[Objective] To clarify the residue and digestion dynamics of dichlorvos in carrot. [Method] A standardized field experiment was conducted and a method for the residue analysis of dichlorvos in carrot was established. [Result] 77.5％ dichlorvos EC was not detected in carrot and soil 3 days after application with 1 800 g a.i./hm2. The pesticide degradated quickly and did not cause accumulative residue. When the dichlorvos was divided into 2 and 3 times with 1 200 and 1 800 g a.i./hm2 respectively, the interval of the dosage was 7 d, and the carrots were collected from 5, 7 and 14 d after the last dosage, and the detectable residual amount was between 0.010 and 0.112 mg/kg. This concentration was lower than the MRL (0.2 mg/kg) of dichlorvos in dark vegetables.[Conclusion] It is suggested that the dosage of dichlorvos will not exceed 1 200 g a.i./hm2, the maximum application time will not exceed 3 times, and the safe interval is 7 days, when using recommended 77.5％ dichlorvos EC to control carrot disease.%[目的]明确敌敌畏在胡萝卜上的残留及消解动态.[方法]采用田间试验, 建立敌敌畏在胡萝卜中的残留分析方法.[结果]将77.5％敌敌畏乳油按1 800 g a.i./hm2施药3次后, 3 d后在胡萝卜和土壤中均未检出, 消解快, 不会造成累积性残留;当敌敌畏按1 200和1 800 g a.i./hm2, 分别施药2次和3次, 施药间隔为7 d, 于末次施药后5、7和14 d采收胡萝卜, 其残留量为0.010～0.112 mg/kg, 低于我国规定的敌敌畏在深色蔬菜中的最大残留限量值0.2 mg/kg.[结论]建议在使用77.5％敌敌畏乳油防治胡萝卜病害时, 用药量不超过有效成分1 200 g a.i./hm2, 最多施药3次, 采收安全间隔期为7 d.
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