Ecofriendly management of banana leaf and fruit scarring beetle Basilepta subcostatum jacoby (Coleoptera: Chrysomelidae)

An experiment was conducted during 2010–11 at Horticulture Experimental Farm, Assam Agricultural University, Jorhat to test the field efficacy of biopesticide (azadirachtin 0.15%), biocontrol agent (Beauveria bassiana, 1X 10⁷ conidia/ml), chemical pesticide (carbaryl 0.3%), cultural practices (tilling and clean cultivation, bunch covering with plastic bag) and some combination of cultural and botanical treatments (tilling and clean cultivation + azadirachtin 0.15%), and azadirachtin 0.15% spray + bunch covering) against banana leaf and fruit scarring beetle. Observation on beetles, number of scars on leaf and fruit, finger characters (pulp-skin ratio and finger weight) and yield were recorded. The best results were obtained for reduction in damage from carbaryl 0.3% spray which was followed by azadirachtin 0.15% spray with bunch covering, tilling and clean cultivation with azadirachtin 0.15% spray, bunch covering with plastic bag, tilling and clean cultivation, azadirachtin 0.15% spray and Beauveria bassiana suspension spray. Fruit infestation was recorded lowest in azadirachtin 0.15% spray with bunch covering. The highest yield of 45.16 tonnes/ha was recorded in azadirachtin 0.15% spray with bunch covering.