Studies on insecticide resistance of Cx. pipien pallens by filter paper test of esterase

In order to establish a simple and sensitive method for early prediction of mosquito insecticide resistance, the esterase activity of laboratory and fetid strain of Cx. pipien pallens was detected with filter paper test by using α-naphthyl acetate as the substrate and fast blue B salt as the colour agent. The results showed that the resistant individual frequency of DDVP-resistant Strain was the highest of three resistant Cx. pipien pallens strains, followed by anti-propoxur strain. The frequency of anti-pyrethroid was fairly low and similar to that of susceptible strain. Three field strains of Cx. pipien pallens were all resistant to DDVP and propoxur at different level and the resistant individual frequency of them was all fairly high. Filter paper test can be used to detect the resistance level of mosquito to OPs and propoxur. This method is quick, sensitive, easy to operate and the results can be easiely observed therefore it is a practical method for the field detection of esterase activity of mosquitoes.