Developmental Effects of Ethyl Methanesulfonate and Thiotepa in Aedes Aegypti (Diptera: Culicidae)1

Abstract

The effects of various concentrations of a monofunctional alkylating agent, ethyl methanesulfonate (EMS), and a trifunctional alkylating agent, thiotepa, on 3 stages in the development of the PUGU strain of Aedes aegypti were tested. Eggs, pupae, and adult populations were treated with 0.025%, 0.050%, 0.075%, and 0.10% concentrations of the chemomutagens. Viable adults derived from the treated eggs and pupae were cross-mated, as were the treated adults. Egg production, percentage hatchability, viability, and productivity in the Fl generation were employed to measure the developmental effects. Treatment with EMS did not significantly reduce egg production, percentage hatchability, or total productivity when administered at any of the 3 stages. However, thiotepa induced sterility at all concentrations when male and female adults were treated. Sterility was induced in eggs treated with thiotepa at concentrations of 0.050% and 0.075%; a significant decrease in productivity was shown at both 0.025% and 0.10% thiotepa. Significant reductions in total mean F1 progeny were found at the 0.050%, 0.075%, and 0.10% concentrations of thiotepa when the pupae were treated. Overall, EMS was less effective in altering the life cycle of Ae. aegypti than was thiotepa.