The persistence of phorate and its 5 oxidative analogues in soil was determined with thin-layer chromatography, gas-liquid chromatography, and insect bioassay. Phorate and its oxygen analogue were rapidly oxidized to their respective sulfoxides and sulfones. Phorate and its sulfoxide and sulfone persisted beyond 16 weeks in a siltloam at 25°C. The thiolate analogues degraded to low levels within 2 to 8 days. Phorate was highly toxic to a cricket, Achela pennsylvanicus (Bmweister), in direct soil bioassay tests. A lack of contact and fumigant toxicity against crickets suggested that phorate sulfoxide and phorate sulfone were tightly absorbed by soil constituents. The toxicity of soil treated with phorate sulfoxide was greater several weeks after application than it was immediately following treatment because small amounts of the sulfoxide were converted to phorate. The conversion of phorate sulfoxide to phorate in soil was verified with gas chromatography, column chromatography, and insect bioassay.
Document Type: Research Article
Publication date: February 1, 1970
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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.