Abstract:In order to know virulence of Magnaporthe grisea Barr. from rice in Fujian Province of China, pathogenicity of 87 M.grisea single spore isolates from 5 rice growing regions of Mindong, Minnan, Minxi, Minbei and Minzhong during 2003 to 2006 in Fujian Province was studied against 41 rice varieties known resistance genes. The results indicated that all the avirulence genes, which corresponding to the resistance genes, were detected in Fujian isolates, 66.67% of isolates had stronger pathogenicity. The virulence frequency of the isolates group to resistance gene Pi-d2, Pi- k (1), Pi-km, Pi-kh, Pi-1 (1), Pi-z5 (1), Pi-z5(2) and Pi-1(2) was all below 10%, which suggested that these resistance gene could be used as resistance resources in rice breeding in Fujian Province. 40, 37, 36 and 38 avirulence genes were detected in isolates from 2003 to 2006 respectively, 34 avirulence genes were detected in each year, and 30 avirulence genes were detected in all five rice growing regions, avirulence genes Avr-a (2), Avr-3(2), Avr-ks, Avr-4b, Avr-b, Avr-kp (C), Avr-km(C), Avr-ta (C), Avr-11 (C), Avr-19 (t), Avr-t and Avr-a(1) occurred at a frequency of below 30%, it suggested that resistance genes corresponding to these avirulence genes would not be suitable to apply in rice breeding of resistance for control of M.grisea in Fujian Province. Most of isolates contained 17, 14, 23, 18, 16 avirulence genes with combination fre- quencies of 13.79%, 10.34%, 9.20%, 8.05% and 8.05% respectively.