Biological pest control is an important tool in stored products protection. To improve the biological control of the granary weevil Sitophilus granarius L. (Coleoptera: Curculionidae), a rearing box for the parasitic wasp Lariophagus distinguendus (Förster) (Hymenoptera: Pteromalidae) has been developed. The box contains breeding substrate as well as populations of hosts and parasitoids and is placed directly in the storage site. A special outlet prevents hosts from leaving the box while freshly emerged parasitoids are released continuously over several months. A repeated shipment of wasps has thereby become obsolete
