DISSERTATION RESEARCH: Genome-Wide Analysis of Recent Hybridization Among Switchgrass Ecotypes

在许多植物中，遗传上不同的群体的杂交是一种重要的自然现象，可以产生新的物种，并将有益的性状从一个群体转移到另一个群体。大多数植物，包括许多生态和经济上重要的物种，都缺乏遗传信息，如哪些基因和多少基因影响杂交。这项研究将使用最先进的DNA测序方法来研究柳枝稷（一种原产于北美的多年生高草）的两种生态型（适应不同栖息地的遗传上不同的品种）的自然杂交。这些DNA测序方法产生的数据比以前多数百倍，从而能够分析柳枝稷的整个基因组，而不仅仅是少数基因。这些数据将用于识别杂交种群，分析迁移模式，并确定柳枝稷基因组中在生态型之间转移或降低杂交成功率的区域。柳枝稷是一种新兴的生物能源作物，也是土地保护中应用最广泛的物种之一。本项目中确定的遗传变异和杂交模式将对选择适当的柳枝稷品种用于生物能源生产和保护需求产生直接影响。此外，特征的杂交群体将是宝贵的资源，为未来的工作，确定影响经济上重要的生物能源性状的基因。除了生物能源和保护的影响，这一建议将作为一个模板，在其他生态和/或经济上重要的物种，如柳枝稷，没有传统模式生物的研究资源，实施新的基因分型方法。

The hybridization of genetically distinct groups is an important, natural occurrence in many plants that can generate new species and transfer beneficial traits from one group to another. Genetic information, such as which and how many genes affect hybridization, is lacking for most plants, including many ecologically and economically important species. This research will use state-of-the-art DNA sequencing methods to examine the natural hybridization of two ecotypes (genetically distinct varieties adapted to different habitats) of switchgrass, a perennial tallgrass native to North America. These DNA sequencing methods generate hundreds of times more data than previously possible, thus enabling analyses across the entire genome of switchgrass rather than just a handful of genes. The data will be used to identify hybrid populations, analyze patterns of migration, and identify regions in the switchgrass genome that are being transferred between ecotypes or that decrease the success of hybrids. Switchgrass is an emerging bioenergy crop and one of the most widely used species for land conservation. The patterns of genetic variation and hybridization identified in this project will have direct implications on selecting appropriate varieties of switchgrass for bioenergy production and conservation needs. Additionally, the characterized hybrid populations will be valuable resources for future work identifying genes that affect economically important bioenergy traits. Beyond the bioenergy and conservation implications, this proposal will act as a template for implementing new genotyping methods in other ecologically and/or economically important species that, like switchgrass, do not have the research resources of traditional model organisms.