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Sample records for water deficit alters

  1. Azospirillum Inoculation Alters Nitrate Reductase Activity and Nitrogen Uptake in Wheat Plant Under Water Deficit Conditions

    OpenAIRE

    N. Aliasgharzad, N. Aliasgharzad; Heydaryan, Zahra; Sarikhani, M.R

    2014-01-01

    Water deficit stress usually diminishes nitrogen uptake by plants. There are evidences that some nitrogen fixing bacteria can alleviate this stress by supplying nitrogen and improving its metabolism in plants. Four Azospirillum strains, A. lipoferum AC45-II, A. brasilense AC46-I, A. irakense AC49-VII and A. irakense AC51-VI were tested for nitrate reductase activity (NRA). In a pot culture experiment using a sandy loam soil, wheat plants (Triticum aestivum L. cv. Sardari) were inoculated with...

  2. Alpha-tocopherol alters endogenous oxidative defense system in mungbean plants under water-deficit condition

    International Nuclear Information System (INIS)

    Sadiq, M.; Akram, N.A.; Javed, M.T.

    2016-01-01

    Foliar spray of plant growth regulating compounds including antioxidants is an effective strategy to overcome the adverse effects of environmental constraints on different plants. A pot experiment was conducted to assess the influence of exogenously applied alpha-tocopherol (Toc) in up-regulating the oxidative defense system in two mungbean cultivars (Cyclone 7008 and Cyclone 8009) grown under normal and water deficit conditions. After 30-day of water deficit treatment, four levels of Toc (0 (non spray), 100, 200 and 300 mg L-1) were applied as a foliage application (at vegetative growth stage). A significant reduction was observed in plant height and total soluble proteins, while an increase was observed in the levels of hydrogen peroxide (H/sub 2/O/sub 2/), ascorbic acid, total phenolics, malondialdehyde (MDA), total free amino acids and the activities of enzymatic (SOD, POD and CAT) antioxidants in both mungbean cultivars under drought conditions. Foliar spray of Toc was effective in improving plant height, AsA, total soluble proteins, total free amino acids, and activities of POD and CAT enzymes, but reduced MDA under water stress conditions. However, no prominent change was observed on the concentrations of H/sub 2/O/sub 2/, phenolics, and SOD enzyme due to foliar-applied Toc in both mungbean cultivars under both water regimes. Both mungbean cultivars were almost similar in all attributes measured except that cv. Cyclone 7008 was higher in the levels of H/sub 2/O/sub 2/ and TSP while cv. Cyclone 8009 in phenolics. So, from the results of this study we can suggest that exogenous application of Toc is effective in improving growth and antioxidative potential of mungbean plants under dry arid environment. (author)

  3. Water deficit alters differentially metabolic pathways affecting important flavor and quality traits in grape berries of Cabernet Sauvignon and Chardonnay

    Science.gov (United States)

    Deluc, Laurent G; Quilici, David R; Decendit, Alain; Grimplet, Jérôme; Wheatley, Matthew D; Schlauch, Karen A; Mérillon, Jean-Michel; Cushman, John C; Cramer, Grant R

    2009-01-01

    Background Water deficit has significant effects on grape berry composition resulting in improved wine quality by the enhancement of color, flavors, or aromas. While some pathways or enzymes affected by water deficit have been identified, little is known about the global effects of water deficit on grape berry metabolism. Results The effects of long-term, seasonal water deficit on berries of Cabernet Sauvignon, a red-wine grape, and Chardonnay, a white-wine grape were analyzed by integrated transcript and metabolite profiling. Over the course of berry development, the steady-state transcript abundance of approximately 6,000 Unigenes differed significantly between the cultivars and the irrigation treatments. Water deficit most affected the phenylpropanoid, ABA, isoprenoid, carotenoid, amino acid and fatty acid metabolic pathways. Targeted metabolites were profiled to confirm putative changes in specific metabolic pathways. Water deficit activated the expression of numerous transcripts associated with glutamate and proline biosynthesis and some committed steps of the phenylpropanoid pathway that increased anthocyanin concentrations in Cabernet Sauvignon. In Chardonnay, water deficit activated parts of the phenylpropanoid, energy, carotenoid and isoprenoid metabolic pathways that contribute to increased concentrations of antheraxanthin, flavonols and aroma volatiles. Water deficit affected the ABA metabolic pathway in both cultivars. Berry ABA concentrations were highly correlated with 9-cis-epoxycarotenoid dioxygenase (NCED1) transcript abundance, whereas the mRNA expression of other NCED genes and ABA catabolic and glycosylation processes were largely unaffected. Water deficit nearly doubled ABA concentrations within berries of Cabernet Sauvignon, whereas it decreased ABA in Chardonnay at véraison and shortly thereafter. Conclusion The metabolic responses of grapes to water deficit varied with the cultivar and fruit pigmentation. Chardonnay berries, which lack any

  4. Water deficit alters differentially metabolic pathways affecting important flavor and quality traits in grape berries of Cabernet Sauvignon and Chardonnay

    Directory of Open Access Journals (Sweden)

    Deluc Laurent G

    2009-05-01

    Full Text Available Abstract Background Water deficit has significant effects on grape berry composition resulting in improved wine quality by the enhancement of color, flavors, or aromas. While some pathways or enzymes affected by water deficit have been identified, little is known about the global effects of water deficit on grape berry metabolism. Results The effects of long-term, seasonal water deficit on berries of Cabernet Sauvignon, a red-wine grape, and Chardonnay, a white-wine grape were analyzed by integrated transcript and metabolite profiling. Over the course of berry development, the steady-state transcript abundance of approximately 6,000 Unigenes differed significantly between the cultivars and the irrigation treatments. Water deficit most affected the phenylpropanoid, ABA, isoprenoid, carotenoid, amino acid and fatty acid metabolic pathways. Targeted metabolites were profiled to confirm putative changes in specific metabolic pathways. Water deficit activated the expression of numerous transcripts associated with glutamate and proline biosynthesis and some committed steps of the phenylpropanoid pathway that increased anthocyanin concentrations in Cabernet Sauvignon. In Chardonnay, water deficit activated parts of the phenylpropanoid, energy, carotenoid and isoprenoid metabolic pathways that contribute to increased concentrations of antheraxanthin, flavonols and aroma volatiles. Water deficit affected the ABA metabolic pathway in both cultivars. Berry ABA concentrations were highly correlated with 9-cis-epoxycarotenoid dioxygenase (NCED1 transcript abundance, whereas the mRNA expression of other NCED genes and ABA catabolic and glycosylation processes were largely unaffected. Water deficit nearly doubled ABA concentrations within berries of Cabernet Sauvignon, whereas it decreased ABA in Chardonnay at véraison and shortly thereafter. Conclusion The metabolic responses of grapes to water deficit varied with the cultivar and fruit pigmentation

  5. Water deficit severity during berry development alters timing of dormancy transitions in wine grape cultivar Malbec

    Science.gov (United States)

    The objective of this study was to test the hypothesis that vine water stress during the growing season can lengthen the dormancy cycle by inducing earlier transition into endodormancy. A bud forcing assay was used to compare the dormancy transitions of field-grown ‘Malbec’ grapevines that had been ...

  6. Alterations in carbon and nitrogen metabolism induced by water deficit in the stems and leaves of Lupinus albus L.

    Science.gov (United States)

    Pinheiro, C; Chaves, M M; Ricardo, C P

    2001-05-01

    Water deficit (WD) in Lupinus albus L. brings about tissue-specific responses that are dependent on stress intensity. Carbohydrate metabolism is very sensitive to changes in plant water status. Six days from withholding water (DAW), sucrose, glucose and fructose levels of the leaf blade had already increased over 5-fold, and the activities of SS and INV(A) had increased c. 1.5-2 times. From 9 DAW on, when stress intensity was more pronounced, these effects were reversed with fructose and glucose concentrations as well as INV(A) activity dropping in parallel. The stem (specifically the stele) responded to the stress intensification with striking increases in the concentration of sugars, N and S, and in the induction of thaumatin-like-protein and an increase in chitinase and peroxidase. At 13 DAW, the plants lost most of the leaves but on rewatering they fully recovered. Thus, the observed changes appear to contribute to a general mechanism of survival under drought, the stem playing a key role in that process.

  7. Increasing Northern Hemisphere water deficit

    Science.gov (United States)

    McCabe, Gregory J.; Wolock, David M.

    2015-01-01

    A monthly water-balance model is used with CRUTS3.1 gridded monthly precipitation and potential evapotranspiration (PET) data to examine changes in global water deficit (PET minus actual evapotranspiration) for the Northern Hemisphere (NH) for the years 1905 through 2009. Results show that NH deficit increased dramatically near the year 2000 during both the cool (October through March) and warm (April through September) seasons. The increase in water deficit near 2000 coincides with a substantial increase in NH temperature and PET. The most pronounced increases in deficit occurred for the latitudinal band from 0 to 40°N. These results indicate that global warming has increased the water deficit in the NH and that the increase since 2000 is unprecedented for the 1905 through 2009 period. Additionally, coincident with the increase in deficit near 2000, mean NH runoff also increased due to increases in P. We explain the apparent contradiction of concurrent increases in deficit and increases in runoff.

  8. Altered brain serotonergic neurotransmission following caffeine withdrawal produces behavioral deficits in rats.

    Science.gov (United States)

    Khaliq, Saima; Haider, Saida; Naqvi, Faizan; Perveen, Tahira; Saleem, Sadia; Haleem, Darakhshan Jabeen

    2012-01-01

    Caffeine administration has been shown to enhance performance and memory in rodents and humans while its withdrawal on the other hand produces neurobehavioral deficits which are thought to be mediated by alterations in monoamines neurotransmission. A role of decreased brain 5-HT (5-hydroxytryptamine, serotonin) levels has been implicated in impaired cognitive performance and depression. Memory functions of rats were assessed by Water Maze (WM) and immobility time by Forced Swim Test (FST). The results of this study showed that repeated caffeine administration for 6 days at 30 mg/kg dose significantly increases brain 5-HT (pcaffeine. Withdrawal of caffeine however produced memory deficits and significantly increases the immobility time of rats in FST. The results of this study are linked with caffeine induced alterations in serotonergic neurotransmission and its role in memory and depression.

  9. Impact of water-deficit stress on tritrophic interactions in a wheat-aphid-parasitoid system.

    Directory of Open Access Journals (Sweden)

    Syed Suhail Ahmed

    Full Text Available Increasing temperature and CO2 concentrations can alter tritrophic interactions in ecosystems, but the impact of increasingly severe drought on such interactions is not well understood. We examined the response of a wheat-aphid-parasitoid system to variation in water-deficit stress levels. Our results showed that arid area clones of the aphid, Sitobion avenae (Fabricius, tended to have longer developmental times compared to semiarid and moist area clones, and the development of S. avenae clones tended to be slower with increasing levels of water-deficit. Body sizes of S. avenae clones from all areas decreased with increasing water-deficit levels, indicating their declining adaptation potential under drought. Compared to arid area clones, moist area clones of S. avenae had a higher frequency of backing under severe water stress only, but a higher frequency of kicking under well-watered conditions only, suggesting a water-deficit level dependent pattern of resistance against the parasitoid, Aphidius gifuensis (Ashmead. The number of S. avenae individuals attacked by the parasitoid in 10 min showed a tendency to decrease with increasing water-deficit levels. Clones of S. avenae tended to have lower parasitism rates under treatments with higher water-deficit levels. The development of the parasitoid tended to be slower under higher levels of water-deficit stress. Thus, the bottom-up effects of water-deficit stressed plants were negative on S. avenae. However, the top-down effects via parasitoids were compromised by water-deficit, which could favor the growth of aphid populations. Overall, the first trophic level under water-deficit stress was shown to have an indirect and negative impact on the third trophic level parasitoid, suggesting that parasitoids could be increasingly vulnerable in future warming scenarios.

  10. Gas exchange alteration caused by water deficit during the bean reproductive stage Alterações das trocas gasosas na fase reprodutiva e produtividade do feijão sob déficit hídrico

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    Lauricio Endres

    2010-01-01

    Full Text Available The purpose of the present study was to analyze gas exchanges in leaves and the parameters of productivity of beans (Phaseolus vulgaris, L. submitted to two water deficiency periods during which three water regimes were employed: W1 (1,0 ETo during the entire plant cycle; W2 (1,0 ETo up to the flowering period and irrigation interruption from the 37 to the 51st day following sowing, and W3 (in addition to the reproductive phase, water deficit was also applied during the vegetative stage. Photosynthesis was one of the main physiological factors affected by water deficit. This was not only caused by the stomata closure, but also by carboxilation reduction due to metabolic damage. This effect was, however, offset 24 h after rehydration. During flowering, the water deficit caused crop productivity to drop significantly, reducing the number of pods and the number of seeds per pod, independently of the water deficit during the vegetative stage. The weight of 100 seeds however, was the same regardless of treatment. These results suggest that the water deficit caused the reduction of photo-assimilates, which affected grain productivity. Nevertheless, once properly formed, seeds developed totally; a strategy of the plant to produce less seeds under stress, but viable to perpetuate the species.Neste trabalho, se analisaram as trocas gasosas das folhas e parâmetros de produtividade de feijão (Phaseolus vulgaris, L. submetido a dois períodos de deficiência hídrica e se empregaram três regimes hídricos, a saber: W1 (1,0 ETo durante todo o ciclo da cultura; W2 (1,0 ETo até a floração e suspensão da irrigação do 37 ao 51º dia após a semeadura (DAS, correspondendo à fase de floração e W3 (além da fase reprodutiva também se aplicou um déficit hídrico durante a fase vegetativa. A fotossíntese foi um dos principais fatores fisiológicos afetados pelo déficit hídrico devido não só ao fechamento estomático, mas, também, à redução da

  11. Effect of progressive water deficit stress on proline accumulation and ...

    African Journals Online (AJOL)

    Water deficit stress is one of the important factors limiting chickpea production in arid and semi-arid regions of West Asia and North Africa. When water deficit stress is imposed, different molecular and biochemical responses take place. This study was carried out to investigate proline accumulation and protein profiles of ...

  12. Genetic variation of response to water deficit in parental genotypes ...

    African Journals Online (AJOL)

    dgomi

    In this study, we investigated morphological and photosynthetic responses to water deficit in parental genotypes of M. ... for adaptation to water deficit in legumes is a prerequisite for any research aiming to improve legume yields. ...... tolerant genotypes in rainfed lowland rice. Field Crop. Res. 99:48-58. Rouached A, Slama I, ...

  13. Altered salience processing in attention deficit hyperactivity disorder.

    Science.gov (United States)

    Tegelbeckers, Jana; Bunzeck, Nico; Duzel, Emrah; Bonath, Björn; Flechtner, Hans-Henning; Krauel, Kerstin

    2015-06-01

    Attentional problems in patients with attention deficit hyperactivity disorder (ADHD) have often been linked with deficits in cognitive control. Whether these deficits are associated with increased sensitivity to external salient stimuli remains unclear. To address this issue, we acquired functional brain images (fMRI) in 38 boys with and without ADHD (age: 11-16 years). To differentiate the effects of item novelty, contextual rareness and task relevance, participants performed a visual oddball task including four stimulus categories: a frequent standard picture (62.5%), unique novel pictures (12.5%), one repeated rare picture (12.5%), and a target picture (12.5%) that required a specific motor response. As a main finding, we can show considerable overlap in novelty-related BOLD responses between both groups, but only healthy participants showed neural deactivation in temporal as well as frontal regions in response to novel pictures. Furthermore, only ADHD patients, but not healthy controls, engaged wide parts of the novelty network when processing the rare but familiar picture. Our results provide first evidence that ADHD patients show enhanced neural activity in response to novel but behaviorally irrelevant stimuli as well as reduced habituation to familiar items. These findings suggest an inefficient use of neuronal resources in children with ADHD that could be closely linked to increased distractibility. © 2015 Wiley Periodicals, Inc.

  14. Altered brain structural networks in attention deficit/hyperactivity disorder children revealed by cortical thickness.

    Science.gov (United States)

    Liu, Tian; Chen, Yanni; Li, Chenxi; Li, Youjun; Wang, Jue

    2017-07-04

    This study investigated the cortical thickness and topological features of human brain anatomical networks related to attention deficit/hyperactivity disorder. Data were collected from 40 attention deficit/hyperactivity disorder children and 40 normal control children. Interregional correlation matrices were established by calculating the correlations of cortical thickness between all pairs of cortical regions (68 regions) of the whole brain. Further thresholds were applied to create binary matrices to construct a series of undirected and unweighted graphs, and global, local, and nodal efficiencies were computed as a function of the network cost. These experimental results revealed abnormal cortical thickness and correlations in attention deficit/hyperactivity disorder, and showed that the brain structural networks of attention deficit/hyperactivity disorder subjects had inefficient small-world topological features. Furthermore, their topological properties were altered abnormally. In particular, decreased global efficiency combined with increased local efficiency in attention deficit/hyperactivity disorder children led to a disorder-related shift of the network topological structure toward regular networks. In addition, nodal efficiency, cortical thickness, and correlation analyses revealed that several brain regions were altered in attention deficit/hyperactivity disorder patients. These findings are in accordance with a hypothesis of dysfunctional integration and segregation of the brain in patients with attention deficit/hyperactivity disorder and provide further evidence of brain dysfunction in attention deficit/hyperactivity disorder patients by observing cortical thickness on magnetic resonance imaging.

  15. Water deficit increases stilbene metabolism in Cabernet Sauvignon berries.

    Science.gov (United States)

    Deluc, Laurent G; Decendit, Alain; Papastamoulis, Yorgos; Mérillon, Jean-Michel; Cushman, John C; Cramer, Grant R

    2011-01-12

    The impact of water deficit on stilbene biosynthesis in wine grape (Vitis vinifera) berries was investigated. Water deficit increased the accumulation of trans-piceid (the glycosylated form of resveratrol) by 5-fold in Cabernet Sauvignon berries but not in Chardonnay. Similarly, water deficit significantly increased the transcript abundance of genes involved in the biosynthesis of stilbene precursors in Cabernet Sauvignon. Increased expression of stilbene synthase, but not that of resveratrol-O-glycosyltransferase, resulted in increased trans-piceid concentrations. In contrast, the transcript abundance of the same genes declined in Chardonnay in response to water deficit. Twelve single nucleotide polymorphisms (SNPs) were identified in the promoters of stilbene synthase genes of Cabernet Sauvignon, Chardonnay, and Pinot Noir. These polymorphisms resulted in eight changes within the predicted cis regulatory elements in Cabernet Sauvignon and Chardonnay. These results suggest that cultivar-specific molecular mechanisms might exist that control resveratrol biosynthesis in grapes.

  16. Effect of water deficit stress on proline contents, soluble sugars ...

    African Journals Online (AJOL)

    Effect of water deficit stress on proline contents, soluble sugars, chlorophyll and grain yield of sunflower ... Journal Home > Vol 11, No 1 (2012) > ... The objective of the present work was to determine the mechanisms of tolerance of four ...

  17. GABA Neuron Alterations, Cortical Circuit Dysfunction and Cognitive Deficits in Schizophrenia

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    Guillermo Gonzalez-Burgos

    2011-01-01

    Full Text Available Schizophrenia is a brain disorder associated with cognitive deficits that severely affect the patients' capacity for daily functioning. Whereas our understanding of its pathophysiology is limited, postmortem studies suggest that schizophrenia is associated with deficits of GABA-mediated synaptic transmission. A major role of GABA-mediated transmission may be producing synchronized network oscillations which are currently hypothesized to be essential for normal cognitive function. Therefore, cognitive deficits in schizophrenia may result from a GABA synapse dysfunction that disturbs neural synchrony. Here, we highlight recent studies further suggesting alterations of GABA transmission and network oscillations in schizophrenia. We also review current models for the mechanisms of GABA-mediated synchronization of neural activity, focusing on parvalbumin-positive GABA neurons, which are altered in schizophrenia and whose function has been strongly linked to the production of neural synchrony. Alterations of GABA signaling that impair gamma oscillations and, as a result, cognitive function suggest paths for novel therapeutic interventions.

  18. GABA neuron alterations, cortical circuit dysfunction and cognitive deficits in schizophrenia.

    Science.gov (United States)

    Gonzalez-Burgos, Guillermo; Fish, Kenneth N; Lewis, David A

    2011-01-01

    Schizophrenia is a brain disorder associated with cognitive deficits that severely affect the patients' capacity for daily functioning. Whereas our understanding of its pathophysiology is limited, postmortem studies suggest that schizophrenia is associated with deficits of GABA-mediated synaptic transmission. A major role of GABA-mediated transmission may be producing synchronized network oscillations which are currently hypothesized to be essential for normal cognitive function. Therefore, cognitive deficits in schizophrenia may result from a GABA synapse dysfunction that disturbs neural synchrony. Here, we highlight recent studies further suggesting alterations of GABA transmission and network oscillations in schizophrenia. We also review current models for the mechanisms of GABA-mediated synchronization of neural activity, focusing on parvalbumin-positive GABA neurons, which are altered in schizophrenia and whose function has been strongly linked to the production of neural synchrony. Alterations of GABA signaling that impair gamma oscillations and, as a result, cognitive function suggest paths for novel therapeutic interventions.

  19. Water deficit modifies the carbon isotopic composition of lipids, soluble sugars and leaves of Copaifera langsdorffii Desf. (Fabaceae

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    Angelo Albano da Silva Bertholdi

    2017-11-01

    Full Text Available ABSTRACT Water deficit is most frequent in forest physiognomies subjected to climate change. As a consequence, several tree species alter tissue water potential, gas exchange and production of carbon compounds to overcome damage caused by water deficiency. The working hypothesis, that a reduction in gas exchange by plants experiencing water deficit will affect the composition of carbon compounds in soluble sugars, lipids and vegetative structures, was tested on Copaifera langsdorffii. Stomatal conductance, leaf water potential, and CO2 assimilation rate declined after a period of water deficit. After rehydration, leaf water potential and leaf gas exchange did not recover completely. Water deficit resulted in 13C enrichment in leaves, soluble sugars and root lipids. Furthermore, the amount of soluble sugars and root lipids decreased after water deficit. In rehydration, the carbon isotopic composition and amount of root lipids returned to levels similar to the control. Under water deficit, 13C-enriched in root lipids assists in the adjustment of cellular membrane turgidity and avoids damage to the process of water absorption by roots. These physiological adjustments permit a better understanding of the responses of Copaifera langsdorffi to water deficit.

  20. Differential response to water deficit stress in alfalfa ( Medicago ...

    African Journals Online (AJOL)

    The present study was fixed as objective to compare the response to water deficit (33% of field capacity, FC) stress of eight cultivars of Medicago sativa, originating from the Mediterranean basin. Comparison was performed on some key parameters such as growth, relative water content, leaf water potential, MDA tissue ...

  1. Altered White Matter Microstructure in Children with Attention-Deficit/Hyperactivity Disorder

    Science.gov (United States)

    Nagel, Bonnie J.; Bathula, Deepti; Herting, Megan; Schmitt, Colleen; Kroenke, Christopher D.; Fair, Damien; Nigg, Joel T.

    2011-01-01

    Objective: Identification of biomarkers is a priority for attention-deficit/hyperactivity disorder (ADHD). Studies have documented macrostructural brain alterations in ADHD, but few have examined white matter microstructure, particularly in preadolescent children. Given dramatic white matter maturation across childhood, microstructural differences…

  2. Deficit irrigation of peach trees to reduce water consumption

    Science.gov (United States)

    Lack of water is a major limiting factor for production tree fruits such as peaches in the San Joaquin Valley of California and many other arid- or semi-arid regions in the world. Deficit irrigation can be used in some cropping systems as a water resource management strategy to reduce non-productiv...

  3. Transcriptome profiling of tobacco under water deficit conditions

    Directory of Open Access Journals (Sweden)

    Roel C. Rabara

    2015-09-01

    Full Text Available Drought is one of the limiting environmental factors that affect crop production. Understanding the molecular basis of how plants respond to this water deficit stress is key to developing drought tolerant crops. In this study we generated time course-based transcriptome profiles of tobacco plants under water deficit conditions using microarray technology. In this paper, we describe in detail the experimental procedures and analyses performed in our study. The data set we generated (available in the NCBI/GEO database under GSE67434 has been analysed to identify genes that are involved in the regulation of tobacco's responses to drought.

  4. Altered Kinematics of Facial Emotion Expression and Emotion Recognition Deficits Are Unrelated in Parkinson's Disease.

    Science.gov (United States)

    Bologna, Matteo; Berardelli, Isabella; Paparella, Giulia; Marsili, Luca; Ricciardi, Lucia; Fabbrini, Giovanni; Berardelli, Alfredo

    2016-01-01

    Altered emotional processing, including reduced emotion facial expression and defective emotion recognition, has been reported in patients with Parkinson's disease (PD). However, few studies have objectively investigated facial expression abnormalities in PD using neurophysiological techniques. It is not known whether altered facial expression and recognition in PD are related. To investigate possible deficits in facial emotion expression and emotion recognition and their relationship, if any, in patients with PD. Eighteen patients with PD and 16 healthy controls were enrolled in this study. Facial expressions of emotion were recorded using a 3D optoelectronic system and analyzed using the facial action coding system. Possible deficits in emotion recognition were assessed using the Ekman test. Participants were assessed in one experimental session. Possible relationship between the kinematic variables of facial emotion expression, the Ekman test scores, and clinical and demographic data in patients were evaluated using the Spearman's test and multiple regression analysis. The facial expression of all six basic emotions had slower velocity and lower amplitude in patients in comparison to healthy controls (all P s facial expression kinematics and emotion recognition deficits were unrelated in patients (all P s > 0.05). Finally, no relationship emerged between kinematic variables of facial emotion expression, the Ekman test scores, and clinical and demographic data in patients (all P s > 0.05). The results in this study provide further evidence of altered emotional processing in PD. The lack of any correlation between altered facial emotion expression kinematics and emotion recognition deficits in patients suggests that these abnormalities are mediated by separate pathophysiological mechanisms.

  5. Effect of water deficit on growth and photosynthetic characteristics of ...

    African Journals Online (AJOL)

    Water deficit decreased total leaf area, above-ground biomass, net photosynthesis, stomatal conductance, internal CO2 concentration and the actual quantum yield of PS II electron transport relative to cultivars that were grown under control condition. Measurement of stomatal conductance provided useful information to ...

  6. Soybean response to nitrogen fertilizer under water deficit conditions

    African Journals Online (AJOL)

    user

    2011-04-18

    Apr 18, 2011 ... In order to determine the effect of water deficit and nitrogen fertilizer application on growth indices, yield and yield ... located in 39°N and 47°E longitude and has 32 m altitude. The soil ...... Stable Isotope Research (GASIR).

  7. Ascorbic acid ameliorates behavioural deficits and neuropathological alterations in rat model of Alzheimer's disease.

    Science.gov (United States)

    Olajide, Olayemi Joseph; Yawson, Emmanuel Olusola; Gbadamosi, Ismail Temitayo; Arogundade, Tolulope Timothy; Lambe, Ezra; Obasi, Kosisochukwu; Lawal, Ismail Tayo; Ibrahim, Abdulmumin; Ogunrinola, Kehinde Yomi

    2017-03-01

    Exploring the links between neural pathobiology and behavioural deficits in Alzheimer's disease (AD), and investigating substances with known therapeutic advantages over subcellular mechanisms underlying these dysfunctions could advance the development of potent therapeutic molecules for AD treatment. Here we investigated the efficacy of ascorbic acid (AA) in reversing aluminium chloride (AlCl 3 )-induced behavioural deficits and neurotoxic cascades within prefrontal cortex (PFC) and hippocampus of rats. A group of rats administered oral AlCl 3 (100mg/kg) daily for 15days showed degenerative changes characterised by significant weight loss, reduced exploratory/working memory, frontal-dependent motor deficits, cognitive decline, memory dysfunction and anxiety during behavioural assessments compared to control. Subsequent analysis showed that oxidative impairment-indicated by depleted superoxide dismutase and lipid peroxidation (related to glutathione-S-transferase activity), cholinergic deficits seen by increased neural acetylcholinesterase (AChE) expression and elevated lactate dehydrogenase underlie behavioural alterations. Furthermore, evidences of proteolysis were seen by reduced Nissl profiles in neuronal axons and dendrites which correspond to apoptotic changes observed in H&E staining of PFC and hippocampal sections. Interestingly, AA (100mg/kg daily for 15days) significantly attenuated behavioural deficits in rats through inhibition of molecular and cellular stressor proteins activated by AlCl 3. Our results showed that the primary mechanisms underlying AA therapeutic advantages relates closely with its abilities to scavenge free radicals, prevent membrane lipid peroxidation, modulate neuronal bioenergetics, act as AChE inhibitor and through its anti-proteolytic properties. These findings suggest that supplementing endogenous AA capacity through its pharmacological intake may inhibit progression of AD-related neurodegenerative processes and behavioural

  8. Alterações no perfil de frações nitrogenadas em calos de cana-de-açúcar induzidas por deficit hídrico Alterations on the profile of nitrogenous fractions in sugarcane calluses induced by water deficit

    Directory of Open Access Journals (Sweden)

    Lucila Karla Felix Lima de Brito

    2008-06-01

    Full Text Available O objetivo deste trabalho foi avaliar o uso de marcadores bioquímicos e fisiológicos, na caracterização do estresse hídrico em calos de cultivares de cana-de-açúcar (Sacharum sp., RB 72 454 (sensível e SP 813250 (resistente, contrastantes quanto à resistência à seca em campo. O delineamento experimental foi o inteiramente casualizado, em esquema fatorial de 2x5 [cultivar x doses de polietilenoglicol (PEG], com dez tratamentos e três repetições. Os calos foram submetidos a concentrações de PEG correspondentes aos potenciais osmóticos de 0, -0,3, -0,6, -0,9 e -1,2 MPa, por 120 horas. A variação no conteúdo relativo de água e na umidade não foi significativamente diferente entre as cultivares. Entretanto, foi observada a tendência de aumento no vazamento de eletrólitos, em conseqüência da diminuição do potencial osmótico na cultivar tolerante. Na cultivar sensível, observou-se tendência de aumento de prolina e, na resistente, diminuição, embora os níveis não tenham sido afetados pelo deficit hídrico. As concentrações de aminoácidos livres foram maiores na sensível. Houve queda nas concentrações de amônia, em ambas cultivares. Os níveis de proteínas não foram afetados pelo PEG. O perfil protéico por SDS-PAGE não mostrou aumento induzido por PEG, na intensidade das bandas correspondentes aos peptídeos entre 14 e 66 kDa. Os marcadores bioquímicos e fisiológicos não foram relacionados ao grau diferencial de resistência observado nas cultivares em condições de campo.The aim of this work was to evaluate the use of physiological and biochemical parameters, in the characterization of water stress in sugarcane (Sacharum sp. calluses, cultivars RB 72454 (sensible and SP 813250 (resistant, differing in drought resistance in the field. The experimental design was completely randomized with a factorial scheme 2x5 [cultivar x concentrations of polyethylene glycol (PEG], with ten treatments and three

  9. Daytime soybean transcriptome fluctuations during water deficit stress.

    Science.gov (United States)

    Rodrigues, Fabiana Aparecida; Fuganti-Pagliarini, Renata; Marcolino-Gomes, Juliana; Nakayama, Thiago Jonas; Molinari, Hugo Bruno Correa; Lobo, Francisco Pereira; Harmon, Frank G; Nepomuceno, Alexandre Lima

    2015-07-07

    Since drought can seriously affect plant growth and development and little is known about how the oscillations of gene expression during the drought stress-acclimation response in soybean is affected, we applied Illumina technology to sequence 36 cDNA libraries synthesized from control and drought-stressed soybean plants to verify the dynamic changes in gene expression during a 24-h time course. Cycling variables were measured from the expression data to determine the putative circadian rhythm regulation of gene expression. We identified 4866 genes differentially expressed in soybean plants in response to water deficit. Of these genes, 3715 were differentially expressed during the light period, from which approximately 9.55% were observed in both light and darkness. We found 887 genes that were either up- or down-regulated in different periods of the day. Of 54,175 predicted soybean genes, 35.52% exhibited expression oscillations in a 24 h period. This number increased to 39.23% when plants were submitted to water deficit. Major differences in gene expression were observed in the control plants from late day (ZT16) until predawn (ZT20) periods, indicating that gene expression oscillates during the course of 24 h in normal development. Under water deficit, dissimilarity increased in all time-periods, indicating that the applied stress influenced gene expression. Such differences in plants under stress were primarily observed in ZT0 (early morning) to ZT8 (late day) and also from ZT4 to ZT12. Stress-related pathways were triggered in response to water deficit primarily during midday, when more genes were up-regulated compared to early morning. Additionally, genes known to be involved in secondary metabolism and hormone signaling were also expressed in the dark period. Gene expression networks can be dynamically shaped to acclimate plant metabolism under environmental stressful conditions. We have identified putative cycling genes that are expressed in soybean leaves

  10. Altered neural connectivity during response inhibition in adolescents with attention-deficit/hyperactivity disorder and their unaffected siblings

    NARCIS (Netherlands)

    van Rooij, Daan; Hartman, Catharina A.; Mennes, Maarten; Oosterlaan, Jaap; Franke, Barbara; Rommelse, Nanda; Heslenfeld, Dirk; Faraone, Stephen V.; Buitelaar, Jan K.; Hoekstra, Pieter J.

    2015-01-01

    Introduction: Response inhibition is one of the executive functions impaired in attention-deficit/hyperactivity disorder (ADHD). Increasing evidence indicates that altered functional and structural neural connectivity are part of the neurobiological basis of ADHD. Here, we investigated if

  11. Microstructural white matter alterations and hippocampal volumes are associated with cognitive deficits in craniopharyngioma.

    Science.gov (United States)

    Fjalldal, S; Follin, C; Svärd, D; Rylander, L; Gabery, S; Petersén, Å; van Westen, D; Sundgren, P C; Björkman-Burtscher, I M; Lätt, J; Ekman, B; Johanson, A; Erfurth, E M

    2018-06-01

    Patients with craniopharyngioma (CP) and hypothalamic lesions (HL) have cognitive deficits. Which neural pathways are affected is unknown. To determine whether there is a relationship between microstructural white matter (WM) alterations detected with diffusion tensor imaging (DTI) and cognition in adults with childhood-onset CP. A cross-sectional study with a median follow-up time of 22 (6-49) years after operation. The South Medical Region of Sweden (2.5 million inhabitants). Included were 41 patients (24 women, ≥17 years) surgically treated for childhood-onset CP between 1958-2010 and 32 controls with similar age and gender distributions. HL was found in 23 patients. Subjects performed cognitive tests and magnetic resonance imaging, and images were analyzed using DTI of uncinate fasciculus, fornix, cingulum, hippocampus and hypothalamus as well as hippocampal volumetry. Right uncinate fasciculus was significantly altered ( P  ≤ 0.01). Microstructural WM alterations in left ventral cingulum were significantly associated with worse performance in visual episodic memory, explaining approximately 50% of the variation. Alterations in dorsal cingulum were associated with worse performance in immediate, delayed recall and recognition, explaining 26-38% of the variation, and with visuospatial ability and executive function, explaining 19-29%. Patients who had smaller hippocampal volume had worse general knowledge ( P  = 0.028), and microstructural WM alterations in hippocampus were associated with a decline in general knowledge and episodic visual memory. A structure to function relationship is suggested between microstructural WM alterations in cingulum and in hippocampus with cognitive deficits in CP. © 2018 The authors.

  12. Water deficit mapping of soils in Southern and Insular Italy

    Energy Technology Data Exchange (ETDEWEB)

    Ciavatta, C; Vianello, G

    1987-03-01

    Cross-elaboration of climatic, pedological and vegetational factors allows the water balance of soils to be defined. The data obtained are of particular interest not only for the primary sector, but also for the economy as a whole since the availability of such information is necessary for the correct and rational use of water resources. The application of a methodology, which takes into account the previously mentioned factors, led to the realization of a map showing the overall, annual and monthly water deficit of the soils in Southern Italy, Sicily and Sardinia.

  13. Water deficit stress-induced changes in carbon and nitrogen partitioning in Chenopodium quinoa Willd.

    Science.gov (United States)

    Bascuñán-Godoy, Luisa; Reguera, Maria; Abdel-Tawab, Yasser M; Blumwald, Eduardo

    2016-03-01

    Water deficit stress followed by re-watering during grain filling resulted in the induction of the ornithine pathway and in changes in Quinoa grain quality. The genetic diversity of Chenopodium quinoa Willd. (Quinoa) is accompanied by an outstanding environmental adaptability and high nutritional properties of the grains. However, little is known about the biochemical and physiological mechanisms associated with the abiotic stress tolerance of Quinoa. Here, we characterized carbon and nitrogen metabolic changes in Quinoa leaves and grains in response to water deficit stress analyzing their impact on the grain quality of two lowland ecotypes (Faro and BO78). Differences in the stress recovery response were found between genotypes including changes in the activity of nitrogen assimilation-associated enzymes that resulted in differences in grain quality. Both genotypes showed a common strategy to overcome water stress including the stress-induced synthesis of reactive oxygen species scavengers and osmolytes. Particularly, water deficit stress induced the stimulation of the ornithine and raffinose pathways. Our results would suggest that the regulation of C- and N partitioning in Quinoa during grain filling could be used for the improvement of the grain quality without altering grain yields.

  14. Perfusion deficits and functional connectivity alterations in patients with post-traumatic stress disorder

    Science.gov (United States)

    Liu, Yang; Li, Baojuan; Zhang, Xi; Zhang, Linchuan; Li, Liang; Lu, Hongbing

    2016-03-01

    To explore the alteration in cerebral blood flow (CBF) and functional connectivity between survivors with recent onset post-traumatic stress disorder (PTSD) and without PTSD, survived from the same coal mine flood disaster. In this study, a processing pipeline using arterial spin labeling (ASL) sequence was proposed. Considering low spatial resolution of ASL sequence, a linear regression method was firstly used to correct the partial volume (PV) effect for better CBF estimation. Then the alterations of CBF between two groups were analyzed using both uncorrected and PV-corrected CBF maps. Based on altered CBF regions detected from the CBF analysis as seed regions, the functional connectivity abnormities in PTSD patients was investigated. The CBF analysis using PV-corrected maps indicates CBF deficits in the bilateral frontal lobe, right superior frontal gyrus and right corpus callosum of PTSD patients, while only right corpus callosum was identified in uncorrected CBF analysis. Furthermore, the regional CBF of the right superior frontal gyrus exhibits significantly negative correlation with the symptom severity in PTSD patients. The resting-state functional connectivity indicates increased connectivity between left frontal lobe and right parietal lobe. These results indicate that PV-corrected CBF exhibits more subtle perfusion changes and may benefit further perfusion and connectivity analysis. The symptom-specific perfusion deficits and aberrant connectivity in above memory-related regions may be putative biomarkers for recent onset PTSD induced by a single prolonged trauma exposure and help predict the severity of PTSD.

  15. Regulated deficit irrigation alters anthocyanins, tannins and sensory properties of cabernet sauvignon grapes and wines.

    Science.gov (United States)

    Casassa, Luis Federico; Keller, Markus; Harbertson, James F

    2015-04-29

    Four regulated deficit irrigation (RDI) regimes were applied to Cabernet Sauvignon grapes, which were analyzed for phenolics and also made into wine over three consecutive growing seasons. Relative to an industry standard regime (IS), yield was reduced over the three years by 37% in a full-deficit (FD) regime and by 18% in an early deficit (ED) regime, whereas no yield reduction occurred with a late deficit (LD) regime. Relative to IS, skin anthocyanin concentration (fresh weight basis) was 18% and 24% higher in ED and FD, respectively, whereas no effect was seen in LD. Seed tannin concentration was 3% and 8% higher in ED and FD, respectively, relative to the other two RDI regimes, whereas seed tannin content (amount per berry) was higher in IS than in FD. There were no practically relevant effects on the basic chemistry of the wines. The finished wines showed concentrations of tannins and anthocyanins that generally mirrored observed differences in skin and seed phenolic concentrations, although these were amplified in FD wines. Descriptive sensory analysis of the 2008 wines showed that FD wines were the most saturated in color, with higher purple hue, roughness, dryness and harshness, followed by ED wines, whereas IS and LD wines were less saturated in color and with higher brown and red hues. Overall, FD and ED seemed to yield fruit and wine with greater concentrations of phenolics than IS and LD, with the additional advantage of reducing water usage. However, these apparent benefits need to be balanced out with reductions in crop yields and potential long-term effects associated with pre-véraison water deficits.

  16. Regulated Deficit Irrigation Alters Anthocyanins, Tannins and Sensory Properties of Cabernet Sauvignon Grapes and Wines

    Directory of Open Access Journals (Sweden)

    Luis Federico Casassa

    2015-04-01

    Full Text Available Four regulated deficit irrigation (RDI regimes were applied to Cabernet Sauvignon grapes, which were analyzed for phenolics and also made into wine over three consecutive growing seasons. Relative to an industry standard regime (IS, yield was reduced over the three years by 37% in a full-deficit (FD regime and by 18% in an early deficit (ED regime, whereas no yield reduction occurred with a late deficit (LD regime. Relative to IS, skin anthocyanin concentration (fresh weight basis was 18% and 24% higher in ED and FD, respectively, whereas no effect was seen in LD. Seed tannin concentration was 3% and 8% higher in ED and FD, respectively, relative to the other two RDI regimes, whereas seed tannin content (amount per berry was higher in IS than in FD. There were no practically relevant effects on the basic chemistry of the wines. The finished wines showed concentrations of tannins and anthocyanins that generally mirrored observed differences in skin and seed phenolic concentrations, although these were amplified in FD wines. Descriptive sensory analysis of the 2008 wines showed that FD wines were the most saturated in color, with higher purple hue, roughness, dryness and harshness, followed by ED wines, whereas IS and LD wines were less saturated in color and with higher brown and red hues. Overall, FD and ED seemed to yield fruit and wine with greater concentrations of phenolics than IS and LD, with the additional advantage of reducing water usage. However, these apparent benefits need to be balanced out with reductions in crop yields and potential long-term effects associated with pre-véraison water deficits.

  17. Interact to survive: Phyllobacterium brassicacearum improves Arabidopsis tolerance to severe water deficit and growth recovery.

    Directory of Open Access Journals (Sweden)

    Justine Bresson

    Full Text Available Mutualistic bacteria can alter plant phenotypes and confer new abilities to plants. Some plant growth-promoting rhizobacteria (PGPR are known to improve both plant growth and tolerance to multiple stresses, including drought, but reports on their effects on plant survival under severe water deficits are scarce. We investigated the effect of Phyllobacterium brassicacearum STM196 strain, a PGPR isolated from the rhizosphere of oilseed rape, on survival, growth and physiological responses of Arabidopsis thaliana to severe water deficits combining destructive and non-destructive high-throughput phenotyping. Soil inoculation with STM196 greatly increased the survival rate of A. thaliana under several scenarios of severe water deficit. Photosystem II efficiency, assessed at the whole-plant level by high-throughput fluorescence imaging (Fv/Fm, was related to the probability of survival and revealed that STM196 delayed plant mortality. Inoculated surviving plants tolerated more damages to the photosynthetic tissues through a delayed dehydration and a better tolerance to low water status. Importantly, STM196 allowed a better recovery of plant growth after rewatering and stressed plants reached a similar biomass at flowering than non-stressed plants. Our results highlight the importance of plant-bacteria interactions in plant responses to severe drought and provide a new avenue of investigations to improve drought tolerance in agriculture.

  18. Water deficit imposed by deficit irrigation at different plant growth stages of maize

    International Nuclear Information System (INIS)

    Calvache, M.; Reichardt, C.

    1995-01-01

    The purpose of this study was to identify specific growth stages of maize Crop, at which the plant is less sensitive to water stress so that irrigation can be omitted withhout significant decrease yield. The field experiment was conducted at a University experiment station, Tumbaco, Pichincha, Ecuador, during may - october 1993, on a sandy loam soil ( typic durustoll). Soil moisture was monitored with a neutron probe down to 0.70 m depth, before and 24 h after each irrigation. The actual evapotranspiration of the crop was estimated by the water - balance technique. Field water efficiency and crop water use efficiency were calculated by dividing actual grain yield by irrigation and by ETa, respectively. Nitrogen fertilizer use efficiency was calculated using N - 15 methodology in the 75 kg N/ ha treatment. From the yield data, it can be concluded that treatments which had irrigation deficit had lower yield than those that had suplementary irrigation. The flowering and yield formation stages were the most sensitive to moisture stress. Nitrogen fertilization significantly increased the grain yield. The crop water use effeciency was the lowest at the flowering and yield formation of the region, the treatments I1 and I7 had the same crop water use efficiency. The results of N - 15 labelled plots ( F1) showed that soil water deficiency significantly affects nitrogen was derived from fertilizer in treatments I3 and I7 and only 11 - 9% in the treatments I2 and I5 respectively. ( Author)

  19. Olanzapine Reverses MK-801-Induced Cognitive Deficits and Region-Specific Alterations of NMDA Receptor Subunits

    Science.gov (United States)

    Liu, Xiao; Li, Jitao; Guo, Chunmei; Wang, Hongli; Sun, Yaxin; Wang, Han; Su, Yun-Ai; Li, Keqing; Si, Tianmei

    2018-01-01

    Cognitive dysfunction constitutes an essential component in schizophrenia for its early presence in the pathophysiology of the disease and close relatedness to life quality of patients. To develop effective treatment of cognitive deficits, it is important to understand their neurobiological causes and to identify potential therapeutic targets. In this study, adopting repeated MK-801 treatment as an animal model of schizophrenia, we investigated whether antipsychotic drugs, olanzapine and haloperidol, can reverse MK-801-induced cognitive deficits and how the reversal processes recruited proteins involved in glutamate neurotransmission in rat medial prefrontal cortex (mPFC) and hippocampus. We found that low-dose chronic MK-801 treatment impaired object-in-context recognition memory and reversal learning in the Morris water maze, leaving reference memory relatively unaffected, and that these cognitive deficits can be partially reversed by olanzapine, not haloperidol, treatment. At the molecular level, chronic MK-801 treatment resulted in the reduction of multiple N-methyl-D-aspartate (NMDA) receptor subunits in rat mPFC and olanzapine, not haloperidol, treatment restored the levels of GluN1 and phosphorylated GluN2B in this region. Taken together, MK-801-induced cognitive deficits may be associated with region-specific changes in NMDA receptor subunits and the reversal of specific NMDA receptor subunits may underlie the cognition-enhancing effects of olanzapine. PMID:29375333

  20. Differential motor alterations in children with three types of attention deficit hyperactivity disorder

    Directory of Open Access Journals (Sweden)

    Adrián Poblano

    2014-11-01

    Full Text Available Objective To determine frequency of motor alterations in children with attention deficit hyperactivity disorder (ADHD. Method We evaluated 19 children aged 7-12 years with ADHD classified in three sub-types: Combined (ADHD-C, with Inattention (ADHD-I, and with Hyperactivity (ADHD-H. Controls were age- and gender matched healthy children. We utilized Bruininks-Oseretsky Test of Motor Proficiency (BOTMP for measuring motor skills. Results We observed differences between children with ADHD and controls in BOTMP general score and in static coordination, dynamic general- and hand- coordination, and in synkinetic movements. We also found differences in dynamic hand coordination between controls and children with ADHD-C; in dynamic general coordination between controls and children with ADHD-H; and in frequency of synkinetic movements between controls and children with ADHD-H. Conclusion Children with ADHD with a major degree of hyperactivity showed greater frequency of motor alterations.

  1. Neuroanatomic alterations and social and communication deficits in monozygotic twins discordant for autism disorder.

    Science.gov (United States)

    Mitchell, Shanti R; Reiss, Allan L; Tatusko, Danielle H; Ikuta, Ichiro; Kazmerski, Dana B; Botti, Jo-Anna C; Burnette, Courtney P; Kates, Wendy R

    2009-08-01

    Investigating neuroanatomic differences in monozygotic twins who are discordant for autism can help unravel the relative contributions of genetics and environment to this pervasive developmental disorder. The authors used magnetic resonance imaging (MRI) to investigate several brain regions of interest in monozygotic twins who varied in degree of phenotypic discordance for narrowly defined autism. The subjects were 14 pairs of monozygotic twins between the ages of 5 and 14 years old and 14 singleton age- and gender-matched typically developing comparison subjects. The monozygotic twin group was a cohort of children with narrowly defined autistic deficits and their co-twins who presented with varying levels of autistic deficits. High-resolution MRIs were acquired and volumetric/area measurements obtained for the frontal lobe, amygdala, and hippocampus and subregions of the prefrontal cortex, corpus callosum, and cerebellar vermis. No neurovolumetric/area differences were found between twin pairs. Relative to typically developing comparison subjects, dorsolateral prefrontal cortex volumes and anterior areas of the corpus callosum were significantly altered in autistic twins, and volumes of the posterior vermis were altered in both autistic twins and co-twins. Intraclass correlation analysis of brain volumes between children with autism and their co-twins indicated that the degree of within-pair neuroanatomic concordance varied with brain region. In the group of subjects with narrowly defined autism only, dorsolateral prefrontal cortex, amygdala, and posterior vermis volumes were significantly associated with the severity of autism based on scores from the Autism Diagnostic Observation Schedule-Generic. These findings support previous research demonstrating alterations in the prefrontal cortex, corpus callosum, and posterior vermis in children with autism and further suggest that alterations are associated with the severity of the autism phenotype. Continued research

  2. Plant genetic and molecular responses to water deficit

    Directory of Open Access Journals (Sweden)

    Silvio Salvi

    2011-02-01

    Full Text Available Plant productivity is severely affected by unfavourable environmental conditions (biotic and abiotic stresses. Among others, water deficit is the plant stress condition which mostly limits the quality and the quantity of plant products. Tolerance to water deficit is a polygenic trait strictly dependent on the coordinated expression of a large set of genes coding for proteins directly involved in stress-induced protection/repair mechanisms (dehydrins, chaperonins, enzymes for the synthesis of osmoprotectants and detoxifying compounds, and others as well as genes involved in transducing the stress signal and regulating gene expression (transcription factors, kinases, phosphatases. Recently, research activities in the field evolved from the study of single genes directly involved in cellular stress tolerance (functional genes to the identification and characterization of key regulatory genes involved in stress perception and transduction and able to rapidly and efficiently activate the complex gene network involved in the response to stress. The complexity of the events occurring in response to stress have been recently approached by genomics tools; in fact the analysis of transcriptome, proteome and metabolome of a plant tissue/cell in response to stress already allowed to have a global view of the cellular and molecular events occurring in response to water deficit, by the identification of genes activated and co-regulated by the stress conditions and the characterization of new signalling pathways. Moreover the recent application of forward and reverse genetic approaches, trough mutant collection development, screening and characterization, is giving a tremendous impulse to the identification of gene functions with key role in stress tolerance. The integration of data obtained by high-throughput genomic approaches, by means of powerful informatic tools, is allowing nowadays to rapidly identify of major genes/QTLs involved in stress tolerance

  3. Sociability Deficits and Altered Amygdala Circuits in Mice Lacking Pcdh10, an Autism Associated Gene.

    Science.gov (United States)

    Schoch, Hannah; Kreibich, Arati S; Ferri, Sarah L; White, Rachel S; Bohorquez, Dominique; Banerjee, Anamika; Port, Russell G; Dow, Holly C; Cordero, Lucero; Pallathra, Ashley A; Kim, Hyong; Li, Hongzhe; Bilker, Warren B; Hirano, Shinji; Schultz, Robert T; Borgmann-Winter, Karin; Hahn, Chang-Gyu; Feldmeyer, Dirk; Carlson, Gregory C; Abel, Ted; Brodkin, Edward S

    2017-02-01

    Behavioral symptoms in individuals with autism spectrum disorder (ASD) have been attributed to abnormal neuronal connectivity, but the molecular bases of these behavioral and brain phenotypes are largely unknown. Human genetic studies have implicated PCDH10, a member of the δ2 subfamily of nonclustered protocadherin genes, in ASD. PCDH10 expression is enriched in the basolateral amygdala, a brain region implicated in the social deficits of ASD. Previous reports indicate that Pcdh10 plays a role in axon outgrowth and glutamatergic synapse elimination, but its roles in social behaviors and amygdala neuronal connectivity are unknown. We hypothesized that haploinsufficiency of Pcdh10 would reduce social approach behavior and alter the structure and function of amygdala circuits. Mice lacking one copy of Pcdh10 (Pcdh10 +/- ) and wild-type littermates were assessed for social approach and other behaviors. The lateral/basolateral amygdala was assessed for dendritic spine number and morphology, and amygdala circuit function was studied using voltage-sensitive dye imaging. Expression of Pcdh10 and N-methyl-D-aspartate receptor (NMDAR) subunits was assessed in postsynaptic density fractions of the amygdala. Male Pcdh10 +/- mice have reduced social approach behavior, as well as impaired gamma synchronization, abnormal spine morphology, and reduced levels of NMDAR subunits in the amygdala. Social approach deficits in Pcdh10 +/- male mice were rescued with acute treatment with the NMDAR partial agonist d-cycloserine. Our studies reveal that male Pcdh10 +/- mice have synaptic and behavioral deficits, and establish Pcdh10 +/- mice as a novel genetic model for investigating neural circuitry and behavioral changes relevant to ASD. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  4. Comparative study of the protein profiles of Sunki mandarin and Rangpur lime plants in response to water deficit.

    Science.gov (United States)

    Oliveira, Tahise M; da Silva, Fernanda R; Bonatto, Diego; Neves, Diana M; Morillon, Raphael; Maserti, Bianca E; Filho, Mauricio A Coelho; Costa, Marcio G C; Pirovani, Carlos P; Gesteira, Abelmon S

    2015-03-03

    Rootstocks play a major role in the tolerance of citrus plants to water deficit by controlling and adjusting the water supply to meet the transpiration demand of the shoots. Alterations in protein abundance in citrus roots are crucial for plant adaptation to water deficit. We performed two-dimensional electrophoresis (2-DE) separation followed by LC/MS/MS to assess the proteome responses of the roots of two citrus rootstocks, Rangpur lime (Citrus limonia Osbeck) and 'Sunki Maravilha' (Citrus sunki) mandarin, which show contrasting tolerances to water deficits at the physiological and molecular levels. Changes in the abundance of 36 and 38 proteins in Rangpur lime and 'Sunki Maravilha' mandarin, respectively, were observed via LC/MS/MS in response to water deficit. Multivariate principal component analysis (PCA) of the data revealed major changes in the protein profile of 'Sunki Maravilha' in response to water deficit. Additionally, proteomics and systems biology analyses allowed for the general elucidation of the major mechanisms associated with the differential responses to water deficit of both varieties. The defense mechanisms of Rangpur lime included changes in the metabolism of carbohydrates and amino acids as well as in the activation of reactive oxygen species (ROS) detoxification and in the levels of proteins involved in water stress defense. In contrast, the adaptation of 'Sunki Maravilha' to stress was aided by the activation of DNA repair and processing proteins. Our study reveals that the levels of a number of proteins involved in various cellular pathways are affected during water deficit in the roots of citrus plants. The results show that acclimatization to water deficit involves specific responses in Rangpur lime and 'Sunki Maravilha' mandarin. This study provides insights into the effects of drought on the abundance of proteins in the roots of two varieties of citrus rootstocks. In addition, this work allows for a better understanding of the

  5. Alterations of Growth Factors in Autism and Attention-Deficit/Hyperactivity Disorder

    Directory of Open Access Journals (Sweden)

    Alma Y. Galvez-Contreras

    2017-07-01

    Full Text Available Growth factors (GFs are cytokines that regulate the neural development. Recent evidence indicates that alterations in the expression level of GFs during embryogenesis are linked to the pathophysiology and clinical manifestations of attention-deficit/hyperactivity disorder (ADHD and autism spectrum disorders (ASD. In this concise review, we summarize the current evidence that supports the role of brain-derived neurotrophic factor, insulin-like growth factor 2, hepatocyte growth factor (HGF, glial-derived neurotrophic factor, nerve growth factor, neurotrophins 3 and 4, and epidermal growth factor in the pathogenesis of ADHD and ASD. We also highlight the potential use of these GFs as clinical markers for diagnosis and prognosis of these neurodevelopmental disorders.

  6. Alterations of Growth Factors in Autism and Attention-Deficit/Hyperactivity Disorder

    Science.gov (United States)

    Galvez-Contreras, Alma Y.; Campos-Ordonez, Tania; Gonzalez-Castaneda, Rocio E.; Gonzalez-Perez, Oscar

    2017-01-01

    Growth factors (GFs) are cytokines that regulate the neural development. Recent evidence indicates that alterations in the expression level of GFs during embryogenesis are linked to the pathophysiology and clinical manifestations of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASD). In this concise review, we summarize the current evidence that supports the role of brain-derived neurotrophic factor, insulin-like growth factor 2, hepatocyte growth factor (HGF), glial-derived neurotrophic factor, nerve growth factor, neurotrophins 3 and 4, and epidermal growth factor in the pathogenesis of ADHD and ASD. We also highlight the potential use of these GFs as clinical markers for diagnosis and prognosis of these neurodevelopmental disorders. PMID:28751869

  7. Extreme Water Deficit in Brazil Detected from Space

    Science.gov (United States)

    Vieira Getirana

    2016-01-01

    Extreme droughts have caused significant socioeconomic and environmental damage worldwide. In Brazil, ineffective energy development and water management policies have magnified the impacts of recent severe droughts, which include massive agricultural losses, water supply restrictions, and energy rationing. Spaceborne remote sensing data advance our understanding of the spatiotemporal variability of large-scale droughts and enhance the detection and monitoring of extreme water-related events. In this study, data derived from the Gravity Recovery and Climate Experiment (GRACE) mission are used to detect and quantify an extended major drought over eastern Brazil and provide estimates of impacted areas and region-specific water deficits. Two structural breakpoint detection methods were applied to time series of GRACE-based terrestrial water storage anomalies (TWSA), determining when two abrupt changes occurred. One, in particular, defines the beginning of the current drought. Using TWSA, a water loss rate of 26.1 cmyr21 over southeastern Brazil was detected from 2012 to 2015. Based on analysis of Global Land Data Assimilation System(GLDAS) outputs, the extreme drought is mostly related to lower-than-usual precipitation rates, resulting in high soil moisture depletion and lower-than-usual rates of evapotranspiration. A reduction of 2023 of precipitation over an extended period of 3 years is enough to raise serious water scarcity conditions in the country. Correlations between monthly time series of both grid-based TWSA and ground-based water storage measurements at 16 reservoirs located within southeastern Brazil varied from 0.42 to 0.82. Differences are mainly explained by reservoir sizes and proximity to the drought nucleus.

  8. Extensive tissue-specific transcriptomic plasticity in maize primary roots upon water deficit

    OpenAIRE

    Opitz, Nina; Marcon, Caroline; Paschold, Anja; Malik, Waqas Ahmed; Lithio, Andrew; Brandt, Ronny; Piepho, Hans-Peter; Nettleton, Dan; Hochholdinger, Frank

    2015-01-01

    Water deficit is the most important environmental constraint severely limiting global crop growth and productivity. This study investigated early transcriptome changes in maize (Zea mays L.) primary root tissues in response to moderate water deficit conditions by RNA-Sequencing. Differential gene expression analyses revealed a high degree of plasticity of the water deficit response. The activity status of genes (active/inactive) was determined by a Bayesian hierarchical model. In total, 70% o...

  9. Altered regional homogeneity patterns in adults with attention-deficit hyperactivity disorder

    International Nuclear Information System (INIS)

    Wang, Xunheng; Jiao, Yun; Tang, Tianyu; Wang, Hui; Lu, Zuhong

    2013-01-01

    Purpose: Investigating the discriminative brain map for patients with attention-deficit/hyperactivity disorder (ADHD) based on feature selection and classifier; and identifying patients with ADHD based on the discriminative model. Materials and methods: A dataset of resting state fMRI contains 23 patients with ADHD and 23 healthy subjects were analyzed. Regional homogeneity (ReHo) was extracted from resting state fMRI signals and used as model inputs. Raw ReHo features were ranked and selected in a loop according to their p values. Selected features were trained and tested by support vector machines (SVM) in a cross validation procedure. Cross validation was repeated in feature selection loop to produce optimized model. Results: Optimized discriminative map indicated that the ADHD brains exhibit more increased activities than normal controls in bilateral occipital lobes and left front lobe. The altered brain regions included portions of basal ganglia, insula, precuneus, anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), thalamus, and cerebellum. Correlation coefficients indicated significant positive correlation of inattentive scores with bilateral cuneus and precuneus, and significant negative correlation of hyperactive/impulsive scores with bilateral insula and claustrum. Additionally, the optimized model produced total accuracy of 80% and sensitivity of 87%. Conclusion: ADHD brain regions were more activated than normal controls during resting state. Linear support vector classifier can provide useful discriminative information of altered ReHo patterns for ADHD; and feature selection can improve the performances of classification

  10. Altered regional homogeneity patterns in adults with attention-deficit hyperactivity disorder

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xunheng [School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096 (China); Key Laboratory of Child Development and Learning Science (Ministry of Education), Southeast University, Nanjing 210096 (China); Jiao, Yun, E-mail: yunjiao@seu.edu.cn [Jiangsu Key Laboratory of Molecular Imaging and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School of Southeast University, Nanjing 210009 (China); Tang, Tianyu; Wang, Hui; Lu, Zuhong [School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096 (China); Key Laboratory of Child Development and Learning Science (Ministry of Education), Southeast University, Nanjing 210096 (China)

    2013-09-15

    Purpose: Investigating the discriminative brain map for patients with attention-deficit/hyperactivity disorder (ADHD) based on feature selection and classifier; and identifying patients with ADHD based on the discriminative model. Materials and methods: A dataset of resting state fMRI contains 23 patients with ADHD and 23 healthy subjects were analyzed. Regional homogeneity (ReHo) was extracted from resting state fMRI signals and used as model inputs. Raw ReHo features were ranked and selected in a loop according to their p values. Selected features were trained and tested by support vector machines (SVM) in a cross validation procedure. Cross validation was repeated in feature selection loop to produce optimized model. Results: Optimized discriminative map indicated that the ADHD brains exhibit more increased activities than normal controls in bilateral occipital lobes and left front lobe. The altered brain regions included portions of basal ganglia, insula, precuneus, anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), thalamus, and cerebellum. Correlation coefficients indicated significant positive correlation of inattentive scores with bilateral cuneus and precuneus, and significant negative correlation of hyperactive/impulsive scores with bilateral insula and claustrum. Additionally, the optimized model produced total accuracy of 80% and sensitivity of 87%. Conclusion: ADHD brain regions were more activated than normal controls during resting state. Linear support vector classifier can provide useful discriminative information of altered ReHo patterns for ADHD; and feature selection can improve the performances of classification.

  11. Berry composition and yield of Cabernet Sauvignon and Malbec in response to water deficit severity

    Science.gov (United States)

    Water supply is a production tool used in arid climates to elicit desirable, water-deficit related changes in berry composition and yield; however, response to water deficit is known to vary by cultivar. The objectives of this research were to determine whether cultivars differed in their relations...

  12. Water-deficit tolerant classification in mutant lines of indica rice

    Directory of Open Access Journals (Sweden)

    Suriyan Cha-um

    2012-04-01

    Full Text Available Water shortage is a major abiotic stress for crop production worldwide, limiting the productivity of crop species, especially in dry-land agricultural areas. This investigation aimed to classify the water-deficit tolerance in mutant rice (Oryza sativa L. spp. indica genotypes during the reproductive stage. Proline content in the flag leaf of mutant lines increased when plants were subjected to water deficit. Relative water content (RWC in the flag leaf of different mutant lines dropped in relation to water deficit stress. A decrease RWC was positively related to chlorophyll a degradation. Chlorophyll a , chlorophyll b , total chlorophyll , total carotenoids , maximum quantum yield of PSII , stomatal conductance , transpiration rate and water use efficiency in mutant lines grown under water deficit conditions declined in comparison to the well-watered, leading to a reduction in net-photosynthetic rate. In addition, when exposed to water deficit, panicle traits, including panicle length and fertile grains were dropped. The biochemical and physiological data were subjected to classify the water deficit tolerance. NSG19 (positive control and DD14 were identified as water deficit tolerant, and AA11, AA12, AA16, BB13, BB16, CC12, CC15, EE12, FF15, FF17, G11 and IR20 (negative control as water deficit sensitive, using Ward's method.

  13. Effects of phosphorus application on photosynthetic carbon and nitrogen metabolism, water use efficiency and growth of dwarf bamboo (Fargesia rufa) subjected to water deficit.

    Science.gov (United States)

    Liu, Chenggang; Wang, Yanjie; Pan, Kaiwen; Jin, Yanqiang; Li, Wei; Zhang, Lin

    2015-11-01

    Dwarf bamboo (Fargesia rufa Yi), one of the staple foods for the endangered giant pandas, is highly susceptible to water deficit due to its shallow roots. In the face of climate change, maintenance and improvement in its productivity is very necessary for the management of the giant pandas' habitats. However, the regulatory mechanisms underlying plant responses to water deficit are poorly known. To investigate the effects of P application on photosynthetic C and N metabolism, water use efficiency (WUE) and growth of dwarf bamboo under water deficit, a completely randomized design with two factors of two watering (well-watered and water-stressed) and two P regimes (with and without P fertilization) was arranged. P application hardly changed growth, net CO2 assimilation rate (P(n)) and WUE in well-watered plants but significantly increased relative growth rate (RGR) and P(n) in water-stressed plants. The effect of P application on RGR under water stress was mostly associated with physiological adjustments rather than with differences in biomass allocation. P application maintained the balance of C metabolism in well-watered plants, but altered the proportion of nitrogenous compounds in N metabolism. By contrast, P application remarkably increased sucrose-metabolizing enzymes activities with an obvious decrease in sucrose content in water-stressed plants, suggesting an accelerated sucrose metabolism. Activation of nitrogen-metabolizing enzymes in water-stressed plants was attenuated after P application, thus slowing nitrate reduction and ammonium assimilation. P application hardly enlarged the phenotypic plasticity of dwarf bamboo in response to water in the short term. Generally, these examined traits of dwarf bamboo displayed weak or negligible responses to water-P interaction. In conclusion, P application could accelerate P(n) and sucrose metabolism and slow N metabolism in water-stressed dwarf bamboo, and as a result improved RGR and alleviated damage from soil

  14. Altered Kinematics of Facial Emotion Expression and Emotion Recognition Deficits Are Unrelated in Parkinson?s Disease

    OpenAIRE

    Bologna, Matteo; Berardelli, Isabella; Paparella, Giulia; Marsili, Luca; Ricciardi, Lucia; Fabbrini, Giovanni; Berardelli, Alfredo

    2016-01-01

    Background Altered emotional processing, including reduced emotion facial expression and defective emotion recognition, has been reported in patients with Parkinson?s disease (PD). However, few studies have objectively investigated facial expression abnormalities in PD using neurophysiological techniques. It is not known whether altered facial expression and recognition in PD are related. Objective To investigate possible deficits in facial emotion expression and emotion recognition and their...

  15. Chlorophyll fluorescence response to water and nitrogen deficit

    Science.gov (United States)

    Cendrero Mateo, Maria del Pilar

    The increasing food demand as well as the need to predict the impact of warming climate on vegetation makes it critical to find the best tools to assess crop production and carbon dioxide (CO2) exchange between the land and atmosphere. Photosynthesis is a good indicator of crop production and CO2 exchange. Chlorophyll fluorescence (ChF) is directly related to photosynthesis. ChF can be measured at leaf-scale using active techniques and at field-scales using passive techniques. The measurement principles of both techniques are different. In this study, three overarching questions about ChF were addressed: Q1) How water, nutrient and ambient light conditions determine the relationships between photosynthesis and ChF? Which is the optimum irradiance level for detecting water and nutrient deficit conditions with ChF? ; Q2) which are the limits within which active and passive techniques are comparable?; and Q3) What is the seasonal relationship between photosynthesis and ChF when nitrogen is the limiting factor? To address these questions, two main experiments were conducted: Exp1) Concurrent photosynthesis and ChF light-response curves were measured in camelina and wheat plants growing under (i) intermediate-light and (ii) high-light conditions respectively. Plant stress was induced by (i) withdrawing water, and (ii) applying different nitrogen levels; and Exp2) coincident active and passive ChF measurements were made in a wheat field under different nitrogen treatments. The results indicated ChF has a direct relationship with photosynthesis when water or nitrogen drives the relationship. This study demonstrates that the light level at which plants were grown was optimum for detecting water and nutrient deficit with ChF. Also, the results showed that for leaf-average-values, active measurements can be used to better understand the daily and seasonal behavior of passive ChF. Further, the seasonal relation between photosynthesis and ChF with nitrogen stress was not a

  16. Altered resting-state frontoparietal control network in children with attention-deficit/hyperactivity disorder.

    Science.gov (United States)

    Lin, Hsiang-Yuan; Tseng, Wen-Yih Isaac; Lai, Meng-Chuan; Matsuo, Kayako; Gau, Susan Shur-Fen

    2015-04-01

    The frontoparietal control network, anatomically and functionally interposed between the dorsal attention network and default mode network, underpins executive control functions. Individuals with attention-deficit/hyperactivity disorder (ADHD) commonly exhibit deficits in executive functions, which are mainly mediated by the frontoparietal control network. Involvement of the frontoparietal control network based on the anterior prefrontal cortex in neurobiological mechanisms of ADHD has yet to be tested. We used resting-state functional MRI and seed-based correlation analyses to investigate functional connectivity of the frontoparietal control network in a sample of 25 children with ADHD (7-14 years; mean 9.94 ± 1.77 years; 20 males), and 25 age-, sex-, and performance IQ-matched typically developing (TD) children. All participants had limited in-scanner head motion. Spearman's rank correlations were used to test the associations between altered patterns of functional connectivity with clinical symptoms and executive functions, measured by the Conners' Continuous Performance Test and Spatial Span in the Cambridge Neuropsychological Test Automated Battery. Compared with TD children, children with ADHD demonstrated weaker connectivity between the right anterior prefrontal cortex (PFC) and the right ventrolateral PFC, and between the left anterior PFC and the right inferior parietal lobule. Furthermore, this aberrant connectivity of the frontoparietal control network in ADHD was associated with symptoms of impulsivity and opposition-defiance, as well as impaired response inhibition and attentional control. The findings support potential integration of the disconnection model and the executive dysfunction model for ADHD. Atypical frontoparietal control network may play a pivotal role in the pathophysiology of ADHD.

  17. Survey the Effects of Partial Root Zone Deficit Irrigation and Deficit Irrigation on Quantitative, Qualitative and Water Use Efficiency of Pomegranate

    OpenAIRE

    mohammad saeed tadaion; Gholamreza Moafpourian

    2017-01-01

    Introduction: One of the latest efficient methods on increment of water use efficiency that confirmed by many scientists all over the world is deficit and alternative partial root zone deficit irrigation. In this experiment the effect of deficit and alternative partial root zone deficit irrigation on fruit yield, quality and water use efficiency of pomegranate (Punicagranatum (L.) cv. Zarde-anar) were investigatedin Arsenjan semi-arid region. Materials and Methods: The experiment was carri...

  18. Distribution and utilization of 15N in cowpeas injected into the stem under influence of water deficit.

    Science.gov (United States)

    Götz K-P; Herzog, H

    2000-01-01

    Investigations were carried out on Vigna unguiculata L. Walp. to estimate the distribution and utilization of 15N in different organs after stem injection during vegetative, flowering and pod filling stage. During flowering effects of water deficit were also examined. In well watered plants, within 4 days after injection, 65% of 15N accumulated in leaves. This was drastically reduced to 42% by water deficit. 15N accumulation in stems increased under water deficit. The translocation of 15N from the stem base to roots were not altered by water deficit. During pod filling 62% of recovered 15N in the plants had accumulated in seeds, 24% in leaves and 11% in stems within 4 days, whereas the uptake of nitrogen in pod walls and roots remained low (2%). These results demonstrate that the method of injecting very small quantities (1 mg/plant) of 15N into the stem base allows an exact and detailed quantitative assessment of N translocation/distribution with regard to different organs, different growth stages and different treatments.

  19. [Effects of water deficit and nitrogen fertilization on winter wheat growth and nitrogen uptake].

    Science.gov (United States)

    Qi, You-Ling; Zhang, Fu-Cang; Li, Kai-Feng

    2009-10-01

    Winter wheat plants were cultured in vitro tubes to study their growth and nitrogen uptake under effects of water deficit at different growth stages and nitrogen fertilization. Water deficit at any growth stages could obviously affect the plant height, leaf area, dry matter accumulation, and nitrogen uptake. Jointing stage was the most sensitive stage of winter wheat growth to water deficit, followed by flowering stage, grain-filling stage, and seedling stages. Rewatering after the water deficit at seedling stage had a significant compensation effect on winter wheat growth, and definite compensation effect was observed on the biomass accumulation and nitrogen absorption when rewatering was made after the water deficit at flowering stage. Under the same nitrogen fertilization levels, the nitrogen accumulation in root with water deficit at seedling, jointing, flowering, and grain-filling stages was reduced by 25.82%, 55.68%, 46.14%, and 16.34%, and the nitrogen accumulation in aboveground part was reduced by 33.37%, 51.71%, 27.01%, and 2.60%, respectively, compared with no water deficit. Under the same water deficit stages, the nitrogen content and accumulation of winter wheat decreased with decreasing nitrogen fertilization level, i. e., 0.3 g N x kg(-1) FM > 0.2 g N x kg(-1) FM > 0.1 g N x kg(-1) FM. Nitrogen fertilization had obvious regulation effect on winter wheat plant growth, dry matter accumulation, and nitrogen uptake under water stress.

  20. Analysis of the Citrullus colocynthis transcriptome during water deficit stress.

    Directory of Open Access Journals (Sweden)

    Zhuoyu Wang

    Full Text Available Citrullus colocynthis is a very drought tolerant species, closely related to watermelon (C. lanatus var. lanatus, an economically important cucurbit crop. Drought is a threat to plant growth and development, and the discovery of drought inducible genes with various functions is of great importance. We used high throughput mRNA Illumina sequencing technology and bioinformatic strategies to analyze the C. colocynthis leaf transcriptome under drought treatment. Leaf samples at four different time points (0, 24, 36, or 48 hours of withholding water were used for RNA extraction and Illumina sequencing. qRT-PCR of several drought responsive genes was performed to confirm the accuracy of RNA sequencing. Leaf transcriptome analysis provided the first glimpse of the drought responsive transcriptome of this unique cucurbit species. A total of 5038 full-length cDNAs were detected, with 2545 genes showing significant changes during drought stress. Principle component analysis indicated that drought was the major contributing factor regulating transcriptome changes. Up regulation of many transcription factors, stress signaling factors, detoxification genes, and genes involved in phytohormone signaling and citrulline metabolism occurred under the water deficit conditions. The C. colocynthis transcriptome data highlight the activation of a large set of drought related genes in this species, thus providing a valuable resource for future functional analysis of candidate genes in defense of drought stress.

  1. Long-term Root Growth Response to Thinning, Fertilization, and Water Deficit in Plantation Loblolly Pine

    Science.gov (United States)

    M.A. Sword-Sayer; Z. Tang

    2004-01-01

    High water deficits limit the new root growth of loblolly pine (Pinus taeda L.), potentially reducing soil resource availability and stand growth. We evaluated new root growth and stand production in response to thinning and fertilization in loblolly pine over a 6-year period that consisted of 3 years of low water deficit followed by 3 years of high...

  2. Genetic control of plasticity in root morphology and anatomy of rice in response to water deficit

    NARCIS (Netherlands)

    Kadam, Niteen N.; Tamilselvan, Anandhan; Lawas, Lovely M.F.; Quinones, Cherryl; Bahuguna, Rajeev N.; Thomson, Michael J.; Dingkuhn, Michael; Muthurajan, Raveendran; Struik, Paul C.; Yin, Xinyou; Jagadish, Krishna S.V.

    2017-01-01

    Elucidating the genetic control of rooting behavior under water-deficit stress is essential to breed climate-robust rice (Oryza sativa) cultivars. Using a diverse panel of 274 indica genotypes grown under control and water-deficit conditions during vegetative growth, we phenotyped 35 traits, mostly

  3. Extensive tissue-specific transcriptomic plasticity in maize primary roots upon water deficit.

    Science.gov (United States)

    Opitz, Nina; Marcon, Caroline; Paschold, Anja; Malik, Waqas Ahmed; Lithio, Andrew; Brandt, Ronny; Piepho, Hans-Peter; Nettleton, Dan; Hochholdinger, Frank

    2016-02-01

    Water deficit is the most important environmental constraint severely limiting global crop growth and productivity. This study investigated early transcriptome changes in maize (Zea mays L.) primary root tissues in response to moderate water deficit conditions by RNA-Sequencing. Differential gene expression analyses revealed a high degree of plasticity of the water deficit response. The activity status of genes (active/inactive) was determined by a Bayesian hierarchical model. In total, 70% of expressed genes were constitutively active in all tissues. In contrast, deficit-responsive genes (1915) were consistently regulated in all tissues, while >75% (1501 genes) were specifically regulated in a single root tissue. Water deficit-responsive genes were most numerous in the cortex of the mature root zone and in the elongation zone. The most prominent functional categories among differentially expressed genes in all tissues were 'transcriptional regulation' and 'hormone metabolism', indicating global reprogramming of cellular metabolism as an adaptation to water deficit. Additionally, the most significant transcriptomic changes in the root tip were associated with cell wall reorganization, leading to continued root growth despite water deficit conditions. This study provides insight into tissue-specific water deficit responses and will be a resource for future genetic analyses and breeding strategies to develop more drought-tolerant maize cultivars. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  4. Responses of seminal wheat seedling roots to soil water deficits.

    Science.gov (United States)

    Trejo, Carlos; Else, Mark A; Atkinson, Christopher J

    2018-04-01

    The aims of this paper are to develop our understanding of the ways by which soil water deficits influence early wheat root growth responses, particularly how seminal roots respond to soil drying and the extent to which information on differences in soil water content are conveyed to the shoot and their impact on shoot behaviour. To achieve this, wheat seedlings have been grown, individually for around 25 days after germination in segmented soil columns within vertical plastic compartments. Roots were exposed to different soil volumetric moisture contents (SVMC) within the two compartments. Experiments where the soil in the lower compartment was allowed to dry to different extents, while the upper was maintained close to field capacity, showed that wheat seedlings allocated proportionally more root dry matter to the lower drier soil compartment. The total production of root, irrespective of the upper or lower SVMC, was similar and there were no detected effects on leaf growth rate or gas exchange. The response of seminal roots to proportionally increase their allocation of dry matter, to the drier soil was unexpected with such plasticity of roots system development traditionally linked to heterogeneous nutrient distribution than accessing soil water. In experiments where the upper soil compartment was allowed to dry, root growth slowed and leaf growth and gas exchange declined. Subsequent experiments used root growth rates to determine when seminal root tips first came into contact with drying soil, with the intentions of determining how the observed root growth rates were maintained as an explanation for the observed changes in root allocation. Measurements of seminal root ABA and ethylene from roots within the drying soil are interpreted with respect to what is known about the physiological control of root growth in drying soil. Copyright © 2018 Elsevier GmbH. All rights reserved.

  5. Altered cortical thickness and attentional deficits in adolescent girls and women with bulimia nervosa.

    Science.gov (United States)

    Berner, Laura A; Stefan, Mihaela; Lee, Seonjoo; Wang, Zhishun; Terranova, Kate; Attia, Evelyn; Marsh, Rachel

    2018-01-12

    Frontostriatal and frontoparietal abnormalities likely contribute to deficits in control and attentional processes in individuals with bulimia nervosa and to the persistence of dysregulated eating across development. This study assessed these processes and cortical thickness in a large sample of adolescent girls and women with bulimia nervosa compared with healthy controls. We collected anatomical MRI data from adolescent girls and women (ages 12-38 yr) with full or subthreshold bulimia nervosa and age-matched healthy controls who also completed the Conners Continuous Performance Test-II (CPT-II). Groups were compared on task performance and cortical thickness. Mediation analyses explored associations among cortical thickness, CPT-II variables, bulimia nervosa symptoms and age. We included 60 girls and women with bulimia nervosa and 54 controls in the analyses. Compared with healthy participants, those with bulimia nervosa showed increased impulsivity and inattention on the CPT-II, along with reduced thickness of the right pars triangularis, right superior parietal and left dorsal posterior cingulate cortices. In the bulimia nervosa group, exploratory analyses revealed that binge eating frequency correlated inversely with cortical thickness of frontoparietal and insular regions and that reduced frontoparietal thickness mediated the association between age and increased symptom severity and inattention. Binge eating frequency also mediated the association between age and lower prefrontal cortical thickness. These findings are applicable to only girls and women with bulimia nervosa, and our cross-sectional design precludes understanding of whether cortical thickness alterations precede or result from bulimia nervosa symptoms. Structural abnormalities in the frontoparietal and posterior cingulate regions comprising circuits that support control and attentional processes should be investigated as potential contributors to the maintenance of bulimia nervosa and useful

  6. Altered cortical thickness and attentional deficits in adolescent girls and women with bulimia nervosa.

    Science.gov (United States)

    Berner, Laura A; Stefan, Mihaela; Lee, Seonjoo; Wang, Zhishun; Terranova, Kate; Attia, Evelyn; Marsh, Rachel

    2018-05-01

    Frontostriatal and frontoparietal abnormalities likely contribute to deficits in control and attentional processes in individuals with bulimia nervosa and to the persistence of dysregulated eating across development. This study assessed these processes and cortical thickness in a large sample of adolescent girls and women with bulimia nervosa compared with healthy controls. We collected anatomical MRI data from adolescent girls and women (ages 12-38 yr) with full or subthreshold bulimia nervosa and age-matched healthy controls who also completed the Conners Continuous Performance Test-II (CPT-II). Groups were compared on task performance and cortical thickness. Mediation analyses explored associations among cortical thickness, CPT-II variables, bulimia nervosa symptoms and age. We included 60 girls and women with bulimia nervosa and 54 controls in the analyses. Compared with healthy participants, those with bulimia nervosa showed increased impulsivity and inattention on the CPT-II, along with reduced thickness of the right pars triangularis, right superior parietal and left dorsal posterior cingulate cortices. In the bulimia nervosa group, exploratory analyses revealed that binge eating frequency correlated inversely with cortical thickness of frontoparietal and insular regions and that reduced frontoparietal thickness mediated the association between age and increased symptom severity and inattention. Binge eating frequency also mediated the association between age and lower prefrontal cortical thickness. These findings are applicable to only girls and women with bulimia nervosa, and our cross-sectional design precludes understanding of whether cortical thickness alterations precede or result from bulimia nervosa symptoms. Structural abnormalities in the frontoparietal and posterior cingulate regions comprising circuits that support control and attentional processes should be investigated as potential contributors to the maintenance of bulimia nervosa and useful

  7. Altered cortical thickness and attentional deficits in adolescent girls and women with bulimia nervosa

    Science.gov (United States)

    Stefan, Mihaela; Lee, Seonjoo; Wang, Zhishun; Terranova, Kate; Attia, Evelyn; Marsh, Rachel

    2018-01-01

    Background Frontostriatal and frontoparietal abnormalities likely contribute to deficits in control and attentional processes in individuals with bulimia nervosa and to the persistence of dysregulated eating across development. This study assessed these processes and cortical thickness in a large sample of adolescent girls and women with bulimia nervosa compared with healthy controls. Methods We collected anatomical MRI data from adolescent girls and women (ages 12–38 yr) with full or subthreshold bulimia nervosa and age-matched healthy controls who also completed the Conners Continuous Performance Test-II (CPT-II). Groups were compared on task performance and cortical thickness. Mediation analyses explored associations among cortical thickness, CPT-II variables, bulimia nervosa symptoms and age. Results We included 60 girls and women with bulimia nervosa and 54 controls in the analyses. Compared with healthy participants, those with bulimia nervosa showed increased impulsivity and inattention on the CPT-II, along with reduced thickness of the right pars triangularis, right superior parietal and left dorsal posterior cingulate cortices. In the bulimia nervosa group, exploratory analyses revealed that binge eating frequency correlated inversely with cortical thickness of frontoparietal and insular regions and that reduced frontoparietal thickness mediated the association between age and increased symptom severity and inattention. Binge eating frequency also mediated the association between age and lower prefrontal cortical thickness. Limitations These findings are applicable to only girls and women with bulimia nervosa, and our cross-sectional design precludes understanding of whether cortical thickness alterations precede or result from bulimia nervosa symptoms. Conclusion Structural abnormalities in the frontoparietal and posterior cingulate regions comprising circuits that support control and attentional processes should be investigated as potential

  8. Impacts of deficit irrigation and altered rooting patterns on soil structure and associated soil properties

    Science.gov (United States)

    A better understanding of belowground systems and overall management impacts on soil health is needed to improve crop production and long-term sustainability under deficit irrigation. This study investigates effects of deficit irrigation on rooting patterns in maize and subsequent impacts on soil pr...

  9. Tomato Yield and Water Use Efficiency - Coupling Effects between Growth Stage Specific Soil Water Deficits

    DEFF Research Database (Denmark)

    Chen, Si; Zhenjiang, Zhou; Andersen, Mathias Neumann

    2015-01-01

    To investigate the sensitivity of tomato yield and water use efficiency (WUE) to soil water content at different growth stages, the central composite rotatable design (CCRD) was employed in a five-factor-five-level pot experiment under regulated deficit irrigation. Two regression models concerning...... the effects of stage-specific soil water content on tomato yield and WUE were established. The results showed that the lowest available soil water (ASW) content (around 28%) during vegetative growth stage (here denoted θ1) resulted in high yield and WUE. Moderate (around 69% ASW) during blooming and fruit...... effects of ASW in two growth stages were between θ2 and θ5, θ3. In both cases a moderate θ2 was a precondition for maximum yield response to increasing θ5 and θ3. Sensitivity analysis revealed that yield was most sensitive to soil water content at fruit maturity (θ5). Numerical inspection...

  10. Effects of Nutrients Foliar Application on Agrophysiological Characteristics of Maize under Water Deficit Stress

    Directory of Open Access Journals (Sweden)

    Nour Ali SAJEDI

    2010-09-01

    Full Text Available To investigate effects of nutrients foliar application on agrophysiological characteristics of maize hybrid �KSC 704� water deficit stress conditions, an experiment was arranged in a split plot factorial based on a randomized complete block design with four replications to the Research Station of Islamic Azad University-Arak Branch, Iran in 2007-2008. Main factors studied were four irrigation levels including irrigation equal to crop water requirement, water deficit stress at eight-leaf stage (V8, blister stage (R2 and filling grain stage (R4 in the main plot. Combined levels of selenium treatment (without and with application 20 gha-1 and micronutrients (without and with application 2 lha-1 were situated in sub plots. Results showed that water deficit stress decreased grain yield 19.7% in blister stage as compared with control. Using selenium increased relative content water at R2 and R4 stages significantly. Using selenium in water deficit stress condition increased measured traits except plant height as compared with treatment without selenium. A negative antagonistic interaction was found between selenium and micronutrients on some measured traits. Between treatments of water deficit stress, highest grain yield equal 6799.52 and 6736.97 kgha-1 was obtained from combined treatments of water deficit stress at eight-leaf stage+without selenium+without micronutrients and water deficit stress at eight-leaf stage+selenium+without micronutrients respectively which compared with treatment of irrigation equal to crop water requirement+selenium+microelements did not differ significant. According to the results of experiment, it is concluded that with micronutrients fertilizer spray under optimum irrigation and selenium spray under water deficit obtain optimum yield.

  11. Nitrogen accumulation in lucerne (Medicago sativa L. under water deficit stress

    Directory of Open Access Journals (Sweden)

    Vasileva Viliana

    2013-01-01

    Full Text Available In order to study nitrogen accumulation in aboveground and root dry mass in lucerne (Medicago sativa L. under water deficit stress, a pot experiment was carried out at the Institute of Forage Crops, Pleven, Bulgaria. The plants were grown under optimum water supply (75-80% FC and 10-days water deficit stress was simulated at the stage of budding by interrupting the irrigation until soil moisture was reduced to 37-40% FC. Mineral nitrogen fertilization (ammonium nitrate at the doses of 40, 80, 120 and 160 mg N kg-1 soil was applied. It was found that nitrogen accumulation in dry aboveground mass was reduced to 18.0%, and in dry root mass to 26.5% under water deficit stress. Mineral nitrogen fertilization contributed to easily overcome the stress conditions of water deficit stress in lucerne.

  12. Physiological and biochemical changes in Matricaria chamomilla induced by Pseudomonas fluorescens and water deficit stress

    Directory of Open Access Journals (Sweden)

    Hamid MOHAMMADI

    2018-04-01

    Full Text Available Environmental stresses and rhizosphere microorganisms affect growth parameters and accumulation of active ingredients especially in plants with medicinal properties. The present study examined the effects of chamomile (Matricaria chamomilla L. seedling inoculation with Pseudomonas fluorescens PF-135 strain on its growth parameters, photosynthetic pigments, proline, malondialdehyde (MDA, and hydrogen peroxide (H2O2 content, and essential oil concentration at both regular watering and water deficit experiments. Based on the obtained results, water deficit stress reduced root dry mass, and flower fresh and dry mass as well. However, amount of H2O2 and MDA in root and shoot tissues were considerably lower in inoculated plants compared to non-inoculated ones under both normal watering and water deficit regimes. It indicates that lipid peroxidation and production of reactive oxygen species has been diminished in inoculated plants. Also, essential oil content in inoculated plants significantly increased compared with that of non-inoculated ones under water deficit stress condition. It can be concluded that P. fluorescens PF-135 strain has an outstanding potential to alleviate adverse effects of water deficit on plant growth, and hence can be used as an excellent PGPR in order to boost chamomile productivity especially under water deficit stress condition.

  13. Transpiration and leaf growth of potato clones in response to soil water deficit

    Directory of Open Access Journals (Sweden)

    André Trevisan de Souza

    2014-04-01

    Full Text Available Potato (Solanum tuberosum ssp. Tuberosum crop is particularly susceptible to water deficit because of its small and shallow root system. The fraction of transpirable soil water (FTSW approach has been widely used in the evaluation of plant responses to water deficit in different crops. The FTSW 34 threshold (when stomatal closure starts is a trait of particular interest because it is an indicator of tolerance to water deficit. The FTSW threshold for decline in transpiration and leaf growth was evaluated in a drying soil to identify potato clones tolerant to water deficit. Two greenhouse experiments were carried out in pots, with three advanced clones and the cultivar Asterix. The FTSW, transpiration and leaf growth were measured on a daily basis, during the period of soil drying. FTSW was an efficient method to separate potato clones with regard to their response to water deficit. The advancedclones SMINIA 02106-11 and SMINIA 00017-6 are more tolerant to soil water deficit than the cultivar Asterix, and the clone SMINIA 793101-3 is more tolerant only under high solar radiation.

  14. Source-sink relationships in two soybean cultivars with indeterminate growth under water deficit

    Directory of Open Access Journals (Sweden)

    Alexandre José da Silva

    Full Text Available Abstract Water deficit is a major factor limiting crop yield in rainfed areas. We hypothesized that under water deficit the decrease of photosynthetic production stimulates: carbohydrate remobilization from leaves, stems and roots to reproductive organs; and decreasing flowering intensity and pod development. The present work aims to study the effect of water deficit during bloom and grain pod-filling stages in two indeterminate soybean cultivar, Vtop and Nidera. The following physiological parameters were evaluated by means of daily CO2 assimilation rate (Ai, dynamic of carbohydrates in tissues, plant growth, grain yield and yield components. The study was conducted in a greenhouse with plants sown in tanks of 0.5 m3. Regardless of the phenological phase, water deficit reduced Ai, plant growth and number of pods and seeds per plant. The fact that grain yield was less affected by water deficit at bloom than at grain pod-filling stage was attributed to larger seeds found at bloom. In both treatments, a sharp reduction on carbohydrate content was found in leaves, stem and roots at the beginning of pod formation. The high amounts of carbohydrates remobilized for seed growth, along with the high values of Ai observed in well-watered plants, indicate that grain yield of soybeans is source rather than sink limited. On the other hand, in water deficit treatments, a new stimulus for carbohydrate storage was found in the leaves and stem at the beginning of grain maturity, suggesting that grain yield was limited by sink capacity.

  15. Yield and water use efficiency of deficit-irrigated maize in a semi ...

    African Journals Online (AJOL)

    Yield and water use efficiency of deficit-irrigated maize in a semi-arid region of Ethiopia. ... PROMOTING ACCESS TO AFRICAN RESEARCH. AFRICAN JOURNALS ONLINE ... African Journal of Food, Agriculture, Nutrition and Development.

  16. Contribution to the improvement of irrigation management practices through water - deficit irrigation

    International Nuclear Information System (INIS)

    Bazza, M.

    1995-01-01

    The study aimed at identifying irrigation management practices which could result in water savings through -water deficit irrigation. Two field experiments, one on wheat and the other on sugar beet, were conducted and consisted of refraining from supplying water during specific stages of the cycle so as to identy the period(s) during which water deficit would have a limited effect on crop production. In the case of wheat, high water deficit occurred during the early and during these stages was the most beneficial for the crop. However, one water application during the tillering stage allowed the yield to be lower only to that of the treatement with three irrigations. Irrigation during the stage of grain filling caused the kernel weight to be as high as under three irrigations. The lowest value corresponded to the treatement with one irrigation during grain filling and that under rainfed conditions. For sugar beet, when water stress was was applied early in the crop cycle, its effect could be almost entirely recovered with adequate watering during the rest of the growing season. On the opposite, good watering early in cycle, followed by a stress, resulted in the second lowest yield. Water deficit during the maturity stage had also a limited effect on yield. The most crucial periods for adequate watering were which correspond to late filiar development and root growth which coincided with the highest water requirements period. For the same amount of water savings through deficit irrigation, it was better to partition the stress throughout the cycle than during the critical stages of the crop. However, at the national level, it would have been more important to practice deficit irrigation and the irrigated area. For both crops, high yields as high as water - use efficiency values could have been obtained. 8 tabs; 5 refs ( Author )

  17. Physiological response and productivity of safflower lines under water deficit and rehydration.

    Science.gov (United States)

    Bortolheiro, Fernanda P A P; Silva, Marcelo A

    2017-01-01

    Water deficit is one of the major stresses affecting plant growth and productivity worldwide. Plants induce various morphological, physiological, biochemical and molecular changes to adapt to the changing environment. Safflower (Carthamus tinctorius L.), a potential oil producer, is highly adaptable to various environmental conditions, such as lack of rainfall and temperatures. The objective of this work was to study the physiological and production characteristics of six safflower lines in response to water deficit followed by rehydration. The experiment was conducted in a protected environment and consisted of 30 days of water deficit followed by 18 days of rehydration. A differential response in terms of photosynthetic pigments, electrolyte leakage, water potential, relative water content, grain yield, oil content, oil yield and water use efficiency was observed in the six lines under water stress. Lines IMA 04, IMA 10, IMA 14 showed physiological characteristics of drought tolerance, with IMA 14 and IMA 16 being the most productive after water deficit. IMA 02 and IMA 21 lines displayed intermediate characteristics of drought tolerance. It was concluded that the lines responded differently to water deficit stress, showing considerable genetic variation and influence to the environment.

  18. Physiological response and productivity of safflower lines under water deficit and rehydration

    Directory of Open Access Journals (Sweden)

    FERNANDA P.A.P. BORTOLHEIRO

    2017-12-01

    Full Text Available ABSTRACT Water deficit is one of the major stresses affecting plant growth and productivity worldwide. Plants induce various morphological, physiological, biochemical and molecular changes to adapt to the changing environment. Safflower (Carthamus tinctorius L., a potential oil producer, is highly adaptable to various environmental conditions, such as lack of rainfall and temperatures. The objective of this work was to study the physiological and production characteristics of six safflower lines in response to water deficit followed by rehydration. The experiment was conducted in a protected environment and consisted of 30 days of water deficit followed by 18 days of rehydration. A differential response in terms of photosynthetic pigments, electrolyte leakage, water potential, relative water content, grain yield, oil content, oil yield and water use efficiency was observed in the six lines under water stress. Lines IMA 04, IMA 10, IMA 14 showed physiological characteristics of drought tolerance, with IMA 14 and IMA 16 being the most productive after water deficit. IMA 02 and IMA 21 lines displayed intermediate characteristics of drought tolerance. It was concluded that the lines responded differently to water deficit stress, showing considerable genetic variation and influence to the environment.

  19. Effectiveness of Stability Indices for Bread Wheat Genotypes Selection to Water Deficit Tolerant

    Directory of Open Access Journals (Sweden)

    A Naderi

    2013-12-01

    Full Text Available In countries such as Iran which will be faced water deficit as the main challenge in the future and the food production is going to be dependent to water recourses, wheat water-deficit tolerant and adapted genotypes release is one of the most important strategies under such a condition. In order to study the adaptation and terminal water deficit stress tolerance, fifteen bread wheat lines and Chamran cultivar as the check were evaluated. This research was carried out at Ahvaz, Dezfool, Zabol and Darab, south warm region research stations, in 2007-08 and 2008-09, in two separated experiments (1-well-watered and 2- terminal water deficit stress, using complete randomized block design with three replications. Data were analyzed and genotypes response was evaluated based on tolerance indices. Results showed that the difference among stations, years, genotypes and double and triple effects of source variations were significant at 1% probability level. Mean grain yield was 4300 Kg/ha in first year, while grain yield increased significantly in second year and reached to 5692 Kg/ha. Mean grain yield were 5840 and 4591Kg/ha under well-watered and terminal water deficit stress conditions, respectively. Correlation coefficients among STI, GMP ،MP and K1STI were significant. Correlation coefficient between slop of linear regression of grain yield in response to drought stress intensity and grain yield under terminal water deficit stress was positively and, with K2STI, TOL and SSI was negatively significant. Grain yield index, (YIR the proportion of grain yield of each genotype to grand mean of grain yield of all genotypes was the most important components to define grain yield in stepwise regression under both experiment conditions. According to the results of this research and based on tolerance indices, lines No. 2, 14 and 15 were selected as the high potential- terminal water deficit stress tolerant genotypes.

  20. Climatic water deficit, tree species ranges, and climate change in Yosemite National Park

    Science.gov (United States)

    James A. Lutz; Jan W. van Wagtendonk; Jerry F. Franklin

    2010-01-01

    Modelled changes in climate water deficit between past, present and future climate scenarios suggest that recent past changes in forest structure and composition may accelerate in the future, with species responding individualistically to further declines in water availability. Declining water availability may disproportionately affect Pinus monticola...

  1. Responses to mild water deficit and rewatering differ among secondary metabolites but are similar among provenances within Eucalyptus species.

    Science.gov (United States)

    McKiernan, Adam B; Potts, Brad M; Brodribb, Timothy J; Hovenden, Mark J; Davies, Noel W; McAdam, Scott A M; Ross, John J; Rodemann, Thomas; O'Reilly-Wapstra, Julianne M

    2016-02-01

    Water deficit associated with drought can severely affect plants and influence ecological interactions involving plant secondary metabolites. We tested the effect of mild water deficit and rewatering on physiological, morphological and chemical traits of juvenile Eucalyptus globulus Labill. and Eucalyptus viminalis Labill. We also tested if responses of juvenile eucalypts to water deficit and rewatering varied within species using provenances across a rainfall gradient. Both species and all provenances were similarly affected by mild water deficit and rewatering, as only foliar abscisic acid levels differed among provenances during water deficit. Across species and provenances, water deficit decreased leaf water potential, above-ground biomass and formylated phloroglucinol compound concentrations, and increased condensed tannin concentrations. Rewatering reduced leaf carbon : nitrogen, and total phenolic and chlorogenic acid concentrations. Water deficit and rewatering had no effect on total oil or individual terpene concentrations. Levels of trait plasticity due to water deficit and rewatering were less than levels of constitutive trait variation among provenances. The overall uniformity of responses to the treatments regardless of native provenance indicates limited diversification of plastic responses when compared with the larger quantitative variation of constitutive traits within these species. These responses to mild water deficit may differ from responses to more extreme water deficit or to responses of juvenile/mature eucalypts growing at each locality. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. REPEATED MEASURES ANALYSIS OF CHANGES IN PHOTOSYNTHETIC EFFICIENCY IN SOUR CHERRY DURING WATER DEFICIT

    Directory of Open Access Journals (Sweden)

    Marija Viljevac

    2012-06-01

    Full Text Available The objective of this study was to investigate changes in photosynthetic efficiency applying repeated measures ANOVA using the photosynthetic performance index (PIABS of the JIP-test as a vitality parameter in seven genotypes of sour cherry (Prunus cerasus, L. during 10 days of continuous water deficit. Both univariate and multivariate ANOVA repeated measures revealed highly significant time effect (Days and its subsequent interactions with genotype and water deficit. However, the multivariate Pillai’s trace test detected the interaction Time × Genotype × Water deficit as not significant. According to the Tukey’s Studentized Range (HSD test, differences between the control and genotypes exposed to water stress became significant on the fourth day of the experiment, indicating that the plants on the average, began to lose their photosynthetic efficiency four days after being exposed to water shortage. It corroborates previous findings in other species that PIABS is very sensitive tool for detecting drought stress.

  3. Remobilization of carbon and nitrogen in wheat as influenced by postanthesis water deficits

    International Nuclear Information System (INIS)

    Palta, J.A.; Kobata, T.; Turner, N.C.; Fillery, I.R.

    1994-01-01

    Preanthesis stored C and N in wheat (Triticum aestivum L.) are important in a mediterranean climate because grain filling frequently depends on the remobilization of preanthesis assimilates. We determined the effect of the rate of development of postanthesis water deficits on the remobilization of C and N to the grain using stable isotopes of C and N accumulated in the plant during the vegetative phase. Plants were grown in pots with adequate water and under similar temperature and humidity conditions until anthesis, and then were transferred to two temperature and humidity regulated greenhouses, and watering was stopped. One greenhouse was maintained at minimum relative humidity of 80% and the other at 40%. Within 6 d of anthesis the rates of development of plant water deficits became different and for the first 19 d after anthesis they were 0.10 and 0.18 MPa d-1 for the high and low humidity regimes, respectively. Total grain C with fast development of water deficits was reduced by 24%, relative to the slow rate, because postanthesis C assimilation was reduced by 57%, while remobilization of preanthesis stored C was increased by 36%. Total grain N was not affected by the rate of development of water deficits because there was a greater retranslocation of preanthesis N with fast relative to slow development of water deficits and because there was a smaller loss of preanthesis N with fast development of water deficits. Fast development of water deficits reduced losses of preanthesis N from 25% to 6%. The absolute contributions of preanthesis C and N to the grain were 449 and 35 mg plant-1, respectively, with fast development of water deficits. These contributions accounted for 64 and 81% of the total grain C and N, respectively. The gain in grain 13C and 15N in the mainstem and Tiller 1 of plants exposed to rapid development of water deficits, arose not only from remobilization from the straw of those shoots, but also seemed to be supplemented by C and N

  4. Does morphological and anatomical plasticity during the vegetative stage make wheat more tolerant of water deficit stress than rice?

    NARCIS (Netherlands)

    Kadam, N.N.; Yin, X.; Bindraban, P.S.; Struik, P.C.; Jagadish, K.S.V.

    2015-01-01

    Water scarcity and the increasing severity of water deficit stress are major challenges to sustaining irrigated rice (Oryza sativa) production. Despite the technologies developed to reduce the water requirement, rice growth is seriously constrained under water deficit stress compared with other

  5. Rootstock control of scion transpiration and its acclimation to water deficit are controlled by different genes.

    Science.gov (United States)

    Marguerit, Elisa; Brendel, Oliver; Lebon, Eric; Van Leeuwen, Cornelis; Ollat, Nathalie

    2012-04-01

    The stomatal control of transpiration is one of the major strategies by which plants cope with water stress. Here, we investigated the genetic architecture of the rootstock control of scion transpiration-related traits over a period of 3 yr. The rootstocks studied were full sibs from a controlled interspecific cross (Vitis vinifera cv. Cabernet Sauvignon × Vitis riparia cv. Gloire de Montpellier), onto which we grafted a single scion genotype. After 10 d without stress, the water supply was progressively limited over a period of 10 d, and a stable water deficit was then applied for 15 d. Transpiration rate was estimated daily and a mathematical curve was fitted to its response to water deficit intensity. We also determined δ(13) C values in leaves, transpiration efficiency and water extraction capacity. These traits were then analysed in a multienvironment (year and water status) quantitative trait locus (QTL) analysis. Quantitative trait loci, independent of year and water status, were detected for each trait. One genomic region was specifically implicated in the acclimation of scion transpiration induced by the rootstock. The QTLs identified colocalized with genes involved in water deficit responses, such as those relating to ABA and hydraulic regulation. Scion transpiration rate and its acclimation to water deficit are thus controlled genetically by the rootstock, through different genetic architectures. © 2012 INRA. New Phytologist © 2012 New Phytologist Trust.

  6. Unraveling the involvement of ABA in the water deficit-induced modulation of nitrogen metabolism in Medicago truncatula seedlings.

    Science.gov (United States)

    Planchet, Elisabeth; Rannou, Olivier; Ricoult, Claudie; Limami, Anis M

    2011-07-01

    Effects of water deficit and/or abscisic acid (ABA) were investigated on early seedling growth of Medicago truncatula, and on glutamate metabolism under dark conditions. Water deficit (simulated by polyethylene glycol, PEG), ABA and their combination resulted in a reduction in growth rate of the embryo axis, and also in a synergistic increase of free amino acid (AA) content. However, the inhibition of water uptake retention induced by water deficit seemed to occur in an ABA-independent manner. Expression of several genes involved in glutamate metabolism was induced during water deficit, whereas ABA, in combination or not with PEG, repressed them. The only exception came from a gene encoding 1-pyrroline-5-carboxylate synthetase (P5CS) which appeared to be induced in an ABA-dependent manner under water deficit. Our results demonstrate clearly the involvement of an ABA-dependent and an ABA-independent regulatory system, governing growth and glutamate metabolism under water deficit.

  7. Nitrogen accumulation in lucerne (Medicago sativa L.) under water deficit stress

    OpenAIRE

    Vasileva Viliana; Vasilev Emil

    2013-01-01

    In order to study nitrogen accumulation in aboveground and root dry mass in lucerne (Medicago sativa L.) under water deficit stress, a pot experiment was carried out at the Institute of Forage Crops, Pleven, Bulgaria. The plants were grown under optimum water supply (75-80% FC) and 10-days water deficit stress was simulated at the stage of budding by interrupting the irrigation until soil moisture was reduced to 37-40% FC. Mineral nitrogen fertilization (ammonium nitrate) at the doses of 40, ...

  8. Individuals with chronic ankle instability exhibit dynamic postural stability deficits and altered unilateral landing biomechanics: A systematic review.

    Science.gov (United States)

    Simpson, Jeffrey D; Stewart, Ethan M; Macias, David M; Chander, Harish; Knight, Adam C

    2018-06-13

    To evaluate the literature regarding unilateral landing biomechanics and dynamic postural stability in individuals with and without chronic ankle instability (CAI). Four online databases (PubMed, ScienceDirect, Scopus, and SportDiscus) were searched from the earliest records to 31 January 2018, as well as reference sections of related journal articles, to complete the systematic search. Studies investigating the influence of CAI on unilateral landing biomechanics and dynamic postural stability were systematically reviewed and evaluated. Twenty articles met the criteria and were included in the systematic review. Individuals with CAI were found to have deficits in dynamic postural stability on the affected limb with medium to large effect sizes and altered lower extremity kinematics, most notably in the ankle and knee, with medium to large effect sizes. Additionally, greater loading rates and peak ground reaction forces, in addition to reductions in ankle muscle activity were also found in individuals with CAI during unilateral jump-landing tasks. Individuals with CAI demonstrate dynamic postural stability deficits, lower extremity kinematic alterations, and reduced neuromuscular control during unilateral jump-landings. These are likely factors that contribute recurrent lateral ankle sprain injuries during dynamic activity in individuals with CAI. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Explicit verbal memory impairments associated with brain functional deficits and morphological alterations in patients with generalized anxiety disorder.

    Science.gov (United States)

    Moon, Chung-Man; Yang, Jong-Chul; Jeong, Gwang-Woo

    2015-11-01

    Generalized anxiety disorder (GAD) is associated with brain function and morphological alterations. This study investigated explicit verbal memory impairment in patients with GAD in terms of brain functional deficits in combination with morphologic changes. Seventeen patients with GAD and 17 healthy controls matched for age, sex, and education level underwent high-resolution T1-weighted MRI and fMR imaging at 3 T during explicit verbal memory tasks with emotionally neutral and anxiety-inducing words. In response to the neutral words, the patients showed significantly lower activities in the regions of the hippocampus (Hip), middle cingulate gyrus (MCG), putamen (Pu) and head of the caudate nucleus (HCd) compared with healthy controls. In response to the anxiety-inducing words, the patients showed significantly higher activities in the ventrolateral prefrontal cortex and precentral gyrus. However, they showed lower activities in the Hip, MCG, Pu and HCd. In addition, patients with GAD showed a significant reduction in gray matter volumes, especially in the regions of the Hip, midbrain, thalamus, insula and superior temporal gyrus, compared with healthy controls. This study examined a small sample sizes in each of the groups, and there was no consideration of a medication effect on brain activity and volume changes. This study provides evidence for the association between brain functional deficits and morphometric alterations in an explicit verbal memory task for patients with GAD. This finding is helpful for understanding explicit verbal memory impairment in connection with GAD symptoms. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Water deficit stress effects on corn (Zea mays, L.) root: shoot ratio

    Science.gov (United States)

    A study was conducted at Akron, CO, USA, on a Weld silt loam in 2004 to quantify the effects of water deficit stress on corn (Zea mays, L.) root and shoot biomass. Corn plants were grown under a range of soil bulk density and water conditions caused by previous tillage, crop rotation, and irrigation...

  11. Peach response to water deficit in a semi-arid region

    Science.gov (United States)

    Paltineanu, C.; Septar, L.; Moale, C.; Nicolae, S.; Nicola, C.

    2013-09-01

    During three years a deficit irrigation experiment was performed on peach response under the semi-arid conditions of south-eastern Romania. Three sprinkler-irrigated treatments were investigated: fully irrigated, deficit irrigation treatment, and non-irrigated control treatment. Soil water content ranged between 60 and 76% of the plant available soil water capacity in fully irrigated, between 40 and 62% in deficit irrigation treatment, and between 30 and 45% in control. There were significant differences in fruit yield between the treatments. Irrigation water use efficiency was maximum in deficit irrigation treatment. Fruit yield correlated significantly with irrigation application. Total dry matter content, total solids content and titrable acidity of fruit were significantly different in the irrigated treatments vs. the control. Significant correlation coefficients were found between some fruit chemical components. For the possible future global warming conditions, when water use becomes increasingly restrictive, deficit irrigation will be a reasonable solution for water conservation in regions with similar soil and climate conditions.

  12. water deficit effects on morpho-physiologicals parameters in durum ...

    African Journals Online (AJOL)

    S. Chahbar

    1 sept. 2016 ... ABSTRACT. Various morpho-physiological characters r rate water loss, stomatal density, stomata genotypes under two hydrous conditions strategies develops by each genotype have present an appreciable variability intrasp related to the adaptation to the water defici for relative water content who is ...

  13. Response of Eucalyptus grandis trees to soil water deficits

    CSIR Research Space (South Africa)

    Dye, PJ

    1996-01-01

    Full Text Available , and sap flow rates revealed that prevention of soil water recharge resulted in only moderate drought stress. At Site 1, the trees abstracted water down to 8 m below the surface, whereas trees at Site 2 obtained most of their water from depths below 8 m. I...

  14. [Estimating the impacts of future climate change on water requirement and water deficit of winter wheat in Henan Province, China].

    Science.gov (United States)

    Ji, Xing-jie; Cheng, Lin; Fang, Wen-song

    2015-09-01

    Based on the analysis of water requirement and water deficit during development stage of winter wheat in recent 30 years (1981-2010) in Henan Province, the effective precipitation was calculated using the U.S. Department of Agriculture Soil Conservation method, the water requirement (ETC) was estimated by using FAO Penman-Monteith equation and crop coefficient method recommended by FAO, combined with the climate change scenario A2 (concentration on the economic envelopment) and B2 ( concentration on the sustainable development) of Special Report on Emissions Scenarios (SRES) , the spatial and temporal characteristics of impacts of future climate change on effective precipitation, water requirement and water deficit of winter wheat were estimated. The climatic impact factors of ETc and WD also were analyzed. The results showed that under A2 and B2 scenarios, there would be a significant increase in anomaly percentage of effective precipitation, water requirement and water deficit of winter wheat during the whole growing period compared with the average value from 1981 to 2010. Effective precipitation increased the most in 2030s under A2 and B2 scenarios by 33.5% and 39.2%, respectively. Water requirement increased the most in 2010s under A2 and B2 scenarios by 22.5% and 17.5%, respectively, and showed a significant downward trend with time. Water deficit increased the most under A2 scenario in 2010s by 23.6% and under B2 scenario in 2020s by 13.0%. Partial correlation analysis indicated that solar radiation was the main cause for the variation of ETc and WD in future under A2 and B2 scenarios. The spatial distributions of effective precipitation, water requirement and water deficit of winter wheat during the whole growing period were spatially heterogeneous because of the difference in geographical and climatic environments. A possible tendency of water resource deficiency may exist in Henan Province in the future.

  15. Study of glass alteration mechanisms in cement waters

    International Nuclear Information System (INIS)

    Depierre, S.

    2012-01-01

    In the French deep geological repository concept, intermediate-level vitrified waste packages could be disposed of concrete medium. Chemical composition and pH of the interstitial leaching water are expected to influence the chemical durability of glass. Investigations have thus been carried out to study glass dissolution mechanisms and kinetics in contact with cement waters. Three cement pore waters were studied: the first two correspond to two stages of the Portland cement aging and the third corresponds to equilibrium with a low pH concrete. The S/V ratio (glass-surface-area-to-solution-volume ratio) and the chemistry of cement waters are the two main parameters that control glass alteration mechanisms. If the leaching flow from the glass allows a degree of supersaturation to be reached and maintained which leads to nucleation of secondary phases, then precipitation of these phases drives glass dissolution. At a very low S/V ratio, the calcium uptake into the alteration layer increases its passivating properties. Conversely, at a high S/V ratio, the calcium precipitates as cementitious phases consuming elements which form the alteration layer. The glass dissolution is maintained at a high rate. This study contributes to highlighting the beneficial role of low pH cement in glass alteration, and is a first step towards understanding the mechanisms between the glass and the cement medium. (author) [fr

  16. Cognitive Deficits Associated with Nav1.1 Alterations: Involvement of Neuronal Firing Dynamics and Oscillations.

    Directory of Open Access Journals (Sweden)

    Alex C Bender

    Full Text Available Brain oscillations play a critical role in information processing and may, therefore, be essential to uncovering the mechanisms of cognitive impairment in neurological disease. In Dravet syndrome (DS, a mutation in SCN1A, coding for the voltage-gated sodium channel Nav1.1, is associated with severe cognitive impairment and seizures. While seizure frequency and severity do not correlate with the extent of impairment, the slowing of brain rhythms may be involved. Here we investigate the role of Nav1.1 on brain rhythms and cognition using RNA interference. We demonstrate that knockdown of Nav1.1 impairs fast- and burst-firing properties of neurons in the medial septum in vivo. The proportion of neurons that fired phase-locked to hippocampal theta oscillations was reduced, and medial septal regulation of theta rhythm was disrupted. During a working memory task, this deficit was characterized by a decrease in theta frequency and was negatively correlated with performance. These findings suggest a fundamental role for Nav1.1 in facilitating fast-firing properties in neurons, highlight the importance of precise temporal control of theta frequency for working memory, and imply that Nav1.1 deficits may disrupt information processing in DS via a dysregulation of brain rhythms.

  17. Effect of Water Deficit on Water Relations, Photosynthesis and Osmolytes Accumulation of Salvia leriifolia Benth

    Directory of Open Access Journals (Sweden)

    M Dashti

    2015-04-01

    Full Text Available In order to investigate the effect of water deficit (WD stress on water relations and some physiological characteristics of Salvia leriifolia Bench., a greenhouse experiment was conducted in completely randomized design with three replications. Irrigation treatments were fully irrigated as control (-0.035 MPa, mild stress (-0.138 MPa, moderate stress (-0.516 MPa and severe stress (-1.92 MPa. One set of stressed plants were kept constantly in different levels of matric potentials and the other set (Recovery treatments irrigated to maximum water holding capacity after soil water was depleted in each stress level. Measured parameters were leaf relative water content (LRWC, membrane stability index (MSI, prolin and soluble carbohydrates content, gas exchange parameters, Intrinsic Water Use Efficiency (WUEi and Intrinsic Gas Exchange Efficiency (GEEi. The results showed that LRWC and MSI in control plants significantly (P≤0.05 were lower than mild stress but decreased 17.3% and 21% respectively in severe stress compared to control. Soluble carbohydrates content was increased with increasing WD levels but it was only significant with control plants. There was strong negative correlation between LRWC and proline content (r= -0.99***, therefore leaves proline content increased twice (1023 nmol per g fresh weight at -1.92 Mpa compared to control. Results also indicated that gas exchange parameters were not significantly difference in mild WD against control but with decreasing soil matric potential to -1.92 Mpa, net photosynthesis rate (A, transpiration rate and stomatal conductance (gs decreased 52, 62 and 75 % respectively. In contrast WUEi and GEE increased 35 and 92% respectively.

  18. Research Review: Dopamine Transfer Deficit: A Neurobiological Theory of Altered Reinforcement Mechanisms in ADHD

    Science.gov (United States)

    Tripp, Gail; Wickens, Jeff R.

    2008-01-01

    This review considers the hypothesis that changes in dopamine signalling might account for altered sensitivity to positive reinforcement in children with ADHD. The existing evidence regarding dopamine cell activity in relation to positive reinforcement is reviewed. We focus on the anticipatory firing of dopamine cells brought about by a transfer…

  19. Physiological and biochemical responses involved in water deficit tolerance of nitrogen-fixing Vicia faba

    Science.gov (United States)

    Kabbadj, Ablaa; Makoudi, Bouchra; Mouradi, Mohammed; Frendo, Pierre; Ghoulam, Cherki

    2017-01-01

    Climate change is increasingly impacting the water deficit over the world. Because of drought and the high pressure of the rising human population, water is becoming a scarce and expensive commodity, especially in developing countries. The identification of crops presenting a higher acclimation to drought stress is thus an important objective in agriculture. The present investigation aimed to assess the adaptation of three Vicia faba genotypes, Aguadulce (AD), Luz d’Otonio (LO) and Reina Mora (RM) to water deficit. Multiple physiological and biochemical parameters were used to analyse the response of the three genotypes to two soil water contents (80% and 40% of field capacity). A significant lower decrease in shoot, root and nodule dry weight was observed for AD compared to LO and RM. The better growth performance of AD was correlated to higher carbon and nitrogen content than in LO and RM under water deficit. Leaf parameters such as relative water content, mass area, efficiency of photosystem II and chlorophyll and carotenoid content were significantly less affected in AD than in LO and RM. Significantly higher accumulation of proline was correlated to the higher performance of AD compared to LO and RM. Additionally, the better growth of AD genotype was related to an important mobilisation of antioxidant enzyme activities such as ascorbate peroxidase and catalase. Taken together, these results allow us to suggest that AD is a water deficit tolerant genotype compared to LO and RM. Our multiple physiological and biochemical analyses show that nitrogen content, leaf proline accumulation, reduced leaf hydrogen peroxide accumulation and leaf antioxidant enzymatic activities (ascorbate peroxidase, guaiacol peroxidase, catalase and polyphenol oxidase) are potential biological markers useful to screen for water deficit resistant Vicia faba genotypes. PMID:29281721

  20. Physiological and biochemical responses involved in water deficit tolerance of nitrogen-fixing Vicia faba.

    Directory of Open Access Journals (Sweden)

    Ablaa Kabbadj

    Full Text Available Climate change is increasingly impacting the water deficit over the world. Because of drought and the high pressure of the rising human population, water is becoming a scarce and expensive commodity, especially in developing countries. The identification of crops presenting a higher acclimation to drought stress is thus an important objective in agriculture. The present investigation aimed to assess the adaptation of three Vicia faba genotypes, Aguadulce (AD, Luz d'Otonio (LO and Reina Mora (RM to water deficit. Multiple physiological and biochemical parameters were used to analyse the response of the three genotypes to two soil water contents (80% and 40% of field capacity. A significant lower decrease in shoot, root and nodule dry weight was observed for AD compared to LO and RM. The better growth performance of AD was correlated to higher carbon and nitrogen content than in LO and RM under water deficit. Leaf parameters such as relative water content, mass area, efficiency of photosystem II and chlorophyll and carotenoid content were significantly less affected in AD than in LO and RM. Significantly higher accumulation of proline was correlated to the higher performance of AD compared to LO and RM. Additionally, the better growth of AD genotype was related to an important mobilisation of antioxidant enzyme activities such as ascorbate peroxidase and catalase. Taken together, these results allow us to suggest that AD is a water deficit tolerant genotype compared to LO and RM. Our multiple physiological and biochemical analyses show that nitrogen content, leaf proline accumulation, reduced leaf hydrogen peroxide accumulation and leaf antioxidant enzymatic activities (ascorbate peroxidase, guaiacol peroxidase, catalase and polyphenol oxidase are potential biological markers useful to screen for water deficit resistant Vicia faba genotypes.

  1. Gray Matter Alterations in Adults with Attention-Deficit/Hyperactivity Disorder Identified by Voxel Based Morphometry

    Science.gov (United States)

    Seidman, Larry J.; Biederman, Joseph; Liang, Lichen; Valera, Eve M.; Monuteaux, Michael C.; Brown, Ariel; Kaiser, Jonathan; Spencer, Thomas; Faraone, Stephen V.; Makris, Nikos

    2014-01-01

    Background Gray and white matter volume deficits have been reported in many structural magnetic resonance imaging (MRI) studies of children with attention-deficit/hyperactivity disorder (ADHD); however, there is a paucity of structural MRI studies of adults with ADHD. This study used voxel based morphometry and applied an a priori region of interest approach based on our previous work, as well as from well-developed neuroanatomical theories of ADHD. Methods Seventy-four adults with DSM-IV ADHD and 54 healthy control subjects comparable on age, sex, race, handedness, IQ, reading achievement, frequency of learning disabilities, and whole brain volume had an MRI on a 1.5T Siemens scanner. A priori region of interest hypotheses focused on reduced volumes in ADHD in dorsolateral prefrontal cortex, anterior cingulate cortex, caudate, putamen, inferior parietal lobule, and cerebellum. Analyses were carried out by FSL-VBM 1.1. Results Relative to control subjects, ADHD adults had significantly smaller gray matter volumes in parts of six of these regions at p ≤ .01, whereas parts of the dorsolateral prefrontal cortex and inferior parietal lobule were significantly larger in ADHD at this threshold. However, a number of other regions were smaller and larger in ADHD (especially fronto-orbital cortex) at this threshold. Only the caudate remained significantly smaller at the family-wise error rate. Conclusions Adults with ADHD have subtle volume reductions in the caudate and possibly other brain regions involved in attention and executive control supporting frontostriatal models of ADHD. Modest group brain volume differences are discussed in the context of the nature of the samples studied and voxel based morphometry methodology. PMID:21183160

  2. The photosynthetic response of tobacco plants overexpressing ice plant aquaporin McMIPB to a soil water deficit and high vapor pressure deficit.

    Science.gov (United States)

    Kawase, Miki; Hanba, Yuko T; Katsuhara, Maki

    2013-07-01

    We investigated the photosynthetic capacity and plant growth of tobacco plants overexpressing ice plant (Mesembryanthemum crystallinum L.) aquaporin McMIPB under (1) a well-watered growth condition, (2) a well-watered and temporal higher vapor pressure deficit (VPD) condition, and (3) a soil water deficit growth condition to investigate the effect of McMIPB on photosynthetic responses under moderate soil and atmospheric humidity and water deficit conditions. Transgenic plants showed a significantly higher photosynthesis rate (by 48 %), higher mesophyll conductance (by 52 %), and enhanced growth under the well-watered growth condition than those of control plants. Decreases in the photosynthesis rate and stomatal conductance from ambient to higher VPD were slightly higher in transgenic plants than those in control plants. When plants were grown under the soil water deficit condition, decreases in the photosynthesis rate and stomatal conductance were less significant in transgenic plants than those in control plants. McMIPB is likely to work as a CO2 transporter, as well as control the regulation of stomata to water deficits.

  3. Effects of voluntary and treadmill exercise on spontaneous withdrawal signs, cognitive deficits and alterations in apoptosis-associated proteins in morphine-dependent rats.

    Science.gov (United States)

    Mokhtari-Zaer, Amin; Ghodrati-Jaldbakhan, Shahrbanoo; Vafaei, Abbas Ali; Miladi-Gorji, Hossein; Akhavan, Maziar M; Bandegi, Ahmad Reza; Rashidy-Pour, Ali

    2014-09-01

    Chronic exposure to morphine results in cognitive deficits and alterations of apoptotic proteins in favor of cell death in the hippocampus, a brain region critically involved in learning and memory. Physical activity has been shown to have beneficial effects on brain health. In the current work, we examined the effects of voluntary and treadmill exercise on spontaneous withdrawal signs, the associated cognitive defects, and changes of apoptotic proteins in morphine-dependent rats. Morphine dependence was induced through bi-daily administrations of morphine (10mg/kg) for 10 days. Then, the rats were trained under two different exercise protocols: mild treadmill exercise or voluntary wheel exercise for 10 days. After exercise training, their spatial learning and memory and aversive memory were examined by a water maze and by an inhibitory avoidance task, respectively. The expression of the pro-apoptotic protein Bax and the anti-apoptotic protein Bcl-2 in the hippocampus were determined by immunoblotting. We found that chronic exposure to morphine impaired spatial and aversive memory and remarkably suppressed the expression of Bcl-2, but Bax expression remained constant. Both voluntary and treadmill exercise alleviated memory impairment, increased the expression of Bcl-2 protein, and only the later suppressed the expression of Bax protein in morphine-dependent animals. Moreover, both exercise protocols diminished the occurrence of spontaneous morphine withdrawal signs. Our findings showed that exercise reduces the spontaneous morphine-withdrawal signs, blocks the associated impairment of cognitive performance, and overcomes morphine-induced alterations in apoptotic proteins in favor of cell death. Thus, exercise may be a useful therapeutic strategy for cognitive and behavioral deficits in addict individuals. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. The alteration of gray matter volume in children with mental retardation: the differences between the patients presented with operation deficit predominantly and those presented with language deficit mainly

    International Nuclear Information System (INIS)

    Yuan Xinyu; Jiang Xuexiang; Jin Chunhua; Zhang Yuanchao; Bai Zhenhua; Yi Xiaoli; Xiao Jiangxi

    2012-01-01

    Objective: To detect the differences of grey matter volume between the patients with mental retardation (MR) presented clinically as operation deficit (OD) or as language deficit (LD) and the children with typical normal development using optimal VBM. The developmental connections between brain gray matter and language or operation skills were examined. Methods: Magnetic resonance imaging was obtained from 9 children with mental retardation presented as OD predominantly and 11 children with mental retardation presented as LD mainly, as well as the age-matched control group (11 and 14 normal children,respectively) on a 1.5 T scanner. Voxel-based morphometry analysis with an optimization of spatial segmentation and normalization procedures was applied to compare the volume of grey matter between the two groups (OD VS.control; LD VS.control). Statistically, the total and local gray matter volumes were compared between the two groups with t test. Results: The total gray matter volume of OD group was [(1.030 ± 0.078) × 10 6 mm 3 ]. Compared to that of controls [(0.984 ± 0.058) × 10 6 mm 3 ], it was increased significantly (t=-2.6, P<0.05). And the gray matter volume in the posterior cingulated gyrus, left superior prefrontal gyrus, left cuneus, left middle prefrontal gyrus and the body of left caudate nucleus showed significantly increased. Meanwhile, the total gray matter volume of the MR children presented as LD [(1.002 ± 0.068) × 10 6 mm 3 ] showed significantly increased(t=-3.0, P<0.05) compared with that of control group [(0.957 ±0.057) × 10 6 mm 3 ]. The gray matter volume in bilateral thalami, the left inferior temporal gyrus,the left inferior frontal gyrus, and the left cerebellum of the LD group was more than that of normal children. Conclusion: As revealed by VBM, there are differences in alterations of gray matter volume between MR children presented with OD and with LD relative to control. (authors)

  5. Laminar thickness alterations in the fronto-parietal cortical mantle of patients with attention-deficit/hyperactivity disorder.

    Directory of Open Access Journals (Sweden)

    Elseline Hoekzema

    Full Text Available Although Attention-Deficit/Hyperactivity Disorder (ADHD was initially regarded as a disorder exclusive to childhood, nowadays its prevalence in adulthood is well established. The development of novel techniques for quantifying the thickness of the cerebral mantle allows the further exploration of the neuroanatomical profiles underlying the child and adult form of the disorder. To examine the cortical mantle in children and adults with ADHD, we applied a vertex-wise analysis of cortical thickness to anatomical brain MRI scans acquired from children with (n = 43 and without ADHD (n = 41, as well as a group of adult neurotypical individuals (n = 31, adult patients with a history of stimulant treatment (n = 31 and medication-naïve adults with ADHD (n = 24. We observed several clusters of reduced laminar cortical thickness in ADHD patients in comparison to neurotypical individuals. These differences were primarily located in the dorsal attention network, including the bilateral inferior and superior parietal cortex and a section of the frontal cortex (centered on the superior frontal and precentral gyrus bilaterally. Further laminar thickness deficits were observed in the bilateral orbitofrontal cortex and medial occipital cortex. The deficits in the cortical surface were especially pronounced in the child sample, while adult patients showed a more typical laminar thickness across the cerebral mantle. These findings show that the neuroanatomical profile of ADHD, especially the childhood form of the disorder, involves robust alterations in the cortical mantle, which are most prominent in brain regions subserving attentional processing.

  6. Effect of water deficit on growth and photosynthetic characteristics of ...

    African Journals Online (AJOL)

    Administrator

    2011-09-26

    Sep 26, 2011 ... Danièle Clavel, Omar Diouf, Jean L, Khalfaoui, SB (2006). Genotypes ... chlorophyll fluorescence parameters and carbon isotope discrimination of ... oxygen evolution at low water potential in leaf discs lacking an epidermis.

  7. Working to reverse a water deficit | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... and Yugoslavia, Bataineh began work for the Ministry of Water and Irrigation in 1975. ... cubic metres of wastewater treated in Jordan can only be used in agriculture ... Consequently, the ministry has started to improve existing wastewater ...

  8. Rate and duration of seed filling and yield of soybean affected by water and radiation deficits

    Directory of Open Access Journals (Sweden)

    Kazem GHASSEMI-GOLEZANI

    2015-11-01

    Full Text Available Seed filling and yield of soybean under water and radiation deficits were investigated during 2011 and 2012. Treatments were irrigations (I1, I2, I3 and I4 for irrigation after 60, 90, 120 and 150 mm evaporation from class A pan, respectively in main plots and light interceptions (L1: 100 %, L2: 65 % and L3: 25 % sunlight in sub-plots. Seeds per plant under I1 and I2 decreased, but under I3 and I4 increasedas a result of radiation deficit. Maximum seed weight and seed filling duration of plants under 25 % light interception (L3 were higher than those under full sunlight (L1 and 65 % light interception (L2. In contrast, plants under full sunlight had the highest seed filling rate, particularly under water stress. Seed filling duration under severe light deficit (L3 was about 9 days longer than that under full sunlight (L1, leading to 15.8 % enhancement in maximum seed weight. Decreasing seed yield of soybean under well watering and mild water stress and improving it under moderate and severe water deficit due to low solar radiation are directly related with changes in seed filling duration and consequently in seed weight and number of seeds per plant under these conditions.

  9. Flight initiation and maintenance deficits in flies with genetically altered biogenic amine levels

    OpenAIRE

    Brembs, Björn; Christiansen, F.; Pflüger, J.; Duch, C.

    2007-01-01

    Insect flight is one of the fastest, most intense and most energy-demanding motor behaviors. It is modulated on multiple levels by the biogenic amine octopamine. Within the CNS, octopamine acts directly on the flight central pattern generator, and it affects motivational states. In the periphery, octopamine sensitizes sensory receptors, alters muscle contraction kinetics, and enhances flight muscle glycolysis. This study addresses the roles for octopamine and its precursor tyramine in flight ...

  10. Influence of water deficit on transpiration and radiation use efficiency of chickpea (Cicer arietinum L.)

    International Nuclear Information System (INIS)

    Singh, P.; Sri Rama, Y.V.

    1989-01-01

    Information on the relationship between biomass production, radiation use and water use of chickpea (Cicer arietinum L.) is essential to estimate biomass production in different water regimes. Experiments were conducted during three post-rainy seasons on a Vertisol (a typic pallustert) to study the effect of water deficits on radiation use, radiation use efficiency (RUE), transpiration and transpiration efficiency (TE) of chickpea. Different levels of soil water availability were created, either by having irrigated and non-irrigated plots or using a line source. Biomass production was linearly related to both cumulative intercepted solar radiation and transpiration in both well watered and water deficit treatments. Soil water availability did not affect RUE (total dry matter produced per unit of solar radiation interception) when at least 30% of extractable soil water (ESW) was present in the rooting zone, but below 30% ESW, RUE decreased linearly with the decrease in soil water content. RUE was also significantly correlated (R 2 = 0.61, P < 0.01) with the ratio of actual to potential transpiration (T/Tp) and it declined curvilinearly with the decrease in T/Tp. TE decreased with the increase in saturation deficit (SD) of air. Normalization of TE with SD gave a conservative value of 4.8 g kPa kg −1 . To estimate biomass production of chickpea in different environments, we need to account for the effect of plant water deficits on RUE in a radiation-based model and the effect of SD on TE in a transpiration-based model. (author)

  11. Water deficit and water surplus maps for Brazil, based on FAO Penman-Monteith potential evapotranspiration

    Directory of Open Access Journals (Sweden)

    Ronalton Evandro Machado

    2008-12-01

    Full Text Available The climatological water balance (CWB proposed by Thornthwaite and Mather (1957 is a useful tool for agricultural planning. This method requires the soil water holding capacity (SWHC, rainfall (R and potential evapotranspiration (PET data as input. Among the methods used to estimate PET, the one proposed by Thornthwaite (1948 is the simplest and the most used in Brazil, however it presents limitations of use, which is caused by its empirical relationships. When Thornthwaite PET method is used into the CWB, the errors associated to PET are transferred to the output variables, mainly water deficit (WD and water surplus (WS. As all maps of WD and WS for Brazil are based on Thornthwaite PET, the objective of this study was to produce new maps of these variables considering Penman-Monteith PET. For this purpose, monthly normal climate data base (1961-1990 from Brazilian Meteorological Service (INMET, with 219 locations in all country, was used. PET data were estimated by Thornthwaite (TH and FAO Penman-Monteith (PM methods. PET, from both methods, and R data were used to estimate the CWB for a SWHC of 100 mm, having as results actual ET (AET, WD and WS. Results obtained with PET from the two methods were compared by regression analysis. The results showed that TH method underestimated annual PM PET by 13% in 84% of the places. Such underestimation also led to AET and WD underestimations of 7% (in 69% of places and 40% (in 83% of places, respectively. For WS, the use of TH PET data in the CWB resulted in overestimations of about 80% in 78% of places. The differences observed in the CWB variables resulted in changes in the maps of WD and WS for Brazil. These new maps, based on PM PET, provide more accurate information, mainly for agricultural and hydrological planning and irrigation and drainage projects purposes.

  12. Altered neural connectivity during response inhibition in adolescents with attention-deficit/hyperactivity disorder and their unaffected siblings.

    Science.gov (United States)

    van Rooij, Daan; Hartman, Catharina A; Mennes, Maarten; Oosterlaan, Jaap; Franke, Barbara; Rommelse, Nanda; Heslenfeld, Dirk; Faraone, Stephen V; Buitelaar, Jan K; Hoekstra, Pieter J

    2015-01-01

    Response inhibition is one of the executive functions impaired in attention-deficit/hyperactivity disorder (ADHD). Increasing evidence indicates that altered functional and structural neural connectivity are part of the neurobiological basis of ADHD. Here, we investigated if adolescents with ADHD show altered functional connectivity during response inhibition compared to their unaffected siblings and healthy controls. Response inhibition was assessed using the stop signal paradigm. Functional connectivity was assessed using psycho-physiological interaction analyses applied to BOLD time courses from seed regions within inferior- and superior frontal nodes of the response inhibition network. Resulting networks were compared between adolescents with ADHD (N = 185), their unaffected siblings (N = 111), and controls (N = 125). Control subjects showed stronger functional connectivity than the other two groups within the response inhibition network, while subjects with ADHD showed relatively stronger connectivity between default mode network (DMN) nodes. Stronger connectivity within the response inhibition network was correlated with lower ADHD severity, while stronger connectivity with the DMN was correlated with increased ADHD severity. Siblings showed connectivity patterns similar to controls during successful inhibition and to ADHD subjects during failed inhibition. Additionally, siblings showed decreased connectivity with the primary motor areas as compared to both participants with ADHD and controls. Subjects with ADHD fail to integrate activation within the response inhibition network and to inhibit connectivity with task-irrelevant regions. Unaffected siblings show similar alterations only during failed stop trials, as well as unique suppression of motor areas, suggesting compensatory strategies. These findings support the role of altered functional connectivity in understanding the neurobiology and familial transmission of ADHD.

  13. The Response of Rice Root to Time Course Water Deficit Stress-Two Dimensional Electrophoresis Approach

    Directory of Open Access Journals (Sweden)

    Mahmood Toorchi

    2015-11-01

    Full Text Available Rice (Oryza sativa L. is the staple food of more than half of the population worldwide. Water deficit stress is one of the harsh limiting factors for successful production of crops. Rice during its growing period comes a cross different environmental hazards like drought stress. Recent advance in molecular physiology are promising for more progress in increasing rice yield by identification of novel candidate proteins for drought tolerance. To investigate the effect of water deficit on rice root protein expression pattern, an experiment was conducted in completely randomize design with four replications. With holding water for 24, 36 and 48 hours along with control constituted the experimental treatments. The experiment was conducted in growth chamber under controlled condition and root samples, after stress imposition, were harvested for two-dimensional electrophorese (2-DE. Proteome analysis of root tissue by 2-DE indicated that out of 135 protein spots diagnosed by Coomassie blue staining, 14 spots showed significant expression change under water deficit condition, seven of them at 1% and the other seven at 5% probability levels. Differentially changed proteins were taken into account for search in data bank using isoelectric point and molecular weight to identify the most probable responsive proteins. Up- regulation of ferredoxin oxidoreductase at first 24 hour after applying stress indicates the main role of this protein in reducing water deficit stress effects. On the other hand ribosomal proteins, GAP-3 and ATP synthase were down regulated under water deficit stress. Fructose 1,6-bisphosphate aldolase, glucose- 6-phosphate dehydrogenase and chitinase down regulated up to 36 h of stress imposition but, were later up- regulated by prolonging stress up to 48 h. It could be inferred the plant tries to decrease the effect of oxidative stress.

  14. Functionally relevant climate variables for arid lands: Aclimatic water deficit approach for modelling desert shrub distributions

    Science.gov (United States)

    Thomas E. Dilts; Peter J. Weisberg; Camie M. Dencker; Jeanne C. Chambers

    2015-01-01

    We have three goals. (1) To develop a suite of functionally relevant climate variables for modelling vegetation distribution on arid and semi-arid landscapes of the Great Basin, USA. (2) To compare the predictive power of vegetation distribution models based on mechanistically proximate factors (water deficit variables) and factors that are more mechanistically removed...

  15. An evaluation of water deficit tolerance screening in pigmented indica rice genotypes

    International Nuclear Information System (INIS)

    Chutipaijit, S.; Sompornpailin, K.

    2011-01-01

    Eight pigmented genotypes of indica subspecies were geminated and then treated by mannitol-induced water deficit stress. A change of growth characteristics, photosynthetic pigments, lipid peroxidation, DNA content, proline content and anthocyanin accumulation in stressed seedling (100 mM mannitol) and control plant (0 mM mannitol) were calculated. Growth performances, photosynthetic pigment concentrations , and DNA contents in all rice genotypes were dropped whereas proline, anthocyanin contents and the lipid peroxidation levels were enriched. The stabilization in total photosynthetic pigment concentrations of stressed-seedlings were positively correlated to the proline or anthocyanin accumulation. In contrast, MDA content, the increases in the percentages of drought-stressed seedlings were negatively correlated to the proline or anthocyanin accumulation. The changes in biochemical, physiological and growth parameters were subjected to Wards cluster analysis for water deficit tolerance. These cultivars could be classified into two groups, water deficit sensitive, SY, KD, KLD and TD49 and water deficit tolerance, KS, KK1, KK2 and BSR. (author)

  16. Diallelic analysis to obtain cowpea (Vigna unguiculata L. Walp.) populations tolerant to water deficit.

    Science.gov (United States)

    Rodrigues, E V; Damasceno-Silva, K J; Rocha, M M; Bastos, E A

    2016-05-13

    The purpose of this study was to identify parents and obtain segregating populations of cowpea (Vigna unguiculata L. Walp.) with the potential for tolerance to water deficit. A full diallel was performed with six cowpea genotypes, and two experiments were conducted in Teresina, PI, Brazil in 2011 to evaluate 30 F2 populations and their parents, one under water deficit and the other under full irrigation. A triple-lattice experimental design was used, with six 2-m-long rows in each plot. Sixteen plants were sampled per plot. The data were subjected to analysis of variance, and general and specific combining ability estimates were obtained based on the means. Additive effects were more important than non-additive effects, and maternal inheritance had occurred. The genotypes BRS Xiquexique, Pingo de Ouro-1-2, and MNC99-510F-16-1 were the most promising for use in selection programs aimed at water deficit tolerance. The hybrid combinations Pingo de Ouro-1-2 x BRS Xiquexique, BRS Xiquexique x Santo Inácio, CNCx 698-128G x MNC99-510F-16-1, Santo Inácio x CNCx 698-128G, MNC99-510F-16-1 x BRS Paraguaçu, MNC99- 510F-16-1 x Pingo de Ouro-1-2, and MNC99-510F-16-1 x BRS Xiquexique have the potential to increase grain production and tolerate water deficit.

  17. The functional dependence of canopy conductance on water vapor pressure deficit revisited

    NARCIS (Netherlands)

    Fuchs, Marcel; Stanghellini, Cecilia

    2018-01-01

    Current research seeking to relate between ambient water vapor deficit (D) and foliage conductance (gF) derives a canopy conductance (gW) from measured transpiration by inverting the coupled transpiration model to yield gW = m − n ln(D) where m and n are fitting parameters. In contrast, this paper

  18. Effect of water deficit on Argan tree seedlings (Argania spinosa L ...

    African Journals Online (AJOL)

    USER

    2015-03-17

    Mar 17, 2015 ... The Argan tree, Argania spinosa L., Skeels, is an endemic species in North-West Africa perfectly adapted to aridity and drought. It is in this context that we studied the physiological impact of water deficit on the Argan tree seedlings for eight weeks at a field capacity of 30%. The obtained results reveal.

  19. Deficit irrigation and sustainable water-resource strategies in agriculture for China's food security.

    Science.gov (United States)

    Du, Taisheng; Kang, Shaozhong; Zhang, Jianhua; Davies, William J

    2015-04-01

    More than 70% of fresh water is used in agriculture in many parts of the world, but competition for domestic and industrial water use is intense. For future global food security, water use in agriculture must become sustainable. Agricultural water-use efficiency and water productivity can be improved at different points from the stomatal to the regional scale. A promising approach is the use of deficit irrigation, which can both save water and induce plant physiological regulations such as stomatal opening and reproductive and vegetative growth. At the scales of the irrigation district, the catchment, and the region, there can be many other components to a sustainable water-resources strategy. There is much interest in whether crop water use can be regulated as a function of understanding of physiological responses. If this is the case, then agricultural water resources can be reallocated to the benefit of the broader community. We summarize the extent of use and impact of deficit irrigation within China. A sustainable strategy for allocation of agricultural water resources for food security is proposed. Our intention is to build an integrative system to control crop water use during different cropping stages and actively regulate the plant's growth, productivity, and development based on physiological responses. This is done with a view to improving the allocation of limited agricultural water resources. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  20. Deficit irrigation and sustainable water-resource strategies in agriculture for China’s food security

    Science.gov (United States)

    Du, Taisheng; Kang, Shaozhong; Zhang, Jianhua; Davies, William J.

    2015-01-01

    More than 70% of fresh water is used in agriculture in many parts of the world, but competition for domestic and industrial water use is intense. For future global food security, water use in agriculture must become sustainable. Agricultural water-use efficiency and water productivity can be improved at different points from the stomatal to the regional scale. A promising approach is the use of deficit irrigation, which can both save water and induce plant physiological regulations such as stomatal opening and reproductive and vegetative growth. At the scales of the irrigation district, the catchment, and the region, there can be many other components to a sustainable water-resources strategy. There is much interest in whether crop water use can be regulated as a function of understanding of physiological responses. If this is the case, then agricultural water resources can be reallocated to the benefit of the broader community. We summarize the extent of use and impact of deficit irrigation within China. A sustainable strategy for allocation of agricultural water resources for food security is proposed. Our intention is to build an integrative system to control crop water use during different cropping stages and actively regulate the plant’s growth, productivity, and development based on physiological responses. This is done with a view to improving the allocation of limited agricultural water resources. PMID:25873664

  1. Phenotypic plasticity in plants of Lippia dulcis (verbenaceae) subjected to water deficit

    International Nuclear Information System (INIS)

    Villamizar Cujar, Javier Mauricio; Rodriguez Lopez, Nelson Facundo; Tezara Fernandez, Wilmer

    2012-01-01

    Phenotypic plasticity (FP) is one of the mechanisms by which plants can respond to environmental heterogeneity by adjusting their morphology and physiology. This study tested and quantified the FP of Lippia dulcis plants in response to water availability in soil (low, medium and high), on morphologic and biomass allocation traits during the vegetative ontogeny (days 39, 45, 59 and 66). We hypothesized that in response to water availability, a higher FP should be expected in morphological compared to biomass allocation traits. The leaf mass fraction, leaf area ratio, branch length, number of leaves and root mass/leaf mass ratio, showed the largest capacity of plastic adjustment in the L. dulcis plants to water deficit, whereas the specific leaf area represented the trait with the lowest FP along vegetative ontogeny. The magnitude and pattern of FP changed depending on trait, water availability and ontogenic development. Contrary to our hypothesis the morphological traits and biomass allocation traits showed equivalent FP. The models of optimum allocation and optimum foraging are not mutually exclusive under water deficit. L. dulcis changed its pattern of biomass allocation, leaf and root morphology and as an adaptive advantage optimized the balance between organs involved in water acquisition and use. L. dulcis showed a remarkable ability to avoid water deficit.

  2. Effect of Foliar Application of Chitosan on Growth and Biochemical Characteristics of Safflower (Carthamus tinctorius L. under Water Deficit Stress

    Directory of Open Access Journals (Sweden)

    batool mahdavi

    2014-09-01

    Full Text Available In order to study the effects of water deficit stress and foliar application of chitosan in safflower (Carthamus tinctorius L., a pot experiment was conducted in 2009. Experimental design was a randomized complete block in factorial arrangement with three replications. Experimental factors were water deficit levels (unstressed (control and 70% available water depletion from soil (water deficit stress, chitosan concentrations (0, 0.05, 0.1%, all dissolved in 1% acetic acid along with an additional treatment of distilled water and foliar application times (before and during stem elongation. The results showed that water deficit stress reduced plant height, leaf area, shoot and root dry weight, root height and volume. Whereas, foliar application of chitosan increased mentioned traits. In addition, water deficit stress decreased chlorophyll fluorescence, chlorophyll concentration and relative water content. Carotenoid, proline and malondialdehyde (MDA content were increased in response to stress. Foliar application of chitosan increased chlorophyll fluorescence, relative water content (68.77% and chlorophyll b in the water deficit stressed plants, whereas decreased MDA content. The results of the present study indicate that application of chitosan can reduce the harmful effects of water deficit and improve plant growth.

  3. Fluorescence Indices for the Proximal Sensing of Powdery Mildew, Nitrogen Supply and Water Deficit in Sugar Beet Leaves

    Directory of Open Access Journals (Sweden)

    Georg Leufen

    2014-03-01

    Full Text Available Using potted sugar beet plants we aimed to investigate the suitability of four fluorescence indices to detect and differentiate the impact of nitrogen supply, water deficit and powdery mildew in two sugar beet cultivars (Beta vulgaris L.. Plants were grown inside a polytunnel under two nitrogen levels combined with water deficit or full irrigation. Changes in plant physiology were recorded at two physiological stages with a multiparametric handheld fluorescence sensor and a fluorescence imaging system. The analysis of chlorophyll content and osmotic potential served as reference. Based on our results, the fluorescence indices “Nitrogen Balance Index” and “Simple Fluorescence Ratio” responded quite sensitively to drought stress and mildew infection. Moreover, the blue-to-far-red fluorescence ratio revealed significant stress-induced alterations in the plant physiology. In all, fluorescence indices might be used as single or combined indices for successful stress sensing. However, a robust stress differentiation by using only one fluorescence ratio could not be accomplished.

  4. Anthropogenic Water Uses and River Flow Regime Alterations by Dams

    Science.gov (United States)

    Ferrazzi, M.; Botter, G.

    2017-12-01

    Dams and impoundments have been designed to reconcile the systematic conflict between patterns of anthropogenic water uses and the temporal variability of river flows. Over the past seven decades, population growth and economic development led to a marked increase in the number of these water infrastructures, so that unregulated free-flowing rivers are now rare in developed countries and alterations of the hydrologic cycle at global scale have to be properly considered and characterized. Therefore, improving our understanding of the influence of dams and reservoirs on hydrologic regimes is going to play a key role in water planning and management. In this study, a physically based analytic approach is combined to extensive hydrologic data to investigate natural flow regime alterations downstream of dams in the Central-Eastern United States. These representative case studies span a wide range of different uses, including flood control, water supply and hydropower production. Our analysis reveals that the most evident effects of flood control through dams is a decrease in the intra-seasonal variability of flows, whose extent is controlled by the ratio between the storage capacity for flood control and the average incoming streamflow. Conversely, reservoirs used for water supply lead to an increase of daily streamflow variability and an enhanced inter-catchment heterogeneity. Over the last decades, the supply of fresh water required to sustain human populations has become a major concern at global scale. Accordingly, the number of reservoirs devoted to water supply increased by 50% in the US. This pattern foreshadows a possible shift in the cumulative effect of dams on river flow regimes in terms of inter-catchment homogenization and intra-annual flow variability.

  5. Altered temporal features of intrinsic connectivity networks in boys with combined type of attention deficit hyperactivity disorder

    International Nuclear Information System (INIS)

    Wang, Xun-Heng; Li, Lihua

    2015-01-01

    Highlights: • Temporal patterns within ICNs provide new way to investigate ADHD brains. • ADHD exhibits enhanced temporal activities within and between ICNs. • Network-wise ALFF influences functional connectivity between ICNs. • Univariate patterns within ICNs are correlated to behavior scores. - Abstract: Purpose: Investigating the altered temporal features within and between intrinsic connectivity networks (ICNs) for boys with attention-deficit/hyperactivity disorder (ADHD); and analyzing the relationships between altered temporal features within ICNs and behavior scores. Materials and methods: A cohort of boys with combined type of ADHD and a cohort of age-matched healthy boys were recruited from ADHD-200 Consortium. All resting-state fMRI datasets were preprocessed and normalized into standard brain space. Using general linear regression, 20 ICNs were taken as spatial templates to analyze the time-courses of ICNs for each subject. Amplitude of low frequency fluctuations (ALFFs) were computed as univariate temporal features within ICNs. Pearson correlation coefficients and node strengths were computed as bivariate temporal features between ICNs. Additional correlation analysis was performed between temporal features of ICNs and behavior scores. Results: ADHD exhibited more activated network-wise ALFF than normal controls in attention and default mode-related network. Enhanced functional connectivities between ICNs were found in ADHD. The network-wise ALFF within ICNs might influence the functional connectivity between ICNs. The temporal pattern within posterior default mode network (pDMN) was positively correlated to inattentive scores. The subcortical network, fusiform-related DMN and attention-related networks were negatively correlated to Intelligence Quotient (IQ) scores. Conclusion: The temporal low frequency oscillations of ICNs in boys with ADHD were more activated than normal controls during resting state; the temporal features within ICNs could

  6. Altered temporal features of intrinsic connectivity networks in boys with combined type of attention deficit hyperactivity disorder

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xun-Heng, E-mail: xhwang@hdu.edu.cn [College of Life Information Science and Instrument Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China); School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096 (China); Li, Lihua [College of Life Information Science and Instrument Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China)

    2015-05-15

    Highlights: • Temporal patterns within ICNs provide new way to investigate ADHD brains. • ADHD exhibits enhanced temporal activities within and between ICNs. • Network-wise ALFF influences functional connectivity between ICNs. • Univariate patterns within ICNs are correlated to behavior scores. - Abstract: Purpose: Investigating the altered temporal features within and between intrinsic connectivity networks (ICNs) for boys with attention-deficit/hyperactivity disorder (ADHD); and analyzing the relationships between altered temporal features within ICNs and behavior scores. Materials and methods: A cohort of boys with combined type of ADHD and a cohort of age-matched healthy boys were recruited from ADHD-200 Consortium. All resting-state fMRI datasets were preprocessed and normalized into standard brain space. Using general linear regression, 20 ICNs were taken as spatial templates to analyze the time-courses of ICNs for each subject. Amplitude of low frequency fluctuations (ALFFs) were computed as univariate temporal features within ICNs. Pearson correlation coefficients and node strengths were computed as bivariate temporal features between ICNs. Additional correlation analysis was performed between temporal features of ICNs and behavior scores. Results: ADHD exhibited more activated network-wise ALFF than normal controls in attention and default mode-related network. Enhanced functional connectivities between ICNs were found in ADHD. The network-wise ALFF within ICNs might influence the functional connectivity between ICNs. The temporal pattern within posterior default mode network (pDMN) was positively correlated to inattentive scores. The subcortical network, fusiform-related DMN and attention-related networks were negatively correlated to Intelligence Quotient (IQ) scores. Conclusion: The temporal low frequency oscillations of ICNs in boys with ADHD were more activated than normal controls during resting state; the temporal features within ICNs could

  7. White matter alterations related to attention-deficit hyperactivity disorder and COMT val158met polymorphism: children with valine homozygote attention-deficit hyperactivity disorder have altered white matter connectivity in the right cingulum (cingulate gyrus

    Directory of Open Access Journals (Sweden)

    Kabukcu Basay B

    2016-04-01

    Full Text Available Burge Kabukcu Basay,1 Ahmet Buber,1 Omer Basay,1 Huseyin Alacam,2 Onder Ozturk,1 Serkan Suren,3 Ozlem Izci Ay,4 Cengizhan Acikel,5 Kadir Agladioglu,6 Mehmet Emin Erdal,4 Eyup Sabri Ercan,7 Hasan Herken21Child and Adolescent Psychiatry Department, Pamukkale University Medical Faculty, Denizli, 2Psychiatry Department, Pamukkale University Medical Faculty, Denizli, 3Medical Park Samsun Hospital, Samsun, 4Medical Biology and Genetics Department, Mersin University Medical Faculty, Mersin, 5Biostatistics Department, GATA (GMMA, Ankara, 6Radiology Department, Pamukkale University Medical Faculty, Denizli, 7Child and Adolescent Psychiatry Department, Ege University Medical Faculty, Izmir, TurkeyIntroduction: In this article, the COMT gene val158met polymorphism and attention-deficit hyperactivity disorder (ADHD-related differences in diffusion-tensor-imaging-measured white matter (WM structure in children with ADHD and controls were investigated.Patients and methods: A total of 71 children diagnosed with ADHD and 24 controls aged 8–15 years were recruited. Using diffusion tensor imaging, COMT polymorphism and ADHD-related WM alterations were investigated, and any interaction effect between the COMT polymorphism and ADHD was also examined. The effects of age, sex, and estimated total IQ were controlled by multivariate analysis of covariance (MANCOVA.Results: First, an interaction between the COMT val158met polymorphism and ADHD in the right (R cingulum (cingulate gyrus (CGC was found. According to this, valine (val homozygote ADHD-diagnosed children had significantly lower fractional anisotropy (FA and higher radial diffusivity (RD in the R-CGC than ADHD-diagnosed methionine (met carriers, and val homozygote controls had higher FA and lower RD in the R-CGC than val homozygote ADHD patients. Second, met carriers had higher FA and axial diffusivity in the left (L-uncinate fasciculus and lower RD in the L-posterior corona radiata and L

  8. Molecular, physiological and biochemical responses of Theobroma cacao L. genotypes to soil water deficit.

    Science.gov (United States)

    Santos, Ivanildes C Dos; Almeida, Alex-Alan Furtado de; Anhert, Dário; Conceição, Alessandro S da; Pirovani, Carlos P; Pires, José L; Valle, Raúl René; Baligar, Virupax C

    2014-01-01

    Six months-old seminal plants of 36 cacao genotypes grown under greenhouse conditions were subjected to two soil water regimes (control and drought) to assess, the effects of water deficit on growth, chemical composition and oxidative stress. In the control, soil moisture was maintained near field capacity with leaf water potentials (ΨWL) ranging from -0.1 to -0.5 MPa. In the drought treatment, the soil moisture was reduced gradually by withholding additional water until ΨWL reached values of between -2.0 to -2.5 MPa. The tolerant genotypes PS-1319, MO-20 and MA-15 recorded significant increases in guaiacol peroxidase activity reflecting a more efficient antioxidant metabolism. In relation to drought tolerance, the most important variables in the distinguishing contrasting groups were: total leaf area per plant; leaf, stem and total dry biomass; relative growth rate; plant shoot biomass and leaf content of N, Ca, and Mg. From the results of these analyses, six genotypes were selected with contrasting characteristics for tolerance to soil water deficit [CC-40, C. SUL-4 and SIC-2 (non-tolerant) and MA-15, MO-20, and PA-13 (tolerant)] for further assessment of the expression of genes NCED5, PP2C, psbA and psbO to water deficit. Increased expression of NCED5, PP2C, psbA and psbO genes were found for non-tolerant genotypes, while in the majority of tolerant genotypes there was repression of these genes, with the exception of PA-13 that showed an increased expression of psbA. Mutivariate analysis showed that growth variables, leaf and total dry biomass, relative growth rate as well as Mg content of the leaves were the most important factor in the classification of the genotypes as tolerant, moderately tolerant and sensitive to water deficit. Therefore these variables are reliable plant traits in the selection of plants tolerant to drought.

  9. Endothelial ErbB4 deficit induces alterations in exploratory behavior and brain energy metabolism in mice.

    Science.gov (United States)

    Wu, Gang; Liu, Xiu-Xiu; Lu, Nan-Nan; Liu, Qi-Bing; Tian, Yun; Ye, Wei-Feng; Jiang, Guo-Jun; Tao, Rong-Rong; Han, Feng; Lu, Ying-Mei

    2017-06-01

    The receptor tyrosine kinase ErbB4 is present throughout the primate brain and has a distinct functional profile. In this study, we investigate the potential role of endothelial ErbB4 receptor signaling in the brain. Here, we show that the endothelial cell-specific deletion of ErbB4 induces decreased exploratory behavior in adult mice. However, the water maze task for spatial memory and the memory reconsolidation test reveal no changes; additionally, we observe no impairment in CaMKII phosphorylation in Cdh5Cre;ErbB4 f/f mice, which indicates that the endothelial ErbB4 deficit leads to decreased exploratory activity rather than direct memory deficits. Furthermore, decreased brain metabolism, which was measured using micro-positron emission tomography, is observed in the Cdh5Cre;ErbB4 f/f mice. Consistently, the immunoblot data demonstrate the downregulation of brain Glut1, phospho-ULK1 (Ser555), and TIGAR in the endothelial ErbB4 conditional knockout mice. Collectively, our findings suggest that endothelial ErbB4 plays a critical role in regulating brain function, at least in part, through maintaining normal brain energy homeostasis. Targeting ErbB4 or the modulation of endothelial ErbB4 signaling may represent a rational pharmacological approach to treat neurological disorders. © 2017 John Wiley & Sons Ltd.

  10. Altered cingulo-striatal function underlies reward drive deficits in schizophrenia.

    Science.gov (United States)

    Park, Il Ho; Chun, Ji Won; Park, Hae-Jeong; Koo, Min-Seong; Park, Sunyoung; Kim, Seok-Hyeong; Kim, Jae-Jin

    2015-02-01

    Amotivation in schizophrenia is assumed to involve dysfunctional dopaminergic signaling of reward prediction or anticipation. It is unclear, however, whether the translation of neural representation of reward value to behavioral drive is affected in schizophrenia. In order to examine how abnormal neural processing of response valuation and initiation affects incentive motivation in schizophrenia, we conducted functional MRI using a deterministic reinforcement learning task with variable intervals of contingency reversals in 20 clinically stable patients with schizophrenia and 20 healthy controls. Behaviorally, the advantage of positive over negative reinforcer in reinforcement-related responsiveness was not observed in patients. Patients showed altered response valuation and initiation-related striatal activity and deficient rostro-ventral anterior cingulate cortex activation during reward approach initiation. Among these neural abnormalities, rostro-ventral anterior cingulate cortex activation was correlated with positive reinforcement-related responsiveness in controls and social anhedonia and social amotivation subdomain scores in patients. Our findings indicate that the central role of the anterior cingulate cortex is in translating action value into driving force of action, and underscore the role of the cingulo-striatal network in amotivation in schizophrenia. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. An assessment of crop water deficits of the plants growing on the Małopolska Upland (Poland

    Directory of Open Access Journals (Sweden)

    Kowalczyk Agnieszka

    2016-06-01

    Full Text Available The problem of water scarcity is unfavourable for the economy, with the most significant water deficits felt by agriculture. In Poland water deficits in agriculture are occurring more frequently, causing losses in yield, not only in the Lowland areas but also in the Uplands. This paper presents an assessment of the water deficits at various excedance probability levels for four varieties of field crop and for soil types with various water retention capacity, which occur in the Małopolska Upland. Calculations were performed by balancing the amount of available soil water in the root zone. The study was based on the meteorological data from the Institute of Meteorology and Water Management for the years 1971–2010. Daily precipitation data from six rainfall stations: Borusowa, Igołomia, Książ Wielki, Miechów, Olewin and Sielec was utilised as well as average decadal air temperature, water vapour pressure, wind speed and sunshine hours from the meteorological station at Kraków–Balice. The water deficits at an excedance probability level of 20% fluctuated during the growing season from 5 mm (Phaeozems to 190 mm (Leptosols. In the Małopolska Upland in soils with a medium capacity to retain water (110–160 mm, water deficits have occurred even in years of average rainfall (with probability 50%. This study confirms the considerable impact of the high variability of the soil and pluvial conditions in the region on the water deficits of the field crops.

  12. Moisture Supply From the Western Ghats Forests to Water Deficit East Coast of India

    Science.gov (United States)

    Paul, Supantha; Ghosh, Subimal; Rajendran, K.; Murtugudde, Raghu

    2018-05-01

    The mountainous western coast of India, known as the Western Ghats, is considered to be a biodiversity hot spot, but it is under a constant threat due to human activities. The region is characterized by high orographic monsoon precipitation resulting in dense vegetation cover. Feedback of such a dense vegetation on the southwest monsoon rainfall is not yet explored. Here we perform regional climate simulations with the Weather Research and Forecasting model and find that evapotranspiration from the vegetation of Western Ghats contributes 25-40% of the southwest monsoon rainfall over the water-deficit state of Tamil Nadu. This contribution reaches 50% during deficit monsoon years or dry spells within a season. Our findings suggest that recent deforestation in this area will affect not only the biodiversity of the region but also the water availability over Peninsular India, which is already impacted by water scarcity.

  13. Diurnal variations in water relations of deficit irrigated lemon trees during fruit growth period

    Directory of Open Access Journals (Sweden)

    Y. García-Orellana

    2013-01-01

    Full Text Available Field-grown lemon trees (Citrus limon (L. Burm. fil. cv. Fino were subjected to different drip irrigation treatments: a control treatment, irrigated daily above crop water requirements in order to obtain non-limiting soil water conditions and two deficit irrigation treatments, reducing the water applied according to the maximum daily trunk shrinkage (MDS signal intensity (actual MDS/control treatment MDS threshold values of 1.25 (T1 treatment and 1.35 (T2 treatment, which induced two different drought stress levels. Daily variations in leaf (Yleaf and stem (Ystem water potentials, leaf conductance, net photosynthesis, sap flow (SF and trunk diameter fluctuations were studied on four occasions during the lemon fruit growth period. Ystem and Yleaf revealed a diurnal pattern in response to changes in evaporative demand of the atmosphere. Both water potentials decreased in response to water deficits, which were more pronounced in the T2 treatment. Ystem was seen to be a better plant water status indicator than Yleaf. The difference between the two values of Y (Ystem - Yleaf  = DY was closely correlated with sap flow, making it a suitable measure of leaf transpiration. Using the slope of this relationship, the canopy hydraulic conductance (KC was estimated. When other continuously recorded plant-based indicators are not accessible, the concurrent measurement of leaf and stem water potentials at midday, which are relatively inexpensive to measure and user-friendly, act as sufficiently good indicators of the plant water status in field grown Fino lemon trees.

  14. Agro-physiological and biochemical responses of faba bean (Vicia faba L. var. 'minor' genotypes to water deficit stress

    Directory of Open Access Journals (Sweden)

    Abid, G.

    2017-01-01

    Full Text Available Description of the subject. Drought is one of the major abiotic factors affecting growth and productivity of plants by imposing certain morphological, physiological and biochemical changes at different growth stages. Objectives. The objective of this work is to study key morphological, physiological and biochemical responses of faba bean (Vicia faba L. var. 'minor' to soil water deficit stress and to assess the contribution of genetic factors in improving faba bean tolerance to water deficit. Method. Plants of 11 faba bean cultivars were grown in the greenhouse and subjected to three levels of water deficit (90, 50 and 30% of field capacity [FC] in a simple randomized design for 20 days. Water deficit effects on plant growth, relative water content (RWC, gas exchange, chlorophyll a (Chla and chlorophyll b (Chlb content, osmoprotectant accumulations (such as proline and soluble sugars, antioxidant enzyme activities and grain yield were determined. Results. Soil water deficit stress reduced growth and affected physiological parameters, especially antioxidant enzyme activities. Water deficit also increased proline, soluble sugars and protein contents. The studied cultivars significantly differed in their responses to water deficit stress. Photosynthetic parameters were less affected in the 'Hara' cultivar. Furthermore, this cultivar produced the highest value of grain yield at 30% FC, and showed higher antioxidant enzyme activities (CAT, GPX and APX, osmoprotectant accumulations, Chlb and RWC. The 'Hara' cultivar was found to be more tolerant to water deficit stress than the other cultivars. Conclusions. Our methodology can be used for assessing the response of faba bean genetic resources to soil water deficit. The identified tolerant cultivar can be utilized as a source for water stress tolerance in faba bean breeding programs aimed at improving drought tolerance.

  15. Controlled water deficit during ripening affects proanthocyanidin synthesis, concentration and composition in Cabernet Sauvignon grape skins.

    Science.gov (United States)

    Cáceres-Mella, Alejandro; Talaverano, M Inmaculada; Villalobos-González, Luis; Ribalta-Pizarro, Camila; Pastenes, Claudio

    2017-08-01

    The influence of controlled water deficit on the phenolic composition and gene expression of VvLAR2, VvMYBPA1, VvMYBPA2 and VvMYB4a in Cabernet Sauvignon grape skins throughout ripening was investigated. The assay was carried out on own-rooted Vitis vinifera plants cv. Cabernet Sauvignon in a commercial vineyard from veraison until commercial harvest. Three irrigation regimes were used from veraison until harvest with the following treatments: T1: 3.6 mm day -1 ; T2: 1.8 mm day -1 and T3: 0.3 mm day -1 . The content of total phenols and total anthocyanins in grape skins increased during ripening, but water deficit did not produce differences among treatments in the total anthocyanin concentration. Proanthocyanidins (PAs) decreased throughout ripening, although approximately 25 days after veraison (DAV), their content slightly increased. This effect was more pronounced in the most restrictive treatment (T3). A similar pattern was observed in the transcript abundance of VvLAR2, VvMYBPA1 and VvMYB4a. PAs separation revealed differences in concentration but not in the proportion among fractions among the irrigation treatments. Additionally, controlled water deficit increased the mean degree of polymerization and the flavan-3-ol polymeric concentration in grape skins throughout ripening but with no effects on the extent of PAs galloylation. Our results suggest that the water status of Cabernet Sauvignon grapevines affects the gene expression for proteins involved in the synthesis of PAs, increasing their concentration and also their composition, with further evidence for the efficacy of a convenient, controlled water deficit strategy for grapevine cultivation. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  16. Genome-wide transcriptome analysis of soybean primary root under varying water-deficit conditions.

    Science.gov (United States)

    Song, Li; Prince, Silvas; Valliyodan, Babu; Joshi, Trupti; Maldonado dos Santos, Joao V; Wang, Jiaojiao; Lin, Li; Wan, Jinrong; Wang, Yongqin; Xu, Dong; Nguyen, Henry T

    2016-01-15

    Soybean is a major crop that provides an important source of protein and oil to humans and animals, but its production can be dramatically decreased by the occurrence of drought stress. Soybeans can survive drought stress if there is a robust and deep root system at the early vegetative growth stage. However, little is known about the genome-wide molecular mechanisms contributing to soybean root system architecture. This study was performed to gain knowledge on transcriptome changes and related molecular mechanisms contributing to soybean root development under water limited conditions. The soybean Williams 82 genotype was subjected to very mild stress (VMS), mild stress (MS) and severe stress (SS) conditions, as well as recovery from the severe stress after re-watering (SR). In total, 6,609 genes in the roots showed differential expression patterns in response to different water-deficit stress levels. Genes involved in hormone (Auxin/Ethylene), carbohydrate, and cell wall-related metabolism (XTH/lipid/flavonoids/lignin) pathways were differentially regulated in the soybean root system. Several transcription factors (TFs) regulating root growth and responses under varying water-deficit conditions were identified and the expression patterns of six TFs were found to be common across the stress levels. Further analysis on the whole plant level led to the finding of tissue-specific or water-deficit levels specific regulation of transcription factors. Analysis of the over-represented motif of different gene groups revealed several new cis-elements associated with different levels of water deficit. The expression patterns of 18 genes were confirmed byquantitative reverse transcription polymerase chain reaction method and demonstrated the accuracy and effectiveness of RNA-Seq. The primary root specific transcriptome in soybean can enable a better understanding of the root response to water deficit conditions. The genes detected in root tissues that were associated with

  17. Brassinosteroids improve photosystem II efficiency, gas exchange, antioxidant enzymes and growth of cowpea plants exposed to water deficit.

    Science.gov (United States)

    Lima, J V; Lobato, A K S

    2017-01-01

    Water deficit is considered the main abiotic stress that limits agricultural production worldwide. Brassinosteroids (BRs) are natural substances that play roles in plant tolerance against abiotic stresses, including water deficit. This research aims to determine whether BRs can mitigate the negative effects caused by water deficiency, revealing how BRs act and their possible contribution to increased tolerance of cowpea plants to water deficit. The experiment was a factorial design with the factors completely randomised, with two water conditions (control and water deficit) and three levels of brassinosteroids (0, 50 and 100 nM 24-epibrassinolide; EBR is an active BRs). Plants sprayed with 100 nM EBR under the water deficit presented significant increases in Φ PSII , q P and ETR compared with plants subjected to the water deficit without EBR. With respect to gas exchange, P N , E and g s exhibited significant reductions after water deficit, but application of 100 nM EBR caused increases in these variables of 96, 24 and 33%, respectively, compared to the water deficit + 0 nM EBR treatment. To antioxidant enzymes, EBR resulted in increases in SOD, CAT, APX and POX, indicating that EBR acts on the antioxidant system, reducing cell damage. The water deficit caused significant reductions in Chl a , Chl b and total Chl, while plants sprayed with 100 nM EBR showed significant increases of 26, 58 and 33% in Chl a , Chl b and total Chl, respectively. This study revealed that EBR improves photosystem II efficiency, inducing increases in Φ PSII , q P and ETR. This substance also mitigated the negative effects on gas exchange and growth induced by the water deficit. Increases in SOD, CAT, APX and POX of plants treated with EBR indicate that this steroid clearly increased the tolerance to the water deficit, reducing reactive oxygen species, cell damage, and maintaining the photosynthetic pigments. Additionally, 100 nM EBR resulted in a better dose-response of cowpea

  18. Preliminary evidence of altered neural response during intertemporal choice of losses in adult attention-deficit hyperactivity disorder.

    Science.gov (United States)

    Tanaka, Saori C; Yahata, Noriaki; Todokoro, Ayako; Kawakubo, Yuki; Kano, Yukiko; Nishimura, Yukika; Ishii-Takahashi, Ayaka; Ohtake, Fumio; Kasai, Kiyoto

    2018-04-30

    Impulsive behaviours are common symptoms of attention-deficit hyperactivity disorder (ADHD). Although previous studies have suggested functional models of impulsive behaviour, a full explanation of impulsivity in ADHD remains elusive. To investigate the detailed mechanisms behind impulsive behaviour in ADHD, we applied an economic intertemporal choice task involving gains and losses to adults with ADHD and healthy controls and measured brain activity by functional magnetic resonance imaging. In the intertemporal choice of future gains, we observed no behavioural or neural difference between the two groups. In the intertemporal choice of future losses, adults with ADHD exhibited higher discount rates than the control participants. Furthermore, a comparison of brain activity representing the sensitivity of future loss in the two groups revealed significantly lower activity in the striatum and higher activity in the amygdala in adults with ADHD than in controls. Our preliminary findings suggest that an altered size sensitivity to future loss is involved in apparent impulsive choice behaviour in adults with ADHD and shed light on the multifaceted impulsivity underlying ADHD.

  19. Response of antioxidant system of tomato to water deficit stress and its interaction with ascorbic acid

    Directory of Open Access Journals (Sweden)

    Fatemeh Daneshmand

    2014-03-01

    Full Text Available Environmental stresses including water deficit stress may produce oxidants such as reactive oxygen species that damage the membrane structure in plants. Among the antioxidants, ascorbic acid has a critical role in the cell and scavenges reactive oxygen species. In this research, effects of ascorbic acid at two levels (0 and 10 mM and water deficit stress based on 3 levels of field capacity (100, 60 and 30% were studied in tomato plants. Both levels of stress increased lipid peroxidation, reduced the amount of ascorbic acid and glutathione and increased the activity of enzymes superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase, guaiacol peroxidase and reduced the growth parameters. Ascorbic acid treatment, reduced lipid peroxidation, increased ascorbic acid and glutathione levels and decreased the activity of superoxide dismutase, catalase, ascorbate peroxidase, glutathione peroxidase and guaiacol peroxidase and positive effects of ascorbic acid treatment appeared to improve the plant growth parameters.

  20. Control of expansive growth in water deficit: from phenotyping to field simulations

    OpenAIRE

    Parent , Boris; Cabrera Bosquet , Llorenç; Cané , Maria Angela; Chaumont , François; Alvarez Prado , Santiago; CALDEIRA JuNIOR , Cecilio Frois; Lacube , Sébastien; Fleury , Delphine; Welcker , Claude; Tuberosa , Roberto; Tardieu , Francois

    2015-01-01

    Maintenance of expansive growth under water deficit has been selected as a key target trait of DROPS because of its early response in drying conditions, its large genetic variability, its partially common control with reproductive growth and its consequences on light interception and transpiration. Development of methods to measure shoot growth in Phenotyping platforms (PhenoArch and Phenodyn, M3P, Montpellier, France; The Plant Accelerator, Adelaide, Australia) allowed identification of a...

  1. Alteration mechanisms of UOX spent fuel under water

    International Nuclear Information System (INIS)

    Muzeau, B.

    2008-06-01

    The mechanisms of spent fuel alteration in aqueous media need to be understood on the assumption of a direct disposal of the assemblies in a geological formation or for long duration storage in pool. This work is a contribution to the study of the effects of the alpha and/or beta/gamma radiolysis of water on the oxidation and the dissolution of the UO 2 matrix of UOX spent fuel. The effects of the alpha radiolysis, predominant in geological disposal conditions, were quantified by using samples of UO 2 doped with plutonium. The leaching experiments highlighted two types of control for the matrix alteration according to the alpha activity. The first is based on the radiolytic oxidation of the surface and leads to a continuous release of uranium in solution whereas the second is based on a control by the solubility of uranium. An activity threshold, between 18 MBq.g -1 and 33 MBq.g -1 , was defined in a carbonated water. The value of this threshold is dependent on the experimental conditions and the presence or not of electro-active species such as hydrogen in the system. The effects of the alpha/beta/gamma radiolysis in relation with the storage conditions were also quantified. The experimental data obtained on spent fuel indicate that the alteration rate of the matrix based on the behaviour of tracer elements (caesium and strontium) reached a maximum value of some mg.m -2 .d -1 , even under very oxidizing conditions. The solubility of uranium and the nature of the secondary phases depend however on the extent of the oxidizing conditions. (author)

  2. Exogenous nitric oxide improves sugarcane growth and photosynthesis under water deficit.

    Science.gov (United States)

    Silveira, Neidiquele M; Frungillo, Lucas; Marcos, Fernanda C C; Pelegrino, Milena T; Miranda, Marcela T; Seabra, Amedea B; Salgado, Ione; Machado, Eduardo C; Ribeiro, Rafael V

    2016-07-01

    Nitric oxide (NO)-mediated redox signaling plays a role in alleviating the negative impact of water stress in sugarcane plants by improving root growth and photosynthesis. Drought is an environmental limitation affecting sugarcane growth and yield. The redox-active molecule nitric oxide (NO) is known to modulate plant responses to stressful conditions. NO may react with glutathione (GSH) to form S-nitrosoglutathione (GSNO), which is considered the main reservoir of NO in cells. Here, we investigate the role of NO in alleviating the effects of water deficit on growth and photosynthesis of sugarcane plants. Well-hydrated plants were compared to plants under drought and sprayed with mock (water) or GSNO at concentrations ranging from 10 to 1000 μM. Leaf GSNO sprayed plants showed significant improvement of relative water content and leaf and root dry matter under drought compared to mock-sprayed plants. Additionally, plants sprayed with GSNO (≥ 100 μM) showed higher leaf gas exchange and photochemical activity as compared to mock-sprayed plants under water deficit and after rehydration. Surprisingly, a raise in the total S-nitrosothiols content was observed in leaves sprayed with GSH or GSNO, suggesting a long-term role of NO-mediated responses to water deficit. Experiments with leaf discs fumigated with NO gas also suggested a role of NO in drought tolerance of sugarcane plants. Overall, our data indicate that the NO-mediated redox signaling plays a role in alleviating the negative effects of water stress in sugarcane plants by protecting the photosynthetic apparatus and improving shoot and root growth.

  3. Deficit irrigation of a landscape halophyte for reuse of saline waste water in a desert city

    Science.gov (United States)

    Glenn, E.P.; Mckeon, C.; Gerhart, V.; Nagler, P.L.; Jordan, F.; Artiola, J.

    2009-01-01

    Saline waste waters from industrial and water treatment processes are an under-utilized resource in desert urban environments. Management practices to safely use these water sources are still in development. We used a deeprooted native halophyte, Atriplex lentiformis (quailbush), to absorb mildly saline effluent (1800 mg l-1 total dissolved solids, mainly sodium sulfate) from a water treatment plant in the desert community of Twentynine Palms, California. We developed a deficit irrigation strategy to avoid discharging water past the root zone to the aquifer. The plants were irrigated at about one-third the rate of reference evapotranspiration (ETo) calculated from meteorological data over five years and soil moisture levels were monitored to a soil depth of 4.7 m at monthly intervals with a neutron hydroprobe. The deficit irrigation schedule maintained the soil below field capacity throughout the study. Water was presented on a more or less constant schedule, so that the application rates were less than ETo in summer and equal to or slightly greater than ETo in winter, but the plants were able to consume water stored in the profile in winter to support summer ET. Sodium salts gradually increased in the soil profile over the study but sulfate levels remained low, due to formation of gypsum in the calcic soil. The high salt tolerance, deep roots, and drought tolerance of desert halophytes such as A. lentiformis lend these plants to use as deficit-irrigated landscape plants for disposal of effluents in urban setting when protection of the aquifer is important. ?? 2008 Elsevier B.V.

  4. REUSE OF TREATED WASTEWATER IN AGRICULTURE: SOLVING WATER DEFICIT PROBLEMS IN ARID AREAS (REVIEW

    Directory of Open Access Journals (Sweden)

    Faissal AZIZ

    2014-12-01

    Full Text Available In the arid and semiarid areas, the availability and the management of irrigation water have become priorities of great importance. The successive years of drought, induced by climate change and population growth, increasingly reduced the amount of water reserved for agriculture. Consequently, many countries have included wastewater reuse as an important dimension of water resources planning. In the more arid areas wastewater is used in agriculture, releasing high resource of water supplies. In this context, the present work is a review focusing the reuse of treated wastewater in agriculture as an important strategy for solving water deficit problems in arid areas. Much information concerning the wastewater reuse in different regions of the world and in Morocco, the different wastewater treatment technologies existing in Morocco were discussed. The review focused also the fertilizing potential of wastewater in agriculture, the role of nutrients and their concentrations in wastewater and their advantages effects on plant growth and yield.

  5. Genome-wide identification of differentially expressed genes under water deficit stress in upland cotton (Gossypium hirsutum L.).

    Science.gov (United States)

    Park, Wonkeun; Scheffler, Brian E; Bauer, Philip J; Campbell, B Todd

    2012-06-15

    Cotton is the world's primary fiber crop and is a major agricultural commodity in over 30 countries. Like many other global commodities, sustainable cotton production is challenged by restricted natural resources. In response to the anticipated increase of agricultural water demand, a major research direction involves developing crops that use less water or that use water more efficiently. In this study, our objective was to identify differentially expressed genes in response to water deficit stress in cotton. A global expression analysis using cDNA-Amplified Fragment Length Polymorphism was conducted to compare root and leaf gene expression profiles from a putative drought resistant cotton cultivar grown under water deficit stressed and well watered field conditions. We identified a total of 519 differentially expressed transcript derived fragments. Of these, 147 transcript derived fragment sequences were functionally annotated according to their gene ontology. Nearly 70 percent of transcript derived fragments belonged to four major categories: 1) unclassified, 2) stress/defense, 3) metabolism, and 4) gene regulation. We found heat shock protein-related and reactive oxygen species-related transcript derived fragments to be among the major parts of functional pathways induced by water deficit stress. Also, twelve novel transcripts were identified as both water deficit responsive and cotton specific. A subset of differentially expressed transcript derived fragments was verified using reverse transcription-polymerase chain reaction. Differential expression analysis also identified five pairs of duplicated transcript derived fragments in which four pairs responded differentially between each of their two homologues under water deficit stress. In this study, we detected differentially expressed transcript derived fragments from water deficit stressed root and leaf tissues in tetraploid cotton and provided their gene ontology, functional/biological distribution, and

  6. Diurnal variations in water relations of deficit irrigated lemon trees during fruit growth period

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Orellana, Y.; Ortuno, M. F.; Conejero, W.; Ruiz-Sanchez, M. C.

    2013-05-01

    Field-grown lemon trees (Citrus limon (L.) Burm. fil. cv. Fino) were subjected to different drip irrigation treatments: a control treatment, irrigated daily above crop water requirements in order to obtain non-limiting soil water conditions and two deficit irrigation treatments, reducing the water applied according to the maximum daily trunk shrinkage (MDS) signal intensity (actual MDS/control treatment MDS) threshold values of 1.25 (T1 treatment) and 1.35 (T2 treatment), which induced two different drought stress levels. Daily variations in leaf (Y{sub l}eaf) and stem (Y{sub s}tem) water potentials, leaf conductance, net photosynthesis, sap flow (SF) and trunk diameter fluctuations were studied on four occasions during the lemon fruit growth period. Ystem and Y{sub l}eaf revealed a diurnal pattern in response to changes in evaporative demand of the atmosphere. Both water potentials decreased in response to water deficits, which were more pronounced in the T2 treatment. Y{sub s}tem was seen to be a better plant water status indicator than Y{sub l}eaf. The difference between the two values of Y (Y{sub s}tem - Y{sub l}eaf {Delta}{Psi}) was closely correlated with sap flow, making it a suitable measure of leaf transpiration. Using the slope of this relationship, the canopy hydraulic conductance (KC) was estimated. When other continuously recorded plant-based indicators are not accessible, the concurrent measurement of leaf and stem water potentials at midday, which are relatively inexpensive to measure and user-friendly, act as sufficiently good indicators of the plant water status in field grown Fino lemon trees. (Author) 40 refs.

  7. Identification of Genes Associated with Lemon Floral Transition and Flower Development during Floral Inductive Water Deficits: A Hypothetical Model.

    Science.gov (United States)

    Li, Jin-Xue; Hou, Xiao-Jin; Zhu, Jiao; Zhou, Jing-Jing; Huang, Hua-Bin; Yue, Jian-Qiang; Gao, Jun-Yan; Du, Yu-Xia; Hu, Cheng-Xiao; Hu, Chun-Gen; Zhang, Jin-Zhi

    2017-01-01

    Water deficit is a key factor to induce flowering in many woody plants, but reports on the molecular mechanisms of floral induction and flowering by water deficit are scarce. Here, we analyzed the morphology, cytology, and different hormone levels of lemon buds during floral inductive water deficits. Higher levels of ABA were observed, and the initiation of floral bud differentiation was examined by paraffin sections analysis. A total of 1638 differentially expressed genes (DEGs) were identified by RNA sequencing. DEGs were related to flowering, hormone biosynthesis, or metabolism. The expression of some DEGs was associated with floral induction by real-time PCR analysis. However, some DEGs may not have anything to do with flowering induction/flower development; they may be involved in general stress/drought response. Four genes from the phosphatidylethanolamine-binding protein family were further investigated. Ectopic expression of these genes in Arabidopsis changed the flowering time of transgenic plants. Furthermore, the 5' flanking region of these genes was also isolated and sequence analysis revealed the presence of several putative cis -regulatory elements, including basic elements and hormone regulation elements. The spatial and temporal expression patterns of these promoters were investigated under water deficit treatment. Based on these findings, we propose a model for citrus flowering under water deficit conditions, which will enable us to further understand the molecular mechanism of water deficit-regulated flowering in citrus. Based on gene activity during floral inductive water deficits identified by RNA sequencing and genes associated with lemon floral transition, a model for citrus flowering under water deficit conditions is proposed.

  8. Fluorescence Indices for the Proximal Sensing of Powdery Mildew, Nitrogen Supply and Water Deficit in Sugar Beet Leaves

    OpenAIRE

    Leufen, Georg; Noga, Georg; Hunsche, Mauricio

    2014-01-01

    Using potted sugar beet plants we aimed to investigate the suitability of four fluorescence indices to detect and differentiate the impact of nitrogen supply, water deficit and powdery mildew in two sugar beet cultivars (Beta vulgaris L.). Plants were grown inside a polytunnel under two nitrogen levels combined with water deficit or full irrigation. Changes in plant physiology were recorded at two physiological stages with a multiparametric handheld fluorescence sensor and a fluorescence ima...

  9. Hydrocephalus compacted cortex and hippocampus and altered their output neurons in association with spatial learning and memory deficits in rats.

    Science.gov (United States)

    Chen, Li-Jin; Wang, Yueh-Jan; Chen, Jeng-Rung; Tseng, Guo-Fang

    2017-07-01

    Hydrocephalus is a common neurological disorder in children characterized by abnormal dilation of cerebral ventricles as a result of the impairment of cerebrospinal fluid flow or absorption. Clinical presentation of hydrocephalus varies with chronicity and often shows cognitive dysfunction. Here we used a kaolin-induction method in rats and studied the effects of hydrocephalus on cerebral cortex and hippocampus, the two regions highly related to cognition. Hydrocephalus impaired rats' performance in Morris water maze task. Serial three-dimensional reconstruction from sections of the whole brain freshly froze in situ with skull shows that the volumes of both structures were reduced. Morphologically, pyramidal neurons of the somatosensory cortex and hippocampus appear to be distorted. Intracellular dye injection and subsequent three-dimensional reconstruction and analyses revealed that the dendritic arbors of layer III and V cortical pyramid neurons were reduced. The total dendritic length of CA1, but not CA3, pyramidal neurons was also reduced. Dendritic spine densities on both cortical and hippocampal pyramidal neurons were decreased, consistent with our concomitant findings that the expressions of both synaptophysin and postsynaptic density protein 95 were reduced. These cortical and hippocampal changes suggest reductions of excitatory connectivity, which could underlie the learning and memory deficits in hydrocephalus. © 2016 International Society of Neuropathology.

  10. (-)-P7C3-S243 Protects a Rat Model of Alzheimer's Disease From Neuropsychiatric Deficits and Neurodegeneration Without Altering Amyloid Deposition or Reactive Glia.

    Science.gov (United States)

    Voorhees, Jaymie R; Remy, Matthew T; Cintrón-Pérez, Coral J; El Rassi, Eli; Khan, Michael Z; Dutca, Laura M; Yin, Terry C; McDaniel, Latisha N; Williams, Noelle S; Brat, Daniel J; Pieper, Andrew A

    2017-11-06

    In addition to cognitive deficits, Alzheimer's disease (AD) is associated with other neuropsychiatric symptoms, including severe depression. Indeed, depression often precedes cognitive deficits in patients with AD. Unfortunately, the field has seen only minimal therapeutic advances, underscoring the critical need for new treatments. P7C3 aminopropyl carbazoles promote neuronal survival by enhancing nicotinamide adenine dinucleotide flux in injured neurons. Neuroprotection with P7C3 compounds has been demonstrated in preclinical models of neurodegeneration by virtue of promoting neuronal survival independently of early disease-specific pathology, resulting in protection from cognitive deficits and depressive-like behavior. We hypothesize that P7C3 compounds might be uniquely applicable to patients with AD, given the comorbid presentation of depression and cognitive deficits. Aging male and female wild-type and TgF344-AD rats, a well-characterized preclinical AD model, were administered (-)-P7C3-S243 daily for 9 and 18 months, beginning at 6 months of age. Behavioral phenotypes related to cognition and depression were assessed at 15 and 24 months, and brain pathology and biochemistry were assessed at 24 months. (-)-P7C3-S243 safely protected aging male and female wild-type and TgF344-AD rats from cognitive deficits and depressive-like behavior. Depressive-like behavior occurred earlier than cognitive deficits in TgF344-AD rats, consistent with AD in many patients. Treatment with (-)-P7C3-S243 blocked neurodegeneration in TgF344-AD rats, without altering amyloid deposition or indicators of neuroinflammation. Neuronal cell death-specific treatment approaches, such as P7C3 compounds, may represent a new treatment approach for patients experiencing the combination of cognitive deficits and depression associated with AD. Published by Elsevier Inc.

  11. Correlation between subacute sensorimotor deficits and brain water content after surgical brain injury in rats.

    Science.gov (United States)

    McBride, Devin W; Wang, Yuechun; Sherchan, Prativa; Tang, Jiping; Zhang, John H

    2015-09-01

    Brain edema is a major contributor to poor outcome and reduced quality of life after surgical brain injury (SBI). Although SBI pathophysiology is well-known, the correlation between cerebral edema and neurological deficits has not been thoroughly examined in the rat model of SBI. Thus, the purpose of this study was to determine the correlation between brain edema and deficits in standard sensorimotor neurobehavior tests for rats subjected to SBI. Sixty male Sprague-Dawley rats were subjected to either sham surgery or surgical brain injury via partial frontal lobectomy. All animals were tested for neurological deficits 24 post-SBI and fourteen were also tested 72 h after surgery using seven common behavior tests: modified Garcia neuroscore (Neuroscore), beam walking, corner turn test, forelimb placement test, adhesive removal test, beam balance test, and foot fault test. After assessing the functional outcome, animals were euthanized for brain water content measurement. Surgical brain injury resulted in significantly elevated frontal lobe brain water content 24 and 72 h after surgery compared to that of sham animals. In all behavior tests, significance was observed between sham and SBI animals. However, a correlation between brain water content and functional outcome was observed for all tests except Neuroscore. The selection of behavior tests is critical to determine the effectiveness of therapeutics. Based on this study's results, we recommend using beam walking, the corner turn test, the beam balance test, and the foot fault test since correlations with brain water content were observed at both 24 and 72 h post-SBI. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Correlation between subacute sensorimotor deficits and brain water content after surgical brain injury in rats

    Science.gov (United States)

    McBride, Devin W.; Wang, Yuechun; Sherchan, Prativa; Tang, Jiping; Zhang, John H.

    2015-01-01

    Brain edema is a major contributor to poor outcome and reduced quality of life after surgical brain injury (SBI). Although SBI pathophysiology is well-known, the correlation between cerebral edema and neurological deficits has not been thoroughly examined in the rat model of SBI. Thus, the purpose of this study was to determine the correlation between brain edema and deficits in standard sensorimotor neurobehavior tests for rats subjected to SBI. Sixty male Sprague-Dawley rats were subjected to either sham surgery or surgical brain injury via partial frontal lobectomy. All animals were tested for neurological deficits 24 post-SBI and fourteen were also tested 72 hours after surgery using seven common behavior tests: modified Garcia neuroscore (Neuroscore), beam walking, corner turn test, forelimb placement test, adhesive removal test, beam balance test, and foot fault test. After assessing the functional outcome, animals were euthanized for brain water content measurement. Surgical brain injury resulted in a significantly elevated frontal lobe brain water content 24 and 72 hours after surgery compared to that of sham animals. In all behavior tests, significance was observed between sham and SBI animals. However, a correlation between brain water content and functional outcome was observed for all tests except Neuroscore. The selection of behavior tests is critical to determine the effectiveness of therapeutics. Based on this study’s results, we recommend using beam walking, the corner turn test, the beam balance test, and the foot fault test since correlations with brain water content were observed at both 24 and 72 hours post-SBI. PMID:25975171

  13. Vine water deficit impacts aging bouquet in fine red Bordeaux wine

    Science.gov (United States)

    Picard, Magali; van Leeuwen, Cornelis; Guyon, François; Gaillard, Laetitia; de Revel, Gilles; Marchand, Stéphanie

    2017-08-01

    The aim of this study was to investigate the influence of vine water status on bouquet typicality, revealed after aging, and the perception of three aromatic notes (mint, truffle, and undergrowth) in bottled fine red Bordeaux wines. To address the issue of the role of vine water deficit in the overall quality of fine aged wines, a large set of wines from four Bordeaux appellations were subjected to sensory analysis. As vine water status can be characterized by carbon isotope discrimination (δ13C), this ratio was quantified for each wine studied. Statistical analyses combining δ13C and sensory data highlighted that δ13C values discriminated effectively between the most- and least-typical wines. In addition, Principal Component Analysis revealed correlations between δ13C values and truffle, undergrowth, and mint aromatic notes, three characteristics of the red Bordeaux wine aging bouquet. These correlations were confirmed to be significant using a Spearman statistical test. This study highlighted for the first time that vine water deficit positively relates to the perception of aging bouquet typicality, as well as the expression of its key aromatic nuances.

  14. Photosynthetic and enzymatic metabolism of Schinus terebinthifolius Raddi seedlings under water deficit

    Directory of Open Access Journals (Sweden)

    Danieli Pieretti Nunes

    Full Text Available ABSTRACT Schinus terebinthifolius Raddi is a tree species that can be used in the recovery of degraded areas, as it exhibits rapid growth and has a very expansive root system, facilitating water uptake from the deeper layers of the soil. The objective of this study was to evaluate photosynthesis and enzymatic activity in S. terebinthifolius seedlings under conditions of water deficit and their potential to recover following re-irrigation. The experiment was conducted in a greenhouse under a plastic covering where plants were distributed into two groups: Group 1 - control plants, where irrigation was maintained at 70% of the water retention capacity, and Group 2 - stressed plants, where irrigation was suspended until the photosynthetic rate neared zero, followed by rehydration for 12 days, then a further suspension of irrigation. At the beginning of the experiment and during the suspension of irrigation and rehydration, plants were evaluated for gas and antioxidant enzyme exchanges. Hydric stress significantly reduced photosynthesis, stomatal transpiration conductance, carboxylation efficiency of Rubisco, and the chlorophyll content of the S. terebinthifolius plants. Following rehydration, plants recovered the carboxylation efficiency of Rubisco, but not the photosynthetic rate. Antioxidant enzyme activity increased in both the aerial part and the root in response to water deficit.

  15. Vine Water Deficit Impacts Aging Bouquet in Fine Red Bordeaux Wine

    Directory of Open Access Journals (Sweden)

    Magali Picard

    2017-08-01

    Full Text Available The aim of this study was to investigate the influence of vine water status on bouquet typicality, revealed after aging, and the perception of three aromatic notes (mint, truffle, and undergrowth in bottled fine red Bordeaux wines. To address the issue of the role of vine water deficit in the overall quality of fine aged wines, a large set of wines from four Bordeaux appellations were subjected to sensory analysis. As vine water status can be characterized by carbon isotope discrimination (δ13C, this ratio was quantified for each wine studied. Statistical analyses combining δ13C and sensory data highlighted that δ13C-values discriminated effectively between the most- and least-typical wines. In addition, Principal Component Analysis (PCA revealed correlations between δ13C-values and truffle, undergrowth, and mint aromatic notes, three characteristics of the red Bordeaux wine aging bouquet. These correlations were confirmed to be significant using a Spearman statistical test. This study highlighted for the first time that vine water deficit positively relates to the perception of aging bouquet typicality, as well as the expression of its key aromatic nuances.

  16. The Effect of Water Deficit Imposing Methods on Quantitative and Qualitative Traits of New Potato Cultivar

    Directory of Open Access Journals (Sweden)

    Kh Parvizi

    2016-02-01

    Full Text Available Introduction Water deficiency is the main factor that limits crop production in arid and semiarid regions. Due to limitation in water resources, low efficiency of water in surface irrigation method and irregular rainfall application of sprinkle and triple irrigation methods is inevitable in more regions of Iran. In this respect, it is crucial to employ methods that can improve water use efficiency and do not damage the sustainable production of potato in these regions. Introduction of some potato cultivars that have good capability of yield in deficit irrigation is anopportunity in this case. In previous study new released potato cultivar (Savalan and three other promising clones had more yield and growing potential compared with Agriacultivar. Therefore, it was necessary to evaluate new cultivar (Savalan and promising clones in water deficit irrigation. In this respect, as is expected, if cultivars or clones have more tolerance to water deficit they canbe suitable cultivar candidate and germplasms in water critical water conditions in many regions of Iran. Material and Methods This experiment has been conducted in Agricultural and Natural Resources Research Center of Hamedanin split plot design based on Randomized Complete Block in three replications with two factors, including: 1. Water deficit irrigation treatment, 50, 60, 70, 80, 90 and 100% of regular potato irrigation requirement. 2. Three clones accompanied with Savalan and Sante Cultivars. Irrigation system was tape method. Irrigation treatments were established immediately after cultivation of tubers. Water requirement was calculated through corrected vapotranspiration (ETo determined by Penman-Monteith equation considering 90% water use efficiency. During the growing season, fewgrowing indices including, flowering longevity and harvesting time were recorded along with measurement of dry and fresh root weights. Total yield was measured by selecting randomly of 2 m2in every plot

  17. Partitioning and mobilization of photoassimilate in alfalfa subjected to water deficits

    International Nuclear Information System (INIS)

    Hall, M.H.; Sheaffer, C.C.; Heichel, G.H.

    1988-01-01

    Faster regrowth of a stressed alfalfa (Medicago sativa L.) crop compared to an unstressed crop after rewatering has been reported. The bases of this compensatory response are unknown, but they may be important to understanding adaptation to water stress and to developing crop water management strategies. The authors objectives was to determine the effect of stress induced by water deficit on photoassimilate partitioning and the utilization of stored assimilates during regrowth of alfalfa. Field and greenhouse experiments were conducted using cultivars differing in winterhardiness. Plants were subjected to water stress, pulse-labeled with 14 CO 2 , and sampled following 0, 1, 14, 21, and 28-d translocation periods. Following the 14-d sampling, herbage was harvested and water stress was removed. Cultivars contrasting in winterhardiness responded similarly to water stress. Stressed plant roots contained 73 and 114% more total plant radioactivity (TPR) than the control at the 1 and 14-d translocation periods, respectively. Water stress significantly increased root starch and TPR percentage in the starch fraction, but had much smaller effects on root soluble-sugar concentration and TPR percentage of the root sugar fraction. Herbage regrowth mass following harvest and rewatering of the water-stressed plants was similar to that of the control. Compared to the control, water-stressed alfalfa has greater total nonstructural carbohydrates in the roots, apparently due to increased photoassimilate partitioning to the roots. However, the greater root carbohydrate concentrations did not result in compensatory herbage regrowth following rewatering

  18. Symbiosis with AMF and leaf Pi supply increases water deficit tolerance of woody species from seasonal dry tropical forest.

    Science.gov (United States)

    Frosi, Gabriella; Barros, Vanessa A; Oliveira, Marciel T; Santos, Mariana; Ramos, Diego G; Maia, Leonor C; Santos, Mauro G

    2016-12-01

    In seasonal dry tropical forests, plants are subjected to severe water deficit, and the arbuscular mycorrhizal fungi (AMF) or inorganic phosphorus supply (P i ) can mitigate the effects of water deficit. This study aimed to assess the physiological performance of Poincianella pyramidalis subjected to water deficit in combination with arbuscular mycorrhizal fungi (AMF) and leaf inorganic phosphorus (P i ) supply. The experiment was conducted in a factorial arrangement of 2 water levels (+H 2 O and -H 2 O), 2 AMF levels (+AMF and -AMF) and 2P i levels (+P i and -P i ). Leaf primary metabolism, dry shoot biomass and leaf mineral nutrients were evaluated. Inoculated AMF plants under well-watered and drought conditions had higher photosynthesis and higher shoot biomass. Under drought, AMF, P i or AMF+P i plants showed metabolic improvements in photosynthesis, leaf biochemistry and higher biomass compared to the plants under water deficit without AMF or P i . After rehydration, those plants submitted to drought with AMF, P i or AMF+P i showed a faster recovery of photosynthesis compared to treatment under water deficit without AMF or P i . However, plants under the drought condition with AMF showed a higher net photosynthesis rate. These findings suggest that AMF, P i or AMF+P i increase the drought tolerance in P. pyramidalis, and AMF associations under well-watered conditions increase shoot biomass and, under drought, promoted faster recovery of photosynthesis. Copyright © 2016 Elsevier GmbH. All rights reserved.

  19. Effect of Water Deficit Stress on Peach Growth under Commercial Orchard Management Conditions

    Directory of Open Access Journals (Sweden)

    M. Rahmati

    2015-06-01

    Full Text Available In order to study the sensitivity of vegetative growth to water deficit stress of a late-maturing peach (Prunus persica L. cv. Elberta under orchard conditions, an experiment was conducted as randomized complete-block design with three treatments and four repetitions in Shahdiran commercial orchard in Mashhad during 2011. Three irrigation treatments including 360 (low stress, 180 (moderate stress and 90 (severe stress m3ha-1week-1 using a drip irrigation system (minimum stem water potential near harvest: -1.2, -1.5 and -1.7 MPa, respectively from the mid-pit hardening stage (12th of June until harvest (23rd of Sep. applied. Predawn, stem and leaf water potentials, leaf photosynthesis, transpiration, stomatal conductance and leaf temperature, the number of new shoots on fruit bearing shoots and vegetative shoots lengths during growing season as well as leaf area at harvest were measured. The results showed that water deficit stress had negative effects on peach tree water status, thereby resulting in decreased leaf gas exchange and tree vegetative growth. As significant decreased assimilate production of tree was resulted from both decreased leaf assimilation rate (until about 23 % and 50 %, respectively under moderate and severe stress conditions compared to low stress conditions and decreased leaf area of tree (until about 57% and 79%, respectively under moderate and severe stress conditions compared to low stress conditions at harvest. The significant positive correlation between leaf water potential and vegetative growth of peach revealed that shoot growth would decrease by 30% and 50% of maximum at leaf water potential of –1.56 and –2.30 MPa, respectively.

  20. Peach water relations, gas exchange, growth and shoot mortality under water deficit in semi-arid weather conditions.

    Science.gov (United States)

    Rahmati, Mitra; Davarynejad, Gholam Hossein; Génard, Michel; Bannayan, Mohammad; Azizi, Majid; Vercambre, Gilles

    2015-01-01

    In this study the sensitivity of peach tree (Prunus persica L.) to three water stress levels from mid-pit hardening until harvest was assessed. Seasonal patterns of shoot and fruit growth, gas exchange (leaf photosynthesis, stomatal conductance and transpiration) as well as carbon (C) storage/mobilization were evaluated in relation to plant water status. A simple C balance model was also developed to investigate sink-source relationship in relation to plant water status at the tree level. The C source was estimated through the leaf area dynamics and leaf photosynthesis rate along the season. The C sink was estimated for maintenance respiration and growth of shoots and fruits. Water stress significantly reduced gas exchange, and fruit, and shoot growth, but increased fruit dry matter concentration. Growth was more affected by water deficit than photosynthesis, and shoot growth was more sensitive to water deficit than fruit growth. Reduction of shoot growth was associated with a decrease of shoot elongation, emergence, and high shoot mortality. Water scarcity affected tree C assimilation due to two interacting factors: (i) reduction in leaf photosynthesis (-23% and -50% under moderate (MS) and severe (SS) water stress compared to low (LS) stress during growth season) and (ii) reduction in total leaf area (-57% and -79% under MS and SS compared to LS at harvest). Our field data analysis suggested a Ψstem threshold of -1.5 MPa below which daily net C gain became negative, i.e. C assimilation became lower than C needed for respiration and growth. Negative C balance under MS and SS associated with decline of trunk carbohydrate reserves--may have led to drought-induced vegetative mortality.

  1. Effect of PEG-6000 Imposed Water Deficit on Chlorophyll Metabolism in Maize Leaves

    Directory of Open Access Journals (Sweden)

    Rekha Gadre

    2013-08-01

    Full Text Available Drought stress is one of the major abiotic constraint limiting plant growth and productivity world wide. The current study was undertaken with the aim to investigate the effect of water deficit imposed by PEG-6000, on chlorophyll metabolism in maize leaves to work out the mechanistic details. Leaf segments prepared from primary leaves of etiolated maize seedlings were treated with varying concentrations of polyethylene glycol-6000 (PEG-6000; w/v- 5%, 10%, 20%, 30% in continuous light of intensity 40 Wm-2 at 26±2 °C for 24 h in light chamber. The results demonstrate a concentration dependent decline in chlorophyll content with increasing concentration of polyethylene glycol-6000 (PEG-6000. Reduction in chlorophyll ‘a’ level was to a greater extent than the chlorophyll ‘b’. The RNA content decreased in a concentration dependent manner with PEG, however, proline content increased significantly. Relative water content decreased significantly with the supply of 30% PEG only. A substantial decrease in chlorophyll synthesis due to significant reduction in ALA content and ALAD activity, with no change in chlorophyllase activity with the supply of PEG suggests that water deficit affects chlorophyll formation rather than its degradation.

  2. In vivo phosphoproteome characterization reveals key starch granule-binding phosphoproteins involved in wheat water-deficit response.

    Science.gov (United States)

    Chen, Guan-Xing; Zhen, Shou-Min; Liu, Yan-Lin; Yan, Xing; Zhang, Ming; Yan, Yue-Ming

    2017-10-23

    Drought stress during grain development causes significant yield loss in cereal production. The phosphorylated modification of starch granule-binding proteins (SGBPs) is an important mechanism regulating wheat starch biosynthesis. In this study, we performed the first proteomics and phosphoproteomics analyses of SGBPs in elite Chinese bread wheat (Triticum aestivum L.) cultivar Jingdong 17 under well-watered and water-stress conditions. Water stress treatment caused significant reductions in spike grain numbers and weight, total starch and amylopectin content, and grain yield. Two-dimensional gel electrophoresis revealed that the quantity of SGBPs was reduced significantly by water-deficit treatment. Phosphoproteome characterization of SGBPs under water-deficit treatment demonstrated a reduced level of phosphorylation of main starch synthesis enzymes, particularly for granule-bound starch synthase (GBSS I), starch synthase II-a (SS II-a), and starch synthase III (SS III). Specifically, the Ser34 site of the GBSSI protein, the Tyr358 site of SS II-a, and the Ser837 site of SS III-a exhibited significant less phosphorylation under water-deficit treatment than well-watered treatment. Furthermore, the expression levels of several key genes related with starch biosynthesis detected by qRT-PCR were decreased significantly at 15 days post-anthesis under water-deficit treatment. Immunolocalization showed a clear movement of GBSS I from the periphery to the interior of starch granules during grain development, under both water-deficit and well-watered conditions. Our results demonstrated that the reduction in gene expression or transcription level, protein expression and phosphorylation levels of starch biosynthesis related enzymes under water-deficit conditions is responsible for the significant decrease in total starch content and grain yield.

  3. Regulated deficit irrigation as a water management strategy in Vitis vinifera production

    International Nuclear Information System (INIS)

    Wample, R.L.; Smithyman, R.

    2002-01-01

    An initial six-year study in a commercial vineyard located in the Columbia River Valley of Washington State, United States of America, examined the management practices and potential benefits of regulated deficit irrigation (RDI) on Vitis vinifera cv. Sauvignon blanc. The objective of the treatments was to evaluate the effect of deficit irrigation prior to, compared with after, veraison. Each of four irrigation treatments was applied to 1.6 ha and replicated four times for a total 27.0 ha. Irrigation treatments were based on desired soil moisture levels in the top metre of the profile where most of the root system is found. Soil moisture was monitored using a neutron probe and the information was combined with calculations of evaporative demand to determine the irrigation required on a weekly basis. Vine growth, yield, fruit quality and cold hardiness were monitored throughout the study. The results indicated that RDI prior to veraison was effective in controlling shoot growth, as determined by shoot length and elongation rate, as well as pruning weights. Sixteen wine lots, each of approximately 12,000 litres, were prepared each season. Although there was some effect on berry weight, yield was not always significantly reduced. Full irrigation prior to veraison resulted in excessive shoot growth. RDI applied after veraison to vines with large canopies resulted in greater water deficit stress. Fruit quality was increased by pre-veraison RDI compared to postveraison RDI based on wines made. Regulated deficit irrigation applied at anytime resulted in better early-season lignification of canes and cold hardening of buds. There was a slight improvement in mid-winter cold hardiness of vines subjected to RDI. However, this effect was inconsistent. Studies on Cabernet Sauvignon and White Riesling are underway to confirm these results and to investigate the impact of RDI on fruit quality and winemaking practices. (author)

  4. Primitive Liquid Water of the Solar System in an Aqueous Altered Carbonaceous Chondrite

    Science.gov (United States)

    Tsuchiyama, A.; Miyake, A.; Kitayama, A.; Matsuno, J.; Takeuchi, A.; Uesugi, K.; Suzuki, Y.; Nakano, T.; Zolensky, M. E.

    2016-01-01

    Non-destructive 3D observations of the aqueous altered CM chondrite Sutter's Mill using scanning imaging x-ray microscopy (SIXM) showed that some of calcite and enstatite grains contain two-phase inclusion, which is most probably composed of liquid water and bubbles. This water should be primitive water responsible for aqueous alteration in an asteroid in the early solar system.

  5. Evidence of Altered Brain Responses to Nicotine in an Animal Model of Attention Deficit/Hyperactivity Disorder.

    Science.gov (United States)

    Poirier, Guillaume L; Huang, Wei; Tam, Kelly; DiFranza, Joseph R; King, Jean A

    2017-09-01

    Individuals with attention deficit/hyperactivity disorder (ADHD) are susceptible to earlier and more severe nicotine addiction. To shed light on the relationship between nicotine and ADHD, we examined nicotine's effects on functional brain networks in an animal model of ADHD. Awake magnetic resonance imaging was used to compare functional connectivity in adolescent (post-natal day 44 ± 2) males of the spontaneously hypertensive rat (SHR) strain and two control strains, Wistar-Kyoto and Sprague-Dawley (n = 16 each). We analyzed functional connectivity immediately before and after nicotine exposure (0.4 mg/kg base) in naïve animals, using a region-of-interest approach focussing on 16 regions previously implicated in reward and addiction. Relative to the control groups, the SHR strain demonstrated increased functional connectivity between the ventral tegmental area (VTA) and retrosplenial cortex in response to nicotine, suggesting an aberrant response to nicotine. In contrast, increased VTA-substantia nigra connectivity in response to a saline injection in the SHR was absent following a nicotine injection, suggesting that nicotine normalized function in this circuit. In the SHR, nicotine triggered an atypical response in one VTA circuit while normalizing activity in another. The VTA has been widely implicated in drug reward. Our data suggest that increased susceptibility to nicotine addiction in individuals with ADHD may involve altered responses to nicotine involving VTA circuits. Nicotine addiction is more common among individuals with ADHD. We found that two circuits involving the VTA responded differently to nicotine in animals that model ADHD in comparison to two control strains. In one circuit, nicotine normalized activity that was abnormal in the ADHD animals, while in the other circuit nicotine caused an atypical brain response in the ADHD animals. The VTA has been implicated in drug reward. Our results would be consistent with an interpretation that

  6. Environmental effects on stem water deficit in co-occurring conifers exposed to soil dryness

    Science.gov (United States)

    Oberhuber, Walter; Kofler, Werner; Schuster, Roman; Wieser, Gerhard

    2015-04-01

    We monitored dynamics of stem water deficit (Δ W) and needle water potential ( Ψ) during two consecutive growing seasons (2011 and 2012) in a dry inner Alpine environment (750 m above sea level, Tyrol, Austria), where Pinus sylvestris, Picea abies and Larix decidua form mixed stands. Δ W was extracted from stem circumference variations, which were continuously recorded by electronic band dendrometers (six trees per species) and correlations with environmental variables were performed. Results revealed that (i) Δ W reached highest and lowest values in P. abies and L. decidua, respectively, while mean minimum water potential ( Ψ ea) amounted to -3.0 MPa in L. decidua and -1.8 MPa in P. abies and P. sylvestris. (ii) Δ W and Ψ ea were significantly correlated in P. abies ( r = 0.630; P = 0.038) and L. decidua ( r = 0.646; P = 0.032). (iii) In all species, Δ W reached highest values in late summer and was most closely related to temperature ( P drought-sensitive L. decidua and drought-tolerant P. sylvestris indicate that various water storage locations are depleted in species showing different strategies of water status regulation, i.e. anisohydric vs. isohydric behavior, respectively, and/or water uptake efficiency differs among these species. Close coupling of Δ W to temperature suggests that climate warming affects plant water status through its effect on atmospheric demand for moisture.

  7. Cotton Water Use Efficiency under Two Different Deficit Irrigation Scheduling Methods

    Directory of Open Access Journals (Sweden)

    Jeffrey T. Baker

    2015-08-01

    Full Text Available Declines in Ogallala aquifer levels used for irrigation has prompted research to identify methods for optimizing water use efficiency (WUE of cotton (Gossypium hirsutum L. In this experiment, conducted at Lubbock, TX, USA in 2014, our objective was to test two canopy temperature based stress indices, each at two different irrigation trigger set points: the Stress Time (ST method with irrigation triggers set at 5.5 (ST_5.5 and 8.5 h (ST_8.5 and the Crop Water Stress Index (CWSI method with irrigation triggers set at 0.3 (CWSI_0.3 and 0.6 (CWSI_0.6. When these irrigation triggers were exceeded on a given day, the crop was deficit irrigated with 5 mm of water via subsurface drip tape. Also included in the experimental design were a well-watered (WW control irrigated at 110% of potential evapotranspiration and a dry land (DL treatment that relied on rainfall only. Seasonal crop water use ranged from 353 to 625 mm across these six treatments. As expected, cotton lint yield increased with increasing crop water use but lint yield WUE displayed asignificant (p ≤ 0.05 peak near 3.6 to 3.7 kg ha−1 mm−1 for the ST_5.5 and CWSI_0.3 treatments, respectively. Our results suggest that WUE may be optimized in cotton with less water than that needed for maximum lint yield.

  8. Silicon induced improvement in morpho-physiological traits of maize (zea mays l.) under water deficit

    International Nuclear Information System (INIS)

    Amin, M.; Ahmad, R.; Basra, S.M.A.; Murtaza, G.

    2014-01-01

    Current water scarcity is an emerging issue in semi-arid regions like Pakistan and cause of deterioration in productivity of crops to reduce crop yield all over the world. Silicon is known to be better against the deleterious effects of drought on plant growth and development. A pot study was conducted to evaluate the effect of Si nutrition (0, 50, 100 and 150 mg/kg) on the growth of a relatively drought tolerant (P-33H25) and sensitive (FH-810) maize hybrids. Two levels of soil water content were used viz. 100 and 60% of field capacity. Water deficit condition in soil significantly reduced morphological and physiological attributes of maize plants. Silicon application significantly improved the plant height, leaf area per plant, primary root length, dry matter of shoot and roots and plant dry matter, water relation and gas exchange characteristics of both maize cultivars under water deficit condition. Poor growth of drought stressed plants was significantly improved with Si application. The silicon fertilized (100 mg/kg) drought stressed plants of hybrid P-33H25 produced maximum (21.68% more) plant dry matter as compared to plants that were not provided with silicon nutrition. Nonetheless, silicon application (150 mg/kg) resulted in maximum increase (26.03%) in plant dry weight of hybrid FH-810 plants that were grown under limited moisture supply i.e., 60% FC. In conclusion silicon application to drought stressed maize plants was better to improve the growth and dry matter could be attributed to improved osmotic adjustment, photosynthetic rate and lowered transpiration. (author)

  9. WATER DEFICIT EFFECT ON YIELD AND FORAGE QUALITY OF MEDICAGO SATIVA POPULATIONS UNDER FIELD CONDITIONS IN MARRAKESH AREA (MOROCCO

    Directory of Open Access Journals (Sweden)

    Mohamed FARISSI

    2014-06-01

    Full Text Available The present study focused the effect of water deficit on agronomic potential and some traits related to forage quality in plants of Moroccan Alfalfa (Medicago sativa L. populations (Taf 1, Taf 2, Dem and Tata originated from Oasis and High Atlas of Morocco and an introduced variety from Australia (Siriver. The experiment was conducted under field conditions in experimental station of INRA-Marrakech and under two irrigation treatments. The first treatment was normal irrigation, providing an amount of water corresponding to the potential evapo-transpiration of the crop, and the second treatment was water deficit stress (one irrigation per cut. For each treatment, the experiment was conducted as a split plot based on a randomized complete block design with four replications. The plants were measured and analyzed over three cuts. Some agronomic traits as, plant height, fresh and dry forage yields were measured. The forage quality was evaluated by leaf:stem ratio and the contents of plants in proteins and nitrogen. The results indicated that the water deficit has negatively affected the plant height and forage yield. The decrease in leaf:stem ratio was observed under water deficit conditions. However, the proteins and nitrogen contents were unaffected. The behavior of tested alfalfa genotypes was significantly different. The Moroccan alfalfa populations were more adapted to water deficit conditions comparatively to Siriver variety and the Tata population was the most adapted one.

  10. Effect of nitrogen and water deficit type on the yield gap between the potential and attainable wheat yield

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    Jiangang Liu

    2015-12-01

    Full Text Available Water deficit and N fertilizer are the two primary limiting factors for wheat yield in the North China plain, the most important winter wheat (Triticum aestivum L. production area in China. Analyzing the yield gap between the potential yield and the attainable yield can quantify the potential for increasing wheat production and exploring the limiting factors to yield gap in the high-yielding farming region of North China Plain. The Decision Support System for Agrotechnology Transfer (DSSAT model was used to identify methods to increase the grain yield and decrease the gap. In order to explore the impact of N and cultivars on wheat yield in the different drought types, the climate conditions during 1981 to 2011 growing seasons was categorized into low, moderate, and severe water deficit classes according to the anomaly percentage of the water deficit rate during the entire wheat growing season. There are differences (P < 0.0001 in the variations of the potential yields among three cultivars over 30 yr. For all three water deficit types, the more recent cultivars Jimai22 and Shijiazhuang8 had higher yields compared to the older 'Jinan17'. As the N fertilizer rate increased, the yield gap decreased more substantially during the low water deficit years because of the significant increase in attainable yield. Overall, the yield gaps were smaller with less water stress. Replacement of cultivars and appropriate N fertilizer application based on the forecasted drought types can narrow the yield gap effectively.

  11. Estimating Runoff and Soil Moisture Deficit in Guinea Savannah Region of Nigeria using Water Balance Method

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    A. R. Adesiji

    2012-12-01

    Full Text Available The estimation of runoff and soil moisture deficit in Guinea Savannah region using semi arid model based on soil water balance technique (SAMBA was carried out. The input to the SAMBA model are daily rainfall, daily evapotranspiration, type and date of planting of crop, and soil parameters. The estimated runoff was validated with field measurement taken in a 67.23 ha catchment in the study area. The annual rainfall for the year under study (2009 is 1356.2 mm, the estimated annual evapotranspiration. runoff and recharge are 638mm, 132.93mm, and 447.8mm respectively. Recharge was experienced 23 days after a significant depth of rainfall was recorded. For the crop growth in the catchment, the soil was cropped with a pepper and the growth monitored from the planting to the harvesting. The crop enjoyed so much moisture throughout the growing period as Total Available Water in the soil is greater than Soil Moisture Deficit (TAW>SMD. The model results show that the larger percentage of the total annual rainfall was lost to evaporation and recharge during the growing season. The low runoff and high recharge are attributed to soil characteristics of the area and moderate terrain of the study area.

  12. Identification of water-deficit responsive genes in maritime pine (Pinus pinaster Ait.) roots.

    Science.gov (United States)

    Dubos, Christian; Plomion, Christophe

    2003-01-01

    Root adaptation to soil environmental factors is very important to maritime pine, the main conifer species used for reforestation in France. The range of climates in the sites where this species is established varies from flooded in winter to drought-prone in summer. No studies have yet focused on the morphological, physiological or molecular variability of the root system to adapt its growth to such an environment. We developed a strategy to isolate drought-responsive genes in the root tissue in order to identify the molecular mechanisms that trees have evolved to cope with drought (the main problem affecting wood productivity), and to exploit this information to improve drought stress tolerance. In order to provide easy access to the root system, seedlings were raised in hydroponic solution. Polyethylene glycol was used as an osmoticum to induce water deficit. Using the cDNA-AFLP technique, we screened more than 2500 transcript derived fragments, of which 33 (1.2%) showed clear variation in presence/absence between non stressed and stressed medium. The relative abundance of these transcripts was then analysed by reverse northern. Only two out of these 33 genes showed significant opposite behaviour between both techniques. The identification and characterization of water-deficit responsive genes in roots provide the emergence of physiological understanding of the patterns of gene expression and regulation involved in the drought stress response of maritime pine.

  13. Partitioning and mobilization of photoassimilate by alfalfa subjected to water deficits

    International Nuclear Information System (INIS)

    Hall, M.H.

    1987-01-01

    Our objective was to determine the effect of stress induced by water deficit on photoassimilate partitioning and the utilization of stored assimilates during regrowth. Field and greenhouse experiments were conducted using alfalfa cultivars differing in winter hardiness. Plants were subjected to water stress, pulse-labeled with 14 CO 2 , and sampled following 0, 1, and 14 d translocation periods. Subsequent samples were taken at 7 and 14 d after harvest and rewatering. Water stress resulted in herbage and root dry mass of 65 and 119% of the control, respectively, 14 d after labeling. Stressed plants had similar net carbon exchange and respiration rates but retained 10% greater percent total plant radioactivity (%TPR) in the leaves at the onset of the translocation period than did those of the control. Roots of water-stressed plants had 8% more starch and 12% greater %TPR in the starch fraction 14 d after labeling than did roots of control plants. The stressed plant roots contained 73 and 114% more %TPR than the control at the 1 and 14 d translocation periods, respectively. Water stress had no effect on individual or total root sugar concentration or the %TPR of the root sugar fraction. Alfalfa regrowth mass following harvest and rewatering of the water-stressed plants were similar to that of the control

  14. Development of lucerne (Medicago sativa L.) treated with mineral fertilizer and manure at optimal and water deficit conditions.

    Science.gov (United States)

    Vasileva, V; Kostov, O; Vasilev, E

    2006-01-01

    A study on the effect of different rates of mineral fertilizer and manure on yield parameters of lucerne under optimal and water deficit conditions was carried out. Leached chernozem soil and lucerne cultivar Victoria were used. The soil was treated with ammonium nitrate and fully matured cattle manure. The plants were grown under optimum moisture content of 80% and 40% of field capacity. The water deficit stress decreased top and root biomass by 11-75% and 3-29% at mineral and organic fertilization, respectively. The applied mineral and organic N strongly depressed nodules development. Both mineral fertilizer and organic manure at dose of 210 mg N kg(-1) soil completely inhibited the appearance of nodules. Next to nitrogen, water deficit stress further inhibited the development of nodules. Nitrogen fertilization increased seed productivity in the two experimental moisture conditions. The water deficit stress decreased seed productivity by 18 to 33% as compared to optimum conditions. The plant treatments with manure were much more resistant to water deficit and recovering ability of plants was faster as compared to treatments with mineral fertilizer. The application of manure stimulates development of drought-stress tolerance in lucerne. However, the results obtained can be considered for the soil type and experimental conditions used.

  15. Survey the Effects of Partial Root Zone Deficit Irrigation and Deficit Irrigation on Quantitative, Qualitative and Water Use Efficiency of Pomegranate

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    mohammad saeed tadaion

    2017-12-01

    Full Text Available Introduction: One of the latest efficient methods on increment of water use efficiency that confirmed by many scientists all over the world is deficit and alternative partial root zone deficit irrigation. In this experiment the effect of deficit and alternative partial root zone deficit irrigation on fruit yield, quality and water use efficiency of pomegranate (Punicagranatum (L. cv. Zarde-anar were investigatedin Arsenjan semi-arid region. Materials and Methods: The experiment was carried out in a constant plots and randomized complete block design (RCBD with four replicationsin five years.Treatmentswere 1- full flood irrigation (100 percent crop water requirement (T1 2- flood irrigation with 100 percent crop water requirement as alternate partial root-zone irrigation(every irrigation conducted on one side of tree (T2 3- flood irrigation with 50 percent crop water requirement as regular deficit irrigation (T3 4- full two-side drip irrigation(with regard to crop water requirement (eight drippers with twolit/hour flow by two different individual networks (T4 5- alternate partial root-zone drip irrigation with 100 percent crop water requirement (T5 6- regular deficit drip irrigation with 50 percent crop water requirement (T6 in every irrigation period. Each experimental treatment includes four trees and 96 similar twelve years old trees overall. Cultivation practice was conducted similarly on all of the trees. Results and Discussion: Results showed that the highest yield and water use efficiency based on statistical analysis belong to both PRD treatments i.e. alternate partial root-zone drip irrigation with 100 percent crop water requirement and alternate partial root-zone flood irrigation with 100 percent crop water requirement, respectively, that both of them decreased water requirement for irrigation up to 35 and 50 percent in comparison tocontrol. Application of partial root drying irrigation on both traditional flood irrigation and drip

  16. PHYSIOLOGICAL RESPONSES OF DWARF COCONUT PLANTS UNDER WATER DEFICIT IN SALT - AFFECTED SOILS

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    ALEXANDRE REUBER ALMEIDA DA SILVA

    2017-01-01

    Full Text Available The objective of this study was to characterize the physiological acclimation responses of young plants of the dwarf coconut cultivar ̳Jiqui Green‘ associated with tolerance to conditions of multiple abiotic stresses (drought and soil salinity, acting either independently or in combination. The study was conducted under controlled conditions and evaluated the following parameters: leaf gas exchange, quantum yield of chlorophyll a fluorescence, and relative contents of total chlorophyll (SPAD index. The experiment was conducted under a randomized block experimental design, in a split plot arrangement. In the plots, plants were exposed to different levels of water stress, by imposing potential crop evapotranspiration replacement levels equivalent to 100%, 80%, 60%, 40%, and 20%, whereas in subplots, plants were exposed to different levels of soil salinity (1.72, 6.25, 25.80, and 40.70 dS m - 1 . Physiological mechanisms were effectively limited when water deficit and salinity acted separately and/or together. Compared with soil salinity, water stress was more effective in reducing the measured physiological parameters. The magnitudes of the responses of plants to water supply and salinity depended on the intensity of stress and evaluation period. The physiological acclimation responses of plants were mainly related to stomatal regulation. The coconut tree has a number of physiological adjustment mechanisms that give the species partial tolerance to drought stress and/or salt, thereby enabling it to revegetate salinated areas, provided that its water requirements are at least partially met.

  17. Water Relations, Gas Exchange, and Nutrient Response to a Long Term Constant Water Deficit

    Science.gov (United States)

    Berry, Wade L.; Goldstein, Guillermo; Dreschel, Thomas W.; Wheeler, Raymond M.; Sager, John C.; Knott, William M.

    1992-01-01

    Wheat plants (Triticum aestivum) were grown for 43 days in a micro-porous tube nutrient delivery system. Roots were unable to penetrate the microporous tube, but grew on the surface and maintained capillary contact with the nutrient solution on the inside of the tube through the 5-micron pores of the porous tube. Water potential in the system was controlled at -0.4, -0.8, and -3.0 kPa by adjusting the applied pressure (hydrostatic head) to the nutrient solution flowing through the microporous tubes. A relatively small decrease in applied water potential from -0.4 to -3.0 kPa resulted in a 34% reduction of shoot growth but only a moderate reduction in the midday leaf water potential from -1.3 to -1.7 MPa. Carbon dioxide assimilation decreased and water use efficiency increased with the more negative applied water potentials, while intercellular CO2 concentration remained constant. This was associated with a decrease in stomatal conductance to water vapor from 1.90 to 0.98 mol/(sq m sec) and a decrease in total apparent hydraulic conductance from 47 to 12 (micro)mol/(sec MPa). Although the applied water potentials were in the -0.4 to -3.0 kPa range, the actual water potential perceived by the plant roots appeared to be in the range of -0.26 to -0.38 MPa as estimated by the leaf water potential of bagged plants. The amount of K, Ca, Mg, Zn, Cu, and B accumulated with each unit of transpired water increased as the applied water potential became less negative. The increase in accumulation ranged from 1.4-fold for K to 2.2-fold for B. The physiological responses observed in this study in response to small constant differences in applied water potentials were much greater than expected from either the applied water potential or the observed plant water potential. Even though the micro-porous tube may not represent natural conditions and could possibly introduce morphological and physiological artifacts, it enables a high degree of control of water potential that

  18. Water deficit effects on maize yields modeled under current and greenhouse climates

    International Nuclear Information System (INIS)

    Muchow, R.C.; Sinclair, T.R.

    1991-01-01

    The availability of water imposes one of the major limits on rainfed maize (Zea mays L.) productivity. This analysis was undertaken in an attempt to quantify the effects of limited water on maize growth and yield by extending a simple, mechanistic model in which temperature regulates crop development and intercepted solar radiation is used to calculate crop biomass accumulation. A soil water budget was incorporated into the model by accounting for inputs from rainfall and irrigation, and water use by soil evaporation and crop transpiration. The response functions of leaf area development and crop gas exchange to the soil water budget were developed from experimental studies. The model was used to interpret a range of field experiments using observed daily values of temperature, solar radiation, and rainfall or irrigation, where water deficits of varying durations developed at different stages of growth. The relative simplicity of the model and its robustness in simulating maize yields under a range of water-availability conditions allows the model to be readily used for studies of crop performance under alternate conditions. One such study, presented here, was a yield assessment for rainfed maize under possible greenhouse climates where temperature and atmospheric CO 2 concentration were increased. An increase in temperature combined with decreased rainfall lowered grain yield, although the increase in crop water use efficiency associated with elevated CO 2 concentration ameliorated the response to the greenhouse climate. Grain yields for the greenhouse climates as compared to current conditions increased, or decreased only slightly, except when the greenhouse climate was assumed to result in severly decreased rainfall

  19. Using deficit irrigation with treated wastewater to improve crop water productivity of sweet corn, chickpea, faba bean and quinoa

    Directory of Open Access Journals (Sweden)

    Abdelaziz HIRICH

    2014-07-01

    Full Text Available Several experiments were conducted in the south of Morocco (IAV-CHA, Agadir during two seasons 2010 and 2011 in order to evaluate the effect of deficit irrigation with treated wastewater on several crops (quinoa, sweet corn, faba bean and chickpeas. During the first season (2010 three crops were tested, quinoa, chickpeas and sweet corn applying 6 deficit irrigation treatments during all crop stages alternating 100% of full irrigation as non-stress condition and 50% of full irrigation as water deficit condition applied during vegetative growth, flowering and grain filling stage. For all crops, the highest water productivity and yield were obtained when deficit irrigation was applied during the vegetative growth stage. During the second season (2011 two cultivars of quinoa, faba bean and sweet corn have been cultivated applying 6 deficit irrigation treatments (rainfed, 0, 25, 50, 75 and 100% of full irrigation only during the vegetative growth stage, while in the rest of crop cycle full irrigation was provided except for rainfed treatment. For quinoa and faba bean, treatment receiving 50% of full irrigation during vegetative growth stage recorded the highest yield and water productivity, while for sweet corn applying 75% of full irrigation was the optimal treatment in terms of yield and water productivity.

  20. Smoking and the Developing Brain : Altered White Matter Microstructure in Attention-Deficit/Hyperactivity Disorder and Healthy Controls

    NARCIS (Netherlands)

    van Ewijk, Hanneke; Groenman, Annabeth P.; Zwiers, Marcel P.; Heslenfeld, Dirk J.; Faraone, Stephen V.; Hartman, Catharina A.; Luman, Marjolein; Greven, Corina U.; Hoekstra, Pieter J.; Franke, Barbara; Buitelaar, Jan; Oosterlaan, Jaap

    Brain white matter (WM) tracts, playing a vital role in the communication between brain regions, undergo important maturational changes during adolescence and young adulthood, a critical period for the development of nicotine dependence. Attention-deficit/hyperactivity disorder (ADHD) is associated

  1. Life-history responses of insects to water-deficit stress: a case study with the aphid Sitobion avenae.

    Science.gov (United States)

    Liu, Deguang; Dai, Peng; Li, Shirong; Ahmed, Syed Suhail; Shang, Zheming; Shi, Xiaoqin

    2018-05-29

    Drought may become one of the greatest challenges for cereal production under future warming scenarios, and its impact on insect pest outbreaks is still controversial. To address this issue, life-history responses of the English grain aphid, Sitobion avenae (Fabricius), from three areas of different drought levels were compared under three water treatments. Significant differences were identified in developmental time, fecundity and adult weight among S. avenae clones from moist, semiarid and arid areas under all the three water treatments. Semiarid and arid area clones tended to have higher heritability for test life-history traits than moist area clones. We identified significant selection of water-deficit on the developmental time of 1st instar nymphs and adult weight for both semiarid and arid area clones. The impact of intermediate and severe water-stress on S. avenae's fitness was neutral and negative (e.g., decreased fecundity and weight), respectively. Compared with arid-area clones, moist- and semiarid-area clones showed higher extents of adaptation to the water-deficit level of their respective source environment. Adult weight was identified as a good indicator for S. avenae's adaptation potential under different water-stress conditions. After their exposure to intermediate water-deficit stress for only five generations, adult weight and fecundity tended to decrease for moist- and semiarid-area clones, but increase for arid-area clones. It is evident from our study that S. avenae clones from moist, semiarid and arid areas have diverged under different water-deficit stress, and such divergence could have a genetic basis. The impact of drought on S. avenae's fitness showed a water-level dependent pattern. Clones of S. avenae were more likely to become adapted to intermediate water-deficit stress than severe water-deficit stress. After continuous water-deficit stress of only five generations, the adaptation potential of S. avenae tended to decrease for moist

  2. The functional dependence of canopy conductance on water vapor pressure deficit revisited

    Science.gov (United States)

    Fuchs, Marcel; Stanghellini, Cecilia

    2018-03-01

    Current research seeking to relate between ambient water vapor deficit (D) and foliage conductance (g F ) derives a canopy conductance (g W ) from measured transpiration by inverting the coupled transpiration model to yield g W = m - n ln(D) where m and n are fitting parameters. In contrast, this paper demonstrates that the relation between coupled g W and D is g W = AP/D + B, where P is the barometric pressure, A is the radiative term, and B is the convective term coefficient of the Penman-Monteith equation. A and B are functions of g F and of meteorological parameters but are mathematically independent of D. Keeping A and B constant implies constancy of g F . With these premises, the derived g W is a hyperbolic function of D resembling the logarithmic expression, in contradiction with the pre-set constancy of g F . Calculations with random inputs that ensure independence between g F and D reproduce published experimental scatter plots that display a dependence between g W and D in contradiction with the premises. For this reason, the dependence of g W on D is a computational artifact unrelated to any real effect of ambient humidity on stomatal aperture and closure. Data collected in a maize field confirm the inadequacy of the logarithmic function to quantify the relation between canopy conductance and vapor pressure deficit.

  3. DEFICIT IRRIGATION TECHNIQUE FOR REDUCING WATER USE OF TOMATO UNDER POLYTUNNEL CONDITIONS

    Directory of Open Access Journals (Sweden)

    Sladjana SAVIC

    2012-01-01

    Full Text Available The aim of paper was to asses the use of regulated deficit irrigation (RDI for production of two tomato cultivars (Cedrico and Abellus in polytunnels in Serbia. RDI plants received 60% of the water that was applied to FI plants and significant saving of water for irrigation and increased in irrigation water use efficiency (IWUE were achieved. Yield data for Cedrico cultivar showed no differences between RDI and FI, while due to the bigger sensitivity to drought, yield of Abellus was reduced under RDI. In general, fruit quality (soluble solids, titrable acidity was sustained or improved in both cultivars under RDI. Economic analyses showed that due to the current low prices of water and electricity in Serbia, the profit increase of Cedrico, similarly to the previously trialed cultivar Amati, was not high under RDI comparing to FI. Reduction of yield and consequent profit for Abellus, indicated that for future commercial growing of tomato under RDI should be used drought resistant cultivars.

  4. Grapevine acclimation to water deficit: the adjustment of stomatal and hydraulic conductance differs from petiole embolism vulnerability.

    Science.gov (United States)

    Hochberg, Uri; Bonel, Andrea Giulia; David-Schwartz, Rakefet; Degu, Asfaw; Fait, Aaron; Cochard, Hervé; Peterlunger, Enrico; Herrera, Jose Carlos

    2017-06-01

    Drought-acclimated vines maintained higher gas exchange compared to irrigated controls under water deficit; this effect is associated with modified leaf turgor but not with improved petiole vulnerability to cavitation. A key feature for the prosperity of plants under changing environments is the plasticity of their hydraulic system. In the present research we studied the hydraulic regulation in grapevines (Vitis vinifera L.) that were first acclimated for 39 days to well-watered (WW), sustained water deficit (SD), or transient-cycles of dehydration-rehydration-water deficit (TD) conditions, and then subjected to varying degrees of drought. Vine development under SD led to the smallest leaves and petioles, but the TD vines had the smallest mean xylem vessel and calculated specific conductivity (k ts ). Unexpectedly, both the water deficit acclimation treatments resulted in vines more vulnerable to cavitation in comparison to WW, possibly as a result of developmental differences or cavitation fatigue. When exposed to drought, the SD vines maintained the highest stomatal (g s ) and leaf conductance (k leaf ) under low stem water potential (Ψ s ), despite their high xylem vulnerability and in agreement with their lower turgor loss point (Ψ TLP ). These findings suggest that the down-regulation of k leaf and g s is not associated with embolism, and the ability of drought-acclimated vines to maintain hydraulic conductance and gas exchange under stressed conditions is more likely associated with the leaf turgor and membrane permeability.

  5. MzPIP2;1: An Aquaporin Involved in Radial Water Movement in Both Water Uptake and Transportation, Altered the Drought and Salt Tolerance of Transgenic Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Lin Wang

    Full Text Available Plants are unavoidably subjected to various abiotic stressors, including high salinity, drought and low temperature, which results in water deficit and even death. Water uptake and transportation play a critical role in response to these stresses. Many aquaporin proteins, localized at different tissues, function in various transmembrane water movements. We targeted at the key aquaporin in charge of both water uptake in roots and radial water transportation from vascular tissues through the whole plant.The MzPIP2;1 gene encoding a plasma membrane intrinsic protein was cloned from salt-tolerant apple rootstock Malus zumi Mats. The GUS gene was driven by MzPIP2;1 promoter in transgenic Arabidopsis. It indicated that MzPIP2;1 might function in the epidermal and vascular cells of roots, parenchyma cells around vessels through the stems and vascular tissues of leaves. The ectopically expressed MzPIP2;1 conferred the transgenic Arabidopsis plants enhanced tolerance to slight salt and drought stresses, but sensitive to moderate salt stress, which was indicated by root length, lateral root number, fresh weight and K+/Na+ ratio. In addition, the possible key cis-elements in response to salt, drought and cold stresses were isolated by the promoter deletion experiment.The MzPIP2;1 protein, as a PIP2 aquaporins subgroup member, involved in radial water movement, controls water absorption and usage efficiency and alters transgenic plants drought and salt tolerance.

  6. Differential Antioxidative Responses to Water Deficit Among four Barley (Hordeum vulgare L. Genotypes

    Directory of Open Access Journals (Sweden)

    Z Amini

    2013-08-01

    Full Text Available Future climate changes are expected to increase risks of drought, which already represent the most common stress factor for stable barley (Hordeum vulgare L. production in Iran. Up to now, extensive research projects have been done to study effects of drought stress on the antioxidant enzyme activity. While there is a few works of such studies on the field condition. In order to study of water deficit effects on the antioxidant enzymes activities as a secondary stress, we evaluate the effects of mild and severe drought stress on activities of antioxidative enzymes including superoxide dismutases, ascorbate peroxidase, catalase and peroxidase, among four barley genotypes, differing in the capacity to maintain the grain yield under drought condition during beginning on anthesis, kernel watery ripe and late milk stages under field condition. Results showed that drought increased the activity of antioxidant enzymes in all genotypes. At beginning of anthesis, POX activity of Q22 was higher than it in other genotypes ( P

  7. Foliar nitrogen and potassium applications improve photosynthetic activities and water relations in sunflower under moisture deficit condition

    International Nuclear Information System (INIS)

    Hussain, R.A.; Ahmad, R.

    2016-01-01

    This study investigated the influence of foliar supplementation of nitrogen (N) potassium (K) and their combination on photosynthetic activities, physiological indices and water relations of two sunflower (Helianthus annuus L.) hybrids Hysen-33 and LG-5551 under water deficit condition. Studies were conducted in a wire-house at Nuclear Institute for Agriculture and Biology, Faisalabad, Pakistan. Treatments were two water stress levels [100 (control) and 60% field capacity (water deficit)], six levels of foliar spray (no spray, water spray, 1% N, 1% K, 0.5% N + 0.5% K and 1% N + 1% K) and each treatment was replicated three times. Results showed that water stress reduced the photosynthetic activities: Pn (photosynthetic rate), E (rate of tanspiration) and gs (stomatal conductance) and water relations i.e., pie w (water potential), pie s (osmotic potential) and pie p (turgor potential) . Soil moisture deficit also significantly reduced the plant height, root length, fresh and dry matter which consequently affected the plant height stress tolerance index (PHSI), root length stress tolerance index (RLSI) and dry matter stress tolerance index (DMSI) in both sunflower hybrids. However, foliar supplementation with N and K or N+K improved the photosynthetic activities, water relations and physiological indices of both the sunflower hybrids. The findings of present study suggest that application of N+K is necessary to have high plant productivity. (author)

  8. Carbon-13 discrimination as a criterion for identifying high water use efficiency wheat cultivars under water deficit conditions

    International Nuclear Information System (INIS)

    Bazza, M.

    1996-01-01

    During four consecutive years, 20 durum wheat (Triticum durum Desf) and bread wheat (Triticum aestrivum L.) cultivars were grown under rain-fed conditions and supplementary irrigation with the objective of assessing the possibility of using 13 C discrimination Δ as a criterion to screen for wheat cultivars that produce high yields and have a better water use efficiency under water deficit conditions. In all four growing season, both treatments were subjected to some water stress which was higher under rain-fed conditions and varied according to the intensity and time of rainfall. During the first growing season, and despite small differences between the two treatments in terms of the amounts of water used, the grain and straw yields as well as Δ were significantly higher in the treatment which received an irrigation at installation than in the one without irrigation. There was substantial genotypic variation in Δ. When both treatments were considered, the total above ground dry matter yield and grain yield were positively correlated with Δ although the correlation coefficient of grain yield versus Δ was not high ( ** ). The data suggest that while a high Δ value may be used as a criterion for selection of cultivars of wheat with potential for high yield and high water use efficiency in wheat under field conditions, caution must be exercised in the selection process as the size of the canopy and the changes in environmental factors mainly soil water content, can result in changes in Δ and the yield of a cultivar. However, Δ of a genotype can also provide valuable information with respect to plant parameters responsible for the control of Δ and this information can be usefully employed in breeding programmes aimed at developing wheat cultivars high in yield and high in water use efficiency, and suitable for cultivation in arid and semi-arid regions of the tropics and sub-tropics. 11 refs, 2 figs, 2 tabs

  9. Carbon-13 discrimination as a criterion for identifying high water use efficiency wheat cultivars under water deficit conditions

    Energy Technology Data Exchange (ETDEWEB)

    Bazza, M [Rabat-Institus, Rabat (Morocco). Inst. Agronomique et Veterinaire Hassan II

    1996-07-01

    During four consecutive years, 20 durum wheat (Triticum durum Desf) and bread wheat (Triticum aestrivum L.) cultivars were grown under rain-fed conditions and supplementary irrigation with the objective of assessing the possibility of using {sup 13}C discrimination {Delta} as a criterion to screen for wheat cultivars that produce high yields and have a better water use efficiency under water deficit conditions. In all four growing season, both treatments were subjected to some water stress which was higher under rain-fed conditions and varied according to the intensity and time of rainfall. During the first growing season, and despite small differences between the two treatments in terms of the amounts of water used, the grain and straw yields as well as {Delta} were significantly higher in the treatment which received an irrigation at installation than in the one without irrigation. There was substantial genotypic variation in {Delta}. When both treatments were considered, the total above ground dry matter yield and grain yield were positively correlated with {Delta} although the correlation coefficient of grain yield versus {Delta} was not high (< 0.45{sup **}). The data suggest that while a high {Delta} value may be used as a criterion for selection of cultivars of wheat with potential for high yield and high water use efficiency in wheat under field conditions, caution must be exercised in the selection process as the size of the canopy and the changes in environmental factors mainly soil water content, can result in changes in {Delta} and the yield of a cultivar. But, {Delta} of a genotype can also provide valuable information with respect to plant parameters responsible for the control of {Delta} and this information can be usefully employed in breeding programmes aimed at developing wheat cultivars high in yield and high in water use efficiency, and suitable for cultivation in arid and semi-arid regions of the tropics and sub-tropics. 11 refs,2figs,2tabs.

  10. Altered glycogen metabolism in cultured astrocytes from mice with chronic glutathione deficit; relevance for neuroenergetics in schizophrenia.

    OpenAIRE

    Lavoie, S.; Allaman, I.; Petit, J.M.; Do, K.Q.; Magistretti, P.J.

    2011-01-01

    Neurodegenerative and psychiatric disorders including Alzheimer's, Parkinson's or Huntington's diseases and schizophrenia have been associated with a deficit in glutathione (GSH). In particular, a polymorphism in the gene of glutamate cysteine ligase modulatory subunit (GCLM) is associated with schizophrenia. GSH is the most important intracellular antioxidant and is necessary for the removal of reactive by-products generated by the utilization of glucose for energy supply. Furthermore, gluco...

  11. Response of Jatropha curcas L. to water deficit: Yield, water use efficiency and oilseed characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Abou Kheira, Abdrabbo A. [Water Management Research Institute, National Water Research Center, Delta Barrage, P.O. Box 13621/5 (Egypt); Atta, Nahed M.M. [Oil and Fat Research Department, Food Technology Research Institute, Agricultural Research Center, Giza (Egypt)

    2009-10-15

    Field experiment was carried out at Enshas Experiment Station; Jatropha was transplanted and treated after the second year of the transplanting by different amounts of water stress, viz. 125%, 100%, 75% and 50% of potential evapotranspiration (ETp). The study aims to ensure the multiple benefits of Jatropha and its suitability under Egypt's climate in unused lands under scarce water conditions. The results revealed that the average water consumption rate of Jatropha is 6 L week{sup -1} throughout the growing season, which means that Jatropha can survive and produce full yield with high quality seeds under minimum water requirements compared to other crops. The yield of extracted oil was 85.5, 175.2, 90.5 and 66.5 kg ha{sup -1} at 125%, 100%, 75% and 50% of ETp, respectively. The lowest values of total lipid (oil) (25% and 24.5% of Jatropha seeds) were recorded with Jatropha trees that were irrigated by 125% and 50% of ETp, respectively. On the other hand, the treatment that was irrigated by 100% of ETp (control) recorded the highest value of total oil in the seeds (29.93%). The results also revealed that there are no significant differences among the values of the determined oil characteristics due to different water stress ratios. From the results, it could be concluded that the highest characteristics of Jatropha seed oil were recorded with 100% of ETp. In addition water stress had no significant effect on the fatty acid composition of Jatropha seed oil. (author)

  12. Organ-specific defence strategies of pepper (Capsicum annuum L.) during early phase of water deficit.

    Science.gov (United States)

    Sziderics, Astrid Heide; Oufir, Mouhssin; Trognitz, Friederike; Kopecky, Dieter; Matusíková, Ildikó; Hausman, Jean-Francois; Wilhelm, Eva

    2010-03-01

    Drought is one of the major factors that limits crop production and reduces yield. To understand the early response of plants under nearly natural conditions, pepper plants (Capsicum annuum L.) were grown in a greenhouse and stressed by withholding water for 1 week. Plants adapted to the decreasing water content of the soil by adjustment of their osmotic potential in root tissue. As a consequence of drought, strong accumulation of raffinose, glucose, galactinol and proline was detected in the roots. In contrast, in leaves the levels of fructose, sucrose and also galactinol increased. Due to the water deficit cadaverine, putrescine, spermidine and spermine accumulated in leaves, whereas the concentration of polyamines was reduced in roots. To study the molecular basis of these responses, a combined approach of suppression subtractive hybridisation and microarray technique was performed on the same material. A total of 109 unique ESTs were detected as responsive to drought, while additional 286 ESTs were selected from the bulk of rare transcripts on the array. The metabolic profiles of stressed pepper plants are discussed with respect to the transcriptomic changes detected, while attention is given to the differences between defence strategies of roots and leaves.

  13. Spermidine sprays alleviate the water deficit-induced oxidative stress in finger millet (Eleusine coracana L. Gaertn.) plants.

    Science.gov (United States)

    Satish, Lakkakula; Rency, Arockiam Sagina; Ramesh, Manikandan

    2018-01-01

    Severe drought stress (water deficit) in finger millet ( Eleusine coracana L. Gaertn.) plants significantly reduced total leaf chlorophyll and relative water content in shoots and roots, whereas electrolyte leakage, concentrations of proline and hydrogen peroxide, as well as caspase-like activity were significantly increased. The role of spermidine in plant defence to water-stress was investigated after subjected to various drought treatments. Three weeks of daily spermidine sprays (0.2 mM) at early flowering stage significantly changed shoot and root growth, in both fresh and dry weights terms. At 75% of water deficit stress, leaves accumulated twice as much proline as unstressed plants, and roots accumulated thrice. Plants treated with spermidine under water stress showed lower electrolyte leakage, hydrogen peroxide and caspase-like activity than unstressed and untreated control.

  14. Arabidopsis PCaP2 Functions as a Linker Between ABA and SA Signals in Plant Water Deficit Tolerance

    Directory of Open Access Journals (Sweden)

    Xianling Wang

    2018-05-01

    Full Text Available Water stress has a major influence on plant growth, development, and productivity. However, the cross-talk networks involved in drought tolerance are not well understood. Arabidopsis PCaP2 is a plasma membrane-associated Ca2+-binding protein. In this study, we employ qRT-PCR and β-glucuronidase (GUS histochemical staining to demonstrate that PCaP2 expression was strongly induced in roots, cotyledons, true leaves, lateral roots, and whole plants under water deficit conditions. Compared with the wild type (WT plants, PCaP2-overexpressing (PCaP2-OE plants displayed enhanced water deficit tolerance in terms of seed germination, seedling growth, and plant survival status. On the contrary, PCaP2 mutation and reduction via PCaP2-RNAi rendered plants more sensitive to water deficit. Furthermore, PCaP2-RNAi and pcap2 seedlings showed shorter root hairs and lower relative water content compared to WT under normal conditions and these phenotypes were exacerbated under water deficit. Additionally, the expression of PCaP2 was strongly induced by exogenous abscisic acid (ABA and salicylic acid (SA treatments. PCaP2-OE plants showed insensitive to exogenous ABA and SA treatments, in contrast to the susceptible phenotypes of pcap2 and PCaP2-RNAi. It is well-known that SNF1-related kinase 2s (SnRK2s and pathogenesis-related (PRs are major factors that influence plant drought tolerance by ABA- and SA-mediated pathways, respectively. Interestingly, PCaP2 positively regulated the expression of drought-inducible genes (RD29A, KIN1, and KIN2, ABA-mediated drought responsive genes (SnRK2.2, -2.3, -2.6, ABF1, -2, -3, -4, and SA-mediated drought responsive genes (PR1, -2, -5 under water deficit, ABA, or SA treatments. Taken together, our results showed that PCaP2 plays an important and positive role in Arabidopsis water deficit tolerance by involving in response to both ABA and SA signals and regulating root hair growth. This study provides novel insights into the

  15. Improving yield and water productivity of maize grown under deficit-irrigated in dry area conditions

    Directory of Open Access Journals (Sweden)

    Mohamed H. Abd el-wahed

    2015-10-01

    Full Text Available Scarcity of water is the most severe constraint for development of maize in arid and semi-arid areas. Based on the actual crop need, the irrigation management has to be improved so that the water supply to the crop can be reduced while still achieving high yield. Therefore, the current study has been organized to evaluate the effects of deficit sprinkler irrigation (DSI and farmyard manure (FYM on Grain yield (GY and crop water productivity (CWP of corn, a 2-year experiment was conducted in arid region of Libya. The DSI treatments were (I100 = 100%, I85 = 85% or I70 = 70% of the crop evapotranspiration. FYM treatments were (0, 10 ton ha−1 spread either on the soil surface, incorporated with surface or subsurface layer (FYM10s, FYM10m or FYM10ss, respectively and 20 ton ha−1 spread as before (FYM20s, FYM20m or FYM20ss, respectively. Results indicated that the highest values of grain yield (GY were obtained from I100 treatment, while the lowest were observed in I70. FYM20ss enhanced GY than other FYM treatments in both seasons. The highest GY and CWP were recorded with I100 and received FYM20ss. It could be considered as a suitable under arid environmental conditions and similar regions, the treatment (I100 × FYM20ss is the most suitable for producing high GY and CWP. Under limited irrigation water, application of (I85 ×FYM20ss treatment was found to be favorable to save 15% of the applied irrigation water, at the time in which produced the same GY.

  16. Water deficit imposed by partial irrigation at different plant growth stages of common bean

    International Nuclear Information System (INIS)

    Calvache, M.; Reichardt, K.

    1995-01-01

    The purpose of this study was to identify specific growth stages of common bean crop, at which the plant is less sensitive to water stress so that irrigation can be omitted without significant decrease in biological nitrogen fixation and yield. Two field experiments were conducted at a University experiments station, Tumbaco, Pichincha, Ecuador, on a sandy loam soil ( Typic durustoll ). The climate is warm and dry ( mean air temperature 16 degree Celcius and mean relative humidity 74% ) during the cropping season and rainfall of 123 mm was recorded during the cropping period. The treatments consisted of combinations of 7 irrigation regimes ( I1 = all normal watering; I2 = all stres; I3 = traditional practice; I4 = single stress at vegetation; I5 flowering; I6 = yield formation and I7 = ripening stages ) and 2 levels of applied N ( 20 and 80 kg/ ha ). Differential irrigation was started after 3 uniform irrigations for germination and crop establishment. Soil moisture was monitored with a neutron probe down to 0.60 m depth, before and 24 h after each irrigation. Biological Nitrogen Fixation was calculated using the N- 15 metodology in the 20 kg N/ ha treatment. From the yield data, it can be concluded that treatments which had irrigation deficit had lower yield than those that had suplementary irrigation. The flowering stage was the most sensitive to number of pods and grain yield. Biological Nitrogen Fixation was significantly affected by water stress at flowering and formation stages. The crop water use efficiency ( kg/ m 3 ) was the lowest at flowering period and the yield response factor ( Ky ) was higher in treatments I2 ( all stress ) and I5 (stress at flowering ). Comparing with traditional practice by farmers of the region, only treatments I1 and I7 had 13 and 10 % higher crop water use effeciency. 15 tabs., 7 refs. ( Author )

  17. Water masses in the Humboldt Current System: Properties, distribution, and the nitrate deficit as a chemical water mass tracer for Equatorial Subsurface Water off Chile

    Science.gov (United States)

    Silva, Nelson; Rojas, Nora; Fedele, Aldo

    2009-07-01

    Three sections are used to analyze the physical and chemical characteristics of the water masses in the eastern South Pacific and their distributions. Oceanographic data were taken from the SCORPIO (May-June 1967), PIQUERO (May-June 1969), and KRILL (June 1974) cruises. Vertical sections of temperature, salinity, σ θ, dissolved oxygen, nitrate, nitrite, phosphate, and silicate were used to analyze the water column structure. Five water masses were identified in the zone through T- S diagrams: Subantarctic Water, Subtropical Water, Equatorial Subsurface Water, Antarctic Intermediate Water, and Pacific Deep Water. Their proportions in the sea water mixture are calculated using the mixing triangle method. Vertical sections were used to describe the geographical distributions of the water mass cores in the upper 1500 m. Several characteristic oceanographic features in the study area were analyzed: the shallow salinity minimum displacement towards the equator, the equatorial subsurface salinity maximum associated with a dissolved oxygen minimum zone and a high nutrient content displacement towards the south, and the equatorward intermediate Antarctic salinity minimum associated with a dissolved oxygen maximum. The nitrate deficit generated in the denitrification area off Peru and northern Chile is proposed as a conservative chemical tracer for the Equatorial Subsurface Waters off the coast of Chile, south of 25°S.

  18. Moderate water stress from regulated deficit irrigation decreases transpiration similarly to net carbon exchange in grapevine canopies

    Science.gov (United States)

    To determine the effects of timing and extent of regulated deficit irrigation (RDI) on grapevine (Vitis vinifera) canopies, whole-canopy transpiration (TrV) and canopy conductance to water vapor (gc) were calculated from whole-vine gas exchange near key stages of fruit development. The vines were ma...

  19. Genomic Architecture and Phenotypic Plasticity of Forage Quality in Response to Water Deficit in Alfalfa (Medicago sativa L.)

    Science.gov (United States)

    A panel of alfalfa cultivars and landraces originated worldwide with potential value of drought tolerance were selected from USDA-Western Region Plant Germplasm Center. Field trials were conducted in the in Roza farm in Prosser, WA and a gradient of water deficits were applied. Aboveground biomass w...

  20. Rapid and long-term effects of water deficit on gas exchange and hydraulic conductance of silver birch trees grown under varying atmospheric humidity.

    Science.gov (United States)

    Sellin, Arne; Niglas, Aigar; Õunapuu-Pikas, Eele; Kupper, Priit

    2014-03-24

    Effects of water deficit on plant water status, gas exchange and hydraulic conductance were investigated in Betula pendula under artificially manipulated air humidity in Eastern Estonia. The study was aimed to broaden an understanding of the ability of trees to acclimate with the increasing atmospheric humidity predicted for northern Europe. Rapidly-induced water deficit was imposed by dehydrating cut branches in open-air conditions; long-term water deficit was generated by seasonal drought. The rapid water deficit quantified by leaf (ΨL) and branch water potentials (ΨB) had a significant (P gas exchange parameters, while inclusion of ΨB in models resulted in a considerably better fit than those including ΨL, which supports the idea that stomatal openness is regulated to prevent stem rather than leaf xylem dysfunction. Under moderate water deficit (ΨL≥-1.55 MPa), leaf conductance to water vapour (gL), transpiration rate and leaf hydraulic conductance (KL) were higher (P water deficit (ΨLwater availability, i.e. due to higher soil water potential in H treatment. Two functional characteristics (gL, KL) exhibited higher (P water deficit in trees grown under increased air humidity. The experiment supported the hypothesis that physiological traits in trees acclimated to higher air humidity exhibit higher sensitivity to rapid water deficit with respect to two characteristics - leaf conductance to water vapour and leaf hydraulic conductance. Disproportionate changes in sensitivity of stomatal versus leaf hydraulic conductance to water deficit will impose greater risk of desiccation-induced hydraulic dysfunction on the plants, grown under high atmospheric humidity, in case of sudden weather fluctuations, and might represent a potential threat in hemiboreal forest ecosystems. There is no trade-off between plant hydraulic capacity and photosynthetic water-use efficiency on short time scale.

  1. Effect of readily available water deficit in soil on maize yield and evapotranspiration

    Directory of Open Access Journals (Sweden)

    Pejić Borivoj

    2010-01-01

    Full Text Available An investigation was carried out at Rimski Šančevi experiment field of Institute of Field and Vegetable Crops, Novi Sad on calcareous chernozem soil on the loess terrace, in the period 2000-2007, and included irrigated variant (T1 and non-irrigated i.e. control variant (T0. NS-640, maize hybrid from the FAO maturity group 600, was analyzed. Readily available soil water deficit (RASWD in the layer of 60 cm in the course of growing season and actual evapotranspiration (ETa were calculated by the water balance method. Water consumption for potential evapotranspiration (ETm in individual months and the growing season were calculated by the bioclimatic procedure, using hydrophytothermic indexes. The correlation analysis revealed highly significant dependences of maize yield (Y on RASWD (r = -0.941 and the amount of precipitation (P in August (r = 0.931. Statistically significant dependence was also found between Y and RASWD (r = -0.765 and P (r = 0.768 in July and August. The obtained results indicate that maize production in Vojvodina under the rainfed conditions is unreliable, and that it is correlated with weather conditions, especially with the amount and distribution of precipitation. The statistically significant correlation obtained between Y and ETa (r = 0.755 confirms that water supply is the basic prerequisite which allows the other production factors to be realized. Significantly higher maize yields in the T1 variant (13.517 t ha-1 in relation to the T0 variant (11.210 t ha-1 indicate clearly that under the climatic conditions of Vojvodina high and stable yields of maize can be achieved only in irrigation. .

  2. Molecular Characterization and Germination Analysis of Cotton (Gossypium hirsutum L. Genotypes under Water Deficit Irrigation

    Directory of Open Access Journals (Sweden)

    Eminur ELÇİ

    2016-09-01

    Full Text Available Cotton is an important crop in terms of economic and strategic impacts. Drought stress is one of the most important environmental stress factors which negatively affects growth and yield of plants in Turkey as occurred in many countries in the world. In this study, 11 different cotton cultivars selected based on their agronomical characters were tested under water deficit irrigation strategies. Thus, it was aimed to select and/or determine appropriate new varieties for breeding new national materials resistant to drought stress, and to characterize with the molecular microsatellite markers. According to the different irrigation levels (25%, 50%, 75% and 100% plants were observed under the stressed conditions at the irrigation levels of 50% and 25%. Among the tested varieties, Tamcot Sphinx, Tamcot 94, Tamcot CamdEs and BA525 varieties were found to be more water stress tolerant than others in terms of germination time and germinated plant. The UPGMA (Unweighted Pair-Group Method Using Arithmetic Averages analysis was carried out using 28 markers with average 0.306 polymorphism information content (PIC for molecular characterization studies. Based on the UPGMA results, the varieties were clustered into two groups. It is expected that the results obtained from this study might provide considerable data for improving new drought tolerant varieties.

  3. The shift from plant-plant facilitation to competition under severe water deficit is spatially explicit.

    Science.gov (United States)

    O'Brien, Michael J; Pugnaire, Francisco I; Armas, Cristina; Rodríguez-Echeverría, Susana; Schöb, Christian

    2017-04-01

    The stress-gradient hypothesis predicts a higher frequency of facilitative interactions as resource limitation increases. Under severe resource limitation, it has been suggested that facilitation may revert to competition, and identifying the presence as well as determining the magnitude of this shift is important for predicting the effect of climate change on biodiversity and plant community dynamics. In this study, we perform a meta-analysis to compare temporal differences of species diversity and productivity under a nurse plant ( Retama sphaerocarpa ) with varying annual rainfall quantity to test the effect of water limitation on facilitation. Furthermore, we assess spatial differences in the herbaceous community under nurse plants in situ during a year with below-average rainfall. We found evidence that severe rainfall deficit reduced species diversity and plant productivity under nurse plants relative to open areas. Our results indicate that the switch from facilitation to competition in response to rainfall quantity is nonlinear. The magnitude of this switch depended on the aspect around the nurse plant. Hotter south aspects under nurse plants resulted in negative effects on beneficiary species, while the north aspect still showed facilitation. Combined, these results emphasize the importance of spatial heterogeneity under nurse plants for mediating species loss under reduced precipitation, as predicted by future climate change scenarios. However, the decreased water availability expected under climate change will likely reduce overall facilitation and limit the role of nurse plants as refugia, amplifying biodiversity loss.

  4. Altered cerebellar development in nuclear receptor TAK1/ TR4 null mice is associated with deficits in GLAST(+) glia, alterations in social behavior, motor learning, startle reactivity, and microglia.

    Science.gov (United States)

    Kim, Yong-Sik; Harry, G Jean; Kang, Hong Soon; Goulding, David; Wine, Rob N; Kissling, Grace E; Liao, Grace; Jetten, Anton M

    2010-09-01

    Previously, deficiency in the expression of the nuclear orphan receptor TAK1 was found to be associated with delayed cerebellar granule cell migration and Purkinje cell maturation with a permanent deficit in foliation of lobules VI–VII, suggesting a role for TAK1 in cerebellum development. In this study, we confirm that TAK1-deficient (TAK1(−/−)) mice have a smaller cerebellum and exhibit a disruption of lobules VI–VII. We extended these studies and show that at postnatal day 7, TAK1(−/−) mice exhibit a delay in monolayer maturation of dysmorphic calbindin 28K-positive Purkinje cells. The astrocyte-specific glutamate transporter (GLAST) was expressed within Bergmann fibers and internal granule cell layer at significantly lower levels in the cerebellum of TAK1(−/−) mice. At PND21, Golgi-positive Purkinje cells in TAK1(−/−) mice displayed a smaller soma (18%) and shorter distance to first branch point (35%). Neuronal death was not observed in TAK1(−/−) mice at PND21; however, activated microglia were present in the cerebellum, suggestive of earlier cell death. These structural deficits in the cerebellum were not sufficient to alter motor strength, coordination, or activity levels; however, deficits in acoustic startle response, prepulse startle inhibition, and social interactions were observed. Reactions to a novel environment were inhibited in a light/dark chamber, open-field, and home-cage running wheel. TAK1(−/−) mice displayed a plateau in performance on the running wheel, suggesting a deficit in learning to coordinate performance on a motor task. These data indicate that TAK1 is an important transcriptional modulator of cerebellar development and neurodevelopmentally regulated behavior.

  5. Remobilisation of carbon and nitrogen supports seed filling in chickpea subjected to water deficit

    International Nuclear Information System (INIS)

    Davies, S.L.; Plummer, J.A.

    2000-01-01

    In the Mediterranean-type environment of south-western Australia, pod filling of chickpea occurs when net photosynthesis and nitrogen fixation is low as a result of the onset of terminal drought. Remobilization of carbon (C) and nitrogen (N) from vegetative parts to developing seed may be an important alternative source of C and N for seed filling. The contribution of stored pre-podding C and N to seed filling was studied by labelling the vegetative tissues with the stable isotopes, 13 C and 15 N, prior to podding and following their subsequent movement to the seed. In ICCV88201, an advanced desi breeding line, 9% of the C and 67% of the N in the seed were derived from pre-podding C and N in well-watered plants compared with 13% of the seed C and 88% of the seed N in water-stressed plants. Furthermore, the contribution of pre-podding C and N was higher for earlier set compared with later set seeds. Pre-podding C and N were derived predominantly from the leaves with relatively little from the stems, roots, and pod walls. Genotypic variation in remobilization ability was identified in contrasting desi (Tyson) and kabuli (Kaniva) cultivars. In well-watered Tyson, 9% of the seed C and 85% of the seed N were remobilised from vegetative tissues compared with 7% of the seed C and 62% of seed N in well-watered Kaniva. Water deficit decreased the amount of C remobilized by 3% in Tyson compared with 66% in Kaniva, whereas the total amount of N remobilized was decreased by 11% in Tyson and 48% in Kaniva. This was related to the maintenance of greater sink strength in Tyson, in which the number of filled pods was reduced by 66% in stressed plants compared with a 91% decrease in Kaniva. This indicates that better drought tolerance in desi genotypes is partly a consequence of better remobilization and higher pod number. These studies show that C and N assimilated prior to podding can supplement the supply of current assimilates to the filling seed in both well-watered and water

  6. Dynamic changes in the leaf proteome of a C3 xerophyte, Citrullus lanatus (wild watermelon), in response to water deficit.

    Science.gov (United States)

    Akashi, Kinya; Yoshida, Kazuo; Kuwano, Masayoshi; Kajikawa, Masataka; Yoshimura, Kazuya; Hoshiyasu, Saki; Inagaki, Naoyuki; Yokota, Akiho

    2011-05-01

    Wild watermelon (Citrullus lanatus) is a xerophyte native to the Kalahari Desert, Africa. To better understand the molecular mechanisms of drought resistance in this plant, we examined changes in the proteome in response to water deficit. Wild watermelon leaves showed decreased transpiration and a concomitant increase in leaf temperature under water deficit conditions. Comparison of the proteome of stressed plants with that of unstressed plants by two-dimensional gel electrophoresis revealed that the intensity of 40 spots increased in response to the stress, and the intensity of 11 spots decreased. We positively identified 23 stress-induced and 6 stress-repressed proteins by mass spectrometry and database analyses. Interestingly, 15 out of the 23 up-regulated proteins (65% of annotated up-regulated proteins) were heat shock proteins (HSPs). Especially, 10 out of the 15 up-regulated HSPs belonged to the small heat shock protein (sHSP) family. Other stress-induced proteins included those related to antioxidative defense and carbohydrate metabolism. Fifteen distinct cDNA sequences encoding the sHSP were characterized from wild watermelon. Quantitative real-time PCR analysis of the representative sHSP genes revealed strong transcriptional up-regulation in the leaves under water deficit. Moreover, immunoblot analysis confirmed that protein abundance of sHSPs was massively increased under water deficit. Overall, these observations suggest that the defense response of wild watermelon may involve orchestrated regulation of a diverse array of functional proteins related to cellular defense and metabolism, of which HSPs may play a pivotal role on the protection of the plant under water deficit in the presence of strong light.

  7. Gray matter deficits and altered resting-state connectivity in the superior temporal gyrus among individuals with problematic hypersexual behavior.

    Science.gov (United States)

    Seok, Ji-Woo; Sohn, Jin-Hun

    2018-04-01

    Neuroimaging studies on the characteristics of hypersexual disorder have been accumulating, yet alternations in brain structures and functional connectivity in individuals with problematic hypersexual behavior (PHB) has only recently been studied. This study aimed to investigate gray matter deficits and resting-state abnormalities in individuals with PHB using voxel-based morphometry and resting-state connectivity analysis. Seventeen individuals with PHB and 19 age-matched healthy controls participated in this study. Gray matter volume of the brain and resting-state connectivity were measured using 3T magnetic resonance imaging. Compared to healthy subjects, individuals with PHB had significant reductions in gray matter volume in the left superior temporal gyrus (STG) and right middle temporal gyrus. Individuals with PHB also exhibited a decrease in resting-state functional connectivity between the left STG and left precuneus and between the left STG and right caudate. The gray matter volume of the left STG and its resting-state functional connectivity with the right caudate both showed significant negative correlations with the severity of PHB. The findings suggest that structural deficits and resting-state functional impairments in the left STG might be linked to PHB and provide new insights into the underlying neural mechanisms of PHB. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Effects of Soil Water Deficit on Insecticidal Protein Expression in Boll Shells of Transgenic Bt Cotton and the Mechanism

    Directory of Open Access Journals (Sweden)

    Xiang Zhang

    2017-12-01

    Full Text Available This study was conducted to investigate the effects of soil water deficit on insecticidal protein expression in boll shells of cotton transgenic for a Bt gene. In 2014, Bt cotton cultivars Sikang 1 (a conventional cultivar and Sikang 3 (a hybrid cultivar were planted in pots and five soil water content treatments were imposed at peak boll stage: 15% (G1, 35% (G2, 40% (G3, 60% (G4, and 75% field capacity (CK, respectively. Four treatments (G2, G3, G4, and CK were repeated in 2015 in the field. Results showed that the insecticidal protein content of boll shells decreased with increasing water deficit. Compared with CK, boll shell insecticidal protein content decreased significantly when soil water content was below 60% of maximum water holding capacity for Sikang 1 and Sikang 3. However, increased Bt gene expression was observed when boll shell insecticidal protein content was significantly reduced. Activity assays of key enzymes in nitrogen metabolism showed that boll shell protease and peptidase increased but nitrogen reductase and glutamic-pyruvic transaminase (GPT decreased. Insecticidal protein content exhibited significant positive correlation with nitrogen reductase and GPT activities; and significant negative correlation with protease and peptidase activities. These findings suggest that the decrease of insecticidal protein content associated with increasing water deficit was a net result of decreased synthesis and increased decomposition.

  9. RNA-Seq reveals genotype-specific molecular responses to water deficit in eucalyptus

    Science.gov (United States)

    2011-01-01

    Background In a context of climate change, phenotypic plasticity provides long-lived species, such as trees, with the means to adapt to environmental variations occurring within a single generation. In eucalyptus plantations, water availability is a key factor limiting productivity. However, the molecular mechanisms underlying the adaptation of eucalyptus to water shortage remain unclear. In this study, we compared the molecular responses of two commercial eucalyptus hybrids during the dry season. Both hybrids differ in productivity when grown under water deficit. Results Pyrosequencing of RNA extracted from shoot apices provided extensive transcriptome coverage - a catalog of 129,993 unigenes (49,748 contigs and 80,245 singletons) was generated from 398 million base pairs, or 1.14 million reads. The pyrosequencing data enriched considerably existing Eucalyptus EST collections, adding 36,985 unigenes not previously represented. Digital analysis of read abundance in 14,460 contigs identified 1,280 that were differentially expressed between the two genotypes, 155 contigs showing differential expression between treatments (irrigated vs. non irrigated conditions during the dry season), and 274 contigs with significant genotype-by-treatment interaction. The more productive genotype displayed a larger set of genes responding to water stress. Moreover, stress signal transduction seemed to involve different pathways in the two genotypes, suggesting that water shortage induces distinct cellular stress cascades. Similarly, the response of functional proteins also varied widely between genotypes: the most productive genotype decreased expression of genes related to photosystem, transport and secondary metabolism, whereas genes related to primary metabolism and cell organisation were over-expressed. Conclusions For the most productive genotype, the ability to express a broader set of genes in response to water availability appears to be a key characteristic in the maintenance

  10. Untangling the effects of shallow groundwater and deficit irrigation on irrigation water productivity in arid region: New conceptual model.

    Science.gov (United States)

    Xue, Jingyuan; Huo, Zailin; Wang, Fengxin; Kang, Shaozhong; Huang, Guanhua

    2018-04-01

    Water scarcity and salt stress are two main limitations for agricultural production. Groundwater evapotranspiration (ET g ) with upward salt movement plays an important role in crop water use and water productivity in arid regions, and it can compensate the impact of deficit irrigation on crop production. Thus, comprehensive impacts of shallow groundwater and deficit irrigation on crop water use results in an improvement of irrigation water productivity (IWP). However, it is difficult to quantify the effects of groundwater and deficit irrigation on IWP. In this study, we built an IWP evaluation model coupled with a water and salt balance model and a crop yield estimation model. As a valuable tool of IWP simulation, the calibrated model was used to investigate the coupling response of sunflower IWP to irrigation water depths (IWDs), groundwater table depth (GTDs) and groundwater salinities (GSs). A total of 210 scenarios were run in which five irrigation water depths (IWDs) and seven groundwater table depths (GTDs) and six groundwater salinities (GSs) were used. Results indicate that increasing GS clearly increases the negative effect on a crop's actual evapotranspiration (ET a ) as salt accumulation in root zone. When GS is low (0.5-1g/L), increasing GTD produces more positive effect than negative effect. In regard to relatively high GS (2-5g/L), the negative effect of shallow-saline groundwater reaches a maximum at 2m GTD. Additionally, the salt concentration in the root zone maximizes its value at 2.0m GTD. In most cases, increasing GTD and GS reduces the benefits of irrigation water and IWP. The IWP increases with decreasing irrigation water. Overall, in arid regions, capillary rise of shallow groundwater can compensate for the lack of irrigation water and improve IWP. By improving irrigation schedules and taking advantages of shallow saline groundwater, we can obtain higher IWP. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Water deficits and heat shock effects on photosynthesis of a transgenic Arabidopsis thaliana constitutively expressing ABP9, a bZIP transcription factor

    DEFF Research Database (Denmark)

    Zhang, Xia; Wollenweber, Bernd; Jiang, Dong

    2008-01-01

    The effects of water deficits (WD), heat shock (HS), and both (HSWD) on photosynthetic carbon- and light-use efficiencies together with leaf ABA content, pigment composition and expressions of stress- and light harvesting-responsive genes were investigated in ABP9 [ABA-responsive-element (ABRE...... transport rate (ETR) in 5P2 plants were depressed under optimal growth conditions (control) in relation to WT, they were enhanced under HS and HSWD. These results indicate that ABP9 transgenic plants are less susceptible to stress than the WT. In addition, the increased ABA contents in both WT and 5P2......, altered expression of stress-regulated or light harvesting-responsive genes was observed. Collectively, our results indicate that constitutive expression of ABP9 improves the photosynthetic capacity of plants under stress by adjusting photosynthetic pigment composition, dissipating excess light energy...

  12. Effect of phosphate solubilizing microorganisms on quantitative and qualitative characteristics of maize (Zea mays L.) under water deficit stress.

    Science.gov (United States)

    Ehteshami, S M R; Aghaalikhani, M; Khavazi, K; Chaichi, M R

    2007-10-15

    The effect of seed inoculation by phosphate solubilizing microorganisms on growth, yield and nutrient uptake of maize (Zea mays L. SC. 704) was studied in a field experiment. Positive effect on plant growth, nutrient uptake, grain yield and yield components in maize plants was recorded in the treatment receiving mixed inoculum of Glomus intraradices (AM) and Pseudomonas fluorescens (Pf). Co-inoculation treatment significantly increased grain yield, yield components, harvest index, grain N and P, soil available P, root colonization percentage and crop WUE under water deficit stress. In some of investigated characteristics under well-watered conditions, chemical fertilizer treatment was higher than double inoculated treatments, but this difference was not significant. Seed inoculation only with AM positively affected the measured parameters as amount as co-inoculated treatments. According to the results showed in contrast to the inoculated treatments with AM+Pf and AM, the application of alone Pf caused a comparatively poor response. Therefore, this microorganism needs to a complement for its activity in soil. All of measured parameters in inoculated treatments were higher than uninoculated treatments under water deficit stress conditions. Furthermore, the investigated characteristics of co-inoculated plants under severe water deficit stress conditions were significantly lower than co-inoculated plants under well-watered and moderate-stressed conditions. Therefore it could be stated, these microorganisms need more time to fix and establishing themselves in soil. The present finding showed that phosphate-solubilizing microorganisms can interact positively in promoting plant growth as well as P uptake of maize plants, leading to plant tolerance improving under water deficit stress conditions.

  13. Differences in proleptic and epicormic shoot structures in relation to water deficit and growth rate in almond trees (Prunus dulcis).

    Science.gov (United States)

    Negrón, Claudia; Contador, Loreto; Lampinen, Bruce D; Metcalf, Samuel G; Guédon, Yann; Costes, Evelyne; DeJong, Theodore M

    2014-02-01

    Shoot characteristics differ depending on the meristem tissue that they originate from and environmental conditions during their development. This study focused on the effects of plant water status on axillary meristem fate and flowering patterns along proleptic and epicormic shoots, as well as on shoot growth rates on 'Nonpareil' almond trees (Prunus dulcis). The aims were (1) to characterize the structural differences between proleptic and epicormic shoots, (2) to determine whether water deficits modify shoot structures differently depending on shoot type, and (3) to determine whether shoot structures are related to shoot growth rates. A hidden semi-Markov model of the axillary meristem fate and number of flower buds per node was built for two shoot types growing on trees exposed to three plant water status treatments. The models segmented observed shoots into successive homogeneous zones, which were compared between treatments. Shoot growth rates were calculated from shoot extension measurements made during the growing season. Proleptic shoots had seven successive homogeneous zones while epicormic shoots had five zones. Shoot structures were associated with changes in growth rate over the season. Water deficit (1) affected the occurrence and lengths of the first zones of proleptic shoots, but only the occurrence of the third zone was reduced in epicormic shoots; (2) had a minor effect on zone flowering patterns and did not modify shoot or zone composition of axillary meristem fates; and (3) reduced growth rates, although patterns over the season were similar among treatments. Two meristem types, with different latency durations, produced shoots with different growth rates and distinct structures. Differences between shoot type structure responses to water deficit appeared to reflect their ontogenetic characteristics and/or resource availability for their development. Tree water deficit appeared to stimulate a more rapid progression through ontogenetic states.

  14. Altered interregional molecular associations of the serotonin transporter in attention deficit/hyperactivity disorder assessed with PET.

    Science.gov (United States)

    Vanicek, Thomas; Kutzelnigg, Alexandra; Philippe, Cecile; Sigurdardottir, Helen L; James, Gregory M; Hahn, Andreas; Kranz, Georg S; Höflich, Anna; Kautzky, Alexander; Traub-Weidinger, Tatjana; Hacker, Marcus; Wadsak, Wolfgang; Mitterhauser, Markus; Kasper, Siegfried; Lanzenberger, Rupert

    2017-02-01

    Altered serotonergic neurotransmission has been found to cause impulsive and aggressive behavior, as well as increased motor activity, all exemplifying key symptoms of ADHD. The main objectives of this positron emission tomography (PET) study were to investigate the serotonin transporter binding potential (SERT BP ND ) in patients with ADHD and to assess associations of SERT BP ND between the brain regions. 25 medication-free patients with ADHD (age ± SD; 32.39 ± 10.15; 10 females) without any psychiatric comorbidity and 25 age and sex matched healthy control subjects (33.74 ± 10.20) were measured once with PET and the highly selective and specific radioligand [ 11 C]DASB. SERT BP ND maps in nine a priori defined ROIs exhibiting high SERT binding were compared between groups by means of a linear mixed model. Finally, adopted from structural and functional connectivity analyses, we performed correlational analyses using regional SERT binding potentials to examine molecular interregional associations between all selected ROIs. We observed significant differences in the interregional correlations between the precuneus and the hippocampus in patients with ADHD compared to healthy controls, using SERT BP ND of the investigated ROIs (P < 0.05; Bonferroni corrected). When correlating SERT BP ND and age in the ADHD and the healthy control group, we confirmed an age-related decline in brain SERT binding in the thalamus and insula (R 2  = 0.284, R 2  = 0.167, Ps < 0.05; Bonferroni corrected). The results show significantly different interregional molecular associations of the SERT expression for the precuneus with hippocampus in patients with ADHD, indicating presumably altered functional coupling. Altered interregional coupling between brain regions might be a sensitive approach to demonstrate functional and molecular alterations in psychiatric conditions. Hum Brain Mapp 38:792-802, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley

  15. Water Phase Diagram Is Significantly Altered by Imidazolium Ionic Liquid

    DEFF Research Database (Denmark)

    Chaban, V. V.; Prezhdo, O. V.

    2014-01-01

    We report unusually large changes in the boiling temperature, saturated vapor pressure, and structure of the liquid-vapor interface for a range of 1-butyl-3-methyl tetrafluoroborate, [C4C1IM][BF4]-water mixtures. Even modest molar fractions of [C4C1IM][BF4] significantly affect the phase behavior...... of water, as represented, for instance, by strong negative deviations from Raoult's law, extending far beyond the standard descriptions. The investigation was carried out using classical molecular dynamics employing a specifically refined force field. The changes in the liquid-vapor interface and saturated...

  16. Response of water deficit regime and soil amelioration on evapotranspiration loss and water use efficiency of maize ( Zea mays l.) in subtropical northeastern Himalayas

    Science.gov (United States)

    Marwein, M. A.; Choudhury, B. U.; Chakraborty, D.; Kumar, M.; Das, A.; Rajkhowa, D. J.

    2017-05-01

    Rainfed maize production in the hilly ecosystem of Northeastern Himalayas often suffers from moisture and soil acidity induced abiotic stresses. The present study measured evapotranspiration loss (ETc) of maize crop under controlled condition (pot experiment) of water deficit (W25-25 % and W50-50 % of field capacity soil moistures) and well watered (W100 = 100 % of field capacity (FC)) regimes in strong acid soils (pH = 4.3) of the Northeastern Himalayan Region of India. The response of soil ameliorants (lime) and phosphorus (P) nutrition under differential water regimes on ETc losses and water use efficiency was also studied. The measured seasonal ETc loss varied from 124.3 to 270.9 mm across treatment combinations. Imposition of water deficit stress resulted in significant ( p < 0.05) reduction (by 33-50 %) of seasonal ETc losses but was at the cost of delay in tasseling to silking, 47-65 % reduction in dry matter accumulation (DMA), 12-22 days shortening of grain formation period, and complete kernel abortion. Liming @ 4 t ha-1 significantly ( p < 0.05) increased ETc losses and DMA across water regimes but the magnitude of increase was higher in severely water deficit (W25) regime. Unlike lime, P nutrition improved DMA only in well-watered regimes (W100) while seasonal ETc loss was unaffected. Vegetative stage (tillering to tasseling) contributed the maximum ETc losses while weekly crop ETc loss was estimated highest during 11th-14th week after sowing (coincided with blistering stage) and then declined. Water use efficiency estimated from dry matter produced per unit ETc losses and irrigation water used varied from 4.33 to 9.43 g dry matter kg-1 water and 4.21 to 8.56 g dry matter kg-1, respectively. Among the input factors (water, P, and lime), water regime most strongly influenced the ETc loss, growth duration, grain formation, and water use efficiency of maize.

  17. Satellite Estimation of Daily Land Surface Water Vapor Pressure Deficit from AMSR- E

    Science.gov (United States)

    Jones, L. A.; Kimball, J. S.; McDonald, K. C.; Chan, S. K.; Njoku, E. G.; Oechel, W. C.

    2007-12-01

    Vapor pressure deficit (VPD) is a key variable for monitoring land surface water and energy exchanges, and estimating plant water stress. Multi-frequency day/night brightness temperatures from the Advanced Microwave Scanning Radiometer on EOS Aqua (AMSR-E) were used to estimate daily minimum and average near surface (2 m) air temperatures across a North American boreal-Arctic transect. A simple method for determining daily mean VPD (Pa) from AMSR-E air temperature retrievals was developed and validated against observations across a regional network of eight study sites ranging from boreal grassland and forest to arctic tundra. The method assumes that the dew point and minimum daily air temperatures tend to equilibrate in areas with low night time temperatures and relatively moist conditions. This assumption was tested by comparing the VPD algorithm results derived from site daily temperature observations against results derived from AMSR-E retrieved temperatures alone. An error analysis was conducted to determine the amount of error introduced in VPD estimates given known levels of error in satellite retrieved temperatures. Results indicate that the assumption generally holds for the high latitude study sites except for arid locations in mid-summer. VPD estimates using the method with AMSR-E retrieved temperatures compare favorably with site observations. The method can be applied to land surface temperature retrievals from any sensor with day and night surface or near-surface thermal measurements and shows potential for inferring near-surface wetness conditions where dense vegetation may hinder surface soil moisture retrievals from low-frequency microwave sensors. This work was carried out at The University of Montana, at San Diego State University, and at the Jet Propulsion Laboratory, California Institute of Technology, under contract to the National Aeronautics and Space Administration.

  18. Free proline accumulation in leaves of cultivated plant species under water deficit conditions

    Directory of Open Access Journals (Sweden)

    Hanna Bandurska

    2013-12-01

    Full Text Available The effect of water deficit caused by soil drought on the content of free proline as well as the degree of cell membrane damages in the leaves of three cultivated plant species having different farm usefulness and water requirements have been studied. The used pIants were: poinsettia (Euphorbia pulcherrima Willd., 'Regina' and 'Cortez' grown for decorative purposes, a green vegetable of broccoli (Brassica oleracea var. botrytis, subvar. cymosa, 'Colonel' and 'Marathon' and a cereal plant of barley (the wild form Hordeum spontaneumm and Hordeum vulgaree 'Maresi'. The examined species differed in the size of the experienced stress. the Iargest RWC reduction was found iii broccoli leaves, while somewhat smaller - in barley. In poinsettia leaves, the reduction of RWC level was not large or did not occur at all. The accumulation of free proline in the species under study was also variable. The largest amount of this amino acid tended to accumulate in broccoli leaves, whereas the increase of its level took place only at a strong dehydration of tissues. The increase of proline level was smaller in barley leaves than in broccoli, but that was found already at a smalI dehydration of tissues. In poinsettia leaves, a several f`old increase of proline level was found at the early stage of the stress. The level of that amino acid gradually increased at consecutive times and did not depend on tissue dehydration. Damage of cell membranes amounted to 8.5-9.5% in barley leaves, about 3% in brocolli and to 0-2.6% in poinsettia. The role of proline in prevention of leaf dehydration and in alleviation of dehydration effects in the studied species has been discussed.

  19. Water deficit mechanisms in perennial shrubs Cerasus humilis leaves revealed by physiological and proteomic analyses.

    Science.gov (United States)

    Yin, Zepeng; Ren, Jing; Zhou, Lijuan; Sun, Lina; Wang, Jiewan; Liu, Yulong; Song, Xingshun

    2016-01-01

    Drought (Water deficit, WD) poses a serious threat to extensively economic losses of trees throughout the world. Chinese dwarf cherry ( Cerasus humilis ) is a good perennial plant for studying the physiological and sophisticated molecular network under WD. The aim of this study is to identify the effect of WD on C. humilis through physiological and global proteomics analysis and improve understanding of the WD resistance of plants. Currently, physiological parameters were applied to investigate C. humilis response to WD. Moreover, we used two-dimensional gel electrophoresis (2DE) to identify differentially expressed proteins in C. humilis leaves subjected to WD (24 d). Furthermore, we also examined the correlation between protein and transcript levels. Several physiological parameters, including relative water content and Pn were reduced by WD. In addition, the malondialdehyde (MDA), relative electrolyte leakage (REL), total soluble sugar, and proline were increased in WD-treated C. humilis . Comparative proteomic analysis revealed 46 protein spots (representing 43 unique proteins) differentially expressed in C. humilis leaves under WD. These proteins were mainly involved in photosynthesis, ROS scavenging, carbohydrate metabolism, transcription, protein synthesis, protein processing, and nitrogen and amino acid metabolisms, respectively. WD promoted the CO 2 assimilation by increase light reaction and Calvin cycle, leading to the reprogramming of carbon metabolism. Moreover, the accumulation of osmolytes (i.e., proline and total soluble sugar) and enhancement of ascorbate-glutathione cycle and glutathione peroxidase/glutathione s-transferase pathway in leaves could minimize oxidative damage of membrane and other molecules under WD. Importantly, the regulation role of carbohydrate metabolisms (e. g. glycolysis, pentose phosphate pathways, and TCA) was enhanced. These findings provide key candidate proteins for genetic improvement of perennial plants metabolism under

  20. Effects of water quality alterations on fish behavior

    International Nuclear Information System (INIS)

    Gray, R.H.; Haynes, J.M.; Montgomery, J.C.; Genoway, R.G.; Barraclough, S.A.; Anderson, D.R.; Thatcher, T.O.; Bean, R.M.; Page, T.L.

    1977-01-01

    Objectives of this project are to study behavioral patterns of ecologically or economically valuable fish. Information on sensory--avoidance behavior, or preferential foraging habits, if definitively established by systematic observation can be constructively used in both outfall and water intake design to ameliorate potentially noxious disturbances caused by these structures. The work is applicable to both nuclear and fossil fuel-fired steam electric plants. The instantaneous response of juvenile chinook salmon encountering a simulated river thermal plume interface was also evaluated in a model raceway. Tests indicate that juvenile chinook salmon perceive and avoid discharge temperatures greater than 9 to 11 0 C above ambient, regardless of acclimation temperature. Chlorine is a major chemical compound to reduce biofouling in steam electric power plants. Chlorination of large volumes of cooling waters poses the problem of the formation of chlorination by-products discharged to natural water systems. Long-term bioassays, both fresh and salt water, are underway with indepth analytical chemistry to determine the magnitude of the chlorination by-product problem

  1. Sweet corn water productivity under several deficit irrigation regimes applied during vegetative growth stage using treated wastewater as water irrigation source

    DEFF Research Database (Denmark)

    Hirich, A.; Rami, A.; Laajaj, K.

    2012-01-01

    Yield and Crop Water Productivity are crucial issues in sustainable agriculture, especially in high-demand resource crops such as sweet corn. This study was conducted to investigate agronomic responses such as plant growth, yield and soil parameters (EC and Nitrate accumulation) to several deficit...

  2. Dobowe wahania deficytu wodnego i ich zależność od czynników klimatycznych [Diurnal changes of water saturation deficit in leaves and their dependence on the climatic factors

    Directory of Open Access Journals (Sweden)

    J. Czerski

    2015-01-01

    Full Text Available Daily changes in water suction deficit (WSD in different species of Nicotiana, Digitalis, Calendula, Beta and Brassica were studied. Significant water deficit in the middle of the day was demonstrated for all plants studied.

  3. Effects of water deficit on breadmaking quality and storage protein compositions in bread wheat (Triticum aestivum L.).

    Science.gov (United States)

    Zhou, Jiaxing; Liu, Dongmiao; Deng, Xiong; Zhen, Shoumin; Wang, Zhimin; Yan, Yueming

    2018-03-12

    Water deficiency affects grain proteome dynamics and storage protein compositions, resulting in changes in gluten viscoelasticity. In this study, the effects of field water deficit on wheat breadmaking quality and grain storage proteins were investigated. Water deficiency produced a shorter grain-filling period, a decrease in grain number, grain weight and grain yield, a reduced starch granule size and increased protein content and glutenin macropolymer contents, resulting in superior dough properties and breadmaking quality. Reverse phase ultra-performance liquid chromatography analysis showed that the total gliadin and glutenin content and the accumulation of individual components were significantly increased by water deficiency. Two-dimensional gel electrophoresis detected 144 individual storage protein spots with significant accumulation changes in developing grains under water deficit. Comparative proteomic analysis revealed that water deficiency resulted in significant upregulation of 12 gliadins, 12 high-molecular-weight glutenin subunits and 46 low-molecular-weight glutenin subunits. Quantitative real-time polymerase chain reaction analysis revealed that the expression of storage protein biosynthesis-related transcription factors Dof and Spa was upregulated by water deficiency. The present results illustrated that water deficiency leads to increased accumulation of storage protein components and upregulated expression of Dof and Spa, resulting in an improvement in glutenin strength and breadmaking quality. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  4. Impact of soda-lime borosilicate glass composition on water penetration and water structure at the first time of alteration

    International Nuclear Information System (INIS)

    Rebiscoul, D.; Bruguier, F.; Gin, S.; Magnin, V.

    2012-01-01

    In this study, the impact of soda-lime borosilicate glass composition and particularly the effect of charge compensators such Ca and Na and, of network formers such Si and Zr, on water penetration and water structure at the first time of alteration were investigated. Two non-destructive techniques were combined: the Fourier transform infrared spectroscopy in attenuated total reflection geometry to precise the predominant alteration mechanisms and assess the water structure in altered zone and the grazing incidence X-ray reflectometry to determine the thickness of the altered glass zone allowing to calculate the water diffusion coefficients through the glasses. The results of glass alteration at pH = 3 and 30 degrees C have shown that hydrolysis was the predominant mechanism after few seconds for glass having a high amount of non-binding oxygen. For the other glasses, which for the diffusion was the limiting reaction, the calculated water diffusion coefficients were comprised between 10 -21 and 10 -19 m 2 .s -1 and vary as a function of glass composition. An activation energy of 76.9 kJ.mol -1 was calculated and appears to be higher than inert gas diffusion through the glass highlighting that water molecules strongly interact with the glass matrix. (authors)

  5. Water deficit and salt stress diagnosis through LED induced chlorophyll fluorescence analysis in Jatropha curcas L. oil plants for biodiesel

    Science.gov (United States)

    Gouveia-Neto, Artur S.; Silva, Elias A., Jr.; Oliveira, Ronaldo A.; Cunha, Patrícia C.; Costa, Ernande B.; Câmara, Terezinha J. R.; Willadino, Lilia G.

    2011-02-01

    Light-emitting-diode induced chlorophyll fluorescence analysis is employed to investigate the effect of water and salt stress upon the growth process of physicnut(jatropha curcas) grain oil plants for biofuel. Red(Fr) and far-red (FFr) chlorophyll fluorescence emission signals around 685 nm and 735 nm, respectively, were observed and examined as a function of the stress intensity(salt concentration and water deficit) for a period of time of 30 days. The chlorophyll fluorescence(ChlF) ratio Fr/FFr which is a valuable nondestructive and nonintrusive indicator of the chlorophyll content of leaves was exploited to monitor the level of stress experienced by the jatropha plants. The ChlF technique data indicated that salinity plays a minor role in the chlorophyll concentration of leaves tissues for NaCl concentrations in the 25 to 200 mM range, and results agreed quite well with those obtained using conventional destructive spectrophotometric methods. Nevertheless, for higher NaCl concentrations a noticeable decrease in the Chl content was observed. The Chl fluorescence ratio analysis also permitted detection of damage caused by water deficit in the early stages of the plants growing process. A significant variation of the Fr/FFr ratio was observed sample in the first 10 days of the experiment when one compared control and nonwatered samples. The results suggest that the technique may potentially be applied as an early-warning indicator of stress caused by water deficit.

  6. Alterations in pain response are partially reversed by methylphenidate (Ritalin) in adults with attention deficit hyperactivity disorder (ADHD).

    Science.gov (United States)

    Treister, Roi; Eisenberg, Elon; Demeter, Naor; Pud, Dorit

    2015-01-01

    Attention deficit hyperactivity disorder (ADHD) is characterized by dysregulation of sensory processing and neurobiology of dopamine. Although cumulative evidence suggests that dopamine is involved in pain processing, pain perception in ADHD subjects and the effect of dopamine agonists such as methylphenidate (MP, Ritalin) on it have rarely been studied. The aims of this study were to (1) psychophysically assess sensitivity to pain in ADHD subjects as compared to controls and (2) examine the effects of MP on pain response in ADHD subjects. Thirty subjects with ADHD and 30 age- and gender-matched controls participated in a preliminary trial. Pain threshold, intensity, and tolerance in response to cold pain stimulation were measured for both groups (ADHD with no treatment). In addition, the ADHD group was reassessed following a single dose of MP treatment. The ADHD subjects "without MP" in comparison with controls displayed significantly shorter cold pain threshold (2.8 ± 2.1 vs. 5.8 ± 2.5 seconds, respectively, P ADHD subjects increased significantly compared to those with no treatment (3.6 ± 2.5 seconds, P = 0.011, and 46.4 ± 53.3 seconds, P ADHD are more sensitive to pain compared with controls and that MP may exert antinociceptive properties in these subjects. Randomized, controlled trials are warranted to verify these findings. © 2013 World Institute of Pain.

  7. Voluntary physical exercise alters attentional orienting and social behavior in a rat model of attention-deficit/hyperactivity disorder.

    Science.gov (United States)

    Hopkins, Michael E; Sharma, Mita; Evans, Gretchen C; Bucci, David J

    2009-06-01

    The effects of voluntary physical exercise on attentional function and social behavior were examined in male and female spontaneously hypertensive rats (SHR), a commonly used animal model of attention-deficit/hyperactivity disorder (ADHD). Rats in the exercise groups had free access to a running wheel for 2 weeks and then all rats received nonreinforced presentations of a visual stimulus (light) during the 1st training session, followed by daily sessions in which the light was paired with food. Nonexercising male and female SHR rats exhibited more unconditioned orienting behavior than Wistar-Kyoto rats. SHRs also exhibited impaired conditioning when the light was paired with food. Exercise reduced orienting in female SHRs but not in male SHRs. In the social interaction task, nonexercising male and female SHRs interacted more with an unfamiliar rat than Wistar-Kyoto rats. Exercise reduced the number of social interactions in female SHRs but not male SHRs. There were no differences in general locomotor activity observed between the nonexercising and exercising SHRs. These data indicate that exercise may preferentially benefit female SHRs, and has implications for using exercise as an intervention for ADHD and for understanding sex differences in the effects of exercise on behavior. Copyright (c) 2009 APA, all rights reserved.

  8. Neuroprotective potential of curcumin in combination with piperine against 6-hydroxy dopamine induced motor deficit and neurochemical alterations in rats.

    Science.gov (United States)

    Singh, Shamsher; Kumar, Puneet

    2017-02-01

    6-hydroxy dopamine (6-OHDA) is a neurotoxin which on intranigral administration produces severe nigrostriatal damage with motor and cognitive deficit in animals. Curcumin (CMN) in combination with bioenhancer piperine (PP) in 6-hydroxydopamine-induced Parkinsonian rats was used to investigate the antioxidant, neuromodulatory and neuroprotective mechanisms. Hemi-Parkinson's rat model was developed with intranigral infusion of 6-OHDA (8 μg/2 μl, once, unilaterally), treatment with CMN (25 and 50 mg/kg) and combination of PP (2.5 mg/kg) with CMN (25 mg/kg) was given daily for 21 days starting from the 7th day after 6-OHDA infusion. The behavioral (locomotor, grip strength, and narrow beam walk) parameters were studied on weekly basis. On 22nd day, isolated brain preparations were subjected to biochemical (lipid peroxidation, glutathione, and nitrite), neuroinflammatory (IL-1β, IL-6, and TNF- α), and neurochemical (DA, NE, 5- HT, GABA, Glutamate, DOPAC, HVA, and 5-HIAA) analysis. Oral administration of CMN had significantly prevented behavioral, neuroinflammatory, and neurochemical changes and preserved the antioxidant potential of the nigrostriatum in rats treated with 6-OHDA. In the present study, PP and CMN had afforded a better neuroprotective effect compared to alone treatment on behavior, biochemical, neuroinflammatory, and neurochemical parameters in rats.

  9. Appetite Suppression and Altered Food Preferences Coincide with Changes in Appetite-Mediating Hormones During Energy Deficit at High Altitude, But Are Not Affected by Protein Intake.

    Science.gov (United States)

    Karl, J Philip; Cole, Renee E; Berryman, Claire E; Finlayson, Graham; Radcliffe, Patrick N; Kominsky, Matthew T; Murphy, Nancy E; Carbone, John W; Rood, Jennifer C; Young, Andrew J; Pasiakos, Stefan M

    2018-02-12

    Karl, J. Philip, Renee E. Cole, Claire E. Berryman, Graham Finlayson, Patrick N. Radcliffe, Matthew T. Kominsky, Nancy E. Murphy, John W. Carbone, Jennifer C. Rood, Andrew J. Young, and Stefan M. Pasiakos. Appetite Suppression and Altered Food Preferences Coincide with Changes in Appetite-Mediating Hormones During Energy Deficit at High Altitude, But Are Not Affected by Protein Intake. High Alt Med Biol. 00:000-000, 2018.-Anorexia and unintentional body weight loss are common during high altitude (HA) sojourn, but underlying mechanisms are not fully characterized, and the impact of dietary macronutrient composition on appetite regulation at HA is unknown. This study aimed to determine the effects of a hypocaloric higher protein diet on perceived appetite and food preferences during HA sojourn and to examine longitudinal changes in perceived appetite, appetite mediating hormones, and food preferences during acclimatization and weight loss at HA. Following a 21-day level (SL) period, 17 unacclimatized males ascended to and resided at HA (4300 m) for 22 days. At HA, participants were randomized to consume measured standard-protein (1.0 g protein/kg/d) or higher protein (2.0 g/kg/d) hypocaloric diets (45% carbohydrate, 30% energy restriction) and engaged in prescribed physical activity to induce an estimated 40% energy deficit. Appetite, food preferences, and appetite-mediating hormones were measured at SL and at the beginning and end of HA. Diet composition had no effect on any outcome. Relative to SL, appetite was lower during acute HA (days 0 and 1), but not different after acclimatization and weight loss (HA day 18), and food preferences indicated an increased preference for sweet- and low-protein foods during acute HA, but for high-fat foods after acclimatization and weight loss. Insulin, leptin, and cholecystokinin concentrations were elevated during acute HA, but not after acclimatization and weight loss, whereas acylated ghrelin concentrations were

  10. Altered tryptophan and alanine transport in fibroblasts from boys with attention-deficit/hyperactivity disorder (ADHD: an in vitro study

    Directory of Open Access Journals (Sweden)

    Vumma Ravi

    2011-09-01

    Full Text Available Abstract Background The catecholaminergic and serotonergic neurotransmitter systems are implicated in the pathophysiology of attention-deficit/hyperactivity disorder (ADHD. The amino acid tyrosine is the precursor for synthesis of the catecholamines dopamine and norepinephrine, while tryptophan is the precursor of serotonin. A disturbed transport of tyrosine, as well as other amino acids, has been found in a number of other psychiatric disorders, such as schizophrenia, bipolar disorder and autism, when using the fibroblast cell model. Hence, the aim of this study was to explore whether children with ADHD may have disturbed amino acid transport. Methods Fibroblast cells were cultured from skin biopsies obtained from 14 boys diagnosed with ADHD and from 13 matching boys without a diagnosis of a developmental disorder. Transport of the amino acids tyrosine, tryptophan and alanine across the cell membrane was measured by the cluster tray method. The kinetic parameters, maximal transport capacity (Vmax and affinity constant (Km were determined. Any difference between the two groups was analyzed by Student's unpaired t-test or the Mann Whitney U test. Results The ADHD group had significantly decreased Vmax (p = 0.039 and Km (increased affinity (p = 0.010 of tryptophan transport in comparison to controls. They also had a significantly higher Vmaxof alanine transport (p = 0.031, but the Km of alanine transport did not differ significantly. There were no significant differences in any of the kinetic parameters regarding tyrosine transport in fibroblasts for the ADHD group. Conclusions Tryptophan uses the same transport systems in both fibroblasts and at the blood brain barrier (BBB. Hence, a decreased transport capacity of tryptophan implies that less tryptophan is being transported across the BBB in the ADHD group. This could lead to deficient serotonin access in the brain that might cause disturbances in both the serotonergic and the catecholaminergic

  11. WATER DEFICIT EFFECT ON YIELD AND FORAGE QUALITY OF MEDICAGO SATIVA POPULATIONS UNDER FIELD CONDITIONS IN MARRAKESH AREA (MOROCCO)

    OpenAIRE

    Mohamed FARISSI; Cherki GHOULAM; Abdelaziz BOUIZGAREN

    2014-01-01

    The present study focused the effect of water deficit on agronomic potential and some traits related to forage quality in plants of Moroccan Alfalfa (Medicago sativa L.) populations (Taf 1, Taf 2, Dem and Tata) originated from Oasis and High Atlas of Morocco and an introduced variety from Australia (Siriver). The experiment was conducted under field conditions in experimental station of INRA-Marrakech and under two irrigation treatments. The first treatment was normal irrigation, providing an...

  12. The Alteration of Emotion Regulation Precedes the Deficits in Interval Timing in the BACHD Rat Model for Huntington Disease

    Directory of Open Access Journals (Sweden)

    Daniel Garces

    2018-05-01

    Full Text Available Huntington disease (HD is an autosomal dominantly inherited, progressive neurodegenerative disorder which is accompanied by executive dysfunctions and emotional alteration. The aim of the present study was to assess the impact of emotion/stress on on-going highly demanding cognitive tasks, i.e., temporal processing, as a function of age in BACHD rats (a “full length” model of HD. Middle-aged (4–6 months and old (10–12 months rats were first trained on a 2 vs. 8-s temporal discrimination task, and then exposed to a series of bisection tests under normal and stressful (10 mild unpredictable foot-shocks conditions. The animals were then trained on a peak interval task, in which reinforced fixed-interval (FI 30-s trials were randomly intermixed with non-reinforced probe trials. After training, the effect of stress upon time perception was again assessed. Sensitivity to foot-shocks was also assessed independently. The results show effects of both age and genotype, with largely greater effects in old BACHD animals. The older BACHD animals had impaired learning in both tasks, but reached equivalent levels of performance as WT animals at the end of training in the temporal discrimination task, while remaining impaired in the peak interval task. Whereas sensitivity to foot-shock did not differ between BACHD and WT rats, delivery of foot-shocks during the test sessions had a disruptive impact on temporal behavior in WT animals, an effect which increased with age. In contrast, BACHD rats, independent of age, did not show any significant disruption under stress. In conclusion, BACHD rats showed a disruption in temporal learning in late symptomatic animals. Age-related modification in stress-induced impairment of temporal control of behavior was also observed, an effect which was greatly reduced in BACHD animals, thus confirming previous results suggesting reduced emotional reactivity in HD animals. The results suggest a staggered onset in cognitive

  13. Correlating lesion size and location to deficits after ischemic stroke: the influence of accounting for altered peri-necrotic tissue and incidental silent infarcts

    Directory of Open Access Journals (Sweden)

    Black Sandra E

    2010-01-01

    Full Text Available Abstract Background Investigators frequently quantify and evaluate the location and size of stroke lesions to help uncover cerebral anatomical correlates of deficits observed after first-ever stroke. However, it is common to discover silent infarcts such as lacunes in patients identified clinically as 'first-ever' stroke, and it is unclear if including these incidental findings may impact lesion-based investigations of brain-behaviour relationships. There is also debate concerning how to best define the boundaries of necrotic stroke lesions that blend in an ill-defined way into surrounding tissue, as it is unclear whether including this altered peri-necrotic tissue region may influence studies of brain-behaviour relationships. Therefore, for patients with clinically overt stroke, we examined whether including altered peri-necrotic tissue and incidental silent strokes influenced either lesion volume correlations with a measure of sensorimotor impairment or the anatomical localization of this impairment established using subtraction lesion analysis. Methods Chronic stroke lesions of 41 patients were manually traced from digital T1-MRI to sequentially include the: necrotic lesion core, altered peri-necrotic tissue, silent lesions in the same hemisphere as the index lesion, and silent lesions in the opposite hemisphere. Lesion volumes for each region were examined for correlation with motor impairment scores, and subtraction analysis was used to highlight anatomical lesion loci associated with this deficit. Results For subtraction lesion analysis, including peri-necrotic tissue resulted in a larger region of more frequent damage being seen in the basal ganglia. For correlational analysis, only the volume of the lesion core was significantly associated with motor impairment scores (r = -0.35, p = 0.025. In a sub-analysis of patients with small subcortical index lesions, adding silent lesions in the opposite hemisphere to the volume of the index

  14. Correlation between subacute sensorimotor deficits and brain water content after surgical brain injury in rats

    OpenAIRE

    McBride, Devin W.; Wang, Yuechun; Sherchan, Prativa; Tang, Jiping; Zhang, John H.

    2015-01-01

    Brain edema is a major contributor to poor outcome and reduced quality of life after surgical brain injury (SBI). Although SBI pathophysiology is well-known, the correlation between cerebral edema and neurological deficits has not been thoroughly examined in the rat model of SBI. Thus, the purpose of this study was to determine the correlation between brain edema and deficits in standard sensorimotor neurobehavior tests for rats subjected to SBI. Sixty male Sprague-Dawley rats were subjected ...

  15. Reorganization of Azospirillum brasilense cell membrane is mediated by lipid composition adjustment to maintain optimal fluidity during water deficit.

    Science.gov (United States)

    Cesari, A B; Paulucci, N S; Biasutti, M A; Reguera, Y B; Gallarato, L A; Kilmurray, C; Dardanelli, M S

    2016-01-01

    We study the Azospirillum brasilense tolerance to water deficit and the dynamics of adaptive process at the level of the membrane. Azospirillum brasilense was exposed to polyethylene glycol (PEG) growth and PEG shock. Tolerance, phospholipids and fatty acid (FA) composition and membrane fluidity were determined. Azospirillum brasilense was able to grow in the presence of PEG; however, its viability was reduced. Cells grown with PEG showed membrane fluidity similar to those grown without, the lipid composition was modified, increasing phosphatidylcholine and decreasing phosphatidylethanolamine amounts. The unsaturation FAs degree was reduced. The dynamics of the adaptive response revealed a decrease in fluidity 20 min after the addition of PEG, indicating that the PEG has a fluidizing effect on the hydrophobic region of the cell membrane. Fluidity returned to initial values after 60 min of PEG exposure. Azospirillum brasilense is able to perceive osmotic changes by changing the membrane fluidity. This effect is offset by changes in the composition of membrane phospholipid and FA, contributing to the homeostasis of membrane fluidity under water deficit. This knowledge can be used to develop new Azospirillum brasilense formulations showing an adapted membrane to water deficit. © 2015 The Society for Applied Microbiology.

  16. Evaluating effect of biofertilizer on nodulation and soybean (Glycine max L plants growth characteristics under water deficit stress of seed

    Directory of Open Access Journals (Sweden)

    M. Tajik Khaveh

    2016-05-01

    Full Text Available In order to evaluate the effects of biofertilizer on soybean (Glycine max L. seed vigor that produced under water deficit condition and related traits, an experiment was conducted in a factorial layout based of complete randomized block design with four replications at the research greenhouse of Aboureihan campus- Tehran University, Iran. Experimental treatments were include biofertilizer (seed inoculation with Bradyrhizobium japonicum, co-inoculation with Bradyrhizobium japonicum and Pseudomonas fluorescens, co-inoculation with Bradyrhizobium japonicum and Glomus mosseae, Cultivar (Zalta Zalha and Clark×Hobbit line and water deficit stress [irrigation plants after 50 (normal irrigation, 100 (medium stress, 150 (sever stress mm evaporation from pan class A, in parents field]. Results showed that the water deficit stress had negative effects on seed quality and seedling emergence percentage, mean daily seedling emergence, root, leaf and shoot dry weight, number of nodule were decreased. ZaltaZalha cultivar had higher shoot dry weight and number of leaf compared with other cultivars. Applications of biofertilzer was effective on stem diameter, root, leaf and shoot dry weight, number of leaf and nodule and those attributes increased by co-inoculation of Bradyrhizobium japonicum and Glomus mosseae. Also, use of biofertilizer in stress levels was effective on stem dry weight. Stem dry weight was increased by Co-inoculation of cultivar seeds with Bradyrhizobium japonicum and Glomus mosseae.

  17. Genes responding to water deficit in apple (Malus × domestica Borkh.) roots.

    Science.gov (United States)

    Bassett, Carole Leavel; Baldo, Angela M; Moore, Jacob T; Jenkins, Ryan M; Soffe, Doug S; Wisniewski, Michael E; Norelli, John L; Farrell, Robert E

    2014-07-08

    Individual plants adapt to their immediate environment using a combination of biochemical, morphological and life cycle strategies. Because woody plants are long-lived perennials, they cannot rely on annual life cycle strategies alone to survive abiotic stresses. In this study we used suppression subtractive hybridization to identify genes both up- and down-regulated in roots during water deficit treatment and recovery. In addition we followed the expression of select genes in the roots, leaves, bark and xylem of 'Royal Gala' apple subjected to a simulated drought and subsequent recovery. In agreement with studies from both herbaceous and woody plants, a number of common drought-responsive genes were identified, as well as a few not previously reported. Three genes were selected for more in depth analysis: a high affinity nitrate transporter (MdNRT2.4), a mitochondrial outer membrane translocase (MdTOM7.1), and a gene encoding an NPR1 homolog (MpNPR1-2). Quantitative expression of these genes in apple roots, bark and leaves was consistent with their roles in nutrition and defense. Additional genes from apple roots responding to drought were identified using suppression subtraction hybridization compared to a previous EST analysis from the same organ. Genes up- and down-regulated during drought recovery in roots were also identified. Elevated levels of a high affinity nitrate transporter were found in roots suggesting that nitrogen uptake shifted from low affinity transport due to the predicted reduction in nitrate concentration in drought-treated roots. Suppression of a NPR1 gene in leaves of drought-treated apple trees may explain in part the increased disease susceptibility of trees subjected to dehydrative conditions.

  18. Alteration of borosilicate glass under water saturated condition

    International Nuclear Information System (INIS)

    Tsukimura, K.; Matsuhisa, Y.; Kanai, Y.; Hirai, H.

    1991-01-01

    In the long term of the high-level nuclear waste disposal, the dissolving rates of radionuclides from the waste will be controlled by crystalline phases secondarily formed in the borosilicate glass by reaction with ground water. We have determined the crystalline phases formed from borosilicate glass in a hydrothermal experiment. Borosilicate glass powder (50 mg, Si 40 B 20 Al 4 Li 12 Na 14 K 3 Ca 2 Fe 5 O 140 ) and 200 ml of water were reacted at 300degC and 300 bars for 2 weeks with a cold-seal type hydrothermal high pressure apparatus. After the reaction the liquid phase was analyzed with atomic absorption spectroscopy and the solid phases with x-ray powder diffraction and analytical electron microscopy. The liquid phase contains 58 % of Na, 14 % of Li and 11 % of K but less than 1 % of Ca and Fe. The solid phases were found to be zeolite and smectite. The zeolite is isostructural with analcime Na 2 Al 2 (SiO 3 ) 4 · 2H 2 O or wairakite CaAl 2 (SiO 3 ) 4 · 2H 2 O and contains Ca and Si as major constituents but does not contain Al. Although no direct analytical evidence is available, logical induction of the experimental results indicates that the chemical composition of the zeolite is CaB 2 (SiO 3 ) 4 . The remaining x-ray powder diffraction peaks are same as those of smectite Na 06.7 (Al 3.33 Mg 0.67 )Si 8 O 20 (OH) 4 . However, since our starting material was free of Mg, and Na was not detected by AEM, the smectite may contain Fe instead of Mg, and Li instead of Na. (author)

  19. Warmed Winter Water Temperatures Alter Reproduction in Two Fish Species.

    Science.gov (United States)

    Firkus, Tyler; Rahel, Frank J; Bergman, Harold L; Cherrington, Brian D

    2018-02-01

    We examined the spawning success of Fathead Minnows (Pimephales promelas) and Johnny Darters (Etheostoma nigrum) exposed to elevated winter water temperatures typical of streams characterized by anthropogenic thermal inputs. When Fathead Minnows were exposed to temperature treatments of 12, 16, or 20 °C during the winter, spawning occurred at 16 and 20 °C but not 12 °C. Eggs were deposited over 9 weeks before winter spawning ceased. Fathead Minnows from the three winter temperature treatments were then exposed to a simulated spring transition. Spawning occurred at all three temperature treatments during the spring, but fish from the 16° and 20 °C treatment had delayed egg production indicating a latent effect of warm winter temperatures on spring spawning. mRNA analysis of the egg yolk protein vitellogenin showed elevated expression in female Fathead Minnows at 16 and 20 °C during winter spawning that decreased after winter spawning ceased, whereas Fathead Minnows at 12 °C maintained comparatively low expression during winter. Johnny Darters were exposed to 4 °C to represent winter temperatures in the absence of thermal inputs, and 12, 16, and 20 °C to represent varying degrees of winter thermal pollution. Johnny Darters spawned during winter at 12, 16, and 20 °C but not at 4 °C. Johnny Darters at 4 °C subsequently spawned following a simulated spring period while those at 12, 16, and 20 °C did not. Our results indicate elevated winter water temperatures common in effluent-dominated streams can promote out-of-season spawning and that vitellogenin expression is a useful indicator of spawning readiness for fish exposed to elevated winter temperatures.

  20. Warmed Winter Water Temperatures Alter Reproduction in Two Fish Species

    Science.gov (United States)

    Firkus, Tyler; Rahel, Frank J.; Bergman, Harold L.; Cherrington, Brian D.

    2018-02-01

    We examined the spawning success of Fathead Minnows ( Pimephales promelas) and Johnny Darters ( Etheostoma nigrum) exposed to elevated winter water temperatures typical of streams characterized by anthropogenic thermal inputs. When Fathead Minnows were exposed to temperature treatments of 12, 16, or 20 °C during the winter, spawning occurred at 16 and 20 °C but not 12 °C. Eggs were deposited over 9 weeks before winter spawning ceased. Fathead Minnows from the three winter temperature treatments were then exposed to a simulated spring transition. Spawning occurred at all three temperature treatments during the spring, but fish from the 16° and 20 °C treatment had delayed egg production indicating a latent effect of warm winter temperatures on spring spawning. mRNA analysis of the egg yolk protein vitellogenin showed elevated expression in female Fathead Minnows at 16 and 20 °C during winter spawning that decreased after winter spawning ceased, whereas Fathead Minnows at 12 °C maintained comparatively low expression during winter. Johnny Darters were exposed to 4 °C to represent winter temperatures in the absence of thermal inputs, and 12, 16, and 20 °C to represent varying degrees of winter thermal pollution. Johnny Darters spawned during winter at 12, 16, and 20 °C but not at 4 °C. Johnny Darters at 4 °C subsequently spawned following a simulated spring period while those at 12, 16, and 20 °C did not. Our results indicate elevated winter water temperatures common in effluent-dominated streams can promote out-of-season spawning and that vitellogenin expression is a useful indicator of spawning readiness for fish exposed to elevated winter temperatures.

  1. Adjustment of the dynamic weight distribution as a sensitive parameter for diagnosis of postural alteration in a rodent model of vestibular deficit.

    Directory of Open Access Journals (Sweden)

    Brahim Tighilet

    Full Text Available Vestibular disorders, by inducing significant posturo-locomotor and cognitive disorders, can significantly impair the most basic tasks of everyday life. Their precise diagnosis is essential to implement appropriate therapeutic countermeasures. Monitoring their evolution is also very important to validate or, on the contrary, to adapt the undertaken therapeutic actions. To date, the diagnosis methods of posturo-locomotor impairments are restricted to examinations that most often lack sensitivity and precision. In the present work we studied the alterations of the dynamic weight distribution in a rodent model of sudden and complete unilateral vestibular loss. We used a system of force sensors connected to a data analysis system to quantify in real time and in an automated way the weight bearing of the animal on the ground. We show here that sudden, unilateral, complete and permanent loss of the vestibular inputs causes a severe alteration of the dynamic ground weight distribution of vestibulo lesioned rodents. Characteristics of alterations in the dynamic weight distribution vary over time and follow the sequence of appearance and disappearance of the various symptoms that compose the vestibular syndrome. This study reveals for the first time that dynamic weight bearing is a very sensitive parameter for evaluating posturo-locomotor function impairment. Associated with more classical vestibular examinations, this paradigm can considerably enrich the methods for assessing and monitoring vestibular disorders. Systematic application of this type of evaluation to the dizzy or unstable patient could improve the detection of vestibular deficits and allow predicting better their impact on posture and walk. Thus it could also allow a better follow-up of the therapeutic approaches for rehabilitating gait and balance.

  2. Adjustment of the dynamic weight distribution as a sensitive parameter for diagnosis of postural alteration in a rodent model of vestibular deficit.

    Science.gov (United States)

    Tighilet, Brahim; Péricat, David; Frelat, Alais; Cazals, Yves; Rastoldo, Guillaume; Boyer, Florent; Dumas, Olivier; Chabbert, Christian

    2017-01-01

    Vestibular disorders, by inducing significant posturo-locomotor and cognitive disorders, can significantly impair the most basic tasks of everyday life. Their precise diagnosis is essential to implement appropriate therapeutic countermeasures. Monitoring their evolution is also very important to validate or, on the contrary, to adapt the undertaken therapeutic actions. To date, the diagnosis methods of posturo-locomotor impairments are restricted to examinations that most often lack sensitivity and precision. In the present work we studied the alterations of the dynamic weight distribution in a rodent model of sudden and complete unilateral vestibular loss. We used a system of force sensors connected to a data analysis system to quantify in real time and in an automated way the weight bearing of the animal on the ground. We show here that sudden, unilateral, complete and permanent loss of the vestibular inputs causes a severe alteration of the dynamic ground weight distribution of vestibulo lesioned rodents. Characteristics of alterations in the dynamic weight distribution vary over time and follow the sequence of appearance and disappearance of the various symptoms that compose the vestibular syndrome. This study reveals for the first time that dynamic weight bearing is a very sensitive parameter for evaluating posturo-locomotor function impairment. Associated with more classical vestibular examinations, this paradigm can considerably enrich the methods for assessing and monitoring vestibular disorders. Systematic application of this type of evaluation to the dizzy or unstable patient could improve the detection of vestibular deficits and allow predicting better their impact on posture and walk. Thus it could also allow a better follow-up of the therapeutic approaches for rehabilitating gait and balance.

  3. Three cycles of water deficit from seed to young plants of Moringa oleifera woody species improves stress tolerance.

    Science.gov (United States)

    Rivas, Rebeca; Oliveira, Marciel T; Santos, Mauro G

    2013-02-01

    The main objective of this study was to assess whether recurring water stress occurring from seed germination to young plants of Moringa oleifera Lam. are able to mitigate the drought stress effects. Germination, gas exchange and biochemical parameters were analysed after three cycles of water deficit. Young plants were used 50 days after germination under three osmotic potentials (0.0, -0.3 and -0.4 MPa). For each germination treatment, control (irrigated) and stressed (10% of water control) plants were compared for a total of six treatments. There were two cycles of drought interspersed with 10 days of rehydration. The young plants of M. oleifera showed increased tolerance to repeated cycles of drought, maintaining high relative water content (RWC), high water use efficiency (WUE), increased photosynthetic pigments and increased activity of antioxidant enzymes. There was rapid recovery of the photosynthetic rate during the rehydration period. The stressed plants from the -0.3 and -0.4 MPa treatments showed higher tolerance compared to the control plants. The results suggest that seeds of M. oleifera subjected to mild water deficit have had increased the ability for drought tolerance when young plant. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  4. The Impact of Precipitation Deficit and Urbanization on Variations in Water Storage in the Beijing-Tianjin-Hebei Urban Agglomeration

    Directory of Open Access Journals (Sweden)

    Zheng Chen

    2017-12-01

    Full Text Available Depletion of water resources has threatened water security in the Beijing-Tianjin-Hebei urban agglomeration, China. However, the relative importance of precipitation and urbanization to water storage change has not been sufficiently studied. In this study, both terrestrial water storage (TWS and groundwater storage (GWS change in Jing-Jin-Ji from 1979 to the 2010s were investigated, based on the global land data assimilation system (GLDAS and the EartH2Observe (E2O outputs, and we used a night light index as an index of urbanization. The results showed that TWS anomaly varied in three stages: significant increase from 1981 to 1996, rapid decrease from 1996 to 2002 and increase from 2002 to the 2010s. Simultaneously, GWS has decreased with about 41.5 cm (500% of GWS in 1979. Both urbanization and precipitation change influenced urban water resource variability. Urbanization was a relatively important factor to the depletion of TWS (explains 83% and GWS (explains 94% since the 1980s and the precipitation deficit explains 72% and 64% of TWS and GWS variabilities. It indicates that urbanization coupled with precipitation deficit has been a more important factor that impacted depletion of both TWS and GWS than climate change only, in the Jing-Jin-Ji region. Moreover, we suggested that the cumulative effect should be considered when discussing the relationship between influence factors and water storage change.

  5. Study of Sesame (Sesame indicum L. Cultivars based on Morphological Characteristics Under Water Deficit Stress Condition Using Factor Analysis

    Directory of Open Access Journals (Sweden)

    A Asghari

    2014-03-01

    Full Text Available In order to evaluation sesame cultivars based on morphological characteristics under water deficit stress condition using factor analysis, an experiment was conducted as a split plot based on randomized complete block design with three replications during 2009 in Research Center of Agriculture and Natural Resources in Parsabad. In this experiment, irrigation as the main factor at three levels (50, 75 and 100 percent of crop water requirement and ten sesame cultivars as the sub-factor were studied. The water requirement of sesame was calculated using CROPWAT software (Penman-Monteith method according to FAO-56. Results showed significant differences between the cultivars and the irrigation levels for all studied traits. Interaction between cultivars and irrigation levels was significant for some of traits. Comparisons of means showed that in water deficit condition, yield and all of traits reduced. In all traits the greatest amounts observed in complete irrigation treatment. In 50 percent of water requirement treatment, amount of leaf chlorophyll, root length, root branches and root length/plant height ratio were greater than other treatments. The Karaj1, Ultan, Naze and IS cultivars were better than other cultivars in stress and non stress condition. In factor analysis 5 and 4 first factors in non stress and stress condition explained 91.36 and 89.52 percent of trait variance, respectively. Grouping of sesame cultivars based on first and second factors in non stress conditions showed that Karaj1, Ultan and Naze cultivars were better than other cultivars. Also, in stress conditions Karaj1 and Ultan cultivars grouped as water deficit stress and better cultivars.

  6. Seasonal scale water deficit forecasting in Africa and the Middle East using NASA's Land Information System (LIS)

    Science.gov (United States)

    Peters-Lidard, C. D.; Arsenault, K. R.; Shukla, S.; Getirana, A.; McNally, A.; Koster, R. D.; Zaitchik, B. F.; Badr, H. S.; Roningen, J. M.; Kumar, S.; Funk, C. C.

    2017-12-01

    A seamless and effective water deficit monitoring and early warning system is critical for assessing food security in Africa and the Middle East. In this presentation, we report on the ongoing development and validation of a seasonal scale water deficit forecasting system based on NASA's Land Information System (LIS) and seasonal climate forecasts. First, our presentation will focus on the implementation and validation of drought and water availability monitoring products in the region. Next, it will focus on evaluating drought and water availability forecasts. Finally, details will be provided of our ongoing collaboration with end-user partners in the region (e.g., USAID's Famine Early Warning Systems Network, FEWS NET), on formulating meaningful early warning indicators, effective communication and seamless dissemination of the products through NASA's web-services. The water deficit forecasting system thus far incorporates NASA GMAO's Catchment and the Noah Multi-Physics (MP) LSMs. In addition, the LSMs' surface and subsurface runoff are routed through the Hydrological Modeling and Analysis Platform (HyMAP) to simulate surface water dynamics. To establish a climatology from 1981-2015, the two LSMs are driven by NASA/GMAO's Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2), and the USGS and UCSB Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) daily rainfall dataset. Comparison of the models' energy and hydrological budgets with independent observations suggests that major droughts are well-reflected in the climatology. The system uses seasonal climate forecasts from NASA's GEOS-5 (the Goddard Earth Observing System Model-5) and NCEP's Climate Forecast System-2, and it produces forecasts of soil moisture, ET and streamflow out to 6 months in the future. Forecasts of those variables are formulated in terms of indicators to provide forecasts of drought and water availability in the region. Current work suggests

  7. Effects of environmental enrichment on behavioral deficits and alterations in hippocampal BDNF induced by prenatal exposure to morphine in juvenile rats.

    Science.gov (United States)

    Ahmadalipour, A; Sadeghzadeh, J; Vafaei, A A; Bandegi, A R; Mohammadkhani, R; Rashidy-Pour, A

    2015-10-01

    Prenatal morphine exposure throughout pregnancy can induce a series of neurobehavioral and neurochemical disturbances by affecting central nervous system development. This study was designed to investigate the effects of an enriched environment on behavioral deficits and changes in hippocampal brain-derived neurotrophic factor (BDNF) levels induced by prenatal morphine in rats. On pregnancy days 11-18, female Wistar rats were randomly injected twice daily with saline or morphine. Offspring were weaned on postnatal day (PND) 21. They were subjected to a standard rearing environment or an enriched environment on PNDs 22-50. On PNDs 51-57, the behavioral responses including anxiety and depression-like behaviors, and passive avoidance memory as well as hippocampal BDNF levels were investigated. The light/dark (L/D) box and elevated plus maze (EPM) were used for the study of anxiety, forced swimming test (FST) was used to assess depression-like behavior and passive avoidance task was used to evaluate learning and memory. Prenatal morphine exposure caused a reduction in time spent in the EPM open arms and a reduction in time spent in the lit side of the L/D box. It also decreased step-through latency and increased time spent in the dark side of passive avoidance task. Prenatal morphine exposure also reduced immobility time and increased swimming time in FST. Postnatal rearing in an enriched environment counteracted with behavioral deficits in the EPM and passive avoidance task, but not in the L/D box. This suggests that exposure to an enriched environment during adolescence period alters anxiety profile in a task-specific manner. Prenatal morphine exposure reduced hippocampal BDNF levels, but enriched environment significantly increased BDNF levels in both saline- and morphine-exposed groups. Our results demonstrate that exposure to an enriched environment alleviates behavioral deficits induced by prenatal morphine exposure and up-regulates the decreased levels of BDNF

  8. Interactive response of photosynthetic characteristics in Haloxylon ammodendron and Hedysarum scoparium exposed to soil water and air vapor pressure deficits.

    Science.gov (United States)

    Gong, Chunmei; Wang, Jiajia; Hu, Congxia; Wang, Junhui; Ning, Pengbo; Bai, Juan

    2015-08-01

    C4 plants possess better drought tolerance than C3 plants. However, Hedysarum scoparium, a C3 species, is dominant and widely distributed in the desert areas of northwestern China due to its strong drought tolerance. This study compared it with Haloxylon ammodendron, a C4 species, regarding the interactive effects of drought stress and different leaf-air vapor pressure deficits. Variables of interest included gas exchange, the activity levels of key C4 photosynthetic enzymes, and cellular anatomy. In both species, gas exchange parameters were more sensitive to high vapor pressure deficit than to strong water stress, and the net CO2 assimilation rate (An) was enhanced as vapor pressure deficits increased. A close relationship between An and stomatal conductance (gs) suggested that the species shared a similar response mechanism. In H. ammodendron, the activity levels of key C4 enzymes were higher, including those of phosphoenolpyruvate carboxylase (PEPC) and nicotinamide adenine dinucleotide phosphate-malate enzyme (NADP-ME), whereas in H. scoparium, the activity level of nicotinamide adenine dinucleotide-malate enzyme (NAD-ME) was higher. Meanwhile, H. scoparium utilized adaptive structural features, including a larger relative vessel area and a shorter distance from vein to stomata, which facilitated the movement of water. These findings implied that some C4 biochemical pathways were present in H. scoparium to respond to environmental challenges. Copyright © 2015. Published by Elsevier B.V.

  9. Effects of deficit drip-irrigation scheduling regimes with saline water on pepper yield, water productivity and soil salinity under arid conditions of Tunisia

    Directory of Open Access Journals (Sweden)

    Kamel Nagaz

    2012-12-01

    Full Text Available A two-year study was carried out in order to assess the effects of different irrigation scheduling regimes with saline water on soil salinity, yield and water productivity of pepper under actual commercial-farming conditions in the arid region of Tunisia. Pepper was grown on a sandy soil and drip-irrigated with water having an ECi of 3.6 dS/m. Irrigation treatments consisted in water replacements of accumulated ETc at levels of 100% (FI, full irrigation, 80% (DI-80, 60% (DI-60, when the readily available water in the control treatment (FI is depleted, deficit irrigation during ripening stage (FI-MDI60 and farmer method corresponding to irrigation practices implemented by the local farmers (FM. Results on pepper yield and soil salinity are globally consistent between the two-year experiments and shows significant difference between irrigation regimes. Higher soil salinity was maintained over the two seasons, 2008 and 2009, with DI-60 and FM treatments than FI. FI-MDI60 and DI-80 treatments resulted also in low ECe values. Highest yields for both years were obtained under FI (22.3 and 24.4 t/ha although we didn’t find significant differences with the regulated deficit irrigation treatment (FI-DI60. However, the DI-80 and DI-60 treatments caused significant reductions in pepper yields through a reduction in fruits number/m² and average fruit weight in comparison with FI treatment. The FM increased soil salinity and caused significant reductions in yield with 14 to 43%, 12 to 39% more irrigation water use than FI, FI-MDI60 and DI-80 treatments, respectively, in 2008 and 2009. Yields for all irrigation treatments were higher in the second year compared to the first year. Water productivity (WP values reflected this difference and varied between 2.31 and 5.49 kg/m3. The WP was found to vary significantly among treatments, where the highest and the lowest values were observed for DI-60 treatment and FM, respectively. FI treatment provides

  10. Changes in activities of both photosystems and the regulatory effect of cyclic electron flow in field-grown cotton (Gossypium hirsutum L) under water deficit.

    Science.gov (United States)

    Yi, Xiao-Ping; Zhang, Ya-Li; Yao, He-Sheng; Han, Ji-Mei; Chow, Wah Soon; Fan, Da-Yong; Zhang, Wang-Feng

    2018-01-01

    To clarify the influence of water deficit on the functionality of the photosynthetic apparatus of cotton plants, leaf gas exchange, chlorophyll a fluorescence, and P700 redox state were examined in field-grown cotton Gossypium hirsutum L. cv. Xinluzao 45. In addition, we measured changes in the P515 signal and analyzed the activity of ATP synthase and the trans-thylakoid proton gradient (ΔpH). With increasing water deficit, the net CO 2 assimilation rate (A N ) and stomatal conductance (g s ) significantly decreased, but the maximum quantum efficiency of PSII photochemistry (F v /F m ) did not change. The photochemical activity of photosystem II (PSII) was reflected by the photochemical quenching coefficient (qP), quantum efficiency of photosystem II [Y(II)], and electron transport rate through PSII [ETR(II)], while the activity of photosystem I (PSI) was reflected by the quantum efficiency of photosystem I [Y(I)] and the electron transport rate through PSI [ETR(I)]. Both activities were maintained under mild water deficit, but were slightly decreased under moderate water deficit. Under moderate water deficit, cyclic electron flow (CEF), the fraction of absorbed light dissipated thermally via the ΔpH- and xanthophyll-regulated process [Y(NPQ)], and the fraction of P700 oxidized under a given set of conditions [Y(ND)] increased. Our results suggest that the activities of both photosystems are stable under mild water deficit and decrease only slightly under moderate water deficit. Moderate water deficit stimulates CEF, and the stimulation of CEF is essential for protecting PSI and PSII against photoinhibition. Copyright © 2017 Elsevier GmbH. All rights reserved.

  11. Variation in total sugars and reductive sugars in the moss Pleurozium schreberi (hylocomiaceae) under water deficit conditions

    International Nuclear Information System (INIS)

    Montenegro Ruiz, Luis Carlos; Melgarejo Munoz, Luz Marina.

    2012-01-01

    The structural simplicity of the bryophytes exposed them easily to water stress, forcing them to have physiological and biochemical mechanisms that enable them to survive. This study evaluated the variation of total soluble sugars and reducing sugars in relation to relative water content, in Pleurozium schreberi when faced with low water content in the Paramo de Chingaza (Colombia) and under simulated conditions of water deficit in the laboratory. we found that total sugars increase when the plant is dehydrated and returned to their normal content when re-hydrated moss, this could be interpreted as a possible mechanism of osmotic adjustment and osmoprotection of the cell content and cellular structure. Reducing sugars showed no significant variation, showing that monosaccharides do not have a protective role during dehydration.

  12. Perturabation of nodular operation under salt and water deficit stress in rhizobium common bean symbiosis

    International Nuclear Information System (INIS)

    Harzalli Jebara, Salwa

    2006-01-01

    This work aims at the search for markers of tolerance to the osmotic stress and nodular efficiency of symbiosis Haricot Rhizobium. Thus, after having fixed the best period of hydroponic culture, we showed that a severe salt treatment generated an inhibition of the parameters of growth and nodulation. These inhibitions are accompanied by an inhibition of the enzymatic activities: ascorbate peroxidase (APX) and catalase (CAT), but an activation of peroxidase (POX) and superoxide dismutase (SOD), suggesting that these two antioxydants can be biochemical markers of the tolerance to salinity. To check the validity of these markers and to see the participation of the vegetable genotype in the response to the stress, we compared the effect of two concentrations salt 25 and 50 mM NaCe at two contrasting genotypes BAT477 tolerant and sensitive COCOT. This study illustrates the role of the vegetable genotype in the tolerance and efficiency and emphasize a significant result that SOD and POX constitute biochemical markers of tolerance to salinity. In order to ensure itself of the validity of this assumption in the event of water deficit stress, a treatment of 50 mM mannitol is applied to 16 symbioses formed by four genotypes of bean BAT477, COCOT, Flamingo and BRB17 inoculated by four strains of rhizobium CIAT899, 12 to 3, 1 to 6 and 8 to 3. This study permits us to make a screening of these symbioses according to their efficiency and their tolerance based on parameters of growth, of fixing and extent of the antioxydant enzymatic activities. It gets clear that the response of enzymatic antioxydants is in relation to the intrinsic potentialities of the partners of symbioses and appears to act as of the first stages of recognition plants bacterium. It will be retained that activities POX and SOD are markers of nodular tolerance. The CAT is the enzyme most connected to each partner of symbiosis and the APX would play a rather functional role. The heterogeneity of found answer

  13. Drought effect on growth, gas exchange and yield, in two strains of local barley Ardhaoui, under water deficit conditions in southern Tunisia.

    Science.gov (United States)

    Thameur, Afwa; Lachiheb, Belgacem; Ferchichi, Ali

    2012-12-30

    Two local barley strains cv. Ardhaoui originated from Tlalit and Switir, sourthern Tunisia were grown in pots in a glasshouse assay, under well-watered conditions for a month. Plants were then either subjected to water deficit (treatment) or continually well-watered (control). Control pots were irrigated several times each week to maintain soil moisture near field capacity (FC), while stress pots experienced soil drying by withholding irrigation until they reached 50% of FC. Variation in relative water content, leaf area, leaf appearance rate and leaf gas exchange (i.e. net CO(2) assimilation rate (A), transpiration (E), and stomatal conductance (gs)) in response to water deficit was investigated. High leaf relative water content (RWC) was maintained in Tlalit by stomatal closure and a reduction of leaf area. Reduction in leaf area was due to decline in leaf gas exchange during water deficit. Tlalit was found to be drought tolerant and able to maintain higher leaf RWC under drought conditions. Water deficit treatment reduced stomatal conductance by 43% at anthesis. High net CO(2) assimilation rate under water deficit was associated with high RWC (r = 0.998; P gas exchange parameters were found, which can give some indications on the degree of drought tolerance. Thus, the ability of the low leaf area plants to maintain higher RWC could explain the differences in drought tolerance in studied barley strains. Results showed that Tlalit showed to be more efficient and more productive than Switir. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Treadmill running prevents age-related memory deficit and alters neurotrophic factors and oxidative damage in the hippocampus of Wistar rats.

    Science.gov (United States)

    Vanzella, Cláudia; Neves, Juliana Dalibor; Vizuete, Adriana Fernanda; Aristimunha, Dirceu; Kolling, Janaína; Longoni, Aline; Gonçalves, Carlos Alberto Saraiva; Wyse, Angela T S; Netto, Carlos Alexandre

    2017-09-15

    Clinical and pre-clinical studies indicate that exercise is beneficial to many aspects of brain function especially during aging. The present study investigated the effects of a treadmill running protocol in young (3month-old) and aged (22month-old) male Wistar rats, on: I) cognitive function, as assessed by spatial reference memory in the Morris water maze; II) oxidative stress parameters and the expression of neurotrophic factors BDNF, NT-3, IGF-1 and VEGF in the hippocampus. Animals of both ages were assigned to sedentary (non-exercised) and exercised (20min of daily running sessions, 3 times per week for 4weeks) groups. Cognition was assessed by a reference memory task run in the Morris water maze; twenty four hours after last session of behavioral testing hippocampi were collected for biochemical analysis. Results demonstrate that the moderate treadmill running exercise: I) prevented age-related deficits in reference memory in the Morris water maze; II) prevented the age-related increase of reactive oxygen species levels and lipid peroxidation in the hippocampus; III) caused an increase of BDNF, NT-3 and IGF-1 expression in the hippocampus of aged rats. Taken together, results suggest that both exercise molecular effects, namely the reduction of oxidative stress and the increase of neurotrophic factors expression in the hippocampus, might be related to its positive effect on memory performance in aged rats. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Increased protein content of chickpea (Cicer arietinum L.) inoculated with arbuscular mycorrhizal fungi and nitrogen-fixing bacteria under water deficit conditions.

    Science.gov (United States)

    Oliveira, Rui S; Carvalho, Patrícia; Marques, Guilhermina; Ferreira, Luís; Nunes, Mafalda; Rocha, Inês; Ma, Ying; Carvalho, Maria F; Vosátka, Miroslav; Freitas, Helena

    2017-10-01

    Chickpea (Cicer arietinum L.) is a widely cropped pulse and an important source of proteins for humans. In Mediterranean regions it is predicted that drought will reduce soil moisture and become a major issue in agricultural practice. Nitrogen (N)-fixing bacteria and arbuscular mycorrhizal (AM) fungi have the potential to improve plant growth and drought tolerance. The aim of the study was to assess the effects of N-fixing bacteria and AM fungi on the growth, grain yield and protein content of chickpea under water deficit. Plants inoculated with Mesorhizobium mediterraneum or Rhizophagus irregularis without water deficit and inoculated with M. mediterraneum under moderate water deficit had significant increases in biomass. Inoculation with microbial symbionts brought no benefits to chickpea under severe water deficit. However, under moderate water deficit grain crude protein was increased by 13%, 17% and 22% in plants inoculated with M. mediterraneum, R. irregularis and M. mediterraneum + R. irregularis, respectively. Inoculation with N-fixing bacteria and AM fungi has the potential to benefit agricultural production of chickpea under water deficit conditions and to contribute to increased grain protein content. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  16. Effects of water deficit and nitrogen levels on grain yield and oil and protein contents of maize

    Directory of Open Access Journals (Sweden)

    Kazem Ghassemi-Golezani

    2015-02-01

    Full Text Available This research was conducted in 2014, to evaluate the effects of water deficit and nitrogen fertilizer on grain yield, oil and protein contents of maize (cv. double Cross 303. The experiment was arranged as split-plot based on Randomized Complete Block design (RCB with three replications. Irrigation treatments (irrigation after 60, 90, 120 and 150 mm evaporation and nitrogen levels (0, 46 and 92 kg N/ha were located in the main and sub plots, respectively. Mean grain yield per unit area decreased with decreasing water availability, but it was improved with increasing nitrogen fertilizer. Grain oil percentage significantly decreased, but protein percentage slightly increased as a result of water deficit. In general, oil and protein yields significantly decreased under moderate and severe water stress, mainly because of decreasing grain yield under these conditions. Nitrogen application decreased oil percentage, but increased protein percentage significantly. Nevertheless, nitrogen fertilizer enhanced oil and protein yields per unit area, with no significant difference between nitrogen rates. These results were positively related with grain yield per unit area in maize.

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

    Science.gov (United States)

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

    2017-12-01

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

  18. Beta-hydroxy-beta-methylbutyrate (HMB) ameliorates age-related deficits in water maze performance, especially in male rats.

    Science.gov (United States)

    Kougias, Daniel G; Hankosky, Emily R; Gulley, Joshua M; Juraska, Janice M

    2017-03-01

    Beta-hydroxy-beta-methylbutyrate (HMB) is commonly supplemented to maintain muscle in elderly and clinical populations and has potential as a nootropic. Previously, we have shown that in both male and female rats, long-term HMB supplementation prevents age-related dendritic shrinkage within the medial prefrontal cortex (mPFC) and improves cognitive flexibility and working memory performance that are both age- and sex-specific. In this study, we further explore the cognitive effects by assessing visuospatial learning and memory with the Morris water maze. Female rats were ovariectomized at 11months of age to model human menopause. At 12months of age, male and female rats received relatively short- or long-term (1- or 7-month) dietary HMB (450mg/kg/dose) supplementation twice a day prior to testing. Spatial reference learning and memory was assessed across four days in the water maze with four trials daily and a probe trial on the last day. Consistent with previous work, there were age-related deficits in water maze performance in both sexes. However, these deficits were ameliorated in HMB-treated males during training and in both sexes during probe trial performance. Thus, HMB supplementation prevented the age-related decrement in water maze performance, especially in male rats. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Altered strategy in short-term memory for pictures in children with attention-deficit/hyperactivity disorder: a near-infrared spectroscopy study.

    Science.gov (United States)

    Sanefuji, Masafumi; Yamashita, Hiroshi; Torisu, Hiroyuki; Takada, Yui; Imanaga, Hisako; Matsunaga, Mayumi; Ishizaki, Yoshito; Sakai, Yasunari; Yoshida, Keiko; Hara, Toshiro

    2014-07-30

    Strategy in short-term memory for serially presented pictures shifts gradually from a non-phonological to a phonological method as memory ability increases during typical childhood development. However, little is known about the development of this strategic change in children with attention-deficit/hyperactivity disorder (ADHD). To understand the neural basis of ADHD, we investigated short-term memory strategies using near-infrared spectroscopy. ADHD children aged from 6 to 12 years and age- and sex-matched control children were assessed in this study. Regional activity was monitored in the left ventrolateral prefrontal cortex to assess strategies used during short-term memory for visual or phonological objects. We examined the hypothesis that the strategic methods used would be correlated with memory ability. Higher memory ability and the phonological strategy were significantly correlated in the control group but not in the ADHD group. Intriguingly, ADHD children receiving methylphenidate treatment exhibited increased use of phonological strategy compared with those without. In conclusion, we found evidence of an altered strategy in short-term memory in ADHD children. The modulatory effect of methylphenidate indicates its therapeutic efficacy. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  20. Response of water deficit regime and soil amelioration on evapotranspiration loss and water use efficiency of maize (Zea mays l.) in subtropical northeastern Himalayas.

    Science.gov (United States)

    Marwein, M A; Choudhury, B U; Chakraborty, D; Kumar, M; Das, A; Rajkhowa, D J

    2017-05-01

    Rainfed maize production in the hilly ecosystem of Northeastern Himalayas often suffers from moisture and soil acidity induced abiotic stresses. The present study measured evapotranspiration loss (ET c ) of maize crop under controlled condition (pot experiment) of water deficit (W 25 -25 % and W 50 -50 % of field capacity soil moistures) and well watered (W 100  = 100 % of field capacity (FC)) regimes in strong acid soils (pH = 4.3) of the Northeastern Himalayan Region of India. The response of soil ameliorants (lime) and phosphorus (P) nutrition under differential water regimes on ET c losses and water use efficiency was also studied. The measured seasonal ET c loss varied from 124.3 to 270.9 mm across treatment combinations. Imposition of water deficit stress resulted in significant (p losses but was at the cost of delay in tasseling to silking, 47-65 % reduction in dry matter accumulation (DMA), 12-22 days shortening of grain formation period, and complete kernel abortion. Liming @ 4 t ha -1 significantly (p losses and DMA across water regimes but the magnitude of increase was higher in severely water deficit (W 25 ) regime. Unlike lime, P nutrition improved DMA only in well-watered regimes (W 100 ) while seasonal ET c loss was unaffected. Vegetative stage (tillering to tasseling) contributed the maximum ET c losses while weekly crop ET c loss was estimated highest during 11th-14th week after sowing (coincided with blistering stage) and then declined. Water use efficiency estimated from dry matter produced per unit ET c losses and irrigation water used varied from 4.33 to 9.43 g dry matter kg -1  water and 4.21 to 8.56 g dry matter kg -1 , respectively. Among the input factors (water, P, and lime), water regime most strongly influenced the ET c loss, growth duration, grain formation, and water use efficiency of maize.

  1. Arbuscular mycorrhizal fungi improve photosynthetic energy use efficiency and decrease foliar construction cost under recurrent water deficit in woody evergreen species.

    Science.gov (United States)

    Barros, Vanessa; Frosi, Gabriella; Santos, Mariana; Ramos, Diego Gomes; Falcão, Hiram Marinho; Santos, Mauro Guida

    2018-06-01

    Plants suffer recurrent cycles of water deficit in semiarid regions and have several mechanisms to tolerate low water availability. Thus, arbuscular mycorrhizal fungi (AMF) can alleviate deleterious effects of stress. In this study, Cynophalla flexuosa plants, a woody evergreen species from semiarid, when associated with AMF were exposed to two consecutive cycles of water deficit. Leaf primary metabolism, specific leaf area (SLA), leaf construction cost (CC) and photosynthetic energy use efficiency (PEUE) were measured. The maximum stress occurred on seven days (cycle 1) and ten days (cycle 2) after suspending irrigation (photosynthesis close to zero). The rehydration was performed for three days after each maximum stress. In both cycles, plants submitted to water deficit showed reduced gas exchange and leaf relative water content. However, Drought + AMF plants had significantly larger leaf relative water content in cycle 2. At cycle 1, the SLA was larger in non-inoculated plants, while CC was higher in inoculated plants. At cycle 2, Drought + AMF treatment had lower CC and large SLA compared to control, and high PEUE compared to Drought plants. These responses suggest AMFs increase tolerance of C. flexuosa to recurrent water deficit, mainly in cycle 2, reducing the CC, promoting the improvement of SLA and PEUE, leading to higher photosynthetic area. Thus, our result emphasizes the importance of studies on recurrence of water deficit, a common condition in semiarid environments. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  2. Effect of Zeolite and Nitrogen Fertilizer Application under Water Deficit Stress Conditions on Agronomical and Physiological Traits of Rapeseed

    Directory of Open Access Journals (Sweden)

    A. Ghiasvand Ghiasi

    2014-08-01

    Full Text Available In order to evaluation of zeolite and nitrogen fertilizer application effect on agronomic and physilogical traits of rapeseed (cv RGS003 under water deficit stress conditions, an experiment was conducted in factorial based on randomized complete block design with three replications during 2010 in Qazvin region, Iran. In the where, the two levels of irrigation factor as the normal irrigation (irrigation after 80 mm evaporation from class A pan as control and irrigation cease from stem elongation stage till end of growth, nitrogen factor was at three levels (0, 75 and 150 kg.ha-1 and zeolite factor (0 and 10tons per hectare were studied. Results showed that drought stress decreased evaluated traits such as silique per plant (41%, grain per silique (26%, 1000 seed weight (33%, grain yield (52.5%, oil percent (14%, RWC (31.5% and chlorophyll content (35%. Non-application of nitrogen had adverse effects on total traits and reduced them. However, zeolite application at water deficit stress conditions had positive and significant effect on total traits except of oil percent and chlorophyll content, specially improved grain yield and oil yield. Based on the results of this experiment, application of zeolite (10ton/ha-1 through storage and maintenance of water and nutrients, reduced the intensity and harmful effects of stress in plants and enhances crop yield.

  3. Evaluation of Yield and Yield Components of Some Pinto bean (Phaseolus vulgaris L. Genotypes under Late Season Water Deficit Conditions

    Directory of Open Access Journals (Sweden)

    somayyeh soheili movahhed

    2017-10-01

    Full Text Available Introduction Drought or water deficit stress is the most important environmental factor which has severe negative impacts on crop yields, especially when the water stress occurs in the flowering stage. Iran is located in arid and semi-arid areas, therefore, attention to the effects of water deficit stress in different stages of plants growth seems necessary. Bean (Phaseolus vulgaris L. is one of the most important legumes that has a major contribution to human diet and provides an important part of the human protein. According to studies, cultivation areas of legumes in Iran are about 97300 hectares and its total production is about 208350 tons of grain. Bean is a fast-growing plant (Tran and Singh, 2002, thus soil water must be sufficiently available to ensure its desirable growth and yield. The aim of this study was to investigate the effect of drought stress on yield and yield components of some pinto bean (Phaseolus vulgaris L. cultivated in Zanjan province. Materials and methods An experiment was conducted as spilt plot based on randomized complete block design with four replications in Zanjan university research farm. Irrigation levels (control and drought stress and genotypes (Local khomein, Sadri, Ks21193 and Ks21189 were set in the main and subplot, respectively. Water deficit stress was applied during flowering stage (50% of the plants were at anthesis. Sampling was performed to measure yield and yield components at the end of the growth period and final maturity. In this experiment number of pod per Plant, numberof grain per pod, 100 grain weight, grain yield, biological yield and harvest index were measured. Results and Discussion In this experiment it was observed that drought stress, genotype and interact irrigation×genotyps were significantly for all traits except biological yield. Drought stress reduced number of pod perplant, number of grain per pod, 100 grain weight, grain yield, biological yield and Harvest Index. Results

  4. Water deficit during pit hardening enhances phytoprostanes content, a plant biomarker of oxidative stress, in extra virgin olive oil.

    Science.gov (United States)

    Collado-González, Jacinta; Pérez-López, David; Memmi, Houssem; Gijón, M Carmen; Medina, Sonia; Durand, Thierry; Guy, Alexandre; Galano, Jean-Marie; Ferreres, Federico; Torrecillas, Arturo; Gil-Izquierdo, Angel

    2015-04-15

    No previous information exists on the effects of water deficit on the phytoprostanes (PhytoPs) content in extra virgin olive oil from fruits of mature olive (Olea europaea L. cv. Cornicabra) trees during pit hardening. PhytoPs profile in extra virgin olive oil was characterized by the presence of 9-F1t-PhytoP, 9-epi-9-F1t-PhytoP, 9-epi-9-D1t-PhytoP, 9-D1t-PhytoP, 16-B1-PhytoP + ent-16-B1-PhytoP, and 9-L1-PhytoP + ent-9-L1-PhytoP. The qualitative and quantitative differences in PhytoPs content with respect to those reported by other authors indicate a decisive effect of cultivar, oil extraction technology, and/or storage conditions prone to autoxidation. The pit hardening period was critical for extra virgin olive oil composition because water deficit enhanced the PhytoPs content, with the concomitant potential beneficial aspects on human health. From a physiological and agronomical point of view, 9-F1t-PhytoP, 9-epi-9-F1t-PhytoP, and 16-B1-PhytoP + ent-16-B1-PhytoP could be considered as early candidate biomarkers of water stress in olive tree.

  5. Effect of Foliar Application of Phosphorus and Water Deficit on Yield and Yield Components of Winter Wheat (Cultivar Alvand

    Directory of Open Access Journals (Sweden)

    M. Vafapour

    2011-04-01

    Full Text Available In order to study the effects of foliar application of phosphorus (P and water deficit on yield and yield components of winter wheat (Triticum aestivum L., cv. Alvand, a split-plot experiment, with completely randomized blocks design and three replications, was carried out at the Research Farm of Boyer Ahmad Agricultural and Natural Resources Research Station, 13 km west of Yasouj, in 2008-2009. The main plots were irrigation at three levels (1- full irrigation (control, 2- deficit irrigation from the stem elongation to booting stage, and 3- deficit irrigation from booting stage to the end of growth period and the subplots were five levels of foliar application of P fertilizer (0, 3, 6, 9 and 12 kg/ha KH2PO4. The results showed that the effects of different irrigation regimes and foliar application of P were significant on all traits, and their interaction was significant on plant height, number of grain per spike, grain yield and biological yield. Full irrigation and foliar application of 6 kg/ha P produced the highest grain and biological yield (6000 and 14170 kg/ha, respectively and deficit irrigation from the stem elongation to booting stage without foliar application of P produced the lowest grain and biological yield (2920 and 8219 kg/ha, respectively. Foliar application of P affects significantly the evaluated traits only in drought-stress treatments and its effect was not significant in full irrigation treatment. In general, foliar application of 9 kg/ha P compensated the losses in wheat due to drought stress.

  6. Changes in microbial water quality in RAS following altered feed loading

    DEFF Research Database (Denmark)

    Rojas-Tirado, Paula Andrea; Pedersen, Per Bovbjerg; Vadstein, Olav

    2018-01-01

    and inorganic nutrients available for microbial growth in RAS. How these nutrient inputs affect and regulate bacteria in RAS water is, however, unclear. To investigate this relationship and the associated water quality dynamics, the effects of altered feed loading on microbial water quality in RAS was studied....... The study included six independent, identical pilot-scale RAS, each with a total volume of 1.7 m3 (make-up water: 80 L/day) stocked with juvenile rainbow trout (Oncorhynchus mykiss). All systems had been operating with constant and identical feed loading of 3.13 kg feed/m3 make-up water for a period......Intensive recirculating aquaculture systems (RAS) with its hyper-eutrophic water offer ideal conditions for bacterial growth, abundance and activity, potentially affecting fish and system performance. Feed composition and feed loading in particular will have significant impact on organic...

  7. Indicators of streamflow alteration, habitat fragmentation, impervious cover, and water quality for Massachusetts stream basins

    Science.gov (United States)

    Weiskel, Peter K.; Brandt, Sara L.; DeSimone, Leslie A.; Ostiguy, Lance J.; Archfield, Stacey A.

    2010-01-01

    Massachusetts streams and stream basins have been subjected to a wide variety of human alterations since colonial times. These alterations include water withdrawals, treated wastewater discharges, construction of onsite septic systems and dams, forest clearing, and urbanization—all of which have the potential to affect streamflow regimes, water quality, and habitat integrity for fish and other aquatic biota. Indicators were developed to characterize these types of potential alteration for subbasins and groundwater contributing areas in Massachusetts. The potential alteration of streamflow by the combined effects of withdrawals and discharges was assessed under two water-use scenarios. Water-use scenario 1 incorporated publicly reported groundwater withdrawals and discharges, direct withdrawals from and discharges to streams, and estimated domestic-well withdrawals and septic-system discharges. Surface-water-reservoir withdrawals were excluded from this scenario. Water-use scenario 2 incorporated all the types of withdrawal and discharge included in scenario 1 as well as withdrawals from surface-water reservoirs—all on a long-term, mean annual basis. All withdrawal and discharge data were previously reported to the State for the 2000–2004 period, except domestic-well withdrawals and septic-system discharges, which were estimated for this study. The majority of the state’s subbasins and groundwater contributing areas were estimated to have relatively minor (less than 10 percent) alteration of streamflow under water-use scenario 1 (seasonally varying water use; no surface-water-reservoir withdrawals). However, about 12 percent of subbasins and groundwater contributing areas were estimated to have extensive alteration of streamflows (greater than 40 percent) in August; most of these basins were concentrated in the outer metropolitan Boston region. Potential surcharging of streamflow in August was most commonly indicated for main-stem river subbasins, although

  8. Increased water deficit decreases Douglas fir growth throughout western US forests.

    Science.gov (United States)

    Restaino, Christina M; Peterson, David L; Littell, Jeremy

    2016-08-23

    Changes in tree growth rates can affect tree mortality and forest feedbacks to the global carbon cycle. As air temperature increases, evaporative demand also increases, increasing effective drought in forest ecosystems. Using a spatially comprehensive network of Douglas fir (Pseudotsuga menziesii) chronologies from 122 locations that represent distinct climate environments in the western United States, we show that increased temperature decreases growth via vapor pressure deficit (VPD) across all latitudes. Using an ensemble of global circulation models, we project an increase in both the mean VPD associated with the lowest growth extremes and the probability of exceeding these VPD values. As temperature continues to increase in future decades, we can expect deficit-related stress to increase and consequently Douglas fir growth to decrease throughout its US range.

  9. Managing urban water systems with significant adaptation deficits - a unified framework for secondary cities

    Science.gov (United States)

    Pathirana, A.; Radhakrishnan, M.; Zevenbergen, C.; Quan, N. H.

    2016-12-01

    The need to address the shortcomings of urban systems - adaptation deficit - and shortcomings in response to climate change - `adaptation gap' - are both major challenges in maintaining the livability and sustainability of cities. However, the adaptation actions defined in terms of type I (addressing adaptation deficits) and type II (addressing adaptation gaps), often compete and conflict each other in the secondary cities of the global south. Extending the concept of the environmental Kuznets curve, this paper argues that a unified framework that calls for synergistic action on type I and type II adaptation is essential in order for these cities to maintain their livability, sustainability and resilience facing extreme rates of urbanization and rapid onset of climate change. The proposed framework has been demonstrated in Can Tho, Vietnam, where there are significant adaptation deficits due to rapid urbanisation and adaptation gaps due to climate change and socio-economic changes. The analysis in Can Tho reveals the lack of integration between type I and type II measures that could be overcome by closer integration between various stakeholders in terms of planning, prioritising and implementing the adaptation measures.

  10. ESKIMO1 disruption in Arabidopsis alters vascular tissue and impairs water transport.

    Directory of Open Access Journals (Sweden)

    Valérie Lefebvre

    Full Text Available Water economy in agricultural practices is an issue that is being addressed through studies aimed at understanding both plant water-use efficiency (WUE, i.e. biomass produced per water consumed, and responses to water shortage. In the model species Arabidopsis thaliana, the ESKIMO1 (ESK1 gene has been described as involved in freezing, cold and salt tolerance as well as in water economy: esk1 mutants have very low evapo-transpiration rates and high water-use efficiency. In order to establish ESK1 function, detailed characterization of esk1 mutants has been carried out. The stress hormone ABA (abscisic acid was present at high levels in esk1 compared to wild type, nevertheless, the weak water loss of esk1 was independent of stomata closure through ABA biosynthesis, as combining mutant in this pathway with esk1 led to additive phenotypes. Measurement of root hydraulic conductivity suggests that the esk1 vegetative apparatus suffers water deficit due to a defect in water transport. ESK1 promoter-driven reporter gene expression was observed in xylem and fibers, the vascular tissue responsible for the transport of water and mineral nutrients from the soil to the shoots, via the roots. Moreover, in cross sections of hypocotyls, roots and stems, esk1 xylem vessels were collapsed. Finally, using Fourier-Transform Infrared (FTIR spectroscopy, severe chemical modifications of xylem cell wall composition were highlighted in the esk1 mutants. Taken together our findings show that ESK1 is necessary for the production of functional xylem vessels, through its implication in the laying down of secondary cell wall components.

  11. Water deficit affects mesophyll limitation of leaves more strongly in sun than in shade in two contrasting Picea asperata populations.

    Science.gov (United States)

    Duan, Baoli; Li, Yan; Zhang, Xiaolu; Korpelainen, Helena; Li, Chunyang

    2009-12-01

    The aim of this study was to examine the response of internal conductance to CO(2) (g(i)) to soil water deficit and contrasting light conditions, and their consequences on photosynthetic physiology in two Picea asperata Mast. populations originating from wet and dry climate regions of China. Four-year-old trees were subjected to two light treatments (30% and 100% of full sunlight) and two watering regimes (well watered, drought) for 2 years. In both tested populations, drought significantly decreased g(i) and the net photosynthesis rate (A) and increased carbon isotope composition (delta(13)C) values in both light treatments, in particular in the sun. Moreover, drought resulted in a significantly higher relative limitation due to stomatal conductance (L(s)) in both light treatments and higher relative limitation due to internal conductance (L(i)) and abscisic acid (ABA) in the sun plants. The results also showed that L(i) (0.26-0.47) was always greater than L(s) (0.12-0.28). On the other hand, drought significantly decreased the ratio of chloroplastic to internal CO(2) concentration (C(c)/C(i)), photosynthetic nitrogen utilization efficiency (PNUE) and total biomass in the sun plants of the wet climate population, whereas there were no significant changes in these parameters in the dry climate population. Our results also showed that the dry climate population possessed higher delta(13)C values with higher ratio of internal conductance to stomatal conductance (g(i)/g(s)), suggesting that increasing the g(i)/g(s) ratio enhances water-use efficiency (WUE) in plants evolved in arid environments. Thus, we propose that the use of the g(i)/g(s) parameter to screen P. asperata plants with higher water deficit tolerance is certainly worthy of consideration. Furthermore, g(i) is an important variable, which reflects the population differences in PNUE, and it should thus be included in plant physiological investigations related to leaf economics.

  12. Malbec grape (Vitis vinifera L.) responses to the environment: Berry phenolics as influenced by solar UV-B, water deficit and sprayed abscisic acid.

    Science.gov (United States)

    Alonso, Rodrigo; Berli, Federico J; Fontana, Ariel; Piccoli, Patricia; Bottini, Rubén

    2016-12-01

    High-altitude vineyards receive elevated solar ultraviolet-B (UV-B) levels so producing high quality berries for winemaking because of induction in the synthesis of phenolic compounds. Water deficit (D) after veraison, is a commonly used tool to regulate berry polyphenols concentration in red wine cultivars. Abscisic acid (ABA) plays a crucial role in the acclimation to environmental factors/signals (including UV-B and D). The aim of the present study was to evaluate independent and interactive effects of high-altitude solar UV-B, moderate water deficit and ABA applications on Vitis vinifera cv. Malbec berries. The experiment was conducted during two growing seasons with two treatments of UV-B (+UV-B and -UV-B), watering (+D and -D) and ABA (+ABA and -ABA), in a factorial design. Berry fresh weight, sugar content, fruit yield, phenolic compounds profile and antioxidant capacity (ORAC) were analyzed at harvest. Previous incidence of high UV-B prevented deleterious effects of water deficit, i.e. berry weight reduction and diminution of sugar accumulation. High UV-B increased total phenols (mainly astilbin, quercetin and kaempferol) and ORAC, irrespectively of the combination with other factors. Fruit yield was reduced by combining water deficit and high UV-B or water deficit and ABA. Two applications of ABA were enough to induced biochemical changes increasing total anthocyanins, especially those with higher antioxidant capacity. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  13. Partitioning between primary and secondary metabolism of carbon allocated to roots in four maize genotypes under water deficit and its effects on productivity

    Directory of Open Access Journals (Sweden)

    Alyne Oliveira Lavinsky

    2015-10-01

    Full Text Available Plants may respond to drought by altering biomass allocation to shoots and roots or by changing the metabolic activities in these organs. To determine how drought changes the partitioning of carbon allocated to growth and secondary metabolism in maize roots and how it affects photosynthesis (A and productivity in maize, we evaluated leaf gas exchange, yield componentes, root morphology, and primary and secondary metabolites including total soluble sugars (TSS, starch (S, phenolics (PHE, and lignin (LIG. Data were collected from pot-grown plants of four maize genotypes: BRS 1010 and 2B710 (sensitive genotypes and DKB390 and BRS1055 (tolerant genotypes under two soil water tensions: field capacity (FC, − 18 kPa and water deficit (WD, − 138 kPa. WD was applied at the pre-flowering stage for 12 days and then the water supply was restored and maintained at optimum levels until the end of the cycle. For genotype BRS 1055 under FC, the greatest A did not result in greater grain biomass (DGB because the accumulated photoassimilates had already filled the cells, and thus the excessive TSS synthesized in leaves was allocated to roots in large amounts. However, the sharp decrease in A caused by WD imposition in this genotype did not affect the influx pressure of leaf TSS, which was due largely to conversion of primary metabolites to PHE compounds to increase the length of fine roots. In leaves of DKB390 under WD, both S and TSS were reduced, whereas PHE were increased to prevent excessive water loss and xylem cavitation. Under WD, both BRS1010 and 2B710 genotypes displayed reduced allocation of biomass to shoots and roots and LIG content in leaves, as well as lower A and DGB values. In BRS1010 this response was coupled to S decrease in leaves and TSS increase in roots, whereas in 2B710 there was a concomitant S increase in roots.

  14. Inorganic mercury exposure in drinking water alters essential metal homeostasis in pregnant rats without altering rat pup behavior.

    Science.gov (United States)

    Oliveira, Cláudia S; Oliveira, Vitor A; Costa, Lidiane M; Pedroso, Taíse F; Fonseca, Mariana M; Bernardi, Jamile S; Fiuza, Tiago L; Pereira, Maria E

    2016-10-01

    The aim of this work was to investigate the effects of HgCl 2 exposure in the doses of 0, 10 and 50μg Hg 2+ /mL in drinking water during pregnancy on tissue essential metal homeostasis, as well as the effects of HgCl 2 exposure in utero and breast milk on behavioral tasks. Pregnant rats exposed to both inorganic mercury doses presented high renal Hg content and an increase in renal Cu and hepatic Zn levels. Mercury exposure increased fecal Hg and essential metal contents. Pups exposed to inorganic Hg presented no alterations in essential metal homeostasis or in behavioral task markers of motor function. In conclusion, this work showed that the physiologic pregnancy and lactation states protected the offspring from adverse effects of low doses of Hg 2+ . This protection is likely to be related to the endogenous scavenger molecule, metallothionein, which may form an inert complex with Hg 2+ . Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Altered white matter tract property related to impaired focused attention, sustained attention, cognitive impulsivity and vigilance in attention-deficit/ hyperactivity disorder.

    Science.gov (United States)

    Chiang, Huey-Ling; Chen, Yu-Jen; Lo, Yu-Chun; Tseng, Wen-Yih I; Gau, Susan S

    2015-09-01

    The neural substrate for clinical symptoms and neuropsychological performance in individuals with attention-deficit/hyperactivity disorder (ADHD) has rarely been studied and has yielded inconsistent results. We sought to compare the microstructural property of fibre tracts associated with the prefrontal cortex and its association with ADHD symptoms and a wide range of attention performance in youth with ADHD and healthy controls. We assessed youths with ADHD and age-, sex-, handedness-, coil- and intelligence-matched controls using the Conners' Continuous Performance Test (CCPT) for attention performance and MRI. The 10 target tracts, including the bilateral frontostriatal tracts (caudate to dorsolateral prefrontal cortex, ventrolateral prefrontal cortex and orbitofrontal cortex), superior longitudinal fasciculus (SLF) and cingulum bundle were reconstructed using diffusion spectrum imaging tractography. We computed generalized fractional anisotropy (GFA) values to indicate tract-specific microstructural property. We included 50 youths with ADHD and 50 healthy controls in our study. Youths with ADHD had lower GFA in the left frontostriatal tracts, bilateral SLF and right cingulum bundle and performed worse in the CCPT than controls. Furthermore, alteration of the right SLF GFA was most significantly associated with the clinical symptom of inattention in youths with ADHD. Finally, youths with ADHD had differential association patterns of the 10 fibre tract GFA values with attention performance compared with controls. Ten of the youths with ADHD were treated with methylphenidate, which may have long-term effects on microstructural property. Our study highlights the importance of the SLF, cingulum bundle and frontostriatal tracts for clinical symptoms and attention performance in youths with ADHD and demonstrates the involvement of different fibre tracts in attention performance in these individuals.

  16. Delaying chloroplast turnover increases water-deficit stress tolerance through the enhancement of nitrogen assimilation in rice.

    Science.gov (United States)

    Sade, Nir; Umnajkitikorn, Kamolchanok; Rubio Wilhelmi, Maria Del Mar; Wright, Matthew; Wang, Songhu; Blumwald, Eduardo

    2018-02-12

    Abiotic stress-induced senescence in crops is a process particularly affecting the photosynthetic apparatus, decreasing photosynthetic activity and inducing chloroplast degradation. A pathway for stress-induced chloroplast degradation that involves the CHLOROPLAST VESICULATION (CV) gene was characterized in rice (Oryza sativa) plants. OsCV expression was up-regulated with the age of the plants and when plants were exposed to water-deficit conditions. The down-regulation of OsCV expression contributed to the maintenance of the chloroplast integrity under stress. OsCV-silenced plants displayed enhanced source fitness (i.e. carbon and nitrogen assimilation) and photorespiration, leading to water-deficit stress tolerance. Co-immunoprecipitation, intracellular co-localization, and bimolecular fluorescence demonstrated the in vivo interaction between OsCV and chloroplastic glutamine synthetase (OsGS2), affecting source-sink relationships of the plants under stress. Our results would indicate that the OsCV-mediated chloroplast degradation pathway is involved in the regulation of nitrogen assimilation during stress-induced plant senescence. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  17. Phenomics allows identification of genomic regions affecting maize stomatal conductance with conditional effects of water deficit and evaporative demand.

    Science.gov (United States)

    Prado, Santiago Alvarez; Cabrera-Bosquet, Llorenç; Grau, Antonin; Coupel-Ledru, Aude; Millet, Emilie J; Welcker, Claude; Tardieu, François

    2018-02-01

    Stomatal conductance is central for the trades-off between hydraulics and photosynthesis. We aimed at deciphering its genetic control and that of its responses to evaporative demand and water deficit, a nearly impossible task with gas exchanges measurements. Whole-plant stomatal conductance was estimated via inversion of the Penman-Monteith equation from data of transpiration and plant architecture collected in a phenotyping platform. We have analysed jointly 4 experiments with contrasting environmental conditions imposed to a panel of 254 maize hybrids. Estimated whole-plant stomatal conductance closely correlated with gas-exchange measurements and biomass accumulation rate. Sixteen robust quantitative trait loci (QTLs) were identified by genome wide association studies and co-located with QTLs of transpiration and biomass. Light, vapour pressure deficit, or soil water potential largely accounted for the differences in allelic effects between experiments, thereby providing strong hypotheses for mechanisms of stomatal control and a way to select relevant candidate genes among the 1-19 genes harboured by QTLs. The combination of allelic effects, as affected by environmental conditions, accounted for the variability of stomatal conductance across a range of hybrids and environmental conditions. This approach may therefore contribute to genetic analysis and prediction of stomatal control in diverse environments. © 2017 John Wiley & Sons Ltd.

  18. Effects of Salicylic Acid on Some Morphophysiological Characteristics of Border Flowers from Asteraceae Family under Water Deficit

    Directory of Open Access Journals (Sweden)

    majid zargarian

    2017-02-01

    Full Text Available Introduction: In order to improve physical and mental human healthy, development of the urban area landscape is necessary. Water deficit is one of the most important problems in arid and semi- arid regions. Water deficit causes to reduce growth of different plants parts, including roots, aerial parts, leaf area, height, dry weight, proteins, amino acids and chlorophyll. Using drought tolerance plantsisone solution. Moreover, one physiological method to decrease the hazardous effects of environmental stresses on plants is to applyplant growth regulators such as salicylic acid (SA. SA is one of the plant phenolic compounds in low amounts (mg/g wet weight or lower. This hormone can perform an important role in resistance to stresses. Asteraceae is one of the biggest plant families with over 20,000 species which is distributed worldwide in moderate and tropical regions. A lot of border flowers of this family are widely used in landscaping. Toselect drought tolerance flowers and application of materials that reducing stress effects, this experiment was conducted to investigate the effects of salicylic acid on some morphological and physiological characteristics of five border flowers of this family. Materials and Methods: The field experiment was conducted as split plot on randomized complete blocks design with four replications in which factors included two levels of water deficit (50, 100% FC as main plot and two levels of SA (0, 1mmol/L-1 as sub plot in the horticulturedepartment of faculty of Agriculture atFerdowsi University of Mashhad. In this investigation five border flowers (Ageratum houstonianum‘Blue Danube’, Tagetserecta ‘Discovery Yellow’, Tagetspatula‘Hero Harmony’, Zinnia elegans ‘Lilliput rose’andCallistephuschinensis ‘Milady Mix’ of Asteraceae family were chosen for study. The soil mixture was analyzed before starting the test. According to the result of physicochemical analysis of the soil, it had loamy texture

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

    Science.gov (United States)

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

    1990-01-01

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

  20. Report on static hydrothermal alteration studies of Topopah Spring tuff waters in J-13 water at 150{sup 0}C

    Energy Technology Data Exchange (ETDEWEB)

    Knauss, K.G.; Beiriger, W.B.

    1984-08-31

    This report presents the results of preliminary experimental work done to define the package environment in a potential nuclear waste repository in the Topopah Spring Member of the Paintbrush Tuff. The work is supported by the Nevada Nuclear Waste Storage Investigations (NNWSI) Project as a part of the Waste Package task to design a package suitable for waste storage within volcanic units at the Nevada Test Site. Static hydrothermal alteration experiments were run for 4 months using polished wafers either fully submerged in an appropriate natural ground water or exposed to water-saturated air with enough excess water to allow refluxing. The aqueous results agreed favorably with similar experiments run using crushed tuff, and the use of solid polished wafers allowed us to directly evaluate the effects of reaction on the tuff. The results are preliminary in the sense that these experiments were run in Teflon-lined, static autoclaves, whereas subsequent experiments have been run in Dickson-type gold-cell rocking autoclaves. The results predict relatively minor changes in water chemistry, very minor alteration of the host rock, and the production of slight amounts of secondary minerals, when liquid water could return to the rock pores following the temperature maximum during the thermal period. 7 references, 16 figures, 10 tables.

  1. Yield Response of Spring Maize to Inter-Row Subsoiling and Soil Water Deficit in Northern China.

    Science.gov (United States)

    Liu, Zhandong; Qin, Anzhen; Zhao, Ben; Ata-Ul-Karim, Syed Tahir; Xiao, Junfu; Sun, Jingsheng; Ning, Dongfeng; Liu, Zugui; Nan, Jiqin; Duan, Aiwang

    2016-01-01

    Long-term tillage has been shown to induce water stress episode during crop growth period due to low water retention capacity. It is unclear whether integrated water conservation tillage systems, such asspringdeepinter-row subsoiling with annual or biennial repetitions, can be developed to alleviate this issue while improve crop productivity. Experimentswere carried out in a spring maize cropping system on Calcaric-fluvicCambisolsatJiaozuoexperimentstation, northern China, in 2009 to 2014. Effects of threesubsoiling depths (i.e., 30 cm, 40 cm, and 50 cm) in combination with annual and biennial repetitionswasdetermined in two single-years (i.e., 2012 and 2014)againstthe conventional tillage. The objectives were to investigateyield response to subsoiling depths and soil water deficit(SWD), and to identify the most effective subsoiling treatment using a systematic assessment. Annualsubsoiling to 50 cm (AS-50) increased soil water storage (SWS, mm) by an average of8% in 0-20 cm soil depth, 19% in 20-80 cm depth, and 10% in 80-120 cm depth, followed by AS-40 and BS-50, whereas AS-30 and BS-30 showed much less effects in increasing SWS across the 0-120 cm soil profile, compared to the CK. AS-50 significantly reduced soil water deficit (SWD, mm) by an average of123% during sowing to jointing, 318% during jointing to filling, and 221% during filling to maturity, compared to the CK, followed by AS-40 and BS-50. An integrated effect on increasing SWS and reducing SWD helped AS-50 boost grain yield by an average of 31% and biomass yield by 30%, compared to the CK. A power function for subsoiling depth and a negative linear function for SWD were used to fit the measured yields, showing the deepest subsoiling depth (50 cm) with the lowest SWD contributed to the highest yield. Systematic assessment showed that AS-50 received the highest evaluation index (0.69 out of 1.0) among all treatments. Deepinter-row subsoilingwith annual repetition significantly boosts yield by

  2. Storms do not alter long-term watershed development influences on coastal water quality.

    Science.gov (United States)

    Chen, Yushun; Cebrian, Just; Lehrter, John; Christiaen, Bart; Stutes, Jason; Goff, Josh

    2017-09-15

    A twelve year (2000-2011) study of three coastal lagoons in the Gulf of Mexico was conducted to assess the impacts of local watershed development and tropical storms on water quality. The lagoons have similar physical and hydrological characteristics, but differ substantially in the degree of watershed urban development and nutrient loading rates. In total the lagoons experienced 22 storm events during the period studied. Specifically, we examine (1) whether there are influences on water quality in the lagoons from watershed development, (2) whether there are influences on water quality in the lagoons from storm activity, and (3) whether water quality is affected to a greater degree by watershed development versus storm activity. The two urbanized lagoons typically showed higher water-column nitrate, dissolved organic nitrogen, and phosphate compared with the non-urbanized lagoon. One of the urbanized lagoons had higher water-column chlorophyll a concentrations than the other two lagoons on most sampling dates, and higher light extinction coefficients on some sampling dates. The non-urbanized lagoon had higher water-column dissolved oxygen concentrations than other lagoons on many sampling dates. Our results suggest long-term influences of watershed development on coastal water quality. We also found some evidence of significant storm effects on water quality, such as increased nitrate, phosphate, and dissolved oxygen, and decreased salinity and water temperature. However, the influences of watershed development on water quality were greater. These results suggest that changes in water quality induced by human watershed development pervade despite the storm effects. These findings may be useful for environmental management since they suggest that storms do not profoundly alter long-term changes in water quality that resulted from human development of watersheds. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Effect of alteration zones on water quality: a case study from Biga Peninsula, Turkey.

    Science.gov (United States)

    Baba, Alper; Gunduz, Orhan

    2010-04-01

    Widespread and intense zones of silicified, propylitic, and argillic alteration can be found in the Can volcanics of Biga Peninsula, northwest Turkey. Most of the springs in the study area surface out from the boundary between fractured aquifer (silicified zone) and impervious boundary (argillic zone). This study focuses on two such springs in Kirazli area (Kirazli and Balaban springs) with a distinct quality pattern. Accordingly, field parameters (temperature, pH, and electrical conductivity), major anion and cation (sodium, potassium, calcium, magnesium, chloride, bicarbonate, and sulfate), heavy metals (aluminum, arsenic, barium, chromium, cobalt, cupper, iron, lithium, manganese, nickel, lead, and zinc), and isotopes (oxygen-18, deuterium, and tritium) were determined in water samples taken from these springs during 2005 through 2007. The chemical analyses showed that aluminum concentrations were found to be two orders of magnitude greater in Kirazli waters (mean value 13813.25 microg/L). The levels of this element exceeded the maximum allowable limits given in national and international standards for drinking-water quality. In addition, Balaban and Kirazli springs are >55 years old according to their tritium levels; Kirazli spring is older than Balaban spring. Kirazli spring is also more enriched than Balaban spring based in oxygen-18 and deuterium values. Furthermore, Kirazli spring water has been in contact with altered rocks longer than Balaban spring water, according to its relatively high chloride and electrical conductivity values.

  4. Effects of Foliar Applications of Sulfur, Nitrogen and Phosphorus on Castor Bean (Ricinus cmmunis L. Seed Yield and its Components under Water Deficit Conditions

    Directory of Open Access Journals (Sweden)

    M. Mosavi

    2015-08-01

    Full Text Available To determine the effects of foliar applications of some macroelements on castor seed yield and its components under drought stress conditions, an experiment was conducted at the Agricultural Research Center of East Azerbaijan province. A factorial experiment, based on randomized complete block design with three replications, was carried out during 2013 growing season. Treatment factors consisted of irrigations with two levels (no water deficit and water deficit during grain filling stage and of foliar applications of macroelements with four levels [control, wettable sulfur (0.2 percent, nitrogen (urea: 0.6 percent and phosphor (super phosphate triple: 0.4 percent. Traits studied were: plant height, number of inflorescence, number of lateral branches, number of leaves, leaf temperature, relative water content, number of seeds per plant, 1000-kernal weight and seed yield. All traits, except number of inflorescence, were affected significantly by drought stress. Water deficit reduced plant height, number of leaves, number of seeds per plant, 1000-kernal weight, seed yield, relative water content, while it increased leaf temperature. Number of lateral branches was affected significantly by interaction between factors. Maximum latral branches (1.86 were obtained under non-stress treatment with nitrogen foliar application. Moderate drought stress had significant effect on leaf temperature and relative water content. It seems that, these traits can be used in determination of water deficit effects on castor bean.

  5. Water in the Early Solar System: Infrared Studies of Aqueously Altered and Minimally Processed Asteroids

    Science.gov (United States)

    McAdam, Margaret M.

    This thesis investigates connections between low albedo asteroids and carbonaceous chondrite meteorites using spectroscopy. Meteorites and asteroids preserve information about the early solar system including accretion processes and parent body processes active on asteroids at these early times. One process of interest is aqueous alteration. This is the chemical reaction between coaccreted water and silicates producing hydrated minerals. Some carbonaceous chondrites have experienced extensive interactions with water through this process. Since these meteorites and their parent bodies formed close to the beginning of the Solar System, these asteroids and meteorites may provide clues to the distribution, abundance and timing of water in the Solar nebula at these times. Chapter 2 of this thesis investigates the relationships between extensively aqueously altered meteorites and their visible, near and mid-infrared spectral features in a coordinated spectral-mineralogical study. Aqueous alteration is a parent body process where initially accreted anhydrous minerals are converted into hydrated minerals in the presence of coaccreted water. Using samples of meteorites with known bulk properties, it is possible to directly connect changes in mineralogy caused by aqueous alteration with spectral features. Spectral features in the mid-infrared are found to change continuously with increasing amount of hydrated minerals or degree of alteration. Building on this result, the degrees of alteration of asteroids are estimated in a survey of new asteroid data obtained from SOFIA and IRTF as well as archived the Spitzer Space Telescope data. 75 observations of 73 asteroids are analyzed and presented in Chapter 4. Asteroids with hydrated minerals are found throughout the main belt indicating that significant ice must have been present in the disk at the time of carbonaceous asteroid accretion. Finally, some carbonaceous chondrite meteorites preserve amorphous iron-bearing materials

  6. Effects of Recent Minimum Temperature and Water Deficit Increases on Pinus pinaster Radial Growth and Wood Density in Southern Portugal

    Science.gov (United States)

    Kurz-Besson, Cathy B.; Lousada, José L.; Gaspar, Maria J.; Correia, Isabel E.; David, Teresa S.; Soares, Pedro M. M.; Cardoso, Rita M.; Russo, Ana; Varino, Filipa; Mériaux, Catherine; Trigo, Ricardo M.; Gouveia, Célia M.

    2016-01-01

    Western Iberia has recently shown increasing frequency of drought conditions coupled with heatwave events, leading to exacerbated limiting climatic conditions for plant growth. It is not clear to what extent wood growth and density of agroforestry species have suffered from such changes or recent extreme climate events. To address this question, tree-ring width and density chronologies were built for a Pinus pinaster stand in southern Portugal and correlated with climate variables, including the minimum, mean and maximum temperatures and the number of cold days. Monthly and maximum daily precipitations were also analyzed as well as dry spells. The drought effect was assessed using the standardized precipitation-evapotranspiration (SPEI) multi-scalar drought index, between 1 to 24-months. The climate-growth/density relationships were evaluated for the period 1958-2011. We show that both wood radial growth and density highly benefit from the strong decay of cold days and the increase of minimum temperature. Yet the benefits are hindered by long-term water deficit, which results in different levels of impact on wood radial growth and density. Despite of the intensification of long-term water deficit, tree-ring width appears to benefit from the minimum temperature increase, whereas the effects of long-term droughts significantly prevail on tree-ring density. Our results further highlight the dependency of the species on deep water sources after the juvenile stage. The impact of climate changes on long-term droughts and their repercussion on the shallow groundwater table and P. pinaster’s vulnerability are also discussed. This work provides relevant information for forest management in the semi-arid area of the Alentejo region of Portugal. It should ease the elaboration of mitigation strategies to assure P. pinaster’s production capacity and quality in response to more arid conditions in the near future in the region. PMID:27570527

  7. Effects of Recent Minimum Temperature and Water Deficit Increases on Pinus pinaster Radial Growth and Wood Density in Southern Portugal.

    Science.gov (United States)

    Kurz-Besson, Cathy B; Lousada, José L; Gaspar, Maria J; Correia, Isabel E; David, Teresa S; Soares, Pedro M M; Cardoso, Rita M; Russo, Ana; Varino, Filipa; Mériaux, Catherine; Trigo, Ricardo M; Gouveia, Célia M

    2016-01-01

    Western Iberia has recently shown increasing frequency of drought conditions coupled with heatwave events, leading to exacerbated limiting climatic conditions for plant growth. It is not clear to what extent wood growth and density of agroforestry species have suffered from such changes or recent extreme climate events. To address this question, tree-ring width and density chronologies were built for a Pinus pinaster stand in southern Portugal and correlated with climate variables, including the minimum, mean and maximum temperatures and the number of cold days. Monthly and maximum daily precipitations were also analyzed as well as dry spells. The drought effect was assessed using the standardized precipitation-evapotranspiration (SPEI) multi-scalar drought index, between 1 to 24-months. The climate-growth/density relationships were evaluated for the period 1958-2011. We show that both wood radial growth and density highly benefit from the strong decay of cold days and the increase of minimum temperature. Yet the benefits are hindered by long-term water deficit, which results in different levels of impact on wood radial growth and density. Despite of the intensification of long-term water deficit, tree-ring width appears to benefit from the minimum temperature increase, whereas the effects of long-term droughts significantly prevail on tree-ring density. Our results further highlight the dependency of the species on deep water sources after the juvenile stage. The impact of climate changes on long-term droughts and their repercussion on the shallow groundwater table and P. pinaster's vulnerability are also discussed. This work provides relevant information for forest management in the semi-arid area of the Alentejo region of Portugal. It should ease the elaboration of mitigation strategies to assure P. pinaster's production capacity and quality in response to more arid conditions in the near future in the region.

  8. Changes in carbon and nitrogen allocation, growth and grain yield induced by arbuscular mycorrhizal fungi in wheat (Triticum aestivum L.) subjected to a period of water deficit

    DEFF Research Database (Denmark)

    Zhou, Qin; Ravnskov, Sabine; Jiang, Dong

    2015-01-01

    Drought is a major abiotic factor limiting agricultural crop production. One of the effective ways to increase drought resistance in plants could be to optimize the exploitation of symbiosis with arbuscular mycorrhizal fungi (AMF). Hypothesizing that alleviation of water deficits by AMF in wheat...... will help maintain photosynthetic carbon-use, we studied the role of AMF on gas-exchange, light-use efficiencies, carbon/nitrogen ratios and growth and yield parameters in the contrasting wheat (Triticum aestivum L.) cultivars ‘Vinjett’ and ‘1110’ grown with/without AMF symbiosis. Water deficits applied...... at the floret initiation stage significantly decreased rates of photosynthetic carbon gain, transpiration and stomatal conductance in the two wheat cultivars. AMF increased the rates of photosynthesis, transpiration and stomatal conductance under drought conditions. Water deficits decreased electron transport...

  9. Temporal dynamics of stomatal conductance of plants under water deficit: can homeostasis be improved by more complex dynamics?

    Directory of Open Access Journals (Sweden)

    Gustavo Maia Souza

    2004-07-01

    Full Text Available In this study we hypothesized that chaotic or complex behavior of stomatal conductance could improve plant homeostasis after water deficit. Stomatal conductance of sunflower and sugar beet leaves was measured in plants grown either daily irrigation or under water deficit using an infrared gas analyzer. All measurements were performed under controlled environmental conditions. In order to measure a consistent time series, data were scored with time intervals of 20s during 6h. Lyapunov exponents, fractal dimensions, KS entropy and relative LZ complexity were calculated. Stomatal conductance in both irrigated and non-irrigated plants was chaotic-like. Plants under water deficit showed a trend to a more complex behaviour, mainly in sunflower that showed better homeostasis than in sugar beet. Some biological implications are discussed.Este estudo testou a hipótese de que a condutância estomática de uma população de estômatos em uma folha poderia apresentar um comportamento caótico ou complexo sob diferentes condições hídricas, o que poderia favorecer a capacidade homeostática das plantas. A condutância estomática em folhas de girassol e de beterraba cultivadas com irrigação diária e sob deficiência hídrica foi medida com um analisador de gás por infra-vermelho em condições controladas. Os dados foram registrados a cada 20s durante 6h. As séries temporais obtidas foram analisadas por meio dos coeficientes de Lyapunov, dimensão fractal, entropia KS e complexidade LZ relativa. A condutância estomática nas plantas cultivadas com e sem deficiência hídrica exibiu um comportamento provavelmente caótico. As plantas sob estresse hídrico mostraram uma tendência para um comportamento mais complexo, principalmente as plantas de girassol cuja capacidade homeostática foi superior. Algumas implicações biológicas destes comportamentos são discutidas no texto.

  10. Implications of Water Budget Deficits on Socio-Economic Stability and Food Security in the Arabian Peninsula and in North Africa

    Science.gov (United States)

    Mazzoni, A.; Heggy, E.; Scabbia, G.

    2017-12-01

    Water scarcity in the Arabian Peninsula and North Africa is accentuated by forecasted climatic variability, decreasing precipitation volumes and projected population growth, urbanization and economic development, increasing water demand. These factors impose uncertainties on food security and socio-economic stability in the region. We develop a water-budget model combining hydrologic, climatic and economic data to quantify water deficit volumes and groundwater depletion rates for the main aquifer systems in the area, taking into account three different climatic scenarios, and calculated from the precipitation forecast elaborated in the CSIRO, ECHAM4 and HADCM3 global circulation models from 2016 to 2050 over 1-year intervals. Water demand comprises water requirements for each economic sector, derived from data such as population, GDP, cropland cover and electricity production, and is based upon the five different SSPs. Conventional and non-conventional water resource supply data are retrieved from FAO Aquastat and institutional databases. Our results suggest that in the next 35 years, in North Africa, only Egypt and Libya will exhibit severe water deficits with respectively 44% and 89.7% of their current water budgets by 2050 (SSP2-AVG climatic scenario), while all the countries in the Arabian Peninsula will be subjected to water stress; the majority of small-size aquifers in the Arabian Peninsula will reach full depletion by 2050. In North Africa, the fossil aquifers' volume loss will be 1-15% by 2050, and total depletion within 200-300 years. Our study suggests that (1) anthropogenic drivers on water resources are harsher than projected climatic variability; (2) the estimated water deficit will induce substantial rise in domestic food production's costs, causing higher dependency on food imports; and (3) projected water deficits will most strongly impact the nations with the lowest GDPP, namely Egypt, Yemen and Libya.

  11. Relationships of solar radiation and vapour pressure deficit with photosynthesis and water relations in dry-land pigeon pea

    International Nuclear Information System (INIS)

    Subramanian, V.B.; Venkateswarlu, S.; Maheswari, M.; Sankar, G.R.M.

    1994-01-01

    A study was undertaken to compare the relationships of photosynthetically active radiation (PAR) and vapour pressure deficit (VPD) with carbon assimilation and water relations of dry-land pigeon pea at the vegetative and reproductive phases. Photosynthetic rate (Pn), transpiration rate (T), leaf water potential (wL), and stomatal conductance (gs) were measured at 7- to 10-day intervals from 1 month after seedling until a fortnight before harvest during two seasons. Generally, Pn, T, and gs were higher and wL was lower during the reproductive than during the vegetative phase. At high PAR and VPD, Pn, T, wL, and gs decreased. The decrease in the T at high PAR was smaller during the reproductive phase. Growth of dry-land pigeon pea was affected not only during periods of water stress which was associated with high PAR and high VPD but also under conditions of favourable plant water status which were associated with less than optimal levels of PAR. It also showed transpiration efficiency (TE) was lower during the pod-filling than during the vegetative phase, when PAR was optimum

  12. Developmentally Stable Whole-Brain Volume Reductions and Developmentally Sensitive Caudate and Putamen Volume Alterations in Those With Attention-Deficit/Hyperactivity Disorder and Their Unaffected Siblings

    NARCIS (Netherlands)

    Greven, Corina U.; Bralten, Janita; Mennes, Maarten; O'Dwyer, Laurence; van Hulzen, Kimm J. E.; Rommelse, Nanda; Schweren, Lizanne J. S.; Hoekstra, Pieter J.; Hartman, Catharina A.; Heslenfeld, Dirk; Oosterlaan, Jaap; Faraone, Stephen V.; Franke, Barbara; Zwiers, Marcel P.; Arias-Vasquez, Alejandro; Buitelaar, Jan K.

    IMPORTANCE Attention-deficit/hyperactivity disorder (ADHD) is a heritable neurodevelopmental disorder. It has been linked to reductions in total brain volume and subcortical abnormalities. However, owing to heterogeneity within and between studies and limited sample sizes, findings on the

  13. Can deficit irrigation techniques be used to enhance phosphorus and water use efficiency and benefit crop yields?

    Science.gov (United States)

    Wright, Hannah R.; Dodd, Ian C.; Blackwell, Martin S. A.; Surridge, Ben W. J.

    2015-04-01

    Soil drying and rewetting (DRW) affects the forms and availability of phosphorus (P). Water soluble P has been reported to increase 1.8- to 19-fold after air-drying with the majority of the increase (56-100%) attributable to organic P. Similarly, in two contrasting soil types DRW increased concentrations of total P and reactive P in leachate, likely due to enhanced P mineralisation and physiochemical processes causing detachment of soil colloids, with faster rewetting rates related to higher concentrations of P. The intensity of drying as well as the rate of rewetting influences organic and inorganic P cycling. How these dynamics are driven by soil water status, and impact crop P acquisition and growth, remains unclear. Improving P and water use efficiencies and crop yields is globally important as both P and water resources become increasingly scarce, whilst demand for food increases. Irrigation supply below the water requirement for full crop evapotranspiration is employed by agricultural practitioners where water supply is limited. Regulated deficit irrigation describes the scheduling of water supply to correspond to the times of highest crop demand. Alternate wetting and drying (AWD) is applied in lowland irrigated rice production to avoid flooding at certain times of crop development, and has benefited P nutrition and yields. This research aims to optimise the benefits of P availability and uptake achieved by DRW by guiding deficit irrigation management strategies. Further determination of underlying processes driving P cycling at fluctuating soil moisture status is required. Presented here is a summary of the literature on DRW effects on soil P availability and plant P uptake and partitioning, in a range of soil types and cropping systems, with emphasis on alternate wetting and drying irrigation (AWD) compared to continuous flooding in lowland irrigated rice production. Soil water contents and matric potentials, and effects on P dynamics, are highly variable

  14. The impact of synapsin III gene on the neurometabolite level alterations after single-dose methylphenidate in attention-deficit hyperactivity disorder patients

    Directory of Open Access Journals (Sweden)

    Başay Ö

    2016-05-01

    Full Text Available Ömer Başay,1 Burge Kabukcu Basay,1 Huseyin Alacam,2 Onder Ozturk,1 Ahmet Buber,1 Senay Gorucu Yilmaz,3 Yılmaz Kıroğlu,4 Mehmet Emin Erdal,5 Hasan Herken2 1Department of Child and Adolescent Psychiatry, Faculty of Medicine, Pamukkale University, Denizli, 2Department of Psychiatry, Faculty of Medicine, Pamukkale University, Denizli, 3Department of Nutrition and Dietetics, Faculty of Health Sciences, Gaziantep University, Gaziantep, 4Department of Radiology, School of Medicine, Pamukkale University, Denizli, 5Department of Medical Biology and Genetics, Faculty of Medicine, Mersin University, Mersin, Turkey Objective: To investigate the neurometabolite level changes according to synapsin III gene rs133945G>A and rs133946C>G polymorphisms by using magnetic resonance spectroscopy (MRS in patients with attention-deficit hyperactivity disorder (ADHD.Methods: Fifty-seven adults diagnosed with ADHD were recruited for the study. The participants were examined by single-voxel 1H MRS when medication naïve and 30 minutes after oral administration of 10 mg methylphenidate (Mph. Those who had been on a stimulant discontinued the medication 48 hours before MRS imaging. Spectra were taken from the anterior cingulate cortex, dorsolateral prefrontal cortex, striatum, and cerebellum, and N-acetylaspartate (NAA, choline, and creatine levels were examined. For genotyping of the synapsin III gene polymorphisms, DNA was isolated from peripheral blood leukocytes. The effects of age, sex, and ADHD subtypes were controlled in the analyses.Results: After a single dose of Mph, choline levels increased significantly in the striatum of rs133945G>A polymorphism-GG genotypes (P=0.020 and NAA levels rose in the anterior cingulate cortex of rs133946C>G polymorphism-CG genotypes (P=0.014. Both rs133945G>A and rs133946C>G polymorphisms were found to statistically significantly affect the alteration of NAA levels in response to Mph in dorsolateral prefrontal cortex with

  15. Farm level optimal water management : assistant for irrigation under deficit (FLOW-AID)

    NARCIS (Netherlands)

    Balendonck, J.; Stanghellini, C.; Hemming, J.; Kempkes, F.L.K.; Tuijl, van B.A.J.

    2008-01-01

    FLOW-AID is an on-going 6th Framework European project (2006-2009) with the objective to contribute to sustainable irrigated agriculture by developing an irrigation management system that can be used for crop production in cases with limited water supply and marginal water quality. The project

  16. WATER DEFICIT ENSURES THE PHOTOCHEMICAL EFFICIENCY OF Copaifera langsdorffii Desf1

    Directory of Open Access Journals (Sweden)

    Angélica Lino Rodrigues

    2017-02-01

    Full Text Available ABSTRACT The intensity and frequency of drought periods has increased according to climate change predictions. The fast overcome and recovery are important adaptive features for plant species found in regions presenting water shortage periods. Copaifera langsdorffii is a neotropical species that has developed leaves presenting physiological mechanisms and morphological adaptations that allow its survival under seasonal water stress. We aimed in this work to observe substantial physiological responses for water saving and damage representative to the photochemical reaction after exposed plants to water stress and to subsequent recovery. We found in plants mechanisms to control water loss through the lower stomatal conductance, even after rehydration. It goes against the rapid recovery of leaves, indicated by the relative water content values restored to previously unstressed plants. Stomatal conductance was the only variable presenting high plasticity index. In photochemical activity, the species presented higher photochemical quenching, electron transport rate and effective quantum yield of photosystem II when they were subjected to rehydration after water stress period. Our results suggest that C. langsdorffii presented rapid rehydration and higher photochemical efficiency even after water restriction. These data demonstrate that this species can be used as a model for physiological studies due to the adjustment developed in response to different environmental schemes.

  17. Stover removal effects on seasonal soil water availability under full and deficit irrigation

    Science.gov (United States)

    Removing corn (Zea mays L.) stover for livestock feed or bioenergy feedstock may impact water availability in the soil profile to support crop growth. The role of stover in affecting soil profile water availability will depend on annual rainfall inputs as well as irrigation level. To assess how res...

  18. [Influence of water deficit and supplemental irrigation on nitrogen uptake by winter wheat and nitrogen residual in soil].

    Science.gov (United States)

    Wang, Zhaohui; Wang, Bing; Li, Shengxiu

    2004-08-01

    Pot experiment in greenhouse showed that water deficit at all growth stages and supplemental irrigation at tillering stage significantly decreased the nitrogen uptake by winter wheat and increased the mineral N residual (79.8-113.7 mg x kg(-1)) in soil. Supplemental irrigation at over-wintering, jointing or filling stage significantly increased the nitrogen uptake by plant and decreased the nitrogen residual (47.2-60.3 mg x kg(-1)) in soil. But, the increase of nitrogen uptake caused by supplemental irrigation did not always mean a high magnitude of efficient use of nitrogen by plants. Supplemental irrigation at over-wintering stage didn't induce any significant change in nitrogen content of grain, irrigation at filling stage increased the nitrogen content by 20.9%, and doing this at jointing stage decreased the nitrogen content by 19.6%, as compared to the control.

  19. Implications of high-temperature events and water deficits on protein profiles in wheat (Triticum aestivum L. cv. Vinjett) grain

    DEFF Research Database (Denmark)

    Yang, Fen; Jørgensen, Anders Dysted; Li, Huawei

    2011-01-01

    of interaction of water deficits and/or a high-temperature event (32 degrees C) during vegetative growth (terminal spikelet) with either of these stress events applied during generative growth (anthesis) in wheat. Influence of combinations of stress on protein fractions (albumins, globulins, gliadins...... and glutenins) in grains and stress-induced changes on the albumin and gliadin proteomes were investigated by 2-DE and MS. The synthesis of individual protein fractions was shown to be affected by both the type and time of the applied stresses. Identified drought or high-temperature-responsive proteins included...... proteins involved in primary metabolism, storage and stress response such as late embryogenesis abundant proteins, peroxiredoxins and alpha-amylase/trypsin inhibitors. Several proteins, e.g. heat shock protein and 14-3-3 protein changed in abundance only under multiple high temperatures....

  20. Ecofisiologia de plantas jovens de mogno-africano submetidas a deficit hídrico e reidratação Ecophysiology of young African mahogany plants subjected to water deficit and rewetting

    Directory of Open Access Journals (Sweden)

    Marcos Paulo Ferreira de Albuquerque

    2013-01-01

    Full Text Available O objetivo deste trabalho foi avaliar a capacidade de plantas jovens de mogno-africano (Khaya ivorensis em recuperar seu status hídrico e trocas gasosas após período de deficit hídrico. Plantas com aproximadamente 315 dias, irrigadas (controle e não irrigadas, foram avaliadas aos 14 dias da suspensão da irrigação e após um, três e sete dias da retomada da irrigação (reidratação. No dia 14, o potencial hídrico foliar de antemanhã (Ψam das plantas estressadas foi reduzido a -2,66 MPa. Com a restrição hídrica, foram observadas reduções significativas no conteúdo relativo de água na antemanhã (redução de 32%, na taxa de assimilação líquida de CO2 (90%, na condutância estomática (95%, na transpiração (93% e na razão entre concentração intercelular e ambiental de CO2 (37%. Durante a reidratação, o status hídrico das plantas estressadas foi restabelecido após três dias. As trocas gasosas também se restabeleceram, mas de forma mais lenta que o status hídrico. Sob deficit hídrico, a concentração de prolina aumentou e a de carboidratos solúveis totais diminuiu. Plantas jovens de mogno-africano são tolerantes ao deficit hídrico moderado.The objective of this work was to evaluate the capacity of young plants of African mahogany (Khaya ivorensis to recover their water status and gas exchange after water deficit. Plants with approximately 315 days, irrigated (control and non-irrigated, were evaluated after water was withheld for 14 days, and after one, three, and seven days of irrigation resumption (rehydration. On day 14, the predawn leaf water potential (Ψam of stressed plants was reduced to -2.66 MPa. With water deficit, significant decreases were observed in predawn relative water content (32% reduction, in net assimilation rate of CO2 (90%, in stomatal conductance (95%, in transpiration (93%, and in intercellular to ambient ratio of CO2 concentration (37%. During rehydration, the water status of stressed

  1. Approximate Entropy as a measure of complexity in sap flow temporal dynamics of two tropical tree species under water deficit

    Directory of Open Access Journals (Sweden)

    Gustavo M. Souza

    2004-09-01

    Full Text Available Approximate Entropy (ApEn, a model-independent statistics to quantify serial irregularities, was used to evaluate changes in sap flow temporal dynamics of two tropical species of trees subjected to water deficit. Water deficit induced a decrease in sap flow of G. ulmifolia, whereas C. legalis held stable their sap flow levels. Slight increases in time series complexity were observed in both species under drought condition. This study showed that ApEn could be used as a helpful tool to assess slight changes in temporal dynamics of physiological data, and to uncover some patterns of plant physiological responses to environmental stimuli.Entropia Aproximada (ApEn, um modelo estatístico independente para quantificar irregularidade em séries temporais, foi utilizada para avaliar alterações na dinâmica temporal do fluxo de seiva em duas espécies arbóreas tropicais submetidas à deficiência hídrica. A deficiência hídrica induziu uma grande redução no fluxo de seiva em G. ulmifolia, enquanto que na espécie C. legalis manteve-se estável. A complexidade das séries temporais foi levemente aumentada sob deficiência hídrica. O estudo mostrou que ApEn pode ser usada como um método para detectar pequenas alterações na dinâmica temporal de dados fisiológicos, e revelar alguns padrões de respostas fisiológicas a estímulos ambientais.

  2. Climate change uncertainty and risk assessment in Iran during twenty-first century: evapotranspiration and green water deficit analysis

    Science.gov (United States)

    Karandish, Fatemeh; Mousavi, Seyed-Saeed

    2018-01-01

    For a 120-year period, the projected effects of climate change on annual, seasonal, and monthly potential evapotranspiration (ETo) and green water deficit (GWD) were analyzed involving the associated uncertainties for five climatic zones of Iran. Analysis was carried out using data obtained from 15 general circulation models (GCMs) under three SRES scenarios of A1B, A2, and B1 which were downscaled using LARS-WG for 52 synoptic stations up to 2100. The majority of GCMs as well as the median of the ensemble for each scenario project a positive change in both ETo and GWD. A total of 5.8-19.8 % increase in annual ETo, drier than normal wet seasons, as well as 2.3-56.4 % increase in ETo during December-March period well represent a probable increase in the hydrological water requirement in Iran under global warming. Regarding GWD, the country will experience more arid years requiring 113.7 × 103-576.8 × 103 Mm3 more water to supply annual atmospheric water demand. Semi-arid and Mediterranean regions, principal agricultural producer areas of Iran, will be the most vulnerable part of the country due to 1-38.6 % increase in annual GWD under climate change. In addition, water scarcity for irrigated agriculture will enhance in all climatic zones due to 0.9-41 % increase GWD in June-August. However, rain-fed agriculture might be less affected in the hyper-humid and Mediterranean regions because of 1.1-105.3 % reduction in GWD during wet season. Nevertheless, uncertainty analysis revealed that given results for monthly timescale as well as those for times and regions with lower ETo will be the most uncertain. Based on the results, suitable adaptation solutions are highly required to be undertaken to relieve the extra pressure on the decreased blue water resources in the future.

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

    OpenAIRE

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

    2015-01-01

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

  4. CASE STUDY: Jordan — Dealing with the water deficit in Jordan ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2010-12-20

    Dec 20, 2010 ... So researchers in Jordan found a way to reuse household wastewater ... is using more water than can be replenished by rainfall and other natural sources. ... providing training in system maintenance and irrigation techniques.

  5. Dealing with water deficit in Atta ant colonies: large ants scout for water while small ants transport it

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Da-Silva

    2012-07-01

    Leafcutter ants (Atta sexdens rubropilosa (Forel 1908 have an elaborate social organization, complete with caste divisions. Activities carried out by specialist groups contribute to the overall success and survival of the colony when it is confronted with environmental challenges such as dehydration. Ants detect variations in humidity inside the nest and react by activating several types of behavior that enhance water uptake and decrease water loss, but it is not clear whether or not a single caste collects water regardless of the cost of bringing this resource back to the colony. Accordingly, we investigated water collection activities in three colonies of Atta sexdens rubropilosa experimentally exposed to water stress. Specifically, we analyzed whether or not the same ant caste foraged for water, regardless of the absolute energetic cost (distance of transporting this resource back to the colony. Our experimental design offered water sources at 0 m, 1 m and 10 m from the nest. We studied the body size of ants near the water sources from the initial offer of water (time  =  0 to 120 min, and tested for specialization. We observed a reduction in the average size and variance of ants that corroborated the specialization hypothesis. Although the temporal course of specialization changed with distance, the final outcome was similar among distances. Thus, we conclude that, for this species, a specialist (our use of the word “specialist” does not mean exclusive task force is responsible for collecting water, regardless of the cost of transporting water back to the colony.

  6. Stomatal closure of Pelargonium × hortorum in response to soil water deficit is associated with decreased leaf water potential only under rapid soil drying.

    Science.gov (United States)

    Boyle, Richard K A; McAinsh, Martin; Dodd, Ian C

    2016-01-01

    Soil water deficits applied at different rates and for different durations can decrease both stomatal conductance (gs ) and leaf water potential (Ψleaf ). Understanding the physiological mechanisms regulating these responses is important in sustainable irrigation scheduling. Glasshouse-grown, containerized Pelargonium × hortorum BullsEye plants were irrigated either daily at various fractions of plant evapotranspiration (100, 75 and 50% ET) for 20 days or irrigation was withheld for 4 days. Xylem sap was collected and gs and Ψleaf were measured on days 15 and 20, and on days 16-19 for the respective treatments. Xylem sap pH and NO3 (-) and Ca(2+) concentrations did not differ between irrigation treatments. Xylem abscisic acid (ABA) concentrations ([ABA]xyl ) increased within 24 h of irrigation being withheld whilst gs and Ψleaf decreased. Supplying irrigation at a fraction of daily ET produced a similar relationship between [ABA]xyl and gs , but did not change Ψleaf . Treatment differences occurred independently of whether Ψleaf was measured in whole leaves with a pressure chamber, or in the lamina with a thermocouple psychrometer. Plants that were irrigated daily showed lower [ABA]xyl than plants from which irrigation was withheld, even at comparable soil moisture content. This implies that regular re-watering attenuates ABA signaling due to maintenance of soil moisture in the upper soil levels. Crucially, detached leaves supplied with synthetic ABA showed a similar relationship between [ABA]xyl and gs as intact plants, suggesting that stomatal closure of P. hortorum in response to soil water deficit is primarily an ABA-induced response, independent of changes in Ψleaf . © 2015 Scandinavian Plant Physiology Society.

  7. Differential Responses of Water Uptake Pathways and Expression of Two Aquaporin Genes to Water-Deficit in Rice Seedlings of Two Genotypes

    Directory of Open Access Journals (Sweden)

    Xu Ai-hua

    2017-07-01

    Full Text Available Water-deficit (WD is a major abiotic stress constraining crop productivity worldwide. Zhenshan 97 is a drought-susceptible rice genotype, while IRAT109 is a drought-resistant one. However, the physiological basis of the difference remains unclear. These two genotypes had similar total water uptake rates under both WD and well-watered (WW conditions, and their water uptake rates under WD were significantly decreased compared with those under WW. However, the water uptake rate via the cell-to-cell pathway was significantly increased in Zhenshan 97 but decreased in IRAT109 under WD, whereas the opposite trends were observed through the apoplastic pathway. These results indicated that the stress responses and relative contributions of these two water uptake pathways were associated with rice genotype under WD. The expression levels of OsPIP2;4 and OsPIP2;5 genes were significantly higher in roots of Zhenshan 97 than in IRAT109 under the two conditions. OsPIP2;4 expression in roots was significantly up-regulated under WD, while OsPIP2;5 expression showed no significant change. These results suggest that the expression levels of OsPIP2;4 and OsPIP2;5 in rice are dependent on genotype and water availability. Compared with Zhenshan 97, IRAT109 had a higher root dry weight, water uptake rate and xylem sap flow rate, and lower leaf water potential and root porosity under WD, which might be responsible for the drought resistance in IRAT109.

  8. Effects of progressive soil water deficit on growth, and physiological and biochemical responses of populus euphratica in arid area: a case study in China

    International Nuclear Information System (INIS)

    Yang, Y.; Chen, Y.; Li, W.; Zhu, C.

    2015-01-01

    The aim of this study was to investigate the responses of Populus euphratica seedlings under a short-term soil water deficit. To mimic natural conditions in which drought stress develops gradually, stress was imposed by subjecting plants to a gradual decrease of soil water content for a period of 21 d. We studied growth, physiological and biochemical responses to progressive soil water deficit of potted Populus euphratica seedlings at outdoors. Results showed that, in 6 d of water withholding, the soil moisture content decreased to a slight drought stress level, and it reached a severe drought stress level after 15 d of water withholding in July. In the process of soil water declining from saturated to severe drought levels, the increasing soil water deficit resulted in decreases in the height, stem base diameter, number of lateral branches. Leaf predawn water potential decreased after 15 d of withholding irrigation. After 21 d of withholding irrigation, actual photochemical efficiency of photosystem II (PSII) in light-adapted leaves and photochemical quenching coefficient decreased, respectively; the peroxidase activity, the content of chlorophyll a and chlorophyll b decreased. There were no significant changes in proline, malondialdehyde content, chlorophyll a/b value and superoxide dismutase activity. (author)

  9. Silicon improves seed germination and alleviates oxidative stress of bud seedlings in tomato under water deficit stress.

    Science.gov (United States)

    Shi, Yu; Zhang, Yi; Yao, Hejin; Wu, Jiawen; Sun, Hao; Gong, Haijun

    2014-05-01

    The beneficial effects of silicon on plant growth and development under drought have been widely reported. However, little information is available on the effects of silicon on seed germination under drought. In this work, the effects of exogenous silicon (0.5 mM) on the seed germination and tolerance performance of tomato (Solanum lycopersicum L.) bud seedlings under water deficit stress simulated by 10% (w/v) polyethylene glycol (PEG-6000) were investigated in four cultivars ('Jinpengchaoguan', 'Zhongza No.9', 'Houpi L402' and 'Oubao318'). The results showed that the seed germination percentage was notably decreased in the four cultivars under water stress, and it was significantly improved by added silicon. Compared with the non-silicon treatment, silicon addition increased the activities of superoxide dismutase (SOD) and catalase (CAT), and decreased the production of superoxide anion (O2·) and hydrogen peroxide (H2O2) in the radicles of bud seedlings under water stress. Addition of silicon decreased the total phenol concentrations in radicles under water stress, which might contribute to the decrease of peroxidase (POD) activity, as observed in the in vivo and in vitro experiments. The decrease of POD activity might contribute to a less accumulation of hydroxyl radical (·OH) under water stress. Silicon addition also decreased the concentrations of malondialdehyde (MDA) in the radicles under stress, indicating decreased lipid peroxidation. These results suggest that exogenous silicon could improve seed germination and alleviate oxidative stress to bud seedling of tomato by enhancing antioxidant defense. The positive effects of silicon observed in a silicon-excluder also suggest the active involvement of silicon in biochemical processes in plants. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  10. Gravimetric phenotyping of whole plant transpiration responses to atmospheric vapour pressure deficit identifies genotypic variation in water use efficiency.

    Science.gov (United States)

    Ryan, Annette C; Dodd, Ian C; Rothwell, Shane A; Jones, Ros; Tardieu, Francois; Draye, Xavier; Davies, William J

    2016-10-01

    There is increasing interest in rapidly identifying genotypes with improved water use efficiency, exemplified by the development of whole plant phenotyping platforms that automatically measure plant growth and water use. Transpirational responses to atmospheric vapour pressure deficit (VPD) and whole plant water use efficiency (WUE, defined as the accumulation of above ground biomass per unit of water used) were measured in 100 maize (Zea mays L.) genotypes. Using a glasshouse based phenotyping platform with naturally varying VPD (1.5-3.8kPa), a 2-fold variation in WUE was identified in well-watered plants. Regression analysis of transpiration versus VPD under these conditions, and subsequent whole plant gas exchange at imposed VPDs (0.8-3.4kPa) showed identical responses in specific genotypes. Genotype response of transpiration versus VPD fell into two categories: 1) a linear increase in transpiration rate with VPD with low (high WUE) or high (low WUE) transpiration rate at all VPDs, 2) a non-linear response with a pronounced change point at low VPD (high WUE) or high VPD (low WUE). In the latter group, high WUE genotypes required a significantly lower VPD before transpiration was restricted, and had a significantly lower rate of transpiration in response to VPD after this point, when compared to low WUE genotypes. Change point values were significantly positively correlated with stomatal sensitivity to VPD. A change point in stomatal response to VPD may explain why some genotypes show contradictory WUE rankings according to whether they are measured under glasshouse or field conditions. Furthermore, this novel use of a high throughput phenotyping platform successfully reproduced the gas exchange responses of individuals measured in whole plant chambers, accelerating the identification of plants with high WUE. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Transpiration response of upland rice to water deficit changed by different levels of eucalyptus biochar

    Directory of Open Access Journals (Sweden)

    Rogério Gomes Pereira

    2012-05-01

    Full Text Available The objective of this work was to evaluate the effect of eucalyptus biochar on the transpiration rate of upland rice 'BRSMG Curinga' as an alternative means to decrease the effect of water stress on plant growth and development. Two-pot experiments were carried out using a completely randomized block design, in a split-plot arrangement, with six replicates. Main plots were water stress (WS and no-water stress (NWS, and the subplots were biochar doses at 0, 6, 12 and 24% in growing medium (sand. Total transpirable soil water (TTSW, the p factor - defined as the average fraction of TTSW which can be depleted from the root zone before water stress limits growth -, and the normalized transpiration rate (NTR were determined. Biochar addition increased TTSW and the p factor, and reduced NTR. Consequently, biochar addition was able to change the moisture threshold (p factor of the growing medium, up to 12% maximum concentration, delaying the point where transpiration declines and affects yield.

  12. Growth Of New Alfalfa And Cocksfoot Shoot S During Water-Deficit And Irrigation .2. Modeling

    International Nuclear Information System (INIS)

    Duru, M.; Langlet, A.

    1995-01-01

    Eight regrowths of alfalfa and thirteen of cocksfoot were compared with and without irrigation and with two levels of nitrogen supply (cocksfoot). Aerial biomass was modellized according to PARa. Following a water shortage, the efficiency of radiation intercepted decreased more frequently than the efficiency of the conversion of radiation in biomass for cocksfoot, but the contrary was observed for alfalfa. The decrease in PARa resulted from the direct effect of water shortage, but also from indirect (low value of herbage nitrogen level) and deferred (after-effect as residual leaf area index) effects [it

  13. Shifting species interactions in terrestrial dryland ecosystems under altered water availability and climate change

    Science.gov (United States)

    McCluney, Kevin E.; Belnap, Jayne; Collins, Scott L.; González, Angélica L.; Hagen, Elizabeth M.; Holland, J. Nathaniel; Kotler, Burt P.; Maestre, Fernando T.; Smith, Stanley D.; Wolf, Blair O.

    2012-01-01

    Species interactions play key roles in linking the responses of populations, communities, and ecosystems to environmental change. For instance, species interactions are an important determinant of the complexity of changes in trophic biomass with variation in resources. Water resources are a major driver of terrestrial ecology and climate change is expected to greatly alter the distribution of this critical resource. While previous studies have documented strong effects of global environmental change on species interactions in general, responses can vary from region to region. Dryland ecosystems occupy more than one-third of the Earth's land mass, are greatly affected by changes in water availability, and are predicted to be hotspots of climate change. Thus, it is imperative to understand the effects of environmental change on these globally significant ecosystems. Here, we review studies of the responses of population-level plant-plant, plant-herbivore, and predator-prey interactions to changes in water availability in dryland environments in order to develop new hypotheses and predictions to guide future research. To help explain patterns of interaction outcomes, we developed a conceptual model that views interaction outcomes as shifting between (1) competition and facilitation (plant-plant), (2) herbivory, neutralism, or mutualism (plant-herbivore), or (3) neutralism and predation (predator-prey), as water availability crosses physiological, behavioural, or population-density thresholds. We link our conceptual model to hypothetical scenarios of current and future water availability to make testable predictions about the influence of changes in water availability on species interactions. We also examine potential implications of our conceptual model for the relative importance of top-down effects and the linearity of patterns of change in trophic biomass with changes in water availability. Finally, we highlight key research needs and some possible broader impacts

  14. Effects of soil water deficits on three genotypes of potted Campanula medium plants during bud formation stage

    DEFF Research Database (Denmark)

    Mao, Hongyu; Sun, Yanqi; Müller, Renate

    2014-01-01

    Potted ornamental plants are often exposed to drought stress during shipping and retailing, which decreases the value and postharvest quality. Thus, selection of genotypes which can better withstand soil water deficits is essential for sustainable production. Here, the response of three genotypes...

  15. Effect of the organic matter and soil water deficit on the castor bean inflorescences emission

    Energy Technology Data Exchange (ETDEWEB)

    Lacerda, Rogerio Dantas de; Araujo, Ester Luiz de; Nascimento, Elka Costa Santos; Barros Junior, Genival [Universidade Federal de Campina Grande (UFCG), PB (Brazil); Guerra, Hugo O. Carvallo; Chaves, Lucia Helena G. [Universidade Federal de Campina Grande (UAEAg/UFCG), PB (Brazil). Unidade Academica de Engenharia Agricola

    2008-07-01

    The castor bean culture has become important due to the several applications of its oil, which constitutes one of the best row materials for biodiesel manufacturing, and the base for several other industrial products. The objective of the present work was to study the effect of different soil water and soil organic matter on the castor bean inflorescence emission. The experiment was conducted from April to August 2006 under Greenhouse conditions using a randomized block 2x4 factorial design with two soil organic mater content (5.0 g.kg{sup -1} e 25.0 g.kg{sup -1}), four levels of available water (100, 90, 80 e 70% ) and three replicates. For this, 24 plastic containers, 75 kg capacity, were used on which was grown one plant 120 days after the seedling. When flowering occurred it was measured the number, the time required for the emission and the height of the emissions. The results were analyzed statistically; for the qualitative factor (with and without organic matter) the treatment means were compared through the Tukey test. For the quantitative ones (water levels) regressions were used. The time for the emission of the inflorescences was affected significantly by the organic matter and the available soil water content for plants. The number of inflorescences was affected positively by both treatments. (author)

  16. Influence of the organic matter and soil water deficit on the castor bean absolute growth rate

    Energy Technology Data Exchange (ETDEWEB)

    Lacerda, Rogerio Dantas de; Guerra, Hugo O. Carvallo; Chaves, Lucia Helena G. [Universidade Federal de Campina Grande (UAEAg/UFCG), PB (Brazil). Unidade Academica de Engenharia Agricola; Araujo, Ester Luiz de; Nascimento, Elka Costa Santos; Barros Junior, Genival [Universidade Federal de Campina Grande (UFCG), PB (Brazil)

    2008-07-01

    Even when under low precipitations conditions, the castor bean production decrease, it constitutes a very good alternative. It has an elevated economical importance, because from the plant it is used their leaves, stem and seeds. From the stem it is obtained cellulose for the paper industry, from the leaves textile products and from the seeds oil and tort. The oil is the only glycerin soluble in alcohol and the base for several industrial products such as the biodiesel. The objective of the present work was to study the effect of different soil water and soil organic matter on the castor bean, BRS 188 cultivar rate growth. The experiment was conducted from April to August 2006 under greenhouse conditions using a randomized block 2x4 factorial design with two soil organic mater content (5.0 g.kg{sup -1} e 25.0 g.kg{sup -1}), four levels of available water (100, 90, 80 e 70% ) and three replicates. For this, 24 plastic containers, 75 kg capacity, were used on which was grown one plant 120 days after the seedling. At regular intervals the plant height was measured and the results analyzed statistically. For the qualitative treatments (with and without organic matter) the treatment means were compared through the Tukey test. For the quantitative ones (water levels) regressions were used. It was observed that both, organic matter and available water for plants proportionated benefit effects to the growth rate of the plant. (author)

  17. The effect of water saturation deficit on the volume of intercellular space in laeves

    Directory of Open Access Journals (Sweden)

    J. Czerski

    2015-01-01

    Full Text Available The volume of intercellular spaces in leaves at various stages of water saturation was determined by method of Czerski (1964, 1968. The investigation were performed with the following plant species: Vicia faba L., Nicotiana tabacum L. var. rustica, Solarium tuberosum L. var. Flisak, Helichrysum bracteatum Wild., Bmssica napus L. var. oleifera, Beta vulgaris L. var. saccharifera.

  18. Seasonal scale water deficit forecasting in Africa and the Middle East using NASA's Land Information System (LIS)

    Science.gov (United States)

    Shukla, Shraddhanand; Arsenault, Kristi R.; Getirana, Augusto; Kumar, Sujay V.; Roningen, Jeanne; Zaitchik, Ben; McNally, Amy; Koster, Randal D.; Peters-Lidard, Christa

    2017-04-01

    Drought and water scarcity are among the important issues facing several regions within Africa and the Middle East. A seamless and effective monitoring and early warning system is needed by regional/national stakeholders. Such system should support a proactive drought management approach and mitigate the socio-economic losses up to the extent possible. In this presentation, we report on the ongoing development and validation of a seasonal scale water deficit forecasting system based on NASA's Land Information System (LIS) and seasonal climate forecasts. First, our presentation will focus on the implementation and validation of the LIS models used for drought and water availability monitoring in the region. The second part will focus on evaluating drought and water availability forecasts. Finally, details will be provided of our ongoing collaboration with end-user partners in the region (e.g., USAID's Famine Early Warning Systems Network, FEWS NET), on formulating meaningful early warning indicators, effective communication and seamless dissemination of the monitoring and forecasting products through NASA's web-services. The water deficit forecasting system thus far incorporates NOAA's Noah land surface model (LSM), version 3.3, the Variable Infiltration Capacity (VIC) model, version 4.12, NASA GMAO's Catchment LSM, and the Noah Multi-Physics (MP) LSM (the latter two incorporate prognostic water table schemes). In addition, the LSMs' surface and subsurface runoff are routed through the Hydrological Modeling and Analysis Platform (HyMAP) to simulate surface water dynamics. The LSMs are driven by NASA/GMAO's Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2), and the USGS and UCSB Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) daily rainfall dataset. The LIS software framework integrates these forcing datasets and drives the four LSMs and HyMAP. The Land Verification Toolkit (LVT) is used for the evaluation of the

  19. Morphological, physiological and biochemical responses to soil water deficit in seedlings of three populations of wild pear tree (Pyrus boisseriana

    Directory of Open Access Journals (Sweden)

    Zarafshar, M.

    2014-01-01

    Full Text Available Water shortage limits the production of fruit orchards, such as pear, in arid and semi-arid regions. The identification of wild pear germplasm for potential use as rootstock would be valuable for pear cultivation in semi-arid regions. The relative drought tolerance of wild pear germplasm (Pyrus boisseriana from three different populations distributed along an elevational gradient ('semi-arid 1,000', 'semi-wet 1,350' and 'semi-wet 1,600' populations was evaluated in a greenhouse trial. Established container-grown seedlings were exposed to 18 days of simulated drought, or not, followed by a seven day recovery period. Biomass allocation and accumulation, physiological (stomatal conductance, photosynthesis, transpiration, xylem water potential and biochemical parameters (leaf pigments, free proline, malondialdehyde and hydrogen peroxide production were evaluated. Although all populations were able to recover from water shortage, thereby proving to be relatively drought tolerant, some differences between populations were detected for gas exchange parameters, biomass accumulation and proline concentration in favor of the 'semi-arid 1,000' elevation population, which was more drought tolerant. This population showed the most rapid and complete recovery of physiological activity (stomatal conductance and carbon fixation. In addition, all populations showed an increase in carotenoid content in the leaves. Overall, we showed that plants from the 'semi-arid 1,000' elevation had greater tolerance to drought than those from the higher elevations (semi-wet populations. It therefore appears that plants from the 'semi-arid 1,000' elevation represent a promising source of material to be tested as rootstock for commercial scions of pear in field conditions in areas prone to suffer from water deficit.

  20. Forest legacies, climate change, altered disturbance regimes, invasive species and water

    Science.gov (United States)

    Stohlgren, T.; Jarnevich, C.; Kumar, S.

    2007-01-01

    The factors that must be considered in seeking to predict changes in water availability has been examined. These factors are the following: forest legacies including logging, mining, agriculture, grazing, elimination of large carnivores, human-caused wildfire, and pollution; climate change and stream flow; altered disturbances such as frequency intensity and pattern of wildfires and insect outbreaks as well as flood control; lastly, invasive species like forest pests and pathogens. An integrated approach quantifying the current and past condition trends can be combined with spatial and temporal modeling to develop future change in forest structures and water supply. The key is a combination of geographic information system technologies with climate and land use scenarios, while preventing and minimizing the effects of harmful invasive species.

  1. Effect of Water Deficit-Induced at Vegetative and Reproductive Stages on Protein and Oil Content in Soybean Grains

    Directory of Open Access Journals (Sweden)

    Liliane M. Mertz-Henning

    2017-12-01

    Full Text Available Soybean is one of the most common grain crops worldwide, representing an important protein and oil source. Although genetic variability in the chemical composition of grains is seen in soybean, the mean levels of proteins have remained stagnant or, in some cases, have decreased over time, arousing concern in the agricultural industry. Furthermore, environmental conditions influence the chemical composition of grains. Thus, the present study evaluated the effect of water deficit (WD induced at the vegetative period (vegetative stress (VS and reproductive period (reproductive stress (RS on the protein and oil contents of grains in different soybean genotypes. Yield and its components were evaluated to evaluate the interrelation of these traits. The experiment was completed over three crop seasons under field conditions in Londrina, Paraná (PR, Brazil. WD was induced using rainout shelters and then stress treatments with irrigated and non-irrigated conditions were compared. WD negatively affected yield and its components. All evaluated genotypes showed similar responses for oil and protein contents under different water conditions. Higher protein content and lower oil content were observed in grains under RS. Such a relationship was not equally established under VS. Additionally, negative relationships between protein and oil content and between protein content and yield were confirmed.

  2. Bayesian inference for the genetic control of water deficit tolerance in spring wheat by stochastic search variable selection.

    Science.gov (United States)

    Safari, Parviz; Danyali, Syyedeh Fatemeh; Rahimi, Mehdi

    2018-06-02

    Drought is the main abiotic stress seriously influencing wheat production. Information about the inheritance of drought tolerance is necessary to determine the most appropriate strategy to develop tolerant cultivars and populations. In this study, generation means analysis to identify the genetic effects controlling grain yield inheritance in water deficit and normal conditions was considered as a model selection problem in a Bayesian framework. Stochastic search variable selection (SSVS) was applied to identify the most important genetic effects and the best fitted models using different generations obtained from two crosses applying two water regimes in two growing seasons. The SSVS is used to evaluate the effect of each variable on the dependent variable via posterior variable inclusion probabilities. The model with the highest posterior probability is selected as the best model. In this study, the grain yield was controlled by the main effects (additive and non-additive effects) and epistatic. The results demonstrate that breeding methods such as recurrent selection and subsequent pedigree method and hybrid production can be useful to improve grain yield.

  3. Physiology and transcriptomics of water-deficit stress responses in wheat cultivars TAM 111 and TAM 112.

    Science.gov (United States)

    Reddy, Srirama Krishna; Liu, Shuyu; Rudd, Jackie C; Xue, Qingwu; Payton, Paxton; Finlayson, Scott A; Mahan, James; Akhunova, Alina; Holalu, Srinidhi V; Lu, Nanyan

    2014-09-01

    Hard red winter wheat crops on the U.S. Southern Great Plains often experience moderate to severe drought stress, especially during the grain filling stage, resulting in significant yield losses. Cultivars TAM 111 and TAM 112 are widely cultivated in the region, share parentage and showed superior but distinct adaption mechanisms under water-deficit (WD) conditions. Nevertheless, the physiological and molecular basis of their adaptation remains unknown. A greenhouse study was conducted to understand the differences in the physiological and transcriptomic responses of TAM 111 and TAM 112 to WD stress. Whole-plant data indicated that TAM 112 used more water, produced more biomass and grain yield under WD compared to TAM 111. Leaf-level data at the grain filling stage indicated that TAM 112 had elevated abscisic acid (ABA) content and reduced stomatal conductance and photosynthesis as compared to TAM 111. Sustained WD during the grain filling stage also resulted in greater flag leaf transcriptome changes in TAM 112 than TAM 111. Transcripts associated with photosynthesis, carbohydrate metabolism, phytohormone metabolism, and other dehydration responses were uniquely regulated between cultivars. These results suggested a differential role for ABA in regulating physiological and transcriptomic changes associated with WD stress and potential involvement in the superior adaptation and yield of TAM 112. Copyright © 2014 Elsevier GmbH. All rights reserved.

  4. CHANGES IN LEVELS OF ACTIVITY OF SERINE PROTEASES ACCOMPANY THE EXPOSURE OF COMMON BEAN (PHASEOLUS VULGARIS L. TO WATER DEFICIT

    Directory of Open Access Journals (Sweden)

    M. Budič

    2008-09-01

    Full Text Available A wide variety of proteolytic enzymes exist in plants. On their levels depends protein turnover, a fundamental component in plant development and adaptation to environmental conditions. Cysteine proteases have frequently been reported to be influenced by drought, but only a few serine proteases (SP, among them the trypsin-like enzyme and two aminopeptidases from bean leaves (Bartels and Sunkar, 2005; Hieng et al., 2004. Our starting point was to identify proteolytic activities assigned to SPs that change with drought and then to characterize the corresponding proteases. A quantitative, analytical one-step method was used to separate endopeptidases and aminopeptidases active against a range of substrates in leaf extracts of plants grown in the field (FC. The influence of drought was determined for those of these activities which were confirmed as SPs, based on their inhibition by specific inhibitors. Under water deficit in plants grown under controlled conditions (CC their levels changed in different ways. The levels of SP activities in FC plants, observed during a period of relative drought, were similar to those measured in mildly stressed CC plants. The partial characterisations of some of these SPs will be presented. Our results point to a number of roles for different SPs in the plant response to water stress, which could range from enhanced protein turnover to limited proteolysis at specific sites.

  5. Nitrate reductase and photosynthetic activities of wheat and their relationship with plant productivity under soil water deficit conditions (abstract)

    International Nuclear Information System (INIS)

    Ashraf, M.Y.; Sarwar, G.; Hussain, F.

    2005-01-01

    Experiments were conducted in lysimeters with wheat during two consecutive years. The first year experiment comprised of eight wheat genotypes with four water stress treatments, i.e. normal irrigation, pre-anthesis drought, post-anthesis drought and terminal drought, with four replications. The results showed that yield and yield parameters reduced with the severity of drought in all wheat lines. However, wheat lines Chakwal-86, DS-4 and Barani-83 had comparatively higher yield and yield components than others. The maximum reduction in all parameters was under terminal drought. The difference between pre- and post-anthesis drought was nonsignificant, particularly for grain yield. The second experiment was conducted with four wheat lines: two were tolerant (Chakwal-86 and DS-4) and two susceptible (Pavon and DS-17) under similar environments with same treatments to study the photosynthetic efficiency, nitrogen metabolism and their relationship with plant productivity (yield). The results showed that leaf area, transpiration, dry matter accumulation and nitrate reductase activity were reduced while diffusive resistance and total amino acids increased in all the wheat lines under water deficit conditions. The relationship between yield and leaf area, transpiration, dry matter accumulation and nitrate reductase activity was positive. The overall results showed that wheat lines Chakwal-86 and DS-4 showed better performance than others. (author)

  6. Response of Pearl Millet to nitrogen as affected by water deficit

    OpenAIRE

    Diouf , O.; Brou , Yao Télesphore; Diouf , M.; Sarr , B.; Eyletters , M.; Roy-Macauley , H.; Delhaye , J.

    2004-01-01

    International audience; In the Sahelian zone, low soil N could be as limiting as drought in pearl millet production. Although growth and crop productivity depend on several biochemical reactions in which the nitrogen metabolism plays a great role, there is little information available on how N uptake and key enzymes, nitrate reductase and glutamine synthetase, are affected by nitrogen and water interaction in millet. For this purpose, the millet variety cv. Souna III was grown in the field du...

  7. Effect of water α radiolysis on the spent nuclear fuel UO2 matrix alteration

    International Nuclear Information System (INIS)

    Lucchini, J.F.

    2001-01-01

    In the option of long term storage or direct disposal of nuclear spent fuel, it is essential to study the long-term behaviour of the spent fuel matrix (UO 2 ) in water, in presence of ionizing radiations. This work gives some knowledge elements about the impact of aerated water alpha radiolysis on UO 2 alteration. An original experiment method was used in this study. UO 2 /water interfaces were irradiated by an external He 2+ ions beam. The sequential batch dissolution tests on UO 2 samples were performed in aerated deionized water, before, during and after a-irradiation under high fluxes. A corrosion product, identified as hydrated uranium peroxide, was formed on the UO 2 surface. The uranium release was 3 to 4 orders of magnitude higher under irradiation than out of irradiation. The concentrations of the radiolysis products H 2 O 2 and H 3 O + were affected by the uranium oxide surface. They could not only explain the whole uranium release reached during irradiation in water. Leaching experiments on UO X spent fuel samples (with or without the Zircaloy clad) were also performed, in hot cells. The uranium release was relatively small, and H 2 O 2 was not detected in solution. The rates of uranium release in aerated water during one hour were calculated. They were about mg -1 .m -2 .d -1 for spent fuel and for UO 2 , and about g -1 .m -2 .d -1 for UO 2 irradiated by He 2+ ions. The comparison of the results between the two kinds of experiment shows a difference of the behaviour in water between UO 2 irradiated by He 2+ ions and spent fuel. Some hypothesis are given to explain this difference. (author)

  8. Altered Gravity Simulated by Parabolic Flight and Water Immersion Leads to Decreased Trunk Motion.

    Directory of Open Access Journals (Sweden)

    Peiliang Wang

    Full Text Available Gravity is one of the important environmental factors that influence the physiologies and behaviors of animals and humans, and changes in gravity elicit a variety of physiological and behavioral alterations that include impaired movement coordination, vertigo, spatial disorientation, and perceptual illusions. To elucidate the effects of gravity on human physiology and behavior, we examined changes in wrist and trunk activities and heart rate during parabolic flight and the activity of wrist and trunk in water immersion experiments. Data from 195 person-time parabolas performed by eight subjects revealed that the trunk motion counts decreased by approximately half during ascending legs (hypergravity, relative to the data acquired before the parabolic flights. In contrast, the wrist activity remained unchanged. The results from the water immersion experiments demonstrated that in the underwater condition, both the wrist and trunk activities were significantly decreased but the latter decreased to a much lower level. Together, these data suggest that gravitational alterations can result in differential influences on the motions of the wrist and the trunk. These findings might be important for understanding the degeneration of skeleton and muscular system and performance of astronauts in microgravity.

  9. Altered Gravity Simulated by Parabolic Flight and Water Immersion Leads to Decreased Trunk Motion

    Science.gov (United States)

    Tian, Yu; Li, Fan; Zhang, Shaoyao; Zhang, Lin; Guo, Yaoyu; Liu, Weibo; Wang, Chunhui; Chen, Shanguang; Guo, Jinhu

    2015-01-01

    Gravity is one of the important environmental factors that influence the physiologies and behaviors of animals and humans, and changes in gravity elicit a variety of physiological and behavioral alterations that include impaired movement coordination, vertigo, spatial disorientation, and perceptual illusions. To elucidate the effects of gravity on human physiology and behavior, we examined changes in wrist and trunk activities and heart rate during parabolic flight and the activity of wrist and trunk in water immersion experiments. Data from 195 person-time parabolas performed by eight subjects revealed that the trunk motion counts decreased by approximately half during ascending legs (hypergravity), relative to the data acquired before the parabolic flights. In contrast, the wrist activity remained unchanged. The results from the water immersion experiments demonstrated that in the underwater condition, both the wrist and trunk activities were significantly decreased but the latter decreased to a much lower level. Together, these data suggest that gravitational alterations can result in differential influences on the motions of the wrist and the trunk. These findings might be important for understanding the degeneration of skeleton and muscular system and performance of astronauts in microgravity. PMID:26208253

  10. Three-dimensional geophysical mapping of shallow water saturated altered rocks at Mount Baker, Washington: Implications for slope stability

    Science.gov (United States)

    Finn, Carol A.; Deszcz-Pan, Maryla; Ball, Jessica L.; Bloss, Benjamin J.; Minsley, Burke J.

    2018-05-01

    Water-saturated hydrothermal alteration reduces the strength of volcanic edifices, increasing the potential for catastrophic sector collapses that can lead to far traveled and destructive debris flows. Intense hydrothermal alteration significantly lowers the resistivity and magnetization of volcanic rock and therefore hydrothermally altered rocks can be identified with helicopter electromagnetic and magnetic measurements. Geophysical models constrained by rock properties and geologic mapping show that intensely altered rock is restricted to two small (500 m diameter), >150 m thick regions around Sherman Crater and Dorr Fumarole Field at Mount Baker, Washington. This distribution of alteration contrasts with much thicker and widespread alteration encompassing the summits of Mounts Adams and Rainier prior to the 5600 year old Osceola collapse, which is most likely due to extreme erosion and the limited duration of summit magmatism at Mount Baker. In addition, the models suggest that the upper 300 m of rock contains water which could help to lubricate potential debris flows. Slope stability modeling incorporating the geophysically modeled distribution of alteration and water indicates that the most likely and largest ( 0.1 km3) collapses are from the east side of Sherman Crater. Alteration at Dorr Fumarole Field raises the collapse hazard there, but not significantly because of its lower slope angles. Geochemistry and analogs from other volcanoes suggest a model for the edifice hydrothermal system.

  11. Three-dimensional geophysical mapping of shallow water saturated altered rocks at Mount Baker, Washington: Implications for slope stability

    Science.gov (United States)

    Finn, Carol A.; Deszcz-Pan, Maria; Ball, Jessica L.; Bloss, Benjamin J.; Minsley, Burke J.

    2018-01-01

    Water-saturated hydrothermal alteration reduces the strength of volcanic edifices, increasing the potential for catastrophic sector collapses that can lead to far traveled and destructive debris flows. Intense hydrothermal alteration significantly lowers the resistivity and magnetization of volcanic rock and therefore hydrothermally altered rocks can be identified with helicopter electromagnetic and magnetic measurements. Geophysical models constrained by rock properties and geologic mapping show that intensely altered rock is restricted to two small (500 m diameter), >150 m thick regions around Sherman Crater and Dorr Fumarole Field at Mount Baker, Washington. This distribution of alteration contrasts with much thicker and widespread alteration encompassing the summits of Mounts Adams and Rainier prior to the 5600 year old Osceola collapse, which is most likely due to extreme erosion and the limited duration of summit magmatism at Mount Baker. In addition, the models suggest that the upper ~300 m of rock contains water which could help to lubricate potential debris flows. Slope stability modeling incorporating the geophysically modeled distribution of alteration and water indicates that the most likely and largest (~0.1 km3) collapses are from the east side of Sherman Crater. Alteration at Dorr Fumarole Field raises the collapse hazard there, but not significantly because of its lower slope angles. Geochemistry and analogs from other volcanoes suggest a model for the edifice hydrothermal system.

  12. Wheel running from a juvenile age delays onset of specific motor deficits but does not alter protein aggregate density in a mouse model of Huntington's disease

    Directory of Open Access Journals (Sweden)

    Spires Tara L

    2008-04-01

    Full Text Available Abstract Background Huntington's disease (HD is a neurodegenerative disorder predominantly affecting the cerebral cortex and striatum. Transgenic mice (R6/1 line, expressing a CAG repeat encoding an expanded polyglutamine tract in the N-terminus of the huntingtin protein, closely model HD. We have previously shown that environmental enrichment of these HD mice delays the onset of motor deficits. Furthermore, wheel running initiated in adulthood ameliorates the rear-paw clasping motor sign, but not an accelerating rotarod deficit. Results We have now examined the effects of enhanced physical activity via wheel running, commenced at a juvenile age (4 weeks, with respect to the onset of various behavioral deficits and their neuropathological correlates in R6/1 HD mice. HD mice housed post-weaning with running wheels only, to enhance voluntary physical exercise, have delayed onset of a motor co-ordination deficit on the static horizontal rod, as well as rear-paw clasping, although the accelerating rotarod deficit remains unaffected. Both wheel running and environmental enrichment rescued HD-induced abnormal habituation of locomotor activity and exploratory behavior in the open field. We have found that neither environment enrichment nor wheel running ameliorates the shrinkage of the striatum and anterior cingulate cortex (ACC in HD mice, nor the overall decrease in brain weight, measured at 9 months of age. At this age, the density of ubiquitinated protein aggregates in the striatum and ACC is also not significantly ameliorated by environmental enrichment or wheel running. Conclusion These results indicate that enhanced voluntary physical activity, commenced at an early presymptomatic stage, contributes to the positive effects of environmental enrichment. However, sensory and cognitive stimulation, as well as motor stimulation not associated with running, may constitute major components of the therapeutic benefits associated with enrichment

  13. Studies on 13C isotope discrimination for identifying tree provenances efficient in water use under water deficit conditions in Kenya

    International Nuclear Information System (INIS)

    Nyamai, D.O.; Juma, P.O.

    1996-01-01

    Screening for drought resistance traits was conducted in a semi-arid site in Machakos using 11 provenances of Acacia tortilis, 6 provenances of Prosopis juliflora and 4 provenances of Casuarina equisetifolia. Tolerance to drought was assessed by the 13 C isotope discrimination (Δ) technique as well as by determining the waster use efficiency (WUE). Measurements of dry matter and early growth performance were also taken as indicators of drought resistance. The results showed significant differences in the 13 C Isotope discrimination, water use efficiency and dry matter yields by the different provenances tested. Generally, the results indicated that there were significant linear negative relationships between 13 C discrimination with water use efficiency as well as dry matter yield. The results further showed highly significant positive relationship between dry matter yield and water use efficiency. Acacia tortilis provenances from middle East and neighbouring North Eastern Africa region appear to possess the greatest abilities for drought resistance in comparison with those from sub-saharan Africa as indicated by their 13 C Isotope discrimination levels, dry matter yield and water use efficiency. However, Acacia provenance from Israel had the highest drought resistance trail. Prosopis provenance from Costa Rica and Casuarina from Dakar region in Senegal also emerged as the best provenances in terms of drought tolerance as shown by the 13 C isotope discrimination and dry matter traits. (author). 8 refs, 4 figs, 3 tabs

  14. Blind rats are not profoundly impaired in the reference memory Morris water maze and cannot be clearly discriminated from rats with cognitive deficits in the cued platform task.

    Science.gov (United States)

    Lindner, M D; Plone, M A; Schallert, T; Emerich, D F

    1997-06-01

    The Morris water maze is commonly used to test cognitive function in rodent models of neurological disorders including age-related cognitive deficits. It is often assumed that the most profoundly impaired aged rats may be blind due to retinal degeneration, and it has been reported that animals with visual sensory deficits can be identified based on their performance in a cued platform task. The results of the present study demonstrate that blind rats can perform surprisingly well in the reference memory version of the Morris water maze, and that blind rats cannot be selectively excluded based on performance in the cued platform task since atropine-treated rats also perform poorly in the cued platform task. Future studies may be able to develop screening procedures that help to eliminate subjects with non-cognitive deficits, but the present results do not support the use of the cued platform or straight swim task as screening procedures. Experimenters must be careful to consider the role that visual sensory function and other non-cognitive factors may have in performance of the spatial learning Morris water maze, and also the role that severe cognitive deficits may have in performance of the cued platform task.

  15. Water deficit affects primary metabolism differently in two Lolium multiflorum/Festuca arundinacea introgression forms with a distinct capacity for photosynthesis and membrane regeneration.

    Directory of Open Access Journals (Sweden)

    Dawid Perlikowski

    2016-07-01

    Full Text Available Understanding how plants respond to drought at different levels of cell metabolism is an important aspect of research on the mechanisms involved in stress tolerance. Furthermore, a dissection of drought tolerance into its crucial components by the use of plant introgression forms facilitates to analyze this trait more deeply. The important components of plant drought tolerance are the capacity for photosynthesis under drought conditions, and the ability of cellular membrane regeneration after stress cessation. Two closely related introgression forms of Lolium multiflorum/Festuca arundinacea, differing in the level of photosynthetic capacity during stress, and in the ability to regenerate their cellular membranes after stress cessation, were used as forage grass models in a primary metabolome profiling and in an evaluation of chloroplast 1,6-bisphosphate aldolase accumulation level and activity, during 11 days of water deficit, followed by 10 days of rehydration. It was revealed here that the introgression form, characterized by the ability to regenerate membranes after rehydration, contained higher amounts of proline, melibiose, galactaric acid, myo-inositol and myo-inositol-1-phosphate involved in osmoprotection and stress signaling under drought. Moreover, during the rehydration period, this form also maintained elevated accumulation levels of most the primary metabolites, analyzed here. The other introgression form, characterized by the higher capacity for photosynthesis, revealed a higher accumulation level and activity of chloroplast aldolase under drought conditions, and higher accumulation levels of most photosynthetic products during control and drought periods. The potential impact of the observed metabolic alterations on cellular membrane recovery after stress cessation, and on a photosynthetic capacity under drought conditions in grasses, are discussed.

  16. The effect of water deficit stress and nitrogen fertilizer levels on morphology traits, yield and leaf area index in maize

    International Nuclear Information System (INIS)

    Moosavi, S.G.

    2012-01-01

    In order to study the effect of water deficit stress at different growth stages and N fertilizer levels on morphological traits, yield and yield components of maize cv. Single Cross 704, an experiment was conducted as a split-plot based on a Randomized Complete Block Design with three replications. The main plot included irrigation at four levels (irrigation stop at 10-leaf, tasselling and grain-filling stages and optimum irrigation) and the sub-plot was N fertilizer at three levels (75, 150 and 225 kg N/ha). The results of analysis of variance showed that water-deficit stress and N fertilizer level significantly affected leaf area index at silking stage, ear length, grain number per ear, 1000-grain weight and grain yield. Stem diameter, ear diameter and harvest index were only affected by irrigation treatments and the interaction between irrigation and N level did not significantly affect the studied traits. Means comparison indicated that ear diameter under optimum irrigation was higher than that under the treatments of irrigation stop at 8-leaf, tasselling and grain-filling stages by 29.9, 19.1 and 33.5%, respectively; and ear length was higher than them by 38.1, 28.9 and 25.2%, respectively. Moreover, the highest grain number per ear, 1000-grain weight and grain yield were obtained under optimum irrigation treatment, and irrigation stop at 10-leaf, tasselling and grain-filling stages decreased grain yield by 52.8, 66.4 and 44.9%, respectively; and it decreased grain number/ear by 45.9, 59.3 and 30.1%, respectively. In addition, optimum irrigation treatment with mean 1000-grain weight of 289.2 g was significantly superior over other irrigation stop treatments by 27.6-42.8% and produced the highest leaf area index at silking stage (4.1). Means comparison of traits at different N levels indicated that N level of 225 kg/ha produced the highest ear length (17.82 cm), grain number per ear (401.9), 1000-grain weight (258.8 g), leaf area index at silking stage (4

  17. Nutrients, Trace Elements and Water Deficit in Greek Soils Cultivated with Olive Trees

    Directory of Open Access Journals (Sweden)

    Theodore Karyotis

    2014-11-01

    Full Text Available The studied soils consist of alluvial and/or colluvial deposits  located in the Prefecture of Messinia, Western Peloponnese (Greece. A total number of 263 surface soil layers were selected and analysed for the main properties. Minimum and maximum values and  the distribution of soil properties varied greatly and can be attributed mainly to various fertilization practices adopted by  farmers, inputs of nutrients by irrigation water and differences due to inherent soil conditions. Lower variability was recorded for the parameters pH, Cation Exchange Capacity (CEC, total soil nitrogen (N and soil organic matter (SOM, while coefficients of variation for properties that can be affected easily by human activities such as available phosphorus and micronutrients, are much higher. Minor content for trace elements was observed in the following order:Zinc (Zn>Manganese (Mn>Boron (B>Iron (Fe. During the dry period, irrigation of olive trees is recommended and the appropriate irrigation demands were defined, taking into account rainfall and  water requirements.

  18. Modulating the phenology and yield of camelina sativa L. by varying sowing dates under water deficit stress conditions

    Directory of Open Access Journals (Sweden)

    Ejaz Ahmad Waraich

    2017-05-01

    Full Text Available Camelina (Camelina sativa L. an oilseed crop has emerged as a potential source for biofuels and bio-products. Camelina is an economic crop due to its less requirements of agronomic inputs as compared to other oilseed crops. However, it is direly required to evaluate the adaptability of camelina and characterize its production potential. Therefore, a pot experiment was carried out in rain out shelter at the Department of Agronomy, University of Agriculture, Faisalabad, Pakistan to optimize appropriate sowing date with respect to growth and yield potential of different genotypes of camelina under drought stress. Completely randomized design with factorial arrangements was adopted. Three sowing dates with the difference of 10 days (November 13 th, 23rd and December 03rd, two water regimes (100% FC and 60% FC and two camlena genotypes (611 and 618 were used in this experiment. Results indicated that camelina growth and yield related traits were significantly influenced by difference in sowing dates and water regimes. Maximum leaf area index (LAI, crop growth rate (CGR, leaf area duration (LAD, net assimilation rate (NAR and yield related traits were recorded with early sowing (13th November which was followed by sowing on 23rd November and least values of these variables were recorded in late sowing (December 03rd. Plants grown under water deficit conditions (60% FC showed the decreased values of LAI, CGR, LAD, NAR and yield related attributes as compared to normally irrigated plants (100% FC. However, the response of genotypes of camelina 611 and 618 remained statistically similar to each other.

  19. Bark beetle-induced tree mortality alters stand energy budgets due to water budget changes

    Science.gov (United States)

    Reed, David E.; Ewers, Brent E.; Pendall, Elise; Frank, John; Kelly, Robert

    2018-01-01

    Insect outbreaks are major disturbances that affect a land area similar to that of forest fires across North America. The recent mountain pine bark beetle ( D endroctonus ponderosae) outbreak and its associated blue stain fungi ( Grosmannia clavigera) are impacting water partitioning processes of forests in the Rocky Mountain region as the spatially heterogeneous disturbance spreads across the landscape. Water cycling may dramatically change due to increasing spatial heterogeneity from uneven mortality. Water and energy storage within trees and soils may also decrease, due to hydraulic failure and mortality caused by blue stain fungi followed by shifts in the water budget. This forest disturbance was unique in comparison to fire or timber harvesting because water fluxes were altered before significant structural change occurred to the canopy. We investigated the impacts of bark beetles on lodgepole pine ( Pinus contorta) stand and ecosystem level hydrologic processes and the resulting vertical and horizontal spatial variability in energy storage. Bark beetle-impacted stands had on average 57 % higher soil moisture, 1.5 °C higher soil temperature, and 0.8 °C higher tree bole temperature over four growing seasons compared to unimpacted stands. Seasonal latent heat flux was highly correlated with soil moisture. Thus, high mortality levels led to an increase in ecosystem level Bowen ratio as sensible heat fluxes increased yearly and latent heat fluxes varied with soil moisture levels. Decline in canopy biomass (leaf, stem, and branch) was not seen, but ground-to-atmosphere longwave radiation flux increased, as the ground surface was a larger component of the longwave radiation. Variability in soil, latent, and sensible heat flux and radiation measurements increased during the disturbance. Accounting for stand level variability in water and energy fluxes will provide a method to quantify potential drivers of ecosystem processes and services as well as lead to greater

  20. Water-Deficit Tolerance in Sweet Potato [Ipomoea batatas (L. Lam.] by Foliar Application of Paclobutrazol: Role of Soluble Sugar and Free Proline

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    Suravoot Yooyongwech

    2017-08-01

    Full Text Available The objective of this study was to elevate water deficit tolerance by improving soluble sugar and free proline accumulation, photosynthetic pigment stabilization, photosynthetic abilities, growth performance and storage root yield in sweet potato cv. ‘Tainung 57’ using a foliar application of paclobutrazol (PBZ. The experiment followed a Completely Randomized Block Design with four concentrations of PBZ: 0 (control, 17, 34, and 51 μM before exposure to 47.5% (well irrigation, 32.3% (mild water deficit or 17.5% (severe water deficit soil water content. A sweet potato cultivar, ‘Japanese Yellow’, with water deficit tolerance attributes was the positive check in this study. Total soluble sugar content (sucrose, glucose, and fructose increased by 3.96-folds in ‘Tainung 57’ plants treated with 34 μM PBZ grown under 32.3% soil water content (SWC compared to the untreated plants, adjusting osmotic potential in the leaves and controlling stomatal closure (represented by stomatal conductance and transpiration rate. In addition, under the same treatment, free proline content (2.15 μmol g-1 FW increased by 3.84-folds when exposed to 17.5% SWC. PBZ had an improved effect on leaf size, vine length, photosynthetic pigment stability, chlorophyll fluorescence, and net photosynthetic rate; hence, delaying wilting symptoms and maintaining storage root yield (26.93 g plant-1 at the harvesting stage. A positive relationship between photon yield of PSII (ΦPSII and net photosynthetic rate was demonstrated (r2 = 0.73. The study concludes that soluble sugar and free proline enrichment in PBZ-pretreated plants may play a critical role as major osmoprotectant to control leaf osmotic potential and stomatal closure when plants were subjected to low soil water content, therefore, maintaining the physiological and morphological characters as well as storage root yield.

  1. Water-Deficit Tolerance in Sweet Potato [Ipomoea batatas (L.) Lam.] by Foliar Application of Paclobutrazol: Role of Soluble Sugar and Free Proline.

    Science.gov (United States)

    Yooyongwech, Suravoot; Samphumphuang, Thapanee; Tisarum, Rujira; Theerawitaya, Cattarin; Cha-Um, Suriyan

    2017-01-01

    The objective of this study was to elevate water deficit tolerance by improving soluble sugar and free proline accumulation, photosynthetic pigment stabilization, photosynthetic abilities, growth performance and storage root yield in sweet potato cv. 'Tainung 57' using a foliar application of paclobutrazol (PBZ). The experiment followed a Completely Randomized Block Design with four concentrations of PBZ: 0 (control), 17, 34, and 51 μM before exposure to 47.5% (well irrigation), 32.3% (mild water deficit) or 17.5% (severe water deficit) soil water content. A sweet potato cultivar, 'Japanese Yellow', with water deficit tolerance attributes was the positive check in this study. Total soluble sugar content (sucrose, glucose, and fructose) increased by 3.96-folds in 'Tainung 57' plants treated with 34 μM PBZ grown under 32.3% soil water content (SWC) compared to the untreated plants, adjusting osmotic potential in the leaves and controlling stomatal closure (represented by stomatal conductance and transpiration rate). In addition, under the same treatment, free proline content (2.15 μmol g -1 FW) increased by 3.84-folds when exposed to 17.5% SWC. PBZ had an improved effect on leaf size, vine length, photosynthetic pigment stability, chlorophyll fluorescence, and net photosynthetic rate; hence, delaying wilting symptoms and maintaining storage root yield (26.93 g plant -1 ) at the harvesting stage. A positive relationship between photon yield of PSII (Φ PSII ) and net photosynthetic rate was demonstrated ( r 2 = 0.73). The study concludes that soluble sugar and free proline enrichment in PBZ-pretreated plants may play a critical role as major osmoprotectant to control leaf osmotic potential and stomatal closure when plants were subjected to low soil water content, therefore, maintaining the physiological and morphological characters as well as storage root yield.

  2. In Utero Exposure to a Cardiac Teratogen Causes Reversible Deficits in Postnatal Cardiovascular Function, But Altered Adaptation to the Burden of Pregnancy.

    Science.gov (United States)

    Aasa, Kristiina L; Maciver, Rebecca D; Ramchandani, Shyamlal; Adams, Michael A; Ozolinš, Terence R S

    2015-11-01

    Congenital heart defects (CHD) are the most common birth anomaly and while many resolve spontaneously by 1 year of age, the lifelong burden on survivors is poorly understood. Using a rat model of chemically induced CHD that resolve postnatally, we sought to characterize the postnatal changes in cardiac function, and to investigate whether resolved CHD affects the ability to adapt to the increased the cardiovascular (CV) burden of pregnancy. To generate rats with resolved CHD, pregnant rats were administered distilled water or dimethadione (DMO) [300 mg/kg b.i.d. on gestation day (gd) 9 and 10] and pups delivered naturally. To characterize structural and functional changes in the heart, treated and control offspring were scanned by echocardiography on postnatal day 4, 21, and 10-12 weeks. Radiotelemeters were implanted for continuous monitoring of hemodynamics. Females were mated and scanned by echocardiography on gd12 and gd18 during pregnancy. On gd18, maternal hearts were collected for structural and molecular assessment. Postnatal echocardiography revealed numerous structural and functional differences in treated offspring compared with control; however, these resolved by 10-12 weeks of age. The CV demand of pregnancy revealed differences between treated and control offspring with respect to mean arterial pressure, CV function, cardiac strain, and left ventricular gene expression. In utero exposure to DMO also affected the subsequent generation. Gd18 fetal and placental weights were increased in treated F2 offspring. This study demonstrates that in utero chemical exposure may permanently alter the capacity of the postnatal heart to adapt to pregnancy and this may have transgenerational effects. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  3. Effects of water deficit and mycorrhizae on grain yield, reproductive and physiological traits of corn hybrids

    Directory of Open Access Journals (Sweden)

    Mikail Nordokht

    2018-06-01

    Full Text Available Increasing crop production to ensure future food security while reducing environmental pressure on agro-ecosystems requires improved water and nutrient use efficiency. the arid and semiarid regions of the world lack of sufficient water supply is the major problem for corn cultivation and is a restriction for its production, so studies on the growth limitation and germination of corn seeds under drought conditions seems very necessary. The effects of drought on plant growth depend on several factors such as plant genetic resistance, stage of growth and duration of plant expose to drought. The AMF are playing a vital role in sustainable agriculture because they enhance plant water relations, which improve the drought resistance of host plants. It is important to increase our understanding of AM fungal and maize genotype interactions and water condition on the symbiosis, and on the physiology and nutritional status of maize plants. Thus Mycorrhizae application and choosing suitable cultivar are of simple managements in decreasing drought effect. This investigation had done in order to investigate effect of irrigation regimes (irrigation after 70, 110 and 150 mm evaporaation from evaporate basin, Mycorrhizae (non application and application of Mycorrhizae and cultivar (704 and 640 on growth and yield of maize. A split factorial experiment based on randomized complete block design with three replications was conducted during growing season of 2015 at Islamic Azad University, Malekan Branch, Plots were then furrow irrigated in the mornings every week. Each block was including 12 plots. The size of each plot was 3.5m×4m, and there was in each plot, 5 rows with a distance of 75 cm, and the length of 4 m. The distance between plots was selected 150 cm, and the distance between blocks was selected 3 m. By mid August an area of 2.5 m from 3 line of plot area was separately harvested and traits were evaluated. MSTAT-C and EXCEL were used to analyze data

  4. Water Use Efficiency and Water Deficit Tolerance Indices in Terminal Growth Stages in Promising Bread Wheat genotypes

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    M. Nazeri

    2016-02-01

    Full Text Available Introduction During growth stages of wheat, anthesis and grain filling periods are the most susceptible to drought. Wheat cultivars that are more tolerant to terminal drought are more suitable to Mediterranean conditions. To increase water use efficiency, the target environment should be taken into account, because one trait might be effective in an environment but ineffective in another environment. In general, some traits like early vigour and root absorbtion capacity are so important in water deficient conditions. In recent years, increasing grain yield was due to increasing grain numbers. Although both the source and sink is considered as the limitation factors in increasing grain yield in old cultivars, even in the new cultivars sink seems to be more important. In fact, phenological adjustment adapted with seasonal precipitation pattern can improve water use efficiency in drought conditions. Suitable flowering time is the most important trait that is correlated with increasing water use efficiency in drought conditions. Materials and Methods In order to evaluate the level of drought tolerance in promising bread wheat lines, a split plot arrangements using randomized complete block design with three replications was carried out in 2008-09 and 2009-10 growing seasons at Torogh Agricultural Research Field Station, Mashhad. in. water limited conditions at three levels Optimum moisture conditions (L1, removal irrigation and using rain shelter from milky grain stage to maturity (L2, removal irrigation and using rainshelter from anthesis to maturity (L3 were assigned to main plots. Ten bread wheat lines include suitable for cold and dry regions (V1: (Toos, V2: (C-81-10, V3: (pishgam, V4: (C-84-4, V5: (C-84-8, V6: (C-D-85-15, V7: (C-D-85-9, V8: (C-D-84-5502, V9: (C-D-85-5502 and V10: (C-85-6 were randomized in sub-plots. Stress susceptibility index (SSI, stress tolerance index (STI and tolerance (TOL were calculated using following equations: D = 1

  5. The Potential Importance of Conservation, Restoration, and Altered Management Practices for Water Quality in the Wabash River Watershed

    Science.gov (United States)

    Non-point source (NPS) pollution is one of the leading causes of water quality impairment within the United States. Conservation, restoration and altered management (CRAM) practices may effectively reduce NPS pollutants discharge into receiving water bodies and enhance local and ...

  6. A biophysical approach using water deficit factor for daily estimations of evapotranspiration and CO2 uptake in Mediterranean environments

    Science.gov (United States)

    Helman, David; Lensky, Itamar M.; Osem, Yagil; Rohatyn, Shani; Rotenberg, Eyal; Yakir, Dan

    2017-09-01

    Estimations of ecosystem-level evapotranspiration (ET) and CO2 uptake in water-limited environments are scarce and scaling up ground-level measurements is not straightforward. A biophysical approach using remote sensing (RS) and meteorological data (RS-Met) is adjusted to extreme high-energy water-limited Mediterranean ecosystems that suffer from continuous stress conditions to provide daily estimations of ET and CO2 uptake (measured as gross primary production, GPP) at a spatial resolution of 250 m. The RS-Met was adjusted using a seasonal water deficit factor (fWD) based on daily rainfall, temperature and radiation data. We validated our adjusted RS-Met with eddy covariance flux measurements using a newly developed mobile lab system and the single active FLUXNET station operating in this region (Yatir pine forest station) at a total of seven forest and non-forest sites across a climatic transect in Israel (280-770 mm yr-1). RS-Met was also compared to the satellite-borne MODIS-based ET and GPP products (MOD16 and MOD17, respectively) at these sites.Results show that the inclusion of the fWD significantly improved the model, with R = 0.64-0.91 for the ET-adjusted model (compared to 0.05-0.80 for the unadjusted model) and R = 0.72-0.92 for the adjusted GPP model (compared to R = 0.56-0.90 of the non-adjusted model). The RS-Met (with the fWD) successfully tracked observed changes in ET and GPP between dry and wet seasons across the sites. ET and GPP estimates from the adjusted RS-Met also agreed well with eddy covariance estimates on an annual timescale at the FLUXNET station of Yatir (266 ± 61 vs. 257 ± 58 mm yr-1 and 765 ± 112 vs. 748 ± 124 gC m-2 yr-1 for ET and GPP, respectively). Comparison with MODIS products showed consistently lower estimates from the MODIS-based models, particularly at the forest sites. Using the adjusted RS-Met, we show that afforestation significantly increased the water use efficiency (the ratio of carbon uptake to ET) in this region

  7. Toxicity of drinking water disinfection byproducts: cell cycle alterations induced by the monohaloacetonitriles.

    Science.gov (United States)

    Komaki, Yukako; Mariñas, Benito J; Plewa, Michael J

    2014-10-07

    Haloacetonitriles (HANs) are a chemical class of drinking water disinfection byproducts (DBPs) that form from reactions between disinfectants and nitrogen-containing precursors, the latter more prevalent in water sources impacted by algae bloom and municipal wastewater effluent discharge. HANs, previously demonstrated to be genotoxic, were investigated for their effects on the mammalian cell cycle. Treating Chinese hamster ovary (CHO) cells with monoHANs followed by the release from the chemical treatment resulted in the accumulation of abnormally high DNA content in cells over time (hyperploid). The potency for the cell cycle alteration followed the order: iodoacetonitrile (IAN) > bromoacetonitrile (BAN) ≫ chloroacetonitrile (CAN). Exposure to 6 μM IAN, 12 μM BAN and 900 μM CAN after 26 h post-treatment incubation resulted in DNA repair; however, subsequent cell cycle alteration effects were observed. Cell proliferation of HAN-treated cells was suppressed for as long as 43 to 52 h. Enlarged cell size was observed after 52 h post-treatment incubation without the induction of cytotoxicity. The HAN-mediated cell cycle alteration was mitosis- and proliferation-dependent, which suggests that HAN treatment induced mitosis override, and that HAN-treated cells proceeded into S phase and directly into the next cell cycle. Cells with multiples genomes would result in aneuploidy (state of abnormal chromosome number and DNA content) at the next mitosis since extra centrosomes could compromise the assembly of bipolar spindles. There is accumulating evidence of a transient tetraploid state proceeding to aneuploidy in cancer progression. Biological self-defense systems to ensure genomic stability and to eliminate tetraploid cells exist in eukaryotic cells. A key tumor suppressor gene, p53, is oftentimes mutated in various types of human cancer. It is possible that HAN disruption of the normal cell cycle and the generation of aberrant cells with an abnormal number of

  8. Effects of arbuscular mycorrhizae on tomato yield, nutrient uptake, water relations, and soil carbon dynamics under deficit irrigation in field conditions.

    Science.gov (United States)

    Bowles, Timothy M; Barrios-Masias, Felipe H; Carlisle, Eli A; Cavagnaro, Timothy R; Jackson, Louise E

    2016-10-01

    Plant strategies to cope with future droughts may be enhanced by associations between roots and soil microorganisms, including arbuscular mycorrhizal (AM) fungi. But how AM fungi affect crop growth and yield, together with plant physiology and soil carbon (C) dynamics, under water stress in actual field conditions is not well understood. The well-characterized mycorrhizal tomato (Solanum lycopersicum L.) genotype 76R (referred to as MYC+) and the mutant nonmycorrhizal tomato genotype rmc were grown in an organic farm with a deficit irrigation regime and control regime that replaced evapotranspiration. AM increased marketable tomato yields by ~25% in both irrigation regimes but did not affect shoot biomass. In both irrigation regimes, MYC+ plants had higher plant nitrogen (N) and phosphorus (P) concentrations (e.g. 5 and 24% higher N and P concentrations in leaves at fruit set, respectively), 8% higher stomatal conductance (gs), 7% higher photosynthetic rates (Pn), and greater fruit set. Stem water potential and leaf relative water content were similar in both genotypes within each irrigation regime. Three-fold higher rates of root sap exudation in detopped MYC+ plants suggest greater capacity for water uptake through osmotic driven flow, especially in the deficit irrigation regime in which root sap exudation in rmc was nearly absent. Soil with MYC+ plants also had slightly higher soil extractable organic C and microbial biomass C at anthesis but no changes in soil CO2 emissions, although the latter were 23% lower under deficit irrigation. This study provides novel, field-based evidence for how indigenous AM fungi increase crop yield and crop water use efficiency during a season-long deficit irrigation and thus play an important role in coping with increasingly limited water availability in the future. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Study of Yield and Effective Traits in Bread Wheat Recombinant Inbred Lines (Triticum aestivum L. under Water Deficit Condition

    Directory of Open Access Journals (Sweden)

    S. Mohammad zadeh

    2013-11-01

    Full Text Available The effects some traits on seed yield of recombinant inbred lines of wheat under water deficit stress was studied. This research was done at the Agricultural Research Stations, Islamic Azad University, Tabriz Branch in 2010- 2011. 28 recombinant inbred lines of wheat bread with two parents (Norstar and Zagros in split plot experiment based on a randomized complete block design with three replications at two irrigation levels (70 and 140 mm evaporation from pan class A were studied. Analysis of variance indicated a significant genetic differences in all traits under study among the lines. Lines No. 32, 163 and 182 produced highest yield under both irrigation levels. Number of spikes, grains per spike and harvest index had the highest positive correlation with grain yield. Path analysis based on stepwise regression showed that under the normal irrigation conditions, number spike (0.556, number of grains per spike (0.278, weight of 1000 grain (0.259 and the drought stress number spike (0.430, straw yield (0.276 and peduncle length (0.323 had the most direct and positive effect on yield respectively.

  10. Gas exchange and mass distribution of the cowpea (Vigna unguiculata [L.] Walp. under water deficit

    Directory of Open Access Journals (Sweden)

    Cardona-Ayala Carlos Enrique

    2013-12-01

    Full Text Available Drought tolerance is important for the survival and productivity of plants in environments where drought periods are increasing as a result of climate variability attributable to natural causes and climate change caused by human activities. The objective of this study was to evaluate the dynamics of photosynthesis (A, stomatal conductance (gs and intrinsic water-use efficiency (WUE=A/gs as a function of soil moisture content over a period of drought and the post-stress recovery of 14 cowpea genotypes. The studied genotypes tolerated soil moisture tensions close to -2 Mpa with no permanent wilting. Starting at a soil hydric potential of -0.7 MP a, decreases in photosynthesis (A, stomatal conductance (gs and transpiration (E were evident, as well as an increase in A/gs, which varied by genotype. Estimating with regression models allowed for the discrimination of the degrees of drought tolerance between the cultivars. At 4 days after resuming hydration, no significant differences were found between the means of A, gs, A/gs and E, suggesting drought tolerance in all genotypes. The genotypes: L-047 and L-034 conserved between 4 and 6 leaves, displaying the highest delayed leaf senescence during drought. Furthermore, they presented the highest biomass at 16 days post-stress recovery

  11. Shifting species interactions in terrestrial dryland ecosystems under altered water availability and climate change.

    Science.gov (United States)

    McCluney, Kevin E; Belnap, Jayne; Collins, Scott L; González, Angélica L; Hagen, Elizabeth M; Nathaniel Holland, J; Kotler, Burt P; Maestre, Fernando T; Smith, Stanley D; Wolf, Blair O

    2012-08-01

    Species interactions play key roles in linking the responses of populations, communities, and ecosystems to environmental change. For instance, species interactions are an important determinant of the complexity of changes in trophic biomass with variation in resources. Water resources are a major driver of terrestrial ecology and climate change is expected to greatly alter the distribution of this critical resource. While previous studies have documented strong effects of global environmental change on species interactions in general, responses can vary from region to region. Dryland ecosystems occupy more than one-third of the Earth's land mass, are greatly affected by changes in water availability, and are predicted to be hotspots of climate change. Thus, it is imperative to understand the effects of environmental change on these globally significant ecosystems. Here, we review studies of the responses of population-level plant-plant, plant-herbivore, and predator-prey interactions to changes in water availability in dryland environments in order to develop new hypotheses and predictions to guide future research. To help explain patterns of interaction outcomes, we developed a conceptual model that views interaction outcomes as shifting between (1) competition and facilitation (plant-plant), (2) herbivory, neutralism, or mutualism (plant-herbivore), or (3) neutralism and predation (predator-prey), as water availability crosses physiological, behavioural, or population-density thresholds. We link our conceptual model to hypothetical scenarios of current and future water availability to make testable predictions about the influence of changes in water availability on species interactions. We also examine potential implications of our conceptual model for the relative importance of top-down effects and the linearity of patterns of change in trophic biomass with changes in water availability. Finally, we highlight key research needs and some possible broader impacts

  12. Altered intrinsic organisation of brain networks implicated in attentional processes in adult attention-deficit/hyperactivity disorder: a resting-state study of attention, default mode and salience network connectivity.

    Science.gov (United States)

    Sidlauskaite, Justina; Sonuga-Barke, Edmund; Roeyers, Herbert; Wiersema, Jan R

    2016-06-01

    Deficits in task-related attentional engagement in attention-deficit/hyperactivity disorder (ADHD) have been hypothesised to be due to altered interrelationships between attention, default mode and salience networks. We examined the intrinsic connectivity during rest within and between these networks. Six-minute resting-state scans were obtained. Using a network-based approach, connectivity within and between the dorsal and ventral attention, the default mode and the salience networks was compared between the ADHD and control group. The ADHD group displayed hyperconnectivity between the two attention networks and within the default mode and ventral attention network. The salience network was hypoconnected to the dorsal attention network. There were trends towards hyperconnectivity within the dorsal attention network and between the salience and ventral attention network in ADHD. Connectivity within and between other networks was unrelated to ADHD. Our findings highlight the altered connectivity within and between attention networks, and between them and the salience network in ADHD. One hypothesis to be tested in future studies is that individuals with ADHD are affected by an imbalance between ventral and dorsal attention systems with the former playing a dominant role during task engagement, making individuals with ADHD highly susceptible to distraction by salient task-irrelevant stimuli.

  13. Meteoric water alteration of soil and landscapes at Meridiani Planum, Mars

    Science.gov (United States)

    Amundson, Ronald

    2018-04-01

    The geomorphology and geochemistry data gathered by the MER Opportunity at Meridiani Planum is a rich data set relevant to soil research on Mars. Many of the data, particularly with respect to outcrops at Victoria Crater, have been only partially analyzed. Here, the previously published geochemical profile of Endurance Crater is compared to that of Victoria Crater, to understand aspects of the post-depositional aqueous and chemical alteration of the Meridiani land surface. The landsurface bears cracking patterns similar to those produced by multiple episodes of wetting and drying in expansive materials on Earth. The geochemical profiles at both craters are nearly identical, suggesting (using mass balance methods) that a very chemically homogenous sedimentary deposit has been engulfed by the apparent surficial addition of S, Cl, and Br (and associated cations) since exposure to the atmosphere. The chemistry and mineralogy at both locations is one where the most insoluble of the added components resides near the land surface (Ca sulfates), and the more soluble components are concentrated at greater depths in a vertical pattern consistent with their solubility in water. The profiles, when compared to those on Earth (and to physical constraints), are most similar those generated by the downward movement of meteoric water. When this aqueous alteration and soil formation occurred is not well constrained, but the processes occurred between late Noachian (?) to late Amazonian times. The exposure of the Victoria crater walls, which occurred likely less than 107 y ago (late Amazonian), shows the accumulation of dust as well as evidence for aqueous concentration of NaBr and/or CaBr, possibly by deliquescence. By direct comparison to Earth, the regional soil at Meridiani Planum is a Typic Petrogypsid (a sulfate cemented arid soil), bearing similarities to very ancient soils formed in the Atacama Desert of Chile. The amount of water required to produce the soils ranges from a

  14. A Soil-Plate Based Pipeline for Assessing Cereal Root Growth in Response to Polyethylene Glycol (PEG)-Induced Water Deficit Stress.

    Science.gov (United States)

    Nelson, Sven K; Oliver, Melvin J

    2017-01-01

    Drought is a serious problem that causes losses in crop-yield every year, but the mechanisms underlying how roots respond to water deficit are difficult to study under controlled conditions. Methods for assaying root elongation and architecture, especially for seedlings, are commonly achieved on artificial media, such as agar, moistened filter paper, or in hydroponic systems. However, it has been demonstrated that measuring root characteristics under such conditions does not accurately mimic what is observed when plants are grown in soil. Morphological changes in root behavior occur because of differences in solute diffusion, mechanical impedance, exposure to light (in some designs), and gas exchange of roots grown under these conditions. To address such deficiencies, we developed a quantitative method for assaying seedling root lengths and germination in soil using a plate-based approach with wheat as a model crop. We also further developed the method to include defined water deficits stress levels using the osmotic properties of polyethylene glycol (PEG). Seeds were sown into soil-filled vertical plates and grown in the dark. Root length measurements were collected using digital photography through the transparent lid under green lighting to avoid effects of white light exposure on growth. Photographs were analyzed using the cross-platform ImageJ plugin, SmartRoot, which can detect root edges and partially automate root detection for extraction of lengths. This allowed for quick measurements and straightforward and accurate assessments of non-linear roots. Other measurements, such as root width or angle, can also be collected by this method. An R function was developed to collect exported root length data, process and reformat the data, and output plots depicting root/shoot growth dynamics. For water deficit experiments, seedlings were transplanted side-by-side into well-watered plates and plates containing PEG solutions to simulate precise water deficits.

  15. Effects of enhanced ultraviolet-B radiation, water deficit, and their combination on UV-absorbing compounds and osmotic adjustment substances in two different moss species.

    Science.gov (United States)

    Hui, Rong; Zhao, Ruiming; Song, Guang; Li, Yixuan; Zhao, Yang; Wang, Yanli

    2018-05-01

    A simulation experiment was conducted to explore the influence of enhanced ultraviolet-B (UV-B) radiation, water deficit, and their combination on UV-absorbing compounds and osmotic adjustment substances of mosses Bryum argenteum and Didymodon vinealis isolated from biological soil crusts (BSCs) growing in a revegetated area of the Tengger Desert, China. Four levels of UV-B radiation and two gradients of water regime were employed. Compared with their controls, amounts of total flavonoids, chlorophyll, carotenoids, soluble sugars, and soluble proteins significantly decreased (p argenteum, D. vinealis was more resistant to enhanced UV-B and water deficit singly and in combination. These results suggest that the damage of enhanced UV-B on both species might be alleviated by water deficit. This alleviation is important for understanding the response of BSCs to UV-B radiation in future global climate change. This also provides novel insights into assessment damages of UV-B to BSC stability in arid and semiarid regions.

  16. Water deficit at different growth stages for common bean (Phaseolus vulgaris L. cv. Imbabello) on yield and water and nitrogen use efficiency

    International Nuclear Information System (INIS)

    Calvache, Marcelo Angel

    1997-03-01

    To identify specific growth stages of the common bean crop at which the plant is less sensitive to water stress, in which irrigation could be omitted without significant decrease in biological nitrogen fixation and final yield, a field experiment was conducted at 'La Tola' University Experiment Station, Tumbaco, Pichincha, Ecuador, on a sandy loam soil (Typic Haplustoll). The climate is tempered and dry (mean air temperature 16 C and mean relative humidity 74%) during the cropping season, and 123 mm of rainfall were recorded during the cropping period. The treatments consisted of the combinations of 7 irrigation regimes (IR1=normal watering; IR2= full stress; IR3= traditional practice; IR4=single stress at vegetation; IR5= flowering; IR6=yield formation and IR7=ripening) and 2 levels of applied N (20 and 80 kg/ha). These 14 treatment combinations were arranged and analysed in a split-plot design with 4 replications. The plot size was 33.6 m sub 2 (8 rows, 7 m long) with a population of 120.000 plants/ha. Irrigation treatments were started after uniform germination and crop establishment. Soil moisture was monitored with neutron probe down to the 0.50 m depth, 24 hours before and after each irrigation. Yield data show that treatments which had irrigation deficit had lower yield than those with supplementary irrigation (1% prob). The yield formation stage was the most sensitive to moisture stress, in which crop water use efficiency (0.46 kg/m3) was the lowest and the yield response factor (Ky=2.2.) was higher. Nitrogen fixation was significantly affected by water stress at the flowering and yield formation stages. (author)

  17. Resposta das culturas do girassol e do milho a diferentes cenários de rega deficitária Deficit irrigation as a criterion for irrigation water management with sunflower and maize crops

    Directory of Open Access Journals (Sweden)

    C. M. Toureiro

    2007-01-01

    the water use optimisation from an environmental point of view. This means that the decision criterion in irrigation management is “deficit irrigation”, rather than maximum ETc as the irrigation water amount. Some experiments with “deficit irrigation” of a sunflower crop (in 2004 irrigation season and maize (in 2005 were carried out in the Irrigation District of Divor (Alentejo, South Portugal. Crop growth and production parameters were evaluated relative to three experimental irrigation regimes: 1 irrigation opportunity and amount with soil available water equalling “optimum yield level”, this corresponding to a non restrictive water use by the crop, according to current procedure, irrigation amount corresponding to maximum ETc; 2 and 3 levels 1 and 2 of deficit irrigation, considering irrigation opportunity with soil available water respectively 10% and 30% under the “optimum yield level” and irrigation amounts 10% and 30% less than ETc between irrigation events. During the flowering periods normal irrigation for full ETc was practiced in all experiment plots. Crop yield data and the economic analysis show that a remarkable potential exists for saving water with “deficit irrigation”.

  18. Assessing Receiving Water Quality Impacts due to Flow Path Alteration in Residential Catchments, using the Stormwater and Wastewater Management Model

    Science.gov (United States)

    Wolosoff, S. E.; Duncan, J.; Endreny, T.

    2001-05-01

    The Croton water supply system, responsible for supplying approximately 10% of New York City's water, provides an opportunity for exploration into the impacts of significant terrestrial flow path alteration upon receiving water quality. Natural flow paths are altered during residential development in order to allow for construction at a given location, reductions in water table elevation in low lying areas and to provide drainage of increased overland flow volumes. Runoff conducted through an artificial drainage system, is prevented from being attenuated by the natural environment, thus the pollutant removal capacity inherent in most natural catchments is often limited to areas where flow paths are not altered by development. By contrasting the impacts of flow path alterations in two small catchments in the Croton system, with different densities of residential development, we can begin to identify appropriate limits to the re-routing of runoff in catchments draining into surface water supplies. The Stormwater and Wastewater Management Model (SWMM) will be used as a tool to predict the runoff quantity and quality generated from two small residential catchments and to simulate the potential benefits of changes to the existing drainage system design, which may improve water quality due to longer residence times.

  19. Sediment delivery estimates in water quality models altered by resolution and source of topographic data.

    Science.gov (United States)

    Beeson, Peter C; Sadeghi, Ali M; Lang, Megan W; Tomer, Mark D; Daughtry, Craig S T

    2014-01-01

    Moderate-resolution (30-m) digital elevation models (DEMs) are normally used to estimate slope for the parameterization of non-point source, process-based water quality models. These models, such as the Soil and Water Assessment Tool (SWAT), use the Universal Soil Loss Equation (USLE) and Modified USLE to estimate sediment loss. The slope length and steepness factor, a critical parameter in USLE, significantly affects sediment loss estimates. Depending on slope range, a twofold difference in slope estimation potentially results in as little as 50% change or as much as 250% change in the LS factor and subsequent sediment estimation. Recently, the availability of much finer-resolution (∼3 m) DEMs derived from Light Detection and Ranging (LiDAR) data has increased. However, the use of these data may not always be appropriate because slope values derived from fine spatial resolution DEMs are usually significantly higher than slopes derived from coarser DEMs. This increased slope results in considerable variability in modeled sediment output. This paper addresses the implications of parameterizing models using slope values calculated from DEMs with different spatial resolutions (90, 30, 10, and 3 m) and sources. Overall, we observed over a 2.5-fold increase in slope when using a 3-m instead of a 90-m DEM, which increased modeled soil loss using the USLE calculation by 130%. Care should be taken when using LiDAR-derived DEMs to parameterize water quality models because doing so can result in significantly higher slopes, which considerably alter modeled sediment loss. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  20. Effect of Azofert®on the yield of common bean varieties (Phaseolus vulgaris L.under conditions of water deficit

    Directory of Open Access Journals (Sweden)

    Wilfredo Estrada Prado

    2017-10-01

    Full Text Available The effect of Azofert® on the induction of tolerance of bean varieties to water deficit was evaluated. The experiment was developed during the period 2013-2014 at the Cooperative for Credits and Services Strengthened "Roberto Aguilar", Bayamo municipality, Granma, Cuba. Varieties CC-25-9R and Tomeguín-93 were used, which were applied four treatments, consisting of normal irrigation conditions throughout the crop cycle and conditions of water deficit at the beginning of flowering, formation and filling of the pods. In each case Azofert® was applied, with a dose of 200 mL per 50 kg of seed at the time of planting and as controls treatments were used without the application of this product. A randomized block design was used according to divided plots and four replicates. Ten plants were selected at random for each treatment to evaluate pod length (cm, pod width (mm, pod diameter (cm, number of pods per plant, number of seeds per pods, number of seeds per plant, weight of seeds per plant (g, weight of 100 seeds (g, as well as yield (t ha-1. The results showed the significant effect of Azofert ® in increasing tolerance to the water deficit of the studied varieties.

  1. Acclimation of biochemical and diffusive components of photosynthesis in rice, wheat and maize to heat and water deficit: implications for modeling photosynthesis

    Directory of Open Access Journals (Sweden)

    Juan Alejandro Perdomo

    2016-11-01

    Full Text Available The impact of the combined effects of heat stress, increased vapor pressure deficit (VPD and water deficit on the physiology of major crops needs to be better understood to help identifying the expected negative consequences of climate change and heat waves on global agricultural productivity. To address this issue, rice, wheat and maize plants were grown under control temperature (CT, 25°C, VPD 1.8 kPa, and a high temperature (HT, 38°C, VPD 3.5 kPa, both under well-watered (WW and water deficit (WD conditions. Gas-exchange measurements showed that, in general, WD conditions affected the leaf conductance to CO2, while growth at HT had a more marked effect on the biochemistry of photosynthesis. When combined, HT and WD had an additive effect in limiting photosynthesis. The negative impacts of the imposed treatments on the processes governing leaf gas-exchange were species-dependent. Wheat presented a higher sensitivity while rice and maize showed a higher acclimation potential to increased temperature. Rubisco and PEPC kinetic constants determined in vitro at 25°C and 38°C were used to estimate Vcmax, Jmax and Vpmax in the modeling of C3 and C4 photosynthesis. The results here obtained reiterate the need to use species-specific and temperature-specific values for Rubisco and PEPC kinetic constants for a precise parameterization of the photosynthetic response to changing environmental conditions in different crop species.

  2. The comparative study of anatomical structure of stem and ovule development of four cultivars of Glycine max L. merr in water deficit stress

    Directory of Open Access Journals (Sweden)

    Parissa Jonoubi

    2014-08-01

    Full Text Available Drought stress is one of the most important limiting factors that affect different aspects of plants vegetative and reproductive growth. It is one of the most important limiting factors of crop productivity. Regarding to the importance of soybean as an oilseed plant, and in order to identify the drought tolerant cultivars as well as evaluating of the effects of drought stress on anatomical structureof four soybean cultivars (Clin, Clark, M9 and L17, two series of experiments were carried out as randomized complete design. In the first experiment, at optimum conditions, plants were irrigated after 50 mm evaporation from germination to the end of growing period, whereas the second experiment was irrigated after 150 mm (sever stress evaporation from evaporation pan. The results showed that the effect of water deficit stress on cortex thickness and number of layers, Phloem and xylem thickness, diameter of vessel elements, number of vessel element rows, number of vessel elements in stem, pith and stele thickness, stem diameter and number of trichomes were significant. Relative acceleration of embryo sac development was observed in all plants under water deficit stress except for Clark cultivar. Evaluation of anatomical factors on these cultivars showed that Clin cultivar was more tolerant to water deficit stress compared to other cultivars.

  3. A biophysical approach using water deficit factor for daily estimations of evapotranspiration and CO2 uptake in Mediterranean environments

    Directory of Open Access Journals (Sweden)

    D. Helman

    2017-09-01

    Full Text Available Estimations of ecosystem-level evapotranspiration (ET and CO2 uptake in water-limited environments are scarce and scaling up ground-level measurements is not straightforward. A biophysical approach using remote sensing (RS and meteorological data (RS–Met is adjusted to extreme high-energy water-limited Mediterranean ecosystems that suffer from continuous stress conditions to provide daily estimations of ET and CO2 uptake (measured as gross primary production, GPP at a spatial resolution of 250 m. The RS–Met was adjusted using a seasonal water deficit factor (fWD based on daily rainfall, temperature and radiation data. We validated our adjusted RS–Met with eddy covariance flux measurements using a newly developed mobile lab system and the single active FLUXNET station operating in this region (Yatir pine forest station at a total of seven forest and non-forest sites across a climatic transect in Israel (280–770 mm yr−1. RS–Met was also compared to the satellite-borne MODIS-based ET and GPP products (MOD16 and MOD17, respectively at these sites.Results show that the inclusion of the fWD significantly improved the model, with R =  0.64–0.91 for the ET-adjusted model (compared to 0.05–0.80 for the unadjusted model and R =  0.72–0.92 for the adjusted GPP model (compared to R =  0.56–0.90 of the non-adjusted model. The RS–Met (with the fWD successfully tracked observed changes in ET and GPP between dry and wet seasons across the sites. ET and GPP estimates from the adjusted RS–Met also agreed well with eddy covariance estimates on an annual timescale at the FLUXNET station of Yatir (266 ± 61 vs. 257 ± 58 mm yr−1 and 765 ± 112 vs. 748 ± 124 gC m−2 yr−1 for ET and GPP, respectively. Comparison with MODIS products showed consistently lower estimates from the MODIS-based models, particularly at the forest sites. Using the adjusted RS–Met, we show that afforestation

  4. Alterations in 'water yield' associated with land use changes under different precipitation regime

    Science.gov (United States)

    Rohatyn, Shani; Ramati, Efrat; Tatarinov, Fyodor; Rotenberg, Eyal; Tas, Eran; Yakir, Dan

    2016-04-01

    Changes in rainfall regimes and land cover results in complex alterations in plant water use and in ecosystem water balance, which are not well quantified. This results in poor estimates of the 'water yield' (WY; the difference between precipitation, P, input and evapotranspiration, ET, losses), which provides the water available for runoff and re-charge, and ultimately also for human consumption. The objective of this study was to examine the interactions between the effects of land use change (from sparse shrubland to pine forest) on ecosystem WY, and changes in the precipitation regime (from humid Mediterranean to semi-arid conditions). We hypothesized that the forestation increased ET and reduced WY, but this impact diminishes with decreasing precipitation. We used a new approach centered on a custom-built mobile laboratory of eddy co-variance measurements deployed on a campaign basis (about two weeks per site repeated along the seasonal cycle), that allowed us to measure ecosystem-scale ET together with carbon and energy fluxes and meteorological parameters. Measurements were carried out between the years of 2012-2015 in three paired sites of Pinus halepensis forests and adjacent non-forest ecosystems along the rainfall gradient in Israel, from 755 to 290 mm in annual precipitation. Annual ET was estimated from the campaigns results based on multiple regression analyses with meteorological parameters (relative humidity, RH, temperature, T, and global radiation, Rg) from local meteorological stations that provided continuous data records. The results indicated that decrease in annual precipitation by a factor of ~2.5, resulted in decrease in ET by a factor of 2.4 from 685 mm, with WY=210 mm, in the humid forest, to 290 mm, with WY= 0 mm, in the dry forest. In the non-forest ecosystems ET showed relatively small decrease (by a factor of 1.3) from 285 mm, with WY=460 mm, to 220 mm, with WY=95 mm. The differences 'Forest-shrubland' in ET decreased from 400 mm to

  5. N. plumbaginifolia zeaxanthin epoxidase transgenic lines have unaltered baseline ABA accumulations in roots and xylem sap, but contrasting sensitivities of ABA accumulation to water deficit.

    Science.gov (United States)

    Borel, C; Audran, C; Frey, A; Marion-Poll, A; Tardieu, F; Simonneau, T

    2001-03-01

    A series of transgenic lines of Nicotiana plumbaginifolia with modified expression of zeaxanthin epoxidase gene (ZEP) provided contrasting ABA accumulation in roots and xylem sap. For mild water stress, concentration of ABA in the xylem sap ([ABA](xylem)) was clearly lower in plants underexpressing ZEP mRNA (complemented mutants and antisense transgenic lines) than in wild-type. In well-watered conditions, all lines presented similar [ABA](xylem) and similar ABA accumulation rates in detached roots. Plants could, therefore, be grown under normal light intensities and evaporative demand. Both ZEP mRNA abundance and ABA accumulation rate in roots increased with water deficit in all transgenic lines, except in complemented aba2-s1 mutants in which the ZEP gene was controlled by a constitutive promoter which does not respond to water deficit. These lines presented no change in root ABA content either with time or dehydration. The increase in ZEP mRNA abundance in roots with decreasing RWC was more pronounced in detached roots than in whole plants, suggesting a difference in mechanism. In all transgenic lines, a linear relationship was observed between predawn leaf water potential and [ABA](xylem), which could be reproduced in several experiments in the greenhouse and in the growth chamber. It is therefore possible to represent the effect of the transformation by a single parameter, thereby allowing the use of a quantitative approach to assist understanding of the behaviour of transgenic lines.

  6. Microbial metabolism alters pore water chemistry and increases consolidation of oil sands tailings.

    Science.gov (United States)

    Arkell, Nicholas; Kuznetsov, Petr; Kuznetsova, Alsu; Foght, Julia M; Siddique, Tariq

    2015-01-01

    Tailings produced during bitumen extraction from surface-mined oil sands ores (tar sands) comprise an aqueous suspension of clay particles that remain dispersed for decades in tailings ponds. Slow consolidation of the clays hinders water recovery for reuse and retards volume reduction, thereby increasing the environmental footprint of tailings ponds. We investigated mechanisms of tailings consolidation and revealed that indigenous anaerobic microorganisms altered porewater chemistry by producing CO and CH during metabolism of acetate added as a labile carbon amendment. Entrapped biogenic CO decreased tailings pH, thereby increasing calcium (Ca) and magnesium (Mg) cations and bicarbonate (HCO) concentrations in the porewater through dissolution of carbonate minerals. Soluble ions increased the porewater ionic strength, which, with higher exchangeable Ca and Mg, decreased the diffuse double layer of clays and increased consolidation of tailings compared with unamended tailings in which little microbial activity was observed. These results are relevant to effective tailings pond management strategies. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  7. Auxin Does Not Alter the Permeability of Pea Segments to Tritium-labeled Water.

    Science.gov (United States)

    Dowler, M J; Rayle, D L

    1974-02-01

    The possibility of an auxin effect on the permeability of pea (Pisum sativum L. ev. Alaska) segments to tritium-labeled water has been investigated by three separate laboratories, and the combined results are presented. We were unable to obtain any indication of a rapid effect of indoleacetic acid on the efflux of (3)HHO when pea segments previously "loaded" for 90 minutes with (3)HHO were transferred to unlabeled aqueous medium with indoleacetic acid. We were able to confirm that segments pretreated with (3)HHO plus indoleacetic acid for 60 to 90 minutes can show an enhanced (3)HHO release as compared with minus indoleacetic acid controls. However, this phenomenon appears to be due to an increased uptake of (3)HHO during the prolonged indoleacetic acid pretreatment, and therefore we conclude that auxin does not alter the permeability of pea segments to (3)HHO in either short term or long term tests. We confirm previous reports that the uptake of (3)HHO in pea segments proceeds largely through the cut surfaces, and that the cuticle is a potent barrier to (3)HHO flux.

  8. A Framework for Assessing Soil Moisture Deficit and Crop Water Stress at Multiple Space and Time Scales Under Climate Change Scenarios Using Model Platform, Satellite Remote Sensing, and Decision Support System

    KAUST Repository

    Mohanty, Binayak P.; Ines, Amor V. M.; Shin, Yongchul; Gaur, Nandita; Das, Narendra; Jana, Raghavendra Belur

    2016-01-01

    for sustainability of the growing global population. This warrants better predictive tools for aridity (based on precipitation, temperature, land use, and land cover), root zone (~top 1 m) soil moisture deficit, and crop water stress at farm, county, state, region

  9. Alteration mechanisms of UOX spent fuel under water; Mecanismes d'alteration sous eau du combustible irradie de type UOX

    Energy Technology Data Exchange (ETDEWEB)

    Muzeau, B

    2008-06-15

    The mechanisms of spent fuel alteration in aqueous media need to be understood on the assumption of a direct disposal of the assemblies in a geological formation or for long duration storage in pool. This work is a contribution to the study of the effects of the alpha and/or beta/gamma radiolysis of water on the oxidation and the dissolution of the UO{sub 2} matrix of UOX spent fuel. The effects of the alpha radiolysis, predominant in geological disposal conditions, were quantified by using samples of UO{sub 2} doped with plutonium. The leaching experiments highlighted two types of control for the matrix alteration according to the alpha activity. The first is based on the radiolytic oxidation of the surface and leads to a continuous release of uranium in solution whereas the second is based on a control by the solubility of uranium. An activity threshold, between 18 MBq.g{sup -1} and 33 MBq.g{sup -1}, was defined in a carbonated water. The value of this threshold is dependent on the experimental conditions and the presence or not of electro-active species such as hydrogen in the system. The effects of the alpha/beta/gamma radiolysis in relation with the storage conditions were also quantified. The experimental data obtained on spent fuel indicate that the alteration rate of the matrix based on the behaviour of tracer elements (caesium and strontium) reached a maximum value of some mg.m{sup -2}.d{sup -1}, even under very oxidizing conditions. The solubility of uranium and the nature of the secondary phases depend however on the extent of the oxidizing conditions. (author)

  10. Caffeine improves spatial learning deficits in an animal model of attention deficit hyperactivity disorder (ADHD) -- the spontaneously hypertensive rat (SHR).

    Science.gov (United States)

    Prediger, Rui D S; Pamplona, Fabrício A; Fernandes, Daniel; Takahashi, Reinaldo N

    2005-12-01

    The spontaneously hypertensive rat (SHR) is generally considered to be a suitable genetic model for the study of attention deficit hyperactivity disorder (ADHD), since it displays hyperactivity, impulsivity, poorly sustained attention, and deficits in learning and memory processes. Converging evidence suggests a primary role of disturbance in the dopaminergic neurotransmission in ADHD patients and in SHR, and in addition, some studies have also demonstrated alterations in adenosinergic neurotransmission in SHR. In the present study, adult female Wistar (WIS) and SHR rats received caffeine (1-10 mg/kg i.p.) 30 min before training, immediately after training, or 30 min before a test session in the spatial version of the Morris water maze. The effect of caffeine administration on WIS and SHR blood pressure was also measured. SHR needed significantly more trials in the training session to acquire the spatial information, but they displayed a similar profile to that of WIS rats in the test session (48 h later), demonstrating a selective deficit in spatial learning. Pre-training administration of caffeine (1-10 mg/kg i.p.) improved this spatial learning deficit in SHR, but did not alter the WIS performance. In contrast, post-training administration of caffeine (3 mg/kg i.p.) did not alter the SHR test performance, but increased memory retention in WIS rats. No dose of caffeine tested altered the mean blood pressure of WIS or SHR. These results demonstrate a selective spatial learning deficit in SHR which can be attenuated by pre-training administration of caffeine. In addition, the present findings indicate that the spatial learning deficit in SHR is not directly related to hypertension.

  11. Multi-Omics and Integrated Network Analyses Reveal New Insights into the Systems Relationships between Metabolites, Structural Genes, and Transcriptional Regulators in Developing Grape Berries (Vitis vinifera L. Exposed to Water Deficit

    Directory of Open Access Journals (Sweden)

    Stefania Savoi

    2017-07-01

    Full Text Available Grapes are one of the major fruit crops and they are cultivated in many dry environments. This study comprehensively characterizes the metabolic response of grape berries exposed to water deficit at different developmental stages. Increases of proline, branched-chain amino acids, phenylpropanoids, anthocyanins, and free volatile organic compounds have been previously observed in grape berries exposed to water deficit. Integrating RNA-sequencing analysis of the transcriptome with large-scale analysis of central and specialized metabolites, we reveal that these increases occur via a coordinated regulation of key structural pathway genes. Water deficit-induced up-regulation of flavonoid genes is also coordinated with the down-regulation of many stilbene synthases and a consistent decrease in stilbenoid concentration. Water deficit activated both ABA-dependent and ABA-independent signal transduction pathways by modulating the expression of several transcription factors. Gene-gene and gene-metabolite network analyses showed that water deficit-responsive transcription factors such as bZIPs, AP2/ERFs, MYBs, and NACs are implicated in the regulation of stress-responsive metabolites. Enrichment of known and novel cis-regulatory elements in the promoters of several ripening-specific/water deficit-induced modules further affirms the involvement of a transcription factor cross-talk in the berry response to water deficit. Together, our integrated approaches show that water deficit-regulated gene modules are strongly linked to key fruit-quality metabolites and multiple signal transduction pathways may be critical to achieve a balance between the regulation of the stress-response and the berry ripening program. This study constitutes an invaluable resource for future discoveries and comparative studies, in grapes and other fruits, centered on reproductive tissue metabolism under abiotic stress.

  12. Multi-Omics and Integrated Network Analyses Reveal New Insights into the Systems Relationships between Metabolites, Structural Genes, and Transcriptional Regulators in Developing Grape Berries (Vitis vinifera L.) Exposed to Water Deficit.

    Science.gov (United States)

    Savoi, Stefania; Wong, Darren C J; Degu, Asfaw; Herrera, Jose C; Bucchetti, Barbara; Peterlunger, Enrico; Fait, Aaron; Mattivi, Fulvio; Castellarin, Simone D

    2017-01-01

    Grapes are one of the major fruit crops and they are cultivated in many dry environments. This study comprehensively characterizes the metabolic response of grape berries exposed to water deficit at different developmental stages. Increases of proline, branched-chain amino acids, phenylpropanoids, anthocyanins, and free volatile organic compounds have been previously observed in grape berries exposed to water deficit. Integrating RNA-sequencing analysis of the transcriptome with large-scale analysis of central and specialized metabolites, we reveal that these increases occur via a coordinated regulation of key structural pathway genes. Water deficit-induced up-regulation of flavonoid genes is also coordinated with the down-regulation of many stilbene synthases and a consistent decrease in stilbenoid concentration. Water deficit activated both ABA-dependent and ABA-independent signal transduction pathways by modulating the expression of several transcription factors. Gene-gene and gene-metabolite network analyses showed that water deficit-responsive transcription factors such as bZIPs, AP2/ERFs, MYBs, and NACs are implicated in the regulation of stress-responsive metabolites. Enrichment of known and novel cis -regulatory elements in the promoters of several ripening-specific/water deficit-induced modules further affirms the involvement of a transcription factor cross-talk in the berry response to water deficit. Together, our integrated approaches show that water deficit-regulated gene modules are strongly linked to key fruit-quality metabolites and multiple signal transduction pathways may be critical to achieve a balance between the regulation of the stress-response and the berry ripening program. This study constitutes an invaluable resource for future discoveries and comparative studies, in grapes and other fruits, centered on reproductive tissue metabolism under abiotic stress.

  13. Regulation of glutamine synthetase isoforms in two differentially drought-tolerant rice (Oryza sativa L.) cultivars under water deficit conditions.

    Science.gov (United States)

    Singh, Kamal Krishna; Ghosh, Shilpi

    2013-02-01

    KEY MESSAGE : The regulation of GS isoforms by WD was organ specific. Two GS isoforms i.e. OsGS1;1 and OsGS2 were differentially regulated in IR-64 (drought-sensitive) and Khitish (drought-tolerant) cultivars of rice. Water deficit (WD) has adverse effect on rice (Oryza sativa L.) and acclimation requires essential reactions of primary metabolism to continue. Rice plants utilize ammonium as major nitrogen source, which is assimilated into glutamine by the reaction of Glutamine synthetase (GS, EC 6.3.1.2). Rice plants possess one gene (OsGS2) for chloroplastic GS2 and three genes (OsGS1;1, OsGS1;2 and OsGS1;3) for cytosolic GS1. Here, we report the effect of WD on regulation of GS isoforms in drought-sensitive (cv. IR-64) and drought-tolerant (cv. Khitish) rice cultivars. Under WD, total GS activity in root and leaf decreased significantly in IR-64 seedlings in comparison to Khitish seedlings. The reduced GS activity in IR-64 leaf was mainly due to decrease in GS2 activity, which correlated with decrease in corresponding transcript and polypeptide contents. GS1 transcript and polypeptide accumulated in leaf during WD, however, GS1 activity was maintained at a constant level. Total GS activity in stem of both the varieties was insensitive to WD. Among GS1 genes, OsGS1;1 expression was differently regulated by WD in the two rice varieties. Its transcript accumulated more abundantly in IR-64 leaf than in Khitish leaf. Following WD, OsGS1;1 mRNA level in stem and root tissues declined in IR-64 and enhanced in Khitish. A steady OsGS1;2 expression patterns were noted in leaf, stem and root of both the cultivars. Results suggest that OsGS2 and OsGS1;1 expression may contribute to drought tolerance of Khitish cultivar under WD conditions.

  14. The effect of vapour pressure deficit on stomatal conductance, sap pH and leaf-specific hydraulic conductance in Eucalyptus globulus clones grown under two watering regimes.

    Science.gov (United States)

    Hernandez, Maria Jose; Montes, Fernando; Ruiz, Federico; Lopez, Gustavo; Pita, Pilar

    2016-05-01

    Stomatal conductance has long been considered of key interest in the study of plant adaptation to water stress. The expected increase in extreme meteorological events under a climate change scenario may compromise survival in Eucalyptus globulus plantations established in south-western Spain. We investigated to what extent changes in stomatal conductance in response to high vapour pressure deficits and water shortage are mediated by hydraulic and chemical signals in greenhouse-grown E. globulus clones. Rooted cuttings were grown in pots and submitted to two watering regimes. Stomatal conductance, shoot water potential, sap pH and hydraulic conductance were measured consecutively in each plant over 4 weeks under vapour pressure deficits ranging 0·42 to 2·25 kPa. Evapotranspiration, growth in leaf area and shoot biomass were also determined. There was a significant effect of both clone and watering regime in stomatal conductance and leaf-specific hydraulic conductance, but not in sap pH. Sap pH decreased as water potential and stomatal conductance decreased under increasing vapour pressure deficit. There was no significant relationship between stomatal conductance and leaf-specific hydraulic conductance. Stomata closure precluded shoot water potential from falling below -1·8 MPa. The percentage loss of hydraulic conductance ranged from 40 to 85 %. The highest and lowest leaf-specific hydraulic conductances were measured in clones from the same half-sib families. Water shortage reduced growth and evapotranspiration, decreases in evapotranspiration ranging from 14 to 32 % in the five clones tested. Changes in sap pH seemed to be a response to changes in atmospheric conditions rather than soil water in the species. Stomata closed after a considerable amount of hydraulic conductance was lost, although intraspecific differences in leaf-specific hydraulic conductance suggest the possibility of selection for improved productivity under water-limiting conditions

  15. NMR studies of human blood cells in health and disease. I. Alterations of the plasma membrane water permeability of erythrocytes

    International Nuclear Information System (INIS)

    Katona, Eva; Doaga, I. O.; Radulet, Diana; Caplanusi, A.; Negreanu, Cezarina; Mihele, Denisa

    1999-01-01

    Alterations in pathological cases of the human erythrocyte membrane water permeability were investigated by using a Mn 2+ -doping 1 H nuclear magnetic resonance (NMR) technique. The temperature dependence of the apparent water diffusional exchange through erythrocyte membranes in chronic hepatitis, diabetes, dyslipidemia and essential hypertension was measured and compared to healthy controls. Using moderate manganese concentrations (9-18 mM) and Carr-Purcell-Meiboom-Gill pulse sequences with a large number of refocusing π pulses and short interpulse delay (100 μs) our values of the water exchange times (τ e ) across erythrocyte membranes, obtained within a 10 min time period following the moment of doping, were independent of the actual manganese concentration and the Arrhenius plot for water exchange was linear over the range of 22-42 deg C. A marked increase of the water exchange times values was observed in all studied disease states. In case of chronic hepatitis, diabetes and dyslipidemia the changes observed in transmembrane water exchange time were associated with significant increase in the apparent activation energy of the diffusional water permeability thus, pointing out alterations in the function of the erythrocyte water channel. (author)

  16. NMR studies of human blood cells in health and disease. I. Alterations of the plasma membrane water permeability of erythrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Katona, Eva; Doaga, I O; Radulet, Diana [Department of Biophysics, Carol Davila University of Medicine and Pharmaceutics, 8 Blvd. Eroilor Sanitari, POB 15-205, RO-76241 Bucharest (Romania); Caplanusi, A [Medical Biochemistry Department, Carol Davila University of Medicine and Pharmaceutics, 8 Blvd. Eroilor Sanitari, POB 15-205, RO-76241 Bucharest (Romania); Negreanu, Cezarina [Division of New Energy Conversion Methods, Institute of Research and Design for Thermoenergetic Equipment, ICPET-CERCETARE, Bucharest (Romania); Mihele, Denisa [Clinical Laboratory Department, Carol Davila University of Medicine and Pharmaceutics, 8 Blvd. Eroilor Sanitari, POB 15-205, RO-76241 Bucharest (Romania)

    1999-07-01

    Alterations in pathological cases of the human erythrocyte membrane water permeability were investigated by using a Mn{sup 2+}-doping {sup 1}H nuclear magnetic resonance (NMR) technique. The temperature dependence of the apparent water diffusional exchange through erythrocyte membranes in chronic hepatitis, diabetes, dyslipidemia and essential hypertension was measured and compared to healthy controls. Using moderate manganese concentrations (9-18 mM) and Carr-Purcell-Meiboom-Gill pulse sequences with a large number of refocusing {pi} pulses and short interpulse delay (100 {mu}s) our values of the water exchange times ({tau}{sub e}) across erythrocyte membranes, obtained within a 10 min time period following the moment of doping, were independent of the actual manganese concentration and the Arrhenius plot for water exchange was linear over the range of 22-42 deg C. A marked increase of the water exchange times values was observed in all studied disease states. In case of chronic hepatitis, diabetes and dyslipidemia the changes observed in transmembrane water exchange time were associated with significant increase in the apparent activation energy of the diffusional water permeability thus, pointing out alterations in the function of the erythrocyte water channel. (author)

  17. REM-sleep alterations in children with co-existence of tic disorders and attention-deficit/hyperactivity disorder: impact of hypermotor symptoms.

    Science.gov (United States)

    Kirov, Roumen; Banaschewski, Tobias; Uebel, Henrik; Kinkelbur, Jörg; Rothenberger, Aribert

    2007-06-01

    To characterize precisely the sleep pattern in children with co-existence of TD + ADHD. By means of polysomnography, sleep pattern was investigated in 19 children with TD + ADHD unmedicated before and during study and 19 healthy controls, matched for age, gender, and intelligence. Compared with healthy controls, children with TD + ADHD displayed shorter REM sleep latency and increased REM sleep duration. There was a negative correlational relationship between these REM-sleep alterations and they were determined by hyperactivity symptoms. Sleep in children with coexistence of TD + ADHD may be characterized by an elevated REM sleep drive. Common mechanisms are suggested to underpin hypermotor symptoms and REM sleep regulation.

  18. Converting Paddy Rice Field to Urban Use Dramatically Altered the Water and Energy Balances in Southern China

    Science.gov (United States)

    Hao, L.; Sun, G.; Liu, Y.; Qin, M.; Huang, X.; Fang, D.

    2017-12-01

    Paddy rice wetlands are the main land use type across southern China, which impact the regional environments by affecting evapotranspiration (ET) and other water and energy related processes. Our study focuses on the effects of land-cover change on water and energy processes in the Qinhuai River Basin, a typical subtropical humid region that is under rapid ecological and economical transformations. This study integrates multiple methods and techniques including remote sensing, water and energy balance model (i.e., Surface Energy Balance Algorithm for Land, SEBAL), ecohydrological model (i.e., Soil and Water Assessment Tool, SWAT), and ground observation (Eddy Covariance measurement, etc.). We found that conversion of paddy rice field to urban use led to rise in vapor pressure deficit (VPD) and reduction in ET, and thus resulted in changes in local and regional water and heat balance. The effects of the land-use change on ET and VPD overwhelmed the effects of regional climate warming and climate variability. We conclude that the ongoing large-scale urbanization of the rice paddy-dominated regions in humid southern China and East Asia will likely exacerbate environmental consequences (e.g., elevated storm-flow volume, aggravated flood risks, and intensified urban heat island and urban dry island effects). The potential role of vegetated land cover in moderating water and energy balances and maintaining a stable climate should be considered in massive urban planning and global change impact assessment in southern China.

  19. Iron oxides alter methanogenic pathways of acetate in production water of high-temperature petroleum reservoir.

    Science.gov (United States)

    Pan, Pan; Hong, Bo; Mbadinga, Serge Maurice; Wang, Li-Ying; Liu, Jin-Feng; Yang, Shi-Zhong; Gu, Ji-Dong; Mu, Bo-Zhong

    2017-09-01

    Acetate is a key intermediate in anaerobic crude oil biodegradation and also a precursor for methanogenesis in petroleum reservoirs. The impact of iron oxides, viz. β-FeOOH (akaganéite) and magnetite (Fe 3 O 4 ), on the methanogenic acetate metabolism in production water of a high-temperature petroleum reservoir was investigated. Methane production was observed in all the treatments amended with acetate. In the microcosms amended with acetate solely about 30% of the acetate utilized was converted to methane, whereas methane production was stimulated in the presence of magnetite (Fe 3 O 4 ) resulting in a 48.34% conversion to methane. Methane production in acetate-amended, β-FeOOH (akaganéite)-supplemented microcosms was much faster and acetate consumption was greatly improved compared to the other conditions in which the stoichiometric expected amounts of methane were not produced. Microbial community analysis showed that Thermacetogenium spp. (known syntrophic acetate oxidizers) and hydrogenotrophic methanogens closely related to Methanothermobacter spp. were enriched in acetate and acetate/magnetite (Fe 3 O 4 ) microcosms suggesting that methanogenic acetate metabolism was through hydrogenotrophic methanogenesis fueled by syntrophic acetate oxidizers. The acetate/β-FeOOH (akaganéite) microcosms, however, differed by the dominance of archaea closely related to the acetoclastic Methanosaeta thermophila. These observations suggest that supplementation of β-FeOOH (akaganéite) accelerated the production of methane further, driven the alteration of the methanogenic community, and changed the pathway of acetate methanogenesis from hydrogenotrophic methanogenesis fueled by syntrophic acetate oxidizers to acetoclastic.

  20. Combined Treatment With Environmental Enrichment and (-)-Epigallocatechin-3-Gallate Ameliorates Learning Deficits and Hippocampal Alterations in a Mouse Model of Down Syndrome.

    Science.gov (United States)

    Catuara-Solarz, Silvina; Espinosa-Carrasco, Jose; Erb, Ionas; Langohr, Klaus; Gonzalez, Juan Ramon; Notredame, Cedric; Dierssen, Mara

    2016-01-01

    Intellectual disability in Down syndrome (DS) is accompanied by altered neuro-architecture, deficient synaptic plasticity, and excitation-inhibition imbalance in critical brain regions for learning and memory. Recently, we have demonstrated beneficial effects of a combined treatment with green tea extract containing (-)-epigallocatechin-3-gallate (EGCG) and cognitive stimulation in young adult DS individuals. Although we could reproduce the cognitive-enhancing effects in mouse models, the underlying mechanisms of these beneficial effects are unknown. Here, we explored the effects of a combined therapy with environmental enrichment (EE) and EGCG in the Ts65Dn mouse model of DS at young age. Our results show that combined EE-EGCG treatment improved corticohippocampal-dependent learning and memory. Cognitive improvements were accompanied by a rescue of cornu ammonis 1 (CA1) dendritic spine density and a normalization of the proportion of excitatory and inhibitory synaptic markers in CA1 and dentate gyrus.

  1. Early phyllosilicates formed by alteration of R7T7 glass in water at 250 deg C

    International Nuclear Information System (INIS)

    Vernaz, E.; Dussossoy, J.L.; Caurel, J.; Crovisier, J.L.

    1991-01-01

    T7T7 glass samples have been altered during periods of one and seven days at 250 deg C in distilled water. Ultramicrotomic thin sections were performed in the outermost part of the glass for a study under analytical transmission electron microscope. After one day the alteration layer is about 5 μm thick. It is made up of sheeted silicated particles, tentatively identified as septechlorite (7 A intervals) mixed with an intercrystalline amorphous matrix of different composition. After seven days the alteration layer is about 11 μm thick. It is made up of sheeted silicated particles of smectite type (10 A intervals). No 7 A particles were found in the seven days sample. This study illustrates the capacity of poorly crystalline phyllosilicates to adapt to the chemical changes in solution. 15 refs., 4 tabs., 2 plates

  2. Effect of water deficit on leaf phenolic composition, gas exchange, oxidative damage and antioxidant activity of four Greek olive (Olea europaea L.) cultivars.

    Science.gov (United States)

    Petridis, Antonios; Therios, Ioannis; Samouris, Georgios; Koundouras, Stefanos; Giannakoula, Anastasia

    2012-11-01

    The olive tree (Olea europaea L.) is often exposed to severe water stress during the summer season. In this study, we determined the changes in total phenol content, oleuropein and hydroxytyrosol in the leaves of four olive cultivars ('Gaidourelia', 'Kalamon', 'Koroneiki' and 'Megaritiki') grown under water deficit conditions for two months. Furthermore, we investigated the photosynthetic performance in terms of gas exchange and chlorophyll a fluorescence, as well as malondialdehyde content and antioxidant activity. One-year-old self-rooted plants were subjected to three irrigation treatments that received a water amount equivalent to 100% (Control, C), 66% (Field Capacity 66%, FC(66)) and 33% (Field Capacity 33%, FC(33)) of field capacity. Measurements were conducted 30 and 60 days after the initiation of the experiment. Net CO(2) assimilation rate, stomatal conductance and F(v)/F(m) ratio decreased only in FC(33) plants. Photosynthetic rate was reduced mainly due to stomatal closure, but damage to PSII also contributed to this decrease. Water stress induced the accumulation of phenolic compounds, especially oleuropein, suggesting their role as antioxidants. Total phenol content increased in FC(33) treatment and oleuropein presented a slight increase in FC(66) and a sharper one in FC(33) treatment. Hydroxytyrosol showed a gradual decrease as water stress progressed. Malondialdehyde (MDA) content increased due to water stress, mostly after 60 days, while antioxidant activity increased for all cultivars in the FC(33) treatment. 'Gaidourelia' could be considered as the most tolerant among the tested cultivars, showing higher phenolic concentration and antioxidant activity and lower lipid peroxidation and photochemical damage after two months of water stress. The results indicated that water stress affected olive tree physiological and biochemical parameters and magnitude of this effect depended on genotype, the degree of water limitation and duration of treatment

  3. The Effect of Water Deficit stress on Osmotic Metabolites and Anti Oxidant System and Grain and Oil Yield of Amaranth CV. Koniz

    Directory of Open Access Journals (Sweden)

    Mehrdad Yarnia

    2015-01-01

    Full Text Available Drought is one of the most important environmental stresses that highly affect crop growth and yield. But the response of crops to stress depending on the timing of crop growth stages is different. The purpose of this study was to investigate effect of different levels of water stress (irrigation after 50, 80, 110, 140 and 170 mm evaporation from pan on different stages of Amaranth growth (establishment, branching, flowering and grain filling. To find the effects of water deficit stress on this plant it was decided to determine its protein percentage, oil and grain yields under drought stress. Evaluation of physiological characteristics as to the extent of osmotic adjustment and antioxidant activity was also carried out. Results showed that water deficit stress,depending on the severity and duration of stress, caused a reduction between between a minimum of 10 to a maximum of 89 percent in yield, 28 to 70 percent in harvest index, 12 to 32 percent in grain protein and 29 to 97 percent in oil yield. This indicates the high sensitivity of grain and oil yields to severe and prolonged drought stresses. Changes in osmotic substances (proline and soluble carbohydrates showed that this crop under water stress conditions increased proline and soluble carbohydrates by 31 and 50 percents, respectively. Thus, if could be said that under severe droughts the ability of crops to cops with drought will be reduced. Similarly, amaranth, to cope with water stress, increases the amount of antioxidant enzymes like catalase, peroxidase and super oxid dismutase up to 53, 23 and 79%, respectively. Higher amount of super oxid dismutase enzyme produce as the result of drought stress may play an important role to cope with reactive oxygen species and oxidative stresses.

  4. Gastrodia elata Bl. Attenuated learning deficits induced by forced-swimming stress in the inhibitory avoidance task and Morris water maze.

    Science.gov (United States)

    Chen, Pei-Ju; Liang, Keng-Chen; Lin, Hui-Chen; Hsieh, Ching-Liang; Su, Kuan-Pin; Hung, Mei-Chu; Sheen, Lee-Yan

    2011-06-01

    This study adopted the forced-swimming paradigm to induce depressive symptoms in rats and evaluated the effects on learning and memory processing. Furthermore, the effects of the water extract of Gastrodia elata Bl., a well-known Chinese traditional medicine, on amnesia in rats subjected to the forced-swimming procedure were studied. Rats were subjected to the forced-swimming procedure, and the inhibitory avoidance task and Morris water maze were used to assess learning and memory performance. The acquisition of the two tasks was mostly impaired after the 15-minute forced-swimming procedure. Administration of the water extract of G. elata Bl. for 21 consecutive days at a dosage of 0.5 or 1.0 g/kg of body weight significantly improved retention in the inhibitory avoidance test, and the lower dose showed a better effect than the higher one and the antidepressant fluoxetine (18 mg/kg of body weight). In the Morris water maze, the lower dose of the water extract of G. elata Bl. significantly improved retention by shortening escape latency in the first test session and increasing the time in searching the target zone during the probe test. These findings suggest that water extracts of G. elata Bl. ameliorate the learning and memory deficits induced by forced swimming.

  5. Effect of Zinc Sulfate and Ascorbic Acid on some Morpho-Physiological Traits of Echinacea purpurea (Purple coneflower under Water Deficit Conditions

    Directory of Open Access Journals (Sweden)

    F Farahvash

    2015-05-01

    Full Text Available To quantify the response of some morpho-physiological traits of Echinacea purpurea to thr application of zinc sulfate and ascorbic acid under water deficit, an experiment was carried out in split plot factorial based on RCBD with three replications at the Agricultural Research Station of Islamic Azad University, Tabriz Branch in 2011-12. Experimental factors consisted of water stress as the main factor with three levels (irrigation after70mm evaporation, irrigation after120mm evaporation and irrigation after 170mm evaporation from class A pan, Secondary factor consisted of: application of microelement with two levels (control and application of zinc sulfate 0.005 concentration and ascorbic acid with four levels (not application, application of 50 mg/l of ascorbic acid, application of 100 mg/l of ascorbic acid and application of 150 mg/l of ascorbic acid. The results showed that the effect of water deficit on purple coneflower caused significant differences in diameter of stem, number of flowering branch, stomata density, zinc concentration of aerial parts plant, fresh weight, relative water content of leaf, LAI, proline concentration, crop growth rate, relative growth rate and net assimilation rate. Comparison of means for water deficits between the different levels of drought stress showed that the maximum LAI, with 2.85, belonged to control. Comparison of means for interaction effects between drought stress and application of zinc sulfate revealed that the maximum proline concentration belonged to spraying plants with zinc sulfate at irrigation after 170mm evaporation from class A pan with 10.16 mg/g.fw. Minimum proline concentration was due to without applying zinc sulfate in complete irrigation (control with 0.08 mg/g.fw. Maximum crop growth rate with 6.77 g/m2.day was was related to control and the minimum, with 4.16 g/m2.day, to irrigation after 170mm. Maximum relative crop growth rate, with 0.19 g/m2.day, belonged to control and the

  6. Effect of soil structures and nitrogen nutrition on yield and yield components of Barley: utilization of δC13 as an indicator of water deficit

    International Nuclear Information System (INIS)

    Wibawa, Gede; Menard, J.M.

    1995-01-01

    The objective of this study was to analyze the effect of combination between soil structures and nitrogen doses on the yield and its components. The treatments consisted of three soil structures: loose(O), block(B) and alternate between loose and compact(G) and five doses of nitrogen ranging from 0 to 200 kg/ha which were tested at TASS2, TASS3 and TASS4. Results showed that soil structures influenced nitrogen absorption and yield mainly through grain number/m2. The soil structure effect depends greatly on the climate. This study proved that carbon isotopic composition δC 1 3 related greatly to the carbon and water nutrition of the plant, therefore it can be used as an indicator of water deficit. (author), 17 refs, 2 tabs, 7 figs

  7. Understanding water deficit stress-induced changes in the basic metabolism of higher plants - biotechnologically and sustainably improving agriculture and the ecoenvironment in arid regions of the globe.

    Science.gov (United States)

    Shao, Hong-Bo; Chu, Li-Ye; Jaleel, C Abdul; Manivannan, P; Panneerselvam, R; Shao, Ming-An

    2009-01-01

    Water is vital for plant growth, development and productivity. Permanent or temporary water deficit stress limits the growth and distribution of natural and artificial vegetation and the performance of cultivated plants (crops) more than any other environmental factor. Productive and sustainable agriculture necessitates growing plants (crops) in arid and semiarid regions with less input of precious resources such as fresh water. For a better understanding and rapid improvement of soil-water stress tolerance in these regions, especially in the water-wind eroded crossing region, it is very important to link physiological and biochemical studies to molecular work in genetically tractable model plants and important native plants, and further extending them to practical ecological restoration and efficient crop production. Although basic studies and practices aimed at improving soil water stress resistance and plant water use efficiency have been carried out for many years, the mechanisms involved at different scales are still not clear. Further understanding and manipulating soil-plant water relationships and soil-water stress tolerance at the scales of ecology, physiology and molecular biology can significantly improve plant productivity and environmental quality. Currently, post-genomics and metabolomics are very important in exploring anti-drought gene resources in various life forms, but modern agriculturally sustainable development must be combined with plant physiological measures in the field, on the basis of which post-genomics and metabolomics have further practical prospects. In this review, we discuss physiological and molecular insights and effects in basic plant metabolism, drought tolerance strategies under drought conditions in higher plants for sustainable agriculture and ecoenvironments in arid and semiarid areas of the world. We conclude that biological measures are the bases for the solutions to the issues relating to the different types of

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

    Science.gov (United States)

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

    1990-01-01

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

  9. Rapid increases in permeability and porosity of bentonite-sand mixtures due to alteration by water vapor

    International Nuclear Information System (INIS)

    Couture, R.A.

    1984-01-01

    Packed columns of canister packing material containing 25% bentonite and 75% quartz or basalt sand, were exposed to water vapor at temperatures up t 260 0 C. The permeabilities of the columns were subsequently measured after complete saturation with liquid water in a pressurized system. Exposure to water vapor caused irreversible increases in permeability by factors of up to 10 5 . After saturation with liquid water, the permeability was nearly independent of temperature. The increases in permeability were due to a large decrease in the ability of the bentonite to swell in water. Calculations suggest that swelling of bentonite altered at 250 0 C was not sufficient to fill the pore spaces. If the pore spaces are filled, the mixture will form an effective barrier against flow, diffusion, and transport of colloids. The results suggest that if bentonite-based canister packing material is exposed even briefly to water vapor at high temperatures in a high-level nuclear waste repository, its performance will be seriously impaired. The problem is less severe if the proportion of bentonite is high and the material is highly compacted. Previous results show significant degradation of bentonite by water vapor at temperatures as low as 150 0 C. This suggests that in some repositories, backfill in tunnels and drifts may also be affected. 9 references, 5 figures, 1 table

  10. Overexpression of Laccaria bicolor aquaporin JQ585595 alters root water transport properties in ectomycorrhizal white spruce (Picea glauca) seedlings.

    Science.gov (United States)

    Xu, Hao; Kemppainen, Minna; El Kayal, Walid; Lee, Seong Hee; Pardo, Alejandro G; Cooke, Janice E K; Zwiazek, Janusz J

    2015-01-01

    The contribution of hyphae to water transport in ectomycorrhizal (ECM) white spruce (Picea glauca) seedlings was examined by altering expression of a major water-transporting aquaporin in Laccaria bicolor. Picea glauca was inoculated with wild-type (WT), mock transgenic or L. bicolor aquaporin JQ585595-overexpressing (OE) strains and exposed to root temperatures ranging from 5 to 20°C to examine the root water transport properties, physiological responses and plasma membrane intrinsic protein (PIP) expression in colonized plants. Mycorrhization increased shoot water potential, transpiration, net photosynthetic rates, root hydraulic conductivity and root cortical cell hydraulic conductivity in seedlings. At 20°C, OE plants had higher root hydraulic conductivity compared with WT plants and the increases were accompanied by higher expression of P. glauca PIP GQ03401_M18.1 in roots. In contrast to WT L. bicolor, the effects of OE fungi on root and root cortical cell hydraulic conductivities were abolished at 10 and 5°C in the absence of major changes in the examined transcript levels of P. glauca root PIPs. The results provide evidence for the importance of fungal aquaporins in root water transport of mycorrhizal plants. They also demonstrate links between hyphal water transport, root aquaporin expression and root water transport in ECM plants. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  11. Alteration of a borosilicate glass in cemented water: antagonist effects of calcium

    International Nuclear Information System (INIS)

    Frizon, F.; Depierre, S.; Angeli, F.; Gin, S.

    2013-01-01

    In the framework of the storage of radioactive wastes in deep geological layers, vitrified waste may be in contact with an environment saturated with solutions stemming from various stages of cement degradation. A series of experiments has been performed to assess how a basic aqueous calcium-rich solution can impact the mechanisms and kinetics of glass alteration. This study shows that 2 main parameters have an impact on the kinetics of the dissolution of glass: the S/V ratio (the glass surface divided by the volume of solution) and the calcium concentration. The calcium concentration is a key parameter whatever the kinetics of glass degradation. In a diluted medium with a pH over 11, the kinetics of glass alteration slows down along with an increase in calcium concentration. What happens is that the silicon flux being too weak to allow the nucleation of C-S-H phases, calcium can penetrate the alteration layer which leads to a better retention of glass components through specific silicon-calcium reactivity and a slowing down of the glass alteration kinetics. On the contrary in a confined environment, a high concentration in calcium leads to the precipitation of C-S-H and to less C-S-H available to cover glass grains diminishing its passivating effect and consequently the dissolving of glass can keep on at more or less the same pace. (A.C.)

  12. Three Gorges Dam alters the Changjiang (Yangtze) river water cycle in the dry seasons: Evidence from H-O isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Kai [School of Ocean and Earth Science, Tongji University, Shanghai, 200092 (China); State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092 (China); Yang, Shouye, E-mail: syyang@tongji.edu.cn [State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092 (China); Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266061 (China); Lian, Ergang [School of Ocean and Earth Science, Tongji University, Shanghai, 200092 (China); State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092 (China); Li, Chao [State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092 (China); Yang, Chengfan; Wei, Hailun [School of Ocean and Earth Science, Tongji University, Shanghai, 200092 (China); State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092 (China)

    2016-08-15

    As the largest hydropower project in the world, the Three Gorges Dam (TGD) has attracted great concerns in terms of its impact on the Changjiang (Yangtze) River and coastal marine environments. In this study, we measured or collected the H-O isotopic data of river water, groundwater and precipitation in the mid-lower Changjiang catchment during the dry seasons of recent years. The aim was to investigate the changes of river water cycle in response to the impoundment of the TGD. Isotopic evidences suggested that the mid-lower Changjiang river water was ultimately derived from precipitation, but dominated by the mixing of different water masses with variable sources and isotopic signals as well. The isotopic parameter “deuterium excess” (d-excess) yielded large fluctuations along the mid-lower mainstream during the initial stage of the TGD impoundment, which was inherited from the upstream water with inhomogeneous isotopic signals. However, as the reservoir water level rising to the present stage, small variability of d-excess was observed along the mid-lower mainstream. This discrepancy could be explained that the TGD impoundment had significantly altered the water cycle downstream the dam, with the rising water level increasing the residence time and enhancing the mixing of reservoir water derived from upstream. This eventually resulted in the homogenization of reservoir water, and thus small fluctuations of d-excess downstream the dam after the quasi-normal stage (2008 to present). We infer that the retention effect of large reservoirs has greatly buffered the d-excess natural variability of water cycle in large river systems. Nevertheless, more research attention has to be paid to the damming effect on the water cycle in the river, estuarine and coastal areas, especially during the dry seasons. - Highlights: • Stable H-O isotopes indicate the Changjiang river water cycle in dry seasons. • The isotopic parameter “d-excess” reveals the origins of

  13. Three Gorges Dam alters the Changjiang (Yangtze) river water cycle in the dry seasons: Evidence from H-O isotopes

    International Nuclear Information System (INIS)

    Deng, Kai; Yang, Shouye; Lian, Ergang; Li, Chao; Yang, Chengfan; Wei, Hailun

    2016-01-01

    As the largest hydropower project in the world, the Three Gorges Dam (TGD) has attracted great concerns in terms of its impact on the Changjiang (Yangtze) River and coastal marine environments. In this study, we measured or collected the H-O isotopic data of river water, groundwater and precipitation in the mid-lower Changjiang catchment during the dry seasons of recent years. The aim was to investigate the changes of river water cycle in response to the impoundment of the TGD. Isotopic evidences suggested that the mid-lower Changjiang river water was ultimately derived from precipitation, but dominated by the mixing of different water masses with variable sources and isotopic signals as well. The isotopic parameter “deuterium excess” (d-excess) yielded large fluctuations along the mid-lower mainstream during the initial stage of the TGD impoundment, which was inherited from the upstream water with inhomogeneous isotopic signals. However, as the reservoir water level rising to the present stage, small variability of d-excess was observed along the mid-lower mainstream. This discrepancy could be explained that the TGD impoundment had significantly altered the water cycle downstream the dam, with the rising water level increasing the residence time and enhancing the mixing of reservoir water derived from upstream. This eventually resulted in the homogenization of reservoir water, and thus small fluctuations of d-excess downstream the dam after the quasi-normal stage (2008 to present). We infer that the retention effect of large reservoirs has greatly buffered the d-excess natural variability of water cycle in large river systems. Nevertheless, more research attention has to be paid to the damming effect on the water cycle in the river, estuarine and coastal areas, especially during the dry seasons. - Highlights: • Stable H-O isotopes indicate the Changjiang river water cycle in dry seasons. • The isotopic parameter “d-excess” reveals the origins of

  14. Comparison of inhibition of N2 fixation and ureide accumulation under water deficit in four common bean genotypes of contrasting drought tolerance.

    Science.gov (United States)

    Coleto, I; Pineda, M; Rodiño, A P; De Ron, A M; Alamillo, J M

    2014-05-01

    Drought is the principal constraint on world production of legume crops. There is considerable variability among genotypes in sensitivity of nitrogen fixation to drought, which has been related to accumulation of ureides in soybean. The aim of this study was to search for genotypic differences in drought sensitivity and ureide accumulation in common bean (Phaseolus vulgaris) germplasm that may be useful in the improvement of tolerance to water deficit in common bean. Changes in response to water deficit of nitrogen fixation rates, ureide content and the expression and activity of key enzymes for ureide metabolism were measured in four P. vulgaris genotypes differing in drought tolerance. A variable degree of drought-induced nitrogen fixation inhibition was found among the bean genotypes. In addition to inhibition of nitrogen fixation, there was accumulation of ureides in stems and leaves of sensitive and tolerant genotypes, although this was higher in the leaves of the most sensitive ones. In contrast, there was no accumulation of ureides in the nodules or roots of stressed plants. In addition, the level of ureides in the most sensitive genotype increased after inhibition of nitrogen fixation, suggesting that ureides originate in vegetative tissues as a response to water stress, probably mediated by the induction of allantoinase. Variability of drought-induced inhibition of nitrogen fixation among the P. vulgaris genotypes was accompanied by subsequent accumulation of ureides in stems and leaves, but not in nodules. The results indicate that shoot ureide accumulation after prolonged exposure to drought could not be the cause of inhibition of nitrogen fixation, as has been suggested in soybean. Instead, ureides seem to be produced as part of a general response to stress, and therefore higher accumulation might correspond to higher sensitivity to the stressful conditions.

  15. The effects of the recent minimum temperature and water deficit increases on Pinus pinaster wood radial growth and density in southern Portugal.

    Directory of Open Access Journals (Sweden)

    Cathy Béatrice Kurz Besson

    2016-08-01

    Full Text Available Western Iberia has recently shown increasing frequency of drought conditions coupled with heatwave events, leading to exacerbated limiting climatic conditions for plant growth. It is not clear to what extent wood growth and density of agroforestry species have suffered from such changes or recent extreme climate events.To address this question, tree-ring width and density chronologies were built for a P. pinaster stand in southern Portugal and correlated with climate variables, including the minimum, mean and maximum temperatures and the number of cold days. Monthly and maximum daily precipitations were also analyzed as well as dry spells. The drought effect was assessed using the standardized precipitation-evapotranspiration (SPEI multi-scalar drought index, between 1 to 24-months. The climate-growth/density relationships were evaluated for the period 1958-2011.We show that both wood radial growth and density highly benefit from the strong decay of cold days and the increase of minimum temperature. Yet the benefits are hindered by long-term water deficit, which results in different levels of impact on wood radial growth and density. Despite of the intensification of long-term water deficit, tree-ring width appears to benefit from the minimum temperature increase, whereas the effects of long-term droughts significantly prevail on tree-ring density. Our results further highlight the dependency of the species on deep water sources after the juvenile stage. The impact of climate changes on long-term droughts and their repercussion on the shallow groundwater table and P. pinaster’s vulnerability are also discussed. This work provides relevant information for forest management in the semi-arid area of the Alentejo region of Portugal. It should ease the elaboration of mitigation strategies to assure P. pinaster’s production capacity and quality in response to more arid conditions in the near future in the region.

  16. Water deprivation induces appetite and alters metabolic strategy in Notomys alexis: unique mechanisms for water production in the desert.

    Science.gov (United States)

    Takei, Yoshio; Bartolo, Ray C; Fujihara, Hiroaki; Ueta, Yoichi; Donald, John A

    2012-07-07

    Like many desert animals, the spinifex hopping mouse, Notomys alexis, can maintain water balance without drinking water. The role of the kidney in producing a small volume of highly concentrated urine has been well-documented, but little is known about the physiological mechanisms underpinning the metabolic production of water to offset obligatory water loss. In Notomys, we found that water deprivation (WD) induced a sustained high food intake that exceeded the pre-deprivation level, which was driven by parallel changes in plasma leptin and ghrelin and the expression of orexigenic and anorectic neuropeptide genes in the hypothalamus; these changed in a direction that would stimulate appetite. As the period of WD was prolonged, body fat disappeared but body mass increased gradually, which was attributed to hepatic glycogen storage. Switching metabolic strategy from lipids to carbohydrates would enhance metabolic water production per oxygen molecule, thus providing a mechanism to minimize respiratory water loss. The changes observed in appetite control and metabolic strategy in Notomys were absent or less prominent in laboratory mice. This study reveals novel mechanisms for appetite regulation and energy metabolism that could be essential for desert rodents to survive in xeric environments.

  17. CO2 AND O3 ALTER PHOTOSYNTHESIS AND WATER VAPOR EXCHANGE FOR PINUS PONDEROSA NEEDLES

    Science.gov (United States)

    1. Effects of CO2 and O3 were determined for a key component of ecosystem carbon and water cycling: needle gas exchange (photosynthesis, conductance, transpiration and water use efficiency). The measurements were made on Pinus ponderosa seedlings grown in outdoor, sunlit, mesoc...

  18. Examining the Effects of Altered Water Quality on Sea Urchin Fertilization Success and Embryo Development

    Science.gov (United States)

    Haverkort-Yeh, Roxanne Dominique; Tamaru, Clyde S.; Gorospe, Kelvin Dalauta; Rivera, Malia Ana J.

    2013-01-01

    As a result of shifting marine environmental conditions caused by global climate change and localized water pollution, marine organisms are becoming increasingly exposed to changing water quality conditions. For example, they are exposed to more extreme salinity fluctuations as a result of heavier rainfall, melting polar caps, or extreme droughts.…

  19. Effect of free and symbiotic nitrogen fixing bacterial co-inoculation on seed and seedling of soybean seeds produced under deficit water condition

    Directory of Open Access Journals (Sweden)

    Hamed Hadi

    2016-04-01

    Full Text Available Effect of free and symbiotic nitrogen fixing bacteria on seed and seedling produced seeds under deficit irrigation was conducted in laboratory and field experiments in 2006. In laboratory of karaj’s Seed and Plant Research and Certificate Institute an experiment was conducted based on factorial in form of completely randomized design with four replications and in field’s of Islamic Azad University, Varamin Branch were split factorial in form of randomized completely block design with three replications. Treatments included water stress [Irrigation after 50 (Normal irrigation, 100 (Middle stress, 150 (Severe stress mm evaporation from pan class A], Cultivar [Manokin & Williams and SRF×T3 Line] and inoculation [Inoculation with Bradyrhizobium japonicum, Bradyrhizobium japonicum co-inoculated with Azotobacter chroococcum, No seed inoculation]. Results showed that drought stress decreased the uniformity and germination speed and seedling emergence. Bacteria increased leaf dry weight, stem dry weight, leaf area and seedling vigor index but had no effect on emergence. In irrigation levels inoculated treatments had higher seedling length, leaf, stem, seedling dry weight and seedling vigor. Severs stress seeds inoculated with Bradyrhizobium japonicum had higher root dry weight than control. Therefore in seeds which were produced under deficit irrigation conditions, bacteria increased seedlings vigor.

  20. The Effect of Chemical, Biological and Organic Nutritional Treatments on Sunflowers Yield and Yield Components under the Influence of Water Deficit Stress

    Directory of Open Access Journals (Sweden)

    fatemeh soleymani

    2016-07-01

    Full Text Available Introduction To achieve the higher economic yield of crop plants, supplying enough nutrients to plants is very important. Moreover, nutrient uptakes by plants is influenced by the soil water contents. However, nowadays chemical fertilizer application is important agronomic factor that has significant effects on growth and quantity and quality of final yield, but traditional nutrient management and excessive use of chemical fertilizers may cause the environmental problems such as contamination of soil and water resources, low quality of agricultural products and reduction of soil fertility. These factors have drawn attention to health and ecological sustainable farming systems (Sharma, 2002. In this context, usage of organic and biological products for plant nutrition is considered as one of the solutions to achieve the goals of sustainable agriculture. Materials and methods To evaluate the effect of various feeding systems on yield and yield components of sunflower (Helianthus annuus L. under the influence of water deficit stress, a split-plot experiment based on randomized complete block design with three replications, was carried out in the Agricultural Faculty of Bu-Ali Sina University during the growing season of 2013-2014. Main plots consisted of two irrigation levels: optimum irrigation and deficit irrigation stress (irrigation after 60 and 120 mm evaporation from evaporation pan, class A, respectively and sub-plots included of nine nutrition systems: 1- no bio or chemical fertilizer application, 2- 100% of the recommended chemical fertilizer , 3- vermicompost, 4- phospho nitro kara, 5- vermicompost+ phospho nitro kara, 6- vermicompost+ ½ chemical fertilizer, 7- phospho nitro kara+ ½ chemical fertilizer, 8- vermicompost+ phospho nitro kara+ ½ chemical fertilizer, 9- ½ proposed chemical fertilizer. Phospho-nitro-kara which contains phosphate solubilizing and nitrogen fixing bacteria (Bacillus coagulans, azotobactr chroocuccum and

  1. Effects of elevated CO2 on predator avoidance behaviour by reef fishes is not altered by experimental test water

    Directory of Open Access Journals (Sweden)

    Philip L. Munday

    2016-10-01

    Full Text Available Pioneering studies into the effects of elevated CO2 on the behaviour of reef fishes often tested high-CO2 reared fish using control water in the test arena. While subsequent studies using rearing treatment water (control or high CO2 in the test arena have confirmed the effects of high CO2 on a range of reef fish behaviours, a further investigation into the use of different test water in the experimental arena is warranted. Here, we used a fully factorial design to test the effect of rearing treatment water (control or high CO2 and experimental test water (control or high CO2 on antipredator responses of larval reef fishes. We tested antipredator behaviour in larval clownfish Amphiprion percula and ambon damselfish Pomacentrus amboinensis, two species that have been used in previous high CO2 experiments. Specifically, we tested if: (1 using control or high CO2 water in a two channel flume influenced the response of larval clownfish to predator odour; and (2 using control or high CO2 water in the test arena influenced the escape response of larval damselfish to a startle stimulus. Finally, (3 because the effects of high CO2 on fish behaviour appear to be caused by altered function of the GABA-A neurotransmitter we tested if antipredator behaviours were restored in clownfish treated with a GABA antagonist (gabazine in high CO2 water. Larval clownfish reared from hatching in control water (496 µatm strongly avoided predator cue whereas larval clownfish reared from hatching in high CO2 (1,022 µatm were attracted to the predator cue, as has been reported in previous studies. There was no effect on fish responses of using either control or high CO2 water in the flume. Larval damselfish reared for four days in high CO2 (1,051 µatm exhibited a slower response to a startle stimulus and slower escape speed compared with fish reared in control conditions (464 µatm. There was no effect of test water on escape responses. Treatment of high-CO2 reared

  2. Alteration of natural (37)Ar activity concentration in the subsurface by gas transport and water infiltration.

    Science.gov (United States)

    Guillon, Sophie; Sun, Yunwei; Purtschert, Roland; Raghoo, Lauren; Pili, Eric; Carrigan, Charles R

    2016-05-01

    High (37)Ar activity concentration in soil gas is proposed as a key evidence for the detection of underground nuclear explosion by the Comprehensive Nuclear Test-Ban Treaty. However, such a detection is challenged by the natural background of (37)Ar in the subsurface, mainly due to Ca activation by cosmic rays. A better understanding and improved capability to predict (37)Ar activity concentration in the subsurface and its spatial and temporal variability is thus required. A numerical model integrating (37)Ar production and transport in the subsurface is developed, including variable soil water content and water infiltration at the surface. A parameterized equation for (37)Ar production in the first 15 m below the surface is studied, taking into account the major production reactions and the moderation effect of soil water content. Using sensitivity analysis and uncertainty quantification, a realistic and comprehensive probability distribution of natural (37)Ar activity concentrations in soil gas is proposed, including the effects of water infiltration. Site location and soil composition are identified as the parameters allowing for a most effective reduction of the possible range of (37)Ar activity concentrations. The influence of soil water content on (37)Ar production is shown to be negligible to first order, while (37)Ar activity concentration in soil gas and its temporal variability appear to be strongly influenced by transient water infiltration events. These results will be used as a basis for practical CTBTO concepts of operation during an OSI. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Nutritional deficit and Long Term Potentiation alterations

    Directory of Open Access Journals (Sweden)

    M. Petrosino

    2009-01-01

    Full Text Available In the present work we examined the ability of prenatally malnourished offspring to produce and maintain long-term potentiation (LTP of the perforant path/dentate granule cell synapse in freely moving rats at 15,30, and 90 days of age. Population spike amplitude (PSA was calculated from dentate field potential recordings prior to and at 15, 30, 60 min. and 3, 5, 18 and 24 h following tetanization of the perforant pathway. All animals of both malnourished and well-nourished diet groups at 15 days of age showed potentiation of PSA measures but the measures obtained from 15-day-old prenatally malnourished animals were significantly less than that of age-matched, well-nourished controls. At 30 days of age, remarkable effect of tetanization was likely observed from PSA measures for this age group followed much the same pattern. At 90 days of age, PSA measures obtained from malnourished animals decreased from pretetanization levels immediately following tetanization. At this age, however, at three hours time recordings, this measure growing up to a level which did not differ significantly from that of the control group. These results indicate that the width of tetanization induced enhancement of dentate granule cell response in preweanling rats (15-day-old animals is signifacantly affected fromgestational protein malnutrition and this trend is kept in animals tested at 30 and 90 days of age. The fact, however, that considerable limitation in LTP generation was gained from prenatally malnourished animals at 90 days of age, implying that dietary rehabilitation starting at birth is an intervention strategy not capable to imbrove the effects of the gestational stress.

  4. Quantitative monitoring of sucrose, reducing sugar and total sugar dynamics for phenotyping of water-deficit stress tolerance in rice through spectroscopy and chemometrics

    Science.gov (United States)

    Das, Bappa; Sahoo, Rabi N.; Pargal, Sourabh; Krishna, Gopal; Verma, Rakesh; Chinnusamy, Viswanathan; Sehgal, Vinay K.; Gupta, Vinod K.; Dash, Sushanta K.; Swain, Padmini

    2018-03-01

    In the present investigation, the changes in sucrose, reducing and total sugar content due to water-deficit stress in rice leaves were modeled using visible, near infrared (VNIR) and shortwave infrared (SWIR) spectroscopy. The objectives of the study were to identify the best vegetation indices and suitable multivariate technique based on precise analysis of hyperspectral data (350 to 2500 nm) and sucrose, reducing sugar and total sugar content measured at different stress levels from 16 different rice genotypes. Spectral data analysis was done to identify suitable spectral indices and models for sucrose estimation. Novel spectral indices in near infrared (NIR) range viz. ratio spectral index (RSI) and normalised difference spectral indices (NDSI) sensitive to sucrose, reducing sugar and total sugar content were identified which were subsequently calibrated and validated. The RSI and NDSI models had R2 values of 0.65, 0.71 and 0.67; RPD values of 1.68, 1.95 and 1.66 for sucrose, reducing sugar and total sugar, respectively for validation dataset. Different multivariate spectral models such as artificial neural network (ANN), multivariate adaptive regression splines (MARS), multiple linear regression (MLR), partial least square regression (PLSR), random forest regression (RFR) and support vector machine regression (SVMR) were also evaluated. The best performing multivariate models for sucrose, reducing sugars and total sugars were found to be, MARS, ANN and MARS, respectively with respect to RPD values of 2.08, 2.44, and 1.93. Results indicated that VNIR and SWIR spectroscopy combined with multivariate calibration can be used as a reliable alternative to conventional methods for measurement of sucrose, reducing sugars and total sugars of rice under water-deficit stress as this technique is fast, economic, and noninvasive.

  5. Climatic change and variability: The effects of an altered water regime on Great Lakes coastal wetlands

    International Nuclear Information System (INIS)

    Mortsch, L.

    1990-01-01

    Wetlands of Canada are disappearing at a rapid rate due to urban encroachment and agricultural land drainage. Climatic change may be another threat to their continued viability. Wetlands perform numerous functions such as providing wildlife habitat, enhancing water quality, providing recreation opportunities and supporting commercial activities. Impact scenarios of global warming on Great Lakes hydrology and wetland ecosystem response to water level changes are tabulated. Wetland response to lower annual water levels depends on the type of wetland, its geomorphology and bathymetry. Marshes and open water wetland adapt more readily to lower levels than swamps. Swamps are less resilient since trees cannot regenerate and colonize quickly. Enclosed and barrier beach wetlands are more prone to drying out and loosing wetland vegetation during low water periods. In open shoreline wetlands, the areal extent could increase if there is a gentle slope and other suitable conditions. Precambrian Shield wetlands are located in areas of irregular slope and rocky substrate, and would have fewer sites for successful colonization. 15 refs., 2 tabs

  6. Alterations to throughfall water and solute flux by Tillandsias usneoides L. (Spanish moss) cover in a maritime live oak forest

    Science.gov (United States)

    Gay, T. E.; Van Stan, J. T., II; Reichard, J. S.; Moore, L. D.; Lewis, E. S.

    2014-12-01

    Alterations to forest canopy structures can have a direct effect on hydrological and biogeochemical cycles in forest ecosystems. Epiphytes act as additional canopy biomass intercepting water, effecting pathways under different micrometeorological conditions and alternating nutrient uptake/releases. Most studies on epiphyte cover have focused on non-vascular epiphytes (e.g., lichen and bryophyte mosses), leaving vascular epiphytes like Tillandsia usneoides L. (Spanish moss) relatively understudied. To fill this gap, we characterized alterations to throughfall water and dissolved ion enrichment/flux to soils by T. usneoides in a Quercus Virginiana Mill. (southern live oak) stand on St. Catherine's Island. Specifically, we compare throughfall generated from heavy T. usneoides coverage, bare canopy, and a continuum of T. usneoides cover percentages (~400 water & 210 chemistry observations over ~40 storms for each canopy cover category). Findings show T.usneoides acts as a significant water storage agent, significantly reducing throughfall. However, under certain meteorological conditions T. usneoides can become saturated and act as a funneling "hotspot." Tillandsia usneoides coverage enriched throughfall with primarily dry deposited ions (Na+,Cl-, SO42-, Li+), leached greater Mg2+, Ca2+, reduced NO3- and increased NH4+ concentrations. Dry deposited ion enrichment is likely a result of the moss' greater surface roughness. It has been shown that epiphytes prefer to leach Mg2+ and Ca2+. Increased NH4+ suggests that the saturated T. usneoides mat likely hosts microbial decomposition of leaf, branch, and bark biomass ensnared in the plant itself. K-means cluster analysis on the storms revealed 4 storm types of the differing meteorological conditions (windy/calm, dry/wet [high/low VPD], high/low intensity, intermittent/consistent), and these throughfall dynamics varied between these storm types. Discussion of future research questions regarding how these throughfall

  7. Quantifying runoff water quality characteristics from nurseries and avocado groves subjected to altered irrigation and fertilizer regimes

    Science.gov (United States)

    Samant, S. A.; Beighley, R. E.

    2007-12-01

    In agriculture, improper, excessive or poorly timed irrigation and fertilizer applications can result in increased pollutants in runoff and degraded water quality. Specifically, the cultivation of salt sensitive plants and nurseries require significant irrigation and fertilizer that leads to high nutrient leaching. In southern California, a large producer of Avocados and nursery plant, waterways are often subjected to elevated nutrient concentrations, which stress the aquatic ecosystem. In this research, the specific objectives are to determine optimal irrigation and fertilizer application rates for minimizing nutrient and sediment export from avocado groves and nurseries. Altered irrigation and fertilizer application experiments will be implemented and monitored at the San Diego State University's Santa Margarita Ecological Reserve, which contains a 12 ha avocado grove and newly constructed 0.4 ha nursery. The study will last for twelve months, with runoff from natural rainfall or irrigation sampled and analyzed for nutrient concentrations on a monthly basis. The growth rate, leaf nutrient content and plant yield will also be monitored monthly. The nursery site is divided into eight plots (13.5-m x 13.5-m), with each plot containing 1200 plants consisting of four commonly used landscaping varieties in southern California. The avocado grove of the Hass variety is divided into four 1-ha plots. The experimental plots represent combinations of irrigation and fertilization practices with different methods and rates. In all cases, irrigation is fully automated based on soil moisture. To assess the effectiveness of the altered irrigation and fertilizer strategies, runoff water quality and plant yield will be compared to controlled treatments. This research is intended to provide a better understanding of how irrigation and fertilizer management can be used for the long-term reduction of nutrients in the Santa Margarita Watershed, which in turn will lead to improved

  8. Selenium Supplementation Affects Physiological and Biochemical Processes to Improve Fodder Yield and Quality of Maize (Zea mays L.) under Water Deficit Conditions

    Science.gov (United States)

    Nawaz, Fahim; Naeem, Muhammad; Ashraf, Muhammad Y.; Tahir, Muhammad N.; Zulfiqar, Bilal; Salahuddin, Muhammad; Shabbir, Rana N.; Aslam, Muhammad

    2016-01-01

    Climate change is one of the most complex challenges that pose serious threats to livelihoods of poor people who rely heavily on agriculture and livestock particularly in climate-sensitive developing countries of the world. The negative effects of water scarcity, due to climate change, are not limited to productivity food crops but have far-reaching consequences on livestock feed production systems. Selenium (Se) is considered essential for animal health and has also been reported to counteract various abiotic stresses in plants, however, understanding of Se regulated mechanisms for improving nutritional status of fodder crops remains elusive. We report the effects of exogenous selenium supply on physiological and biochemical processes that may influence green fodder yield and quality of maize (Zea mays L.) under drought stress conditions. The plants were grown in lysimeter tanks under natural conditions and were subjected to normal (100% field capacity) and water stress (60% field capacity) conditions. Foliar spray of Se was carried out before the start of tasseling stage (65 days after sowing) and was repeated after 1 week, whereas, water spray was used as a control. Drought stress markedly reduced the water status, pigments and green fodder yield and resulted in low forage quality in water stressed maize plants. Nevertheless, exogenous Se application at 40 mg L-1 resulted in less negative leaf water potential (41%) and enhanced relative water contents (30%), total chlorophyll (53%), carotenoid contents (60%), accumulation of total free amino acids (40%) and activities of superoxide dismutase (53%), catalase (30%), peroxidase (27%), and ascorbate peroxidase (27%) with respect to control under water deficit conditions. Consequently, Se regulated processes improved fodder yield (15%) and increased crude protein (47%), fiber (10%), nitrogen free extract (10%) and Se content (36%) but did not affect crude ash content in water stressed maize plants. We propose that Se

  9. Selenium Supplementation Affects Physiological and Biochemical Processes to Improve Fodder Yield and Quality of Maize (Zea mays L.) under Water Deficit Conditions.

    Science.gov (United States)

    Nawaz, Fahim; Naeem, Muhammad; Ashraf, Muhammad Y; Tahir, Muhammad N; Zulfiqar, Bilal; Salahuddin, Muhammad; Shabbir, Rana N; Aslam, Muhammad

    2016-01-01

    Climate change is one of the most complex challenges that pose serious threats to livelihoods of poor people who rely heavily on agriculture and livestock particularly in climate-sensitive developing countries of the world. The negative effects of water scarcity, due to climate change, are not limited to productivity food crops but have far-reaching consequences on livestock feed production systems. Selenium (Se) is considered essential for animal health and has also been reported to counteract various abiotic stresses in plants, however, understanding of Se regulated mechanisms for improving nutritional status of fodder crops remains elusive. We report the effects of exogenous selenium supply on physiological and biochemical processes that may influence green fodder yield and quality of maize ( Zea mays L.) under drought stress conditions. The plants were grown in lysimeter tanks under natural conditions and were subjected to normal (100% field capacity) and water stress (60% field capacity) conditions. Foliar spray of Se was carried out before the start of tasseling stage (65 days after sowing) and was repeated after 1 week, whereas, water spray was used as a control. Drought stress markedly reduced the water status, pigments and green fodder yield and resulted in low forage quality in water stressed maize plants. Nevertheless, exogenous Se application at 40 mg L -1 resulted in less negative leaf water potential (41%) and enhanced relative water contents (30%), total chlorophyll (53%), carotenoid contents (60%), accumulation of total free amino acids (40%) and activities of superoxide dismutase (53%), catalase (30%), peroxidase (27%), and ascorbate peroxidase (27%) with respect to control under water deficit conditions. Consequently, Se regulated processes improved fodder yield (15%) and increased crude protein (47%), fiber (10%), nitrogen free extract (10%) and Se content (36%) but did not affect crude ash content in water stressed maize plants. We propose that

  10. Selenium Supplementation Affects Physiological and Biochemical Processes to Improve Fodder Yield and Quality of Maize (Zea mays L. under Water Deficit Conditions

    Directory of Open Access Journals (Sweden)

    Fahim Nawaz

    2016-09-01

    Full Text Available Climate change is one of the most complex challenges that pose serious threats to livelihoods of poor people who rely heavily on agriculture and livestock particularly in climate-sensitive developing countries of the world. The negative effects of water scarcity, due to climate change, are not limited to productivity food crops but have far-reaching consequences on livestock feed production systems. Selenium (Se is considered essential for animal health and has also been reported to counteract various abiotic stresses in plants however, understanding of Se regulated mechanisms for improving nutritional status of fodder crops remains elusive. We report the effects of exogenous selenium (Se supply on physiological and biochemical processes that may influence green fodder yield and quality of maize (Zea mays L. under drought stress conditions. The plants were grown in lysimeter tanks under natural conditions and were subjected to normal (100% field capacity and water stress (60% field capacity conditions. Foliar spray of Se was carried out before the start of tasseling stage (65 days after sowing and was repeated after one week, whereas water spray was used as a control. Drought stress markedly reduced the water status, pigments and green fodder yield and resulted in low forage quality in water stressed maize plants. Nevertheless, exogenous Se application at 40 mg L-1 resulted in less negative leaf water potential (41% and enhanced relative water contents (30%, total chlorophyll (53%, carotenoid contents (60%, accumulation of total free amino acids (40% and activities of superoxide dismutase (53%, catalase (30%, peroxidase (27% and ascorbate peroxidase (27% with respect to control under water deficit conditions. Consequently, Se regulated processes improved fodder yield (15% and increased crude protein (47%, fibre (10%, nitrogen free extract (10% and Se content (36% but did not affect crude ash content in water stressed maize plants. We propose

  11. Theoretical modeling of heating and structure alterations in cartilage under laser radiation with regard to water evaporation and diffusion dominance

    Science.gov (United States)

    Sobol, Emil N.; Kitai, Moishe S.; Jones, Nicholas; Sviridov, Alexander P.; Milner, Thomas E.; Wong, Brian

    1998-05-01

    We develop a theoretical model to calculate the temperature field and the size of modified structure area in cartilaginous tissue. The model incorporates both thermal and mass transfer in a tissue regarding bulk absorption of laser radiation, water evaporation from a surface and temperature dependence of diffusion coefficient. It is proposed that due to bound- to free-phase transition of water in cartilage heated to about 70 degrees Celsius, some parts of cartilage matrix (proteoglycan units) became more mobile. The movement of these units takes place only when temperature exceed 70 degrees Celsius and results in alteration of tissue structure (denaturation). It is shown that (1) the maximal temperature is reached not on the surface irradiated at some distance from the surface; (2) surface temperature reaches a plateau quicker that the maximal temperature; (3) the depth of denatured area strongly depends on laser fluence and wavelength, exposure time and thickness of cartilage. The model allows to predict and control temperature and depth of structure alterations in the course of laser reshaping and treatment of cartilage.

  12. Endocrine modulation, inhibition of ovarian development and hepatic alterations in rainbow trout exposed to polluted river water

    Energy Technology Data Exchange (ETDEWEB)

    Vigano, Luigi, E-mail: vigano@irsa.cnr.i [Water Research Institute, National Council of Research, Brugherio, Milan (Italy); Benfenati, Emilio [Mario Negri Institute, Laboratory of Environmental Chemistry and Toxicology, Milan (Italy); Bottero, Sergio; Cevasco, Alessandra; Monteverde, Martino; Mandich, Alberta [Department of Environmental, Experimental and Applied Biology, University of Genoa, Genoa (Italy)

    2010-12-15

    Under laboratory conditions, female rainbow trout were exposed to graded concentrations of water from the River Lambro, a polluted tributary of the River Po, and to the effluent of a large wastewater treatment plant which flows into the River Lambro. In field exposures, trout were held in cages in the River Po upstream and downstream from the confluence of the River Lambro. After 10-day (laboratory) and 30-day (laboratory and field) exposures, trout were examined for several chemical, biochemical and histological endpoints. The results indicated that exposure to complex mixtures of chemicals, including estrogen receptor agonists, aryl-hydrocarbon receptor agonists, and probably antiandrogens, had occurred. Exposure altered the plasma levels of 17{beta}-estradiol and testosterone, and some treatments also enhanced the activity of hepatic ethoxyresorufin O-deethylase. Gonadal histology showed varying levels of degenerative processes characterised by oocyte atresia, haemorrhages, melano-macrophage centres (MMCs), and oogonia proliferation. Liver histology showed less severe effects. - This study examined the progression of hormonal and gonadal alterations in female trout exposed to river water from an area known to affect resident fish species.

  13. Endocrine modulation, inhibition of ovarian development and hepatic alterations in rainbow trout exposed to polluted river water

    International Nuclear Information System (INIS)

    Vigano, Luigi; Benfenati, Emilio; Bottero, Sergio; Cevasco, Alessandra; Monteverde, Martino; Mandich, Alberta

    2010-01-01

    Under laboratory conditions, female rainbow trout were exposed to graded concentrations of water from the River Lambro, a polluted tributary of the River Po, and to the effluent of a large wastewater treatment plant which flows into the River Lambro. In field exposures, trout were held in cages in the River Po upstream and downstream from the confluence of the River Lambro. After 10-day (laboratory) and 30-day (laboratory and field) exposures, trout were examined for several chemical, biochemical and histological endpoints. The results indicated that exposure to complex mixtures of chemicals, including estrogen receptor agonists, aryl-hydrocarbon receptor agonists, and probably antiandrogens, had occurred. Exposure altered the plasma levels of 17β-estradiol and testosterone, and some treatments also enhanced the activity of hepatic ethoxyresorufin O-deethylase. Gonadal histology showed varying levels of degenerative processes characterised by oocyte atresia, haemorrhages, melano-macrophage centres (MMCs), and oogonia proliferation. Liver histology showed less severe effects. - This study examined the progression of hormonal and gonadal alterations in female trout exposed to river water from an area known to affect resident fish species.

  14. Multiple-endpoints gene alteration-based (MEGA) assay: A toxicogenomics approach for water quality assessment of wastewater effluents.

    Science.gov (United States)

    Fukushima, Toshikazu; Hara-Yamamura, Hiroe; Nakashima, Koji; Tan, Lea Chua; Okabe, Satoshi

    2017-12-01

    Wastewater effluents contain a significant number of toxic contaminants, which, even at low concentrations, display a wide variety of toxic actions. In this study, we developed a multiple-endpoints gene alteration-based (MEGA) assay, a real-time PCR-based transcriptomic analysis, to assess the water quality of wastewater effluents for human health risk assessment and management. Twenty-one genes from the human hepatoblastoma cell line (HepG2), covering the basic health-relevant stress responses such as response to xenobiotics, genotoxicity, and cytotoxicity, were selected and incorporated into the MEGA assay. The genes related to the p53-mediated DNA damage response and cytochrome P450 were selected as markers for genotoxicity and response to xenobiotics, respectively. Additionally, the genes that were dose-dependently regulated by exposure to the wastewater effluents were chosen as markers for cytotoxicity. The alterations in the expression of an individual gene, induced by exposure to the wastewater effluents, were evaluated by real-time PCR and the results were validated by genotoxicity (e.g., comet assay) and cell-based cytotoxicity tests. In summary, the MEGA assay is a real-time PCR-based assay that targets cellular responses to contaminants present in wastewater effluents at the transcriptional level; it is rapid, cost-effective, and high-throughput and can thus complement any chemical analysis for water quality assessment and management. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Influence of natural and synthetic vitamin C (ascorbic acid) on primary and secondary metabolites and associated metabolism in quinoa (Chenopodium quinoa Willd.) plants under water deficit regimes.

    Science.gov (United States)

    Aziz, Aniqa; Akram, Nudrat Aisha; Ashraf, Muhammad

    2018-02-01

    Phytoextracts are being widely used these days as a source of bioactive compounds for mitigating the harmful effects of abiotic stresses including drought stress. In this study, it was assessed how far foliar applied pure synthetic ascorbic acid (AsA) or natural sweet orange juice (OJ) enriched with AsA could mitigate the drought stress induced adverse effects on growth and some key metabolic processes in quinoa (Chenopodium quinoa Willd.; cultivar V 9 ) plants. Two weeks old quinoa seedlings were subjected to varying irrigation regimes as control [100% field capacity (FC)] and drought stress (60% FC, 40% FC and 20% FC). After one month of water deficit treatments, various levels of ascorbic acid (150 mg L -1 AsA or 25% OJ) besides control [distilled water (DW) and no spray (NS)] were applied as a foliar spray. After 15 days of AsA application, different physio-biochemical attributes were measured. The results showed that water deficit markedly decreased plant growth, relative water content (RWC), photosynthetic rate, total carotenoids (CAR) and total flavonoids, while it increased relative membrane permeability (RMP), intrinsic AsA content, hydrogen peroxide (H 2 O 2 ), malondialdehyde (MDA), glycinebetaine (GB), total phenolics, total soluble proteins (TSP), total free amino acids, activities of key antioxidant enzymes [superoxide dismutase (SOD), peroxidase (POD)], total soluble sugars (TSS), reducing (RS) and non-reducing sugars (NRS). Most obvious results of most of these parameters were observed at 40% and 20% FC. Foliar-applied pure 150 mg L -1 AsA and 25% OJ were found to be very effective in improving plant growth, RMP, photosynthetic rate, CAR, proline, AsA, MDA, GB, TSP, free amino acids, SOD, POD, TSS, RS, NRS and total flavonoids. It was noticed that 25% OJ enriched with AsA and other essential nutrients and biomolecules was as efficient as 150 mg L -1 AsA in reducing the adverse effects of drought stress on quinoa plants. So, it was concluded

  16. water alteration processes and kinetics of basaltic glasses, natural analogue of nuclear glasses

    International Nuclear Information System (INIS)

    Techer, I.; Advocat, Th.; Vernaz, E.; Lancelot, J.R.; Liotard, J.M.

    1997-01-01

    Dissolution experiments of a basaltic glass were carried out at 90 deg C for different reaction progresses. The initial dissolution rate was compared with values obtained for rhyolitic glass and the R7T7 nuclear glass. The activation energy was also determined by computing literature data. The results provide similar reactional mechanism for basaltic and nuclear glasses. Dissolution rates measured under saturation conditions were compared to theoretical dissolution rates. These ones were calculated using two kinetic models: the first rate equation is the Grambow's law which only takes into account ortho-silica acid activity; the second rate equation was proposed by Daux et al., where silica and aluminum are combined to formulate the affinity. The comparison between experimental and theoretical results point out that these two models are not appropriate to describe the alteration kinetic of basaltic glasses. (authors)

  17. Urbanization dramatically altered the water balances of a paddy field dominated basin in southern China

    Science.gov (United States)

    L. Hao; G. Sun; Y. Liu; J. Wan; M. Qin; H. Qian; C. Liu; R. John; P. Fan; J. Chen

    2015-01-01

    Rice paddy fields provide important ecosystem services (e.g., food production, water retention, carbon sequestration) to a large population globally. However, these benefits are declining as a result of rapid environmental and socioeconomic transformations characterized by population growth, urbanization, and climate change in many Asian countries. This case study...

  18. Storms do not alter long-term watershed development influences on coastal water quality

    Science.gov (United States)

    A twelve year (2000 − 2011) study of three coastal lagoons in the Gulf of Mexico was conducted to assess the impacts of local watershed development and tropical storms on water quality. The lagoons have similar physical and hydrological characteristics, but differ substantially i...

  19. Flow Alteration and Chemical Reduction: Air Stripping to Lessen Subsurface Discharges of Mercury to Surface Water

    Science.gov (United States)

    Brooks, S. C.; Bogle, M.; Liang, L.; Miller, C. L.; Peterson, M.; Southworth, G. R.; Spalding, B. P.

    2009-12-01

    Mercury concentrations in groundwater, surface water, and biota near an industrial facility in Oak Ridge, Tennessee remain high some 50 years after the original major releases from the facility to the environment. Since the mid-1980s, various remedial and abatement actions have been implemented at the facility, including re-routing water flows, armoring contaminated stream banks, relining or cleanout of facility storm drains, and activated charcoal treatment of groundwater and sump discharges. These actions were taken to reduce inorganic mercury inputs from the facility to the stream; a strategy that assumes limiting the inorganic mercury precursor will reduce Hg methylation and its subsequent bioaccumulation. To date, such actions have reduced mercury loading from the site by approximately 90% from levels typical of the mid 1980's, but waterborne mercury at the facility boundary remains roughly 100 times the typical local background concentration and methylmercury accumulation in aquatic biota exceed standards for safe consumption by humans and wildlife. In 2008 and 2009, a series of investigations was initiated to explore innovative approaches to further control mercury concentrations in stream water. Efforts in this study focused on decreasing waterborne inorganic mercury inputs from two sources. The first, a highly localized source, is the discharge point of the enclosed stormdrain network whereas the second is a more diffuse short reach of stream where metallic Hg in streambed sediments generates a continued input of dissolved Hg to the overlying water. Moving a clean water flow management discharge point to a position downstream of the contaminated reach reduced mercury loading from the streambed source by 75% - 100%, likely by minimizing resuspension of Hg-rich fine particulates and changing characteristic hyporheic flow path length and residence time. Mercury in the stormdrain discharge exists as highly reactive dissolved Hg(II) due to residual chlorine in

  20. A multi-disciplinary approach for the integrated assessment of water alterations under climate change

    Science.gov (United States)

    Sperotto, Anna; Torresan, Silvia; Molina, Jose Luis; Pulido Velazquez, Manuel; Critto, Andrea; Marcomini, Antonio

    2017-04-01

    Understanding the co-evolution and interrelations between natural and human pressures on water systems is required to ensure a sustainable management of resources under uncertain climate change conditions. To pursue multi-disciplinary research is therefore necessary to consider the multiplicity of stressors affecting water resources, take into account alternative perspectives (i.e. social, economic and environmental objective and priorities) and deal with uncertainty which characterize climate change scenarios. However, approaches commonly adopted in water quality assessment are predominantly mono-disciplinary, single-stressors oriented and apply concepts and models specific of different academic disciplines (e.g. physics, hydrology, ecology, sociology, economy) which, in fact, seldom shed their conceptual blinders failing to provide truly integrated results. In this context, the paper discusses the benefits and limits of adopting a multi-disciplinary approach where different knowledge domains collaborate and quantitative and qualitative information, coming from multiple conceptual and model-based research, are integrated in a harmonic manner. Specifically, Bayesian Networks are used as meta-modelling tool for structuring and combining the probabilistic information available in existing hydrological models, climate change and land use projections, historical observations and expert opinion. The developed network allows to perform a stochastic multi-risk assessment considering the interlacing between climate (i.e. irregularities in water regime) and land use changes (i.e. agriculture, urbanization) and their cascading impacts on water quality parameters (i.e. nutrients loadings). Main objective of the model is the development of multi-risk scenarios to assess and communicate the probability of not meeting a "Good chemical water status" over future timeframe taking into account projected climatic and not climatic conditions. The outcomes are finally used to identify

  1. Resposta de porta-enxertos de citros ao déficit hídrico Response of citrus rootstocks to water deficit

    Directory of Open Access Journals (Sweden)

    Elaine Costa Cerqueira

    2004-12-01

    a 6 x 9 factorial, with six genotypes and nine period of evaluations. The evaluations followed the sequence: irrigation, water deficit, and irrigation when the plants had two to three leaves pairs. It was analyzed the variables root dry matter, dry matter of above ground parts, plant water potential, and leaf transpiration. For the above ground dry matter the genotypes Volkamer lemon and Sour orange showed decrease during the water deficit condition. The other genotypes showed no significant differences for this variable. Without irrigation, all genotypes decreased in their water potentials. The hybrids kept it unchanged maintaining increased transpiration rates. The hybrids HTR - 051, and TSK x CTTR - 017 presented the best performances for all variables studied being more promising as rootstocks for water deficit conditions.

  2. Influence of water deficit on the molecular responses of Pinus contorta × Pinus banksiana mature trees to infection by the mountain pine beetle fungal associate, Grosmannia clavigera.

    Science.gov (United States)

    Arango-Velez, Adriana; González, Leonardo M Galindo; Meents, Miranda J; El Kayal, Walid; Cooke, Barry J; Linsky, Jean; Lusebrink, Inka; Cooke, Janice E K

    2014-11-01

    Conifers exhibit a number of constitutive and induced mechanisms to defend against attack by pests and pathogens such as mountain pine beetle (Dendroctonus ponderosae Hopkins) and their fungal associates. Ecological studies have demonstrated that stressed trees are more susceptible to attack by mountain pine beetle than their healthy counterparts. In this study, we tested the hypothesis that water deficit affects constitutive and induced responses of mature lodgepole pine × jack pine hybrids (Pinus contorta Dougl. ex Loud. var. latifolia Engelm. ex S. Wats. × Pinus banksiana Lamb.) to inoculation with the mountain pine beetle fungal associate Grosmannia clavigera (Robinson-Jeffrey and Davidson) Zipfel, de Beer and Wingfield. The degree of stress induced by the imposed water-deficit treatment was sufficient to reduce photosynthesis. Grosmannia clavigera-induced lesions exhibited significantly reduced dimensions in water-deficit trees relative to well-watered trees at 5 weeks after inoculation. Treatment-associated cellular-level changes in secondary phloem were also observed. Quantitative RT-PCR was used to analyze transcript abundance profiles of 18 genes belonging to four families classically associated with biotic and abiotic stress responses: aquaporins (AQPs), dehydration-responsive element binding (DREB), terpene synthases (TPSs) and chitinases (CHIs). Transcript abundance profiles of a TIP2 AQP and a TINY-like DREB decreased significantly in fungus-inoculated trees, but not in response to water deficit. One TPS, Pcb(+)-3-carene synthase, and the Class II CHIs PcbCHI2.1 and PcbCHI2.2 showed increased expression under water-deficit conditions in the absence of fungal inoculation, while another TPS, Pcb(E)-β-farnesene synthase-like, and two CHIs, PcbCHI1.1 and PcbCHI4.1, showed attenuated expression under water-deficit conditions in the presence of fungal inoculation. The effects were observed both locally and systemically. These results demonstrate

  3. Mistletoe infection alters the transpiration flow path and suppresses water regulation of host trees during extreme events

    Science.gov (United States)

    Griebel, A.; Maier, C.; Barton, C. V.; Metzen, D.; Renchon, A.; Boer, M. M.; Pendall, E.

    2017-12-01

    Mistletoe is a globally distributed group of parasitic plants that infiltrates the vascular tissue of its host trees to acquire water, carbon and nutrients, making it a leading agent of biotic disturbance. Many mistletoes occur in water-limited ecosystems, thus mistletoe infection in combination with increased climatic stress may exacerbate water stress and potentially accelerate mortality rates of infected trees during extreme events. This is an emerging problem in Australia, as mistletoe distribution is increasing and clear links between mistletoe infection and mortality have been established. However, direct observations about how mistletoes alter host physiological processes during extreme events are rare, which impedes our understanding of mechanisms underlying increased tree mortality rates. We addressed this gap by continuously monitoring stem and branch sap flow and a range of leaf traits of infected and uninfected trees of two co-occurring eucalypt species during a severe heatwave in south-eastern Australia. We demonstrate that mistletoes' leaf water potentials were maintained 30% lower than hosts' to redirect the trees' transpiration flow path towards mistletoe leaves. Eucalypt leaves reduced water loss through stomatal regulation when atmospheric dryness exceeded 2 kPa, but the magnitude of stomatal regulation in non-infected eucalypts differed by species (between 40-80%). Remarkably, when infected, sap flow rates of stems and branches of both eucalypt species remained unregulated even under extreme atmospheric dryness (>8 kPa). Our observations indicate that excessive water use of mistletoes likely increases xylem cavitation rates in hosts during prolonged droughts and supports that hydraulic failure contributes to increased mortality of infected trees. Hence, in order to accurately model the contribution of biotic disturbances to tree mortality under a changing climate, it will be crucial to increase our process-based understanding of the interaction

  4. Non-invasive imaging using reporter genes altering cellular water permeability

    Science.gov (United States)

    Mukherjee, Arnab; Wu, Di; Davis, Hunter C.; Shapiro, Mikhail G.

    2016-12-01

    Non-invasive imaging of gene expression in live, optically opaque animals is important for multiple applications, including monitoring of genetic circuits and tracking of cell-based therapeutics. Magnetic resonance imaging (MRI) could enable such monitoring with high spatiotemporal resolution. However, existing MRI reporter genes based on metalloproteins or chemical exchange probes are limited by their reliance on metals or relatively low sensitivity. Here we introduce a new class of MRI reporters based on the human water channel aquaporin 1. We show that aquaporin overexpression produces contrast in diffusion-weighted MRI by increasing tissue water diffusivity without affecting viability. Low aquaporin levels or mixed populations comprising as few as 10% aquaporin-expressing cells are sufficient to produce MRI contrast. We characterize this new contrast mechanism through experiments and simulations, and demonstrate its utility in vivo by imaging gene expression in tumours. Our results establish an alternative class of sensitive, metal-free reporter genes for non-invasive imaging.

  5. Cold-water immersion alters muscle recruitment and balance of basketball players during vertical jump landing.

    Science.gov (United States)

    Macedo, Christiane de Souza Guerino; Vicente, Rafael Chagas; Cesário, Mauricio Donini; Guirro, Rinaldo Roberto de Jesus

    2016-01-01

    The purpose of this study was to evaluate the effects of cold-water immersion on the electromyographic (EMG) response of the lower limb and balance during unipodal jump landing. The evaluation comprised 40 individuals (20 basketball players and 20 non-athletes). The EMG response in the lateral gastrocnemius, tibialis anterior, fibular longus, rectus femoris, hamstring and gluteus medius; amplitude and mean speed of the centre of pressure, flight time and ground reaction force (GRF) were analysed. All volunteers remained for 20 min with their ankle immersed in cold-water, and were re-evaluated immediately post and after 10, 20 and 30 min of reheating. The Shapiro-Wilk test, Friedman test and Dunn's post test (P lower for the athletes. Lower jump flight time and GRF, greater amplitude and mean speed of centre of pressure were predominant in the athletes. Cold-water immersion decreased the EMG activity of the lower limb, flight time and GRF and increased the amplitude and mean speed of centre of pressure.

  6. Effect of application of growth regulators on the physiological and yield parameters of winter wheat under water deficit

    Czech Academy of Sciences Publication Activity Database

    Barányiová, I.; Klem, Karel

    2016-01-01

    Roč. 62, č. 3 (2016), s. 114-120 ISSN 1214-1178 R&D Projects: GA MZe QJ1530373 Institutional support: RVO:67179843 Keywords : PSII photochemistry * number of spikes * photosynthesis * spike productivity * water limitation Subject RIV: EH - Ecology, Behaviour Impact factor: 1.225, year: 2016

  7. The sunflower transcription factor HaHB11 confers tolerance to water deficit and salinity to transgenic Arabidopsis and alfalfa plants.

    Science.gov (United States)

    Cabello, Julieta V; Giacomelli, Jorge I; Gómez, María C; Chan, Raquel L

    2017-09-10

    Homeodomain-leucine zipper (HD-Zip) transcription factors are unique to the plant kingdom; members of subfamily I are known to be involved in abiotic stress responses. HaHB11 belongs to this subfamily and it was previously shown that it is able to confer improved yield and tolerance to flooding via a quiescent strategy. Here we show that HaHB11 expression is induced by ABA, NaCl and water deficit in sunflower seedlings and leaves. Arabidopsis transgenic plants expressing HaHB11, controlled either by its own promoter or by the constitutive 35S CaMV, presented rolled leaves and longer roots than WT when grown under standard conditions. In addition, these plants showed wider stems and more vascular bundles. To deal with drought, HaHB11 transgenic plants closed their stomata faster and lost less water than controls, triggering an enhanced tolerance to such stress condition and also to salinity stress. Concomitantly, ABA-synthesis and sensing related genes were differentially regulated in HaHB11 transgenic plants. Either under long-term salinity stress or mild drought stress, HaHB11 transgenic plants did not exhibit yield penalties. Moreover, alfalfa transgenic plants were generated which also showed enhanced drought tolerance. Altogether, the results indicated that HaHB11 was able to confer drought and salinity tolerance via a complex mechanism which involves morphological, physiological and molecular changes. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Sensitivity and tolerance of Riparian arthropod communities to altered water resources along a drying river.

    Science.gov (United States)

    McCluney, Kevin E; Sabo, John L

    2014-01-01

    Rivers around the world are drying with increasing frequency, but little is known about effects on terrestrial animal communities. Previous research along the San Pedro River in southeastern AZ, USA, suggests that changes in the availability of water resources associated with river drying lead to changes in predator abundance, community composition, diversity, and abundance of particular taxa of arthropods, but these observations have not yet been tested manipulatively. In this study, we constructed artificial pools in the stream bed adjacent to a drying section of the San Pedro River and maintained them as the river dried. We compared pitfall trapped arthropods near artificial pools to adjacent control sites where surface waters temporarily dried. Assemblage composition changed differentially at multiple taxonomic levels, resulting in different assemblages at pools than at control sites, with multiple taxa and richness of carabid beetle genera increasing at pools but not at controls that dried. On the other hand, predator biomass, particularly wolf spiders, and diversity of orders and families were consistently higher at control sites that dried. These results suggest an important role for colonization dynamics of pools, as well as the ability of certain taxa, particularly burrowing wolf spiders, to withstand periods of temporary drying. Overall, we found some agreement between this manipulative study of water resources and a previous analysis of river drying that showed shifts in composition, changes in diversity, and declines in abundance of certain taxa (e.g. carabid beetles). However, colonization dynamics of pools, as well as compensatory strategies of predatory wolf spiders seem to have led to patterns that do not match previous research, with control sites maintaining high diversity, despite drying. Tolerance of river drying by some