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Title: Balancing growth amidst salt stress – lifestyle perspectives from the extremophyte model Schrenkiella parvula
SUMMARY

Schrenkiella parvula, a leading extremophyte model in Brassicaceae, can grow and complete its lifecycle under multiple environmental stresses, including high salinity. Yet, the key physiological and structural traits underlying its stress‐adapted lifestyle are unknown along with trade‐offs when surviving salt stress at the expense of growth and reproduction. We aimed to identify the influential adaptive trait responses that lead to stress‐resilient and uncompromised growth across developmental stages when treated with salt at levels known to inhibit growth in Arabidopsis and most crops. Its resilient growth was promoted by traits that synergistically allowed primary root growth in seedlings, the expansion of xylem vessels across the root‐shoot continuum, and a high capacity to maintain tissue water levels by developing thicker succulent leaves while enabling photosynthesis during salt stress. A successful transition from vegetative to reproductive phase was initiated by salt‐induced early flowering, resulting in viable seeds. Self‐fertilization in salt‐induced early flowering was dependent upon filament elongation in flowers otherwise aborted in the absence of salt during comparable plant ages. The maintenance of leaf water status promoting growth, and early flowering to ensure reproductive success in a changing environment, were among the most influential traits that contributed to the extremophytic lifestyle ofS. parvula.

 
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Award ID(s):
1923589 1616827
NSF-PAR ID:
10445373
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  more » ;  ;  ;  ;  ;  ;  ;  ;  ;   « less
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
The Plant Journal
Volume:
116
Issue:
3
ISSN:
0960-7412
Format(s):
Medium: X Size: p. 921-941
Size(s):
["p. 921-941"]
Sponsoring Org:
National Science Foundation
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