effect of Planting Date on the Growth and Yield of Indigo (Indigofera tinctoria L. in Shahrood Conditions

    Directory of Open Access Journals (Sweden)

    A Ansori

    2016-07-01

    increasing and x0 is the time of reaching plant to the maximum CGR. In this study, instead of day, we used growing degree days (GDD according to Equation 4: In this equation Tmax: maximum daily temperature, Tmin: minimum daily temperature, Tb: temperature of the plant, which was considered to indigo 10.27 °C (6. Fitting equations and drawing diagrams were performed using Sigma Plot 10 version. Analysis of variance and correlation between traits were performed using SAS software and means were compared using LSD test at the 5% level. Results and Discussion Results showed that (Figure 2a and Table 2 the earliest planting date (18 June increased total dry matter and crop growth rate about 4.41 and 3.59 folds compared to third planting date (18 July, respectively. In addition, the highest GDD was recorded for the first sowing date (18 June. The results showed that the fastest (38.34 and the lowest (12.37 growing rate was related to 18 June and 18 July planting dates, respectively (Table 3. Gupta (10 also stated that there was a significant correlation between sowing time and plant biological yield, as with delay in sowing date plant dry weight has been decreased. Mean comparison results showed that the lowest plant height was obtained at the early planting date (18 June and the lowest of it was seen in the late planting date (18 July (Figure 5 B. In the first planting date (18 June, biological yield increased 47.27% compared to the later planting date (18 July. In third sowing date biological yield decreased significantly than first and second planting dates (Figure 5 A. Zhelgazkov et al. (21 on Coriandrum sativum L. showed that the earliest cultivation increased the length of effective growth period and finally caused an increase in fruit and biological yield. The reason for reduction of biological yield in delayed cultivation in addition to shortening of growth season is related to coincidence of vegetative and reproduction period with summer heat which resulted in severe

  20. Growth and Contaminant Removal Effect of Several Plants in Constructed Wetlands

    Institute of Scientific and Technical Information of China (English)

    Xiu-Yun Cheng; Ming-Qiu Liang; Wen-Yin Chen; Xu-Cheng Liu; Zhang-He Chen

    2009-01-01

    The aim of the present study is to probe the relation between plant growth and its decontamination effect in constructed wetlands.Four species were studied in the small-scale mono-cuitured constructed wetlands, which were fed with domestic wastewater. Plant growth indexes were correlated with contaminant removal performance of the constructed wetlands. Wetlands planted with Cyperus flabelliformis Rottb. showed the highest growth indexes such as shoot growth, biomass, root activity, root biomass increment, and the highest contaminant removal rates, whereas wetlands planted with Vetiveria zizanioides L. Nash had the lowest growth indexes and the lowest removal rates. Above-ground biomass and total biomass were significantly correlated with ammonia nitrogen removal, and below-ground biomass with soluble reactive phosphorus removal. Photosynthetic rate had higher correlation with nitrogen removal in these species. Root activity and root biomass increment was more correlated with 5 d biochemical oxygen demand removal.Chemical oxygen demand removal had lower correlations with plant growth indexes. All four species had higher removal rates in summer and autumn. The results suggest that the effect of plant growth on contaminant removal in constructed wetlands were different specifically in plants and contaminants.

  1. Endophytic bacteria isolated from orchid and their potential to promote plant growth.

    Science.gov (United States)

    Faria, Deise Cristina; Dias, Armando Cavalcante Franco; Melo, Itamar Soares; de Carvalho Costa, Francisco Eduardo

    2013-02-01

    Twelve endophytic bacteria were isolated from the meristem of in vitro Cymbidium eburneum orchid, and screened according to indole yield quantified by colorimetric assay, in vitro phosphate solubilization, and potential for plant growth promotion under greenhouse conditions. Eight strains with positive results were classified into the genus Paenibacillus by FAME profile, and evaluated for their ability to increase survival and promote the growth of in vitro germinated Cattleya loddigesii seedlings during the acclimatization process. The obtained results showed that all strains produced detectable indole levels and did not exhibit potential for solubilizing inorganic phosphate. Particularly, an increase of the total biomass and number of leaves was observed. Two strains of Paenibacillus macerans promoted plant growth under greenhouse conditions. None of the treatments had a deleterious effect on growth of inoculated plants. These results suggest that these bacterial effects could be potentially useful to promote plant growth during seedling acclimatization in orchid species other than the species of origin.

  2. 78 FR 71676 - NUREG-1482, Revision 2, “Guidelines for Inservice Testing at Nuclear Power Plants, Final Report”

    Science.gov (United States)

    2013-11-29

    ... COMMISSION NUREG-1482, Revision 2, ``Guidelines for Inservice Testing at Nuclear Power Plants, Final Report.... Nuclear Regulatory Commission (NRC) has issued a final report entitled: NUREG-1482, Revision 2....'' In the previous Revisions 0 and 1 of NUREG-1482, the NRC staff provides licensees guidelines...

  3. Systemic Growth of F. graminearum in Wheat Plants and Related Accumulation of Deoxynivalenol

    Directory of Open Access Journals (Sweden)

    Antonio Moretti

    2014-04-01

    Full Text Available Fusarium head blight (FHB is an important disease of wheat worldwide caused mainly by Fusarium graminearum (syn. Gibberella zeae. This fungus can be highly aggressive and can produce several mycotoxins such as deoxynivalenol (DON, a well known harmful metabolite for humans, animals, and plants. The fungus can survive overwinter on wheat residues and on the soil, and can usually attack the wheat plant at their point of flowering, being able to infect the heads and to contaminate the kernels at the maturity. Contaminated kernels can be sometimes used as seeds for the cultivation of the following year. Poor knowledge on the ability of the strains of F. graminearum occurring on wheat seeds to be transmitted to the plant and to contribute to the final DON contamination of kernels is available. Therefore, this study had the goals of evaluating: (a the capability of F. graminearum causing FHB of wheat to be transmitted from the seeds or soil to the kernels at maturity and the progress of the fungus within the plant at different growth stages; (b the levels of DON contamination in both plant tissues and kernels. The study has been carried out for two years in a climatic chamber. The F. gramineraum strain selected for the inoculation was followed within the plant by using Vegetative Compatibility technique, and quantified by Real-Time PCR. Chemical analyses of DON were carried out by using immunoaffinity cleanup and HPLC/UV/DAD. The study showed that F. graminearum originated from seeds or soil can grow systemically in the plant tissues, with the exception of kernels and heads. There seems to be a barrier that inhibits the colonization of the heads by the fungus. High levels of DON and F. graminearum were found in crowns, stems, and straw, whereas low levels of DON and no detectable levels of F. graminearum were found in both heads and kernels. Finally, in all parts of the plant (heads, crowns, and stems at milk and vitreous ripening stages, and straw at

  4. Growth Promotion of Glycyrrhiza glabra L. by Salt-Tolerant Plant Growth Promotion Rhizobacteria under Saline Conditions

    Directory of Open Access Journals (Sweden)

    Jabborova D

    2016-04-01

    Full Text Available Salinity stress is one of the most serious factors limiting the productivity of agriculture. Plant growth promotion rhizobacteria (PGPR which produce phytohormones is one of the options to mitigate salt stress in plants and improve their growth and improvement under saline conditions. We study the effect of salt-tolerant P.putidaNUU8strain on plant growth of Glycyrrhizaglabra L. under saline soils. The treatment inoculation of P. putidaNUU8strainstatistically significantly increased roots and shoots length plant–1 over the control under a pot experiment. The results showed that inoculation of Glycyrrhizaglabra with of salt-tolerant P.putidaNUU8can enhance salt tolerance and plant growth under soil saline conditions. In our previous study we reported that the salinity did not inhibit the IAA production by strain. Strain P. putidaNUU8appeared to produce IAA in media contained NaCl up to 9 % and it was able to growth at high salt condition.Salt-stressed Glycyrrhizaglabra inoculated with the P. putidaNUU8sharply increased than uninoculated plants. Inoculation of P. putidaNUU8 strain significantly improved the root length 56% and shoots lenth 49% of Glycyrrhizaglabracompared with uninoculated control.

  5. Plant circadian clocks increase photosynthesis, growth, survival, and competitive advantage.

    Science.gov (United States)

    Dodd, Antony N; Salathia, Neeraj; Hall, Anthony; Kévei, Eva; Tóth, Réka; Nagy, Ferenc; Hibberd, Julian M; Millar, Andrew J; Webb, Alex A R

    2005-07-22

    Circadian clocks are believed to confer an advantage to plants, but the nature of that advantage has been unknown. We show that a substantial photosynthetic advantage is conferred by correct matching of the circadian clock period with that of the external light-dark cycle. In wild type and in long- and short-circadian period mutants of Arabidopsis thaliana, plants with a clock period matched to the environment contain more chlorophyll, fix more carbon, grow faster, and survive better than plants with circadian periods differing from their environment. This explains why plants gain advantage from circadian control.

  6. Review: Wind impacts on plant growth, mechanics and damage.

    Science.gov (United States)

    Gardiner, Barry; Berry, Peter; Moulia, Bruno

    2016-04-01

    Land plants have adapted to survive under a range of wind climates and this involve changes in chemical composition, physical structure and morphology at all scales from the cell to the whole plant. Under strong winds plants can re-orientate themselves, reconfigure their canopies, or shed needles, leaves and branches in order to reduce the drag. If the wind is too strong the plants oscillate until the roots or stem fail. The mechanisms of root and stem failure are very similar in different plants although the exact details of the failure may be different. Cereals and other herbaceous crops can often recover after wind damage and even woody plants can partially recovery if there is sufficient access to water and nutrients. Wind damage can have major economic impacts on crops, forests and urban trees. This can be reduced by management that is sensitive to the local site and climatic conditions and accounts for the ability of plants to acclimate to their local wind climate. Wind is also a major disturbance in many plant ecosystems and can play a crucial role in plant regeneration and the change of successional stage.

  7. Enhancement of plant growth and decontamination of nickel-spiked soil using PGPR.

    Science.gov (United States)

    Tank, Neelam; Saraf, Meenu

    2009-04-01

    Phytoremediation i.e. the use of plants to adsorb, accumulate or detoxify contaminants is an emerging area of interest. A viable technology needs optimum biomass production in metal contaminated soil. Five strains of microbes were selected after testing their potential as plant growth promoters, on the basis of their phosphate solubilization ability, IAA, siderophore and HCN production and biocontrol potentials. They were examined for growth in synthetic medium supplemented with nickel and their MIC (2 mM) was determined. These isolates were also able to grow and produce siderophores in presence of heavy metals like Ni, Zn and Cd. A positive response of bacterial inoculants was observed in chickpea plants towards toxic effect of nickel present in soil at different concentration (0, 1 and 2 mM). Bacterial inoculants enhanced fresh and dry weight of plants even at 2 mM nickel concentration. Pot experiments indicated that presence of nickel at upto 1 mM enhanced plant growth compared to uninoculated nickel free plants. The accumulation of nickel/plant was just 50% in Pseudomonas inoculated plants as compared to uninoculated plants with 2 mM nickel concentration along with increased biomass. The results suggest the use of these PGPR to enhance plant growth in nickel-spiked land and remediate nickel from contaminated sites. ((c) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim).

  8. Microbial Inoculation Improves Growth of Oil Palm Plants (Elaeis guineensis Jacq.).

    Science.gov (United States)

    Om, Azlin Che; Ghazali, Amir Hamzah Ahmad; Keng, Chan Lai; Ishak, Zamzuri

    2009-12-01

    Introduction of diazotrophic rhizobacteria to oil palm tissues during the in vitro micropropagation process establishes an early associative interaction between the plant cells and bacteria. In the association, the diazotrophs provide the host plants with phytohormones and fixed nitrogen. This study was conducted to observe growth of bacterised tissue cultured oil palm plants under ex vitro conditions after 280 days of growth. Root dry weight, shoot dry weight, root volume, bacterial colonisation, leaf protein and chlorophyll content of the host plants were observed. The results revealed that the inocula successfully colonised roots of the host plants. Plants inoculated with Acetobacter diazotrophicus (R12) had more root dry weight and volume than plants inoculated with Azospirillum brasilense (Sp7). Leaf protein and chlorophyll content were higher in the bacterised plants compared to Control 2 plants (inoculated with killed Sp7). These results suggest that the diazotrophs successfully improved the growth of the host plant (oil palm) and minimised the amount of N fertiliser necessary for growth.

  9. 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.

  10. Multi-trophic consequences of plant genetic variation in sex and growth.

    Science.gov (United States)

    Abdala-Roberts, Luis; Pratt, Jessica D; Pratt, Riley; Schreck, Tadj K; Hanna, Victoria; Mooney, Kailen A

    2016-03-01

    There is growing evidence for the influence of plant intraspecific variation on associated multi-trophic communities, but the traits driving such effects are largely unknown. We conducted a field experiment with selected genetic lines of the dioecious shrub Baceharis salicifolia to investigate the effects of plant growth rate (two-fold variation) and gender (males vs. females of the same growth rate) on above- and belowground insect and fungal associates. We documented variation in associate density to test for effects occurring through plant-based habitat quality (controlling for effects of plant size) as well as variation in associate abundance to test for effects occurring through both habitat quality and abundance (including effects of plant size). Whereas the dietary specialist aphid Uroleucon macaolai was unaffected by plant sex and growth rate, the generalist aphid Aphis gossypii and its tending ants (Linepithema humile) had higher abundances and densities on male (vs. female) plants, suggesting males provide greater habitat quality. In contrast, Aphis and ant abundance and density were unaffected by plant growth rate, while Aphis parasitoids were unaffected by either plant sex or growth rate. Arbuscular mycorrhizal fungi had higher abundance and density (both marginally significant) on females (vs. males), suggesting females provide greater habitat quality, but lower abundances (marginally significant) and higher densities on slow- (vs. fast-) growing genotypes, suggesting slow-growing genotypes provided lower resource abundance but greater habitat quality. Overall, plant sex and growth rate effects on associates acted independently (i.e., no interactive effects), and these effects were of a greater magnitude than those coming from other axes of plant genetic variation. These findings thus demonstrate that plant genetic effects on associated communities may be driven by a small number of trait-specific mechanisms.

  11. Effect of plant growth regulators on leaf anatomy of the has mutant of Arabidopsis thaliana.

    Science.gov (United States)

    Janosević, D; Uzelac, B; Budimir, S

    2008-12-01

    In this study, the effect of plant growth regulators on leaf morphogenesis of the recessive T-DNA insertion mutant of Arabidopsis thaliana was analyzed. The morpho-anatomical analysis revealed that leaves of the has mutant are small and narrow, with lobed blades and disrupted tissue organization. When has plants were grown on the medium supplied with plant growth regulators: benzylaminopurine (BAP) or ethylene precursor, 1-aminocyclopropane-1-carboxylic acid (ACC), the leaf anatomy was partially restored to the wild type, although plants still exhibited morphological abnormalities.

  12. Rhizobacterial Strain Bacillus megaterium BOFC15 Induces Cellular Polyamine Changes that Improve Plant Growth and Drought Resistance

    OpenAIRE

    Cheng Zhou; Zhongyou Ma; Lin Zhu; Xin Xiao; Yue Xie; Jian Zhu; Jianfei Wang

    2016-01-01

    Plant-growth-promoting rhizobacteria can improve plant growth, development, and stress adaptation. However, the underlying mechanisms are still largely unclear. We investigated the effects of Bacillus megaterium BOFC15 on Arabidopsis plants. BOFC15 produced and secreted spermidine (Spd), a type of polyamine (PA) that plays an important role in plant growth. Moreover, BOFC15 induced changes in the cellular PAs of plants that promoted an increase of free Spd and spermine levels. However, these ...

  13. [Effect of different plant growth regulators on yield and quality of Angelica dahurica var. formosana development].

    Science.gov (United States)

    Hou, Kai; Chen, Jun-Wen; Zhai, Juan-Yuan; Shen, Hao; Chen, Li; Wu, Wei

    2013-07-01

    To investigate the effect of plant growth regulators on the growth and quality of Angelica dahurica var. formosana. Five plant growth regulators: chlormequat chloride (CCC), Mepiquat chloride (PIX), Gibberellic acid (GA3), Paclobutrazol (PP333) and Maleic Hydrazide (MH) were sprayed in rosette stage, the effects of these plant growth regulators (PGRs) on the growth, yield and quality of A. dahurica var. formosanaw were observed. The biological traits were first measured and then imperatorin and isoimperatorin contents in roots were determined by HPLC. Low concentration GA3 increased the yield while not influenced the premature bolting rate and the coumarin content. Spraying of GA3 (30 mg x L(-1)) could guarantee the growth and development of A. dahurica var. formosana to have a higher yield and maintain the active ingredients content in the root as well.

  14. The effect of Bt-transgene introgression on plant growth and reproduction in wild Brassica juncea.

    Science.gov (United States)

    Liu, Yong-Bo; Darmency, Henry; Stewart, C Neal; Wei, Wei; Tang, Zhi-Xi; Ma, Ke-Ping

    2015-06-01

    This study aims to investigate the relative plant growth and reproduction of insect-resistant and susceptible plants following the introgression of an insect-resistance Bt-transgene from Brassica napus, oilseed rape, to wild Brassica juncea. The second backcrossed generation (BC2) from a single backcross family was grown in pure and mixed stands of Bt-transgenic and non-transgenic siblings under two insect treatments. Various proportions of Bt-transgenic plants were employed in mixed stands to study the interaction between resistant and susceptible plants. In the pure stands, Bt-transgenic BC2 plants performed better than non-transgenic plants with or without insect treatments. In mixed stands, Bt-transgenic BC2 plants produced fewer seeds than their non-Bt counterparts at low proportions of Bt-transgenic BC2 plants in the absence of insects. Reproductive allocation of non-transgenic plants marginally increased with increasing proportions of Bt-transgenic plants under herbivore pressure, which resulted in increased total biomass and seed production per stand. The results showed that the growth of non-transgenic plants was protected by Bt-transgenic plants under herbivore pressure. The Bt-transgene might not be advantageous in mixed stands of backcrossed hybrids; thus transgene introgression would not be facilitated when herbivorous insects are not present. However, a relatively large initial population of Bt-transgenic plants might result in transgene persistence when target herbivores are present.

  15. Plant growth simulation for landscape scale hydrologic modeling

    Science.gov (United States)

    Landscape scale hydrologic models can be improved by incorporating realistic, process-oriented plant models for simulating crops, grasses, and woody species. The objective of this project was to present some approaches for plant modeling applicable to hydrologic models like SWAT that can affect the...

  16. Effect Of Cowpea Planting Density On Growth, Yield And ...

    African Journals Online (AJOL)

    ... per hectare was intercropped with cowpea at four planting densities (20,000; 40,000; ... Cowpea LAI was similar in the 2 seasons with the highest planting density ... and population density in 2005/2006, but not in 2004/2005 cropping season. ... AJOL jobs · More about AJOL · AJOL's Partners · Contact AJOL · Terms and ...

  17. Growth and morphogenesis of sun and shade plants

    NARCIS (Netherlands)

    Corre, W.J.

    1984-01-01

    A number of species of sun and shade plants in the vegetative phase were grown in different light intensities, different light qualities (r/fr ratio) and different combinations of light intensity and nutrient supply. Sun and shade species were also grown at various plant densities and in interspecif

  18. 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.

  19. Influence of plant population and nitrogen-fertilizer at various levels on growth and growth efficiency of maize.

    Science.gov (United States)

    Tajul, M I; Alam, M M; Hossain, S M M; Naher, K; Rafii, M Y; Latif, M A

    2013-01-01

    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 800,000 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.

  20. 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.

  1. Biological effects of native and exotic plant residues on plant growth, microbial biomass and N availability under controlled conditions

    OpenAIRE

    Diallo, Mariama-Dalanda; Duponnois, Robin; Guisse, A.; Sall, Saïdou; Chotte, Jean-Luc; Thioulouse, J.

    2006-01-01

    The leaf litter of six tropical tree species (Acacia holosericea, Acacia tortilis, Azadirachta indica, Casuarina equisetifolia, Cordyla pinnata and Faidherbia albida) frequently used in agroforestry plantations in Sahelian and Soudano-Sahelian areas were tested for their influence on soil nitrogen content, microbial biomass and plant growth under controlled greenhouse conditions. Half of the soil was planted with onion (Allium cepa L.) seedlings and the other half was not. Two herbaceous spec...

  2. 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)

  3. 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.

  4. Plant defense, herbivory, and the growth of Cordia alliodora trees and their symbiotic Azteca ant colonies.

    Science.gov (United States)

    Pringle, Elizabeth G; Dirzo, Rodolfo; Gordon, Deborah M

    2012-11-01

    The effects of herbivory on plant fitness are integrated over a plant's lifetime, mediated by ontogenetic changes in plant defense, tolerance, and herbivore pressure. In symbiotic ant-plant mutualisms, plants provide nesting space and food for ants, and ants defend plants against herbivores. The benefit to the plant of sustaining the growth of symbiotic ant colonies depends on whether defense by the growing ant colony outpaces the plant's growth in defendable area and associated herbivore pressure. These relationships were investigated in the symbiotic mutualism between Cordia alliodora trees and Azteca pittieri ants in a Mexican tropical dry forest. As ant colonies grew, worker production remained constant relative to ant-colony size. As trees grew, leaf production increased relative to tree size. Moreover, larger trees hosted lower densities of ants, suggesting that ant-colony growth did not keep pace with tree growth. On leaves with ants experimentally excluded, herbivory per unit leaf area increased exponentially with tree size, indicating that larger trees experienced higher herbivore pressure per leaf area than smaller trees. Even with ant defense, herbivory increased with tree size. Therefore, although larger trees had larger ant colonies, ant density was lower in larger trees, and the ant colonies did not provide sufficient defense to compensate for the higher herbivore pressure in larger trees. These results suggest that in this system the tree can decrease herbivory by promoting ant-colony growth, i.e., sustaining space and food investment in ants, as long as the tree continues to grow.

  5. 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.

  6. Exopolysaccharide-Producing Plant Growth-Promoting Rhizobacteria Under Salinity Condition

    Institute of Scientific and Technical Information of China (English)

    S. K. UPADHYAY; J. S. SINGH; D. P. SINGH

    2011-01-01

    Salt-tolerant plant growth-promoting rhizobacteria (PGPR) can play an important role in alleviating soil salinity stress during plant growth and bacterial exopolysaccharide (EPS) can also help to mitigate salinity stress by reducing the content of Na+ available for plant uptake. In this study, native bacterial strains of wheat rhizosphere in soils of Varanasi, India, were screened to identify the EPS-producing salt-tolerant rhizobacteria with plant growth-promoting traits. The various rhizobacteria strains were isolated and identified using 16S rDNA sequencing. The plant growth-promoting effect of inoculation of seedlings with these bacterial strains was evaluated under soil salinity conditions in a pot experiment. Eleven bacterial strains which initially showed tolerance up to 80 g L-1 NaCl also exhibited an EPS-producing potential. The results suggested that the isolated bacterial strains demonstrated some of the plant growth-promoting traits such as phosphate solubilizing ability and production of auxin, proline, reducing sugars, and total soluble sugars, Furthermore, the inoculated wheat plants had an increased biomass compared to the un-inoculated plants.

  7. Plant growth promotion by spermidine-producing Bacillus subtilis OKB105.

    Science.gov (United States)

    Xie, Shan-Shan; Wu, Hui-Jun; Zang, Hao-Yu; Wu, Li-Ming; Zhu, Qing-Qing; Gao, Xue-Wen

    2014-07-01

    The interaction between plants and plant-growth-promoting rhizobacteria (PGPR) is a complex, reciprocal process. On the one hand, plant compounds such as carbohydrates and amino acids serve as energy sources for PGPR. On the other hand, PGPR promote plant growth by synthesizing plant hormones and increasing mineral availability in the soil. Here, we evaluated the growth-promoting activity of Bacillus subtilis OKB105 and identified genes associated with this activity. The genes yecA (encoding a putative amino acid/polyamine permease) and speB (encoding agmatinase) are involved in the secretion or synthesis of polyamine in B. subtilis OKB105. Disruption of either gene abolished the growth-promoting activity of the bacterium, which was restored when polyamine synthesis was complemented. Moreover, high-performance liquid chromatography analysis of culture filtrates of OKB105 and its derivatives demonstrated that spermidine, a common polyamine, is the pivotal plant-growth-promoting compound. In addition, real-time polymerase chain reaction analysis revealed that treatment with B. subtilis OKB105 induced expansin gene (Nt-EXPA1 and Nt-EXPA2) expression and inhibited the expression of the ethylene biosynthesis gene ACO1. Furthermore, enzyme-linked immunosorbent assay analysis showed that the ethylene content in plant root cells decreased in response to spermidine produced by OKB105. Therefore, during plant interactions, OKB105 may produce and secrete spermidine, which induces expansin production and lowers ethylene levels.

  8. Inference of allelopathy is complicated by effects of activated carbon on plant growth.

    Science.gov (United States)

    Lau, Jennifer A; Puliafico, Kenneth P; Kopshever, Joseph A; Steltzer, Heidi; Jarvis, Edward P; Schwarzländer, Mark; Strauss, Sharon Y; Hufbauer, Ruth A

    2008-01-01

    Allelopathy can play an important role in structuring plant communities, but allelopathic effects are often difficult to detect because many methods used to test for allelopathy can be confounded by experimental artifacts. The use of activated carbon, a technique for neutralizing allelopathic compounds, is now employed in tests for allelopathy; however, this technique also could produce large experimental artifacts. In three independent experiments, it was shown that adding activated carbon to potting media affected nutrient availability and plant growth. For most species tested, activated carbon increased plant biomass, even in the absence of the potentially allelopathic agent. The increased growth corresponded to increased plant nitrogen content, likely resulting from greater nitrogen availability. Activated carbon also affected nitrogen and other nutrient concentrations in soil media in the absence of plants. The observed effects of activated carbon on plant growth can confound its use to test for allelopathy. The detection of allelopathy relies on the difference between plant growth in medium with carbon and that in medium without carbon in the presence of the potentially allelopathic competitor; however, this difference may be biased if activated carbon alters soil nutrient availability and plant growth even in the absence of the focal allelopathic agent.

  9. Modeling of integrated environmental control systems for coal-fired power plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, E.S.; Salmento, J.S.; Frey, H.C.; Abu-Baker, A.; Berkenpas, M.

    1991-05-01

    The Integrated Environmental Control Model (IECM) was designed to permit the systematic evaluation of environmental control options for pulverized coal-fired (PC) power plants. Of special interest was the ability to compare the performance and cost of advanced pollution control systems to ``conventional`` technologies for the control of particulate, SO{sub 2} and NO{sub x}. Of importance also was the ability to consider pre-combustion, combustion and post-combustion control methods employed alone or in combination to meet tough air pollution emission standards. Finally, the ability to conduct probabilistic analyses is a unique capability of the IECM. Key results are characterized as distribution functions rather than as single deterministic values. (VC)

  10. 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.

  11. 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.

  12. Plant growth depressions in arbuscular mycorrhizal symbioses: not just caused by carbon drain?

    Science.gov (United States)

    Li, Huiying; Smith, F Andrew; Dickson, Sandy; Holloway, Robert E; Smith, Sally E

    2008-01-01

    * This study investigated effects of plant density and arbuscular mycorrhizal (AM) colonization on growth and phosphorus (P) nutrition of a cultivar of wheat (Triticum aestivum) that often shows early AM-induced growth depressions. * Two experiments were conducted. Expt 1 had three plant densities and one soil P concentration. Expt 2 had two plant densities and two P concentrations. Plants were grown in calcareous P-fixing soil, inoculated with Glomus intraradices or Gigaspora margarita, or noninoculated (nonmycorrhizal (NM)). Glomus intraradices colonized well and caused a growth depression only in Expt 1. Gigaspora margarita caused large growth depressions in both experiments even though it colonized poorly. * The results showed that growth depressions were mitigated by changes in relative competition for soil P by NM and AM plants, and probably by decreasing carbon costs of the fungi. * The different effects of the two fungi appear to be attributable to differences in the balance between P uptake by the fungal pathway and direct uptake via the roots. These differences may be important in other AM symbioses that result in growth depressions. The results show that mycorrhizal growth responses of plants grown singly may not apply at the population or community level.

  13. 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.

  14. Aquatic Plant Control Research Program. Effects of Water Chemistry on Aquatic Plants. Growth and Photosynthesis of Myriophyllum spicatum L.

    Science.gov (United States)

    1986-05-01

    A D-A±69 98 AQUATIC PLANT CONTROL RESEARCH PRGRAM EFFECTS OF N*TER 1 I CHEMISTRY ON AQUA .(U) ARMY ENGINEER NATERNAYS I EXPERIMENT STATION VICKSBURG...photosynthesis should be clearly resolved. Objective and Scope 6. The objective of this report is to evaluate the effects of major cation and inorganic...carbon levels on the growth and photosynthesis of M. spicaturn. A secondary objective is to evaluate the relationship between growth and

  15. Functional compatibility in cucumber mycorrhizas in terms of plant growth performance and foliar nutrient composition.

    Science.gov (United States)

    Ravnskov, S; Larsen, J

    2016-09-01

    Functional compatibility in cucumber mycorrhizas in terms of plant and fungal growth, and foliar nutrient composition from all possible combinations of six cucumber varieties and three species of arbuscular mycorrhizal (AM) fungi was evaluated. Measurements of foliar nutrient composition included N, P, K, Mg, Ca, Na, Fe, Zn, Mn and Cu. Growth of AM fungi was measured in terms of root colonisation, as examined with microscopy and the AM fungus biomarker fatty acid 16:1ω5 from both phospholipids and neutral lipids. Different responses of plant growth and foliar nutrient profiles were observed for the different AM symbioses examined. The AM fungus Claroideoglomus claroideum caused growth depression in association with four out of six cucumber varieties; Rhizophagus irregularis caused growth promotion in one of six cucumber varieties; whereas Funneliformis mosseae had no effect on the growth performance of any of the cucumber varieties examined. All three AM fungi markedly altered host plant shoot nutrient composition, with the strongest contrast observed between cucumber-R. irregularis symbioses and non-mycorrhizal cucumber plants, independent of cucumber variety. On the other hand, AM fungal growth in roots differed between the three AM fungi, but was unaffected by host genotype. Strong build-up of storage lipids was observed for R. irregularis, which was more moderate in the two other AM fungi. In conclusion, strong differential responses of cucumber varieties to inoculation with different AM fungi in terms of growth and shoot nutrient composition revealed high functional diversity in AM symbioses in cucumber plants.

  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. Integral Parameters for Characterizing Water, Energy, and Aeration Properties of Soilless Plant Growth Media

    DEFF Research Database (Denmark)

    Deepagoda Thuduwe Kankanamge Kelum, Chamindu; Lopez, Jose Choc Chen; Møldrup, Per

    2013-01-01

    systems are regaining increased worldwide attention. The optimal control of water availability and aeration is an essential prerequisite to successfully operate plant growth systems with soilless substrates such as aggregated foamed glass, perlite, rockwool, coconut coir, or mixtures thereof. While...

  18. Growth responses of NaCl stressed rice (Oryza sativa L.) plants ...

    African Journals Online (AJOL)

    GREGORY

    2010-09-27

    Sep 27, 2010 ... Effect of salinity (NaCl) in the presence of proline was assessed .... factors, with salinity being considered as a major constraint. (Ashraf, 2004 ... conditions) to increase the plant growth rate than saline ..... Photosynthetic.

  19. Plant growth-promoting potential of endophytic fungi isolated from Solanum nigrum leaves.

    Science.gov (United States)

    Khan, Abdur Rahim; Ullah, Ihsan; Waqas, Muhammad; Shahzad, Raheem; Hong, Sung-Jun; Park, Gun-Seok; Jung, Byung Kwon; Lee, In-Jung; Shin, Jae-Ho

    2015-09-01

    Fungal endophytes have been characterized as producers of phytohormones and potent promoters of plant growth. In this study, two fungal endophytes, Fusarium tricinctum RSF-4L and Alternaria alternata RSF-6L, were isolated from the leaves of Solanum nigrum. Culture filtrates (CFs) from each isolate were initially screened for indole compounds, and assayed for their ability to promote the growth of Dongjin rice plants. Nearly all plant growth attributes examined (i.e., chlorophyll content, root-shoot length, and biomass production) were significantly enhanced upon treatment with fungal CFs. Subsequently, gas chromatography/mass spectrometry analyses were utilized to confirm the presence of phytohormones in the CF of each fungal endophytic isolate. These analyses revealed that RSF-4L and RSF-6L produced 54 and 30 µg/mL indole acetic acid, respectively, within their respective cultures. These findings suggest that the endophytes isolated in this study synthesize bioactive compounds that could play important roles in promoting plant growth.

  20. Effect of plant growth regulators and activated charcoal on in vitro ...

    African Journals Online (AJOL)

    Administrator

    2011-07-15

    Jul 15, 2011 ... Key words: Activated charcoal, oil palm, plant growth regulators, zygotic embryo. ... all the essential mineral ions, carbon source, vitamins and other organic supplements .... (2010), where MS medium fortified with a low level of ...

  1. Indirect Contributions of AM Fungi and Soil Aggregation to Plant Growth and Protection

    Science.gov (United States)

    Soil ecological and biological engineering are processes by which soil organisms modify their physiochemical environment resulting indirectly to enhancements in plant growth. The formation and stabilization of soil aggregates is an example biologically-mediated engineering. For soil organisms, wate...

  2. Modeling gravity effects on water retention and gas transport characteristics in plant growth substrates

    DEFF Research Database (Denmark)

    Deepagoda Thuduwe Kankanamge Kelum, Chamindu; Jones, Scott B.; Tuller, Markus

    2014-01-01

    Growing plants to facilitate life in outer space, for example on the International Space Station (ISS) or at planned deep-space human outposts on the Moon or Mars, has received much attention with regard to NASA’s advanced life support system research. With the objective of in situ resource...... utilization to conserve energy and to limit transport costs, native materials mined on Moon or Mars are of primary interest for plant growth media in a future outpost, while terrestrial porous substrates with optimal growth media characteristics will be useful for onboard plant growth during space missions...... permeability characteristics of six plant growth substrates for potential applications in space, including two terrestrial analogs for lunar and Martian soils and four particulate substrates widely used in reduced gravity experiments. To simulate reduced gravity water characteristics, the predictions...

  3. Integrated LED/Imaging Illumination Panels Demonstrated within a Small Plant Growth Chamber Project

    Data.gov (United States)

    National Aeronautics and Space Administration — LED light sources are ideal for plant growth systems. However, commercially available multi-color LED illumination panels are designed and manufactured to produce a...

  4. Plant Growth-Promoting Rhizobacteria Enhance Salinity Stress Tolerance in Okra through ROS-Scavenging Enzymes.

    Science.gov (United States)

    Habib, Sheikh Hasna; Kausar, Hossain; Saud, Halimi Mohd

    2016-01-01

    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.

  5. Evaluation of absorption of radionuclides via roots of plants at different growth stages

    Energy Technology Data Exchange (ETDEWEB)

    Ambe, Shizuko [Institute of Physical and Chemical Research, Wako, Saitama (Japan)

    1999-03-01

    For the environmental risk assessment of radionuclides and toxic elements which were released by nuclear power plants and factories, the absorption of trace elements by plants has been studied by a multitracer technique. The selective absorption coefficient, which is a parameter of an uptake model of radionuclides by plants, was determined for various radionuclides. The selective absorption coefficients of some elements varied greatly in experimental runs. Therefore, the selective absorption coefficients of radionuclides by komatsuna at different growth stages were determined. Moreover, the soil-to-plant transfer of radionuclides in komatsuna at different growth stages was studied. Extraction of the radionuclides from the soil was carried out in order to study the correlation between the transfer factor and the aging effect of the radionuclides in soil. The effect of soil acidity on the absorption of radionuclides in soybean and tomato was studied using the plants at different growth stages. (author)

  6. Increased plant productivity and decreased microbial respiratory C loss by plant growth-promoting rhizobacteria under elevated CO₂.

    Science.gov (United States)

    Nie, Ming; Bell, Colin; Wallenstein, Matthew D; Pendall, Elise

    2015-03-18

    Increased plant productivity and decreased microbial respiratory C loss can potentially mitigate increasing atmospheric CO₂, but we currently lack effective means to achieve these goals. Soil microbes may play critical roles in mediating plant productivity and soil C/N dynamics under future climate scenarios of elevated CO₂ (eCO₂) through optimizing functioning of the root-soil interface. By using a labeling technique with (13)C and (15)N, we examined the effects of plant growth-promoting Pseudomonas fluorescens on C and N cycling in the rhizosphere of a common grass species under eCO₂. These microbial inoculants were shown to increase plant productivity. Although strong competition for N between the plant and soil microbes was observed, the plant can increase its capacity to store more biomass C per unit of N under P. fluorescens addition. Unlike eCO₂ effects, P. fluorescens inoculants did not change mass-specific microbial respiration and accelerate soil decomposition related to N cycling, suggesting these microbial inoculants mitigated positive feedbacks of soil microbial decomposition to eCO₂. The potential to mitigate climate change by optimizing soil microbial functioning by plant growth-promoting Pseudomonas fluorescens is a prospect for ecosystem management.

  7. Influence of nutrient composition and plant growth regulators on callus induction and plant regeneration in glutinous rice (Oryza sativa L.).

    Science.gov (United States)

    Duangsee, K; Bunnag, S

    2014-01-01

    The potential for callus induction and regeneration depends on nutrient composition and plant growth regulators. The aim of the present study was to investigate the effect of nutrient composition and plant growth regulators on callus induction and plant regeneration in the glutinous rice cultivar Khunvang. The effect of 2,4-D concentrations (1, 2, 3, 4 and 5 mg L(-1)) on callus induction and growth were investigated. The results revealed that the highest percentage of callus induction (97%) was observed in MS medium supplemented with 5 mg L(-1) 2,4-D under 16 h Photoperiod. The effects of casein hydrolysate concentrations of casein hydrolysate (0, 300, 500, 700 and 900 mg L(-1)) and proline (0, 300, 500, 700 and 900 mg L(-1)) on callus induction and growth of Khunvang were also observed. The results indicated that the increasing casein hydrolysate and proline concentrations did not show a significant effect on callus growth. However, proline concentration of 900 mg L(-1) yielded 85.67% of callus growth.

  8. Isolation and identification of plant growth promoting rhizobacteria from cucumber rhizosphere and their effect on plant growth promotion and disease suppression

    Directory of Open Access Journals (Sweden)

    Shaikhul eIslam

    2016-02-01

    Full Text Available Plant growth promoting rhizobacteria (PGPR are the rhizosphere bacteria that may be utilized to augment plant growth and suppress plant diseases. The objectives of this study were to identify and characterize PGPR indigenous to cucumber rhizosphere in Bangladesh, and to evaluate their ability to suppress Phytophthora crown rot in cucumber. A total of sixty six isolates were isolated, out of which ten (PPB1, PPB2, PPB3, PPB4, PPB5, PPB8, PPB9, PPB10, PPB11 and PPB12 were selected based on their in vitro plant growth promoting attributes and antagonism of phytopathogens. Phylogenetic analysis of 16S rRNA sequences identified these isolates as new strains of Pseudomonas stutzeri, Bacillus subtilis, Stenotrophomonas maltophilia and B. amyloliquefaciens. The selected isolates produced high levels (26.78 to 51.28 μg mL−1 of indole-3-acetic acid, while significant acetylene reduction activities (1.79 to 4.9 µmole C2H4 mg-1 protein h-1 were observed in eight isolates. Cucumber plants grown from seeds that were treated with these PGPR strains displayed significantly higher levels of germination, seedling vigor, growth, and N content in root and shoot tissue compared to non-treated control plants. All selected isolates were able to successfully colonize the cucumber roots. Moreover, treating cucumber seeds with these isolates significantly suppressed Phytophthora crown rot caused by Phytophthora capsici, and characteristic morphological alterations in Ph. capsici hyphae that grew towards PGPR colonies were observed. Since these PGPR inoculants exhibited multiple traits beneficial to the host plants, they may be applied in the development of new, safe, and effective seed treatments as an alternative to chemical fungicides.

  9. Combined inoculation of Pseudomonas fluorescens and Trichoderma harzianum for enhancing plant growth of vanilla (Vanilla planifolia).

    Science.gov (United States)

    Sandheep, A R; Asok, A K; Jisha, M S

    2013-06-15

    This study was conducted to evaluate the plant growth promoting efficiency of combined inoculation of rhizobacteria on Vanilla plants. Based on the in vitro performance of indigenous Trichoderma spp. and Pseudomonas spp., four effective antagonists were selected and screened under greenhouse experiment for their growth enhancement potential. The maximum percentage of growth enhancement were observed in the combination of Trichoderma harzianum with Pseudomonas fluorescens treatment followed by Pseudomonas fluorescens, Trichoderma harzianum, Pseudomonas putida and Trichoderma virens, respectively in decreasing order. Combined inoculation of Trichoderma harzianum and Pseudomonas fluorescens registered the maximum length of vine (82.88 cm), highest number of leaves (26.67/plant), recorded the highest fresh weight of shoots (61.54 g plant(-1)), fresh weight of roots (4.46 g plant(-1)) and dry weight of shoot (4.56 g plant(-1)) where as the highest dry weight of roots (2.0806 g plant(-1)) were achieved with treatments of Pseudomonas fluorescens. Among the inoculated strains, combined inoculation of Trichoderma harzianum and Pseudomonas fluorescens recorded the maximum nitrogen uptake (61.28 mg plant(-1)) followed by the combined inoculation of Trichoderma harzianum (std) and Pseudomonas fluorescens (std) (55.03 mg plant(-1)) and the highest phosphorus uptake (38.80 mg plant(-1)) was recorded in dual inoculation of Trichoderma harzianum and Pseudomonas fluorescens.

  10. Does ozone exposure alter growth and carbon allocation of mycorrhizal plants

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, L.C.; Gamon, J.A. (California State Univ., Los Angeles, CA (United States)); Andersen, C.P. (Environmental Protection Agency, Corvallis, OR (United States))

    1994-06-01

    Ozone is known to adversely affect plant growth. However, it is less clear how ozone affects belowground processes. This study tests the hypothesis that ozone alters growth and carbon allocation of vesicular arbuscular mycorrhizal (VAM) plants. Two ecotypes of Elymus glaucus (blue wild rye) were exposed to mycorrhizal inoculation and episodic ozone exposures simulating atmospheric conditions in the Los Angeles Basin. Preliminary results show that effects of ozone on growth were subtle. In both ecotypes, growth of aboveground biomass was not affected by ozone while root growth was decreased. In most treatments, mycorrhizal inoculation decreased growth of leaves and stems, but had no significant effect on root growth. Three-way ANOVA tests indicated interactive effects between ecotype, mycorrhiza and ozone. Further experimental work is needed to reveal the biological processes governing these responses.

  11. Soil inoculation with symbiotic microorganisms promotes plant growth and nutrient transporter genes expression in durum wheat.

    Science.gov (United States)

    Saia, Sergio; Rappa, Vito; Ruisi, Paolo; Abenavoli, Maria Rosa; Sunseri, Francesco; Giambalvo, Dario; Frenda, Alfonso S; Martinelli, Federico

    2015-01-01

    In a field experiment conducted in a Mediterranean area of inner Sicily, durum wheat was inoculated with plant growth-promoting rhizobacteria (PGPR), with arbuscular mycorrhizal fungi (AMF), or with both to evaluate their effects on nutrient uptake, plant growth, and the expression of key transporter genes involved in nitrogen (N) and phosphorus (P) uptake. These biotic associations were studied under either low N availability (unfertilized plots) and supplying the soil with an easily mineralizable organic fertilizer. Regardless of N fertilization, at the tillering stage, inoculation with AMF alone or in combination with PGPR increased the aboveground biomass yield compared to the uninoculated control. Inoculation with PGPR enhanced the aboveground biomass yield compared to the control, but only when N fertilizer was added. At the heading stage, inoculation with all microorganisms increased the aboveground biomass and N. Inoculation with PGPR and AMF+PGPR resulted in significantly higher aboveground P compared to the control and inoculation with AMF only when organic N was applied. The role of microbe inoculation in N uptake was elucidated by the expression of nitrate transporter genes. NRT1.1, NRT2, and NAR2.2 were significantly upregulated by inoculation with AMF and AMF+PGPR in the absence of organic N. A significant down-regulation of the same genes was observed when organic N was added. The ammonium (NH4 (+)) transporter genes AMT1.2 showed an expression pattern similar to that of the NO3 (-) transporters. Finally, in the absence of organic N, the transcript abundance of P transporters Pht1 and PT2-1 was increased by inoculation with AMF+PGPR, and inoculation with AMF upregulated Pht2 compared to the uninoculated control. These results indicate the soil inoculation with AMF and PGPR (alone or in combination) as a valuable option for farmers to improve yield, nutrient uptake, and the sustainability of the agro-ecosystem.

  12. Influence of plant growth regulators on indirect shoot organogenesis ...

    African Journals Online (AJOL)

    admin

    2013-10-17

    Oct 17, 2013 ... subalpine and alpine areas of Indian Himalayan Region at 3500-4000 m elevations, ... cytokinins and auxins) are often added to culture media ..... and cytokinin in the regulation of metabolism and development. Trend Plant ...

  13. Plant growth promoting rhizobacteria: Beneficial effects for healthy ...

    African Journals Online (AJOL)

    PROMOTING ACCESS TO AFRICAN RESEARCH ... These mechanisms were grouped into three clusters according to the PGPR effects on plant physiology. ... of antibiotics, lytic enzymes, hydrogen cyanide and volatile compounds. In view of ...

  14. Influence of plant growth regulators on axillary shoot multiplication ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-12-17

    Dec 17, 2008 ... Key words: Chlorosis, conservation, endangered plants, in vitro propagation, nodal explants, ... The medium consisted of MS basal salts and vitamins supple- ..... Maximum rooting was obtained on MMS medium fortified.

  15. Bromeliad-living spiders improve host plant nutrition and growth.

    Science.gov (United States)

    Romero, Gustavo Q; Mazzafera, Paulo; Vasconcellos-Neto, Joao; Trivelin, Paulo C O

    2006-04-01

    Although bromeliads are believed to obtain nutrients from debris deposited by animals in their rosettes, there is little evidence to support this assumption. Using stable isotope methods, we found that the Neotropical jumping spider Psecas chapoda (Salticidae), which lives strictly associated with the terrestrial bromeliad Bromelia balansae, contributed 18% of the total nitrogen of its host plant in a greenhouse experiment. In a one-year field experiment, plants with spiders produced leaves 15% longer than plants from which the spiders were excluded. This is the first study to show nutrient provisioning in a spider-plant system. Because several animal species live strictly associated with bromeliad rosettes, this type of facultative mutualism involving the Bromeliaceae may be more common than previously thought.

  16. The cytoskeleton in plant and fungal cell tip growth

    NARCIS (Netherlands)

    Geitmann, A.; Emons, A.M.C.

    2000-01-01

    Tip-growing cells have a particular lifestyle that is characterized by the following features: (1) the cells grow in one direction, forming a cylindrical tube; (2) tip-growing cells are able to penetrate their growth environment, thus having to withstand considerable external forces; (3) the growth

  17. Invasive plant suppresses the growth of native tree seedlings by disrupting belowground mutualisms.

    Directory of Open Access Journals (Sweden)

    Kristina A Stinson

    2006-05-01

    Full Text Available The impact of exotic species on native organisms is widely acknowledged, but poorly understood. Very few studies have empirically investigated how invading plants may alter delicate ecological interactions among resident species in the invaded range. We present novel evidence that antifungal phytochemistry of the invasive plant, Alliaria petiolata, a European invader of North American forests, suppresses native plant growth by disrupting mutualistic associations between native canopy tree seedlings and belowground arbuscular mycorrhizal fungi. Our results elucidate an indirect mechanism by which invasive plants can impact native flora, and may help explain how this plant successfully invades relatively undisturbed forest habitat.

  18. Effects of Red Light Night Break Treatment on Growth and Flowering of Tomato Plants

    OpenAIRE

    Kai eCao; Lirong eCui; Lin eYe; Xiaoting eZhou; Encai eBao; Hailiang eZhao; Zhirong eZou

    2016-01-01

    Compact and healthy young plants increase crop production and improve vegetable quality. Adverse climatic conditions and shading can cause young plants to become elongated and spindly. We investigated the effects of night break (NB) treatments on tomato plants using red light (RL) with an intensity of 20 µmol•m2•s-1. Tomato plants were subjected to NB treatments with different frequencies ranging from every 1, 2, 3, and 4 h, and plant growth, flowering, and yield were monitored. The results s...

  19. Onion seed vigor in relation to plant growth and yield

    OpenAIRE

    Rodo Angélica B.; Marcos-Filho Julio

    2003-01-01

    Research has emphasized the relationship of laboratory germination and vigor to seedling emergence and stand establishment, but information relating seed vigor to plant performance is less available. The reliable procedures to evaluate onion (Allium cepa L.) seed vigor and decided the differences between seed physiological potential influence plant performance in field conditions were identified in two experimental years. Six seed lots of Petroline cultivar were evaluated for germination and ...

  20. Physical Constraints to Aquatic Plant Growth in New Zealand Lakes

    OpenAIRE

    Hawes, Ian; Riis, T.; Sutherland, D.; Flanagan, M.

    2003-01-01

    The nature of aquatic plant communities often defines benthic habitat within oligotrophic and mesotrophic lakes and lake management increasingly recognizes the importance of maintaining plant diversity in order to sustain biological diversity and capacity within lakes. We have developed simple statistical relationships between key physical and vegetation variables that define the habitat requirements, or “habitat-templates”, of key vegetation types to facilitate managemen...

  1. A plant plasma membrane Ca2+ pump is required for normal pollen tube growth and fertilization

    DEFF Research Database (Denmark)

    Schiøtt, Morten; Romanowsky, Shawn M; Bækgaard, Lone

    2004-01-01

    Ca(2+) signals are thought to play important roles in plant growth and development, including key aspects of pollen tube growth and fertilization. The dynamics of a Ca(2+) signal are largely controlled by influx (through channels) and efflux (through pumps and antiporters). The Arabidopsis genome...... and a high frequency of aborted fertilization, resulting in a >80% reduction in seed set. These findings identify a plasma membrane Ca(2+) transporter as a key regulator of pollen development and fertilization in flowering plants....

  2. Effect of Pesticides on Growth or Rhizobia and Their Host Plants During Symbiosis

    Institute of Scientific and Technical Information of China (English)

    B.Madhavi; C.S.ANAND; 等

    1993-01-01

    Effect of various pesticides(insecticides,fungicides and herbicides)has been studied on growth and efficiency of symbiotic properties of 3 fast growing Rhizobuium sp.under green house conditions.The results reveales adverse effects on plant growth and nitrogen fixing capactity as measured by dry weight and totoal nitrogen content of plants infected with pesticide treated Rhizobium.Of the pesticides terbicides were found to be more effective on the above parameters than the insecticides and fungicides.

  3. Production of Plant Growth-Regulating Substances by the Vesicular-Arbuscular Mycorrhizal Fungus Glomus mosseae

    OpenAIRE

    Barea, José M.; Azcón-Aguilar, Concepción

    1982-01-01

    Glomus mosseae, a representative species of Endogonaceae (Phycomycetes) able to form vesicular-arbuscular mycorrhiza, was investigated for phytohormone production. Spores of G. mosseae were axenically germinated in water, and the resultant mycelial growth was assayed by standard procedures for extracting plant hormones from microbial cultures. Paper partition chromatography and specific bioassays were used to separate and identify plant growth-regulating substances. The microorganism synthesi...

  4. Functional genomics analysis of plant growth-promoting rhizobacterial traits involved in rhizosphere competence

    OpenAIRE

    Barret, Matthieu; Morrissey, John P.; O’Gara, Fergal

    2011-01-01

    In soil, some specific bacterial populations, called plant growth-promoting rhizobacteria are able to promote plant growth and/or reduce the incidence of soil-borne diseases. Rhizosphere competence is an important prerequisite for the efficacy of these biocontrol strains. Therefore, over decades, multiple approaches have been combined to understand the molecular basis of bacterial traits involved in rhizosphere competence. This review addresses the bacterial genes expressed during bacterial–p...

  5. Complete genome of Planococcus rifietoensis M8(T), a halotolerant and potentially plant growth promoting bacterium.

    Science.gov (United States)

    See-Too, Wah-Seng; Convey, Peter; Pearce, David A; Lim, Yan Lue; Ee, Robson; Yin, Wai-Fong; Chan, Kok-Gan

    2016-03-10

    Planococcus rifietoensis M8(T) (=DSM 15069(T)=ATCC BAA-790(T)) is a halotolerant bacterium with potential plant growth promoting properties isolated from an algal mat collected from a sulfurous spring in Campania (Italy). This paper presents the first complete genome of P. rifietoensis M8(T). Genes coding for various potentially plant growth promoting properties were identified within its genome. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Pre-sowing magnetic treatments of tomato seeds increase the growth and yield of plants.

    Science.gov (United States)

    De Souza, A; Garcí, D; Sueiro, L; Gilart, F; Porras, E; Licea, L

    2006-05-01

    The effects of pre-sowing magnetic treatments on growth and yield of tomato (cv Campbell-28) were investigated under field conditions. Tomato seeds were exposed to full-wave rectified sinusoidal non-uniform magnetic fields (MFs) induced by an electromagnet at 100 mT (rms) for 10 min and at 170 mT (rms) for 3 min. Non-treated seeds were considered as controls. Plants were grown in experimental plots (30.2 m(2)) and were cultivated according to standard agricultural practices. During the vegetative and generative growth stages, samples were collected at regular intervals for growth rate analyses, and the resistance of plants to geminivirus and early blight was evaluated. At physiological maturity, the plants were harvested from each plot and the yield and yield parameters were determined. In the vegetative stage, the treatments led to a significant increase in leaf area, leaf dry weight, and specific leaf area (SLA) per plant. Also, the leaf, stem, and root relative growth rates of plants derived from magnetically treated seeds were greater than those shown by the control plants. In the generative stage, leaf area per plant and relative growth rates of fruits from plants from magnetically exposed seeds were greater than those of the control plant fruits. At fruit maturity stage, all magnetic treatments increased significantly (P magnetically treated seeds than that of the controls. A significant delay in the appearance of first symptoms of geminivirus and early blight and a reduced infection rate of early blight were observed in the plants from exposed seeds to MFs. Pre-sowing magnetic treatments would enhance the growth and yield of tomato crop.

  7. Effect of Plant Growth Regulators on Phytoremediation of Hexachlorocyclohexane-Contaminated Soil.

    Science.gov (United States)

    Chouychai, Waraporn; Kruatrachue, Maleeya; Lee, Hung

    2015-01-01

    The influence of three plant growth regulators, indolebutyric acid (IBA), thidiazuron (TDZ) and gibberellic acid (GA3), either individually or in pair-wise combinations, on the ability of waxy corn plant to remove hexachlorocyclohexane (HCH) from contaminated soil was studied. Waxy corn seeds were immersed for 3 h in solutions of 1.0 mg/l IBA, 0.01 mg/l TDZ, 0.1 mg/l GA3, or a mixture of two of the growth regulators, and then inoculated in soil contaminated with 46.8 mg/kg HCH for 30 days. Pretreatment of corn seeds with the plant growth regulators did not enhance corn growth when compared with those immersed in distilled water (control), but the pretreatment enhanced HCH removal significantly. On day 30, HCH concentration in the bulk soil planted with corn seeds pretreated with GA3 or TDZ+GA3 decreased by 97.4% and 98.4%, respectively. In comparison, HCH removal in soil planted with non-pretreated control waxy corn seeds was only 35.7%. The effect of several growth regulator application methods was tested with 0.01 mg/l TDZ. The results showed that none of the methods, which ranged from seed immersion, watering in soil, or spraying on shoots, affected HCH removal from soil. However, the method of applying the growth regulators may affect corn growth. Watering the corn plant with TDZ in soil led to higher root fresh weight (2.2 g) and higher root dried weight (0.57 g) than the other treatments (0.2-1.7 g root fresh weight and 0.02-0.43 g root dried weight) on day 30. Varying the concentrations of GA3 did not affect the enhancement of corn growth and HCH removal on day 30. The results showed that plant growth regulators may have potential for use to enhance HCH phytoremediation.

  8. Grain Diversity Effects on Banker Plant Growth and Parasitism by Aphidius colemani

    Directory of Open Access Journals (Sweden)

    Travis McClure

    2015-09-01

    Full Text Available Green peach aphid (Myzus persicae Sulzer (Hemiptera: Aphididae is a serious greenhouse pest with a short generation time, parthenogenetic reproduction and a broad host range. Banker plant systems are becoming a more common form of biological control for this pest. This system consists of grain “banker plants” infested with R. padi, an alternative hosts for the parasitoid Aphidius colemani. Thus A. colemani can reproduce on the banker plant when M. persicae populations are low. This system can increase pest suppression; however, like other biological control tools, efficacy is inconsistent. One reason is because several different grain species have been used. Our studies determined if there were benefits to planting interspecific mixture banker plants, similar to when open agricultural systems use mixed cropping. Our study found that although banker plants grow larger when planted as mixtures this added plant growth does not increase in the number of aphids, or mummies an individual banker plant can sustain. Rye banker plants grew larger, and sustained more mummies than the other species we tested, but barley banker plants resulted in a similar number of aphids in a more condensed area. Ultimately, we did not see any differences in pest suppression between monoculture banker plants, mixture banker plants, or our augmentative release treatment. However, using banker plants resulted in more female parasitoids than the augmentative release, a benefit to using banker plant systems.

  9. Anatomical, morphological, and phytochemical effects of inoculation with plant growth- promoting rhizobacteria on peppermint (Mentha piperita).

    Science.gov (United States)

    del Rosario Cappellari, Lorena; Santoro, Maricel Valeria; Reinoso, Herminda; Travaglia, Claudia; Giordano, Walter; Banchio, Erika

    2015-02-01

    Plant growth-promoting rhizobacteria (PGPR) generally exert their effects through enhancement of plant nutrient status and/or phytohormone production. The effects of PGPR on aromatic plant species are poorly known. We measured plant growth parameters, chlorophyll content, trichome density, stomatal density, and levels of secondary metabolites in peppermint (Mentha piperita) seedlings inoculated with PGPR strains Bacillus subtilis GB03, Pseudomonas fluorescens WCS417r, P. putida SJ04, or a combination of WCS417r + SJ04. The treated plants, in comparison with controls, showed increases in shoot biomass, root biomass, leaf area, node number, trichome density, and stomatal density, and marked qualitative and quantitative changes in monoterpene content. Improved knowledge of the factors that control or affect biosynthesis of secondary metabolites and monoterpene accumulation will lead to strategies for improved cultivation and productivity of aromatic plants and other agricultural crops without the use of chemical fertilizers or pesticides.

  10. 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.

  11. 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.

  12. Plant-feeding nematodes in coastal sand dunes: occurrence, host specificity and effects on plant growth

    NARCIS (Netherlands)

    Brinkman, E.P.; Duyts, H.; Karssen, G.; Stoel, C.D.; Putten, van der W.H.

    2015-01-01

    Aims Coastal sand dunes have a well-established abiotic gradient from beach to land and a corresponding spatial gradient of plant species representing succession in time. Here, we relate the distribution of plant-feeding nematodes with dominant plant species in the field to host specialization and

  13. 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)

  14. 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.

  15. Plant AGC protein kinases orient auxin-mediated differential growth and organogenesis

    NARCIS (Netherlands)

    Galván Ampudia, Carlos Samuel

    2009-01-01

    In view of their predominant sessile lifestyle, plants need to be able to adapt to changes in their environment. Environmental signals such as light and gravity modulate plant growth and architecture by redirecting polar cell-to-cell transport of auxin, thus causing changes in the distribution of th

  16. Improvement of growth rate of plants by bubble discharge in water

    Science.gov (United States)

    Takahata, Junichiro; Takaki, Koichi; Satta, Naoya; Takahashi, Katsuyuki; Fujio, Takuya; Sasaki, Yuji

    2015-01-01

    The effect of bubble discharge in water on the growth rate of plants was investigated experimentally for application to plant cultivation systems. Spinach (Spinacia oleracea), radish (Raphanus sativus var. sativus), and strawberry (Fragaria × ananassa) were used as specimens to clarify the effect of the discharge treatment on edible parts of the plants. The specimens were cultivated in pots filled with artificial soil, which included chicken manure charcoal. Distilled water was sprayed on the artificial soil and drained through a hole in the pots to a water storage tank. The water was circulated from the water storage tank to the cultivation pots after 15 or 30 min discharge treatment on alternate days. A magnetic compression-type pulsed power generator was used to produce the bubble discharge with a repetition rate of 250 pps. The plant height in the growth phase and the dry weight of the harvested plants were improved markedly by the discharge treatment in water. The soil and plant analyzer development (SPAD) value of the plants also improved in the growth phase of the plants. The concentration of nitrate nitrogen, which mainly contributed to the improvement of the growth rate, in the water increased with the discharge treatment. The Brix value of edible parts of Fragaria × ananassa increased with the discharge treatment. The inactivation of bacteria in the water was also confirmed with the discharge treatment.

  17. Efficiency of plant growth promoting rhizobacteria isolated from sand dunes of Chennai coastal area.

    Science.gov (United States)

    Muthezhilan, R; Sindhuja, B S; Hussain, A Jaffar; Jayaprakashvel, M

    2012-08-15

    Plant Growth Promoting Rhizobacteria (PGPR) are beneficial bacteria that colonize the plant root and enhance the plant growth. The use of PGPR is steadily increasing in agriculture and offers an attractive way to replace chemical fertilizers, pesticides and supplements. In the present study, PGPR were isolated from 18 different rhizosphere soil samples of coastal sand dune plants, belonging to the genus Ipomoea sp. collected from the Chennai coastal area. For isolation of bacteria from soil samples, pour plate technique was followed. The rhizobacterial population was ranged from 4.4 x 10(6)-7.5 x 10(7) CFU g(-1). From that, 46 morphologically different bacterial strains were isolated. Among 46, 18 strains exhibited the production of Indole Acetic Acid. (IAA). When screened for phosphate solubilzing activity, six strains showed maximum activity. All these selected six strains were screened for seed germination among which these two strains (AMET1136 and AMET 1148) showed remarkable increase in the seed germination of black gram and green gram. For plant growth promotion, three types of treatments namely, seed bacterization, soil drenching and mixed (seed+soil) were carried out to check the potential of these two strains. Among that one strain which was identified as Pseudomonas sp. AMET1148 showed remarkable and significant increase in shoot length and root length of the tested plants. The study concluded that PGPR from coastal sand dund plants can be developed as plant growth promoters in agricultural crops.

  18. Influence of calcium foliar fertilization on plant growth, nutrient concentrations, and fruit quality of papaya.

    Science.gov (United States)

    Calcium (Ca) is a major plant nutrient that affects cell wall and plasma membrane formation and plays a key role in plant growth and biomass production. It can be used to decrease fruit decay and increase firmness and shelf life. So far, little attention has been paid to investigate the effects of f...

  19. Effects of plant-soil feedback on tree seedling growth under arid conditions

    NARCIS (Netherlands)

    Meijer, S.S.; Holmgren, M.; Putten, van der W.H.

    2011-01-01

    Aims: Plants are able to influence their growing environment by changing biotic and abiotic soil conditions. These soil conditions in turn can influence plant growth conditions, which is called plant–soil feedback. Plant–soil feedback is known to be operative in a wide variety of ecosystems ranging

  20. 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

  1. Assessment of cannabinoids content in micropropagated plants of Cannabis sativa and their comparison with conventionally propagated plants and mother plant during developmental stages of growth.

    Science.gov (United States)

    Chandra, Suman; Lata, Hemant; Mehmedic, Zlatko; Khan, Ikhlas A; ElSohly, Mahmoud A

    2010-05-01

    Gas chromatography-flame ionization detection (GC-FID) was used to assess the chemical profile and quantification of cannabinoids to identify the differences, if existing, in the chemical constituents of in vitro propagated plants (IVP), conventionally grown plants (VP) and indoor grown mother plants (MP-Indoor) of a high THC yielding variety of Cannabis sativa L. during different developmental stages of growth. In general, THC content in all groups increased with plant age up to a highest level during the budding stage where the THC content reached a plateau before the onset of senescence. The pattern of changes observed in the concentration of other cannabinoids content with plants age has followed a similar trend in all groups of plants. Qualitatively, cannabinoids profiles obtained using GC-FID, in MP-indoor, VP and IVP plants were found to be similar to each other and to that of the field grown mother plant (MP field) of C. sativa. Minor differences observed in cannabinoids concentration within and among the groups were not found to be statistically significant. Our results confirm the clonal fidelity of IVP plants of C. sativa and suggest that the biochemical mechanism used in this study to produce the micropropagated plants does not affect the metabolic content and can be used for the mass propagation of true to type plants of this species for commercial pharmaceutical use.

  2. Pig manure vermicompost as a component of a horticultural bedding plant medium: effects on physicochemical properties and plant growth.

    Science.gov (United States)

    Atiyeh, R M; Edwards, C A; Subler, S; Metzger, J D

    2001-05-01

    This experiment was designed to characterize the physical, chemical and microbial properties of a standard commercial horticultural, greenhouse container, bedding plant medium (Metro-Mix 360), that had been substituted with a range of increasing concentrations (0%, 5%, 10%, 25%, 50% and 100% by volume) of pig manure vermicompost and to relate these properties to plant growth responses. The growth trials used tomatoes (Lycopersicon esculentum Mill.), grown in the substituted media for 31 days under glasshouse conditions, with seedling growth recorded in 20 pots for each treatment. Half of the tomato seedlings (10 pots per treatment) were watered daily with liquid inorganic fertilizer while the other half received water only. The percentage total porosity, percentage air space, pH and ammonium concentrations of the container medium all decreased significantly, after substitution of Metro-Mix 360 with equivalent amounts of pig manure vermicompost; whereas bulk density, container capacity, electrical conductivity, overall microbial activity and nitrate concentrations, all increased with increasing substitutions of vermicompost. The growth of tomato seedlings in the potting mixtures containing 100% pig manure vermicompost was reduced, possibly as a result of high soluble salt concentrations in the vermicompost and poorer porosity and aeration. The growth of tomato seedlings was greatest after substitution of Metro-Mix 360 with between 25% and 50% pig manure vermicompost, with more growth occurring in combinations of pig manure vermicompost treated regularly with a liquid fertilizer solution than in those with no fertilizer applied. Some of the growth enhancement in these mixtures seemed to be related to the combined effects of improved porosity, aeration and water retention in the medium and the high nitrate content of the substrate, which produced an increased uptake of nitrogen by the plant tissues, resulting in increased plant growth. When the tomato seedlings were

  3. Stimulation of methane oxidation potential and effects on vegetation growth by bottom ash addition in a landfill final evapotranspiration cover.

    Science.gov (United States)

    Kim, Gil Won; Ho, Adrian; Kim, Pil Joo; Kim, Sang Yoon

    2016-09-01

    The landfilling of municipal solid waste is a significant source of atmospheric methane (CH4), contributing up to 20% of total anthropogenic CH4 emissions. The evapotranspiration (ET) cover system, an alternative final cover system in waste landfills, has been considered to be a promising way to mitigate CH4 emissions, as well as to prevent water infiltration using vegetation on landfill cover soils. In our previous studies, bottom ash from coal-fired power plants was selected among several industrial residues (blast furnace slag, bottom ash, construction waste, steel manufacture slag, stone powder sludge, and waste gypsum) as the best additive for ET cover systems, with the highest mechanical performance achieved for a 35% (wtwt(-1)) bottom ash content in soil. In this study, to evaluate the field applicability of bottom ash mixed soil as ET cover, four sets of lysimeters (height 1.2m×width 2m×length 6m) were constructed in 2007, and four different treatments were installed: (i) soil+bottom ash (35% wtwt(-1)) (SB); (ii) soil+compost (2% wtwt(-1), approximately corresponding to 40Mgha(-1) in arable field scale) (SC); (iii) soil+bottom ash+compost (SBC); and (iv) soil only as the control (S). The effects of bottom ash mixing in ET cover soil on CH4 oxidation potential and vegetation growth were evaluated in a pilot ET cover system in the 5th year after installation by pilot experiments using the treatments. Our results showed that soil properties were significantly improved by bottom ash mixing, resulting in higher plant growth. Bottom ash addition significantly increased the CH4 oxidation potential of the ET cover soil, mainly due to improved organic matter and available copper concentration, enhancing methanotrophic abundances in soil amended with bottom ash. Conclusively, bottom ash could be a good alternative as a soil additive in the ET cover system to improve vegetation growth and mitigate CH4 emission impact in the waste landfill system. Copyright © 2016

  4. Growth and conversion of solar energy of grafted tomato plants under protected cultivation

    Directory of Open Access Journals (Sweden)

    Tiago Pedó

    2015-07-01

    Full Text Available The grafting technique favors cultivation tomato under conditions environment adverse, being the effects on the physiology of scarce plants. Thus, this study aimed to evaluate the growth and solar energy conversion efficiency in grafted tomato and not grafted in greenhouse. The grafting was performed by grafting of cleft and the treatments consisted of tomato plants grafted on hybrid Kaguemusha® and not grafted. The samples for growth analysis were performed at intervals of fourteen days after transplanting (DAT by the end of the crop cycle. At each harvest, plants were separated into organs, being determined to total dry matter (Wt, rates of dry matter production (Ct and relative growth (Rw, net assimilation (Ea, leaf area index (L, growth rate, leaf area (Ca, relative growth of leaf area (Ra, leaf area ratio (Fa, leaf weight (Fw, specific leaf area (Sa, conversion efficiency solar energy (? and assimilation rate of fruit (Efr. From the analysis of data growth, the plants grafted on the hybrid Kaguemusha® had higher Wt, Ct, Rw, Ea and ? compared to non-grafted that showed a high Fa and Fw. Therefore, the stress caused by grafting did not affect the growth at the end of the development cycle of tomato plants, being important feature to keep the crop yield

  5. Effect of plant growth regulators and nitrogenous compounds on ...

    African Journals Online (AJOL)

    PROF HORSFALL

    One of the problems that farmers face is the germination of ... which is used in modern medicine as a circulatory stimulant ... growth regulators and biostimulants solutions can .... enzymes involved in gluconeogenesis, and the process of seed ...

  6. 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.

  7. Lactococcus lactis metabolism and gene expression during growth on plant tissues.

    Science.gov (United States)

    Golomb, Benjamin L; Marco, Maria L

    2015-01-01

    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.

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

    Science.gov (United States)

    De La Torre-Ruiz, Neyser; Ruiz-Valdiviezo, Víctor Manuel; Rincón-Molina, Clara Ivette; Rodríguez-Mendiola, Martha; Arias-Castro, Carlos; Gutiérrez-Miceli, Federico Antonio; Palomeque-Dominguez, Héctor; Rincón-Rosales, Reiner

    2016-01-01

    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 (pagave plants with proper biological characteristics for agroindustrial and biotechnological use and to increase the sugar content in this agave species. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  9. Effects of biogas digestate on soil properties and plant growth

    Science.gov (United States)

    Gulyás, Miklós; Füleky, György

    2013-04-01

    Farming methods and food industries generate large amounts manure and other useful raw materials that need safe disposal. Following the international trends great numbers of biogas plants were opened during the last few years in Hungary. However this issue presents a number of new questions, including the subsequent use of anaerobic fermentation residues. So far we have only limited information about it's agricultural applications. Farmers and authorities are very skeptic because feedstocks are very different so the endproduct will be different, too. However, this endproduct can be applied as fertilizer. The aim of our work is to determine the effects of this product in plant-soil system. Digestate contains high amount of nitrogen which is present mainly ammonium form and this form can cause root depression and lower germination rates. Pot experiments were established with different rates of nitrogen content (80 kg ha-1N, 120 kg ha-1N, 170 kg ha-1N, and control). Maximum rates were determine by the Nitrate Directive. Soil moisture was 60% of maximum of water capacity. Digestate and distilled water were homogenized and added to 200g loamy soil. Rye-grass (Lolium perenne) was applied as a test plant. Treatments were randomized design and 10 replications. Three pot from each treatment were used to observe the germination and progress of plants. We investigated the effect of the digestate on nitrate- and ammonium-ion content of soil. The amount of nitrate- and ammonium-N of soil was determine with distillation. The ammonium-N levels increased with the doses on the first day but on the sixth-seventh day this amount totally falled down, because NH4-N transformed to NO3-N. Nitrate level increased continuously untill the tenth day, later decreased as the result of the plant and microbes consumption. The increasing doses inhibited the germination and root development of the plants. We experienced fewer roots, which were different form control.

  10. Analysis of genes contributing to plant-beneficial functions in Plant Growth-Promoting Rhizobacteria and related Proteobacteria.

    Science.gov (United States)

    Bruto, Maxime; Prigent-Combaret, Claire; Muller, Daniel; Moënne-Loccoz, Yvan

    2014-09-02

    The positive effects of root-colonizing bacteria cooperating with plants lead to improved growth and/or health of their eukaryotic hosts. Some of these Plant Growth-Promoting Rhizobacteria (PGPR) display several plant-beneficial properties, suggesting that the accumulation of the corresponding genes could have been selected in these bacteria. Here, this issue was targeted using 23 genes contributing directly or indirectly to established PGPR effects, based on genome sequence analysis of 304 contrasted Alpha- Beta- and Gammaproteobacteria. Most of the 23 genes studied were also found in non-PGPR Proteobacteria and none of them were common to all 25 PGPR genomes studied. However, ancestral character reconstruction indicated that gene transfers -predominantly ancient- resulted in characteristic gene combinations according to taxonomic subgroups of PGPR strains. This suggests that the PGPR-plant cooperation could have established separately in various taxa, yielding PGPR strains that use different gene assortments. The number of genes contributing to plant-beneficial functions increased along the continuum -animal pathogens, phytopathogens, saprophytes, endophytes/symbionts, PGPR- indicating that the accumulation of these genes (and possibly of different plant-beneficial traits) might be an intrinsic PGPR feature. This work uncovered preferential associations occurring between certain genes contributing to phytobeneficial traits and provides new insights into the emergence of PGPR bacteria.

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

    Science.gov (United States)

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

    2016-04-01

    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. Here, we performed a genome-wide association (GWA) study on natural genetic variation in Arabidopsis for the ability to profit from rhizobacteria-mediated plant growth-promotion. To this end, 302 Arabidopsis accessions were tested for root architecture characteristics and shoot fresh weight in response to exposure to WCS417r. Although virtually all Arabidopsis accessions tested responded positively to WCS417r, there was a large variation between accessions in the increase in shoot fresh weight, the extra number of lateral roots formed, and the effect on primary root length. Correlation analyses revealed that the bacterially-mediated increase in shoot fresh weight is related to alterations in root architecture. GWA mapping for WCS417r-stimulated changes in root and shoot growth characteristics revealed 10 genetic loci highly associated with the responsiveness of Arabidopsis to the plant growth-promoting activity of WCS417r. Several of the underlying candidate genes have been implicated in important plant growth-related processes. These results demonstrate that plants possess natural genetic variation for the capacity to profit from the plant growth-promoting function of a beneficial rhizobacterium in their rhizosphere. This knowledge is a promising starting point for sustainable breeding strategies for future crops that are better able to maximize profitable functions from their root microbiome.

  12. Inhibition of bacterial, fungal and plant growth by testa extracts of Citrullus genotypes

    Science.gov (United States)

    Watermelon (Citrullus lanatus var. lanatus (Thunb.) Matsum & Nakai) seed exudates inhibit germination and seedling growth of several plant species and growth of pathogenic fungi and bacteria. This study was conducted to determine if extractable components in testae contribute to the inhibition. T...

  13. Genome Sequences of Two Plant Growth-Promoting Fluorescent Pseudomonas Strains, R62 and R81

    OpenAIRE

    Mathimaran, N.; Srivastava, R.; Wiemken, A; A.K. Sharma; Boller, T.

    2012-01-01

    Plant growth-promoting rhizobacterial (PGPR) strains R62 and R81 have previously been isolated and characterized as part of the Indo-Swiss Collaboration in Biotechnology. Here we present the draft genome sequences of these two PGPR strains, with the aim of unraveling the mechanisms behind their ability to promote wheat growth.

  14. Genome sequences of two plant growth-promoting fluorescent Pseudomonas strains, R62 and R81.

    Science.gov (United States)

    Mathimaran, N; Srivastava, R; Wiemken, A; Sharma, A K; Boller, T

    2012-06-01

    Plant growth-promoting rhizobacterial (PGPR) strains R62 and R81 have previously been isolated and characterized as part of the Indo-Swiss Collaboration in Biotechnology. Here we present the draft genome sequences of these two PGPR strains, with the aim of unraveling the mechanisms behind their ability to promote wheat growth.

  15. Ten-Year Growth of Five Planted Hardwood Species Mechanical Weed Control on Sharkey Clay Soil

    Science.gov (United States)

    Roger M. Krinard; Harvey E. Kennedy

    1983-01-01

    Five hardwood species planted on Sharkey clay soil showed little practical difference in growth whether plots were mowed or diskedfor weed control in years 6 to 10, although disking had given better growth in the first 5 years. After 10 years, cottonwood (Populus deltoides Bartr. ex Marsh.) stem volume was at least three times greater than other species. Changes in...

  16. 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...

  17. Antibacterial activity of alimentary plants against Staphylococcus aureus growth.

    Science.gov (United States)

    Pérez, C; Anesini, C

    1994-01-01

    Alimentary plants were screened for antibacterial activity against a penicillin G resistant strain of Staphylococcus aureus. Twenty-five samples of plant material corresponding to 21 species from 13 families were used. Both aqueous and ethanol extracts were obtained from them. Antibacterial activity was determined by the agar-well diffusion method, using cephazolin as a standard antibiotic. Seventeen ethanol extracts were found active. Eugenia caryophyllata (clavo de olor*) flowers, Myristica fragans (nuez moscada*) seeds, Theobroma cacao (cacao*) seed bark, Triticum sp (trigo*) fruit, Zea mays (maíz*) fruit and Piper nigrum (pimienta*) ripe fruit produced some of the more active extracts (* = Argentine vulgar names).

  18. Pollination syndromes in a Caatinga plant community in northeastern Brazil: seasonal availability of floral resources in different plant growth habits

    Directory of Open Access Journals (Sweden)

    ZGM Quirino

    Full Text Available To describe plant phenological patterns and correlate functioning for the quantity and quality of resources available for the pollinator, it is crucial to understand the temporal dynamics of biological communities. In this way, the pollination syndromes of 46 species with different growth habits (trees, shrubs, herbs, and vines were examined in an area of Caatinga vegetation, northeastern Brazil (7° 28′ 45″ S and 36° 54′ 18″ W, during two years. Flowering was monitored monthly in all the species, over two years (from January 2003 to December 2004. Pollination syndromes were characterised based on floral traits such as size, colour, morphology, symmetry, floral resources, as well as on direct visual observation of floral visitors on focal plants and published information. We observed differences among the plant growth habits with respect to floral traits, types of resources offered, and floral syndromes. The flowering periods of the species varied among floral syndrome groups. The majority of the melittophilous species flowered during the rainy season in the two study years, while the species of the other pollination syndroms flowered at the end of the dry season. An asynchrony of flowering was noted among the chiropterophilous species, while the phalenophilous group concentrated during the rainy season. The overall availability of floral resources was different during the rainy and the dry seasons, and also it varied among plants with different growth habits. The availability of oil-flowers coincided with the period of low nectar availability. We observed a relationship between the temporal distribution of the pollination syndromes and the availability of floral resources among each growth habits in this tropical ecosystem. Resource allocation in seasonal environments, such as the Caatinga, can function as a strategy for maintaining pollinators, facilitating therefore the reproductive success of plant species. The availability of

  19. Pollination syndromes in a Caatinga plant community in northeastern Brazil: seasonal availability of floral resources in different plant growth habits.

    Science.gov (United States)

    Quirino, Z G M; Machado, I C

    2014-02-01

    To describe plant phenological patterns and correlate functioning for the quantity and quality of resources available for the pollinator, it is crucial to understand the temporal dynamics of biological communities. In this way, the pollination syndromes of 46 species with different growth habits (trees, shrubs, herbs, and vines) were examined in an area of Caatinga vegetation, northeastern Brazil (7° 28' 45″ S and 36° 54' 18″ W), during two years. Flowering was monitored monthly in all the species, over two years (from January 2003 to December 2004). Pollination syndromes were characterised based on floral traits such as size, colour, morphology, symmetry, floral resources, as well as on direct visual observation of floral visitors on focal plants and published information. We observed differences among the plant growth habits with respect to floral traits, types of resources offered, and floral syndromes. The flowering periods of the species varied among floral syndrome groups. The majority of the melittophilous species flowered during the rainy season in the two study years, while the species of the other pollination syndroms flowered at the end of the dry season. An asynchrony of flowering was noted among the chiropterophilous species, while the phalenophilous group concentrated during the rainy season. The overall availability of floral resources was different during the rainy and the dry seasons, and also it varied among plants with different growth habits. The availability of oil-flowers coincided with the period of low nectar availability. We observed a relationship between the temporal distribution of the pollination syndromes and the availability of floral resources among each growth habits in this tropical ecosystem. Resource allocation in seasonal environments, such as the Caatinga, can function as a strategy for maintaining pollinators, facilitating therefore the reproductive success of plant species. The availability of floral resources during

  20. Response to long-term growth hormone therapy in patients affected by RASopathies and growth hormone deficiency: Patterns of growth, puberty and final height data.

    Science.gov (United States)

    Tamburrino, Federica; Gibertoni, Dino; Rossi, Cesare; Scarano, Emanuela; Perri, Annamaria; Montanari, Francesca; Fantini, Maria Pia; Pession, Andrea; Tartaglia, Marco; Mazzanti, Laura

    2015-11-01

    RASopathies are developmental disorders caused by heterozygous germline mutations in genes encoding proteins in the RAS-MAPK signaling pathway. Reduced growth is a common feature. Several studies generated data on growth, final height (FH), and height velocity (HV) after growth hormone (GH) treatment in patients with these disorders, particularly in Noonan syndrome, the most common RASopathy. These studies, however, refer to heterogeneous cohorts in terms of molecular information, GH status, age at start and length of therapy, and GH dosage. This work reports growth data in 88 patients affected by RASopathies with molecularly confirmed diagnosis, together with statistics on body proportions, pubertal pattern, and FH in 33, including 16 treated with GH therapy for proven GH deficiency. Thirty-three patients showed GH deficiency after pharmacological tests, and were GH-treated for an average period of 6.8 ± 4.8 years. Before starting therapy, HV was -2.6 ± 1.3 SDS, and mean basal IGF1 levels were -2.0 ± 1.1 SDS. Long-term GH therapy, starting early during childhood, resulted in a positive height response compared with untreated patients (1.3 SDS in terms of height-gain), normalizing FH for Ranke standards but not for general population and Target Height. Pubertal timing negatively affected pubertal growth spurt and FH, with IGF1 standardized score increased from -2.43 to -0.27 SDS. During GH treatment, no significant change in bone age velocity, body proportions, or cardiovascular function was observed.

  1. Plant Growth-Promoting Rhizobacteria Inoculation to Enhance Vegetative Growth, Nitrogen Fixation and Nitrogen Remobilisation of Maize under Greenhouse Conditions.

    Directory of Open Access Journals (Sweden)

    Khing Boon Kuan

    Full Text Available Plant growth-promoting rhizobacteria (PGPR may provide a biological alternative to fix atmospheric N2 and delay N remobilisation in maize plant to increase crop yield, based on an understanding that plant-N remobilisation is directly correlated to its plant senescence. Thus, four PGPR strains were selected from a series of bacterial strains isolated from maize roots at two locations in Malaysia. The PGPR strains were screened in vitro for their biochemical plant growth-promoting (PGP abilities and plant growth promotion assays. These strains were identified as Klebsiella sp. Br1, Klebsiella pneumoniae Fr1, Bacillus pumilus S1r1 and Acinetobacter sp. S3r2 and a reference strain used was Bacillus subtilis UPMB10. All the PGPR strains were tested positive for N2 fixation, phosphate solubilisation and auxin production by in vitro tests. In a greenhouse experiment with reduced fertiliser-N input (a third of recommended fertiliser-N rate, the N2 fixation abilities of PGPR in association with maize were determined by 15N isotope dilution technique at two harvests, namely, prior to anthesis (D50 and ear harvest (D65. The results indicated that dry biomass of top, root and ear, total N content and bacterial colonisations in non-rhizosphere, rhizosphere and endosphere of maize roots were influenced by PGPR inoculation. In particular, the plants inoculated with B. pumilus S1r1 generally outperformed those with the other treatments. They produced the highest N2 fixing capacity of 30.5% (262 mg N2 fixed plant-1 and 25.5% (304 mg N2 fixed plant-1 of the total N requirement of maize top at D50 and D65, respectively. N remobilisation and plant senescence in maize were delayed by PGPR inoculation, which is an indicative of greater grain production. This is indicated by significant interactions between PGPR strains and time of harvests for parameters on N uptake and at. % 15Ne of tassel. The phenomenon is also supported by the lower N content in tassels of maize

  2. Plant Growth-Promoting Rhizobacteria Inoculation to Enhance Vegetative Growth, Nitrogen Fixation and Nitrogen Remobilisation of Maize under Greenhouse Conditions.

    Science.gov (United States)

    Kuan, Khing Boon; Othman, Radziah; Abdul Rahim, Khairuddin; Shamsuddin, Zulkifli H

    2016-01-01

    Plant growth-promoting rhizobacteria (PGPR) may provide a biological alternative to fix atmospheric N2 and delay N remobilisation in maize plant to increase crop yield, based on an understanding that plant-N remobilisation is directly correlated to its plant senescence. Thus, four PGPR strains were selected from a series of bacterial strains isolated from maize roots at two locations in Malaysia. The PGPR strains were screened in vitro for their biochemical plant growth-promoting (PGP) abilities and plant growth promotion assays. These strains were identified as Klebsiella sp. Br1, Klebsiella pneumoniae Fr1, Bacillus pumilus S1r1 and Acinetobacter sp. S3r2 and a reference strain used was Bacillus subtilis UPMB10. All the PGPR strains were tested positive for N2 fixation, phosphate solubilisation and auxin production by in vitro tests. In a greenhouse experiment with reduced fertiliser-N input (a third of recommended fertiliser-N rate), the N2 fixation abilities of PGPR in association with maize were determined by 15N isotope dilution technique at two harvests, namely, prior to anthesis (D50) and ear harvest (D65). The results indicated that dry biomass of top, root and ear, total N content and bacterial colonisations in non-rhizosphere, rhizosphere and endosphere of maize roots were influenced by PGPR inoculation. In particular, the plants inoculated with B. pumilus S1r1 generally outperformed those with the other treatments. They produced the highest N2 fixing capacity of 30.5% (262 mg N2 fixed plant-1) and 25.5% (304 mg N2 fixed plant-1) of the total N requirement of maize top at D50 and D65, respectively. N remobilisation and plant senescence in maize were delayed by PGPR inoculation, which is an indicative of greater grain production. This is indicated by significant interactions between PGPR strains and time of harvests for parameters on N uptake and at. % 15Ne of tassel. The phenomenon is also supported by the lower N content in tassels of maize treated with

  3. District heating and cooling systems for communities through power plant retrofit and distribution networks. Phase 1: identificaion and assessment. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-09-01

    Appendix A, Utility Plant Characteristics, contains information describing the characteristics of seven utility plants that were considered during the final site selection process. The plants are: Valley Electric Generating Plant, downtown Milwaukee; Manitowoc Electric Generating Plant, downtown Manitowoc; Blount Street Electric Generating Plant, downtown Madison; Pulliam Electric Generating Plant, downtown Green Bay; Edgewater Electric Generating Plant, downtown Sheboygan; Rock River Electric Generating Plant, near Janesville and Beloit; and Black Hawk Electric Generating Plant, downtown Beloit. Additional appendices are: Future Loads; hvac Inventory; Load Calculations; Factors to Induce Potential Users; Turbine Retrofit/Distribution System Data; and Detailed Economic Analysis Results/Data.

  4. Development of the husk tomato plant (Physalis ixocarpa Brot.. III. Growth analysis

    Directory of Open Access Journals (Sweden)

    Francisco Cartujano-Escobar

    2014-01-01

    Full Text Available Growth analysis of husk tomato plants cv. Rendidora was done applying classical methods. Quantities such as the Relative Growth Rate, Leaf Area Ratio, Unit Leaf Rate and others were calculated in order to describe the changes which occur in the Physalis ixocarpa plant during its development from emergence to death. The mentioned quantities comported differently in the four periods of the life of husk tomato, providing a good insight into the changing direction and intensity of the main physiological processes and their mutual balance. It is believed that such recognition of the properties of a plant may help breeders.

  5. The influence of plant extracts on growth of Erwinia amylovora - the causal agent of fire blight

    Directory of Open Access Journals (Sweden)

    Grzegorz Krupiński

    2013-12-01

    Full Text Available Ethanol and water extracts obtained on Soxhlet apparatus from various organs and parts (leaves, flowers, shoots, onion, bark, fruit of 30 herbal and woody plants species were tested for growth inhibition of Erwinia amylovora using agar diffusion method. Active extracts were found in 23 plant species but in 13 ofthem it was found for the first time. The highest diameter of growth inhibition zone of this bacterium was caused by extracts from Aloe arborescens, Juglans regia, Rhus typhina, Salvia offici nalis and Satureja hortensis. In almost all cases ethanol appeared to be a better solvent of active plant substances against E.amylovora than water.

  6. Diverse Plant-Associated Pleosporalean Fungi from Saline Areas: Ecological Tolerance and Nitrogen-Status Dependent Effects on Plant Growth.

    Science.gov (United States)

    Qin, Yuan; Pan, Xueyu; Kubicek, Christian; Druzhinina, Irina; Chenthamara, Komal; Labbé, Jessy; Yuan, Zhilin

    2017-01-01

    Similar to mycorrhizal mutualists, the rhizospheric and endophytic fungi are also considered to act as active regulators of host fitness (e.g., nutrition and stress tolerance). Despite considerable work in selected model systems, it is generally poorly understood how plant-associated fungi are structured in habitats with extreme conditions and to what extent they contribute to improved plant performance. Here, we investigate the community composition of root and seed-associated fungi from six halophytes growing in saline areas of China, and found that the pleosporalean taxa (Ascomycota) were most frequently isolated across samples. A total of twenty-seven representative isolates were selected for construction of the phylogeny based on the multi-locus data (partial 18S rDNA, 28S rDNA, and transcription elongation factor 1-α), which classified them into seven families, one clade potentially representing a novel lineage. Fungal isolates were subjected to growth response assays by imposing temperature, pH, ionic and osmotic conditions. The fungi had a wide pH tolerance, while most isolates showed a variable degree of sensitivity to increasing concentration of either salt or sorbitol. Subsequent plant-fungal co-culture assays indicated that most isolates had only neutral or even adverse effects on plant growth in the presence of inorganic nitrogen. Interestingly, when provided with organic nitrogen sources the majority of the isolates enhanced plant growth especially aboveground biomass. Most of the fungi preferred organic nitrogen over its inorganic counterpart, suggesting that these fungi can readily mineralize organic nitrogen into inorganic nitrogen. Microscopy revealed that several isolates can successfully colonize roots and form melanized hyphae and/or microsclerotia-like structures within cortical cells suggesting a phylogenetic assignment as dark septate endophytes. This work provides a better understanding of the symbiotic relationship between plants and

  7. PREPARATION OF U-PLANT FOR FINAL DEMOLITION AND DISPOSAL - 12109E

    Energy Technology Data Exchange (ETDEWEB)

    FARABEE OA; HERZOG B; CAMERON C

    2012-02-16

    The U-Plant is one of the five major nuclear materials processing facilities at Hanford and was chosen as a pilot project to develop the modalities for closure of the other four facilities at Hanford and the rest of the Department of Energy (DOE) complex. The remedy for this facility was determined by a Record of Decision (ROD) pursuant to the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA). That remedy was to 'Close in Place - Partially Demolished Structure'. The U-Plant facility is identified as the 221-U Building and is a large, concrete structure nominally 247m (810 ft) long, 20 M (66 ft) wide and 24 m (77 ft) high with approximately 9 m (30 ft) being below grade level. It is a robust facility with walls ranging from 0.9 m to 2.7 m (3 ft to 9 ft) thick. One large room extends the entire length of the building that provides access to 40 sub-grade processing cells containing tanks, piping and other components. The work breakdown was divided into three major deliverables: (1) Tank D-10 Removal: removal of Tank D-10, which contained TRU waste; (2) Equipment Disposition: placement of contaminated equipment in the sub-grade cells; and (3) Canyon Grouting: grouting canyon void spaces to the maximum extent practical. A large number of pieces of contaminated equipment (pumps, piping, centrifuges, tanks, etc) from other facilities that had been stored on the canyon operating floor were placed inside of the sub-grade cells as final disposition, grouted and the cell shield plug reinstalled. This action precluded a large volume of waste being transported to another burial site. Finally, {approx}19,000 m3 ({approx}25,000 yd3) of grout was placed inside of the cells (in and around the contaminated equipment), in the major galleries. the ventilation tunnel, the external ventilation duct, and the hot pipe trench to minimize the potential for void spaces and to reduce the mobility, solubility, and/or toxicity of the grouted waste

  8. Lettuce growth and quality optimization in a plant factory

    NARCIS (Netherlands)

    Nicole, C.C.S.; Charalambous, F.; Martinakos, S.; De Voort, Van S.; Li, Z.; Verhoog, M.; Krijn, M.

    2016-01-01

    Since the early 2000s, plant factory (or vertical farm) technology has been introduced for growing vegetables and soft fruits. With a well-controlled environment, new health benefits, food safety, optimized nutrients and increased shelf-life can be offered to consumers. With the progress of light

  9. Influence of plant growth regulators on somatic embryos induction ...

    African Journals Online (AJOL)

    TANOH

    2013-04-17

    Apr 17, 2013 ... plants, the rubber-tree is generally considered to be recalcitrant with regard to somatic .... Fossard vitamins (Fossard, 1976) without choline chloride. MBm medium was fortified with different concentrations of 2,4-D (4.5 and.

  10. Endophytic bacteria with plant growth promoting and biocontrol abilities

    NARCIS (Netherlands)

    Malfanova, Natalia V.

    2013-01-01

    Since global food insecurity is one of the major problems faced by humanity, there is a necessity to increase plant productivity. For this, biofungicides and biofertilizers present an ecologically friendly alternative to their chemical counterparts. Among these bioinoculants, endophytic bacteria wit

  11. Endophytic bacteria with plant growth promoting and biocontrol abilities

    NARCIS (Netherlands)

    Malfanova, Natalia V.

    2013-01-01

    Since global food insecurity is one of the major problems faced by humanity, there is a necessity to increase plant productivity. For this, biofungicides and biofertilizers present an ecologically friendly alternative to their chemical counterparts. Among these bioinoculants, endophytic bacteria wit

  12. Effect of reduced light and low oxygen concentration on germination, growth and establishment of some plants

    DEFF Research Database (Denmark)

    Yasin, Muhammad

    Many abiotic factors effect plants germination, growth, and development. This Ph.D. study elucidates the effect of reduced light, low oxygen and seed dormancy on germination and growth of some weed species, field crops and vegetables. One study describes the growth and developmental responses of ...... improved the germination of the problematic invader Alliaria petiolate of North American forests. A method was developed to break seed dormancy of the herb garlic mustard using chemicals....

  13. Use of plant residues on growth of mycorrhizal seedlings of neem (Azadirachta indica A. Juss.).

    Science.gov (United States)

    Monte Júnior, Inácio P; Maia, Leonor C; Silva, Fábio S B; Cavalcante, Uided M T

    2012-02-01

    Owing to its multiple uses in veterinary medicine, biofertilizers, pest control, etc., the commercial cultivation of neem (Azadirachta indica) has been increasing in various countries. The use of arbuscular mycorrhizal fungi (AMF) and plant by-products (composted leaves and residues of neem and sugarcane) for the propagation of seedlings can be an efficient alternative to stimulate plant growth, reducing the propagation time and conferring increased tolerance of plants to biotic and abiotic stresses. Therefore this study aimed to evaluate the effect of plant substrates and inoculation with AMF on the production of neem seedlings. Beneficial effects of the application of neem by-products to neem seedlings were observed on most of the variables analysed. However, the treatment with sugarcane cake did not improve the growth of neem seedlings. In general, the inoculation treatments using Glomus etunicatum in the composted neem substrates improved seedling growth. Neem by-products benefit the growth of seedlings of this plant under greenhouse conditions. Inoculation with G. etunicatum enhances plants growth mainly in substrates with residues of neem leaves, providing an alternative for the production of seedlings of this crop under nursery conditions, which can reduce the need for chemical fertilizers that impact the environment. Copyright © 2011 Society of Chemical Industry.

  14. Plant species differ in early seedling growth and tissue nutrient responses to arbuscular and ectomycorrhizal fungi.

    Science.gov (United States)

    Holste, Ellen K; Kobe, Richard K; Gehring, Catherine A

    2017-04-01

    Experiments with plant species that can host both arbuscular mycorrhizal fungi (AMF) and ectomycorrhizal fungi (EMF) are important to separating the roles of fungal type and plant species and understanding the influence of the types of symbioses on plant growth and nutrient acquisition. We examined the effects of mycorrhizal fungal type on the growth and tissue nutrient content of two tree species (Eucalyptus grandis and Quercus costaricensis) grown under four nutrient treatments (combinations of low versus high nitrogen (N) and phosphorus (P) with different N:P ratios) in the greenhouse. Trees were inoculated with unidentified field mixtures of AMF or EMF species cultivated on root fragments of AMF- or EMF-specific bait plants. In E. grandis, inoculation with both AMF and EMF positively affected belowground plant dry weight and negatively affected aboveground dry weight, while only inoculation with AMF increased tissue nutrient content. Conversely, Q. costaricensis dry weight and nutrient content did not differ significantly among inoculation treatments, potentially due to its dependence on cotyledon reserves for growth. Mineral nutrition of both tree species differed with the ratio of N to P applied while growth did not. Our results demonstrate that both tree species' characteristics and the soil nutrient environment can affect how AMF and EMF interact with their host plants. This research highlights the importance of mycorrhizal fungal-tree-soil interactions during early seedling growth and suggests that differences between AMF and EMF associations may be crucial to understanding forest ecosystem functioning.

  15. Stimulatory effects of arsenic-tolerant soil fungi on plant growth promotion and soil properties.

    Science.gov (United States)

    Srivastava, Pankaj Kumar; Shenoy, Belle Damodara; Gupta, Manjul; Vaish, Aradhana; Mannan, Shivee; Singh, Nandita; Tewari, Shri Krishna; Tripathi, Rudra Deo

    2012-01-01

    Fifteen fungi were obtained from arsenic-contaminated agricultural fields in West Bengal, India and examined for their arsenic tolerance and removal ability in our previous study. Of these, the four best arsenic-remediating isolates were tested for plant growth promotion effects on rice and pea in the present study. A greenhouse-based pot experiment was conducted using soil inocula of individual fungi. The results indicated a significant (Psoil properties in inoculated soils compared to the control. A significant increase in plant growth was recorded in treated soils and varied from 16-293%. Soil chemical and enzymatic properties varied from 20-222% and 34-760%, respectively, in inoculated soil. Plants inoculated with inocula of Westerdykella and Trichoderma showed better stimulatory effects on plant growth and soil nutrient availability than Rhizopus and Lasiodiplodia. These fungi improved soil nutrient content and enhanced plant growth. These fungi may be used as bioinoculants for plant growth promotion and improved soil properties in arsenic-contaminated agricultural soils.

  16. Regeneration and growth rates of allofragments in four common stream plants

    DEFF Research Database (Denmark)

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

    2009-01-01

    Colonisation by stream plants occurs to a large extent from simple stem fragments. Allofragments are stem fragments formed by mechanical breakage. We studied regeneration, colonisation, and growth rates in four common stream plants: Elodea canadensis Michx., Myriophyllum spicatum L., Potamogeton...... perfoliatus L. and Ranunculus baudotii x pseudofluitans. The objectives of this study were to determine (1) if shoots with an apical tip have higher regeneration (growth of new shoots and rhizomes from allofragments) and colonisation (root attachment in sediment) abilities and higher relative growth rates...

  17. Mirror Advanced Reactor Study (MARS). Final report. Volume 1-B. Commercial fusion electric plant

    Energy Technology Data Exchange (ETDEWEB)

    Donohue, M.L.; Price, M.E. (eds.)

    1984-07-01

    Volume 1-B contains the following chapters: (1) blanket and reflector; (2) central cell shield; (3) central cell structure; (4) heat transport and energy conversion; (5) tritium systems; (6) cryogenics; (7) maintenance; (8) safety; (9) radioactivity, activation, and waste disposal; (10) instrumentation and control; (11) balance of plant; (12) plant startup and operation; (13) plant availability; (14) plant construction; and (15) economic analysis.

  18. Plutonium Finishing Plant (PFP) Final Safety Analysis Report (FSAR) [SEC 1 THRU 11

    Energy Technology Data Exchange (ETDEWEB)

    ULLAH, M K

    2001-02-26

    The Plutonium Finishing Plant (PFP) is located on the US Department of Energy (DOE) Hanford Site in south central Washington State. The DOE Richland Operations (DOE-RL) Project Hanford Management Contract (PHMC) is with Fluor Hanford Inc. (FH). Westinghouse Safety Management Systems (WSMS) provides management support to the PFP facility. Since 1991, the mission of the PFP has changed from plutonium material processing to preparation for decontamination and decommissioning (D and D). The PFP is in transition between its previous mission and the proposed D and D mission. The objective of the transition is to place the facility into a stable state for long-term storage of plutonium materials before final disposition of the facility. Accordingly, this update of the Final Safety Analysis Report (FSAR) reflects the current status of the buildings, equipment, and operations during this transition. The primary product of the PFP was plutonium metal in the form of 2.2-kg, cylindrical ingots called buttoms. Plutonium nitrate was one of several chemical compounds containing plutonium that were produced as an intermediate processing product. Plutonium recovery was performed at the Plutonium Reclamation Facility (PRF) and plutonium conversion (from a nitrate form to a metal form) was performed at the Remote Mechanical C (RMC) Line as the primary processes. Plutonium oxide was also produced at the Remote Mechanical A (RMA) Line. Plutonium processed at the PFP contained both weapons-grade and fuels-grade plutonium materials. The capability existed to process both weapons-grade and fuels-grade material through the PRF and only weapons-grade material through the RMC Line although fuels-grade material was processed through the line before 1984. Amounts of these materials exist in storage throughout the facility in various residual forms left from previous years of operations.

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

    Science.gov (United States)

    Boldrin, Paulo F; de Figueiredo, Marislaine A; Yang, Yong; Luo, Hongmei; Giri, Shree; Hart, Jonathan J; Faquin, Valdemar; Guilherme, Luiz R G; Thannhauser, Theorodore W; Li, Li

    2016-09-01

    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 as on S level in seven wheat lines were examined. Low dosages of both selenate and selenite supplements were found to enhance wheat shoot biomass and show no inhibitory effect on grain production. The stimulation on plant growth was correlated with increased APX antioxidant enzyme activity. Se forms were found to exert different effects on S metabolism in wheat plants. Selenate treatment promoted S accumulation, which was not observed with selenite supplement. An over threefold increase of S levels following selenate treatment at low dosages was observed in shoots of all wheat lines. Analysis of the sulfate transporter gene expression revealed an increased transcription of SULTR1;1, SULTR1;3 and SULTR4;1 in roots following 10 μM Na2 SeO4 treatment. Mass spectrometry-based targeted protein quantification confirmed the gene expression results and showed enhanced protein levels. The results suggest that Se treatment mimics S deficiency to activate specific sulfate transporter expression to stimulate S uptake, resulting in the selenate-induced S accumulation. This study supports that plant growth and nutrition benefit from low dosages of Se fertilization and provides information on the basis underlying Se-induced S accumulation in plants.

  20. Impact of rhizobial inoculation and nitrogen utilization in plant growth promotion of maize (Zea mays L.

    Directory of Open Access Journals (Sweden)

    RAMESH K. SINGH

    2013-05-01

    Full Text Available Singh RK, Malik N, Singh S. 2013. Impact of rhizobial inoculation and nitrogen utilization in plant growth promotion of maize (Zea mays L.. Nusantara Bioscience 5: 8-14. During the course of growing population demands there has been an increasing interest in exploring the possibility of extending the beneficial interaction between cereals and plant growth promoting rhizobacteria (PGPR. Endophytes are a group of microorganism that resides mostly in the intercellular space of various parts of plants including cereals. Assessment of plant growth promoting properties of the five-rhizobial strains belonging to α subclass i.e. Rhizobium leguminosarum bv. phaseoli RRE6 and R. undicola RRE36 and those belonging to β subclass i.e. Burkholderia cepacia (RRE3, RRE5, RRE25 was done by growing maize plants inoculated with these strains. Inoculated maize plants showed a significant increase in plant height, root length, shoot and root dry weight over uninoculated control. R. leguminosarum bv. phaseoli RRE6 and B. cepacia RRE5 among the α and β-subclass representatives respectively, gave the best inoculation response. Effect of nitrate supplementation upon maize-RRE6 and RRE5 association was also studied and a significant increase in all the growth parameters and colonization ability was recorded when nitrate was present as a supplement over uninoculated control and maize-RRE6 and RRE5 in absence of external nitrate.