煙草及土壤中精甲霜靈殘留分析方法和降解規(guī)律研究

Residue Analysis Methods and Degradation Regularity of Metalaxyl-M in Tobacco Leaves and Soils

摘要: 對煙草和土壤中精甲霜靈（Metalaxyl-M）采用丙酮/甲醇（1：1,，v/v）提取,，弗羅里硅土加活性炭混合層析柱凈化，液相色譜紫外檢測器（UV）測定,。試驗結(jié)果表明,，鮮煙葉、土壤中精甲霜靈回收率分別為92.14%～97.12%,、93.36%～96.46%,；相對標準偏差分別為3.2%～4.8%、2.2%～2.9%,。精甲霜靈在煙葉中的消解較快,，半衰期為1.2～1.5 d,；而在土壤中相對較慢，半衰期為6.39～12.77 d,。

Abstract: Metalaxyl-M residues in tobacco leaves and soil were analyzed by high performance liquid chromatography. In this method residues were extracted with acetone and methyl alcohol, cleaned up on a column of florisil and activated carbon mixtures, and determined with an ultraviolet (UV) detector. Recoveries were 92.14%~97.12% for fresh leaves and 93.36%~96.46% for soisl respectively, and relative standard deviations (RSDs) were 3.2%~4.8% and 2.2%~2.9% respectively. The degradation rates of metalaxyl-M were faster in tobacco leaves than in soils, and the degradation half-life times were 1.2~1.5 days in tobacco leaves and 6.39~12.77 days in soils.