Evaluating mortality and repellency potentials of Beauveria bassiana (Hypocreales: Cordycipitaceae) and Kosakonia radicincitans (Enterobacterialels: Enterobacteriaceae) on banana mealybug Pseudococcus elisae (Hemiptera: Pseudococcidae)

Mealybug causes sooty mould on banana leading to high rejection in international markets with significant economic losses, which was resolved using chlorpyriphos treated bags until 2019 when chlorpyriphos insecticide was banned. A field study demonstrated efficacy of biopesticides against mealybug infestation, but the mode of action was uncertain. This laboratory leaf-dip and topical bioassays were conducted to investigate mortality and repellency potentials of Beauveria bassiana fungus and Kosakonia radicincitans bacterium on mealybug Pseudococcus elisae Borchsenius (Hemiptera: Pseudococcidae). Treatments comprised biopesticides ( Beauveria and Kosakonia) , neem-based botanicals (Orgamix and Rata®), chemical insecticides (Pyriforce® –Chlopyriphos-ethyl, Calixine Super® – Acetamipride and Bifenthrine, Parastar® EC40 – Imidachlopride and Lambda-cyhalothrin), and control (tap water). For leaf-dip bioassay, mealybug mortality varied significantly ( P  < 0.05) after 72 h, with 100% for Calixine Super®, Rata® and Kosakonia , followed by 90% for Pyriforce®, Parastar® EC40 and Orgamix, and 70% for Beauveria . Significant ( P  < 0.05) variation in mealybug mortality also occurred for topical bioassay, with 100% for Pyriforce® and Beauveria , 91% for Calixine Super® and Parastar® EC40, and 73% for Orgamix. Mealybug survival analysis indicates comparable effect of biopesticides and botanicals with chemical insecticides but the latter was more hazardous. In no-choice trial, Calixine Super® and Rata® exerted 100% repellency followed by Beauveria (94%), Pyriforce®, Orgamix (88%) and Kosakonia (75%). Pyriforce (81%) showed highest repellency in choice trial, followed by Kosakonia (69%). Overall, Beauveria and Kosakonia demonstrated mortality and repellency potentials against mealybugs, with Kosakonia- induced mortality highlighting an important mode of action that was not previously reported, which can guide integrated pest management practices.