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 craccivora)
It is a serious pest as a vector of virus diseases, such as the rosette virus disease, a major constraint to groundnut production, particularly in the dry season. The groundnut aphid is black or dark brown in colour, variable in size (1.5 to 2.0 mm long) with two black cornicles (horns at the rear of the body), and a black tail.
Early planting and dense close spacing are effective cultural practices.
Early planting allows plants to start flowering before aphids appear.
Dense planting provides a barrier to aphids penetrating in from field edges, discourages population build-up of aphids and reduces incidence of "rosette" disease.
- Monitor and observe build-up of aphids and of natural enemies.
- Conserve natural enemies. Ladybird beetles are reported as important natural enemies in groundnuts.
- Use neem seed or leaf extracts if necessary.
- Do not cultivate groundnut or other legumes continuously on the same ground.
- Use tolerant or resistent varieties. The groundnut variety "Nyanda" is reported to be tolerant to aphids.