报道了用基因标签法克隆水稻白叶枯病菌无毒基因的研究过程。通过接合实验，将Ｔｎ５引入水稻白叶枯病菌日本系统５号小种中去，在ＬＢ＋Ｋｍ平板上筛选了２５００个接合子；用剪叶接种法，将接合子接种水稻品种ＩＲ２６，得到了４个无毒基因突变体，分别用粘粒载体ｐＳａ７４７和质粒载体ｐＵＣ１９构建了ＪＸＯＶ核基因文库和无毒基因探针，采用菌落原位杂交法在基因库中钓取了１３个无毒基因克隆。该无毒基因片断在此病原的不同小种中均有同源性。 Reported the use of gene-tagging cloning non-toxic genes of rice bacterial blight pathogen research process. T25 was introduced into the japonica rice cultivar No.5 of Japan, and 2500 clones were screened on the LB + Km plate by splicing experiment. The cloned seeds were inoculated with IR26 by the method of leaf pruning, and 4 Non-toxic gene mutants were used to construct JXOV nuclear gene library and non-toxic gene probe respectively using cosmid vector pSa747 and plasmid vector pUC19, and 13 non-toxic gene clones were obtained by colony in situ hybridization. The non-toxic gene fragments in this pathogen in different races have homology.