醚菌酯50%干悬浮剂在草莓及土壤中的残留动态研究

［目的］明确醚菌酯在草莓和土壤中的残留动态情况。［方法］于2007～2008年，在天津、吉林、南京和昆明，设3 000倍液和2 000倍液2个剂量，对醚菌酯50％干悬浮剂在草莓及土壤中的消解动态和最终残留量进行了试验。［结果］在天津地区，醚菌酯在草莓和土壤中的半衰期分别为6.4 和12.6 d; 在吉林地区，醚菌酯在草莓和土壤中的半衰期分别为8.3和16.2 d;在南京地区，醚菌酯在草莓和土壤中的半衰期分别为5.2 和8.3 d; 在昆明地区，醚菌酯在草莓和土壤中的半衰期分别为6.3和12.3 d。施药后间隔3、5、7 和14 d的草莓中醚菌酯的残留量均低于1 mg/kg。［结论］醚菌酯50％干悬浮剂在草莓中合理使用的准则为：按3 000倍液在草莓上喷雾使用3次，安全间隔期为3 d，最高残留限量推荐值为1 mg/kg。

Residual Dynamics of Dry 50% Kresoxim-methyl Suspending Agent in Strawberry and Soil

Objective]The research aimed to make clear the residual dynamics of kresoxim-methyl in strawberry and soil.Method] Two dosages of solution diluted at 3 000 times and 2 000 times were applied in Tianjin,Jilin,Nanjing and Kunming in 2007～2008,the degradation dynamics and final residue of dry 50% kresoxim-methyl suspending agent in strawberry and soil were tested.Result] The half-life of kresoxim-methyl was 6.4 d in strawberry and 12.6 d in soil in Tianjin area; the half-life of kresoxim-methyl was 8.3 d in strawberry and 16.2 d in soil in Jilin; the half-life of kresoxim-methyl was 5.2 d in strawberry and 8.3 d in soil in Nanjing; the half-life of kresoxim-methyl in Kunming was 6.3 d in strawberry and 12.3 d in soil.The kresoxim-methyl residues in strawberry were all lower than 1 mg/kg for interval of 3,5,7 and 14 d after pesticide application.Conclusion] The rule of reasonable use of 50% kresoxim-methyl DF in strawberry was:spraying on strawberry for 3 times by the drug solution diluted at 3 000 times and the safety interval time was 3 d.The recommended value of the highest residue limit was 1 mg/kg.