Efficacy of Chlorpyrifos 5% GR against Bradysia odoriphaga

[Aims]The effect of chlorpyrifos 5% GR on Bradysia odoriphaga was investigated in this study.The control efficiency,optimal dosages and persistence were determined by field trial.[Methods] The field trial was carried out using the randomized block design,and the significance of difference was performed by Duncan's multiple range test(DMRT).[Results] At the concentration of 1875 g a.i./ha,chlorpyrifos 5% GR showed good control efficiency against Bradysia odoriphaga with control of 87.07 and 84.62% after 21 days after treatment in 2010 and 2011,respectively,and insect population control effect are 90.22 and 89.83%,respectively,which is obviously higher than that of phoxim 3% GR at 675 g a.i./ha.[Conclusions] At the concentration of 1875 g a.i./ha,chlorpyrifos 5% GR could be used to effectively control B.odoriphaga.