三个小麦赤霉病抗源的抗性QTL定位

为寻找小麦赤霉病抗性基因及可用于分子标记辅助育种的抗性连锁标记．对中国的三个小麦赤霉病抗源苏麦3号、望水白和宁894037进行了抗性QTL的定位研究。SSR、AFLP分析与QTL分析结果表明，尽管三个抗源的来源和遗传背景并不同，但均在3B染色体短臂上发现抗性主效QTL，不同遗传群体所获得的QTL位点所处的染色体区段略有差异，位于QTL两翼的SSR标记也有所不同。苏麦3号的赤霉病抗性主效QTL位于3B染色体上的标记区间Xgwm533～Xgwm493内；宁894037的抗性位点分布于3B和6B染色体上。分别定位于标记Xgwm493～Xbarcl33和Xgwm644-Xgwm518之间；望水白的抗性主效QTL也位于3B染色体上．定位于标记Xgwm493～Xbarc147之间。微效QTL由于遗传群体的不同，分别住于1B、3B和2A染色体上。研究还表明，寻找抗性QTL在3B染色体以外的新抗源十分必要。

QTL Location of the Fusarium Head Blight Resistant Gene in Three Wheat Varieties

To identify the resistance gene to Fusarium head blight (FHB) and employ molecular markers associated with the resistant gene for marker-assisted selection, quantitative traits loci (QTL) of FHB resistance in three wheat resistant sources of Sumai 3, Wangshuibai and Ning 894037 had been characterized with random amplified polymorphic DNA (RAPD), simple sequence repeats (SSR) and amplified fragment length polymorphism (AFLP) markers. Despite their different genetic backgrounds, a major QTL was detected on short arm of chromosome 3B with appreciable difference of the marker interval in all three varieties. In Sumai 3, the major QTL on 3B chromosome located in the interval of two SSR markers Xgwm493~Xgwm533.In Ning 894037,there were two QTLs on chromosome 3B and 6B, flanked by markers Xgwm493/Xbarc133 and Xgwm644~Xgwm518, respectively. Wangshuibai also carries the major QTL in the interval of markers Xgwm493~Xbarc147. The present results indicate that further attempts are still needed to explore new resistance source with different QTL.