镰刀菌酸对水稻稻瘟病菌和稻曲病菌的抑制作用

Research of the prevention of Fusaric Acid to Magnaporthe oryzae and Ustilaginoidea virens

摘要: 为研发新型农用杀菌剂的活性物质，采用菌丝生长速率法和孢子萌发抑制法，测定镰刀菌酸对水稻稻瘟病菌和稻曲病菌的抑制作用。结果表明，镰刀菌酸对水稻稻瘟病菌和稻曲病菌具有较强的抑菌活性，其对病菌菌丝生长的EC₅₀值分别为326.36、8.27 mg·L^-1，对孢子萌发的EC₅₀值分别为40.17、222.93 mg·L^-1。此外，盆栽试验发现，在水稻破口期和齐穗期喷施400 mg·L^-1镰刀菌酸，对稻瘟病的防治效果为66.72%；而在水稻破口前7 d喷施400 mg·L^-1镰刀菌酸，其对稻曲病的防治效果可达63.08%。

Abstract: In order to develop active substance of new fungicide, the prevention effect of fusaric acid to Magnaporthe oryzae and Ustilaginoidea virens were determined by mycelium growth rate methods and spore germination. The results indicated that fusaric acid had higher inhibition on M. oryzae and U. virens. The EC₅₀ value of fusaric acid to the mycelium growth of M. oryzae and U. virens were 326.36 and 8.27 mg·L^-1, and the EC₅₀ value on spore germination were 40.17 and 222.93 mg·L^-1. In addition, the pot experiments showed that the prevention control on M. oryzae was 66.72% with spraying fusaric acid (400 mg·L^-1) in the period of rice crevasse and full panicle, and the prevention control of fusaric acid (400 mg·L^-1) on U. virens was 63.08% with spraying in 7 days before the period of rice crevasse.