Main aphids in Africa: Black bean aphid ([i]Aphis fabae[/i]), Cabbage aphid ([i]Brevycoryne brassicae/Myzus persicae[/i]), Groundnut aphid ([i]A.craccivora[/i]), Cotton aphid ([i]A.gossypii[/i]), Russian wheat aphid ([i]Diuraphis noxia[/i]), Cypress aphid ([i]Cinara cupressi[/i])
Aphids (Aphis gossypii)
Aphids are found in groups on the under surface of young leaves. When numbers increase they can move to upper leaf surfaces, stems and flowers. Aphids, in particular the cotton aphid, can become important pests in the cool dry season.
- Spray neem products. They have a repellent effect and have been effective in reducing numbers of the cotton aphid on eggplants. Effective treatments included foliar sprays with aqueous extracts of neem seeds, kernel and neem cake at concentrations of 10 to 50 g/l, and 3% neem oil applied at 10 days intervals. Bare root dipping with 50g/l aqueous neem kernel seed extract, 3% neem oil and a 10 g/l aqueous neem cake extract have also been effective (Ostermann & Dreyer,1995).