哒螨灵在棉花和土壤中的残留及消解动态研究

摘要

Dissipation dynamics and residues of pyridaben in cotton and soil were reported, and pyridaben was determined by GC-ECD. The fortified recoveries in cottonseed, cotton leaf and soil at 0.01-0.2 mg/kg were 82.36%-113.94% with the relative standard deviations of 1.76%-8.07%. The limit of detection of the analytical method was 1×10-11 g at a signal-to-noise ratio of 3, and the limits of quantification were 0.01 mg/kg in cottonseed, cotton leaf and soil. The dissipation dynamics of pyridaben in Henan and Hunan Province were investigated in 2011 and 2012. The results showed that the half-lives of pyridaben were 0.84-2.5 d in cotton leaf, 5.7-7.3 d in soil. The final residues of pyridaben in cottonseed were all less than 0.01 mg/kg. Pyridaben is an easily dissipated and low residues pesticide, so it could be safely used in cotton with the maximum active ingredient dosage of 112.5 g/hm2, the spray times of 3, preharvest interval (PHI) of 14 d.%研究了哒螨灵在棉花和土壤中的残留及消解动态，采用气相色谱-电子捕获检测器进行定量分析。哒螨灵在棉籽、棉花叶及土壤中添加平均回收率为82.36%～113.94%，相对标准偏差为1.76%～8.07%。其最小检出量为1×10-11 g，在棉籽、棉花叶及土壤中的最低检测浓度均为0.01 mg/kg。2011和2012年在河南省和湖南省的田间残留试验结果表明：哒螨灵在棉花叶中的消解半衰期为0.84～2.5 d，土壤中的消解半衰期为5.7～7.3 d；哒螨灵在棉籽中的最终残留量均≤0.01 mg/kg，说明该药为低残留、易消解农药。建议采用10%哒螨灵微乳剂防治红蜘蛛，最高有效成分用量为112.5 g/hm2，最多施药3次，安全间隔期为14 d。