阿维菌素对小菜蛾的抗性选育及其对解毒酶活性的影响

用阿维菌素对小菜蛾Plutella xylostella (L.)进行了抗性选育，并对选育过程中小菜蛾解毒酶的活性进行了研究。选育从F₀至F₂₁代，抗性缓慢波动上升，达到选育前的122.91倍；F₂₁至F₂₇代，抗性迅速增长，达到选育前的812.73倍，抗性发展趋势呈现S型曲线。随着选育代数的增加，对乙酰胆碱酯酶(AChE)没有明显的影响；羧酸酯酶(CarE)活性,F₂₇是F₀的1.5倍，从F₂₂开始，活性在较高水平上波动；谷胱甘肽转移酶(GST)活性F₂₇是F₀的2.2倍，且从F₁₈开始，活性在较高水平上波动。选育的抗性品系，增效醚对阿维菌素增效6.34倍。

Author for correspondenceStudy on resistance selection by avermectins and its effect onactivities of detoxification enzymes inPlutella xylostella(L.)

The resistance selection of diamondback moth (DBM), Plutella xylostella (L.), to avermectins (AVMs) and its effect on activities of detoxification enzymes in AVMs selected DBM were investigated during 1996～1999. After 27 generations of continuous selection pressure, resistance to AVMs was over 812-folds in this strain compared with the unselected parents. Resistance selection by AVMs has no effect on activity of acetylcholinesterase (AChE). The activities of carboxylesterase (CarE) and glutathione S-transferases (GST) in DBM larvae of F₂₇ generation increased 1.5 and 2.2-folds respectively, compared with the unselected parents (F₀). Piperonyl butoxide (Pb) can moderately increase the toxicity of AVMs to the selected strain for about 6-folds. It suggests that the resistant mechanisms of DBM to AVMs were probably associated with microsomal mixed function oxidases (MFO), GST and CarE.