溴虫腈对小菜蛾3龄幼虫存活、化蛹和羽化的影响

在用浸叶法测定溴虫腈对小菜蛾3龄幼虫毒力的同时,观察了溴虫腈对小菜蛾存活、化蛹和羽化等的影响。结果表明,溴虫腈对小菜蛾没有后效性,随着时间的推移,不同浓度的死亡率没有明显变化;在所有测定浓度下,溴虫腈对小菜蛾幼虫体重、蛹重、幼虫至蛹历期和蛹期与对照相比没有明显影响;尽管不同浓度处理化蛹率和羽化率都低于对照,但只有高浓度(10mg·L-1和20mg·L-1)和2.5mg·L-1处理与对照相比差异显著,低浓度(0.625mg·L-1和1.25mg·L-1)和5mg·L-1处理与对照相比差异不显著。

Effect of Chlorfenapyr on Survival, Pupation and Adult Emergence of the Third Instar Larvae of Diamondback moth, Plutella xylostella (Linnaeus)

Together with the indoor toxicity test of chlorfenapyr to the third instar larvae of diamondback moth,Plutella xylostella(Linnaeus,1753)(Lepidoptera: Yponomeutidae),the effect of chlorfenapyr on survival,pupation and adult emergence of the tested insect was studied.The results showed that chlorfenapyr had no aftereffect on P.xylostella,and with the passage of time,mortalities at different concentrations had no obvious change.Larval weight,pupal weight,the duration of the third instar larvae to pupation and pupae were similar to the control in all treatment groups.All tested concentrations of chlorfenapyr caused decrease in pupation rate and adult emergence rate compared with the control.However,only the higher concentrations(10 and 20 mg·L-1) and 2.5 mg·L-1 were significantly lower than the control,the lower concentrations(0.625 and 1.25 mg·L-1) and 5 mg·L-1 were not significantly different from the control.