Citation: Ilboudo, K.; Camara, K.; Salou, E.W.; Gimonneau, G. Quality Control and Mating Performance of Irradiated Glossina palpalis gambiensis Males. Insects 2022, 13, 476. https:// doi.org/10.3390/insects13050476 Academic Editors: Kostas Bourtzis and Marc Vreysen Received: 12 February 2021 Accepted: 11 May 2022 Published: 19 May 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). insects Article Quality Control and Mating Performance of Irradiated Glossina palpalis gambiensis Males Kadidiata Ilboudo 1 , Karifa Camara 1,2 , Ernest W. Salou 1,3, * and Geoffrey Gimonneau 1,4,5 1 Centre International de Recherche—Développement sur l’Elevage en zone Subhumide, Bobo-Dioulasso 01 BP 454, Burkina Faso; kadidia124@gmail.com (K.I.); camarakariffa@gmail.com (K.C.); geoffrey.gimonneau@cirad.fr (G.G.) 2 Institut Supérieur des Sciences et de Médecine Vétérinaire (ISSMV), Dalaba BP 09, Guinea 3 Département de Sciences Biologiques/UFR-SVT, Université Nazi Boni (UNB), Bobo-Dioulasso BP 1091, Burkina Faso 4 Centre de coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), Unité Mixte de Recherche, Interactions Hôtes-Vecteurs-Parasites-Environnement dans les Maladies Tropicales Négligées Dues aux Trypanosomatidés (UMR INTERTRYP), F-34398 Montpellier, France 5 Interactions Hôtes-Vecteurs-Parasites-Environnement dans les Maladies Tropicales Négligées dues aux Trypanosomatides (INTERTRYP), Université de Montpellier, Centre de coopération Internationale en Recherche Agronomique pour le Développement (CIRAD), Institut de Recherche pour le Développement (IRD), F-34398 Montpellier, France * Correspondence: salouernest@gmail.com Simple Summary: In vector control programs based on the sterile insect technique (SIT), the bio- logical quality of sterile males must be as high as possible to compete with their wild counterparts. This study evaluates the biological quality and mating performance of sterile male Glossina palpalis gambiensis produced in a mass-rearing facility in Burkina Faso. It shows that irradiation had no effect on the adult emergence rate but reduced the percentage of operational flies and male fly survival. Irradiation had no effect on mating performances, as all females were inseminated, and the sterile males competed well with unirradiated males for virgin females in walk-in field cages. However, the sterility rate induced in females was lower than expected (89.67%). This study indicates that, under experimental field cage conditions, the G. p. gambiensis males produced at the CIRDES are well-suited for use in area-wide integrated pest management (AW-IPM) programs that have an SIT component. The reduction in the sterility rate highlights the importance of regularly monitoring the biological parameters of sterile males and the radiation source. Abstract: 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. Keywords: sterile insect technique; tsetse fly; sterility rate; competitiveness Insects 2022, 13, 476. https://doi.org/10.3390/insects13050476 https://www.mdpi.com/journal/insects