丁草胺在毛豆及其土壤环境中的残留动态研究

A Study on Residual Dynamics of Butachlor in Vegetable Soybean and Their Environmental Soils

2004、2005年对丁草胺在毛豆及其土壤环境中的残留动态进行研究。结果表明,土壤中丁草胺残留动态为:2004年施用量80g/666.7m2的按Ct=2.0046·e-0.1419t降解,DT50=4.9d、DT99=32.5d;施用量160g/666.7m2的按Ct=4.1023·e-0.1429t降解,DT50=4.9d、DT99=32.2d。2005年施用量80g/666.7m2的按Ct=2.0724·e-0.1315t降解,DT50=5.3d、DT99=35.0d;施用量160g/666.7m2的按Ct=4.4136·e-0.1352t降解,DT50=5.1d、DT99=34.0d。毛豆种植12～15d后植株中丁草胺残留量最高,其后逐渐降低,在毛豆采收时(种植后65d),除在土壤中尚能检测到痕量的丁草胺外,毛豆植株和豆荚中均未检测到丁草胺的残留量。对分析方法的适合性测定结果表明,方法的回收率土壤、毛豆植株和豆荚样品分别为82.6%～101.5%、87.6%～103.5%和85.0%～98.9%,RSD分别为1.95%～5.93%、1.67%～7.84%和3.78%～6.12%,最小检测量0.001ng,土壤和毛豆的最小检测浓度分别为0.001和0.0005mg/kg。

Residual dynamics of butchalor were studied in vegetable soybean and their environmental soils from 2004 to 2005, showing the residual dynamics of butchalor in soil as the following： in 2004, the dosage of 80g/666.7m^2 was degraded by Ct=2.0146.e^-0.1419t, DT50 4.9d, DT99 32.5d; the dosage of 160g/666.7m^2 was degraded by Ct=4.1023.e^-0.1429t, DT50 4.9d, DT99 32.2d; and in 2005, the dosage of 80g/666.7m^2 was degraded by Ct=2.0724. e^-0.1315t, DT50 5.3d, DT99 35.0d; the dosage of 160g/666.7m^2 was degraded by Ct=4.4136.e^-0.1352t, DT50 5.1d, DT99 34.0d. The residual content of butachlor in the plants was the highest in 12d-15d after seedling, then it lowered gradually. When vegetabe soybean was harvested after seedling in 65d, only trace butachlor could be determined in the soils, no residual could be determined in the plants. On the suitability of the analysis method, the results of determination showed that the average recovery of soil samples were 82.6%-101.5%, RSD 1.95%-5.93%; the plant samples were 87.6%-103.5%, RSD 1.67%-7.84%; vegetable soybean samples were 85.0%-98.9%, RSD 3.78%-6.12%. MDQ was 0.001ng, MDC of soil samples and green soybean samples were 0.001mg/kg and 0.0005mg/kg respectively.