Hexane (non-polar), chloroform (partial polar), distilled water, methanol, acetone and ethanol (polar) extracts (from 10, 20 and 30g/100ml extraction levels) and leaf powder of Millettia ferruginea were tested as protectant against maize weevils on filter paper and in maize grains under laboratory condition. These were applied at the rate of 2 and 3 ml in filter paper and at a rate of 5, 10 and 15% (w/w) on admixture bioassays. Parental adultâ€™s mortality, F1 progeny emergence, percent protection, grain damage and weight loss was the parameters measured. Polar solvent extracts of the M. ferruginea applied at all rates from all levels extraction induced significant (p<0.05) toxicity effect compared to non-polar and partial solvent extracts, as well as the negative controls. Besides, 100% adult weevilâ€™s mortality was induced by ethanol and acetone extracts of M. ferruginea applied at the rate of 3 ml per filter paper from 30 g/100ml level of extraction 24 h after treatment application. Furthermore, the powder of M. ferruginea applied at all rates also induced good degree of protection of maize grains ( â‰¥ 73%) against F1 progeny emergence, percent grain damage (â‰¤4.33) and weight loss (â‰¤ .58) by maize weevils in about 2 months storage period. Therefore, leaf powder and the solvent extracts of M. ferruginea can be used for managing maize weevils on stored maize under farmerâ€™s storage conditions in Ethiopia.
Keywords: Millettia ferruginea, Sitophilus zeamais, botanicals, storage insect pests, food security