Laboratory evaluation of diatomaceous earth deposits mined from several locations in central and southeastern Europe as potential protectants against coleopteran grain pests

► Diatomaceous earths (DEs) varied in their efficacy as protectants against infestation by coleopteran grain pests. ► Geographical origin had an impact on the efficacy of their application method. ► DEs which were more effective as grain protectans proved to be less effective for surface treatment, and vice versa. ► Central and southeastern Europe are sources of raw DEs for grain protectant formulations. ► Besides geographical origin, the efficacy of the tested DE samples depended upon species, commodity, temperature and RH. ► The tested DEs were more effective when applied as dusts rather than slurries.