Dissipation and residues of imidacloprid in radish and soil

Dissipation and residues of imidacloprid in radish and soil were determined by high perform liquid chroma-tography(HPLC).The results showed that,under the local environment and climate in the experiment field during the years 2001-2002,the half-lives of degradation of imidacloprid were 5.65 days,3.70 days,and 10.88 days,respectively,in the leaves,stems of the radishes and the soil.The maximum value of final residue of imidacloprid in radish was 0.075 mg/kg,which is much lower than the criterion of the residue limitation of imidacloprid on the Cruciferae vegetables issued by FAO.