Fate of tribenuron-methyl in soil and water

Abstract

Persistence of tribenuron in different soil types (namely alluvial, black and red soil) having different pH values maintained at field capacity moisture regime and in water at three different pH levels i.e. 4, 7 and 9.2, respectively was studied under laboratory conditions at two levels of application, 1.0 and 2.0 mg^–1. Samples were processed periodically and analyzed by HPLC. Tribenuron dissipated to 91.04-90. 41% in

alluvial and black soil, whereas in red soil with pH 6.64, it dissipated to 94.7% by day 5 after fortification. The half-life values calculated from the first order dissipation kinetics varied from 1.67 in red soil with pH 6.1 to 3.47 in alluvial soil with pH 8.1, indicating that tribenuron is more persistent in soil with basic pH and degrades faster in acidic soil. Slowest dissipation was recorded at neutral and basic pH.