摘要
为了在设施蔬菜上科学安全地使用氯氰菊酯农药,采用气相色谱和田间试验方法,对10%氯氰菊酯乳油在露地、大棚小白菜上的残留动态和最终残留进行了对比研究。小白菜样品采用乙腈超声提取、固相萃取净化和气相色谱-电子捕获检测器（GC-ECD）测定,在0.1～1.0 mg/kg的添加水平下,氯氰菊酯的平均回收率为92.9%～106.0%,相对标准偏差（RSD）为2.8%～8.4%,最低检测浓度为0.01 mg/kg。田间试验表明,氯氰菊酯在小白菜上降解较快,降解速度与其栽培方式有关,施药剂量为推荐剂量的2倍（有效成分为90 g/hm2）时,在露地小白菜上的半衰期为1.856天,7天可降解90%以上;在大棚小白菜上的半衰期为2.314天,10天可降解90%以上。在有效成分90 g/hm2剂量下施药3次,2次施药间隔7天,氯氰菊酯在露地栽培小白菜上的安全间隔期为3天,大棚栽培条件下的安全间隔期应延长至7天。
In order to apply cypermethrin scientifically and safely to greenhouse vegetables, the residuedynamics and final residues of 10% cypermethrin EC on pakchoi in open field and greenhouse were comparedby using the methods of gas chromatography and field experiment. The pakchoi samples were extracted byacetonitrile with ultrasound assistance, cleaned up by self-made florisil solid-phase extraction column anddetermined by gas chromatograph with electronic capture detector（GC- ECD）. The mean recoveries ofcypermethrin in samples ranged from 92.9% to 106.0% at the added levels of 0.1- 1.0 mg/kg with relativestandard deviation（RSD） of 2.8%-8.4%, and the minimum detectable concentration was 0.01 mg/kg. The fieldexperiments indicated that cypermethrin was rapidly degraded in pakchoi. The degradation velocity was relatedto cultivation methods. With double recommended dosage（effective constituent concentration was 90 g/hm2）,the half-lives of cypermethrin in open field and greenhouse were 1.856 d and 2.314 d, and degraded above90% after 7 d and 10 d, respectively. When pakchoi was treated for 3 times at an interval of 7 d with effectiveconstituent concentration of 90 g/hm2, the safety interval of cypermethrin in pakchoi under open field was 3days, which should be extended to 7 days under greenhouse conditions.
出处
《中国农学通报》
2015年第11期200-204,共5页
Chinese Agricultural Science Bulletin
基金
江苏省农业科技自主创新基金"洞庭碧螺春茶园肥药减量高效安全生产技术研究"([SCX(14)2163])
苏州市科技支撑项目"设施叶类蔬菜安全生产及监测技术研究"(SNG201438)
苏州市科技基础设施建设项目"苏州市农产品农药残留检测技术研究及服务平台"(SZP201205)
关键词
小白菜
氯氰菊酯
农药残留
动态
pakchoi
cypermethrin
pesticide residue
dynamics
