Aktivitas Larvasida Beauveria bassiana Hasil Passage melalui Tenebrio molitor terhadap Larva Aedes aegypti dan Culex quinquefasciatus

Abstract

Dengue and lymphatic filariasis remain major mosquito-borne public health problems. Repeated use of chemical larvicides may select resistant vector populations and raises concerns regarding environmental safety. Beauveria bassiana is an entomopathogenic fungus with potential for biological control; however, prolonged in vitro maintenance may alter its pathogenicity. This laboratory experiment assessed Beauveria bassiana after passage through Tenebrio molitor against third-instar Aedes aegypti  and Culex quinquefasciatus larvae. Passage-derived conidial suspensions at 1 × 10⁶, 1 × 10⁸, and 1 × 10¹⁰ spores/mL were tested in three replicates of 30 larvae each. Cumulative mortality was recorded daily for seven days and analyzed by one-way analysis of variance followed by Tukey’s honestly significant difference test at the 5% level. Lethal times were estimated from the time–mortality relationship. On day 7, mortality reached 98.89% at 1 × 10¹⁰ spores/mL in both species. The shortest LT50 was 4.91 days in Ae. aegypti and 3.90 days in Cx. quinquefasciatus . Differences among treatments were detected from day 1 in Ae. aegypti and from day 3 in Cx. quinquefasciatus . Higher conidial concentrations were associated with greater mortality and shorter lethal times. These findings demonstrate the larvicidal activity of passage-derived B. bassiana. Nevertheless, the specific effect of passage cannot be distinguished from the concentration effect without matched non-passaged comparators at all concentrations.