The toxicity of 6 fungicides against Phytophthora parasitica was detected by the method of mycelium growth inhibition. The results showed that 20% flumorph WP had the best control effect. The followed fungicides were 50% boscalid WG and 100 g/L Cyazofamid SC; Butwith the increase of dosage,the control effect of 50% Azoxystrobin WG did not increase significantly, however its EC50 was low. The control effect of 40% chlorothalonil SC and 722 g / L propamocarb hydrochloride aqueous solution were low, with weak ...