Stored-Grain Insect Control Studies With Radio-Frequency Energy1

Abstract

Exposures of the rice weevil, Sitopophilus oryzae (L.); granary weevil, S. granarius (L.); Trogoderma parabile Beal; T. glabrum (Herbst); saw-toothed grain bettle, Oryzaephilus surinamensis (L.); cadelle, Tenebroides mauritanicus (L.); Indian-meal moth, Plodia interpunctella (F.), to 39-megacycle radio-frequency (rf) electric fields in wheat can be lethal to all stages of insects tested. High field intensities are more efficient for control than low intensities. Exposures required for complete mortality and the amount of delayed mortality vary among species and developmental stages. Efficiency of rf insect control appears to increase with increasing moisture content of the host grain from 12 to 16% moisture. Rf treatment of wheat prior to infestation does not influence development of subsequent infestation by granary weevils. Mild rf treatment of egg stages increases subsequent adult emergence for several stored-grain insect species. Estimated costs of rf insect control exceed those of chemical methods. Improvements in efficiency of treatment and dual use of equipment for benefit treatment of seed could improve prospects for practical application.