Efficacy of azithromycin in alternative chemical management of the fruit fly<i> Drosophila</i><i> melanogaster</i> (Meigen) (Diptera: Drosophilidae) reared on an artificial diet

This study evaluated the macrolide antibiotic azithromycin (AZR) as an alternative chemical for managing the model pest fruit fly Drosophila melanogaster (Meigen) (Diptera: Drosophilidae). The effects of AZR on survival rate, developmental time, adult longevity and larval cytochrome P450 monooxygenase (CYP450) activity of D. melanogaster were assessed at dietary concentrations of 100, 200, 400 and 800 mg/L. Dietary AZR significantly reduced survival at all developmental stages. At the highest concentration (800 mg/L), AZR significantly reduced adult emergence from 87.00 f 3.35 to 6.00 f 1.00 % (chi 2 = 112.511; d.f. = 1; P < 0.05) and increased developmental time to adulthood from 8.44 f 0.12 to 9.87 f 0.36 days (F = 3.566; d.f. = 4, 15; P < 0.05). Adult longevity was sharply reduced from 22.63 f 0.68 to 2.75 f 0.12 days (F = 172.020; d.f. = 4, 15; P < 0.05). However, AZR at 200-400 mg/L did not lead to a significant increase developmental time. In addition to decreased survival and prolonged developmental time in the 3rd instar, the highest AZR concentration significantly increased CYP450 enzyme activity in the larvae by approximately 7-fold (F = 795.256; df = 4, 15; P < 0.05). These findings suggest that antibiotic-based dietary formulation serve as promising alternative chemical management strategies for pest fruit flies, such as Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), as part of an integrated pest management program.