Abstract:Differential breeds were collected in 4 counties(or divisions) in Qianjiang rice region during 1996-2000 and 203 single conidia isolates are obtained.The isolates were assessed on 7 Chinese differential varieties,and 6 groups and 39 races were identified.Among them,grou PZB were the predominant races with 66.50% of isolated frequency,ZA13 is the frequency of 7.88%,ZB1.5.13.15.16.32 are the frequency of 5.91%,4.43%,20.69%,7.88% and 4.43%.They are all important races.38 races are detected that show grou PZB are 86.84% in all races.