小麦抗条锈病基因Yr69连锁标记在育种中的应用评价

Evaluation on the Application of Molecular Markers Linked with the Wheat Stripe Rust Resistance Gene Yr69 in Wheat Breeding

由条形柄锈菌小麦专化型(Puccinia striiformis West.f.sp.tritici Eriks.,Pst)引起的小麦条锈病是严重威胁小麦生产的重大病害之一。为促进抗条锈病基因Yr69在小麦育种中的应用,利用8个与Yr69连锁的分子标记对推广品种长4738与Yr69的载体品系CH7086构建的F2群体为材料进行检测,利用小麦条锈菌CYR32、CYR33、CYR34混合小种(1∶1∶1)接种F2:3家系进行抗病性鉴定,并评价Yr69连锁标记在育种中应用的有效性。结果表明,4个共显性标记Xgwm636、Xgwm210、Xwmc382和X2AS33对Yr69具有较好的检测效果,其检测准确率随着分子标记与目标基因遗传距离的减小而提高。其中,X2AS33的检测准确率高达96.7%,是分子辅助育种中检测Yr69的较理想连锁标记。

Wheat stripe rust caused by Puccinia striiformis West.f.sp.triticiEriks.(Pst)is one of the major diseases seriously threatening wheat production.To promote the application of the wheat stripe rust resistance gene Yr69 in wheat breeding,eight molecular markers linked with Yr69 were used to detect the presence of Yr69 among the F2 progeny constructed from a cross between wheat cultivars Chang 4738 and CH7086(Yr69).The resistance of the F2:3 family lines to wheat stripe rust were identified with the mixture of Pst races CYR32,CYR33 and CYR34(1∶1∶1).The results showed that four co-dominant markers Xgwm636,Xgwm210,Xwmc382 and X2AS33 had better detection accuracy for the wheat stripe rust resistance gene Yr69 and the detection accuracy increased as the decrease of genetic distance between the marker and the target gene.The detection accuracy of X2AS33 was up to 96.7%,which can be considered as an ideal molecular marker for identifying Yr69 in molecular marker-assisted selection breeding.