DISSERTATION RESEARCH: Evolution of polyploidy and storage roots in sweet potato and its wild relatives

论文研究：甘薯及其野生近缘种多倍体和贮藏根的进化

• 批准号: 1601251
• 负责人: James Leebens-Mack
• 金额: $ 1.91万
• 依托单位: University of Georgia Research Foundation Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-01 至 2018-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1601251&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Evolution; polyploidy; storage

Sweet potato, with its carbohydrate- and vitamin-rich storage roots, is a vital source of nutrition for people in many countries. Current efforts to improve crop yield in sweet potato are focused on a small number of breeding lines. Wild relatives of crop species can also be an important source of genetic material for crop improvement, but the evolutionary relationships between sweet potato and its wild relatives are currently unknown. This project will use genomic data to reconstruct evolutionary relationships between sweet potato and its wild relatives, and shed light on the genetic changes that have contributed to the evolution of the carbohydrate- and vitamin-rich storage root in cultivated sweet potato. Root characteristics and genetic variation are poorly known for wild relatives of sweet potato and this project will provide a greatly improved understanding of the potential of wild relatives for sweet potato breeding programs. The project will train one graduate student and several undergraduates in laboratory techniques. Results from the research will be integrated within new teaching materials for middle school, high school and undergraduate students that emphasize the domestication process and importance of diversity in crop breeding programs.This research will characterize the timing of whole genome duplication events within sweet potato (Ipomoea batatas) and closely related species, and test whether these events are linked to the evolution of storage roots in the group. Numerous studies have implicated polyploidy as a major driving factor in the evolution of complex phenotypes; however, few studies have linked whole genome duplication events with the evolution of novel root traits. This study will apply modern phylogenomic methods to estimate relationships within the Ipomoea batatas complex and reconstruct the history of polyploidization and storage root development in the group. Genetic markers developed through gene capture and Restriction site Associated DNA Sequencing (RADSeq) technologies through this research will be useful for germplasm stock centers characterizing and preserving diversity within sweet potato and across the Ipomoea batatas complex. These findings will advance sweet potato breeding efforts, including recent work to develop productive and robust cultivars for Africa.

甘薯的根部富含碳水化合物和维生素，是许多国家人民的重要营养来源。目前提高甘薯产量的努力主要集中在少数育种品系上。作物物种的野生近缘种也可以成为作物改良遗传物质的重要来源，但甘薯与其野生近缘种之间的进化关系目前尚不清楚。该项目将利用基因组数据重建甘薯及其野生近缘种之间的进化关系，并揭示有助于栽培甘薯富含碳水化合物和维生素的贮藏根进化的遗传变化。对于甘薯野生近缘种的根部特征和遗传变异知之甚少，该项目将大大提高人们对甘薯野生近缘种育种计划潜力的了解。该项目将培训一名研究生和几名本科生的实验室技术。 研究结果将被纳入初中、高中和本科生的新教材中，强调作物育种计划中的驯化过程和多样性的重要性。这项研究将表征甘薯（Ipomoea batatas）和密切相关物种中全基因组复制事件的时间，并测试这些事件是否与该群体中贮藏根的进化有关。许多研究表明多倍体是复杂表型进化的主要驱动因素。然而，很少有研究将全基因组复制事件与新的根性状的进化联系起来。本研究将应用现代系统发育学方法来估计红薯复合体内的关系，并重建该群体的多倍体化和贮藏根发育的历史。本研究通过基因捕获和限制性位点相关 DNA 测序 (RADSeq) 技术开发的遗传标记将有助于种质资源中心表征和保存甘薯和红薯复合体的多样性。这些发现将推动甘薯育种工作，包括最近为非洲开发高产、健壮品种的工作。