Aluminum prevents stomatal conductance from responding to vapor pressure deficit in Citrus limonia

Autor(es)

Silva, Giselle Schwab ^[1] ; Gavassi, Marina Alves ^[1] ; Nogueira, Matheus Armelin ^[1] ; Habermann, Gustavo ^[2]

Afiliação do(s) autor(es)

^[1] Univ Estadual Paulista UNESP, Programa Posgrad Biol Vegetal, Inst Biociencias, Dept Bot, Av 24-A, 1515, BR-13506900 Rio Claro, SP - Brazil

^[2] Univ Estadual Paulista UNESP, Dept Bot, Inst Biociencias, Av 24-A, 1515, BR-13506900 Rio Claro, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ENVIRONMENTAL AND EXPERIMENTAL BOTANY; v. 155, p. 662-671, NOV 2018.
• Citações Web of Science: 4

Resumo

Stomatal aperture generally increases in response to low vapor pressure deficit (VPD) and decreases at high VPD. Aluminum (Al) inhibits root growth, indirectly exposing the roots to low water availability, which may decrease leaf hydration and, consequently, the stomatal conductance (gs). In this study, Citrus limonia ('Rangpue lime) was grown in nutrient solution with 1480 mu M Al for 90 days, and we expected that the presence of Al could prevent gs from responding to VPD. As expected, gs did not respond to the increase in VPD in plants exposed to Al. Aluminum also reduced the relative water content and midday leaf water potential ('ffnid) after 60 and 90 days. The CO2 assimilation rate (A) followed the same response pattern exhibited by gs, the estimation of the carboxylation efficiency was not reduced in plants exposed to Al and measured under drier air, while photochemical responses were slightly reduced in plants exposed to Al, indicating that the Al-induced decrease in A was dependent on gs and less ascribed to low photochemical performance. Like in drought conditions, the longterm exposure to Al reduces leaf hydration and compromises gs responses to the atmosphere, eventually impairing A in `Rangpue lime plants. (AU)

• Processo FAPESP: 15/25409-4 - Papel do ABA nas relações hídricas em metabolismos contrastantes à sensibilidade ao Al3+
• Beneficiário: Marina Alves Gavassi
• Modalidade de apoio: Bolsas no Brasil - Doutorado