Malathion deposits of about 11, 17, and 20 ppm protected rough rice for 6 to 12 months under Gulf Coast environmental conditions. Protection lasted slightly longer in bin tests than in jar tests. Residues on rough rice greater than 8, 4, and 2 ppm were required to control confused flour beetles, Tribolium confusum Jacquelin duVal; lesser grain borers, Rhyzopertha dominica (F.); and rice weevils, Sitophilus oryzae (L.), respectively. Initial deposits on rough rice were 20 ppm; deposits decreased to levels below 8 ppm within 3 months. Initial deposits on hulls were 80 ppm; deposits did not fall below 8 ppm for 7 to 11 months. Residues on bran and milled rice increased for 3 months and then declined. Residues on bran reached a maximum of 30 ppm but fell below 8 ppm in 6 to 10 months; on milled rice. maximum residue was 0.32 ppm. Varieties of bran and milled rice retained malathion in the following order: 'Belle Patna' > 'Nato' > 'Dawn.' This ranking apparently was dependent upon the relative surface area and the thickness of the covering hull on kernels of each variety.
Document Type: Research Article
Publication date: October 15, 1971
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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.