滇蔗茅对甘蔗褐锈病的抗性遗传规律分析及抗性基因定位

Brown rust caused by Puccina melanocephala H. Sydow & P. Sydow is an important sugarcane disease, which seriously threatens the sugarcane production in our country. Selective breeding and planting resistant cultivars is the most economic and effective measure to control this disease. Exploration and utilization of resistant germplasm resources is a basis and a key to the resistance breeding. Erianthus rockii Keng is our country’s precious wild Saccharum related genera, the previous study of our team discovered it possess highly sugarcane brown rust resistance characteristics, and the molecular marker analysis results showed that the known brown rust resistance gene Bru1 was not detected in E. rockii cv., so it predicts E. rockii cv. may carry the new resistance gene. In this project, based on the previous working, E.rockii will be used as research object. The prepared reliable progeny populations derived from crosses between highly resistant E.rockii cv. and highly susceptible cultivar and self-bred progenies of highly resistant E.rockii cv. will be used to do the phenotypic identification for analysis the inheritance law of brown rust resistance gene in E.rockii cv.; the bulked segregant analysis and SSR marker will be performed to gene mapping of resistance to brown rust in E.rockii, construct the linkage map, and develop the molecular markers which can be used in marker-assisted selection for sugarcane brown rust resistance breeding. These results will provide the elite resistance resources for the effectively development of sugarcane brown rust resistance breeding, and lay the foundation to further develop on the molecular marker-assisted selection and the isolation and cloning of brown rust resistance new gene.

甘蔗褐锈病是由黑顶柄锈菌引起的一种重要病害，严重威胁着我国甘蔗生产。选育和种植抗病品种是防治该病最经济有效的措施。而抗病种质资源的发掘和利用是抗病育种的基础和关键。滇蔗茅是我国独有的甘蔗近缘属珍稀野生种，项目组前期研究发现其具有高抗褐锈病特性，经分子标记检测分析未检测到已发现的褐锈病抗性基因Bru1，预示滇蔗茅可能含有新的抗病基因。本项目拟在前期工作基础上，以滇蔗茅为研究对象，利用前期准备好的高抗褐锈病滇蔗茅与高感褐锈病栽培品种杂交获得的真实性后代群体及自交获得的后代群体，通过表型鉴定分析阐明滇蔗茅抗褐锈病的遗传规律；采用混合群体分离法及SSR标记定位滇蔗茅抗褐锈病的基因并构建连锁图谱，开发适合于分子标记辅助选择甘蔗抗褐锈病育种的分子标记。研究研究结果可为有效开展甘蔗抗褐锈病育种提供优良抗源材料，同时为进一步开展分子标记辅助选择育种及抗褐锈病新基因分离克隆奠定基础。

甘蔗褐锈病是由黑顶柄锈菌引起的一种重要病害，严重威胁着我国甘蔗生产。选育和种植抗病品种是防治该病最经济有效的措施，而抗病种质资源的发掘和利用是抗病育种的基础和关键。滇蔗茅是我国独有的具有高抗褐锈病特性的甘蔗近缘属珍稀野生种。本项目以滇蔗茅为研究对象，通过对高抗褐锈病滇蔗茅与高感褐锈病栽培品种杂交真实性后代F1群体及滇蔗茅自交后代群体进行抗性表型鉴定，研究明确了滇蔗茅对甘蔗褐锈病的抗性由1对新的显性单基因控制；构建了滇蔗茅抗褐锈病新基因定位的遗传分离群体，采集群体极端单株DNA构建抗、感池，通过采用混合群体分离法（BSA）及SSR标记，筛选出了2个与抗褐锈病基因连锁的SSR标记，为下一步滇蔗茅抗锈病基因的准确定位和分子标记辅助选择抗病育种打下了基础；创制了其它2个“高感×高抗”甘蔗种质杂交群体，明确了高抗种质的抗褐锈病遗传规律；采用混合群体分离法（ BSA）及SSR标记，筛选出了4个在抗、感亲本及抗、感池间有多态性的SSR标记，初步判定这4个SSR标记在染色体上的位点可能与抗褐锈病新基因存在连锁关系；检测分析了中国近年育成的甘蔗新品种及蔗区主栽品种对褐锈病的抗性及抗性基因，为筛选抗褐锈病优良新品种供生产上推广应用提供了依据。项目执行期间发表相关研究论文6篇，其中SCI论文4篇、国内1级核心刊物2篇；获国家发明专利1项，申报国际专利1项；制定颁布地方标准1项。