Utilization Situation and Prospect of Gene xa5 AgainstPathotype V of Rice Bacterial Blight

In recent years, the strong virulence pathotypeⅤof rice bacterial blight grew up quickly in Southern China, which has become a major population and spread to the rice regions of Jiangsu and Zhejiang provinces in Southern China. Since pathotypeⅤcaused serious bacterial blight disease in rice production regions, it is urgent to breed and promote resistant varieties against pathotypeⅤ. The most economic and effective measure to control rice bacterial blight is to breed resistant cultivars for widely planting by using resistance genes. The Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, and Agricultural Science Research Institute of Panyu District of Guangzhou used IRBB5 carrying the recessive xa5 gene from IRRI that resists pathotypeⅤto breed resistant varieties with rice blast resistance source, hybridization, multiple cross, pedigree selection and synchronous resistance evaluation. We successfully bred serials of new rice resistance varieties such as Baixiangzhan, Baigengzhan and Baisizhan, which showed resistance to bacterial blight strongvirulence pathotypeⅤ(scales 1-3), resistance to rice blast (mediate to high resistance), good grain quality (scale 3 of rice quality of Guangdong), and equivalent production with major cultivars (compared with region trial control cultivars of Guangdong). These new resistant varieties were promoted and planted in the strong virulence pathotypeⅤregion along the west coast of Guangdong, which showed favorable superiority and wide application prospect in controlling rice bacterial blight with resistance varieties.