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Title: Phylogenetic and biogeographic controls of plant nighttime stomatal conductance
Summary

The widely documented phenomenon of nighttime stomatal conductancegsncould lead to substantial water loss with no carbon gain, and thus it remains unclear whether nighttime stomatal conductance confers a functional advantage. Given that studies ofgsnhave focused on controlled environments or small numbers of species in natural environments, a broad phylogenetic and biogeographic context could provide insights into potential adaptive benefits ofgsn.

We measuredgsnon a diverse suite of species (n = 73) across various functional groups and climates‐of‐origin in a common garden to study the phylogenetic and biogeographic/climatic controls ongsnand further assessed the degree to whichgsnco‐varied with leaf functional traits and daytime gas‐exchange rates.

Closely related species were more similar ingsnthan expected by chance. Herbaceous species had highergsnthan woody species. Species that typically grow in climates with lower mean annual precipitation – where the fitness cost of water loss should be the highest – generally had highergsn.

Our results reveal the highestgsnrates in species from environments where neighboring plants compete most strongly for water, suggesting a possible role for the competitive advantage ofgsn.

 
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NSF-PAR ID:
10461148
Author(s) / Creator(s):
 ;  ;  ;  
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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