Water loss regulation in mature Hevea brasiliensis: effects of intermittent drought in the rainy season and hydraulic regulation
type: Dataset
description: Effects of soil and atmospheric drought on whole-tree transpiration (E-T), leaf water potential (psi(L)) and whole-tree hydraulic conductance (K-T) were investigated in mature rubber trees (Hevea brasiliensis, clone RRIM 600) during the full canopy stage in the rainy season in a drought-prone area of northeast Thailand. Under well-watered soil conditions, transpiration was tightly regulated in response to high evaporative demand, i.e., above reference evapotranspiration (ETo) similar to 2.2 mm day(-1) or maximum vapor pressure deficit similar to 1.8 kPa. When the trees experienced intermittent soil drought E-T decreased sharply when relative extractable water in the top soil was < 0.4. The midday leaf water potential (psi(md)) on sunny days did not change as a function of soil drought and remained stable at approximately -1.95 MPa, i.e., displaying isohydric behavior. The decrease in E-T was mainly due to the change in K-T. K-T remained constant over a wide range of environmental conditions and decreased sharply at low soil water availability. A simple hydraulic model incorporating critical minimum water potential and the response of whole-tree hydraulic conductance to relative extractable water correctly simulated patterns of transpiration over 6 months. We conclude that an explicit and simplified framework of hydraulic limitation hypothesis was sufficient to describe water use regulation of a mature rubber tree stand in water-limited conditions. Given the complexity of constraints in the soil-plant-atmosphere pathway, our results confirm the relevance of this approach to synthesize the overall behavior of trees under drought.
issued: 2026-05-05T21:32:46.594021
language: en
modified: 2026-05-05T21:32:46.594026
contact point: Organization
  fn: CCSD
keyword: conductance
keyword: critical-transpiration
keyword: embolism
keyword: evaporative-demand
keyword: infoeu-reposemanticsarticle
keyword: journal-articles
keyword: leaf
keyword: leaf-water-potential
keyword: plant
keyword: rubber-tree
keyword: sdvsalife-sciences-q-bioagricultural-sciences
keyword: soil
keyword: soil-drought
keyword: stomatal-control
keyword: transpiration
keyword: trees
keyword: vapor-pressure-deficit
keyword: water-relations
keyword: whole-tree-hydraulic-conductance
keyword: xylem-sap-flow
landing page: 0829-318X

Water loss regulation in mature Hevea brasiliensis: effects of intermittent drought in the rainy season and hydraulic regulation
type: Distribution
format: HTML
issued: 2026-05-05T21:32:46.595928
modified: 2026-05-05T21:32:46.558594
access URL: https://hal.science/hal-00964493

test_moissonnage_selune
type: Agent