Cashew kernels were extracted with six different solvents namely methanol, ethanol, water, acetone, pet-ether and n-hexane. The different extraction products were evaluated on C. maculatus adults for their mortality, ovicidal and adult emergence effects. The long-term protectant ability of the cashew kernel extracts and water absorption capacity of the treated cowpea seeds were also investigated. The results obtained showed that the steam distillate was most toxic to C. maculatus. The least toxic extracts on the insect were those of methanol and ethanol. The extracts drastically reduced oviposition in C. maculatus. The cowpea seeds treated with steam distillate had the lowest water absorption capacity, while the highest water absorption capacity was obtained in grains treated with ethanol and methanol. At 2.0% v/w cashew kernel extracts, the percentage water absorption capacity of cowpea seeds increased with increase in the interval of submergence.Steam distillate and the extracts of n-hexane, pet-ether and acetone completely prevented infestation and damage of the treated cowpea seeds for a period of three months as there was neither weight loss nor damage in the treated grains. In the grains treated with the methanol and ethanol extracts, damage of 20.17% and 9.76% were recorded, respectively. The results obtained from this study revealed that extract of cashew kernel is effective in controlling cowpea storage bruchid, C. maculatus and could serve as an alternative to synthetic insecticides for the protection of stored cowpeas against bruchids.

Cowpeas stored in a hermetic container, jute bag and nitrogen atmosphere at ambient (temperature 21-31"C, relative humidity 72-86%) for 6 months were evaluated for changes in proximate composition, nutritional and sensory qualities when cooked by different methods. Nitrogen storage effectively preserved the chemical composition of the cowpeas and maintained grain with better cooking characteristics than cowpeas stored in other systems. Cooking methods and the storage conditions influenced the cooking time and significantly affected the thiamine loss, rate of proteolysis, in-vitro protein digestibility and sensory qualities of the cowpeas. Cooking the stored unsoaked cowpeas with local rock salt to reduce cooking time had a deleterious effect on both the nutritional and sensory qualities of cowpeas.

Callosobruchus maculatus is the most damaging insect pest of stored cowpea (Vigna unguiculata) seeds in Nigeria. Thus, this present research work was put in place to assess the insecticidal activities of the extracts obtained from the leaf and stem bark of Kigelia africana (Lam.) Benth against the cowpea seed beetle, C. maculatus. The parameters that were assessed were adult mortality, oviposition and adult emergence of C. maculatus. The experiments were conducted under laboratory conditions of 28AE2 C temperature and 75 AE 5% relative humidity. The extracts were applied at dosages of 0.3, 0.6, 0.9 and 1.2 mL per 20 g of cowpea seeds. The two extracts of K. africana were found to be toxic to the survival of the C. maculatus. However, the extract obtained from the leaf was more potent to the beetle than the extract obtained from the stem bark of the same plant. The two extracts also reduced ovipositipon and completely suppressed adult emergence at the highest dose of 1.2 mL per 50 g of cowpea seeds. The results obtained in the present research work showed that the two extracts of K. africana were effective in suppressing the population of the infamous stored pest of cowpea seed beetle, C. maculatus and could therefore be recommended to replace the harmful synthetic chemical insecticides in protecting cowpea seeds in storage.

The test plants species, namely Crotaria retusa, Hyptis suaveolens, Ricinus communis and Tithonia diversifolia were extracted with water. The extracts were evaluated on Callosobruchus maculatus for mortality, oviposition and adult emergence effects. The long-term protectant ability and viability were also investigated. The results showed that the aqueous extracts from T. diversifolia were most effective on C. maculatus, followed by extract from Ricinus communis. The least potent extracts were those extracted from Crotalaria retusa and Hyptis suaveolens. Also, the extracts considerably reduced oviposition by C. maculatus. Extracts from T. diversifolia and R. communis drastically reduced infestation and subsequence damage of the treated cowpea seeds for a period of three months. Most of the treated seeds germinated after 90 days storage period. The results from this study revealed that aqueous extracts from all the four plants species were effective in controlling cowpea bruchid, C. maculatus and could serve as an alternative to synthetic insecticides for protection of stored cowpea seeds against bruchids.

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