Potential for using indigenous plant-derived products as protectants against insect pests of stored grain on small farms in Africa

africa afrique azadirachta indica azadirachtin azadirachtine biological control cereales cereals chrysanthemum cinerariaefolium control de plagas extractos del piretro grain granos insecte nuisible lutte antiravageur lutte biologique perte au stockage pest control pest insects petite exploitation agricole prostephanus truncatus pyrethrum extracts sitophilus zeamais small farms storage losses