STUDY ON THE STRAINS OF RICE BACTERIAL LEAF BLIGHT AND ITS APPLICATION IN FUJIAN

During 1980-1984, two hundred and ninetyeight strains of rice bacterial leaf blight(Xanthomonas campestris pv oryzae)were collected from 56 counties and were tested for pathogenicity in Fujian. According to the intensity of virulence, they were divided into four groups: I. II. III and IV, while 298 strains were inoculated onb differential varieties of rice. So far the reactions between pathogen and host showed that the quantitative differences were attended. No specificity was found. The tendency of strains distribution in Fujian showed that strong strains were in the coastal plains and weak strains were in the mountainous area. Some rice varieties. from home and abroad were tested for resistance by using 13 strains of II-IV groups. Fifteen varieties were showed higher resistance. In Fujian most of early and late rice varieties were susceptible or mid-resistance after tested, But the variety, 74-105, was higher resistant and durable to flooding in paddy fields than others. Therefore it was planted along river side where floods often took place. Weiyou No. 6,Weiyou No. 30,and Siyou No. 30 of hybrid rice were better resistant combinations which had been released in Fujian.