Location: Mosquito and Fly Research
Project Number: 6036-32000-050-73-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Oct 1, 2017
End Date: Jul 31, 2018
1. Perform dose-response and mating competitiveness experiments with strains of Aedes. (Ae.) aegypti derived from Lee County and St. Augustine, Florida. The outcome will be to determine radiation doses that generate complete male sterility, while maintaining male mating competitiveness. 2. Perform field mark-release-recapture experiments with sterile males in St. Augustine and Lee County to: A) assess the dispersal ability and duration of presence of sterile males under field conditions, and B) estimate wild Ae. aegypti population densities at each field site. The outcome will be to estimate the number of sterile mosquitoes needed for releases and the frequency of releases needed to suppress wild Ae. aegypti populations in these locations.
Aedes (Ae.) aegypti mosquitoes will be collected from field sites in two counties in Florida and be used to start a laboratory colonies. Male mosquitoes will be treated with doses of ionizing radiation to generate sterility by inducing dominant-lethal double stranded DNA breaks in sperm. Doses will range from 0-100 Gy in 10 Gy increments to determine a dose for 100% male sterility that maintain male performance. Male sterility at each dose will be assessed by mating groups of 50 irradiated virgin males to 50 non-irradiated virgin females in 30 x 30 x 30 cm cages. Once we identify effective doses for male sterility, we will also compare the ability of non-irradiated and irradiated males from each source population to compete against non-irradiated males of the other source population for the female of the other source population. Once small cage assays have been performed and a benchmark radiation dose selected, we will test for male mating competitiveness in larger, semi field cages. We will perform field releases of sterile male Ae. aegypti at sites in Fort Myers and St. Augustine to estimate sterile male dispersal, sterile male residence time in the field, and quantify field Ae. aegypti population densities to estimate numbers needed for future suppressive field releases.