Evolution in stressful environments II: adaptive value and costs of plasticity in response to low light in Sinapis arvensis.

摘要: Plants possess a remarkable capacity to alter their phenotype in response the highly heterogeneous light conditions they commonly encounter natural environments. In present study with weedy annual plant Sinapis arvensis, we (a) tested for adaptive value of phenotypic plasticity morphological and life history traits low (b) explored possible fitness costs plasticity. Replicates 31 half-sib families were grown individually greenhouse under full (40% ambient) imposed by neutral shade cloth. Low resulted large increase hypocotyl length specific leaf area (SLA), reduction juvenile biomass delayed onset flowering. Phenotypic selection analysis within each environment revealed that favoured SLA light, but not high suggesting observed was adaptive. contrast, other measured maladaptive (i.e. opposite direction environment). We detected significant additive genetic variance most (number seeds). Using genotypic gradient analysis, found had lower than plasticity, when effect on statistically kept constant. This indicates incurred direct cost. However, cost only expressed light. Thus, models evolution will need incorporate vary magnitude depending environmental conditions.