Diversity of Stored Grain Pests in North 24 Parganas & Kolkata Districts, West Bengal, India & Their Management by Organic Pesticides

Stored grains or pantry commodities are ravaged by a number of insect pests to meet their nutritional and shelter needs, resulting in both qualitative and quantitative losses. The favourable climatic conditions in India allow these pests to thrive year-round. These insects not only damage but also contaminate food items with their excrement and unpleasant odours, rendering them unfit for consumption and posing significant health risks. Consequently, post-harvest losses in India account for approximately 10% of total grain and 9.5% of total pulses. From the present study during August 2024 to February 2025, eight (8) insect species belonging to two (2) orders namely Coleoptera (87.5%) and Lepidoptera (12.5%) were recorded on stored grains, the prime groups of insects responsible for the post-harvest loss with order Coleoptera being the most dominant group. Out of eight (8) collected, five (5) insects (63%) were reported to be internal feeders while only 3 insects (37%) were recorded as external feeders. Sitophilus oryae Linnaeus was the predominant stored grain pest noticed to attack most of the grain varieties. This research represents the inaugural documentation of insect pests associated with stored grains in North 24 Parganas and Kolkata districts of West Bengal. Our extensive research emphasizes the use of biopesticides (essential oils) as an alternative to traditional methods for the management of stored grain pests. To enhance effectiveness, we suggest employing solid absorbent granules infused with essential oil, which should be placed in perforated cloth bags placed in containers located in kitchens, stores, and warehouses. This method is expected to yield improved results within minutes to hours, leading to the elimination of pests.