WorldWideScience

Sample records for plant physiological analysis

  1. Plant Physiology and Development

    DEFF Research Database (Denmark)

    Taiz, Lincoln; Zeiger, Eduardo; Møller, Ian Max

    Physiology and Development. As before, Unit III begins with updated chapters on Cell Walls and Signals and Signal Transduction. The latter chapter has been expanded to include a discussion of major signaling molecules, such as calcium ions and plant hormones. A new, unified chapter entitled Signals from......Throughout its twenty-two year history, the authors of Plant Physiology have continually updated the book to incorporate the latest advances in plant biology and implement pedagogical improvements requested by adopters. This has made Plant Physiology the most authoritative, comprehensive......, and widely used upper-division plant biology textbook. In the Sixth Edition, the Growth and Development section (Unit III) has been reorganized and expanded to present the complete life cycle of seed plants from germination to senescence. In recognition of this enhancement, the text has been renamed Plant...

  2. Causes of Low and High Citation Potentials in Science: Citation Analysis of Biochemistry and Plant Physiology Journals.

    Science.gov (United States)

    Marton, Janos

    1983-01-01

    Citation data of 16 biochemistry and plant physiology journals show that reasons for lower citation potentials of plant physiology articles are: (1) readership is narrower for plant physiology journals; (2) plant physiologists can cite fewer thematically relevant new articles; and (3) plant physiology research fields are more isolated. References…

  3. Polyamines in plant physiology

    Science.gov (United States)

    Galston, A. W.; Sawhney, R. K.

    1990-01-01

    The diamine putrescine, the triamine spermidine, and the tetramine spermine are ubiquitous in plant cells, while other polyamines are of more limited occurrence. Their chemistry and pathways of biosynthesis and metabolism are well characterized. They occur in the free form as cations, but are often conjugated to small molecules like phenolic acids and also to various macromolecules. Their titer varies from approximately micromolar to more than millimolar, and depends greatly on environmental conditions, especially stress. In cereals, the activity of one of the major polyamine biosynthetic enzymes, arginine decarboxylase, is rapidly and dramatically increased by almost every studied external stress, leading to 50-fold or greater increases in putrescine titer within a few hours. The physiological significance of this increase is not yet clear, although most recent work suggests an adaptive, protective role. Polyamines produced through the action of ornithine decarboxylase, by contrast, seem essential for DNA replication and cell division. The application of exogenous polyamines produces effects on patterns of senescence and morphogenesis, suggesting but not proving a regulatory role for polyamines in these processes. The evidence for such a regulatory role is growing.

  4. A meta-analysis of plant physiological and growth responses to temperature and elevated CO(2).

    Science.gov (United States)

    Wang, Dan; Heckathorn, Scott A; Wang, Xianzhong; Philpott, Stacy M

    2012-05-01

    Atmospheric carbon dioxide (CO(2)) and global mean temperature are expected to be significantly higher by the end of the 21st century. Elevated CO(2) (eCO(2)) and higher temperature each affect plant physiology and growth, but their interactive effects have not been reviewed statistically with respect to higher chronic mean temperatures and abrupt heat stress. In this meta-analysis, we examined the effect of CO(2) on the physiology and growth of plants subjected to different temperature treatments. The CO(2) treatments were categorized into ambient (560 ppm) levels, while temperature treatments were categorized into ambient temperature (AT), elevated temperature (ET; AT + 1.4-6°C), or heat stress (HS; AT + >8°C). Plant species were grouped according to photosynthetic pathways (C(3), C(4)), functional types (legumes, non-legumes), growth forms (herbaceous, woody), and economic purposes (crop, non-crop). eCO(2) enhanced net photosynthesis at AT, ET, and HS in C(3) species (especially at the HS level), but in C(4) species, it had no effect at AT, a positive effect at ET, and a negative effect at HS. The positive effect of eCO(2) on net photosynthesis was greater for legumes than for non-legumes at HS, for non-crops than crops at ET, and for woody than herbaceous species at ET and HS. Total (W (T)) and above- (W (AG)) and below-ground (W (BG)) biomass were increased by eCO(2) for most species groups at all temperatures, except for C(4) species and W (BG) of legumes at HS. Hence, eCO(2) × heat effects on growth were often not explained by effects on net photosynthesis. Overall, the results show that eCO(2) effects on plant physiology and growth vary under different temperature regimes, among functional groups and photosynthetic pathways, and among response variables. These findings have important implications for biomass accumulation and ecosystem functioning in the future when the CO(2) level is higher and climate extremes, such as heat waves, become more frequent.

  5. Protocol: optimising hydroponic growth systems for nutritional and physiological analysis of Arabidopsis thaliana and other plants

    Science.gov (United States)

    2013-01-01

    Background Hydroponic growth systems are a convenient platform for studying whole plant physiology. However, we found through trialling systems as they are described in the literature that our experiments were frequently confounded by factors that affected plant growth, including algal contamination and hypoxia. We also found the way in which the plants were grown made them poorly amenable to a number of common physiological assays. Results The drivers for the development of this hydroponic system were: 1) the exclusion of light from the growth solution; 2) to simplify the handling of individual plants, and 3) the growth of the plant to allow easy implementation of multiple assays. These aims were all met by the use of pierced lids of black microcentrifuge tubes. Seed was germinated on a lid filled with an agar-containing germination media immersed in the same solution. Following germination, the liquid growth media was exchanged with the experimental solution, and after 14-21 days seedlings were transferred to larger tanks with aerated solution where they remained until experimentation. We provide details of the protocol including composition of the basal growth solution, and separate solutions with altered calcium, magnesium, potassium or sodium supply whilst maintaining the activity of the majority of other ions. We demonstrate the adaptability of this system for: gas exchange measurement on single leaves and whole plants; qRT-PCR to probe the transcriptional response of roots or shoots to altered nutrient composition in the growth solution (we demonstrate this using high and low calcium supply); producing highly competent mesophyll protoplasts; and, accelerating the screening of Arabidopsis transformants. This system is also ideal for manipulating plants for micropipette techniques such as electrophysiology or SiCSA. Conclusions We present an optimised plant hydroponic culture system that can be quickly and cheaply constructed, and produces plants with similar

  6. Evolutionary plant physiology: Charles Darwin's forgotten synthesis

    Science.gov (United States)

    Kutschera, Ulrich; Niklas, Karl J.

    2009-11-01

    Charles Darwin dedicated more than 20 years of his life to a variety of investigations on higher plants (angiosperms). It has been implicitly assumed that these studies in the fields of descriptive botany and experimental plant physiology were carried out to corroborate his principle of descent with modification. However, Darwin’s son Francis, who was a professional plant biologist, pointed out that the interests of his father were both of a physiological and an evolutionary nature. In this article, we describe Darwin’s work on the physiology of higher plants from a modern perspective, with reference to the following topics: circumnutations, tropisms and the endogenous oscillator model; the evolutionary patterns of auxin action; the root-brain hypothesis; phloem structure and photosynthesis research; endosymbioses and growth-promoting bacteria; photomorphogenesis and phenotypic plasticity; basal metabolic rate, the Pfeffer-Kleiber relationship and metabolic optimality theory with respect to adaptive evolution; and developmental constraints versus functional equivalence in relationship to directional natural selection. Based on a review of these various fields of inquiry, we deduce the existence of a Darwinian (evolutionary) approach to plant physiology and define this emerging scientific discipline as the experimental study and theoretical analysis of the functions of green, sessile organisms from a phylogenetic perspective.

  7. Plant performance: a physiological and genetic analysis using Arabidopsis thaliana natural variation

    NARCIS (Netherlands)

    El-Lithy, M.E.M.

    2005-01-01

    Plant performance implies complex traits, controlled by a large set of genes and affected by the environment. In this thesis we have tried to take the first steps in unravelling the genes controlling plant performance using naturally occurring accessions (ecotypes) of the model plant Arabidopsis

  8. Physiological conjunction of allelochemicals and desert plants.

    Science.gov (United States)

    Yosef Friedjung, Avital; Choudhary, Sikander Pal; Dudai, Nativ; Rachmilevitch, Shimon

    2013-01-01

    Plants exchange signals with other physical and biological entities in their habitat, a form of communication termed allelopathy. The underlying principles of allelopathy and secondary-metabolite production are still poorly understood, especially in desert plants. The coordination and role of secondary metabolites were examined as a cause of allelopathy in plants thriving under arid and semiarid soil conditions. Desert plant species, Origanum dayi, Artemisia sieberi and Artemisia judaica from two different sources (cultivar cuttings and wild seeds) were studied in their natural habitats. Growth rate, relative water content, osmotic potential, photochemical efficiency, volatile composition and vital factors of allelopathy were analyzed at regular intervals along four seasons with winter showing optimum soil water content and summer showing water deficit conditions. A comprehensive analysis of the volatile composition of the leaves, ambient air and soil in the biological niche of the plants under study was carried out to determine the effects of soil water conditions and sample plants on the surrounding flora. Significant morpho-physiological changes were observed across the seasons and along different soil water content. Metabolic analysis showed that water deficit was the key for driving selective metabolomic shifts. A. judaica showed the least metabolic shifts, while A. sieberi showed the highest shifts. All the species exhibited high allelopathic effects; A. judaica displayed relatively higher growth-inhibition effects, while O. dayi showed comparatively higher germination-inhibition effects in germination assays. The current study may help in understanding plant behavior, mechanisms underlying secondary-metabolite production in water deficit conditions and metabolite-physiological interrelationship with allelopathy in desert plants, and can help cull economic benefits from the produced volatiles.

  9. Physiological conjunction of allelochemicals and desert plants.

    Directory of Open Access Journals (Sweden)

    Avital Yosef Friedjung

    Full Text Available Plants exchange signals with other physical and biological entities in their habitat, a form of communication termed allelopathy. The underlying principles of allelopathy and secondary-metabolite production are still poorly understood, especially in desert plants. The coordination and role of secondary metabolites were examined as a cause of allelopathy in plants thriving under arid and semiarid soil conditions. Desert plant species, Origanum dayi, Artemisia sieberi and Artemisia judaica from two different sources (cultivar cuttings and wild seeds were studied in their natural habitats. Growth rate, relative water content, osmotic potential, photochemical efficiency, volatile composition and vital factors of allelopathy were analyzed at regular intervals along four seasons with winter showing optimum soil water content and summer showing water deficit conditions. A comprehensive analysis of the volatile composition of the leaves, ambient air and soil in the biological niche of the plants under study was carried out to determine the effects of soil water conditions and sample plants on the surrounding flora. Significant morpho-physiological changes were observed across the seasons and along different soil water content. Metabolic analysis showed that water deficit was the key for driving selective metabolomic shifts. A. judaica showed the least metabolic shifts, while A. sieberi showed the highest shifts. All the species exhibited high allelopathic effects; A. judaica displayed relatively higher growth-inhibition effects, while O. dayi showed comparatively higher germination-inhibition effects in germination assays. The current study may help in understanding plant behavior, mechanisms underlying secondary-metabolite production in water deficit conditions and metabolite-physiological interrelationship with allelopathy in desert plants, and can help cull economic benefits from the produced volatiles.

  10. Some Recent Advances in Plant Physiology

    Science.gov (United States)

    Stafford, G. A.

    1972-01-01

    A popular review of plant physiological research, emphasizing those apsects of plant metabolism where there has been a recent shift in emphasis that is not yet reflected in secondary school advanced texts. (AL)

  11. The disadvantages of being a hybrid during drought: A combined analysis of plant morphology, physiology and leaf proteome in maize.

    Science.gov (United States)

    Holá, Dana; Benešová, Monika; Fischer, Lukáš; Haisel, Daniel; Hnilička, František; Hniličková, Helena; Jedelský, Petr L; Kočová, Marie; Procházková, Dagmar; Rothová, Olga; Tůmová, Lenka; Wilhelmová, Naďa

    2017-01-01

    A comparative analysis of various parameters that characterize plant morphology, growth, water status, photosynthesis, cell damage, and antioxidative and osmoprotective systems together with an iTRAQ analysis of the leaf proteome was performed in two inbred lines of maize (Zea mays L.) differing in drought susceptibility and their reciprocal F1 hybrids. The aim of this study was to dissect the parent-hybrid relationships to better understand the mechanisms of the heterotic effect and its potential association with the stress response. The results clearly showed that the four examined genotypes have completely different strategies for coping with limited water availability and that the inherent properties of the F1 hybrids, i.e. positive heterosis in morphological parameters (or, more generally, a larger plant body) becomes a distinct disadvantage when the water supply is limited. However, although a greater loss of photosynthetic efficiency was an inherent disadvantage, the precise causes and consequences of the original predisposition towards faster growth and biomass accumulation differed even between reciprocal hybrids. Both maternal and paternal parents could be imitated by their progeny in some aspects of the drought response (e.g., the absence of general protein down-regulation, changes in the levels of some carbon fixation or other photosynthetic proteins). Nevertheless, other features (e.g., dehydrin or light-harvesting protein contents, reduced chloroplast proteosynthesis) were quite unique to a particular hybrid. Our study also confirmed that the strategy for leaving stomata open even when the water supply is limited (coupled to a smaller body size and some other physiological properties), observed in one of our inbred lines, is associated with drought-resistance not only during mild drought (as we showed previously) but also during more severe drought conditions.

  12. Plant physiology for profitable pastures

    Science.gov (United States)

    A basic question of pasture-based livestock production is whether producers should manage pastures on the basis of what is best for the animal or what is best for the plant. Given that pastures are the principal and most economical source of feed, producers should carefully consider how they manage...

  13. Elements of plant physiology in theophrastus' botany.

    Science.gov (United States)

    Pennazio, Sergio

    2014-01-01

    For thousands of years the plants were considered only as a source of food and medicine, and as ornamental objects. Only from the fifth century BC, some philosophers of Ancient Greece realized that the plants were living organisms but, unfortunately, their works have come to us as fragments that we often know from the biological works of Aristotle. This eminent philosopher and man of science, however, did not give us a complete work on the plants, which he often promised to write. From scattered fragments of his conspicuous biological work, it emerges a concept of nutritive soul that, in the presence of heat and moisture, allows plants to grow and reproduce. The task of writing a comprehensive botanical work was delegated to his first pupil, Theophrastus, who left us two treatises over time translated into the various languages up to the current versions (Enquiry into plants, On the causes of plants). The plant life is described and interpreted on the basis of highly accurate observations. The physiological part of his botany is essentially the nutrition: According to Theophrastus, plants get matter and moisture from the soil through root uptake and process the absorbed substances transforming them into food, thanks to the heat. The processing (pepsis, coction) of matter into the food represents an extraordinary physiological intuition because individual organs of a plant appear to perform its specific transformation. Despite that Theophrastus did not do scientific experiments or use special methods other than the sharpness of his observations, he can be considered the forerunner of a plant physiology that would take rebirth only after two millennia.

  14. Physiological functions of plant cell coverings.

    Science.gov (United States)

    Hoson, Takayuki

    2002-08-01

    The cell coverings of plants have two important functions in plant life. Plant cell coverings are deeply involved in the regulation of the life cycle of plants: each stage of the life cycle, such as germination, vegetative growth, reproductive growth, and senescence, is strongly influenced by the nature of the cell coverings. Also, the apoplast, which consists of the cell coverings, is the field where plant cells first encounter the outer environment, and so becomes the major site of plant responses to the environment. In the regulation of each stage of the life cycle and the response to each environmental signal, some specific constituents of the cell coverings, such as xyloglucans in dicotyledons and 1,3,1,4-beta-glucans in Gramineae, act as the key component. The physiological functions of plant cell coverings are sustained by the metabolic turnover of these components. The components of the cell coverings are supplied from the symplast, but then they are modified or degraded in the apoplast. Thus, the metabolism of the cell coverings is regulated through the cross-talk between the symplast and the apoplast. The understanding of physiological functions of plant cell coverings will be greatly advanced by the use of genomic approaches. At the same time, we need to introduce nanobiological techniques for clarifying the minute changes in the cell coverings that occur in a small part within each cell.

  15. Physiological phenotyping of plants for crop improvement.

    Science.gov (United States)

    Ghanem, Michel Edmond; Marrou, Hélène; Sinclair, Thomas R

    2015-03-01

    Future progress in crop breeding requires a new emphasis in plant physiological phenotyping for specific, well-defined traits. Success in physiological phenotyping to identify parents for use in breeding efforts for improved cultivars has been achieved by employing a multi-tier screening approach with different levels of sophistication and trait resolution. Subsequently, cultivar development required an integrated mix of classical breeding approaches and one or more tiers of phenotyping to identify genotypes expressing the desired trait. The role of high throughput systems can be useful; here, we emphasize that this approach is likely to offer useful results at an initial tier of phenotyping and will need to be complemented with more directed tiers of phenotyping. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Fatality of salt stress to plants: Morphological, physiological and ...

    African Journals Online (AJOL)

    Fatality of salt stress to plants: Morphological, physiological and biochemical aspects. ... African Journal of Biotechnology ... Soil salinity affects various physiological and biochemical processes which result in reduced biomass production.

  17. Morphological and Physiological Responses of Strawberry Plants to Water Stress

    OpenAIRE

    Krzysztof Klamkowski; Waldemar Treder

    2006-01-01

    The most of previous studies have been focused on the effect of water stress on plant yielding. However, the conditions in which plants grow from the moment of planting might affect their morphology and physiological response. The aim of this study was to examine the effect of water deficiency on growth and plant physiological response of strawberry (Fragaria x ananassa Duch. cv. ‘Salut’) under greenhouse conditions. The plants were grown in plastic containers filled with peat substratum. Wat...

  18. Physiological blockage in plants in response to postharvest stress ...

    African Journals Online (AJOL)

    Physiological blockage in plants in response to postharvest stress. ... African Journal of Biotechnology. Journal Home · ABOUT ... However, ornamental plants are used in floral arrangements in vases and have limited shelf-life. Thus, this study ...

  19. Knowledge about plant is basis for successful cultivation : new international standard handbook on plant physiology

    NARCIS (Netherlands)

    Esch, van H.; Heuvelink, E.; Kierkels, T.

    2015-01-01

    Plant physiology in Greenhouses’ is the new international standard handbook on plant knowledge for the commercial greenhouse grower. It relates the functioning of the plant to the rapid developments in greenhouse cultivation. It is based on a continuing series of plant physiology articles published

  20. Plant Sterols: Diversity, Biosynthesis, and Physiological Functions.

    Science.gov (United States)

    Valitova, J N; Sulkarnayeva, A G; Minibayeva, F V

    2016-08-01

    Sterols, which are isoprenoid derivatives, are structural components of biological membranes. Special attention is now being given not only to their structure and function, but also to their regulatory roles in plants. Plant sterols have diverse composition; they exist as free sterols, sterol esters with higher fatty acids, sterol glycosides, and acylsterol glycosides, which are absent in animal cells. This diversity of types of phytosterols determines a wide spectrum of functions they play in plant life. Sterols are precursors of a group of plant hormones, the brassinosteroids, which regulate plant growth and development. Furthermore, sterols participate in transmembrane signal transduction by forming lipid microdomains. The predominant sterols in plants are β-sitosterol, campesterol, and stigmasterol. These sterols differ in the presence of a methyl or an ethyl group in the side chain at the 24th carbon atom and are named methylsterols or ethylsterols, respectively. The balance between 24-methylsterols and 24-ethylsterols is specific for individual plant species. The present review focuses on the key stages of plant sterol biosynthesis that determine the ratios between the different types of sterols, and the crosstalk between the sterol and sphingolipid pathways. The main enzymes involved in plant sterol biosynthesis are 3-hydroxy-3-methylglutaryl-CoA reductase, C24-sterol methyltransferase, and C22-sterol desaturase. These enzymes are responsible for maintaining the optimal balance between sterols. Regulation of the ratios between the different types of sterols and sterols/sphingolipids can be of crucial importance in the responses of plants to stresses.

  1. Water in the physiology of plant: thermodynamics and kinetic

    Directory of Open Access Journals (Sweden)

    Maurizio Cocucci

    2011-02-01

    Full Text Available Molecular properties of water molecule determine its role in plant physiology. At molecular level the properties of water molecules determine the behaviour of other plant molecules; in particular its physic characteristics are important in the operativeness of macromolecules and in plant thermoregulation. Plant water supply primarily dependent on thermodynamics properties in particular water chemical potential and its components, more recently there are evidences that suggest an important role in the water kinetic characteristics, depending, at cell membrane level, in particular plasmalemma, on the presence of specific water channel, the aquaporines controlled in its activity by a number of physiological and biochemical factors. Thermodynamics and kinetic factors controlled by physiological, biochemical properties and molecular effectors, control water supply and level in plants to realize their survival, growth and differentiation and the consequent plant production.

  2. Electrical signals and their physiological significance in plants.

    Science.gov (United States)

    Fromm, Jörg; Lautner, Silke

    2007-03-01

    Electrical excitability and signalling, frequently associated with rapid responses to environmental stimuli, are well known in some algae and higher plants. The presence of electrical signals, such as action potentials (AP), in both animal and plant cells suggested that plant cells, too, make use of ion channels to transmit information over long distances. In the light of rapid progress in plant biology during the past decade, the assumption that electrical signals do not only trigger rapid leaf movements in 'sensitive' plants such as Mimosa pudica or Dionaea muscipula, but also physiological processes in ordinary plants proved to be correct. Summarizing recent progress in the field of electrical signalling in plants, the present review will focus on the generation and propagation of various electrical signals, their ways of transmission within the plant body and various physiological effects.

  3. Root bacterial endophytes alter plant phenotype, but not physiology

    DEFF Research Database (Denmark)

    Henning, Jeremiah A.; Weston, David J.; Pelletier, Dale A.

    2016-01-01

    Plant traits, such as root and leaf area, influence how plants interact with their environment and the diverse microbiota living within plants can influence plant morphology and physiology. Here, we explored how three bacterial strains isolated from the Populus root microbiome, influenced plant...... phenotype. We chose three bacterial strains that differed in predicted metabolic capabilities, plant hormone production and metabolism, and secondary metabolite synthesis. We inoculated each bacterial strain on a single genotype of Populus trichocarpa and measured the response of plant growth related traits...... (root:shoot, biomass production, root and leaf growth rates) and physiological traits (chlorophyll content, net photosynthesis, net photosynthesis at saturating light-Asat, and saturating CO2-Amax). Overall, we found that bacterial root endophyte infection increased root growth rate up to 184% and leaf...

  4. Potential physiological role of plant glycosidase inhibitors

    DEFF Research Database (Denmark)

    Bellincampi, D.; Carmadella, L.; Delcour, J.A.;

    2004-01-01

    Carbohydrate-active enzymes including glycosidases, transglycosidases, glycosyltransferases, polysaccharide lyases and carbohydrate esterases are responsible for the enzymatic processing of carbohydrates in plants. A number of carbohydrate-active enzymes are produced by microbial pathogens...... applications....

  5. Physiology of Plants, Science (Experimental): 5315.41.

    Science.gov (United States)

    Gunn, William C.

    This unit of instruction deals with the physiological activities of plants. Attention is focused on the principles which underlie the activities of the typical green land plant. Emphasis is placed on biological processes such as photosynthesis, water transport, light responses, mineral nutrition, reproduction, and growth. The prerequisite for…

  6. Physiological response of soybean genotypes to plant density

    NARCIS (Netherlands)

    Gan, Y.; Stulen, H.; Keulen, van H.; Kuiper, P.J.C.

    2002-01-01

    Response of soybean (Glycine max (L.) Merr.) to plant density has occupied a segment of agronomic research for most of the century. Genotype differences have been noted especially in response to planting date, lodging problems and water limitation. There is limited information on the physiological g

  7. Root bacterial endophytes alter plant phenotype, but not physiology

    Directory of Open Access Journals (Sweden)

    Jeremiah A. Henning

    2016-11-01

    Full Text Available Plant traits, such as root and leaf area, influence how plants interact with their environment and the diverse microbiota living within plants can influence plant morphology and physiology. Here, we explored how three bacterial strains isolated from the Populus root microbiome, influenced plant phenotype. We chose three bacterial strains that differed in predicted metabolic capabilities, plant hormone production and metabolism, and secondary metabolite synthesis. We inoculated each bacterial strain on a single genotype of Populus trichocarpa and measured the response of plant growth related traits (root:shoot, biomass production, root and leaf growth rates and physiological traits (chlorophyll content, net photosynthesis, net photosynthesis at saturating light–Asat, and saturating CO2–Amax. Overall, we found that bacterial root endophyte infection increased root growth rate up to 184% and leaf growth rate up to 137% relative to non-inoculated control plants, evidence that plants respond to bacteria by modifying morphology. However, endophyte inoculation had no influence on total plant biomass and photosynthetic traits (net photosynthesis, chlorophyll content. In sum, bacterial inoculation did not significantly increase plant carbon fixation and biomass, but their presence altered where and how carbon was being allocated in the plant host.

  8. Knowledge about plant is basis for successful cultivation : new international standard handbook on plant physiology

    OpenAIRE

    de Esch,, Hubert P. L.; Heuvelink, E.; Kierkels, T.

    2015-01-01

    Plant physiology in Greenhouses’ is the new international standard handbook on plant knowledge for the commercial greenhouse grower. It relates the functioning of the plant to the rapid developments in greenhouse cultivation. It is based on a continuing series of plant physiology articles published in the Dutch journal Onder Glas and the international edition In Greenhouses, written by Ep Heuvelink and Tijs Kierkels.

  9. Allocation, stress tolerance and carbon transport in plants: how does phloem physiology affect plant ecology?

    Science.gov (United States)

    Savage, Jessica A; Clearwater, Michael J; Haines, Dustin F; Klein, Tamir; Mencuccini, Maurizio; Sevanto, Sanna; Turgeon, Robert; Zhang, Cankui

    2016-04-01

    Despite the crucial role of carbon transport in whole plant physiology and its impact on plant-environment interactions and ecosystem function, relatively little research has tried to examine how phloem physiology impacts plant ecology. In this review, we highlight several areas of active research where inquiry into phloem physiology has increased our understanding of whole plant function and ecological processes. We consider how xylem-phloem interactions impact plant drought tolerance and reproduction, how phloem transport influences carbon allocation in trees and carbon cycling in ecosystems and how phloem function mediates plant relations with insects, pests, microbes and symbiotes. We argue that in spite of challenges that exist in studying phloem physiology, it is critical that we consider the role of this dynamic vascular system when examining the relationship between plants and their biotic and abiotic environment.

  10. Morphological and Physiological Responses of Strawberry Plants to Water Stress

    Directory of Open Access Journals (Sweden)

    Krzysztof Klamkowski

    2006-12-01

    Full Text Available The most of previous studies have been focused on the effect of water stress on plant yielding. However, the conditions in which plants grow from the moment of planting might affect their morphology and physiological response. The aim of this study was to examine the effect of water deficiency on growth and plant physiological response of strawberry (Fragaria x ananassa Duch. cv. ‘Salut’ under greenhouse conditions. The plants were grown in plastic containers filled with peat substratum. Water stress was imposed by reducing the irrigation according to substratum moisture readings. Water stressed plants had the lowest values of water potential and showed strong decrease in gas exchange rate. Also, biomass and leaf area were the lowest in this group of plants. No differences in the length of root system were observed between control and water stressed plants. The lack of water in growing medium resulted also in a decrease of density and reduction of dimensions of stomata on plant leaves. These changes contribute to optimizing the use of assimilates and water use efficiency in periods when water availability is decreased.

  11. Morphological and Physiological Responses of Strawberry Plants to Water Stress

    Directory of Open Access Journals (Sweden)

    Krzysztof Klamkowski

    2006-01-01

    Full Text Available The most of previous studies have been focused on the effect of water stress on plant yielding. However, the conditions in which plants grow from the moment of planting might affect their morphology and physiological response. The aim of this study was to examine the effect of water deficiency on growth and plant physiological response of strawberry (Fragaria x ananassa Duch. cv. ‘Salut’ under greenhouse conditions. The plants were grown in plastic containers filled with peat substratum. Water stress was imposed by reducing the irrigation according to substratum moisture readings. Water stressed plants had the lowest values of water potential and showed strong decrease in gas exchange rate. Also, biomass and leaf area were the lowest in this group of plants. No differences in the length of root system were observed between control and water stressed plants. The lack of water in growing medium resulted also in a decrease of density and reduction of dimensions of stomata on plant leaves.These changes contribute to optimizing the use of assimilates and water use efficiency in periods when water availability is decreased.

  12. Natural selection on plant physiological traits in an urban environment

    Science.gov (United States)

    Lambrecht, Susan C.; Mahieu, Stephanie; Cheptou, Pierre-Olivier

    2016-11-01

    Current rates of urbanization are creating new opportunities for studying urban plant ecology, but our knowledge of urban plant physiology lags behind that of other ecosystems. Moreover, higher temperatures, elevated CO2, and increased inorganic nitrogen deposition along with altered moisture regimes of urban as compared to rural areas creates a compelling analog for studying adaptations of plants to climate change. We grew plants under common conditions in a greenhouse to determine whether populations of Crepis sancta (Asteraceae) differed in phenological, morphological, and physiological traits. We also used a field experiment to test for natural selection on these traits in urban Montpellier, France. Urban plants flowered and senesced later than rural plants, and natural selection favored later phenology in the urban habitat. Natural selection also favored larger plants with more leaves, and increased photosynthesis and leaf nitrogen concentration. Ours is the first study to document selection on plant functional traits in an urban habitat and, as such, advances our understanding of urban plant ecology and possible adaptations to climate change.

  13. Urban plant physiology: adaptation-mitigation strategies under permanent stress.

    Science.gov (United States)

    Calfapietra, Carlo; Peñuelas, Josep; Niinemets, Ülo

    2015-02-01

    Urban environments that are stressful for plant function and growth will become increasingly widespread in future. In this opinion article, we define the concept of 'urban plant physiology', which focuses on plant responses and long term adaptations to urban conditions and on the capacity of urban vegetation to mitigate environmental hazards in urbanized settings such as air and soil pollution. Use of appropriate control treatments would allow for studies in urban environments to be comparable to expensive manipulative experiments. In this opinion article, we propose to couple two approaches, based either on environmental gradients or manipulated gradients, to develop the concept of urban plant physiology for assessing how single or multiple environmental factors affect the key environmental services provided by urban forests. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Physiological and ecological significance of biomineralization in plants.

    Science.gov (United States)

    He, Honghua; Veneklaas, Erik J; Kuo, John; Lambers, Hans

    2014-03-01

    Biomineralization is widespread in the plant kingdom. The most common types of biominerals in plants are calcium oxalate crystals, calcium carbonate, and silica. Functions of biominerals may depend on their shape, size, abundance, placement, and chemical composition. In this review we highlight advances in understanding physiological and ecological significance of biomineralization in plants. We focus on the functions of biomineralization in regulating cytoplasmic free calcium levels, detoxifying aluminum and heavy metals, light gathering and scattering to optimize photosynthesis, aiding in pollen release, germination, and tube growth, the roles it plays in herbivore deterrence, biogeochemical cycling of carbon, calcium, and silicon, and sequestering atmospheric CO2. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Seed isotopic analysis as a tool to understand ecological processes influencing plant development and physiology: the case study of Quercus rotundifolia Lam. in a desertification gradient in Mediterranean areas

    Science.gov (United States)

    Oliveira, Tatiana; Silva, Anabela; Rodrigues, Carla; Antunes Antunes, Cristina; Pinho, Pedro; Ramos, Alzira; João Pereira, Maria; Branquinho, Cristina; Máguas, Cristina

    2014-05-01

    Plant responses to climate change highly depend on the temporal variability in precipitation events and on plant specific strategies, such as drought tolerance and resilience. Within the different plant organs, seeds have become an important research tool in the past years to study plant development and nutrients allocation. Key features of seeds such as the tendency to accumulate and store nutrient compounds open many possibilities to explore isotope analysis (13C, 15N and 18O), with many outcomes in fields from ecology to food traceability. The application of light stable isotopes to plant materials have been used to study both physiological (i.e. photosynthesis and stomatal conductance), nutrients uptake and metabolism (origin of nitrogen and symbiotic associations) as well as many ecological processes, which will produce a distinctive isotope fingerprint on the plant tissues. Thus, the isotopic composition of certain bio and geo-elements of seeds, yielding relevant information on plant ecophysiology, are able to relate the plant functioning with local climatic conditions (e.g., temperature and precipitation). The application of isotope analysis in this way can be used as a proxy to understand complex environmental degradation processes such as land degradation in drylands resulting from various factors including climatic variations and human activities. In this study acorns of Quercus ilex plants were sampled during 2012-2013 in a region of southern Portugal, according to (i) soil land-use; (ii) aridity and desertification indexes. The approach developed combined plant seed analysis (seed morphology and compounds quantification) with isotope ratio mass spectrometry (δ13C, δ15N and δ18O) as a "tool" to study changes in plant ecophysiology over time and space. Seeds allow studies at specific temporal scale (development period) which varies according to its biology and depends on the climatic conditions where the plant is grown (i.e, seed's biomass integrate

  16. Physiological roles of plastid terminal oxidase in plant stress responses

    Indian Academy of Sciences (India)

    Xin Sun; Tao Wen

    2011-12-01

    The plastid terminal oxidase (PTOX) is a plastoquinol oxidase localized in the plastids of plants. It is able to transfer electrons from plastoquinone (PQ) to molecular oxygen with the formation of water. Recent studies have suggested that PTOX is beneficial for plants under environmental stresses, since it is involved in the synthesis of photoprotective carotenoids and chlororespiration, which could potentially protect the chloroplast electron transport chain (ETC) from over-reduction. The absence of PTOX in plants usually results in photo-bleached variegated leaves and impaired adaptation to environment alteration. Although PTOX level and activity has been found to increase under a wide range of stress conditions, the functions of plant PTOX in stress responses are still disputed now. In this paper, the possible physiological roles of PTOX in plant stress responses are discussed based on the recent progress.

  17. Circadian regulation of hormone signaling and plant physiology.

    Science.gov (United States)

    Atamian, Hagop S; Harmer, Stacey L

    2016-08-01

    The survival and reproduction of plants depend on their ability to cope with a wide range of daily and seasonal environmental fluctuations during their life cycle. Phytohormones are plant growth regulators that are involved in almost every aspect of growth and development as well as plant adaptation to myriad abiotic and biotic conditions. The circadian clock, an endogenous and cell-autonomous biological timekeeper that produces rhythmic outputs with close to 24-h rhythms, provides an adaptive advantage by synchronizing plant physiological and metabolic processes to the external environment. The circadian clock regulates phytohormone biosynthesis and signaling pathways to generate daily rhythms in hormone activity that fine-tune a range of plant processes, enhancing adaptation to local conditions. This review explores our current understanding of the interplay between the circadian clock and hormone signaling pathways.

  18. RESTORATIVE ASPECT OF CASTOR PLANT ON MAMMALIAN PHYSIOLOGY: A REVIEW

    Directory of Open Access Journals (Sweden)

    Attila Kádasi

    2011-10-01

    Full Text Available The castor plant (Ricinus communis L. is a robust perennial shrub of Euphorbiaceae family and different parts of the plant are widely used by various communities and forest dwellers in many regions of the world for treating a variety of ailments. About 80% of world population is still dependent on traditional herbal medicines. The plant is documented to possess beneficial effects as anti-oxidant, antifertility, anti inflammatory, antimicrobial, central nervous system stimulant, anti diabetic, insecticidal and larvicidal and many other medicinal properties. The extracts or the isolated compounds of this plant have been found to have potent activity against various ailments. The aim of this paper is to scrutinize the available literature related to the restorative activity of the castor plant as a herbal medicine on mammalian physiology and to accumulate those scientifically valid data in a nut shell in the form of a mini review.

  19. A Brief Analysis of Subcellular Distribution and Physiological Functions of Plant Aquaporins%植物水孔蛋白的亚细胞分布与生理功能研究浅析

    Institute of Scientific and Technical Information of China (English)

    庞永奇; 王高奇; 王旭初; 陈珈; 王学臣

    2012-01-01

    水孔蛋白(aquaporin,AQP)因具有水转运活性而得名,然而随着研究的深入,水孔蛋白转运活性的多样性与生理功能的多样性不断被报道.本文综合分析了植物水孔蛋白亚细胞定位与功能多样性的研究进展,重点综述了植物水孔蛋白广泛的亚细胞分布特点,以及亚细胞上的再分布现象与植物水孔蛋白生理功能多样性间的关系,并对植物水孔蛋白研究中存在的问题及研究方向进行了分析,认为水孔蛋白多样化的生理功能的作用机制需要结合其组织定位与亚细胞定位进行分析才能揭示.%Aquaporins (AQPs) got their name from the water transport ability, and recently, their multi-transport activities and multiple physiological functions were also frequently reported. This review focused on the analysis of recent progress on physiological functions and subcellular localizations of plant aquaporins. The relationship between the multi-physiological functionality and the multiple intracellular localizations and redistribution of plant aquaporins were also thoroughly discussed, thus raising questions about the current research and research direction for plant aquaporins. To reveal the possible mechanism on the multiple physiological functions, it is necessary and essential to analyze the connections between functions and tissue and subcellular localizations in future.

  20. Century long assessment of herbaceous plants' physiological responses to climate change in Switzerland

    Science.gov (United States)

    Moreno-Gutierrez, Cristina; Kahmen, Ansgar

    2017-04-01

    The isotopic analysis of archived plant material offers the exceptional opportunity to reconstruct the physiological activity of plants over long time periods and thus, to assess plant responses to environmental changes during the last centuries. In addition, the stable isotope analysis of herbarium samples offers the opportunity to reconstruct the physiological processes of a large range of different plant species and from different environments. Interestingly, only few studies have to date assessed these archives. We will present a novel analysis of leaf nitrogen, oxygen and carbon isotope ratios of more than a thousand herbarium specimens collected since 1800 until present from the unique herbaria hold at the University of Basel. The objective of our study was to assess century-long physiological responses of herbaceous plant species from different plant functional groups and along an altitudinal gradient in Switzerland. The goal of our study was to determine with our investigations the long-term responses of plants to climate change. Such investigations are important as they allow to assess long-term processes of acclimation and adaptation in plants to global enviromental change. In our study we found that herbaceous plants have increased their intrinsic water use efficiency in response to increasing atmospheric CO2 concentration but this increment was higher in plants from higher altitudes, due to the higher efficiency of CO2 assimilation of alpine plants compared to plants from lowlands. There were also differences among functional groups, with grasses and forbs showing the highest increments. In addition, herbaceous plants showed a decreasing trend with time in their N isotopic composition, which may indicate progressive N limitation due to higher biological activity with increasing atmospheric CO2 concentration.

  1. Molecular and physiological strategies to increase aluminum resistance in plants.

    Science.gov (United States)

    Inostroza-Blancheteau, Claudio; Rengel, Zed; Alberdi, Miren; de la Luz Mora, María; Aquea, Felipe; Arce-Johnson, Patricio; Reyes-Díaz, Marjorie

    2012-03-01

    Aluminum (Al) toxicity is a primary limitation to plant growth on acid soils. Root meristems are the first site for toxic Al accumulation, and therefore inhibition of root elongation is the most evident physiological manifestation of Al toxicity. Plants may resist Al toxicity by avoidance (Al exclusion) and/or tolerance mechanisms (detoxification of Al inside the cells). The Al exclusion involves the exudation of organic acid anions from the root apices, whereas tolerance mechanisms comprise internal Al detoxification by organic acid anions and enhanced scavenging of free oxygen radicals. One of the most important advances in understanding the molecular events associated with the Al exclusion mechanism was the identification of the ALMT1 gene (Al-activated malate transporter) in Triticum aestivum root cells, which codes for a plasma membrane anion channel that allows efflux of organic acid anions, such as malate, citrate or oxalate. On the other hand, the scavenging of free radicals is dependent on the expression of genes involved in antioxidant defenses, such as peroxidases (e.g. in Arabidopsis thaliana and Nicotiana tabacum), catalases (e.g. in Capsicum annuum), and the gene WMnSOD1 from T. aestivum. However, other recent findings show that reactive oxygen species (ROS) induced stress may be due to acidic (low pH) conditions rather than to Al stress. In this review, we summarize recent findings regarding molecular and physiological mechanisms of Al toxicity and resistance in higher plants. Advances have been made in understanding some of the underlying strategies that plants use to cope with Al toxicity. Furthermore, we discuss the physiological and molecular responses to Al toxicity, including genes involved in Al resistance that have been identified and characterized in several plant species. The better understanding of these strategies and mechanisms is essential for improving plant performance in acidic, Al-toxic soils.

  2. Small plants, large plants: the importance of plant size for the physiological ecology of vascular epiphytes.

    Science.gov (United States)

    Zotz, G; Hietz, P; Schmidt, G

    2001-10-01

    Recently, a number of publications have reported that many physiological properties of vascular epiphytes are a function of plant size. This short review will summarize what is known to date about this phenomenon, describe the possible mechanism and will discuss the consequences for the present understanding of epiphyte biology. Size-related changes are also known from other plant groups and it is argued that close attention should be paid to the size of the organisms under study in order to understand the performance and survival of a species in the field. In the light of these findings, the results of many earlier studies on epiphyte ecophysiology are now difficult to interpret because essential information on the size of the specimens used is missing.

  3. Impact of genomics approaches on plant genetics and physiology.

    Science.gov (United States)

    Tabata, Satoshi

    2002-08-01

    Comprehensive analysis of genetic information in higher plants is under way for several plants of biological and agronomical importance. Among them, Arabidopsis thaliana, a member of Brassica family, and Oryza sativa(rice) have been chosen as model plants most suitable for genome analysis. Sequencing of the genome of A. thaliana was completed in December 2000, and rice genome sequencing is in progress. The accumulated genome sequences, together with the hundreds of thousands of ESTs from several tens of plant species, have drastically changed the strategy of plant genetics. By utilizing the information on the genome and gene structures, comprehensive approaches for genome-wide functional analysis of the genes, including transcriptome analysis using microarray systems and a comprehensive analysis of a large number of insertion mutant lines, have been widely adopted. As a consequence, a large quantity of information on both the structure and function of genes in these model plants has been accumulated. However, other plant species may have their own characteristics and advantages to study individual phenomena. Application of knowledge from the model plants to other plant species and vice versa through the common language, namely the genome information, should facilitate understanding of the genetic systems underlying a variety of biological phenomena. Introduction of this common language may not be very simple, especially in the case of complex pathways such as a process of cell-covering formation. Nevertheless, it should be emphasized that genomics approaches are the most promising way to understand these processes.

  4. Physiological and biochemical responses of thyme plants to some antioxidants

    Directory of Open Access Journals (Sweden)

    SALWA A. ORABI

    2014-11-01

    Full Text Available Orabi SA, Talaat IM, Balbaa LK. 2014. Physiological and biochemical responses of thyme plants to some antioxidants. Nusantara Bioscience 6: 118-125. Two pot experiments were conducted to investigate the effect of tryptophan, nicotinamide and α-tocopherol (each at 50 and 100 mg/L on plant growth, essential oil yield and its main constituents. All treatments significantly promoted plant height, and increased fresh and dry mass (g/plant of thyme (Thymus vulgaris L.. The treatment with 100 mg/L nicotinamide showed increasing in total potassium mainly in the first cut. Total soluble sugars, oil percentage and oil yield and protein recorded increments with tryptophan treatments. Treatment of Thymus plants with 100 mg/L nicotinamide observed the highest percentage of thymol (67.61%. Oxygenated compounds recorded the highest value with 50 mg/L α-tocopherol treatment, while the maximum non-oxygenated ones resulted from the application of 100 mg/L nicotinamide. All treatments under study significantly affected the activity of oxidoreductase enzymes (POX and PPO. Nicotinamide at the concentration of 100 mg/L recorded the highest increments in APX and GR and the lowest values in oxidoreductase enzyme activities added to the lowest values of lipid peroxidation to enhance the best protection of thyme plants.

  5. Flowering plant physiology triggered the expansion of tropical rainforest

    Science.gov (United States)

    Lee, J.; Boyce, C. K.

    2009-12-01

    Transpiration has long been known to feed precipitation, but unique hydraulic characteristics of flowering plants recently have been recognized to impart transpiration capacities dramatically higher than any other plants, living or extinct. Here we show through climate modeling that the replacement of angiosperm with non-angiosperm vegetation would result in a hotter, drier, and more seasonal Amazon basin—dry season length increases by 80 days over the eastern Amazon and overall area of everwet conditions decreases by a factor of five. Evolution of angiosperm physiology has uniquely facilitated spread of warm everwet forests and their enormous biodiversity, perhaps including their early Cenozoic expansion to extra-tropical latitudes. Divergent responses may be expected to general climate parameters and discrete environmental perturbations before and after evolution of angiosperm dominated ecosystems.

  6. Evaluating physiological responses of plants to salinity stress

    KAUST Repository

    Negrão, S.

    2016-10-06

    Background Because soil salinity is a major abiotic constraint affecting crop yield, much research has been conducted to develop plants with improved salinity tolerance. Salinity stress impacts many aspects of a plant’s physiology, making it difficult to study in toto. Instead, it is more tractable to dissect the plant’s response into traits that are hypothesized to be involved in the overall tolerance of the plant to salinity. Scope and conclusions We discuss how to quantify the impact of salinity on different traits, such as relative growth rate, water relations, transpiration, transpiration use efficiency, ionic relations, photosynthesis, senescence, yield and yield components. We also suggest some guidelines to assist with the selection of appropriate experimental systems, imposition of salinity stress, and obtaining and analysing relevant physiological data using appropriate indices. We illustrate how these indices can be used to identify relationships amongst the proposed traits to identify which traits are the most important contributors to salinity tolerance. Salinity tolerance is complex and involves many genes, but progress has been made in studying the mechanisms underlying a plant’s response to salinity. Nevertheless, several previous studies on salinity tolerance could have benefited from improved experimental design. We hope that this paper will provide pertinent information to researchers on performing proficient assays and interpreting results from salinity tolerance experiments.

  7. Photosynthetic, Physiological and Biochemical Responses of Tomato Plants to Polyethylene Glycol-Induced Water Deficit

    Institute of Scientific and Technical Information of China (English)

    Hatem ZGALLA(I); Kathy STEPPE; Raoul LEMEUR

    2005-01-01

    Polyethylene glycol (PEG 6000)-induced water deficit causes physiological as well as biochemical changes in plants. The present study reports on the results of such changes in hydroponically grown tomato plants (Lycopersicon esculentum Mill. cv. Nikita). Plants were subjected to moderate and severe levels of water stress (i.e. water potentials in the nutrient solution of-0.51 and -1.22 MPa, respectively).Water stress markedly affected the parameters of gas exchange. Net photosynthetic rate (Pn) decreased with the induction of water stress. Accordingly, a decrease in the transpiration rate (E) was observed. The ratio of both (Pn/E) resulted in a decrease in water use efficiency. One of the possible reasons for the reduction in Pn is structural damage to the thylakoids, which affects the photosynthetic transport of electrons. This was indicated by an increase in non-photochemical quenching and a reduction in the quantum yield of photosystem Ⅱ. Furthermore, a decrease in both leaf water potential and leaf osmotic potential was observed, which resulted in a significant osmotic adjustment during stress conditions. Analysis of the physiological responses was complemented with a study on changes in proline content. In stressed plants, a 10-fold increase in proline content was detected compared with control plants. It is clear that water stress tolerance is the result of a cumulative action of various physiological and biochemical processes, all of which were affected by PEG 6000-induced water stress.

  8. Physiological parameters controlling plant-atmosphere ammonia exchange

    Science.gov (United States)

    Schjoerring, Jan K.; Husted, Søren; Mattsson, Marie

    Recent advances in characterizing the influence of different physiological and environmental parameters on NH 3 exchange between plants and the atmosphere are presented. A central parameter in controlling the rate and direction of NH 3 fluxes is the NH 3 compensation point. It may vary from below 1 to over 20 nmol NH 3 mol -1 air. High compensation points seem to be a result of high tissue N status, rapid absorption of NH +4 from the root medium and/or low activity of glutamine synthetase, a key enzyme in NH +4 assimilation. These conditions cause the NH +4 concentration in leaf apoplast and leaf cells to increase. The NH 3 compensation point also depends on plant developmental stage with peaks in NH 3 emission related to leaf senescence and N remobilization. The leaf temperature has a profound influence on the NH 3 compensation point: an increase in temperature from 15 to 30°C may cause a plant to switch from being a strong sink for atmospheric NH 3 to being a significant NH 3 source. Stomatal conductance for NH 3 relative to that of water vapour increases with tissue N status and with leaf senescence. At a given leaf temperature, the NH 3 compensation point can be successfully predicted on basis of the pH and NH +4 concentration in the apoplast of the mesophyll cells.

  9. Plant physiological, morphological and yield-related responses to night temperature changes across different species and plant functional types

    Directory of Open Access Journals (Sweden)

    Panpan Jing

    2016-11-01

    Full Text Available Land surface temperature over the past decades has shown a faster warming trend during the night than during the day. Extremely low night temperatures have occurred frequently due to the influence of land-sea thermal difference, topography and climate change. This asymmetric night temperature change is expected to affect plant ecophysiology and growth, as the plant carbon consumption processes could be affected more than the assimilation processes because photosynthesis in most plants occurs during the daytime whereas plant respiration occurs throughout the day. The effects of high night temperature (HNT and low night temperature (LNT on plant ecophysiological and growing processes and how the effects vary among different plant functional types (PFTs have not been analyzed extensively. In this meta-analysis, we examined the effect of HNT and LNT on plant physiology and growth across different PFTs and experimental settings. Plant species were grouped according to their photosynthetic pathways (C3, C4 and CAM, growth forms (herbaceous, woody, and economic purposes (crop, non-crop. We found that HNT and LNT both had a negative effect on plant yield, but the effect of HNT on plant yield was primarily related to a reduction in biomass allocation to reproduction organs and the effect of LNT on plant yield was more related to a negative effect on total biomass. Leaf growth was stimulated at HNT and suppressed at LNT. HNT accelerated plants ecophysiological processes, including photosynthesis and dark respiration, while LNT slowed these processes. Overall, the results showed that the effects of night temperature on plant physiology and growth varied between HNT and LNT, among the response variables and PFTs, and depended on the magnitude of temperature change and experimental design. These findings suggest complexities and challenges in seeking general patterns of terrestrial plant growth in HNT and LNT. The PFT specific responses of plants are

  10. 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

  11. What role does plant physiology play in limiting species distribution?

    Science.gov (United States)

    De Kauwe, M. G.; Medlyn, B. E.; Beaumont, L.; Duursma, R.; Baumgartner, J.

    2015-12-01

    To predict vulnerability of tree species to changes in climate, we need to understand what processes are currently limiting their distributions. Although the limits to distribution is among the most fundamental of ecological questions, there are few studies that determine quantitatively which processes can explain observed distributions. Focusing on two contrasting Eucalypt species, a fast-growing coastal species (E. saligna) and a slower-growing inland species (E. sideroxylon), we examined to what extent plant physiological characteristics limit species distributions. The ecophysiology of both species has been extensively characterised in both controlled and field environments. We parameterised an ecosystem model (GDAY, Generic Decomposition and Yield) for both species, using the best available experimental data. We then used the model to predict the spatial distribution of productivity for these species in eastern Australia, and compared these predictions with the actual distributions. The results of this comparison allow us to identify where the distributions of these species are limited by physiological constraints on productivity, and consequently their vulnerability to changes in climate.

  12. Physiological responses of plant leaves to atmospheric ammonia and ammonium

    Science.gov (United States)

    Pearson, J.; Soares, A.

    Misting of leaves of several plant species with 3 mM aqueous NH +4 at pH 5, or fumigation with 3000 μg m -3 gaseous NH 3 for 1 h, elicits similar biochemical and physiological changes in the species tested. The enzyme glutamine synthetase (GS) was shown to increase its activity in all species, while that of nitrate reductase (NR) was inhibited, at least in those species which possessed the ability to induce foliar NR. At the same time there were marked changes in organic anion concentrations, with malate and citrate in particular being reduced in concentration, following either NH +4 or NH 3 application to leaves. The changes in organic anions are also discussed in the light of pH regulation by the cell. A stimulation of photosynthesis was also evident when leaves were treated with either NH 3 or NH +4. It is argued that, because of the differences in solution chemistry of the two ammonia forms, the aqueous form applied at pH 5 and the gaseous form being an alkali in solution, these changes can only have occurred through the ability of the leaves to readily assimilate both forms of the ammonia. The biochemical changes might have potential as markers for the onset of physiological perturbation by atmospheric ammonia pollution, particularly changes in organic acid concentration; their use in an index of pollution stress is briefly discussed.

  13. Environmental Nanoparticles Interactions with Plants: Morphological, Physiological, and Genotoxic Aspects

    Directory of Open Access Journals (Sweden)

    C. Remédios

    2012-01-01

    Full Text Available Nanoparticles (NPs are characterized by their small size (less than 100 nm and large surface area, which confer specific physicochemical properties as strength, electrical, and optical features. NPs can be derived from natural or anthropic sources, such as engineered or unwanted/incidental NPs. The composition, dimension, and morphology of engineered NPs enable their use in a variety of areas, such as electronic, biomedical, pharmaceutical, cosmetic, energy, environmental, catalysis, and materials science. As nanotechnology is an innovative and scientific growth area with an exponential production, more information is needed concerning the impacts of these nanomaterials (NMs in the environment and, particularly, in animals/humans health and in plants performance. So, research on NPs as emerging contaminants is therefore a new field in environmental health. This minireview describes, briefly, the NPs characterization and their occurrence in the environment stating air, water, and soil. Finally, particular emphasis is given to the interaction of NPs with plants at different levels: morphology, physiology, and genotoxicity. By analyzing this compiled information, it is evident that research on NPs phytotoxicity is in the beginning, and more comprehensive studies are needed not only on NPs cytotoxicity and genotoxicity but also on the best and the most reliable methods of assessing NPs toxicity.

  14. Alteration of plant physiology by glyphosate and its by-product aminomethylphosphonic acid: an overview.

    Science.gov (United States)

    Gomes, Marcelo P; Smedbol, Elise; Chalifour, Annie; Hénault-Ethier, Louise; Labrecque, Michel; Lepage, Laurent; Lucotte, Marc; Juneau, Philippe

    2014-09-01

    It is generally claimed that glyphosate kills undesired plants by affecting the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme, disturbing the shikimate pathway. However, the mechanisms leading to plant death may also be related to secondary or indirect effects of glyphosate on plant physiology. Moreover, some plants can metabolize glyphosate to aminomethylphosphonic acid (AMPA) or be exposed to AMPA from different environmental matrices. AMPA is a recognized phytotoxin, and its co-occurrence with glyphosate could modify the effects of glyphosate on plant physiology. The present review provides an overall picture of alterations of plant physiology caused by environmental exposure to glyphosate and its metabolite AMPA, and summarizes their effects on several physiological processes. It particularly focuses on photosynthesis, from photochemical events to C assimilation and translocation, as well as oxidative stress. The effects of glyphosate and AMPA on several plant physiological processes have been linked, with the aim of better understanding their phytotoxicity and glyphosate herbicidal effects.

  15. Potassium-modulated physiological performance of mango plants infected by Ceratocystis fimbriata

    Directory of Open Access Journals (Sweden)

    Isaias Severino Cacique

    2017-08-01

    Full Text Available ABSTRACT Mango wilt, caused by the fungus Ceratocystis fimbriata, is an important disease affecting mango production. In view of the beneficial effects of potassium (K in other profitable crops and the lack of information about the effect of macronutrients on mango wilt development, the present study aimed to evaluate how mango plants supplied with K respond physiologically when infected by C. fimbriata. Mango plants (» 3 years old from cultivar Ubá were grown in plastic pots containing 58 mg of K·dm−3 (original K level based on the chemical analysis of the substrate or in plastic pots with substrate amended with a solution of 0.5 M potassium chloride (KCl to achieve the rate of 240 mg K·dm−3. Disease symptoms were more pronounced in inoculated plants grown at the lower K level. Substantial declines in stomatal conductance, in line with decreases in the internal-to-ambient CO2 concentration ratio and the absence of detectable changes in the chlorophyll a fluorescence parameters, suggest that the decrease in the net carbon assimilation rate is due, at least initially, to stomatal limitations. High concentrations of K and manganese were found in the stem tissues of inoculated plants and supplied with the highest K rate, most likely due to the involvement of these tissues in the local development of defense mechanisms. The results of this study suggest that the supply of K favored the physiological performance of mango plants and their resistance against C. fimbriata infection.

  16. How to Do It. Plant Eco-Physiology: Experiments on Crassulacean Acid Metabolism, Using Minimal Equipment.

    Science.gov (United States)

    Friend, Douglas J. C.

    1990-01-01

    Features of Crassulacean Acid Metabolism plants are presented. Investigations of a complex eco-physiological plant adaptation to the problems of growth in an arid environment are discussed. Materials and procedures for these investigations are described. (CW)

  17. Pollen viability, physiology, and production of maize plants exposed to pyraclostrobin+epoxiconazole.

    Science.gov (United States)

    Junqueira, Verônica Barbosa; Costa, Alan Carlos; Boff, Tatiana; Müller, Caroline; Mendonça, Maria Andréia Corrêa; Batista, Priscila Ferreira

    2017-04-01

    The use of fungicides in maize has been more frequent due to an increase in the incidence of diseases and also the possible physiological benefits that some of these products may cause. However, some of these products (e.g., strobilurins and triazoles) may interfere with physiological processes and the formation of reproductive organs. Therefore, the effect of these products on plants at different developmental stages needs to be better understood to reduce losses and maximize production. The effect of the fungicide pyraclostrobin+epoxiconazole (P+E) was evaluated at different growth stages in meiosis, pollen grain viability and germination, physiology, and production of maize plants in the absence of disease. An experiment was carried out with the hybrid DKB390 PROII and the application of pyraclostrobin+epoxiconazole at the recommended dose and an untreated control at 3 different timings (S1 - V10; S2 - V14; S3 - R1) with 5 replications. Gas exchange, chlorophyll fluorescence, pollen viability and germination, as well as the hundred-grain weight were evaluated. Anthers were collected from plants of S1 for cytogenetic analysis. The fungicide pyraclostrobin+epoxiconazole reduced the viability of pollen grains (1.4%), but this was not enough to reduce production. Moreover, no differences were observed in any of the other parameters analyzed, suggesting that P+E at the recommended dose and the tested stages does not cause toxic effects.

  18. Biological significance of complex N-glycans in plants and their impact on plant physiology

    Directory of Open Access Journals (Sweden)

    Richard eStrasser

    2014-07-01

    Full Text Available Asparagine (N-linked protein glycosylation is a ubiquitous co- and post-translational modification which can alter the biological function of proteins and consequently affects the development, growth and physiology of organisms. Despite an increasing knowledge of N-glycan biosynthesis and processing, we still understand very little about the biological function of individual N-glycan structures in plants. In particular, the N-glycan processing steps mediated by Golgi-resident enzymes create a structurally diverse set of protein-linked carbohydrate structures. Some of these complex N-glycan modifications like the presence of beta1,2-xylose, core alpha1,3-fucose or the Lewis a-epitope are characteristic for plants and are evolutionary highly conserved. In mammals, complex N-glycans are involved in different cellular processes including molecular recognition and signalling events. By contrast, the complex N-glycan function is still largely unknown in plants. Here, in this short review I focus on important recent developments and discuss their implications for future research in plant glycobiology and plant biotechnology.

  19. Physiological Factors Analysis in Unpressurized Aircraft Cabins

    Science.gov (United States)

    Patrao, Luis; Zorro, Sara; Silva, Jorge

    2016-11-01

    Amateur and sports flight is an activity with growing numbers worldwide. However, the main cause of flight incidents and accidents is increasingly pilot error, for a number of reasons. Fatigue, sleep issues and hypoxia, among many others, are some that can be avoided, or, at least, mitigated. This article describes the analysis of psychological and physiological parameters during flight in unpressurized aircraft cabins. It relates cerebral oximetry and heart rate with altitude, as well as with flight phase. The study of those parameters might give clues on which variations represent a warning sign to the pilot, thus preventing incidents and accidents due to human factors. Results show that both cerebral oximetry and heart rate change along the flight and altitude in the alert pilot. The impaired pilot might not reveal these variations and, if this is detected, he can be warned in time.

  20. Regulation by arbuscular mycorrhizae of the integrated physiological response to salinity in plants: new challenges in physiological and molecular studies.

    Science.gov (United States)

    Ruiz-Lozano, Juan Manuel; Porcel, Rosa; Azcón, Charo; Aroca, Ricardo

    2012-06-01

    Excessive salt accumulation in soils is a major ecological and agronomical problem, in particular in arid and semi-arid areas. Excessive soil salinity affects the establishment, development, and growth of plants, resulting in important losses in productivity. Plants have evolved biochemical and molecular mechanisms that may act in a concerted manner and constitute the integrated physiological response to soil salinity. These include the synthesis and accumulation of compatible solutes to avoid cell dehydration and maintain root water uptake, the regulation of ion homeostasis to control ion uptake by roots, compartmentation and transport into shoots, the fine regulation of water uptake and distribution to plant tissues by the action of aquaporins, the reduction of oxidative damage through improved antioxidant capacity and the maintenance of photosynthesis at values adequate for plant growth. Arbuscular mycorrhizal (AM) symbiosis can help the host plants to cope with the detrimental effects of high soil salinity. There is evidence that AM symbiosis affects and regulates several of the above mentioned mechanisms, but the molecular bases of such effects are almost completely unknown. This review summarizes current knowledge about the effects of AM symbiosis on these physiological mechanisms, emphasizing new perspectives and challenges in physiological and molecular studies on salt-stress alleviation by AM symbiosis.

  1. Plant neighbor identity influences plant biochemistry and physiology related to defense

    Directory of Open Access Journals (Sweden)

    Callaway Ragan M

    2010-06-01

    Full Text Available Abstract Background Chemical and biological processes dictate an individual organism's ability to recognize and respond to other organisms. A small but growing body of evidence suggests that plants may be capable of recognizing and responding to neighboring plants in a species specific fashion. Here we tested whether or not individuals of the invasive exotic weed, Centaurea maculosa, would modulate their defensive strategy in response to different plant neighbors. Results In the greenhouse, C. maculosa individuals were paired with either conspecific (C. maculosa or heterospecific (Festuca idahoensis plant neighbors and elicited with the plant defense signaling molecule methyl jasmonate to mimic insect herbivory. We found that elicited C. maculosa plants grown with conspecific neighbors exhibited increased levels of total phenolics, whereas those grown with heterospecific neighbors allocated more resources towards growth. To further investigate these results in the field, we conducted a metabolomics analysis to explore chemical differences between individuals of C. maculosa growing in naturally occurring conspecific and heterospecific field stands. Similar to the greenhouse results, C. maculosa individuals accumulated higher levels of defense-related secondary metabolites and lower levels of primary metabolites when growing in conspecific versus heterospecific field stands. Leaf herbivory was similar in both stand types; however, a separate field study positively correlated specialist herbivore load with higher densities of C. maculosa conspecifics. Conclusions Our results suggest that an individual C. maculosa plant can change its defensive strategy based on the identity of its plant neighbors. This is likely to have important consequences for individual and community success.

  2. Dewpoint - unstudied factor in ecology, physiology and plant introduction

    Directory of Open Access Journals (Sweden)

    Prokhorov Alexey

    2015-12-01

    Study of the mechanism of the condensation of atmospheric moisture on the surface of the plant and allow for modification of plant breeding with pronounced effect and reduce the temperature dependence on the least insolation. Such plants could be beneficial in reducing costs for irrigation of crops, and in the fight against desertification. The study of the mechanism of the phenomenon, allow for modification and selection of plants with the most pronounced effect of lowering the temperature and the lowest dependent on insolation. The plants, which are more efficient moisture capacitors can bring huge benefits in reducing costs for irrigation of crops, and in the fight against desertification.

  3. Root growth, mycorrhization and physiological effects of plants growing on oil tailing sands

    Science.gov (United States)

    Boldt-Burisch, Katja M.; Naeth, Anne M.; Schneider, Bernd Uwe; Hüttl, Reinhard F.

    2015-04-01

    Surface mining creates large, intense disturbances of soils and produces large volumes of by-products and waste materials. After mining processes these materials often provide the basis for land reclamation and ecosystem restoration. In the present study, tailing sands (TS) and processed mature fine tailings (pMFT) from Fort McMurray (Alberta, Canada) were used. They represent challenging material for ecosystem rebuilding because of very low nutrient contents of TS and oil residuals, high density of MFT material. In this context, little is known about the interactions of pure TS, respectively mixtures of TS and MFT and root growth, mycorrhization and plant physiological effects. Four herbaceous plant species (Elymus trachycaulus, Koeleria macrantha, Deschampsia cespitosa, Lotus corniculatus) were chosen to investigate root development, chlorophyll fluorescence and mycorrhization intensity with and without application of Glomus mosseae (arbuscular mycorrhizae) on mainly tailing sands. Surprisingly both, plants growing on pure TS and plants growing on TS with additional AM-application showed mycorrhization of roots. In general, the mycorrhization intensity was lower for plants growing on pure tailings sands, but it is an interesting fact that there is a potential for mycorrhization available in tailing sands. The mycorrhizal intensity strongly increased with application of G. mosseae for K. macrantha and L. corniculatus and even more for E. trachycaulus. For D. cespitosa similar high mycorrhiza infection frequency was found for both variants, with and without AM-application. By the application of G. mosseae, root growth of E. trachycaulus and K. macrantha was significantly positively influenced. Analysis of leaf chlorophyll fluorescence showed no significant differences for E. trachycaulus but significant positive influence of mycorrhizal application on the physiological status of L. corniculatus. However, this effect could not be detected when TS was mixed with MFT

  4. Root bacterial endophytes alter plant phenotype, but not physiology

    DEFF Research Database (Denmark)

    Henning, Jeremiah A.; Weston, David J.; Pelletier, Dale A.;

    2016-01-01

    (root:shoot, biomass production, root and leaf growth rates) and physiological traits (chlorophyll content, net photosynthesis, net photosynthesis at saturating light-Asat, and saturating CO2-Amax). Overall, we found that bacterial root endophyte infection increased root growth rate up to 184% and leaf...

  5. Joint control of terrestrial gross primary productivity by plant phenology and physiology.

    Science.gov (United States)

    Xia, Jianyang; Niu, Shuli; Ciais, Philippe; Janssens, Ivan A; Chen, Jiquan; Ammann, Christof; Arain, Altaf; Blanken, Peter D; Cescatti, Alessandro; Bonal, Damien; Buchmann, Nina; Curtis, Peter S; Chen, Shiping; Dong, Jinwei; Flanagan, Lawrence B; Frankenberg, Christian; Georgiadis, Teodoro; Gough, Christopher M; Hui, Dafeng; Kiely, Gerard; Li, Jianwei; Lund, Magnus; Magliulo, Vincenzo; Marcolla, Barbara; Merbold, Lutz; Montagnani, Leonardo; Moors, Eddy J; Olesen, Jørgen E; Piao, Shilong; Raschi, Antonio; Roupsard, Olivier; Suyker, Andrew E; Urbaniak, Marek; Vaccari, Francesco P; Varlagin, Andrej; Vesala, Timo; Wilkinson, Matthew; Weng, Ensheng; Wohlfahrt, Georg; Yan, Liming; Luo, Yiqi

    2015-03-03

    Terrestrial gross primary productivity (GPP) varies greatly over time and space. A better understanding of this variability is necessary for more accurate predictions of the future climate-carbon cycle feedback. Recent studies have suggested that variability in GPP is driven by a broad range of biotic and abiotic factors operating mainly through changes in vegetation phenology and physiological processes. However, it is still unclear how plant phenology and physiology can be integrated to explain the spatiotemporal variability of terrestrial GPP. Based on analyses of eddy-covariance and satellite-derived data, we decomposed annual terrestrial GPP into the length of the CO2 uptake period (CUP) and the seasonal maximal capacity of CO2 uptake (GPPmax). The product of CUP and GPPmax explained >90% of the temporal GPP variability in most areas of North America during 2000-2010 and the spatial GPP variation among globally distributed eddy flux tower sites. It also explained GPP response to the European heatwave in 2003 (r(2) = 0.90) and GPP recovery after a fire disturbance in South Dakota (r(2) = 0.88). Additional analysis of the eddy-covariance flux data shows that the interbiome variation in annual GPP is better explained by that in GPPmax than CUP. These findings indicate that terrestrial GPP is jointly controlled by ecosystem-level plant phenology and photosynthetic capacity, and greater understanding of GPPmax and CUP responses to environmental and biological variations will, thus, improve predictions of GPP over time and space.

  6. Cell physiology of plants growing in cold environments.

    Science.gov (United States)

    Lütz, Cornelius

    2010-08-01

    The life of plants growing in cold extreme environments has been well investigated in terms of morphological, anatomical, and ecophysiological adaptations. In contrast, long-term cellular or metabolic studies have been performed by only a few groups. Moreover, a number of single reports exist, which often represent just a glimpse of plant behavior. The review draws together the literature which has focused on tissue and cellular adaptations mainly to low temperatures and high light. Most studies have been done with European alpine plants; comparably well studied are only two phanerogams found in the coastal Antarctic. Plant adaptation in northern polar regions has always been of interest in terms of ecophysiology and plant propagation, but nowadays, this interest extends to the effects of global warming. More recently, metabolic and cellular investigations have included cold and UV resistance mechanisms. Low-temperature stress resistance in plants from cold environments reflects the climate conditions at the growth sites. It is now a matter of molecular analyses to find the induced genes and their products such as chaperones or dehydrins responsible for this resistance. Development of plants under snow or pollen tube growth at 0 degrees C shows that cell biology is needed to explain the stability and function of the cytoskeleton. Many results in this field are based on laboratory studies, but several publications show that it is not difficult to study cellular mechanisms with the plants adapted to a natural stress. Studies on high light and UV loads may be split in two parts. Many reports describe natural UV as harmful for the plants, but these studies were mainly conducted by shielding off natural UV (as controls). Other experiments apply additional UV in the field and have had practically no negative impact on metabolism. The latter group is supported by the observations that green overwintering plants increase their flavonoids under snow even in the absence of

  7. Physiology

    Science.gov (United States)

    Kay, Ian

    2008-01-01

    Underlying recent developments in health care and new treatments for disease are advances in basic medical sciences. This edition of "Webwatch" focuses on sites dealing with basic medical sciences, with particular attention given to physiology. There is a vast amount of information on the web related to physiology. The sites that are included here…

  8. Air and the origin of the experimental plant physiology.

    Science.gov (United States)

    Pennazio, Sergio

    2005-01-01

    It is well known that oxygen and carbon dioxide are two chemicals which enter the plant metabolism as nutrients. The bases of this nowadays obvious statement were placed in the 18th century by means of the works of ingenious naturalists such as Robert Boyle, Stephen Hales, Joseph Priestley, Jam Ingenhousz, Lazzaro Spallanzani and Theodore De Saussure. Till the end of the 17th century, the atmospheric air was considered as an ineffable spirit, the function of which was of physical nature. Boyle was the first naturalist to admit the possibility that respiration were an exchange of vapours occurring in the blood. Stephen Hales realised that air could be fixed by plants under the influence of solar light. Priestley showed that plants could regenerate the bad air making it breathable. Ingenhousz demonstrated that the green parts of plants performed the complete purification of air only under the influence of the light. Spallanzani discovered that plants respire and guessed that the good air (oxygen) originated from the fixed air (carbon dioxide). Finally, Theodore De Saussure showed that plants were able to adsorb carbon dioxide and to release oxygen in a proportional air. All these discoveries benefited of the results coming from investigations of scholars of the so-called "pneumatic chemistry" (Boyle himself, George Ernst Stahl, Joseph Black, Priestley himself, and many more others. But among all the eminent scientists above mentioned stands out the genius of Antoine Laurent Lavoisier, who revolutionised the chemistry of the 18th century ferrying it towards the modern chemistry.

  9. Physiological and molecular alterations in plants exposed to high [CO2] under phosphorus stress.

    Science.gov (United States)

    Pandey, Renu; Zinta, Gaurav; AbdElgawad, Hamada; Ahmad, Altaf; Jain, Vanita; Janssens, Ivan A

    2015-01-01

    Atmospheric [CO2] has increased substantially in recent decades and will continue to do so, whereas the availability of phosphorus (P) is limited and unlikely to increase in the future. P is a non-renewable resource, and it is essential to every form of life. P is a key plant nutrient controlling the responsiveness of photosynthesis to [CO2]. Increases in [CO2] typically results in increased biomass through stimulation of net photosynthesis, and hence enhance the demand for P uptake. However, most soils contain low concentrations of available P. Therefore, low P is one of the major growth-limiting factors for plants in many agricultural and natural ecosystems. The adaptive responses of plants to [CO2] and P availability encompass alterations at morphological, physiological, biochemical and molecular levels. In general low P reduces growth, whereas high [CO2] enhances it particularly in C3 plants. Photosynthetic capacity is often enhanced under high [CO2] with sufficient P supply through modulation of enzyme activities involved in carbon fixation such as ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). However, high [CO2] with low P availability results in enhanced dry matter partitioning towards roots. Alterations in below-ground processes including root morphology, exudation and mycorrhizal association are influenced by [CO2] and P availability. Under high P availability, elevated [CO2] improves the uptake of P from soil. In contrast, under low P availability, high [CO2] mainly improves the efficiency with which plants produce biomass per unit P. At molecular level, the spatio-temporal regulation of genes involved in plant adaptation to low P and high [CO2] has been studied individually in various plant species. Genome-wide expression profiling of high [CO2] grown plants revealed hormonal regulation of biomass accumulation through complex transcriptional networks. Similarly, differential transcriptional regulatory networks are involved in P

  10. ROS and RNS in plant physiology: an overview.

    Science.gov (United States)

    Del Río, Luis A

    2015-05-01

    The production of reactive oxygen species (ROS) is the unavoidable consequence of aerobic life. ROS is a collective term that includes both oxygen radicals, like superoxide (O 2. -) and hydroxyl (·OH) radicals, and other non-radicals such as hydrogen peroxide (H2O2), singlet oxygen ((1)O2 or (1)Δg), etc. In plants, ROS are produced in different cell compartments and are oxidizing species, particularly hydroxyl radicals and singlet oxygen, that can produce serious damage in biological systems (oxidative stress). However, plant cells also have an array of antioxidants which, normally, can scavenge the excess oxidants produced and so avoid deleterious effects on the plant cell bio-molecules. The concept of 'oxidative stress' was re-evaluated in recent years and the term 'oxidative signalling' was created. This means that ROS production, apart from being a potentially harmful process, is also an important component of the signalling network that plants use for their development and for responding to environmental challenges. It is known that ROS play an important role regulating numerous biological processes such as growth, development, response to biotic and environmental stresses, and programmed cell death. The term reactive nitrogen species (RNS) includes radicals like nitric oxide (NO· ) and nitric dioxide (NO2.), as well as non-radicals such as nitrous acid (HNO2) and dinitrogen tetroxide (N2O4), among others. RNS are also produced in plants although the generating systems have still not been fully characterized. Nitric oxide (NO·) has an important function as a key signalling molecule in plant growth, development, and senescence, and RNS, like ROS, also play an important role as signalling molecules in the response to environmental (abiotic) stress. Similarly, NO· is a key mediator, in co-operation with ROS, in the defence response to pathogen attacks in plants. ROS and RNS have been demonstrated to have an increasingly important role in biology and medicine.

  11. Physiological, biochemical, and molecular mechanisms of heat stress tolerance in plants.

    Science.gov (United States)

    Hasanuzzaman, Mirza; Nahar, Kamrun; Alam, Md Mahabub; Roychowdhury, Rajib; Fujita, Masayuki

    2013-05-03

    High temperature (HT) stress is a major environmental stress that limits plant growth, metabolism, and productivity worldwide. Plant growth and development involve numerous biochemical reactions that are sensitive to temperature. Plant responses to HT vary with the degree and duration of HT and the plant type. HT is now a major concern for crop production and approaches for sustaining high yields of crop plants under HT stress are important agricultural goals. Plants possess a number of adaptive, avoidance, or acclimation mechanisms to cope with HT situations. In addition, major tolerance mechanisms that employ ion transporters, proteins, osmoprotectants, antioxidants, and other factors involved in signaling cascades and transcriptional control are activated to offset stress-induced biochemical and physiological alterations. Plant survival under HT stress depends on the ability to perceive the HT stimulus, generate and transmit the signal, and initiate appropriate physiological and biochemical changes. HT-induced gene expression and metabolite synthesis also substantially improve tolerance. The physiological and biochemical responses to heat stress are active research areas, and the molecular approaches are being adopted for developing HT tolerance in plants. This article reviews the recent findings on responses, adaptation, and tolerance to HT at the cellular, organellar, and whole plant levels and describes various approaches being taken to enhance thermotolerance in plants.

  12. Understanding the Biological Roles of Pectins in Plants through Physiological and Functional Characterizations of Plant and Fungal Mutants

    DEFF Research Database (Denmark)

    Stranne, Maria

    The plant cell wall is a dynamic structure and it is involved in regulating a number of physiological features of plants such as physical strength, growth, cell differentiation, intercellular communication, water movement and defense responses. Pectins constitute a major class of plant cell wall...... aspects remain elusive. Studies described in this thesis aimed at gaining new insights into the biological roles of pectin acetylation and arabinosylation in the model plant Arabidopsis thaliana. The thesis consists of four chapters: physiological characterization of cell wall mutants affected in cell...... polysaccharides and consist of backbones rich in galacturonic acids, which are decorated with a range of functional groups including acetyl esters and arabinan sidechains. Although much effort has been made to uncover biological functions of pectins in plants and remarkable progresses have taken place, many...

  13. Influence of plant architecture on maize physiology and yield in the Heilonggang River valley

    Directory of Open Access Journals (Sweden)

    Shoubing Huang

    2017-02-01

    Full Text Available The size and distribution of leaf area determine light interception in a crop canopy and influence overall photosynthesis and yield. Optimized plant architecture renders modern maize hybrids (Zea mays L. more productive, owing to their tolerance of high plant densities. To determine physiological and yield response to maize plant architecture, a field experiment was conducted in 2010 and 2011. With the modern maize hybrid ZD958, three plant architectures, namely triangle, diamond and original plants, were included at two plant densities, 60,000 and 90,000 plants ha−1. Triangle and diamond plants were derived from the original plant by spraying the chemical regulator Jindele (active ingredients, ethephon, and cycocel at different vegetative stages. To assess the effects of plant architecture, a light interception model was developed. Plant height, ear height, leaf size, and leaf orientation of the two regulated plant architectures were significantly reduced or altered compared with those of the original plants. On average across both plant densities and years, the original plants showed higher yield than the triangle and diamond plants, probably because of larger leaf area. The two-year mean grain yield of the original and diamond plants were almost the same at 90,000 plants ha−1 (8714 vs. 8798 kg ha−1. The yield increase (up to 5% of the diamonds plant at high plant densities was a result of increased kernel number per ear, which was likely a consequence of improved plant architecture in the top and middle canopy layers. The optimized light distribution within the canopy can delay leaf senescence, especially for triangle plants. The fraction of incident radiation simulated by the interception model successfully reflected plant architecture traits. Integration of canopy openness is expected to increase the simulation accuracy of the present model. Maize plant architecture with increased tolerance of high densities is probably

  14. Effects of rare earth elements and REE-binding proteins on physiological responses in plants.

    Science.gov (United States)

    Liu, Dongwu; Wang, Xue; Chen, Zhiwei

    2012-02-01

    Rare earth elements (REEs), which include 17 elements in the periodic table, share chemical properties related to a similar external electronic configuration. REEs enriched fertilizers have been used in China since the 1980s. REEs could enter the cell and cell organelles, influence plant growth, and mainly be bound with the biological macromolecules. REE-binding proteins have been found in some plants. In addition, the chlorophyll activities and photosynthetic rate can be regulated by REEs. REEs could promote the protective function of cell membrane and enhance the plant resistance capability to stress produced by environmental factors, and affect the plant physiological mechanism by regulating the Ca²⁺ level in the plant cells. The focus of present review is to describe how REEs and REE-binding proteins participate in the physiological responses in plants.

  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. Development of a portable multi-channel system for plant physiological signal recording

    Directory of Open Access Journals (Sweden)

    Ting Li

    2016-06-01

    Full Text Available Bioelectrical signals can reflect physiological state of organs or tissues in plants and have a significant potential value in research of plant stress tolerance. In order to study the relationship between environment factors and electrical signals in plant, a portable multi-channel physiological signal acquisition system which relevant in plant physiology research was developed. Environment parameters and electrical signals can be measured in different channels by the acquisition system simultaneously and the measurement data will be displayed in an embedded integrated touch screen which is the system processing core. The system was validated to be stable and reliable after the calibration and repeated experiments of recording electrical signals in Helianthus annuus L.

  17. Molecular and physiological mechanisms of plant tolerance to toxic metals

    Science.gov (United States)

    Plants have evolved a myriad of adaptive mechanisms based on a number of genes to deal with the different toxic metals they encounter in the soils worldwide. These genes encode a range of different metal and organic compound transporters and enzyme pathways for the synthesis of metal detoxifying lig...

  18. [Relationships between light and physiological characters of five climbing plants].

    Science.gov (United States)

    Huang, Chenglin; Fu, Songling; Liang, Shuyun; Ji, Yifan

    2004-07-01

    Studies on the photosynthetic and respiratory rates, light utilization efficiencies and light compensations of five climbing plants showed that the diurnal variations of photosynthetic rates presented double peak, the first peak was between 10:00 to 12:00, and the second was between 14:00 to 16:00. The phenomenon of "noon break" was obvious. The diurnal variations of respiration rates also presented double peak, the first peak was between 11:00 to 13:00, and the second was between 14:00 to 17:00. The light compensation point of Hedera nepatensis, H. helix, Parthenocissus tricuspidata, P. quinuefolia and Wisteria sinensis was 5.73, 5.07, 9.96, 6.40 and 18.93 micromol x m(-2) x s(-1), respectively, and the light utilization efficiency of W. sinensis was higher under strong light, P. quinuefolia was the second, but that of H. helix was higher under weak light. The results showed that Wisteria sinensis was a typical heliophytic plant, Parthenocissus tricuspidata and P. quinuefolia were neuter plants, and Hedera nepalensis and H. helix were typical sciophytic plants.

  19. Regulating Intracellular Calcium in Plants: From Molecular Genetics to Physiology

    Energy Technology Data Exchange (ETDEWEB)

    Heven Sze

    2008-06-22

    To grow, develop, adapt, and reproduce, plants have evolved mechanisms to regulate the uptake, translocation and sorting of calcium ions into different cells and subcellular compartments. Yet how plants accomplish this remarkable feat is still poorly understood. The spatial and temporal changes in intracellular [Ca2+] during growth and during responses to hormonal and environmental stimuli indicate that Ca2+ influx and efflux transporters are diverse and tightly regulated in plants. The specific goals were to determine the biological roles of multiple Ca pumps (ECAs) in the model plant Arabidopsis thaliana. We had pioneered the use of K616 yeast strain to functionally express plant Ca pumps, and demonstrated two distinct types of Ca pumps in plants (Sze et al., 2000. Annu Rev Plant Biol. 51,433). ACA2 represented one type that was auto-inhibited by the N-terminal region and stimulated by calmodulin. ECA1 represented another type that was not sensitive to calmodulin and phylogenetically distinct from ACAs. The goal to determine the biological roles of multiple ECA-type Ca pumps in Arabidopsis has been accomplished. Although we demonstrated ECA1 was a Ca pump by functional expression in yeast, the in vivo roles of ECAs was unclear. A few highlights are described. ECA1 and/or ECA4 are Ca/Mn pumps localized to the ER and are highly expressed in all cell types. Using homozygous T-DNA insertional mutants of eca1, we demonstrated that the ER-bound ECA1 supports growth and confers tolerance of plants growing on medium low in Ca or containing toxic levels of Mn. This is the first genetic study to determine the in vivo function of a Ca pump in plants. A phylogenetically distinct ECA3 is also a Ca/Mn pump that is localized to endosome, such as post-Golgi compartments. Although it is expressed at lower levels than ECA1, eca3 mutants are impaired in Ca-dependent root growth and in pollen tube elongation. Increased secretion of wall proteins in mutants suggests that Ca and Mn

  20. Regulating Intracellular Calcium in Plants: From Molecular Genetics to Physiology

    Energy Technology Data Exchange (ETDEWEB)

    Heven Sze

    2008-06-22

    To grow, develop, adapt, and reproduce, plants have evolved mechanisms to regulate the uptake, translocation and sorting of calcium ions into different cells and subcellular compartments. Yet how plants accomplish this remarkable feat is still poorly understood. The spatial and temporal changes in intracellular [Ca2+] during growth and during responses to hormonal and environmental stimuli indicate that Ca2+ influx and efflux transporters are diverse and tightly regulated in plants. The specific goals were to determine the biological roles of multiple Ca pumps (ECAs) in the model plant Arabidopsis thaliana. We had pioneered the use of K616 yeast strain to functionally express plant Ca pumps, and demonstrated two distinct types of Ca pumps in plants (Sze et al., 2000. Annu Rev Plant Biol. 51,433). ACA2 represented one type that was auto-inhibited by the N-terminal region and stimulated by calmodulin. ECA1 represented another type that was not sensitive to calmodulin and phylogenetically distinct from ACAs. The goal to determine the biological roles of multiple ECA-type Ca pumps in Arabidopsis has been accomplished. Although we demonstrated ECA1 was a Ca pump by functional expression in yeast, the in vivo roles of ECAs was unclear. A few highlights are described. ECA1 and/or ECA4 are Ca/Mn pumps localized to the ER and are highly expressed in all cell types. Using homozygous T-DNA insertional mutants of eca1, we demonstrated that the ER-bound ECA1 supports growth and confers tolerance of plants growing on medium low in Ca or containing toxic levels of Mn. This is the first genetic study to determine the in vivo function of a Ca pump in plants. A phylogenetically distinct ECA3 is also a Ca/Mn pump that is localized to endosome, such as post-Golgi compartments. Although it is expressed at lower levels than ECA1, eca3 mutants are impaired in Ca-dependent root growth and in pollen tube elongation. Increased secretion of wall proteins in mutants suggests that Ca and Mn

  1. Dominant role of plant physiology in trend and variability of gross primary productivity in North America

    Science.gov (United States)

    Zhou, Sha; Zhang, Yao; Ciais, Philippe; Xiao, Xiangming; Luo, Yiqi; Caylor, Kelly K.; Huang, Yuefei; Wang, Guangqian

    2017-02-01

    Annual gross primary productivity (GPP) varies considerably due to climate-induced changes in plant phenology and physiology. However, the relative importance of plant phenology and physiology on annual GPP variation is not clear. In this study, a Statistical Model of Integrated Phenology and Physiology (SMIPP) was used to evaluate the relative contributions of maximum daily GPP (GPPmax) and the start and end of growing season (GSstart and GSend) to annual GPP variability, using a regional GPP product in North America during 2000–2014 and GPP data from 24 AmeriFlux sites. Climatic sensitivity of the three indicators was assessed to investigate the climate impacts on plant phenology and physiology. The SMIPP can explain 98% of inter-annual variability of GPP over mid- and high latitudes in North America. The long-term trend and inter-annual variability of GPP are dominated by GPPmax both at the ecosystem and regional scales. During warmer spring and autumn, GSstart is advanced and GSend delayed, respectively. GPPmax responds positively to summer temperature over high latitudes (40–80°N), but negatively in mid-latitudes (25–40°N). This study demonstrates that plant physiology, rather than phenology, plays a dominant role in annual GPP variability, indicating more attention should be paid to physiological change under futher climate change.

  2. Physiological Response of Plants Grown on Porous Ceramic Tubes

    Science.gov (United States)

    Tsao, David; Okos, Martin

    1997-01-01

    This research involves the manipulation of the root-zone water potential for the purposes of discriminating the rate limiting step in the inorganic nutrient uptake mechanism utilized by higher plants. This reaction sequence includes the pathways controlled by the root-zone conditions such as water tension and gradient concentrations. Furthermore, plant based control mechanisms dictated by various protein productions are differentiated as well. For the nutrients limited by the environmental availability, the kinetics were modeled using convection and diffusion equations. Alternatively, for the nutrients dependent upon enzyme manipulations, the uptakes are modeled using Michaelis-Menten kinetics. In order to differentiate between these various mechanistic steps, an experimental apparatus known as the Porous Ceramic Tube - Nutrient Delivery System (PCT-NDS) was used. Manipulation of the applied suction pressure circulating a nutrient solution through this system imposes a change in the matric component of the water potential. This compensates for the different osmotic components of water potential dictated by nutrient concentration. By maintaining this control over the root-zone conditions, the rate limiting steps in the uptake of the essential nutrients into tomato plants (Lycopersicon esculentum cv. Cherry Elite) were differentiated. Results showed that the uptake of some nutrients were mass transfer limited while others were limited by the enzyme kinetics. Each of these were adequately modeled with calculations and discussions of the parameter estimations provided.

  3. Polyploidy in aspen alters plant physiology and drought sensitivity

    Science.gov (United States)

    Greer, B.; Still, C. J.; Brooks, J. R.; Meinzer, F. C.

    2015-12-01

    Polyploids of quaking aspen (Populus tremuloides) may be better suited to dry climatic conditions than diploids. However, the expression of diploid and polyploid functional traits, including water use efficiency, an important component of drought avoidance and tolerance, are not well understood in quaking aspen. In this study diploid and triploid aspen clones' leaf, ramet, and stand functional traits were measured near the Rocky Mountain Biological Laboratory in Gothic, Colorado. The physiology of diploid and triploid aspen, including leaf size, chlorophyll content, stomatal size and density and stomatal conductance, as well as growth rates and carbon isotope discrimination in response to climate (measured in tree rings), were found to be significantly different between ploidy levels. These findings demonstrate different sensitivities of diploid and triploid clones to drought related climate stressors which may impact strategies for aspen forest management and conservation.

  4. Physiological and gene expression responses of sunflower (Helianthus annuus L.) plants differ according to irrigation placement.

    Science.gov (United States)

    Aguado, Ana; Capote, Nieves; Romero, Fernando; Dodd, Ian C; Colmenero-Flores, José M

    2014-10-01

    To investigate effects of soil moisture heterogeneity on plant physiology and gene expression in roots and leaves, three treatments were implemented in sunflower plants growing with roots split between two compartments: a control (C) treatment supplying 100% of plant evapotranspiration, and two treatments receiving 50% of plant evapotranspiration, either evenly distributed to both compartments (deficit irrigation - DI) or unevenly distributed to ensure distinct wet and dry compartments (partial rootzone drying - PRD). Plants receiving the same amount of water responded differently under the two irrigation systems. After 3 days, evapotranspiration was similar in C and DI, but 20% less in PRD, concomitant with decreased leaf water potential (Ψleaf) and increased leaf xylem ABA concentration. Six water-stress responsive genes were highly induced in roots growing in the drying soil compartment of PRD plants, and their expression was best correlated with local soil water content. On the other hand, foliar gene expression differed significantly from that of the root and correlated better with xylem ABA concentration and Ψleaf. While the PRD irrigation strategy triggered stronger physiological and molecular responses, suggesting a more intense and systemic stress reaction due to local dehydration of the dry compartment of PRD plants, the DI strategy resulted in similar water savings without strongly inducing these responses. Correlating physiological and molecular responses in PRD/DI plants may provide insights into the severity and location of water deficits and may enable a better understanding of long-distance signalling mechanisms.

  5. Effects of Planting Date and Plant Density on Physiological Indices, Quantity and Quality Traits of Two Varieties of Marigold (Calendula officinalis L.

    Directory of Open Access Journals (Sweden)

    A Sepehri

    2016-07-01

    physiological indices, quantity and quality traits of two varieties of marigold (Calendula officinalis L., a split-factorial experiment with three replications was carried out in agricultural research station in Arak (latitude: 34o 5' N; longitude: 29o 42' E; 1757 m altitude in 2010 the growing season. Soil was silty-loamy with pH of 7.5 and EC of 0.8 Ds ms-1. The experimental factors included two planting dates (22 April and 2 May, four planting densities (26, 32, 41 and 57 plants/m2 and two varieties (sparse and compact petal. Thinning was performed 20 days after cultivation. Irrigation was carried out in 7 days intervals. For determination of growth indices, ten plants from each plot cut from crown and dried for 48 h in oven at 70°C and then weighted. The plant height, number of flowers per plant, leaf chlorophyll, leaf area index, total dry matter, seed yield, 1000 seed weight, essential oil and grain oil were measured. The extraction of the essential oil of the flower was performed using the Clevenger apparatus by steam distillation (1. Extraction of grain, oil was accomplished according to the soxhelet standard method. The data were analyzed using the statistical analysis system (SAS 9.1 and means were compared using Duncan test at P ≤ 0.05 probability. Results and Discussion Results showed that, planting date and plant density had significant effects on physiological indices, plant height, and number of flowers per plant, 1000 grain weight, chlorophyll index, oil percent and essential oil percentage of marigold. Late planting and decreasing plant density, reduced leaf area index (LAI, total dry weight (TDW and crop growth rate (CGR indices. The compact petal variety showed the highest growth indices compared with spare petal plants. On the other hand, early planting, high plant density and compact petal variety increased the growth and development of plants. The first planting date had higher leaf area index compared to second sowing date. It seems that first sowing

  6. The gravitational plant physiology facility-Description of equipment developed for biological research in spacelab

    Science.gov (United States)

    Heathcote, D. G.; Chapman, D. K.; Brown, A. H.; Lewis, R. F.

    1994-01-01

    In January 1992, the NASA Suttle mission STS 42 carried a facility designed to perform experiments on plant gravi- and photo-tropic responses. This equipment, the Gravitational Plant Physiology Facility (GPPF) was made up of a number of interconnected units mounted within a Spacelab double rack. The details of these units and the plant growth containers designed for use in GPPF are described. The equipment functioned well during the mission and returned a substantial body of time-lapse video data on plant responses to tropistic stimuli under conditions of orbital microgravity. GPPF is maintained by NASA Ames Research Center, and is flight qualifiable for future spacelab missions.

  7. Physiological and phylogenetic analysis of rhizobia isolated from ...

    African Journals Online (AJOL)

    Physiological and phylogenetic analysis of rhizobia isolated from Acacia nilotica L. ... only two isolates were symbiotic and the other three were non- symbiotic. ... Application of effective rhizobia strains as biofertilizers to improve legume ...

  8. Genetic analysis of field and physiological indicators of drought ...

    African Journals Online (AJOL)

    Jane

    2011-10-10

    Oct 10, 2011 ... In order to study the inheritance of field, physiological and metabolite indicators of drought tolerance in wheat .... and the quantum yield was recorded after dark adaptation using a ..... The theory and analysis of diallel crosses.

  9. PHYSIOLOGICAL AND AGROECOLOGICAL ASPECTS OF CADMIUM INTERACTIONS WITH BARLEY PLANTS: AN OVERVIEW

    Directory of Open Access Journals (Sweden)

    A VASSILEV

    2003-07-01

    Full Text Available This work is a review of author’s previous publications, unpublished results as well as available literature on barley responses to Cd contamination. The physiological backgrounds of the acute Cd toxicity in barley plants are briefly described. Some data characterizing the chronic Cd toxicity in barley have been also provided in relation to its possible use for seed production and Cd phytoextraction on Cd-contaminated agricultural soils. Information about the main physiological factors limiting growth of Cd-exposed barley plants and grain yield, seedling quality as well as Cd phytoextraction capacity of barley grown in Cd-contaminated soils is presented.

  10. Nonlinear Analysis of Physiological Time Series

    Institute of Scientific and Technical Information of China (English)

    MENG Qing-fang; PENG Yu-hua; XUE Yu-li; HAN Min

    2007-01-01

    Abstract.The heart rate variability could be explained by a low-dimensional governing mechanism. There has been increasing interest in verifying and understanding the coupling between the respiration and the heart rate. In this paper we use the nonlinear detection method to detect the nonlinear deterministic component in the physiological time series by a single variable series and two variables series respectively, and use the conditional information entropy to analyze the correlation between the heart rate, the respiration and the blood oxygen concentration. The conclusions are that there is the nonlinear deterministic component in the heart rate data and respiration data, and the heart rate and the respiration are two variables originating from the same underlying dynamics.

  11. Modelling of salad plants growth and physiological status in vitamin space greenhouse during lighting regime optimization

    Science.gov (United States)

    Konovalova, Irina; Berkovich, Yuliy A.; Smolyanina, Svetlana; Erokhin, Alexei; Yakovleva, Olga; Lapach, Sergij; Radchenko, Stanislav; Znamenskii, Artem; Tarakanov, Ivan

    2016-07-01

    The efficiency of the photoautotrophic element as part of bio-engineering life-support systems is determined substantially by lighting regime. The artificial light regime optimization complexity results from the wide range of plant physiological functions controlled by light: trophic, informative, biosynthetical, etc. An average photosynthetic photon flux density (PPFD), light spectral composition and pulsed light effects on the crop growth and plant physiological status were studied in the multivariate experiment, including 16 independent experiments in 3 replicates. Chinese cabbage plants (Brassica chinensis L.), cultivar Vesnianka, were grown during 24 days in a climatic chamber under white and red light-emitting diodes (LEDs): photoperiod 24 h, PPFD from 260 to 500 µM/(m ^{2}*s), red light share in the spectrum varying from 33% to 73%, pulsed (pulse period from 30 to 501 µs) and non-pulsed lighting. The regressions of plant photosynthetic and biochemical indexes as well as the crop specific productivity in response to the selected parameters of lighting regime were calculated. Developed models of crop net photosynthesis and dark respiration revealed the most intense gas exchange area corresponding to PPFD level 450 - 500 µM/(m ^{2}*s) with red light share in the spectrum about 60% and the pulse length 30 µs with a pulse period from 300 to 400 µs. Shoot dry weight increased monotonically in response to the increasing PPFD and changed depending on the pulse period under stabilized PPFD level. An increase in ascorbic acid content in the shoot biomass was revealed when increasing red light share in spectrum from 33% to 73%. The lighting regime optimization criterion (Q) was designed for the vitamin space greenhouse as the maximum of a crop yield square on its ascorbic acid concentration, divided by the light energy consumption. The regression model of optimization criterion was constructed based on the experimental data. The analysis of the model made it

  12. Potato type I and II proteinase inhibitors: modulating plant physiology and host resistance.

    Science.gov (United States)

    Turra, David; Lorito, Matteo

    2011-08-01

    Serine protease inhibitors (PIs) are a large and complex group of plant proteins. Members of the potato type I (Pin1) and II (Pin2) proteinase inhibitor families are among the first and most extensively characterized plant PIs. Many insects and phytopathogenic microorganisms use intracellular and extracellular serine proteases playing important roles in pathogenesis. Plants, however, are able to fight these pathogens through the activation of an intricate defence system that leads to the accumulation of various PIs, including Pin1 and Pin2. Several transgenic plants over-expressing members of the Pin1 and Pin2 families have been obtained in the last twenty years and their enhanced defensive capabilities demonstrated against insects, fungi and bacteria. Furthermore, Pin1 and Pin2 genetically engineered plants showed altered regulation of different plant physiological processes (e.g., dehydratation response, programmed cell death, plant growth, trichome density and branching), supporting an endogenous role in various plant species in addition to the well established defensive one. This review summarizes the current knowledge about Pin1 and Pin2 structure, the role of these proteins in plant defence and physiology, and their potential exploitation in biotechnology.

  13. The phytotronist and the phenotype: plant physiology, Big Science, and a Cold War biology of the whole plant.

    Science.gov (United States)

    Munns, David P D

    2015-04-01

    This paper describes how, from the early twentieth century, and especially in the early Cold War era, the plant physiologists considered their discipline ideally suited among all the plant sciences to study and explain biological functions and processes, and ranked their discipline among the dominant forms of the biological sciences. At their apex in the late-1960s, the plant physiologists laid claim to having discovered nothing less than the "basic laws of physiology." This paper unwraps that claim, showing that it emerged from the construction of monumental big science laboratories known as phytotrons that gave control over the growing environment. Control meant that plant physiologists claimed to be able to produce a standard phenotype valid for experimental biology. Invoking the standards of the physical sciences, the plant physiologists heralded basic biological science from the phytotronic produced phenotype. In the context of the Cold War era, the ability to pursue basic science represented the highest pinnacle of standing within the scientific community. More broadly, I suggest that by recovering the history of an underappreciated discipline, plant physiology, and by establishing the centrality of the story of the plant sciences in the history of biology can historians understand the massive changes wrought to biology by the conceptual emergence of the molecular understanding of life, the dominance of the discipline of molecular biology, and the rise of biotechnology in the 1980s. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Study on Effect of Plants in office on Human Physiological/Psychological Responses

    OpenAIRE

    2016-01-01

    Some offices have indoor environmental quality (IEQ) related problems such as space, indoor air quality (IAQ), office workers' thermal comfort, productivity and mental stress. As is well known, some foliage plants have effects of humidity control and VOC removal from indoor air, improvement of productivity and reducing workers' mental stress as well. The objective of this study is to examine the effect of indoor plants on physiological/psychological responses, and to demonstrate the mental he...

  15. Impacts of extreme winter warming events on plant physiology in a sub-Arctic heath community.

    Science.gov (United States)

    Bokhorst, Stef; Bjerke, Jarle W; Davey, Matthew P; Taulavuori, Kari; Taulavuori, Erja; Laine, Kari; Callaghan, Terry V; Phoenix, Gareth K

    2010-10-01

    Insulation provided by snow cover and tolerance of freezing by physiological acclimation allows Arctic plants to survive cold winter temperatures. However, both the protection mechanisms may be lost with winter climate change, especially during extreme winter warming events where loss of snow cover from snow melt results in exposure of plants to warm temperatures and then returning extreme cold in the absence of insulating snow. These events cause considerable damage to Arctic plants, but physiological responses behind such damage remain unknown. Here, we report simulations of extreme winter warming events using infrared heating lamps and soil warming cables in a sub-Arctic heathland. During these events, we measured maximum quantum yield of photosystem II (PSII), photosynthesis, respiration, bud swelling and associated bud carbohydrate changes and lipid peroxidation to identify physiological responses during and after the winter warming events in three dwarf shrub species: Empetrum hermaphroditum, Vaccinium vitis-idaea and Vaccinium myrtillus. Winter warming increased maximum quantum yield of PSII, and photosynthesis was initiated for E. hermaphroditum and V. vitis-idaea. Bud swelling, bud carbohydrate decreases and lipid peroxidation were largest for E. hermaphroditum, whereas V. myrtillus and V. vitis-idaea showed no or less strong responses. Increased physiological activity and bud swelling suggest that sub-Arctic plants can initiate spring-like development in response to a short winter warming event. Lipid peroxidation suggests that plants experience increased winter stress. The observed differences between species in physiological responses are broadly consistent with interspecific differences in damage seen in previous studies, with E. hermaphroditum and V. myrtillus tending to be most sensitive. This suggests that initiation of spring-like development may be a major driver in the damage caused by winter warming events that are predicted to become more

  16. Thermal Power Plant Performance Analysis

    CERN Document Server

    2012-01-01

    The analysis of the reliability and availability of power plants is frequently based on simple indexes that do not take into account the criticality of some failures used for availability analysis. This criticality should be evaluated based on concepts of reliability which consider the effect of a component failure on the performance of the entire plant. System reliability analysis tools provide a root-cause analysis leading to the improvement of the plant maintenance plan.   Taking in view that the power plant performance can be evaluated not only based on  thermodynamic related indexes, such as heat-rate, Thermal Power Plant Performance Analysis focuses on the presentation of reliability-based tools used to define performance of complex systems and introduces the basic concepts of reliability, maintainability and risk analysis aiming at their application as tools for power plant performance improvement, including: ·         selection of critical equipment and components, ·         defini...

  17. The Effects of Salt Stress on Certain Physiological Parameters in Summer Savory (Satureja hortensis L. Plants

    Directory of Open Access Journals (Sweden)

    F.Najafi

    2010-04-01

    Full Text Available Savory plants were treated with different concentrations of NaCl. Plants were grown under controlled environment and harvested after 42 days for measurements of biochemical and physiological parameters. The essential oil of dryed aerial parts of treated plants were isolated and analyzed with GC/MS. The main essential oil compounds were determined as carvacrol (55.37% and g-terpinene (32.92% in control plants. In NaCl treated plants, with increasing NaCl, carvacrol content increased and g-terpinene decreased. In all the plants treated with NaCl, growth parameters, pigments contents and photosynthetic rate were decreased, while, proline and soluble sugars contents increased.Our results indicated that with increasing salinity, carvacrol amount increased which can be considered for medical usages.

  18. Interactive physiological response of potato (Solanum tuberosum L. plants to fungal colonization and Potato virus Y (PVY infection

    Directory of Open Access Journals (Sweden)

    Dominika Thiem

    2014-11-01

    Full Text Available Potato plants can be colonized by various viruses and by symbiotic, saprophytic and pathogenic fungi. However, the significance of interactions of viral infection and fungal colonization is hardly known. This work presents a model experiment in which the influence of three different types of fungal associations on the growth and physiology of the potato variety Pirol was tested individually or in combination with infection by PVY. It was hypothesized that simultaneous viral and fungal infections increase the biotic stress of the host plant, but mutualistic plant-fungal associations can mask the impact of viral infection. In the present study, a symbiotic arbsucular mycorrhizal fungus, Glomus intraradices, significantly stimulated the growth of plants infected with PVY. In contrast, two saprophytic Trichoderma spp. strains either did not influence or even inhibited the growth of PVY-infected plants. Also, inoculation of PVY-infected potato plants with a pathogenic strain of Colletotrichum coccodes did not inhibit the plant growth. Growth of the PVY-free potato plants was not promoted by the symbiotic fungus, whereas T. viride, T. harzianum and C. coccodes had an evident inhibitory effect. The strongest growth inhibition and highest concentration of H2O2, as an indicator of biotic stress, was observed in PVY-free potato plants inoculated with T. harzianum and C. coccodes strains. Surprisingly, ultrastructural analysis of PVY-infected plant roots colonized by G. intraradices showed virus-like structures in the arbuscules. This pointed to the possibility of mycorrhizal-mediated transmission of virus particles and has to be further examined by testing with immunoassays and real transmission to uninfected plants. In conclusion, although mycorrhiza formation might decrease the impact of PVY infection on plants, a possible role of mycorrhizal fungi as virus vectors is discussed.

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

    Science.gov (United States)

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

    2017-07-01

    This study was aimed to identify plant growth-promoting bacterial isolates from soil samples and to investigate their ability to improve plant growth and salt tolerance by analysing phytohormones production and phosphate solubilisation. Among the four tested bacterial isolates (I-2-1, H-1-4, H-2-3, and H-2-5), H-2-5 was able to enhance the growth of Chinese cabbage, radish, tomato, and mustard plants. The isolated bacterium H-2-5 was identified as Bacillus amyloliquefaciens H-2-5 based on 16S rDNA sequence and phylogenetic analysis. The secretion of gibberellins (GA4, GA8, GA9, GA19, and GA20) from B. amyloliquefaciens H-2-5 and their phosphate solubilisation ability may contribute to enhance plant growth. In addition, the H-2-5-mediated mitigation of short term salt stress was tested on soybean plants that were affected by sodium chloride. Abscisic acid (ABA) produced by the H-2-5 bacterium suppressed the NaCl-induced stress effects in soybean by enhancing plant growth and GA4 content, and by lowering the concentration of ABA, salicylic acid, jasmonic acid, and proline. These results suggest that GAs, ABA production, and the phosphate solubilisation capacity of B. amyloliquefaciens H-2-5 are important stimulators that promote plant growth through their interaction and also to improve plant growth by physiological changes in soybean at saline soil.

  20. Detecting plant metabolic responses induced by ground shock using hyperspectral remote sensing and physiological contact measurements

    Energy Technology Data Exchange (ETDEWEB)

    Pickles, W.L.; Cater, G.A.

    1996-12-03

    A series of field experiments were done to determine if ground shock could have induced physiological responses in plants and if the level of the response could be observed. The observation techniques were remote sensing techniques and direct contact physiological measurements developed by Carter for detecting pre-visual plant stress. The remote sensing technique was similar to that used by Pickles to detect what appeared to be ground shock induced plant stress above the 1993 Non Proliferation Experiment`s underground chemical explosion. The experiment was designed to provide direct plant physiological measurements and remote sensing ratio images and from the same plants at the same time. The simultaneous direct and remote sensing measurements were done to establish a ground truth dataset to compare to the results of the hyperspectral remote sensing measurements. In addition, the experiment was designed to include data on what was thought to be the most probable interfering effect, dehydration. The experimental design included investigating the relative magnitude of the shock induced stress effects compared to dehydration effects.

  1. Global plant-responding mechanisms to salt stress: physiological and molecular levels and implications in biotechnology.

    Science.gov (United States)

    Tang, Xiaoli; Mu, Xingmin; Shao, Hongbo; Wang, Hongyan; Brestic, Marian

    2015-01-01

    The increasing seriousness of salinization aggravates the food, population and environmental issues. Ameliorating the salt-resistance of plants especially the crops is the most effective measure to solve the worldwide problem. The salinity can cause damage to plants mainly from two aspects: hyperosmotic and hyperionic stresses leading to the restrain of growth and photosynthesis. To the adverse effects, the plants derive corresponding strategies including: ion regulation and compartmentalization, biosynthesis of compatible solutes, induction of antioxidant enzymes and plant hormones. With the development of molecular biology, our understanding of the molecular and physiology knowledge is becoming clearness. The complex signal transduction underlying the salt resistance is being illuminated brighter and clearer. The SOS pathway is the central of the cell signaling in salt stress. The accumulation of the compatible solutes and the activation of the antioxidant system are the effective measures for plants to enhance the salt resistance. How to make full use of our understanding to improve the output of crops is a huge challenge for us, yet the application of the genetic engineering makes this possible. In this review, we will discuss the influence of the salt stress and the response of the plants in detail expecting to provide a particular account for the plant resistance in molecular, physiological and transgenic fields.

  2. The effect of differential growth rates across plants on spectral predictions of physiological parameters.

    Directory of Open Access Journals (Sweden)

    Tal Rapaport

    Full Text Available Leaves of various ages and positions in a plant's canopy can present distinct physiological, morphological and anatomical characteristics, leading to complexities in selecting a single leaf for spectral representation of an entire plant. A fortiori, as growth rates between canopies differ, spectral-based comparisons across multiple plants--often based on leaves' position but not age--becomes an even more challenging mission. This study explores the effect of differential growth rates on the reflectance variability between leaves of different canopies, and its implication on physiological predictions made by widely-used spectral indices. Two distinct irrigation treatments were applied for one month, in order to trigger the formation of different growth rates between two groups of grapevines. Throughout the experiment, the plants were physiologically and morphologically monitored, while leaves from every part of their canopies were spectrally and histologically sampled. As the control vines were constantly developing new leaves, the water deficit plants were experiencing growth inhibition, resulting in leaves of different age at similar nodal position across the treatments. This modification of the age-position correlation was characterized by a near infrared reflectance difference between younger and older leaves, which was found to be exponentially correlated (R(2 = 0.98 to the age-dependent area of intercellular air spaces within the spongy parenchyma. Overall, the foliage of the control plant became more spectrally variable, creating complications for intra- and inter-treatment leaf-based comparisons. Of the derived indices, the Structure-Insensitive Pigment Index (SIPI was found indifferent to the age-position effect, allowing the treatments to be compared at any nodal position, while a Normalized Difference Vegetation Index (NDVI-based stomatal conductance prediction was substantially affected by differential growth rates. As various

  3. Ecosystem services and plant physiological status during endophyte-assisted phytoremediation of metal contaminated soil.

    Science.gov (United States)

    Burges, Aritz; Epelde, Lur; Blanco, Fernando; Becerril, José M; Garbisu, Carlos

    2017-04-15

    Mining sites shelter a characteristic biodiversity with large potential for the phytoremediation of metal contaminated soils. Endophytic plant growth-promoting bacteria were isolated from two metal-(hyper)accumulator plant species growing in a metal contaminated mine soil. After characterizing their plant growth-promoting traits, consortia of putative endophytes were used to carry out an endophyte-assisted phytoextraction experiment using Noccaea caerulescens and Rumex acetosa (singly and in combination) under controlled conditions. We evaluated the influence of endophyte-inoculated plants on soil physicochemical and microbial properties, as well as plant physiological parameters and metal concentrations. Data interpretation through the grouping of soil properties within a set of ecosystem services was also carried out. When grown together, we observed a 41 and 16% increase in the growth of N. caerulescens and R. acetosa plants, respectively, as well as higher values of Zn phytoextraction and soil microbial biomass and functional diversity. Inoculation of the consortia of putative endophytes did not lead to higher values of plant metal uptake, but it improved the plants' physiological status, by increasing the content of chlorophylls and carotenoids by up to 28 and 36%, respectively, indicating a reduction in the stress level of plants. Endophyte-inoculation also stimulated soil microbial communities: higher values of acid phosphatase activity (related to the phosphate solubilising traits of the endophytes), bacterial and fungal abundance, and structural diversity. The positive effects of plant growth and endophyte inoculation on soil properties were reflected in an enhancement of some ecosystem services (biodiversity, nutrient cycling, water flow regulation, water purification and contamination control).

  4. Is physiological performance a good predictor for fitness? Insights from an invasive plant species.

    Directory of Open Access Journals (Sweden)

    Marco A Molina-Montenegro

    Full Text Available Is physiological performance a suitable proxy of fitness in plants? Although, several studies have been conducted to measure some fitness-related traits and physiological performance, direct assessments are seldom found in the literature. Here, we assessed the physiology-fitness relationship using second-generation individuals of the invasive plant species Taraxacum officinale from 17 localities distributed in five continents. Specifically, we tested if i the maximum quantum yield is a good predictor for seed-output ii whether this physiology-fitness relationship can be modified by environmental heterogeneity, and iii if this relationship has an adaptive consequence for T. officinale individuals from different localities. Overall, we found a significant positive relationship between the maximum quantum yield and fitness for all localities evaluated, but this relationship decreased in T. officinale individuals from localities with greater environmental heterogeneity. Finally, we found that those individuals from localities where environmental conditions are highly seasonal performed better under heterogeneous environmental conditions. Contrarily, under homogeneous controlled conditions, those individuals from localities with low environmental seasonality performed much better. In conclusion, our results suggest that the maximum quantum yield seem to be good predictors for plant fitness. We suggest that rapid measurements, such as those obtained from the maximum quantum yield, could provide a straightforward proxy of individual's fitness in changing environments.

  5. Genetic and physiological analysis of iron biofortification in maize kernels.

    Directory of Open Access Journals (Sweden)

    Mercy G Lung'aho

    Full Text Available BACKGROUND: Maize is a major cereal crop widely consumed in developing countries, which have a high prevalence of iron (Fe deficiency anemia. The major cause of Fe deficiency in these countries is inadequate intake of bioavailable Fe, where poverty is a major factor. Therefore, biofortification of maize by increasing Fe concentration and or bioavailability has great potential to alleviate this deficiency. Maize is also a model system for genomic research and thus allows the opportunity for gene discovery. Here we describe an integrated genetic and physiological analysis of Fe nutrition in maize kernels, to identify loci that influence grain Fe concentration and bioavailability. METHODOLOGY: Quantitative trait locus (QTL analysis was used to dissect grain Fe concentration (FeGC and Fe bioavailability (FeGB from the Intermated B73 × Mo17 (IBM recombinant inbred (RI population. FeGC was determined by ion coupled argon plasma emission spectroscopy (ICP. FeGB was determined by an in vitro digestion/Caco-2 cell line bioassay. CONCLUSIONS: Three modest QTL for FeGC were detected, in spite of high heritability. This suggests that FeGC is controlled by many small QTL, which may make it a challenging trait to improve by marker assisted breeding. Ten QTL for FeGB were identified and explained 54% of the variance observed in samples from a single year/location. Three of the largest FeGB QTL were isolated in sister derived lines and their effect was observed in three subsequent seasons in New York. Single season evaluations were also made at six other sites around North America, suggesting the enhancement of FeGB was not specific to our farm site. FeGB was not correlated with FeGC or phytic acid, suggesting that novel regulators of Fe nutrition are responsible for the differences observed. Our results indicate that iron biofortification of maize grain is achievable using specialized phenotyping tools and conventional plant breeding techniques.

  6. Basic versus applied research: Julius Sachs (1832-1897) and the experimental physiology of plants.

    Science.gov (United States)

    Kutschera, Ulrich

    2015-01-01

    The German biologist Julius Sachs was the first to introduce controlled, accurate, quantitative experimentation into the botanical sciences, and is regarded as the founder of modern plant physiology. His seminal monograph Experimental-Physiologie der Pflanzen (Experimental Physiology of Plants) was published 150 y ago (1865), when Sachs was employed as a lecturer at the Agricultural Academy in Poppelsdorf/Bonn (now part of the University). This book marks the beginning of a new era of basic and applied plant science. In this contribution, I summarize the achievements of Sachs and outline his lasting legacy. In addition, I show that Sachs was one of the first biologists who integrated bacteria, which he considered to be descendants of fungi, into the botanical sciences and discussed their interaction with land plants (degradation of wood etc.). This "plant-microbe-view" of green organisms was extended and elaborated by the laboratory botanist Wilhelm Pfeffer (1845-1920), so that the term "Sachs-Pfeffer-Principle of Experimental Plant Research" appears to be appropriate to characterize this novel way of performing scientific studies on green, photoautotrophic organisms (embryophytes, algae, cyanobacteria).

  7. Plants and men in space - A new field in plant physiology

    Science.gov (United States)

    Andre, M.; Macelroy, R. D.

    1990-01-01

    Results are presented on a comparison of nutritional values of and human psychological responses to algae and of higher plants considered for growth as food on long-term missions in space, together with the technological complexities of growing these plants. The comparison shows the advantages of higher plants, with results suggesting that a high level of material recycling can be obtained. It is noted that the issue of space gravity may be not a major problem for plants because of the possibility that phototropism can provide an alternative sense of direction. Problems of waste recycling can be solved in association with plant cultivation, and a high degree of autonomy of food production can be obtained.

  8. Changes in morpho-physiological attributes of Eucalyptus globulus plants in response to different drought hardening treatments

    OpenAIRE

    Coopman, Rafael E.; Jara,Jorge C; Bravo,Leon A; Sáez,Katia L; Mella,Gloria R; Escobar,Rene

    2008-01-01

    Morpho-physiological attributes exhibited in response to drought hardening at the end of the growing season of Eucalyptus globulus Labill under nursery conditions were studied to evaluate the effect of three drought hardening treatments in morpho-physiological traits used as suitable indicators of drought hardiness, such as, plant growth, root growth potential, plant water relationships and survival. Freezing resistance of drought hardened plants was also studied in order to evaluate cross ha...

  9. Some Physiological Processes Related to Water Use Efficiency of Higher Plants

    Institute of Scientific and Technical Information of China (English)

    GUO Shi-wei; ZHOU Yi; SONG Na; SHEN Qi-rong

    2006-01-01

    Water use efficiency (WUE) of higher plants is of vital importance in the dry-land agricultural ecosystem in terms of the development of water-saving agriculture. Of all the approaches used to improve WUE, the intrinsic water use efficiency (WUET, the ratio of CO2 assimilation rate to transpiration rate) can be a right index, as the variation of WUET is correlated with the physiological and biochemical processes of higher plants. The measurements of leaf gas exchange and carbon isotope discrimination (D13C) are the two ways to detect the variation in WUET. This article reviewed some physiological processes related to WUET, including the relationship between CO2 assimilation and stomatal conductance and WUEr and water absorption. The relationship between WUE and aquaporin and the yield are discussed as well.

  10. Morphological, physiological and plant infectivity characterization of Frankia strains isolated from Casuarina’s nodules

    OpenAIRE

    Patrick Moritz; Kelly Campos Guerra P. de Goes; Souza,José Roberto P de; Letícia Trindade Ataíde; Diva Souza Andrade

    2007-01-01

    Frankia are soil microorganisms that form symbiosis with roots of tree species called actinorhizal plants and are capable of fixing atmospheric N2. This study was carried out to characterize morphologically, physiologically and to assess the nodulation of four Frankia reference strains (HFPCcI3, JCT287, KB5 and F59) and 12 (IPRF) isolated from root nodules of Casuarina plants. All strains (Reference and IPRF) were characterized as Gram-positive and 50% as acid-fast. The Frankia strains produc...

  11. Emerging technologies for non-invasive quantification of physiological oxygen transport in plants.

    Science.gov (United States)

    Chaturvedi, P; Taguchi, M; Burrs, S L; Hauser, B A; Salim, W W A W; Claussen, J C; McLamore, E S

    2013-09-01

    Oxygen plays a critical role in plant metabolism, stress response/signaling, and adaptation to environmental changes (Lambers and Colmer, Plant Soil 274:7-15, 2005; Pitzschke et al., Antioxid Redox Signal 8:1757-1764, 2006; Van Breusegem et al., Plant Sci 161:405-414, 2001). Reactive oxygen species (ROS), by-products of various metabolic pathways in which oxygen is a key molecule, are produced during adaptation responses to environmental stress. While much is known about plant adaptation to stress (e.g., detoxifying enzymes, antioxidant production), the link between ROS metabolism, O2 transport, and stress response mechanisms is unknown. Thus, non-invasive technologies for measuring O2 are critical for understanding the link between physiological O2 transport and ROS signaling. New non-invasive technologies allow real-time measurement of O2 at the single cell and even organelle levels. This review briefly summarizes currently available (i.e., mainstream) technologies for measuring O2 and then introduces emerging technologies for measuring O2. Advanced techniques that provide the ability to non-invasively (i.e., non-destructively) measure O2 are highlighted. In the near future, these non-invasive sensors will facilitate novel experimentation that will allow plant physiologists to ask new hypothesis-driven research questions aimed at improving our understanding of physiological O2 transport.

  12. Physiological and growth response of rice plants (Oryza sativa L.) to Trichoderma spp. inoculants.

    Science.gov (United States)

    Doni, Febri; Isahak, Anizan; Che Mohd Zain, Che Radziah; Wan Yusoff, Wan Mohtar

    2014-01-01

    Trichoderma spp., a known beneficial fungus is reported to have several mechanisms to enhance plant growth. In this study, the effectiveness of seven isolates of Trichoderma spp. to promote growth and increase physiological performance in rice was evaluated experimentally using completely randomized design under greenhouse condition. This study indicated that all the Trichoderma spp. isolates tested were able to increase several rice physiological processes which include net photosynthetic rate, stomatal conductance, transpiration, internal CO2 concentration and water use efficiency. These Trichoderma spp. isolates were also able to enhance rice growth components including plant height, leaf number, tiller number, root length and root fresh weight. Among the Trichoderma spp. isolates, Trichoderma sp. SL2 inoculated rice plants exhibited greater net photosynthetic rate (8.66 μmolCO2 m(-2) s(-1)), internal CO2 concentration (336.97 ppm), water use efficiency (1.15 μmoCO2/mmoH2O), plant height (70.47 cm), tiller number (12), root length (22.5 cm) and root fresh weight (15.21 g) compared to the plants treated with other Trichoderma isolates tested. We conclude that beneficial fungi can be used as a potential growth promoting agent in rice cultivation.

  13. DEAP: A Database for Emotion Analysis Using Physiological Signals

    NARCIS (Netherlands)

    Koelstra, Sander; Mühl, Christian; Soleymani, Mohammad; Lee, Jung Seok; Yazdani, Ashkan; Ebrahimi, Touradj; Pun, Thierry; Nijholt, Anton; Patras, Ioannis

    2012-01-01

    We present a multimodal dataset for the analysis of human affective states. The electroencephalogram (EEG) and peripheral physiological signals of 32 participants were recorded as each watched 40 one-minute long excerpts of music videos. Participants rated each video in terms of the levels of arousa

  14. DEAP: A Database for Emotion Analysis Using Physiological Signals

    NARCIS (Netherlands)

    Koelstra, Sander; Mühl, C.; Soleymani, Mohammad; Lee, Jung Seok; Yazdani, Ashkan; Ebrahimi, Touradj; Pun, Thierry; Nijholt, Antinus; Patras, Ioannis

    2012-01-01

    We present a multimodal dataset for the analysis of human affective states. The electroencephalogram (EEG) and peripheral physiological signals of 32 participants were recorded as each watched 40 one-minute long excerpts of music videos. Participants rated each video in terms of the levels of

  15. Physiological responses of sweet potato (Ipomoea batatas L. plants due to different copper concentrations

    Directory of Open Access Journals (Sweden)

    Cristina Copstein Cuchiara

    2015-12-01

    Full Text Available At low concentrations, Cu is considered as an essential micronutrient for plants and as a constituent and activator of several enzymes. However, when in excess, Cu can negatively affect plant growth and metabolism. Therefore, the aim of this study was to evaluate physiological responses of sweet potato plants at different Cu concentrations by measuring morphological parameters, antioxidant metabolism, stomatal characteristics, and mineral profile. For this purpose, sweet potato plants were grown hydroponically in complete nutrient solution for six days. Then, the plants were transferred to solutions containing different Cu concentrations, 0.041 (control, 0.082, and 0.164 mM, and maintained for nine days. The main effect of increased Cu concentration was observed in the roots. The sweet potato plants grown in 0.082 mM Cu solution showed increased activity of antioxidant enzymes and no changes in growth parameters. However, at a concentration of 0.164 mM, Cu was transported from the roots to the shoots. This concentration altered morpho-anatomical characteristics and activated the antioxidant system because of the stress generated by excess Cu. On the basis of the results, it can be concluded that the sweet potato plants were able to tolerate Cu toxicity until 0.082 mM.

  16. State of the interface between conservation and physiology: a bibliometric analysis.

    Science.gov (United States)

    Lennox, Robert; Cooke, Steven J

    2014-01-01

    Contemporary conservation science benefits from the perspectives of a variety of different disciplines, including a recent synergy with physiology, an interface known as 'conservation physiology'. To evaluate the degree of interaction between conservation and animal/plant physiology, we conducted three bibliometric analyses. We first pursued the use of the term 'conservation physiology' since its first definition in 2006 to determine how frequently it has been used and in which publications. Secondly, we evaluated the occurrence of conservation terms in animal and plant physiology journals, physiological terms in conservation journals, and a combination of terms in ecology journals. Thirdly, we explored trends in a subset of conservation physiology articles published between 2006 and 2012. We identified a surge in the use of the term 'conservation physiology' in 2012, after only a slow increase in usage between 2006 and 2011. Conservation journals tend to have been significantly more active in publishing conservation physiology than animal physiology, plant physiology or ecology journals. However, we found evidence that ecology and animal physiology journals began to incorporate more conservation physiology after 2006, while conservation- and plant physiology-themed journals did not. Among 299 conservation physiology articles that we identified, vertebrate taxa have been over-represented in conservation physiology compared with their relative taxonomic abundance, invertebrate taxa have been under-represented, and plants have been represented in proportion to their relative taxonomic abundance; however, those findings are reasonably consistent with publication trends in conservation biology. Diffuse distribution of conservation physiology papers throughout the literature may have been a barrier to the growth of the subdiscipline when the interface was emerging. The introduction of the focused journal Conservation Physiology in 2013 may address that deficiency

  17. Physiological response and sulfur metabolism of the V. dahliae-infected tomato plants in tomato/potato onion companion cropping

    Science.gov (United States)

    Fu, Xuepeng; Li, Chunxia; Zhou, Xingang; Liu, Shouwei; Wu, Fengzhi

    2016-01-01

    Companion cropping with potato onions (Allium cepa var. agrogatum Don.) can enhance the disease resistance of tomato plants (Solanum lycopersicum) to Verticillium dahliae infection by increasing the expressions of genes related to disease resistance. However, it is not clear how tomato plants physiologically respond to V. dahliae infection and what roles sulfur plays in the disease-resistance. Pot experiments were performed to examine changes in the physiology and sulfur metabolism of tomato roots infected by V. dahliae under the companion cropping (tomato/potato onion). The results showed that the companion cropping increased the content of total phenol, lignin and glutathione and increased the activities of peroxidase, polyphenol oxidase and phenylalanine ammonia lyase in the roots of tomato plants. RNA-seq analysis showed that the expressions of genes involved in sulfur uptake and assimilation, and the formation of sulfur-containing defense compounds (SDCs) were up-regulated in the V. dahlia-infected tomatoes in the companion cropping. In addition, the interactions among tomato, potato onion and V. dahliae induced the expression of the high- affinity sulfate transporter gene in the tomato roots. These results suggest that sulfur may play important roles in tomato disease resistance against V. dahliae. PMID:27808257

  18. Major component analysis of dynamic networks of physiologic organ interactions

    Science.gov (United States)

    Liu, Kang K. L.; Bartsch, Ronny P.; Ma, Qianli D. Y.; Ivanov, Plamen Ch

    2015-09-01

    The human organism is a complex network of interconnected organ systems, where the behavior of one system affects the dynamics of other systems. Identifying and quantifying dynamical networks of diverse physiologic systems under varied conditions is a challenge due to the complexity in the output dynamics of the individual systems and the transient and nonlinear characteristics of their coupling. We introduce a novel computational method based on the concept of time delay stability and major component analysis to investigate how organ systems interact as a network to coordinate their functions. We analyze a large database of continuously recorded multi-channel physiologic signals from healthy young subjects during night-time sleep. We identify a network of dynamic interactions between key physiologic systems in the human organism. Further, we find that each physiologic state is characterized by a distinct network structure with different relative contribution from individual organ systems to the global network dynamics. Specifically, we observe a gradual decrease in the strength of coupling of heart and respiration to the rest of the network with transition from wake to deep sleep, and in contrast, an increased relative contribution to network dynamics from chin and leg muscle tone and eye movement, demonstrating a robust association between network topology and physiologic function.

  19. Chirospecific analysis of plant volatiles

    Energy Technology Data Exchange (ETDEWEB)

    Tkachev, A V [N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2007-10-31

    Characteristic features of the analysis of plant volatiles by enantioselective gas (gas-liquid) chromatography and gas chromatography/mass spectrometry are discussed. The most recent advances in the design of enantioselective stationary phases are surveyed. Examples of the preparation of the most efficient phases based on modified cyclodextrins are given. Current knowledge on the successful analytical resolution of different types of plant volatiles (aliphatic and aromatic compounds and mono-, sesqui- and diterpene derivatives) into optical antipodes is systematically described. Chiral stationary phases used for these purposes, temperature conditions and enantiomer separation factors are summarised. Examples of the enantiomeric resolution of fragrance compounds and components of plant extracts, wines and essential oils are given.

  20. Chirospecific analysis of plant volatiles

    Science.gov (United States)

    Tkachev, A. V.

    2007-10-01

    Characteristic features of the analysis of plant volatiles by enantioselective gas (gas-liquid) chromatography and gas chromatography/mass spectrometry are discussed. The most recent advances in the design of enantioselective stationary phases are surveyed. Examples of the preparation of the most efficient phases based on modified cyclodextrins are given. Current knowledge on the successful analytical resolution of different types of plant volatiles (aliphatic and aromatic compounds and mono-, sesqui- and diterpene derivatives) into optical antipodes is systematically described. Chiral stationary phases used for these purposes, temperature conditions and enantiomer separation factors are summarised. Examples of the enantiomeric resolution of fragrance compounds and components of plant extracts, wines and essential oils are given.

  1. Relationship between Aflatoxin Contamination and Physiological Responses of Corn Plants under Drought and Heat Stress

    Directory of Open Access Journals (Sweden)

    Nacer Bellaloui

    2012-11-01

    Full Text Available Increased aflatoxin contamination in corn by the fungus Aspergillus flavus is associated with frequent periods of drought and heat stress during the reproductive stages of the plants. The objective of this study was to evaluate the relationship between aflatoxin contamination and physiological responses of corn plants under drought and heat stress. The study was conducted in Stoneville, MS, USA under irrigated and non-irrigated conditions. Five commercial hybrids, P31G70, P33F87, P32B34, P31B13 and DKC63-42 and two inbred germplasm lines, PI 639055 and PI 489361, were evaluated. The plants were inoculated with Aspergillus flavus (K-54 at mid-silk stage, and aflatoxin contamination was determined on the kernels at harvest. Several physiological measurements which are indicators of stress response were determined. The results suggested that PI 639055, PI 489361 and hybrid DKC63-42 were more sensitive to drought and high temperature stress in the non-irrigated plots and P31G70 was the most tolerant among all the genotypes. Aflatoxin contamination was the highest in DKC63-42 and PI 489361 but significantly lower in P31G70. However, PI 639055, which is an aflatoxin resistant germplasm, had the lowest aflatoxin contamination, even though it was one of the most stressed genotypes. Possible reasons for these differences are discussed. These results suggested that the physiological responses were associated with the level of aflatoxin contamination in all the genotypes, except PI 639055. These and other physiological responses related to stress may help examine differences among corn genotypes in aflatoxin contamination.

  2. A few aspects of the physiology of flowering in photoperiodic sensitive plants

    Directory of Open Access Journals (Sweden)

    E. G. Groenewald

    2003-09-01

    Full Text Available Three aspects of the physiology of flowering in photoperiodic sensitive plants are discussed. These are the florigen hypothesis, phytochrome and the time measurement mechanism of flowering and genetic-molecular studies involved in flowering. There is evidence that the hypothetical compound, florigen, occurs in plants, but it has never been characterised. There is a family of phytochromes discovered in plants and some of them are involved with the circadian clock and thus with the time measurement mechanism of flowering. The molecular networks that interact to control flowering are being elucidated, by means of genetic-molecular techniques although at an early stage. It has not yet been possible to pinpoint florigen by these methods, but the future looks promising.

  3. Ascending migration of endophytic rhizobia, from roots to leaves, inside rice plants and assessment of benefits to rice growth physiology.

    Science.gov (United States)

    Chi, Feng; Shen, Shi-Hua; Cheng, Hai-Ping; Jing, Yu-Xiang; Yanni, Youssef G; Dazzo, Frank B

    2005-11-01

    Rhizobia, the root-nodule endosymbionts of leguminous plants, also form natural endophytic associations with roots of important cereal plants. Despite its widespread occurrence, much remains unknown about colonization of cereals by rhizobia. We examined the infection, dissemination, and colonization of healthy rice plant tissues by four species of gfp-tagged rhizobia and their influence on the growth physiology of rice. The results indicated a dynamic infection process beginning with surface colonization of the rhizoplane (especially at lateral root emergence), followed by endophytic colonization within roots, and then ascending endophytic migration into the stem base, leaf sheath, and leaves where they developed high populations. In situ CMEIAS image analysis indicated local endophytic population densities reaching as high as 9 x 10(10) rhizobia per cm3 of infected host tissues, whereas plating experiments indicated rapid, transient or persistent growth depending on the rhizobial strain and rice tissue examined. Rice plants inoculated with certain test strains of gfp-tagged rhizobia produced significantly higher root and shoot biomass; increased their photosynthetic rate, stomatal conductance, transpiration velocity, water utilization efficiency, and flag leaf area (considered to possess the highest photosynthetic activity); and accumulated higher levels of indoleacetic acid and gibberellin growth-regulating phytohormones. Considered collectively, the results indicate that this endophytic plant-bacterium association is far more inclusive, invasive, and dynamic than previously thought, including dissemination in both below-ground and above-ground tissues and enhancement of growth physiology by several rhizobial species, therefore heightening its interest and potential value as a biofertilizer strategy for sustainable agriculture to produce the world's most important cereal crops.

  4. Physiological response of natural plants to the change of groundwater level in the lower reaches of Tarim River,Xinjiang

    Institute of Scientific and Technical Information of China (English)

    CHEN Yaning; LI Weihong; CHEN Yapeng; ZHANG Hongfeng; ZHUANG Li

    2004-01-01

    Based on the analysis of the three-year (2000-2002) monitoring data of the four times intermittent stream water conveyance to the lower reaches of Tarim River where the stream flow was dried up for more than 30 years and the measurement of PRO, SOD and POD in plants collected from 24 vegetation plots, it is concluded that the stream water conveyance plays an important role in lifting groundwater level. The groundwater nearby the watercourse was raised from 5~8 m in depth before the stream water conveyance to 2.5~5 m after stream water conveyance. The physiological response of Phragmites communis, Tamarix spp. And Populus euphratica to the change of groundwater is sensitive and represents a grads change obviously. The growth of the plants in the lower reaches of Tarim River is stressed by drought to various degrees. Lengthways, the drought stress exposed to the plants increases with groundwater depth from the upper sections to the lower sections; and breadthwise, the drought stress exposed to the plants is increased with the increase of distance away from the river channel of stream intermittent water releases and of the groundwater depth. Combining the field investigation and the analysis of the plots, it is considered that the stress groundwater depths for the Phragmites communis, Tamarix spp. And Populus euphratica are 3.5 m, 5 m and 4.5 m respectively.

  5. Plant phenotyping: from bean weighing to image analysis.

    Science.gov (United States)

    Walter, Achim; Liebisch, Frank; Hund, Andreas

    2015-01-01

    Plant phenotyping refers to a quantitative description of the plant's anatomical, ontogenetical, physiological and biochemical properties. Today, rapid developments are taking place in the field of non-destructive, image-analysis -based phenotyping that allow for a characterization of plant traits in high-throughput. During the last decade, 'the field of image-based phenotyping has broadened its focus from the initial characterization of single-plant traits in controlled conditions towards 'real-life' applications of robust field techniques in plant plots and canopies. An important component of successful phenotyping approaches is the holistic characterization of plant performance that can be achieved with several methodologies, ranging from multispectral image analyses via thermographical analyses to growth measurements, also taking root phenotypes into account.

  6. The role of silicon in physiology of the medicinal plant (Lonicera japonica L.) under salt stress

    Science.gov (United States)

    Gengmao, Zhao; Shihui, Li; Xing, Sun; Yizhou, Wang; Zipan, Chang

    2015-08-01

    Silicon(Si) is the only element which can enhance the resistance to multiple stresses. However, the role of silicon in medicinal plants under salt stress is not yet understood. This experiment was conducted to study the effects of silicon addition on the growth, osmotic adjustments, photosynthetic characteristics, chloroplast ultrastructure and Chlorogenic acid (CGA) production of Honeysuckle plant (Lonicera japonica L.) under salt-stressed conditions. Salinity exerted an adverse effect on the plant fresh weight and dry weight, whilst 0.5 g L-1 K2SiO3·nH2O addition obviously improved the plant growth. Although Na+ concentration in plant organs was drastically increased with increasing salinity, higher levels of K+/Na+ ratio was obtained after K2SiO3·nH2O addition. Salinity stress induced the destruction of the chloroplast envelope; however, K2SiO3·nH2O addition counteracted the adverse effect by salinity on the structure of the photosynthetic apparatus. K2SiO3·nH2O addition also enhanced the activities of superoxide dismutase and catalase. To sum up, exogenous Si plays a key role in enhancing its resistance to salt stresses in physiological base, thereby improving the growth and CGA production of Honeysuckle plant.

  7. The role of silicon in physiology of the medicinal plant (Lonicera japonica L.) under salt stress.

    Science.gov (United States)

    Gengmao, Zhao; Shihui, Li; Xing, Sun; Yizhou, Wang; Zipan, Chang

    2015-08-03

    Silicon(Si) is the only element which can enhance the resistance to multiple stresses. However, the role of silicon in medicinal plants under salt stress is not yet understood. This experiment was conducted to study the effects of silicon addition on the growth, osmotic adjustments, photosynthetic characteristics, chloroplast ultrastructure and Chlorogenic acid (CGA) production of Honeysuckle plant (Lonicera japonica L.) under salt-stressed conditions. Salinity exerted an adverse effect on the plant fresh weight and dry weight, whilst 0.5 g L(-1) K2SiO3 · nH2O addition obviously improved the plant growth. Although Na(+) concentration in plant organs was drastically increased with increasing salinity, higher levels of K(+)/Na(+) ratio was obtained after K2SiO3 · nH2O addition. Salinity stress induced the destruction of the chloroplast envelope; however, K2SiO3 · nH2O addition counteracted the adverse effect by salinity on the structure of the photosynthetic apparatus. K2SiO3 · nH2O addition also enhanced the activities of superoxide dismutase and catalase. To sum up, exogenous Si plays a key role in enhancing its resistance to salt stresses in physiological base, thereby improving the growth and CGA production of Honeysuckle plant.

  8. Physiological highlights of manganese toxicity symptoms in soybean plants: Mn toxicity responses.

    Science.gov (United States)

    Santos, Elcio Ferreira; Kondo Santini, José Mateus; Paixão, Amanda Pereira; Júnior, Enes Furlani; Lavres, José; Campos, Marcelo; Reis, André Rodrigues Dos

    2017-04-01

    Manganese (Mn) is an essential element for plants; however, high concentrations in certain soil conditions can cause toxicity symptoms in the plant tissue. Here, we describe Mn toxicity symptoms and Mn toxicity responses in soybean plants. Soybean plants exposed to excess Mn showed reductions in the CO2 assimilation rate and stomatal conductance, which in turn resulted in decreased shoot biomass. Furthermore, peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) activity were higher in plants grown with the highest Mn concentration. The Mn doses increased the activity of antioxidant enzymes such as CAT, POD, and SOD. The toxicity symptoms presented by the leaves included hypertrophying of the adaxial epidermis and the formation of necrotic areas with purple-colored veins. Dramatic movement of calcium from the healthy region to the purple-colored necrotic region was observed, as was the exit of potassium from the necrotic area to the healthy region of the tissue. The high activities of POD and SOD in the presence of high Mn compartmented in the roots was the main physiological responses at high Mn uptake by soybean plants. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  9. Functional diversity supports the physiological tolerance hypothesis for plant species richness along climatic gradients

    Science.gov (United States)

    Spasojevic, Marko J.; Grace, James B.; Harrison, Susan; Damschen, Ellen Ingman

    2013-01-01

    1. The physiological tolerance hypothesis proposes that plant species richness is highest in warm and/or wet climates because a wider range of functional strategies can persist under such conditions. Functional diversity metrics, combined with statistical modeling, offer new ways to test whether diversity-environment relationships are consistent with this hypothesis. 2. In a classic study by R. H. Whittaker (1960), herb species richness declined from mesic (cool, moist, northerly) slopes to xeric (hot, dry, southerly) slopes. Building on this dataset, we measured four plant functional traits (plant height, specific leaf area, leaf water content and foliar C:N) and used them to calculate three functional diversity metrics (functional richness, evenness, and dispersion). We then used a structural equation model to ask if ‘functional diversity’ (modeled as the joint responses of richness, evenness, and dispersion) could explain the observed relationship of topographic climate gradients to species richness. We then repeated our model examining the functional diversity of each of the four traits individually. 3. Consistent with the physiological tolerance hypothesis, we found that functional diversity was higher in more favorable climatic conditions (mesic slopes), and that multivariate functional diversity mediated the relationship of the topographic climate gradient to plant species richness. We found similar patterns for models focusing on individual trait functional diversity of leaf water content and foliar C:N. 4. Synthesis. Our results provide trait-based support for the physiological tolerance hypothesis, suggesting that benign climates support more species because they allow for a wider range of functional strategies.

  10. Drought tolerance acquisition in Eucalyptus globulus (Labill.): a research on plant morphology, physiology and proteomics.

    Science.gov (United States)

    Valdés, Ana Elisa; Irar, Sami; Majada, Juan P; Rodríguez, Ana; Fernández, Belén; Pagès, Montserrat

    2013-02-21

    Plants perceiving drought stress activate multiple responses to synchronise developmental and molecular activities aimed at improving survival. In this study we attained a multidisciplinary approach to examine the interplay among plant morphology, physiology and proteomics for understanding the mechanisms underlying the adaptive response to drought stress. The stress-related phenotype, the differential expression of putative members of the LEA family of proteins, the seed proteomic profile, and the endogenous content of free and conjugated abscisic acid (ABA and ABAGE) were analysed in two Eucalyptus globulus provenances with contrasting drought tolerance. Differences in morphology were noticeable, drought-tolerant genotypes displaying smaller seeds with higher desiccation in the mature state and a more developed root system that was not reduced under water stress treatments. From physiological and molecular points of view, the endogenous contents of ABA and ABAGE were also higher in the tolerant provenance, as well as the accumulation of proteins involved in abiotic stress tolerance processes. In addition, evidence of two immunologically-related proteins to the maize RAB17 and RAB28 proteins is first reported in Eucalyptus, showing similarities between species. Our results show that E. globulus displays simultaneous adjustments for acquiring drought tolerance that are expressed at physiological, developmental and molecular levels.

  11. Silicon Regulates Potential Genes Involved in Major Physiological Processes in Plants to Combat Stress

    Directory of Open Access Journals (Sweden)

    Abinaya Manivannan

    2017-08-01

    Full Text Available Silicon (Si, the quasi-essential element occurs as the second most abundant element in the earth's crust. Biological importance of Si in plant kingdom has become inevitable particularly under stressed environment. In general, plants are classified as high, medium, and low silicon accumulators based on the ability of roots to absorb Si. The uptake of Si directly influence the positive effects attributed to the plant but Si supplementation proves to mitigate stress and recover plant growth even in low accumulating plants like tomato. The application of Si in soil as well as soil-less cultivation systems have resulted in the enhancement of quantitative and qualitative traits of plants even under stressed environment. Silicon possesses several mechanisms to regulate the physiological, biochemical, and antioxidant metabolism in plants to combat abiotic and biotic stresses. Nevertheless, very few reports are available on the aspect of Si-mediated molecular regulation of genes with potential role in stress tolerance. The recent advancements in the era of genomics and transcriptomics have opened an avenue for the determination of molecular rationale associated with the Si amendment to the stress alleviation in plants. Therefore, the present endeavor has attempted to describe the recent discoveries related to the regulation of vital genes involved in photosynthesis, transcription regulation, defense, water transport, polyamine synthesis, and housekeeping genes during abiotic and biotic stress alleviation by Si. Furthermore, an overview of Si-mediated modulation of multiple genes involved in stress response pathways such as phenylpropanoid pathway, jasmonic acid pathway, ABA-dependent or independent regulatory pathway have been discussed in this review.

  12. Physiological relevance of plant 2-Cys peroxiredoxin overoxidation level and oligomerization status.

    Science.gov (United States)

    Cerveau, Delphine; Ouahrani, Djelloul; Marok, Mohamed Amine; Blanchard, Laurence; Rey, Pascal

    2016-01-01

    Peroxiredoxins are ubiquitous thioredoxin-dependent peroxidases presumed to display, upon environmental constraints, a chaperone function resulting from a redox-dependent conformational switch. In this work, using biochemical and genetic approaches, we aimed to unravel the factors regulating the redox status and the conformation of the plastidial 2-Cys peroxiredoxin (2-Cys PRX) in plants. In Arabidopsis, we show that in optimal growth conditions, the overoxidation level mainly depends on the availability of thioredoxin-related electron donors, but not on sulfiredoxin, the enzyme reducing the 2-Cys PRX overoxidized form. We also observed that upon various physiological temperature, osmotic and light stress conditions, the overoxidation level and oligomerization status of 2-Cys PRX can moderately vary depending on the constraint type. Further, no major change was noticed regarding protein conformation in water-stressed Arabidopsis, barley and potato plants, whereas species-dependent up- and down-variations in overoxidation were observed. In contrast, both 2-Cys PRX overoxidation and oligomerization were strongly induced during a severe oxidative stress generated by methyl viologen. From these data, revealing that the oligomerization status of plant 2-Cys PRX does not exhibit important variation and is not tightly linked to the protein redox status upon physiologically relevant environmental constraints, the possible in planta functions of 2-Cys PRX are discussed.

  13. Physiological responses of Vetiver plant (Vetiver zizanioides to municipal waste leachate

    Directory of Open Access Journals (Sweden)

    Sasan Mohsenzadeh

    2016-06-01

    Full Text Available Vetiver plant is tolerant to acidity and temperature variations. Has rapid growth for biomass production and has high tolerance to organic and non-organic compounds in municipal waste leachate for example heavy metals. So this plant is good for landfill cultivation. In this study, physiological responses to municipal waste leachate were studied. Statistical design was a randomized complete block and each block treated with different concentrations of latex at levels of zero, 15, 30, 45 and 60 percent compared to the original latex waste. The leachate collected from the Shiraz landfill and brought into the greenhouse. The physiological characterization including leaf area, dry weight, chlorophyll, anthocyanin, proline, soluble sugars and total protein were measured. The result indicated that the dry weight, chlorophyll and anthocyanin decrease with increasing of latex concentration. The leaf area, leaf relative water, soluble sugars and total protein increased with increasing latex concentration. Proline concentration at 15 percent of leachate increased significantly compared to controls, whereas at higher concentrations decreased. According to the results, it is recommended that 45 percent of leachate in a landfill can be used to irrigate Vetiver. This is the maximum concentration of leachate that Vetiver plant can survive as green space. Primary filtration of leachate before using is recommended. If the aim is more growth or perfume application from root, less concentration of leachate is better.

  14. Physiological and biochemical action of SO/sub 2/ on plants

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, H.J.

    1977-06-10

    Needles of spruce and pea plants, exposed to SO/sub 2/, were investigated for their amount of free amino acids. Under the influence of SO/sub 2/, the plants tested synthesize increased amounts of glutamate which stimulates the formation of glutamine and other amino acids of the glutamate family. The enhanced formation of acidic amides may be a N-detoxification process. In spruce needles there is an obvious increase of the amount of the phenolic amino acid tyrosine. The total contents of the free amino acids investigated increased in both the SO/sub 2/-polluted plants. The activities of glutamate dehydrogenase (reductive amination) and glutamine synthetase are stimulated in SO/sub 2/-polluted plants, whereas the glutamic-oxaloacetic- and the glutamic-pyruvate-transaminase are inactivated. The mode of the stimulation of the glutamate dehydrogenase in SO/sub 2/-polluted plants is described. The physiological consequences of the alteration of the composition of the free amino acids are discussed. 17 references, 3 tables.

  15. Effects of foliage plants on human physiological and psychological responses at different temperatures

    Science.gov (United States)

    Jumeno, Desto; Matsumoto, Hiroshi

    2015-02-01

    Escalation of task demands and time pressures tends to make a worker run into work stress, which leads to mental fatigue and depression. The mental fatigue can be reduced when attention capacity is restored. Nature can serve as a source of fascination which can restore the attention capacity. People bring plants indoors so they can experience nature in their workplace. The stress and fatigue are also affected by air temperatures. The increase or decrease of temperatures from the comfort zone may induce the stress and fatigue. The objective of this study is to investigate the intervention of using foliage plants placed inside a building at different air temperature levels. The effects of foliage plants on human stress and fatigue were measured by human physiological responses such as heart rate, amylase level, electroencephalography (EEG), and the secondary task-reaction time. Several different tasks, namely typing, math and logical sequences are included in the investigation of these studies. Fifteen subjects, with the age ranged from 22 to 38 years old have participated in the study using within subject design. From the study, it is revealed that the presence of foliage plants at several temperatures have different effects on meditation, secondary task reaction time and typing accuracy. This study also revealed that the presence of plants on several types of tasks has different effects of attention which are useful for increasing work performance.

  16. Phytotoxicity: An Overview of the Physiological Responses of Plants Exposed to Fungicides

    Directory of Open Access Journals (Sweden)

    Maria Celeste Dias

    2012-01-01

    Full Text Available In the last decades, the use of fungicides in agriculture for fungi diseases control has become crucial. Fungicide research has produced a diverse range of products with novel modes of action. However, the extensive use of these compounds in the agriculture system raises public concern because of the harmful potential of such substances in the environment and human health. Moreover, the phytotoxic effects of some fungicides are already recognized but little is known about the impact of these compounds on the photosynthetic apparatus. This paper presents a comprehensive overview of the literature considering different classes of fungicides and their effects on plant physiology, with particular emphasis on photosynthesis.

  17. Plant sterols, cholesterol precursors and oxysterols: Minute concentrations-Major physiological effects.

    Science.gov (United States)

    Olkkonen, Vesa M; Gylling, Helena; Ikonen, Elina

    2017-05-01

    Non-cholesterol sterols are present in our body at very low concentrations as compared to cholesterol. Small changes in the structure of sterol molecules confer them highly distinct biological activities. The best-known example are steroid hormones derived from cholesterol. During the past decade, our knowledge of also other biomolecules related to or derived from cholesterol, particularly plant sterols, biosynthetic precursors of cholesterol, and oxysterols, has expanded rapidly. In this review article we recapitulate the latest insights into the properties and physiological activities of these non-cholesterol sterols, as well as their importance in disease processes and potential as diagnostic biomarkers. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Physiological stress and performance analysis to karate combat.

    Science.gov (United States)

    Chaabene, Helmi; Hellara, Ilhem; Ghali, Faten B; Franchini, Emerson; Neffati, Fedoua; Tabben, Montassar; Najjar, Mohamed F; Hachana, Younés

    2016-10-01

    This study aimed to evaluate the relationship between physiological, and parameters of performance analysis during karate contest. Nine elite-level karate athletes participated in this study. Saliva sample was collected pre- and post-karate combat. Salivary cortisol (sC) post-combat 2 raised significantly compared to that recorded at pre-combat 1 (Δ%=105.3%; P=0.04; dz=0.78). The largest decrease of the salivary T/C ratio (sR) compared to pre-combat 1 was recorded post-combat 2 (Δ%=-43.5%; P=0.03). Moreover, blood lactate concentration post-combat 1 correlated positively to sCpost-combat 1 (r=0.66; P=0.05) and negatively to both salivary testosterone (sT) (r=-0.76; P=0.01) and sRpost-combat 1 (r=-0.76; P=0.01). There was no significant relationship between hormonal measures and parameters of match analysis. Although under simulated condition, karate combat poses large physiological stress to the karateka. Additionally, physiological strain to karate combat led to a catabolic hormonal response.

  19. Effect of excess iron and copper on physiology of aquatic plant Spirodela polyrrhiza (L.) Schleid.

    Science.gov (United States)

    Xing, Wei; Huang, Wenmin; Liu, Guihua

    2010-04-01

    To elucidate effect of chemical reagents addition on growth of aquatic plants in restoration of aquatic ecosystem, Spirodela polyrrhiza (L.) Schleid was used to evaluate its physiological responses to excess iron (Fe(3+)) and copper (Cu(2+)) in the study. Results showed that accumulation of iron and copper both reached maximum at 100 mg L(-1) iron or copper after 24 h short-term stress, but excess iron and copper caused plants necrosis or death and colonies disintegration as well as roots abscission at excess metal concentrations except for 1 mg L(-1) iron. Significant differences in chlorophyll fluorescence (Fv/Fm) were observed at 1-100 mg L(-1) iron or copper. The synthesis of chlorophyll and protein as well as carbohydrate and the uptake of phosphate and nitrogen were inhibited seriously by excess iron and copper. Proline content decreased with increasing iron or copper concentration, however, MDA content increased with increasing iron or copper concentration.

  20. Aspects of the physiology and biochemistry of some plants existing under the influence of atmosphere pollution

    Energy Technology Data Exchange (ETDEWEB)

    Ionescu, A.; Grou, E.

    1971-01-01

    The vegetation of the Copsa Mica(Romania) zone is often visibly affected by the noxious elements existing in the atmosphere, especially sulfur dioxide. Comparative investigations were undertaken to examine some physiological and biochemical processes in plants from polluted as well as control zones. Water content (total and fractions of free and bound water), stomata condition and hydrogen ion concentration in cellular sap were analyzed; the results of these analyses showed that at the level of all the studied processes, modifications occur, which are sometimes substantial. In laboratory experiments with Pelargonium plants grown in an atmosphere containing sulfur dioxide, a foliar symptomatology was obtained, as well as a chromatogram of free amino acids different to that of controls

  1. Retrospective Analysis of Inflight Exercise Loading and Physiological Outcomes

    Science.gov (United States)

    Ploutz-Snyder, L. L.; Buxton, R. E.; De Witt, J. K.; Guilliams, M. E.; Hanson, A. M.; Peters, B. T.; Pandorf, M. M. Scott; Sibonga, J. D.

    2014-01-01

    Astronauts perform exercise throughout their missions to counter the health declines that occur as a result of long-term exposure to weightlessness. Although all astronauts perform exercise during their missions, the specific prescriptions, and thus the mechanical loading, differs among individuals. For example, inflight ground reaction force data indicate that subject-specific differences exist in foot forces created when exercising on the second-generation treadmill (T2) [1]. The current exercise devices allow astronauts to complete prescriptions at higher intensities, resulting in greater benefits with increased efficiency. Although physiological outcomes have improved, the specific factors related to the increased benefits are unknown. In-flight exercise hardware collect data that allows for exploratory analyses to determine if specific performance factors relate to physiological outcomes. These analyses are vital for understanding which components of exercise are most critical for optimal human health and performance. The relationship between exercise performance variables and physiological changes during flight has yet to be fully investigated. Identifying the critical performance variables that relate to improved physiological outcomes is vital for creating current and future exercise prescriptions to optimize astronaut health. The specific aims of this project are: 1) To quantify the exercise-related mechanical loading experienced by crewmembers on T2 and ARED during their mission on ISS; 2) To explore relationships between exercise loading variables, bone, and muscle health changes during the mission; 3) To determine if specific mechanical loading variables are more critical than others in protecting physiology; 4) To develop methodology for operational use in monitoring accumulated training loads during crew exercise programs. This retrospective analysis, which is currently in progress, is being conducted using data from astronauts that have flown long

  2. Plant nutrition between chemical and physiological limitations: is a sustainable approach possible?

    Directory of Open Access Journals (Sweden)

    Zeno Varanini

    2008-04-01

    Full Text Available The estimate of world population growth and the extent of malnutrition problems due to lack of food or to deficit of specific micronutrients bring to light the importance of plant nutrition in the context of a sustainable development. Beside these aspects, which force to use fertilizers, the topic of nutrient use efficiency of by plants is far from being solved: recent estimates of world cereals productions indicate that use efficiency of nitrogen fertilizers is not higher than 35%. These values are even smaller for phosphorus fertilizers (estimate of use efficiency between 10 and 30%, worsen by the fact that, with the present technology and on the basis of present knowledge, it is expected that the phosphorus reserves used for fertilizer production will be sufficient for less than 100 years. Efficiency problems have also been recently raised concerning the use of synthetic chelates to alleviate deficiency of micronutrients: these compounds have been shown to be extremely mobile along soil profile and to be only partially utilizable by plants. The low uptake efficiency of nutrients from soil is, in one hand, caused by several intrinsic characteristics of the biogeochemical cycle of nutrients, by the other, seems to be limited by biochemical and physiological aspects of nutrient absorption. Only recently, the complexity of these aspects has been apprehended and it has been realized that the programs of breeding had neglected these problematic. In this review aspects related to the acquisition of a macro- (N and a micro- (Fe nutrient, will be discussed. The aim is to show that improvements of mineral nutrient use efficiency can be achieved only through a scientific approach, considering the whole soil-plant system. Particularly emphasis will be put on aspect of molecular physiology relevant to the improvement of nutrient capture efficiency; furthermore, the role of naturally occurring organic molecules in optimizing the nutritional capacity of

  3. Plant nutrition between chemical and physiological limitations: is a sustainable approach possible?

    Directory of Open Access Journals (Sweden)

    Roberto Pinton

    2011-02-01

    Full Text Available The estimate of world population growth and the extent of malnutrition problems due to lack of food or to deficit of specific micronutrients bring to light the importance of plant nutrition in the context of a sustainable development. Beside these aspects, which force to use fertilizers, the topic of nutrient use efficiency of by plants is far from being solved: recent estimates of world cereals productions indicate that use efficiency of nitrogen fertilizers is not higher than 35%. These values are even smaller for phosphorus fertilizers (estimate of use efficiency between 10 and 30%, worsen by the fact that, with the present technology and on the basis of present knowledge, it is expected that the phosphorus reserves used for fertilizer production will be sufficient for less than 100 years. Efficiency problems have also been recently raised concerning the use of synthetic chelates to alleviate deficiency of micronutrients: these compounds have been shown to be extremely mobile along soil profile and to be only partially utilizable by plants. The low uptake efficiency of nutrients from soil is, in one hand, caused by several intrinsic characteristics of the biogeochemical cycle of nutrients, by the other, seems to be limited by biochemical and physiological aspects of nutrient absorption. Only recently, the complexity of these aspects has been apprehended and it has been realized that the programs of breeding had neglected these problematic. In this review aspects related to the acquisition of a macro- (N and a micro- (Fe nutrient, will be discussed. The aim is to show that improvements of mineral nutrient use efficiency can be achieved only through a scientific approach, considering the whole soil-plant system. Particularly emphasis will be put on aspect of molecular physiology relevant to the improvement of nutrient capture efficiency; furthermore, the role of naturally occurring organic molecules in optimizing the nutritional capacity of

  4. NaCl-induced physiological and biochemical adaptative mechanisms in the ornamental Myrtus communis L. plants.

    Science.gov (United States)

    Acosta-Motos, José Ramón; Diaz-Vivancos, Pedro; Álvarez, Sara; Fernández-García, Nieves; Sánchez-Blanco, María Jesús; Hernández, José Antonio

    2015-07-01

    Physiological and biochemical changes in Myrtus communis L. plants after being subjected to different solutions of NaCl (44, and 88 mM) for up to 30 days (Phase I) and after recovery from the salinity period (Phase II) were studied. Myrtle plants showed salinity tolerance by displaying a series of adaptative mechanisms to cope with salt-stress, including controlled ion homeostasis, the increase in root/shoot ratio, the reduction of water potentials and stomatal conductance to limit water loss. In addition, they displayed different strategies to protect the photosynthetic machinery, including limiting toxic ion accumulation in leaves, increase in chlorophyll content, and changes in chlorophyll fluorescence parameters, leaf anatomy and increases in catalase activity. Anatomical modifications in leaves, including a decrease in spongy parenchyma and increased intercellular spaces, allow CO2 diffusion in a situation of reduced stomatal aperture. In spite of all these changes, salinity produced oxidative stress in myrtle plants as monitored by increases in oxidative stress parameter values. The post-recovery period is perceived as a new stress situation, as observed through effects on plant growth and alterations in non-photochemical quenching parameters and lipid peroxidation values.

  5. Mechanisms and effective control of physiological browning phenomena in plant cell cultures.

    Science.gov (United States)

    Dong, Yan-Shan; Fu, Chun-Hua; Su, Peng; Xu, Xiang-Ping; Yuan, Jie; Wang, Sheng; Zhang, Meng; Zhao, Chun-Fang; Yu, Long-Jiang

    2016-01-01

    Browning phenomena are ubiquitous in plant cell cultures that severely hamper scientific research and widespread application of plant cell cultures. Up to now, this problem still has not been well controlled due to the unclear browning mechanisms in plant cell cultures. In this paper, the mechanisms were investigated using two typical materials with severe browning phenomena, Taxus chinensis and Glycyrrhiza inflata cells. Our results illustrated that the browning is attributed to a physiological enzymatic reaction, and phenolic biosynthesis regulated by sugar plays a decisive role in the browning. Furthermore, to confirm the specific compounds which participate in the enzymatic browning reaction, transcriptional profile and metabolites of T. chinensis cells, and UV scanning and high-performance liquid chromatography-mass spectrometry (HPLC-MS) profile of the browning compounds extracted from the brown-turned medium were analyzed, flavonoids derived from phenylpropanoid pathway were found to be the main compounds, and myricetin and quercetin were deduced to be the main substrates of the browning reaction. Inhibition of flavonoid biosynthesis can prevent the browning occurrence, and the browning is effectively controlled via blocking flavonoid biosynthesis by gibberellic acid (GA3 ) as an inhibitor, which further confirms that flavonoids mainly contribute to the browning. On the basis above, a model elucidating enzymatic browning mechanisms in plant cell cultures was put forward, and effective control approaches were presented.

  6. Effects of Three Fire-Suppressant Foams on the Germination and Physiological Responses of Plants

    Science.gov (United States)

    Song, Uhram; Mun, Saeromi; Waldman, Bruce; Lee, Eun Ju

    2014-10-01

    Suppressant foams used to fight forest fires may leave residual effects on surviving biota that managers need to consider prior to using them. We examined how three fire-suppressant foams (FSFs) (Forexpan S, Phos-Chek-WD881, and Silv-ex) affected seed germination and physiological responses of three plant species. Exposure to FSFs, whether in diluted concentrations or those typical in the field, reduced final germination percentages of seeds grown in petri dishes and within growth chambers. However, the FSFs did not cause total germination failure in any treatment. Inhibition of germination increased with longer exposure times, but only to diluted FSF solutions. Unlike in the laboratory experiments, none of the three FSFs affected seedling emergence when tested in field conditions. Further, we found no evidence of long-term phytotoxic effects on antioxidant enzyme activity nor chlorophyll content of the plant saplings. Therefore, although the three FSFs showed evidence of phytotoxicity to plants in laboratory tests, their actual impact on terrestrial ecosystems may be minimal. We suggest that the benefits of using these FSFs to protect plants in threatened forest ecosystems outweigh their minor risks.

  7. Physiological, biochemical and molecular responses of the potato (Solanum tuberosum L.) plant to moderately elevated temperature.

    Science.gov (United States)

    Hancock, Robert D; Morris, Wayne L; Ducreux, Laurence J M; Morris, Jenny A; Usman, Muhammad; Verrall, Susan R; Fuller, John; Simpson, Craig G; Zhang, Runxuan; Hedley, Pete E; Taylor, Mark A

    2014-02-01

    Although significant work has been undertaken regarding the response of model and crop plants to heat shock during the acclimatory phase, few studies have examined the steady-state response to the mild heat stress encountered in temperate agriculture. In the present work, we therefore exposed tuberizing potato plants to mildly elevated temperatures (30/20 °C, day/night) for up to 5 weeks and compared tuber yield, physiological and biochemical responses, and leaf and tuber metabolomes and transcriptomes with plants grown under optimal conditions (22/16 °C). Growth at elevated temperature reduced tuber yield despite an increase in net foliar photosynthesis. This was associated with major shifts in leaf and tuber metabolite profiles, a significant decrease in leaf glutathione redox state and decreased starch synthesis in tubers. Furthermore, growth at elevated temperature had a profound impact on leaf and tuber transcript expression with large numbers of transcripts displaying a rhythmic oscillation at the higher growth temperature. RT-PCR revealed perturbation in the expression of circadian clock transcripts including StSP6A, previously identified as a tuberization signal. Our data indicate that potato plants grown at moderately elevated temperatures do not exhibit classic symptoms of abiotic stress but that tuber development responds via a diversity of biochemical and molecular signals.

  8. The impact of Ni on the physiology of a Mediterranean Ni-hyperaccumulating plant.

    Science.gov (United States)

    Roccotiello, Enrica; Serrano, Helena Cristina; Mariotti, Mauro Giorgio; Branquinho, Cristina

    2016-06-01

    High nickel (Ni) levels exert toxic effects on plant growth and plant water content, thus affecting photosynthesis. In a pot experiment, we investigated the effect of the Ni concentration on the physiological characteristics of the Ni hyperaccumulator Alyssoides utriculata when grown on a vermiculite substrate in the presence of different external Ni concentrations (0-500 mg Ni L(-1)). The results showed that the Ni concentration was higher in leaves than in roots, as evidenced by a translocation factor = 3 and a bioconcentration factor = 10. At the highest concentration tested (500 mg Ni L(-1)), A. utriculata accumulated 1100 mg Ni per kilogram in its leaves, without an effects on its biomass. Plant water content increased significantly with Ni accumulation. Ni treatment did not, or only slightly, affected chlorophyll fluorescence parameters. The photosynthetic efficiency (FV/FM) of A. utriculata was stable between Ni treatments (always ≥ 0.8) and the photosynthetic performance of the plant under Ni stress remained high (performance index = 1.5). These findings support that A. utriculata has several mechanisms to avoid severe damage to its photosynthetic apparatus, confirming the tolerance of this species to Ni under hyperaccumulation.

  9. Key physiological properties contributing to rhizosphere adaptation and plant growth promotion abilities of Azospirillum brasilense.

    Science.gov (United States)

    Fibach-Paldi, Sharon; Burdman, Saul; Okon, Yaacov

    2012-01-01

    Azospirillum brasilense is a plant growth promoting rhizobacterium (PGPR) that is being increasingly used in agriculture in a commercial scale. Recent research has elucidated key properties of A. brasilense that contribute to its ability to adapt to the rhizosphere habitat and to promote plant growth. They include synthesis of the auxin indole-3-acetic acid, nitric oxide, carotenoids, and a range of cell surface components as well as the ability to undergo phenotypic variation. Storage and utilization of polybetahydroxyalkanoate polymers are important for the shelf life of the bacteria in production of inoculants, products containing bacterial cells in a suitable carrier for agricultural use. Azospirillum brasilense is able to fix nitrogen, but despite some controversy, as judging from most systems evaluated so far, contribution of fixed nitrogen by this bacterium does not seem to play a major role in plant growth promotion. In this review, we focus on recent advances in the understanding of physiological properties of A. brasilense that are important for rhizosphere performance and successful interactions with plant roots.

  10. PPDB: A Tool for Investigation of Plants Physiology Based on Gene Ontology.

    Science.gov (United States)

    Sharma, Ajay Shiv; Gupta, Hari Om; Prasad, Rajendra

    2015-09-01

    Representing the way forward, from functional genomics and its ontology to functional understanding and physiological model, in a computationally tractable fashion is one of the ongoing challenges faced by computational biology. To tackle the standpoint, we herein feature the applications of contemporary database management to the development of PPDB, a searching and browsing tool for the Plants Physiology Database that is based upon the mining of a large amount of gene ontology data currently available. The working principles and search options associated with the PPDB are publicly available and freely accessible online ( http://www.iitr.ac.in/ajayshiv/ ) through a user-friendly environment generated by means of Drupal-6.24. By knowing that genes are expressed in temporally and spatially characteristic patterns and that their functionally distinct products often reside in specific cellular compartments and may be part of one or more multicomponent complexes, this sort of work is intended to be relevant for investigating the functional relationships of gene products at a system level and, thus, helps us approach to the full physiology.

  11. Mathematical literacy in Plant Physiology undergraduates: results of interventions aimed at improving students' performance

    Science.gov (United States)

    Vila, Francisca; Sanz, Amparo

    2013-09-01

    The importance of mathematical literacy in any scientific career is widely recognized. However, various studies report lack of numeracy and mathematical literacy in students from various countries. In the present work, we present a detailed study of the mathematical literacy of Spanish undergraduate students of Biology enrolled in a Plant Physiology course. We have performed individual analyses of results obtained during the period 2000-2011, for questions in the examinations requiring and not requiring mathematical skills. Additionally, we present the outcome of two interventions introduced with the aim of helping students improve their prospects for success in the course. Our results confirm previous research showing students' deficiencies in mathematical skills. However, the scores obtained for mathematical questions in the examinations are good predictors of the final grades attained in Plant Physiology, as there are strong correlations at the individual level between results for questions requiring and not requiring mathematical skills. The introduction of a laboratory session devoted to strengthening the application of students' previously acquired mathematical knowledge did not change significantly the results obtained for mathematical questions. Since mathematical abilities of students entering university have declined in recent years, this intervention may have helped to maintain students' performance to a level comparable to that of previous years. The outcome of self-assessment online tests indicates that although Mathematics anxiety is lower than during examinations, the poor results obtained for questions requiring mathematical skills are, at least in part, due to a lack of self-efficacy.

  12. Improving intercropping: a synthesis of research in agronomy, plant physiology and ecology.

    Science.gov (United States)

    Brooker, Rob W; Bennett, Alison E; Cong, Wen-Feng; Daniell, Tim J; George, Timothy S; Hallett, Paul D; Hawes, Cathy; Iannetta, Pietro P M; Jones, Hamlyn G; Karley, Alison J; Li, Long; McKenzie, Blair M; Pakeman, Robin J; Paterson, Eric; Schöb, Christian; Shen, Jianbo; Squire, Geoff; Watson, Christine A; Zhang, Chaochun; Zhang, Fusuo; Zhang, Junling; White, Philip J

    2015-04-01

    Intercropping is a farming practice involving two or more crop species, or genotypes, growing together and coexisting for a time. On the fringes of modern intensive agriculture, intercropping is important in many subsistence or low-input/resource-limited agricultural systems. By allowing genuine yield gains without increased inputs, or greater stability of yield with decreased inputs, intercropping could be one route to delivering ‘sustainable intensification’. We discuss how recent knowledge from agronomy, plant physiology and ecology can be combined with the aim of improving intercropping systems. Recent advances in agronomy and plant physiology include better understanding of the mechanisms of interactions between crop genotypes and species – for example, enhanced resource availability through niche complementarity. Ecological advances include better understanding of the context-dependency of interactions, the mechanisms behind disease and pest avoidance, the links between above- and below-ground systems, and the role of microtopographic variation in coexistence. This improved understanding can guide approaches for improving intercropping systems, including breeding crops for intercropping. Although such advances can help to improve intercropping systems, we suggest that other topics also need addressing. These include better assessment of the wider benefits of intercropping in terms of multiple ecosystem services, collaboration with agricultural engineering, and more effective interdisciplinary research.

  13. Simple and robust determination of the activity signature of key carbohydrate metabolism enzymes for physiological phenotyping in model and crop plants

    DEFF Research Database (Denmark)

    Jammer, Alexandra; Gasperl, Anna; Luschin-Ebengreuth, Nora;

    2015-01-01

    The analysis of physiological parameters is important to understand the link between plant phenotypes and their genetic bases, and therefore is needed as an important element in the analysis of model and crop plants. The activities of enzymes involved in primary carbohydrate metabolism have been...... shown to be strongly associated with growth performance, crop yield, and quality, as well as stress responses. A simple, fast, and cost-effective method to determine activities for 13 key enzymes involved in carbohydrate metabolism has been established, mainly based on coupled spectrophotometric kinetic...

  14. Conceptual analysis of Physiology of vision in Ayurveda.

    Science.gov (United States)

    Balakrishnan, Praveen; Ashwini, M J

    2014-07-01

    The process by which the world outside is seen is termed as visual process or physiology of vision. There are three phases in this visual process: phase of refraction of light, phase of conversion of light energy into electrical impulse and finally peripheral and central neurophysiology. With the advent of modern instruments step by step biochemical changes occurring at each level of the visual process has been deciphered. Many investigations have emerged to track these changes and helping to diagnose the exact nature of the disease. Ayurveda has described this physiology of vision based on the functions of vata and pitta. Philosophical textbook of ayurveda, Tarka Sangraha, gives certain basics facts of visual process. This article discusses the second and third phase of visual process. Step by step analysis of the visual process through the spectacles of ayurveda amalgamated with the basics of philosophy from Tarka Sangraha has been analyzed critically to generate a concrete idea regarding the physiology and hence thereby interpret the pathology on the grounds of ayurveda based on the investigative reports.

  15. Functional analysis of spontaneous cell movement under different physiological conditions.

    Directory of Open Access Journals (Sweden)

    Hiroaki Takagi

    Full Text Available Cells can show not only spontaneous movement but also tactic responses to environmental signals. Since the former can be regarded as the basis to realize the latter, playing essential roles in various cellular functions, it is important to investigate spontaneous movement quantitatively at different physiological conditions in relation to a cell's physiological functions. For that purpose, we observed a series of spontaneous movements by Dictyostelium cells at different developmental periods by using a single cell tracking system. Using statistical analysis of these traced data, we found that cells showed complex dynamics with anomalous diffusion and that their velocity distribution had power-law tails in all conditions. Furthermore, as development proceeded, average velocity and persistency of the movement increased and as too did the exponential behavior in the velocity distribution. Based on these results, we succeeded in applying a generalized Langevin model to the experimental data. With this model, we discuss the relation of spontaneous cell movement to cellular physiological function and its relevance to behavioral strategies for cell survival.

  16. Conceptual analysis of Physiology of vision in Ayurveda

    Directory of Open Access Journals (Sweden)

    Praveen Balakrishnan

    2014-01-01

    Full Text Available The process by which the world outside is seen is termed as visual process or physiology of vision. There are three phases in this visual process: phase of refraction of light, phase of conversion of light energy into electrical impulse and finally peripheral and central neurophysiology. With the advent of modern instruments step by step biochemical changes occurring at each level of the visual process has been deciphered. Many investigations have emerged to track these changes and helping to diagnose the exact nature of the disease. Ayurveda has described this physiology of vision based on the functions of vata and pitta. Philosophical textbook of ayurveda, Tarka Sangraha, gives certain basics facts of visual process. This article discusses the second and third phase of visual process. Step by step analysis of the visual process through the spectacles of ayurveda amalgamated with the basics of philosophy from Tarka Sangraha has been analyzed critically to generate a concrete idea regarding the physiology and hence thereby interpret the pathology on the grounds of ayurveda based on the investigative reports.

  17. Phytochemical analysis of selected medicinal plants | Hussain ...

    African Journals Online (AJOL)

    Phytochemical analysis of selected medicinal plants. ... African Journal of Biotechnology ... Abstract. Four medicinal plants including Ranunculus arvensis, Equisetum ravens, Carathamus lanatus and Fagonia critica were used for the study.

  18. Research with radiation and radioisotopes to better understand plant physiology and agricultural consequences of radioactive contamination from the Fukushima Daiichi nuclear accident.

    Science.gov (United States)

    Nakanishi, Tomoko M

    2017-01-01

    Research carried out by me and my group over the last almost four decades are summarized here. The main emphasis of my work was and continues to be on plant physiology using radiation and radioisotopes. Plants live on water and inorganic elements. In the case of water, we developed neutron imaging methods and produced (15)O-labeled water (half-life 2 min) and applied them to understand water circulation pattern in the plant. In the case of elements, we developed neutron activation analysis methods to analyze a large number of plant tissues to follow element specific distribution. Then, we developed real-time imaging system using conventional radioisotopes for the macroscopic and microscopic observation of element movement. After the accident in Fukushima Daiichi nuclear power plant, we, the academic staff of Graduate School, have been studying agricultural effects of radioactive fallout; the main results are summarized in two books published by Springer.

  19. Effect of low dosage biochar amendment on plant physiology parameters of sunflowers

    Science.gov (United States)

    María De la Rosa, José; Paneque, Marina; Franco-Navarro, Juan D.; Colmenero-Flores, José Manuel; Knicker, Heike

    2017-04-01

    Four different biochars were used as organic ameliorants in a typical agricultural soil of the Mediterranean region a (Calcic Cambisol). This field study was performed with plants of sunflower (Helianthus annuus L.) at the experimental station "La Hampa", located in the Guadalquivir river valley (SW Spain). The soil was amended with doses equivalent to 1.5 and 15 t ha-1 of the four biochars in two independent plantations. In addition, un-amended plots were prepared for comparison purposes 1. This study showed that the amendment with 1.5 t biochar ha-1 did not modify significantly soil properties, or the agronomic productivity of sunflowers. However, in spite of this low dose of biochar, positive effects on plant physiology were observed. The efficiency of Photosystem-II (quantum yield (QYPSII)), is a stress marker, related to the water status of the plant, and is reduced under drought stress. The QYPSII values of the plants grown with 1.5 t biochar ha-1 were higher than in the control and ranged between 72 and 77%. Values between 70 and 80% correspond to non-stressed (well-watered) sunflower plants. Biochar reduced stomatal conductance (gs, leaf transpiration) in both treatments. Therefore, the dependence of agronomic productivity on biochar dose was not observed, since both doses resulted in similar gs reductions. In C3 plants, such as sunflower, an increase of leaf area (LA) is usually associated to a decrease of gs caused by a reduction of stomatal frequency and increases the water use efficiency and drought tolerance 2. However, here no clear correlation could be established between biochar-induced LA stimulation and gs response after application of biochar. Thus, gs reduction was evident but not a consequence of LA increase. We hypothesize that biochar addition to soils alters anatomical and/or physiological parameters of the plants that in turn reduces stomatal conductance and increases water use efficiency of sunflower plants. After the last rain, increasing

  20. Crop management as a driving force of plant growth promoting rhizobacteria physiology.

    Science.gov (United States)

    Melo, Juliana; Carolino, Manuela; Carvalho, Luís; Correia, Patrícia; Tenreiro, Rogério; Chaves, Sandra; Meleiro, Ana I; de Souza, Sávio B; Dias, Teresa; Cruz, Cristina; Ramos, Alessandro C

    2016-01-01

    Crop management systems influence plant productivity and nutrient use efficiency, as well as plant growth-promoting rhizobacteria (PGPR), which are known to influence the growth of plants via phytohormone production, phosphate solubilization, nitrogen (N) fixation and antimicrobial activity. The objective of this study was to compare the influence of two crop management system on microbial PGPR features. PGPR isolated from the rhizospheres of Carica papaya L. grown under two distinct management systems (conventional and organic) were identified and characterized. The 12 strains most efficient in solubilizing inorganic phosphate belonged to the genera Burkholderia, Klebsiella, and Leclercia. N fixation was observed in the strains B. vietnamiensis from the conventional farming system and B. vietnamiensis, B. cepacia and Leclercia sp. from the organic farming system. The B. vietnamiensis, B. cepacia, Klebsiella sp. and Klebsiella sp. isolates showed antifungal activity, while Leclercia sp. did not. The strains B. vietnamiensis and Enterobcter sp. (isolated from the conventional farming system) and Klebsiella sp. (isolated from the organic farming system) were efficient at solubilizing phosphate, producing phytohormones and siderophores, and inhibiting the mycelial growth of various phytopathogenic fungi (Botrytis cinerea, Pestalotia sp., Alternaria sp., Phoma sp., Fusarium culmorum, Geotrichum candidum). Physiological differences between the isolates from the two crop management regimes were distinguishable after 10 years of distinct management.

  1. Eco-physiological Effects of Atmospheric Ozone and Polycyclic Aromatic Hydrocarbons (PAHs) on Plants

    Science.gov (United States)

    Bandai, S.; Sakugawa, H. H.

    2012-12-01

    [Introduction] Tropospheric ozone is one of most concerned air pollutant, by causing damage to trees and crops. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants found in various environmental compartments. Photo-induced toxicity of PAHs can be driven from formation of intracellular single oxygen and other reactive oxygen intermediates (ROI) leading to biological damages.(1) In the present study, we measured photosynthesis rate and other variables to investigate the effects of ozone and PAHs on the eco-physiological status of plants such as eggplant, common bean and strawberry. Plants treated with the single or combined air pollutants are expected to exhibit altered physiological, morphological and possibly growth changes. [Materials and Methods] We performed three exposure experiments. Exp.1. Eggplant (Solanum melongena) seedlings, were placed in the open-top chambers (n=6 plants/treatment). Treatment system was ozone (O)(120ppb), phenanthrene (P)(10μM), O+P, fluoranthene (F)(10μM), O+F, mannitol (M)(1mM) and the control (Milli-Q water)(C). P, F and M were sprayed three times weekly on the foliage part of eggplant. Average volume sprayed per seedling was 50mL. The treatment period was 30days and [AOT 40 (Accumulated exposure over a threshold of 40 ppb)]=28.8 ppmh. Exp.2, Common bean (Phaseolus vulgaris L.) seedlings were used (n=5 plants/treatment). The treatment system was the same as Exp.1. The treatment period was 40days and [AOT 40]=38.4ppmh. Exp.3. Strawberry (Fragaria L.) seedlings were used (n=5 plants/treatment). Treatment system was O (120ppb), F(10μM), O+F, F+M, O+M and C. The treatment period was 90days and [AOT 40]=86.4ppmh. Ecophysiological variables examined were photosynthesis rate measured at saturated irradiance (Amax), stomatal conductance to water vapour (gs), internal CO2 concentration (Ci), photochemical efficiency of PS2 in the dark (Fv/Fm), chlorophyll contents, visual symptom assessment and elemental composition in the

  2. Desiccation tolerance mechanism in resurrection fern-ally Selaginella tamariscina revealed by physiological and proteomic analysis.

    Science.gov (United States)

    Wang, Xiaonan; Chen, Sixue; Zhang, Heng; Shi, Lei; Cao, Fenglin; Guo, Lihai; Xie, Yongming; Wang, Tai; Yan, Xiufeng; Dai, Shaojun

    2010-12-03

    Drought is one of the most severe limitations to plant growth and productivity. Resurrection plants have evolved a unique capability to tolerate desiccation in vegetative tissues. Fern-ally Selaginella tamariscina (Beauv.) is one of the most primitive vascular resurrection plants, which can survive a desiccated state and recover when water becomes available. To better understand the mechanism of desiccation tolerance, we have applied physiological and proteomic analysis. Samples of S. tamariscina were water-deprived for up to seven days followed by 12 h of rewatering. Our results showed that endogenous abscisic acid (ABA) increased to regulate dehydration-responsive genes/proteins and physiological processes. In the course of dehydration, the contents of osmolytes represented by soluble sugars and proline were increased to maintain cell structure integrity. The activities of four antioxidant enzymes (superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and glutathione reductase (GR)) also increased. In contrast, both the rate of photosynthesis and the chlorophyll content decreased, and plasma membrane integrity was lost. We identified 138 desiccation-responsive two-dimensional electrophoresis (2-DE) spots, representing 103 unique proteins. Hierarchical clustering analysis revealed that 83% of the proteins were down-regulated upon dehydration. They were mainly involved in photosynthesis, carbohydrate and energy metabolism, stress and defense, protein metabolism, signaling, membrane/transport, cell structure, and cell division. The dynamic expression changes of the desiccation-responsive proteins provide strong evidence that cell structure modification, photosynthesis reduction, antioxidant system activation, and protein post-transcriptional/translational modifications are essential to the poikilochlorophyllous fern-ally S. tamariscina in response to dehydration. In addition, our comparative analysis of dehydration-responsive proteins in vegetative tissues

  3. A LOV protein modulates the physiological attributes of Xanthomonas axonopodis pv. citri relevant for host plant colonization.

    Directory of Open Access Journals (Sweden)

    Ivana Kraiselburd

    Full Text Available Recent studies have demonstrated that an appropriate light environment is required for the establishment of efficient vegetal resistance responses in several plant-pathogen interactions. The photoreceptors implicated in such responses are mainly those belonging to the phytochrome family. Data obtained from bacterial genome sequences revealed the presence of photosensory proteins of the BLUF (Blue Light sensing Using FAD, LOV (Light, Oxygen, Voltage and phytochrome families with no known functions. Xanthomonas axonopodis pv. citri is a Gram-negative bacterium responsible for citrus canker. The in silico analysis of the X. axonopodis pv. citri genome sequence revealed the presence of a gene encoding a putative LOV photoreceptor, in addition to two genes encoding BLUF proteins. This suggests that blue light sensing could play a role in X. axonopodis pv. citri physiology. We obtained the recombinant Xac-LOV protein by expression in Escherichia coli and performed a spectroscopic analysis of the purified protein, which demonstrated that it has a canonical LOV photochemistry. We also constructed a mutant strain of X. axonopodis pv. citri lacking the LOV protein and found that the loss of this protein altered bacterial motility, exopolysaccharide production and biofilm formation. Moreover, we observed that the adhesion of the mutant strain to abiotic and biotic surfaces was significantly diminished compared to the wild-type. Finally, inoculation of orange (Citrus sinensis leaves with the mutant strain of X. axonopodis pv. citri resulted in marked differences in the development of symptoms in plant tissues relative to the wild-type, suggesting a role for the Xac-LOV protein in the pathogenic process. Altogether, these results suggest the novel involvement of a photosensory system in the regulation of physiological attributes of a phytopathogenic bacterium. A functional blue light receptor in Xanthomonas spp. has been described for the first time, showing

  4. Plant Phosphoproteomics: Analysis of Plasma Membrane Transporters by Mass Spectrometry

    DEFF Research Database (Denmark)

    Ye, Juanying; Rudashevskaya, Elena; Young, Clifford

    important physiological functions, such as stomata aperture, cell elongation, or cellular pH regulation. It is known that the activity of plant plasma membrane H+-ATPase is regulated by phosphorylation. Therefore, we first investigated the phosphorylation profile of plant H+-ATPase by enriching...... the phosphopeptides with optimized TiO2 and IMAC enrichment methods prior to MS analysis. We further investigated the global phosphorylation profile of the whole plant plasma membrane proteins using the combination of our recently established phosphopeptide enrichment method, Calcium phosphate precipitation......  Phosphorylation is a key regulatory factor in all aspects of eukaryotic biology including the regulation of plant membrane-bound transport proteins. To date, mass spectrometry (MS) has been introduced as powerful technology for study of post translational modifications (PTMs), including protein...

  5. Gravity Plant Physiology Facility (GPPF) Team in the Spacelab Payload Operations Control Center (SL

    Science.gov (United States)

    1992-01-01

    The primary payload for Space Shuttle Mission STS-42, launched January 22, 1992, was the International Microgravity Laboratory-1 (IML-1), a pressurized manned Spacelab module. The goal of IML-1 was to explore in depth the complex effects of weightlessness of living organisms and materials processing. Around-the-clock research was performed on the human nervous system's adaptation to low gravity and effects of microgravity on other life forms such as shrimp eggs, lentil seedlings, fruit fly eggs, and bacteria. Materials processing experiments were also conducted, including crystal growth from a variety of substances such as enzymes, mercury iodide, and a virus. The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Featured is the Gravity Plant Physiology Facility (GPPF) team in the SL POCC during the IML-1 mission.

  6. Gravity Plant Physiology Facility (GPPF) Team in the Spacelab Payload Operations Control Center (SL

    Science.gov (United States)

    1992-01-01

    The primary payload for Space Shuttle Mission STS-42, launched January 22, 1992, was the International Microgravity Laboratory-1 (IML-1), a pressurized manned Spacelab module. The goal of IML-1 was to explore in depth the complex effects of weightlessness of living organisms and materials processing. Around-the-clock research was performed on the human nervous system's adaptation to low gravity and effects of microgravity on other life forms such as shrimp eggs, lentil seedlings, fruit fly eggs, and bacteria. Materials processing experiments were also conducted, including crystal growth from a variety of substances such as enzymes, mercury iodide, and a virus. The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Featured is the Gravity Plant Physiology Facility (GPPF) team in the SL POCC during the IML-1 mission.

  7. Instrumentation enabling study of plant physiological response to elevated night temperature

    Directory of Open Access Journals (Sweden)

    Tarpley Lee

    2009-06-01

    Full Text Available Abstract Background Global climate warming can affect functioning of crops and plants in the natural environment. In order to study the effects of global warming, a method for applying a controlled heating treatment to plant canopies in the open field or in the greenhouse is needed that can accept either square wave application of elevated temperature or a complex prescribed diurnal or seasonal temperature regime. The current options are limited in their accuracy, precision, reliability, mobility or cost and scalability. Results The described system uses overhead infrared heaters that are relatively inexpensive and are accurate and precise in rapidly controlling the temperature. Remote computer-based data acquisition and control via the internet provides the ability to use complex temperature regimes and real-time monitoring. Due to its easy mobility, the heating system can randomly be allotted in the open field or in the greenhouse within the experimental setup. The apparatus has been successfully applied to study the response of rice to high night temperatures. Air temperatures were maintained within the set points ± 0.5°C. The incorporation of the combination of air-situated thermocouples, autotuned proportional integrative derivative temperature controllers and phase angled fired silicon controlled rectifier power controllers provides very fast proportional heating action (i.e. 9 ms time base, which avoids prolonged or intense heating of the plant material. Conclusion The described infrared heating system meets the utilitarian requirements of a heating system for plant physiology studies in that the elevated temperature can be accurately, precisely, and reliably controlled with minimal perturbation of other environmental factors.

  8. Phylogeny, physiology and distribution of 'Candidatus Microthrix calida', a new Microthrix species isolated from industrial activated sludge wastewater treatment plants.

    Science.gov (United States)

    Levantesi, Caterina; Rossetti, Simona; Thelen, Karin; Kragelund, Caroline; Krooneman, Janneke; Eikelboom, Dick; Nielsen, Per Halkjaer; Tandoi, Valter

    2006-09-01

    Twelve strains of filamentous bacteria morphologically identified as 'Microthrix parvicella' were isolated from industrial activated sludge wastewater treatment plants. 16S rRNA gene sequences analysis showed that these strains were all closely related to 'Candidatus Microthrix parvicella'. Six of them, however, had a 16S rRNA gene similarity of only 95.7% and 96.7% to 'Candidatus Microthrix parvicella' suggesting the presence of a new species. The name 'Candidatus Microthrix calida' is proposed for this new microorganism. The physiological properties of these six isolates supported the description of a new taxon. The 'Candidatus Microthrix calida' strains produced thin filaments (0.3-0.7 microm diameter), they did not grow on the media supporting the growth of 'Candidatus Microthrix parvicella' and could be cultivated at higher temperature (up to 36.5 degrees C). Preliminary data on substrate uptake were obtained by microautoradiography on pure culture. Two new fluorescence in situ hybridization (FISH) probes, Mpa-T1-1260 specific for 'Candidatus Microthrix calida' and Mpa-all-1410 targeting both Microthrix species, were designed. The presence of Microthrix spp. was investigated in 114 activated sludge plants. 'Microthrix parvicella' morphotype was detected in 23% of the analysed samples and FISH analysis revealed that 'Candidatus Microthrix calida' was present in 5% of them. The remaining 'M. parvicella' filaments were positive with probe Mpa-all-1410 but could not all be identified as 'Candidatus Microthrix parvicella' suggesting the presence of more hitherto undescribed biodiversity within this morphotype.

  9. Cotransport of water and solutes in plant membranes: The molecular basis, and physiological functions

    Directory of Open Access Journals (Sweden)

    Lars H. Wegner

    2017-03-01

    Full Text Available Current concepts of plant membrane transport are based on the assumption that water and solutes move across membranes via separate pathways. According to this view, coupling between the fluxes is more or less exclusively constituted via the osmotic force that solutes exert on water transport. This view is questioned here, and experimental evidence for a cotransport of water and solutes is reviewed. The overview starts with ion channels that provide pathways for both ion and water transport, as exemplified for maxi K+ channels from cytoplasmic droplets of Chara corallina. Aquaporins are usually considered to be selective for water (just allowing for slippage of some other small, neutral molecules. Recently, however, a “dual function” aquaporin has been characterized from Arabidopsis thaliana (AtPIP2.1 that translocates water and at the same time conducts cations, preferentially Na+. By analogy with mammalian physiology, other candidates for solute-water flux coupling are cation-chloride cotransporters of the CCC type, and transporters of sugars and amino acids. The last part is dedicated to possible physiological functions that could rely on solute-water cotransport. Among these are the generation of root pressure, refilling of embolized xylem vessels, fast turgor-driven movements of leaves, cell elongation (growth, osmoregulation and adjustment of buoyancy in marine algae. This review will hopefully initiate further research in the field.

  10. A molecular physiological review of vegetative desiccation tolerance in the resurrection plant Xerophyta viscosa (Baker).

    Science.gov (United States)

    Farrant, Jill M; Cooper, Keren; Hilgart, Amelia; Abdalla, Kamal O; Bentley, Joanne; Thomson, Jennifer A; Dace, Halford J W; Peton, Nashied; Mundree, Sagadevan G; Rafudeen, Mohamed S

    2015-08-01

    Provides a first comprehensive review of integrated physiological and molecular aspects of desiccation tolerance Xerophyta viscosa. A synopsis of biotechnological studies being undertaken to improve drought tolerance in maize is given. Xerophyta viscosa (Baker) is a monocotyledonous resurrection plant from the family Vellociacea that occurs in summer-rainfall areas of South Africa, Lesotho and Swaziland. It inhabits rocky terrain in exposed grasslands and frequently experiences periods of water deficit. Being a resurrection plant it tolerates the loss of 95% of total cellular water, regaining full metabolic competency within 3 days of rehydration. In this paper, we review some of the molecular and physiological adaptations that occur during various stages of dehydration of X. viscosa, these being functionally grouped into early and late responses, which might be relevant to the attainment of desiccation tolerance. During early drying (to 55% RWC) photosynthesis is shut down, there is increased presence and activity of housekeeping antioxidants and a redirection of metabolism to the increased formation of sucrose and raffinose family oligosaccharides. Other metabolic shifts suggest water replacement in vacuoles proposed to facilitate mechanical stabilization. Some regulatory processes observed include increased presence of a linker histone H1 variant, a Type 2C protein phosphatase, a calmodulin- and an ERD15-like protein. During the late stages of drying (to 10% RWC) there was increased expression of several proteins involved in signal transduction, and retroelements speculated to be instrumental in gene silencing. There was induction of antioxidants not typically found in desiccation-sensitive systems, classical stress-associated proteins (HSP and LEAs), proteins involved in structural stabilization and those associated with changes in various metabolite pools during drying. Metabolites accumulated in this stage are proposed, inter alia, to facilitate subcellular

  11. Plant phenomics and the need for physiological phenotyping across scales to narrow the genotype-to-phenotype knowledge gap

    DEFF Research Database (Denmark)

    Grosskinsky, Dominik Kilian; Svensgaard, Jesper; Christensen, Svend

    2015-01-01

    Plants are affected by complex genome×environment×management interactions which determine phenotypic plasticity as a result of the variability of genetic components. Whereas great advances have been made in the cost-efficient and high-throughput analyses of genetic information and non-invasive......-throughput non-invasive phenotyping needs to be validated and verified across scales to be used as proxy for the underlying processes. Armed with this interdisciplinary and multidimensional phenomics approach, plant physiology, non-invasive phenotyping, and functional genomics will complement each other...... of the internal phenotype into high-throughput phenotyping of whole plants and canopies. By this means, complex traits can be broken down into individual components of physiological traits. Since the higher resolution of physiological phenotyping by ‘wet chemistry’ is inherently limited in throughput, high...

  12. Plant phenomics and the need for physiological phenotyping across scales to narrow the genotype-to-phenotype knowledge gap.

    Science.gov (United States)

    Großkinsky, Dominik K; Svensgaard, Jesper; Christensen, Svend; Roitsch, Thomas

    2015-09-01

    Plants are affected by complex genome×environment×management interactions which determine phenotypic plasticity as a result of the variability of genetic components. Whereas great advances have been made in the cost-efficient and high-throughput analyses of genetic information and non-invasive phenotyping, the large-scale analyses of the underlying physiological mechanisms lag behind. The external phenotype is determined by the sum of the complex interactions of metabolic pathways and intracellular regulatory networks that is reflected in an internal, physiological, and biochemical phenotype. These various scales of dynamic physiological responses need to be considered, and genotyping and external phenotyping should be linked to the physiology at the cellular and tissue level. A high-dimensional physiological phenotyping across scales is needed that integrates the precise characterization of the internal phenotype into high-throughput phenotyping of whole plants and canopies. By this means, complex traits can be broken down into individual components of physiological traits. Since the higher resolution of physiological phenotyping by 'wet chemistry' is inherently limited in throughput, high-throughput non-invasive phenotyping needs to be validated and verified across scales to be used as proxy for the underlying processes. Armed with this interdisciplinary and multidimensional phenomics approach, plant physiology, non-invasive phenotyping, and functional genomics will complement each other, ultimately enabling the in silico assessment of responses under defined environments with advanced crop models. This will allow generation of robust physiological predictors also for complex traits to bridge the knowledge gap between genotype and phenotype for applications in breeding, precision farming, and basic research. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please

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

    Directory of Open Access Journals (Sweden)

    O. M. Vasilyuk

    2015-10-01

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

  14. Plastoquinone and Ubiquinone in Plants: Biosynthesis, Physiological Function and Metabolic Engineering

    Science.gov (United States)

    Liu, Miaomiao; Lu, Shanfa

    2016-01-01

    review, we summarize and discuss recent research progresses in the biosynthetic pathways of PQ and UQ and enzymes and their encoding genes involved in side chain elongation and in the second stage of PQ and UQ biosynthesis. Physiological functions of PQ and UQ played in plants as well as the practical application and metabolic engineering of PQ and UQ are also included. PMID:28018418

  15. Plastoquinone and ubiquinone in plants: biosynthesis, physiological function and metabolic engineering

    Directory of Open Access Journals (Sweden)

    Miaomiao Liu

    2016-12-01

    tested. In this review, we summarize and discuss recent research progresses in the biosynthetic pathways of PQ and UQ and enzymes and their encoding genes involved in side chain elongation and in the second stage of PQ and UQ biosynthesis. Physiological functions of PQ and UQ played in plants as well as the practical application and metabolic engineering of PQ and UQ are also included.

  16. [Molecular, genetic and physiological analysis of photoinhibition and photosynthetic

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    A major goal of this project is to use a combined molecular genetic, biochemical and physiological approach to understand the relationship between photosynthetic performance and the structure of the multifunctional D1 reaction center protein of Photosystem II encoded by the chloroplast psbA gene. Relative to other chloroplast proteins, turover of D1 is rapid and highly light dependent and de novo synthesis of D1 is required for a plant's recovery from short term exposure to irradiances which induce photoinhibitory damage. These observations have led to models for a damage/repair cycle of PSII involving the targeted degradation and replacement of photodamaged D1. To investigate the effects of perturbing the D1 cycle on photosynthesis and autotrophic growth under high and low irradiance, we have examined the consequences of site-specific mutations of the psbA and 16S rRNA genes affecting synthesis, maturation and function/stability of the D1 protein introduced into the chloroplast genome of wildtype strain of the green alga Chlamydomonas reinhardtii using biolistic transformation.

  17. POEAS: Automated Plant Phenomic Analysis Using Plant Ontology.

    Science.gov (United States)

    Shameer, Khader; Naika, Mahantesha Bn; Mathew, Oommen K; Sowdhamini, Ramanathan

    2014-01-01

    Biological enrichment analysis using gene ontology (GO) provides a global overview of the functional role of genes or proteins identified from large-scale genomic or proteomic experiments. Phenomic enrichment analysis of gene lists can provide an important layer of information as well as cellular components, molecular functions, and biological processes associated with gene lists. Plant phenomic enrichment analysis will be useful for performing new experiments to better understand plant systems and for the interpretation of gene or proteins identified from high-throughput experiments. Plant ontology (PO) is a compendium of terms to define the diverse phenotypic characteristics of plant species, including plant anatomy, morphology, and development stages. Adoption of this highly useful ontology is limited, when compared to GO, because of the lack of user-friendly tools that enable the use of PO for statistical enrichment analysis. To address this challenge, we introduce Plant Ontology Enrichment Analysis Server (POEAS) in the public domain. POEAS uses a simple list of genes as input data and performs enrichment analysis using Ontologizer 2.0 to provide results in two levels, enrichment results and visualization utilities, to generate ontological graphs that are of publication quality. POEAS also offers interactive options to identify user-defined background population sets, various multiple-testing correction methods, different enrichment calculation methods, and resampling tests to improve statistical significance. The availability of such a tool to perform phenomic enrichment analyses using plant genes as a complementary resource will permit the adoption of PO-based phenomic analysis as part of analytical workflows. POEAS can be accessed using the URL http://caps.ncbs.res.in/poeas.

  18. Physiological Responses and Yield of Wheat Plants in Zinc-Mediated Alleviation of Drought Stress

    Directory of Open Access Journals (Sweden)

    Dongyun Ma

    2017-05-01

    Full Text Available To evaluate the physiological responses of wheat to zinc (Zn fertilizer application under drought stress, pot, and field experiments were conducted on wheat plants grown under different soil moistures and treated with soil and foliar Zn applications. Photosynthetic characteristics, antioxidant content, Zn element concentration, and the transcription level of genes involved in antioxidant biosynthesis were analyzed. Zn application increased SPAD and Fv/Fm of wheat flag leaves, while decreased lipid peroxidation levels and H2O2 content. Zn application increased the antioxidant content (ascorbate, reduced glutathione, total phenolic, and total flavonoid of wheat flag leaves, and enhanced the relative expression levels of two antioxidant enzyme genes, four ascorbate–glutathione cycle genes, and two flavonoid biosynthesis pathway genes under drought stress. Soil Zn application increased grain yield and Zn concentration by 10.5 and 15.8%, 22.6 and 9.7%, and 28.2 and 32.8% under adequate water supply, moderate drought, and severe drought, respectively. Furthermore, foliar application of Zn in the field increased grain yield and grain Zn concentration under both adequate water supply and rain-fed conditions. Zn plays a role in alleviating wheat plant drought stress by Zn-mediated increase in photosynthesis pigment and active oxygen scavenging substances, and reduction in lipid peroxidation. Furthermore, Zn fertilizer could regulate multiple antioxidant defense systems at the transcriptional level in response to drought.

  19. EDTA reduces the physiological damage of lead on cardoon plants grown hydroponically

    Science.gov (United States)

    Hernandez-Allica, J.; Barrutia, O.; Becerril, J. M.; Garbisu, C.

    2003-05-01

    Cardoon seedlings (Cynara cardunculus L.) were grown hydroponically in nutrient solution and exposed to lead (Pb^{2+}: ImM) in the presence of a range of different EDTA concentrations (EDTANa2: 0, 0.5, 1 or 2mM). Analyses were performed to establish whether the coordination of Pb^{2+} transport by EDTA enhances the mobility of this metal within the plant and to determine the toxic effects of these treatments during a phytoextraction process. Net photosynthesis, transpiration rate and stomatal conductance decreased dramatically in plants treated with Pb^{2+} or Pb-EDTA at doses below 1 mM. ln these treatments, most of the Pb^{2+} accumulated in the roots, alld only a very low amount of it was translocated to the shoots. Increasing the EDTA doses up to Pb^{2+} equimolarity, increased the Pb^{2+} shoot content more than 10-fold without any physiological evidence of toxicity. The treatment with higher doses of EDTA (Pb^{2+} 1 mM + EDTA 2 mM) did not show toxicity symptoms, but the Pb^{2+} concentration in the aboveground tissues decreased when compared with the equimolar treatment. The interaction with the absorption of some essential cations such as Ca^{2+} and phytotoxicity on chelated-assisted phytoextraction is discussed.

  20. Plant physiological ecology and the global changes Ecofisiologia vegetal e as mudanças globais

    Directory of Open Access Journals (Sweden)

    João Paulo Rodrigues Alves Delfino Barbosa

    2012-06-01

    Full Text Available The global changes are marked by alteration on the normal patterns of important biochemical and biophysical processes of the Earth. However, the real effects as well as the feedbacks of the global changes over vegetation are still unclear. Part of this uncertainty can be attributed to the inattention of stakeholders and scientists towards vegetation and its complex interrelations with the environment, which drive plant physiological processes in different space-time scales. Notwithstanding, some key subjects of the global changes could be better elucidated with a more plant physiological ecology approach. We discuss some issues related to this topic, going through some limitations of approaching vegetation as a static component of the biosphere as the other sub-systems of the Earth-system change. With this perspective, this review is an initial reflection towards the assessment of the role and place of vegetation structure and function in the global changes context. We reviewed the Earth-system and global changes terminology; attempted to illustrate key plant physiological ecology researches themes in the global changes context; consider approaching plants as complex systems in order to adequately quantify systems characteristics as sensibility, homeostasis, and vulnerability. Moreover, we propose insights that would allow vegetation studies and scaling procedures in the context of the Earth-system. We hope this review will assist researchers on their strategy to identify, understand and anticipate the potential effects of global changes over the most vulnerable vegetation processes from the leaf to the global levels.As mudanças globais englobam importantes alterações nos padrões normais de processos bioquímicos e biofísicos da Terra. Os reais efeitos e retroalimentações das mudanças globais sobre a vegetação ainda são incertos. Parte das incertezas pode ser atribuída à falta de atenção de cientistas e políticos para a vegeta

  1. Extreme climatic events: impacts of drought and high temperature on physiological processes in agronomically important plants

    Directory of Open Access Journals (Sweden)

    Urs eFeller

    2014-10-01

    Full Text Available Climate models predict more frequent and more severe extreme events (e.g. heat waves, extended drought periods, flooding in many regions for the next decades. The impact of adverse environmental conditions on crop plants is ecologically and economically relevant. This review is focused on drought and heat effects on physiological status and productivity of agronomically important plants. Stomatal opening represents an important regulatory mechanism during drought and heat stress since it influences simultaneously water loss via transpiration and CO2 diffusion into the leaf apoplast which further is utilized in photosynthesis. Along with the reversible short-term control of stomatal opening, stomata and leaf epidermis may produce waxy deposits and irreversibly down-regulate the stomatal conductance and non-stomatal transpiration. As a consequence photosynthesis will be negatively affected. Rubisco activase - a key enzyme in keeping the Calvin cycle functional – is heat-sensitive and may become a limiting factor at elevated temperature. The accumulated reactive oxygen species during stress represent an additional challenge under unfavorable conditions. Drought and heat cause accumulation of free amino acids which are partially converted into compatible solutes such as proline. This is accompanied by lower rates of both nitrate reduction and de novo amino acid biosynthesis. Protective proteins (e.g. dehydrins, chaperones, antioxidant enzymes or the key enzyme for proline biosynthesis play an important role in leaves and may be present at higher levels under water deprivation or high temperatures. On the whole plant level, effects on long-distance translocation of solutes via xylem and phloem and on leaf senescence (e.g. anticipated, accelerated or delayed senescence are important. The factors mentioned above are relevant for the overall performance of crops under drought and heat and must be considered for genotype selection and breeding programs.

  2. A new cadmium reduction device for the microplate determination of nitrate in water, soil, plant tissue, and physiological fluids.

    Science.gov (United States)

    Crutchfield, James D; Grove, John H

    2011-01-01

    A reusable catalytic reductor consisting of 96 copperized-cadmium pins attached to a microplate lid was developed to simultaneously reduce nitrate (NO3-) to nitrite (NO2-) in all wells of a standard microplate. The resulting NO2- is analyzed colorimetrically by the Griess reaction using a microplate reader. Nitrate data from groundwater samples analyzed using the new device correlated well with data obtained by ion chromatography (r2 = 0.9959). Soil and plant tissue samples previously analyzed for NO3- in an interlaboratory validation study sponsored by the Soil Science Society of America were also analyzed using the new technique. For the soil sample set, the data are shown to correlate well with the other methods used (r2 = 0.9976). Plant data correlated less well, especially for samples containing low concentrations of NO3-. Reasons for these discrepancies are discussed, and new techniques to increase the accuracy of the analysis are explored. In addition, a method is presented for analyzing NO3- in physiological fluids (blood serum and urine) after matrix modification with Somogyi's reagent. A protocol for statistical validation of data when analyzing samples with complex matrixes is also established. The simplicity, adaptability, and low cost of the device indicate its potential for widespread application.

  3. Physiological effects of climate warming on flowering plants and insect pollinators and potential consequences for their interactions

    Institute of Scientific and Technical Information of China (English)

    Victoria L.SCAVEN; Nicole E.RAFFERTY

    2013-01-01

    Growing concern about the influence of climate change on flowering plants,pollinators,and the mutualistic interactions between them has led to a recent surge in research.Much of this research has addressed the consequences of warming for phenological and distributional shifts.In contrast,relatively little is known about the physiological responses of plants and insect pollinators to climate warming and,in particular,how these responses might affect plant-pollinator interactions.Here,we summabrize the direct physiological effects of temperature on flowering plants and pollinating insects to highlight ways in which plant and pollinator responses could affect floral resources for pollinators,and pollination success for plants,respectively.We also consider the overall effects of these responses on plant-pollinator interaction networks.Plant responses to warming,which include altered flower,nectar,and pollen production,could modify floral resource availability and reproductive output of pollinating insects.Similarly,pollinator responses,such as altered foraging activity,body size,and life span,could affect patterns of pollen flow and pollination success of flowering plants.As a result,network structure could be altered as interactions are gained and lost,weakened and strengthened,even without the gain or loss of species or temporal overlap.Future research that addresses not only how plant and pollinator physiology are affected by warming but also how responses scale up to affect interactions and networks should allow us to better understand and predict the effects of climate change on this important ecosystem service.

  4. Differences in Copper Absorption and Accumulation between Copper-Exclusion and Copper-Enrichment Plants: A Comparison of Structure and Physiological Responses.

    Science.gov (United States)

    Fu, Lei; Chen, Chen; Wang, Bin; Zhou, Xishi; Li, Shuhuan; Guo, Pan; Shen, Zhenguo; Wang, Guiping; Chen, Yahua

    2015-01-01

    Differences in copper (Cu) absorption and transport, physiological responses and structural characteristics between two types of Cu-resistant plants, Oenothera glazioviana (Cu-exclusion type) and Elsholtzia haichowensis (Cu-enrichment type), were investigated in the present study. The results indicated the following: (1) After 50 μM Cu treatment, the Cu ratio in the xylem vessels of E. haichowensis increased by 60%. A Cu adsorption experiment indicated that O. glazioviana exhibited greater resistance to Cu, and Cu absorption and the shoot/root ratio of Cu were significantly lower in O. glazioviana than in E. haichowensis. (2) An analysis of the endogenous abscisic acid (ABA) variance and exogenous ABA treatment demonstrated that the ABA levels of both plants did not differ; exogenous ABA treatment clearly reduced Cu accumulation in both plants. (3) The leaf stomatal density of O. glazioviana was significantly less than that of E. haichowensis. Guard cells in E. haichowensis plants were covered with a thick cuticle layer, the epidermal hair was more numerous and longer, and the number of xylem conduits in the root was small. (4) The transpiration rate and the stomatal conductance of O. glazioviana were both significantly lower than those of E. haichowensis, regardless of whether the plants were treated with Cu. Taken together, these results indicate that the differences in the structural characteristics between these two plant species, particularly in the characteristics related to plant transpiration, are important factors that govern whether plants acquire or exclude Cu.

  5. Differences in Copper Absorption and Accumulation between Copper-Exclusion and Copper-Enrichment Plants: A Comparison of Structure and Physiological Responses.

    Directory of Open Access Journals (Sweden)

    Lei Fu

    Full Text Available Differences in copper (Cu absorption and transport, physiological responses and structural characteristics between two types of Cu-resistant plants, Oenothera glazioviana (Cu-exclusion type and Elsholtzia haichowensis (Cu-enrichment type, were investigated in the present study. The results indicated the following: (1 After 50 μM Cu treatment, the Cu ratio in the xylem vessels of E. haichowensis increased by 60%. A Cu adsorption experiment indicated that O. glazioviana exhibited greater resistance to Cu, and Cu absorption and the shoot/root ratio of Cu were significantly lower in O. glazioviana than in E. haichowensis. (2 An analysis of the endogenous abscisic acid (ABA variance and exogenous ABA treatment demonstrated that the ABA levels of both plants did not differ; exogenous ABA treatment clearly reduced Cu accumulation in both plants. (3 The leaf stomatal density of O. glazioviana was significantly less than that of E. haichowensis. Guard cells in E. haichowensis plants were covered with a thick cuticle layer, the epidermal hair was more numerous and longer, and the number of xylem conduits in the root was small. (4 The transpiration rate and the stomatal conductance of O. glazioviana were both significantly lower than those of E. haichowensis, regardless of whether the plants were treated with Cu. Taken together, these results indicate that the differences in the structural characteristics between these two plant species, particularly in the characteristics related to plant transpiration, are important factors that govern whether plants acquire or exclude Cu.

  6. Plant physiological models of heat, water and photoinhibition stress for climate change modelling and agricultural prediction

    Science.gov (United States)

    Nicolas, B.; Gilbert, M. E.; Paw U, K. T.

    2015-12-01

    Soil-Vegetation-Atmosphere Transfer (SVAT) models are based upon well understood steady state photosynthetic physiology - the Farquhar-von Caemmerer-Berry model (FvCB). However, representations of physiological stress and damage have not been successfully integrated into SVAT models. Generally, it has been assumed that plants will strive to conserve water at higher temperatures by reducing stomatal conductance or adjusting osmotic balance, until potentially damaging temperatures and the need for evaporative cooling become more important than water conservation. A key point is that damage is the result of combined stresses: drought leads to stomatal closure, less evaporative cooling, high leaf temperature, less photosynthetic dissipation of absorbed energy, all coupled with high light (photosynthetic photon flux density; PPFD). This leads to excess absorbed energy by Photosystem II (PSII) and results in photoinhibition and damage, neither are included in SVAT models. Current representations of photoinhibition are treated as a function of PPFD, not as a function of constrained photosynthesis under heat or water. Thus, it seems unlikely that current models can predict responses of vegetation to climate variability and change. We propose a dynamic model of damage to Rubisco and RuBP-regeneration that accounts, mechanistically, for the interactions between high temperature, light, and constrained photosynthesis under drought. Further, these predictions are illustrated by key experiments allowing model validation. We also integrated this new framework within the Advanced Canopy-Atmosphere-Soil Algorithm (ACASA). Preliminary results show that our approach can be used to predict reasonable photosynthetic dynamics. For instances, a leaf undergoing one day of drought stress will quickly decrease its maximum quantum yield of PSII (Fv/Fm), but it won't recover to unstressed levels for several days. Consequently, cumulative effect of photoinhibition on photosynthesis can cause

  7. Automatic physiological waveform processing for FMRI noise correction and analysis.

    Directory of Open Access Journals (Sweden)

    Daniel J Kelley

    Full Text Available Functional MRI resting state and connectivity studies of brain focus on neural fluctuations at low frequencies which share power with physiological fluctuations originating from lung and heart. Due to the lack of automated software to process physiological signals collected at high magnetic fields, a gap exists in the processing pathway between the acquisition of physiological data and its use in fMRI software for both physiological noise correction and functional analyses of brain activation and connectivity. To fill this gap, we developed an open source, physiological signal processing program, called PhysioNoise, in the python language. We tested its automated processing algorithms and dynamic signal visualization on resting monkey cardiac and respiratory waveforms. PhysioNoise consistently identifies physiological fluctuations for fMRI noise correction and also generates covariates for subsequent analyses of brain activation and connectivity.

  8. Evaluation of structural and physiological plant characteristics in relation to the distribution of cadmium in maize inbred lines.

    NARCIS (Netherlands)

    Florijn, P.J.; Nelemans, J.A.; Beusichem, van M.L.

    1993-01-01

    To establish the structural and physiological characteristics related to the genotypic variation in Cd distribution between maize inbred lines (shoot Cd excluders and non-shoot Cd excluders), shoot and root morphological parameters were studied on plants grown in nutrient solution. Furthermore, the

  9. The Use of Light-Emitting Diodes (LEDs) as Green and Red/Far-Red Light Sources in Plant Physiology.

    Science.gov (United States)

    Jackson, David L.; And Others

    1985-01-01

    The use of green, red, and far-red light-emitting diodes (LEDs) as light sources for plant physiological studies is outlined and evaluated. Indicates that LED lamps have the advantage over conventional light sources in that they are lightweight, low-cost, portable, easily constructed, and do not require color filters. (Author/DH)

  10. Effect of Humic Acid and Organic Manure Tea on Plant Physiology and Fruit Characteristics of Pepino

    Directory of Open Access Journals (Sweden)

    Jamal Javanmardi

    2017-02-01

    Full Text Available Introduction Pepino (SolanummuricatumAit., a Solanaceous vegetable fruit has been recently introduced to Iran markets. Organic farming is currently the fastest growing agricultural sector worldwide. Although several investigations are available on chemical fertilization of pepino, the knowledge of organic fertilization ismostly lacking. Therefore, at the beginning of introducing pepino plant to Iranian farmers it worth to evaluate the impact of organic fertilization on the productivity, profitability, acceptability and sustainability of farming systemsto this plant. High chemical fertilization of pepinoincreases the vegetative growth over the generative and fruit production. The aim of this investigation was to introduce the possibility of organic production of pepino. Materials and Methods.A two-year experiment was carried out to assess the possibility of organic production of pepino using organic fertilizers. Humistar® organic fertilizer (containing 8.6% humic acid at 50 L/ha and sheep or cow manure teas at 1:10 and 1:5 ratios were used for production of pepino cv. Kanseola to evaluate their effects on the physiology of reproductive stage and some fruit quality characteristics. The experiments were arranged as factorial in a randomized complete block design comprised of 3 replications, each of which 10 plants. Mother plants were obtained from Mashhad Ferdowsi University and incubated in a greenhouse (mean temperature of 25 °C and 60-70% relative humidity for 1 month to proliferate. Cuttings with 2-3 leaves at the top, 3-5 healthy buds and 20 cm length were rooted for 14 days in a rooting media, ( 1:1:2 of field soil, composted leaf and perlite, respectively. Plants were transplanted into the field in 100 × 75 cm spacing after the danger of frost was over. Treatments consisted of two levels of 1:5 and 1:10 (w:w cow or sheep manure teas in combination with two levels of Humistar® organic fertilizer as 0 and 50L/ha levels. Control plants

  11. Incorporation of {sup 137}Cs by tropical tree species and its correlation with plant physiology

    Energy Technology Data Exchange (ETDEWEB)

    Cid, Alberto Silva; Anjos, Roberto Meigikos dos; Macario, K.D.; Veiga, R.; Ayubi, J. Juri; Lacerda, T. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Instituto de Fisica; Zamboni, C.B.; Medeiros, I.M.A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN- SP), Sao Paulo, SP (Brazil); Velasco, H.; Rizzotto, M. [Universidad Nacional de San Luis (UNSL) (Argentina). Instituto de Matematica Aplicada San Luis; Audicio, P. [Facultad de Ciencias (UDELAR), Montevideo (Uruguay). Centro de Investigaciones Nucleares

    2011-07-01

    Environmental phenomena associated with potential releases of radionuclides to terrestrial ecosystems have attracted the interest of several researches around the world. However, such interest has not been focused exclusively in its effects on human health. Several radionuclides have also been used as tracers of physicochemical or biological phenomena. These studies depend on both the development of auxiliary analysis techniques, which help to improve the results of traditional methods, and the production of additional data, so that a wide variety of natural processes can be understood. In this sense, the same radiometric results can be analyzed or interpreted from different viewpoints, allowing the interdisciplinary understanding of the overall structure of terrestrial ecosystems. {sup 137}Cs, for example, is one of the main fission products of nuclear reactors and atmospheric nuclear testing that is persistent in the biosphere because of its half-life of 30.2 years and biological mobility. This radionuclide remains in the top soil due to fixation and adsorption to clay minerals and organic matter, persisting in the root zone of plant for a long period of time. As its chemical behavior is similar to other monovalent inorganic cations (such as NH{sup +}{sub 4} , Na{sup +} and K{sup +}), Cs{sup +} can be readily absorbed by roots and translocated to the aboveground parts of plant. In this work, concentrations of {sup 137}Cs{sup +}, K{sup +} and Na{sup +} in fruits of lemon (Citrus limon B.) and coconut (Cocos nucifera L.) were measured by both gamma spectrometry and neutron activation analysis, with the aim to understand the behavior of monovalent inorganic cations in tropical plants as well as the plant ability to store these elements. In contrast to K{sup +} and Na{sup +}, Cs{sup +} is not an essential element to plants. However, our results have shown that {sup 137}Cs{sup +} incorporation to vegetal tissues is positively correlated to K{sup +} distribution inside

  12. Biochemical and physiological changes in plants as a result of different sonic exposures.

    Science.gov (United States)

    Qin, Yu-Chuan; Lee, Won-Chu; Choi, Young-Cheol; Kim, Tae-Wan

    2003-07-01

    The effects of two different sonic exposures on two vegetables, namely Chinese cabbage and cucumber at two growth stages, including seedlings and mature plants were investigated. The 3 h exposures included either 20 kHz sound waves or "green music" that comprised classic music and natural sounds such as those of birds, insects, water, etc. Analysis of variance between groups (ANOVA) was used to determine the appropriate statistics parameters for the different treatments. Both exposures caused significant elevations in the level of polyamines (PAs) and increased uptake of oxygen O(2) in comparison with the controls. For Chinese cabbage the highest PAs' levels were determined for both seedlings and mature plants that were exposed to "green music". The oxygen uptake in Chinese cabbage also increased as a result of sonic exposures, and the highest oxygen uptake was also observed after "green music" treatment. For cucumber, the highest content of PAs for both seedlings and mature cucumber plants was determined as a result of 20 kHz ultrasound exposure. 20 kHz exposure of mature plants also resulted in the highest level of oxygen uptake. No statistically significant differences in the vitamin C level were determined between the different sonic treatments and sham exposed vegetables.

  13. Physiological and transcriptomic aspects of urea uptake and assimilation in Arabidopsis plants.

    Science.gov (United States)

    Mérigout, Patricia; Lelandais, Maud; Bitton, Frédérique; Renou, Jean-Pierre; Briand, Xavier; Meyer, Christian; Daniel-Vedele, Françoise

    2008-07-01

    Urea is the major nitrogen (N) form supplied as fertilizer in agriculture, but it is also an important N metabolite in plants. Urea transport and assimilation were investigated in Arabidopsis (Arabidopsis thaliana). Uptake studies using (15)N-labeled urea demonstrated the capacity of Arabidopsis to absorb urea and that the urea uptake was regulated by the initial N status of the plants. Urea uptake was stimulated by urea but was reduced by the presence of ammonium nitrate in the growth medium. N deficiency in plants did not affect urea uptake. Urea exerted a repressive effect on nitrate influx, whereas urea enhanced ammonium uptake. The use of [(15)N]urea and [(15)N]ammonium tracers allowed us to show that urea and ammonium assimilation pathways were similar. Finally, urea uptake was less efficient than nitrate uptake, and urea grown-plants presented signs of N starvation. We also report the first analysis, to our knowledge, of Arabidopsis gene expression profiling in response to urea. Our transcriptomic approach revealed that nitrate and ammonium transporters were transcriptionally regulated by urea as well as key enzymes of the glutamine synthetase-glutamate synthase pathway. AtDUR3, a high-affinity urea transporter in Arabidopsis, was strongly up-regulated by urea. Moreover, our transcriptomic data suggest that other genes are also involved in urea influx.

  14. The signature of seeds in resurrection plants: a molecular and physiological comparison of desiccation tolerance in seeds and vegetative tissues.

    Science.gov (United States)

    Illing, Nicola; Denby, Katherine J; Collett, Helen; Shen, Arthur; Farrant, Jill M

    2005-11-01

    Desiccation-tolerance in vegetative tissues of angiosperms has a polyphyletic origin and could be due to 1) appropriation of the seed-specific program of gene expression that protects orthodox seeds against desiccation, and/or 2) a sustainable version of the abiotic stress response. We tested these hypotheses by comparing molecular and physiological data from the development of orthodox seeds, the response of desiccation-sensitive plants to abiotic stress, and the response of desiccation-tolerant plants to extreme water loss. Analysis of publicly-available gene expression data of 35 LEA proteins and 68 anti-oxidant enzymes in the desiccation-sensitive Arabidopsis thaliana identified 13 LEAs and 4 anti-oxidants exclusively expressed in seeds. Two (a LEA6 and 1-cys-peroxiredoxin) are not expressed in vegetative tissues in A. thaliana, but have orthologues that are specifically activated in desiccating leaves of Xerophyta humilis. A comparison of antioxidant enzyme activity in two desiccation-sensitive species of Eragrostis with the desiccation-tolerant E. nindensis showed equivalent responses upon initial dehydration, but activity was retained at low water content in E. nindensis only. We propose that these antioxidants are housekeeping enzymes and that they are protected from damage in the desiccation-tolerant species. Sucrose is considered an important protectant against desiccation in orthodox seeds, and we show that sucrose accumulates in drying leaves of E. nindensis, but not in the desiccation-sensitive Eragrostis species. The activation of "seed-specific" desiccation protection mechanisms (sucrose accumulation and expression of LEA6 and 1-cys-peroxiredoxin genes) in the vegetative tissues of desiccation-tolerant plants points towards acquisition of desiccation tolerance from seeds.

  15. Reversible, partial inactivation of plant betaine aldehyde dehydrogenase by betaine aldehyde: mechanism and possible physiological implications.

    Science.gov (United States)

    Zárate-Romero, Andrés; Murillo-Melo, Darío S; Mújica-Jiménez, Carlos; Montiel, Carmina; Muñoz-Clares, Rosario A

    2016-04-01

    In plants, the last step in the biosynthesis of the osmoprotectant glycine betaine (GB) is the NAD(+)-dependent oxidation of betaine aldehyde (BAL) catalysed by some aldehyde dehydrogenase (ALDH) 10 enzymes that exhibit betaine aldehyde dehydrogenase (BADH) activity. Given the irreversibility of the reaction, the short-term regulation of these enzymes is of great physiological relevance to avoid adverse decreases in the NAD(+):NADH ratio. In the present study, we report that the Spinacia oleracea BADH (SoBADH) is reversibly and partially inactivated by BAL in the absence of NAD(+)in a time- and concentration-dependent mode. Crystallographic evidence indicates that the non-essential Cys(450)(SoBADH numbering) forms a thiohemiacetal with BAL, totally blocking the productive binding of the aldehyde. It is of interest that, in contrast to Cys(450), the catalytic cysteine (Cys(291)) did not react with BAL in the absence of NAD(+) The trimethylammonium group of BAL binds in the same position in the inactivating or productive modes. Accordingly, BAL does not inactivate the C(450)SSoBADH mutant and the degree of inactivation of the A(441)I and A(441)C mutants corresponds to their very different abilities to bind the trimethylammonium group. Cys(450)and the neighbouring residues that participate in stabilizing the thiohemiacetal are strictly conserved in plant ALDH10 enzymes with proven or predicted BADH activity, suggesting that inactivation by BAL is their common feature. Under osmotic stress conditions, this novel partial and reversible covalent regulatory mechanism may contribute to preventing NAD(+)exhaustion, while still permitting the synthesis of high amounts of GB and avoiding the accumulation of the toxic BAL.

  16. An update: improvements in imaging perfluorocarbon-mounted plant leaves with implications for studies of plant pathology, physiology, development and cell biology.

    Directory of Open Access Journals (Sweden)

    George R Littlejohn

    2014-04-01

    Full Text Available Plant leaves are optically complex, which makes them difficult to image by light microscopy. Careful sample preparation is therefore required to enable researchers to maximise the information gained from advances in fluorescent protein labelling, cell dyes and innovations in microscope technologies and techniques. We have previously shown that mounting leaves in the non-toxic, non-fluorescent perfluorocarbon (PFC, perfluorodecalin (PFD enhances the optical properties of the leaf with minimal impact on physiology. Here, we assess the use of the perfluorocarbons PFD, and perfluoroperhydrophenanthrene (PP11 for in vivo plant leaf imaging using 4 advanced modes of microscopy: laser scanning confocal microscopy (LSCM, Two-photon fluorescence (TPF microscopy, second harmonic generation (SHG microscopy and stimulated Raman scattering (SRS microscopy. For every mode of imaging tested, we observed an improved signal when leaves were mounted in PFD or in PP11, compared to mounting the samples in water. Using an image analysis technique based on autocorrelation to quantitatively assess LSCM image deterioration with depth, we show that PP11 outperformed PFD as a mounting medium by enabling the acquisition of clearer images deeper into the tissue. In addition, we show that SRS microscopy can be used to image perfluorocarbons directly in the mesophyll and thereby easily delimit the negative space within a leaf, which may have important implications for studies of leaf development. Direct comparison of on and off resonance SRS micrographs show that PFCs do not to form intracellular aggregates in live plants. We conclude that the application of PFCs as mounting media substantially increases advanced microscopy image quality of living mesophyll and leaf vascular bundle cells.

  17. EFFECT OF DROUGHT STRESS INDUCED BY MANNITOL ON PHYSIOLOGICAL PARAMETERS OF MAIZE (ZEA MAYS L. SEEDLINGS AND PLANTS

    Directory of Open Access Journals (Sweden)

    Katarzyna Możdżeń

    2015-02-01

    Full Text Available Plants are exposed to various stress factors which might lead to structural damage and physiological function abnormalities. Drought is one of the environmental stress factors that reduce the productivity of plants. The aim of our study was to determine the influence of drought stress induced by mannitol (-0.5 and -1.5MPa on selected physiological processes in Z. mays L. In the first stage we studied the effect of mannitol on the germination. In the second stage the effect of mannitol on the growth of plants germinated on distilled water and watered with mannitol in growth phase were measured. Mannitol, which decreased the water content in a concentration-dependent manner, had an inhibitory effect on germination and growth of seedlings and adult plants. Electrolyte leakage of cell membranes of the Z. mays seedlings showed high disturbances in the functioning of the membrane structures in the osmotic drought conditions. Similar results were obtained for maize roots, shoots and leaves in both treatment studies. Chlorophyll content showed only significant differences in plants from treated during the growth phase. Drought stress caused a decrease in chlorophyll content by almost a half compared to the control plants. Measurements of chlorophyll fluorescence of plant leaves from the second stage of experiments showed changes in fluorescence activity parameters Fv/Fm, NPQ, Rfd, qP, ect.; gas exchange measurements also showed changes in activity in each of the two phases.

  18. Phenolic metabolites in carnivorous plants: Inter-specific comparison and physiological studies.

    Science.gov (United States)

    Kováčik, Jozef; Klejdus, Bořivoj; Repčáková, Klára

    2012-03-01

    Despite intensive phytochemical research, data related to the accumulation of phenols in carnivorous plants include mainly qualitative reports. We have quantified phenolic metabolites in three species: Drosera capensis, Dionaea muscipula and Nepenthes anamensis in the "leaf" (assimilatory part) and the "trap" (digestive part). For comparison, commercial green tea was analysed. Phenylalanine ammonia-lyase (PAL) activities in Dionaea and Nepenthes were higher in the trap than in the leaf while the opposite was found in Drosera. Soluble phenols and majority of phenolic acids were mainly accumulated in the trap among species. Flavonoids were abundant in Drosera and Dionaea traps but not in Nepenthes. Phenolic acids were preferentially accumulated in a glycosidically-bound form and gallic acid was the main metabolite. Green tea contained more soluble phenols and phenolic acids but less quercetin. In vitro experiments with Drosera spathulata revealed that nitrogen deficiency enhances PAL activity, accumulation of phenols and sugars while PAL inhibitor (2-aminoindane-2-phosphonic acid) depleted phenols and some amino acids (but free phenylalanine and sugars were elevated). Possible explanations in physiological, biochemical and ecological context are discussed. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  19. A novel ammonia-oxidizing archaeon from wastewater treatment plant: Its enrichment, physiological and genomic characteristics

    Science.gov (United States)

    Li, Yuyang; Ding, Kun; Wen, Xianghua; Zhang, Bing; Shen, Bo; Yang, Yunfeng

    2016-03-01

    Ammonia-oxidizing archaea (AOA) are recently found to participate in the ammonia removal processes in wastewater treatment plants (WWTPs), similar to their bacterial counterparts. However, due to lack of cultivated AOA strains from WWTPs, their functions and contributions in these systems remain unclear. Here we report a novel AOA strain SAT1 enriched from activated sludge, with its physiological and genomic characteristics investigated. The maximal 16S rRNA gene similarity between SAT1 and other reported AOA strain is 96% (with “Ca. Nitrosotenuis chungbukensis”), and it is affiliated with Wastewater Cluster B (WWC-B) based on amoA gene phylogeny, a cluster within group I.1a and specific for activated sludge. Our strain is autotrophic, mesophilic (25 °C–33 °C) and neutrophilic (pH 5.0–7.0). Its genome size is 1.62 Mb, with a large fragment inversion (accounted for 68% genomic size) inside. The strain could not utilize urea due to truncation of the urea transporter gene. The lack of the pathways to synthesize usual compatible solutes makes it intolerant to high salinity (>0.03%), but could adapt to low salinity (0.005%) environments. This adaptation, together with possibly enhanced cell-biofilm attachment ability, makes it suitable for WWTPs environment. We propose the name “Candidatus Nitrosotenuis cloacae” for the strain SAT1.

  20. Ripening Physiology of Fruit from Transgenic Tomato (Lycopersicon esculentum) Plants with Reduced Ethylene Synthesis.

    Science.gov (United States)

    Klee, H. J.

    1993-07-01

    The physiological effects of reduced ethylene synthesis in a transgenic tomato (Lycopersicon esculentum) line expressing 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase enzyme have been examined. Fruit from the transgenic line 5673 ripen significantly slower than control fruit when removed from the vine early in ripening. In contrast, fruit that remain attached to the plants ripen much more rapidly, exhibiting little delay relative to the control. Ethylene determinations on attached fruit revealed that there was significantly more internal ethylene in attached than detached fruit. The higher ethylene content can fully account for the observed faster on-the-vine ripening. All of the data are consistent with a catalytic role for ethylene in promoting many, although not all, aspects of fruit ripening. Biochemical analyses of transgenic fruit indicated no significant differences from controls in the levels of ACC oxidase or polygalacturonase. Because transgenic fruit are significantly firmer than controls, this last result indicates that other enzymes may have a significant role in fruit softening.

  1. Physiological and biochemical characterization of Azospirillum brasilense strains commonly used as plant growth-promoting rhizobacteria.

    Science.gov (United States)

    Di Salvo, Luciana P; Silva, Esdras; Teixeira, Kátia R S; Cote, Rosalba Esquivel; Pereyra, M Alejandra; García de Salamone, Inés E

    2014-12-01

    Azospirillum is a plant growth-promoting rhizobacteria (PGPR) genus vastly studied and utilized as agriculture inoculants. Isolation of new strains under different environmental conditions allows the access to the genetic diversity and improves the success of inoculation procedures. Historically, the isolation of this genus has been performed by the use of some traditional culture media. In this work we characterized the physiology and biochemistry of five different A. brasilense strains, commonly used as cereal inoculants. The aim of this work is to contribute to pose into revision some concepts concerning the most used protocols to isolate and characterize this bacterium. We characterized their growth in different traditional and non-traditional culture media, evaluated some PGPR mechanisms and characterized their profiles of fatty acid methyl esters and carbon-source utilization. This work shows, for the first time, differences in both profiles, and ACC deaminase activity of A. brasilense strains. Also, we show unexpected results obtained in some of the evaluated culture media. Results obtained here and an exhaustive knowledge revision revealed that it is not appropriate to conclude about bacterial species without analyzing several strains. Also, it is necessary to continue developing studies and laboratory techniques to improve the isolation and characterization protocols.

  2. Effect of cadmium on physiological parameters of cereal and millet plants-A comparative study.

    Science.gov (United States)

    Asopa, Prem Prakash; Bhatt, Ritika; Sihag, Santosh; Kothari, S L; Kachhwaha, Sumita

    2017-03-04

    Metal load is an abiotic stress that becomes stronger by continual industrial production, wastage, and long-range transport of contaminants. It deteriorates the conditions of agricultural soil that leads to lower growth of cereals as well as decreasing nutritional value of harvested grains. Cadmium (Cd) entry by food chain also affects the health of population. The present study is focused on finding out the superior cereal variety under increasing Cd regime. The plants were grown in increasing Cd levels (0-1000 µM) in the medium and were investigated on 15th day of the exposure. Various parameters like antioxidative enzymes and osmoprotectant levels were studied in both roots and shoots. Cd accumulation in plant organs was determined by atomic absorption spectrophotometry (AAS). Analysis of stress tolerance mechanisms through reactive oxygen species (ROS) scavenging and better partitioning of Cd in roots indicated kodo millet to be more stress tolerant than wheat.

  3. Physiological, structural and molecular traits activated in strawberry plants after inoculation with the plant growth-promoting bacterium Azospirillum brasilense REC3.

    Science.gov (United States)

    Guerrero-Molina, M F; Lovaisa, N C; Salazar, S M; Martínez-Zamora, M G; Díaz-Ricci, J C; Pedraza, R O

    2015-05-01

    The plant growth-promoting strain REC3 of Azospirillum brasilense, isolated from strawberry roots, prompts growth promotion and systemic protection against anthracnose disease in this crop. Hence, we hypothesised that A. brasilense REC3 can induce different physiological, structural and molecular responses in strawberry plants. Therefore, the aim of this work was to study these traits activated in Azospirillum-colonised strawberry plants, which have not been assessed until now. Healthy, in vitro micropropagated plants were root-inoculated with REC3 under hydroponic conditions; root and leaf tissues were sampled at different times, and oxidative burst, phenolic compound content, malondialdehyde (MDA) concentration, callose deposition, cell wall fortification and gene expression were evaluated. Azospirillum inoculation enhanced levels of soluble phenolic compounds after 12 h post-inoculation (hpi), while amounts of cell wall bound phenolics were similar in inoculated and control plants. Other early responses activated by REC3 (at 24 hpi) were a decline of lipid peroxidation and up-regulation of strawberry genes involved in defence (FaPR1), bacterial recognition (FaFLS2) and H₂O₂ depuration (FaCAT and FaAPXc). The last may explain the apparent absence of oxidative burst in leaves after bacterial inoculation. Also, REC3 inoculation induced delayed structural responses such as callose deposition and cell wall fortification (at 72 hpi). Results showed that A. brasilense REC3 is capable of exerting beneficial effects on strawberry plants, reinforcing their physiological and cellular characteristics, which in turns contribute to improve plant performance.

  4. Physiological and Proteomic Analysis in Chloroplasts of Solanum lycopersicum L. under Silicon Efficiency and Salinity Stress

    Directory of Open Access Journals (Sweden)

    Sowbiya Muneer

    2014-11-01

    Full Text Available Tomato plants often grow in saline environments in Mediterranean countries where salt accumulation in the soil is a major abiotic stress that limits its productivity. However, silicon (Si supplementation has been reported to improve tolerance against several forms of abiotic stress. The primary aim of our study was to investigate, using comparative physiological and proteomic approaches, salinity stress in chloroplasts of tomato under silicon supplementation. Tomato seedlings (Solanum lycopersicum L. were grown in nutrient media in the presence or absence of NaCl and supplemented with silicon for 5 days. Salinity stress caused oxidative damage, followed by a decrease in silicon concentrations in the leaves of the tomato plants. However, supplementation with silicon had an overall protective effect against this stress. The major physiological parameters measured in our studies including total chlorophyll and carotenoid content were largely decreased under salinity stress, but were recovered in the presence of silicon. Insufficient levels of net-photosynthesis, transpiration and stomatal conductance were also largely improved by silicon supplementation. Proteomics analysis of chloroplasts analyzed by 2D-BN-PAGE (second-dimensional blue native polyacrylamide-gel electrophoresis revealed a high sensitivity of multiprotein complex proteins (MCPs such as photosystems I (PSI and II (PSII to the presence of saline. A significant reduction in cytochrome b6/f and the ATP-synthase complex was also alleviated by silicon during salinity stress, while the complex forms of light harvesting complex trimers and monomers (LHCs were rapidly up-regulated. Our results suggest that silicon plays an important role in moderating damage to chloroplasts and their metabolism in saline environments. We therefore hypothesize that tomato plants have a greater capacity for tolerating saline stress through the improvement of photosynthetic metabolism and chloroplast proteome

  5. Physiological and proteomic analysis in chloroplasts of Solanum lycopersicum L. under silicon efficiency and salinity stress.

    Science.gov (United States)

    Muneer, Sowbiya; Park, Yoo Gyeong; Manivannan, Abinaya; Soundararajan, Prabhakaran; Jeong, Byoung Ryong

    2014-11-26

    Tomato plants often grow in saline environments in Mediterranean countries where salt accumulation in the soil is a major abiotic stress that limits its productivity. However, silicon (Si) supplementation has been reported to improve tolerance against several forms of abiotic stress. The primary aim of our study was to investigate, using comparative physiological and proteomic approaches, salinity stress in chloroplasts of tomato under silicon supplementation. Tomato seedlings (Solanum lycopersicum L.) were grown in nutrient media in the presence or absence of NaCl and supplemented with silicon for 5 days. Salinity stress caused oxidative damage, followed by a decrease in silicon concentrations in the leaves of the tomato plants. However, supplementation with silicon had an overall protective effect against this stress. The major physiological parameters measured in our studies including total chlorophyll and carotenoid content were largely decreased under salinity stress, but were recovered in the presence of silicon. Insufficient levels of net-photosynthesis, transpiration and stomatal conductance were also largely improved by silicon supplementation. Proteomics analysis of chloroplasts analyzed by 2D-BN-PAGE (second-dimensional blue native polyacrylamide-gel electrophoresis) revealed a high sensitivity of multiprotein complex proteins (MCPs) such as photosystems I (PSI) and II (PSII) to the presence of saline. A significant reduction in cytochrome b6/f and the ATP-synthase complex was also alleviated by silicon during salinity stress, while the complex forms of light harvesting complex trimers and monomers (LHCs) were rapidly up-regulated. Our results suggest that silicon plays an important role in moderating damage to chloroplasts and their metabolism in saline environments. We therefore hypothesize that tomato plants have a greater capacity for tolerating saline stress through the improvement of photosynthetic metabolism and chloroplast proteome expression

  6. Diagnostics of subtropical plants functional state by cluster analysis

    Directory of Open Access Journals (Sweden)

    Oksana Belous

    2016-05-01

    Full Text Available The article presents an application example of statistical methods for data analysis on diagnosis of the adaptive capacity of subtropical plants varieties. We depicted selection indicators and basic physiological parameters that were defined as diagnostic. We used evaluation on a set of parameters of water regime, there are: determination of water deficit of the leaves, determining the fractional composition of water and detection parameters of the concentration of cell sap (CCS (for tea culture flushes. These settings are characterized by high liability and high responsiveness to the effects of many abiotic factors that determined the particular care in the selection of plant material for analysis and consideration of the impact on sustainability. On the basis of the experimental data calculated the coefficients of pair correlation between climatic factors and used physiological indicators. The result was a selection of physiological and biochemical indicators proposed to assess the adaptability and included in the basis of methodical recommendations on diagnostics of the functional state of the studied cultures. Analysis of complex studies involving a large number of indicators is quite difficult, especially does not allow to quickly identify the similarity of new varieties for their adaptive responses to adverse factors, and, therefore, to set general requirements to conditions of cultivation. Use of cluster analysis suggests that in the analysis of only quantitative data; define a set of variables used to assess varieties (and the more sampling, the more accurate the clustering will happen, be sure to ascertain the measure of similarity (or difference between objects. It is shown that the identification of diagnostic features, which are subjected to statistical processing, impact the accuracy of the varieties classification. Selection in result of the mono-clusters analysis (variety tea Kolhida; hazelnut Lombardsky red; variety kiwi Monty

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

    Science.gov (United States)

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

    1989-01-01

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

  8. Multiple regression for physiological data analysis: the problem of multicollinearity.

    Science.gov (United States)

    Slinker, B K; Glantz, S A

    1985-07-01

    Multiple linear regression, in which several predictor variables are related to a response variable, is a powerful statistical tool for gaining quantitative insight into complex in vivo physiological systems. For these insights to be correct, all predictor variables must be uncorrelated. However, in many physiological experiments the predictor variables cannot be precisely controlled and thus change in parallel (i.e., they are highly correlated). There is a redundancy of information about the response, a situation called multicollinearity, that leads to numerical problems in estimating the parameters in regression equations; the parameters are often of incorrect magnitude or sign or have large standard errors. Although multicollinearity can be avoided with good experimental design, not all interesting physiological questions can be studied without encountering multicollinearity. In these cases various ad hoc procedures have been proposed to mitigate multicollinearity. Although many of these procedures are controversial, they can be helpful in applying multiple linear regression to some physiological problems.

  9. FPGA-Based Smart Sensor for Drought Stress Detection in Tomato Plants Using Novel Physiological Variables and Discrete Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Carlos Duarte-Galvan

    2014-10-01

    Full Text Available Soil drought represents one of the most dangerous stresses for plants. It impacts the yield and quality of crops, and if it remains undetected for a long time, the entire crop could be lost. However, for some plants a certain amount of drought stress improves specific characteristics. In such cases, a device capable of detecting and quantifying the impact of drought stress in plants is desirable. This article focuses on testing if the monitoring of physiological process through a gas exchange methodology provides enough information to detect drought stress conditions in plants. The experiment consists of using a set of smart sensors based on Field Programmable Gate Arrays (FPGAs to monitor a group of plants under controlled drought conditions. The main objective was to use different digital signal processing techniques such as the Discrete Wavelet Transform (DWT to explore the response of plant physiological processes to drought. Also, an index-based methodology was utilized to compensate the spatial variation inside the greenhouse. As a result, differences between treatments were determined to be independent of climate variations inside the greenhouse. Finally, after using the DWT as digital filter, results demonstrated that the proposed system is capable to reject high frequency noise and to detect drought conditions.

  10. FPGA-based smart sensor for drought stress detection in tomato plants using novel physiological variables and discrete wavelet transform.

    Science.gov (United States)

    Duarte-Galvan, Carlos; Romero-Troncoso, Rene de J; Torres-Pacheco, Irineo; Guevara-Gonzalez, Ramon G; Fernandez-Jaramillo, Arturo A; Contreras-Medina, Luis M; Carrillo-Serrano, Roberto V; Millan-Almaraz, Jesus R

    2014-10-09

    Soil drought represents one of the most dangerous stresses for plants. It impacts the yield and quality of crops, and if it remains undetected for a long time, the entire crop could be lost. However, for some plants a certain amount of drought stress improves specific characteristics. In such cases, a device capable of detecting and quantifying the impact of drought stress in plants is desirable. This article focuses on testing if the monitoring of physiological process through a gas exchange methodology provides enough information to detect drought stress conditions in plants. The experiment consists of using a set of smart sensors based on Field Programmable Gate Arrays (FPGAs) to monitor a group of plants under controlled drought conditions. The main objective was to use different digital signal processing techniques such as the Discrete Wavelet Transform (DWT) to explore the response of plant physiological processes to drought. Also, an index-based methodology was utilized to compensate the spatial variation inside the greenhouse. As a result, differences between treatments were determined to be independent of climate variations inside the greenhouse. Finally, after using the DWT as digital filter, results demonstrated that the proposed system is capable to reject high frequency noise and to detect drought conditions.

  11. Is There a Positive Synergistic Effect of Biochar and Compost Soil Amendments on Plant Growth and Physiological Performance?

    Directory of Open Access Journals (Sweden)

    M. Lukas Seehausen

    2017-02-01

    Full Text Available The combination of biochar (BC with compost has been suggested to be a promising strategy to promote plant growth and performance, but although “synergistic” effects have been stated to occur, full-factorial experiments are few, and explicit tests for synergism are lacking. We tested the hypothesis that a combination of BC and spent mushroom substrate (SMS has a positive synergistic effect on plant growth and physiological performance in a nutrient-limited growing media. A greenhouse experiment with a full factorial design was conducted using mixed-wood BC (3.0 kg·m−2 and SMS (1.5 kg·m−2 (the combination was not co-composted as organic soil amendments for the annual Abutilon theophrasti and the perennial Salix purpurea. Several measurements related to plant growth and physiological performance were taken throughout the experiment. Contrary to the hypothesis, we found that the combination of BC + SMS had neutral or antagonistic interactive effects on many plant growth traits. Antagonistic effects were found on maximum leaf area, above- and belowground biomass, reproductive allocation, maximum plant height, chlorophyll fluorescence, and stomatal conductance of A. theophrasti. The effect on S. purpurea was mostly neutral. We conclude that the generalization that BC and compost have synergistic effects on plant performance is not supported.

  12. Invited review: Genomic analysis of data from physiological studies.

    Science.gov (United States)

    Garrick, D J; Baumgard, L H; Neibergs, H L

    2012-02-01

    Physiology deals with the functions of living organisms and their systems, and its scientific endeavors can be viewed as having temporally occurred in 3 phases. The first phase of physiology studies focused on determining the functions of particular organs and tissues and their functional differences according to physiological status. The second phase of studies focused on characterizing differences in these functions according to the environment, or productivity. The third phase of studies focuses on determining the physiological causes of differences in productivity. Distinguishing cause from effect in physiological systems of inter-related processes is problematic, such that science has struggled to identify the root physiological mechanisms and their role in the network of genes leading to differences in productivity. Genomics is the study of the entire genome and provides powerful new tools that will accelerate third-phase discoveries of causal physiological processes. That research exploits information on DNA polymorphisms known as markers, complete DNA sequence, RNA sequence, and RNA expression in particular tissues at specific life stages. Physiologists can determine the genetic cause of mutant animals, identify genetic differences between cases and controls, and identify genes responsible for differences in performance between average and above-average animals. In some species, physiologists can leverage genomic data being used to predict genetic merit in elite seedstock populations, as a starting point to identify genes that will then motivate detailed physiological studies in the organs or tissues and stages of life in which those genes are expressed. Such work will increase our knowledge of biology and may lead to novel approaches to manipulate animal performance.

  13. Relating nutritional and physiological characteristics to growth of Pinus radiata clones planted on a range of sites in New Zealand.

    Science.gov (United States)

    Hawkins, Barbara J; Xue, Jianming; Bown, Horacio E; Clinton, Peter W

    2010-09-01

    Six clones of radiata pine with known differences in growth rate were examined for clonal nutritional characteristics and for physiological determinants of clonal growth rate. We compared growth, foliar characteristics and nutrient, ¹³C and ¹⁵N concentration data for the six clones in 4- to 6-year-old field trials planted over a range of nutritionally contrasting sites. These data were also compared with growth, nutrient uptake and remobilization, foliar characteristic and gas exchange data from intensive physiological glasshouse experiments using 1- and 2-year-old plants of the same clones. Significant genotype x environment interactions in our field experiments conducted over strong nutritional gradients allowed us to identify radiata pine clones with consistent, superior growth and nutritional characteristics and clones that may be suited to particular site conditions. Our results suggest that the opportunity exists to exploit clone x site variation for site-specific clonal deployment and planting of fast-growing clones could be accompanied by planting of clones able to take relative advantage of site nutritional characteristics. Faster tree growth was not strongly related to any physiological characteristic, and the factors influencing growth rate differed among clones. The fastest-growing clone had consistent, high uptake of all nutrients, high fascicle weights and high water-use efficiency.

  14. Physiological Integration Affects Expansion of an Amphibious Clonal Plant from Terrestrial to Cu-Polluted Aquatic Environments

    Science.gov (United States)

    Xu, Liang; Zhou, Zhen-Feng

    2017-01-01

    The effects of physiological integration on clonal plants growing in aquatic and terrestrial habitats have been extensively studied, but little is known about the role in the extension of amphibious clonal plants in the heterogeneous aquatic-terrestrial ecotones, especially when the water environments are polluted by heavy metals. Ramets of the amphibious clonal herb Alternanthera philoxeroides were rooted in unpolluted soil and polluted water at three concentrations of Cu. The extension of populations from unpolluted terrestrial to polluted aqueous environments mainly relied on stem elongation rather than production of new ramets. The absorbed Cu in the ramets growing in polluted water could be spread horizontally to other ramets in unpolluted soil via physiological integration and redistributed in different organs. The performances of ramets in both terrestrial and aquatic habitats were negatively correlated with Cu intensities in different organs of plants. It is concluded that physiological integration might lessen the fitness of connected ramets in heterogeneously polluted environments. The mechanical strength of the stems decreased with increasing Cu levels, especially in polluted water. We suggest that, except for direct toxicity to growth and expansion, heavy metal pollution might also increase the mechanical risk in breaking failure of plants. PMID:28272515

  15. Physiological Integration Affects Expansion of an Amphibious Clonal Plant from Terrestrial to Cu-Polluted Aquatic Environments

    Science.gov (United States)

    Xu, Liang; Zhou, Zhen-Feng

    2017-03-01

    The effects of physiological integration on clonal plants growing in aquatic and terrestrial habitats have been extensively studied, but little is known about the role in the extension of amphibious clonal plants in the heterogeneous aquatic-terrestrial ecotones, especially when the water environments are polluted by heavy metals. Ramets of the amphibious clonal herb Alternanthera philoxeroides were rooted in unpolluted soil and polluted water at three concentrations of Cu. The extension of populations from unpolluted terrestrial to polluted aqueous environments mainly relied on stem elongation rather than production of new ramets. The absorbed Cu in the ramets growing in polluted water could be spread horizontally to other ramets in unpolluted soil via physiological integration and redistributed in different organs. The performances of ramets in both terrestrial and aquatic habitats were negatively correlated with Cu intensities in different organs of plants. It is concluded that physiological integration might lessen the fitness of connected ramets in heterogeneously polluted environments. The mechanical strength of the stems decreased with increasing Cu levels, especially in polluted water. We suggest that, except for direct toxicity to growth and expansion, heavy metal pollution might also increase the mechanical risk in breaking failure of plants.

  16. Model development and calibration for investigating climate, soil, and plant physiological controls on desert ecosystems

    Science.gov (United States)

    Ng, G. C.; Bedford, D.; Miller, D. M.

    2011-12-01

    Arid ecosystems have adapted to cope with extreme temperatures and unreliable moisture inputs. Understanding desert vegetation dynamics through seasonal to inter-annual meteorological variability is important for assessing how further intensification of the hydrological system under climate change may impact desert ecosystems. Furthermore, due to world-wide problems with desertification, proper ecological characterization of deserts, which already cover a fifth of the world's land surface, is increasingly critical for monitoring global-scale ecology. We present a model-based study that examines spatio-temporal dynamics of desert vegetation in a research watershed located in the Mojave Desert. Moving from the basin floor to higher elevations, the study area covers a range of meteorological and soil conditions, allowing us to explore how various climate, soil, and plant physiological factors interact to affect desert ecosystems. The first stage of this work entails developing a model appropriate for simulating desert ecological systems. NCAR's CLM-CN model fully couples dynamics within the soil-vegetation-atmosphere continuum. It includes parameterizations for diverse vegetation types, making it a flexible and accessible tool for ecohydrological studies. The dominant plant-type in our study area is Larrea tridentata, a shrub abundantly found in deserts of North and South America. We find that the current CLM-CN sub-model for (semi-)arid region shrubs may not be suitable for the extreme conditions found in parts of the study area. Model modifications representing various adaptations of drought-resistant Larrea are crucial for properly simulating vegetation growth. Changes to CLM's soil hydraulic property functions are also needed to represent gravelly soils typical of the region. After developing a suitable parameterization for desert shrubs and soils, we calibrate the model to soil moisture and vegetation measurements in the study area. This includes soil moisture

  17. A developmental biologist’s journey to rediscover the Zen of plant physiology [v1; ref status: indexed, http://f1000r.es/53n

    OpenAIRE

    José R Dinneny

    2015-01-01

    Physiology, which is often viewed as a field of study distinct from development, is technically defined as the branch of biology that explores the normal function of living organisms and their parts. Because plants normally develop continuously throughout their life, plant physiology actually encompasses all developmental processes. Viewing plant biology from a physiologist’s perspective is an attempt to understand the interconnectedness of development, form, and function in the context of mu...

  18. Evaluating the physiological state of maize (Zea mays L.) plants by direct-injection electrospray mass spectrometry (DIESI-MS).

    Science.gov (United States)

    García-Flores, Martín; Juárez-Colunga, Sheila; Montero-Vargas, Josaphat Miguel; López-Arciniega, Janet Ana Isabel; Chagolla, Alicia; Tiessen, Axel; Winkler, Robert

    2012-06-01

    Climatic change is an increasing challenge for agriculture that is driving the development of suitable crops in order to ensure supply for both human nutrition and animal feed. In this context, it is increasingly important to understand the biochemical responses of cells to environmental cues at the whole system level, an aim that is being brought closer by advances in high throughput, cost-efficient plant metabolomics. To support molecular breeding activities, we have assessed the economic, technical and statistical feasibility of using direct mass spectrometry methods to evaluate the physiological state of maize (Zea mays L.) plants grown under different stress conditions.

  19. Effect of Various Doses Application of Metribuzin Herbicide and Plant Density on Yield and Physiological Indices of Wheat (Triticum aestivum

    Directory of Open Access Journals (Sweden)

    M Naghshbandi

    2012-10-01

    Full Text Available In order to survey the influence of metribuzin herbicide on physiological indices and yield of wheat, an experiment was conducted at experimental field of Plant Pest and Disease Research Institute, Karaj, Iran during 2007. Treatments were in factorial arrangement laid out in four randomized complete blocks. The factors investigated were three plant densities: 400, 500 and 600 plant.m-2 and metribuzin doses: 0, 0.2, 0.4, 0.6 and 0.8 kg.ha-1. The result showed that the highest physiological indices and grain yield were obsevered in densities of 500 plant.m-2 and in applications of 0.6 and 0.8 kg. ha-1. Higher rates could be provided an acceptable level of weed control. Plant density could provide good control on weed and could be decrease using herbicide too by decreasing of available light for weed. This strategy can reduce the peresure of selection in resistant weeds population.

  20. State of the interface between conservation and physiology: a bibliometric analysis

    OpenAIRE

    LENNOX, ROBERT; Cooke, Steven J.

    2014-01-01

    Contemporary conservation science benefits from the perspectives of a variety of different disciplines, including a recent synergy with physiology, an interface known as ‘conservation physiology’. To evaluate the degree of interaction between conservation and animal/plant physiology, we conducted three bibliometric analyses. We first pursued the use of the term ‘conservation physiology’ since its first definition in 2006 to determine how frequently it has been used and in which publications. ...

  1. Physiological characteristics of high yield under cluster planting: photosynthesis and canopy microclimate of cotton

    Directory of Open Access Journals (Sweden)

    Ting-ting Xie

    2016-01-01

    Full Text Available Cotton produces more biomass and economic yield when cluster planting pattern (three plants per hole than in a traditional planting pattern (one plant per hole, even at similar plant densities, indicating that individual plant growth is promoted by cluster planting. The causal factors for this improved growth induced by cluster planting pattern, the light interception, canopy microclimate and photosynthetic rate of cotton were investigated in an arid region of China. The results indicated that the leaf area index and light interception were higher in cluster planting, and significantly different from those in traditional planting during the middle and late growth stages. Cotton canopy humidity at different growth stages was increased but canopy temperatures were reduced by cluster planting. In the later growth stage of cluster planting, the leaf chlorophyll content was higher and the leaf net photosynthetic rate and canopy photosynthetic rate were significantly increased in comparing with traditional planting pattern. We concluded that differences in canopy light interception and photosynthetic rate were the primary factors responsible for increased biomass production and economic yield in cluster planting compared with the traditional planting of cotton.

  2. Physiological studies on cultivar-specific resistance of tomato plants to Cladosporium fulvum

    NARCIS (Netherlands)

    Wit, de P.J.G.M.

    1981-01-01

    Ultrastructural and physiological aspects of cultivar-specific resistance of tomato against Cladosporium fulvum (syn. Fulvia fulva) are subject of this thesis.The ultrastructural study described in the first paper was meant as an introduction to a physiological study of cultivar-specific resistance.

  3. Simple and robust determination of the activity signature of key carbohydrate metabolism enzymes for physiological phenotyping in model and crop plants.

    Science.gov (United States)

    Jammer, Alexandra; Gasperl, Anna; Luschin-Ebengreuth, Nora; Heyneke, Elmien; Chu, Hyosub; Cantero-Navarro, Elena; Großkinsky, Dominik K; Albacete, Alfonso A; Stabentheiner, Edith; Franzaring, Jürgen; Fangmeier, Andreas; van der Graaff, Eric; Roitsch, Thomas

    2015-09-01

    The analysis of physiological parameters is important to understand the link between plant phenotypes and their genetic bases, and therefore is needed as an important element in the analysis of model and crop plants. The activities of enzymes involved in primary carbohydrate metabolism have been shown to be strongly associated with growth performance, crop yield, and quality, as well as stress responses. A simple, fast, and cost-effective method to determine activities for 13 key enzymes involved in carbohydrate metabolism has been established, mainly based on coupled spectrophotometric kinetic assays. The comparison of extraction buffers and requirement for dialysis of crude protein extracts resulted in a universal protein extraction protocol, suitable for the preparation of protein extracts from different organs of various species. Individual published kinetic activity assays were optimized and adapted for a semi-high-throughput 96-well assay format. These assays proved to be robust and are thus suitable for physiological phenotyping, enabling the characterization and diagnosis of the physiological state. The potential of the determination of distinct enzyme activity signatures as part of a physiological fingerprint was shown for various organs and tissues from three monocot and five dicot model and crop species, including two case studies with external stimuli. Differential and specific enzyme activity signatures are apparent during inflorescence development and upon in vitro cold treatment of young inflorescences in the monocot ryegrass, related to conditions for doubled haploid formation. Likewise, treatment of dicot spring oilseed rape with elevated CO2 concentration resulted in distinct patterns of enzyme activity responses in leaves.

  4. A monitoring system of radioactive tracers in hydroponic solution for research on plant physiology

    Energy Technology Data Exchange (ETDEWEB)

    Suzui, N.; Kawachi, N.; Ishioka, N.; Fujimaki, S. [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Takasaki, Gunma 370-1292 (Japan); Yamaguchi, M. [Takasaki Advanced Radiation Research Institute, Atomic Energy Agency, Takasaki, Gunma 370-1292 (Japan)

    2009-07-01

    The mechanism of nutrient uptake in plants has received considerable attention in the field of plant science. Here we describe the development of a new monitoring system of radioactive tracers in hydroponic solution, which enables the noninvasive measurement of radioactive tracer uptake by an intact plant. In addition, we incorporated a weighing instrument into this system in order to simultaneously monitor water uptake by the same plant. For an evaluation of this monitoring system, we conducted a tracer experiment with a rice plant and a positron-emitting radioactive tracer, and successfully obtained continuous data for the amounts of radioactive tracer and water taken up by the intact plant over 36 h. (authors)

  5. Plant physiological, morphological and yield-related responses to night temperature changes across different species and plant functional types

    OpenAIRE

    Panpan Jing; Dan Wang; Chunwu Zhu; Jiquan Chen

    2016-01-01

    Land surface temperature over the past decades has shown a faster warming trend during the night than during the day. Extremely low night temperatures have occurred frequently due to the influence of land-sea thermal difference, topography and climate change. This asymmetric night temperature change is expected to affect plant ecophysiology and growth, as the plant carbon consumption processes could be affected more than the assimilation processes because photosynthesis in most plants occurs ...

  6. An improved quantitative analysis method for plant cortical microtubules.

    Science.gov (United States)

    Lu, Yi; Huang, Chenyang; Wang, Jia; Shang, Peng

    2014-01-01

    The arrangement of plant cortical microtubules can reflect the physiological state of cells. However, little attention has been paid to the image quantitative analysis of plant cortical microtubules so far. In this paper, Bidimensional Empirical Mode Decomposition (BEMD) algorithm was applied in the image preprocessing of the original microtubule image. And then Intrinsic Mode Function 1 (IMF1) image obtained by decomposition was selected to do the texture analysis based on Grey-Level Cooccurrence Matrix (GLCM) algorithm. Meanwhile, in order to further verify its reliability, the proposed texture analysis method was utilized to distinguish different images of Arabidopsis microtubules. The results showed that the effect of BEMD algorithm on edge preserving accompanied with noise reduction was positive, and the geometrical characteristic of the texture was obvious. Four texture parameters extracted by GLCM perfectly reflected the different arrangements between the two images of cortical microtubules. In summary, the results indicate that this method is feasible and effective for the image quantitative analysis of plant cortical microtubules. It not only provides a new quantitative approach for the comprehensive study of the role played by microtubules in cell life activities but also supplies references for other similar studies.

  7. An Improved Quantitative Analysis Method for Plant Cortical Microtubules

    Directory of Open Access Journals (Sweden)

    Yi Lu

    2014-01-01

    Full Text Available The arrangement of plant cortical microtubules can reflect the physiological state of cells. However, little attention has been paid to the image quantitative analysis of plant cortical microtubules so far. In this paper, Bidimensional Empirical Mode Decomposition (BEMD algorithm was applied in the image preprocessing of the original microtubule image. And then Intrinsic Mode Function 1 (IMF1 image obtained by decomposition was selected to do the texture analysis based on Grey-Level Cooccurrence Matrix (GLCM algorithm. Meanwhile, in order to further verify its reliability, the proposed texture analysis method was utilized to distinguish different images of Arabidopsis microtubules. The results showed that the effect of BEMD algorithm on edge preserving accompanied with noise reduction was positive, and the geometrical characteristic of the texture was obvious. Four texture parameters extracted by GLCM perfectly reflected the different arrangements between the two images of cortical microtubules. In summary, the results indicate that this method is feasible and effective for the image quantitative analysis of plant cortical microtubules. It not only provides a new quantitative approach for the comprehensive study of the role played by microtubules in cell life activities but also supplies references for other similar studies.

  8. Effects of Organic and Chemical Fertilizations and Microbe Inoculation on Physiology and Growth ofSweet Corn Plants

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A pot culture experiment was carried out in a glasshouse to compare the physiology and growth of sweet corn plants (Zea mays L. cv. Honey Bantam) grown under organic and chemical fertilizations with or without microbial inoculation (MI). The organic fertilizer used was fermented mainly using rice bran and oil mill sludge, and the MI was a liquid product containing many beneficial microbes such as lactic acid bacteria, yeast, photosynthetic bacteria and actinomycetes. The application amounts of the organic fertilizer and chemical fertilizers were based on the same rate of nitrogen, phosphorus and potassium. Sweet corn plants fertilized with organic materials inoculated with beneficial microbes grew better than those without inoculation. There were no significant differences in physiology and growth of the sweet corn plants between treatments of chemical fertilizers with and without MI. Among the organic fertilization treatments, only the sweet corn plants with organic fertilizer and MI applied 4 weeks before sowing had similar photosynthetic capacity, total dry matter yield and ear yield to those with chemical fertilizers. Sweet corn plants in other organic fertilization treatments were weaker in physiology and growth than those in chemical fertilization treatments. There was no significant variance among chemical fertilization treatments at different time. It is concluded from this research that this organic fertilizer would be more effective if it was inoculated with the beneficial microbes. Early application of the organic fertilizer with beneficial microbes before sowing was recommended to make the nutrients available before the rapid growth at the early stage and obtain a yield similar to or higher than that with chemical fertilizations.

  9. Comparative analysis of twelve Dothideomycete plant pathogens

    Energy Technology Data Exchange (ETDEWEB)

    Ohm, Robin; Aerts, Andrea; Salamov, Asaf; Goodwin, Stephen B.; Grigoriev, Igor

    2011-03-11

    The Dothideomycetes are one of the largest and most diverse groups of fungi. Many are plant pathogens and pose a serious threat to agricultural crops grown for biofuel, food or feed. Most Dothideomycetes have only a single host and related Dothideomycete species can have very diverse host plants. Twelve Dothideomycete genomes have currently been sequenced by the Joint Genome Institute and other sequencing centers. They can be accessed via Mycocosm which has tools for comparative analysis

  10. Efficacy of Physiologically Active Anti-Transpirants on Excised Leaves of Potted Plants

    NARCIS (Netherlands)

    Besufkad Degif, A.; Woltering, E.J.

    2015-01-01

    Pot plant production in the greenhouse is most of the time under high relative humidity and frequent irrigation. While, during shipping and retailing plants may be exposed to high temperature and infrequent irrigation. These unfavorable conditions often cause water loss, desiccation of plants and sh

  11. Non-linear effects of drought under shade: reconciling physiological and ecological models in plant communities

    NARCIS (Netherlands)

    Holmgren, M.; Gomez-Aparicio, L.; Quero, J.L.; Valladares, F.

    2012-01-01

    The combined effects of shade and drought on plant performance and the implications for species interactions are highly debated in plant ecology. Empirical evidence for positive and negative effects of shade on the performance of plants under dry conditions supports two contrasting theoretical model

  12. The effect of dehydration on plant regeneration and some physiology characters in rice calli

    Institute of Scientific and Technical Information of China (English)

    ZHAOChengzhang; WULianbin; YANGChangdeng; QIXiufang

    1997-01-01

    The plant regeneration frequencies of calli from plant tissue and cell culture, especially that of the calli from rice tissue culture and rice anther culture, and that of the foreign-DNA-transfor-matlon-derived rice calli is very low (usually 10-15%). It is therefor very important to improve the plant regeneration frequency of rice calli.

  13. Control of chaos in excitable physiological systems: A geometric analysis.

    Science.gov (United States)

    Christini, David J.; Collins, James J.

    1997-12-01

    Model-independent chaos control techniques are inherently well-suited for the control of physiological systems for which quantitative system models are unavailable. The proportional perturbation feedback (PPF) control paradigm, which uses electrical stimulation to perturb directly the controlled system variable (e.g., the interbeat or interspike interval), was developed for excitable physiological systems that do not have an easily accessible system parameter. We develop the stable manifold placement (SMP) technique, a PPF-type technique which is simpler and more robust than the original PPF control algorithm. We use the SMP technique to control a simple geometric model of a chaotic system in the neighborhood of an unstable periodic orbit (UPO). We show that while the SMP technique can control a chaotic system that has UPO dynamics which are characterized by one stable manifold and one unstable manifold, the success of the SMP technique is sensitive to UPO parameter estimation errors. (c) 1997 American Institute of Physics.

  14. Analytical traceability of melon (Cucumis melo var reticulatus): proximate composition, bioactive compounds, and antioxidant capacity in relation to cultivar, plant physiology state, and seasonal variability.

    Science.gov (United States)

    Maietti, Annalisa; Tedeschi, Paola; Stagno, Caterina; Bordiga, Matteo; Travaglia, Fabiano; Locatelli, Monica; Arlorio, Marco; Brandolini, Vincenzo

    2012-06-01

    Two morphologically different cultivars of Italian melons (Baggio and Giusto) were characterized considering samples harvested in different times, at the beginning (BPP) and at the end of the physiological plant production period (EPP). Proximate composition, protein, minerals, pH, phenolic content, antioxidant capacity, ascorbic acid, carotenoids, condensed tannins, and flavonoids were measured, showing a significant decrease in EPP samples (phenolics, antioxidant capacity, condensed tannins, and flavonoids); ascorbic acid decreased in Giusto cv, carotenoids in Baggio cv. Mineral content increased in either the cultivars (EPP samples). Year-to-year difference was significantly highlighted; the plant growing cycle significantly affected the chemotype. Despite these effects, the Principal Component Analysis (PCA) permitted the discrimination of Baggio from Giusto cv, and the discrimination of BPP from EPP samples as well.

  15. ANALYSIS THE DIURNAL VARIATIONS ON SELECTED PHYSICAL AND PHYSIOLOGICAL PARAMETERS

    Directory of Open Access Journals (Sweden)

    A. MAHABOOBJAN

    2010-12-01

    Full Text Available The purpose of the study was to analyze the diurnal variations on selected physical and physiological parameters such as speed, explosive power, resting heart rate and breath holding time among college students. To achieve the purpose of this study, a total of twenty players (n=20 from Government Arts College, Salem were selected as subjects To study the diurnal variation of the players on selected physiological and performance variables, the data were collected 4 times a day with every four hours in between the times it from 6.00 to 18.00 hours were selected as another categorical variable. One way repeated measures (ANOVA was used to analyze the data. If the obtained F-ratio was significant, Seheffe’s post-hoc test was used to find out the significant difference if anyamong the paired means. The level of significance was fixed at.05 level. It has concluded that both physical and physiological parameters were significantly deferred with reference to change of temperature in a day

  16. Soil organic matter influences cerium translocation and physiological processes in kidney bean plants exposed to cerium oxide nanoparticles.

    Science.gov (United States)

    Majumdar, Sanghamitra; Peralta-Videa, Jose R; Trujillo-Reyes, Jesica; Sun, Youping; Barrios, Ana C; Niu, Genhua; Margez, Juan P Flores-; Gardea-Torresdey, Jorge L

    2016-11-01

    Soil organic matter plays a major role in determining the fate of the engineered nanomaterials (ENMs) in the soil matrix and effects on the residing plants. In this study, kidney bean plants were grown in soils varying in organic matter content and amended with 0-500mg/kg cerium oxide nanoparticles (nano-CeO2) under greenhouse condition. After 52days of exposure, cerium accumulation in tissues, plant growth and physiological parameters including photosynthetic pigments (chlorophylls and carotenoids), net photosynthesis rate, transpiration rate, and stomatal conductance were recorded. Additionally, catalase and ascorbate peroxidase activities were measured to evaluate oxidative stress in the tissues. The translocation factor of cerium in the nano-CeO2 exposed plants grown in organic matter enriched soil (OMES) was twice as the plants grown in low organic matter soil (LOMS). Although the leaf cover area increased by 65-111% with increasing nano-CeO2 concentration in LOMS, the effect on the physiological processes were inconsequential. In OMES leaves, exposure to 62.5-250mg/kg nano-CeO2 led to an enhancement in the transpiration rate and stomatal conductance, but to a simultaneous decrease in carotenoid contents by 25-28%. Chlorophyll a in the OMES leaves also decreased by 27 and 18% on exposure to 125 and 250mg/kg nano-CeO2. In addition, catalase activity increased in LOMS stems, and ascorbate peroxidase increased in OMES leaves of nano-CeO2 exposed plants, with respect to control. Thus, this study provides clear evidence that the properties of the complex soil matrix play decisive roles in determining the fate, bioavailability, and biological transport of ENMs in the environment. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Modifications of Morphometrical and Physiological Parameters of Pepper Plants Grown on Artificial Nutrient Medium for Experiments in Spaceflight

    Science.gov (United States)

    Nechitailo, Galina S.

    2016-07-01

    MODIFICATIONS OF MORPHOMETRICAL AND PHYSIOLOGICAL PARAMETERS OF PEPPER PLANTS GROWN ON ARTIFICIAL NUTRIENT MEDIUM FOR EXPERIMENTS IN SPACEFLIGHT Lui Min*, Zhao Hui*, Chen Yu*, Lu Jinying*, Li Huasheng*, Sun Qiao*, Nechitajlo G.S.**, Glushchenko N.N.*** *Shenzhou Space Biotechnology Group, China Academy of Space Technology (CAST), **Emanuel Institute of Biochemical Physics of Russian Academy of Sciences (IBCP RAS) mail: spacemal@mail.ru ***V.L. Talrose Institute for Energy Problems of Chemical Physics of Russian Academy of Science (INEPCP RAS) mail: nnglu@ mail.ru In circumstances of space flights, long residence of the staff at space stations and space settlements an optimal engineering system of the life-support allowing to solve a number of technical and psychological problems for successful work and a life of cosmonauts, researchers, etc. is important and prime. In this respect it is necessary to consider growing plants on board of spacecraft as one of the units in a life-support system. It is feasible due to modern development of biotechnologies in growing plants allowing us to receive materials with new improved properties. Thus, a composition and ratio of components of nutrient medium can considerably influence on plants properties. We have developed the nutrient medium in which essential metals such as iron, zinc, copper were added in an electroneutral state in the form of nanoparticles instead of sulfates or other salts of the same metals. Such replacement is appropriate through unique nanoparticles properties: metal nanoparticles are less toxic than their corresponding ionic forms; nanoparticles produce a prolonged effect, serving as a depot for elements in an organism; nanoparticles introduced in biotic doses stimulate the metabolic processes of the organism; nanoparticles effect is multifunctional. Pepper strain LJ-king was used for growing on a nutrient medium with ferrous, zinc, copper nanoparticles in different concentrations. Pepper plants grown on

  18. Quantitative analysis of protein turnover in plants.

    Science.gov (United States)

    Nelson, Clark J; Li, Lei; Millar, A Harvey

    2014-03-01

    Proteins are constantly being synthesised and degraded as plant cells age and as plants grow, develop and adapt the proteome. Given that plants develop through a series of events from germination to fruiting and even undertake whole organ senescence, an understanding of protein turnover as a fundamental part of this process in plants is essential. Both synthesis and degradation processes are spatially separated in a cell across its compartmented structure. The majority of protein synthesis occurs in the cytosol, while synthesis of specific components occurs inside plastids and mitochondria. Degradation of proteins occurs in both the cytosol, through the action of the plant proteasome, and in organelles and lytic structures through different protease classes. Tracking the specific synthesis and degradation rate of individual proteins can be undertaken using stable isotope feeding and the ability of peptide MS to track labelled peptide fractions over time. Mathematical modelling can be used to follow the isotope signature of newly synthesised protein as it accumulates and natural abundance proteins as they are lost through degradation. Different technical and biological constraints govern the potential for the use of (13)C, (15)N, (2)H and (18)O for these experiments in complete labelling and partial labelling strategies. Future development of quantitative protein turnover analysis will involve analysis of protein populations in complexes and subcellular compartments, assessing the effect of PTMs and integrating turnover studies into wider system biology study of plants.

  19. Environmental analysis for pipeline gas demonstration plants

    Energy Technology Data Exchange (ETDEWEB)

    Stinton, L.H.

    1978-09-01

    The Department of Energy (DOE) has implemented programs for encouraging the development and commercialization of coal-related technologies, which include coal gasification demonstration-scale activities. In support of commercialization activities the Environmental Analysis for Pipeline Gas Demonstration Plants has been prepared as a reference document to be used in evaluating potential environmental and socioeconomic effects from construction and operation of site- and process-specific projects. Effluents and associated impacts are identified for six coal gasification processes at three contrasting settings. In general, impacts from construction of a high-Btu gas demonstration plant are similar to those caused by the construction of any chemical plant of similar size. The operation of a high-Btu gas demonstration plant, however, has several unique aspects that differentiate it from other chemical plants. Offsite development (surface mining) and disposal of large quantities of waste solids constitute important sources of potential impact. In addition, air emissions require monitoring for trace metals, polycyclic aromatic hydrocarbons, phenols, and other emissions. Potential biological impacts from long-term exposure to these emissions are unknown, and additional research and data analysis may be necessary to determine such effects. Possible effects of pollutants on vegetation and human populations are discussed. The occurrence of chemical contaminants in liquid effluents and the bioaccumulation of these contaminants in aquatic organisms may lead to adverse ecological impact. Socioeconomic impacts are similar to those from a chemical plant of equivalent size and are summarized and contrasted for the three surrogate sites.

  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. Optimal plant water use across temporal scales: bridging eco-hydrological theories and plant eco-physiological responses

    Science.gov (United States)

    Manzoni, S.; Vico, G.; Palmroth, S.; Katul, G. G.; Porporato, A. M.

    2013-12-01

    In terrestrial ecosystems, plant photosynthesis occurs at the expense of water losses through stomata, thus creating an inherent hydrologic constrain to carbon (C) gains and productivity. While such a constraint cannot be overcome, evolution has led to a number of adaptations that allow plants to thrive under highly variable and often limiting water availability. It may be hypothesized that these adaptations are optimal and allow maximum C gain for a given water availability. A corollary hypothesis is that these adaptations manifest themselves as coordination between the leaf photosynthetic machinery and the plant hydraulic system. This coordination leads to functional relations between the mean hydrologic state, plant hydraulic traits, and photosynthetic parameters that can be used as bridge across temporal scales. Here, optimality theories describing the behavior of stomata and plant morphological features in a fluctuating soil moisture environment are proposed. The overarching goal is to explain observed global patterns of plant water use and their ecological and biogeochemical consequences. The problem is initially framed as an optimal control problem of stomatal closure during drought of a given duration, where maximizing the total photosynthesis under limited and diminishing water availability is the objective function. Analytical solutions show that commonly used transpiration models (in which stomatal conductance is assumed to depend on soil moisture) are particular solutions emerging from the optimal control problem. Relations between stomatal conductance, vapor pressure deficit, and atmospheric CO2 are also obtained without any a priori assumptions under this framework. Second, the temporal scales of the model are expanded by explicitly considering the stochasticity of rainfall. In this context, the optimal control problem becomes a maximization problem for the mean photosynthetic rate. Results show that to achieve maximum C gains under these

  2. Plant biostimulants: physiological responses induced by protein hydrolyzed-based products and humic substances in plant metabolism

    Directory of Open Access Journals (Sweden)

    Serenella Nardi

    2016-02-01

    Full Text Available ABSTRACT In recent years, the use of biostimulants in sustainable agriculture has been growing. Biostimulants can be obtained from different organic materials and include humic substances (HS, complex organic materials, beneficial chemical elements, peptides and amino acids, inorganic salts, seaweed extracts, chitin and chitosan derivatives, antitranspirants, amino acids and other N-containing substances. The application of biostimulants to plants leads to higher content of nutrients in their tissue and positive metabolic changes. For these reasons, the development of new biostimulants has become a focus of scientific interest. Among their different functions, biostimulants influence plant growth and nitrogen metabolism, especially because of their content in hormones and other signalling molecules. A significant increase in root hair length and density is often observed in plants treated with biostimulants, suggesting that these substances induce a “nutrient acquisition response” that favors nutrient uptake in plants via an increase in the absorptive surface area. Furthermore, biostimulants positively influence the activity and gene expression of enzymes functioning in the primary and secondary plant metabolism. This article reviews the current literature on two main classes of biostimulants: humic substances and protein-based biostimulants. The characteristic of these biostimulants and their effects on plants are thoroughly described.

  3. Biochemical and physiological characterisation of the purine degradation pathway in plants

    OpenAIRE

    Werner, Andrea

    2013-01-01

    Plant growth is often limited by nitrogen availability in the soil. Not only do plants depend on efficient nitrogen uptake, they also require effective means to internally redistribute nitrogen during every stage of development. The purine degradation pathway contributes to this nitrogen recycling in plants. In tropical legumes it is also of central importance to the plants’ nitrogen supply under nitrogen-fixing conditions. This is the first time that the complete ureide degradation pathway h...

  4. Plant stress analysis technology deployment

    Energy Technology Data Exchange (ETDEWEB)

    Ebadian, M.A.

    1998-01-01

    Monitoring vegetation is an active area of laser-induced fluorescence imaging (LIFI) research. The Hemispheric Center for Environmental Technology (HCET) at Florida International University (FIU) is assisting in the transfer of the LIFI technology to the agricultural private sector through a market survey. The market survey will help identify the key eco-agricultural issues of the nations that could benefit from the use of sensor technologies developed by the Office of Science and Technology (OST). The principal region of interest is the Western Hemisphere, particularly, the rapidly growing countries of Latin America and the Caribbean. The analysis of needs will assure that the focus of present and future research will center on economically important issues facing both hemispheres. The application of the technology will be useful to the agriculture industry for airborne crop analysis as well as in the detection and characterization of contaminated sites by monitoring vegetation. LIFI airborne and close-proximity systems will be evaluated as stand-alone technologies and additions to existing sensor technologies that have been used to monitor crops in the field and in storage.

  5. Physiological and molecular implications of plant polyamine metabolism during biotic interactions

    Directory of Open Access Journals (Sweden)

    Juan Francisco Jiménez Bremont

    2014-03-01

    Full Text Available During ontogeny, plants interact with a wide variety of microorganisms. The association with mutualistic microbes results in benefits for the plant. By contrast, pathogens may cause a remarkable impairment of plant growth and development. Both types of plant-microbe interactions provoke notable changes in the polyamine (PA metabolism of the host and/or the microbe, being each interaction a complex and dynamic process. It has been well documented that the levels of free and conjugated PAs undergo profound changes in plant tissues during the interaction with microorganisms. In general, this is correlated with a precise and coordinated regulation of PA biosynthetic and catabolic enzymes. Interestingly, some evidence suggests that the relative importance of these metabolic pathways may depend on the nature of the microorganism, a concept that stems from the fact that these amines mediate the activation of plant defense mechanisms. This effect is mediated mostly through PA oxidation, even though part of the response is activated by non-oxidized PAs. In the last years, a great deal of effort has been devoted to profile plant gene expression following microorganism recognition. In addition, the phenotypes of transgenic and mutant plants in PA metabolism genes have been assessed. In this review, we integrated the current knowledge on this field and analyze the possible roles of these amines during the interaction of plants with microbes.

  6. Genetic Analysis of Digestive Physiology Using Fluorescent Phospholipid Reporters

    Science.gov (United States)

    Farber, Steven A.; Pack, Michael; Ho, Shiu-Ying; Johnson, Iain D.; Wagner, Daniel S.; Dosch, Roland; Mullins, Mary C.; Hendrickson, H. Stewart; Hendrickson, Elizabeth K.; Halpern, Marnie E.

    2001-05-01

    Zebrafish are a valuable model for mammalian lipid metabolism; larvae process lipids similarly through the intestine and hepatobiliary system and respond to drugs that block cholesterol synthesis in humans. After ingestion of fluorescently quenched phospholipids, endogenous lipase activity and rapid transport of cleavage products results in intense gall bladder fluorescence. Genetic screening identifies zebrafish mutants, such as fat free, that show normal digestive organ morphology but severely reduced phospholipid and cholesterol processing. Thus, fluorescent lipids provide a sensitive readout of lipid metabolism and are a powerful tool for identifying genes that mediate vertebrate digestive physiology.

  7. Effects of narrow plant spacing on root distribution and physiological nitrogen use efficiency in summer maize

    Directory of Open Access Journals (Sweden)

    Wenshun Jiang

    2013-10-01

    Full Text Available The objective of this study was to understand the effects of plant spacing on grain yield and root competition in summer maize (Zea mays L.. Maize cultivar Denghai 661 was planted in rectangular tanks (0.54 m × 0.27 m × 1.00 m under 27 cm (normal and 6 cm (narrow plant spacing and treated with zero and 7.5 g nitrogen (N per plant. Compared to normal plant spacing, narrow plant spacing generated less root biomass in the 0–20 cm zone under both N rates, slight reductions of dry root weight in the 20–40 cm and 40–70 cm zones at the mid-grain filling stage, and slight variation of dry root weights in the 70–100 cm zone during the whole growth period. Narrow plant spacing decreased root reductive activity in all root zones, especially at the grain-filling stage. Grain yield and above-ground biomass were 5.0% and 8.4% lower in the narrow plant spacing than with normal plant spacing, although narrow plant spacing significantly increased N harvest index and N use efficiency in both grain yield and biomass, and higher N translocation rates from vegetative organs. These results indicate that the reductive activity of maize roots in all soil layers and dry weights of shallow roots were significantly decreased under narrow plant spacing conditions, resulting in lower root biomass and yield reduction at maturity. Therefore, a moderately dense sowing is a basis for high yield in summer maize.

  8. Effects of narrow plant spacing on root distribution and physiological nitrogen use efficiency in summer maize

    Institute of Scientific and Technical Information of China (English)

    Wenshun; Jiang; Kongjun; Wang; Qiuping; Wu; Shuting; Dong; Peng; Liu; Jiwang; Zhang

    2013-01-01

    The objective of this study was to understand the effects of plant spacing on grain yield and root competition in summer maize(Zea mays L.). Maize cultivar Denghai 661 was planted in rectangular tanks(0.54 m × 0.27 m × 1.00 m) under 27 cm(normal) and 6 cm(narrow) plant spacing and treated with zero and 7.5 g nitrogen(N) per plant. Compared to normal plant spacing, narrow plant spacing generated less root biomass in the 0–20 cm zone under both N rates, slight reductions of dry root weight in the 20–40 cm and 40–70 cm zones at the mid-grain filling stage, and slight variation of dry root weights in the 70–100 cm zone during the whole growth period. Narrow plant spacing decreased root reductive activity in all root zones, especially at the grain-filling stage. Grain yield and above-ground biomass were 5.0% and 8.4% lower in the narrow plant spacing than with normal plant spacing, although narrow plant spacing significantly increased N harvest index and N use efficiency in both grain yield and biomass, and higher N translocation rates from vegetative organs. These results indicate that the reductive activity of maize roots in all soil layers and dry weights of shallow roots were significantly decreased under narrow plant spacing conditions, resulting in lower root biomass and yield reduction at maturity. Therefore, a moderately dense sowing is a basis for high yield in summer maize.

  9. Modelling grass digestibility on the basis of morphological and physiological plant characteristics

    NARCIS (Netherlands)

    Groot, J.C.J.

    1999-01-01

    Grass digestibility is determined by the rate of plant development, mass of plant organs (leaf blades, leaf sheaths and stem internodes) and composition of organs. The development of an integrating model for grass digestibility necessitates the quantification of developmental

  10. Physiology and toxicology of hormone-disrupting chemicals in higher plants.

    Science.gov (United States)

    Couée, Ivan; Serra, Anne-Antonella; Ramel, Fanny; Gouesbet, Gwenola; Sulmon, Cécile

    2013-06-01

    Higher plants are exposed to natural environmental organic chemicals, associated with plant-environment interactions, and xenobiotic environmental organic chemicals, associated with anthropogenic activities. The effects of these chemicals result not only from interaction with metabolic targets, but also from interaction with the complex regulatory networks of hormone signaling. Purpose-designed plant hormone analogues thus show extensive signaling effects on gene regulation and are as such important for understanding plant hormone mechanisms and for manipulating plant growth and development. Some natural environmental chemicals also act on plants through interference with the perception and transduction of endogenous hormone signals. In a number of cases, bioactive xenobiotics, including herbicides that have been designed to affect specific metabolic targets, show extensive gene regulation effects, which are more in accordance with signaling effects than with consequences of metabolic effects. Some of these effects could be due to structural analogies with plant hormones or to interference with hormone metabolism, thus resulting in situations of hormone disruption similar to animal cell endocrine disruption by xenobiotics. These hormone-disrupting effects can be superimposed on parallel metabolic effects, thus indicating that toxicological characterisation of xenobiotics must take into consideration the whole range of signaling and metabolic effects. Hormone-disruptive signaling effects probably predominate when xenobiotic concentrations are low, as occurs in situations of residual low-level pollutions. These hormone-disruptive effects in plants may thus be of importance for understanding cryptic effects of low-dosage xenobiotics, as well as the interactive effects of mixtures of xenobiotic pollutants.

  11. Morphological and Physiological Plant Responses to Drought Stress in Thymus citriodorus

    Directory of Open Access Journals (Sweden)

    Zdzislaw Attila Tátrai

    2016-01-01

    Full Text Available Water availability is considered as a determinant factor that affects plant growth. The commercial medicinal values of an aromatic plant rely on the presence of secondary metabolites that are affected under water shortage. Two-year-old Thymus citriodorus plants were subjected to different polyethylene glycol (PEG-6000 levels (0, 2%, and 4% under greenhouse condition. PEG treatment lasted for 15 days. Thyme plant showed a morphological drought avoidance mechanism by maintaining the root system development through shoot fresh weight reduction resulting in promoted root absorption capacity and sustained plant growth. Moreover, stressed plants were able to maintain water use efficiency and root : shoot ratio suggesting a strong relation between root water uptake and water use saving strategies. Furthermore, thyme plants reduced tissue dehydration through stomatal closure and improved root water uptake. Content of volatile oil constituents of geraniol and diisobutyl phthalate increased upon drought stress while pseudophytol was reduced. Unexpectedly, thymol was not reported as a main oil element under either control or mild stress condition, while it was increased upon high drought stress in measure of 4.4%. Finally, carvacrol significantly accumulated under high drought stress (+31.7% as compared to control plants.

  12. Substantial roles of hexokinase and fructokinase in the effects of sugars on plant physiology and development.

    Science.gov (United States)

    Granot, David; Kelly, Gilor; Stein, Ofer; David-Schwartz, Rakefet

    2014-03-01

    The basic requirements for plant growth are light, CO2, water, and minerals. However, the absorption and utilization of each of these requires investment on the part of the plant. The primary products of plants are sugars, and the hexose sugars glucose and fructose are the raw material for most of the metabolic pathways and organic matter in plants. To be metabolized, hexose sugars must first be phosphorylated. Only two families of enzymes capable of catalysing the essential irreversible phosphorylation of glucose and fructose have been identified in plants, hexokinases (HXKs) and fructokinases (FRKs). These hexose-phosphorylating enzymes appear to coordinate sugar production with the abilities to absorb light, CO2, water, and minerals. This review describes the long- and short-term effects mediated by HXK and FRK in various tissues, as well as the role of these enzymes in the coordination of sugar production with the absorption of light, CO2, water, and minerals.

  13. Casuarina root exudates alter the physiology, surface properties, and plant infectivity of Frankia sp. strain CcI3.

    Science.gov (United States)

    Beauchemin, Nicholas J; Furnholm, Teal; Lavenus, Julien; Svistoonoff, Sergio; Doumas, Patrick; Bogusz, Didier; Laplaze, Laurent; Tisa, Louis S

    2012-01-01

    The actinomycete genus Frankia forms nitrogen-fixing symbioses with 8 different families of actinorhizal plants, representing more than 200 different species. Very little is known about the initial molecular interactions between Frankia and host plants in the rhizosphere. Root exudates are important in Rhizobium-legume symbiosis, especially for initiating Nod factor synthesis. We measured differences in Frankia physiology after exposure to host aqueous root exudates to assess their effects on actinorhizal symbioses. Casuarina cunninghamiana root exudates were collected from plants under nitrogen-sufficient and -deficient conditions and tested on Frankia sp. strain CcI3. Root exudates increased the growth yield of Frankia in the presence of a carbon source, but Frankia was unable to use the root exudates as a sole carbon or energy source. Exposure to root exudates caused hyphal "curling" in Frankia cells, suggesting a chemotrophic response or surface property change. Exposure to root exudates altered Congo red dye binding, which indicated changes in the bacterial surface properties at the fatty acid level. Fourier transform infrared spectroscopy (FTIR) confirmed fatty acid changes and revealed further carbohydrate changes. Frankia cells preexposed to C. cunninghamiana root exudates for 6 days formed nodules on the host plant significantly earlier than control cells. These data support the hypothesis of early chemical signaling between actinorhizal host plants and Frankia in the rhizosphere.

  14. Physiological effects of magnetite (Fe3O4) nanoparticles on perennial ryegrass (Lolium perenne L.) and pumpkin (Cucurbita mixta) plants.

    Science.gov (United States)

    Wang, Huanhua; Kou, Xiaoming; Pei, Zhiguo; Xiao, John Q; Shan, Xiaoquan; Xing, Baoshan

    2011-03-01

    To date, knowledge gaps and associated uncertainties remain unaddressed on the effects of nanoparticles (NPs) on plants. This study was focused on revealing some of the physiological effects of magnetite (Fe(3)O(4)) NPs on perennial ryegrass (Lolium perenne L.) and pumpkin (Cucurbita mixta cv. white cushaw) plants under hydroponic conditions. This study for the first time reports that Fe(3)O(4) NPs often induced more oxidative stress than Fe(3)O(4) bulk particles in the ryegrass and pumpkin roots and shoots as indicated by significantly increased: (i) superoxide dismutase and catalase enzyme activities, and (ii) lipid peroxidation. However, tested Fe(3)O(4) NPs appear unable to be translocated in the ryegrass and pumpkin plants. This was supported by the following data: (i) No magnetization was detected in the shoots of either plant treated with 30, 100 and 500 mg l(-1) Fe(3)O(4) NPs; (ii) Fe K-edge X-ray absorption spectroscopic study confirmed that the coordination environment of Fe in these plant shoots was similar to that of Fe-citrate complexes, but not to that of Fe(3)O(4) NPs; and (iii) total Fe content in the ryegrass and pumpkin shoots treated with Fe(3)O(4) NPs was not significantly increased compared to that in the control shoots.

  15. Understanding the Biological Roles of Pectins in Plants through Physiological and Functional Characterizations of Plant and Fungal Mutants

    DEFF Research Database (Denmark)

    Stranne, Maria

    wall acetylation (Chapter 2), identification of a candidate gene required for acetylation of pectin (Chapter 3), screening of pectin mutants for susceptibility to the nectrotrophic fungal pathogen Botrytis cinerea (Chapter 4), and identification and functional characterization of an arabinan......-degrading enzyme secreted by B. cinerea during infection of plants (Chapter 5). The results described resulted in valuable new knowledge regarding the role of pectin acetylation and arabinosylation in the model plant Arabidopsis thaliana documented in three published research papers, one manuscript and one...

  16. Plant physiological response of strawberry fruit to chlorine dioxide gas treatment during postharvest storage

    Science.gov (United States)

    Chlorine dioxide, a strong oxidizing and sanitizing agent, is used as a postharvest sanitizer for fruits and vegetables and generally applied on a packing line using a chlorine dioxide generator. The objective of this research was to study the physiological responses of strawberries to ClO2 when app...

  17. Linking Leaf Chlorophyll Fluorescence Properties to Physiological Responses for Stress Detection in Coastal Plant Species

    Science.gov (United States)

    2007-01-01

    temperature and light. Stress may be apparent in morphological and physiological character- istics, which represent integrated responses to multiple...australis (Cav.) Trin. ex Steud. (common reed), Poaceae , is an invasive perennial grass that has formed numerous large colonies, fringing freshwater and...EP, Guntenspergen GR, Brown JJ, Nelson SG (2006) Salt tolerance and osmotic adjustment of Spartina alterniflora ( Poaceae ) and the invasive M

  18. Influence of Environmental Changes on Physiology and Development of Polar Vascular Plants

    Science.gov (United States)

    Giełwanowska, Irena; Pastorczyk, Marta; Kellmann-Sopyła, Wioleta

    2011-01-01

    Polar vascular plants native to the Arctic and the Antarctic geobotanical zone have been growing and reproducing effectively under difficult environmental conditions, colonizing frozen ground areas formerly covered by ice. Our macroscopic observations and microscopic studies conducted by means of a light microscope (LM) and transmission electron microscope (TEM) concerning the anatomical and ultrastructural observations of vegetative and generative tissue in Cerastium arcticum, Colobanthus quitensis, Silene involucrata, plants from Caryophyllaceae and Deschampsia antarctica, Poa annua and Poa arctica, from Poaceae family. In the studies, special attention was paid to plants coming from diversity habitats where stress factors operated with clearly different intensity. In all examinations plants, differences in anatomy were considerable. In Deschampsia antarctica the adaxial epidermis of hairgrass leaves from a humid microhabitat, bulliform cells differentiated. Mesophyll was composed of cells of irregular shapes and resembled aerenchyma. The ultrastructural observations of mesophyll in all plants showed tight adherence of chloroplasts, mitochondria and peroxisomes, surface deformations of these organelles and formation of characteristic outgrowths and pocket concavities filled with cytoplasm with vesicles and organelles by chloroplasts. In reproduction biology of examined Caryophyllaceae and Poaceae plants growing in natural conditions, in the Arctic and in the Antarctic, and in a greenhouse in Olsztyn showed that this plant develops two types of bisexual flowers. Almost all ovules developed and formed seeds with a completely differentiated embryo both under natural conditions in the Arctic and the Antarctic and in a greenhouse in Olsztyn.

  19. Calcium signaling in plant endosymbiotic organelles: mechanism and role in physiology.

    Science.gov (United States)

    Nomura, Hironari; Shiina, Takashi

    2014-07-01

    Recent studies have demonstrated that chloroplasts and mitochondria evoke specific Ca(2+) signals in response to biotic and abiotic stresses in a stress-dependent manner. The identification of Ca(2+) transporters and Ca(2+) signaling molecules in chloroplasts and mitochondria implies that they play roles in controlling not only intra-organellar functions, but also extra-organellar processes such as plant immunity and stress responses. It appears that organellar Ca(2+) signaling might be more important to plant cell functions than previously thought. This review briefly summarizes what is known about the molecular basis of Ca(2+) signaling in plant mitochondria and chloroplasts.

  20. Relationships between xylem embolism and eco-physiological indices in eight woody plants in sltu(Ⅱ):The relationship with photosynthetic eco-physiological indices

    Institute of Scientific and Technical Information of China (English)

    AN Feng; CAI Jing; JIANG Zaimin; ZHANG Yuanying; ZHAO Pingjuan; ZHANG Shuoxin

    2007-01-01

    The relationship between xylem embolism and eco-physiology indices (I.e.photosynthetic available radiation,temperature,relative humidity,photosynthetic rate,transpiration rate,stomatal conductance and water use efficiency) in eight tree species was investigated in situ.The species studied,Robinia pseudoacacia L.,Acer truncatum Bge.,Hippophae rhamnoides L.,Ulmus pumila L.,Pinus tabulaeformis Carr., Pinus bungeana Zucc.ex Endl.,Ligustrum lucidum Ait.,and Salix matsudana Koidz.f.pendula Schneid,grow well on the Xilin campus of Northwest A&F University.Results indicated that photosynthetic available radiation,air temperature and relative humidity can affect xylem embolism by daily adjustment of stomatal conductance,transpiration rate and water relations of a tree.Embolism was a common case in the daily growth of the plants,and there was some correlation between xylem embolism and photosynthetic rate,transpiration rate,stornatal conductance,and water use efficiency.Embolism may thus be an adaptive mechanism by some tree species to water stress.

  1. Recent Advances in the Role of the Elongator Complex in Plant Physiology and tRNA Modiifcation:A Review

    Institute of Scientific and Technical Information of China (English)

    YAN Xu; JIN Xiao-huan; WANG You-mei; ZHENG Bo; CHEN Peng

    2014-01-01

    The Elongator complex is a multifunction protein complex which has been shown to be involved in transcriptional elongation, DNA replication and repair, tubulin and histone acetylation, gene silencing and tranfer RNA uridine modiifcation. The composition of the Elongator complex is found to be highly conserved in eukaryotes, protein homologs of various subunits have been identiifed in fungi, plant, animal, and human. Remarkably, mutation in genes encoding the Elongator complex structural components all results in defects of transfer RNA wobble uridine modiifcation, and this function of the Elongator complex is also conserved in eukaryotes. The Elongator complex mutants in higher plants have pleiotropic phenotypes including defects in vegetative growth, abiscisic acid hypersensitivity, elevated tolerance to drought and oxidative stress. What is the relationship between the Elongator complex’s function in nucleoside modiifcation and its activity in other cellular pathways? This review summarizes the recent advances in study of function of the Elongator complex, in the aspects of cell physiology and molecular biology.

  2. Physiological responses of Vetiver plant (Vetiver zizanioides) to municipal waste leachate

    National Research Council Canada - National Science Library

    Sasan Mohsenzadeh; Nadereh Naderi; Mahdi Nazari

    2016-01-01

    Vetiver plant is tolerant to acidity and temperature variations. Has rapid growth for biomass production and has high tolerance to organic and non-organic compounds in municipal waste leachate for example heavy metals...

  3. Diverse Functional Roles of Monosaccharide Transporters and their Homologs in Vascular Plants: A Physiological Perspective

    Institute of Scientific and Technical Information of China (English)

    Thomas L. Slewinski

    2011-01-01

    Vascular plants contain two gene families that encode monosaccharide transporter proteins. The classical monosaccharide transporter(-like)gene superfamily is large and functionally diverse, while the recently identified SWEET transporter family is smaller and, thus far, only found to transport glucose. These transporters play essential roles at many levels, ranging from organelles to the whole plant. Many family members are essential for cellular homeostasis and re-productive success. Although most transporters do not directly participate in long-distance transport, their indirect roles greatly impact carbon allocation and transport flux to the heterotrophic tissues of the plant. Functional characterization of some members from both gene families has revealed their diverse roles in carbohydrate partitioning, phloem function,resource allocation, plant defense, and sugar signaling. This review highlights the broad impacts and implications of monosaccharide transport by describing some of the functional roles of the monosaccharide transporter(-like)superfamily and the SWEET transporter family.

  4. Physiological and Genetic Bases of the Circadian Clock in Plants and Their Relationship with Herbicides Efficacy

    OpenAIRE

    DALAZEN,G.; Merotto Jr.,A.

    2016-01-01

    In order to adapt to daily environmental changes, especially in relation to light availability, many organisms, such as plants, developed a vital mechanism that controls time-dependent biological events: the circadian clock. The circadian clock is responsible for predicting the changes that occur in the period of approximately 24 hours, preparing the plants for the following phases of the cycle. Some of these adaptations can influence the response of weeds to the herbicide application. Thus, ...

  5. Ways of signal transmission and physiological role of electrical potentials in plants

    Directory of Open Access Journals (Sweden)

    Halina Dziubińska

    2011-01-01

    Full Text Available Plants are subject to stimuli from the environment on which they strongly depend and in contrast to animals, they are unable to escape harmful influences. Therefore, being able to receive stimuli they have developed adequate responses to them. Such a reaction can occur in the area of a stimulus action or cover the whole plant or its parts. In the latter case, it is a systemic reaction. The plant reaction is expressed by various intensity, rate and kind of response. It is interesting to know the character of the signal informing about a stimulus, the routes of its propagation and the transmission mechanism. Three conceptions of excitation are distinguished: 1 propagation of chemical agents formed at the site of a stimulus action with the flow of the phloem sap or through the atmosphere (in the case of volatile substances to other plant parts, 2 a very fast transmission by the xylem in the wave of hydraulic pressure formed after a plant damage. From combining the "hydraulic" and "chemical" hypothesis a conception of hydraulic dispersion has been formulated which assumes that chemical substances synthetized after an injury can be transferred very fast with the wave of hydraulic pressure changes in the whole plant, 3 a stimulus evokes the action potential (AP, and its transmission along the whole plant, plant organ or specialized tissue, by local circuits from cell to cell. Strong, damaging stimuli can evoke variation potentials (VPs, the character of which differs from APs. It is postulated that transmission of VP occurs by a hydraulic dispersion and electrical changes seem to be secondary phenomena.

  6. INTERACTIVE EFFECTS OF SALINITY STRESS AND NICOTINAMIDE ON PHYSIOLOGICAL AND BIOCHEMICAL PARAMETERS ON FABA BEAN PLANT

    Directory of Open Access Journals (Sweden)

    Magdi T. Abdelhamid

    2013-09-01

    Full Text Available A possible survival strategy of plants under saline conditions is to use some compounds that could alleviate salt stress effect. One of these compounds is nicotinamide. The effect of exogenously application of nicotinamide with different concentrations (0, 200 and 400 mg/l on Vicia faba L. plant against different NaCl treatments (0, 50 and 100 mM NaCl was investigated at the wire house of the National Research Centre, Cairo, Egypt. Salinity stress reduced significantly plant height, dry weight of shoot, photosynthetic pigments, polysaccharides, total carbohydrates, total-N contents of shoot, seed yield, total carbohydrates & total crude protein of the yielded seeds compared with those of the control plants. In contrast, salinity induced marked increases in sucrose, total soluble sugars, total free amino acids, proline, lipid peroxidation product (MDA and some oxidative enzymes (polyphenol oxidase and peroxidase enzymes. Also, salinity stress increased Na+ contents with the decreases of other macro and micro elements contents (P, K+, Mg+, Ca2+, Fe2+, Mn2+, Zn2+ and Cu2+ of shoots and the yielded seeds of faba bean. Foliar spraying of nicotinamide alleviated the adverse effects of salinity stress through increased plant height, dry weight of shoot, photosynthetic pigments, polysaccharides, total carbohydrates, total-N contents of shoot and seed yield as well as, sucrose, total soluble sugars, total free amino acids and proline, compared with those of the corresponding salinity levels, while decreased lipid peroxidation product as MDA and the oxidative enzymes (polyphenol oxidase and peroxidase enzymes. Nicotinamide inhibited the uptake of Na+ and accelerated the accumulation of P, K+ , Mg+, Ca2+, Fe2+, Mn2+, Zn2+ and Cu2+ contents in the shoots of salt stressed plants and enhanced total carbohydrate and total crude protein percentage and solutes concentrations in seeds of salinity treated plants

  7. Exergoeconomic analysis of a cogeneration plant

    Energy Technology Data Exchange (ETDEWEB)

    Mert, Mehmet Selcuk [Yalova University, Energy Systems Engineering Department (Turkey)], email: msmert@yalova.edu.tr; Dilmac, Omer Faruk; Ozkan, Semra; Bolat, Esen [Yildiz Technical University Chemical Engineering Department (Turkey)], email: omerfarukdl@yahoo.com, email: ozkans@yildiz.edu.tr, email: ebolat@yildiz.edu.tr

    2011-07-01

    Cogeneration, or combined heat and power, is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat generally in the form of steam or hot water. By capturing the excess heat, it uses thermal energy that would be wasted in a conventional power plant, provides high energy conversion efficiency, and also reduces emissions. Exergy analysis has been found to be an effective tool for predicting the efficiencies of system components and the total thermodynamic effectiveness of the system, as well as for highlighting possible improvements. By using both exergy concepts and economics, an exergoeconomic analysis is possible which helps designers to find ways to improve the performance of a system in a cost effective way. This study presents the exergoeconomic analysis of a cogeneration plant at Erdemir, Turkey. The mass, energy and exergy balances were done, and the exergoeconomic analysis of the plant, with a 39.5 MW electricity total net power and 20.83 kg/s steam production capacity, was also done.

  8. Exergoeconomic analysis of a nuclear power plant

    Science.gov (United States)

    Moreno, Roman Miguel

    Exergoeconomic analysis of a nuclear power plant is a focus of this dissertation. Specifically, the performance of the Palo Verde Nuclear Power Plant in Arizona is examined. The analysis combines thermodynamic second law exergy analysis with economics in order to assign costs to the loss and destruction of exergy. This work was done entirely with an interacting spreadsheets notebook. The procedures are to first determine conventional energy flow, where the thermodynamic stream state points are calculated automatically. Exergy flow is then evaluated along with destruction and losses. The capital cost and fixed investment rate used for the economics do not apply specifically to the Palo Verde Plant. Exergy costing is done next involving the solution of about 90 equations by matrix inversion. Finally, the analysis assigns cost to the exergy destruction and losses in each component. In this work, the cost of electricity (exergy), including capital cost, leaving the generator came to 38,400 /hr. The major exergy destruction occurs in the reactor where fission energy transfer is limited by the maxiμm permissible clad temperature. Exergy destruction costs were: reactor--18,207 hr, the low pressure turbine-2,000 /hr, the condenser--1,700 hr, the steam generator-1,200 $/hr. The inclusion of capital cost and O&M are important in new system design assessments. When investigating operational performance, however, these are sunk costs; only fuel cost needs to be considered. The application of a case study is included based on a real modification instituted at Palo Verde to reduce corrosion steam generator problems; the pressure in the steam generator was reduced from 1072 to 980 psi. Exergy destruction costs increased in the low pressure turbine and in the steam generator, but decreased in the reactor vessel and the condenser. The dissertation demonstrates the procedures and tools required for exergoeconomic analysis whether in the evaluation of a new nuclear reactor system

  9. Physiological and Molecular Analysis of Applied Nitrogen in Rice Genotypes

    Institute of Scientific and Technical Information of China (English)

    Khalid Rehman HAKEEM; Ruby CHANDNA; Altaf AHMAD; Muhammad IQBAL

    2012-01-01

    Ten genotypes of rice (Oryza sativa L.) were grown for 30 d in complete nutrient solution with 1 mmol/L (N-insufficient),4 mmol/L (N-moderate) and 10 mmol/L (N-high) nitrogen levels,and nitrogen efficiency (NE) was analyzed.Growth performance,measured in terms of fresh weight,dry weight and lengths of root and shoot,was higher in N-efficient than in N-inefficient rice genotypes at low N level.Of these 10 genotypes,Suraksha was identified as the most N-efficient,while Vivek Dhan the most N-inefficient.To find out the physiological basis of this difference,the nitrate uptake rate of root and the activities of nitrate assimilatory enzymes in leaves of N-efficient and N-inefficient rice genotypes were studied.Uptake experiments revealed the presence of two separate nitrate transporter systems mediating high- and low-affinity nitrate uptake.Interestingly,the nitrate uptake by the roots of Suraksha is mediated by both high- and low-affinity nitrate transporter systems,while that of Vivek Dhan by only low-affinity nitrate transporter system.Study of the activities and expression levels of nitrate assimilatory enzymes in N-efficient and N-inefficient rice genotypes showed that nitrate reductase (NR) and glutamine svnthetase (GS) play important roles in N assimilation under low-nitrogen conditions.

  10. Research progress on the use of plant allelopathy in agriculture and the physiological and ecological mechanisms of allelopathy

    Directory of Open Access Journals (Sweden)

    Fang eCheng

    2015-11-01

    Full Text Available Allelopathy is a common biological phenomenon by which one organism produces biochemicals that influence the growth, survival, development, and reproduction of other organisms. These biochemicals are known as allelochemicals and have beneficial or detrimental effects on target organisms. Plant allelopathy is one of the modes of interaction between receptor and donor plants and may exert either positive effects (e.g., for agricultural management, such as weed control, crop protection, or crop re-establishment or negative effects (e.g., autotoxicity, soil sickness, or biological invasion. To ensure sustainable agricultural development, it is important to exploit cultivation systems that take advantage of the stimulatory / inhibitory influence of allelopathic plants to regulate plant growth and development and to avoid allelopathic autotoxicity. Allelochemicals can potentially be used as growth regulators, herbicides, insecticides and antimicrobial crop protection products. Here, we reviewed the plant allelopathy management practices applied in agriculture and the underlying allelopathic mechanisms described in the literature. The major points addressed are as follows: (1 Description of management practices related to allelopathy and allelochemicals in agriculture. (2 Discussion of the progress regarding the mode of action of allelochemicals and the physiological mechanisms of allelopathy, consisting of the influence on cell micro- and ultra-structure, cell division and elongation, membrane permeability, oxidative and antioxidant systems, growth regulation systems, respiration, enzyme synthesis and metabolism, photosynthesis, mineral ion uptake, protein and nucleic acid synthesis. (3 Evaluation of the effect of ecological mechanisms exerted by allelopathy on microorganisms and the ecological environment. (4 Discussion of existing problems and proposal for future research directions in this field to provide a useful reference for future studies on

  11. Research Progress on the use of Plant Allelopathy in Agriculture and the Physiological and Ecological Mechanisms of Allelopathy.

    Science.gov (United States)

    Cheng, Fang; Cheng, Zhihui

    2015-01-01

    Allelopathy is a common biological phenomenon by which one organism produces biochemicals that influence the growth, survival, development, and reproduction of other organisms. These biochemicals are known as allelochemicals and have beneficial or detrimental effects on target organisms. Plant allelopathy is one of the modes of interaction between receptor and donor plants and may exert either positive effects (e.g., for agricultural management, such as weed control, crop protection, or crop re-establishment) or negative effects (e.g., autotoxicity, soil sickness, or biological invasion). To ensure sustainable agricultural development, it is important to exploit cultivation systems that take advantage of the stimulatory/inhibitory influence of allelopathic plants to regulate plant growth and development and to avoid allelopathic autotoxicity. Allelochemicals can potentially be used as growth regulators, herbicides, insecticides, and antimicrobial crop protection products. Here, we reviewed the plant allelopathy management practices applied in agriculture and the underlying allelopathic mechanisms described in the literature. The major points addressed are as follows: (1) Description of management practices related to allelopathy and allelochemicals in agriculture. (2) Discussion of the progress regarding the mode of action of allelochemicals and the physiological mechanisms of allelopathy, consisting of the influence on cell micro- and ultra-structure, cell division and elongation, membrane permeability, oxidative and antioxidant systems, growth regulation systems, respiration, enzyme synthesis and metabolism, photosynthesis, mineral ion uptake, protein and nucleic acid synthesis. (3) Evaluation of the effect of ecological mechanisms exerted by allelopathy on microorganisms and the ecological environment. (4) Discussion of existing problems and proposal for future research directions in this field to provide a useful reference for future studies on plant

  12. Effect of various soil salinity level on the antioxidant and physiological properties of corn plant (Zea mays

    Directory of Open Access Journals (Sweden)

    Ramin Ezzati

    2015-10-01

    Full Text Available To study the effect of various soil salinity levels on the antioxidant enzymes and physiological characteristics of corn as an indicator of salt stress resistance, present study was conducted in 2013 at Research lab of environmental, Faculty of Biological Sciences, University of Kharazmi, Iran. Furthermore, desert soils of Libya, India, Iraq and Karaj were used for testing the effect of soil salinity on the quantity of oxidant enzymes and various properties of maize plant. For providing favorable atmospheric conditions 33000 lux light and spray of perlite medium was used. Corn crop is highly sensitive to soil salinity so all the cultivation was carried out under conditions of soil EC lower than 20 ds/m and 8.5 pH. Results of the study revealed that the salt stress significantly affect the amount of antioxidant enzymes such as guaiacol peroxidase and malondialdehyde. Furthermore, it was reported that saline soil did not have any negative effect on the physiological characteristics and growth of corn plant growth.

  13. Physiological responses of macaúba young plants to cyclical drought conditions

    Directory of Open Access Journals (Sweden)

    Clenilso Sehnen Mota

    2016-09-01

    Full Text Available The objective of this study was to evaluate the impact of three cycles of drought/irrigation on the quantum yields of chlorophyll a fluorescence, proline accumulation and osmotic adjustment. Ten plants were submitted to three consecutive cycles of drought/irrigation (D/I and the other ten were maintained at field capacity.Cycles D/I did not promote osmotic adjustment in plants with suspension of irrigation (WSI, despite the proline accumulation. The minimum fluorescence adapted to dark increased and the maximum quantum efficiency of PSII was reduced in WSI plants. Quantum yield of photochemical energy conversion of photosystem II (PSII and the apparent rate of electron transport decreased, while quantum yield dissipation regulated non-photochemical energy in PSII showed an increase in WSI plants over those without suspension of irrigation (WOSI. Quantum yield of no regulated dissipation of PSII non-photochemical energy and chlorophyll and carotenoid content showed no change between WSI and WOSI plants over D/I cycles. Thus it was observed that macaubeira presents an efficient mechanism of non-photochemical energy dissipation.

  14. 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.

  15. Analysis of histones and histone variants in plants.

    Science.gov (United States)

    Trivedi, Ila; Rai, Krishan Mohan; Singh, Sunil Kumar; Kumar, Verandra; Singh, Mala; Ranjan, Amol; Lodhi, Niraj; Sawant, Samir V

    2012-01-01

    Histone proteins are the major protein components of chromatin - the physiologically relevant form of the genome (or epigenome) in all eukaryotic cells. For many years, histones were considered passive structural components of eukaryotic chromatin. In recent years, it has been demonstrated that dynamic association of histones and their variants to the genome plays a very important role in gene regulation. Histones are extensively modified during posttranslation viz. acetylation, methylation, phosphorylation, ubiquitylation, etc., and the identification of these covalent marks on canonical and variant histones is crucial for the understanding of their biological significance. Different biochemical techniques have been developed to purify and separate histone proteins; here, we describe techniques for analysis of histones from plant tissues.

  16. Plant eco-physiological responses to multiple environmental and climate changes

    DEFF Research Database (Denmark)

    Albert, Kristian Rost

    2009-01-01

    The current global changes of temperature, precipitation, atmospheric CO2 and UV-B radiation impact in concert ecosystems and processes in an unpredictable way. Therefore multifactor experimentation is needed to unravel the variability in strength of these drivers, whether the factors act...... interacted. Current UV-B levels decreases productivity in high arctic heath plants, and advanced spring in response to warming may lead to further decrease while other climatic changes as elevated CO2 may negate this. Stimulated productivity of temperate heath plants is likely under the climatic conditions...... additively or synergistically and to establish cause-effect relations between ecosystem processes. This thesis deals with heath plant responses to global change factors (the CLIMAITE project). In a Danish temperate heath ecosystem elevated CO2, experimental summer drought, and passive nighttime warming...

  17. Development of a screening approach for exploring cell factory potential through metabolic flux analysis and physiology

    DEFF Research Database (Denmark)

    Knudsen, Peter Boldsen; Nielsen, Kristian Fog; Thykær, Jette

    2012-01-01

    The recent developments within the field of metabolic engineering have significantly increased the speed by which fungal recombinant strains are being constructed, pushing focus towards physiological characterisation and analysis. This raises demand for a tool for diligent analysis of the recombi...... and work-load connected with screening and selection of potential cell factories with attractive properties, compared with more “traditional” methodologies where metabolic flux analysis is applied at a much later state in the characterisation process.......The recent developments within the field of metabolic engineering have significantly increased the speed by which fungal recombinant strains are being constructed, pushing focus towards physiological characterisation and analysis. This raises demand for a tool for diligent analysis...... on a Hamilton robotic system. This method aimed at characterising physiology at two levels: (1) An approach focusing on the traditional growth related parameters, i.e. growth rate, yield coefficients and extracellular metabolites. (2) 13C-labelling experiments, where metabolic fluxes are quantified...

  18. Cross-spectral analysis of physiological tremor and muscle activity; 2, Application to synchronized EMG

    CERN Document Server

    Timmer, J; Pfleger, W; Deuschl, G

    1998-01-01

    We investigate the relationship between synchronized muscle activity and tremor time series in (enhanced) physiological tremor by cross-spectral analysis. Special attention is directed to the phase spectrum and its possibilities to clarify the contribution of reflex mechanisms to physiological tremor. The phase spectra are investigated under the assumptions that the EMG synchronization was caused by a reflex, respectively a central oscillator. In comparison of these results to phase spectra of measured data we found a significant contribution of reflexes. But reflexes only modify existing peaks in the power spectrum. The main agents of physiological tremor are an efferent pace and the resonant behavior of the biomechanical system.

  19. Physiological response, molecular analysis and water use efficiency ...

    African Journals Online (AJOL)

    SAM

    2014-07-16

    Jul 16, 2014 ... Molecular analysis of three hybrids revealed the possibility of introgressing the ...... complex and depends on both biophysical and economic ... Grant RF, Jackson BS, Kiniry KR, Arkin GF (1989) Water deficit timing effects on ...

  20. Computational Intelligence Techniques for Electro-Physiological Data Analysis

    OpenAIRE

    Riera Sardà, Alexandre

    2012-01-01

    This work contains the efforts I have made in the last years in the field of Electrophysiological data analysis. Most of the work has been done at Starlab Barcelona S.L. and part of it at the Neurodynamics Laboratory of the Department of Psychiatry and Clinical Psychobiology of the University of Barcelona. The main work deals with the analysis of electroencephalography (EEG) signals, although other signals, such as electrocardiography (ECG), electroculography (EOG) and electromiography (EMG) ...

  1. EFFECT OF FOLIAR APPLICATION OF AMINOACIDS ON PLANT YIELD AND PHYSIOLOGICAL PARAMETERS IN FABA BEAN PLANTS IRRIGATED WITH SEAWATER

    Directory of Open Access Journals (Sweden)

    Magdi T. ABDELHAMID

    2014-05-01

    Full Text Available Salinity decreases yield in arid and semi-arid areas. With increasing demand for irrigation water, alternative sources are being sought. Seawater salinity was previously considered unusable for irrigation. However, this water can be used successfully to grow crops under certain conditions. Amino acids is well known biostimulant which has positive effects on plant growth and yield, and significantly mitigates the injuries caused by abiotic stresses Therefore, in the present study, the effect of exogenously treatment amino acid on faba bean plant growing under sea water salt stress was investigated. Reduction of salinity damage in faba bean by using a mixture of amino acids to improve morphological and biochemical parameters, and thus raising the level of plant yield was tested. A pot experiment was conducted to alleviate the harmful effects of seawater salinity on faba bean cv. Giza 843 by foliar spraying of an amino acid mixture with different concentrations (0.0, 500, 1000 or 1500 mg L-1. Irrigation of faba bean plants with seawater levels of 3.13 and 6.25 dS m-1 led to significant reductions in plant height, number of leaves plant, fresh and dry weight of shoots, photosynthetic pigments, total carbohydrates, polysaccharides, nucleic acid DNA and RNA contents of faba bean leaves. Seawater salinity induced higher contents of Na+ and Cl- and decreased contents of K+, K+:Na+, Ca2+, Mg2+ and P3+. Irrigation of faba bean plant with different levels of seawater decreased seed yield and total dry weight per plant compared with those irrigated with tap water. Also, total carbohydrates and total protein contents in seeds were reduced by increased seawater salinity levels. Amino acid application as foliar spray significantly improved all the reduced parameters due to seawater stress. However, the highest level of amino acid of 1500 mg L-1 exerted the strongest effect in alleviating the harmful effect of seawater salinity stress. Efecto de la aplicaci

  2. A versatile physiological data analysis system using an Intel 8080 microprocessor.

    Science.gov (United States)

    Hyde, D; Nice, E G; Oakley, P J

    1979-08-01

    A microprocessor based physiological data processor has been realised. The system controls the data flow from physiological experiments and performs on-line mean and variance calculations with an output in graphical form. The analyser accepts one data point every 0.5 ms and has a capacity of 128 records each containing 800 data points. Post stimulus histogram and interval histogram analysis programs have also been written and implemented.

  3. Models for the physiological effects of short O3 exposures on plants

    NARCIS (Netherlands)

    Schut, H.E.

    1985-01-01

    Some published effects of ozone on plant photosynthesis and evaporation are detailed, and attempts were made to develop explanatory models of increasing complexity. Stomatal regulation, which keeps the CO2 concentration inside the lead constant, is assumed. The O3 concentration inside the leaf is as

  4. MPS/CAS Partner Group on Plant Molecular Physiology and Signal Transduction

    Institute of Scientific and Technical Information of China (English)

    Xue Hongwei; Lothar Willmitzer

    2004-01-01

    @@ Rice is mankind's most important food crop - the staple diet for half of the world's population - and is also tremendously important for Chinese food production.Hence, understanding how rice grows and interacts with its environment, which often adversely affects plant development and crop yield, is of prime importance.

  5. Physiological and biochemical response of plants to engineered NMs: Implications on future design.

    Science.gov (United States)

    de la Rosa, Guadalupe; García-Castañeda, Concepción; Vázquez-Núñez, Edgar; Alonso-Castro, Ángel Josabad; Basurto-Islas, Gustavo; Mendoza, Ángeles; Cruz-Jiménez, Gustavo; Molina, Carlos

    2017-01-01

    Engineered nanomaterials (ENMs) form the basis of a great number of commodities that are used in several areas including energy, coatings, electronics, medicine, chemicals and catalysts, among others. In addition, these materials are being explored for agricultural purposes. For this reason, the amount of ENMs present as nanowaste has significantly increased in the last few years, and it is expected that ENMs levels in the environment will increase even more in the future. Because plants form the basis of the food chain, they may also function as a point-of-entry of ENMs for other living systems. Understanding the interactions of ENMs with the plant system and their role in their potential accumulation in the food chain will provide knowledge that may serve as a decision-making framework for the future design of ENMs. The purpose of this paper was to provide an overview of the current knowledge on the transport and uptake of selected ENMs, including Carbon Based Nanomaterials (CBNMs) in plants, and the implication on plant exposure in terms of the effects at the macro, micro, and molecular level. We also discuss the interaction of ENMs with soil microorganisms. With this information, we suggest some directions on future design and areas where research needs to be strengthened. We also discuss the need for finding models that can predict the behavior of ENMs based on their chemical and thermodynamic nature, in that few efforts have been made within this context. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  6. Timing effects of heat-stress on plant physiological characteristics and growth: a field study with prairie vegetation

    Directory of Open Access Journals (Sweden)

    Dan Wang

    2016-11-01

    Full Text Available More intense, more frequent, and longer heat-waves are expected in the future due to global warming, which could have dramatic agricultural, economic and ecological impacts. This field study examined how plant responded to heat-stress (HS treatment at different timing in naturally-occurring vegetation. HS treatment (5 days at 40.5 ºC were applied to 12 1m2 plots in restored prairie vegetation dominated by Andropogon gerardii (warm-season C4 grass and Solidago canadensis (warm-season C3 forb at different growing stages. During and after HS, air, canopy, and soil temperature were monitored; net CO2 assimilation (Pn, quantum yield of photosystem II (ФPSII, stomatal conductance (gs, and internal CO2 level (Ci of the dominant species were measured. One week after the last HS treatment, all plots were harvested and the biomass of above-ground tissue and flower weight of the two dominant species was determined. HS decreased physiological performance and growth for both species, with S. canadensis being affected more than A. gerardii, indicated by negative heat stress effect on both physiological and growth responses. There were significant timing effect of heat stress on the two species, with greater reductions in the photosynthesis and productivity occurred when heat stress was applied at later-growing season. The reduction in aboveground productivity in S. canadensis but not A. gerardii could have important implications for plant community structure by increasing the competitive advantage of A. gerardii in this grassland. The present experiment showed that heat stress, though ephemeral, may promote long-term effects on plant community structure, vegetation dynamics, biodiversity, and ecosystem functioning of terrestrial biomes when more frequent and severe heat stress occur in the future.

  7. Physiological effects of the air pollutant hydrogen fluoride on phloem transport in soybean plants

    Energy Technology Data Exchange (ETDEWEB)

    Madkour, S.A.A.S.

    1984-01-01

    The effect of continuous exposure to HF at ca. 0, 1, and 5 ugF m/sup -3/ for 8-10 days on the transport and relative distribution of /sup 14/C-labelled photosynthetic assimilates in Hodgson soybean plants at three stages of development (vegetative, flowering and early fruit set, and pod filling) were investigated. Fumigated and non-fumigated plants were supplied with /sup 14/CO/sub 2/ by enclosing the second fully-expanded trifoliolate leaf in a cuvette designed for the purpose. Results from these experiments indicate that transport from the source leaves of /sup 14/C-labelled assimilates to sink tissues was partially inhibited by exposure to both concentrations of HF and at each stage of development. However, the greatest degree of inhibition in the transport occurred in plants that were exposed during the flowering stage. Results indicated that there was a greater retention of sugars and a greater incorporation of the /sup 14/C into non-transport compounds in the source leaves accompanied by a reduced transport to sink tissue as the HF concentration increases. This suggested that F-induced inhibition of phloem loading of sugars. The effect of HF fumigation on phloem loading was investigated by monitoring the uptake of /sup 14/C-sucrose supplied to source leaf discs, collected from fumigated and non-fumigated plants. HF was shown to inhibit the loading of /sup 14/C-sucrose. The effect of F on the activity of plasma membrane ATPase was investigated both in vivo, by isolating plasma membranes from fumigated and non-fumigated plants, and in vitro by exposure of plasma membranes to NaF. F was shown to inhibit ATPase activity both in vivo and in vitro. It is concluded that plasma membrane ATPases is the target site for F inhibition of phloem transport, and that the inhibition occurs through the formation of Mg/sup +2/-fluorophosphate complexes.

  8. Analysis and physiological implications of renal 2-oxoglutaramate metabolism.

    Science.gov (United States)

    Nissim, I; Wehrli, S; States, B; Nissim, I; Yudkoff, M

    1991-07-01

    The relative significance of the flux through the glutamine aminotransferase (glutaminase II) pathway to renal ammoniagenesis is poorly understood. A basic and unresolved question is whether 2-oxoglutaramate (2-OGM), a product of the glutaminase II reaction, is deamidated to yield 2-oxoglutarate and NH3, or whether 2-OGM accumulates as an unreactive lactam, depending on the environmental pH. In the current studies we utilized 13C n.m.r. as well as 15N n.m.r. as well as 15N n.m.r. to demonstrate that 2-OGM occurs as a lactam, i.e. 5-hydroxypyroglutamate, regardless of the environmental pH. Our additional aims were to determine whether human kidney cells (HK cells) in culture can produce 2-OGM and to ascertain a pH-dependent relationship between NH3 and 2-OGM production from glutamine. We therefore developed an isotope dilution assay for 2-OGM utilizing 5-hydroxy[4-13C,1-15N]pyroglutamate as the labelled species. Incubations of HK cells in minimal essential medium supplemented with 1 mM-[2-15N]glutamine demonstrated significantly higher production of 2-OGM at pH 6.8 and lower production at pH 7.6 compared with pH 7.4. Similarly both 15NH3 and [15N]alanine formation were significantly higher in acute acidosis (pH 6.8) and lower in acute alkalosis (pH 7.6) compared with that at physiological pH. Addition of 1 mM-amino-oxyacetate to the incubation medium at pH 7.4 significantly diminished [15N]alanine and 2-OGM production, but the production of 15NH3 via the glutamate dehydrogenase pathway was significantly stimulated. The current observations indicate that the glutaminase II pathway plays a minor role and that flux through glutamate dehydrogenase is the predominant site for regulation of ammoniagenesis in human kidney.

  9. The impact of "physiological correction" on functional connectivity analysis of pharmacological resting state fMRI.

    Science.gov (United States)

    Khalili-Mahani, Najmeh; Chang, Catie; van Osch, Matthias J; Veer, Ilya M; van Buchem, Mark A; Dahan, Albert; Beckmann, Christian F; van Gerven, Joop M A; Rombouts, Serge A R B

    2013-01-15

    Growing interest in pharmacological resting state fMRI (RSfMRI) necessitates developing standardized and robust analytical approaches that are insensitive to spurious correlated physiological signals. However, in pharmacological experiments physiological variations constitute an important aspect of the pharmacodynamic/pharmacokinetic profile of drug action; therefore retrospective corrective methods that discard physiological signals as noise may not be suitable. Previously, we have shown that template-based dual regression analysis is a sensitive method for model-free and objective detection of drug-specific effects on functional brain connectivity. In the current study, the robustness of this standard approach to physiological variations in a placebo controlled, repeated measures pharmacological RSfMRI study of morphine and alcohol in 12 healthy young men is tested. The impact of physiology-related variations on statistical inferences has been studied by: 1) modeling average physiological rates in higher level group analysis; 2) Regressing out the instantaneous respiration variation (RV); 3) applying retrospective image correction (RETROICOR) in the preprocessing stage; and 4) performing combined RV and heart rate correction (RVHRCOR) by regressing out physiological pulses convolved with canonical respiratory and cardiac hemodynamic response functions. Results indicate regional sensitivity of the BOLD signal to physiological variations, especially in the vicinity of large vessels, plus certain brain structures that are reported to be involved in physiological regulation, such as posterior cingulate, precuneus, medial prefrontal and insular cortices, as well as the thalamus, cerebellum and the brainstem. The largest impact of "correction" on final statistical test outcomes resulted from including the average respiration frequency and heart rate in the higher-level group analysis. Overall, the template-based dual regression method seems robust against physical

  10. Physiological and behavioral responses in Drosophila melanogaster to odorants present at different plant maturation stages.

    Science.gov (United States)

    Versace, Elisabetta; Eriksson, Anna; Rocchi, Federico; Castellan, Irene; Sgadò, Paola; Haase, Albrecht

    2016-09-01

    The fruit fly Drosophila melanogaster feeds and oviposits on fermented fruit, hence its physiological and behavioral responses are expected to be tuned to odorants abundant during later stages of fruit maturation. We used a population of about two-hundred isogenic lines of D. melanogaster to assay physiological responses (electroantennograms (EAG)) and behavioral correlates (preferences and choice ratio) to odorants found at different stages of fruit maturation. We quantified electrophysiological and behavioral responses of D. melanogaster for the leaf compound β-cyclocitral, as well as responses to odorants mainly associated with later fruit maturation stages. Electrophysiological and behavioral responses were modulated by the odorant dose. For the leaf compound we observed a steep dose-response curve in both EAG and behavioral data and shallower curves for odorants associated with later stages of maturation. Our data show the connection between sensory and behavioral responses and are consistent with the specialization of D. melanogaster on fermented fruit and avoidance of high doses of compounds associated with earlier stages of maturation. Odor preferences were modulated in a non-additive way when flies were presented with two alternative odorants, and combinations of odorants elicited higher responses than single compounds. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Alkane distribution and carbon isotope composition in fossil leaves: An interpretation of plant physiology in the geologic past

    Science.gov (United States)

    Graham, H. V.; Freeman, K. H.

    2014-12-01

    The relative chain-length distribution and carbon-isotope composition of n-alkanes extracted from sedimentary rocks are important geochemical tools for investigating past terrestrial ecosystems. Alkanes preserved in ancient sediments are assumed to be contemporaneous, derived from the same ecosystem, and integrated from the biomass present on the landscape at the time of deposition. Further, there is an underlying assumption that ancient plants exhibited the same metabolic and physiological responses to climate conditions that are observed for modern plants. Interpretations of alkane abundances and isotopic signatures are complicated by the strong influence of phylogenetic affiliation and ecological factors, such as canopy structure. A better understanding of how ecosystem and taxa influence alkane properties, including homologue abundance patterns and leaf-lipid carbon isotope fractionation would help strengthen paleoecological interpretations based on these widely employed plant biomarkers. In this study, we analyze the alkane chain-length distribution and carbon-isotope composition of phytoleim and alkanes (d13Cleaf and d13Clipid) extracted from a selection of Cretaceous and Paleocene fossil leaves from the Guaduas and Cerrejon Formations of Colombia. These data were compared with data for the same families in a modern analogue biome. Photosynthetic and biosynthetic fractionation (∆leaf and elipid) values determined from the fossil material indicate carbon metabolism patterns were similar to modern plants. Fossil data were incorporated in a biomass-weighted mixing model to represent the expected lipid complement of sediment arising from this ecosystem and compared with alkane measurements from the rock matrix. Modeled and observed isotopic and abundance patterns match well for alkane homologs most abundant in plants (i.e., n-C27 to n-C33). The model illustrates the importance of understanding biases in litter flux and taphonomic pressures inherent in the

  12. Host Plant Physiology and Mycorrhizal Functioning Shift across a Glacial through Future [CO2] Gradient1[OPEN

    Science.gov (United States)

    Mullinix, George W.R.; Ward, Joy K.

    2016-01-01

    Rising atmospheric carbon dioxide concentration ([CO2]) may modulate the functioning of mycorrhizal associations by altering the relative degree of nutrient and carbohydrate limitations in plants. To test this, we grew Taraxacum ceratophorum and Taraxacum officinale (native and exotic dandelions) with and without mycorrhizal fungi across a broad [CO2] gradient (180–1,000 µL L−1). Differential plant growth rates and vegetative plasticity were hypothesized to drive species-specific responses to [CO2] and arbuscular mycorrhizal fungi. To evaluate [CO2] effects on mycorrhizal functioning, we calculated response ratios based on the relative biomass of mycorrhizal (MBio) and nonmycorrhizal (NMBio) plants (RBio = [MBio − NMBio]/NMBio). We then assessed linkages between RBio and host physiology, fungal growth, and biomass allocation using structural equation modeling. For T. officinale, RBio increased with rising [CO2], shifting from negative to positive values at 700 µL L−1. [CO2] and mycorrhizal effects on photosynthesis and leaf growth rates drove shifts in RBio in this species. For T. ceratophorum, RBio increased from 180 to 390 µL L−1 and further increases in [CO2] caused RBio to shift from positive to negative values. [CO2] and fungal effects on plant growth and carbon sink strength were correlated with shifts in RBio in this species. Overall, we show that rising [CO2] significantly altered the functioning of mycorrhizal associations. These symbioses became more beneficial with rising [CO2], but nonlinear effects may limit plant responses to mycorrhizal fungi under future [CO2]. The magnitude and mechanisms driving mycorrhizal-CO2 responses reflected species-specific differences in growth rate and vegetative plasticity, indicating that these traits may provide a framework for predicting mycorrhizal responses to global change. PMID:27573369

  13. Effect of Seed Position on Parental Plant on Proportion of Seeds Produced with Nondeep and Intermediate Physiological Dormancy.

    Science.gov (United States)

    Lu, Juan J; Tan, Dun Y; Baskin, Carol C; Baskin, Jerry M

    2017-01-01

    The position in which seeds develop on the parental plant can have an effect on dormancy-break and germination. We tested the hypothesis that the proportion of seeds with intermediate physiological dormancy (PD) produced in the proximal position on a raceme of Isatis violascens plants is higher than that produced in the distal position, and further that this difference is related to temperature during seed development. Plants were watered at 3-day intervals, and silicles and seeds from the proximal (early) and distal (late) positions of racemes on the same plants were collected separately and tested for germination. After 0 and 6 months dry storage at room temperature (afterripening), silicles and seeds were cold stratified for 0-16 weeks and tested for germination. Mean daily maximum and minimum temperatures during development/maturation of the two groups of seeds did not differ. A higher proportion of seeds with the intermediate level than with the nondeep level of PD was produced by silicles in the proximal position than by those in the distal position, while the proportion of seeds with nondeep PD was higher in the distal than in the proximal position of the raceme. The differences were not due only to seed mass. Since temperature and soil moisture conditions were the same during development of the seeds in the raceme, differences in proportion of seeds with intermediate and nondeep PD are attributed to position on parental plant. The ecological consequence of this phenomenon is that it ensures diversity in dormancy-breaking and germination characteristics within a seed cohort, a probable bet-hedging strategy. This is the first demonstration of position effects on level of PD in the offspring.

  14. Effects of Riyadh cement industry pollutions on some physiological and morphological factors of Datura innoxia Mill. plant.

    Science.gov (United States)

    Salama, Hediat M H; Al-Rumaih, M M; Al-Dosary, M A

    2011-07-01

    Cement factory emissions into air cause serious air pollution and affect the plant and animal life in the environment. Herein, we report the effects of cement industry emissions (O3, SO2 and NO2) in air, as pollutants, at Riyadh City on Datura innoxia Mill. plant. Morphological characters including plant height, leaves area and number, fresh and dry weight of shoot and root systems of D. innoxia showed a significant reduction from their normal control plants as a response to exposure to pollutant emissions. Chlorophyll and carotenoid contents recorded reductions in values compared to control plant, and the lowest values of chlorophyll A, B, total chlorophyll, carotenoids and total pigments were 0.431, 0.169, 0.60, 0.343 and 0.943 mg/g respectively at a distance of 1-5 m from the cement factory in fruiting stage. These changes in values may be attributed to a probable deceleration of the biosynthetic process rather than degradation of pigments. Further D. innoxia showed a significant (P plant. The root system recorded the lowest values of reducing sugars (0.350 mg/g f. wt.), non-reducing sugars (0.116 mg/g f. wt.), total sugars (0.466 mg/g f. wt.), protein content (0.931 mg/g f. wt.) and total lipids content (0.669 mg/g f. wt.) in fruiting stage at a distance of 1-5 m from the cement factory. The peroxidase activity of shoot and root systems of the studied plant was also significantly higher than those of control plant. Thus a highest value of (29.616 units/g f. wt.) peroxidase activity was recorded in vegetative stage of shoot system at a distance 1-5 m from the cement factory. Results of the study indicated that cement industry emission strongly influence the physiology and morphology of date palm D. innoxia which contribute date fruits, a staple food in the Arab world.

  15. Physiological and genetic characterization of plant growth and gravitropism in LED light sources

    Science.gov (United States)

    Deitzer, Gerald F.

    1994-01-01

    Among the many problems of growing plants in completely controlled environments, such as those anticipated for the space station and the CELSS program, is the need to provide light that is both adequate for photosynthesis and of proper quality for normal growth and development. NASA scientists and engineers have recently become interested in the possibility of utilizing densely packed, solid state, light emitting diodes (LED's) as a source for this light. Unlike more conventional incandescent or electrical discharge lamps, these sources are highly monochromatic and lack energy in spectral regions thought to be important for normal plant development. In addition, a recent observation by NASA scientist has suggested that infra-red LED's, that are routinely used as photographic safelights for plants grown in darkness, may interact with the ability of plants to detect gravity. In order to establish how plants respond to light from these LED light sources we carried out a series of experiments with known pigment mutants of the model mustard plant, Arabidopsis thaliana, growing in either a gravity field or on a clinostat to simulate a micro-gravity environment. Results indicate that only red light from the 665 nm LED's disrupts the ability of normal wildtype seedlings to detect a gravity stimulus. There was no consistent effect found for the far-red (735 nm) LED's or either of the infrared (880 nm or 935 nm) LED sources but both showed some effect in one or more of the genotypes tested. Of these five members of the phytochrome multigene family in Arabidopsis, only the phytochrome B pigment mutant (hy3) lacked the ability to detect gravity under all conditions. There was no effect of either micro-gravity (clinostat) or the infra-red LED's on the light induced inhibition of hypocotyl elongation. Measurements of the pigment phytochrome in oats also showed no photoconversion by 15 min irradiations with the infra-red LED's. We conclude that phytochrome B is required for the

  16. Vogtle Electric Generating Plant ETE Analysis Review

    Energy Technology Data Exchange (ETDEWEB)

    Diediker, Nona H.; Jones, Joe A.

    2006-12-09

    Under contract with the Nuclear Regulatory Commission (NRC), staff from Pacific Northwest National Laboratory (PNNL) and Sandia National Laboratory (SNL)-Albuquerque reviewed the evacuation time estimate (ETE) analysis dated April 2006 prepared by IEM for the Vogtle Electric Generating Plant (VEGP). The ETE analysis was reviewed for consistency with federal regulations using the NRC guidelines in Review Standard (RS)-002, Supplement 2 and Appendix 4 to NUREG-0654, and NUREG/CR-4831. Additional sources of information referenced in the analysis and used in the review included NUREG/CR-6863 and NUREG/CR-6864. The PNNL report includes general comments, data needs or clarifications, and requests for additional information (RAI) resulting from review of the ETE analysis.

  17. Spatial variation of eco-physiological parameters in the lichen Pseudevernia furfuracea transplanted in an area surrounding a cement plant (S Italy).

    Science.gov (United States)

    Lucadamo, Lucio; Corapi, Anna; Loppi, Stefano; Paoli, Luca; Gallo, Luana

    2015-08-01

    Thalli of the lichen Pseudevernia furfuracea were transplanted for 3 months (November 2010-January 2011) at 61 monitoring sites around a cement plant near Castrovillari (Calabria, southern Italy). NH3, NO x and SO2 concentrations were monitored monthly in a subarea of 10 sites (SA10) where the cement plant was located. At the end of the exposure period, the integrity of cell membranes; membrane lipid peroxidation (thiobarbituric acid reactive substances, TBARS level); vitality (cell respiration); chlorophyll a; chlorophyll b; carotenoids; phaeophytization quotient; photosynthetic efficiency and thalli concentrations of Al, Ca, Mg, V and Fe were measured. NO x concentrations correlated with the site distance from the cement plant while NH3 concentrations correlated with lichen vitality within SA10. For the monitoring area as a whole, only Fe and Mg concentrations correlated with membrane lipid peroxidation, while TBARS levels showed a significant increase and chlorophyll a, chlorophyll b and carotenoids a significant decrease with respect to the lichen origin area. Multivariate analysis (detrended correspondence analysis, cluster analysis and multi-response permutation procedure) of the eco-physiological parameters × monitoring sites data set resulted in four clusters termed C1, C2, C3 and C4. The eco-physiological parameters were compared among the four clusters and lichen origin area by one-way ANOVA. An index of environmental favourableness (IEF) to lichens was calculated to evaluate the spatial recovery of impaired values of TBARS, chlorophyll a, chlorophyll b, xanthophylls + carotenoids and phaeophytization quotient. The results indicate that there is no clear spatial trend in mycobiont impairment even though the IEF values suggest a higher number of sites with low levels of membrane lipid peroxidation in the 2--3-km distance band from the cement plant (the outermost) than in the two other distance bands (0-1 and 1-2 km). The photobiont seems to be

  18. [Effect of plant growth regulators on physiological activity of Bradyrhizobium japonicum ].

    Science.gov (United States)

    Leonova, N O; Tytova, L V; Tantsiurenko, O V; Antypchuk, A F

    2005-01-01

    Influence of plant growth regulators Ivin, Emistim C, Eney and Agrostimulin on the biomass production and exopolymers synthesis of soybean nodule bacteria, which have contrasting symbiotic properties, and glutamine synthetase activity of their cell-free extracts were studied. It was shown that the processes of the biomass and exopolymers accumulation had an opposite direction. Of all preparations only Ivin and Agrostimulin intensificol growth activity of the microorganisms under study. The level of glutamine synthetase activity and this enzymatic reaction specificity to the bivalent metal ions were determined by the special features of Bradyrhizobium strains and nature of the plant growth regulators. Only in the presence of Eney the increase of glutamine synthetase activity of both cultures of Bradyrhizobium japonicum was established.

  19. Plant eco-physiological responses to multiple environmental and climate changes

    Energy Technology Data Exchange (ETDEWEB)

    Rost Albert, K.

    2009-03-15

    The current global changes of temperature, precipitation, atmospheric CO{sub 2} and UV-B radiation impact in concert ecosystems and processes in an unpredictable way. Therefore multifactor experimentation is needed to unravel the variability in strength of these drivers, whether the factors act additively or synergistically and to establish cause-effect relations between ecosystem processes. This thesis deals with heath plant responses to global change factors (the CLIMAITE project). In a Danish temperate heath ecosystem elevated CO{sub 2}, experimental summer drought, and passive nighttime warming was applied in all combinations (based on the scenario for Denmark anno 2075) and the responses after one year of treatment were investigated through a growing season in Hairgrass (Deschampsia flexousa) and Heather (Calluna vulgaris). In a high arctic heath ecosystem situated in NE-Greenland UV-B exclusion experiments were conducted on Salix arctica and Vaccinium uliginosum during six years. Responses of photosynthesis performance were characterized on the leaf scale by means of leaf gas-exchange (A/Ci curves), chlorophyll-a fluorescence, leaf nitrogen, carbon and delta13C and secondary compounds. The main findings were 1) The different growth strategies of the evergreen Calluna versus the opportunistic bi-phasic Deschampsia affects the photosynthesis response to drought and autumn warming; 2) Elevated CO{sub 2} and warming synergistically increase photosynthesis in spring and autumn; 3) Summer drought decreased photosynthesis in both species, but where Calluna maintained photosynthetic metabolism then major proportion of grass leaves wilted down; 4) Elevated CO{sub 2} did not decrease stomatal conductance, but the treatments affected soil water content positively, pointing to the complex water relations when plants of contrasting growth strategy co-occur; 5) Water availability affected the magnitude of photosynthesis to a higher degree than warming and elevated CO{sub 2

  20. Evolution and challenges of dynamic global vegetation models for some aspects of plant physiology and elevated atmospheric CO2

    Science.gov (United States)

    Rezende, L. F. C.; Arenque, B. C.; Aidar, S. T.; Moura, M. S. B.; Von Randow, C.; Tourigny, E.; Menezes, R. S. C.; Ometto, J. P. H. B.

    2016-07-01

    Dynamic global vegetation models (DGVMs) simulate surface processes such as the transfer of energy, water, CO2, and momentum between the terrestrial surface and the atmosphere, biogeochemical cycles, carbon assimilation by vegetation, phenology, and land use change in scenarios of varying atmospheric CO2 concentrations. DGVMs increase the complexity and the Earth system representation when they are coupled with atmospheric global circulation models (AGCMs) or climate models. However, plant physiological processes are still a major source of uncertainty in DGVMs. The maximum velocity of carboxylation (Vcmax), for example, has a direct impact over productivity in the models. This parameter is often underestimated or imprecisely defined for the various plant functional types (PFTs) and ecosystems. Vcmax is directly related to photosynthesis acclimation (loss of response to elevated CO2), a widely known phenomenon that usually occurs when plants are subjected to elevated atmospheric CO2 and might affect productivity estimation in DGVMs. Despite this, current models have improved substantially, compared to earlier models which had a rudimentary and very simple representation of vegetation-atmosphere interactions. In this paper, we describe this evolution through generations of models and the main events that contributed to their improvements until the current state-of-the-art class of models. Also, we describe some main challenges for further improvements to DGVMs.

  1. Evolution and challenges of dynamic global vegetation models for some aspects of plant physiology and elevated atmospheric CO2.

    Science.gov (United States)

    Rezende, L F C; Arenque, B C; Aidar, S T; Moura, M S B; Von Randow, C; Tourigny, E; Menezes, R S C; Ometto, J P H B

    2016-07-01

    Dynamic global vegetation models (DGVMs) simulate surface processes such as the transfer of energy, water, CO2, and momentum between the terrestrial surface and the atmosphere, biogeochemical cycles, carbon assimilation by vegetation, phenology, and land use change in scenarios of varying atmospheric CO2 concentrations. DGVMs increase the complexity and the Earth system representation when they are coupled with atmospheric global circulation models (AGCMs) or climate models. However, plant physiological processes are still a major source of uncertainty in DGVMs. The maximum velocity of carboxylation (Vcmax), for example, has a direct impact over productivity in the models. This parameter is often underestimated or imprecisely defined for the various plant functional types (PFTs) and ecosystems. Vcmax is directly related to photosynthesis acclimation (loss of response to elevated CO2), a widely known phenomenon that usually occurs when plants are subjected to elevated atmospheric CO2 and might affect productivity estimation in DGVMs. Despite this, current models have improved substantially, compared to earlier models which had a rudimentary and very simple representation of vegetation-atmosphere interactions. In this paper, we describe this evolution through generations of models and the main events that contributed to their improvements until the current state-of-the-art class of models. Also, we describe some main challenges for further improvements to DGVMs.

  2. Plant physiological and soil characteristics associated with methane and nitrous oxide emission from rice paddy

    OpenAIRE

    Baruah, K.K.; Gogoi, Boby; Gogoi, P.

    2010-01-01

    Methane (CH4) and nitrous oxide (N2O) are important greenhouse gases causing global warming and climate change. Efforts were made to analyze the CH4 and N2O flux in relation to plant and soil factors from rice (Oryza sativa L.) paddy. Ten popularly grown rice varieties namely Rashmisali, Bogajoha, Basmuthi, Lalkalamdani, Choimora (traditional varieties); Mahsuri, Moniram, Kushal, Gitesh and Profulla (high yielding varieties = HYV) were grown during monsoon season of July 2006. The CH4 and N2O...

  3. Engineering Triterpene and Methylated Triterpene Production in Plants Provides Biochemical and Physiological Insights into Terpene Metabolism.

    Science.gov (United States)

    Jiang, Zuodong; Kempinski, Chase; Bush, Caroline J; Nybo, S Eric; Chappell, Joe

    2016-02-01

    Linear, branch-chained triterpenes, including squalene (C30), botryococcene (C30), and their methylated derivatives (C31-C37), generated by the green alga Botryococcus braunii race B have received significant attention because of their utility as chemical and biofuel feedstocks. However, the slow growth habit of B. braunii makes it impractical as a production system. In this study, we evaluated the potential of generating high levels of botryococcene in tobacco (Nicotiana tabacum) plants by diverting carbon flux from the cytosolic mevalonate pathway or the plastidic methylerythritol phosphate pathway by the targeted overexpression of an avian farnesyl diphosphate synthase along with two versions of botryococcene synthases. Up to 544 µg g(-1) fresh weight of botryococcene was achieved when this metabolism was directed to the chloroplasts, which is approximately 90 times greater than that accumulating in plants engineered for cytosolic production. To test if methylated triterpenes could be produced in tobacco, we also engineered triterpene methyltransferases (TMTs) from B. braunii into wild-type plants and transgenic lines selected for high-level triterpene accumulation. Up to 91% of the total triterpene contents could be converted to methylated forms (C31 and C32) by cotargeting the TMTs and triterpene biosynthesis to the chloroplasts, whereas only 4% to 14% of total triterpenes were methylated when this metabolism was directed to the cytoplasm. When the TMTs were overexpressed in the cytoplasm of wild-type plants, up to 72% of the total squalene was methylated, and total triterpene (C30+C31+C32) content was elevated 7-fold. Altogether, these results point to innate mechanisms controlling metabolite fluxes, including a homeostatic role for squalene.

  4. Physiological and Anatomical Response of Plant Leaf Tissue to Designated Air Pollutants.

    Science.gov (United States)

    1982-01-07

    of the spongy mesophyll . Alternatively, cells associated with intercellular air chambers immediately beneath stomata may collapse or be disrupted. This...crenalate and plasmolyzed. Cells of the spongy mesophyll 75 were also plasmolyzed. Membrane damage was prevalent in both cell types and the plasmalemma was...and more extensively than palisade or spongy parenchyma cells. Because there are no detailed cytological ultrastructural studies of HCl-fumigated plant

  5. Interaction of plant phenols with food macronutrients: characterisation and nutritional-physiological consequences.

    Science.gov (United States)

    Zhang, Hao; Yu, Dandan; Sun, Jing; Liu, Xianting; Jiang, Lu; Guo, Huiyuan; Ren, Fazheng

    2014-06-01

    Polyphenols are dietary constituents of plants associated with health-promoting effects. In the human diet, polyphenols are generally consumed in foods along with macronutrients. Because the health benefits of polyphenols are critically determined by their bioavailability, the effect of interactions between plant phenols and food macronutrients is a very important topic. In the present review, we summarise current knowledge, with a special focus on the in vitro and in vivo effects of food macronutrients on the bioavailability and bioactivity of polyphenols. The mechanisms of interactions between polyphenols and food macronutrients are also discussed. The evidence collected in the present review suggests that when plant phenols are consumed along with food macronutrients, the bioavailability and bioactivity of polyphenols can be significantly affected. The protein-polyphenol complexes can significantly change the plasma kinetics profile but do not affect the absorption of polyphenols. Carbohydrates can enhance the absorption and extend the time needed to reach a maximal plasma concentration of polyphenols, and fats can enhance the absorption and change the absorption kinetics of polyphenols. Moreover, as highlighted in the present review, not only a nutrient alone but also certain synergisms between food macronutrients have a significant effect on the bioavailability and biological activity of polyphenols. The review emphasises the need for formulations that optimise the bioavailability and in vivo activities of polyphenols.

  6. Tracking Undergraduate Student Achievement in a First-Year Physiology Course Using a Cluster Analysis Approach

    Science.gov (United States)

    Brown, S. J.; White, S.; Power, N.

    2015-01-01

    A cluster analysis data classification technique was used on assessment scores from 157 undergraduate nursing students who passed 2 successive compulsory courses in human anatomy and physiology. Student scores in five summative assessment tasks, taken in each of the courses, were used as inputs for a cluster analysis procedure. We aimed to group…

  7. Tracking Undergraduate Student Achievement in a First-Year Physiology Course Using a Cluster Analysis Approach

    Science.gov (United States)

    Brown, S. J.; White, S.; Power, N.

    2015-01-01

    A cluster analysis data classification technique was used on assessment scores from 157 undergraduate nursing students who passed 2 successive compulsory courses in human anatomy and physiology. Student scores in five summative assessment tasks, taken in each of the courses, were used as inputs for a cluster analysis procedure. We aimed to group…

  8. The Relationship between Human Operators' Psycho-physiological Condition and Human Errors in Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Arryum; Jang, Inseok; Kang, Hyungook; Seong, Poonghyun [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2013-05-15

    The safe operation of nuclear power plants (NPPs) is substantially dependent on the performance of the human operators who operate the systems. In this environment, human errors caused by inappropriate performance of operator have been considered to be critical since it may lead serious problems in the safety-critical plants. In order to provide meaningful insights to prevent human errors and enhance the human performance, operators' physiological conditions such as stress and workload have been investigated. Physiological measurements were considered as reliable tools to assess the stress and workload. T. Q. Tran et al. and J. B. Brooking et al pointed out that operators' workload can be assessed using eye tracking, galvanic skin response, electroencephalograms (EEGs), heart rate, respiration and other measurements. The purpose of this study is to investigate the effect of the human operators' tense level and knowledge level to the number of human errors. For this study, the experiments were conducted in the mimic of the main control rooms (MCR) in NPP. It utilized the compact nuclear simulator (CNS) which is modeled based on the three loop Pressurized Water Reactor, 993MWe, Kori unit 3 and 4 in Korea and the subjects were asked to follow the tasks described in the emergency operating procedures (EOP). During the simulation, three kinds of physiological measurement were utilized; Electrocardiogram (ECG), EEG and nose temperature. Also, subjects were divided into three groups based on their knowledge of the plant operation. The result shows that subjects who are tense make fewer errors. In addition, subjects who are in higher knowledge level tend to be tense and make fewer errors. For the ECG data, subjects who make fewer human errors tend to be located in higher tense level area of high SNS activity and low PSNS activity. The results of EEG data are also similar to ECG result. Beta power ratio of subjects who make fewer errors was higher. Since beta

  9. Techniques for Analysis of Plant Phenolic Compounds

    Directory of Open Access Journals (Sweden)

    Thomas H. Roberts

    2013-02-01

    Full Text Available Phenolic compounds are well-known phytochemicals found in all plants. They consist of simple phenols, benzoic and cinnamic acid, coumarins, tannins, lignins, lignans and flavonoids. Substantial developments in research focused on the extraction, identification and quantification of phenolic compounds as medicinal and/or dietary molecules have occurred over the last 25 years. Organic solvent extraction is the main method used to extract phenolics. Chemical procedures are used to detect the presence of total phenolics, while spectrophotometric and chromatographic techniques are utilized to identify and quantify individual phenolic compounds. This review addresses the application of different methodologies utilized in the analysis of phenolic compounds in plant-based products, including recent technical developments in the quantification of phenolics.

  10. Representation of the Physiological Factors Contributing to Postflight Changes in Functional Performance Using Motion Analysis Software

    Science.gov (United States)

    Parks, Kelsey

    2010-01-01

    Astronauts experience changes in multiple physiological systems due to exposure to the microgravity conditions of space flight. To understand how changes in physiological function influence functional performance, a testing procedure has been developed that evaluates both astronaut postflight functional performance and related physiological changes. Astronauts complete seven functional and physiological tests. The objective of this project is to use motion tracking and digitizing software to visually display the postflight decrement in the functional performance of the astronauts. The motion analysis software will be used to digitize astronaut data videos into stick figure videos to represent the astronauts as they perform the Functional Tasks Tests. This project will benefit NASA by allowing NASA scientists to present data of their neurological studies without revealing the identities of the astronauts.

  11. Weightlifter Lumbar Physiology Health Influence Factor Analysis of Sports Medicine.

    Science.gov (United States)

    Zhang, Xiangyang

    2015-01-01

    Chinese women's weightlifting project has been in the advanced world level, suggests that the Chinese coaches and athletes have many successful experience in the weight lifting training. Little weight lifting belongs to high-risk sports, however, to the lumbar spine injury, some young good athletes often due to lumbar trauma had to retire, and the national investment and athletes toil is regret things. This article from the perspective of sports medicine, weightlifting athletes training situation analysis and put forward Suggestions, aimed at avoiding lumbar injury, guarantee the health of athletes. In this paper, first of all to 50 professional women's weightlifting athletes doing investigation, found that 82% of the athletes suffer from lumbar disease symptoms, the reason is mainly composed of lumbar strain, intensity is too large, motion error caused by three factors. From the Angle of sports medicine and combined with the characteristics of the structure of human body skeleton athletes lumbar structural mechanics analysis, find out the lumbar force's two biggest technical movement, study, and regulate the action standard, so as to minimize lumbar force, for athletes to contribute to the health of the lumbar spine.

  12. A developmental biologist’s journey to rediscover the Zen of plant physiology [v1; ref status: indexed, http://f1000r.es/53n

    Directory of Open Access Journals (Sweden)

    José R. Dinneny

    2015-07-01

    Full Text Available Physiology, which is often viewed as a field of study distinct from development, is technically defined as the branch of biology that explores the normal function of living organisms and their parts. Because plants normally develop continuously throughout their life, plant physiology actually encompasses all developmental processes. Viewing plant biology from a physiologist’s perspective is an attempt to understand the interconnectedness of development, form, and function in the context of multidimensional complexity in the environment. To meet the needs of an expanding human population and a degrading environment, we must understand the adaptive mechanisms that plants use to acclimate to environmental change, and this will require a more holistic approach than is used by current molecular studies. Grand challenges for studies on plant physiology require a more sophisticated understanding of the environment that plants grow in, which is likely to be at least as complex as the plant itself. Moving the lab to the field and using the field for inspiration in the lab need to be expressly promoted by the community as we work to apply the basic concepts learned through reductionist approaches toward a more integrated and realistic understanding of the plant.

  13. Time series analysis of physiological response during ICU visitation.

    Science.gov (United States)

    Hepworth, J T; Hendrickson, S G; Lopez, J

    1994-12-01

    Time series analysis (TSA) is an important statistical procedure for clinical nursing research. The current paucity of nursing research reports using TSA may be due to unfamiliarity with this technique. In this article, TSA is compared with the ordinary least squares regression model; validity concerns of time series designs are discussed; and concomitant and interrupted TSA of data collected on the effects of family visitation on intracranial pressure (ICP), heart rate, and blood pressure of patients in ICUs are presented. The concomitant TSA of the effect of family on ICP suggested that family presence tended to be associated with decreased ICP. Interrupted TSA indicated the effect of family on heart rate and blood pressure was not as consistent: The overall effect on blood pressure appeared to be negligible, and heart rate may increase overall. Restrictive visiting policies, once typical of intensive care units, should be reconsidered.

  14. Predicting invasive species impacts on hydrological processes: the consequences of plant physiology for landscape processes

    CSIR Research Space (South Africa)

    Le Maitre, David C

    2004-01-01

    Full Text Available stream_source_info Le maitre _2004.pdf.txt stream_content_type text/plain stream_size 13237 Content-Encoding ISO-8859-1 stream_name Le maitre _2004.pdf.txt Content-Type text/plain; charset=ISO-8859-1 1408 Weed Technology... that reduce evaporation in practice to ??actual Et?? (Jarvis and McNaughton 1986). Most of these ap- WEED TECHNOLOGY Volume 18, Invasive Weed Symposium 2004 1409 Figure 1. Root depth distributions for plants with different growth forms based on data compiled...

  15. Plant physiology at the institute for philosophy in Brno in Mendel’s teacher F. Diebl textbook from 1835

    Directory of Open Access Journals (Sweden)

    Jiří Šebánek

    2012-01-01

    Full Text Available Gregor Mendel attended lectures of F. Diebl, professor of natural history and agricultural science at the Institute of Philosophy in Brno. Diebl published his lectures in a textbook “Abhandlungen über die allgemeine und besondere Naturgeschichte, Brünn 1835.” From the textbook the level of scientific knowledge in plant biology is obvious, with which the later founder of a new field of biology – genetics got acquainted. Diebl considered germination to be a specific method of fermentation transforming seed starch into a sugary matter which nourishes the germinating plant. In the physiology of nutrition he distinguished nutrition from the soil via roots from nutrition from the air via leaves. The former is based primarily on the humus theory of A. Thaer (1809 because not until 5 years after the publication of Diebl’s textbook J. Liebig initiated the mineral theory. Diebl’s presentation of photosynthesis was based on information available at that time about the release of oxygen by green plants under conditions of light and the uptake of CO2, but he had no knowledge about the passage of CO2 into the leaves through stomata. Remarkable is Diebl’s discovery that respiration increases during flowering. Electricity is considered to be a force significantly supporting the life processes of plants. Diebl also noticed the difference between diurnal and night evaporation of water from the leaves. In his textbook growth is connected with nutrition only, as it was the entire 19th century. Stem thickening from the cambium is described very simply. Bud and root regeneration is given the term reproduction which today is commonly used in relation to sexual reproduction. Diebl considered nyctinastic movements (bending or unbending of the leaves and closing of the flowers at night to be “sleep”. He described fertilisation in a primitive way, because it was not until 1848 that the first exact description came out.

  16. Physiological and genetic control mechanisms for plant adaptation to high temperature and elevated CO2

    Energy Technology Data Exchange (ETDEWEB)

    Zeiger, Eduardo

    2001-02-01

    Acclimations of the stomatal response to CO2 were characterized. Stomata from the model plant used, Vicia faba, are very sensitive to ambient CO2 when grown in growth chambers as compared to stomata from green house grown leaves. The different CO2 sensitivities of growth chamber and green house grown guard cells was confirmed by reciprocal transfer experiments. Stomata acclimated to their new environment and acquired the CO2 sensitivity typical of that environment. A mechanism for CO2 sensing was also characterized. Results show that CO2 concentration alters the concentration of zeaxanthin in the guard cell chloroplast, thus modifying the light response of the guard cells. This mechanism accounts for the well characterized interactions of light and CO2 in the stomatal responses. The xanthophyll cycle in the stomata of the facultative CAM plant, Mesembryanthemum crystallinum, was characterized. In the C3 mode, zeaxanthin is formed in the light and stomata open. Upon induction of the CAM mode, zeaxanthin synthesis is blocked and stomata no longer respond to light. These results implicate the regulation of the xanthophyll cycle of guard cells in the CAM adaptation.

  17. PHYSIOLOGICAL RESPONSE AND YIELD OF PEPPER PLANTS (CAPSICUM ANNUM L. TO ORGANIC FERTILIZATION

    Directory of Open Access Journals (Sweden)

    Małgorzata BEROVA

    2009-06-01

    Full Text Available The experience was brought out to the experimental fi eld of the Agroecological Centre at the Agricultural University of Plovdiv which owns a Certifi cate of ecological farm work. The research was carried out on two pepper cultivars: Gorogled 6 and Buketen 50 – intended for production of red pepper for grinding. For the purpose of the experiment a bio-fertilizer, produced by the Californian earthworm Lumbricus rubellus was used. Two levels of the bio-fertilizer were applied - 50 and 100 ml/per plant. It was determined that the bio-fertilizer speeds up plant growth. It infl uences the growth rate of the roots and stems and affects the formation of the foliage. The bio-fertilizer has a positive effect upon the functional activity of the photosynthetic apparatus /increased content of photosynthetic pigments, improved leaf gas exchange/. The biofertilizer also infl uences the yield (raw material for drying. The highest effect has been achieved at application of 100 ml fertilizer to the Gorogled 6 cultivar.

  18. Effect of aluminium uptake on physiology, phenols and amino acids in Matricaria chamomilla plants.

    Science.gov (United States)

    Kovácik, Jozef; Klejdus, Borivoj; Hedbavny, Josef

    2010-06-15

    Chamomile is a widely used medicinal plant and, as observed in our previous studies, also accumulates some metals in its above-ground biomass. We therefore tested selected metabolic responses after treatments with 60 and 120 microM Al for 7 days. Shoot Al content was not elevated in comparison with control (12.3-14.1 microg g(-1) DW) while total root Al increased strongly, reaching 2680 and 4400 microg g(-1) DW in 60 and 120 microM treatments, respectively. "Intra-root" Al represented 83.6 (60 microM treatment) and 75.8% (120 microM treatment) of total root Al. Soluble proteins were not significantly affected. Free amino acids were almost unaffected in shoots while in roots the highest content was found in 60 microM Al. Ascorbate- and guaiacol-peroxidase activities were the highest in 60 microM Al-exposed roots. On the other hand, phenylalanine ammonia-lyase activity, total soluble phenols, flavonoids, a sum of 13 phenolic acids and partially two flavonols (quercetin and kaempferol) increased in the shoots. Present study has shown lower Al toxicity and unaltered shoot Al content seems to be the most positive outcome in comparison with previously tested metals (Cd, Ni and Cu). Our results indicate that phenols in shoots and free amino acids in roots are influenced by Al excess in chamomile plants. Possible mechanisms in the context of available literature are suggested and discussed.

  19. The assessment of physiology parameters of willow plants as a criterion for selection of prospective clones

    Directory of Open Access Journals (Sweden)

    Rodzkin Aleh I.

    2015-01-01

    Full Text Available Bioenergy production based on short rotation coppice willow plantations (SRC is an effective direction both for economic and environment profit. The yield of willow wood can amount to 10-15 tons per hectare of dry biomass per year and the cost of thus obtained energy is lower in comparison with other energy crops. In order to achieve high yield and profitability, the use of special willow clones is necessary. Species most often used in selection for biomass production are shrub type willows: Salix viminalis, Salix dasyclados and Salix schwerini, while the clones tested in this paper were also of tree species Salix alba. The productivity and some physiology characteristics of Serbian selection clones of Salix alba (Bačka, Volmianka and Drina and Swedish selection clone Jorr (Salix viminalis were investigated in greenhouses and in field conditions. As the result of testing three clones of Salix alba - Bačka, Volmianka and Drina, having special preferences and adaptability to different environmental conditions, these were included in State register of Republic of Belarus in 2013. In our experiment it was also satisfactory that specific properties of willows (intensity of transpiration and photosynthesis, water use efficiency and others, were conserved both in greenhouses and in field conditions. This factor gives opportunity to select prospective clones of willows at an early stage of ontogenesis for further testing.

  20. Effects of salinity on anatomical features and physiology of a semi-mangrove plant Myoporum bontioides.

    Science.gov (United States)

    Xu, H M; Tam, N F Y; Zan, Q J; Bai, M; Shin, P K S; Vrijmoed, L L P; Cheung, S G; Liao, W B

    2014-08-30

    The effect of different concentrations of NaCl, 0, 100, 200, 300 and 400 mM, on the anatomical features and physiology of Myoporum bontioides was investigated. The photosynthetic rates (Pn) were significantly reduced by salt stress, with the lowest values at 400 mM NaCl. The content of malondialdehyde (MDA), proline and soluble sugar, as well as the activities of peroxidase (POD) and catalase (CAT) increased at the beginning, but became similar to the control as the experiment proceeded. The NaCl effect on superoxide dismutase (SOD) was different from the other parameters, with a significant reduction at 400 mM NaCl at Day 7. Salt glands were found in both upper and lower epidermis, and the ratios of the thickness of palisade to spongy mesophyll tissues increased with NaCl concentrations. The medullary ray was clearly damaged by NaCl at levels of 200 and 300 mM. These results demonstrated that M. bontioides could adapt to a relatively low salinity, and was not a halophilous species.

  1. Physiological responses of root-less epiphytic plants to acid rain.

    Science.gov (United States)

    Kováčik, Jozef; Klejdus, Bořivoj; Bačkor, Martin; Stork, František; Hedbavny, Josef

    2011-03-01

    Selected physiological responses of Tillandsia albida (Bromeliaceae) and two lichens (Hypogymnia physodes and Xanthoria parietina) exposed to simulated acid rain (AR) over 3 months were studied. Pigments were depressed in all species being affected the most in Tillandsia. Amounts of hydrogen peroxide and superoxide were elevated and soluble proteins decreased only in AR-exposed Hypogymnia. Free amino acids were slightly affected among species and only glutamate sharply decreased in AR-exposed Xanthoria. Slight increase in soluble phenols but decrease in flavonoids in almost all species suggests that the latter are not essential for tolerance to AR. Almost all phenolic acids in Tillandsia leaves decreased in response to AR and activities of selected enzymes (phenylalanine ammonia-lyase, polyphenol oxidase, ascorbate- and guaiacol-peroxidase) were enhanced by AR. In lichens, considerable increase in metabolites (physodalic acid, atranorin and parietin) in response to AR was found but amount of ergosterol was unchanged. Macronutrients (K, Ca, Mg) decreased more pronouncedly in comparison with micronutrients in all species. Xanthoria showed higher tolerance in comparison with Hypogymnia, suggesting that could be useful for long-term biomonitoring.

  2. Quantitative aerobic physiology of the yeast Dekkera bruxellensis, a major contaminant in bioethanol production plants.

    Science.gov (United States)

    Leite, Fernanda Cristina Bezerra; Basso, Thiago Olitta; Pita, Will de Barros; Gombert, Andreas Karoly; Simões, Diogo Ardaillon; de Morais, Marcos Antonio

    2013-02-01

    Dekkera bruxellensis has been described as the major contaminant yeast of industrial ethanol production, although little is known about its physiology. The aim of this study was to investigate the growth of this yeast in diverse carbon sources and involved conducting shake-flask and glucose- or sucrose-limited chemostats experiments, and from the chemostat data, the stoichiometry of biomass formation during aerobic growth was established. As a result of the shake-flask experiments with hexoses or disaccharides, the specific growth rates were calculated, and a different behavior in rich and mineral medium was observed concerning to profile of acetate and ethanol production. In C-limited chemostats conditions, the metabolism of this yeast was completely respiratory, and the biomass yields reached values of 0.62 gDW gS(-1) . In addition, glucose pulses were applied to the glucose- or sucrose-limited chemostats. These results showed that D. bruxellensis has a short-term Crabtree effect. While the glucose pulse was at the sucrose-limited chemostat, sucrose accumulated at the reactor, indicating the presence of a glucose repression mechanism in D. bruxellensis. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  3. Protection of palak (Beta vulgaris L. var Allgreen) plants from ozone injury by ethylenediurea (EDU): roles of biochemical and physiological variations in alleviating the adverse impacts.

    Science.gov (United States)

    Tiwari, Supriya; Agrawal, Madhoolika

    2009-06-01

    Ameliorative effects of ethylenediurea (N-[2-(2-oxo-1-imidazolinidyl) ethyl]-N' phenylurea, abbreviated as EDU) against ozone stress were studied on selected growth, biochemical, physiological and yield characteristics of palak (Beta vulgaris L. var Allgreen) plants grown in field at a suburban site of Varanasi, India. Mean eight hourly ozone concentration varied from 52 to 73 ppb which was found to produce adverse impacts on plant functioning and growth characteristics. The palak plants were treated with 300 ppm EDU at 10 days after germination at 10 days interval up to the plant maturity. Lipid peroxidation in EDU treated plants declined significantly as compared to non-EDU treated ones. Significant increment in F(v)/F(m) ratio in EDU treated plants as compared to non-EDU treated ones was recorded. EDU treated plants showed significant increment in ascorbic acid contents and reduction in peroxidase activity as compared to non-EDU treated ones. As a result of the protection provided by EDU against ozone induced stress on biochemical and physiological characteristics of palak, the morphological parameters also responded positively. Significant increments were recorded in shoot length, number of leaves plant(-1), leaf area and root and shoot biomass of EDU treated plants as compared to non-EDU treated ones. Contents of Na, K, Ca, Mg and Fe were higher in EDU treated plants as compared to non-EDU treated ones. The present investigation proves the usefulness of EDU in partially ameliorating ozone injury in ambient conditions.

  4. Advanced Power Plant Development and Analysis Methodologies

    Energy Technology Data Exchange (ETDEWEB)

    A.D. Rao; G.S. Samuelsen; F.L. Robson; B. Washom; S.G. Berenyi

    2006-06-30

    Under the sponsorship of the U.S. Department of Energy/National Energy Technology Laboratory, a multi-disciplinary team led by the Advanced Power and Energy Program of the University of California at Irvine is defining the system engineering issues associated with the integration of key components and subsystems into advanced power plant systems with goals of achieving high efficiency and minimized environmental impact while using fossil fuels. These power plant concepts include 'Zero Emission' power plants and the 'FutureGen' H2 co-production facilities. The study is broken down into three phases. Phase 1 of this study consisted of utilizing advanced technologies that are expected to be available in the 'Vision 21' time frame such as mega scale fuel cell based hybrids. Phase 2 includes current state-of-the-art technologies and those expected to be deployed in the nearer term such as advanced gas turbines and high temperature membranes for separating gas species and advanced gasifier concepts. Phase 3 includes identification of gas turbine based cycles and engine configurations suitable to coal-based gasification applications and the conceptualization of the balance of plant technology, heat integration, and the bottoming cycle for analysis in a future study. Also included in Phase 3 is the task of acquiring/providing turbo-machinery in order to gather turbo-charger performance data that may be used to verify simulation models as well as establishing system design constraints. The results of these various investigations will serve as a guide for the U. S. Department of Energy in identifying the research areas and technologies that warrant further support.

  5. Temperate heath plant response to dry conditions depends on growth strategy and less on physiology

    DEFF Research Database (Denmark)

    Albert, Kristian Rost; Kongstad, J.; Schmidt, I. K.

    2012-01-01

    The evidence that is currently available demonstrates that future changes in precipitation patterns will affect plant carbon uptake. However, the outcome in terms of success, productivity and fecundity depends upon individual species and different responses of various growth forms. Examination...... of these differences in response in dry versus rewetting conditions can be used to highlight the limitations coherent in different strategies adopted by, for example, evergreen shrubs and grasses. We investigated the leaf-level photosynthetic performance, leaf C, N and d13C along with vegetation cover and biomass...... rewetting increased leaf nitrogen and photosynthesis in the grass much more than for the dwarf shrub. These different strategies may have a considerable impact on carbon uptake and on the ability of a species to compete, as future climatic changes are likely to extend the summer drought period together...

  6. Physiological Functions of Cyclic Electron Transport Around Photosystem I in Sustaining Photosynthesis and Plant Growth.

    Science.gov (United States)

    Yamori, Wataru; Shikanai, Toshiharu

    2016-04-29

    The light reactions in photosynthesis drive both linear and cyclic electron transport around photosystem I (PSI). Linear electron transport generates both ATP and NADPH, whereas PSI cyclic electron transport produces ATP without producing NADPH. PSI cyclic electron transport is thought to be essential for balancing the ATP/NADPH production ratio and for protecting both photosystems from damage caused by stromal overreduction. Two distinct pathways of cyclic electron transport have been proposed in angiosperms: a major pathway that depends on the PROTON GRADIENT REGULATION 5 (PGR5) and PGR5-LIKE PHOTOSYNTHETIC PHENOTYPE 1 (PGRL1) proteins, which are the target site of antimycin A, and a minor pathway mediated by the chloroplast NADH dehydrogenase-like (NDH) complex. Recently, the regulation of PSI cyclic electron transport has been recognized as essential for photosynthesis and plant growth. In this review, we summarize the possible functions and importance of the two pathways of PSI cyclic electron transport.

  7. Determinants of parasitoid communities of willow-galling sawflies: habitat overrides physiology, host plant and space.

    Science.gov (United States)

    Nyman, Tommi; Leppänen, Sanna A; Várkonyi, Gergely; Shaw, Mark R; Koivisto, Reijo; Barstad, Trond Elling; Vikberg, Veli; Roininen, Heikki

    2015-10-01

    Studies on the determinants of plant-herbivore and herbivore-parasitoid associations provide important insights into the origin and maintenance of global and local species richness. If parasitoids are specialists on herbivore niches rather than on herbivore taxa, then alternating escape of herbivores into novel niches and delayed resource tracking by parasitoids could fuel diversification at both trophic levels. We used DNA barcoding to identify parasitoids that attack larvae of seven Pontania sawfly species that induce leaf galls on eight willow species growing in subarctic and arctic-alpine habitats in three geographic locations in northern Fennoscandia, and then applied distance- and model-based multivariate analyses and phylogenetic regression methods to evaluate the hierarchical importance of location, phylogeny and different galler niche dimensions on parasitoid host use. We found statistically significant variation in parasitoid communities across geographic locations and willow host species, but the differences were mainly quantitative due to extensive sharing of enemies among gallers within habitat types. By contrast, the divide between habitats defined two qualitatively different network compartments, because many common parasitoids exhibited strong habitat preference. Galler and parasitoid phylogenies did not explain associations, because distantly related arctic-alpine gallers were attacked by a species-poor enemy community dominated by two parasitoid species that most likely have independently tracked the gallers' evolutionary shifts into the novel habitat. Our results indicate that barcode- and phylogeny-based analyses of food webs that span forested vs. tundra or grassland environments could improve our understanding of vertical diversification effects in complex plant-herbivore-parasitoid networks. © 2015 John Wiley & Sons Ltd.

  8. Morphological, physiological and biochemical responses of biofuel plant Euphorbia lathyris to salt stress

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jie; Cao, Yan; Yang, Ziyi; Lu, Changmei [Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Science, Nanjing Normal Univ., Nanjing (China)], E-mail: 08134@njnu.edu.cn); Zhang, Weiming; Sun, Lijun [Nanjing Inst. for the Comprehensive Utilization of Wild plants, Nanjing (China)

    2013-05-15

    Saline lands are characterized by salinity and nutrient deficiency and there is an ever increasing need for economical, adaptable plant species to rejuvenate these lands. In this study, we determined the suitability and tolerance of Euphorbia lathyris L. (Caper spurge), a well-known biofuel plant, as a sustainable candidate to colonize saline lands. We investigated the germination rate, seedling growth, solute change and anti-oxidative enzyme activities etc. under salt stress conditions. Our results showed that Caper spurge seeds prefer to germinate under nonsaline environments and high salt stress induced temporary dormancy during germination, but did not completely hamper the viability of the seeds. The seedling biomass increased without any visible distress symptoms in the presence of NaCl not over 171 mM. Further increase in NaCl concentration had a negative impact on the seedling growth. These demonstrate that Caper spurge seedlings have the potential to grow in saline lands. The salinity tolerance of Caper spurge seedlings was closely associated with the regional distribution of Na{sup + }in roots, stable absorption of Ca{sup 2{sup +,}} K{sup + }and Mg{sup 2{sup +,}} accumulation of organic solutes, and increased activity of superoxide dismutase (SOD) and catalase (CAT) enzymes. However, excessive accumulation of Na{sup +,} sharp increase of superoxide (O{sub 2}), H{sub 2}O{sub 2}, malonaldehyde (MDA) and cell membrane leakage, reduction of osmoprotectants, and decreased activities of CAT and ascorbate peroxidase (APX) etc. under high salinity might be the reasons for the restrained seedling growth.

  9. Match analysis and the physiological demands of Australian football.

    Science.gov (United States)

    Gray, Adrian J; Jenkins, David G

    2010-04-01

    Australian Football, the most popular football code in Australia, is a contact sport played by two teams of 18 players who contest play over four 20-minute quarters; the object of the game is to score the most points through goal kicking. Sixteen professional senior sides compete against each other in the Australian Football League (AFL) and, similar to other football codes, game demands at the elite level in the AFL have changed considerably in recent years. Early time-motion analysis studies highlighted the long periods of time players spent in low intensity activities (standing and walking). While recent studies utilizing global positioning systems (GPS) technology are somewhat in agreement with earlier findings, available evidence suggests that the game is getting faster. For example, 'playing on' after a mark (a feature of the game where players who catch the ball on the full from a kick longer than 15 m are awarded a free kick) is now much quicker. Indeed, rule changes in recent years have increased the flow and speed of the game; there has been a reduction in the time taken for umpires to restart play, and for players to kick-in (after the opposition kicks a behind) or take a set shot at goal. Nomadic players (a broad term for midfielders and ruckmen because they follow play over the entire playing field) cover slightly greater distances (12,310 m) than both forwards (11,920 m) and backs (11,880 m) in a game. Compared with players in other positions, midfielders are consistently found to spend the most time at higher intensities (running and sprint efforts with movement velocities > 4.44 m/sec), complete more high intensity efforts (approximately 98 per game), sustain them for longer and have shorter recovery periods between high intensity exercise bouts (approximately 90 seconds on average). 'Ruckmen' have similar but less intense running profiles, while forwards and backs generally have less game involvement but have a more intermittent running profile

  10. Application of Spectral Reflectance on Research of Plant Eco-Physiology%光谱分析在植物生理生态研究中的应用

    Institute of Scientific and Technical Information of China (English)

    薛忠财; 高辉远; 彭涛; 姚广

    2011-01-01

    本文介绍了光谱分析技术在植物生理生态研究中的应用.通过分析植物叶片和冠层的反射光谱特征,可以快速、无损伤地研究不同环境条件下植物的各种色素含量,叶黄素循环组分、营养状况、水分状况、光能利用效率、植被盖度以及冠层结构等生理生态特征,此外光谱分析还能用来监测湖泊、河流中水华的发生和分布,研究生态系统中CO2和H2O的通量以及各种逆境胁迫和放牧等对植物生长的影响.%The application of spectral reflectance on research of plant eco-physiology was reviewed. By analysis of spectral reflectance of plant on leaf or canopy levels, concentration of different kinds of pigments,components of xanthophyll cycle, nutrition status, water status, light use efficiency, vegetation coverage and canopy structure of plant under different environments can be fast and non-destructively investigated. In addition, the spectral reflectance can be used to detect algae-bloom in lakes and rivers, carbon and water vapor fluxes in ecosystem atmosphere, and effect of different kinds of stress and graze on plant growth.

  11. An integrative approach to space-flight physiology using systems analysis and mathematical simulation

    Science.gov (United States)

    Leonard, J. I.; White, R. J.; Rummel, J. A.

    1980-01-01

    An approach was developed to aid in the integration of many of the biomedical findings of space flight, using systems analysis. The mathematical tools used in accomplishing this task include an automated data base, a biostatistical and data analysis system, and a wide variety of mathematical simulation models of physiological systems. A keystone of this effort was the evaluation of physiological hypotheses using the simulation models and the prediction of the consequences of these hypotheses on many physiological quantities, some of which were not amenable to direct measurement. This approach led to improvements in the model, refinements of the hypotheses, a tentative integrated hypothesis for adaptation to weightlessness, and specific recommendations for new flight experiments.

  12. Physiological and biochemical effect of neem and other Meliaceae plants secondary metabolites against Lepidopteran insects

    Directory of Open Access Journals (Sweden)

    Senthil-Nathan eSengottayan

    2013-12-01

    Full Text Available This review described the physiological and biochemical effects of various secondary metabolites from Meliaceae against major Lepidopteran insect pest including, Noctuidae and Pyralidae. The biochemical effect of major Meliaceae secondary metabolites were discussed more in this review. Several enzymes based on food materials have critical roles in nutritional indices (food utilization of the insect pest population. Several research work has been referred and the effect of Meliaceae secondary metabolites on feeding parameters of insects by demonstrating food consumption, approximate digestibility of consumed food, efficiency of converting the ingested food to body substance, efficiency of converting digested food to body substance and consumption index was reviewed in detail. Further how the digestive enzymes including a-Amylases, α and β- glucosidases (EC 3.2.1.1, lipases (EC 3.1.1 Proteases, serine, cysteine, and aspartic proteinases affected by the Meliaceae secondary metabolites was reviewed. Further effect of Meliaceae secondary metabolites on detoxifying enzymes have been found to react against botanical insecticides including general esterases (EST, glutathione S-transferase (GST and phosphatases was reviewed. Alkaline phosphatase (ALP, E.C.3.1.3.1 and acid phosphatase (ACP, E.C.3.1.3.2 are hydrolytic enzymes, which hydrolyze phosphomonoesters under alkaline or acid conditions, respectively. These enzymes were affected by the secondary metabolites treatment. The detailed mechanism of action was further explained in this review. Acethylcholine esterase (AChE is a key enzyme that terminates nerve impulses by catalyzing the hydrolysis of neurotransmitter, acetylcholine, in the nervous system of various organisms. How the AChE activity was altered by the Meliaceae secondary metabolites reviewed in detail.

  13. Potential of the Sentinel-2 Red Edge Spectral Bands for Estimation of Eco-Physiological Plant Parameters

    Science.gov (United States)

    Malenovsky, Zbynek; Homolova, Lucie; Janoutova, Ruzena; Landier, Lucas; Gastellu-Etchegorry, Jean-Philippe; Berthelot, Beatrice; Huck, Alexis

    2016-08-01

    In this study we investigated importance of the space- borne instrument Sentinel-2 red edge spectral bands and reconstructed red edge position (REP) for retrieval of the three eco-physiological plant parameters, leaf and canopy chlorophyll content and leaf area index (LAI), in case of maize agricultural fields and beech and spruce forest stands. Sentinel-2 spectral bands and REP of the investigated vegetation canopies were simulated in the Discrete Anisotropic Radiative Transfer (DART) model. Their potential for estimation of the plant parameters was assessed through training support vector regressions (SVR) and examining their P-vector matrices indicating significance of each input. The trained SVR were then applied on Sentinel-2 simulated images and the acquired estimates were cross-compared with results from high spatial resolution airborne retrievals. Results showed that contribution of REP was significant for canopy chlorophyll content, but less significant for leaf chlorophyll content and insignificant for leaf area index estimations. However, the red edge spectral bands contributed strongly to the retrievals of all parameters, especially canopy and leaf chlorophyll content. Application of SVR on Sentinel-2 simulated images demonstrated, in general, an overestimation of leaf chlorophyll content and an underestimation of LAI when compared to the reciprocal airborne estimates. In the follow-up investigation, we will apply the trained SVR algorithms on real Sentinel-2 multispectral images acquired during vegetation seasons 2015 and 2016.

  14. [Effects of soil moisture content and light intensity on the plant growth and leaf physiological characteristics of squash].

    Science.gov (United States)

    Du, She-ni; Bai, Gang-shuan; Liang, Yin-li

    2011-04-01

    A pot experiment with artificial shading was conducted to study the effects of soil moisture content and light intensity on the plant growth and leaf physiological characteristics of squash variety "Jingyingyihao". Under all test soil moisture conditions, 30% shading promoted the growth of "Jingyingyihao", with the highest yield at 70% - 80% soil relative moisture contents. 70% shading inhibited plant growth severely, only flowering and not bearing fruits, no economic yield produced. In all treatments, there was a similar water consumption trend, i. e., both the daily and the total water consumption decreased with increasing shading and decreasing soil moisture content. Among all treatments, 30% shading and 70% - 80% soil relative moisture contents had the highest water use efficiency (2.36 kg mm(-1) hm(-2)) and water output rate (1.57 kg mm(-1) hm(-2)). The net photosynthetic rate, transpiration rate, stomatal conductance, and chlorophyll content of squash leaves decreased with increasing shading, whereas the intercellular CO2 concentration was in adverse. The leaf protective enzyme activity and proline content decreased with increasing shading, and the leaf MAD content decreased in the order of 70% shading, natural radiation, and 30% shading. Under the three light intensities, the change characteristics of squash leaf photosynthesis, protective enzyme activity, and proline and MAD contents differed with the increase of soil relative moisture content.

  15. MORPHOPHYSIOLOGICAL ANALYSIS OF PASSION FRUIT PLANTS FROM DIFFERENT PROPAGATION METHODS AND PLANTING SPACING

    Directory of Open Access Journals (Sweden)

    JERFFSON LUCAS SANTOS

    2016-01-01

    Full Text Available The passion fruit (Passiflora cincinnata Mast. is a perennial and drought resistant species that represents a new alternative crop for small farmers in rainfed conditions. This study aimed to evaluate the vegetative and physiological development of passion fruit plants derived from two propagation methods and grown at varied planting spacing. The experiment was conducted from January to June of 2012, in the Universidade Estadual do Sudoeste da Bahia (State University from Southwestern Bahia, in Brazil. It was carried out in a randomized block design under a 2 x 3 factorial scheme, which consisted of two propagation methods (cutting and seeds and three planting spacing distances within a row (1.5; 3.0 and 4.0 m, however, at same distance between rows (3.0 m, with four replicates and four plants per plot. Cuttings and seeds were sampled from adult plants pre-selected in native areas from Vitória da Conquista - BA, Brazil. Growth (stem diameter and leaf area and physiological parameters (leaf chlorophyll content, leaf water potential before dawn, relative water content and leaf gas exchange were assessed on the 90th, 120th and 150th day after transplanting of seedlings into the field (DAT. Based on our results, we concluded that despite plants propagated via cuttings showed most favorable water status, vegetative growth and photosynthetic capacity were lower whether compared to plants obtained from seeds.

  16. Physiological Investigation and Transcriptome Analysis of Polyethylene Glycol (PEG)-Induced Dehydration Stress in Cassava.

    Science.gov (United States)

    Fu, Lili; Ding, Zehong; Han, Bingying; Hu, Wei; Li, Yajun; Zhang, Jiaming

    2016-01-01

    Cassava is an important tropical and sub-tropical root crop that is adapted to drought environment. However, severe drought stress significantly influences biomass accumulation and starchy root production. The mechanism underlying drought-tolerance remains obscure in cassava. In this study, changes of physiological characters and gene transcriptome profiles were investigated under dehydration stress simulated by polyethylene glycol (PEG) treatments. Five traits, including peroxidase (POD) activity, proline content, malondialdehyde (MDA), soluble sugar and soluble protein, were all dramatically induced in response to PEG treatment. RNA-seq analysis revealed a gradient decrease of differentially expressed (DE) gene number in tissues from bottom to top of a plant, suggesting that cassava root has a quicker response and more induced/depressed DE genes than leaves in response to drought. Overall, dynamic changes of gene expression profiles in cassava root and leaves were uncovered: genes related to glycolysis, abscisic acid and ethylene biosynthesis, lipid metabolism, protein degradation, and second metabolism of flavonoids were significantly induced, while genes associated with cell cycle/organization, cell wall synthesis and degradation, DNA synthesis and chromatin structure, protein synthesis, light reaction of photosynthesis, gibberelin pathways and abiotic stress were greatly depressed. Finally, novel pathways in ABA-dependent and ABA-independent regulatory networks underlying PEG-induced dehydration response in cassava were detected, and the RNA-Seq results of a subset of fifteen genes were confirmed by real-time PCR. The findings will improve our understanding of the mechanism related to dehydration stress-tolerance in cassava and will provide useful candidate genes for breeding of cassava varieties better adapted to drought environment.

  17. Physiological Investigation and Transcriptome Analysis of Polyethylene Glycol (PEG-Induced Dehydration Stress in Cassava

    Directory of Open Access Journals (Sweden)

    Lili Fu

    2016-02-01

    Full Text Available Cassava is an important tropical and sub-tropical root crop that is adapted to drought environment. However, severe drought stress significantly influences biomass accumulation and starchy root production. The mechanism underlying drought-tolerance remains obscure in cassava. In this study, changes of physiological characters and gene transcriptome profiles were investigated under dehydration stress simulated by polyethylene glycol (PEG treatments. Five traits, including peroxidase (POD activity, proline content, malondialdehyde (MDA, soluble sugar and soluble protein, were all dramatically induced in response to PEG treatment. RNA-seq analysis revealed a gradient decrease of differentially expressed (DE gene number in tissues from bottom to top of a plant, suggesting that cassava root has a quicker response and more induced/depressed DE genes than leaves in response to drought. Overall, dynamic changes of gene expression profiles in cassava root and leaves were uncovered: genes related to glycolysis, abscisic acid and ethylene biosynthesis, lipid metabolism, protein degradation, and second metabolism of flavonoids were significantly induced, while genes associated with cell cycle/organization, cell wall synthesis and degradation, DNA synthesis and chromatin structure, protein synthesis, light reaction of photosynthesis, gibberelin pathways and abiotic stress were greatly depressed. Finally, novel pathways in ABA-dependent and ABA-independent regulatory networks underlying PEG-induced dehydration response in cassava were detected, and the RNA-Seq results of a subset of fifteen genes were confirmed by real-time PCR. The findings will improve our understanding of the mechanism related to dehydration stress-tolerance in cassava and will provide useful candidate genes for breeding of cassava varieties better adapted to drought environment.

  18. Effects of cerium on growth and physiological mechanism in plants under enhanced ultraviolet-B radiation

    Institute of Scientific and Technical Information of China (English)

    LIANG Chan-juan; HUANG Xiao-hua; TAO Wen-yi; ZHOU Qing

    2006-01-01

    Effect of cerium (Ce3+) on the growth, photosynthesis and antioxidant enzyme system in rape seedlings (Brassica juncea L.)exposed to two levels of UV-B radiation (T1: 0.15 W/m2 and T2:0.35 W/m2) was studied by hydroponics under laboratory conditions.After 5 d of UV-B treatment, the aboveground growth indices were obviously decreased by 13.2%-44.1%(T1) and 21.4%-49.3%(T2), compared to CK, and except active absorption area of roots, the belowground indices by 14.1%-35.6%(T1) and 20.3%-42.6%(T2). For Ce+UV-B treatments, the aboveground and belowground growth indices were decreased respectively by 4.1%-23.6%, 5.2%-23.3%(Ce+T1) and 10.8%-28.4%, 7.0%-27.8%(Ce+T2), lower than those of UV-B treatments. The decrease of growth indices appeared to be the result of changes of physiological processes. Two levels of UV-B radiation induced the decrease in chlorophyll content, net photosynthesis rate, transpiration rate, stomatal conductance and water use efficiency by 11.2%-25.9%(T1) and 20.9%-56.9%(T2), whereas increase in membrane permeability and activities of antioxidant enzymes including superoxide dismutase(SOD),catalase (CAT) and peroxidase (POD) by 6.9%, 22.8%, 21.5%, 9.5%(T1) and 36.6%, 122.3%, 103.5%, 208.9%(T2), respectively. The reduction of the photosynthetic parameters in Ce+UV-B treatments was lessened to 3.2%-13.8%(Ce+T1) and 4.9%-27.6%(Ce+T2),and the increase of membrane permeability and activities of antioxidant enzymes except POD in the same treatments were lessened to 2.4%, 8.4%, 6.6%(Ce+T1) and 30.1%, 116.7%, 75.4%(Ce+T2). These results indicate that the regulative effect of Ce on photosynthesis and antioxidant enzymatic function is the ecophysiological basis of alleviating the suppression of UV-B radiation on growth of seedlings. Furthermore, the protective effect of Ce on seedlings exposed to T1 level of UV-B radiation is superior to T2 level.

  19. Effect of soil salinity on physiological characteristics of functional leaves of cotton plants.

    Science.gov (United States)

    Zhang, Lei; Zhang, Guowei; Wang, Youhua; Zhou, Zhiguo; Meng, Yali; Chen, Binglin

    2013-03-01

    This study analyzes the effects of soil salinity on fatty acid composition, antioxidative enzyme activity, lipid peroxidation, and photosynthesis in functional leaves during the flowering and boll-forming stages of two cotton cultivars, namely, CCRI-44 (salt-tolerant) and Sumian 12 (salt-sensitive), grown under different soil salinity conditions. Saturated (C16:0 and C18:0) and unsaturated fatty acid (FA) contents (C18:1), as well as superoxide dismutase activity increased, whereas high-unsaturated FA (C18:2 and C18:3) decreased, with the increase in soil salinity. The production of malondialdehyde increased with increasing lipoxygenase (LOX) activity, indicating that LOX catalyzed FA peroxidation under salt stress. Soil salinity had no significant effect on catalase (CAT) and peroxidases (POD) activity in the salt-sensitive cultivar Sumian 12, but significantly increased CAT and POD activities in the salt-tolerant cultivar CCRI-44. Net photosynthesis and stomatal conductance of the cotton cultivars decreased in response to salt stress; however, CCRI-44 showed a smaller reduction in photosynthesis than Sumian 12. The results indicated that stomatal apparatus limited leaf photosynthetic capacity in the salinity-treated plants of both cultivars. The net photosynthetic rate, maximum photochemical efficiency, and photochemical quantum yield of the cotton functional leaves showed positive correlation with double-bond index (DBI). These results suggested that salt stress caused DBI reduction and decreased the photochemical conversion efficiency of solar radiation and, thereby resulting in lower net photosynthetic rates.

  20. Compartmental analysis of renal physiology using nuclear medicine data and statistical optimization

    CERN Document Server

    Garbarino, Sara; Brignone, Massimo; Massollo, Michela; Sambuceti, Gianmario; Piana, Michele

    2012-01-01

    This paper describes a general approach to the compartmental modeling of nuclear data based on spectral analysis and statistical optimization. We utilize the renal physiology as test case and validate the method against both synthetic data and real measurements acquired during two micro-PET experiments with murine models.

  1. Physiological adaptation of maternal plasma volume during pregnancy: a systematic review and meta-analysis

    NARCIS (Netherlands)

    Haas, S.; Ghossein-Doha, C.; Kuijk, S.M. van; Drongelen, J. van; Spaanderman, M.E.A.

    2017-01-01

    OBJECTIVE: To describe the physiological pattern of gestational plasma volume adjustments in normal singleton pregnancy and compare this with the pattern in pregnancies complicated by pregnancy-induced hypertension, pre-eclampsia or fetal growth restriction. METHODS: We performed a meta-analysis of

  2. Quantum analysis of a plant metacommunity

    Directory of Open Access Journals (Sweden)

    Kürşad Özkan

    2016-01-01

    Full Text Available A wide variety of statistical methods have been frequently used in the area of ecology. Especially probability based analytic approaches have been become more popular in the ecological studies in recent years. On the other hand, the core of quantum is based on calculation of energy footprint by probability approach. That is why it has been expected that quantum analysis will have found a significant place in the ecological studies in the future. As a result, the book of quantum ecology written by László Orlóci Frsc made a profound contribution to enter within this process. This study aims at calculations of the potential energy footprints of specific processes including phylogeny, environmental mediation and emergent effects by using quantum analysis for a plant metacommunity. In this study, the fundamental formulate was based on Max Planck’s energy based entropy modified by László Orlóci Frsc. A plant metacommunity example includes 3 complexes taken from various slope positions of Yazılı Canyon Nature Park located in the Lake districts was subjected to quantum analysis. Energy structure parameters were calculated for each complex. Variations among the complexes’ H(cx energy footprints were found insignificant. Calculations at the level of catena was shown that potential energy footprint of phylogeny overwhelms the effect of slope position in the nH terms. However this is turned in favor of the slope position gradient when the H footprints are compared. In the study, stability values of the complexes were also calculated and, the highest instability value was found for the complex taken from valley bottom of the canyon.

  3. Measuring sap flow, and other plant physiological conditions across a soil salinity gradient in the lower Colorado River at Cibola National Wildlife Refuge: Vegetation and soil physiology linkages with microwave dielectric constant

    Science.gov (United States)

    McDonald, K. C.; Lasne, Y.; Schroeder, R.; Morino, K.; Hultine, K. R.; Nagler, P. L.

    2009-12-01

    We used ground measurements to examine stand structure and evapotranspiration of Tamarix in the Cibola National Wildlife Refuge (CNWR) on the Lower Colorado River. Three Tamarix study sites were established at different distances from the Colorado River on a river terrace in the CNWR. The sites were chosen from aerial photographs to represent typical dense stands of Tamarix within the CNWR. The sites were representative of differing saline environments, with each having ground water with distinct salt concentration levels. Wells were established at the site to establish depth to water and the salinity concentration within the ground water. We monitored xylem sap flow within each of the three stands. In addition we measured leaf area index to characterize canopy structure. We compared ET, foliage density, depth to water, and salinity among the Tamarix sites to examine stand-level variability driven by the variations in salinity. We supplemented these collections with measurements to characterize soil and vegetation microwave dielectric properties and their relationship to physiologic parameters. The dielectric properties of a material describe the interaction of an electric field with the material. Previous field experiments have demonstrated that varying degrees of correlation exist between vegetation dielectric properties and tree canopy water status. Temporal variation of the dielectric constant of woody plant tissue may result from changes in water status (e.g., water content) and chemical composition, albeit to varying degrees of sensitivity. The varying amount of ground water salinity at CNWR offers a unique opportunity to examine the relationship between vegetation and soil dielectric constant as related to vegetation ecophysiology. A field portable vector network analyzer is used to measure the microwave dielectric spectrum of the soil and vegetation Combined with measurements of vegetation xylem sap flux and soil chemistry, these measurements allow

  4. Physiological analysis and transcriptome comparison of two muskmelon (Cucumis melo L.) cultivars in response to salt stress.

    Science.gov (United States)

    Wang, L M; Zhang, L D; Chen, J B; Huang, D F; Zhang, Y D

    2016-09-19

    Melon (Cucumis melo L.) is an important vegetable crop that ranks second in salt tolerance among the Cucurbitaceae. Previous studies on the two muskmelon cultivars 'Bing XueCui' (BXC) and 'Yu Lu' (YL) revealed that they had different characteristics under salt stress, but the molecular basis underlying their different physiological responses is unclear. Here, we combined a physiological study with a genome-wide transcriptome analysis to understand the molecular basis of genetic variation that responds to salt stress in the melon. BXC performed better under salt stress than YL in terms of biomass and photosynthetic characteristics, because it exhibited less reduction in transpiration rate, net photosynthesis rate, and stomatal conductance under 150-mM NaCl stress than YL. A transcriptome comparison of the leaves of the cultivars revealed that 1171 genes responded to salt stress in BXC while 1487 genes were identified as salt-stress-responsive in YL. A real-time polymerase chain reaction analysis of 12 of the responsive genes revealed that there was a strong, positive correlation with RNA sequencing data. The genes were involved in several pathways, including photosynthesis, the biosynthesis of secondary metabolites, metabolism, and plant hormone signal transduction, and their expression levels differed between the two cultivars in response to salt stress. This study provides a molecular perspective of two melon cultivars in response to salt stress, and its results could be used to investigate the complex molecular mechanisms underlying salt tolerance in the melon.

  5. Martin Gibbs (1922-2006): Pioneer of (14)C research, sugar metabolism & photosynthesis; vigilant Editor-in-Chief of Plant Physiology; sage Educator; and humanistic Mentor.

    Science.gov (United States)

    Black, Clanton C

    2008-01-01

    The very personal touch of Professor Martin Gibbs as a worldwide advocate for photosynthesis and plant physiology was lost with his death in July 2006. Widely known for his engaging humorous personality and his humanitarian lifestyle, Martin Gibbs excelled as a strong international science diplomat; like a personal science family patriarch encouraging science and plant scientists around the world. Immediately after World War II he was a pioneer at the Brookhaven National Laboratory in the use of (14)C to elucidate carbon flow in metabolism and particularly carbon pathways in photosynthesis. His leadership on carbon metabolism and photosynthesis extended for four decades of working in collaboration with a host of students and colleagues. In 1962, he was selected as the Editor-in-Chief of Plant Physiology. That appointment initiated 3 decades of strong directional influences by Gibbs on plant research and photosynthesis. Plant Physiology became and remains a premier source of new knowledge about the vital and primary roles of plants in earth's environmental history and the energetics of our green-blue planet. His leadership and charismatic humanitarian character became the quintessence of excellence worldwide. Martin Gibbs was in every sense the personification of a model mentor not only for scientists but also shown in devotion to family. Here we pay tribute and honor to an exemplary humanistic mentor, Martin Gibbs.

  6. Reliability analysis of wastewater treatment plants.

    Science.gov (United States)

    Oliveira, Sílvia C; Von Sperling, Marcos

    2008-02-01

    This article presents a reliability analysis of 166 full-scale wastewater treatment plants operating in Brazil. Six different processes have been investigated, comprising septic tank+anaerobic filter, facultative pond, anaerobic pond+facultative pond, activated sludge, upflow anaerobic sludge blanket (UASB) reactors alone and UASB reactors followed by post-treatment. A methodology developed by Niku et al. [1979. Performance of activated sludge process and reliability-based design. J. Water Pollut. Control Assoc., 51(12), 2841-2857] is used for determining the coefficients of reliability (COR), in terms of the compliance of effluent biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP) and fecal or thermotolerant coliforms (FC) with discharge standards. The design concentrations necessary to meet the prevailing discharge standards and the expected compliance percentages have been calculated from the COR obtained. The results showed that few plants, under the observed operating conditions, would be able to present reliable performances considering the compliance with the analyzed standards. The article also discusses the importance of understanding the lognormal behavior of the data in setting up discharge standards, in interpreting monitoring results and compliance with the legislation.

  7. Joint control of terrestrial gross primary productivity by plant phenology and physiology

    DEFF Research Database (Denmark)

    Xia, Jianyang; Niu, Shuli; Ciais, Philippe

    2015-01-01

    –covariance and satellite-derived data, we decomposed annual terrestrial GPP into the length of the CO2 uptake period (CUP) and the seasonal maximal capacity of CO2 uptake (GPPmax). The product of CUP and GPPmax explained >90% of the temporal GPP variability in most areas of North America during 2000–2010 and the spatial...... GPP variation among globally distributed eddy flux tower sites. It also explained GPP response to the European heatwave in 2003 (r2 = 0.90) and GPP recovery after a fire disturbance in South Dakota (r2 = 0.88). Additional analysis of the eddy–covariance flux data shows that the interbiome variation...

  8. Seismic analysis of nuclear power plant structures

    Science.gov (United States)

    Go, J. C.

    1973-01-01

    Primary structures for nuclear power plants are designed to resist expected earthquakes of the site. Two intensities are referred to as Operating Basis Earthquake and Design Basis Earthquake. These structures are required to accommodate these seismic loadings without loss of their functional integrity. Thus, no plastic yield is allowed. The application of NASTRAN in analyzing some of these seismic induced structural dynamic problems is described. NASTRAN, with some modifications, can be used to analyze most structures that are subjected to seismic loads. A brief review of the formulation of seismic-induced structural dynamics is also presented. Two typical structural problems were selected to illustrate the application of the various methods of seismic structural analysis by the NASTRAN system.

  9. Thermodynamic Analysis of Combined Cycle Power Plant

    Directory of Open Access Journals (Sweden)

    A.K.Tiwari,

    2010-04-01

    Full Text Available Air Bottoming Cycle (ABC can replace the heat recovery steam generator and the steam turbine of the conventionalcombined cycle plant. The exhaust energy of the topping gas turbine of existing combine cycle is sent to gas-air heat exchange, which heats the air in the secondary gas turbine cycle. In 1980’s the ABC was proposed as an alternative for the conventional steam bottoming cycle. In spite of the cost of reducing hardware installations it could achieve a thermal efficiency of 80%. The complete thermodynamic analysis of the system has been performed by using specially designed programme, enabling the variation of main independent variables. The result shows the gain in net work output as well as efficiency of combined cycle is 35% to 68%.

  10. Waste Isolation Pilot Plant Safety Analysis Report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    The following provides a summary of the specific issues addressed in this FY-95 Annual Update as they relate to the CH TRU safety bases: Executive Summary; Site Characteristics; Principal Design and Safety Criteria; Facility Design and Operation; Hazards and Accident Analysis; Derivation of Technical Safety Requirements; Radiological and Hazardous Material Protection; Institutional Programs; Quality Assurance; and Decontamination and Decommissioning. The System Design Descriptions`` (SDDS) for the WIPP were reviewed and incorporated into Chapter 3, Principal Design and Safety Criteria and Chapter 4, Facility Design and Operation. This provides the most currently available final engineering design information on waste emplacement operations throughout the disposal phase up to the point of permanent closure. Also, the criteria which define the TRU waste to be accepted for disposal at the WIPP facility were summarized in Chapter 3 based on the WAC for the Waste Isolation Pilot Plant.`` This Safety Analysis Report (SAR) documents the safety analyses that develop and evaluate the adequacy of the Waste Isolation Pilot Plant Contact-Handled Transuranic Wastes (WIPP CH TRU) safety bases necessary to ensure the safety of workers, the public and the environment from the hazards posed by WIPP waste handling and emplacement operations during the disposal phase and hazards associated with the decommissioning and decontamination phase. The analyses of the hazards associated with the long-term (10,000 year) disposal of TRU and TRU mixed waste, and demonstration of compliance with the requirements of 40 CFR 191, Subpart B and 40 CFR 268.6 will be addressed in detail in the WIPP Final Certification Application scheduled for submittal in October 1996 (40 CFR 191) and the No-Migration Variance Petition (40 CFR 268.6) scheduled for submittal in June 1996. Section 5.4, Long-Term Waste Isolation Assessment summarizes the current status of the assessment.

  11. Analysis of Physiological, Technical, and Tactical Analysis during a Friendly Football Match of Elite U19

    Directory of Open Access Journals (Sweden)

    Juan Ignacio Ortega

    2016-06-01

    Full Text Available The main objective was to analyze a friendly match of youth elite soccer players identifying the variance of tactical and physiological response parameters during the game. In addition, detecting the impact of both halves on player performance. For the purposes of this study twenty-two U19 players were analyzed playing 11v11. Activity profile, heart rate (HR and HRmax, grouped in five different zones were analyzed via Bluetooth technology, technical performance was analyzed by the Team Sport Assessment Procedure (TSAP, and tactical performance was measured by Social Network Analysis. A comparison of heart rate responses showed significant main effects in the halves (p = 0.001; η p 2 = 0.623. A comparison between tactical position and technical performance had significant main effects (p = 0.001; η p 2 = 0.390. Tactical position showed statistically significant effects on tactical prominence (p = 0.002; η p 2 = 0.296. Therefore, fatigue is a component distinguished in technical/tactical parameters, such as volume of play and efficiency index. Results suggest that fatigue effects may constrain technical performance and, for that reason, the use of instruments to monitor the fatigue effect during matches may be suggested.

  12. Plant databases and data analysis tools

    Science.gov (United States)

    It is anticipated that the coming years will see the generation of large datasets including diagnostic markers in several plant species with emphasis on crop plants. To use these datasets effectively in any plant breeding program, it is essential to have the information available via public database...

  13. Exogenously Applied Plant Growth Regulators Enhance the Morpho-Physiological Growth and Yield of Rice under High Temperature.

    Science.gov (United States)

    Fahad, Shah; Hussain, Saddam; Saud, Shah; Hassan, Shah; Ihsan, Zahid; Shah, Adnan N; Wu, Chao; Yousaf, Muhammad; Nasim, Wajid; Alharby, Hesham; Alghabari, Fahad; Huang, Jianliang

    2016-01-01

    A 2-year experiment was conducted to ascertain the effects of exogenously applied plant growth regulators (PGR) on rice growth and yield attributes under high day (HDT) and high night temperature (HNT). Two rice cultivars (IR-64 and Huanghuazhan) were subjected to temperature treatments in controlled growth chambers and four different combinations of ascorbic acid (Vc), alpha-tocopherol (Ve), brassinosteroids (Br), methyl jasmonates (MeJA), and triazoles (Tr) were applied. High temperature severely affected rice morphology, and also reduced leaf area, above-, and below-ground biomass, photosynthesis, and water use efficiency, while increased the leaf water potential of both rice cultivars. Grain yield and its related attributes except number of panicles, were reduced under high temperature. The HDT posed more negative effects on rice physiological attributes, while HNT was more detrimental for grain formation and yield. The Huanghuazhan performed better than IR-64 under high temperature stress with better growth and higher grain yield. Exogenous application of PGRs was helpful in alleviating the adverse effects of high temperature. Among PGR combinations, the Vc+Ve+MejA+Br was the most effective treatment for both cultivars under high temperature stress. The highest grain production by Vc+Ve+MejA+Br treated plants was due to enhanced photosynthesis, spikelet fertility and grain filling, which compensated the adversities of high temperature stress. Taken together, these results will be of worth for further understanding the adaptation and survival mechanisms of rice to high temperature and will assist in developing heat-resistant rice germplasm in future.

  14. Exogenously applied plant growth regulators enhance the morpho-physiological growth and yield of rice under high temperature

    Directory of Open Access Journals (Sweden)

    Shah Fahad

    2016-08-01

    Full Text Available A two-year experiment was conducted to ascertain the effects of exogenously applied plant growth regulators (PGR on rice growth and yield attributes under high day (HDT and high night temperature (HNT. Two rice cultivars (IR-64 and Huanghuazhan were subjected to temperature treatments in controlled growth chambers and four different combinations of ascorbic acid (Vc, alpha-tocopherol (Ve, brassinosteroids (Br, methyl jasmonates (MeJA and triazoles (Tr were applied. High temperature severely affected rice morphology, and also reduced leaf area, above- and below-ground biomass, photosynthesis, and water use efficiency, while increased the leaf water potential of both rice cultivars. Grain yield and its related attributes except number of panicles, were reduced under high temperature. The HDT posed more negative effects on rice physiological attributes, while HNT was more detrimental for grain formation and yield. The Huanghuazhan performed better than IR-64 under high temperature stress with better growth and higher grain yield. Exogenous application of PGRs was helpful in alleviating the adverse effects of high temperature. Among PGR combinations, the Vc+Ve+MejA+Br was the most effective treatment for both cultivars under high temperature stress. The highest grain production by Vc+Ve+MejA+Br treated plants was due to enhanced photosynthesis, spikelet fertility and grain filling, which compensated the adversities of high temperature stress. Taken together, these results will be of worth for further understanding the adaptation and survival mechanisms of rice to high temperature and will assist in developing heat-resistant rice germplasm in future.

  15. A self-referencing biosensor for real-time monitoring of physiological ATP transport in plant systems.

    Science.gov (United States)

    Vanegas, Diana C; Clark, Greg; Cannon, Ashley E; Roux, Stanley; Chaturvedi, Prachee; McLamore, Eric S

    2015-12-15

    The objective of this study was to develop a self-referencing electrochemical biosensor for the direct measurement of ATP flux into the extracellular matrix by living cells/organisms. The working mechanism of the developed biosensor is based on the activity of glycerol kinase and glycerol-3-phosphate oxidase. A stratified bi-enzyme nanocomposite was created using a protein-templated silica sol gel encapsulation technique on top of graphene-modified platinum electrodes. The biosensor exhibited excellent electrochemical performance with a sensitivity of 2.4±1.8 nA/µM, a response time of 20±13 s and a lower detection limit of 1.3±0.7 nM. The self-referencing biosensor was used to measure exogenous ATP efflux by (i) germinating Ceratopteris spores and (ii) growing Zea mays L. roots. This manuscript demonstrates the first development of a non-invasive ATP micro-biosensor for the direct measurement of eATP transport in living tissues. Before this work, assays of eATP have not been able to record the temporally transient movement of ATP at physiological levels (nM and sub-nM). The method demonstrated here accurately measured [eATP] flux in the immediate vicinity of plant cells. Although these proof of concept experiments focus on plant tissues, the technique developed herein is applicable to any living tissue, where nanomolar concentrations of ATP play a critical role in signaling and development. This tool will be invaluable for conducting hypothesis-driven life science research aimed at understanding the role of ATP in the extracellular environment.

  16. A method for quantitative analysis of spatially variable physiological processes across leaf surfaces.

    Science.gov (United States)

    Aldea, Mihai; Frank, Thomas D; DeLucia, Evan H

    2006-11-01

    Many physiological processes are spatially variable across leaf surfaces. While maps of photosynthesis, stomatal conductance, gene expression, water transport, and the production of reactive oxygen species (ROS) for individual leaves are readily obtained, analytical methods for quantifying spatial heterogeneity and combining information gathered from the same leaf but with different instruments are not widely used. We present a novel application of tools from the field of geographical imaging to the multivariate analysis of physiological images. Procedures for registration and resampling, cluster analysis, and classification provide a general framework for the analysis of spatially resolved physiological data. Two experiments were conducted to illustrate the utility of this approach. Quantitative analysis of images of chlorophyll fluorescence and the production of ROS following simultaneous exposure of soybean leaves to atmospheric O3 and soybean mosaic virus revealed that areas of the leaf where the operating quantum efficiency of PSII was depressed also experienced an accumulation of ROS. This correlation suggests a causal relationship between oxidative stress and inhibition of photosynthesis. Overlaying maps of leaf surface temperature and chlorophyll fluorescence following a photoinhibition treatment indicated that areas with low operating quantum efficiency of PSII also experienced reduced stomatal conductance (high temperature). While each of these experiments explored the covariance of two processes by overlaying independent images gathered with different instruments, the same procedures can be used to analyze the covariance of information from multiple images. The application of tools from geographic image analysis to physiological processes occurring over small spatial scales will help reveal the mechanisms generating spatial variation across leaves.

  17. Multivariate analysis of physiological parameters reveals a consistent O3 response pattern in leaves of adult European beech (Fagus sylvatica).

    Science.gov (United States)

    Löw, Markus; Deckmyn, Gaby; Op de Beeck, Maarten; Blumenröther, Manuela C; Oßwald, Wolfgang; Alexou, Maria; Jehnes, Sascha; Haberer, Kristine; Rennenberg, Heinz; Herbinger, Karin; Häberle, Karl-Heinz; Bahnweg, Günther; Hanke, David; Wieser, Gerhard; Ceulemans, Reinhart; Matyssek, Rainer; Tausz, Michael

    2012-10-01

    • Increasing atmospheric concentrations of phytotoxic ozone (O(3) ) can constrain growth and carbon sink strength of forest trees, potentially exacerbating global radiative forcing. Despite progress in the conceptual understanding of the impact of O(3) on plants, it is still difficult to detect response patterns at the leaf level. • Here, we employed principal component analysis (PCA) to analyse a database containing physiological leaf-level parameters of 60-yr-old Fagus sylvatica (European beech) trees. Data were collected over two climatically contrasting years under ambient and twice-ambient O(3) regimes in a free-air forest environment. • The first principal component (PC1) of the PCA was consistently responsive to O(3) and crown position within the trees over both years. Only a few of the original parameters showed an O(3) effect. PC1 was related to parameters indicative of oxidative stress signalling and changes in carbohydrate metabolism. PC1 correlated with cumulative O(3) uptake over preceding days. • PC1 represents an O(3) -responsive multivariate pattern detectable in the absence of consistently measurable O(3) effects on individual leaf-level parameters. An underlying effect of O(3) on physiological processes is indicated, providing experimental confirmation of theoretical O(3) response patterns suggested previously.

  18. Observed and simulated effect of plant physiology and structure on land surface energy fluxes and soil conditions

    Science.gov (United States)

    Lu, Yen-Sen; Rihani, Jehan; Langensiepen, Matthias; Simmer, Clemens

    2016-04-01

    The parameterization of stomatal conductance and leaf area index (LAI) in land surface models largely influence simulated terrestrial system states. While stomatal conductance mainly controls transpiration, latent heat flux, and root-water-uptake, LAI impacts additionally the radiative energy exchange. Thus both affect canopy evaporation and transpiration and land surface energy and water fluxes as a whole. Common parameterizations of stomatal conductance follow either semi-mechanistic forms based on photosynthesis (Ball-Berry Type (BB)) or forms which consider environmental factors such as impact of light, temperature, humidity and soil moisture (Jarvis-Stewart Type (JS)). Both approaches differ also in the interpretation of humidity effects and light-use efficiency. While soil moisture plays an important role for root-water-uptake there is no clear conclusion yet about how soil moisture interacts with stomata activity. Values for LAI can be obtained from field measurements, satellite estimates or modelling and are used as an essential model input. While field measurements are very time consuming and only represent single points, satellite estimates may have biases caused by variable albedo and sensor limitations. Representing LAI within land surface models requires complex schemes in order to represent all processes contributing to plant growth. We use the Terrestrial System Modelling Platform (TerrSysMP) over the Rur watershed in Germany for studying the influence of plant physiology and structure on the state of the terrestrial system. The Transregional Collaborative Research Center 32 (TR32) extensively monitors this catchment for almost a decade. The land surface (CLM3.5) and the subsurface (ParFlow) modules of TerrSysMP are conditioned based on satellite-retrieved land cover and the soil map from FAO and forced with a high-resolution reanalysis by DWD. For studying the effect of plant physiology, the Ball-Berry-Leuning, and Jarvis-Stewart stomatal

  19. Cistus creticus subsp. eriocephalus as a Model for Studying Plant Physiological and Metabolic Responses to Environmental Stress Factors.

    Science.gov (United States)

    Paolessi, Paola; Nicoletti, Marcello; Catoni, Rosangela; Puglielli, Giacomo; Toniolo, Chiara; Gratani, Loretta

    2015-12-01

    Variations in physiology and metabolic products of Cistus creticus subsp. eriocephalus along an altitudinal gradient (350-750 m.a.s.l.) within the Monti Lucretili Regional Natural Park (central Italy) were studied. The results showed that the phenol production was in relationship with the net photosynthetic rates and the chlorophyll content. In particular, the increasing caffeic acid (CA) content with altitude suggested its role in providing an additional photo-protection mechanism, by its ability to consume photochemical reducing power and acting as an alternative C-atom sink under high light conditions. The metabolic production was tested by high performance thin layer chromatography (HPTLC) fingerprint analysis, highlighting the potential of this technique in biologic studies. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

  20. Arbuscular mycorrhizal symbiosis regulates physiology and performance of Digitaria eriantha plants subjected to abiotic stresses by modulating antioxidant and jasmonate levels.

    Science.gov (United States)

    Pedranzani, H; Rodríguez-Rivera, M; Gutiérrez, M; Porcel, R; Hause, B; Ruiz-Lozano, J M

    2016-02-01

    This study evaluates antioxidant responses and jasmonate regulation in Digitaria eriantha cv. Sudafricana plants inoculated (AM) and non-inoculated (non-AM) with Rhizophagus irregularis and subjected to drought, cold, or salinity. Stomatal conductance, photosynthetic efficiency, biomass production, hydrogen peroxide accumulation, lipid peroxidation, antioxidants enzymes activities, and jasmonate levels were determined. Stomatal conductance and photosynthetic efficiency decreased in AM and non-AM plants under all stress conditions. However, AM plants subjected to drought, salinity, or non-stress conditions showed significantly higher stomatal conductance values. AM plants subjected to drought or non-stress conditions increased their shoot/root biomass ratios, whereas salinity and cold caused a decrease in these ratios. Hydrogen peroxide accumulation, which was high in non-AM plant roots under all treatments, increased significantly in non-AM plant shoots under cold stress and in AM plants under non-stress and drought conditions. Lipid peroxidation increased in the roots of all plants under drought conditions. In shoots, although lipid peroxidation decreased in AM plants under non-stress and cold conditions, it increased under drought and salinity. AM plants consistently showed high catalase (CAT) and ascorbate peroxidase (APX) activity under all treatments. By contrast, the glutathione reductase (GR) and superoxide dismutase (SOD) activity of AM roots was lower than that of non-AM plants and increased in shoots. The endogenous levels of cis-12-oxophytodienoc acid (OPDA), jasmonic acid (JA), and 12-OH-JA showed a significant increase in AM plants as compared to non-AM plants. 11-OH-JA content only increased in AM plants subjected to drought. Results show that D. eriantha is sensitive to drought, salinity, and cold stresses and that inoculation with AM fungi regulates its physiology and performance under such conditions, with antioxidants and jasmonates being involved

  1. Cluster-based analysis for personalized stress evaluation using physiological signals.

    Science.gov (United States)

    Xu, Qianli; Nwe, Tin Lay; Guan, Cuntai

    2015-01-01

    Technology development in wearable sensors and biosignal processing has made it possible to detect human stress from the physiological features. However, the intersubject difference in stress responses presents a major challenge for reliable and accurate stress estimation. This research proposes a novel cluster-based analysis method to measure perceived stress using physiological signals, which accounts for the intersubject differences. The physiological data are collected when human subjects undergo a series of task-rest cycles, incurring varying levels of stress that is indicated by an index of the State Trait Anxiety Inventory. Next, a quantitative measurement of stress is developed by analyzing the physiological features in two steps: 1) a k -means clustering process to divide subjects into different categories (clusters), and 2) cluster-wise stress evaluation using the general regression neural network. Experimental results show a significant improvement in evaluation accuracy as compared to traditional methods without clustering. The proposed method is useful in developing intelligent, personalized products for human stress management.

  2. Application of meta-transcriptomics and –proteomics to analysis of in situ physiological state

    Directory of Open Access Journals (Sweden)

    Allan eKonopka

    2012-05-01

    Full Text Available Analysis of the growth-limiting factor or environmental stressors affecting microbes in situ is of fundamental importance but analytically difficult. Microbes can reduce in situ limiting nutrient concentrations to sub-micromolar levels, and contaminated ecosystems may contain multiple stressors. The patterns of gene or protein expression by microbes in nature can be used to infer growth limitations, because they are regulated in response to environmental conditions. Experimental studies under controlled conditions in the laboratory provide the physiological underpinnings for developing these physiological indicators. Although regulatory networks may differ among specific microbes, there are some broad principles that can be applied, related to limiting nutrient acquisition, resource allocation, and stress responses. As technologies for transcriptomics and proteomics mature, the capacity to apply these approaches to complex microbial communities will accelerate. In particular, global proteomics reflect expressed catalytic activities. Furthermore, the high mass accuracy of some proteomic approaches allows mapping back to specific microbial strains. For example, at the Rifle IFRC field site in Western Colorado, the physiological status of Fe(III-reducing populations has been tracked over time. Members of a subsurface clade within the Geobacter predominated during carbon amendment to the subsurface environment. At the functional level, proteomic identifications produced inferences regarding (i temporal changes in anabolism and catabolism of acetate, (ii the onset of N2 fixation when N became limiting, and (iii expression of phosphate transporters during periods of intense growth. The application of these approaches in situ can lead to discovery of novel physiological adaptations.

  3. Analysis of gene expression and physiological responses in three Mexican maize landraces under drought stress and recovery irrigation.

    Directory of Open Access Journals (Sweden)

    Corina Hayano-Kanashiro

    Full Text Available BACKGROUND: Drought is one of the major constraints for plant productivity worldwide. Different mechanisms of drought-tolerance have been reported for several plant species including maize. However, the differences in global gene expression between drought-tolerant and susceptible genotypes and their relationship to physiological adaptations to drought are largely unknown. The study of the differences in global gene expression between tolerant and susceptible genotypes could provide important information to design more efficient breeding programs to produce maize varieties better adapted to water limiting conditions. METHODOLOGY/PRINCIPAL FINDINGS: Changes in physiological responses and gene expression patterns were studied under drought stress and recovery in three Mexican maize landraces which included two drought tolerant (Cajete criollo and Michoacán 21 and one susceptible (85-2 genotypes. Photosynthesis, stomatal conductance, soil and leaf water potentials were monitored throughout the experiment and microarray analysis was carried out on transcripts obtained at 10 and 17 days following application of stress and after recovery irrigation. The two tolerant genotypes show more drastic changes in global gene expression which correlate with different physiological mechanisms of adaptation to drought. Differences in the kinetics and number of up- and down-regulated genes were observed between the tolerant and susceptible maize genotypes, as well as differences between the two tolerant genotypes. Interestingly, the most dramatic differences between the tolerant and susceptible genotypes were observed during recovery irrigation, suggesting that the tolerant genotypes activate mechanisms that allow more efficient recovery after a severe drought. CONCLUSIONS/SIGNIFICANCE: A correlation between levels of photosynthesis and transcription under stress was observed and differences in the number, type and expression levels of transcription factor

  4. Genomic and physiological analysis reveals versatile metabolic capacity of deep-sea Photobacterium phosphoreum ANT-2200.

    Science.gov (United States)

    Zhang, Sheng-Da; Santini, Claire-Lise; Zhang, Wei-Jia; Barbe, Valérie; Mangenot, Sophie; Guyomar, Charlotte; Garel, Marc; Chen, Hai-Tao; Li, Xue-Gong; Yin, Qun-Jian; Zhao, Yuan; Armengaud, Jean; Gaillard, Jean-Charles; Martini, Séverine; Pradel, Nathalie; Vidaud, Claude; Alberto, François; Médigue, Claudine; Tamburini, Christian; Wu, Long-Fei

    2016-05-01

    Bacteria of the genus Photobacterium thrive worldwide in oceans and show substantial eco-physiological diversity including free-living, symbiotic and piezophilic life styles. Genomic characteristics underlying this variability across species are poorly understood. Here we carried out genomic and physiological analysis of Photobacterium phosphoreum strain ANT-2200, the first deep-sea luminous bacterium of which the genome has been sequenced. Using optical mapping we updated the genomic data and reassembled it into two chromosomes and a large plasmid. Genomic analysis revealed a versatile energy metabolic potential and physiological analysis confirmed its growth capacity by deriving energy from fermentation of glucose or maltose, by respiration with formate as electron donor and trimethlyamine N-oxide (TMAO), nitrate or fumarate as electron acceptors, or by chemo-organo-heterotrophic growth in rich media. Despite that it was isolated at a site with saturated dissolved oxygen, the ANT-2200 strain possesses four gene clusters coding for typical anaerobic enzymes, the TMAO reductases. Elevated hydrostatic pressure enhances the TMAO reductase activity, mainly due to the increase of isoenzyme TorA1. The high copy number of the TMAO reductase isoenzymes and pressure-enhanced activity might imply a strategy developed by bacteria to adapt to deep-sea habitats where the instant TMAO availability may increase with depth.

  5. Genome-Guided Insights into the Plant Growth Promotion Capabilities of the Physiologically Versatile Bacillus aryabhattai Strain AB211

    Science.gov (United States)

    Bhattacharyya, Chandrima; Bakshi, Utpal; Mallick, Ivy; Mukherji, Shayantan; Bera, Biswajit; Ghosh, Abhrajyoti

    2017-01-01

    Bacillus aryabhattai AB211 is a plant growth promoting, Gram-positive firmicute, isolated from the rhizosphere of tea (Camellia sinensis), one of the oldest perennial crops and a major non-alcoholic beverage widely consumed all over the world. The whole genome of B. aryabhattai AB211 was sequenced, annotated and evaluated with special focus on genomic elements related to plant microbe interaction. It’s genome sequence reveals the presence of a 5,403,026 bp chromosome. A total of 5226 putative protein-coding sequences, 16 rRNA, 120 tRNA, 8 ncRNAs, 58 non-protein coding genes, and 11 prophage regions were identified. Genome sequence comparisons between strain AB211 and other related environmental strains of B. aryabhattai, identified about 3558 genes conserved among all B. aryabhattai genomes analyzed. Most of the common genes involved in plant growth promotion activities were found to be present within core genes of all the genomes used for comparison, illustrating possible common plant growth promoting traits shared among all the strains of B. aryabhattai. Besides the core genes, some genes were exclusively identified in the genome of strain AB211. Functional annotation of the genes predicted in the strain AB211 revealed the presence of genes responsible for mineral phosphate solubilization, siderophores, acetoin, butanediol, exopolysaccharides, flagella biosynthesis, surface attachment/biofilm formation, and indole acetic acid production, most of which were experimentally verified in the present study. Genome analysis and experimental evidence suggested that AB211 has robust central carbohydrate metabolism implying that this bacterium can efficiently utilize the root exudates and other organic materials as an energy source. Genes for the production of peroxidases, catalases, and superoxide dismutases, that confer resistance to oxidative stresses in plants were identified in AB211 genome. Besides these, genes for heat shock tolerance, cold shock tolerance

  6. Image analysis in the evaluation of the physiological potential of maize seeds1

    Directory of Open Access Journals (Sweden)

    Crislaine Aparecida Gomes Pinto

    Full Text Available The Seed Analysis System (SAS is used in the image analysis of seeds and seedlings, and has the potential for use in the control of seed quality. The aim of this research was to adapt the methodology of image analysis of maize seedlings by SAS, and to verify the potential use of this equipment in the evaluation of the physiological potential of maize seeds. Nine batches of two maize hybrids were characterised by means of the following tests and determinations: germination, first count, accelerated ageing, cold test, seedling emergence at 25 and 30ºC, and speed of emergence index. The image analysis experiment was carried out in a factorial scheme of 9 batches x 4 methods of analysis of the seedling images (with and without the use of NWF as substrate, and with and without manual correction of the images. Images of the seedlings were evaluated using the average lengths of the coleoptile, roots and seedlings; and by the automatic and manual indices of vigour, uniformity and growth produced by the SAS. Use of blue NWF afffects the initial development of maize seedlings. The physiological potential of maize seeds can be evaluated in seedlings which are seeded on white paper towels at a temperature of 25 °C and evaluated on the third day. Image analysis should be carried out with the SAS software using automatic calibration and with no correction of the seedling images. Use of SAS equipment for the analysis of seedling images is a potential tool in evaluating the physiological quality of maize seeds.

  7. Relay Feedback Analysis for Double Integral Plants

    Directory of Open Access Journals (Sweden)

    Zhen Ye

    2011-01-01

    Full Text Available Double integral plants under relay feedback are studied. Complete results on the uniqueness of solutions, existence, and stability of the limit cycles are established using the point transformation method. Analytical expressions are also given for determining the amplitude and period of a limit cycle from the plant parameters.

  8. Physiology of Pseudomonas aeruginosa in biofilms as revealed by transcriptome analysis

    Directory of Open Access Journals (Sweden)

    Parker Albert

    2010-11-01

    Full Text Available Abstract Background Transcriptome analysis was applied to characterize the physiological activities of Pseudomonas aeruginosa grown for three days in drip-flow biofilm reactors. Conventional applications of transcriptional profiling often compare two paired data sets that differ in a single experimentally controlled variable. In contrast this study obtained the transcriptome of a single biofilm state, ranked transcript signals to make the priorities of the population manifest, and compared ranki ngs for a priori identified physiological marker genes between the biofilm and published data sets. Results Biofilms tolerated exposure to antibiotics, harbored steep oxygen concentration gradients, and exhibited stratified and heterogeneous spatial patterns of protein synthetic activity. Transcriptional profiling was performed and the signal intensity of each transcript was ranked to gain insight into the physiological state of the biofilm population. Similar rankings were obtained from data sets published in the GEO database http://www.ncbi.nlm.nih.gov/geo. By comparing the rank of genes selected as markers for particular physiological activities between the biofilm and comparator data sets, it was possible to infer qualitative features of the physiological state of the biofilm bacteria. These biofilms appeared, from their transcriptome, to be glucose nourished, iron replete, oxygen limited, and growing slowly or exhibiting stationary phase character. Genes associated with elaboration of type IV pili were strongly expressed in the biofilm. The biofilm population did not indicate oxidative stress, homoserine lactone mediated quorum sensing, or activation of efflux pumps. Using correlations with transcript ranks, the average specific growth rate of biofilm cells was estimated to be 0.08 h-1. Conclusions Collectively these data underscore the oxygen-limited, slow-growing nature of the biofilm population and are consistent with antimicrobial tolerance due

  9. Quantitative Fluorimetric Analysis of Plant Nicotinamide

    Institute of Scientific and Technical Information of China (English)

    王泽斌; 冯闻铮; 曹竹安; 刘进元

    2001-01-01

    Fluorimetry was used to measure the amount of nicotinamide in plant samples. The nicotinamide was extracted and purified from plant tissues with ethyl acetate; converted to the fluorescent derivative, N1-methylnicotinamide, by reacting with methyl iodide; and quantified according to its fluorescent strength. The nicotinamide in the leaf tissue of ten kinds of plants was measured, and the results showed that the nicotinamide content for different plants varied from 0. 1 to 3.0 μg/g of fresh leaf weight. In addition, the crossing value of the fluorescent strength and the nicotinamide amount demonstrated that the linear correlation coefficient generally reached 0. 997, with a detectable limit of 0. 02 mg/L and the relative standard deviation of less than 9%. The results suggested that this method of quantifying nicotinamide in plants is useful and beneficial for functional research.

  10. PlantPAN 2.0: an update of plant promoter analysis navigator for reconstructing transcriptional regulatory networks in plants.

    Science.gov (United States)

    Chow, Chi-Nga; Zheng, Han-Qin; Wu, Nai-Yun; Chien, Chia-Hung; Huang, Hsien-Da; Lee, Tzong-Yi; Chiang-Hsieh, Yi-Fan; Hou, Ping-Fu; Yang, Tien-Yi; Chang, Wen-Chi

    2016-01-01

    Transcription factors (TFs) are sequence-specific DNA-binding proteins acting as critical regulators of gene expression. The Plant Promoter Analysis Navigator (PlantPAN; http://PlantPAN2.itps.ncku.edu.tw) provides an informative resource for detecting transcription factor binding sites (TFBSs), corresponding TFs, and other important regulatory elements (CpG islands and tandem repeats) in a promoter or a set of plant promoters. Additionally, TFBSs, CpG islands, and tandem repeats in the conserve regions between similar gene promoters are also identified. The current PlantPAN release (version 2.0) contains 16 960 TFs and 1143 TF binding site matrices among 76 plant species. In addition to updating of the annotation information, adding experimentally verified TF matrices, and making improvements in the visualization of transcriptional regulatory networks, several new features and functions are incorporated. These features include: (i) comprehensive curation of TF information (response conditions, target genes, and sequence logos of binding motifs, etc.), (ii) co-expression profiles of TFs and their target genes under various conditions, (iii) protein-protein interactions among TFs and their co-factors, (iv) TF-target networks, and (v) downstream promoter elements. Furthermore, a dynamic transcriptional regulatory network under various conditions is provided in PlantPAN 2.0. The PlantPAN 2.0 is a systematic platform for plant promoter analysis and reconstructing transcriptional regulatory networks.

  11. GenoCAD Plant Grammar to Design Plant Expression Vectors for Promoter Analysis.

    Science.gov (United States)

    Coll, Anna; Wilson, Mandy L; Gruden, Kristina; Peccoud, Jean

    2016-01-01

    With the rapid advances in prediction tools for discovery of new promoters and their cis-elements, there is a need to improve plant expression methodologies in order to facilitate a high-throughput functional validation of these promoters in planta. The promoter-reporter analysis is an indispensible approach for characterization of plant promoters. It requires the design of complex plant expression vectors, which can be challenging. Here, we describe the use of a plant grammar implemented in GenoCAD that will allow the users to quickly design constructs for promoter analysis experiments but also for other in planta functional studies. The GenoCAD plant grammar includes a library of plant biological parts organized in structural categories to facilitate their use and management and a set of rules that guides the process of assembling these biological parts into large constructs.

  12. Plastidic isoprenoid biosynthesis in tomato: physiological and molecular analysis in genotypes resistant and sensitive to drought stress.

    Science.gov (United States)

    Loyola, J; Verdugo, I; González, E; Casaretto, J A; Ruiz-Lara, S

    2012-01-01

    Isoprenoid compounds synthesised in the plastids are involved in plant response to water deficit. The functionality of the biosynthetic pathway of these compounds under drought stress has been analysed at the physiological and molecular levels in two related species of tomato (Solanum chilense and Solanum lycopersicum) that differ in their tolerance to abiotic challenge. Expression analysis of the genes encoding enzymes of these pathways (DXS, IPI, GGPPS, PSY1, NCED and HPT1) in plants at different RWC values shows significant differences for only GGPPS and HPT1, with higher expression in the tolerant S. chilense. Chlorophyll, carotenoids, α-tocopherol and ABA content was also determined in both species under different drought conditions. In agreement with HPT1 transcriptional activity, higher α-tocopherol content was observed in S. chilense than in S. lycopersicum, which correlates with a lower degree of lipoperoxidation in the former species. These results suggest that, in addition to lower stomatal conductance, α-tocopherol biosynthesis is part of the adaptation mechanisms of S. chilense to adverse environmental conditions.

  13. Vital analysis: annotating sensed physiological signals with the stress levels of first responders in action.

    Science.gov (United States)

    Gomes, P; Kaiseler, M; Queirós, C; Oliveira, M; Lopes, B; Coimbra, M

    2012-01-01

    First responders such as firefighters are exposed to extreme stress and fatigue situations during their work routines. It is thus desirable to monitor their health using wearable sensing but this is a complex and still unsolved research challenge that requires large amounts of properly annotated physiological signals data. In this paper we show that the information gathered by our Vital Analysis Framework can support the annotation of these vital signals with the stress levels perceived by the target user, confirmed by the analysis of more than 4600 hours of data collected from real firefighters in action, including 717 answers to event questionnaires from a total of 454 different events.

  14. Molecular and biochemical analysis of symbiotic plant receptor kinase complexes

    Energy Technology Data Exchange (ETDEWEB)

    Cook, Douglas R; Riely, Brendan K

    2010-09-01

    DE-FG02-01ER15200 was a 36-month project, initiated on Sept 1, 2005 and extended with a one-year no cost extension to August 31, 2009. During the project period we published seven manuscripts (2 in review). Including the prior project period (2002-2005) we published 12 manuscripts in journals that include Science, PNAS, The Plant Cell, Plant Journal, Plant Physiology, and MPMI. The primary focus of this work was to further elucidate the function of the Nod factor signaling pathway that is involved in initiation of the legume-rhizobium symbiosis and in particular to explore the relationship between receptor kinase-like proteins and downstream effectors of symbiotic development. During the project period we have map-base cloned two additional players in symbiotic development, including an ERF transcription factor and an ethylene pathway gene (EIN2) that negatively regulates symbiotic signaling; we have also further characterized the subcellular distribution and function of a nuclear-localized symbiosis-specific ion channel, DMI1. The major outcome of the work has been the development of systems for exploring and validating protein-protein interactions that connect symbiotic receptor-like proteins to downstream responses. In this regard, we have developed both homologous (i.e., in planta) and heterologous (i.e., in yeast) systems to test protein interactions. Using yeast 2-hybrid screens we isolated the only known interactor of the nuclear-localized calcium-responsive kinase DMI3. We have also used yeast 2-hybrid methodology to identify interactions between symbiotic signaling proteins and certain RopGTPase/RopGEF proteins that regulate root hair polar growth. More important to the long-term goals of our work, we have established a TAP tagging system that identifies in planta interactions based on co-immuno precipitation and mass spectrometry. The validity of this approach has been shown using known interactors that either co-iummnoprecipate (i.e., remorin) or co

  15. Transcriptomic and physiological responses to fishmeal substitution with plant proteins in formulated feed in farmed Atlantic salmon (Salmo salar

    Directory of Open Access Journals (Sweden)

    Tacchi Luca

    2012-08-01

    Full Text Available Abstract Background Aquaculture of piscivorous fish is in continual expansion resulting in a global requirement to reduce the dependence on wild caught fish for generation of fishmeal and fish oil. Plant proteins represent a suitable protein alternative to fish meal and are increasingly being used in fish feed. In this study, we examined the transcriptional response of Atlantic salmon (Salmo salar to a high marine protein (MP or low fishmeal, higher plant protein replacement diet (PP, formulated to the same nutritional specification within previously determined acceptable maximum levels of individual plant feed materials. Results After 77 days of feeding the fish in both groups doubled in weight, however neither growth performance, feed efficiency, condition factor nor organ indices were significantly different. Assessment of histopathological changes in the heart, intestine or liver did not reveal any negative effects of the PP diet. Transcriptomic analysis was performed in mid intestine, liver and skeletal muscle, using an Atlantic salmon oligonucleotide microarray (Salar_2, Agilent 4x44K. The dietary comparison revealed large alteration in gene expression in all the tissues studied between fish on the two diets. Gene ontology analysis showed, in the mid intestine of fish fed PP, higher expression of genes involved in enteritis, protein and energy metabolism, mitochondrial activity/kinases and transport, and a lower expression of genes involved in cell proliferation and apoptosis compared to fish fed MP. The liver of fish fed PP showed a lower expression of immune response genes but a higher expression of cell proliferation and apoptosis processes that may lead to cell reorganization in this tissue. The skeletal muscle of fish fed PP vs MP was characterized by a suppression of processes including immune response, energy and protein metabolism, cell proliferation and apoptosis which may reflect a more energy efficient tissue. Conclusions The PP

  16. The assessment of neural injury following open heart surgery by physiological tremor analysis.

    Science.gov (United States)

    Németh, Adám; Hejjel, László; Ajtay, Zénó; Kellényi, Lóránd; Solymos, Andor; Bártfai, Imre; Kovács, Norbert; Lenkey, Zsófia; Cziráki, Attila; Szabados, Sándor

    2013-02-21

    The appearance of post-operative cognitive dysfunction as a result of open heart surgery has been proven by several studies. Focal and/or sporadic neuron damage emerging in the central nervous system may not only appear as cognitive dysfunction, but might strongly influence features of physiological tremor. We investigated 110 patients (age: 34-73 years; 76 male, 34 female; 51 coronary artery bypass grafting (CABG), 25 valve replacement, 25 combined open heart surgery, 9 off-pump CABG) before surgery and after open-heart surgery on the 3(rd) to 5(th) post-operative day. The assessment of the physiological tremor analysis was performed with our newly developed equipment based on the Analog Devices ADXL 320 JPC integrated accelerometer chip. Recordings were stored on a PC and spectral analysis was performed by fast Fourier transformation (FFT). We compared power integrals in the 1-4 Hz, 4-8 Hz and 8-12 Hz frequency ranges and these were statistically assessed by the Wilcoxon rank correlation test. We found significant changes in the power spectrum of physiological tremor. The spectrum in the 8-12 Hz range (neuronal oscillation) decreased and a shift was recognised to the lower spectrum (p < 0.01). The magnitude of the shift was not significantly higher for females than for males (p < 0.157). We found no significant difference between the shift and the cross-clamp or perfusion time (p < 0.6450). The assessment of physiological tremor by means of our novel, feasible method may provide a deeper insight into the mechanism of central nervous system damage associated with open heart surgery.

  17. The decrease in the population of Gluconacetobacter diazotrophicus in sugarcane after nitrogen fertilization is related to plant physiology in split root experiments.

    Science.gov (United States)

    Rodríguez-Andrade, Osvaldo; Fuentes-Ramírez, Luis E; Morales-García, Yolanda E; Molina-Romero, Dalia; Bustillos-Cristales, María R; Martínez-Contreras, Rebeca D; Muñoz-Rojas, Jesús

    2015-01-01

    It has been established that a decrease in the population of Gluconacetobacter diazotrophicus associated with sugarcane occurs after nitrogen fertilization. This fact could be due to a direct influence of NH(4)NO(3) on bacterial cells or to changes in plant physiology after fertilizer addition, affecting bacterial establishment. In this work, we observed that survival of G. diazotrophicus was directly influenced when 44.8mM of NH(4)NO(3) (640mgN/plant) was used for in vitro experiments. Furthermore, micropropagated sugarcane plantlets were inoculated with G. diazotrophicus and used for split root experiments, in which both ends of the system were fertilized with a basal level of NH(4)NO(3) (0.35mM; 10mgN/plant). Twenty days post inoculation (dpi) one half of the plants were fertilized with a high dose of NH(4)NO(3) (6.3mM; 180 mgN/plant) on one end of the system. This nitrogen level was lower than that directly affecting G. diazotrophicus cells; however, it caused a decrease in the bacterial population in comparison with control plants fertilized with basal nitrogen levels. The decrease in the population of G. diazotrophicus was higher in pots fertilized with a basal nitrogen level when compared with the corresponding end supplied with high levels of NH4NO3 (100dpi; 80 days post fertilization) of the same plant system. These observations suggest that the high nitrogen level added to the plants induce systemic physiological changes that affect the establishment of G. diazotrophicus.

  18. Wetland Plant Physiology Exhibits Controls on Carbon Sequestration Processes in a Restored Temperate Peatland of California, USA

    Science.gov (United States)

    Windham-Myers, L.; Byrd, K. B.; Khanna, S.; Miller, R.; Anderson, F.

    2011-12-01

    Wetland soils, especially peatlands, serve as the leading long-term sink of carbon (C) in the terrestrial biosphere, representing ~5% of global terrestrial ecosystem acreage but ~25% of total stored terrestrial organic C. While inhibition of microbial respiration rates is a necessary component of peat formation, plant processes regulate gross and net organic matter production (GPP and NPP) and microbial respiration in the rhizosphere. Recent work in a 14-year-old, 6-ha experimental wetland complex in the California's Sacramento-San Joaquin Delta has documented that continuous flooding at 25 cm depth can generate peat growth averaging 1 kg C m-2 y-1, and elevation gains approaching 4 cm y-1, 40-fold greater than historic rates tied to mean sea level rise (1mm y-1). To determine macrophyte controls on organic matter production and respiration in emergent marsh habitats, plant physiological processes were examined for 3 dominant species: hardstem bulrush (Schoenoplectus acutus), narrowleaf and broadleaf cattail (Typha angustifolia and T. latifolia). Leaf-level photosynthetic rates (GPP) were collected monthly with a LiCor 6400XT in May-September of 2010 and 2011 across a gradient of water residence time. GPP, stomatal conductance, photosynthetically active radiation (PAR), relative humidity and leaf temperatures were assessed from pre-dawn to solar-noon to assess light-use (LUE) and water-use efficiency (WUE) for carbon assimilation (A). CO2 levels (Ci) were regulated to generate A-Ci curves, indicating leaf capacity to assimilate recycled CO2. Porewater acetate concentrations and live root concentrations of ethanol and acetaldehyde were assayed seasonally in 2011 as relative indices of fermentative respiration. Plant species distribution, NPP and leaf-area indices (LAI) were calculated using allometric relationships, and used to scale-up leaf-level GPP estimates, as well as to ground-truth high-resolution CIR imagery, to compare NDVIs with recent hyperspectral data

  19. Carbonic Anhydrase and Zinc in Plant Physiology Anhidrasa Carbónica y Zinc en Fisiología Vegetal

    Directory of Open Access Journals (Sweden)

    Dalila Jacqueline Escudero-Almanza

    2012-03-01

    Full Text Available Carbonic anhydrase (CA (EC: 2.4.1.1 catalyzes the rapid conversion of carbon dioxide plus water into a proton and the bicarbonate ion (HCO3- that can be found in prokaryotes and higher organisms; it is represented by four different families. Carbonic anhydrase is a metalloenzyme that requires Zn as a cofactor and is involved in diverse biological processes including pH regulation, CO2 transfer, ionic exchange, respiration, CO2 photosynthetic fixation, and stomatal closure. Therefore, the review includes relevant aspects about CA morphology, oligomerization, and structural differences in the active site. On the other hand, we consider the general characteristics of Zn, its geometry, reactions, and physiology. We then consider the CA catalysis mechanism that is carried out by the metal ion and where Zn acts as a cofactor. Zinc deficiency can inhibit growth and protein synthesis, and there is evidence that it reduces the CA content in some plants, which is a relationship addressed in this review. In leaves, CA represents 20.1% of total soluble protein, while it is the second most abundant in the chloroplast after ribulose 1,5-disphosphate carboxylase/oxygenase (RuBisCO. This facilitates the supply of CO2 to the phosphoenolpyruvate carboxylase in C4 and CAM plants and RuBisCO in C3 plants.La anhidrasa carbónica (CA (EC: 4.2.1.1 cataliza la conversión rápida de dióxido de carbono más agua en un protón y el ion bicarbonato (HCO3-; la cual puede encontrarse en procariotas y en organismos superiores y está representada por cuatro familias distintas. La CA es una metaloenzima que requiere Zn como cofactor y está implicada en diversos procesos biológicos, incluyendo la regulación del pH, la transferencia de CO2, intercambio iónico, la respiración, la fijación fotosintética de CO2, y el cierre estomático. Por lo cual, la revisión incluye aspectos relevantes sobre la morfología de laAC, su oligomerización y diferencias estructurales en el

  20. Exergy analysis of a MSF distillation plant

    Energy Technology Data Exchange (ETDEWEB)

    Kahraman, Nafiz [Department of Mechanical Engineering, Erciyes University, Kayseri (Turkey)]. E-mail: nafiz@erciyes.edu.tr; Cengel, Yunus A. [Department of Mechanical Engineering/312, University of Nevada, Reno, NV 89557 (United States)

    2005-09-15

    In this paper, a large MSF distillation plant in the gulf area is analyzed thermodynamically using actual plant operation data. Exergy flow rates are evaluated throughout the plant, and the exergy flow diagram is prepared. The rates of exergy destruction and their percentages are indicated on the diagram so that the locations of highest exergy destruction can easily be identified. The highest exergy destruction (77.7%) occurs within the MSF unit, as expected, and this can be reduced by increasing the number of flashing stages. The exergy destruction in the pumps and motors account for 5.3% of the total, and this also can be reduced by using high efficiency motors and pumps. The plant is determined to have a second law efficiency of just 4.2%, which is very low. This indicates that there are major opportunities in the plant to reduce exergy destruction and, thus, the amount of electric and thermal energy supplied, making the operation of the plant more cost effective.

  1. 76 FR 66033 - Plants for Planting Whose Importation Is Not Authorized Pending Pest Risk Analysis; Notice of...

    Science.gov (United States)

    2011-10-25

    ... Pending Pest Risk Analysis; Notice of Availability of Data Sheets for Taxa of Plants for Planting That Are Quarantine Pests or Hosts of Quarantine Pests AGENCY: Animal and Plant Health Inspection Service, USDA... pests and 107 taxa of plants for planting are hosts of 13 quarantine pests and therefore should be...

  2. 78 FR 41908 - Plants for Planting Whose Importation Is Not Authorized Pending Pest Risk Analysis; Notice of...

    Science.gov (United States)

    2013-07-12

    ... Not Authorized Pending Pest Risk Analysis; Notice of Availability of Data Sheets for Taxa of Plants for Planting That Are Quarantine Pests or Hosts of Quarantine Pests AGENCY: Animal and Plant Health... plants for planting are quarantine pests or hosts of quarantine pests and, therefore, should be added...

  3. Morphological, physiological and anatomical traits of plant functional types in temperate grasslands along a large-scale aridity gradient in northeastern China.

    Science.gov (United States)

    Guo, Chengyuan; Ma, Linna; Yuan, Shan; Wang, Renzhong

    2017-01-20

    At the species level, plants can respond to climate changes by changing their leaf traits; however, there is scant information regarding the responses of morphological, physiological and anatomical traits of plant functional types (PFTs) to aridity. Herein, the leaf traits of five PFTs representing 17 plant species in temperate grasslands were examined along a large-scale aridity gradient in northeastern China. The results show that leaf thickness in shrubs, perennial grasses and forbs increased with heightened aridity. Trees increased soluble sugar content, but shrubs, perennials and annual grasses enhanced proline accumulation due to increasing aridity. Moreover, vessel diameter and stomatal index in shrubs and perennial grasses decreased with increasing aridity, but stomatal density and vascular diameter of five PFTs were not correlated with water availability. In conclusion, divergences in adaptive strategies to aridity among these PFTs in temperate grasslands were likely caused by differences in their utilization of water resources, which have different temporal and spatial distribution patterns. Leaf traits of shrubs and perennial grasses had the largest responses to variability of aridity through regulation of morphological, physiological and anatomical traits, which was followed by perennial forbs. Trees and annual grasses endured aridity only by adjusting leaf physiological processes.

  4. Morphological, physiological and anatomical traits of plant functional types in temperate grasslands along a large-scale aridity gradient in northeastern China

    Science.gov (United States)

    Guo, Chengyuan; Ma, Linna; Yuan, Shan; Wang, Renzhong

    2017-01-01

    At the species level, plants can respond to climate changes by changing their leaf traits; however, there is scant information regarding the responses of morphological, physiological and anatomical traits of plant functional types (PFTs) to aridity. Herein, the leaf traits of five PFTs representing 17 plant species in temperate grasslands were examined along a large-scale aridity gradient in northeastern China. The results show that leaf thickness in shrubs, perennial grasses and forbs increased with heightened aridity. Trees increased soluble sugar content, but shrubs, perennials and annual grasses enhanced proline accumulation due to increasing aridity. Moreover, vessel diameter and stomatal index in shrubs and perennial grasses decreased with increasing aridity, but stomatal density and vascular diameter of five PFTs were not correlated with water availability. In conclusion, divergences in adaptive strategies to aridity among these PFTs in temperate grasslands were likely caused by differences in their utilization of water resources, which have different temporal and spatial distribution patterns. Leaf traits of shrubs and perennial grasses had the largest responses to variability of aridity through regulation of morphological, physiological and anatomical traits, which was followed by perennial forbs. Trees and annual grasses endured aridity only by adjusting leaf physiological processes. PMID:28106080

  5. QTL analysis of leaf photosynthesis rate and related physiological traits in Brassica napus

    Institute of Scientific and Technical Information of China (English)

    YAN Xing-ying; QU Cun-min; LI Jia-na; CHEN Li; LIU Lie-zhao

    2015-01-01

    Rapeseed (Brassica napus L.) oil is the crucial source of edible oil in China. In addition, it can become a major renewable and sustainable feedstock for biodiesel production in the future. It is known that photosynthesis products are the primary sources for dry matter accumulation in rapeseed. Therefore, increasing the photosynthetic efifciency is desirable for the raise of rapeseed yield. The objective of the present study was to identify the genetic mechanism of photosynthesis based on the description of relationships between different photosynthetic traits and their quantitative trait loci (QTL) by using a recombinant inbred line (RIL) population with 172 lines. Speciifcal y, correlation analysis in this study showed that internal CO2 concentration has negative correlations with other three physiological traits under two different stages. Total y, 11 and 12 QTLs of the four physiological traits measured at the stages 1 and 2 were detected by using a high-density single nu-cleotidepolymorphism (SNP) markers linkage map with composite interval mapping (CIM), respectively. Three co-localized QTLs on A03 were detected at stage 1 with 5, 5, and 10%of the phenotypic variation, respectively. Other two co-localized QTLs were located on A05 at stage 2, which explained up to 12 and 5%of the phenotypic variation, respectively. The results are beneifcial for our understanding of genetic control of photosynthetic physiological characterizations and improvement of rapeseed yield in the future.

  6. Latent physiological factors of complex human diseases revealed by independent component analysis of clinarrays

    Directory of Open Access Journals (Sweden)

    Chen David P

    2010-10-01

    Full Text Available Abstract Background Diagnosis and treatment of patients in the clinical setting is often driven by known symptomatic factors that distinguish one particular condition from another. Treatment based on noticeable symptoms, however, is limited to the types of clinical biomarkers collected, and is prone to overlooking dysfunctions in physiological factors not easily evident to medical practitioners. We used a vector-based representation of patient clinical biomarkers, or clinarrays, to search for latent physiological factors that underlie human diseases directly from clinical laboratory data. Knowledge of these factors could be used to improve assessment of disease severity and help to refine strategies for diagnosis and monitoring disease progression. Results Applying Independent Component Analysis on clinarrays built from patient laboratory measurements revealed both known and novel concomitant physiological factors for asthma, types 1 and 2 diabetes, cystic fibrosis, and Duchenne muscular dystrophy. Serum sodium was found to be the most significant factor for both type 1 and type 2 diabetes, and was also significant in asthma. TSH3, a measure of thyroid function, and blood urea nitrogen, indicative of kidney function, were factors unique to type 1 diabetes respective to type 2 diabetes. Platelet count was significant across all the diseases analyzed. Conclusions The results demonstrate that large-scale analyses of clinical biomarkers using unsupervised methods can offer novel insights into the pathophysiological basis of human disease, and suggest novel clinical utility of established laboratory measurements.

  7. Application of meta-transcriptomics and -proteomics to analysis of in situ physiological state

    Energy Technology Data Exchange (ETDEWEB)

    Konopka, Allan; Wilkins, Michael J.

    2012-05-18

    Analysis of the growth-limiting factor or environmental stressors affecting microbes in situ is of fundamental importance but analytically difficult. Microbes can reduce in situ limiting nutrient concentrations to sub-micromolar levels, and contaminated ecosystems may contain multiple stressors. The patterns of gene or protein expression by microbes in nature can be used to infer growth limitations, because they are regulated in response to environmental conditions. Experimental studies under controlled conditions in the laboratory provide the physiological underpinnings for developing these physiological indicators. Although regulatory networks may differ among specific microbes, there are some broad principles that can be applied, related to limiting nutrient acquisition, resource allocation, and stress responses. As technologies for transcriptomics and proteomics mature, the capacity to apply these approaches to complex microbial communities will accelerate. Global proteomics has the particular advantage that it reflects expressed catalytic activities. Furthermore, the high mass accuracy of some proteomic approaches allows mapping back to specific microbial strains. For example, at the Rifle IFRC field site in Western Colorado, the physiological status of Fe(III)-reducing populations has been tracked over time. Members of a 'subsurface clade' within the Geobacter predominated during carbon amendment to the subsurface environment. At the functional level, proteomic identifications produced inferences regarding (i) temporal changes in anabolism and catabolism of acetate, (ii) the onset of N2 fixation when N became limiting, and (iii) expression of phosphate transporters during periods of intense growth. The application of these approaches in situ can lead to discovery of novel physiological adaptations.

  8. An analysis of the physiological FDG uptake in the stomach with the water gastric distention method

    Energy Technology Data Exchange (ETDEWEB)

    Kamimura, Kiyohisa [Fujimoto Hayasuzu Hospital, Department of Radiology, Miyazaki (Japan); Kagoshima University Graduate School of Medical and Dental Sciences, Department of Radiology, Kagoshima (Japan); Fujita, Seigo; Yano, Tatsuhiko; Ogita, Mikio; Umemura, Yoshiro; Fujimoto, Toshiro [Fujimoto Hayasuzu Hospital, Department of Radiology, Miyazaki (Japan); Nishii, Ryuichi; Wakamatsu, Hideyuki; Nagamachi, Shigeki [Miyazaki Medical College, Department of Radiology, Miyazaki (Japan); Nakajo, Masayuki [Kagoshima University Graduate School of Medical and Dental Sciences, Department of Radiology, Kagoshima (Japan)

    2007-11-15

    Physiological FDG uptake in the stomach is a common phenomenon, especially noted at the cardia. Water intake just before scanning will result in gastric distention and thinning of the gastric wall, which in turn may lead to a reduction in the physiological uptake in the gastric wall. In the current study, we investigated whether gastric distention by water intake just before PET imaging reduces physiological FDG uptake in the stomach. The patient population comprised 60 patients who underwent whole-body FDG-PET imaging for cancer screening following gastroscopy performed within the preceding week. All patients took 400 ml of water for hydration and were administered 185 MBq of FDG intravenously. The patients were randomly divided into two groups: a group with additional water intake (AW group; n = 30) and a group without additional water intake (NW group; n = 30). In the AW group, an additional 400 ml of water was given just before PET imaging. For quantitative analysis, the stomach was classified into three areas [upper (U), middle (M) and lower (L)], and the degree of FDG uptake in each area was evaluated using standardised uptake values (SUVs). In the NW group, the mean SUVs in the U, M and L areas were 2.41 {+-} 0.75, 2.28 {+-} 0.73 and 1.61 {+-} 0.89, respectively, while in the AW group they were 1.82 {+-} 0.66, 1.73 {+-} 0.56 and 1.48 {+-} 0.49, respectively, and 2.21 {+-} 0.38 in the oesophago-gastric junction. The mean SUVs in the U and M areas in the AW group were significantly lower than those in the NW group (p < 0.05). Additional water intake just before PET imaging is an effective method for suppressing physiological FDG uptake in the stomach. (orig.)

  9. Large scale physiological readjustment during growth enables rapid, comprehensive and inexpensive systems analysis

    Directory of Open Access Journals (Sweden)

    Larsen David J

    2010-05-01

    Full Text Available Abstract Background Rapidly characterizing the operational interrelationships among all genes in a given organism is a critical bottleneck to significantly advancing our understanding of thousands of newly sequenced microbial and eukaryotic species. While evolving technologies for global profiling of transcripts, proteins, and metabolites are making it possible to comprehensively survey cellular physiology in newly sequenced organisms, these experimental techniques have not kept pace with sequencing efforts. Compounding these technological challenges is the fact that individual experiments typically only stimulate relatively small-scale cellular responses, thus requiring numerous expensive experiments to survey the operational relationships among nearly all genetic elements. Therefore, a relatively quick and inexpensive strategy for observing changes in large fractions of the genetic elements is highly desirable. Results We have discovered in the model organism Halobacterium salinarum NRC-1 that batch culturing in complex medium stimulates meaningful changes in the expression of approximately two thirds of all genes. While the majority of these changes occur during transition from rapid exponential growth to the stationary phase, several transient physiological states were detected beyond what has been previously observed. In sum, integrated analysis of transcript and metabolite changes has helped uncover growth phase-associated physiologies, operational interrelationships among two thirds of all genes, specialized functions for gene family members, waves of transcription factor activities, and growth phase associated cell morphology control. Conclusions Simple laboratory culturing in complex medium can be enormously informative regarding the activities of and interrelationships among a large fraction of all genes in an organism. This also yields important baseline physiological context for designing specific perturbation experiments at

  10. [Molecular, genetic and physiological analysis of photoinhibition and photosynthetic]. Progress report, June 1991--November 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-01

    A major goal of this project is to use a combined molecular genetic, biochemical and physiological approach to understand the relationship between photosynthetic performance and the structure of the multifunctional D1 reaction center protein of Photosystem II encoded by the chloroplast psbA gene. Relative to other chloroplast proteins, turover of D1 is rapid and highly light dependent and de novo synthesis of D1 is required for a plant`s recovery from short term exposure to irradiances which induce photoinhibitory damage. These observations have led to models for a damage/repair cycle of PSII involving the targeted degradation and replacement of photodamaged D1. To investigate the effects of perturbing the D1 cycle on photosynthesis and autotrophic growth under high and low irradiance, we have examined the consequences of site-specific mutations of the psbA and 16S rRNA genes affecting synthesis, maturation and function/stability of the D1 protein introduced into the chloroplast genome of wildtype strain of the green alga Chlamydomonas reinhardtii using biolistic transformation.

  11. Physiological Characterization and Comparative Transcriptome Analysis of White and Green Leaves of Ananas comosus var. bracteatus.

    Science.gov (United States)

    Li, Xia; Kanakala, Surapathrudu; He, Yehua; Zhong, Xiaolan; Yu, Sanmiao; Li, Ruixue; Sun, Lingxia; Ma, Jun

    2017-01-01

    Leaf coloration is one of the most important and attractive characteristics of Ananas comosus var. bracteatus. The chimeric character is not stable during the in vitro tissue culturing. Many regenerated plants lost economic values for the loss of the chimeric character of leaves. In order to reveal the molecular mechanisms involved in the albino phenotype of the leaf cells, the physiological and transcriptional differences between complete white (CWh) and green (CGr) leaf cells of A. comosus var. bracteatus were analyzed. A total of 1,431 differentially expressed unigenes (DEGs) in CGr and CWh leaves were identified using RNA-seq. A comparison to the COG, GO and KEGG annotations revealed DEGs involved in chlorophyll biosynthesis, chloroplast development and photosynthesis. Furthermore, the measurement of main precursors of chlorophyll in the CWh leaves confirmed that the rate-limiting step in chlorophyll biosynthesis, and thus the cause of the albino phenotype of the white cells, was the conversion of pyrrole porphobilinogen (PBG) to uroporphyrinogen III (Uro III). The enzyme activity of porphobilinogen deaminase (PBGD) and uroporporphyrinogn III synthase (UROS), which catalyze the transition of PBG to Uro III, was significantly decreased in the CWh leaves. Our data showed the transcriptional differences between the CWh and CGr plants and characterized key steps in chlorophyll biosynthesis of the CWh leaves. These results contribute to our understanding of the mechanisms and regulation of pigment biosynthesis in the CWh leaf cells of A. comosus var. bracteatus.

  12. Benefits for Plants in Ant-Plant Protective Mutualisms: A Meta-Analysis

    Science.gov (United States)

    Trager, Matthew D.; Bhotika, Smriti; Hostetler, Jeffrey A.; Andrade, Gilda V.; Rodriguez-Cabal, Mariano A.; McKeon, C. Seabird; Osenberg, Craig W.; Bolker, Benjamin M.

    2010-01-01

    Costs and benefits for partners in mutualistic interactions can vary greatly, but surprisingly little is known about the factors that drive this variation across systems. We conducted a meta-analysis of ant-plant protective mutualisms to quantify the effects of ant defenders on plant reproductive output, to evaluate if reproductive effects were predicted from reductions in herbivory and to identify characteristics of the plants, ants and environment that explained variation in ant protection. We also compared our approach with two other recent meta-analyses on ant-plant mutualisms, emphasizing differences in our methodology (using a weighted linear mixed effects model) and our focus on plant reproduction rather than herbivore damage. Based on 59 ant and plant species pairs, ant presence increased plant reproductive output by 49% and reduced herbivory by 62%. The effects on herbivory and reproduction within systems were positively correlated, but the slope of this relationship (0.75) indicated that tolerance to foliar herbivory may be a common plant response to absence of ant guards. Furthermore, the relationship between foliar damage and reproduction varied substantially among systems, suggesting that herbivore damage is not a reliable surrogate for fitness consequences of ant protection. Studies that experimentally excluded ants reported a smaller effect of ant protection on plant reproduction than studies that relied upon natural variation in ant presence, suggesting that study methods can affect results in these systems. Of the ecological variables included in our analysis, only plant life history (i.e., annual or perennial) explained variation in the protective benefit of mutualistic ants: presence of ants benefitted reproduction of perennials significantly more than that of annuals. These results contrast with other quantitative reviews of these relationships that did not include plant life history as an explanatory factor and raise several questions to guide

  13. Benefits for plants in ant-plant protective mutualisms: a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Matthew D Trager

    Full Text Available Costs and benefits for partners in mutualistic interactions can vary greatly, but surprisingly little is known about the factors that drive this variation across systems. We conducted a meta-analysis of ant-plant protective mutualisms to quantify the effects of ant defenders on plant reproductive output, to evaluate if reproductive effects were predicted from reductions in herbivory and to identify characteristics of the plants, ants and environment that explained variation in ant protection. We also compared our approach with two other recent meta-analyses on ant-plant mutualisms, emphasizing differences in our methodology (using a weighted linear mixed effects model and our focus on plant reproduction rather than herbivore damage. Based on 59 ant and plant species pairs, ant presence increased plant reproductive output by 49% and reduced herbivory by 62%. The effects on herbivory and reproduction within systems were positively correlated, but the slope of this relationship (0.75 indicated that tolerance to foliar herbivory may be a common plant response to absence of ant guards. Furthermore, the relationship between foliar damage and reproduction varied substantially among systems, suggesting that herbivore damage is not a reliable surrogate for fitness consequences of ant protection. Studies that experimentally excluded ants reported a smaller effect of ant protection on plant reproduction than studies that relied upon natural variation in ant presence, suggesting that study methods can affect results in these systems. Of the ecological variables included in our analysis, only plant life history (i.e., annual or perennial explained variation in the protective benefit of mutualistic ants: presence of ants benefitted reproduction of perennials significantly more than that of annuals. These results contrast with other quantitative reviews of these relationships that did not include plant life history as an explanatory factor and raise several

  14. Nuclear Power Plant Module, NPP-1: Nuclear Power Cost Analysis.

    Science.gov (United States)

    Whitelaw, Robert L.

    The purpose of the Nuclear Power Plant Modules, NPP-1, is to determine the total cost of electricity from a nuclear power plant in terms of all the components contributing to cost. The plan of analysis is in five parts: (1) general formulation of the cost equation; (2) capital cost and fixed charges thereon; (3) operational cost for labor,…

  15. Nonlethal evaluation of the physiological health of unionid mussels: Method for biopsy and glycogen analysis

    Science.gov (United States)

    Naimo, T.J.; Damschen, E.D.; Rada, R.G.; Monroe, E.M.

    1998-01-01

    In long-lived unionid mussels, many short-term measures of growth are of limited value. Changes in physiological condition may be an early indication of stress, because the increased energy demand associated with stress often results in a depletion of glycogen reserves, the principal storage form of carbohydrates in unionid mussels. Our goal was to nonlethally extract tissue from freshwater mussels and then to develop a rapid and dependable method for the analysis of glycogen in the tissue extracts. A biopsy technique was developed to remove between 5 and 10 mg of food tissue in Amblema plicata plicata. The survival rate did not differ between biopsied and non-biopsied mussels during a 581-d observation period, demonstrating that the biopsy technique will allow nonlethal evaluation of the physiological condition of individual mussels through measurement of changes in contaminant, genetic, and biochemical indicators in tissue. We also modified the standard alkaline digestion and phenol-sulfuric acid analysis of glycogen for use on the small samples of biopsied tissue and to reduce analysis time and cost. We present quality control data, including method detection limits and estimates of precision and bias. The modified analytical method is rapid and accurate and has a method detection limit of 0.014 mg glycogen. Glycogen content in the biopsied samples was well above the method detection limit; it ranged from 0.09 to 0.36 mg, indicating that the method should be applicable to native mussels.

  16. Physiological evaluation of the filamentous fungus Trichoderma reesei in production processes by marker gene expression analysis

    Directory of Open Access Journals (Sweden)

    Penttilä Merja

    2007-05-01

    Full Text Available Abstract Background Biologically relevant molecular markers can be used in evaluation of the physiological state of an organism in biotechnical processes. We monitored at high frequency the expression of 34 marker genes in batch, fed-batch and continuous cultures of the filamentous fungus Trichoderma reesei by the transcriptional analysis method TRAC (TRanscript analysis with the aid of Affinity Capture. Expression of specific genes was normalised either with respect to biomass or to overall polyA RNA concentration. Expressional variation of the genes involved in various process relevant cellular functions, such as protein production, growth and stress responses, was related to process parameters such as specific growth and production rates and substrate and dissolved oxygen concentrations. Results Gene expression of secreted cellulases and recombinant Melanocarpus albomyces laccase predicted the trends in the corresponding extracellular enzyme production rates and was highest in a narrow "physiological window" in the specific growth rate (μ range of 0.03 – 0.05 h-1. Expression of ribosomal protein mRNAs was consistent with the changes in μ. Nine starvation-related genes were found as potential markers for detection of insufficient substrate feed for maintaining optimal protein production. For two genes induced in anaerobic conditions, increasing transcript levels were measured as dissolved oxygen decreased. Conclusion The data obtained by TRAC supported the usefulness of focused and intensive transcriptional analysis in monitoring of biotechnical processes providing thus tools for process optimisation purposes.

  17. Physiological response of riparian plants to watering in hyper-arid areas of Tarim River,China

    Institute of Scientific and Technical Information of China (English)

    RUAN Xiao; WANG Qiang; CHEN Yaning; LI Weihong

    2007-01-01

    The physiological responses and adaptive strategies of Populus euphratica Oliv.(arbor species),Tamarix ramosissima Ldb.(bush species),and Apocynum venetum L.(herb species)to variations in water and salinity stress were studied in the hyper-arid environment of the Tarim River in China.The groundwater table,the saline content of the groundwater,as well as the content of free proline,soluble sugars,plant endogenous hormones (abscisic acid (ABA),and cytokinins (CTK))of the leaves of the three species were monitored and analyzed at the lower reaches of the Tarim River in the study area where five transects were fixed at 100 m intervals along a vertical sampling line before and after water release.Saline stress dramatically increased soluble sugar concentration of the three species.Differences in sugar accumulation were determined among the species at different transects.The free proline concentration of the leaves of T.ramosissima and P.euphratica showed a proportional decrease with various degrees of elevation of the groundwater table after water release.There was a least correlation between the soluble sugars and proline stimulation in T.ramosissima.It was strongly suggested that T.ramosissima developed a different strategy to accumulate organic solutes to adapt to the stress environment.The soluble sugars and proline accumulation responded to the changes of groundwater table independently:the former occurred under salt stress,whereas the latter was more significant under drought stress.The concentration and the increase in concentration of ABA and CTK involved in stress resistance of the three species were also determined.This increase in the hormone concentration in P.euphratica was different from that of the other two species.Expressed as a function of increase of ABA concentration in leaves,A.venetum and T.ramosissima showed a different solute accumulation in response to groundwater table.There was a significant correlation between ABA accumulation and A [proline

  18. Medicago truncatula root nodule proteome analysis reveals differential plant and bacteroid responses to drought stress.

    Science.gov (United States)

    Larrainzar, Estíbaliz; Wienkoop, Stefanie; Weckwerth, Wolfram; Ladrera, Rubén; Arrese-Igor, Cesar; González, Esther M

    2007-07-01

    Drought is one of the environmental factors most affecting crop production. Under drought, symbiotic nitrogen fixation is one of the physiological processes to first show stress responses in nodulated legumes. This inhibition process involves a number of factors whose interactions are not yet understood. This work aims to further understand changes occurring in nodules under drought stress from a proteomic perspective. Drought was imposed on Medicago truncatula 'Jemalong A17' plants grown in symbiosis with Sinorhizobium meliloti strain 2011. Changes at the protein level were analyzed using a nongel approach based on liquid chromatography coupled to tandem mass spectrometry. Due to the complexity of nodule tissue, the separation of plant and bacteroid fractions in M. truncatula root nodules was first checked with the aim of minimizing cross contamination between the fractions. Second, the protein plant fraction of M. truncatula nodules was profiled, leading to the identification of 377 plant proteins, the largest description of the plant nodule proteome so far. Third, both symbiotic partners were independently analyzed for quantitative differences at the protein level during drought stress. Multivariate data mining allowed for the classification of proteins sets that were involved in drought stress responses. The isolation of the nodule plant and bacteroid protein fractions enabled the independent analysis of the response of both counterparts, gaining further understanding of how each symbiotic member is distinctly affected at the protein level under a water-deficit situation.

  19. Cyclic electron flow around photosystem I via chloroplast NAD(P)H dehydrogenase (NDH) complex performs a significant physiological role during photosynthesis and plant growth at low temperature in rice.

    Science.gov (United States)

    Yamori, Wataru; Sakata, Naoki; Suzuki, Yuji; Shikanai, Toshiharu; Makino, Amane

    2011-12-01

    The role of NAD(P)H dehydrogenase (NDH)-dependent cyclic electron flow around photosystem I in photosynthetic regulation and plant growth at several temperatures was examined in rice (Oryza sativa) that is defective in CHLORORESPIRATORY REDUCTION 6 (CRR6), which is required for accumulation of sub-complex A of the chloroplast NDH complex (crr6). NdhK was not detected by Western blot analysis in crr6 mutants, resulting in lack of a transient post-illumination increase in chlorophyll fluorescence, and confirming that crr6 mutants lack NDH activity. When plants were grown at 28 or 35°C, all examined photosynthetic parameters, including the CO(2) assimilation rate and the electron transport rate around photosystems I and II, at each growth temperature at light intensities above growth light (i.e. 800 μmol photons m(-2) sec(-1)), were similar between crr6 mutants and control plants. However, when plants were grown at 20°C, all the examined photosynthetic parameters were significantly lower in crr6 mutants than control plants, and this effect on photosynthesis caused a corresponding reduction in plant biomass. The F(v)/F(m) ratio was only slightly lower in crr6 mutants than in control plants after short-term strong light treatment at 20°C. However, after long-term acclimation to the low temperature, impairment of cyclic electron flow suppressed non-photochemical quenching and promoted reduction of the plastoquinone pool in crr6 mutants. Taken together, our experiments show that NDH-dependent cyclic electron flow plays a significant physiological role in rice during photosynthesis and plant growth at low temperature.

  20. Mindfulness mediates the physiological markers of stress: Systematic review and meta-analysis.

    Science.gov (United States)

    Pascoe, Michaela C; Thompson, David R; Jenkins, Zoe M; Ski, Chantal F

    2017-08-23

    Meditation is a popular form of stress management, argued to mediate stress reactivity. However, many studies in this field commonly fail to include an active control group. Given the frequency with which people are selecting meditation as a form of self-management, it is important to validate if the practice is effective in mediating stress-reactivity using well-controlled studies. Thus, we aimed to conduct a meta-analysis investigating the neurobiological effects of meditation, including focused attention, open monitoring and automatic self-transcending subtypes, compared to an active control, on markers of stress. In the current meta-analysis and systematic review, we included randomised controlled trials comparing meditation interventions compared to an active control on physiological markers of stress. Studied outcomes include cortisol, blood pressure, heart-rate, lipids and peripheral cytokine expression. Forty-five studies were included. All meditation subtypes reduced systolic blood pressure. Focused attention meditations also reduced cortisol and open monitoring meditations also reduced heart rate. When all meditation forms were analysed together, meditation reduced cortisol, C - reactive protein, blood pressure, heart rate, triglycerides and tumour necrosis factor-alpha. Overall, meditation practice leads to decreased physiological markers of stress in a range of populations. Copyright © 2017. Published by Elsevier Ltd.

  1. LISSAT Analysis of a Generic Centrifuge Enrichment Plant

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, H; Elayat, H A; O?Connell, W J; Szytel, L; Dreicer, M

    2007-05-31

    The U.S. Department of Energy (DOE) is interested in developing tools and methods for use in designing and evaluating safeguards systems for current and future plants in the nuclear power fuel cycle. The DOE is engaging several DOE National Laboratories in efforts applied to safeguards for chemical conversion plants and gaseous centrifuge enrichment plants. As part of the development, Lawrence Livermore National Laboratory has developed an integrated safeguards system analysis tool (LISSAT). This tool provides modeling and analysis of facility and safeguards operations, generation of diversion paths, and evaluation of safeguards system effectiveness. The constituent elements of diversion scenarios, including material extraction and concealment measures, are structured using directed graphs (digraphs) and fault trees. Statistical analysis evaluates the effectiveness of measurement verification plans and randomly timed inspections. Time domain simulations analyze significant scenarios, especially those involving alternate time ordering of events or issues of timeliness. Such simulations can provide additional information to the fault tree analysis and can help identify the range of normal operations and, by extension, identify additional plant operational signatures of diversions. LISSAT analyses can be used to compare the diversion-detection probabilities for individual safeguards technologies and to inform overall strategy implementations for present and future plants. Additionally, LISSAT can be the basis for a rigorous cost-effectiveness analysis of safeguards and design options. This paper will describe the results of a LISSAT analysis of a generic centrifuge enrichment plant. The paper will describe the diversion scenarios analyzed and the effectiveness of various safeguards systems alternatives.

  2. [Construction and analysis of a monitoring system with remote real-time multiple physiological parameters based on cloud computing].

    Science.gov (United States)

    Zhu, Lingyun; Li, Lianjie; Meng, Chunyan

    2014-12-01

    There have been problems in the existing multiple physiological parameter real-time monitoring system, such as insufficient server capacity for physiological data storage and analysis so that data consistency can not be guaranteed, poor performance in real-time, and other issues caused by the growing scale of data. We therefore pro posed a new solution which was with multiple physiological parameters and could calculate clustered background data storage and processing based on cloud computing. Through our studies, a batch processing for longitudinal analysis of patients' historical data was introduced. The process included the resource virtualization of IaaS layer for cloud platform, the construction of real-time computing platform of PaaS layer, the reception and analysis of data stream of SaaS layer, and the bottleneck problem of multi-parameter data transmission, etc. The results were to achieve in real-time physiological information transmission, storage and analysis of a large amount of data. The simulation test results showed that the remote multiple physiological parameter monitoring system based on cloud platform had obvious advantages in processing time and load balancing over the traditional server model. This architecture solved the problems including long turnaround time, poor performance of real-time analysis, lack of extensibility and other issues, which exist in the traditional remote medical services. Technical support was provided in order to facilitate a "wearable wireless sensor plus mobile wireless transmission plus cloud computing service" mode moving towards home health monitoring for multiple physiological parameter wireless monitoring.

  3. Techniques for Analysis of Plant Phenolic Compounds

    OpenAIRE

    Roberts, Thomas H.; Meredith A. Wilkes; Ali Khoddami

    2013-01-01

    Phenolic compounds are well-known phytochemicals found in all plants. They consist of simple phenols, benzoic and cinnamic acid, coumarins, tannins, lignins, lignans and flavonoids. Substantial developments in research focused on the extraction, identification and quantification of phenolic compounds as medicinal and/or dietary molecules have occurred over the last 25 years. Organic solvent extraction is the main method used to extract phenolics. Chemical procedures are used to detect the pre...

  4. A meta-analysis of local adaptation in plants.

    Directory of Open Access Journals (Sweden)

    Roosa Leimu

    Full Text Available Local adaptation is of fundamental importance in evolutionary, population, conservation, and global-change biology. The generality of local adaptation in plants and whether and how it is influenced by specific species, population and habitat characteristics have, however, not been quantitatively reviewed. Therefore, we examined published data on the outcomes of reciprocal transplant experiments using two approaches. We conducted a meta-analysis to compare the performance of local and foreign plants at all transplant sites. In addition, we analysed frequencies of pairs of plant origin to examine whether local plants perform better than foreign plants at both compared transplant sites. In both approaches, we also examined the effects of population size, and of the habitat and species characteristics that are predicted to affect local adaptation. We show that, overall, local plants performed significantly better than foreign plants at their site of origin: this was found to be the case in 71.0% of the studied sites. However, local plants performed better than foreign plants at both sites of a pair-wise comparison (strict definition of local adaption only in 45.3% of the 1032 compared population pairs. Furthermore, we found local adaptation much more common for large plant populations (>1000 flowering individuals than for small populations (<1000 flowering individuals for which local adaptation was very rare. The degree of local adaptation was independent of plant life history, spatial or temporal habitat heterogeneity, and geographic scale. Our results suggest that local adaptation is less common in plant populations than generally assumed. Moreover, our findings reinforce the fundamental importance of population size for evolutionary theory. The clear role of population size for the ability to evolve local adaptation raises considerable doubt on the ability of small plant populations to cope with changing environments.

  5. Influence of ambient and enhanced ultraviolet-B radiation on the plant growth and physiological properties in two contrasting populations of Hippophae rhamnoides.

    Science.gov (United States)

    Yang, Yongqing; Yao, Yinan; He, Hai

    2008-07-01

    Two contrasting sea buckthorn (Hippophae rhamnoides L.) populations from low and high altitude regions were employed to investigate the effects of prevailing and enhanced ultraviolet-B (UV-B) radiation on plant growth and physiological properties under a UV-B-enhanced/exclusion system. The experimental design included three UV-B regimes, including excluded (-UVB), near-ambient (NA) and enhanced UV-B (+UVB) radiation. Compared with the control (-UVB), NA caused the formation of smaller but thicker plant leaves in both sea buckthorn populations, paralleled with significant increments of carotenoids and UV-absorbing compounds as well as improved water economy. NA also induced more biomass partition from shoot to root, but CO(2) assimilation rate (A), photosynthetic area and biomass accumulation were unaffected. The low-altitude population seemed sensitive to +UVB, as indicated by the decreases in total biomass, A and ascorbic acid content (Asa, an antioxidant) compared with NA. However, little +UVB effect occurred on the high-altitude population, and we suggest that the higher tolerance of this population could be associated with its specific morphological and physiological characteristics, such as small but thick leaves and high-level of Asa content, as well as its greater physiological modification in response to NA, e.g., increases in protective compounds (carotenoids and UV-absorbing compounds) and improvement in water economy, in comparison to the low-altitude population, which form an effective adaptation strategy to enhanced UV-B stress.

  6. A 7500-year record of plant physiology as palaeoenvironmental proxy from tree-ring δ13C and growth rates - the CARATE project

    Science.gov (United States)

    Arppe, L.; Helama, S.; Mielikäinen, K.; Oinonen, M.; Timonen, M.

    2012-12-01

    This contribution presents a recently launched 4-year research project, "CARATE", aiming to produce new climatic and plant physiological records at high temporal resolution by the synthesis of annually/decadally resolved tree-ring archives of growth-rates and cellulose δ13C values from high-latitude continental Europe. The project mainly relies on a supra-long pinewood chronology from Finnish Lapland covering the mid and late Holocene times continuously through the millennia since 5634 B.C. until the present-day (Eronen et al. 2002, Helama et al. 2008). The chronology provides a highly sensitive, absolutely dated proxy record of past environment and climate variability at highest possible resolution that can be calibrated directly with instrumental records of environmental variables. While growth rate records are invaluable tools for paleoclimate research at high frequencies, tree-ring δ13C compositions have the potential to portray the high-to-low-frequency climate signals per se, without complications from time-series analysis. By combining isotope and growth rate information, we aim to reconstruct regional high- and low-frequency climate variability over the past 7500 years with increased reliability, and explore the climate forcings behind the observed variations. The project was started by studying the strength of the common climatic signal both within- and between-sites, and possible associations to tree-physiological parameters. For this purpose, a set of 70 living pine trees (Pinus sylvestris) , growing in proximity of the subfossil pinewood collection sites in western and eastern Lapland, were cored for analysis of growth rates and δ13C values. α-cellulose was extracted from decadal samples corresponding to the time period 1970-2010 including both early- and latewood. The δ13C time series show a consistent response to regional environmental forcing over the entire study area, with no discernable differences between western and eastern Lapland. Within

  7. Recent developments in fast spectroscopy for plant mineral analysis

    Directory of Open Access Journals (Sweden)

    Marie evan Maarschalkerweerd

    2015-03-01

    Full Text Available Ideal fertilizer management to optimize plant productivity and quality is more relevant than ever, as global food demands increase along with the rapidly growing world population. At the same time, sub-optimal or excessive use of fertilizers leads to severe environmental damage in areas of intensive crop production. The approaches of soil and plant mineral analysis are briefly compared and discussed here, and the new techniques using fast spectroscopy that offer cheap, rapid and easy-to-use analysis of plant nutritional status are reviewed. The majority of these methods use vibrational spectroscopy, such as Visual-Near Infrared (Vis-NIR and to a lesser extent Ultraviolet (UV and Mid-Infrared (MIR spectroscopy. Advantages of and problems with application of these techniques are thoroughly discussed. Spectroscopic techniques considered having major potential for plant mineral analysis, such as chlorophyll a fluorescence, X-ray fluorescence (XRF and Laser-Induced Breakdown Spectroscopy (LIBS are also described.

  8. Predictive Physiological Anticipation Preceding Seemingly Unpredictable Stimuli:A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Julia eMossbridge

    2012-10-01

    Full Text Available This meta-analysis of 26 reports published between 1978 and 2010 tests an unusal hypothesis: for stimuli of two or more types that are presented in an order designed to be unpredictable and that produce different post-stimulus physiological activity, the direction of pre-stimulus physiological activity reflects the direction of post-stimulus physiological activity, resulting in an unexplained anticipatory effect. The reports we examined used one of two paradigms: 1 randomly presented arousing vs. neutral stimuli, or 2 guessing tasks with feedback (correct vs. incorrect. Dependent variables included: electrodermal activity, heart rate, blood volume, pupil dilation, electroencephalographic activity (EEG, and blood oxygenation level dependent (BOLD activity. To avoid including data hand-picked from multiple different analyses, no post-hoc experiments are considered. The results reveal a significant overall effect with a small effect size (random effects: overall [weighted] ES=0.21, 95%CI=0.13-0.29, z=5.3, p<5.7x10-8; fixed effects: overall ES=0.21, 95%CI=0.15-0.27, z=6.9, p<2.7x10-12. Higher quality experiments produce a quantitately larger effect size and a greater level of significance than lower quality studies. The number of contrary unpublished reports that would be necessary to reduce the level of significance to chance (p>0.05 was conservatively calculated to be 87 reports. We explore alternative explanations and examine the potential linkage between this unexplained anticipatory activity and other results demonstrating meaningful pre-stimulus activity preceding behaviourally relevant events. Multiple replications arising from different laboratories using the same methods are necessary to further examine this currently unexplained anticipatory activity. The cause of this anticipatory activity, which undoubtedly lies within the realm of natural physical processes (as opposed to supernatural or paranormal ones, remains to be determined.

  9. Transformation, evaluation of GTGene and multivariate genetic analysis for morpho-physiological and yield attributing traits in Zea mays

    Directory of Open Access Journals (Sweden)

    Aaliya Khadija

    2016-01-01

    Full Text Available Maize is the 3rd major crop grown all over the world that fulfills the needs of millions of people. Various biotic and abiotic factors caused reduction in grain yield of maize, among them weeds show most adverse effects. Objective of this study was to develop glyphosate resistance maize for developing maize hybrids and synthetic varieties with high grain and fodder yield potential. Glyphosate is a broad spectrum herbicide and resistance of crop against the herbicide, allows post emergence application, which otherwise is impossible. Higher GTG crude protein (479.94μg/g was recorded for CIL 194-975 plant. The plant CIL 194-1786 showed higher expression level of GTG protein, indicated that transformation efficiency was better for line CIL-194 than CIL-123. GTGene stably integrated to the genome of the maize lines CIL-194 and CIL-123, these transformed lines showed more ability to cope with herbicides as compared with non-transformed lines in greenhouse and field trials. The transgenic lines were sown in field and data was recorded for various morpho-physiological, grain, fodder yield and quality traits. Data was statistically analyzed to check significance of results at <0.05% probability level. It was concluded from heritability, genetic advance, stepwise multiple linear regression, principle component and factor analysis that the selection on the basis of grain yield, green fodder yield, stem diameter, cob weight, stomata conductance, chlorophyll contents, photosynthetic rate, cob length, grain protein, grain oil, embryo percentage and grain starch may be fruitful keeping in view as the major contributing traits to improve crop yield and production. It was suggested that the transgenic lines for glyphosate resistance may be used to develop transgenic hybrids and synthetic varieties with higher grain yield with high quality.

  10. A critical care monitoring system for depth of anaesthesia analysis based on entropy analysis and physiological information database.

    Science.gov (United States)

    Wei, Qin; Li, Yang; Fan, Shou-Zen; Liu, Quan; Abbod, Maysam F; Lu, Cheng-Wei; Lin, Tzu-Yu; Jen, Kuo-Kuang; Wu, Shang-Ju; Shieh, Jiann-Shing

    2014-09-01

    Diagnosis of depth of anaesthesia (DoA) plays an important role in treatment and drug usage in the operating theatre and intensive care unit. With the flourishing development of analysis methods and monitoring devices for DoA, a small amount of physiological data had been stored and shared for further researches. In this paper, a critical care monitoring (CCM) system for DoA monitoring and analysis was designed and developed, which includes two main components: a physiologic information database (PID) and a DoA analysis subsystem. The PID, including biologic data and clinical information was constructed through a browser and server model so as to provide a safe and open platform for storage, sharing and further study of clinical anaesthesia information. In the analysis of DoA, according to our previous studies on approximate entropy, sample entropy (SampEn) and multi-scale entropy (MSE), the SampEn and MSE were integrated into the subsystem for indicating the state of patients underwent surgeries in real time because of their stability. Therefore, this CCM system not only supplies the original biological data and information collected from the operating room, but also shares our studies for improvement and innovation in the research of DoA.

  11. Automated phenotyping of plant shoots using imaging methods for analysis of plant stress responses - a review.

    Science.gov (United States)

    Humplík, Jan F; Lazár, Dušan; Husičková, Alexandra; Spíchal, Lukáš

    2015-01-01

    Current methods of in-house plant phenotyping are providing a powerful new tool for plant biology studies. The self-constructed and commercial platforms established in the last few years, employ non-destructive methods and measurements on a large and high-throughput scale. The platforms offer to certain extent, automated measurements, using either simple single sensor analysis, or advanced integrative simultaneous analysis by multiple sensors. However, due to the complexity of the approaches used, it is not always clear what such forms of plant phenotyping can offer the potential end-user, i.e. plant biologist. This review focuses on imaging methods used in the phenotyping of plant shoots including a brief survey of the sensors used. To open up this topic to a broader audience, we provide here a simple introduction to the principles of automated non-destructive analysis, namely RGB, chlorophyll fluorescence, thermal and hyperspectral imaging. We further on present an overview on how and to which extent, the automated integrative in-house phenotyping platforms have been used recently to study the responses of plants to various changing environments.

  12. Leaf d15N as a physiological indicator of the responsiveness of N2-fixing alfalfa plants to elevated [CO2], temperature and low water availability

    Directory of Open Access Journals (Sweden)

    Idoia eAriz

    2015-08-01

    Full Text Available The natural 15N/14N isotope composition (δ15N of a tissue is a consequence of its N source and N physiological mechanisms in response to the environment. It could potentially be used as a tracer of N metabolism in plants under changing environmental conditions, where primary N metabolism may be complex, and losses and gains of N fluctuate over time. In order to test the utility of δ15N as an indicator of plant N status in N2-fixing plants grown under various environmental conditions, alfalfa (Medicago sativa L. plants were subjected to distinct conditions of [CO2] (400 versus 700 mol mol-1, temperature (ambient versus ambient + 4ºC and water availability (fully watered versus water deficiency - WD. As expected, increased [CO2] and temperature stimulated photosynthetic rates and plant growth, whereas these parameters were negatively affected by WD. The determination of δ15N in leaves, stems, roots and nodules showed that leaves were the most representative organs of the plant response to increased [CO2] and WD. Depletion of heavier N isotopes in plants grown under higher [CO2] and WD conditions reflected decreased transpiration rates, but could also be related to a higher N demand in leaves, as suggested by the decreased leaf N and total soluble protein (TSP contents detected at 700 mol mol-1 [CO2] and WD conditions. In summary, leaf δ15N provides relevant information integrating parameters which condition plant responsiveness (e.g. photosynthesis, TSP, N demand and water transpiration to environmental conditions.

  13. Genome-wide identification and expression analysis of rice pectin methylesterases: Implication of functional roles of pectin modification in rice physiology.

    Science.gov (United States)

    Jeong, Ho Young; Nguyen, Hong Phuong; Lee, Chanhui

    2015-07-01

    Pectin, which is enriched in primary cell walls and middle lamellae, is an essential polysaccharide in all higher plants. Homogalacturonans (HGA), a major form of pectin, are synthesized and methylesterified by enzymes localized in the Golgi apparatus and transported into the cell wall. Depending on cell type, the degree and pattern of pectin methylesterification are strictly regulated by cell wall-localized pectin methylesterases (PMEs). Despite its importance in plant development and growth, little is known about the physiological functions of pectin in rice, which contains 43 different types of PME. The presence of pectin in rice cell walls has been substantiated by uronic acid quantification and immunodetection of JIM7 monoclonal antibodies. We performed PME activity assays with cell wall proteins isolated from different rice tissues. In accordance with data from Arabidopsis, the highest activity was observed in germinating tissues, young culm, and spikelets, where cells are actively elongating. Transcriptional profiling of OsPMEs by real-time PCR and meta-analysis indicates that PMEs exhibit spatial- and stress-specific expression patterns during rice development. Based on in silico analysis, we identified subcellular compartments, isoelectric point, and cleavage sites of OsPMEs. Our findings provide an important tool for further studies seeking to unravel the functional importance of pectin modification during plant growth and abiotic and biotic responses of grass plants.

  14. The impact of "physiological correction" on functional connectivity analysis of pharmacological resting state fMRI

    NARCIS (Netherlands)

    Khalili-Mahani, N.; Chang, C.; Osch, M.J.; Veer, I.M.; Buchem, van M.A.; Dahan, A.; Beckmann, C.F.

    2013-01-01

    Growing interest in pharmacological resting state fMRI (RSfMRI) necessitates developing standardized and robust analytical approaches that are insensitive to spurious correlated physiological signals. However, in pharmacological experiments physiological variations constitute an important aspect of

  15. Progression Analysis and Stage Discovery in Continuous Physiological Processes Using Image Computing

    Directory of Open Access Journals (Sweden)

    Ferrucci Luigi

    2010-01-01

    Full Text Available We propose an image computing-based method for quantitative analysis of continuous physiological processes that can be sensed by medical imaging and demonstrate its application to the analysis of morphological alterations of the bone structure, which correlate with the progression of osteoarthritis (OA. The purpose of the analysis is to quantitatively estimate OA progression in a fashion that can assist in understanding the pathophysiology of the disease. Ultimately, the texture analysis will be able to provide an alternative OA scoring method, which can potentially reflect the progression of the disease in a more direct fashion compared to the existing clinically utilized classification schemes based on radiology. This method can be useful not just for studying the nature of OA, but also for developing and testing the effect of drugs and treatments. While in this paper we demonstrate the application of the method to osteoarthritis, its generality makes it suitable for the analysis of other progressive clinical conditions that can be diagnosed and prognosed by using medical imaging.

  16. 丛枝菌根对植物生理代谢的影响%Effects of VA Mycorrhiza on Physiology and Metabolism of Plant

    Institute of Scientific and Technical Information of China (English)

    范继红; 韩振芹; 陈秀新

    2012-01-01

    Based on extensive literatures both at home and abroad,the research progress in the nutritional physiology and resistant physiology of VA mycorrhiza was analyzed,especially its functions in promoting the nutrients uptake,and improving the stress resistance and disease resistance of host plants.%参阅国内外大量文献,分析了丛枝菌根在营养生理及抗性生理方面的研究进展.同时,重点就丛枝菌根在促进宿主植物对氯、磷等营养元素的吸收、提高宿主植物抗逆性及抗病性研究进展进行了阐述.

  17. Metabolism analysis and on-line physiological state diagnosis of acetone-butanol fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Chauvatcharin, S.; Seki, Tatsuji; Takagi, Mutsumi; Yoshida, Toshiomi [Osaka Univ., Suita, Osaka (Japan). International Center of Cooperative Research in Biotechnology; Siripatana, C. [Prince of Songkla Univ., Bangkok (Thailand). Dept. of Industrial Biotechnology

    1998-06-20

    Fermentation equations for acetone-butanol (AB) were applied in a metabolic analysis of the reaction network under various conditions; that is, at different pHs and a high NADH{sub 2} turnover rate using methyl viologen, in a Clostridium acetobutylicum culture. The results disclosed variations in the pattern of rate changes that reflected changes in the physiological state. A liner relationship was found to exist between NADH{sub 2} generation and butanol production rate. By coupling an automated measurement system with the fermentation model, on-line estimation of the culture state was accomplished. Based on the AB fermentation model, new parameters were defined for on-line diagnosis of the physiological state and determination of the best timing for amplifying NADH{sub 2} generation by the addition of methyl viologen to obtain a high level of butanol productivity. A potential means of achieving optimal control for a high level of solvent production, involving the correlation of certain rates, is proposed.

  18. Why Fish Oil Fails: A Comprehensive 21st Century Lipids-Based Physiologic Analysis

    Directory of Open Access Journals (Sweden)

    B. S. Peskin

    2014-01-01

    Full Text Available The medical community suffered three significant fish oil failures/setbacks in 2013. Claims that fish oil’s EPA/DHA would stop the progression of heart disease were crushed when The Risk and Prevention Study Collaborative Group (Italy released a conclusive negative finding regarding fish oil for those patients with high risk factors but no previous myocardial infarction. Fish oil failed in all measures of CVD prevention—both primary and secondary. Another major 2013 setback occurred when fish oil’s DHA was shown to significantly increase prostate cancer in men, in particular, high-grade prostate cancer, in the Selenium and Vitamin E Cancer Prevention Trial (SELECT analysis by Brasky et al. Another monumental failure occurred in 2013 whereby fish oil’s EPA/DHA failed to improve macular degeneration. In 2010, fish oil’s EPA/DHA failed to help Alzheimer’s victims, even those with low DHA levels. These are by no means isolated failures. The promise of fish oil and its so-called active ingredients EPA / DHA fails time and time again in clinical trials. This lipids-based physiologic review will explain precisely why there should have never been expectation for success. This review will focus on underpublicized lipid science with a focus on physiology.

  19. Next Generation Nuclear Plant GAP Analysis Report

    Energy Technology Data Exchange (ETDEWEB)

    Ball, Sydney J [ORNL; Burchell, Timothy D [ORNL; Corwin, William R [ORNL; Fisher, Stephen Eugene [ORNL; Forsberg, Charles W. [Massachusetts Institute of Technology (MIT); Morris, Robert Noel [ORNL; Moses, David Lewis [ORNL

    2008-12-01

    As a follow-up to the phenomena identification and ranking table (PIRT) studies conducted recently by NRC on next generation nuclear plant (NGNP) safety, a study was conducted to identify the significant 'gaps' between what is needed and what is already available to adequately assess NGNP safety characteristics. The PIRT studies focused on identifying important phenomena affecting NGNP plant behavior, while the gap study gives more attention to off-normal behavior, uncertainties, and event probabilities under both normal operation and postulated accident conditions. Hence, this process also involved incorporating more detailed evaluations of accident sequences and risk assessments. This study considers thermal-fluid and neutronic behavior under both normal and postulated accident conditions, fission product transport (FPT), high-temperature metals, and graphite behavior and their effects on safety. In addition, safety issues related to coupling process heat (hydrogen production) systems to the reactor are addressed, given the limited design information currently available. Recommendations for further study, including analytical methods development and experimental needs, are presented as appropriate in each of these areas.

  20. Autochthonous arbuscular mycorrhizal fungi and Bacillus thuringiensis from a degraded Mediterranean area can be used to improve physiological traits and performance of a plant of agronomic interest under drought conditions.

    Science.gov (United States)

    Armada, Elisabeth; Azcón, Rosario; López-Castillo, Olga M; Calvo-Polanco, Mónica; Ruiz-Lozano, Juan Manuel

    2015-05-01

    Studies have shown that some microorganisms autochthonous from stressful environments are beneficial when used with autochthonous plants, but these microorganisms rarely have been tested with allochthonous plants of agronomic interest. This study investigates the effectiveness of drought-adapted autochthonous microorganisms [Bacillus thuringiensis (Bt) and a consortium of arbuscular mycorrhizal (AM) fungi] from a degraded Mediterranean area to improve plant growth and physiology in Zea mays under drought stress. Maize plants were inoculated or not with B. thuringiensis, a consortium of AM fungi or a combination of both microorganisms. Plants were cultivated under well-watered conditions or subjected to drought stress. Several physiological parameters were measured, including among others, plant growth, photosynthetic efficiency, nutrients content, oxidative damage to lipids, accumulation of proline and antioxidant compounds, root hydraulic conductivity and the expression of plant aquaporin genes. Under drought conditions, the inoculation of Bt increased significantly the accumulation of nutrients. The combined inoculation of both microorganisms decreased the oxidative damage to lipids and accumulation of proline induced by drought. Several maize aquaporins able to transport water, CO2 and other compounds were regulated by the microbial inoculants. The impact of these microorganisms on plant drought tolerance was complementary, since Bt increased mainly plant nutrition and AM fungi were more active improving stress tolerance/homeostatic mechanisms, including regulation of plant aquaporins with several putative physiological functions. Thus, the use of autochthonous beneficial microorganisms from a degraded Mediterranean area is useful to protect not only native plants against drought, but also an agronomically important plant such as maize.

  1. Comprehensive analysis of plant rapid alkalization factor (RALF) genes.

    Science.gov (United States)

    Sharma, Arti; Hussain, Adil; Mun, Bong-Gyu; Imran, Qari Muhammad; Falak, Noreen; Lee, Sang-Uk; Kim, Jae Young; Hong, Jeum Kyu; Loake, Gary John; Ali, Asad; Yun, Byung-Wook

    2016-09-01

    Receptor mediated signal carriers play a critical role in the regulation of plant defense and development. Rapid alkalization factor (RALF) proteins potentially comprise important signaling components which may have a key role in plant biology. The RALF gene family contains large number of genes in several plant species, however, only a few RALF genes have been characterized to date. In this study, an extensive database search identified 39, 43, 34 and 18 RALF genes in Arabidopsis, rice, maize and soybean, respectively. These RALF genes were found to be highly conserved across the 4 plant species. A comprehensive analysis including the chromosomal location, gene structure, subcellular location, conserved motifs, protein structure, protein-ligand interaction and promoter analysis was performed. RALF genes from four plant species were divided into 7 groups based on phylogenetic analysis. In silico expression analysis of these genes, using microarray and EST data, revealed that these genes exhibit a variety of expression patterns. Furthermore, RALF genes showed distinct expression patterns of transcript accumulation in vivo following nitrosative and oxidative stresses in Arabidopsis. Predicted interaction between RALF and heme ligand also showed that RALF proteins may contribute towards transporting or scavenging oxygen moieties. This suggests a possible role for RALF genes during changes in cellular redox status. Collectively, our data provides a valuable resource to prime future research in the role of RALF genes in plant growth and development.

  2. Real-time analysis of water movement in plant sample

    Energy Technology Data Exchange (ETDEWEB)

    Yokota, Harumi; Furukawa, Jun; Tanoi, Keitaro [Graduate School, Tokyo Univ. (Japan)

    2000-07-01

    To know the effect of drought stress on two cultivars of cowpea, drought tolerant (DT) and drought sensitive (DS), and to estimate vanadium treatment on plant activity, we performed real time{sup 18}F labeled water uptake measurement by PETIS. Fluoride-18 was produced by bombarding a cubic ice target with 50 MeV protons using TIARA AVF cyclotron. Then {sup 18}F labeled water was applied to investigate water movement in a cowpea plant. Real time water uptake manner could be monitored by PETIS. After the analysis by PETIS, we also measured the distribution of {sup 18}F in a whole plant by BAS. When a cowpea plant was treated with drought stress, there was a difference in water uptake manner between DT and DS cultivar. When a cowpea plant was treated with V for 20 hours before the water uptake experiment, the total amount of {sup 18}F labeled water absorption was found to be drastically decreased. (author)

  3. Morphological and physiological characteristics of rapeseed plants regenerated in vitro from thin cell layers in the presence of zinc.

    Science.gov (United States)

    Ben Ghnaya, Asma; Charles, Gilbert; Hourmant, Annick; Ben Hamida, Jeannette; Branchard, Michel

    2007-10-01

    Phytoremediation offers owners and managers of metal-contaminated sites an innovative and cost-effective option to address recalcitrant environmental contamination. The use of plants to restore or stabilize contaminated sites, known as phytoremediation, takes advantage of the natural abilities of plants to take up, accumulate or store metals. This includes the use of plants that tolerate and accumulate metals at high levels for phytoextraction and the use of plants growing under conditions that are toxic to other plants, for preventing, for example, soil erosion (phytostabilisation). Rapeseed (Brassica napus L.) was shown to be able to accumulate substantial amounts of metals combined with high biomass. Brassica napus was therefore selected for heavy metal (HM) tolerance and accumulation through in vitro selection. A selective pressure applied during the neoformation process from transversal thin cell layers (tTCLs) allowed us to select tolerant cells and tissues. Toxic metals (such as Zn) were added to the culture media in order to select zinc-tolerant plants. Exerting a selective pressure during tTCLs regeneration aimed at selecting plants with exceptional zinc tolerance and/or accumulating capacity. The morphological and physicochemical characteristics of regenerated plants cultivated in greenhouse appeared to depend very significantly on the concentration of ZnSO(4) applied during the neoformation process. Plants regenerated in the presence of ZnSO(4) at 100 microM exhibited a greater size and a higher biomass together with flowering precocity. The contents of zinc, chlorophyll, and proline were modified in the regenerated plants. Pre-treatment with an excess of ZnSO(4) (>500 microM) was responsible for a percentage of tTCLs intolerance above 96%. With lower Zn concentrations (100-250 microM), the survival rates (33-15%) were higher.

  4. Graphical analysis of French nuclear power plant production date

    Energy Technology Data Exchange (ETDEWEB)

    Jourdan, J.P. [Electricite de France (EDF), Projet Production EPR 1, 93 - Saint-Denis (France)

    2001-07-01

    The analysis of values of plant production uses here an original method of graphical analysis. This method clarifies various difficulties of analysing big experience feedback databases among which the language interpretation and distinctions between scarce events and multi-annual events. In general, the method shows the logical processes that production values obey (pure chance logic, administrative logic, and willpower) This method of graphical analysis provides a tool to observe and question in a concrete way so that each person involved can put the events in which he played a role into the general context of other plants. It is a deductible method to improve this big and complex system. (author)

  5. Economic analysis of large solar power plants

    Science.gov (United States)

    Klaiss, Helmut; Nitsch, Joachim; Geyer, Michael

    1987-11-01

    The current status and future potential of solar-tower, parabolic-reflector/Stirling-engine, channel-collector, and photovoltaic solar power plants of capacity 10 MWe or more are discussed. Consideration is given to the geographic and technological limitations, initial investment and operating costs, presently operating facilities, market openings, and critical technological challenges controlling future expansion. Numerical data are presented in tables and graphs, and it is concluded that solar power production will soon become economically competitive. It is suggested that the channel collector, at present the most mature and cost-efficient technology, has the least potential for further improvement, and that parabolic/Stirling and photovoltaic systems are probably better suited to smaller applications than to large-scale commercial power production.

  6. Science and Measurement Requirements for a Plant Physiology and Functional Types Mission: Measuring the Composition, Function and Health of Global Land and Coastal Ocean Ecosystems

    Science.gov (United States)

    Green, Robert O.; Rogez, Francois; Green, Rob; Ungar, Steve; Knox, Robert; Asner, Greg; Muller-Karger, Frank; Bissett, Paul; Chekalyuk, Alex; Dierssen, Heidi; Gamon, John; Hook, Simon; Meister, Gerhard; Middleton, Betsy; Ollinger, Scott; Roberts, Dar; Siegel, Dave; Townsend, Phil; Saatchi, Sassan; Unstin, Susan; Turner, Woody; Wickland, Diane; Bontempi, Paula; Emanuel, Bill

    2007-01-01

    This slide presentation reviews the proposed Plant Physiology and Functional Types (PPFT) Mission. The National Academy of Sciences Decadal Survey, placed a critical priority on a Mission to observe distribution and changes in ecosystem functions. The PPFT satellite mission provides the essential measurements needed to assess drivers of change in biodiversity and ecosystem services that affect human welfare. The presentation reviews the science questions that the mission will be designed to answer, the science rationale, the science measurements, the mission concept, the planned instrumentation, the calibration method, and key signal to noise ratios and uniformity requirements.

  7. Research Progress on Plant Physiological Processes in Response to Climate Change%植物对气候变化生理响应研究进展

    Institute of Scientific and Technical Information of China (English)

    冯彩云; 许新桥; 马月萍; 孙振元; 冯世强

    2012-01-01

    Since the industrial revolution, human activities, especially in the developed countries, have consumed a great amount of resources and energy in the process of industrialization, which have resulted in the increased concentration of greenhouse gases in the air and triggered the global climate change. The change has not only brought severe challenges to human survival and development, but also imposed impacts on the physiological processes of plants. The influences on plant physiological processes by enriching CO2, changing climate factors and environmental stress factors have attracted wide concerns of scientists. This paper attempted to classify and analyze the national and international research on the influence of climate change on plant physiological processes carried out in recent years, and described the research progress of plant physiological response to CO2, temperature and moisture. Finally, the future research directions were prospected.%自工业革命以来,人类活动尤其是发达国家在工业化过程中消耗大量资源、能源,造成大气中温室气体浓度增加,引起全球范围内的气候变化,给人类的生存和发展带来严峻挑战,也对植物的生理过程产生了影响。关于CO2浓度升高及其与气候因子和环境胁迫因子对植物生理过程的影响已引起各国科学家广泛关注。文中就近年来气候变化对植物生理过程的影响国内外研究进行归类和分析,介绍了植物对CO2、温度、水分等因素变化的响应过程研究进展,并提出对进一步研究的展望。

  8. The combined effect of salinity and heat reveals a specific physiological, biochemical and molecular response in tomato plants.

    Science.gov (United States)

    Rivero, Rosa M; Mestre, Teresa C; Mittler, Ron; Rubio, Francisco; Garcia-Sanchez, Francisco; Martinez, Vicente

    2014-05-01

    Many studies have described the response mechanisms of plants to salinity and heat applied individually; however, under field conditions some abiotic stresses often occur simultaneously. Recent studies revealed that the response of plants to a combination of two different stresses is specific and cannot be deduced from the stresses applied individually. Here, we report on the response of tomato plants to a combination of heat and salt stress. Interestingly, and in contrast to the expected negative effect of the stress combination on plant growth, our results show that the combination of heat and salinity provides a significant level of protection to tomato plants from the effects of salinity. We observed a specific response of plants to the stress combination that included accumulation of glycine betaine and trehalose. The accumulation of these compounds under the stress combination was linked to the maintenance of a high K(+) concentration and thus a lower Na(+) /K(+) ratio, with a better performance of the cell water status and photosynthesis as compared with salinity alone. Our findings unravel new and unexpected aspects of the response of plants to stress combination and provide a proposed list of enzymatic targets for improving crop tolerance to the abiotic field environment.

  9. Evidence of translocation and physiological impacts of foliar applied CeO2 nanoparticles on cucumber (Cucumis sativus) plants.

    Science.gov (United States)

    Hong, Jie; Peralta-Videa, Jose R; Rico, Cyren; Sahi, Shivendra; Viveros, Marian N; Bartonjo, Jane; Zhao, Lijuan; Gardea-Torresdey, Jorge L

    2014-04-15

    Currently, most of the nanotoxicity studies in plants involve exposure to the nanoparticles (NPs) through the roots. However, plants interact with atmospheric NPs through the leaves, and our knowledge on their response to this contact is limited. In this study, hydroponically grown cucumber (Cucumis sativus) plants were aerially treated either with nano ceria powder (nCeO2) at 0.98 and 2.94 g/m(3) or suspensions at 20, 40, 80, 160, and 320 mg/L. Fifteen days after treatment, plants were analyzed for Ce uptake by using ICP-OES and TEM. In addition, the activity of three stress enzymes was measured. The ICP-OES results showed Ce in all tissues of the CeO2 NP treated plants, suggesting uptake through the leaves and translocation to the other plant parts. The TEM results showed the presence of Ce in roots, which corroborates the ICP-OES results. The biochemical assays showed that catalase activity increased in roots and ascorbate peroxidase activity decreased in leaves. Our findings show that atmospheric NPs can be taken up and distributed within plant tissues, which could represent a threat for environmental and human health.

  10. Application of continuous light in a plant factory system 4. Physiological changes and concept of injury induction in plant leaves under continuous light

    OpenAIRE

    畑, 直樹; 桝田, 正治; 村上,賢治; 小林, 昭雄

    2012-01-01

    Physiological changes and concept of injury induction occurring under continuous light are comprehensively reviewed. Continuous light usually reduces photosynthetic rate, which may relate to changes in transpiration and leaf necrosis caused by reactive oxygen species. Other factors apart from photosynthesis may also affect leaf injuries occurring under continuous light. Continuous light sometimes increases carbohydrate and some secondary metabolite contents.

  11. Integrated Network Analysis and Effective Tools in Plant Systems Biology

    Directory of Open Access Journals (Sweden)

    Atsushi eFukushima

    2014-11-01

    Full Text Available One of the ultimate goals in plant systems biology is to elucidate the genotype-phenotype relationship in plant cellular systems. Integrated network analysis that combines omics data with mathematical models has received particular attention. Here we focus on the latest cutting-edge computational advances that facilitate their combination. We highlight (1 network visualization tools, (2 pathway analyses, (3 genome-scale metabolic reconstruction, and (4 the integration of high-throughput experimental data and mathematical models. Multi-omics data that contain the genome, transcriptome, proteome, and metabolome and mathematical models are expected to integrate and expand our knowledge of complex plant metabolisms.

  12. BIOMETRIC AND PHYSIOLOGICAL CHARACTERISTICS OF CHRYSANTHEMUM (CHRYSANTHEMUM INDICUM L. PLANTS GROWN AT DIFFERENT RATES OF NITROGEN FERTILIZATION

    Directory of Open Access Journals (Sweden)

    V IVANOVA

    2003-07-01

    Full Text Available A trial with large the flowered chrysanthemum cultivar Dark Westland was carried out in an unheated greenhouse. Three rates of nitrogen fertilization were studied: 0, 100 and 140 kgN/ha, as well as two modes of plant formation – single- and two-stemmed plants. Parameters of the biometric characteristics, leaf gasexchange and leaf pigment content were determined. The best results about growth and decorative behaviour were achieved at nitrogen fertilization level of 100 kgN/ha. It was established that nitrogen fertilization in rates of 100 and 140 kgN/ha enhances photosynthetic rate in both modes of plant formation.

  13. Monitoring yeast physiology during very high gravity wort fermentations by frequent analysis of gene expression.

    Science.gov (United States)

    Rautio, Jari J; Huuskonen, Anne; Vuokko, Heikki; Vidgren, Virve; Londesborough, John

    2007-09-01

    Brewer's yeast experiences constantly changing environmental conditions during wort fermentation. Cells can rapidly adapt to changing surroundings by transcriptional regulation. Changes in genomic expression can indicate the physiological condition of yeast in the brewing process. We monitored, using the transcript analysis with aid of affinity capture (TRAC) method, the expression of some 70 selected genes relevant to wort fermentation at high frequency through 9-10 day fermentations of very high gravity wort (25 degrees P) by an industrial lager strain. Rapid changes in expression occurred during the first hours of fermentations for several genes, e.g. genes involved in maltose metabolism, glycolysis and ergosterol synthesis were strongly upregulated 2-6 h after pitching. By the time yeast growth had stopped (72 h) and total sugars had dropped by about 50%, most selected genes had passed their highest expression levels and total mRNA was less than half the levels during growth. There was an unexpected upregulation of some genes of oxygen-requiring pathways during the final fermentation stages. For five genes, expression of both the Saccharomyces cerevisiae and S. bayanus components of the hybrid lager strain were determined. Expression profiles were either markedly different (ADH1, ERG3) or very similar (MALx1, ILV5, ATF1) between these two components. By frequent analysis of a chosen set of genes, TRAC provided a detailed and dynamic picture of the physiological state of the fermenting yeast. This approach offers a possible way to monitor and optimize the performance of yeast in a complex process environment.

  14. Nitrogen level and physiological basis of yield of mungbean at varying plant population in High Ganges River Flood Plain soil of Bangladesh.

    Science.gov (United States)

    Mian, M A K; Hossain, J

    2014-07-01

    A field experiment was conducted at the Regional Agricultural Research Station of Bangladesh Agricultural Research Institute, Jessore during early kharif season of 2009 and 2010 to observe the effect of nitrogen on the physiological basis of yield of mungbean at varying plant population. In the experiment, four nitrogen levels (N0, N40, N60 and N80 kg ha(-1)) were assigned in the main plots and three plant population (P30, P35 and P40 m(-2)) in the sub plots. The results revealed that mungbean showed better growth in N60 and N80 kg ha(-1) representing higher values of CGR, TDM, LAI and plant height while N40 exhibited intermediate growth. Again, growth of mungbean was better in higher plant population (35-40 m(-2)) representing higher values of growth parameters. Seed yield of mungbean was obtained the highest (1908 kg ha(-1)) associated with the highest No. of pods plant(-1) (29.98), seeds pod(-1) (10.41) and 1000-seed weight (37.70 g) in N40 kg ha(-1). Further, seed yield of mungbean was the highest (1919 kg ha(-1)) in plant population of 40 m(-2). In interaction, seed yield was the highest (1963 kg ha(-1)) in N40 kg ha(-1) with plant population of 40 m(-2). The effect of applied nitrogen on the seed yield of mungbean can be explained 78% (R2 = 0.78) by this function (Y = 1540.70+16.069x-0.173x2). The optimum nitrogen level was 46 kg ha(-1) by using the developed functional model and then the predicted seed yield of mungbean would be 1944 kg ha(-1).

  15. Research Progress on the use of Plant Allelopathy in Agriculture and the Physiological and Ecological Mechanisms of Allelopathy

    OpenAIRE

    Fang eCheng; Zhihui eCheng

    2015-01-01

    Allelopathy is a common biological phenomenon by which one organism produces biochemicals that influence the growth, survival, development, and reproduction of other organisms. These biochemicals are known as allelochemicals and have beneficial or detrimental effects on target organisms. Plant allelopathy is one of the modes of interaction between receptor and donor plants and may exert either positive effects (e.g., for agricultural management, such as weed control, crop protection, or crop ...

  16. Growth Limitations and Physiological Advantages in Crop Plants Grown with Organic Fertilization%有机栽培对作物生产的影响--植株生长的局限和生理活性的优势

    Institute of Scientific and Technical Information of China (English)

    徐会连

    2001-01-01

    Organic and chemical fertilizers were applied to sweet com, tomato and other crops to compare the growth, yield, physiological responses and resistance to water stress and diseases. Several mathematical ap proaches to physiological analysis were used in this research. Organic fertilizers promoted root growth and ac tivity and enhanced photosynthesis in most crop plants at the later growth stages although the seedling growth was lower at the early stage. Analysis of declining photosynthetic curve with time in the excised corn leaves showed that leaves of corn plants fertilized with organic materials possessed a higher photosynthetic maintain ing ability, which was consistent with the results of water stress avoidance. It is concluded that organic fertilized crop plants possess higher physiological activities and higher environ mental stresses resistance with higher quality in the edible parts, but lower nutrient availability at the early stage usually limits the seedling growth, compared with the chemical fertilized control plants%本研究就有机栽培和化肥栽培的玉米,西红柿和其它作物,在营养体生长,经济产量以及对水分胁迫和病害的反应方面进行了比较.另外,本文在生理学分析方面采用几种新颖的数学方法.研究结果证明,尽管苗期生长不尽如意,但有机肥料促进根系的营养体生长以及生理活性,从而能使大多数作物的中后期光合活性增强.对切断叶的光合作用降低曲线的分析证实有机栽培的作物在彻底断水的情况下具有较强的光合活性维持能力.这与以前报道的水分胁迫回避性是一致的.因此可以下结论说,与化肥栽培的作物相比,有机栽培的作物其生理活性高,环境胁迫抗性强,可食部位的营养质量高,但是苗期生长往往受可给态养分不足的限制.

  17. Functional analysis of plant idioblasts (Myrosin cells) and their role in defense, development and growth.

    OpenAIRE

    Borgen, Birgit Hafeld

    2002-01-01

    Glucosinolates are natural plant products known as flavor compounds, cancerpreventing agents, and biopesticides. There is a strong interest in controlling the level of glucosinolates to improve flavor and nutritional qualities of food crops and to study the physiological role of glucosinolates in plants. The role of the myrosinaseglucosinolate system in plant defense-related reactions of Cruciferae is accepted. As metabolism of glucosinolates in healthy intact plants has been reported, this i...

  18. Analysis of gas exchange, stomatal behaviour and micronutrients uncovers dynamic response and adaptation of tomato plants to monochromatic light treatments.

    Science.gov (United States)

    O'Carrigan, Andrew; Babla, Mohammad; Wang, Feifei; Liu, Xiaohui; Mak, Michelle; Thomas, Richard; Bellotti, Bill; Chen, Zhong-Hua

    2014-09-01

    Light spectrum affects the yield and quality of greenhouse tomato, especially over a prolonged period of monochromatic light treatments. Physiological and chemical analysis was employed to investigate the influence of light spectral (blue, green and red) changes on growth, photosynthesis, stomatal behaviour, leaf pigment, and micronutrient levels. We found that plants are less affected under blue light treatment, which was evident by the maintenance of higher A, gs, Tr, and stomatal parameters and significantly lower VPD and Tleaf as compared to those plants grown in green and red light treatments. Green and red light treatments led to significantly larger increase in the accumulation of Fe, B, Zn, and Cu than blue light. Moreover, guard cell length, width, and volume all showed highly significant positive correlations to gs, Tr and negative links to VPD. There was negative impact of monochromatic lights-induced accumulation of Mn, Cu, and Zn on photosynthesis, leaf pigments and plant growth. Furthermore, most of the light-induced significant changes of the physiological traits were partially recovered at the end of experiment. A high degree of morphological and physiological plasticity to blue, green and red light treatments suggested that tomato plants may have developed mechanisms to adapt to the light treatments. Thus, understanding the optimization of light spectrum for photosynthesis and growth is one of the key components for greenhouse tomato production.

  19. Arabidopsis transcriptome analysis reveals key roles of melatonin in plant defense systems.

    Directory of Open Access Journals (Sweden)

    Sarah Weeda

    Full Text Available Melatonin is a ubiquitous molecule and exists across kingdoms including plant species. Studies on melatonin in plants have mainly focused on its physiological influence on growth and development, and on its biosynthesis. Much less attention has been drawn to its affect on genome-wide gene expression. To comprehensively investigate the role(s of melatonin at the genomics level, we utilized mRNA-seq technology to analyze Arabidopsis plants subjected to a 16-hour 100 pM (low and 1 mM (high melatonin treatment. The expression profiles were analyzed to identify differentially expressed genes. 100 pM melatonin treatment significantly affected the expression of only 81 genes with 51 down-regulated and 30 up-regulated. However, 1 mM melatonin significantly altered 1308 genes with 566 up-regulated and 742 down-regulated. Not all genes altered by low melatonin were affected by high melatonin, indicating different roles of melatonin in regulation of plant growth and development under low and high concentrations. Furthermore, a large number of genes altered by melatonin were involved in plant stress defense. Transcript levels for many stress receptors, kinases, and stress-associated calcium signals were up-regulated. The majority of transcription factors identified were also involved in plant stress defense. Additionally, most identified genes in ABA, ET, SA and JA pathways were up-regulated, while genes pertaining to auxin responses and signaling, peroxidases, and those associated with cell wall synthesis and modifications were mostly down-regulated. Our results indicate critical roles of melatonin in plant defense against various environmental stresses, and provide a framework for functional analysis of genes in melatonin-mediated signaling pathways.

  20. Response of soybean rhizosphere communities to human hygiene water addition as determined by community level physiological profiling (CLPP) and terminal restriction fragment length polymorphism (TRFLP) analysis

    Science.gov (United States)

    Kerkhof, L.; Santoro, M.; Garland, J.

    2000-01-01

    In this report, we describe an experiment conducted at Kennedy Space Center in the biomass production chamber (BPC) using soybean plants for purification and processing of human hygiene water. Specifically, we tested whether it was possible to detect changes in the root-associated bacterial assemblage of the plants and ultimately to identify the specific microorganism(s) which differed when plants were exposed to hygiene water and other hydroponic media. Plants were grown in hydroponics media corresponding to four different treatments: control (Hoagland's solution), artificial gray water (Hoagland's+surfactant), filtered gray water collected from human subjects on site, and unfiltered gray water. Differences in rhizosphere microbial populations in all experimental treatments were observed when compared to the control treatment using both community level physiological profiles (BIOLOG) and molecular fingerprinting of 16S rRNA genes by terminal restriction fragment length polymorphism analysis (TRFLP). Furthermore, screening of a clonal library of 16S rRNA genes by TRFLP yielded nearly full length SSU genes associated with the various treatments. Most 16S rRNA genes were affiliated with the Klebsiella, Pseudomonas, Variovorax, Burkholderia, Bordetella and Isosphaera groups. This molecular approach demonstrated the ability to rapidly detect and identify microorganisms unique to experimental treatments and provides a means to fingerprint microbial communities in the biosystems being developed at NASA for optimizing advanced life support operations.

  1. Response of soybean rhizosphere communities to human hygiene water addition as determined by community level physiological profiling (CLPP) and terminal restriction fragment length polymorphism (TRFLP) analysis

    Science.gov (United States)

    Kerkhof, L.; Santoro, M.; Garland, J.

    2000-01-01

    In this report, we describe an experiment conducted at Kennedy Space Center in the biomass production chamber (BPC) using soybean plants for purification and processing of human hygiene water. Specifically, we tested whether it was possible to detect changes in the root-associated bacterial assemblage of the plants and ultimately to identify the specific microorganism(s) which differed when plants were exposed to hygiene water and other hydroponic media. Plants were grown in hydroponics media corresponding to four different treatments: control (Hoagland's solution), artificial gray water (Hoagland's+surfactant), filtered gray water collected from human subjects on site, and unfiltered gray water. Differences in rhizosphere microbial populations in all experimental treatments were observed when compared to the control treatment using both community level physiological profiles (BIOLOG) and molecular fingerprinting of 16S rRNA genes by terminal restriction fragment length polymorphism analysis (TRFLP). Furthermore, screening of a clonal library of 16S rRNA genes by TRFLP yielded nearly full length SSU genes associated with the various treatments. Most 16S rRNA genes were affiliated with the Klebsiella, Pseudomonas, Variovorax, Burkholderia, Bordetella and Isosphaera groups. This molecular approach demonstrated the ability to rapidly detect and identify microorganisms unique to experimental treatments and provides a means to fingerprint microbial communities in the biosystems being developed at NASA for optimizing advanced life support operations.

  2. 草甘膦对植物生理影响的研究进展%Research Progress in the Effects of Glyphosate on Plant Physiology

    Institute of Scientific and Technical Information of China (English)

    张冬; 张宇; 王萌; 郑服丛; 杨叶

    2016-01-01

    草甘膦影响非靶标植物的正常生长和发育。为进一步探究草甘膦在植物中的致毒机理,减轻草甘膦对非靶标植物的药害,介绍了草甘膦除草和代谢机制,概述草甘膦对植物光合作用、碳氮代谢等生理过程的影响,并对草甘膦的研究方向做出展望。%Glyphosate has an influence on the regular growth of non-target plants. To figure out the toxicity mechanism of glyphosate in plants and reduce the injury of glyphosate to non-target plants, this review sheds light on the weeds controlling and metabolism mechanisms of glyphosate, expounds the effects of glyphosate on several physiological processes in the plants, such as photosynthesis, carbon metabolism and nitrogen metabolism, and put forwards some prospectives on further research of glyphosate.

  3. Reproduction, physiology and biochemistry

    Science.gov (United States)

    This chapter summarizes fundamental knowledge and recent discoveries about the reproduction, physiology and biochemistry of plant-parasitic nematodes. Various types of reproduction are reviewed, including sexual reproduction and mitotic and meiotic parthenogenesis. Although much is known about the p...

  4. Research on the Plant Physiological Sensor in China%我国植物生理传感器的研究现状

    Institute of Scientific and Technical Information of China (English)

    邱兆美; 张昆; 毛鹏军

    2013-01-01

      利用传感器测量植物生长状况,用以指导灌溉、施肥以及病虫害防治,可以使植物始终处于最佳生长状态。为此,从植物外部形态特征和内部生理特征两个方面,论述了我国植物生理传感器的研究现状。主要介绍了叶片厚度、叶片面积、果实尺寸、茎秆直径、茎秆液流和植物激素等传感器的工作原理以及应用领域,分析了这些传感器在测量中的优缺点,指出植物生理传感器的高精化和无线化、无损动态监测、新型传感器的开发是今后研究的重点问题。%Using the sensor measuring plant growth , guiding irrigation , fertilization and insect control , it can make plants always growing in the best state .This paper introduces the research status of the plant physiological sensor in China , based on the two aspects of the plant external morphological characteristics and internal features .It mainly narrates the operating principles and application fields of the sensor that measure blade thickness , leaf area , fruit size , stem diame-ter , stem SAP flow and plant hormone ,and analyzes the advantages and disadvantages in the measurement of the sensor . Then it points out that plant growth sensor of high precision and wireless , nondestructively dynamic monitoring and the development of new type sensors are the development trend in the future .

  5. Capacity of the aquatic fern (Salvinia minima Baker) to accumulate high concentrations of nickel in its tissues, and its effect on plant physiological processes.

    Science.gov (United States)

    Fuentes, Ignacio I; Espadas-Gil, Francisco; Talavera-May, Carlos; Fuentes, Gabriela; Santamaría, Jorge M

    2014-10-01

    An experiment was designed to assess the capacity of Salvinia minima Baker to uptake and accumulate nickel in its tissues and to evaluate whether or not this uptake can affect its physiology. Our results suggest that S. minima plants are able to take up high amounts of nickel in its tissues, particularly in roots. In fact, our results support the idea that S. minima might be considered a hyper-accumulator of nickel, as it is able to accumulate 16.3 mg g(-1) (whole plant DW basis). Our results also showed a two-steps uptake pattern of nickel, with a fast uptake of nickel at the first 6 to 12h of being expose to the metal, followed by a slow take up phase until the end of the experiment at 144 h. S. minima thus, may be considered as a fern useful in the phytoremediation of residual water bodies contaminated with this metal. Also from our results, S. minima can tolerate fair concentrations of the metal; however, at concentrations higher than 80 μM Ni (1.5 mg g(-1) internal nickel concentration), its physiological performance can be affected. For instance, the integrity of cell membranes was affected as the metal concentration and exposure time increased. The accumulation of high concentrations of internal nickel did also affect photosynthesis, the efficiency of PSII, and the concentration of photosynthetic pigments, although at a lower extent. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. MATING DESIGNS: HELPFUL TOOL FOR QUANTITATIVE PLANT BREEDING ANALYSIS

    Directory of Open Access Journals (Sweden)

    Athanase Nduwumuremyi

    2013-12-01

    Full Text Available Selection of parental materials and good mating designs in conventional plant breeding are the keys to the successful plant breeding programme. However, there are several factors affecting the choices of mating designs. Mating design refers to the procedure of producing the progenies, in plant breeding, plant breeders and geneticists, theoretically and practically, they use different form of mating designs and arrangements for targeted purpose. The choice of a mating design for estimating genetic variances should be dictated by the objectives of the study, time, space, cost and other biological limitations. In all mating designs, the individuals are taken randomly and crossed to produce progenies which are related to each other as half-sibs or full-sibs. A form of multivariate analysis or the analysis of variance can be adopted to estimate the components of variances. Therefore, this review aimed at highlighting the most used mating design in plant breeding and genetics studies. It provides easy and quick insight of the different form of mating designs and some statistical components for successful plant breeding.

  7. High-throughput Binary Vectors for Plant Gene Function Analysis

    Institute of Scientific and Technical Information of China (English)

    Zhi-Yong Lei; Ping Zhao; Min-Jie Cao; Rong Cui; Xi Chen; Li-Zhong Xiong; Qi-Fa Zhang; David J. Oliver; Cheng-Bin Xiang

    2007-01-01

    A series of high-throughput binary cloning vectors were constructed to facilitate gene function analysis in higher plants. This vector series consists of plasmids designed for plant expression, promoter analysis, gene silencing,and green fluorescent protein fusions for protein localization. These vectors provide for high-throughput and efficient cloning utilizing sites for λ phage integrase/excisionase. In addition, unique restriction sites are incorporated in a multiple cloning site and enable promoter replacement. The entire vector series are available with complete sequence information and detailed annotations and are freely distributed to the scientific community for non-commercial uses.

  8. Petrographic Analysis of Cores from Plant 42

    Science.gov (United States)

    2016-10-01

    27  DISCLAIMER: The contents of this report are not to be used for advertising , publication...Department of the Army position unless so designated by other authorized documents. DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO THE... graphic analysis was polished using diamond incrusted polishing pads. The polished sample was imaged using a Zeiss Stereo Discovery V20 mi- croscope

  9. Plant Phenolics: Extraction, Analysis and Their Antioxidant and Anticancer Properties

    Directory of Open Access Journals (Sweden)

    Jin Dai

    2010-10-01

    Full Text Available Phenolics are broadly distributed in the plant kingdom and are the most abundant secondary metabolites of plants. Plant polyphenols have drawn increasing attention due to their potent antioxidant properties and their marked effects in the prevention of various oxidative stress associated diseases such as cancer. In the last few years, the identification and development of phenolic compounds or extracts from different plants has become a major area of health- and medical-related research. This review provides an updated and comprehensive overview on phenolic extraction, purification, analysis and quantification as well as their antioxidant properties. Furthermore, the anticancer effects of phenolics in-vitro and in-vivo animal models are viewed, including recent human intervention studies. Finally, possible mechanisms of action involving antioxidant and pro-oxidant activity as well as interference with cellular functions are discussed.

  10. Methodological Choices in Muscle Synergy Analysis Impact Differentiation of Physiological Characteristics Following Stroke

    Directory of Open Access Journals (Sweden)

    Caitlin L. Banks

    2017-08-01

    Full Text Available Muscle synergy analysis (MSA is a mathematical technique that reduces the dimensionality of electromyographic (EMG data. Used increasingly in biomechanics research, MSA requires methodological choices at each stage of the analysis. Differences in methodological steps affect the overall outcome, making it difficult to compare results across studies. We applied MSA to EMG data collected from individuals post-stroke identified as either responders (RES or non-responders (nRES on the basis of a critical post-treatment increase in walking speed. Importantly, no clinical or functional indicators identified differences between the cohort of RES and nRES at baseline. For this exploratory study, we selected the five highest RES and five lowest nRES available from a larger sample. Our goal was to assess how the methodological choices made before, during, and after MSA affect the ability to differentiate two groups with intrinsic physiologic differences based on MSA results. We investigated 30 variations in MSA methodology to determine which choices allowed differentiation of RES from nRES at baseline. Trial-to-trial variability in time-independent synergy vectors (SVs and time-varying neural commands (NCs were measured as a function of: (1 number of synergies computed; (2 EMG normalization method before MSA; (3 whether SVs were held constant across trials or allowed to vary during MSA; and (4 synergy analysis output normalization method after MSA. MSA methodology had a strong effect on our ability to differentiate RES from nRES at baseline. Across all 10 individuals and MSA variations, two synergies were needed to reach an average of 90% variance accounted for (VAF. Based on effect sizes, differences in SV and NC variability between groups were greatest using two synergies with SVs that varied from trial-to-trial. Differences in SV variability were clearest using unit magnitude per trial EMG normalization, while NC variability was less sensitive to EMG

  11. Analysis of Plant Breeding on Hadoop and Spark

    Directory of Open Access Journals (Sweden)

    Shuangxi Chen

    2016-01-01

    Full Text Available Analysis of crop breeding technology is one of the important means of computer-assisted breeding techniques which have huge data, high dimensions, and a lot of unstructured data. We propose a crop breeding data analysis platform on Spark. The platform consists of Hadoop distributed file system (HDFS and cluster based on memory iterative components. With this cluster, we achieve crop breeding large data analysis tasks in parallel through API provided by Spark. By experiments and tests of Indica and Japonica rice traits, plant breeding analysis platform can significantly improve the breeding of big data analysis speed, reducing the workload of concurrent programming.

  12. Exergy Analysis of Operating Lignite Fired Thermal Power Plant

    Directory of Open Access Journals (Sweden)

    K. Murugesan

    2009-01-01

    Full Text Available The energy assessment must be made through the energy quantity as well as the quality. But the usual energy analysisevaluates the energy generally on its quantity only. However, the exergy analysis assesses the energy on quantity as well asthe quality. The aim of the exergy analysis is to identify the magnitudes and the locations of real energy losses, in order toimprove the existing systems, processes or components. The present paper deals with an exergy analysis performed on anoperating 50MWe unit of lignite fired steam power plant at Thermal Power Station-I, Neyveli Lignite Corporation Limited,Neyveli, Tamil Nadu, India. The exergy losses occurred in the various subsystems of the plant and their components havebeen calculated using the mass, energy and exergy balance equations. The distribution of the exergy losses in several plantcomponents during the real time plant running conditions has been assessed to locate the process irreversibility. The Firstlaw efficiency (energy efficiency and the Second law efficiency (exergy efficiency of the plant have also been calculated.The comparison between the energy losses and the exergy losses of the individual components of the plant shows that themaximum energy losses of 39% occur in the condenser, whereas the maximum exergy losses of 42.73% occur in the combustor.The real losses of energy which has a scope for the improvement are given as maximum exergy losses that occurredin the combustor.

  13. Analysis of the Influencing Factors of Changes in Foxtail Millet Planting Area in Hebei Province

    Institute of Scientific and Technical Information of China (English)

    Meng; LIU; Yu; ZHAO; Fei; LIU; Shunguo; LI; Guirong; WANG; Xinshi; ZHANG

    2013-01-01

    Since reform and open to the outside world,foxtail millet planting area in Hebei Province has constantly reduced,and its planting region has changed from the whole province into some regions,with obvious changes. In this paper,by using qualitative and quantitative approaches like chart analysis,summarizing,Delphi method and osculating value model,the influencing factors of changes in millet growing region in Hebei Province were studied. The results showed that the changes of millet planting area were closely related to many factors,such as little investment in scientific research,weak policy support,a single consumer product demand,the rapid development of other staple crops, labor migration,relatively low comparative effectiveness and physiological characteristics of the millet itself. Then some suggestions were put forward,such as increasing research support,strengthening scientific research strength,researching and developing deeply processed products, expanding consumer groups,improving millet policy support,providing subsidies for planting the improved varieties,researching and developing various types of machinery,and increasing millet production technology training.

  14. Pervasive and strong effects of plants on soil chemistry: a meta-analysis of individual plant ‘Zinke’ effects

    Science.gov (United States)

    Waring, Bonnie G.; Álvarez-Cansino, Leonor; Barry, Kathryn E.; Becklund, Kristen K.; Dale, Sarah; Gei, Maria G.; Keller, Adrienne B.; Lopez, Omar R.; Markesteijn, Lars; Mangan, Scott; Riggs, Charlotte E.; Rodríguez-Ronderos, María Elizabeth; Segnitz, R. Max; Schnitzer, Stefan A.; Powers, Jennifer S.

    2015-01-01

    Plant species leave a chemical signature in the soils below them, generating fine-scale spatial variation that drives ecological processes. Since the publication of a seminal paper on plant-mediated soil heterogeneity by Paul Zinke in 1962, a robust literature has developed examining effects of individual plants on their local environments (individual plant effects). Here, we synthesize this work using meta-analysis to show that plant effects are strong and pervasive across ecosystems on six continents. Overall, soil properties beneath individual plants differ from those of neighbours by an average of 41%. Although the magnitudes of individual plant effects exhibit weak relationships with climate and latitude, they are significantly stronger in deserts and tundra than forests, and weaker in intensively managed ecosystems. The ubiquitous effects of plant individuals and species on local soil properties imply that individual plant effects have a role in plant–soil feedbacks, linking individual plants with biogeochemical processes at the ecosystem scale. PMID:26224711

  15. Physiological impacts of soil pollution and arsenic uptake in three plant species: Agrostis capillaris, Solanum nigrum and Vicia faba.

    Science.gov (United States)

    Austruy, A; Wanat, N; Moussard, C; Vernay, P; Joussein, E; Ledoigt, G; Hitmi, A

    2013-04-01

    In order to revegetate an industrial soil polluted by trace metals and metalloids (As, Pb, Cu, Cd, Sb), the impact of pollution on three plant species, Solanum nigrum and Agrostis capillaris, both native species in an industrial site, and Vicia faba, a plant model species, is studied. Following the study of soil pollution from the industrial wasteland of Auzon, it appears that the As is the principal pollutant. Particular attention is given to this metalloid, both in its content and its speciation in the soil that the level of its accumulation in plants. In V. faba and A. capillaris, the trace metals and metalloids inhibit the biomass production and involve a lipid peroxidation in the leaves. Furthermore, these pollutants cause a photosynthesis perturbation by stomatal limitations and a dysfunction of photosystem II. Whatever the plant, the As content is less than 0.1 percent of dry matter, the majority of As absorbed is stored in the roots which play the role of trap organ. In parallel, the culture of S. nigrum decreases significantly the exchangeable and weakly adsorbed fraction of As in rhizospheric soil. This study has highlighted the ability of tolerance to trace metals of S. nigrum and to a lesser extent A. capillaris. Our data indicate that V. faba is not tolerant to soil pollution and is not a metallophyte species. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Low level of selenium increases the efficacy of 24-epibrassinolide through altered physiological and biochemical traits of Brassica juncea plants.

    Science.gov (United States)

    Naz, Fatima Salva; Yusuf, Mohammad; Khan, Tanveer A; Fariduddin, Qazi; Ahmad, Aqil

    2015-10-15

    This study was conducted to provide an insight into the effect of Se (through soil) induced changes in Brassica juncea plants in the presence and absence of 24-epibrassinolide (EBL; foliar). The Se treatments showed dual response, 10 μM of Se significantly increased growth, water relations, photosynthetic attributes along with carbonic anhydrase activity whereas its higher concentrations proved inhibitory in concentration dependent manner. The follow-up application of EBL to the Se stressed plants improved growth, water relations, photosynthesis and simultaneously enhanced the various antioxidant enzymes viz. catalase, peroxidase and superoxide dismutase with the excess accumulation of proline. In addition to this, 10 μM Se increases the efficacy of 10(-8) M of EBL and both in combination showed maximum increase for the growth and photosynthetic traits of plants. On the other hand, the elevated level of antioxidant enzymes as well as proline could have conferred tolerance to the Se-stressed plants resulting in improved growth, water relations and photosynthesis.

  17. Recent insights into plant-virus interactions through proteomic analysis.

    Science.gov (United States)

    Di Carli, Mariasole; Benvenuto, Eugenio; Donini, Marcello

    2012-10-05

    Plant viruses represent a major threat for a wide range of host species causing severe losses in agricultural practices. The full comprehension of mechanisms underlying events of virus-host plant interaction is crucial to devise novel plant resistance strategies. Until now, functional genomics studies in plant-virus interaction have been limited mainly on transcriptomic analysis. Only recently are proteomic approaches starting to provide important contributions to this area of research. Classical two-dimensional electrophoresis (2-DE) coupled to mass spectrometry (MS) is still the most widely used platform in plant proteome analysis, although in the last years the application of quantitative "second generation" proteomic techniques (such as differential in gel electrophoresis, DIGE, and gel-free protein separation methods) are emerging as more powerful analytical approaches. Apparently simple, plant-virus interactions reveal a really complex pathophysiological context, in which resistance, defense and susceptibility, and direct virus-induced reactions interplay to trigger expression responses of hundreds of genes. Given that, this review is specifically focused on comparative proteome-based studies on pathogenesis of several viral genera, including some of the most important and widespread plant viruses of the genus Tobamovirus, Sobemovirus, Cucumovirus and Potyvirus. In all, this overview reveals a widespread repression of proteins associated with the photosynthetic apparatus, while energy metabolism/protein synthesis and turnover are typically up-regulated, indicating a major redirection of cell metabolism. Other common features include the modulation of metabolisms concerning sugars, cell wall, and reactive oxigen species as well as pathogenesis-related (PR) proteins. The fine-tuning between plant development and antiviral defense mechanisms determines new patterns of regulation of common metabolic pathways. By offering a 360-degree view of protein modulation

  18. Capacity of the aquatic fern (Salvinia minima Baker) to accumulate high concentrations of nickel in its tissues, and its effect on plant physiological processes

    Energy Technology Data Exchange (ETDEWEB)

    Fuentes, Ignacio I.; Espadas-Gil, Francisco; Talavera-May, Carlos; Fuentes, Gabriela; Santamaría, Jorge M., E-mail: jorgesm@cicy.mx

    2014-10-15

    Highlights: • We document the capacity of an aquatic fern to hyper-accumulate Ni. • Effects of high Ni concentrations uptake on plant performance is documented. • High concentration of Ni in tissues damage photosynthesis. • Damage is related to carboxylation mechanisms than to electron transfer efficiency. • S. minima is a good candidate for remediation of water bodies contaminated with Ni. - Abstract: An experiment was designed to assess the capacity of Salvinia minima Baker to uptake and accumulate nickel in its tissues and to evaluate whether or not this uptake can affect its physiology. Our results suggest that S. minima plants are able to take up high amounts of nickel in its tissues, particularly in roots. In fact, our results support the idea that S. minima might be considered a hyper-accumulator of nickel, as it is able to accumulate 16.3 mg g{sup −1} (whole plant DW basis). Our results also showed a two-steps uptake pattern of nickel, with a fast uptake of nickel at the first 6 to 12 h of being expose to the metal, followed by a slow take up phase until the end of the experiment at 144 h. S. minima thus, may be considered as a fern useful in the phytoremediation of residual water bodies contaminated with this metal. Also from our results, S. minima can tolerate fair concentrations of the metal; however, at concentrations higher than 80 μM Ni (1.5 mg g{sup −1} internal nickel concentration), its physiological performance can be affected. For instance, the integrity of cell membranes was affected as the metal concentration and exposure time increased. The accumulation of high concentrations of internal nickel did also affect photosynthesis, the efficiency of PSII, and the concentration of photosynthetic pigments, although at a lower extent.

  19. Impact of Cinnamic Acid on Physiological and Anatomical Changes in Maize Plants (Zea mays L. Grown under Salinity Stress

    Directory of Open Access Journals (Sweden)

    Pramod Kumar Singh

    2014-05-01

    Full Text Available The environmental contamination with high salt is the elementary intimidation to the agriculture. Maize plants were deeply affected due to salinity worldwide and a severe problem to scientists. A probable survival strategy of the plants under unpleasant environmental circumstances is to use of endogenous metabolites that could ameliorate the harsh effect of salinity. Current study was under taken to observe the effect of cinnamic acid (CA, a central molecule of phenylpropanoid pathway (Secondary metabolism on the growth and development of maize plants under NaCl stress conditions. CA is rapidly produced by plants in response to stressful condition. Response to maize seed to the presoaking treatment 0.05mM CA was deliberated under different concentration of NaCl stress such as 50, 100, 150, 200, mM NaCl for 14 days. The injurious effects of salinity on growth and development were manifested by decreased fresh weight, dry weight, and relative water content (RWC and chlorophyll pigment contents. Degree of lipid peroxidation turned down through the significant decrease in MDA content in maize seedlings. CA induced the anatomical properties under salinity .In present exploration. The cortical cells were induced in root in response to CA than stress. Here, the present study was undertaken with the aim of determining salt induced anatomical and morphological alteration in the presence of exogenous CA. The major reduction in dimension of cortical cells was observed which indicate that salt stress reduced the tolerance of cortical cell more than treatment in maize root. We conclude that CA is a potential phenylpyranoid for protecting crop plant under saline environment.

  20. UPVapor: Cofrentes nuclear power plant production results analysis software

    Energy Technology Data Exchange (ETDEWEB)

    Curiel, M. [Logistica y Acondicionamientos Industriales SAU, Sorolla Center, local 10, Av. de las Cortes Valencianas No. 58, 46015 Valencia (Spain); Palomo, M. J. [ISIRYM, Universidad Politecnica de Valencia, Camino de Vera s/n, Valencia (Spain); Baraza, A. [Iberdrola Generacion S. A., Central Nuclear Cofrentes, Carretera Almansa Requena s/n, 04662 Cofrentes, Valencia (Spain); Vaquer, J., E-mail: m.curiel@lainsa.co [TITANIA Servicios Tecnologicos SL, Sorolla Center, local 10, Av. de las Cortes Valencianas No. 58, 46015 Valencia (Spain)

    2010-10-15

    UPVapor software version 02 has been developed for the Cofrentes nuclear power plant Data Analysis Department (Spain). It is an analysis graphical environment in which users have available all the plant variables registered in the process computer system (SIEC). In order to perform this, UPVapor software has many advanced graphic tools for work simplicity, as well as a friendly environment easy to use and with many configuration possibilities. Plant variables are classified in the same way that they are in SIEC computer and these values are taken from it through the network of Iberdrola. UPVapor can generate two different types of graphics: evolution graphs and X Y graphs. The first ones analyse the evolution up to twenty plant variables in a user's defined time period and according to historic plant files. Many tools are available: cursors, graphic configuration, mobile means, non valid data visualization ... Moreover, a particular analysis configuration can be saved, as a pre selection, giving the possibility of charging pre selection directly and developing quick monitoring of a group of preselected plant variables. In X Y graphs, it is possible to analyse a variable value against another variable in a defined time. As an option, users can filter previous data depending on a variable certain range, with the possibility of programming up to five filters. As well as the other graph, X Y graph has many configurations, saving and printing options. With UPVapor software, data analysts can save a valuable time during daily work and, as it is of easy utilization, it permits to other users to perform their own analysis without ask the analysts to develop. Besides, it can be used from any work centre with access to network framework. (Author)

  1. Towards structural and functional analysis of the plant plasma membrane proton pump

    DEFF Research Database (Denmark)

    Justesen, Bo Højen

    The plasma membrane H+-ATPase is a proton pump essential for several physiological important processes in plants. Through the extrusion of protons from the cell, the PM H+-ATPase establishes and maintains a proton gradient used by proton coupled transporters and secondary active transport......, and regulation of H+-ATPases, key questions, in particular concerning the detailed interaction of regulator proteins with the H+-ATPases, remains answering that may require the use of new approaches. In this work the proton pump Arabidopsis thaliana plasma membrane H+-ATPase isoform 2 has been reconstituted...... into soluble nanoscale lipid bilayers, also termed nanodiscs. Extensive analysis confirms the correct assembly and reconstitution of active proton pump into nanodiscs. The pump inserts as a monomer, which through activity analysis confirms this as the minimal functional unit of the plasma membrane H...

  2. Genomic analysis of plant chromosomes based on meiotic pairing

    Directory of Open Access Journals (Sweden)

    Lisete Chamma Davide

    2007-12-01

    Full Text Available This review presents the principles and applications of classical genomic analysis, with emphasis on plant breeding. The main mathematical models used to estimate the preferential chromosome pairing in diploid or polyploid, interspecific or intergenera hybrids are presented and discussed, with special reference to the applications and studies for the definition of genome relationships among species of the Poaceae family.

  3. Preprocessing and exploratory analysis of chromatographic profiles of plant extracts

    NARCIS (Netherlands)

    Hendriks, M.M.W.B.; Cruz-Juarez, L.; Bont, de D.; Hall, R.D.

    2005-01-01

    The characterization of herbal extracts to compare samples from different origin is important for robust production and quality control strategies. This characterization is now mainly performed by analysis of selected marker compounds. Metabolic fingerprinting of full metabolite profiles of plant ex

  4. Analysis of Waste Isolation Pilot Plant Samples: Integrated Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Britt, Phillip F [ORNL

    2015-03-01

    Analysis of Waste Isolation Pilot Plant Samples: Integrated Summary Report. Summaries of conclusions, analytical processes, and analytical results. Analysis of samples taken from the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico in support of the WIPP Technical Assessment Team (TAT) activities to determine to the extent feasible the mechanisms and chemical reactions that may have resulted in the breach of at least one waste drum and release of waste material in WIPP Panel 7 Room 7 on February 14, 2014. This report integrates and summarizes the results contained in three separate reports, described below, and draws conclusions based on those results. Chemical and Radiochemical Analyses of WIPP Samples R-15 C5 SWB and R16 C-4 Lip; PNNL-24003, Pacific Northwest National Laboratory, December 2014 Analysis of Waste Isolation Pilot Plant (WIPP) Underground and MgO Samples by the Savannah River National Laboratory (SRNL); SRNL-STI-2014-00617; Savannah River National Laboratory, December 2014 Report for WIPP UG Sample #3, R15C5 (9/3/14); LLNL-TR-667015; Lawrence Livermore National Laboratory, January 2015 This report is also contained in the Waste Isolation Pilot Plant Technical Assessment Team Report; SRNL-RP-2015-01198; Savannah River National Laboratory, March 17, 2015, as Appendix C: Analysis Integrated Summary Report.

  5. Comparison of individual and combined effects of salinity and deficit irrigation on physiological, nutritional and ornamental aspects of tolerance in Callistemon laevis plants.

    Science.gov (United States)

    Álvarez, Sara; Sánchez-Blanco, M Jesús

    2015-08-01

    The effect of water deficit, salinity and both applied simultaneously on several physiological and morphological parameters in the ornamental plant Callistemon laevis was studied to identify the tolerance mechanisms developed by this species to these sources of stress and to evaluate their adaptability to such conditions. C. laevis plants were grown in pots outdoors and subjected to four irrigation treatments lasting ten months: control (0.8 dS m(-1), 100% water holding capacity), water deficit (0.8 dS m(-1), 50% of the amount of water supplied in control), saline (4.0 dS m(-1), same amount of water supplied as control) and saline water deficit (4.0 dS m(-1), 50% of the water supplied in the control). Water and saline stress, when applied individually, led to a reduction of 12% and 39% of total biomass, respectively, while overall plant quality (leaf color and flowering) was unaffected. However, saline water deficit affected leaf color and flowering and induced an excessive decrease of growth (68%) due to leaf tissue dehydration and a high leaf Cl and Na concentration. Biomass partitioning depended not only on the amount of water applied, but also on the electrical conductivity of the water. Water stress induced active osmotic adjustment and decreased leaf tissue elasticity. Although both Na and Cl concentrations in the plant tissues increased with salinity, Cl entry through the roots was more restricted. In plants submitted to salinity individually, Na tended to remain in the roots and stems, and little reached the leaves. However, plants simultaneously submitted to water and saline stress were not able to retain this ion in the woody parts. The decrease in stomatal conductance and photosynthesis was more marked in the plants submitted to both stresses, the effect of which decreased photosynthesis, and this together with membrane damage delayed plant recovery. The results show that the combination of deficit irrigation and salinity in C. laevis is not recommended

  6. Potential of Raman and Infrared Spectroscopy for Plant Analysis

    Science.gov (United States)

    Schulz, H.

    2008-11-01

    Various mid-infrared (MIR) and Raman spectroscopic methods applied to the analysis of valuable plant substances or quality parameters in selected horticultural and agricultural crops are presented. Generally, both spectroscopy techniques allow to identify simultaneously characteristic key bands of individual plant components (e.g. carotenoids, alkaloids, polyacetylenes, fatty acids, amino acids, terpenoids). In contrast to MIR methods Raman spectroscopy mostly does not need any sample pre-treatment; even fresh plant material can be analysed without difficulty because water shows only weak Raman scattering properties. In some cases a significant sensivity enhancement of Raman signals can be achieved if the exciting laser wavelength is adjusted to the absorption range of particular plant chromophores such as carotenoids (Resonance Raman effect). Applying FT-IR or FT Raman micro-spectroscopy the distribution of certain plant constituents in the cell wall can be identified without the need for any physical separation. Furthermore it is also possible to analyse secondary metabolites occurring in the cell vacuoles if significant key bands do not coincide with the spectral background of the plant matrix.

  7. Influence of thiourea application on some