Journal Article

Abscisic acid down-regulates hydraulic conductance of grapevine leaves in isohydric genotypes only

Tyerman, Stephen, programs LACCAVE; ANR-09-GENM-024-002; Australian Research Council Centre of Excellence in Plant Energy Biology, Edwards, Everard J, Plant Research Centre ; University of Adelaide, 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), Agriculture ; Commonwealth Scientific and Industrial Research Organisation [Australia] (CSIRO), Coupel-Ledru, Aude, Lebon, Eric, Christophe, Angélique, ANR-09-GENM-0024,Vit-Sec,Interactions plantes / virus : identification des facteurs de l'hôte impliqués dans la réplication virale, Masclef, Diane

2017

Overview

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.

• Publisher: Oxford University Press ; American Society of Plant Biologists,CCSD,American Society of Plant Biologists
• Subject: Abscisic Acid - pharmacology / Down-Regulation - drug effects / ECOPHYSIOLOGY AND SUSTAINABILITY / Genetic Variation / Genotype / Life Sciences / Models, Biological / Plant Exudates - metabolism / Plant Leaves - drug effects / Plant Leaves - physiology / Vegetal Biology / Vitis - drug effects / Vitis - genetics / Vitis - physiology / Water - physiology
• ISBN: 0004140525000