Pathogenicity of three formulations of Beauveria bassiana and efficacy of autoinoculation devices and sterile fruit fly males for dissemination of conidia for the control of Ceratitis capitata

This study reports the pathogenicity of three formulations of Beauveria bassiana (Balsamo) Vuillemin (Hypocreales) – Bb-ET, GHA, and Bb-AES – and their application in panel-type and cylinder-type autoinoculation devices, and using sterile males as vectors for the control of Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) in coffee-producing areas of the Central Highlands of Guatemala. Using sterile adults of C. capitata under laboratory bioassays, mean lethal concentrations (LC50) of 1.4 × 107, 2.4 × 106, and 8.2 × 105 conidia ml−1, and median survival times of 4.1 ± 0.1, 4.2 ± 0.1, and 3.8 ± 0.1 days, were recorded for the strains GHA, Bb-AES, and Bb-ET, respectively. These values indicate that the three strains were sufficiently pathogenic and that their period of biological activity was considered adequate for using sterile flies as vectors of the inoculum. Observed percentages of sporulated wild C. capitata flies were 57.3, 44.7, and 44.3% for sterile fly vectors, panel devices, and cylinder devices, respectively. The total population reduction at the end of the study period was over 90% for the three treatments. Our results show that sterile males used as vectors or disseminator devices may represent a new control method for area-wide integrated management of Mediterranean fruit flies. The potential of this new approach and its integration with other control methods, including the sterile insect technique, is discussed.