异丙甲草胺在烟叶和土壤中的残留动态研究

为了解异丙甲草胺在烟叶和土壤中的降解规律,通过湖南和山东两地的大田试验,采用高效液相色谱法研究了异丙甲草胺在烟叶和土壤中的消解动态和最终残留量.结果表明:异丙甲草胺在烟叶中降解较慢,在湖南和山东烟叶中的半衰期分别为9.47 d、8.49 d,土壤中的半衰期分别为10.30 d、11.12 d.施药量为100 g/667m2时,烟叶成熟后异丙甲草胺在湖南烟叶和土壤中的残留量为0.004～0.052 mg/kg;在山东烟叶和土壤中的残留量为0.007～0.067 mg/kg.施药量为150 g/667m2时,烟叶成熟后异丙甲草胺在湖南烟叶和土壤中的残留量为0.009～0.061 mg/kg;在山东烟叶和土壤中的残留量为0.011～0.071 mg/kg,均低于规定的MRL值,说明异丙甲草胺是易降解农药,在烟草上使用是安全的.

Residual Dynamics of Metolachlor in Tobacco Leaves and Soil

In order to understand the degradation rules of metolachlor in tobacco leaves and soil,the field experiments in Hunan and Shandong were conducted to study the degradation dynamics and the final residue amount of metolachlor in tobacco leaves and soil by high-performance liquid chromatography.The results showed that metolachlor degraded slowly in tobacco leaves,its half-life in tobacco leaves from Hunan and Shandong were 9.47 d and 8.49 d,respectively;its half-life in soil from Hunan and Shandong were 10.30 d and 11.12 d.respectively.When applying amount of metolachlor Wag 1500 g/hm2,the metolachlor residue in matured tobacco leaves and soil from Hunan were both in the range of 0.004 to 0.052 mg/kg and that from Shandong were both in the range of 0.007 to 0.067 mg/kg;when applying amount of metolachlor Wag 2 250g/hm2,the metolachlor residue in tobacco leaves and soil from Hunan were both in the range of 0.009 to 0.061 mg/kg and that from Shandong were both in the range of 0.011 to 0.071 mg/kg;all of these metolachlor residue amounts were lower than the statutory MRL values.The results indicated that metolachlor is an easily degradable pesticide;it is safe for tobacco to use.