Submitted to: American Journal of Botany
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/25/2012
Publication Date: 11/30/2012
Publication URL: http://handle.nal.usda.gov/10113/56106
Citation: Espeland, E.K., Rice, K.J. 2012. Within- and trans-generational plasticity affects the opportunity for selection in barbed goatgrass (Aegilops Triuncialis). American Journal of Botany. 99(12): 1–5. Interpretive Summary: The environment can affect evolutionary rates within plant populations. In this experiment, we show that a stressful environment slows evolution in an invasive grass species. While the number and weight of seeds produced were the same between stressful and non-stressful environments, the stressful environment resulted in less variation in seed traits. This effect lasted for multiple generations. The research shows that there is a greater evolutionary hurdle to adaptation to stressful environments.
Technical Abstract: Although genetic change can enhance the success of many biological invaders, phenotypic plasticity may also facilitate establishment and spread of introduced species in new environments. To determine if processes influencing the opportunity for selection differ between resource- rich and resource- poor edaphic habitats, we examined within- and trans-generational plasticity in barbed goatgrass on stressful and non-stressful soil types. On stressful soil, both within- and trans-generational plasticity canalized fitness. Canalization from trans-generational plasticity was greater (i.e. 40% reduction in variability for all seed traits) compared to within-generation (i.e. 32% reduction in variability for seed mass only). Although plasticity has often been cited as a factor facilitating the spread of invasive plants, plastic response to stress may actually reduce the opportunity for selection to create adapted ecotypes.