Resistance of Culex pipiens pallens to four kinds of insecticide

Objective To investigate the resistance of Culex pipiens pallens larvae to 4 kinds of common used insecticide in Qingdao,and guide the control of Culex pipiens pallens larvae by choosing appropriate chemical insecticide.Methods Insecticidal resistance of Culex pipiens pallens larvae was measured using a standard WHO bioassay.Results Compared with the laboratory susceptible strain,the resistance of Culex pipiens pallens larvae to DDVP and propoxur was in lower level. Its resistance to trichlorine was in medium level. Culex pipiens pallens larvae to cypermethrin had the highest resistance. Conclusion Culex pipiens pallens in Qingdao has generated different degrees of resistance to the 4 kinds of common used chemical insecticides. Therefore appropriate measures should be taken to prevent or delay the emergence and development of insecticidal resistance in mosquitoes.