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The housefly,Musca domesticaL.,is a significant pest of medical and veterinary importance all over the world.Managing efforts for domestic flies are generally threatened due to their resistance to many groups of conventional insecticides.Cantharidin,a natural toxin produced by meloid beetles,is a biopesticide with reported toxicity to some insect pests,including houseflies.However,the effects of cantharidine on the biological and ecological parameters of domestic flies have not yet been investigated.In this study,we examined the toxicity and sublethal effects of cantharidine on the biological parameters of the housefly for two consecutive generations.The results showed that LC50,LC25,LC10and LC2against females of housefly had to be 2.45,1.23,0.66 and 0.30 mg liter-1.The sublethal effects of these concentrations on the parameters of the development and reproduction of houseflies have shown that cantharidine reduces populationgrowth by affecting the number of adolescents,adult growth,and prolonging development time.The ratio of females,fertility,egg hatching, and survival of adult flies were significantly reducedin the LC2,LC10,LC25,LC25and LC50cantharidin compared to the control group.In addition,the increase in cantharidine concentration had a significanteffect on the decrease in mean relative growth rate(MRG),net reproduction rate(R0),natural growth rate(r)and biotic potential(bp).In conclusion,the results of this study revealed the toxicity of cantharidine against domestic flies and the adverseeffects of sublethal concentrations on biological parameters,which may have positive consequences for effective control of domestic flies. Cantharidine is a highly effective,well known natural toxin in China produced by beetles of Meloidae and Oedemeridae belonging to order Coleopteran insects.The insecticidal efficacy ofcantharidine against various insect orders has been well documented.Although highly efficient,its extraction and synthesis is very difficult.As a result,much work is being done onthe synthesis of norcantharidine bioactive analogues and the study of their relative structures. In this study,we investigate the acute and chronic toxicological effects of cantharidin and endothall,an analogue of norcantharidin,based on the age-stage,two-sex life table theory.Results reveal the acute toxicity of these compounds toSpodoptera litura,with the LC50of cantharidin being 2.10 and endothall being 3.72 ppm.Although both compounds negatively affected the population parameters,cantharidin was slightly more effective.Among the reproductive parameters,fecundity was severely affected bycantharidin,which reduced offspring to 42 compared to 528 per female in the control cohort.Both cantharidin and endothall caused similar physiological changes such as weight reduction,wing malformation and pupal deformities. These findings demonstrate that both cantharidin and endothall are highly toxic toS.litura,particularly in their chronic effects on population parameters.This will help us to understand the biological and ecological interactions in agricultural cropping systems and how their application will modify insect herbivory. Mythimna separatais a polyphagous insect pest of sporadic occurrence.Thiamethoxam is a neonicotinoid insecticide used to treat many pests in many parts of the world.Selected and susceptible to thiamethoxam strains based on laboratory observations were investigated for the selection of resistance strategy,resistance selection,larval parameters,and biochemical mechanisms of thiamethoxam resistance.The results of our bioassay showed that the strain selected fromthiamethoxam was 17.03-fold more resistant than the susceptible strain.The thiamethoxam strain selected had a shorter body texture length of larvae,a lower body weight of males and a shorterpreadult development time than the susceptible strain.Biochemical analyzes have shown that theenzymes GST,CarE and cytochrome P450 are associated with the development of thiamethoxam resistance in theM.separatastrain selected from thiamethoxam.In this study,the incidence of resistance may become developmentalsuitability for a selected strain of thiamethoxam and provide useful information for designing strategies to control resistance delays