Biological control of Helicoverpa armigera in Africa.
Abstract
Natural enemy complexes of the African bollworm (Helicoverpa armigera) are discussed, experiences with microbial control are summarized, and the prospects for classical, inundative and augmentative biological control (BC) are examined. It is shown that there are rich and varied indigenous natural enemy complexes attacking H. armigera in southern and East Africa. A total of 83 identified and 93 partially identified species of parasitoids, mostly in the families Ichneumonidae, Braconidae and Tachinidae, have been recorded. Predator records from Africa include Anthocoridae, Reduviidae, Carabidae, Staphylinidae, Coccinellidae, Sphecidae, and Formicidae. These natural enemies vary geographically, temporally and in their host-plant associations. The situation is complicated, as generalist predators tend to be more important than parasitoids. The various BC methods have generally failed to achieve substantial or permanent gains in control. With high-value crops such as cotton, these approaches alone seem inadequate. Recent developments in participatory integrated pest management and action research in the region suggest ways in which research findings can be adopted and expanded by farmer communities. In addition, the advent of Bt-transgenic plant varieties to Africa offers the promise of reduced insecticide inputs.
Citation
Cherry, A.; Cock, M.J.W.; Van den Berg, H.; Kfir, R. Biological control of Helicoverpa armigera in Africa. In: Neuenschwander, P.; Borgemeister, C.; Langewald, J. (Eds) Biological Control in IPM Systems in Africa. CAB International, Wallingford, UK (2003) 329-346. ISBN 0-85199-639-6