氟虫腈在甘蓝及土壤中的残留动态研究

Dissipation of Fipronil in Cabbage and Soils at Different Sites

通过对甘蓝及土壤中氟虫腈残留量的气相色谱(GC-ECD)分析,比较了济南、昆明两种植区的甘蓝及土壤中氟虫腈的残留动态。结果表明,在济南、昆明两地种植的甘蓝中,氟虫腈的半衰期基本一致(约0.7d),而在两地的土壤中,则存在显著性差异(半衰期分别为1.60d和4.96d)。高低剂量施药分析结果表明,低剂量2次施药、3d后采收与3次施药、7d后采收,氟虫腈的残留量均低于1×10-4mg.kg-1。

Fipronil insecticide has biological activity against vegetable pests and been widely used in China recently.The present research probed dynamics of fipronil degradation in cabbage and soils at fields of Jinan and Kunming,respectively.The tests were carried out in this study to evaluate impact of using fipronil in ecosystem and to provide basic information for this insecticide.A quantitative study of fipronil residue by GC-ECD showed that dissipation of fipronil in the soil of Jinan(half-life approx.1.60 d) was faster than that of Kunming(half-life approx.4.9 d).But there was just only a slight difference in cabbage from these districts(half-life approx.0.7 d).In addition,the final residues of fipronil in cabbage were both lower than 0.0001 mg·kg-1 after 3 d treatment with a low dosage of the fipronil(26.25 g a.i.hm-2) to spray twice at interval of 3 d or after 7 d treatment to spray with three times application.