Abstract: The international differential system for resistance to bacterial blight(BB) was established using a common base of research methods by collaborative studies between Tropical Agricultural Research Center(TARC) and International Rice Research Institute(IRRI) in 1982-1987.Up to June 2005,there are a total of 30 BB resistance genes registered internationally or reported in international journals.Among them,the genes Xa22(t),Xa26(t),xa26(t),Xa27(t),Xa28(t),Xa29(t) and three Xa25(t) were tentatively designated and subjected to further be re-arranged.Twenty-one and 9 out of the 30 Xa genes are dominant and recessive,respectively.Thirteen genes exhibit all-growth-stage resistance,two genes Xa21 and Xa25(t)(O.minuta) express resistance at the later tillering stage,and the other 15 genes confer only adult-stage resistance.Seventeen Xa genes were mapped,including Xa3,Xa4,Xa10,Xa21,Xa22(t),Xa23,and Xa26 on chromosome 11; Xa1,Xa2,Xa12,and Xa14 on chromosome 4;xa5 and xa13 on chromosome 5;Xa7 and Xa27(t) on chromosome 6;Xa25(t) on chromosome 12;and Xa29(t) on chromosome 1.Five Xa genes were cloned,including Xa1,xa5,Xa21,Xa26 and Xa27.Application of resistance to bacterial blight was also discussed.

Key words: rice, bacterial blight, resistance, gene identification

摘要： 1982~1987年，日本热带农业研究中心（TARC）和国际水稻研究所（IRRI）合作采取统一研究方案，创建了国际水稻白叶枯病抗性鉴别系统。统一了命名，删去了重复（包括与Xa3相同的Xa4b、Xa6和xa9）。截至2005年6月，经国际注册确认和期刊报道的水稻白叶枯病抗性基因共30个，其中 Xa22(t)、Xa26(t)、xa26(t)、Xa27(t)、xa28(t)、Xa29(t)和3个Xa25(t)为暂定名基因，有待订正。在30个基因中，21个为显性基因（Xa），9个为隐性基因（xa）；13个表现全生育期抗性，15个为成株期抗性，Xa21和Xa25(t) (O. minuta)两个基因在分蘖后期表达抗性。已被定位的抗性基因有17个，即第11染色体上有7个，Xa3、Xa4、Xa10、Xa21、Xa22(t)、Xa23和Xa26；第4染色体上有4个，Xa1、Xa2、Xa12和Xa14;第5染色体上有2个，xa5和xa13；第6染色体上有Xa7和Xa27；第12染色上有Xa25(t)；第1染色体上有Xa29（t）。包括Xa1、xa5、Xa21、Xa26五个基因已被克隆。并讨论了合理利用抗性基因等问题。

关键词: 水稻, 白叶枯病, 抗性, 基因鉴定