The potential use of biological control of pests in stored grain

International data suggests that there are a number of approaches to the biological control of pests in stored grain that could be applied in the UK. These would include the addition of predatory insects and mites, and the use of some microbial agents which cause disease in pest species. However, there are only limited data on the use of biocontrol under commercial conditions and no data that would give complete confidence that procedures used elsewhere would be effective in this country. The most promising agents would not appear to offer any toxic risks to the consumer and only very limited risk to the user.

The world-wide research programme on the biocontrol of pests in stored grain is very small and fragmented. Currently, there is very little research on this topic applicable to European conditions within the UK or any EC Member States.

The storers and end-users of grain in the UK do not seem to have major concerns about current pest control practices. Whilst the idea of biocontrol is not dismissed out of hand by storekeepers, they would only be seriously interested if there were major changes in the availability of current measures or biocontrol was equally effective and less expensive than current methods. End-users are against the addition of biocontrol agents to grain on the grounds that this would constitute contamination.

Protozoa, fungi, bacteria and viruses that might be used as biocontrol agents would require registration under the Control of Pesticides Regulations. This is an expensive process and is likely to limit the interest of producers. Conversely, predatory or parasitic insects, mites and nematodes would not require registration and so could be offered for sale at minimum cost on the part of the supplier. It therefore seems likely that, in the short term, any future development of biocontrol for grain pests in the UK will come from the use of predators or parasitoids.