SPE-HPLC法检测噻吩磺隆在北京棕壤土中的消解

Determination of thifensulfuron-methyl degradation in Beijing brown soil with SPE-HPLC

为明确噻吩磺隆在北京地区棕壤土麦田环境下的消解动态,建立了使用固相萃取小柱前处理结合高效液相色谱分析方法 (SPE-HPLC),并对田间小区试验样品进行分析,结果表明:利用磺酰脲类专用固相萃取小柱前期净化分离,高效液相色谱分析回收率76.14%~86.48%,相对标准偏差5.22%~7.93%。田间实验结果显示,75%噻吩磺隆水分散粒剂推荐用药量为45.0g/hm2,其在土壤中的消解符合动态方程C=0.212e-0.34t(r2=0.993),半衰期是2.03d,消解95%需8.98d;加倍用药量为90.0g/hm2时,其在土壤中的消解动态方程C=0.397 3e-0.36t(r2=0.952),半衰期是1.92d,消解95%需8.75d。结果表明,该除草剂在北京棕壤土麦田中降解较快,施药14d后均未检出噻吩磺隆在土壤中的残留,对当季小麦株高没有影响。

In order to clarify the degradation of thifensulfuron-methyl in Beijing brown soil,the method of SPE-HPLC(solid phase extraction and high performance liquid chromatography)was employed to analyze the samples from wheat field.The results showed that the recovery rate was 76.14%~86.48%,and the relative standard deviations was 5.22%~7.93%.Moreover,when the doze of 75%WDG(water dispersed granule)thifensulfuron-methyl was 45.0g/hm2,the degradation dynamic equation was C= 0.212e-0.34t(r2=0.993),with T50 was 2.03 d,and T95 was 8.98d;when the doze of 75% WDG thifensulfuron-methyl was 90.0g/hm2,the degradation dynamic equation was C=0.3973e-0.36t(r2=0.952),with T50 was 1.92 d,and T95 was 8.75 drespectively.The results illustrated that thifensulfuron-methyl degraded fast and could not be determined in brown soil after being used 14 days,thus it had no effect on wheat growth.