Given increasing water deficits across numerous ecosystems world‐wide, it is urgent to understand the sequence of failure of leaf function during dehydration. We assessed dehydration‐induced losses of rehydration capacity and maximum quantum yield of the photosystem On average, losses of leaf rehydration capacity occurred at dehydration beyond 50% declines of The stomatal and leaf hydraulic systems show early functional declines before cell integrity is lost. Substantial damage to the photochemical apparatus occurs at extreme dehydration, after complete stomatal closure, and seems to be irreversible.
The widely documented phenomenon of nighttime stomatal conductance We measured Closely related species were more similar in Our results reveal the highest
- NSF-PAR ID:
- 10461148
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 222
- Issue:
- 4
- ISSN:
- 0028-646X
- Format(s):
- Medium: X Size: p. 1778-1788
- Size(s):
- p. 1778-1788
- Sponsoring Org:
- National Science Foundation
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Abstract The fundamental tradeoff between carbon gain and water loss has long been predicted as an evolutionary driver of plant strategies across environments. Nonetheless, challenges in measuring carbon gain and water loss in ways that integrate over leaf lifetime have limited our understanding of the variation in and mechanistic bases of this tradeoff. Furthermore, the microevolution of plant traits within species versus the macroevolution of strategies among closely related species may not be the same, and accordingly, the latter must be addressed using comparative phylogenetic analyses.
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