ABSTRACT
Objective:To observe the fumigating insecticidal activity of 5 essential oils(asteraceae oil,rutaceae oil,mentha piperita oil,carvacryl oil and citronella oil) against Culex pipiens quinquefasciatus.Methods: Fumigating insecticidal activity was investigated by airtight fumigation in conical flask.Results: After different fumigating time,5 essential oils showed different toxity against Culex pipien quinqucfasciatus.Of 5 essential oils,rutaceae oil was the most toxic, with the LC 50 values being 0.013(0.5 h),0.055(4 h) and 0.058(24 h); asteraceae oil was the lowest toxic one, with the LC 50 values being 0.948(0.5 h),0.427(4 h) and 1.711(24 h).When LC 95 values of the 5 essential oils were used to treat Culex pipiens quinquefasciatus,the shortest fumigating time appeared in carvacryl oil(6.087 min) and the longest in citrinella oil(21.143 min).Conclusion: All the 5 essential oils have considerable insecticidal effects against Culex pipiens quinquefasciatus.Rutaceae oil and carvacryl oil are better than the others,which provides basic informations for the related field experiments.