Efficacy and Fate of Pirimiphos-Methyl Residue Applied at Two Dosage Rates to Wheat for Milling12

Abstract

Pirimiphos-methyl was applied to cleaned, hard winter wheat as a water emulsion at 7.3 and 14.6 ppm AI. Samples of the treated wheat were stored for periods up to 12 months to determine the relative effectiveness of residues in controlling adult rice weevils, Sitophilus oryzae (L.), lesser grain borers, Rhyzopertha dominica (F.), red flour beetles, Tribolium castaneum (Herbst), and confused flour beetles, T. confusum Jacquelin duVal. Residues were determined on the whole wheat and on milled fractions.