Aquaporin regulation in roots controls plant hydraulic conductance, stomatal conductance, and leaf water potential in Pinus radiata under water stress.
Plant Cell Environ
; 42(2): 717-729, 2019 02.
Article
em En
| MEDLINE
| ID: mdl-30307040
ABSTRACT
Stomatal regulation is crucial for forest species performance and survival on drought-prone sites. We investigated the regulation of root and shoot hydraulics in three Pinus radiata clones exposed to drought stress and its coordination with stomatal conductance (gs ) and leaf water potential (Ψleaf ). All clones experienced a substantial decrease in root-specific root hydraulic conductance (Kroot-r ) in response to the water stress, but leaf-specific shoot hydraulic conductance (Kshoot-l ) did not change in any of the clones. The reduction in Kroot-r caused a decrease in leaf-specific whole-plant hydraulic conductance (Kplant-l ). Among clones, the larger the decrease in Kplant-l , the more stomata closed in response to drought. Rewatering resulted in a quick recovery of Kroot-r and gs . Our results demonstrated that the reduction in Kplant-l , attributed to a down regulation of aquaporin activity in roots, was linked to the isohydric stomatal behaviour, resulting in a nearly constant Ψleaf as water stress started. We concluded that higher Kplant-l is associated with water stress resistance by sustaining a less negative Ψleaf and delaying stomatal closure.
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Base de dados:
MEDLINE
Assunto principal:
Proteínas de Plantas
/
Raízes de Plantas
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Folhas de Planta
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Aquaporinas
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Pinus
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Estômatos de Plantas
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article