Drought resistance in oat involves ABA-mediated modulation of transpiration and root hydraulic conductivity

Drought is one of the most important constraints to crop productivity worldwide. Control of plant responses to drought is very complex. The mechanisms and their intensity may differ between species and/or genotypes ultimately conditioning tolerance or susceptibility. We explore here the strategy set...

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Detalles Bibliográficos
Autores: Canales, Francisco José, Rispail, Nicolas, García-Tejera, Omar, Arbona, Vicent, Pérez de Luque, Alejandro, Prats, Elena
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2021
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/241450
Acceso en línea:http://hdl.handle.net/10261/241450
Access Level:acceso abierto
Palabra clave:Abscisic acid
Drought
Hydraulic conductance
Oat
Root morphology
Transpiration
Descripción
Sumario:Drought is one of the most important constraints to crop productivity worldwide. Control of plant responses to drought is very complex. The mechanisms and their intensity may differ between species and/or genotypes ultimately conditioning tolerance or susceptibility. We explore here the strategy set up by two oat cultivars to cope with drought based on root morphological, anatomical, physiological and molecular studies. A dramatic and rapid abscisic acid increase in the susceptible genotype resulted in a tight and rapid reduction of stomatal conductance. Despite of this, leaf water potential decreased concomitantly due to a decrease in root hydraulic conductivity. By contrast, the resistant genotype, showed a mild and slow increase in abscisic acid that allowed maintaining transpiration longer. This response was linked to an increase in root hydraulic conductance through an increase in total root length and in the length of the thinnest roots as well as a rise in root conductivity. This was also coupled with anatomical changes leading to a reduction of metabolic cost. These changes allowed the resistant genotype to maintain higher water potential reducing drought symptoms and promoting growth under water deficit conditions.