Effect of storage duration and storage technologies on pest infestations and post-harvest quality loss of stored sesame seeds in Ethiopia

Abstract

Sesame seeds, being a crucial traditional oilseed crop in Ethiopia, face challenges related to storage and insect pests that can adversely affect their quality and quantity. Farmers often sell their sesame seeds immediately after harvest at lower prices due to concerns about pest damage during storage. This study aimed to assess the impact of different storage containers and storage durations on reducing infestation by storage insect pests and minimizing losses of stored sesame seeds over a six-month period. The findings revealed that hermetic storage solutions, particularly PICS and SGP bags, effectively suppressed insect development, minimized losses, and maintained seed viability without the need for insecticides. Weight loss in PICS and SGP bags remained consistent regardless of the storage duration, whereas jute and PP bags exhibited a significant increase in weight loss. Lower seed germination rates were observed in PP and jute bags, whereas PICS and SGP bags maintained consistent germination rates throughout the storage period. PICS and SGP bags also exhibited a significant decrease in oxygen levels and an increase in carbon dioxide levels, contributing to the reduction in insect infestation. In comparison, traditional storage bags such as jute and PP bags exhibited higher insect counts, seed damage, and greater weight loss compared to hermetic bags. Therefore, hermetic storage solutions are recommended for farmers to minimize losses and preserve seed viability. During the study, three insect species were identified as the most prevalent in stored sesame seeds: Corcyra cephalonica, Tribolium spp (T. castaneum & T. confusum), and Rhyzopetha dominica. The maximum insect counts of these species were recorded in jute bags. At the beginning of the experiment, the average seed damage across all storage units was 1.9%, which increased to 14.1% in jute bags and 9.3% in PP bags after six months of storage.