Reduced drought tolerance during domestication and the evolution of weediness results from tolerance-growth trade-offs.

ABSTRACT: The increased reproductive potential, size, shoot allocation, and growth rate of weedy plants may result from reduced resource allocation to other aspects of plant growth and defense. To investigate whether changes in resource allocation occurred during domestication or the evolution of weediness, we compared the mycorrhizal responsiveness, growth, and drought tolerance of nine native ruderal, nine agriculturally weedy (four U.S. weedy and five Australian weedy), and 14 domesticated populations (eight ancient landraces and six improved cultivars) of the common sunflower (Helianthus annuus). Domesticated sunflower cultivars were less drought tolerant, but had higher plant growth and fecundity and coarser roots than wild populations. There were no changes in level of drought tolerance betwee

SUBMITTER: Koziol L 

PROVIDER: S-EPMC3515206 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature