INSECTICIDAL ACTIVITY OF PLANTS

This study aims to evaluate the insecticidal activity of some plants from the far north of Cameroon. Leaves and/or barks of four local plants (Azadirachta indica, Boswellia dalzeilii, Khaya senegalensis and Ocimum canum) were harvested, dried and ground into powder for the formulation of insecticidal sticks at different doses. Toxicity tests were carried out on adult Culicidae by fumigation. They revealed low mortality rates after 15 minutes of exposure. The persistence due to the smoke of the sticks leads to high mortality rates after 6 and 24 hours of exposure. Mortality rates increased with dose for each plant species. Lethal doses were calculated 6 hours after exposure for each plant powder. Azadirachta indica leaf powder was the most effective because it had the lowest LD50 value of 36.14%. These plant powders can be used as natural insecticides instead of chemical insecticides.