130 results on '"conductance stomatique"'
Search Results
2. Effect of root infection by <italic>Macrophomina phaseolina</italic> on stomatal conductance, canopy temperature and yield of soybean.
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Doubledee, Micah D., Rupe, John C., Rothrock, Craig S., and Bajwa, Sreekala G.
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MACROPHOMINA phaseolina , *DISEASE resistance of plants , *SOYBEAN , *PLANT physiology , *CULTIVARS - Abstract
Charcoal rot, caused by
Macrophomina phaseolina , is a widespread drought-associated, soilborne disease of soybean. Generally, disease severity is assessed indirectly as host colonization at the end of the growing season. Few studies have measured the effects of disease during the season. Two moderately charcoal rot resistant cultivars (‘DT 97-4290‘ and ‘Delta Pineland 4546‘), a drought tolerant cultivar (‘R01-1581F’) and a susceptible cultivar (‘LS 980358‘) were planted in microplots filled with uninoculated steam pasteurized soil or pasteurized soil infested withM. phaseolina . Half of the plots were irrigated and half were drought stressed. Stomatal conductance and infrared canopy temperatures were measured 47, 70, 77 and 98 days after planting (DAP) in 2008 and 52, 63, 72 and 84 DAP in 2009. Yields were taken at the end of the season. There were significant differences in stomatal conductance. In 2008, stomatal conductance was significantly lower 47 DAP in the non-irrigated/inoculated plots than the other treatments. At 98 DAP, stomatal conductance was highest in the irrigated/non-inoculated plots. In 2009, stomatal conductance was significantly higher in the non-infested plots than the infested plots of ‘LS 890358‘ and ‘R01-1581F’ across sample times, but not in plots of the resistant cultivars ‘DT 97-4290‘ or ‘DPL 4546‘. These differences were reflected in significantly greater canopy temperatures and lower yields in the infested compared with the non-infested plots of the susceptible, but not the resistant cultivars. These results show that root infection byM. phaseolina can reduce water movement in soybean and reduce yields in susceptible cultivars. [ABSTRACT FROM AUTHOR]- Published
- 2018
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3. Leaf-level physiology in four subalpine plants in tephra-impacted forests during drought.
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Watt, Abby J., Fischer, Dylan G., Antos, Joseph A., and Zobel, Donald B.
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CLIMATE change , *CONIFERS , *DROUGHTS , *PHOTOSYNTHESIS - Abstract
Ecological impacts of climate change in the Pacific Northwest may hinge on acclimation to drier summers, highlighting the importance of plant physiological studies in forests. Evaluating dominant forest plant species under old-growth and managed forest conditions is similarly important as timber harvest might change microclimates and alter drought effects on plants. We examined water potential and gas exchange rates of four dominant plant species in understories of subalpine forests of the Pacific Northwest region of the United States during 2015 - a year with drought conditions representative of future climate projections. We examined two conifer species ( Abies amabilis Douglas ex J. Forbes and Tsuga heterophylla (Raf.) Sarg.) and two huckleberry species ( Vaccinium membranaceum Douglas ex Torr. and Vaccinium ovalifolium Sm.) in old-growth and formerly clear-cut forests at two elevations. Contrary to expectations, we found no evidence of hydraulic stress, and there were no significant differences between old-growth and clear-cut stands, consistent with an edaphic buffering effect in this volcanic landscape. Variation in stem elongation rates among years also indicated the lack of a strong drought response in 2015. Water potential, photosynthesis, and stomatal conductance varied among species and among elevations. In combination, our results help constrain expected physiological activity of understory species in subalpine forests and emphasize the importance of the edaphic context (e.g., tephra deposits) in framing expectations for the responses to drought. [ABSTRACT FROM AUTHOR]
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- 2018
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4. Physiological responses to alternative flooding and drought stress episodes in two willow ( Salix spp.) clones.
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Doffo, Guillermo N., Monteoliva, Silvia E., Rodríguez, María E., and Luquez, Virginia M.C.
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DROUGHTS , *WILLOWS , *CLIMATE change , *FLOODS , *PLANT shoots - Abstract
Climate change will increase the occurrence of flash floods as a consequence of extreme rain events, creating alternate periods of drought and flooding during the growing season. We analyzed the responses of two willow clones with contrasting responses to flooding (clone B, Salix matsudana × Salix alba hybrid; clone Y, Salix alba) to different combinations of stress treatments: continuous flooding or drought for six weeks, or cyclic treatments of two weeks of stress separated by two weeks of watering at field capacity. Drought reduced growth, stomatal conductance, and total leaf area in both clones, but flooding did not. Flooding reduced the root to shoot ratio in both clones. The hydraulic conductivity of the main stem was significantly reduced by drought only in clone Y. The area of the vessels was decreased by both drought and flooding, but the number was increased only by drought. The occurrence of drought before flooding reduced the vessel area, but the opposite treatment did not. An episode of drought after one of flooding is more stressful than the opposite situation, especially for clone Y, which could not adjust its water transport capacity during the drought period. [ABSTRACT FROM AUTHOR]
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- 2017
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5. Évaluation du potentiel d'espèces végétales indigènes au site Whabouchi pour la restauration minière
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Roy, Sébastien, Chelo, Chiara, Shipley, Bill, Roy, Sébastien, Chelo, Chiara, and Shipley, Bill
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La re-végétalisation est une pratique au cœur des programmes de restaurations des haldes de stériles et de co-dispositions des terrains miniers. Néanmoins, les essences transplantées subissent une mortalité rapide en raison d’un important stress hydrique. Identifier les espèces végétales les plus aptes à survivre avec cette condition est capital pour limiter le coût et le temps nécessaire à l’élaboration de ces projets. Ce mémoire de maitrise a pour objectif d’évaluer la probabilité de survie de sept espèces indigènes de l’environnement du site minier de Whabouchi en fonction de trois volumes de substrat disponible (100 ml, 1 L et 2 L) et également d’évaluer l’intérêt d’utiliser des traits physiologiques des plantes relatifs au stress hydrique – la photosynthèse nette, la conductance stomatique et l’efficacité d’utilisation en eau – pour estimer la probabilité de survie de ces sept espèces en conditions de stress hydrique. Nous avons émis l’hypothèse que la meilleure probabilité de survie allait être obtenu avec la méthode de plantation utilisant le plus de volume de substrat et que les espèces survivant à la première saison de croissance allait avoir une bonne probabilité de survie à la deuxième saison de croissance. La dernière hypothèse était qu’une faible sensibilité des plantes aux traits physiologiques étudiés en condition de stress hydrique était corrélée à une forte probabilité de survie. Les résultats expérimentaux ont montré que la pochette simple (1 L de substrat) était la méthode de plantation prodiguant la meilleure probabilité de survie pendant la première saison de croissance et que les plantes avec une bonne probabilité de survie à la première saison de croissance avaient effectivement une bonne probabilité de survie à la deuxième saison de croissance. Dans cette dernière la carotte se montre aussi être une bonne méthode de plantation. Aucune corrélation n’a été trouvé entre une faible sensibilité aux traits physiologiques et la probabilité de survie
- Published
- 2021
6. Influence de l’humidité relative sur les aquaporines de Betula pendula
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Ahouanhode, Dominique, Laboratoire de Physique et Physiologie Intégratives de l’Arbre en environnement Fluctuant (PIAF), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Clermont Auvergne (UCA), Université Clermont Auvergne (UCA), FRA., VetAgro Sup, and Aurélie Gousset
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Conductance stomatique ,TIP ,Betula pendula ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,Humidité relative ,PIP - Abstract
Master; Les scénarii de changement climatique pour l’année 2100 prévoient une augmentation de la température de l’air (de 2,3 à 4,5 °C) et des précipitations (de 5 à 30 %) dans la région de la Baltique, une zone où le bouleau (Betula pendula) est une espèce très importante. Ces nombreux changements climatiques pourraient donc impacter significativement la croissance des arbres à feuilles caduques et le fonctionnement des écosystèmes forestiers. Ainsi, dans le but de comprendre le comportement du bouleau face à des modifications d’humidité relative, des analyses écophysiologiques (vitesse de croissance et conductance stomatique) ainsi que moléculaires ont été effectuées sur des plants de bouleau. Les modifications transcriptionnelles des aquaporines de protéines intrinsèques de la membrane plasmique (PIP) et ceux du tonoplaste (TIP) ont été évaluées dans les feuilles au cours d’un changement de l’humidité relative de l’air. Il s’agit de sept gènes de la sous famille des PIP (PIP1.1, PIP1.2, PIP1.3, PIP2.1, PIP2.4, PIP2.5 et PIP2.6) et quatre de la sous famille des TIP (TIP1.1, TIP1.2, TIP1.3 et TIP2.1). Les résultats des analyses écophysiologiques ont montré que l’augmentation de l’humidité relative n’a pas d’effet significatif sur la vitesse de croissance en hauteur et radiale mais sur la conductance stomatique des plants de bouleau. Les bouleaux ont une conductance stomatique plus élevée en condition de forte condition d’humidité relative (85%) qu’en condition normale d’humidité relative (65%).Au niveau moléculaire, huit des onze gènes étudiés (PIP1.1, PIP2.1, PIP2.5, PIP2.6, TIP1.1, TIP1.2, TIP1.3 et TIP2.1) ont une expression influencée significativement par l’augmentation de l’humidité relative. Tous les gènes étudiés à part le gène PIP1.3, sont sous exprimés en condition de forte humidité relative par rapport à la condition normale. Une analyse de corrélation a révélé l’existence d’une corrélation négative entre la conductance stomatique et l’expression de sept des gènes (PIP1.1, PIP2.1, PIP2.5, PIP2, TIP1.2, TIP1.3 et TIP2.1). On pourrait conclure qu’une sous expression de ces gènes permet une forte ouverture des stomates sous une forte humidité relative.
- Published
- 2021
7. Decline in canopy gas exchange with increasing tree height, atmospheric evaporative demand, and seasonal drought in co-occurring inland Pacific Northwest conifer species.
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Pangle, Robert, Kavanagh, Kathleen, and Duursma, Remko
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GAS exchange in plants , *PLANT canopies , *CONIFERS , *TREE height , *PLANT species - Abstract
Interspecific variation in stomatal conductance ( GS) and transpiration ( EL) has been documented in stands of co-occurring species, and this variation has been observed to differ with tree size and canopy height increase. In this study, we present data that examine fluctuations in canopy gas exchange across co-occurring species and varying canopy heights for three montane forest chronosequences located in an inland Pacific Northwest mixed-conifer forest. With the exception of Douglas-fir ( Pseudotsuga menziesii var. glauca (Beissn.) Franco), we observed consistent declines in canopy EL and GS with increasing height for the majority of species examined in our 2-year study. Along with declines in canopy GS, we observed decreases in leaf-specific hydraulic conductance ( KL) across species as canopy height increased. Seasonally, we observed declines in canopy GS during warmer and dryer summer months of both years. These decreases in GS were significant (up to 50%) and suggest that carbon assimilation in trees was limited during dryer months due to a combination of high evaporative demand and reduced soil H2O availability. Such reductions in GS during periods of increased plant water stress suggest that forest productivity in the inland Pacific Northwest may be impacted negatively if future climate predictions of increasing growing-season water stress are realized. [ABSTRACT FROM AUTHOR]
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- 2015
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8. L'effet des amendements cationiques sur la photosynthèse : le cas des érables à sucre (Acer Saccharum)
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Proulx, Alexandre and Proulx, Alexandre
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- 2020
9. Response of greenhouse-grown bell pepper (Capsicum annuum L.) to variable irrigation.
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Aladenola, Olanike and Madramootoo, Chandra
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BELL pepper ,WATER in agriculture ,AGRONOMY ,IRRIGATION water ,GREENHOUSE plants ,WATER efficiency - Abstract
Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2014
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10. Diversity of water use efficiency among Quercus robur genotypes: contribution of related leaf traits.
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Roussel, Magali, Le Thiec, Didier, Montpied, Pierre, Ningre, Nathalie, Guehl, Jean-Marc, and Brendel, Oliver
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ENGLISH oak ,ATMOSPHERIC water vapor ,GENOTYPE-environment interaction ,PHOTOSYNTHESIS ,ASSIMILATION (Sociology) - Abstract
Copyright of Annals of Forest Science (EDP Sciences) is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2009
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11. Déterminismes physiologiques, morphologiques et moléculaires de l’efficience d’utilisation de l’eau en lien avec la réponse à la sécheresse chez les peupliers : de la feuille à la plante entière
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Durand, Maxime, SILVA (SILVA), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL)-AgroParisTech, Université de Lorraine, Didier Le Thiec, Olivier Brendel, and ANR-11-LABX-0002,ARBRE,Recherches Avancées sur l'Arbre et les Ecosytèmes Forestiers(2011)
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Sécheresse ,Conductance stomatique ,Changement d’échelle ,Drought ,[SDE.IE]Environmental Sciences/Environmental Engineering ,Upscaling ,Changements climatiques ,Water use efficiency ,Climate change ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,Efficience d’utilisation de l’eau ,[SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology ,Stomatal conductance - Abstract
The number of drought events is expected to increase in intensity and frequency as a result of climate change. Since poplar productivity is closely linked to water availability, there is an increasing risk of decline in wood production from poplar plantations. Optimization of the ratio of biomass production to water used (i.e. water use efficiency, WUE) appears therefore as a relevant target for poplar research. Previous studies have shown the clonal diversity of WUE in poplar is driven mainly by stomatal conductance (gs). However gs and photosynthesis are not always tightly coupled which can result in large variations of WUE at leaf level. Additionally, because transpiration efficiency (TE) is laborious to measure, experiments are often conducted in pots in glasshouses. However in controlled conditions the environment is widely different than in the field and comparisons of WUE in controlled and field conditions are scarce in the literature. We assessed the diversity of stomatal dynamics among poplar genotypes under control or drought conditions grown in a glasshouse and in the field. We investigated the link between physiological, morphological and molecular factors and stomatal dynamics, and their influence on TE. Furthermore, we examined the relation between different estimators of WUE and its components between controlled and field conditions. Element content and candidate gene expression in the guard cells were also quantified at two times during the day to analyze their link to stomatal conductance. We found among the four genotypes studied significant genotypic variability of stomatal dynamics to irradiance and VPD which was altered by drought and growing conditions. Stomatal size and density as well as water use, but not WUE, were correlated to stomatal dynamics, emphasizing the importance and complexity of such mechanisms at the whole plant scale. Good agreements between leaf-level and whole-plant WUE among genotypes and between growing conditions were also found. Finally, distinct guard cell element contents and candidate gene expression, between leaf sides and time of day, linked with stomatal conductance draw attention to the diversity of components contributing to TE. These findings provides valuable information to better understand the diverse, sometimes unsuspected, leaf-level mechanisms driving water use efficiency at the whole plant scale.; Il est prévu une augmentation de l’intensité et de la fréquence des sécheresses dans les années à venir à cause des changements climatiques. Puisque la productivité des peupliers est étroitement liée à la disponibilité en eau, il existe un risque de déclin de la production de bois dans les peupleraies. L’optimisation de la biomasse produite en regard de l’eau consommée (efficience d’utilisation de l’eau, WUE) apparaît alors être une question de recherche prometteuse. Des études précédentes ont montré une diversité clonale de WUE chez les peupliers, pilotée principalement par la conductance stomatique (gs). Cependant, gs et l’assimilation en CO2 ne sont pas toujours connectés, ce qui peut conduire à de fortes variations de WUE au niveau foliaire. De plus, puisque la mesure de l’efficience d’utilisation de l’eau au niveau de la plante entière (TE) est laborieuse à mesurer, les expérimentations sont souvent réalisées en serre. Toutefois, les conditions contrôlées d’une serre conduisent à un environnement très différent des conditions naturelles, et les comparaisons de WUE entre conditions contrôlées et naturelles sont rares dans la littérature. Nous avons évalué la diversité des dynamiques stomatiques au sein de génotypes de peupliers sous conditions témoins et sous sécheresse en serre et en pépinière. Nous avons examiné le lien entre différents facteurs physiologiques, morphologiques et moléculaires et les dynamiques stomatiques, ainsi que leur influence sur TE. De plus, nous avons étudié la relation entre différents estimateurs de WUE et ses composantes entre des conditions contrôlées et naturelles. Le contenu en éléments minéraux et l’expression de gènes candidats ont également été quantifiés à deux moments de la journée pour analyser leur relation avec gs. Nous avons observé une variabilité génotypique significative des dynamiques stomatiques à la fois en réponse à l’irradiance et au VPD, de plus modifiée par la sécheresse et les conditions de croissance. La taille et la densité des stomates ainsi que la transpiration foliaire étaient fortement corrélées aux dynamiques stomatiques en serre, mais très peu en pépinière. Ces résultats soulignent l’importance et la complexité de ces mécanismes à l’échelle de la plante entière. WUE au niveau de la feuille et de la plante entière étaient relativement stables au sein des génotypes et entre conditions de croissance, mais bien moins avec la sécheresse. Enfin, des contenus en éléments et des expressions géniques distinctes ont été observées entre faces de la feuille et enter moments de la journée, en lien avec gs. Ces résultats fournissent de précieuses informations pour mieux comprendre les divers mécanismes foliaires pilotant WUE au niveau de la plante entière.
- Published
- 2019
12. On the minimum leaf conductance: its role in models of plant water use, and ecological and environmental controls
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Nicolas Martin-StPaul, Chris J. Blackman, Rosana López, Belinda E. Medlyn, Remko A. Duursma, Hervé Cochard, Hawkesbury Institute for the Environment, Western Sydney University, Laboratoire de Physique et Physiologie Intégratives de l’Arbre en environnement Fluctuant (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020]), Ecologie des Forêts Méditerranéennes (URFM), Institut National de la Recherche Agronomique (INRA), and Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut National de la Recherche Agronomique (INRA)
- Subjects
0106 biological sciences ,0301 basic medicine ,Stomatal conductance ,Physiology ,conductivité foliaire ,Acclimatization ,Drought tolerance ,drought tolerance ,Ecological and Environmental Phenomena ,plant water relations ,Plant Science ,Photosynthesis ,Models, Biological ,01 natural sciences ,écosystème ,03 medical and health sciences ,Ecosystem model ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,Ecosystem ,conductance stomatique ,cuticular conductance ,2. Zero hunger ,Vegetal Biology ,relation plante eau ,ecosystem modeling ,Ecology ,fungi ,Water ,Conductance ,tolérance à la sécheresse ,food and beverages ,stomatal conductance mode ,15. Life on land ,Plant Leaves ,030104 developmental biology ,Plant Stomata ,Soil water ,Environmental science ,Water use ,Biologie végétale ,010606 plant biology & botany - Abstract
Contents Summary 693 I. Introduction 693 II. Comparison of various definitions and measurement techniques of minimum conductance 694 III. Cuticular conductance 695 IV. Contribution of stomata 696 V. Environmental and ecological variation in minimum conductance 696 VI. Use of minimum conductance in models 698 VII. Conclusions 703 Acknowledgements 703 References 703 SUMMARY: When the rate of photosynthesis is greatly diminished, such as during severe drought, extreme temperature or low light, it seems advantageous for plants to close stomata and completely halt water loss. However, water loss continues through the cuticle and incompletely closed stomata, together constituting the leaf minimum conductance (gmin ). In this review, we critically evaluate the sources of variation in gmin , quantitatively compare various methods for its estimation, and illustrate the role of gmin in models of leaf gas exchange. A literature compilation of gmin as measured by the weight loss of detached leaves is presented, which shows much variation in this trait, which is not clearly related to species groups, climate of origin or leaf type. Much evidence points to the idea that gmin is highly responsive to the growing conditions of the plant, including soil water availability, temperature and air humidity - as we further demonstrate with two case studies. We pay special attention to the role of the minimum conductance in the Ball-Berry model of stomatal conductance, and caution against the usual regression-based method for its estimation. The synthesis presented here provides guidelines for the use of gmin in ecosystem models, and points to clear research gaps for this drought tolerance trait.
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- 2019
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13. Element content and expression of genes of interest in guard cells are connected to spatiotemporal variations in stomatal conductance
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Cyril Buré, Irène Hummel, Oliver Brendel, Nathalie Aubry, Ivana Tomášková, David Cohen, Didier Le Thiec, Maxime Durand, SILVA (SILVA), Institut National de la Recherche Agronomique (INRA)-AgroParisTech-Université de Lorraine (UL), University of Life Sciences Prague, FP7 Food, Agriculture and Fisheries, Biotechnology Watbio/311929, Institut National de la Recherche Agronomique (INRA), Region Grand-Est, French National Research Agency (ANR) ANR-12-LABXARBRE-01 European Union (EU), Le Thiec, Didier, Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL)-AgroParisTech, and Czech University of Life Sciences Prague (CZU)
- Subjects
0106 biological sciences ,0301 basic medicine ,Physiology ,[SDV]Life Sciences [q-bio] ,Plant Science ,01 natural sciences ,Trees ,chemistry.chemical_compound ,DROUGHT TOLERANCE ,HYBRID POPLAR ,Gene Expression Regulation, Plant ,Guard cell ,Arabidopsis thaliana ,Abscisic acid ,plant stomata ,Plant Proteins ,biology ,droughts ,populus euramericana ,food and beverages ,ABSCISIC-ACID ,ANION CHANNEL SLAC1 ,Proton-Translocating ATPases ,elements ,Populus ,RNA, Plant ,LIGHT-INTENSITY ,expression des gènes ,variabilité spatio temporelle ,Stomatal conductance ,DNA, Complementary ,Genotype ,Plant Development ,Aquaporin ,WATER TRANSPORT ,Black poplar ,03 medical and health sciences ,ADAXIAL STOMATA ,Botany ,black poplar ,conductance stomatique ,Water transport ,fungi ,HYDRAULIC CONDUCTIVITY ,Water ,Plant Transpiration ,PLASMA-MEMBRANE AQUAPORINS ,biology.organism_classification ,abaxial and adaxial surfaces ,gene expression ,stomatal conductance ,ARABIDOPSIS-THALIANA ,Plant Leaves ,Light intensity ,030104 developmental biology ,chemistry ,populus nigra ,Electron Probe Microanalysis ,010606 plant biology & botany - Abstract
Element content and expression of genes of interest on single cell types, such as stomata, provide valuable insights into their specific physiology, improving our understanding of leaf gas exchange regulation. We investigated how far differences in stomatal conductance (g(s)) can be ascribed to changes in guard cells functioning in amphistomateous leaves. g(s) was measured during the day on both leaf sides, on well-watered and drought-stressed trees (two Populus euramericana Moench and two Populus nigra L. genotypes). In parallel, guard cells were dissected for element content and gene expressions analyses. Both were strongly arranged according to genotype, and drought had the lowest impact overall. Normalizing the data by genotype highlighted a structure on the basis of leaf sides and time of day both for element content and gene expression. Guard cells magnesium, phosphorus, and chlorine were the most abundant on the abaxial side in the morning, where g(s) was at the highest. In contrast, genes encoding H+-ATPase and aquaporins were usually more abundant in the afternoon, whereas genes encoding Ca2+-vacuolar antiporters, K+ channels, and ABA-related genes were in general more abundant on the adaxial side. Our work highlights the unique physiology of each leaf side and their analogous rhythmicity through the day.
- Published
- 2019
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14. Altered stomatal dynamics of two Euramerican poplar genotypes submitted to successive ozone exposure and water deficit
- Author
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Joëlle Gérard, Yves Jolivet, Didier Le Thiec, Cyril Buré, Jean-Charles Olry, Nicolas Dusart, Marie-Noëlle Vaultier, SILVA (SILVA), Institut National de la Recherche Agronomique (INRA)-AgroParisTech-Université de Lorraine (UL), ANR-12-LABXARBRE-01, and Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL)-AgroParisTech
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[SDV.SA]Life Sciences [q-bio]/Agricultural sciences ,Stomatal conductance ,Genotype ,Vapor Pressure ,010504 meteorology & atmospheric sciences ,Light ,Vapour Pressure Deficit ,Health, Toxicology and Mutagenesis ,VPD ,Irradiance ,Context (language use) ,010501 environmental sciences ,Biology ,fonctionnement stomatique ,Toxicology ,01 natural sciences ,Water deficit ,water stress ,Combined treatment ,Ozone ,Species Specificity ,conductance stomatique ,Ozone exposure ,Stomata ,0105 earth and related environmental sciences ,tropospheric ozone ,Air Pollutants ,arbre ,Drought ,fungi ,populus deltoïdes x populus nigra ,comparaison de génotypes ,Water ,General Medicine ,Models, Theoretical ,Pollution ,Droughts ,Plant Leaves ,Horticulture ,Populus ,13. Climate action ,polluant atmosphérique ,Plant Stomata ,adaptation à la sécheresse ,Seasons ,stress hydrique - Abstract
The impact of ozone (O3) pollution events on the plant drought response needs special attention because spring O3 episodes are often followed by summer drought. By causing stomatal sluggishness, O3 could affect the stomatal dynamic during a subsequent drought event. In this context, we studied the impact of O3 exposure and water deficit (in the presence or in the absence of O3 episode) on the stomatal closure/opening mechanisms relative to irradiance or vapour pressure deficit (VPD) variation. Two genotypes of Populus nigra x deltoides were exposed to various treatments for 21 days. Saplings were exposed to 80 ppb/day O3 for 13 days, and then to moderate drought for 7 days. The curves of the stomatal response to irradiance and VPD changes were determined after 13 days of O3 exposure, and after 21 days in the case of subsequent water deficit, and then fitted using a sigmoidal model. The main responses under O3 exposure were stomatal closure and sluggishness, but the two genotypes showed contrasting responses. During stomatal closure induced by a change in irradiance, closure was slower for both genotypes. Nonetheless, the genotypes differed in stomatal opening under light. Carpaccio stomata opened more slowly than control stomata, whereas Robusta stomata tended to open faster. These effects could be of particular interest, as stomatal impairment was still present after O3 exposure and could result from imperfect recovery. Under water deficit alone, we observed slower stomatal closure in response to VPD and irradiance, but faster stomatal opening in response to irradiance, more marked in Carpaccio. Under the combined treatment, most of the parameters showed antagonistic responses. Our results highlight that it is important to take genotype-specific responses and interactive stress cross-talk into account to improve the prediction of stomatal conductance in response to various environmental modifications.
- Published
- 2019
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15. Carbon isotope composition, water use efficiency, and drought sensitivity are controlled by a common genomic segment in maize
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Zhenyu Yang, Adel Meziane, Sonja Blankenagel, Stella Eggels, Viktoriya Avramova, Thomas Presterl, Erwin Grill, Brigitte Poppenberger, Sebastian Gresset, Chris-Carolin Schön, Milena Ouzunova, Claude Welcker, François Tardieu, Eva Bauer, Wilfried Rozhon, Claudiu Niculaes, Technische Universität Munchen - Université Technique de Munich [Munich, Allemagne] (TUM), BBSRC John Innes Centre, Partenaires INRAE, Écophysiologie des Plantes sous Stress environnementaux (LEPSE), Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), KWS SAAT SE & Co.KGaA, Bavarian State Ministry of the Environment and Consumer Protection project network BayKlimaFit (Project TGC01GCUFuE69741) for providing the LI-6800 devices, German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) through the Sonderforschungsbereich 924 (SFB924): 'Molecular mechanisms regulating yield and yield stability in plants', project 'Maximizing photosynthetic efficiency in maize (FullThrottle)', funded by the Federal Ministry of Education and Research (BMBF, Germany) within the scope of the funding initiative 'Plant Breeding Research for the Bioeconomy' (Funding ID: 031B0205C), European Project: 284443,EC:FP7:INFRA,FP7-INFRASTRUCTURES-2011-1,EPPN(2012), John Innes Centre [Norwich], and Biotechnology and Biological Sciences Research Council (BBSRC)
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0106 biological sciences ,0301 basic medicine ,Stomatal conductance ,Quantitative Trait Loci ,Introgression ,carbone isotopique ,Biology ,01 natural sciences ,Chromosomes, Plant ,zea mays ,03 medical and health sciences ,chemistry.chemical_compound ,Stress, Physiological ,Genomic Segment ,Genetics ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,conductance stomatique ,lignée quasi isogénique ,Water-use efficiency ,Abscisic acid ,2. Zero hunger ,Carbon Isotopes ,Vegetal Biology ,croissance de la feuille ,Water ,General Medicine ,15. Life on land ,ddc ,Droughts ,Plant Leaves ,plateforme de phénotypage ,030104 developmental biology ,Water potential ,Phenotype ,chemistry ,Agronomy ,13. Climate action ,Soil water ,Plant Stomata ,région génomique ,Original Article ,efficience d'utilisation de l'eau ,adaptation au changement climatique ,Agronomy and Crop Science ,Water use ,Biologie végétale ,010606 plant biology & botany ,Biotechnology - Abstract
Key message A genomic segment on maize chromosome 7 influences carbon isotope composition, water use efficiency, and leaf growth sensitivity to drought, possibly by affecting stomatal properties. Abstract Climate change is expected to decrease water availability in many agricultural production areas around the globe. Therefore, plants with improved ability to grow under water deficit are urgently needed. We combined genetic, phenomic, and physiological approaches to understand the relationship between growth, stomatal conductance, water use efficiency, and carbon isotope composition in maize (Zea mays L.). Using near-isogenic lines derived from a maize introgression library, we analysed the effects of a genomic region previously identified as affecting carbon isotope composition. We show stability of trait expression over several years of field trials and demonstrate in the phenotyping platform Phenodyn that the same genomic region also influences the sensitivity of leaf growth to evaporative demand and soil water potential. Our results suggest that the studied genomic region affecting carbon isotope discrimination also harbours quantitative trait loci playing a role in maize drought sensitivity possibly via stomatal behaviour and development. We propose that the observed phenotypes collectively originate from altered stomatal conductance, presumably via abscisic acid. Electronic supplementary material The online version of this article (10.1007/s00122-018-3193-4) contains supplementary material, which is available to authorized users.
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- 2019
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16. Genetic control of stomatal conductance in maize and conditional effects to water deficit and evaporative demand as revealed by phenomics
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Alvarez Prado, Santiago, Cabrera Bosquet, Llorenç, Grau , Antonin, Coupel-Ledru, Aude, Millet, Emilie, Tardieu, Francois, Écophysiologie des Plantes sous Stress environnementaux (LEPSE), Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Écotron Européen de Montpellier, Centre National de la Recherche Scientifique (CNRS), Amélioration génétique et adaptation des plantes méditerranéennes et tropicales (UMR AGAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Biometris, Wageningen University and Research [Wageningen] (WUR), ANR‐10‐ BTBR‐01 (Amaizing), ANR-10-BTBR-0001,AMAIZING,Développer de nouvelles variétés de maïs pour une agriculture durable: une approche intégrée de la génomique à la sélection(2010), European Project: 244374,EC:FP7:KBBE,FP7-KBBE-2009-3,DROPS(2010), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)
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plateforme de phénotypage ,zea mays ,Vegetal Biology ,scénario climatique ,déficit hydrique ,qtl ,fungi ,food and beverages ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,conductance stomatique ,Biologie végétale ,contrôle génétique - Abstract
International audience; Plants tend to decrease transpiration under water deficit and/or high evaporative demand by closing stomata. 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 analyzed 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. They accounted for 58% of the additive genetic variance and 40% of the genotype × environment interaction. Light, vapour pressure deficit (VPD), or soil water potential largely accounted for the differences in allelic effects between experiments, thereby providing strong hypotheses for mechanisms of stomatal control and explaining part of the observed genotype × environment interaction. Light positively affected the allelic effects of three QTLs (e.g. R2 = 0.74), whereas VPD and water deficit negatively affected the allelic effects of other four QTLs. The combination of SNP effects, as affected by environmental conditions, accounted for the variability of stomatal conductance across a range of hybrids and environmental conditions (R2 = 0.86). This approach may therefore contribute prediction of stomatal control in diverse environments and to breeding for water efficient maize.
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- 2018
17. Drought tolerance: which mechanisms, traits and alleles for which drought scenarios?
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Tardieu, Francois, Millet, Emilie, Alvarez Prado, Santiago, Cabrera Bosquet, Llorenç, Lacube, Sébastien, Parent, Boris, Welcker, Claude, Écophysiologie des Plantes sous Stress environnementaux (LEPSE), Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), ANR, UE, and Inra
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plateforme de phénotypage ,Vegetal Biology ,mécanisme physiologique ,scénario climatique ,variabilité génétique ,fungi ,prédiction génétique ,tolérance à la sécheresse ,food and beverages ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,conductance stomatique ,Biologie végétale - Abstract
Plants are subjected every day to rapid variation of evaporative demand and soil water availability, resulting in rapid changes in stomatal conductance, expansive growth and metabolism over minutes. Because yield involves several months, the connection between physiological mechanisms and response of yield to drought scenarios faces a massive problem of time scales. Furthermore, yield results from optimization between traits and alleles that lead to either minimize the risk of crop failure or to increase crop production. Evolution has tended to favour conservative processes (short crop cycle, low transpiration and leaf area, large root systems) which are favourable under severe stresses, whereas yield in milder water deficits is associated with the opposite traits. Hence, one aims at identifying which traits and alleles are favourable in which drought scenarios, rather than at a generic ‘drought tolerance’. We deal with these methodological difficulties by combining phenomics, modelling, genetic analysis and genomic prediction. A first strategy explores the genetic variability of key processes, which are translated into parameters of a crop model. This requires detailed analyses in phenotyping platforms with a capacity of thousands of plants, with the relevant time scales. These parameters are analysed by GWAS and simulated via genomic prediction. The model can then simulate yield in hundreds of fields for hundreds of genotypes, from genetic parameters of each genotype and environmental conditions in each field. A second strategy directly explores the responses of yield to environmental conditions in contrasting environmental scenarios, e.g. in 40 fields. This results in a mixed model whose parameters are analysed genetically and can be estimated by genomic prediction, thereby allowing one to predict yields in new genotypes and fields. As a whole, the combination of field and platform data allows identification of combination
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- 2018
18. Structure is more important than physiology for estimating intracanopy distributions of leaf temperatures
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Sylvain Pincebourde, H. Arthur Woods, Marc Saudreau, University of Montana, Laboratoire de Physique et Physiologie Intégratives de l’Arbre en environnement Fluctuant (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020]), BIOlogie et GEstion des Risques en agriculture (BIOGER), AgroParisTech-Institut National de la Recherche Agronomique (INRA), Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut National de la Recherche Agronomique (INRA), Institut de recherche sur la biologie de l'insecte UMR7261 (IRBI), Université de Tours-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Physiologie Intégratives de l’Arbre en environnement Fluctuant - Clermont Auvergne (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Clermont Auvergne (UCA), and Institut National de la Recherche Agronomique (INRA)-AgroParisTech
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0106 biological sciences ,Canopy ,behavioral thermoregulation ,Jarvis parameters ,boundary layer ,Atmospheric sciences ,boundary layers ,01 natural sciences ,tree crown ,Mean radiant temperature ,sensitivity-analysis ,Original Research ,leaf inclination angle distribution ,changement climatique ,Vegetal Biology ,Ecology ,couche limite ,boundary-layer ,Vegetation ,climate change ,[SDE]Environmental Sciences ,feuille ,Stomatal conductance ,plant architecture ,climate ,insect ,leaf ,leaf area density ,leaf inclination ,angle distribution ,numerical model ,stomatal conductance ,temperature ,voxel ,canopy structure ,light interception ,model ,Environmental Sciences & Ecology ,Evolutionary Biology ,010603 evolutionary biology ,Forest ecology ,température ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,conductance stomatique ,Ecology, Evolution, Behavior and Systematics ,global change ,Nature and Landscape Conservation ,Tree canopy ,climat ,Plant community ,simulation numérique ,15. Life on land ,13. Climate action ,numerical simulation ,Environmental science ,Spatial variability ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,Biologie végétale ,010606 plant biology & botany - Abstract
International audience; Estimating leaf temperature distributions (LTDs) in canopies is crucial in forest ecology. Leaf temperature affects the exchange of heat, water, and gases, and it alters the performance of leaf-dwelling species such as arthropods, including pests and invaders. LTDs provide spatial variation that may allow arthropods to thermoregulate in the face of long-term changes in mean temperature or incidence of extreme temperatures. Yet, recording LTDs for entire canopies remains challenging. Here, we use an energy-exchange model (RATP) to examine the relative roles of climatic, structural , and physiological factors in influencing three-dimensional LTDs in tree canopies. A Morris sensitivity analysis of 13 parameters showed, not surprisingly, that climatic factors had the greatest overall effect on LTDs. In addition, however, structural parameters had greater effects on LTDs than did leaf physiological parameters. Our results suggest that it is possible to infer forest canopy LTDs from the LTDs measured or simulated just at the surface of the canopy cover over a reasonable range of parameter values. This conclusion suggests that remote sensing data can be used to estimate 3D patterns of temperature variation from 2D images of vegetation surface temperatures. Synthesis and applications. Estimating the effects of LTDs on natural plant-insect communities will require extending canopy models beyond their current focus on individual species or crops. These models, however, contain many parameters, and applying the models to new species or to mixed natural canopies depends on identifying the parameters that matter most. Our results suggest that canopy structural parameters are more important determinants of LTDs than are the physiological parameters that tend to receive the most empirical attention.
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- 2018
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19. Water budget and crop modelling for agrivoltaic systems: Application to irrigated lettuces
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Cyril Dejean, Bruno Cheviron, Jean-Marie Lopez, Yassin Elamri, Gilbert Belaud, Gestion de l'Eau, Acteurs, Usages (UMR G-EAU), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-AgroParisTech-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD)
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0106 biological sciences ,Conductance stomatique ,P06 - Sources d'énergie renouvelable ,F08 - Systèmes et modes de culture ,Agricultural engineering ,010501 environmental sciences ,01 natural sciences ,7. Clean energy ,Laitue ,F06 - Irrigation ,Water Science and Technology ,2. Zero hunger ,U10 - Informatique, mathématiques et statistiques ,Renewable energy ,Bilan hydrique ,[SDE]Environmental Sciences ,Irrigation ,Stomatal conductance ,Soil Science ,Climate change ,Crop ,water productivity [EN] ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Land use ,business.industry ,Modélisation des cultures ,Lactuca sativa ,OCCITANIE ,15. Life on land ,13. Climate action ,Agriculture ,Énergie renouvelable ,Environmental science ,Système de culture ,business ,Énergie solaire ,Agronomy and Crop Science ,Cropping ,010606 plant biology & botany ,Système photovoltaïque ,Utilisation de l'eau en agriculture - Abstract
International audience; The installation of tilting-angle solar panels above agricultural plots provides renewable energy and means of action to dampen some of the effects and hazards of climate change. When the panels are properly operated, their drop shadow reduces water consumption by the plants, as a consequence of alternating shade and sun bands with a short-term impact on the stomatal conductance and a global decrease of gas exchanges. This urged the development of a new model for crop growth and water budget, adapted here from existing literature to handle such transient conditions, characterized by short-term (infra-day) fluctuations. The main difficulty was to combine short-term fluctuations in the climatic forcings (radiation interception and rain redistribution by the panels) and long-term agronomic evaluation, hence the coexistence of several calculation time steps in model structure. All field experiments were conducted on purpose in the agrivoltaic plot of Lavalette (Montpellier, France). Specific adaptations consisted in describing the stomatal behavior of the plants for fluctuating solar radiations and varied water status, aiming at improving both the piloting of the solar panels and water management, i.e. the choice of irrigation amounts. Model simulations have been able to reproduce the expected benefits from agrivoltaic installations, for example showing that it is possible to improve land use efficiency and water productivity at once, by reducing irrigation amounts by 20%, when tolerating a decrease of 10% in yield or, alternatively, a slight extension of the cropping cycle. Agrivoltaism appears a solution for the future when facing climate change and the food and energy challenges, typically in the rural areas and the developing countries and especially if the procedure presented here proves relevant for other crops and contexts.
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- 2018
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20. Recurrent water deficit causes epigenetic and hormonal changes in citrus plants
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Neves, Diana Matos, Da Hora Almeida, Lucas Aragão, Santana-Vieira, Dayse Drielly Souza, Freschi, Luciano, Ferreira, Claudia Fortes, Soares Filho, Walter dos Santos, Costa, Marcio Gilberto Cardoso, Micheli, Fabienne, Coelho Filho, Mauricio Antonio, Da Silva Gesteira, Abelmon, Neves, Diana Matos, Da Hora Almeida, Lucas Aragão, Santana-Vieira, Dayse Drielly Souza, Freschi, Luciano, Ferreira, Claudia Fortes, Soares Filho, Walter dos Santos, Costa, Marcio Gilberto Cardoso, Micheli, Fabienne, Coelho Filho, Mauricio Antonio, and Da Silva Gesteira, Abelmon
- Abstract
The present study evaluated the physiological, molecular and hormonal parameters from scion/rootstock interaction of citrus plants during recurrent water deficit. Responses of the Valencia (VO) scion variety grafted on two rootstocks with different soil water extraction capacities, Rangpur Lime (RL) and Sunki Maravilha (SM), during three successive periods of water deficit: plants exposed to a single episode of water deficit (WD1) and plants exposed to two (WD2) and three (WD3) recurrent periods of WD were compared. The combinations VO/RL and VO/SM presented polymorphic alterations of epigenetic marks and hormonal (i.e. abscisic acid, auxins and salicylicacid) profiles, which were particularly prominent when VO/SM plantswere exposed toWD3 treatment. Upon successive drought events, the VO/SM combination presented acclimatization characteristics that enable higher tolerance to water deficit by increasing transpiration (E), stomatal conductance (g s ) and photosynthetic rate (A), which in turn may have facilitated the whole plant survival. Besides providing comprehensive data on the scion/rootstock interactions upon successive stress events, this study brings the first dataset suggesting that epigenetic alterations in citrus plants triggered by recurrent water deficit lead to improved drought tolerance in this crop species.
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- 2017
21. Leaf mortality and a dynamic hydraulic safety margin prevent significant stem embolism in the world's top wine regions during drought
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Delzon, Sylvain, Domec, Jean-Christophe, Zhang, Li, Delmas, Chloé, Van Leeuwen, Cornelis, Gambetta, Grégory, Laboratoire de Physique et Physiologie Intégratives de l’Arbre en environnement Fluctuant (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020]), Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Ecophysiologie et Génomique Fonctionnelle de la Vigne (UMR EGFV), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB)-Institut des Sciences de la Vigne et du Vin (ISVV)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Unité Mixte de Recherche en Santé Végétale (INRA/ENITA) (UMRSV), and Institut National de la Recherche Agronomique (INRA)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut des Sciences de la Vigne et du Vin (ISVV)
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xylème ,permeability coefficient ,conductivité hydraulique ,embolie ,Safety margins ,xylem ,embolism ,grapevine ,raisin ,stomatal conductance ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,conductance stomatique ,hydraulic conductivity ,xylem embolism ,grapes - Abstract
Grapevine is a crop of global economic importance that faces major challenges, notably through increased drought exposure. In order to maintain or even increase sustainability, it is critical to have a complete and accurate understanding of grapevine’s physiological behavior under drought. Nevertheless, studies report conflicting results regarding variety-specific behaviors. Examining multiple varieties, we utilized a combination of novel approaches to define water stress thresholds for a series of critical variables in maintaining vascular system integrity (water potential and stomatal regulation, stem embolism, leaf mortality, and recovery). We then compared the failure threshold under drought with a long-term field water status survey, across multiple varieties and climate conditions, in two of the world’s top wine regions, Napa and Bordeaux. We simultaneously assessed stomatal behavior in response to decreasing soil water availability and increasing evaporative demand, revealing a complex dynamic that defies the strict anisohydric/isohydric paradigm. Although inter-varietal differences were small, inter-organ and ontogenic differences were much greater, with the pressure inducing 50% loss of hydraulic conductivity Ψ50 decreasing along the growing season: from -2.1MPa in July to -3.2MPa in October. The unrecoverable water potential was observed at ~50% loss of hydraulic conductivity in the stem and ~80% leaf mortality. However, the minimum stem water potentials experienced in the field over the last decade have never passed Ψ50. This large safety margin is facilitated by hydraulic vulnerability segmentation promoting petiole embolism and leaf mortality. The water stress thresholds defined here provide a robust guide for informing viticultural management strategies under drought.
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- 2017
22. Recurrent water defcit causes epigenetic and hormonal changes in citrus plants
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Walter dos Santos Soares Filho, Marcio Gilberto Cardoso Costa, Luciano Freschi, Claudia Fortes Ferreira, Diana Matos Neves, Maurício Antônio Coelho Filho, Abelmon da Silva Gesteira, Fabienne Micheli, Lucas Aragão da Hora Almeida, and Dayse Drielly Souza Santana-Vieira
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0106 biological sciences ,0301 basic medicine ,Citrus ,Conductance stomatique ,F62 - Physiologie végétale - Croissance et développement ,Plant Roots ,01 natural sciences ,Antioxidants ,Epigenesis, Genetic ,Random Allocation ,chemistry.chemical_compound ,Plant Growth Regulators ,Gene Expression Regulation, Plant ,Photosynthesis ,Photosynthèse ,Génétique ,Abscisic acid ,Porte greffe ,Plant Proteins ,Transpiration ,chemistry.chemical_classification ,Multidisciplinary ,Dehydration ,food and beverages ,Antioxydant ,Droughts ,Physiologie végétale ,Medicine ,Activité enzymatique ,Rootstock ,Stomatal conductance ,Stress dû à la sécheresse ,Greffon ,F60 - Physiologie et biochimie végétale ,Science ,Drought tolerance ,Biology ,Acclimatization ,Article ,03 medical and health sciences ,Stress, Physiological ,Auxin ,Variété ,METILAÇÃO DE DNA ,Water ,Plant Transpiration ,DNA Methylation ,Hormone ,Plant Leaves ,030104 developmental biology ,Agronomy ,chemistry ,Plant Stomata ,H50 - Troubles divers des plantes ,010606 plant biology & botany - Abstract
The present study evaluated the physiological, molecular and hormonal parameters from scion/rootstock interaction of citrus plants during recurrent water deficit. Responses of the Valencia (VO) scion variety grafted on two rootstocks with different soil water extraction capacities, Rangpur Lime (RL) and Sunki Maravilha (SM), during three successive periods of water deficit: plants exposed to a single episode of water deficit (WD1) and plants exposed to two (WD2) and three (WD3) recurrent periods of WD were compared. The combinations VO/RL and VO/SM presented polymorphic alterations of epigenetic marks and hormonal (i.e. abscisic acid, auxins and salicylicacid) profiles, which were particularly prominent when VO/SM plantswere exposed toWD3 treatment. Upon successive drought events, the VO/SM combination presented acclimatization characteristics that enable higher tolerance to water deficit by increasing transpiration (E), stomatal conductance (g s ) and photosynthetic rate (A), which in turn may have facilitated the whole plant survival. Besides providing comprehensive data on the scion/rootstock interactions upon successive stress events, this study brings the first dataset suggesting that epigenetic alterations in citrus plants triggered by recurrent water deficit lead to improved drought tolerance in this crop species.
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- 2017
23. Predictable ‘meta-mechanisms’ emerge from feedbacks between transpiration and plant growth and cannot be simply deduced from short-term mechanisms
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Tardieu, Francois, Parent, Boris, Écophysiologie des Plantes sous Stress environnementaux (LEPSE), Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), European project FP7-KBBE-2012-6-311933 (Water4Crops), project ANR-10-BTBR-01 (Amaizing), ANR-10-BTBR-0001,AMAIZING,AMAIZING(2010), European Project: 244374, and ANR-10-BTBR-0001,AMAIZING,Développer de nouvelles variétés de maïs pour une agriculture durable: une approche intégrée de la génomique à la sélection(2010)
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plant architecture ,système racinaire ,Root system ,déficit hydrique ,acide abscisique ,fungi ,root systems ,food and beverages ,Hydraulics ,Growth ,dynamic model ,Feedback ,ABA ,Conductance ,Control ,abscissins ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,conductance stomatique ,écophysiologie végétale ,conductance hydraulique ,modèle dynamique ,water deficit ,architecture de la plante - Abstract
Growth under water deficit is controlled by short-term mechanisms but, because of numerous feedbacks, the combination of these mechanisms over time often results in outputs that cannot be deduced from the simple inspection of individual mechanisms. It can be analysed with dynamic models in which causal relationships between variables are considered at each time-step, allowing calculation of outputs that are routed back to inputs for the next time-step and that can change the system itself. We first review physiological mechanisms involved in seven feedbacks of transpiration on plant growth, involving changes in tissue hydraulic conductance, stomatal conductance, plant architecture and underlying factors such as hormones or aquaporins. The combination of these mechanisms over time can result in non-straightforward conclusions as shown by examples of simulation outputs: ‘over production of abscisic acid (ABA) can cause a lower concentration of ABA in the xylem sap ’, ‘decreasing root hydraulic conductance when evaporative demand is maximum can improve plant performance’ and ‘rapid root growth can decrease yield’. Systems of equations simulating feedbacks over numerous time-steps result in logical and reproducible emergent properties that can be viewed as ‘meta-mechanisms’ at plant level, which have similar roles as mechanisms at cell level.
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- 2017
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24. How do leaf and ecosystem measures of water-use efficiency compare?
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Lisa Wingate, Robert Clement, Nicolas Martin-StPaul, Maj-Lena Linderson, Jean-Marc Limousin, Belinda E. Medlyn, Peter Isaac, Yan-Shih Lin, Jürgen Knauer, Remko A. Duursma, Patrick Meir, Almut Arneth, Martin G. De Kauwe, Christopher B. Williams, Hawkesbury Institute for the Environment [Richmond] (HIE), Western Sydney University, Department of Biological Science, University of Denver, Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Department of Biogeochemical Integration [Jena], Max Planck Institute for Biogeochemistry (MPI-BGC), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Graduate School of Geography, Clark University, Institut für Meteorologie und Klimaforschung - Atmosphärische Umweltforschung (IMK-IFU), Karlsruher Institut für Technologie (KIT), School of Geosciences, Monash University [Clayton], OzFlux, University of Queensland [Brisbane], Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Université de Montpellier (UM), Centre National de la Recherche Scientifique (CNRS), Department of Physical Geography and Ecosystem Science [Lund], Lund University [Lund], Research School of Biology, Australian National University (ANU), Ecologie des Forêts Méditerranéennes (URFM), Institut National de la Recherche Agronomique (INRA), Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), ARC Discovery Grant DP120104055,Terrestrial Carbon Program (DE-FG02- 04ER63917 and DE-FG02-04ER63911), European Project: 609398,EC:FP7:PEOPLE,FP7-PEOPLE-2013-COFUND,AGREENSKILLSPLUS(2014), Western Sydney University (UWS), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UM3), Ecologie des Forêts Méditerranéennes [Avignon] (URFM 629), Interactions Sol Plante Atmosphère (ISPA), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), and Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)
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0106 biological sciences ,cycle du carbone ,Stomatal conductance ,010504 meteorology & atmospheric sciences ,Databases, Factual ,Physiology ,Eddy covariance ,stable isotopes ,Plant Science ,réserve en eau de la plante ,Forests ,Atmospheric sciences ,Poaceae ,01 natural sciences ,isotope stable ,Water balance ,Efficience d'utilisation de l'eau ,dynamique des écosystèmes ,carbon cycle ,eddy covariance ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,Ecosystem ,conductance stomatique ,water-use efficiency ,photosynthèse ,Water cycle ,Water-use efficiency ,bilan hydrique ,0105 earth and related environmental sciences ,Transpiration ,photosynthesis ,Ecology ,Water ,Plant Transpiration ,Vegetation ,15. Life on land ,leaf gas exchange ,Plant Leaves ,13. Climate action ,stomatal conductance ,covariance ,Environmental science ,plant functional type (PFT) ,utilisation de l'eau ,010606 plant biology & botany - Abstract
The terrestrial carbon and water cycles are intimately linked: the carbon cycle is driven by photosynthesis, while the water balance is dominated by transpiration, and both fluxes are controlled by plant stomatal conductance. The ratio between these fluxes, the plant water-use efficiency (WUE), is a useful indicator of vegetation function.WUE can be estimated using several techniques, including leaf gas exchange, stable isotope discrimination, and eddy covariance. Here we compare global compilations of data for each of these three techniques.We show that patterns of variation in WUE across plant functional types (PFTs) are not consistent among the three datasets. Key discrepancies include the following: leaf-scale data indicate differences between needleleaf and broadleaf forests, but ecosystem-scale data do not; leaf-scale data indicate differences between C3 and C4 species, whereas at ecosystem scale there is a difference between C3 and C4 crops but not grasslands; and isotope-based estimates of WUE are higher than estimates based on gas exchange for most PFTs.Our study quantifies the uncertainty associated with different methods of measuring WUE, indicates potential for bias when using WUE measures to parameterize or validate models, and indicates key research directions needed to reconcile alternative measures of WUE.
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- 2017
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25. Leaf mortality and a dynamic hydraulic safety margin prevent significant stem embolism in the world's top wine regions during drought
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Charrier, Guillaume, Delzon, Sylvain, Domec, Jean-Christophe, Zhang, Li, Delmas, Chloé, Van Leeuwen, Cornelis, Gambetta, Grégory, Ecophysiologie et Génomique Fonctionnelle de la Vigne (UMR EGFV), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB)-Institut des Sciences de la Vigne et du Vin (ISVV)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Biodiversité, Gènes & Communautés (BioGeCo), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB), Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Santé et agroécologie du vignoble (UMR SAVE), Biodiversité, Gènes et Communautés, Institut National de la Recherche Agronomique (INRA), Interactions Sol Plante Atmosphère (ISPA), Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro)-Institut National de la Recherche Agronomique (INRA), Ecophysiologie et Génomique Fonctionnelle de la Vigne (EGFV), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro)-Institut des Sciences de la Vigne et du Vin (ISVV)-Université de Bordeaux (UB), Unité Mixte de Recherche en Santé Végétale (INRA/ENITA) (UMR SAVE), Institut des Sciences de la Vigne et du Vin (ISVV)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut National de la Recherche Agronomique (INRA), Université de Bordeaux (UB)-Institut des Sciences de la Vigne et du Vin (ISVV)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Université de Bordeaux (UB)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut des Sciences de la Vigne et du Vin (ISVV)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro)-Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB), Unité Mixte de Recherche en Santé Végétale (INRA/ENITA) (UMRSV), Institut National de la Recherche Agronomique (INRA)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut des Sciences de la Vigne et du Vin (ISVV), and Admin, Oskar
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Xylème ,Vegetal Biology ,Conductance stomatique ,Safety Margins ,permeability coefficient ,Stomatal Conductance ,hydraulic conductivity ,stomatal conductance ,xylem embolism ,Safety margins ,grapevine ,Raisin ,xylem ,embolism ,Hydraulic Conductivity ,Embolie ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,[SDV.BV] Life Sciences [q-bio]/Vegetal Biology ,Grapevine ,Conductivité hydraulique ,Xylem Embolism ,Biologie végétale ,grapes - Abstract
International audience; Grapevine is a crop of global economic importance that faces major challenges, notably through increased drought exposure. In order to maintain or even increase sustainability, it is critical to have a complete and accurate understanding of grapevine’s physiological behavior under drought. Nevertheless, studies report conflicting results regarding variety-specific behaviors. Examining multiple varieties, we utilized a combination of novel approaches to define water stress thresholds for a series of critical variables in maintaining vascular system integrity (water potential and stomatal regulation, stem embolism, leaf mortality, and recovery). We then compared the failure threshold under drought with a long-term field water status survey, across multiple varieties and climate conditions, in two of the world’s top wine regions, Napa and Bordeaux. We simultaneously assessed stomatal behavior in response to decreasing soil water availability and increasing evaporative demand, revealing a complex dynamic that defies the strict anisohydric/isohydric paradigm. Although inter-varietal differences were small, inter-organ and ontogenic differences were much greater, with the pressure inducing 50% loss of hydraulic conductivity Ψ50 decreasing along the growing season: from -2.1MPa in July to -3.2MPa in October. The unrecoverable water potential was observed at ~50% loss of hydraulic conductivity in the stem and ~80% leaf mortality. However, the minimum stem water potentials experienced in the field over the last decade have never passed Ψ50. This large safety margin is facilitated by hydraulic vulnerability segmentation promoting petiole embolism and leaf mortality. The water stress thresholds defined here provide a robust guide for informing viticultural management strategies under drought.
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- 2017
26. Abscisic acid down-regulates hydraulic conductance of grapevine leaves in isohydric genotypes only
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Coupel-Ledru, Aude, Tyerman, Stephen, Masclef, Diane, Lebon, Eric, Christophe, Angélique, Edwards, Everard J, Simonneau, Thierry, Écophysiologie des Plantes sous Stress environnementaux (LEPSE), Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Plant Research Centre, University of Adelaide, Agriculture, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), programs LACCAVE, ANR-09-GENM-024-002, Australian Research Council Centre of Excellence in Plant Energy Biology, and ANR-09-GENM-0024,Vit-Sec,Interactions plantes / virus : identification des facteurs de l'hôte impliqués dans la réplication virale(2009)
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Isohydric / anisohydric ,Vegetal Biology ,organic chemicals ,acide abscisique ,fungi ,food and beverages ,Stomatal conductance ,ABA ,Leaf hydraulic conductance ,Transpiration ,Vitis vinifera L ,vitis vinifera ,transpiration des feuilles ,abscissins ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,conductance stomatique ,conductance hydraulique ,écophysiologie végétale ,Biologie végétale - Abstract
Plants evolved different strategies to cope with water stress. While isohydric species maintain their midday leaf water potential (ΨM) under soil water deficit by closing their stomata, anisohydric species maintain higher stomatal aperture and exhibit substantial reductions in ΨM. It was hypothesized that isohydry is related to a locally higher sensitivity of stomata to the drought-hormone abscisic acid (ABA). Interestingly, recent lines of evidence in Arabidopsis suggested that stomatal responsiveness is also controlled by an ABA action on leaf water supply upstream from stomata. Here, we tested the possibility in grapevine that different genotypes ranging from near isohydric to more anisohydric may have different sensitivities in these ABA responses. Measurements on whole plants in drought conditions were combined with assays on detached leaves fed with ABA. Two different methods consistently showed that leaf hydraulic conductance (Kleaf) was downregulated by exogenous ABA, with strong variations depending on the genotype. Importantly, variation between isohydry and anisohydry correlated with Kleaf sensitivity to ABA, with Kleaf in the most anisohydric genotypes being unresponsive to the hormone. We propose that observed response of Kleaf to ABA may be part of the overall ABA regulation of leaf water status.
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- 2017
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27. Modelling hydraulic functioning of an adult beech stand under non-limiting soil water and severe drought condition
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Marianne Peiffer, Andrée Tuzet, André Granier, Alain Perrier, Pauline Betsch, Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École des Ponts ParisTech (ENPC)-École polytechnique (X)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)
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0106 biological sciences ,Stomatal conductance ,010504 meteorology & atmospheric sciences ,Water flow ,fonctionnement hydraulique ,[SDV]Life Sciences [q-bio] ,potentiel hydrique foliaire ,forest stand ,fagus sylvatica ,modèle ,01 natural sciences ,Water balance ,bilan énergétique ,water balance ,dioxyde de carbone ,Evapotranspiration ,european beech ,conductance stomatique ,bilan hydrique ,0105 earth and related environmental sciences ,Transpiration ,carbonic anhydride ,Hydrology ,Tree canopy ,numerical models ,Ecology ,Ecological Modeling ,Water storage ,15. Life on land ,energy balance ,continuum sol plante atmosphère ,13. Climate action ,Soil water ,Environmental science ,peuplement forestier ,010606 plant biology & botany - Abstract
• SPAC model to predict forest water consumption under wet and dry conditions.• Interactions and feedbacks between physical climate and ecological processes.• Control of root water uptake by water diffusion processes between roots and soil.• Key processes involved: xylem hydraulic resistances and stomatal conductance.• Buffering action of capacitive discharge on daily fluctuations of xylem tension.Modelling hydraulic functioning of a forest stand is a prerequisite to predict the future impact of climate change on forests. In this paper, we used a process-based model of the soil-plant-atmosphere continuum to investigate the links between energy budget and water balance, and to emphasize the key processes involved in the control of transpiration and water status of forest trees. The model describes stomatal conductance as a function of photosynthesis, intercellular CO2 concentration and leaf water potential. The latter in turn depends on soil and tree storage water potentials, the water flux through the soil and the trees, hydraulic resistances and stomatal conductance. We have implemented in the model a detailed tree water storage scheme, canopy interception of precipitation, and the rate of change of forest canopy energy storage. In this model, physical climate processes and ecological processes are closely coupled which involves important interactions and feedbacks. The model reproduces the observed variation in leaf water potential in dry and wet conditions. It successfully captures the decrease in soil water content under both non-limiting soil water and severe drought conditions and there is a good agreement between measured and simulated sensible and latent heat fluxes throughout the season. Simulations also show that significant amounts of intercepted water can be lost through evaporation during rain events. The results corroborate that the concept of hydraulic capacitance provides a simple and effective means of simulating the buffering action of tree water storage on tree water status. The two key parameters that control transpiration and water status of the trees are xylem hydraulic resistances and sensitivity of stomata to leaf water potential. The results confirm that stomatal conductance cannot be modelled using leaf-level processes alone, but must be incorporated into a comprehensive model of water flow from soil through the plants to the atmosphere where various self-regulation are set up to ensure a complete water status equilibrium.
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- 2017
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28. Intra-crown spatial variability of leaf temperature and stomatal conductance enhanced by drought in apple trees as assessed by the RATP model
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Jérôme Ngao, M. Saudreau, Boris Adam, Laboratoire de Physique et Physiologie Intégratives de l’Arbre en environnement Fluctuant (PIAF), Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut National de la Recherche Agronomique (INRA), Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP), UE 1375 Phénotypage Au Champ des Céréales, Institut National de la Recherche Agronomique (INRA)-Santé des plantes et environnement (S.P.E.)-Biologie et Amélioration des Plantes (BAP)-Phénotypage Au Champ des Céréales (PHACC), and Institut National de la Recherche Agronomique (INRA)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])
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0106 biological sciences ,Atmospheric Science ,Stomatal conductance ,température de feuille ,010504 meteorology & atmospheric sciences ,Microclimate ,Apple tree ,teal temperature ,apple ,Atmospheric sciences ,01 natural sciences ,variabilité spatiale ,Botany ,intra-crown ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,conductance stomatique ,Water content ,0105 earth and related environmental sciences ,Global and Planetary Change ,Crown (botany) ,Forestry ,crab apples ,15. Life on land ,Temperature gradient ,pomme ,ratp ,13. Climate action ,stomatal conductance ,Soil water ,Environmental science ,Spatial variability ,spatial variability ,RATP model ,Agronomy and Crop Science ,010606 plant biology & botany - Abstract
The influence of drought intensity on spatial variability of leaf temperature was explored by the RATP model. We aimed at specifically determining (i) whether the spatial variability of leaf temperature was similar for the whole crown and for the top-viewed crown parts, and (ii) if the spatial variability at these two levels was comparable in a drought stress situation. During the pre-drought period, the temperature gradient along the leaf crown evolved diurnally under the major influence of incoming radiation for the whole crown, with the warmer leaves generally distributed in the top part of the crowns, leading to a significant spatial autocorrelation. In the upper part of the crown, the leaf temperature gradient was smaller than for the whole crown, and the leaf temperature values were more randomly distributed. As drought developed, the model reproduced realistic differences between leaf temperature and air temperature dynamics. Drought increased leaf spatial variability (in terms of stomatal conductance and temperature), regardless of the tree position considered. Moreover, for the whole crown, drought did not modify spatial autocorrelation with respect to the pre-drought period, whereas for the upper crown, the spatial autocorrelation felt under the significance level for the lowest relative soil water content levels (i.e., leaf temperatures were randomly distributed). When direct radiation reached low values, both the difference between leaf and air temperature and temperature gradient dramatically decreased compared to higher direct radiation levels, regardless of the air temperature and drought level. The geometrical and functional assumptions of the model are discussed. This study provided an example of the use of functional-structural plant models for assessing multiple interactions between climate, tree architecture and plant physiology, as well as the influence of drought on the within-crown microclimate.
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- 2017
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29. Rôle joué par le potassium dans la réponse au déficit hydrique du maïs (Zea mays L.) : des mécanismes physiologiques au fonctionnement intégré du peuplement
- Author
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Martineau, Elsa, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Université des Sciences et Technologies (Bordeaux 1), Jean-Christophe Domec, Lionel Jordan-Meille, and Jean-Paul Laclau
- Subjects
transport des sucres ,déficit hydrique ,potassium ,[SDV]Life Sciences [q-bio] ,[SDE]Environmental Sciences ,maïs (Zea mays L.) ,conductance stomatique ,rendement ,efficience d'utilisation de l'eau ,croissance - Abstract
Potassium (K) is a major nutrient known to help plants resist drought. In the context of climate change,quantifying the role of K on maize physiological acclimation to reduced precipitations is essential to betterpredict future productivity. Maize (Zea mays L.) plants grown under controlled or field conditions weresubmitted to different K and water levels. Plant growth (shoot and root biomass, grain yield) as well as plantwater status (transpiration, stomatal conductance, water potential) and ecophysiological mechanisms of Carbonmetabolism (photosynthesis, sugar transport) were studied. Regardless of the water regime and experimentalconditions, K nutrition increased growth and whole-plant development and improved grain yield. The effect ofwater stress on stomatal regulation was not straightforward and depended on the level of K fertilization. Theeffects of water or K deficit tend to decrease photosynthesis. Drought or K nutrition affected more leafphotosynthesis in old than in young leaves, and sugar transport did not seem to be a growth limiting factor. Ourresults demonstrated a strong effect of K on biomass production and a higher water use efficiency with less of animpact on leaf-level physiology. This better water use was mainly the consequence of the positive effect of leafarea on yield, and not due to a reduce water use.; Le potassium (K) est un élément majeur connu pour contribuer à la résistance des plantes à la sècheresse. L'étudede son influence sur la réponse physiologique du maïs (Zea mays L.) sous contrainte hydrique est essentiellepour prédire la future productivité dans un contexte de changements climatiques, en particulier de la diminutiondes précipitations. Des modalités d'apports en K et en eau ont été croisées et soumises à des plants de maïs,élevés en condition contrôlées ou cultivés au champ. La croissance (biomasses aériennes et racinaires,rendements en grain) ainsi que les mécanismes écophysiologiques du métabolisme carboné (photosynthèse,transport des sucres) et du statut hydrique (transpiration, conductance stomatique, potentiels hydriques) ont étéétudiés. L'apport de K a contribué à l'augmentation de la croissance, le développement et le rendement grain quelque soit le régime hydrique imposé au maïs et les conditions d'expérimentation. Les résultats attendus sur lameilleure régulation stomatique en cas de déficit hydrique sont moins évidents. L'effet du stress hydrique ou dela déficience en K tendent à diminuer la photosynthèse. Cependant, ces effets ressortent plus sur les feuillesâgées que sur les feuilles jeunes. Dans ces mêmes conditions, le transport des sucres ne semble pas être unélément limitant de la croissance. Plusieurs résultats convergent pour attribuer au K un rôle dans la maîtrise despertes en eau (par unité de surface foliaire) et sur la meilleure efficience d'utilisation de l'eau. Néanmoins, cetteefficience est imputée à des meilleurs rendements, liés à une surface foliaire plus importante, et non pas à unemoindre consommation de l'eau.
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- 2016
30. Quantifying the role of potassium in maize (Zea mays L.) resistance to water stress : from leaf-level physiological mechanisms to whole-plant functioning
- Author
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Martineau, Elsa, Interactions Sol Plante Atmosphère (ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), ISPA Interaction Sol Plante Atmosphère UMR 1391, Université de Bordeaux, Jean-Christophe Domec, Lionel Jordan-Meille, Jean-Paul Laclau, STAR, ABES, Interactions Sol Plante Atmosphère (UMR ISPA), and Université des Sciences et Technologies (Bordeaux 1)
- Subjects
Yield ,Conductance stomatique ,[SDV]Life Sciences [q-bio] ,[SDE.MCG]Environmental Sciences/Global Changes ,Growth ,Stomatal conductance ,Efficience d'utilisation de l'eau ,[SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems ,[SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry ,[SDU.STU.GC] Sciences of the Universe [physics]/Earth Sciences/Geochemistry ,[SDV.EE.ECO] Life Sciences [q-bio]/Ecology, environment/Ecosystems ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,[SDV.BV] Life Sciences [q-bio]/Vegetal Biology ,Maize (Zea mays L.) ,Croissance ,Maïs (Zea mays L.) ,Drought ,Water use efficiency ,[SDE.MCG] Environmental Sciences/Global Changes ,[SDE]Environmental Sciences ,Sugar transport ,Potassium ,Déficit hydrique ,potassium ,déficit hydrique ,maïs (Zea mays L.) ,croissance ,conductance stomatique ,transport des sucres ,rendement ,efficience d'utilisation de l'eau ,Rendement ,Transport des sucres - Abstract
Le potassium (K) est un élément majeur connu pour contribuer à la résistance des plantes à la sècheresse. L'étudede son influence sur la réponse physiologique du maïs (Zea mays L.) sous contrainte hydrique est essentiellepour prédire la future productivité dans un contexte de changements climatiques, en particulier de la diminutiondes précipitations. Des modalités d'apports en K et en eau ont été croisées et soumises à des plants de maïs,élevés en condition contrôlées ou cultivés au champ. La croissance (biomasses aériennes et racinaires,rendements en grain) ainsi que les mécanismes écophysiologiques du métabolisme carboné (photosynthèse,transport des sucres) et du statut hydrique (transpiration, conductance stomatique, potentiels hydriques) ont étéétudiés. L'apport de K a contribué à l'augmentation de la croissance, le développement et le rendement grain quelque soit le régime hydrique imposé au maïs et les conditions d'expérimentation. Les résultats attendus sur lameilleure régulation stomatique en cas de déficit hydrique sont moins évidents. L'effet du stress hydrique ou dela déficience en K tendent à diminuer la photosynthèse. Cependant, ces effets ressortent plus sur les feuillesâgées que sur les feuilles jeunes. Dans ces mêmes conditions, le transport des sucres ne semble pas être unélément limitant de la croissance. Plusieurs résultats convergent pour attribuer au K un rôle dans la maîtrise despertes en eau (par unité de surface foliaire) et sur la meilleure efficience d'utilisation de l'eau. Néanmoins, cetteefficience est imputée à des meilleurs rendements, liés à une surface foliaire plus importante, et non pas à unemoindre consommation de l'eau., Potassium (K) is a major nutrient known to help plants resist drought. In the context of climate change,quantifying the role of K on maize physiological acclimation to reduced precipitations is essential to betterpredict future productivity. Maize (Zea mays L.) plants grown under controlled or field conditions weresubmitted to different K and water levels. Plant growth (shoot and root biomass, grain yield) as well as plantwater status (transpiration, stomatal conductance, water potential) and ecophysiological mechanisms of Carbonmetabolism (photosynthesis, sugar transport) were studied. Regardless of the water regime and experimentalconditions, K nutrition increased growth and whole-plant development and improved grain yield. The effect ofwater stress on stomatal regulation was not straightforward and depended on the level of K fertilization. Theeffects of water or K deficit tend to decrease photosynthesis. Drought or K nutrition affected more leafphotosynthesis in old than in young leaves, and sugar transport did not seem to be a growth limiting factor. Ourresults demonstrated a strong effect of K on biomass production and a higher water use efficiency with less of animpact on leaf-level physiology. This better water use was mainly the consequence of the positive effect of leafarea on yield, and not due to a reduce water use.
- Published
- 2016
31. Analyse de la variabilité génotypique et modélisation de l’architecture et du fonctionnement photosynthétique et stomatique d’un sous échantillon de la core-collection française de pommiers (Malus domestica X Borkh)
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Thomasset, Rémi, Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP), and France. Ecole d'Ingénieurs en Agriculture (ESITPA), FRA.
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Farquhar ,architecture ,Jarvis ,[SDV]Life Sciences [q-bio] ,[SDE]Environmental Sciences ,pommier ,conductance stomatique ,Photosynthèse - Abstract
Master; Ce présent rapport a été réalisé au sein de l’UMR AGAP et PIAF de l’INRA. Il a été analysé et modélisé l’architecture et le fonctionnement photosynthétique et stomatique d’un sous échantillon d’une core-collection française de pommiers. En tout il était analysé 6 génotypes choisis au préalable grâce à leurs différences de vigueurs rencontrées lors de l’expérience Phénoarch en 2014. Les pommiers étaient plantés dans un verger à Mauguio (34). Afin de réaliser la modélisation architecturale, un relevé a été effectué grâce à la digitalisation manuelle. Les données montraient des différences significatives en terme architectural. Afin d’implémenter les modèles de fonctionnement foliaire des courbes de réponses de la photosynthèse et de la conductance stomatique à différents facteurs environnementaux ont été réalisés en 2015 et 2016. Bien qu’il n’y ait pas de différences significatives, des tendances ont été montrées. La modélisation des maquettes d’arbres et de la photosynthèse étaient satisfaisantes bien que la conductance stomatique n’était pas convenablement simulée, en raison de variabilité de fonctionnement stomatique entre feuilles. Par la suite il sera important de re-calibrer le modèle de conductance stomatique et de réaliser des simulations compilant l’architecture et le fonctionnement foliaire.
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- 2016
32. Modelling water use efficiency in a dynamic environment: An example using Arabidopsis thaliana
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Tracy Lawson, Howard Griffiths, Yizhou Wang, Michael R. Blatt, Jack S A Matthews, Simon Rogers, Adrian Hills, Oliver Brendel, Silvere Vialet-Chabrand, University of Essex, Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), University of Glasgow, University of Cambridge [UK] (CAM), BBSRC (BB/1001187_1, BB/L001276/1, BB/L019205/1), Griffiths, Howard [0000-0002-3009-6563], and Apollo - University of Cambridge Repository
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0106 biological sciences ,0301 basic medicine ,Conservation of Natural Resources ,Stomatal conductance ,water use efficiency ,Arabidopsis ,Plant Science ,Biology ,Photosynthesis ,modèle ,01 natural sciences ,activité diurne ,Article ,03 medical and health sciences ,Botany ,Genetics ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,conductance stomatique ,photosynthèse ,Water-use efficiency ,Transpiration ,Stomatal density ,numerical models ,Diurnal ,photosynthesis ,Plant Stomata ,arabidopsis thaliana ,Water ,Bayes Theorem ,Plant Transpiration ,General Medicine ,Intrinsic water use efficiency ,dynamics ,Carbon Dioxide ,Models, Theoretical ,15. Life on land ,Photosynthetic capacity ,Circadian Rhythm ,Light intensity ,030104 developmental biology ,dynamique ,efficience d'utilisation de l'eau ,Biological system ,Agronomy and Crop Science ,010606 plant biology & botany - Abstract
Highlights • A model scaling stoma behaviour at leaf level is proposed. • The model is tested by reproducing natural variations of light intensity. • Stomatal aperture and photosynthesis decrease as a function of sugar accumulation. • Leaf anatomy influences the rapidity of stomatal conductance. • The model dissects intrinsic water use efficiency into traits of interest., Intrinsic water use efficiency (Wi), the ratio of net CO2 assimilation (A) over stomatal conductance to water vapour (gs), is a complex trait used to assess plant performance. Improving Wi could lead in theory to higher productivity or reduced water usage by the plant, but the physiological traits for improvement and their combined effects on Wi have not been clearly identified. Under fluctuating light intensity, the temporal response of gs is an order of magnitude slower than A, which results in rapid variations in Wi. Compared to traditional approaches, our new model scales stoma behaviour at the leaf level to predict gs and A during a diurnal period, reproducing natural fluctuations of light intensity, in order to dissect Wi into traits of interest. The results confirmed the importance of stomatal density and photosynthetic capacity on Wi but also revealed the importance of incomplete stomatal closure under dark conditions as well as stomatal sensitivity to light intensity. The observed continuous decrease of A and gs over the diurnal period was successfully described by negative feedback of the accumulation of photosynthetic products. Investigation into the impact of leaf anatomy on temporal responses of A, gs and Wi revealed that a high density of stomata produces the most rapid response of gs but may result in lower Wi.
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- 2016
- Full Text
- View/download PDF
33. Contribution du métabolisme de l'ABA et de la conductivité hydraulique à la réponse de la transpiration en situation de contrainte hydrique chez la Vigne : variabilité génétique et effets du greffage
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Rossdeutsch, Landry, Ecophysiologie et Génomique Fonctionnelle de la Vigne (UMR EGFV), Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB)-Institut des Sciences de la Vigne et du Vin (ISVV)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Université de Bordeaux, Nathalie Ollat, Ecophysiologie et Génomique Fonctionnelle de la Vigne (EGFV), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro)-Institut des Sciences de la Vigne et du Vin (ISVV)-Université de Bordeaux (UB), Institut des Sciences de la Vigne et du Vin [Villenave d'Ornon] (ISVV), and Université de Bordeaux (UB)
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[SDV.SA]Life Sciences [q-bio]/Agricultural sciences ,Hydraulic conductance ,[SDV]Life Sciences [q-bio] ,variabilité génétique ,Stomatal conductance ,ABA-metabolites ,porte-greffe ,ABA ,conductance hydraulique ,conductance stomatique ,déficit hydrique ,expression de gènes ,PIP aquaporines ,signalisation ,vigne ,vitis vinifera ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,Genes expression ,Water deficit ,matériel végétal ,[SDE]Environmental Sciences ,Grapevine ,Genetic variability ,Rootstock ,adaptation au changement climatique ,PIP aquaporins - Abstract
Dans le contexte de changement climatique, la compréhension des mécanismes régissant les pertes en eau de la vigne peut permettre d'adapter le matériel végétal pour maintenir la productivité de la vigne et la qualité du vin. L'adaptation à la sécheresse est un caractère complexe faisant intervenir des mécanismes physiologiques liés aux génotypes du greffon et du porte-greffe. Mais les effets du porte-greffe sur la régulation stomatique du greffon sont mal connus. La production par les racines de signaux chimiques tels que l'ABA et/ou hydraulique pourraient y contribuer. La réponse physiologique et moléculaire à la contrainte hydrique a été analysée sur de jeunes boutures pour 7 porte-greffes plus ou moins adaptés à la sécheresse et 2 cépages connus pour leur caractère iso ou anisohydrique. Puis 23 combinaisons greffon/porte-greffe issues de ces génotypes ont été étudiées. Une analyse métabolique sur l'accumulation de l'ABA et ses dérivés a été menée sur feuilles, racines et dans la sève xylémienne. Ces informations ont été couplées à des analyses transcriptomiques sur des gènes du métabolisme et de la signalisation de ABA, et codant des aquaporines de type PIP. L‘analyse conjointe des données physiologiques, métabolomiques et transcriptomiques ont permis d'identifier des composants moléculaires discriminant les porte-greffes selon leur fond génétique et leur adaptation à la sécheresse. Les réponses globales à la contrainte hydrique sont mieux coordonnées au sein d‘un même tissu qu‘entre racines et feuilles. A l‘échelle de la plante greffée, une prépondérance du signal hydraulique est probable. Certains gènes répondent spécifiquement aux interactions greffon/porte-greffe., In the context of climate change, understanding the mechanisms governing the water loss of the vine is necessary to adapt the plant material to maintain the productivity of the vine and wine quality. The adaptation to drought is a complex trait involving physiological mechanisms related to scion and rootstock genotypes. But the effects of the rootstock on stomatal regulation graft are still unknown. Production by roots of chemical signals such as ABA and / or hydraulic ones be involved. Molecular and physiological responses to water stress were analyzed on young cuttings for 7 rootstocks more or less adapted to drought and 2 varieties known for their iso or anisohydric behaviour. Then 23 combinations scion / rootstock from these genotypes were investigated. Metabolic analyses for ABA and its derivatives was conducted in leaves, roots and in the xylem sap. The information was integrated with transcriptomic analyzes for genes involved in ABA metabolism and signaling, and encoding PIP aquaporins. Joint analyses of physiological data, metabolomic and transcriptomic allow the identification of the molecular components discriminating rootstocks according to their genetic background and their adaptation to drought. Global responses to water stress are better coordinated within the same tissue between roots and leaves. At the scale of the grafted plant, a preponderance of the hydraulic signal is likely. Some genes specifically respond to the scion / rootstock interactions.
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- 2015
34. Régulation du climat thermique urbain par les arbres : ombrage et température du couvert
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Marc Saudreau, Kastendeuch, Jérome Ngao, Georges Najjar, Thierry Ameglio, Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP), and Université de Strasbourg (UNISTRA)
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Vegetal Biology ,température de feuille ,Conductance stomatique ,Evapotranspiration ,Ville ,Température Feuille ,[SDV]Life Sciences [q-bio] ,conductance stomatique ,evapotranspiration ,température Feuille ,ville ,city ,leaf temperature ,stomatal conductance ,évapotranspiration ,[SDE]Environmental Sciences ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,Biologie végétale - Abstract
La structuration spatiale, la capacité d’intercepter la lumière et de transpirer des feuilles confèrent aux arbres un potentiel d’action sur le climat urbain notamment thermique. Les travaux d’expérimentation et de modélisation entrepris depuis une vingtaine d’années ont permis de quantifier ce potentiel à différentes échelles : de la rue à la ville en passant par le quartier. Plus particulièrement les arbres agissent sur le climat urbain en modifiant le bilan radiatif (effet d’ombrage du sol et des bâtiments) et diminution de la température d’air via la transpiration. La compréhension de ce mécanisme permet de mieux formaliser les interactions entre une strate arborée (arbre seul ou parc) et le climat urbain, et d’identifier les conditions nécessaires qui permettront d’assurer une régulation thermique. Parmi ces conditions l’accès à l’eau apparaît comme primordial., Trees can potentially have a positive effect on the thermal urban climate due to their 3D spatial structure, their ability to intercept light and to evaporate water. Experimental and modelling works done since twenty years enabled to verify and quantify this potential at different scales: from the street to the city through the neighborhood. More particularly it has been shown that trees impact the urban climate system by altering the urban radiation balance by shading soil and buildings, and by lowering air temperature through transpiration process. Understanding these mechanisms makes it possible to better formalize interactions between a tree cover (single tree or park) and urban climate, and to identify conditions that will ensure a thermal regulation. Among these conditions water availability appears to be crucial.
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- 2015
- Full Text
- View/download PDF
35. Variabilité génétique de la tolérance à la sécheresse d'arbres d'intérêts agronomiques : rôle de la vulnérabilité à la cavitation du xylème
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Jinagool, Wanploy, Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP), Université Blaise Pascal - Clermont-Ferrand II, Stéphane Herbette, Poonpipope Kasemsap, and STAR, ABES
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Juglans spp ,[SDV.SA]Life Sciences [q-bio]/Agricultural sciences ,[SDV.SA] Life Sciences [q-bio]/Agricultural sciences ,Conductance stomatique ,Drought ,Water stress ,Vulnerability to cavitation ,Vulnérabilité à la cavitation ,Stress hydrique ,Stomatal conductance ,Hydraulic ,Hydraulique ,Sécheresse ,Hevea brasiliensis ,Malus domestica - Abstract
In a context of climatic changes, drought stress and water management are regarded as one of the most important constraints for agricultural sector. Thus the selection for drought tolerance became a main objective for many breeding programs. Vulnerability to cavitation is considered a trait of interest for the selection for extreme drought stress, especially for woody species. However, the extent of its variability and its relation to drought tolerance are poorly documented on intraspecific level, particularly for cultivated species. In this study the genetic variability of vulnerability to cavitation was studied on three different experimental devices with three trees of agronomic interest that are threatened by the risk of drought: walnut, rubber and apple trees. Low or no variation in xylem vulnerability to cavitation was found in the studied species and between two species of walnuts despite differences previously reported features. These results suggested a canalization of cavitation resistance on critical organs (branches and stems). In apple tree, the rootstock was suspected to cause the narrow resistance to cavitation on the scion. On the contrary, differences on other traits in response to drought stress such as stomatal regulation, leaf shedding or vulnerability to cavitation on petiole were found. Therefore, vulnerability to cavitation of critical organs was not a relevant parameter for the selection of drought tolerance and breeding programs on the species studied did not appear to affect this parameter., Dans un contexte de changements climatiques, le stress hydrique et la gestion de l'eau sont considérés comme une contrainte importante pour le secteur agricole. Ainsi la sélection pour la tolérance à la sécheresse est devenue un objectif majeur pour de nombreux programmes de sélection. La vulnérabilité à la cavitation est considérée comme un trait d'intérêt pour la sélection à une sécheresse extrême, en particulier pour les plantes ligneuses. Pourtant, l'étendue de sa variabilité et sa relation avec la tolérance à la sécheresse sont mal documentées à l’échelle intra-spécifique, et en particulier dans les espèces cultivées. Dans cette étude, la variabilité génétique de la vulnérabilité à la cavitation a été étudiée sur trois dispositifs expérimentaux différents avec trois arbres d’intérêt agronomique qui sont menacés par le risque de sécheresse: noyer, hévéa et pommier. Une faible ou aucune, variation de la vulnérabilité à la cavitation a été trouvée dans les espèces étudiées ainsi qu'entre deux espèces de noyers malgré les différences de traits précédemment rapportés. Ces résultats suggèrent une canalisation de la résistance à la cavitation dans les organes critiques (branches, tiges). Chez le pommier, le porte-greffe est soupçonné de provoquer de la plus étroite résistance à la cavitation sur le greffon. Par contre, des différences ont bien étés trouvées sur d’autres traits de réponse à la sécheresse comme la régulation stomatique, la chute des feuilles ou encore la vulnérabilité à la cavitation dans le pétiole. Ainsi, la vulnérabilité à la cavitation des organes critiques n’est pas un paramètre pertinent pour la sélection de la tolérance à la sécheresse, et les programmes de sélection sur les espèces étudiées ne semblent pas avoir affecté ce paramètre.
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- 2015
36. Unveiling stomata 24/7: can we use carbonyl sulfide (COS) and oxygen isotopes (18O) to constrain estimates of nocturnal transpiration across didfferent evolutionary plant forms?
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Gimeno Chocarro, Teresa, Ogée, Jérôme, Bosc, Alexandre, Genty, Bernard, Wohl, Steven, Wingate, Lisa, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Biologie végétale et microbiologie environnementale - UMR7265 (BVME), Institut de Biosciences et Biotechnologies d'Aix-Marseille (ex-IBEB) (BIAM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), European Geosciences Union (EGU). DEU., Direction de Recherche Fondamentale (CEA) (DRF (CEA)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)
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sulfure de carbonyle ,[SDE.MCG]Environmental Sciences/Global Changes ,conductance stomatique ,eau dans la plante ,Milieux et Changements globaux ,anhydrase carbonique ,échange gazeux ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
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- 2015
37. Clonal variability for vulnerability to cavitation and other drought-related traits in Hevea brasiliensis Müll. Arg
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Wanploy Jinagool, Ratchanee Rattanawong, Krissada Sangsing, Tete Severien Barigah, Frédéric Gay, Hervé Cochard, Poonpipope Kasemsap, stephane herbette, Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier (PIAF), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de la Recherche Agronomique (INRA), Office of Agricultural Research and Development Region 7, Surat Thani Rubber Research Center, Department of agriculture, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Department of Horticulture, Tropical Agriculture, Kasertsart University, Institut National de la Recherche Agronomique (INRA)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Nong Khai Rubber Research Center, Rubber Research Institute, Surat Thani Rubber Research Center, Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), Hevea Research Platform, DORAS Centre, and Kasersart University
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Conductance stomatique ,conduction stomatique ,Stress dû à la sécheresse ,leaf shedding ,hydraulics ,Sélection ,Phénotype ,drought ,xylem ,embolism ,Relation plante eau ,F30 - Génétique et amélioration des plantes ,Cavitation ,clonal variability ,Hevea brasiliensis ,stomatal conductance ,Variation génétique ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,sécheresse ,clone ,Expérimentation ,Xylème ,Vegetal Biology ,Précipitation ,fungi ,food and beverages ,Physiologie végétale ,F60 - Physiologie et biochimie végétales ,Résistance à la sécheresse ,embolisme ,H50 - Troubles divers des plantes ,Biologie végétale - Abstract
International audience; Selection for drought-tolerant clones has become a major challenge in rubber breeding programs undertaken to ensure the sustainability of natural rubber production, as rubber plantations are expanding in drought-prone areas. Xylem vulnerability to cavitation is a trait related to drought-induced mortality. It can be rapidly evaluated without subjecting plant materials to drought stress, making it useful in large-scale screening for drought tolerance in the near future. We first compared the most widely used techniques for measuring vulnerability to cavitation (air pressurization and Cavitron) on this species, and the effect of sample conditions (size, age and sunlight exposure), in order to ensure reliable analysis. Secondly, ten rubber clones were compared for their xylem vulnerability to cavitation in branches and petioles, and for other traits related to drought response, including stomatal response and leaf shedding occurring during a simulated drought. We also tested the plasticity of vulnerability to cavitation on two clones grown in three locations with contrasting precipitation regimes. We found no clonal variability and a small phenotypic plasticity for xylem vulnerability to cavitation in branches. However, clonal differences in xylem vulnerability to cavitation were found in petioles, and clones also showed differences in stomatal response and in leaf shedding behavior in response to a simulated drought. Our study suggests a genetic canalization for vulnerability to cavitation in organs critical for survival, such as branches, whereas there are clonal differences for traits related to drought avoidance: vulnerability to cavitation of petioles, leaf shedding behavior and stomatal response. The insights gained in this study for screening rubber tree clones for drought tolerance is also discussed.
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- 2015
38. Régulation du climat thermique urbain par les arbres : ombrage et température du couvert
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Saudreau, M., Kastendeuch, P., NGAO, Jérome, Najjar, G., Ameglio, Thierry, Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP), and Université de Strasbourg (UNISTRA)
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température Feuille ,city ,stomatal conductance ,[SDV]Life Sciences [q-bio] ,[SDE]Environmental Sciences ,evapotranspiration ,ville ,conductance stomatique ,leaf temperature - Abstract
Ce numéro d’Innovations Agronomiques rassemble les présentations du colloque « Ville à haute intensité écologique : la place du végétal » qui s'est tenu à Angers le 30 septembre 2015.; National audience; Trees can potentially have a positive effect on the thermal urban climate due to their 3D spatial structure, their ability to intercept light and to evaporate water. Experimental and modelling works done since twenty years enabled to verify and quantify this potential at different scales: from the street to the city through the neighborhood. More particularly it has been shown that trees impact the urban climate system by altering the urban radiation balance by shading soil and buildings, and by lowering air temperature through transpiration process. Understanding these mechanisms makes it possible to better formalize interactions between a tree cover (single tree or park) and urban climate, and to identify conditions that will ensure a thermal regulation. Among these conditions water availability appears to be crucial.; La structuration spatiale, la capacité d’intercepter la lumière et de transpirer des feuilles confèrent aux arbres un potentiel d’action sur le climat urbain notamment thermique. Les travaux d’expérimentation et de modélisation entrepris depuis une vingtaine d’années ont permis de quantifier ce potentiel à différentes échelles : de la rue à la ville en passant par le quartier. Plus particulièrement les arbres agissent sur le climat urbain en modifiant le bilan radiatif (effet d’ombrage du sol et des bâtiments) et diminution de la température d’air via la transpiration. La compréhension de ce mécanisme permet de mieux formaliser les interactions entre une strate arborée (arbre seul ou parc) et le climat urbain, et d’identifier les conditions nécessaires qui permettront d’assurer une régulation thermique. Parmi ces conditions l’accès à l’eau apparaît comme primordial.
- Published
- 2015
- Full Text
- View/download PDF
39. Modelling the climatic drivers determining photosynthesis and carbon allocation in evergreen Mediterranean forests using multiproxy long time series
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Guillaume Simioni, Richard Joffre, Jean-Marc Ourcival, Frédéric Guibal, Guillermo Gea-Izquierdo, Joel Guiot, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UM3), Ecologie des Forêts Méditerranéennes [Avignon] (URFM 629), Institut National de la Recherche Agronomique (INRA), ANR-11-LABX-0010/11-LABX-0010,LabEx DRIIHM,Dispositif de recherche interdisciplinaire sur les Interactions Hommes-Milieux(2011), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), Ecologie des Forêts Méditerranéennes (URFM), G. Gea-Izquierdo was funded by the Labex OT-Med (no. ANR-11-LABEX-0061) from the 'Investissements d'Avenir' program of the French National Research Agency through the A*MIDEX project (no. ANR-11-IDEX-0001-02). Federation de Recherche FR3098 ECCOREV, the labex IRDHEI and OHM-BMP also supported the study., ANR-11-LABX-0010,DRIIHM / IRDHEI,Dispositif de recherche interdisciplinaire sur les Interactions Hommes-Milieux(2011), Gea-Izquierdo, Guillermo, Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)
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Canopy ,0106 biological sciences ,010504 meteorology & atmospheric sciences ,Biodiversité et Ecologie ,lcsh:Life ,Atmospheric sciences ,01 natural sciences ,CRITICAL-APPRAISAL ,QUERCUS-ILEX ,ATMOSPHERIC CO2 CONCENTRATIONS ,FAGUS-SYLVATICA ,quercus ilex ,pinus halepensis ,sud de la france ,TREE-GROWTH ,dynamique du carbone ,Ecology ,[SDE.IE]Environmental Sciences/Environmental Engineering ,Provence mining area ,lcsh:QE1-996.5 ,forêt méditerranéenne ,facteur climatique ,SEVERE DROUGHT ,[SDE]Environmental Sciences ,WATER-USE EFFICIENCY ,Stomatal conductance ,[SDE.MCG]Environmental Sciences/Global Changes ,Eddy covariance ,Climate change ,Biodiversity and Ecology ,lcsh:QH540-549.5 ,LabEx DRIIHM ,Ecosystem ,conductance stomatique ,photosynthèse ,Leaf area index ,SCOTS PINE ,Ecology, Evolution, Behavior and Systematics ,Earth-Surface Processes ,modélisation ,0105 earth and related environmental sciences ,Forest inventory ,OHM Bassin Minier de Provence ,Evergreen ,quercus coccifera ,15. Life on land ,lcsh:Geology ,lcsh:QH501-531 ,OAK WOODLANDS ,Observatoires Hommes-Millieux ,13. Climate action ,Environmental science ,ECOSYSTEM ,lcsh:Ecology ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,010606 plant biology & botany - Abstract
Climatic drivers limit several important physiological processes involved in ecosystem carbon dynamics including gross primary productivity (GPP) and carbon allocation in vegetation. Climatic variability limits these two processes differently. We developed an existing mechanistic model to analyse photosynthesis and variability in carbon allocation in two evergreen species at two Mediterranean forests. The model was calibrated using a combination of eddy covariance CO2 flux data, dendrochronological time series of secondary growth and forest inventory data. The model was modified to be climate explicit in the key processes addressing the acclimation of photosynthesis and the pattern of C allocation, particularly to water stress. It succeeded in fitting both the high- and the low-frequency response of stand GPP and carbon allocation to stem growth. This would support its capability to address both C-source and C-sink limitations. Simulations suggest a decrease in mean stomatal conductance in response to a recent enhancement in water stress and an increase in mean annual intrinsic water use efficiency (iWUE) in both species during the last 50 years. However, this was not translated into a parallel increase in ecosystem water use efficiency (WUE). The interannual variability in WUE closely followed that in iWUE at both sites. Nevertheless, long-term decadal variability in WUE followed the long-term decrease in annual GPP matching the local trend in annual precipitation observed since the late 1970s at one site. In contrast, at the site where long-term precipitation remained stable, GPP and WUE did not show a negative trend and the trees buffered the climatic variability. In our simulations these temporal changes were related to acclimation processes at the canopy level, including modifications in LAI and stomatal conductance, but also partly related to increasing [CO2] because the model includes biochemical equations where photosynthesis is directly linked to [CO2]. Long-term trends in GPP did not match those in growth, in agreement with the C-sink hypothesis. The model has great potential for use with abundant dendrochronological data and analyse forest performance under climate change. This would help to understand how different interfering environmental factors produce instability in the pattern of carbon allocation and, hence, the climatic signal expressed in tree rings.
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- 2015
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40. Variabilité génétique de la tolérance à la sécheresse d'arbres d'intérêts agronomiques: rôle de la vulnérabilité à la cavitation du xylème
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JINAGOOL, WANGLOY, ProdInra, Migration, Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP), Université Blaise Pascal (Clermont Ferrand 2), and Stéphane Herbette
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Juglans spp ,Hevea brasiliensis ,Malus domestica ,hydraulique ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,Stress hydrique ,conductance stomatique ,[SDV.BV] Life Sciences [q-bio]/Vegetal Biology ,vulnérabilité à la cavitation ,sécheresse - Abstract
Dans un contexte de changements climatiques, le stress hydrique et la gestion de l'eau sont considérées comme une contrainte importante pour le secteur agricole. Ainsi la sélection pour la tolérance à la sécheresse est devenue un objectif majeur pour de nombreux programmes de sélection. La vulnérabilité à la cavitation est considérée comme un trait d'intérêt pour la sélection à une sécheresse extrême, en particulier pour les plantes ligneuses. Pourtant, l'étendue de sa variabilité et sa relation avec la tolérance à la sécheresse sont mal documentées à l’échelle intra-spécifique, et en particulier dans les espèces cultivées. Dans cette étude, la variabilité génétique de la vulnérabilité à la cavitation a été étudiée sur trois dispositifs expérimentaux différents avec trois arbres d’intérêt agronomique qui sont menacés par le risque de sécheresse: noyer, hévéa et pommier. Une faible ou aucune, variation de la vulnérabilité à la cavitation a été trouvée dans les espèces étudiées ainsi qu'entre deux espèces de noyers malgré les différences de traits précédemment rapportés. Ces résultats suggèrent une canalisation de la résistance à la cavitation dans les organes critiques (branches, tiges). Chez le pommier, le porte-greffe est soupçonné de provoquer de la plus étroite résistance à la cavitation sur le greffon. Par contre, des différences ont bien étés trouvées sur d’autres traits de réponse à la sécheresse comme la régulation stomatique, la chute des feuilles ou encore la vulnérabilité à la cavitation dans le pétiole. Ainsi, la vulnérabilité à la cavitation des organes critiques n’est pas un paramètre pertinent pour la sélection de la tolérance à la sécheresse, et les programmes de sélection sur les espèces étudiées ne semblent pas avoir affecté ce paramètre.
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- 2015
41. Characterization of the adaptive response of grapevine (cv. Tempranillo) to UV-B radiation under water deficit conditions
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Fermín Morales, Manuel Sánchez-Díaz, Inmaculada Pascual, Serge Delrot, Eric Gomès, Jone Aguirreolea, Johann Martínez-Lüscher, Ecophysiologie et Génomique Fonctionnelle de la Vigne (UMR EGFV), Université de Bordeaux (UB)-Institut des Sciences de la Vigne et du Vin (ISVV)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Fundación Universitaria de Navarra, Nafarroako Gobernua, Conseil régional d'Aquitaine, Ministerio de Ciencia e Innovación (España), European Commission, Asociación de Amigos de la Universidad de Navarra, European Cooperation in Science and Technology, Gobierno de Aragón, and Ecophysiologie et Génomique Fonctionnelle de la Vigne (EGFV)
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Chlorophyll ,Stomatal conductance ,Vitis vinifera L ,Photosystem II ,Ultraviolet Rays ,Tempranillo ,Deficit irrigation ,Water Deficit ,Déficit Hydrique ,Plant Science ,Biology ,Photosynthesis ,UV-B radiation ,Méthanol ,Respiration ,Genetics ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,Vitis ,UV-B absorbing compounds ,Desiccation ,Photosynthèse ,Uv-B Absorbing Compounds ,Water deficit ,chemistry.chemical_classification ,Uv-B Radiation ,Superoxide Dismutase ,Variabilité Phénologique ,Water ,Ripening ,Rayonnement Ultraviolet ,General Medicine ,3. Good health ,chemistry ,Agronomy ,Vitis Vinifera ,Phenology ,Conductance Stomatique ,Baie de raisin ,Xanthophyll ,Plant Stomata ,Photorespiration ,Spectroradiométrie ,Lipid Peroxidation ,Agronomy and Crop Science - Abstract
34 Pags.- 3 Tabls.- 6 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/01689452, This work aims to characterize the physiological response of grapevine (Vitis vinifera L.) cv. Tempranillo to UV-B radiation under water deficit conditions. Grapevine fruit-bearing cuttings were exposed to three levels of supplemental biologically effective UV-B radiation (0, 5.98 and 9.66 kJ m−2 day−1) and two water regimes (well watered and water deficit), in a factorial design, from fruit-set to maturity under glasshouse-controlled conditions. UV-B induced a transient decrease in net photosynthesis (Anet), actual and maximum potential efficiency of photosystem II, particularly on well watered plants. Methanol extractable UV-B absorbing compounds (MEUVAC) concentration and superoxide dismutase activity increased with UV-B. Water deficit effected decrease in Anet and stomatal conductance, and did not change non-photochemical quenching and the de-epoxidation state of xanthophylls, dark respiration and photorespiration being alternative ways to dissipate the excess of energy. Little interactive effects between UV-B and drought were detected on photosynthesis performance, where the impact of UV-B was overshadowed by the effects of water deficit. Grape berry ripening was strongly delayed when UV-B and water deficit were applied in combination. In summary, deficit irrigation did not modify the adaptive response of grapevine to UV-B, through the accumulation of MEUVAC. However, combined treatments caused additive effects on berry ripening., This work was supported by Fundación Universitaria de Navarra, Navarra-Aquitaine Cooperation Program (Gobierno de Navarra and Conseil Régional d’Aquitaine), Ministerio de Ciencia e Innovación of Spain (MCINN BFU2011-26989), European Union (FP7-KBBE-2012-6-singlestage), Asociación de Amigos de la Universidad de Navarra (grant to J. M-L), UV4growth COST Action FA0906 and Gobierno de Aragón (A03 research group).
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- 2015
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42. Clonal variability for vulnerability to cavitation and other drought-related traits in Hevea brasiliensis Müll. Arg.
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Jinagool, Wanploy, Rattanawong, Ratchanee, Sangsing, Krissada, Barigah, Têté Sévérien, Gay, Frédéric, Cochard, Hervé, Kasemsap, Poonpipope, Herbette, Stéphane, Jinagool, Wanploy, Rattanawong, Ratchanee, Sangsing, Krissada, Barigah, Têté Sévérien, Gay, Frédéric, Cochard, Hervé, Kasemsap, Poonpipope, and Herbette, Stéphane
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Selection for drought-tolerant clones has become a major challenge in rubber breeding programs undertaken to ensure the sustainability of natural rubber production, as rubber plantations are expanding in drought-prone areas. Xylem vulnerability to cavitation is a trait related to drought-induced mortality. It can be rapidly evaluated without subjecting plant materials to drought stress, making it useful in large-scale screening for drought tolerance in the near future. We first compared the most widely used techniques for measuring vulnerability to cavitation (air pressurization and Cavitron) on this species, and the effect of sample conditions (size, age and sunlight exposure), in order to ensure reliable analysis. Secondly, ten rubber clones were compared for their xylem vulnerability to cavitation in branches and petioles, and for other traits related to drought response, including stomatal response and leaf shedding occurring during a simulated drought. We also tested the plasticity of vulnerability to cavitation on two clones grown in three locations with contrasting precipitation regimes. We found no clonal variability and a small phenotypic plasticity for xylem vulnerability to cavitation in branches. However, clonal differences in xylem vulnerability to cavitation were found in petioles, and clones also showed differences in stomatal response and in leaf shedding behavior in response to a simulated drought. Our study suggests a genetic canalization for vulnerability to cavitation in organs critical for survival, such as branches, whereas there are clonal differences for traits related to drought avoidance: vulnerability to cavitation of petioles, leaf shedding behavior and stomatal response. The insights gained in this study for screening rubber tree clones for drought tolerance is also discussed.
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- 2015
43. Les besoins en eau des plantes et l'introduction de la génétique
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Durand, Jean-Louis, Unité de Recherche Pluridisciplinaire Prairies et Plantes Fourragères (P3F), and Institut National de la Recherche Agronomique (INRA)
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[SDV.SA]Life Sciences [q-bio]/Agricultural sciences ,réserve utile ,surface foliaire ,racines ,potentiel hydrique ,transpiration ,conductance stomatique ,Agricultural sciences ,résistance à la sécheresse ,plante cultivée ,diversité génétique ,besoin en eau ,Sciences agricoles - Abstract
La sécheresse s’impose comme l’une de limitations de la production agricole les plus difficiles à combattre. Chez les espèces qui s’y exposent, le recours à l’irrigation reste, quand elle est possible, la méthode la plus efficace. Cependant, un travail constant en amélioration des plantes depuis près d’un siècle a permis des gains non négligeables en jouant sur plusieurs caractères de la plante concourant à l’élaboration du rendement. La recherche progresse sur tous les fronts en coordonnant l’exploitation raisonnée et systématique de l’ensemble des ressources génétiques avec l’analyse toujours plus fine de la physiologie des variations génétiques de la résistance à la sécheresse.
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- 2014
44. Disturbances in European beech water relation during an extreme drought
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Marianne Peiffer, Vincent Badeau, André Granier, Nathalie Bréda, Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), and Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL)
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Canopy ,Stomatal conductance ,réserve en eau du sol ,[SDV]Life Sciences [q-bio] ,variabilité verticale ,fagus sylvatica ,Atmospheric sciences ,Temperate deciduous forest ,Twig ,couronne ,Fagus sylvatica ,Botany ,conductance stomatique ,arbre forestier feuillu ,Leaf water potential ,Soil water deficit ,Crown position ,Seasonal pattern ,Beech ,sécheresse ,Transpiration ,Vegetal Biology ,Ecology ,biology ,Forestry ,15. Life on land ,biology.organism_classification ,transpiration des feuilles ,Soil water ,relation hydrique ,Environmental science ,stress hydrique ,Biologie végétale - Abstract
International audience; Context In the context of a probable increase in intensity and frequency of extreme summer drought events, a better understanding of the key processes involved in water relations is needed to improve the theoretical foundations of predictive process-based models. Aims This paper aims to analyse how temperate deciduous trees cope with water shortage. Methods The exceptional summer drought of 2003 in Europe provided an opportunity to monitor stomatal conductance and twig water potential in European beech (Fagus sylvatica L.) at predawn and midday and to analyse variations with respect to leaf height within the canopy. By comparing our field measurements of twig water potential to values found in the literature, we confirmed the strong impact of soil water shortage on crown water relations. Results This paper shows that (1) the vertical gradient of stomatal conductance within the crown disappeared under extreme soil water depletion; (2) at maximum drought inten-sity, predawn twig water potential (ψ pd) reached −2.3 MPa at a height of 14 m in the crown and −2.0 MPa at a height of 10 m. The significant differences in ψ pd between the two measure-ment heights in the canopy may be due to night transpiration; (3) there was a close relationship between predawn twig water potential and relative extractable soil water; (4) as drought conditions intensified, there was a close relationship between canopy radiation interception and predawn water potential, as estimated daily from relative extractable soil water.
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- 2014
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45. Comment mesurer la contrainte hydrique de la vigne, de la plante au vignoble
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Saurin, Nicolas, Tisseyre, Bruno, Lebon, Eric, Institut National de la Recherche Agronomique (INRA), Information – Technologies – Analyse Environnementale – Procédés Agricoles (UMR ITAP), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)
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EXTRAPOLATION SPATIALE ,DEFICIT HYDRIQUE ,POTENTIEL HYDRIQUE ,Δ13C ,CONDUCTANCE STOMATIQUE ,[SDE]Environmental Sciences ,FLUX DE SEVE ,IMAGERIE INFRAROUGE THERMIQUE ,PSYCHROMETRIE IN SITU ,INDICATEUR DE CROISSANCE - Abstract
National audience; L’irrigation de précision est essentielle dans les zones arides et semi-arides confrontées à des réserves en eau limitées. Cela a poussé la communauté scientifique à développer de nouvelles technologies pour le pilotage de l'irrigation permettant de rationaliser les apports en fonction des besoins de la culture vis-à-vis des objectifs de production. Parmi celles-ci, les indicateurs de stress hydrique mesurés directement sur la plante ont démontré le plus grand potentiel. Ainsi, les mesures de potentiel hydrique foliaire, de température du couvert, de flux de sève, ou de variation de diamètre de tronc, entre autres variables, se sont révélés utiles non seulement pour des fins de recherche, mais aussi de façon applicatives dans les vignobles commerciaux. Couplées à des modèles d’extrapolation spatiale basés sur des données auxiliaires à moyenne ou haute résolution (δ13C, NDVI) ces méthodes peuvent permettre de piloter l’irrigation tout en prenant en compte l‘hétérogénéité spatiale de l’état hydrique du vignoble.
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- 2014
46. Coping with low light under high atmospheric dryness: shade acclimation in a Mediterranean conifer (Abies pinsapo Boiss.)
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José Javier Peguero-Pina, Stéphane Herbette, Domingo Sancho-Knapik, Jaume Flexas, Eustaquio Gil-Pelegrín, Ülo Niinemets, Hervé Cochard, Unidad de Recursos Forestales, Centro de Investigación y Tecnología Agroalimentaria (CITA) de Aragón, Research Group on Plant Biology under Mediterranean Conditions, Universitat de les Illes Balears (UIB), Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier (PIAF), Institut National de la Recherche Agronomique (INRA)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP), Centro de Investigacion y Technologia Agroalimentaria de Aragon (CITA), Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, and Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA)
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0106 biological sciences ,Mediterranean climate ,Canopy ,Light ,Physiology ,Vapour Pressure Deficit ,Acclimatization ,Plant Science ,01 natural sciences ,Trees ,carbon allocation ,forest understory ,leaf-specific conductivity ,stomatal conductance ,vapor pressure deficit ,Sotobosque ,Photosynthesis ,sécheresse ,allocation de carbone ,Vegetal Biology ,biology ,facteur abiotique ,Mediterranean Region ,arbre forestier résineux ,Understory ,Darkness ,Droughts ,ombre ,Abies ,Stomatal conductance ,Aclimatación ,Environment ,010603 evolutionary biology ,Stress, Physiological ,abies pinsapo ,climat méditerranéen ,Abies pinsapo ,Botany ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,conductance stomatique ,Water transport ,déficit de pression de vapeur ,végétation du sous bois ,Water ,Biological Transport ,conductivité hydraulique ,15. Life on land ,biology.organism_classification ,Plant Leaves ,Agronomy ,Plant Stomata ,adaptation à la lumière ,Environmental science ,Biologie végétale ,010606 plant biology & botany - Abstract
Plant species living in the understory increase carbon (C) allocation toward leaf production for maximizing light capture at the expense of roots and stems, with negative consequences for the whole-plant hydraulic conductance. Moreover, under some conditions, the high atmospheric evaporative demand occurring in Mediterranean areas may be not well buffered by the canopy, which might be the case for relict conifer Abies pinsapo Boiss. growing in the forest understory. We hypothesized that acclimation to combined understory shade and high atmospheric dryness can be achieved through the adjustment of water losses to cope with the restriction in water transport. The results reveal high structural plasticity in A. pinsapo that allows light harvesting of this species to maximize light capture in the forest understory, and maintain a positive C balance under low light conditions. However, growth in the understory resulted in reduced leaf-specific conductivity, up to approximately four to five times, implying decreased plant capacity to supply water to the leaves. In order to cope with the high atmospheric evaporative demand in the understory, there is an adjustment of the stomatal conductance to the hydraulic conductivity by means of a reduction in the stomatal density in understory individuals, which is due to the almost complete lack of stomata in the adaxial side of the needles. To the extent of our knowledge, such a drastic phenotypic response found in a conifer when growing under shaded conditions had not been previously reported. Published
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- 2014
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47. Modelling daily variations of stomatal conductance: contributions of a dynamic approach and impact on the intrinsic water use efficiency in oak
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Vialet-Chabrand, Silvère, Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Université de Lorraine, Erwin Dreyer, Oliver Brendel, and UL, Thèses
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[SDV.SA]Life Sciences [q-bio]/Agricultural sciences ,Conductance stomatique ,Chêne ,Modélisation inversée ,Stomatal conductance ,Réponse temporelle ,Chênes-Métabolisme ,[SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry ,Biomasse végétale ,Inverse modelling ,Oaks ,Plantes -- Écophysiologie ,Temporal response ,[SDV.SA.SF] Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry - Abstract
Intrinsic water use efficiency (Wi), defined as the ratio between net CO2 assimilation rate (A) and stomatal conductance to water vapour (gs), is a leaf level estimator of the trade-off between biomass accumulation and water loss at the plant level. A number of studies have shown a strong inter and intra-specific diversity, usually using a time integrated estimator of this trait. However, the origin of this diversity is not yet well known. Up to now, research on the daily variations of Wi have shown a stronger influence of gs on the diversity of Wi as compared to A. An inverse modelling approach has allowed partitioning the variations of gs observed during daily time-courses into parameters, which describe the stomatal responses to different microclimatic variables. Compared to steady-state gs models, the development of a new dynamic model of gs has allowed adding a necessary temporal dimension, which describes the temporal response of stomata to environmental variations. The observed diversity of these temporal stomatal responses was not related to stomatal density or size. The temporal responses of stomata were shown to be asymmetric between opening and closing, which impacts the observed diversity of gs during daily time courses as well as whole plant water relations. Overall these results suggest two components that determine the variations of Wi related to gs during daily time courses: one component due to the temporal response of stomata in itself, and one component which is due to differences in the sensing of microclimate variations, L'efficience intrinsèque d'utilisation de l'eau (Wi) définit comme le rapport de l'assimilation nette de CO2 (A) sur la conductance stomatique à la vapeur d'eau (gs) est un estimateur au niveau foliaire du compromis fait par la plante entre l'accumulation de biomasse et sa consommation en eau. De nombreuses études ont révélé une forte diversité inter et intra-spécifique de ce trait intégré dans le temps dont l'origine est encore mal connue. Les travaux réalisés sur les variations journalières de A et gs ont jusqu'à maintenant révélé un rôle plus important de la diversité de gs dans la diversité de Wi. Une approche de modélisation inversée a permis de décomposer les variations de gs, observées lors de cinétiques journalières, sous la forme de paramètres décrivant les réponses stomatiques aux différentes variables microclimatiques. Comparé aux modèles décrivant les variations de gs en régime permanent, le développement d'un nouveau modèle dynamique a permis d'ajouter une dimension temporelle essentielle décrivant la réponse temporelle des stomates aux variations microclimatiques. La diversité des réponses temporelles des stomates détectée ne semble pas dépendre de leur densité ou de leur taille. Elle présente toutefois une asymétrie entre l'ouverture et la fermeture des stomates qui participe à la diversité des variations journalières de gs et impacte le bilan hydrique journalier au niveau du plant entier. Ainsi, on peut distinguer deux composantes aux variations journalières de Wi liées à gs : une composante temporelle due à la lente réponse des stomates et une autre composante due aux différences de perception des variations du microclimat
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- 2013
48. Rôle de la régulation stomatique et de la capacité de détoxication foliaire dans l'estimation d'un seuil de risque à l'ozone pour la végétation
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Dumont, Jennifer, Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Université de Lorraine, and Didier Le Thiec
- Subjects
[SDV.SA]Life Sciences [q-bio]/Agricultural sciences ,Ozone ,Conductance stomatique ,Stomates ,Plantes -- Effets de l'ozone ,Peupliers ,Détoxication ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,Stomatal conductance ,Peuplier ,Detoxification ,Poplar - Abstract
Tropospheric ozone is a major air pollutant that acts as a phytotoxin. It enters the leaf through the stomata before being dissolved in the apoplast by generating reactive oxygen species (ROS) causing oxidative stress. Two defenses exist to restrict the effects of ozone: (i) the stomata which can limit ozone uptake by regulating stomatal conductance and (ii) the detoxification processes of ROS generated by ozone.We studied the effects of ozone (120 ppb) on these two mechanisms of defense in three euramerican poplar genotypes (Populus deltoides x Populus nigra) under controlled conditions in phytotronic chambers. A direct effect of ozone on photosynthesis and stomatal movements in response to changes in environmental factors (by slowing the stomatal opening and closure) has been highlighted. Models of stomatal conductance, on which indicators of critical level of ozone for vegetation are based, must take them into account. In addition, these studies have highlighted the role of constitutive concentrations of antioxidants in tolerance to ozone as well as the complexity of these detoxification mechanisms. The notion of effective ozone flux must consider these two aspects to better characterize the intra-and inter-specific differences in sensitivity to ozone; L'ozone troposphérique est un polluant atmosphérique majeur qui agit comme une phytotoxine. Il pénètre dans les feuilles par les stomates avant d'être dissout dans l'apoplaste en générant des radicaux libres oxygénés (ROS) provoquant ainsi un stress oxydatif. Deux barrières existent pour restreindre les effets de l'ozone : (i) les stomates qui peuvent limiter les flux entrants par contrôle de la conductance stomatique et (ii) le système de détoxication des ROS issus de la dégradation de l'ozone. Nous avons étudié les effets de l'ozone (120 ppb) sur ces deux moyens de défense chez trois génotypes de peuplier euraméricain (Populus deltoides x Populus nigra) placés en conditions contrôlées dans des chambres phytotroniques. Un effet direct de l'ozone sur la photosynthèse et sur les mouvements stomatiques en réponse à des variations de facteurs environnementaux (ralentissement des phénomènes d'ouverture et de fermeture) a été mis en évidence. Les modèles de calcul de la conductance stomatique, sur lesquels se basent les indicateurs de seuil de risque à l'ozone pour la végétation, doivent donc les prendre en compte. De plus, ces travaux ont mis en évidence le rôle prépondérant des concentrations constitutives en antioxidants dans la tolérance à l'ozone ainsi que la complexité de ces mécanismes de détoxication. La notion de flux effectif d'ozone doit prendre en considération ces deux aspects afin de caractériser au mieux les différences de sensibilité à l'ozone intra et inter spécifique
- Published
- 2013
49. Role of stomatal regulation and capacity of foliar detoxification in the estimation of ozone critical level for vegetation
- Author
-
Dumont, Jennifer, Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Université de Lorraine, Didier Le Thiec, and UL, Thèses
- Subjects
[SDV.SA]Life Sciences [q-bio]/Agricultural sciences ,Conductance stomatique ,[SDV]Life Sciences [q-bio] ,fumigation ,stomate ,Stomatal conductance ,Peuplier ,biosynthèse ,Ozone ,[SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry ,Stomates ,Peupliers ,biomasse ,Détoxication ,[SDV.BV]Life Sciences [q-bio]/Vegetal Biology ,[SDV.BV] Life Sciences [q-bio]/Vegetal Biology ,these ,végétation ,molécule ,Plantes -- Effets de l'ozone ,ascorbate ,enzyme ,chlorophylle ,[SDV.SA.SF] Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry ,Detoxification ,Poplar - Abstract
Tropospheric ozone is a major air pollutant that acts as a phytotoxin. It enters the leaf through the stomata before being dissolved in the apoplast by generating reactive oxygen species (ROS) causing oxidative stress. Two defenses exist to restrict the effects of ozone: (i) the stomata which can limit ozone uptake by regulating stomatal conductance and (ii) the detoxification processes of ROS generated by ozone.We studied the effects of ozone (120 ppb) on these two mechanisms of defense in three euramerican poplar genotypes (Populus deltoides x Populus nigra) under controlled conditions in phytotronic chambers. A direct effect of ozone on photosynthesis and stomatal movements in response to changes in environmental factors (by slowing the stomatal opening and closure) has been highlighted. Models of stomatal conductance, on which indicators of critical level of ozone for vegetation are based, must take them into account. In addition, these studies have highlighted the role of constitutive concentrations of antioxidants in tolerance to ozone as well as the complexity of these detoxification mechanisms. The notion of effective ozone flux must consider these two aspects to better characterize the intra-and inter-specific differences in sensitivity to ozone, L'ozone troposphérique est un polluant atmosphérique majeur qui agit comme une phytotoxine. Il pénètre dans les feuilles par les stomates avant d'être dissout dans l'apoplaste en générant des radicaux libres oxygénés (ROS) provoquant ainsi un stress oxydatif. Deux barrières existent pour restreindre les effets de l'ozone : (i) les stomates qui peuvent limiter les flux entrants par contrôle de la conductance stomatique et (ii) le système de détoxication des ROS issus de la dégradation de l'ozone. Nous avons étudié les effets de l'ozone (120 ppb) sur ces deux moyens de défense chez trois génotypes de peuplier euraméricain (Populus deltoides x Populus nigra) placés en conditions contrôlées dans des chambres phytotroniques. Un effet direct de l'ozone sur la photosynthèse et sur les mouvements stomatiques en réponse à des variations de facteurs environnementaux (ralentissement des phénomènes d'ouverture et de fermeture) a été mis en évidence. Les modèles de calcul de la conductance stomatique, sur lesquels se basent les indicateurs de seuil de risque à l'ozone pour la végétation, doivent donc les prendre en compte. De plus, ces travaux ont mis en évidence le rôle prépondérant des concentrations constitutives en antioxidants dans la tolérance à l'ozone ainsi que la complexité de ces mécanismes de détoxication. La notion de flux effectif d'ozone doit prendre en considération ces deux aspects afin de caractériser au mieux les différences de sensibilité à l'ozone intra et inter spécifique
- Published
- 2013
50. Formation des aérosols organiques secondaires (AOS) en lien avec les émissions atmosphériques de la forêt landaise
- Author
-
Kammer, Julien
- Subjects
forêt landaise ,ozone ,monoterpène ,conductance stomatique ,Milieux et Changements globaux ,aérosol organique - Published
- 2013
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