Bioactivity and sublethal effects of benzoylphenylurea insecticides on Apolygus lucorum
Abstract
This paper systematically compares the bioactivity and sublethal effects of four benzoylurea insecticides on Apolygus lucorum(Meyer-Dur).The results show that all four insecticides possess high toxicity to the nymphs of this pest.More specifically,chlorfluazuron had the highest toxicity to 2nd instar nymphs of A.lucorum(LC50 of 51.63 mg/L),hexaflumuron had the highest toxicity to 3rd instar nymphs(LC50 66.87 mg/L) and triflumuron had the highest toxicity to 4th instar nymphs(LC50 of 93.04 mg/L).The toxicity of all three of these insecticides was higher than that of malathion.Additionally,sub-lethal doses(i.e.LC30—40) of these insecticides significantly influenced the growth,development and survival of A.lucorum.Among the four insecticides tested,hexaflumuron had the greatest sublethal effects.2nd instar nymphs treated with this insecticide had a slower developmental rate and the subsequent adults had less fecundity and shorter longevity.The survival of 4th instar nymphs was also reduced by sublethal doses of this insecticide.