Early signals of water limitations begin at the root-soil interface: linking rhizosphere drying to water uptake decline.

ABSTRACT: Understanding when and where drought stress originates in the soil-plant continuum is essential for predicting plant responses to climate change. While stomatal closure is a well-known reaction to declining soil moisture, the precise hydraulic trigger remains unresolved. We investigated whether the initial reduction in root water uptake is concomitant with a localized depletion of water near the root surface. Using high-resolution neutron radiography, we visualized dynamic changes in water distribution near maize (Zea mays L.) roots under controlled drying. We quantified the shift in water uptake patterns and their impact on whole-plant water use. Under wet conditions, roots primarily extracted water from the bulk soil. As soil moisture declined below a texture-dependent threshold, hydraul

SUBMITTER: Di Bert S 

PROVIDER: S-EPMC12917449 | biostudies-literature | 2026 Mar

REPOSITORIES: biostudies-literature