Pirimiphos-methyl and thiabendazole impact on the quality of on-farm stored shelled corn

A study was conducted to examine the ability of Actellic(R) (pirimiphos-met hyl, ICI Americas, Wilmington, DE), an organophosphorous insecticide, and M ertect(R) 340-F (thiabendazole, Merck and Co., Inc., Rahway, NJ), a benzimi dazole fungicide, to preserve the quality of shelled corn stored for an ext ended duration in metal grain bins. Treatments included application of piri miphos-methyl, thiabendazole, pirimiphos-methyl and thiabendazole combined, and untreated control. Corn samples of 0.3 liter were taken bi-monthly wit h 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 o f kernels with visible fungal growth. Suppression of insects and fungi by A ctellic or Mertect was evident, but the overall quality of the corn was not consistently improved by their application.