Study On Molecular Detected Medthod Of Pyrethroid Insecticide Resistance Of The Vector Mosquito In Field

Insect-borne diseases are public health problems have always been endangeringhuman health. Especially, in most parts of my country is rich in the vegetation, issuitable for the climate, and because of the rapid development of economy, thefloating population keeps increasing, the part of insect-borne disease outbreak may atany time. Therefore, increased the threat of insect-borne diseases, further strengthenmedia control is an important way to deal with public health emergencies. Chemicalcontrol is the main method for mosquito control. Pyrethroid is a kind of popularinsecticide, at the same time, it has the most serious drug resistance in the word.Therefore, mosquito resistance has become a worldwide outstanding problem inmosquito prevention and control of vector-borne diseases.Object：To investigate the deltamethrin resistance in Culex pipiens pallens andthe association with the knockdown resistance mutation and to explore theestablishment of mosquito resistance testing method for the control of mosquito-bornediseases in Shandong province.Method: Kdr gene sequences was isolated from different parts of wild Culexpipiens pallens mosquitoes using specific primers by PCR and AS-PCR technique,andsequenced. Using the linear regression analysis to determine the relationship betweenthe mutation and deltamethrin resistance. Result: Knockdown resistance allelic gene was cloned and sequenced. Analysisof DNA sequences revealed the presence of two point mutations at L1014residue inthe IIS6transmembrane segment of vgsc, i.e., L1014F TTA mutaions as TTT, thecorresponding leucine (L) by phenylalanine (F) replaced; L1014S;TTA mutaions asTCA, the corresponding leucine (L)(S) replaced by serine. Two alternative kdr-likemutations, L1014F and L1014S, was positively related to deltamethrin resistantphenotype.The results are basically the same by PCR and AS-PCR technique inmosquito restance.Conclusion: Two alternative kdr-like mutations in Culex pipiens pallens waspositively related to deltamethrin resistant phenotype. Further studies are needed todetermine the specific resistance mechanism. RT-PCR and AS-PCR technique can beapplied to the mosquito resistance field test.