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Title: A genotype × environment experiment reveals contrasting response strategies to drought between populations of a keystone species ( Artemisia tridentata ; Asteraceae)
Abstract

Western North America has been experiencing persistent drought exacerbated by climate change for over two decades. This extreme climate event is a clear threat to native plant communities.Artemisia tridentatais a keystone shrub species in western North America and is threatened by climate change, urbanization, and wildfire. A drought Genotype × Environment (G × E) experiment was conducted to assess phenotypic plasticity and differential gene expression inA. tridentata. The G × E experiment was performed on diploidA. tridentataseedlings from two populations (one from Idaho, USA and one from Utah, USA), which experience differing levels of drought stress during the summer months. Photosynthetic data, leaf temperature, and gene expression levels were compared between treatments and populations. The Utah population maintained higher photosynthetic rates and photosynthetic efficiency than the Idaho population under drought stress. The Utah population also exhibited far greater transcriptional plasticity than the Idaho population and expressed genes of response pathways distinct from those of the Idaho population. Populations ofA. tridentatadiffer greatly in their drought response pathways, likely due to differences in response pathways that have evolved under distinct climatic regimes. Epigenetic processes likely contribute to the observed differences between the populations.

 
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Award ID(s):
1757324
NSF-PAR ID:
10495579
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Plant-Environment Interactions
Volume:
4
Issue:
4
ISSN:
2575-6265
Page Range / eLocation ID:
201 to 214
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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