不同杀菌剂对水稻稻曲病菌的室内毒力及田间药效

Toxicity and Field Efficiency of Several Fungicides against Ustilaginoidea virens

采用生长速率法测定19种杀菌剂和苯醚甲环唑.井冈霉素A混配剂对水稻稻曲病菌的室内毒力,选择其中较好的8种药剂进行田间防效试验。结果表明:丙环唑、肟菌酯、咪鲜胺、戊唑醇、啶氧菌酯、嘧菌酯和苯醚甲环唑对稻曲病菌菌丝的抑制作用较强,EC50值分别为0.025 4、0.032 8、0.041 8、0.045 1、0.082 6、0.100 1和0.148 2mg.L-1;苯醚甲环唑和井冈霉素A按1∶2的比例混配增效作用非常明显,混剂共毒系数为174.78,EC50值为0.226 3mg.L-1;43%戊唑醇SC、25%嘧菌酯SC、25%咪鲜胺EC、8%井冈霉素A.4%苯醚甲环唑WP和25%丙环唑EC田间防效较好,分别为83.27%、82.76%、82.73%、80.66%和80.35%。

The toxicities of 19fungicides and the mixture difenoconazole validamycin A against Ustilaginoidea virens were tested in laboratory by detecting mycelial growth rate,and eight fungicides with better efficacy were selected to test in fields.The results showed that propiconazole,trifloxystrobin,prochloraz,tebuconazole,picoxystrobin,azoxystrobin and difenoconazole had stronger inhibition on mycelial growth,and the EC50values were 0.025 4,0.032 8,0.041 8,0.045 1,0.082 6,0.100 1and 0.148 2mg.L-1,respectively.The mixture of difenoconazole and validamycin A combined with the ratio of 1∶2had obvious efficiency on Ustilaginoidea virens,with the 174.78 and the EC500.226 3 mg.L-1.Field tests revealed that 43% tebuconazole SC,25% azoxystrobin SC,25% prochloraz EC,8% validamycin A 4%difenoconazole WP and 25% propiconazole EC had better control effect,which were 83.27%,82.76%,82.73%,80.66%and 80.35%,respectively.