Post‐treatment effects of sublethal doses of dieldrin on the mosquito Aedes aegypti L

SUMMARY Sublethal doses of dieldrin were topically applied to individuals of the mosquito Aedes aegypti L., and the effects on feeding, egg laying and mortality observed. The highest dose of dieldrin (0·0075 μg./insect) stopped the feeding of 2‐ to 3‐day‐old blood‐fed females. Egg laying continued up to 96 hr. after treatment but then dwindled and finally stopped. Lower doses induced diminished responses and the lowest amount of insecticide applied (0·0016 μg./insect) had no effect. Females (1–2 days old) were treated with 0·0060 μg./insect. Of the survivors, very few fed on subsequent days and only a small number of eggs were laid by them. Dieldrin apparently had no effects on the viability of the progeny from the treated adults. It is concluded that the insecticide primarily affects feeding; egg laying and longevity suffer as a consequence.