欧洲小麦品种Mega抗条锈病基因的遗传分析及分子标记

Genetic analysis and molecular mapping of stripe rust resistance gene in European wheat cultivar Mega

本研究表明欧洲小麦品种Mega对我国小麦条锈病重要流行小种CYR30、CYR31、CYR32、Su-4和Su-14在苗期都具有良好的抗病性。采用小麦条锈菌小种CYR30对Mega与感病小麦品种铭贤169杂交的F1、F2和BC1代及双亲进行苗期抗病性遗传分析,结果表明,Mega对CYR30的抗性由1对显性基因独立控制。采用SSR标记技术对其携带的抗性基因进行分子标记,在237对SSR引物中,发现位于5BL上的2个SSR引物位点Barc232、Wmc640在双亲和抗、感池间能扩增出稳定的特异性片段,与抗病基因连锁的遗传距离分别是3.7cM和8.6cM,暂命名为YrMe。本研究结果为科学利用Mega抗条锈基因培育抗病品种提供了依据。

Mega, one of the European wheat cultivar, possessed effective resistance to the dominant races（CYR30,CYR31,CYR32,Su-4 and Su-14） of Puccinia striiformis f . sp. tritici in China at seeding stage. To identify and map new stripe rust resistance genes, seedlings of the parents, F1, F2, BC1 progeny derived from a cross between resistant cultivar Mega and susceptible cultivar Mingxian169 were tested with the race CYR30 of P. striiformis f. sp. tritici in greenhouse. Simple sequence repeat （SSR） techniques were used to develop molecular markers linked to the resistance gene in wheat cultivar Mega. 237 pairs of wheat SSR primers were used to test the two parents, as well as resistant and susceptible bulks. Subsequently, 2 SSR markers were employed for genotyping the F2 population. The results indicated that the stripe rust resistance in cultivar Mega was conferred by a single dominant gene , temporarily designated as YrMe, located closely to the chromosome 5BL and flanked by two SSR markers Barc232 and Wmc640, with the genetic distances of 3.7 cM and 8.6 cM, respectively. The research provided theoretical basis to wheat breeding in the use of Mega.