Determination of residue of diflufenican in wheat and soil by ultra-high-pressure liquid chromatography and mass spectrometry conditions.

In order to clarify whether the application of diflufenican in the wheat field will produce residues in wheat plants and soil. In this experiment, ultra-high-pressure liquid chromatography was used to determine the residues of diflufenican in wheat plants, grains, and soil, which provided a new theoretical basis and technical guidance for the safe production of wheat. The results showed that the average diflufenican recovery per added level in wheat and soil were in the range of 85.7% to 91.3%, relative standard deviations were all in a range of 2.43% to 6.00%, and the minimum detectable amount of diflufenican was 1.0 × 10-10  g kg-1 . With the increase of wheat growing days and soil layers, the residues of diflufenican in wheat plants and soil became lower. The order of residual amount of diflufenican in the growth period were heading period, flowering period, filling period and maturing period. The order of residual amount of diflufenican in different soil layers was 0-20, 20-40, 40-60, 60-80 and 80-100 cm respectively from the top to the bottom. In addition, with the increase of the dosage of diflufenican, the residual amount of diflufenican becomes higher. Thus, the residual amount of diflufenican after 2.0 times applied amount was higher than the 1.0 time applied amount. The residual amounts of diflufenican in wheat and soil were very small, far below the value of the maximum residue limit (MRL) on wheat provided by China. Under the applied amount administered in this experiment, a single spray of diflufenican in wheat trifoliate is safe for wheat, humans and livestock. © 2020 Society of Chemical Industry.