Sound Detection of Stored-Product Insects That Feed Inside Kernels of Grain1

Abstract

A system for acoustically detecting internal-feeding insect larvae in grain is described. Larvae of the lesser grain borer, Rhyzopertha dominica (F.); rice weevil, Sitophilus oryzae (L.); and Angoumois grain moth, Sitotroga cerealella (Olivier), produced sounds loud enough to be detected 13-19 d after oviposition, depending upon the species. After first detection, larvae produced detectable sounds 71-90% of the time until pupation. Infestation rates could be estimated, at least in the range of 1-20 infested kernels per 100 ml of grain, where the infestation rate was strongly correlated to number of sounds as counted by a frequency counter.