Degradation and Leaching of Herbicide Imazosulfuron in Upland Soils
Degradation of imazosulfuron in upland soils was investigated under laboratory conditions using two kinds of 14C labeled imazosulfuron. Imazosulfuron degraded with half-life of approximately 40 days, and the major degradation pathway was the hydrolysis of the sulfonylurea bond to give ADPM and IPSN. The leaching studies of imazosulfuron using non-aged and aged soils were also conducted. It was found that imazosulfuron was less mobile in soils when the soil column was eluted with 0.02 N CaCl£² solution after 30 days of aging period of time compared to non-aging. Main degradation products, ADPM and IPSN, were adsorbed in soils stronger than imazosulfuron. It was suggested that imazosulfuron dissipates relatively fast in upland soils, and the leaching potential decreases with time. |