湖北省水稻白叶枯病菌致病型分化检测与分析

Differential Detection and Analysis of Pathotypes of Xanthomonas oryzae pv. oryzae in Hubei Province

为了掌握湖北省水稻白叶枯病菌(Xanthomonas oryzae pv. oryzae)的致病型分化和变异动态,采集湖北省水稻种植区白叶枯病样品分离白叶枯病菌,用含不同白叶枯病抗性基因的近等单基因系IRBB2、IRBB3、IRBB5、IRBB13、IRBB14和IR24作为鉴别寄主,采用剪叶接种,根据寄主和分离菌株的互作反应检测病菌的致病型分化。鉴定结果表明,在湖北省水稻白叶枯病的致病型R9(SSSSSS)占鉴定菌株的46.2%,还有Unknown类型的菌株占38.5%。与前人研究结果相比,湖北白叶枯病菌致病型发生了很大的变异,主要致病型由R4变成了R9,且出现了以前没有的R8(SSRSSS)类型和Unknown类型。同时,鉴定了Xa7和Xa23介导的湖北省白叶枯病菌的抗性,Xa7有2个分离菌株可以克服其抗性,而Xa23能抗所有分离菌株,因此在湖北省可以利用这2个基因进行水稻抗白叶枯病育种。

In order to understand the pathogenic differentiation and variation of Xanthomonas oryzae pv.oryzae in Hubei province,pathogenic isolates were collected from rice growing areas in Hubei province.Near isogenic lines IRBB2,IRBB3,IRBB5,IRBB13,IRBB14 and IR24 carrying different resistance genes were used to detect pathogenic differentiation.Leaf-clipping method was used to detect pathogenic differentiation of the pathogen according to the interaction between the host and the isolates.The results showed that the pathotype R9(SSSSSS)of rice bacterial blight was 46.2%,and the unknown strains were 38.5%.Compared with the results of previous studies,the pathotypes of bacterial blight in Hubei province had undergone considerable variations,and the main pathogenic form was changed from R4 to R9,with the emergence of R8(SSRSSS)types which wasn’t detected and unknown types.At the same time,Xa7 and Xa23 mediated resistance were identified.A few strains of Xa7 gene could be overcome,while Xa23 could resist all strains.Therefore,these two genes could be used in rice breeding for resistance to bacterial blight in Hubei province.