Adaptive Value of Phenological Traits in Stressful Environments: Predictions Based on Seed Production and Laboratory Natural Selection

摘要: Phenological traits often show variation within and among natural populations of annual plants. Nevertheless, the adaptive value post-anthesis is seldom tested. In this study, we estimated values pre- in two stressful environments (water stress interspecific competition), using selfing species Arabidopsis thaliana. By estimating seed production by performing laboratory selection (LNS), assessed strength nature (directional, disruptive stabilizing) acting on phenological A. thaliana under tested conditions, each with four intensities. Both type its intensity affected selection, as did genetic constraints traits. Under water stress, both experimental approaches demonstrated directional for a shorter life cycle, although bolting time imposes constraint length interval between anthesis. competition, results from showed discrepancies. Estimation predicted toward early pre-anthesis long periods. contrast, LNS approach suggested neutrality all This study opens questions adaptation complex environment where many selective pressures act simultaneously.