The desert locust

International Institute of Tropical Agriculture

Locust swarms are threatening crops across a vast area of Africa. The last time major swarms affected the region — in 1988 — it took US$300 million and 1.5 million litres of chemical pesticides to control the threat. Since then, concerns about the risks of such pesticides to human health and the environment have led to calls for alternative approaches.

Although researchers have since developed a biological pesticide based on fungal spores, it has yet to be widely used, largely because of regulatory hurdles and the belief that biological control is not a valid alternative to chemical pesticides. In this article in Nature, however, Peter Neuenschwander, of the International Institute of Tropical Agriculture, argues that biological control can be a safe, sustainable and economically viable alternative.

By releasing 'natural enemies' of crop pests in Africa, researchers have in some cases reduced crop losses caused by pests by 80 to 95 per cent. Other biological pest control methods include releasing viruses or bacteria that affect specific insect pests, and careful use of insecticidal plant extracts. Safer pest control is possible, says Neuenschwander, but its implementation will require political will and support from the donor community.

Link to full article in Nature

Reference: Nature 432, 801 (2004)