Flowering time and water‐use efficiency (
Cultivated crops are generally expected to have less abiotic stress tolerance than their wild relatives. However, this assumption is not well supported by empirical literature and may depend on the type of stress and how it is imposed, as well as the measure of tolerance being used. Here, we investigated whether wild and cultivated accessions of
- PAR ID:
- 10499149
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Plant Direct
- Volume:
- 8
- Issue:
- 4
- ISSN:
- 2475-4455
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract WUE ) are two ecological traits that are important for plant drought response. To understand the evolutionary significance of natural genetic variation in flowering time,WUE , andWUE plasticity to drought inArabidopsis thaliana , we addressed the following questions: (1) How are ecophysiological traits genetically correlated within and between different soil moisture environments? (2) Does terminal drought select for early flowering and drought escape? (3) IsWUE plasticity to drought adaptive and/or costly? We measured a suite of ecophysiological and reproductive traits on 234 spring flowering accessions ofA. thaliana grown in well‐watered and season‐ending soil drying treatments, and quantified patterns of genetic variation, correlation, and selection within each treatment.WUE and flowering time were consistently positively genetically correlated.WUE was correlated withWUE plasticity, but the direction changed between treatments. Selection generally favored early flowering and lowWUE , with drought favoring earlier flowering significantly more than well‐watered conditions. Selection for lowerWUE was marginally stronger under drought. There were no net fitness costs ofWUE plasticity.WUE plasticity (per se) was globally neutral, but locally favored under drought. Strong genetic correlation betweenWUE and flowering time may facilitate the evolution of drought escape, or constrain independent evolution of these traits. Terminal drought favored drought escape in these spring flowering accessions ofA. thaliana .WUE plasticity may be favored over completely fixed development in environments with periodic drought. -
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