Current insecticide resistance of Culex pipiens quinquefasciatus in different habitats in Nanchang, China.

Objective To determine the resistance of Culex pipiens quinquefasciatus in different habitats in Nanchang to 6 kinds of insecticide such as dichlorvos,providing the basis for development of control measures.Methods The larvae,eggs and adults of Cx.pipiens quinquefasciatus were collected from different habitats in the east,south,west,north and central part of Nanchang city.After 1 to 2 generations of laboratory breeding,the insecticide resistance of the subjects was measured by the impregnation method.Results The resistance coefficients of the mosquitoes from 5 different habitats were 1.19-2.05,0.57-1.80 and 0.57-1.73 times to propoxur,temephos and dichlorvos,suggesting that the mosquitoes were sensitive to these insecticides.Their resistance coefficients to pyrethroids such as permethrin and cypermethrin were 5.33-56.83 and 10.39-42.17 times,indicating different degrees of resistance.Conclusion There were no insecticide resistance of Cx.pipiens quinquefasciatus against propoxur,temephos and dichlorvos in different habitats in Nanchang,China.On the contrary,there were midium and high resistance against permethrin and cypermethrin.The monitoring of its inseticide resistance should be strengthened in conjunction with proper application of insecticides in order to delay resistance evolution.