Application And Purification Of Insecticide Susceptible Strain Of Aedes Albopictus

Chemical control is most commonly used method in mosquito andepidemic situation,A large number of insecticide unreasonable used in the long term will not only cause the great pollution to the environment.More importantly,mosquitoes will gradually produce resistance to insecticides,so monitoring resistance to mosquitoes is particularly important.In this study,the sensitivity of sensitive strains of Ae.Albopictus(JS)to common insecticides was determined by biological assay.the susceptible strain of Aedes albopictus(JS)was reproduced in the laboratory for the 2 generation by alpha-cypermethrin,and a more sensitive JS-SUS strain of Aedes albopictus was obtained.Test the larval LC50 of JS-SUS andthe adult LC50 and LC99 of JS-SUS strain.Enzymatic susceptibility was also tested on both larval and adult Ae.albopictus,including non-specific esterase(NSE),mixed function oxidase(MFO)and glutathione S-transferase(GST).And compare with its parent.At the same time,the knockdown resistance(Kdr)of adults was detected at molecular level.Also compare with its parent.At present,most of the field vectors of Aedes are highly resistant to pyrethroids in our resistance monitoring system,in this case,we choose diflubenzuron which represented:insect growth regulator to do sensitivity analysis to resistance strain and susceptible strain.The results of this study were summarized as following:1.the larval LC50 of JS strain were:Deltamethrin 0.000469mg/L,permethrin 0.00182mg/L,alpha-cypermethrin 0.003180mg/L,betacypermethrin 0.000536mg/L,lambdacyhalothrin 0.000524mg/L,temephos 0.00132mg/L,malathion 0.013995mg/L,fenitrothion 0.016649mg/L,DDVP 0.024432mg/L,propoxur 0.265254mg/L,bendiocarb 0.615237mg/L,DDT 0.019053mg/L.2.the adult LC50 of JS strain were:Deltamethrin 0.0965%,alpha-cypermethrin 0.0177%,permethrin 0.0965%,betacypermethrin 0.0141%,lambdacyhalothrin 0.0215%,temephos 0.0711%,malathion 0.1050%,fenitrothion 0.0267%,DDVP 0.0565%,propoxur 0.0033%,bendiocarb 0.004%.3.In this study,thefirst reverse selective breeding study,the 100 pairs of single female were paired and 55 pairs spawned eggs at the end,The spawning range is between 4 and 169,the average amount of egg production was 84,and the amount of egg laying mainly between 50-142 grains.the second was 40 pairs of single female were paired and 27 pairs spawned eggs at the end,The spawning range is between 76 and 140,the average amount of egg production was 109,and the amount of egg laying mainly between 106-126 grains.4.the larval LC5o of JS-SUS strain was 0.00115mg/L to alpha-cypermethrin,it is 2.77 times lower than before,the adult LC50 and LC99 of JS-SUS strain were 0.0056%and 0.0307%respective,it is 3.16 and 24 times lower than before.After selecting,the sensitivity of alpha-cypermethrin to adult and larvae increased significantly.The slope of the mosquito toxicity regression line increased from 1.435 to 3.152.the purity increased significantly after selecting.5.We tested the enzymatic activity of NSE,MFO and GST for JS larvae,114.97 nmol ?-NA/(min·mg pr)?6.42 nmol cyt c/mg pr?42.56nmol/(min·mg pr)respectively,and JS-SUS larvae,44.96 nmol?-NA/(min.mg pr)?4.55 nmol cyt c/mg pr and 17.24 nmol/(min.mg pr)respectively;62.67 nmol a-NA/(min·mg pr)s 4.37 nmol cyt c/mg pr?45.72 nmol/(min-mg pr)respectively for JS adults;12.3 nmol ca-NA/(min-mg pr)?1.53 nmol cyt c/mg pr?22.75 nmol/(min·mg pr)respectively for JS-SUS adults.Compared with JS,the activity of the three metabolizing enzymes of JS-SUS decreased significantlyin adult larvae.At the molecular level,JS found mutations at the 1534 site(2/64),from phenylalanine(F)to serine(S),but no mutation was found in JS-SUS.At the biological,biochemical and molecular level,the sensitivity of JS-SUS strains was improved after selecting.6.The IE50s of the resistant strains Ae.Albopictus and Ae.aegypti were 0.00253 ug/ml and 0.00233ug/ml,the resistant ratio were 1.71 and 1.77.Indicating that no cross resistance of diflubenzuron and pyrethroid.