Incidence and Storage-related Infestation of Callosobruchus chinensis (L.) in Stored Bengal Gram: Insights from Major Growing Districts of West Bengal, India

Abstract

Field surveys were conducted in the year 2021–22 to assess the infestation of the pulse beetle, Callosobruchus chinensis L., in farmer-stored Bengal gram seeds across Birbhum and Murshidabad districts of West Bengal. Five blocks from each district were selected, with five farmers surveyed per block, totaling 100 seed samples. Parameters assessed included moisture content, seed damage, and storage methods. Average moisture content and seed damage were 11.86% and 3.66% in Birbhum and 12.09% and 3.69% in Murshidabad. Rampurhat-II (Birbhum) and Suti-I (Murshidabad) showed the highest moisture and seed damage, while Suri-II (Birbhum) and Raghunathganj-I (Murshidabad) recorded the lowest. Infestation was strongly correlated with moisture: only 12.5% of samples with less than 10% moisture were infested, rising to 100% in those with more than 13%. Plastic bags (40%) were the most used storage method, followed by drums, metal bins, gunny bags, loose storage, and earthen pots. Metal bins had the lowest infestation (11.11%), while earthen pots had the highest (100%). No storage structure was entirely pest-free, underscoring the urgent need for improved post-harvest storage practices.