Insects are responsible for the most important qualitative and quantitative losses of stored cereals. Significant attacks can cause temperature and humidity to increase, also causing the possibility of fungal attack (with mycotoxin production). Many foodstuff processors and exporters require absolutely insect-free cereals in order to be able to be put on sale or used for processing and/or seed production.
The stored foodstuffs are easy targets for tiny pests, usually Coleoptera, but also Lepidoptera and Diptera. These insects are often already present in the storage environment before the arrival of the raw material, in other cases they may come directly with the already colonised raw material or enter subsequently through the openings in the warehouse. They can often be detriticola species that can cause serious damage to grain, both quantitative and qualitative.
Through trade, the risk of spreading pests has become overt, so much so as to impose strict incoming inspections of the raw material before storage. It is also true that, currently, many pests are now ubiquitous, so a seasonal control plan is to be considered mandatory. The favourable microclimate in storage environments and the speed of insect development contribute to bringing about a rapid and widespread attack on the foodstuffs that can, in a short time, spread to products already packed and ready to be sold.
Among the harmful Coleoptera are the Palm Weevil (Sitophilus spp.), the Lesser Grain Borer (Rhyzopertha dominica), the Sawtoothed Grain Beetle (Oryzaephilus surinamensis) and the various Anobiids (bread and tobacco weevil). These insects directly attack the kernel or the packaging and can be found in warehouses, pasta factories and rice mills. With reference to the order of Lepidoptera, the flying at dusk of butterflies commonly called Moths is frequent.