水稻稻曲病有效药剂筛选及药效评价

Screening and Evaluation of Fungicides for Control of Rice False Smut Caused by Ustilaginoidea virens

通过对水稻稻曲病进行室内毒力测定与田间药效试验,筛选出防治效果较好的杀菌剂。采用菌丝生长速率法测定9种杀菌剂对水稻稻曲病菌的室内毒力,并进行7种杀菌剂的田间药效试验。氟环唑、吡唑醚菌酯、丙硫菌唑、嘧菌酯、丙环唑、咪鲜胺、戊唑醇的EC50值小于0.20μg/mL,抑菌效果较好。田间药效试验中,430 g/L戊唑醇SC 96.75 g a.i./hm^(2)、125 g/L氟环唑SC 84.4 g a.i./hm^(2)、250 g/L嘧菌酯SC 225.0 g a.i./hm^(2)的防效最好,防效分别为83.59%、82.77%、81.13%。戊唑醇、氟环唑和嘧菌酯对水稻稻曲病具有良好的防效,可作为该病的有效防治药剂。

The study aims to screen out effective fungicides against rice false smut (caused by Ustilaginoidea virens) by indoor toxicity determination and field efficacy trial.Indoor toxicities of 9 fungicides against U.viren were tested by using mycelium growth rate method,and the control effects of 7 fungicides on rice false smut were detect in field trials.Indoor toxicity data revealed that epoxiconazole,pyraclostrobin,prothioconazole,azoxystrobin,propiconazole,prochloraz and tebuconazole had obvious inhibitory effect with EC50value of less than 0.20μg/m L.Field trial results demonstrated that 430 g/L tebuconazole SC of 96.75 g a.i./hm^(2),125 g/L epoxiconazole SC of 84.4 g a.i./hm^(2),250 g/L azoxystrobin SC of 225.0 g a.i./hm^(2)had excellent control effect of83.59%,82.77%,81.13%,respectively.Therefore,tebuconazole,epoxiconazole and azoxystrobin are ideal fungicides for controlling rice false smut,and could be recommended to application in field.