Abstract: The degradation dynamics and terminal residue trials of oxyfluorfen(20% AC) on rice and its ecosystem were carried out in Zhejiang and Guizhou Province. The tesults showed that this herbicide was swiftly decomposed in rice plant and paddy water. The degradation half life in the two sites were 2.1 days, 1.6 days for rice plant, and 1.0 day, 2.5 days for paddy water, respectively. In contrast, paddy soil showed a remarkable difference in the degradation behavior, with a half life of 9.1 days in Zhejiang and 36.1 days in Guizhou. When sprayed at rate of 150-240 g(ai) / ha, 7 days after transplanting, no oxyfluorfen residues were detected in harvested rice grain, plant, soil and water. Thus, utilization of oxyfluorfen in paddy field would cause little residue concerns.

Key words: Oxyfluorfen, Residue, degradation, Herbicide, rice

关键词: 乙氧氟草醚, 残留, 降解, 水稻, 除草剂