咪鲜胺及其代谢物在水稻中的残留检测方法及残留动态

Residue Detection and Degradation of Prochloraz and its Metabolites in Rice

采用气相色谱电子捕获检测(GC-ECD)研究了杀菌剂咪鲜胺及其代谢物在水稻中的总残留量检测方法.经简单净化后将咪鲜胺及其代谢物在高温下与吡啶盐酸盐反应,转化为2,4,6-三氯苯酚进行测定.咪鲜胺在各样品中的添加回收率为72.9% ～103.4%,变异系数在1.46% ～9.38%之间.残留动态研究表明,咪鲜胺在水稻苗中消解较快,半衰期仅为3.4 d;到水稻收获时,在用166.6 mg/L浸种处理后的稻米和稻秆中分别检出了0.025和0.056 mg/kg的残留量,其他样本中均未检出咪鲜胺的残留.

Residue detection and degradation of prochloraz 45% EC and its metabolites in rice were investigated and their residues were determined with GC-ECD. After simple cleaning-up of the (samples), prochloraz and its metabolites reacted with the pyridine chloride at high temperature, the product 2,4,6-trichlorophenol was then detected. The fortified recoveries of prochloraz were 72.9%～103.4%, the CVs were 1.46%～9.38%. The results obtained from two years experiments showed that the degradation of prochloraz in rice seedling was fast, and its half-life was only (3.4 days.) After a growing season, only in the sample from high dosage of application, the residue in rice grain and rice straw were 0.025 and (0.056 mg/kg) respectively, no detectable residue was found in the other samples.