【作者】 汪海燕； YANG Zhen； LIU Ru-yang； FU Qiu-guo； ZHANG Su-fen； LI Ju-ying； ZHAO Xiao-jun； YE Qing-fu； WANG Wei； LI Zhong；

【Author】 WANG Hai-yan;YANG Zhen;LIU Ru-yang;FU Qiu-guo;ZHANG Su-fen;LI Ju-ying;ZHAO Xiao-jun;YE Qing-fu;WANG Wei;LI Zhong;Institute of Nuclear Agricultural Sciences,Key Laboratory of Nuclear Agricultural Sciences of Ministry of Agriculture and Zhejiang Province,Zhejiang University;

【机构】 浙江大学原子核农业科学研究所； Institute of Nuclear Agricultural Sciences,Key Laboratory of Nuclear Agricultural Sciences of Ministry of Agriculture and Zhejiang Province,Zhejiang University；

【摘要】 哌虫啶,1-（6-氯-3-甲基吡啶基）-5-丙氧基-7-甲基-8-硝基-1,2,3,5,6,7-六氢咪唑[1,2-a]吡啶,是华东理工大学和江苏克胜集团共同开发的一个高效新烟碱类杀虫剂品种。哌虫啶含有两个手性中心,四个对映异构体。为了减少其环境释放及其对人类健康的危害,本研究采用手性HPLC和超临界流体色谱法,分离得到四种¹⁴C标记的对应异构体RR,SS,SR和RS,并以此作为示踪剂,综合运用核素示踪和现代仪器分析技术,着重研究¹⁴C-哌虫啶手性对映体在油冬菜中的吸收、运转及分布规律及其可能的立体差异性。研究结果表明:1)叶片处理96 h后,哌虫啶的四种对映体在油冬菜汇总的吸收量分别为引入总量的35.40%,36.66%,36.80%,和38.20%,手性对映体之间不存在显著的选择性吸收差异（p<0.05）,而对映异构体之间未发现显著差异（p>0.05）,4种异构体在植物体内的运转分布量依次顺序为标记叶>标记叶以下部分>标记叶以上部分>茎>根。3)根系吸收试验数据表明,处理72小时后哌虫啶4种立体异构体在油冬菜中的根系吸收和运转均存在明显的选择性差异。这些发现有利于哌虫啶异构体在蔬菜中的正确合理使用,并为哌虫啶单个对映异构体的环境安全评价提供了有用的信息。更多还原

【Abstract】 Paichongding,a neonicotinoid chiral insecticide containing two chiral centers,is a promising substitute for the widely used imidacloprid because it is effective against many imidacloprid-resistant insects.In this study,four optically-pure stereoisomers of Paichongding with 5R,7R,5S,7S,5S,7R,and 5R,7S were employed in both foliar and root of Chinese pak choi to investigate the stereoselective uptake and distribution of the insecticide in pak choi.The results showed,after foliar application,total absorption of individual ¹⁴C-Paichongding stereoisomers into pak-choi plants demonstrated no stereoselectivity between the enantiomers.The translocation of the four absorbed stereoisomers within pak choi occurred in both acropetal and basipetal directions and the transport of ¹⁴C from enantiomers 5R,7R and 5S,7S were significantly higher than enantiomers 5R,7S and 5S,7R.The statistically significant stereoselective translocation inside plants was observed between Paichongding epimers.Root treatment revealed that enantioselective and diastereoselective root uptake into pak-choi plants were both found between the four enantiomers.The enantiomers of 5R,7S and 5S,7R were more readily taken up by roots,and more readily accumulated in edible leaves than 5R,7R and 5S,7S.These results will help to develop an understanding of the proper application of Paichongding isomers in vegetables,and give useful information for food and environmental assessments of chiral pesticides.更多还原