Sorption, Movement, and Dissipation of Tebuthiuron in Soils

Publisher Website
Google Scholar
Abstract
Adsorption of tebuthiuron N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N’-dimethylurea appeared to be related to organic matter and clay content. After six successive desorption extractions, 40% of the tebuthiuron was adsorbed in soil with 4.8% organic matter but less than 1% was adsorbed in soil with 0.3% organic matter. Differences in adsorption were also reflected in the activity of tebuthiuron on soybeans [Glycine max (L.) Merr.] and corn (Zea mays L.) where it took 4.9 and 9.5 times as much tebuthiuron, respectively in soil with the greater adsorption to reduce growth by 50%. Soil mobility of tebuthiuron was identical to fluometuron[1,1-dimethyl-3-(α,α,α-trifluoro-m-tolyl),urea] in three soils tested. Soil mobility of herbicides was greater in soil with low organic matter and low clay content. Both temperature and soil moisture had an effect on persistence of tebuthiuron. Greater dissipation occurred at 15% soil moisture and 30 C than at lower moisture and temperature levels.