Persistence and Degradation of Pyrazosulfuron-Ethyl in Soils of Karnataka

Persistence of pyrazosulfuron-ethyl was studied in three different soils (Shimoga, Mandya and Chamrajanagar) of Karnataka under three moisture regimes (maximum water holding capacity, half maximum water holding capacity and submergence). The persistence of pyrazosulfuron-ethyl indicated a close correspondence to first order exponential degradation kinetics in soils and mainly influenced by soil organic matter and moisture. Faster disappearance was noticed under submergence followed by maximum water holding capacity and half maximum water holding capacity in all soils. Persistence of pyrazosulfuron-ethyl was lower in Shimoga soil followed by Chamarajanagar and Mandya under all moisture regimes. Half lives for pyrazosulfuron-ethyl under half maximum water holding capacity, maximum water holding capacity and submergence ranged from 74.6 to 85.5, 57.7 to 62 and 42.9 to 53.8 days, respectively.