Amanda M. Kenney, John K. McKay, James H. Richards and Thomas E. Juenger
Using a combination of experimental manipulation, quantitative genetics, and genetic selection analyses, we investigated the evolutionary significance of natural genetic variation in water-use efficiency (WUE), flowering time, and WUE plasticity to drought in spring flowering accessions of Arabidopsis thaliana. Our results indicate that strong genetic correlation between WUE and flowering time may facilitate the evolution of drought escape, or constrain independent evolution of these traits. Terminal drought favored drought escape (earlier flowering and lower WUE), rather than a more conservative avoidance strategy in these spring flowering accessions of A. thaliana. Finally, WUE plasticity to drought may be favored over completely fixed development in environments with periodic drought.