Toxicity of Insecticides to Bradysia odoriphaga at Different Temperatures and Their Control Effect in the Fields

Taking 5kinds of pesticide as test drug and Bradysia odoriphagaas test pest,the effect of temperature on toxicity of seclected insecticides on Bradysia odoriphagawas evaluated,the toxicities of 5insecticides in 8、16、24℃ were studied with dripping ration liquid method,and their control efficiency in the field were also studied.The results showed that the toxicities of 5insecticides showed positive temperature effect.Among these insecticides,Imidacloprid showed the most obvious positive temperature effect,toxicity of Imidacloprid in 24℃ was 4.66times higher than that in 8℃. Methomyl,Clothianidin and Thiamethoxam's positive temperature effect were similar,and the positive temperature effect of Emamectin benzoate was minimum.In pot test,Emendation larvae mortality was 75.2% when roots were irrigated by Clothianidin 50 mg/L,which was 14.5%,24.8% and 28.2% higher than the same dose treatment of Methomyl, Imidacloprid and Thiamethoxam respectively.In field test,Clothianidin 100 mg/L and 50mg/L irrigating roots treatments were the best when processed 25days.The pesticide effect of Clothianidin were 100% and 95.2% while control efficiency of Methomyl 200mg/L was 84.2%.Pesticide effect of Imidacloprid and Thiamethoxam 100mg/L irrigating roots were 93.7%and 96.9%respectively,which were also better than Methomyl 200mg/L and 100mg/L. The 3kinds of neonicotinoids all had good pesticide effect on Bradysia odoriphaga.Among them,Clothianidin was outstanding and had a persistent control function on Bradysia odoriphaga.It was environment friendly and very suitable for the application in the fields.