Idrissa Kaboré

Mating performance of Glossina palpalis gambiensis strains from Burkina Faso, Mali, and Senegal

The mating performance of Glossina palpalis gambiensis Vanderplank (Diptera: Glossinidae) mass‐reared in Burkina Faso (BKF strain) was compared with that of target populations originating from the Bamako peri‐urban area of the Niger River Basin, Mali (MLI strain) and the Niayes area, Senegal (SEN strain). The tests were carried out using a field cage either set up outdoors in Burkina Faso or inside the laboratory in Austria. The target population strains (MLI and SEN) were a few generations from the wild whereas the laboratory‐reared flies (BKF) were adapted to laboratory rearing over many generations. The laboratory‐reared BKF strain significantly out‐competed the MLI strain in the mating tests, but showed close to equal competitiveness with the SEN strain. At least one‐third of possible matings occurred during each observation period. The females from the two target populations readily mated with males from the BKF strain. The selected mating parameters and behaviour in the cage showed that there was mating compatibility between the strains and this absence of obvious mating barriers indicates the potential of using BKF strain males in programmes that have a sterile insect technique (SIT) component targeting the two G. p. gambiensis populations of Mali and Senegal.

Storage of male Glossina palpalis gambiensis pupae at low temperature: effect on emergence, mating and survival

BackgroundProcurement of sterile tsetse flies (Glossina palpalis gambiensis) from Burkina Faso for an eradication programme in Senegal that incorporates the sterile insect technique (SIT) required the development of transport and handling protocols that would allow retaining the female flies in the rearing facility and transport of the male flies as irradiated pupae. The proposed handling scheme included the chilling of the male pupae after the female emergence and transport to Senegal under low temperatures. The effect of exposing male pupae of G. p. gambiensis to low temperature immediately prior to emergence was investigated.MethodsThe parameters of interest were emergence rate, insemination potential, survival of adult male, male ability to participate in mating activities and productivity of females mated with these males. Production was assessed in laboratory rearing cages and mating behaviour in field cages. Male flies that emerged after the female emergence flush from pupae stored at 10°C or 12.5°C for 5 or 7 days were used in the investigations with flies that emerged under standard colony conditions as control. Males that were 3, 6 or 9 days old competed for mating opportunities with 3 day old females.ResultsThe emergence of males after storage of pupae at low temperature (10°C and 12.5°C) for 3, 5, or 7 days was similar to those kept under standard colony conditions while emergence of flies stored at 15°C started before the storage period was over. Survival of males that emerged from pupae stored at low temperature for varying periods was more than 60% at 30 days post emergence (control more than 75%). The fecundity of females inseminated by males that emerged from pupae stored at low temperature for varying periods ranged from 0.33–0.16 to 0.73–0.04 pupae per female per 10 days (control 0.60–0.16). The older males, irrespective of treatment, out-competed the younger males and 3 day- old males transferred lower amounts of seminal contents to the females.ConclusionsStorage of male pupae at low temperature for periods up to 7 days at the end of the male pupal period could not be directly associated with impairment of mating activity.