Incidence of Apion amplum (Faust) (Apionidae : Coleoptera) on greengram with its biopesticidal management

A field experiment was conducted during kharif season of 2008-09 at Main Research Station, University of Agricultural Sciences, Dharwad. Seed weevil, Apion amplum (Faust) (Apionidae : Coleoptera) has gained a major pest status on greengram and blackgram in recent years. The incidence studies revealed that A. amplum (Faust) was in peak activity on the crop sown in first fortnight of July and recorded the highest mean numbers of weevils (4.57 and 4.70/plant) followed by second fortnight of July. Evaluation of different biopesticides revealed that the application of Bacillus thuringiensis (Sandiego) @ 1 ml/l recorded cent per cent mortality compared to other biopesticides after 11 days of observation under laboratory condition. In field also, B. thuringiensis was found superior in reducing mean weevil numbers, pod and seed damage to greengram and recorded highest yield over other biopesticides.