Insecticidal Activity of Bacillus cereus against the Spotted Wing Drosophila

Abstract

Drosophila suzukii (D. suzukii) is a notorious pest that causes devastating damage to thin-skinned fruits because female flies use a serrated ovipositor to pierce the skin of ripening fruits and lay eggs in the flesh with a serrated ovipositor. The current application of insecticides to manage this pest has led to serious resistance and environmental hazards, so there is an urgent need for alternative strategies. In the present work, we reported that identifying a potential entomopathogen Bacillus cereus H1 (B. cereus H1) for D. suzukii from their habitat was lethal to D. suzukii adults following ingestion. First, we isolated and identified an entomopathogen B. cereus H1 from D. suzukii morbid pupae. Next, B. cereus H1 robustly arrested the development of the fly progeny. Moreover, B. cereus H1 exerted an adverse effect on the survival and locomotion of adult flies. Mechanistically, B. cereus H1 disrupted intestinal homeostasis and triggered oxidative innate immunity, resulting in death within 5 days. To the best of our understanding, this study is the first to investigate the role of B. cereus H1 in managing D. suzukii, suggesting that it could be suitable for candidate biopesticides of D. suzukii. Future studies that exploit the mechanism underlying the pathogenicity of B. cereus H1 toward the Spotted Wing Drosophila would improve the knowledge of the ecology of host-entomopathogen interactions in nature.