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Title: Rapid drought‐recovery of gas exchange in Caragana species adapted to low mean annual precipitation
Abstract While variation in mean annual precipitation (MAP) of the native habitat of a species has been shown to determine the ability of a species to resist a hydraulic decrease during drought, it remains unknown whether these variations in MAP also influence the ability of a species to recover and survive drought. Leaf hydraulic and gas exchange recovery following drought and the underlying mechanisms of these responses in sixCaraganaspecies from habitats along a large precipitation gradient were investigated during rehydration in a common garden. The gas exchange of species from arid habitats recovered more rapidly during rehydration after mild, moderate and severe drought stress treatments than species from humid habitats. The recovery of gas exchange was not associated with foliar abscisic acid concentration, but tightly related to the recovery of leaf hydraulic conductance (Kleaf). The recovery ofKleafwas associated with the loss ofKleafduring dehydration under mild and moderate drought stress, and to leaf xylem embolism formation under severe drought stress. Results pointed to the different ability to recover in gas exchange in sixCaraganaspecies post‐drought is associated with the MAP of the species in its native habitat.  more » « less
Award ID(s):
1943583
PAR ID:
10511118
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Plant, Cell and Environment
Date Published:
Journal Name:
Plant, Cell & Environment
Volume:
46
Issue:
8
ISSN:
0140-7791
Page Range / eLocation ID:
2296 to 2309
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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