Identification and Genetic Analysis of Rice Blast Resistance of 5 Resistant Varieties

Rice blastresistant varieties,Dwarf Tetep,ChiKuaiai,Hongjiaozhan,Wunong N0. 1 and Gunong No. 13 were identified for their blast resistanec in 1990～1993.The resistant rates of these varieties to physiological races were 100.0%,72.73%,81 82%,8l.82%and 100.0%respective-ly,and to isolated strains were 96.01%,95.21%,94.52%,94.57%and 98.46%respective-ly。These 5 varieties were also undertaken the jiont identification in national and Fujian provincial uniform rice blast nursery.The results showed that,4 of them performed highly resistant to leaf and panicle blast,except Wunong No.1 which appeared middle resistant Genetic analysis showed that,the resistanec to physiological races ZA49,ZB1 and ZB13 of the varieties Dwarf Tetep,Chikuaiai and Wunong No.1 were governed by two pairs of dominant genes,while the variety Wunong No.1had only one dorninant gene of resistance to race ZC1.Segregation ratioes of three pairs of genes for the resistance to races ZB13 and ZC13 were detected in F2 populations of the crosses of Chikuaiai/Wunong No.1 and Chikuaiai/Gunong No.13,respectively.