Antifungal Activity and Toxicity of Two New types of Polyene Antibiotics against Four Species of Rice Pathogenic Fungi

The antifungal activity and toxicity of new type polyene macrolide antibiotics-Antifungalmycin 702 and Fungichromin against Rhizoctonia solani, Hel- minthosporium sigmoideum Car. , Magnaporthe grisea and Ustilaginoidea virens were studied by mycelial growth rate method and mycelial dry weight method in vitro. The results showed that both of Antifungalmycin 702 and Fungichromin had strong antifungal activity against four speices of rice pathogenic fungi. Treated with 50 μmL Antifungalmycin 702 , the inhibitory rates of Antifungalmycin 702 agmnst R. solani, H. sigmoideum Cav., M. grisea and U. virens were 100%, 100%,91.20% and 68.10%, and EC50 and ECho were 7.00, 10.30, 14.41, 26.71 and 13.20, 17.66, 27.67,128.28 p.g/mL, respectively. Treated with 13 pg/mL Fungichremln, the inhibitory rates of Fungichromin against four speices of rice pathogenic fungi were 78.20%, 100%, 100% and 79.17%, and ECs0 and ECg0 were 1.47, 1.91, 2.37, 0. 20 and 41. （15, 3.92, 4.34, 135.54 gg/mL, respectively. The antifungal activity of Fungichromin was stronger than Antifungalmycin 702.