通过分子标记辅助选择技术选育携有水稻白叶枯病抗性基因Xa23的水稻株系

摘要

The rice bacterial blight resistance gene Xa23, which is carried by the donor parent 18113, was introduced into the intersubspecific restorer line H705 and good grain quality restorer line H706 by crossing and molecular marke-assisted selection(MAS). Seventy-one and 52 homozygous lines carrying Xa23 were obtained from the 18113/H705 F3 and 18113/H706 F3 lines, respectively by PCR with EST marker C189. The bacterial blight resistance of these lines was investigated with the pathotype Ⅳ representative strain Zhe 17.3 by clipping method. Sixty-one and 44 lines showed the bacterial blight resistance,with the MAS accuracies of 85.92％ and 84.61％, respectively. The C189 was one of the effective MAS markers for testing Xa23 gene. In addition, further research is needed to elucidate the mechanisms of higher false positive rate than theoretical exchange rate.%通过杂交和分子标记辅助选择技术,将亲本材料18113携有的水稻白叶枯病抗病基因Xa23导入亚种间恢复系H705和优质恢复系H706.利用EST标记C189检测目的基因,在18113/H705 F<,3>和18113/H706 F<,3>株系中,分别获得71和52份携有Xa23纯合基因型恢复系.采用水稻白叶枯病Ⅳ型小种代表菌株浙173进行剪叶接种,分别鉴定出61和44份抗病株系,它们的分子标记辅助选择准确率分别为85.92%和84.61%.研究结果表明,C189是检测Xa23基因的有效分子标记之一,不过,其假阳忭的几率高于理论交换率的现象还有待于进一步研究.