DISSERTATION RESEARCH: Examining conflicting selection pressures on floral morphology of Silene stellata by the pollinating seed predator Hadena ectypa

动物传粉者被认为对它们授粉的花的不同结构产生相互冲突的选择压力。本研究将探讨一种夜行飞蛾（Hadena ectypa）对天然多年生草本植物星芒草（Silene stellata）的雄蕊和雌蕊的不同选择压力。这是一项开创性的研究，在两性植物物种中，对花形态不同方面的相互冲突的选择压力进行了大量未开发的领域，并将为花多样性的进化提供有价值的见解。此外，本项目将测试和优化一种遗传技术的应用，以估计花粉供体的繁殖成功率。该项目为研究生提供了良好的培训机会，也将涉及到分子生物学和遗传学方面的几名本科生研究助理和高中实习生。本研究将在连续两年的野外实验基础上，研究星芒花雄蕊和雌蕊的表型选择。本项目将开发和利用24个高可变微卫星遗传标记，对231个标记成虫种群中萌发的2138株花粉供体的繁殖成功率进行评估。然后通过确定幼苗和成体植株的多位点基因型来估计花粉供体的成功。高分辨率的基因分型需要在四倍体中确定花粉供体的身份，这需要开发额外的遗传标记。这些新的标记将有助于未来对星丝莲的遗传研究，并将为其他研究人员研究鲜为人知的多倍体物种的遗传提供一种模型方法。

Animal pollinators are thought to produce conflicting selective pressures on different structures within the flowers they pollinate. This study will investigate the differing selection pressures on stamens and pistils within flowers of Silene stellata, a native perennial herb, by Hadena ectypa, a nocturnal moth that acts as a pollinator as well as a seed predator of Silene. This is a pioneering study into the largely unexplored area of conflicting selective pressures on different aspects of floral morphology within a hermaphroditic plant species and will provide valuable insights into the evolution of floral diversity. In addition, this project will test and optimize the application of a genetic technique to estimate reproductive success of the pollen donor. The project provides excellent training opportunities for the graduate student and will also involve several undergraduate research assistants and high school interns in all of molecular biology and genetic aspects.This research will build on two successive years of field experiments to investigate phenotypic selection on stamens and pistils in flowers of Silene stellata, This project will develop and employ 24 highly variable microsatellite genetic markers to assess reproductive success of the pollen donor within 2138 seedlings germinated from a population of 231 tagged adult individuals. Success of the pollen donor will then be estimated by determining the multi-locus genotypes of the seedlings and the adult plants. The high resolution genotyping required to determine the identity of the pollen donor within a tetraploid such as Silene stellata necessitates the development of additional genetic markers. These new markers will facilitate future genetic studies of Silene stellata and will provide a model approach for other researchers investigating the genetics of poorly known, polyploidy species.