小麦品种Grandin抗白粉病基因的鉴定和SSR标记

为了明确美国红粒硬质春小麦品种Grandin在小麦育种中的利用价值,对其进行了白粉病抗性基因的鉴定,并利用分子标记进行了定位.遗传分析结果表明,Grandin携带1个显性抗白粉病基因,该白粉病抗性基因与小麦SSR标记位点Xcfd81和Xcfd78连锁,遗传距离分别为0.9 cM和3.3 cM.根据小麦微卫星标记遗传连锁图以及利用中国春第5同源群双端体系对这两个SSR标记位点的定位结果,该抗白粉病基因被定位于小麦染色体5D短臂,与小麦已知抗白粉病基因Pm2的定位结果基本一致.进一步通过标记多态性比较和小麦白粉菌分小种鉴定证实Grandin所含的抗白粉病基因就是Pm2.同时还对Pm2基因的STS标记在不同群体中的实用性进行了讨论.

Identification and Tagging of the Wheat Powdery Mildew Resistance Gene in Wheat Cultivar Grandin

The red hard spring wheat cultivar Grandin introduced from the US was highly resistant to Blumeria graminis f. sp. tritici race No. 15 in China. Genetic analysis and SSR marker test were conducted in order to clarify the resistance gene in Grandin and to facilitate utilization of the cultivar Grandin in wheat breeding programs. Genetic analysis indicated that the resistance of Grandin was conferred by a sing Xcfd81 and Xcfd78 e dominant gene. The powdery mildew resistance gene was linked to two SSR loci with genetic distance 0.9 cM and 3.3 cM, respectively. Based on the wheat microsatellite map and physical location of these two SSR loci, the powdery mildew resistance gene in Grandin was mapped on the short arm of wheat chromosome 5D, the same location as the Pro2 gene of wheat. The powdery mildew resistance gene in Grandin was proved to be Pro2 by the comparison of polymorphic SSR amplicons between Grandin and Pro2 carrier and the gene postulation by multiple races inoculation to Grandin. The usefulness of the STS marker of Pro2 in various breeding popula- tions was also discussed.