Influence of selected pesticides on the microbial degradation of14C-triallate and14C-diallate in soil

Publisher Website
Google Scholar
Abstract
Degradation in soil of [allyl-2-14Ctriallate and [carbonyl-14 Cdiallate herbicides, as affected by other selected pesticides, was studied in an incubation system that allowed recovery of 95 to 100% of added14C. The amount and sequence of pesticide additions simulated field use in the protection of wheat (triallate) and sugar beets (diallate). Neither the rate nor the pattern of triallate degradation in soil was influenced by the following sequence of formulated pesticides: dinoseb acetate, (bentazon + dichlorprop + 2,4,5-T), 2,4-D, (chlorcholinchloride + cholinchloride), tridemorph, and thiophanate. Similarly, diallate degradation was unaffected by pyrazon, dimethoate, and thiophanate. The effect of azinphosmethyl was unclear. In contrast, chlorpyrifos reduced diallate degradation by approximately 14% relative to that occurring in the insecticide's absence. This effect was caused by chlorpyrifos and not its formulation components. Chlorpyrifos was also found to partially inhibit degradation of triallate in soil. Inhibition of neither herbicide was considered to be of ecological significance. Triallate, diallate, and thiophanate were applied at 1μg/g; all others were at 2μg/g.