Abstract

Quality seed is an important resource for any seed-propagated crop. Cowpea (Vigna unguiculata) seed is prone to cowpea weevil (Callosobruchus maculatus) infestation during storage. This can result in 100% seed loss when stored without treatment. Smallholder farmers in Kenya use traditional methods of storage and occasionally accompanied by pesticides treatment. Due to health concerns, pesticide use is discouraged. Therefore, this study was conducted to determine effectiveness of packaging materials on reducing cowpea weevil damage during seed storage. A repeated experiment was carried out at the entomology laboratory using a single cowpea line each time. Packaging materials evaluated were; cellulose paper bags, gourds, grain storage bags, polyethylene bags and glass bottles. Completely randomized design was used and each treatment was replicated thrice. Data were obtained on number of seeds with holes, mean number of holes per seed, seed weight loss, damage score, and seed germination. Quantitative data were subjected to ANOVA and correlation analysis. Glass bottles, polyethylene bags, and hermetic grain storage bags showed significantly less seed damage than gourd and cellulose bags in all the parameters tested except germination (p≤0.05). The parameters used to evaluate damage were positively correlated except germination. Only seed stored in glass bottles showed high germination rates; whereas, germination rates were generally less than 50% for the other seed packaging materials. Glass bottles were ranked the best packaging material, followed by polyethylene bags and grain storage bags respectively. Hermetic seed packaging was effective in reducing weevil damage and preserving seed quality.

Key words: Callosobruchus maculatus, seed quality, hermetic seed storage, smallholder growers.