大豆抗疫霉根腐病基因Rps1-f和Rps10的精细定位和克隆

Phytophthora root and stem rot(PRR), caused by Phytophthora sojae, is one of the most destructive diseases of soybean. PRR can be effectively controlled by race-specific genes conferring resistance to P.sojae(Rps).However,the Rps genes are ususlly non-durable, as populations of P.sojae are highly diverse and quick to adapt, and can be overcome 8-15 years after deployment,it is thus important to identify novel Rps genes for development of resistant soybean cultivars. A F2 and F2:3 population was developed from a cross between resistant cultival PI567139B and the susceptibel cultivar Williams.Two novel Rps genes, Rps1-f and Rps10, were mapped to a 6.5cM interval on chr.3 and 3.0cM interval on chr.16. We plan to characterize the resistance of Rps1-f and Rps10 to predominant P.sojae races in China.And using a larger F3 residual heterozygosis lines (RHL) containing 15000 plants,we plan to fine map and cloning of candidate genes of Rps1-f and Rps10 using bioinformations and molecular biology techniques, develop functioanl markers based on two Rps genes,and functional study of the targeted genes by transgenic overexpression. This study will be useful to analyze the molecular mechanism of PRR resistance and provide useful genes and markers for soybean disease resistant breeding program.

由疫霉菌引起的根腐病是大豆生产上的毁灭性土传病害之一，挖掘和育种利用疫霉抗性（Resistance to Phytophthora sojae, Rps）基因是防治该病的有效途径。但由于疫霉菌新小种不断涌现，一些Rps基因已部分或完全丧失了抗性，目前我们面临有效抗源单一和抗性频临丧失的巨大风险。因此，新Rps基因的挖掘对抗病育种显得尤为重要和迫切。本实验室利用对疫霉菌广谱、高抗大豆品系PI567139B和感病品种Williams杂交获得的F2和F2:3群体，鉴定和初步定位了两个新Rps基因，Rps1-f和Rps10。本研究旨在评估这两个基因对我国疫霉病主要流行株系的抗性；利用已构建好的由15000个单株组成的F2:3残余杂合系进一步精细定位并克隆这两个基因；开发基于抗病基因的功能标记；通过转基因互补测验，验证基因的功能,并初步分析目的基因的抗病机制，最终为抗病育种提供可靠的基因和标记资源。

由疫霉菌引起的根腐病是大豆生产上的毁灭性病害之一，挖掘和利用疫霉抗性基于是防治该病的有效途径。本实验室前期利用对疫霉菌广谱、高抗大豆品系PI567139B和感病品种Williams杂交获得的F2和F2:3群体初步定位了两个新抗性基因RpsUN1和RpsUN2。本项目的研究内容是在初步定位基础上，通过筛选可利用的分子标记，结合重组个体的基因型和表型分析，精细定位RpsUN1和RpsUN2。本项目的主要结果如下：1）RpsUN1最终精细定位在3号染色体的150.8kb区间内，包含5个候选基因；RpsUN2最终精细定位在16号染色体的35.9kb区间内，包含4个候选基因；2）初步鉴定得到了RpsUN1和RpsUN2可能的候选基因；3）通过对19652份大豆品系聚类分析，795份大豆品系可能含RpsUN1,65份大豆品系可能含RpsUN2;4)PI567139B是唯一同时含有RpsUN1和RpsUN2的大豆品系。本项目的研究为大豆疫霉根腐病抗病育种提供了可靠的标记和基因资源。