Toxicity Effect of 8 Fungicides Against Bipolaris maydis in Lab

The toxicity of 8 kinds of fungicides were measured against the Bipolaris maydis by Horafall and growth velocity in lab.And toxicity curve and corresponding EC50 values were obtained.The results indicated that Diniconazole is the cruelest to Bipolaria maydis in all tested fungicides.It's correlation coefficient of regression curve and EC50 was 0.883,1.8858E+1.Procymidone and Chlorothalonil was the second position and their correlation coefficient of regression curve and EC50 were 0.996,0.974 and(9.1643E)+1,9.2918E+1.Others are weakly to Bipolaris maydis.The toxicity of 3 combinations with different proportion were measured.The best combinations were that procymidone and diniconazole in 2:8,chlorothalonil and diniconazole in 6:4 and chlorothalonil and procymidone in 6:4.