title: Developmental priming of stomatal sensitivity to abscisic acid by leaf microclimate.
abstract: Plant water loss and CO2 uptake are controlled by valve-like structures on the leaf surface known as stomata. Stomatal aperture is regulated by hormonal and environmental signals. We show here that stomatal sensitivity to the drought hormone abscisic acid (ABA) is acquired during leaf development by exposure to an increasingly dryer atmosphere in the rosette plant Arabidopsis. Young leaves, which develop in the center of the rosette, do not close in response to ABA. As the leaves increase in size, they are naturally exposed to increasingly dry air as a consequence of the spatial arrangement of the leaves, and this triggers the acquisition of ABA sensitivity. Interestingly, stomatal ABA sensitivity in young leaves is rapidly restored upon water stress. These findings shed new light on how plant architecture and stomatal physiology have coevolved to optimize carbon gain against water loss in stressing environments.
authors.affiliation: UMR 759, Laboratoire d'Ecophysiologie des Plantes sous Stress Environnementaux, INRA - Montpellier SupAgro, 34060 Montpellier, France.
authors.forename: Florent
authors.initials: F
authors.lastname: Pantin
authors.forename: Jeanne
authors.initials: J
authors.lastname: Renaud
authors.forename: François
authors.initials: F
authors.lastname: Barbier
authors.forename: Alain
authors.initials: A
authors.lastname: Vavasseur
authors.forename: Didier
authors.initials: D
authors.lastname: Le Thiec
authors.forename: Christophe
authors.initials: C
authors.lastname: Rose
authors.forename: Thierry
authors.initials: T
authors.lastname: Bariac
authors.forename: Stuart
authors.initials: S
authors.lastname: Casson
authors.forename: Deirdre H
authors.initials: DH
authors.lastname: McLachlan
authors.forename: Alistair M
authors.initials: AM
authors.lastname: Hetherington
authors.forename: Bertrand
authors.initials: B
authors.lastname: Muller
authors.forename: Thierry
authors.initials: T
authors.lastname: Simonneau
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D017360:Arabidopsis / Q000187:drug effects / Q000254:growth & development / Q000502:physiology*; D003890:Desiccation; D008834:Microclimate; D018515:Plant Leaves / Q000187:drug effects / Q000254:growth & development / Q000502:physiology; D054046:Plant Stomata / Q000187:drug effects / Q000502:physiology*; D018526:Plant Transpiration; D013312:Stress, Physiological; D014867:Water / Q000378:metabolism
chemical_list: D014867:Water; D000040:Abscisic Acid