抗白粉病基因PmCH1357相关分子标记验证与评价

由禾本科布氏白粉菌Blumeria graminis(DC.) f. sp.tritici(Bgt)引起的白粉病是影响小麦产量和品质的一种主要病害。为了评价小麦抗白粉病基因相关分子标记在育种中的有效性与实用性,本试验利用感白粉病品种晋麦66和小偃麦衍生品系CH1357构建的341个F_(2:3)家系为材料,利用本课题组前期已定位的8个与抗白粉病基因 PmCH1357相关的分子标记(Xcfd81、Xbwm20、Xbwm21、Xbwm25、Xmp510、Xbwm8、Xbwm9和Xgwm190)对群体进行PCR检测,并接种白粉菌株E09进行苗期抗病性鉴定,分析PCR扩增产物与白粉病抗性间的相关性。结果表明,4个标记(Xcfd81、Xbwm20、Xbwm21和Xbwm25)对群体检测的纯合抗病基因型与纯合抗病表现型符合率均达到93%以上,可用于抗白粉病基因 PmCH1357的筛选;为进一步提高标记筛选的准确性,可使用多个标记组合,使用基因同一侧的标记组合进行选择会降低选择效率,使用基因两侧标记组合进行选择可有效提高选择的准确性。使用标记组合Xcfd81+Xbwm8对抗白粉病基因 PmCH1357进行选择可以获得更高的准确性及更多有效植株。

Evaluation and Validation of Molecular Markers Associated with Powdery Mildew Resistance Gene PmCH1357

Powdery mildew,caused by Blumeria graminis(DC.) f. sp. tritici(Bgt),is a serious wheat disease affecting yield and quality of wheat. In order to evaluate the effectiveness and practicability of the molecular markers associated with powdery mildew resistance in wheat,powdery mildew reactions to the Bgt isolates were evaluated at the seedling stage by inoculating E09 on 341 F_2:3 lines,derived from a cross between susceptible cultivar Jinmai 66 and Thinopyrum ponticum-derived wheat line CH1357. Eight molecular markers(Xcfd81,Xbwm20,Xbwm21,Xbwm25,Xmp510,Xbwm8,Xbwm9 and Xgwm190) associated with powdery mildew resistance gene PmCH1357 were applied to analyze the correlations between the PCR amplification products and the resistance to powdery mildew. The results indicated that the selection efficiency of the four molecular markers(Xcfd81,Xbwm20,Xbwm21 and Xbwm25) was more than 93%,which can be used for the screening of the powdery mildew resistance gene PmCH1357. Moreover,multiple marker combinations can further improve the accuracy of marker-assisted selection. The selection efficiency can be reduced when selected markers are on the same side of the gene,except that the selection efficiency can be significantly improved. Therefore,the combination of Xcfd81 and Xbwm8 with higher selection efficiency can be used to screen the powdery mildew resistance gene PmCH1357 and more effective lines can be obtained.