DISSERTATION RESEARCH: Assessing the General Importance of Frequency-Dependent Selection in Plant Breeding Systems.

人们早就认识到，交配类型的成功取决于它在种群中的频率。尽管存在一些频率依赖选择的经验例子，但它在植物交配进化动力学中的普遍重要性尚未得到证实。这项拟议的研究将以卡罗琳茄子(Solanum Carolinense)--一种在个体内同时携带雄花和两性花的物种--作为一个模式系统来回答：i)通过适合度的雌性和雄性成分对雄性花的相对产量起作用的选择模式是什么？Ii)选择作用于这个性状是否像理论预测的那样依赖于频率？Iii)如果是这样的话，这种频率依赖的选择是否解释了自然种群中保持中等比例的雄花？这些问题将通过田间和温室实验以及单个植物的遗传指纹图谱来解决。这一建议的智力价值在于检验了有性理论中的一个基本预测，即对雄性偏向分配的选择是取决于频率的，从而有助于更彻底地了解植物交配系统所需的信息。该项目的广泛影响将通过鼓励不同群体的参与来加强学术界，特别是对科学感兴趣的本科生和拉丁裔学生。

It has been long recognized that the success of a mating type depends on its frequency in the population. Although a few empirical examples of frequency-dependent selection exist, its general importance in the evolutionary dynamics of plant mating has yet to be documented. The proposed study will use Solanum carolinense, a species that carries both male and hermaphroditic flowers within individuals, as a model system to answer: i) What is the pattern of selection acting through both female and male components of fitness on the relative production of male flowers? ii) Is selection acting on this trait frequency-dependent, as predicted by theory? iii) If so, does this frequencydependent selection explain the maintenance of intermediate proportions of male flowers in natural populations? These questions will be addressed through a combination of field and greenhouse experiments, and genetic fingerprinting of individual plants. The intellectual merit of this proposal is to test a fundamental prediction in sexual theory, i.e. that selection on male-biased allocation is frequency-dependent, thus contributing information needed for a more thorough understanding of plant mating systems. The broader impact of this project will enhance the academic community by encouraging the participation of diverse groups, particularly undergraduate and Latino students with an interest in science.