Efficacy of Azamethiphos for Grain and Surface Treatment Against Three Major Stored-Product Beetle Species

Abstract

The present study evaluated the insecticidal efficacy of a commercial formulation containing azamethiphos (Teenox® EC) against adults of the saw-toothed grain beetle, Oryzaephilus surinamensis, the lesser grain borer, Rhyzopertha dominica (F.), and the granary weevil, Sitophilus granarius (L.), under laboratory conditions. The azamethiphos formulation was assessed both as grain treatment on wheat and barley at 0, 2.5, 5, 10 and 20 ppm for all species, and as surface treatment on concrete and plastic surfaces at 0, 0.125, 0.25, 0.5 and 1 μg a.i./cm2 for O. surinamensis and R. dominica. In grain treatments, adult mortality increased significantly with concentration and exposure interval for all species. Mortality was generally higher in barley than in wheat, particularly after longer exposur