Vitex doniana is a medium sized deciduous tree of 8 to 18m high, with a heavy rounded crown and a clear pole up to 5m in height. The study evaluated the insecticidal efficacy of Vitex doniana extract on spodoptera litoralis using bark and leaves. The plants parts were collected from Abubakar Tafawa Balewa University Bauchi. Samples were left to dry by air under normal conditions in laboratory for two weeks. The dried samples were grinded into powder using a blender. The powder was then extracted using 350% ethanol by cold maceration. The culture of Spodoptera littoralis was maintained in the laboratory on cabbage and corn leaves for the insect to acclimatize to the environment. The phytochemicals found in the extract were alkaloids, glycosides, flavonoids, saponins, tannins, steroids and terpenoids. The study revealed that the crude ethanolic extract of leaves at 400mg concentration was more effective against the seventh larva stage than that of the bark at the same concentration with average mortality rate of 6.08%, compared to 4.08% for the bark. Hence, the use of Vitex doniana leaves as an insecticide for the control of spodoptera littoralis is safe and environmental friendly compared to the synthetic insecticides which is hazardous and it residual effect is persistence in the environment.
Key words: Vitex doniana, Spodoptera litoralis and insecticidal.
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