氟虫腈对小菜蛾3龄幼虫取食、化蛹、羽化的影响

在研究了氟虫腈对小菜蛾3龄幼虫室内毒力的基础上,观察了氟虫腈对试虫取食、化蛹、羽化的影响。在所研究浓度下,氟虫腈对试虫存活个体、死亡个体的平均取食量都无明显影响,但0.20 mg/L氟虫腈处理过的试虫总取食量增加了22%,其余处理的总取食量都有所下降,12.50 mg/L氟虫腈处理过的试虫总取食量下降了70%。氟虫腈处理还会导致蛹重略有下降,推迟试虫平均化蛹时间,CK的平均化蛹时间为110 h,12.50 mg/L氟虫腈处理过的试虫平均化蛹时间为177.6 h,显著延长（P〈0.05）。

Effect of Fipronil on Feeding,Pupation and Adult Emergence of 3rd Instar Larvae of Diamondback Moth,Plutella xylostella(Linnaeus)

Based on the indoor toxicity test of Fipronil to the 3rd instar larvae of diamondback moth(Plutella xylostella(Linnaeus)),the effect of Fipronil on feeding,pupation and adult emergence of the tested insect was studied.At the chosen concentrations,no effect on the average feeding amount either for the dead or survival individuals was found.The treatment of Fipronil at 0.20 mg/L could increase the total feeding amount of the tested insect by 22%,while the other treatments could decrease the total feeding amount and the highest decreased rate was 70% when Fipronil was at 12.5 mg/L.Besides,Fipronil treatment could reduce pupal weight a little and postpone pupation.The average pupation time in the check was 110 h,while that was 177.6 h when the insect was treated with Fipronil at 12.50 mg/L.