Pirimiphos-Methyl and Thiabendazole Impact on the Quality of On-Farm Stored Shelled Corn

A study was conducted to examine the ability of Actellic^® (pirimiphos-methyl, ICI Americas, Wilmington, DE), an organophosphorous insecticide, and Mertect^® 340-F (thiabendazole, Merck and Co., Inc., Rahway, NJ), a benzimidazole fungicide, to preserve the quality of shelled corn stored for an extended duration in metal grain bins. Treatments included application of pirimiphos-methyl, thiabendazole, pirimiphos-methyl and thiabendazole combined, and untreated control. Corn samples of 0.3 liter were taken bi-monthly with a deep-bin cup probe and kept frozen until processed. Quality parameters examined included total insect contaminants (numbers of insects and insect fragments), numbers of insect-damaged kernels, percent fines, and numbers of kernels with visible fungal growth. Suppression of insects and fungi by Actellic or Mertect was evident, but the overall quality of the corn was not consistently improved by their application.