Residues Determination of Pyraclostrobin Dimethomorph in Cabbage and Soil

Pyraclostrobin dimethomorph is a mixture of pyraclostrobin and dimethomorph fungicide.A method was established for determining pyraclostrobin and dimethomorph residues in cabbage and soil.Residues were extracted with a mixture of acetone and water.Liquid-liquid extraction was used with dichloromethane.The extracts were cleaned up by a column of aluminium oxide(neutral).Residues of pyraclostrobin and dimethomorph were determined by gas chromatography equipped with micro-electron capture detector(μ-ECD).[Results] The LOD(limit of detection) of pyraclostrobin and dimethomorph were 2.0×10-11 and 1.0×10-11 g,respectively,and the LOQ(limit of quantification) was 0.005 mg/kg.The different addition level of pyraclostrobin and dimethomorph were 0.01,0.05,0.50 mg/kg and 0.1,1.0,5.0 mg/kg,and the average recovery of soil and cabbage plant were 84.8 to 108.6% and 0.1,1.0,5.0 mg/kg,respectively.And coefficients of variation were 1.74-3.67%,3.32-3.87% and 1.54-2.78%,3.48-3.84%,respectively.[Conclusions] The method was precise and simple.It was applicable to the determination of pyraclostrobin?dimethomorph residues in cabbage and soil.