氰氟草酯(XDE-537)在土壤中的降解

在杭州市富阳郊区水稻田，研究了除草剂千金（有效成分为氰氮草酯，代号XDE-537）在土壤中的降解动态，测定了土壤样品中的XDE-537及其降解产物。结果表明，氰氟草酯在土壤中迅速降解至检测限以下，分解首先生成氰氟草酯的丙酸同系物（ACID），进一步形成的降解产物为无除草活性的二酸同系物（DIACID）。ACID的降解较缓慢，DIACID的形成与ACID的降解成负相关。由于氰氟草酯、ACID和DIACID在土壤环境中均分解较快，可以认为千金在环境中属非滞留性除草剂。

Degradation of cyhalofop-butyl (XDE-537) in soil

A study was carried out to investigate the degradation dynamics of cyhalofop butyl (XDE 537) in soil, which is an active ingredient of a herbicide Clincher.Samples were collected from paddy fields in Fuyang, Hangzhou, Peoples Republic of China and XDE 537 and its degradation products were determined. Cyhalofop (ACID) was observed to be the first degradation product that later changed into inactive form DIACID. XDE 537 was found to undergo almost instant degradation in soil and to levels below the detection limit. ACID was comparatively slower although fairly fast in fact (five days). It was observed that most of the DIACID is derived from ACID. Because of the rap id reaction in soil and eventual disappearance of XDE 537, ACID and DIACID, it was suggested that the herbicide Clincher is nonpersistent in the environment.