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Sensitivity to azoxystrobin and kresoxim-methyl of 80 single-spore isolates of Magnaporthe oryzae was determined.The EC50 values for azoxystrobin and kresoxim-methyl in inhibiting mycelial growth of the 80 M.oryzae isolates were 0.006 ~ 0.056μg/mL and 0.024 ~ 0.287μg/mL, respectively.The EC50 values for azoxystrobin and kresoxim-methyl in inhibiting conidia germination of the M.oryzae populations were 0.004 ~ 0.051 μg/mL and 0.012 ~0.105μg/mL, respectively.There was significant difference of sensitivity to azoxystrobin or kresoxim-methyl between isolates respresenting differential sensitivity to carbendazim (MBC) and kitazin P (IBP), however, there was no correlation between this difference in sensitivity to azoxystrobin or kresoxim-methyl and sensitivity to MBC or IBP, indicating that there was no cross-resistance between azoxystrobin or kresoxim-methyl and MBC or IBP.In the protective and curative tests, kresoxim-methyl exhibited higher protective and curative control efficacy than azoxystrobin when applied at 150 and 250μg/mL accordingly, while azoxystrobin exhibited stronger inhibitory activity against M.oryzae isolates than that of kresoxim-methyl in the in vitro test.The results of field trials also showed that both azoxystrobin and kresoxim-methyl at 187.5g.a.i/hm2 provided over 73% control efficacy in 2010 and 2011 in both two sites, reepectively, exhibiting excellent activity against rice blast.Taken together, azoxystrobin and kresoxim-methyl should be good alternatives to MBC or IBP for the control of rice blast in China, but should be carefully used as they were both at risk fungicides.