Submitted to: Joint Expert Consultation Committee
Publication Type: Proceedings
Publication Acceptance Date: 12/10/1999
Publication Date: N/A
Interpretive Summary: Wild tsetse flies of the same species appear in widely separated locations in Africa, and this could make a difference when sterile males flies are going to be released in new locations to fight sleeping sickness. Flies reared for release should smell very much like wild flies. Scientists at the Center for Medical, Agricultural and Veterinary Entomology in Gainesville, Florida studied the sex pheromones that are specific to each of two species. The unsaturated hydrocarbons from all laboratory and wild Glossina austeni females from 7 countries appeared to be very similar. But in the surface waxes of the same specimens, South African and Mozambique females were most alike, differing from females from further north. Similarly, the wax from female G. pallidipes from several locations were similar across populations in Ethiopia and Kenya, but the Zimbabwe wild flies differed most. This kind of information should help quality control during international efforts to control these flies.
Technical Abstract: Different populations of wild tsetse flies of the same species may contain similar surface hydrocarbons, including species-specific contact sex pheromones, when comparing individuals. The structure and relative abundances of all alkenes from laboratory and wild collected specimens of Glossina austeni females appeared to be similar. In contrast, the surface alkanes of the same specimens were analyzed and compared to determine similarities. South African and Mozambique females were most alike, and differed somewhat from females from further north. Similarly, the alkanes of female G. pallidipes from several locations were analyzed to determine differences and similarities with published work on the sex pheromone of the species. The known sex pheromone components were analyzed by GC-MS and were very similar across populations. If minor differences were investigated, females appeared to cluster into 2 groups; Zimbabwe wild and all others. The absolute meaning of these differences are not known, although the activity of synthetic sex pheromones was shown conclusively against Wageningen and ICIPE males in 1984-1986 tests, but they were less active against Zimbabwe males.