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
- Award ID(s):
- 2017949
- NSF-PAR ID:
- 10456002
- Date Published:
- Journal Name:
- Global Change Biology
- Volume:
- 29
- Issue:
- 7
- ISSN:
- 1354-1013
- Page Range / eLocation ID:
- 2015 to 2029
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract clones exposed to drought stress and its coordination with stomatal conductance (Pinus radiata g s) and leaf water potential (Ψleaf). All clones experienced a substantial decrease in root‐specific root hydraulic conductance (K root‐r) in response to the water stress, but leaf‐specific shoot hydraulic conductance (K shoot‐l) did not change in any of the clones. The reduction inK root‐rcaused a decrease in leaf‐specific whole‐plant hydraulic conductance (K plant‐l). Among clones, the larger the decrease inK plant‐l, the more stomata closed in response to drought. Rewatering resulted in a quick recovery ofK root‐randg s. Our results demonstrated that the reduction inK plant‐l, attributed to a down regulation of aquaporin activity in roots, was linked to the isohydric stomatal behaviour, resulting in a nearly constant Ψleafas water stress started. We concluded that higherK plant‐lis associated with water stress resistance by sustaining a less negative Ψleafand delaying stomatal closure. -
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