Selfing rate variation among natural populations of Mimulus ringens

Variation in selfing rates within and among populations of hermaphroditic flowering plants can strongly influence the evolution of reproductive strategies and the genetic structure of populations. This intraspecific variation in mating patterns may reflect both genetic and ecological factors, but the relative importance of these factors remains poorly understood. Here we explore how selfing in thirteen natural populations of the perennial wildflower Mimulus ringens is influenced by 1) pollinator visitation, an ecological factor, and 2) floral display, a trait with a genetic component that also responds to environmental variation. We also explore whether genetically based floral traits, including herkogamy, affect selfing. Â Â Â Â Â Â Â Â Â Â Â We found substantial variation among populations in selfing rate (0.13-0.55). Selfing increased strongly and significantly with floral display, among as well as within populations. Selfing also increased at sites with lower pollinator visitation and low ...雌雄同体开花植物种群内部及种群间的自交率变异，可对生殖策略演化与种群遗传结构产生显著影响。这类交配模式的种内变异可能同时受遗传与生态因子共同调控，但目前学界对这些因子的相对重要性仍知之甚少。本研究以多年生野生花卉环沟酸浆（Mimulus ringens）的13个自然种群为研究对象，探讨两类因子对其自交过程的影响：1）传粉者访花这一生态因子；2）花展示——这一兼具遗传基础且可响应环境变异的性状。此外，本研究还探究了包括雌雄异位（herkogamy）在内的遗传基础花部性状是否会对自交率产生影响。 研究发现，不同种群的自交率存在显著差异，取值范围为0.13至0.55。自交率随花展示规模显著升高，该趋势在种群间与种群内部均成立。同时，在传粉者访花频率较低且生境资源匮乏（low ...）的位点，自交率同样有所升高。