(Sitophilus granarius)
Biology:
The grain weevil is a 3 to 5 mm long, unicolored reddish-brown to blackish-brown weevil, depending on its age. It is unable to fly and lives primarily in grain stores, where it feeds on all types of grain. To lay eggs, the female eats a hole in a grain, lays the egg inside and then seals the opening with a plug of secretion. The entire development from egg to larva to pupa takes place invisibly in the grain. It is almost completely eaten out.
The animals are relatively tolerant of the cold and can also overwinter in an unheated attic.
Damage:
The grain weevil is one of the most common primary pests of cereals worldwide, i.e. it can also attack whole grains, while many other beetle species are dependent on cereals with a broken part.
In countries with a temperate climate, the grain weevil is the most important pest in stored grain. Infested grain heats up, becomes musty and secondary pests such as bacteria, fungi and mites colonize.
In addition to the damage caused by the larvae, the enormous reproduction rate of the beetles primarily results in losses because the infested produce is no longer marketable and is lost.
