The Sequence of Drought-Driven Stomatal Closure, Stem Xylem Embolism, Dehydration, and Aquaporin Gene Expression Differs Among Species.

ABSTRACT: Stem dehydration is critical in predicting drought-driven tree mortality. Yet, how it coordinates with stomatal closure, xylem embolism, and aquaporin-mediated water transport regulation remains unknown. Two angiosperms (beech and olive) and two conifers (pine and juniper) of contrasted embolism resistance were selected to assess the sequence of drought-driven responses. Leaf stomatal conductance, stem hydraulic conductivity, and dehydration of elastic tissues (via stem radial variations) were monitored across a gradient of stem water potential to fit the corresponding percentage loss curves. Leaf pressure-volume curves and aquaporin gene (PIP) expression in lateral branches were also measured. Stomatal closure was the first response to drought across species. Loss of hydraulic conductivit

SUBMITTER: Salomon RL 

PROVIDER: S-EPMC12583245 | biostudies-literature | 2025 Nov-Dec

REPOSITORIES: biostudies-literature