Clay soil, Column, Imazethapyr, Leaching, Movement, Rainfall

Though herbicides are designed as biologically active but often their residues are found in crop produce and water. Herbicides may reach to ground water through runoff, drift, untargeted spray and heavy rain. Therefore, leaching beahiviour of imazethapyr, was evaluated in soil columns under natural rainfall conditions. Imazethapyr was applied at 100 and 200  g/ha on the soil columns. Columns were arranged randomly and allowed to receive approximately 850 mm rain for three months. Soil and leachates were analyzed for imazethapyr residues. Maximum concentration of imazethapyr was recovered from 0-10 cm depth. Results indicated that imazethapyr could leach in clay loam soil up to the depth of 70 cm.