刘国翠

摘要 [目的]探讨有机氯类农药对土壤动物的毒害作用。[方法]对棘跳虫进行不同濃度的滴滴涕（DDT）暴露胁迫，同时采用彗星实验技术研究棘跳虫细胞DNA的损伤程度。[结果]棘跳虫死亡率与DDT浓度呈明显正相关；DDT对棘跳虫24、48、72、96 h的半数致死浓度分别为31.83、24.28、17.15和13.93 μg/L，安全质量浓度为1.39 μg/L。不同浓度的DDT暴露均能引起棘跳虫细胞DNA的损伤，其最大损伤程度可达3级，且彗星尾长、尾距及彗星尾部DNA含量变化与DDT浓度有显著的剂量-效应关系。[结论]试验首次选取跳虫类作为指示动物，通过在细胞水平探究有机农药DDT对棘跳虫细胞DNA的损伤，为评估土壤污染物对土壤动物的毒害机制提供了新思路。

关键词 棘跳虫；滴滴涕；半数致死浓度；DNA损伤

中图分类号 S482.3+2；X171.5 文献标识码 A 文章编号 0517-6611（2017）13-0151-03

Toxic Effects of Dichlorodiphenyltrichloroethane on the Springtails Onychiuyus fimeitayius linnaeus

LIU Guo-cui

（College of Life Sciences， Liaocheng University， Liaocheng， Shandong 252000）

Abstract [Objective] The aim was to study toxic effects of dichlorodiphenyltrichloroethane on the springtails Onychiuyus fimeitayius linnaeus. [Method] The effects of pp-dichlorodiphenyltrichloroethane （DDT） on DNA damage in the springtails of Onychiuyus fimeitayius linnaeus were studied by comet assay. Meantime， the mortality of the springtails was observed after different concentrations of DDT exposure. [Result] The DDT had significant toxic effect on the mortality of the springtails. The median lethal dose was 31.83， 24.28， 17.15， 13.93 μg/L on 24， 48， 72 and 96 h， respectively. The safe concentration was 1.39 μg/L. The DNA damage of springtails cells could be induced under the different mass concentrations of DDT， and the maximum damage degree could reach to 3 levels. The effects of DDT stress on comet tail length， tail length and DNA content in the tail of springtails cells were significantly related to the dose-effect relationship. [Conclusion] It provides a new idea to evaluate the toxicity mechanism of soil pollutants to soil animals， by using the springtails as the indicator animal.

Key words Onychiuyus fimeitayius linnaeus；Dichlorodiphenyltrichloroethane；Median lethal dose；DNA damage

棘跳虫（Onychiuyus fimeitayius linnaeus）属于无翅亚纲弹尾目跳虫科的一类农业昆虫。由于较强的环境耐受力与繁殖力，棘跳虫对蔬菜、食用菌等经济作物的危害日益严重，已成为制约经济作物健康发展的害虫之一。

人工合成的有机氯农药滴滴涕（DDT）因具有极好的杀虫效果，被广泛应用于农业害虫及疟疾和斑疹伤寒等虫媒传染病的控制。据统计，我国累计使用DDT总量达46.4万t，占世界DDT使用总量的 25.8%[1]。土壤是DDT最主要的环境介质，人类活动产生的大量DDT经过各种途径进入土壤，通过食物链最终在动物体脂肪组织内高度富集，其蓄积系数可达百万倍。调查显示，DDT使用量最高的是华东和华北地区，其次是华南地区和新疆棉田地区[2-3]。

有关杀虫剂对跳虫类的防治工作已取得一定成效。……