Persistence of Imazosulfuron Residues in Rice Crop and Soil

The field dissipation study of imazosulfuron was conducted in kharif 2005. Imazosulfuron was applied at 30, 40, 50 and 60 g ai ha⁻¹, 4 days after transplanting of rice as post-emergence herbicide. Soil and plant samples were collected at 60,90 and 120 days after herbicide application and analyzed for residues. Rice grains and straw samples were drawn at harvest. The residue level of imazosulfuron in soil was found to be 0.002, 0.006, 0.0075 and 0.010 μg g⁻¹ after 60 days at 30,40, 50 and 60 g ha⁻¹ appllcation rates, respectively. However, no residues were found after 90 and 120 DAS. At harvest imazosulfuron residues were not detected in rice grains and straw.