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Title: Resolving the contrasting leaf hydraulic adaptation of C3 and C4 grasses
Summary Grasses are exceptionally productive, yet their hydraulic adaptation is paradoxical. Among C3grasses, a high photosynthetic rate (Aarea) may depend on higher vein density (Dv) and hydraulic conductance (Kleaf). However, the higherDvof C4grasses suggests a hydraulic surplus, given their reduced need for highKleafresulting from lower stomatal conductance (gs).Combining hydraulic and photosynthetic physiological data for diverse common garden C3and C4species with data for 332 species from the published literature, and mechanistic modeling, we validated a framework for linkages of photosynthesis with hydraulic transport, anatomy, and adaptation to aridity.C3and C4grasses had similarKleafin our common garden, but C4grasses had higherKleafthan C3species in our meta‐analysis. Variation inKleafdepended on outside‐xylem pathways. C4grasses have highKleaf : gs, which modeling shows is essential to achieve their photosynthetic advantage.Across C3grasses, higherAareawas associated with higherKleaf, and adaptation to aridity, whereas for C4species, adaptation to aridity was associated with higherKleaf : gs. These associations are consistent with adaptation for stress avoidance.Hydraulic traits are a critical element of evolutionary and ecological success in C3and C4grasses and are crucial avenues for crop design and ecological forecasting.  more » « less
Award ID(s):
1943583 2017949
PAR ID:
10595474
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
New Phytologist
Date Published:
Journal Name:
New Phytologist
Volume:
245
Issue:
5
ISSN:
0028-646X
Page Range / eLocation ID:
1924 to 1939
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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