Quality Control and Mating Performance of Irradiated Glossina palpalis gambiensis Males

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Résumé

The biological quality of sterile male insects produced in a mass-rearing facility is a
prerequisite for the success of the SIT, which is a component of area-wide integrated pest management
(AW-IPM). Indeed, sterile male insects released in the field must have a good mating performance
in order to compete with wild males, but they must also present the required level of sterility. In
the present study, the biological quality of sterile male Glossina palpalis gambiensis produced in a
mass-rearing insectary was assessed through quality control testing. The mating performance of
irradiated males was assessed in walk-in field cages. Irradiation had no effect on adult emergence but
significantly reduced the percentage of operational flies (from 89.58% to 79.87%) and male survival
(from 5 to 4 days, on average). However, irradiation did not impact the sterile male insemination
potential, with all females inseminated and more than 80% of the spermathecae completely filled.
The rate of induced sterility in females was 89.67% due to a dose rate decrease of the radiation source.
Moreover, sterile males were able to compete successfully with untreated fertile males for untreated
females in walk-in field cages. This study confirmed that the flies were still competitive and stressed
the importance of regularly checking the radiation source parameters.

Mots-clés

sterile insect technique; tsetse fly; sterility rate; competitiveness