Research Progress on Populations and Physiological Race Distribution of Rice Blast Pathogen(Magnaporthe grisea) in China

Magnaporthe grisea population distribution and the physiological race composition in major rice growing regions in China are summarized.Physiological races of M.grisea ZF,ZD,ZE and ZA were the dominant populations in Northeast China rice growing regions,with the occurring frequencies of 23.2%,22.2%,15.6% and 12.3%,respectively.High pathogenicity virulent populations of ZA and ZB are the major strains in Southwest China rice-producing regions,the occurrence frequency of ZB and ZA reached 53% and 22.3% in Sichuan Province.In Guizhou Province,the races of ZB,ZA and ZG were the dominant populations with occurrence frequency of 41.4%,18.5% and 10.7%,respectively.ZB and ZC were the major populations in south China's rice growing areas with the occurrence frequency 28.0% and 37.0%.Weak virulence races of ZE,ZF and ZG were the major populations in North China rice growing regions with the occurrence frequency of 21.5%,22.1% and 44.3%.Races of ZB,ZG,ZC and ZA were the dominant populations in East China rice planting areas with the occurrence frequency of 43.3%,25.0%,13.9% and 12.3%,respectively.The major populations in central China were ZA,ZB,ZE and ZC,with the occurrence frequency of 34.9%,28.8%,21.4% and 14.1%,respectively.Few rice were planted in northwest China,however,the strong pathogenicity races of ZA and ZB were dominant populations.