Preliminary screening of the larvicidal effect of Brevibacillus laterosporus strains against the blowfly Chrysomya megacephala (Fabricius, 1794) (Diptera: Calliphoridae)

Introduction: This study evaluated whether different strains of Brevibacillus laterosporus could be used to control larvae of the blowfly Chrysomya megacephala, a pest that affects both human and animal health. Methods: Mortality rates were recorded after 1-mL suspensions of sporulated cells of 14 different strains of B. laterosporus were added to 2.5g of premixed diet consisting of rotting ground beef fed to first instar larvae of C. megacephala. All bioassays were performed using 10 larvae per strain, with a minimum of three replicates for each bioassay. Larval mortality was recorded daily up to seven days. Results: Strains Bon 707, IGM 16-92, and Shi 3 showed the highest toxicity toward the larvae producing 70.5%, 64.5%, and 51.6% of larval mortality, respectively, which was significantly higher than that in the control group (p < 0.05). In contrast, strains NRS 1642, NRS 661, NRS 590 BL 856, NRS 342, ATCC 6457, Bon 712, and NRS 1247 showed limited or no pathogenic activity against the target larvae. Conclusions: Our preliminary data indicated that B. laterosporus could be used to develop bioinsecticides against C. megacephala.