中文摘要：

根据广谱抗瘟基因Pigm精细定位结果，筛选获得共显性InDel标记DG-3在P塘m基因供体亲本谷梅4号与9个籼稻受体亲本之间存在明显且稳定的多态性。在T98B×谷梅4号和R640×谷梅4号2个组合的BC1F1群体中随机取单株进行稻瘟病抗性表型及基因型分析，结果表明，无论是田间病圃鉴定，还是室内接种鉴定，分子标记DG-3对这2个组合回交群体的抗稻瘟病表型选择效率达95％以上，说明DG-3与Pigm基因紧密连锁。在此基础上，采用分子标记辅助选择与回交育种相结合的方法，利用DG-3在9个组合的回交群体中选择含有目的基因的单株分别与相应轮回亲本逐代回交，分别获得了9个组合的Bc3F1群体，为进一步连续回交定向改良轮回亲本的稻瘟病抗性奠定了基础。

英文摘要：

The broad-spectrum rice blast resistance gene Pigm was identified in a Chinese local rice cuhivar Gumei 4 and finely mapped at the Pi2/9 locus of Chromosome 6, and a Pigm-tightly-linked and polymorphic codominant InDel marker, DG-3, was developed and employed for improving the blast resistance of nine receptor indica rice lines by marker-assisted selection in this study. The phenotypic selection accuracy of blast resistance by DG-3 was above 95% for randomly sampled individuals of two BCIF1 populations, T98B × Gumei 4 and 11640 × Gumei 4, ac- cording to the genotypic and phenotypic coparative analyses both in field nursery and indoor inoculation assays. The BC3FI populations of nine crosses were developed based on the DG-3 genotypic selection, which paved a way for improving blast resistance of these receptor rice lines through further backcross breeding.