COLLAB. RES.:Relative Fitness and Gender in Wild Populationsof Spergulaic marina (the sand-spurrey: Caryophyllaceae): AnExamination of the Assumptions of Theoretical Models

协作。

• 批准号: 9106647
• 负责人: Susan Mazer
• 金额: $ 6.77万
• 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: 1992
• 资助国家: 美国
• 起止时间: 1992-01-01 至 1994-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9106647&HistoricalAwards=false
• 关键词: COLLAB.; RES.; Relative; Fitness; Gender

Sand-spurrey, Spergularia marina, is a common species of natural coastal wetland habitats throughout the world. Like most plant species, flowers of S. marina produce both male and female gametes through the production of pollen grains and ovules. However, in contrast to most species, S. marina exhibits ten-fold variation in pollen production, which represents allocation to male reproduction. In addition, S. marina individuals show three-fold variation in average ovule production (from 50 to 150 ovules per flower), although this range of variation is not uncommon in flowering plants. More importantly, the variation in both stamen number and ovule number has a genetic basic and is thus likely to show change over time in response to selection. This species, therefore, provides an excellent opportunity to investigate the causes and consequences of variation in the allocation of floral resources to male and female gametes, commonly known as "gender allocation". Currently, although there exists a great deal of theoretical work on this topic, there are no empirical studies that explore thoroughly the assumptions of this theory. For example, it has long been believed that selection to increase male allocation (e.g. high pollen production) should necessarily result in a reduction in female allocation (e.g., reduced ovule or deed production), promoting the evolution of specialized reproductive systems. This assumption, however, has never been adequately tested. Our study of the ecological genetics of sand-spurrey will test the assumptions of gender allocation theory by providing measurements of the genetic component to stamen and ovule production and measurements of any "costs" associated with increased allocation to male or female reproduction. Moreover, our data will allow an evaluation of the evolutionary flexibility of S. marina - and species similar to it - and its ability to alter its productive biology in response to changes in its increasingly threatened habitat.

沙鲷，Spergularia marina，是一种常见的物种 自然海岸湿地栖息地遍布世界各地。 像大多数 植物种类、花的种类。码头生产男性和女性 配子通过产生花粉粒和胚珠。 然而，与大多数物种相比，S.玛丽娜展示了十倍于 花粉生产的变化，这代表了分配给 男性生殖 此外，S. Marina个人秀 平均胚珠产量的三倍变化（从50到150 胚珠每花），虽然这种变化范围不是 在开花植物中不常见。 更重要的是， 雄蕊数和胚珠数都有遗传基础， 因此可能响应于选择而显示随时间的变化。 因此，这个物种提供了一个极好的机会， 调查变化的原因和后果， 将花资源分配给雄配子和雌配子， 通常称为“性别分配”。 目前，虽然有 在这个问题上有大量的理论工作， 没有实证研究，探索彻底的假设， 这个理论。 例如，人们一直认为， 增加雄性分配的选择（例如高花粉 生产）必然会导致女性减少 分配（例如，减少胚珠或契约生产），促进 专门生殖系统的进化。 这 然而，这一假设从未得到充分的检验。 本研究将对沙枣的生态遗传学研究起到一定的指导作用。 测试性别分配理论的假设， 雄蕊和胚珠遗传成分的测定 生产和计量与下列方面有关的任何“成本”： 增加分配给男性或女性生殖。 此外，委员会认为， 我们的数据将允许评估进化的灵活性 色葡萄以及与之相似的物种， 改变其生产性生物学，以应对其 日益受到威胁的栖息地。