小麦赤霉病抗性分子标记的筛选及其利用

Screening and application of molecular markers linked to wheat scab resistance

以4个来源不同的小麦赤霉病抗源为材料,筛选与赤霉病紧密连锁的抗性标记,并进行赤霉病抗性数量性状原点(QTL)定位。结果表明:4个来源不同的抗赤霉病品种所携带的主效抗性QTL均在染色体3BS上,尽管它们的抗性效应不相等,但位置相同,均在Xgwm533与Xgwm493之间。在此基础上,将筛选到的SSR抗性标记在抗感程度不同的品种和高代品系中进一步验证,寻找有效的赤霉病抗性连锁标记。结果表明,选用Xgwm533、Xgwm493或Xbarc133赤霉病抗性紧密连锁标记,在多基因聚合育种群体和回交育种群体中,单标记选择效率可达70%左右。由此可见,在传统育种基础上,运用分子标记辅助选择,进行小麦赤霉病抗性改良,可提高赤霉病抗性选育效果。

The experiments of screening markers tightly linked with wheat scab resistance and localization of quantity trait loci（QTLs） were conducted,based on 4 materials with different resources of wheat scab resistance.The results showed that the major QTL of the resistance in each variety located on the short arm of chromosome 3B,and lied between Xgwm533 and Xgwm493,although the control effect of QTL in each variety was not equal.The selected SSR markers were further verified in wheat varieties and their advanced lines with different levels of resistance.When using Xgwm533,Xgwm493 or Xbarc133 as tightly linked markers,the selection efficiency was high as about 70% in multi-gene pyramiding breeding populations and backcrossing breeding populations.Therefore,molecular marker-assisted selection（MAS） could improve the selection efficiency for enhancement of resistance to wheat scab,compared to traditional breeding techniques.