Dissertation Research: Comparing Prezygotic Isolating Mechanisms in Unimodal and Bimodal Plant Hybrid Zones.

论文研究：比较单峰和双峰植物杂交区的合子前隔离机制。

• 批准号: 0206279
• 负责人: Diane Campbell
• 金额: $ 0.99万
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-06-15 至 2004-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0206279&HistoricalAwards=false
• 关键词: Dissertation; Research; Comparing; Prezygotic; Isolating

This study assesses the relative importance of ecological and genetic mechanisms that restrict natural hybridization in plants. Two closely related species of Ipomopsis plants grow in close proximity in several sites in the mountains of the western U.S. By comparing contact sites where hybrids are common with a contact site where the same two species do not hybridize successfully and instead form a bimodal distribution of morphologies, it is possible to investigate the importance of different isolating mechanisms to the rate of hybridization. Sites with low versus high frequencies of hybrids will be compared with respect to the degree of introgression of genes using molecular methods. Behavior of bird and insect pollinators will be examined at each site to test for differences in gene flow induced by behavioral choices or ability of pollinators to transfer pollen. Experimental pollinations will test for differences in the competitive ability of pollen from another species.Hybridization rates vary tremendously across different taxonomic groups. Understanding the reasons why will contribute to an understanding of the fundamental problem of how species differences and biological diversity are maintained. It could also help in predicting impacts of hybridization with genetically engineered crops or with invasive plant species.

这项研究评估了限制植物自然杂交的生态和遗传机制的相对重要性。 通过比较杂交常见的接触位点与相同的两个物种未成功杂交而形成形态双峰分布的接触位点，两种密切相关的白松属植物物种在美国西部山区的几个地点生长得很接近。 ，可以研究不同分离机制对杂交率的重要性。 将使用分子方法比较具有低频率和高频率杂种的位点的基因渗入程度。将在每个地点检查鸟类和昆虫传粉媒介的行为，以测试由行为选择或传粉媒介转移花粉的能力引起的基因流差异。 实验授粉将测试来自另一个物种的花粉竞争能力的差异。不同分类群体的杂交率差异很大。 了解其原因将有助于理解如何维持物种差异和生物多样性的基本问题。 它还可以帮助预测与转基因作物或入侵植物物种杂交的影响。