1 Yangzhou Polytechnic University，Agricultural Production Safety and Environmental Protection Engineering Technology
Research Center of Jiangsu Province，Yangzhou 225009，Jiangsu，China；2 School of Horticulture and Plant Protection，
Yangzhou University，Joint International Research Laboratory of Agriculture & Agri-Product Safety（Yangzhou
University），Yangzhou 225009，Jiangsu，China；3 Yangzhou Nuofeng Agricultural Science and Technology Co. Ltd.，
Yangzhou 225127，Jiangsu，China
Pesticide preparation form has great effect on its control effect，duration efficacy and residual in
environment．In order to understand the optimum application amount and safety interval of rotenone，this study
analyzed the degradation dynamics and terminal residue of 2.5% rotenone microcapsule suspension on pakchoi and
in soil by high performance liquid chromatography（HPLC）．The results showed that the degradation dynamic
equations of rotenone on pakchoi and in soil fitted the first-order reaction dynamic equation．Their half-lives were
2.58-2.74 days and 2.88-3.07 days，respectively．When 2.5% rotenone microcapsule suspension was applied at 1.50
kg·hm-2 or at 2.25 kg·hm-2，the final residual concentration of rotenone on pakchoi and in soil was conformed to
the residual requirements and it is safe to use．
