Fifteen freshly harvested and processed kolanuts were treated with 15 gram each of the plant material and arranged in batches of 5 kolanuts in each cup of the repellence chamber. The chamber was covered with plastic wheel cover and 50 freshly emerged weevils were introduced into it through the central tube fixed to the cover. After 24 hours, each chamber was opened and the number of weevils per cup (treated and control) were counted. Freshly harvested kolanuts were soaked in the plant extract filtrate for 6 hours and air dried for another 6 hours before storage in wicker basket lined with plantain leaves. Two hundred freshly emerged adult weevils were introduced into each basket. The number of dead weevil, fungal-infected kolanuts and kolanuts with weevil holes were counted every 2 days until 14 days post experimental period (DPEP). The fruit powder and ground fresh Capsicum longum repelled the weevils most with an average of 8 to 10 weevils found in the treated cups respectively. This was followed by Aframomum melegueta seed powder and Tetrapleura tetraptera fruit powder with a mean number of 11 weevils found in each treated cups. Capsicum longum, Tetrapleura tetraptera and Jatropha curcas caused significant mortalities of kolanut weevils (p > 0.05) by reducing the weevil population from 200 to 18, 19 and 30 respectively. There was significant difference (p > 0.05) in the number of weevil mortality ranging from 182 to 94 recorded in all the treated kolanuts when compared to the non-treated nuts with a mortality range of 28 to 4. The cumulative number of kolanuts with fungal infection was very low for both treated (2 to 22) and non-treated controls (2 to 6). This was a confirmation that the extracts are safe and do not facilitate the growth of moulds in stored products.
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