Approximately 20 years after the accidental introduction of the larger grain borer (Prostephanus truncatus [Horn] [Coleoptera: Bostrichidae]) to Africa our understanding of the biology and ecology of this pest has considerably improved and our knowledge of the impact of its natural enemy, the histerid predator Teretriosoma nigrescens Lewis, has substantially increased.

This meeting is the fourth Africa-wide forum on post-harvest issues, with particular reference to the larger grain borer. The initial meeting was held in Arusha, Tanzania, in 1988 and focused mainly on containment strategies for the pest. During the subsequent meeting in Cotonou, Benin, in 1989 the prospects of biological control were discussed. One year later in Lomé, Togo, initial steps for the implementation of biological control of the larger grain borer were presented. Since the Lomé meeting, considerable success has been recorded in biological and integrated control of the larger grain borer both in West and East Africa. Some of these results had already been reported in Naivasha, Kenya, in 1996 at a regional meeting on on-farm storage pests in East and Central Africa. However, the present meeting offered the first opportunity to discuss and summarize recent research and implementation results with representatives from most of the affected countries. The meeting brought together many international stakeholders such as FAO, GTZ, IIBC, DANIDA, IITA as well as scientists, plant protection specialists and extension officers from 17 African countries.

During the last 20 years of intense research and implementation in post-harvest, a participatory IPM approach has been widely accepted. Moreover, in recent years a more holistic view of the post-harvest sector has been proposed. Within such a system, stored product protection is treated as one aspect, though an important one in the chain, starting at harvest and ending with the purchase of the produce by the consumer. A methodological framework to identify the crucial bottlenecks in post-harvest systems, jointly developed by FAO and GTZ, has been successfully tested on a variety of commodities including maize. The ultimate aim of such a systems approach is to focus post-harvest interventions less on the commodity itself and more on the actors, such as farmers, traders, processors and consumers.

The strategy of the present meeting was bi-faceted. Recent results on biological and integrated control of post-harvest pests with particular reference to the larger grain borer were presented. Moreover, stored product protection in on-farm maize was no longer dealt with as an isolated field of research and implementation, but as part of the maize post-harvest chain.

It is always difficult for editors of such proceedings to summarise the contributions and recommendations made. However, we believe that most of the participants were convinced of the impact of biological control of the larger grain borer within the framework of IPM in stored maize. In addition, great interest for a systems approach in post-harvest was expressed. We hope that these proceedings, like the ones from Arusha, Cotonou, Lomé and Naivasha, will contribute to a better understanding of post-harvest problems encountered in maize production in Africa.

Cotonou, December 1997