Toxicity Test of Three Pesticides on Erythroneura sp.Nawa and Control Effect in Field

Contacting toxicity test of three pesticides,namely beta cypermethrin,matrine,imidacloprid,on Erythroneura sp nympha in laboratory by drug membrane method and control effect in field was conducted.The results showed that the range of contacting mortality rate of Erythroneura sp nympha was beta cypermethrin,matrine and imidacloprid.And the median lethal concentration(LC50) of three pesticides against the pests were 0.461 6 mg·L-1,1.084 0 mg·L-1,1.160 2 mg·L-1 in 24 hours,respectively.The dropping rate of pest and correct effectiveness of all concentrations of beta cypermethrin,3.80 mg·L-1 matrine were well obtained in 7 days of chemicals spraying.