Seed-grade wheat with a moisture content of 13% to 14% was stored in "Transite" cylinders 8 inches in diameter and 40 inches long, each of which held 23 kg. of grain. Two hundred adults of Sitophilus granarius (L.) were added to the grain in each of two cylinders and allowed to wander freely. Two hundred adult weevils were added to 2.4 kg. of grain in each of two brass cloth cages, one of which was placed at the bottom of each of another pair of cylinders, which were then filled with grain. Another pair of cylinders filled with grain served as controls. The cylinders were kept at 25. and 65% to 70% relative humidity. Samples of wheat were withdrawn through side ports, with minimum disturbance to the bulk, after 2,4, and 6 months, and tested for moisture content, fungus population, germination, insect damage, and number of insects. Where insects were not confined, the moisture content increased to 20% in the upper portion of the grain; throughout the bulk, moisture content increased several per cent and storage fungi increased greatly. The greatest increase in temperature was approximately 6. (10.8.). Where insects were confined at the bottom of the column of grain, moisture content increased as much as 8% in the grain several inches above the infested portion and approximately 0.5% in the grain 1 to 2 feet above the infested portion. The grain in the controls remained essentially unchanged. Fumigation with a commercial formulation killed all the insects hut had no effect on the population of storage fungi which continued to increase after fumigation.
Document Type: Research Article
Publication date: June 1, 1960
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Journal of Economic Entomology is published bimonthly in February, April, June, August, October, and December. The journal publishes articles on the economic significance of insects and is divided into the following sections: apiculture & social insects; arthropods in relation to plant disease; forum; insecticide resistance and resistance management; ecotoxicology; biological and microbial control; ecology and behavior; sampling and biostatistics; household and structural insects; medical entomology; molecular entomology; veterinary entomology; forest entomology; horticultural entomology; field and forage crops, and small grains; stored-product; commodity treatment and quarantine entomology; and plant resistance. In addition to research papers, Journal of Economic Entomology publishes Letters to the Editor, interpretive articles in a Forum section, Short Communications, Rapid Communications, and Book Reviews.