Analysis Of Musca Domestica Resistance And Genetic Mutation Frequency Of Vssc And Ace In Partial Cities Of Guizhou Province

Objective:To understand the current resistance of the city housefly to the pyrethroid and the organophosphorus insecticide in Anshun,Chishui,Guiyang,Huishui,Kaili,Liupanshui and Zunyi of Guizhou Province,calculate the frequency of the mutant Vssc and Ace,and provide a scientific foundation for the housefly control in Guizhou Province.Methods:Houseflies were collected from the places mentioned above with nets and carried to the laboratory to breed regularly.The median lethal dose was calculated with the drop method of housefly bioassay.Vssc was amplified by PCR Amplification of Specific Allele and the genotype was identified with the result of agarose gel electrophoresis.Ace was amplified and sequenced to detect the genotype.The relationship between the mutant frequency and the housefly resistance was figured by statistics.The analysis of genetic structure was computed by the software Arlequin 3.5.Results:The median lethal dose of beta cypermethrin,permethrin,deltamethrin,dichlorovinylphosphate and temephos were 0.084⁰.24885,0.0973⁰.3703,0.04935⁰.15085,0.56865¹.21415 and 13.8005⁴1.12605?g per housefly respectively,and the resistance ratio were 27.36⁸1.06,7.48²8.48,78.33²39.44,142.16³03.54 and 122.13³63.95.To Vssc,all populations were found with mutations except for Population HS where the F_ST was from 0.05177 to0.13131?P<0.05?compared with all of the other populations while the FST was from0.05247 to 0.09428?P<0.05?among the other populations.There were 5 genotypes identified in the seven populations and the mutant frequency,from 0 to 15%,had a coefficient of determination under 0.4818 with the resistance.The Hardy-Weinburg Equilibrium test indicated that the P values of the observed and the expected heterozygosity at locus 1014 of Vssc were over 0.05.To Ace,mutations happened at locus 260,342 and 407 in all populations with a high frequency at 27.4⁷3.8%of260L,59.1⁷6.7%of 342A,23.7⁴0.9%of 342V and 83.4¹00.0%of 407Y.There were 8 genotypes and 11 mutant combinations detected,in which the combination of V/L+A+Y showed a significant correlation with the dichlorovinylphosphate resistance.The Hardy-Weinburg Equilibrium test illustrated that the P values of the observed and the expected heterozygosity at locus 260 of Population KL and ZY,locus 342 of Population GY and KL,and locus 407 of Population CS,GY,HS,KL and LPS of Ace were above 0.05.The Linkage Disequilibrium test demonstrated that locus 260 and 342 had a significant linkage?P<0.05?in all populations.The F_STT among populations was from 0.03563 to 0.08246?P<0.05?.The coefficient of determination of Vssc F_ST and the geographic distance was 0.03658,and 0.07403 for Ace FST with the geographic distance.Conclusion:The housefly from Anshun,Chishui,Guiyang etc.of Guizhou Province generated the resistance to the pyrethroid and the organophosphorus insecticide.The mutant Ace frequency was very high,at locus 342 and 407,among populations.Both Vssc and Ace had a genetic differentiation among populations.Some resistant loci were in a linkage disequilibrium and deviated from the Hardy-Weinburg Equilibrium.The relationship between the genetic distance in Vssc and Ace.