Toxicity Test of Different Fungicides Against the Pathogen of Corn Stalk Rot

The study aimed to acquire the high efficiency fungicides of corn stalk rot. The inhibitory activities of20 fungicides on Pythium inflatum and Fusarium graminearum were tested in the mycelium growth rate method.The propineb,metalaxyl-mancozeb,dimethomorph and fluopicolide had high toxicity to Pythium inflatum and the EC50 was 0. 40 μg / m L,0. 47 μg / m L,0. 61 μg / m L and 2. 64 μg / m L,respectively. Fusarium graminearum had high sensitivity to fludioxonil,tebuconazole and carbendazim,and the EC50 was 0. 06 μg / m L,0. 32 μg / m L and 0. 85 μg / m L,respectively. However,the inhibitory activity of difenoconazole and myclobutanil to Fusarium graminearum was lower than the above three fungicides,and the EC50 was 1. 71 μg / m L and 1. 80 μg / m L. The field experiments can be conducted on the 9 fungicides that had high antimicrobial activity to the tested pathogens. Furthermore,in order to control the corn stalk rot effectively,the high efficiency mixtures that could eliminate the disease would be prepared for single infection or mixed infection of Pythium inflatum and Fusarium graminearum.