Resistant Level,Frequency of Non-specific Esterases and Genetic Differentiation in Mosquitoes Culex pipiens quinquefasciatus in Three Cities of Guangdong

Samples of mosquitoes Culex pipiens quinquefasciatus were collected in Guangzhou,Foshan,Zhongshan in Guangdong Province in May 2001.Bioassay and starch gel electrophoresis were used to determine their resistant levels to organophosphates and BPMC,and the distribution frequency of resistant-related esterases in the 3 populations.The resistant level of the 3 populations to dichlorovos was higher than the sensitive strain of Beijing at least for 21 times,parathion for 9 times,and BPMC for 5 times.The associated A8/B8 and A9/B9 were the main highly active esterases in the 3 populations,but regional differences appeared in esterase A2/B2 and B1.It was supposed that the difference will disappeared due to gene flow.