水稻抗稻瘟病基因Pi-ta的分子标记辅助选择

Molecular Markers assisted Selection of the Rice Blast Resistance Gene Pi ta

利用已建立的水稻抗稻瘟病基因Pi ta显性分子标记对 30个品系和 1 57个来自不同国家的一些水稻品种进行分子鉴定 ,并采用稻瘟病菌菌株ZN57(IC 1 7)和ZN6 1 (IB 4 9)人工接种试验进行致病性测试。结果表明 ,大部分品系和少数水稻品种含抗病基因Pi ta ,且对稻瘟病菌菌株ZN57和ZN6 1表现抗病反应。除此之外 ,利用两对显性分子标记YL1 55 YL87和YL1 83 YL87对 350个杂交F3代株系进行早期筛选 ,得到 1 1 8个抗病基因Pi ta纯合的株系。这些株系田间抗性调查结果表明 ,抗病基因存在与否与田间抗性相吻合。因Pi ta基因与许多其他抗病基因紧密连锁 ,而使含有Pi ta基因的品种具有广谱抗性 ,由此确立了Pi ta基因显性分子标记在育种辅助选择中的应用价值。

The dominant molecular markers of the rice blast resistance gene Pi ta were used to identify the presence in the Pi ta gene of 30 breeding lines and 157 rice cultivars coming from some different countries Meanwhile pathogenicity assays were performed with the rice blast fungus strains ZN57(IC 17) and ZN61(IB 49) The results indicated that most breeding lines and several rice cultivars contained the Pi ta gene and were resistant to strains ZN57 and ZN61 In addition,two pairs of dominant markers YL155/YL87 and YL183/YL87 were used to screen the resistant breeding lines at the early stage One hundred and eighteen lines containing homozygous Pi ta gene were isolated from 350 F 3 breeding lines At the same time,the rice blast resistances of these lines in the field were investigated The results demonstrated that the Pi ta presence consisted with the resistance in the field Considering that Pi ta is closely linked with other blast resistance genes,the Pi ta gene markers is very useful for marker assisted selection