Dissipation and Residues of N-(2-Bromophenyl)-2-(4,6-Dimethoxypyrimidin-2-Yloxy)Benzylamine Residues in Rape and Soil Under Field Conditions

摘要

N-(2-Bromophenyl)-2-(4,6-dimethoxypyrimidin-2-yloxy)benzylamine, compound A, is a highly active herbicide. Field trials indicate that it controls major weeds with a good tolerance on rape by postemergence application. In the present study, it was studied the dissipation behavior of compound A residues in rapes and soils. Analyses were carried out using high performance-liquid chromatography with diode array detection. The limits of detections (LOD) of compound A in rape plant and rape seed samples were 0.03 mg kg−1 and its in soil was 0.02 mg kg−1. At three different spiking levels mean recoveries and relative standard deviation (RSD) from spiked samples in five replicated experiment for each matrix were in the range 87.3%–96.4% and 2.9%–8.7%, respectively. The dissipation rate was found to vary with the nature of the studied sample. In soil, half-live were 33 and 25 days in Yunnan and Zhejiang, respectively, while in rape, it was 7.2 and 8.5 days. The residual amounts of compound A in rape and soil samples were below LOD after the recommended dosage and two times dosage. According to the calculation of the ADI of compound A and other data, the result suggest that the MRL for compound A in rape is 1 mg kg−1. Keywords N-(2-Bromophenyl)-2-(4,6-dimethoxypyrimidin-2-yloxy)benzylamine - Pesticide - Rape - Soil - HPLC–DAD