Dissertation Research: Selection, niche breadth and plant mating system evolution: Are wider niche breadths of selfing species shaped by water limitation?

论文研究：选择、生态位宽度和植物交配系统进化：自交物种更宽的生态位宽度是否受到水分限制的影响？

• 批准号: 1701947
• 负责人: Susan Kalisz
• 金额: $ 1.96万
• 依托单位: University of Tennessee Knoxville
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-06-01 至 2018-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1701947&HistoricalAwards=false
• 关键词: Dissertation; Research; Selection; niche; breadth; Dissertation; Research; Selection; niche; breadth

This project will investigate whether the type of plant mating system contributes to whether a plant can survive in stressful habitats. Plant mating systems, which range from self-pollinating to outcross-pollinating, where pollen has to be moved among different plants for fertilization to happen, can have significant effects on where wild plant species live. Self-pollinating species are expected to be better than outcrossing species at colonizing new areas because they do not require the presence of either pollinators or mates. This study will test the hypothesis that self-pollinating species also have physiological advantages that allow them to outperform outcrossing species in stressful, water-limited environments. The researchers will collect and analyze a variety of physiological data, such as growth rate and relative fitness, from multiple, closely-related pairs of selfing and outcrossing Collinsia plants. Results of this work will reveal important factors influencing the evolution of plant mating systems. In addition, the project will involve mentoring of undergraduate students, including individuals from groups that are underrepresented in the sciences. Planned outreach activities include the development of educational activities for elementary school children. Recent findings support theoretical models that suggest selfing may be a niche diversifying trait because it allows colonization of new habitats lacking pollinators or mates. The proposed research builds on previous results on mating systems and niche breadth by testing whether the physiological performance of selfing species relative to outcrossers contribute to the observed repeated patterns of niche breadth differentiation between sister species pairs in the genus Collinsia. To test the hypothesis that selfers are better adapted to water-limited environments, the investigators will measure drought stress by comparing the ratio of stable isotopes 13C:12C in herbarium leaf samples of selfing/outcrossing sister species pairs relative to the 13C:12C in the international standard. They will also grow three selfing/outcrossing sister species pairs in the greenhouse in both high water and water-limited treatments and measure physiological, growth, and reproductive trait responses. Results will have important implications for our understanding of the evolution and maintenance of niche breadth.

该项目将研究工厂交配系统的类型是否有助于植物在压力大的栖息地中生存。植物交配系统的范围从自我授粉到脱覆粉，在这些植物之间必须在不同的植物中移动花粉才能发生，可能会对野生植物物种居住的地方产生重大影响。预计自我授粉物种比在新区域殖民地的杂交物种要好，因为它们不需要授粉媒介或伴侣的存在。这项研究将检验以下假设：自我授粉物种还具有生理优势，使它们能够在压力大的，有限的环境中胜过淘汰物种。研究人员将从多对紧密相关的自我自我和杂交植物收集和分析各种生理数据，例如增长率和相对适应性。这项工作的结果将揭示影响植物交配系统发展的重要因素。此外，该项目将涉及指导本科生，包括来自科学中人数不足的团体的个人。计划的外展活动包括开发小学儿童的教育活动。最近的发现支持理论模型，表明自学可能是一个多元化的特征，因为它允许殖民缺乏授粉媒介或伴侣的新栖息地。拟议的研究通过测试自我物种相对于露出者的生理表现是否有助于观察到的collinsia姐妹物种对之间观察到的利基广度分化的重复模式来建立对交配系统和利基广度的先前结果。为了测试自我更好地适应水限制环境的假设，研究人员将通过比较稳定的同位素13c：12c的比例在国际标准中相对于13c：12c的稳定同位素13c：12c。他们还将在高水和水限制的温室中种植三种自我自我/脱落的姊妹物种对，并测量生理，生长和生殖性状反应。结果将对我们对利基广度的演变和维持的理解具有重要意义。