Evaluation of biopesticides and insecticides against banana leaf and fruit scarring beetle nodostoma subcostatum jacoby in assam

Banana leaf and fruit scarring beetle Nodostoma subcostatum Jacoby is a key pest of banana in Assam causing significant reduction in fruit yield. Three biopesticides and two insecticides along with check chlorpyriphos 20EC were evaluated against this in vitro. The adult mortality was observed to be maximum in chlorpyriphos 20EC with LC₅₀ of (0.026, 0.015 and 0.010%) followed by profenophos 50EC (0.044, 0.029 and 0.018%), imidacloprid 17.8 SL (0.091, 0.059 and 0.052%), azadirachtin 0.05EC (0.135, 0.102 and 0.081%), Metarhizium anisopliae WP (30.335, 16.688 and 5.871) and Beauveria bassiana WP (37.157, 17.633 and 6.323%) after 1, 3 and 5 days of exposure, respectively. The order of toxicity with respect to LC₅₀ was chlorpyriphos > profenophos > imidacloprid > azadirachtin > M. anisopliae > B. bassiana for the exposure period of 1, 3 and 5 days.