Reducing grain storage losses in developing countries

We investigated the use of insecticide-treated material and modified atmosphere storage for reducing insect damage in stored maize. Results showed that insecticide-treated netting and insecticide-treated seed bags protected grain from insect damage, with the treated seed bags protecting grain for up to nine months if the grain was free from insects before storing. Covering the opening of grain storage containers with treated netting provided good control of stored-grain insects and may offer additional protection for grain silos being promoted in developing countries. Neither treated bags nor netting provided control if the grain contained insects before storage, thus emphasising the need to provide some means of controlling initial infestations at the time of storage when using bags or netting. We also showed that good control of insects can be achieved if the grain is stored in air-tight rigid containers that cannot be penetrated by insects or rodents. Hermetic plastic bags were readily penetrated by insects and rodents, thus negating their ability to protect grain from insects. We also showed that reducing oxygen levels through the use of a candle in stored environments does little to protect grain from insects. Modifying the atmosphere by reducing oxygen levels or raising carbon dioxide levels also provided good control of stored-grain pests. The solutions outlined in this paper offer farmers in developing countries methods to protect grain from stored-grain insects, thus reducing losses and improving food security.