Objective  The pathogenicity and avirulent genotypes of Magnaporthe oryzae found in Fujian in recent years were analyzed to define their existence and year-to-year changes in different regions.

  Method  For the study, 179 strains of rice ear neck blast were collected from 9 major rice-producing areas in the province from 2018 to 2020 and isolated to identify the near-isogenic lines (NILs) that contained only one resistance gene.

  Result  Among the 179 rice blast strains, the proportion of strong, slightly strong, medium, and weak pathogenic classes were 26.81%, 36.31%, 27.37%, and 9.51%, respectively. Among the 4 high resistance genes, Pi-z⁵ and Pi-9(t) showed the greatest resistance frequencies of 91.49% and 91.25%, respectively, followed by Pi-k^h and Pi-1 of more than 80%. During the sampling years, the 9 avirulent genes produced more than 20% on frequency decline were Avr-k^h, Avr-7(t), Avr-5(t), Avr-3, Avr-k^p, Avr-19(t), Avr-k^m, Avr-z, and Avr-k^s. In the 23 types of avirulent genes, the pathogens with 6, 7, 8, 9, and 11 gene combinations had the highest appearance frequencies of 10.06%, 8.94%, 8.94%, 7.82%, and 8.38%, respectively. A total of 24 avirulent genes were identified in the rice blast strains found in the 9 regions that showed the highest frequencies of appearance at 49.19% in Shanghang, 48.18% in Guangze, and 41.23% in Wuyishan.

  Conclusion  Most rice blast strains in Fujian were strongly pathogenic to the 24 resistance genes, as discovered by this study. Among all, Pi-z⁵, Pi-9(t), Pi-k^h, and Pi-1 had the greatest frequencies of resistance, Avr-z⁵ and Avr-9(t) the most consistent over the years, and Avr-k^s, Avr-b, and Avr-ta the lowest with a frequency less than 20%. The corresponding avirulent genes could be useful for breeding, but the selection must be done with due caution.