代森锰锌在黄瓜和土壤中的残留动态

Residue Dynamics of Mancozeb in Cucumber and Soil

采用田间试验方法,研究了代森锰锌在黄瓜及土壤中的消解动态和最终残留,气相色谱法定量分析。此方法黄瓜中代森锰锌的平均回收率为89.02%～95.50%;土壤中代森锰锌的平均回收率为86.59%～93.03%。结果表明,代森锰锌在黄瓜和土壤中消解较快,其半衰期分别为1.57～3.51天和3.85～11.44天。在黄瓜上使用精甲霜灵·代森锰锌水分散粒剂,按照推荐使用剂量最多施药3次,最后一次施药2天后,采收的黄瓜中代森锰锌的残留量均小于2mg/kg。

A field experiment was conducted to reveal residue dynamics of mancozeb in cucumber and soil.The residues of mancozeb in cucumber and soil were determined by gas chromatography with ECD detector.The average recoveries of mancozeb were in a range of 89.02%-95.50% in cucumber and 86.59%-93.03% in soil.The results showed that the mancozeb dissipated rapidly in cucumber and soil.The half-life of mancozeb in cucumber and in soil were 1.57-3.51 days and 3.85-11.44 days respectively.When the cucumber was sprayed three times with mancozeb W.D.G,and the last application was done 2 days before harvesting,the final residues of mancozeb in cucumber was lower than 2 mg/kg,demonstrating that it is safe to apply mancozeb to cucumber with the recommended rate.