Bioefficacy of Different Grain Admixtures Against Callosobruchus maculatus (Coleoptera: Bruchidae) Infesting Stored Cowpea Seeds as Grain Protectant.

The investigation on ‘Bioefficacy of different grain admixtures against Callosobruchus maculatus (Coleoptera: Bruchidae) infesting stored cowpea seeds as grain protectant’ was carried out at College of Agriculture Dapoli, Ratnagiri (M.S.). Results revealed that, the treatment of Vekhand powder observed to be more effective, in which only 50 per cent eggs were hatched. Whereas, Ghaneri leaf powder failed to prevent egg hatching in which 100 per cent eggs were hatched. The mean number of eggs laid by C. maculatus within the treatments varied in between 9.67 to 385.33. The total developmental period was ranged from 24.30 to 28.42 days in various treatments of grain admixture. The maximum period of 28.42 days was observed in Black pepper. Whereas, mean number of adult emerged was significantly lower in all treatments as compared to untreated control (238.67). The maximum adult longevity of 10.30 days was recorded in untreated control while minimum in Black pepper (4.10 days) followed by Vekhand powder (4.20 days). The treatments with Vekhand powder, Black pepper and Ash having 2.33, 4.33 and 6.00 per cent grain infestation, respectively and were recorded most promising giving maximum protection to the cowpea grains. Per cent weight loss by C. maculatus in cowpea grains revealed that the untreated control recorded maximum weight loss (30.89 per cent). The overall result concluded that the treatment of Vekhand powder was the best surface protectant followed by Black pepper powder and Ash for Cowpea seed against pulse beetle.