四种低毒杀虫剂对小菜蛾生长发育及繁殖的亚致死效应

Sublethal effects of four low-toxicity insecticides on the development and reproduction of the diamondback moth,Plutella xylostella(Lepidoptera: Plutellidae)

为系统评价4种低毒杀虫剂对小菜蛾Plutella xylostella（L.）的综合控制作用，采用叶片浸渍法处理小菜蛾3龄幼虫，测定了虫酰肼、氟啶脲、茚虫威和虫螨腈的亚致死浓度（LC25）对小菜蛾生长发育和繁殖力的影响。结果表明，4 种药剂亚致死浓度处理使小菜蛾3~4龄幼虫发育历期延长0.43~1.93 d，平均单头雌、雄蛹重分别减轻0.83~1.31 mg和0.19~1.09 mg ，幼虫的化蛹率及羽化率则分别降低11.2%~34.3%和21.7%~33.6%，以氟啶脲和茚虫威处理的影响较为显著。药剂处理后成虫平均产卵量减少30.15~60.21粒/雌，卵孵化率降低8.85%~19.65%，以虫酰肼效果较为明显；虫酰肼、氟啶脲、茚虫威均显著降低小菜蛾的交配成功率。

To systematically evaluate the integrated effects of the four selected low-toxicity insecticides on controlling the diamondback moth （DBM）, Plutella xylostella （L.）, the effects of tebufenozide, chlorfluazuron, indoxacarb and chlorfenapyr at sublethal concentrations （LC25） on DBM＇s development and fertility were tested with leaf immersion treatment against the 3rd instar larvae. The results indicated that the larval duration from 3rd to 4th instars of live DBM was prolonged by 0.43-1.93 days, average pupal weight of individual females and males decreased by 0.83-1.31 mg and 0.19-1.09 mg, respectively, and the pupation rate and emergence rate decreased by 11.2%-34.3% and 21.7%-33.6%, respectively. Chlorfluazuron and indoxacarb showed more significant inhibition to DBM development than the other two low-toxicity insecticides. The fecundity of live DBM reduced by 30.15-60.21 eggs per female, and hatchability decreased by 8.85%-19.65%, and tebufenozide caused more significant inhibition to DBM fecundity than the other three selected insecticides. Tebufenozide, chlorfluazuron and indoxacarb significantly decreased the mating success of DBM.