ALTERNATIVE APPLICATION TO SYNTHETIC CHEMICAL PESTICIDE IN KOLA NUT PRODUCTION USING Mitragyna stipulosa AND Ataenidia conferta LEAF EXTRACTS

The kola nut weevils (Balanogastris kolae (Desbr) and Sophrorhinus spp) are the most destructive of all kola pests. Balanogastris kolae (Desbr) has been found to be the most destructive field to store pest capable of damaging 30-70% of stored nuts. As a result, farmers and traders use various synthetic pesticides such as alachor, DDT, aldrin and chlordane which have serious environmental and health impact on humans and also expensive. The research into natural plant extracts as cheap post-harvest pesticide with no serious deleterious effect on the environment has therefore become imperative. Acetone, petroleum ether and ethanolic extracts of Mitragyna stipulosa and Ataenidia conferta were analysed for their pesticidal activity. Petroleum ether extract of Mitragyna stipulosa gave the highest weevil reduction at a concentration of 100% when it was used to treat the kola nut seed for 24 hours. Mitragyna stipulosa extract showed moderately pesticidal potency with IC50 values < 50 μg/ml. Phytochemical screening of the extracts indicated the presence of terpenoids and steroids, saponins and tannins. The significant difference amongst the various extract treatment conclude that Mitragyna stipulosa appears to have the potentials to be used as alternative pesticide to kola farmers so as to reduce their total reliance on synthetic insecticides during production and storage.