Towards biocontrol-based IPM for the diamondback moth in eastern and southern Africa

Effective chemical control of the diamondback moth (DBM), the key insect pest of crucifers in Eastern and Southern Africa, has become difficult. DBM has developed resistance to common insecticides and farmers increasingly use insecticide cocktails and spray more frequently. This is resulting in rising production costs, environmental contamination, health risks and high residues in produce. The recorded level of parasitism of indigenous parasitoids, including those of the genus Diadegma, is low compared with south-east Asia and South Africa. To enhance effective, economical and environmentally acceptable control of the pest, an IPM programme, based on the improved biological control of DBM, was initiated. This project tries to achieve improvements through a collaborative regional research effort in various steps: collection of basic information on distribution and efficiency of the indigenous natural enemy complex in Ethiopia, Kenya, Uganda and Tanzania; study of the taxonomy and bionomics of local parasitoids in comparison to parasitoids of proven value in south-east Asia and South Africa; importation, multiplication and release of superior parasitoids from Asia with support of the Asian Vegetable Research and Development Center (AVRDC) or South Africa. The organisational and operational set-up of the project is described.