禾草灵在大田系统中迁移、降解动态规律研究

STUDIES ON THE MOVEMENT AND DEGRADATION OF DICLOFOP-METHYL IN AGROSYSTEM

采用大田残留动态试验实测数据,借助药物动力学分室模型,研究了禾草灵在我国部分地区小麦、甜菜大田系统的的迁移、降解规律。该方法不仅得到了禾草灵的降解参数,而且得到了作物对土壤中残留禾草灵的吸收速率常数。本文还用GC/MS技术,分析鉴定了禾草灵的九种降解产物,推测了禾草灵的部分降解途径。

The movement and degradation of the herbicidal ester Diclofop-methyl, in plant and soil, were studied under the field conditons. Firstly,the samples of wheat, sugar beet and soil, tested from 1984 to 1986, were extracted by acetone-petroleum ether, cleaned up on a certain column (containing A12O3 and Ag-Al2O3) and then analyzed with GC-ECD techniques. The mean recoveries of residual Diclofop-methyl were 75.1% to 95.6%.Secondly, the approach to the compartmental model was estabilished by the concept of pharmacokinetics. Solving equation and establishing parameters were discussed. In the plantsystem, the half-life of 36% emulsion Diclo-fop-methyl were from 2.9d to 3.2d, and in the soilsystem, from 4.3d to 6.0d.In the third aspect, nine metabolites of degradation of Diclofop-methyl were found by GC/MS and the primary pathways in photodegradation of pure Diclof op-methyl were proposed.