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

论文研究：检验授粉种子捕食者 Hadena ectypa 对 Silene stellata 花形态的相互冲突的选择压力

• 批准号: 1501799
• 负责人: Charles Fenster
• 金额: $ 1.94万
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-05-01 至 2017-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1501799&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Examining; conflicting; selection

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.

人们认为动物传粉媒介会对它们授粉的花朵内的不同结构产生相互冲突的选择压力。这项研究将调查 Hadena ectypa（一种夜间活动的飞蛾，既是 Silene 的传粉者，又是 Silene 的种子捕食者）对本土多年生草本植物 Silene stellata 花中雄蕊和雌蕊的不同选择压力。这是一项开创性的研究，涉及雌雄同体植物物种内花卉形态不同方面的相互冲突的选择压力，这一领域在很大程度上尚未被探索，将为花卉多样性的进化提供有价值的见解。此外，该项目将测试和优化遗传技术的应用，以估计花粉供体的繁殖成功率。该项目为研究生提供了极好的培训机会，还将涉及所有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。这项研究将建立在连续两年的现场实验的基础上，以研究雄蕊和雌蕊的表型选择在 Silene stellata 的花朵中，该项目将开发和使用 24 个高度可变的微卫星遗传标记，以评估花粉供体在从 231 个种群中萌发的 2138 个幼苗中的繁殖成功率标记成年个体。然后通过确定幼苗和成年植物的多基因座基因型来估计花粉供体的成功。 确定四倍体（例如 Silene stellata）内花粉供体的身份所需的高分辨率基因分型需要开发额外的遗传标记。 这些新标记将促进未来对 Silene stellata 的遗传学研究，并为其他研究鲜为人知的多倍体物种遗传学的研究人员提供模型方法。