Preparation and application of esterase B1 and A2 probe for detection of the resistance of anti-DDVP Culex pipiens pallens

Objective To prepare the esterase B1、A2 probe of DDVP resistant Culex pipiens pallens and detect resistant level of Culex pipiens pallens. Methods Forward-Primer and Reverse-Primer of esterase B1、A2, were designed and labeled with digoxin on 5’ end of Forward-Primer of esterase B1、A2. DNA probe was prepared by PCR and used for identification and screening the DDVP resistance of Culex pipiens pallens. Results The probe concentration suitable for the differentiation of resistant and sensitive strains were ascertained by repeated experiment. In this concentration, the positive rate of hybrid were different among all strains. It shows that with use of esterase Bl probe the positive rates of the strains resistant to DDVP,proproxur and permethrin were 40%,23% and 18.3%,respectively,while by use of esterase A2 probe the positive rates of the strains to DDVP,propoxur and permethrin were 43%,25% and 11.7%,respectively. Conclusion The different resistant strains can be distinguished with esterase B1 probe and esterase A2 probe, thereby we can apply it to detect every sesistant strains. This provided a practical molecular biological method for gene detection of DDVP resistant vector insects.