Degradation of oxadiazon in Kalyani alluvial soil

Residual fate and behaviour of the herbicide oxadiazon in Kalyani soil, pad dy straw and grain were studied under subtropical conditions, in West Benga l following application @ 1 kg and 2 kg ha(-1). Dissipation of oxadiazon in soil followed first-order kinetics and DT50 values ranged from 44 to 45 da ys. Residues at harvest in paddy grains and straw were also studied. Degrad ation of oxadiazon after 60 days of incubation at 28(+/-1)degrees C in allu vial soil at water holding capacity yielded 10 metabolites of which four we re characterised by spectroscopy. (C) 1999 Society of Chemical Industry.