U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska


Date of this Version



Biological Control 16, 88–90 (1999)


This document is a U.S. government work and is not subject to copyright in the United States.

Article ID bcon.1999.0733


Individual kernels of wheat containing immature rice weevils, Sitophilus oryzae (L.) (Coleoptera: Curculionidae), parasitized by Anisopteromalus calandrae (Howard) (Hymenoptera: Pteromalidae) could be separated from uninfested kernels and kernels that contained unparasitized weevils by using near-infrared (NIR) spectroscopy.Wheat kernels from cultures of the parasitoid were X-rayed and sorted into uninfested kernels, kernels infested with weevil larvae or pupae, kernels containing parasitoid larvae feeding on host weevils, and kernels containing parasitoid pupae and remains of the host. Kernels were automatically positioned and scanned (400–1700 nm) with the NIR system. Kernels containing parasitoid pupae were completely differentiated from kernels containing weevil pupae as well as all other kernels in this automated system. With the appropriate integration of NIR spectroscopy and seed-sorting instrumentation, kernels containing parasitoid pupae could be automatically collected from cultures of A. calandrae during the mass rearing of this beneficial insect.