丁香酚对截形叶螨的杀螨活性及种群增长抑制作用OA

[Aim]Resistance of Tetranychus truncatus to chemical pesticides has become increasingly serious,whereas plant-derived compounds have shown great potential for the sustainable management of agricultural mite pests.This study aims to evaluate the acaricidal activity of five plant-derived compounds against T.truncatus and to explore the lethal effects of eugenol,the compound exhibiting high acaricidal activity,as well as the effects of parental exposure on the growth,development and reproduction of the F,offspring.[Methods]The leaf-dip bioassay was used to determine the laboratory toxicity of eugenol,α-terpineol,citral,linalool and carvacrol against female adults of T.truncatus.Furthermore,the effects of sublethal concentrations(LC10 and LC30)and median lethal concentration(LC50)of eugenol on the longevity,fecundity and population parameters of both the F0 and F1 female adults of T.truncatus were analyzed using the conventional life table technique.[Results]Toxicity test result revealed that eugenol exhibited obviously higher acaricidal activity against T.truncatus than the other compounds tested,with the LC50 value of 0.913％(v/v)against female adults at 48 h after exposure.Compared with the control(sterile water containing 0.1％Tween 80),LC10,LC30 and LC50 of eugenol significantly shortened the longevity of the F0 female adults of T.truncatus by 55.3％,65.4％and 85.3％,respectively,and reduced the number of eggs laid per female by 69.5％,84.1％and 95.9％,respectively.Tugenol exposure at all the three concentrations significantly reduced the net reproductive rate(R0)and mean generation time(T)of T.truncatus.Compared with the control,exposure to LC30 and LC50 of eugenol significantly inhibited the intrinsic rate of increase(r)and the finite rate of increase(λ)of T.truncatus,whereas only exposure to LC50 of eugenol significantly prolonged the population doubling time(t)of T.truncatus.In the F,generation,parental exposure to LC30 and LC50 of eugenol continued to exert significant transgenerational inhibitory effects on T.truncatus.After parental exposure to LC30 and LC50 of eugenol,the mean numbers of eggs laid per F1 female were 22.76±1.83 and 13.25±1.45,and the net reproductive rates(R0)of the F,adults were 23.25±3.22 and 13.48±1.76,respectively,significantly lower than those in the control group(39.22±2.82 and 43.54±4.93,respectively).[Conclusion]Eugenol not only possessed direct acaricidal activity against T.truncatus,but parental exposure also resulted in persistent inhibitory effects on the growth and development,reproduction and population growth of the F,offspring.These findings highlight eugenol as a promising lead compound for the development of novel plant-derived acaricides.