12个小麦品种(系)白粉病抗性的遗传分析

利用17个不同来源和毒力的白粉菌菌株对12个小麦品种(系)进行苗期抗性鉴定和抗病性遗传分析，同时利用Pm2和Pm8基因的特异分子标记检测了相应基因。供试的12个品种至少能够抗11个白粉菌菌株。用E09、E20和Bg2菌株接种F₂群体，抗感植株分离比例和适合性测验证明这12个品种对不同白粉菌菌株的抗性均受1对显性基因控制。抗谱分析和基因紧密连锁分子标记(Xcfd81)分析表明良星66很可能含有Pm2或其等位基因。ω-黑麦碱基因(1RS染色体)和Glu-B1基因(1BS染色体)特异分子标记分析结果证明，山农20和郑麦9962含有T1BL·1RS易位染色体，即可能携带Pm8基因。由于Pm8基因对大多数菌株表现感病，所以这2个品种除Pm8外，还具有其他抗病基因。偃展4110与天民668对参试菌株的反应型表现一致，其他材料对不同菌株的反应型表现不同。

Inheritance of Resistance to Powdery Mildew in 12 Wheat Varieties (Lines)

Wheat powdery mildew, caused by the biotrophic parasitic fungus Blumeria graminis (DC.) f. sp. tritici E.O. Speer. is one of the most epidemic diseases in many wheat (Triticum aestivum L.) producing regions in China and other parts of the world. The information on inheritance of resistance to powdery mildew in commercial wheat cultivars is important for controlling the disease and developing new resistant cultivars. In the present study, 17 isolates of B. graminis were used to postulate and analyze powdery mildew resistance genes in 12 wheat cultivars at seedling stage. Molecular detection was performed to disclose the presence of Pm2 and Pm8 for powdery mildew resistance. All of the 12 wheat cultivars were resistant to at least 11 tested isolates. Isolates E09, E20, and Bg2 were used to test F₂ populations for analyzing inheritance of powdery mildew resistance in these wheat cultivars. The results demonstrated that single dominant gene(s) was responsible for powdery mildew resistance in these cultivars. The reactions to different isolates of B. graminis and analysis of amplification with Pm2-linked marker Xcfd81showed that Pm2 or its allele was most likely present in Liangxing 66. Using ω-secalin gene- and Glu-B1 gene-specific markers on chromosome arms 1RS and 1BS, respectively, the presence of T1BL·1RS translocation chromosome carrying Pm8 was detected in Shannong 20 and Zhengmai 9962. Since Pm8 was not effective against most isolates tested in this study, other unknown genes for powdery mildew resistance could be present in Shannong 20 and Zhengmai 9962 in addition to Pm8. The reaction patterns of Yanzhan 4110 and Tianmin 668 were identical. The remaining cultivars developed different patterns of reaction to the B. graminis isolates tested.