Hermetic Storage as a Chemical-Free Alternative for Millet Preservation in Niger

Millet (Pennisetum glaucum (L.) R. Br.) is the most widely consumed cereal in Niger. Although its production lasts six months, consumption is year-round, requiring effective and safe storage solutions. Post-harvest losses of millet can reach up to 17% after several months of storage. Chemical pesticides are commonly used in large warehouses, but concerns over misuse and health risks have driven interest in safer alternatives. This study assessed the effectiveness of traditional and improved storage methods in controlling Trogoderma granarium Everts, an emerging pest of millet in large warehouse facilities. Three storage methods were tested: (i) a hermetic Purdue Improved Crop Storage (PICS) bag; (ii) chemical pesticide Phostoxin; and (iii) an untreated ordinary polypropylene bag as a control. Naturally infested millet obtained from a large warehouse was assessed for each treatment at the start and end of a six-month storage period. Two insect pests were identified, T. granarium and Tribolium sp. Initial infestation levels were 60 larvae and 0.47 adults per 500 g. After six months, the control showed a 1.7-fold increase in T. granarium larvae, a 2.96-fold increase in its adults, and a 3.19-fold increase in Tribolium sp. adults, resulting in 19.15% weight loss. In contrast, PICS and Phostoxin treatments maintained initial pest levels with no weight loss. These results suggest that hermetic storage is a safe, effective, and chemical-free alternative for preserving millet in large warehouses.