Collaborative Research: The Evolution of Sex Ratio and Gender in Selfing vs. Outcrossing Clarkia spp. (Onagraceae)

合作研究：Clarkia spp.自交与异交中性别比例和性别的演变。

• 批准号: 9815300
• 负责人: Roger Nisbet
• 金额: $ 22.86万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-01 至 2004-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9815300&HistoricalAwards=false
• 关键词: Collaborative; Research; Evolution; Sex; Ratio

Mazer9815300Flowering plants have evolved a variety of mechanisms that ensure pollination. Many species are "outcrossing", relying on insects to transfer pollen, while others are self-fertilized (each flower pollinates itself). The evolution of self-fertilization from outcrossing ancestors has often had similar outcomes. For example, animal-pollinated outcrossers often produce larger flowers and higher ratios of pollen to ovule production per flower than closely related self-fertilizing species. This study asks: Does natural selection operate as predicted to generate more subtle genetic differences between selfing and outcrossing species? Several predictions will be tested, including that outcrossers are more likely than selfers to exhibit an inverse relationship between the allocation of resources to male vs. female function. Three pairs of closely related outcrossing and self-fertilizing species in the wildflower genus Clarkia will be compared with respect to genetic variation in, and genetically based correlations among, male and female reproductive traits. Greenhouse and field experiments will be conducted to examine constraints on the independent evolution of floral traits in outcrossers vs. selfers.Ten to twelve undergraduate students and one post-doctoral researcher will receive training in evolutionary theory, plant breeding and reproduction, statistical analysis, and the presentation of results. This study will contribute to our understanding of both the potential and limits of natural selection to effect evolutionary changes associated with mating system.

Mazer9815300开花植物进化出了多种确保授粉的机制。 许多物种是“异交”的，依靠昆虫传递花粉，而另一些则是自花受精（每朵花都自己授粉）。 异交祖先的自花受精的进化往往有类似的结果。 例如，动物授粉的异交种通常比近缘的自交种产生更大的花和更高的花粉与胚珠产量比。 这项研究问：自然选择是否如预测的那样在自交和异交物种之间产生更微妙的遗传差异？ 几个预测将进行测试，包括外交比selfers更有可能表现出资源分配男性与女性功能之间的反比关系。 三对密切相关的异交和自交种在野花属Clarkia将进行比较，相对于遗传变异，和基于遗传的相关性，男性和女性的生殖性状。 将进行温室和田间实验，研究异交种与自交种花性状独立进化的限制因素。10至12名本科生和1名博士后研究人员将接受进化理论、植物育种与繁殖、统计分析和结果展示方面的培训。 这项研究将有助于我们了解自然选择的潜力和限制，以影响与交配系统相关的进化变化。