氯虫苯甲酰胺对2种跳虫的繁殖毒性与氧化胁迫

为研究氯虫苯甲酰胺 (chlorantraniliprole, CAP) 对跳虫的繁殖毒性和氧化胁迫效应，以2种跳虫白符跳Folsomia candida Willem和奇裸长跳Sinella insolens为受试生物，分别测定了CAP对其28 d和21 d的繁殖毒性和暴露于CAP亚致死剂量（白符跳0.0533 mg/kg，奇裸长跳100 mg/kg）10 d内，2种跳虫体内抗氧化防御系统受到的影响。结果表明，CAP对白符跳和奇裸长跳的繁殖率半抑制浓度 (EC_50-repro) 分别为0.533 mg/kg dw (95%置信区间为0.370~0.769 mg/kg dw) 和 > 1 000 mg/kg dw，毒性差异明显。暴露于亚致死剂量的CAP 0、2、4、6和10 d后，CAP能不同程度地影响2种跳虫的抗氧化防御系统。暴露初期过氧化氢酶 (CAT) 活性分别上升113%和108%，谷胱甘肽还原酶 (GR) 活性分别上升141%和74.6% (P < 0.05)，随暴露时间延长，2种酶活性逐渐下降，最终趋向对照组水平；总谷胱甘肽 (TG) 活性水平始终维持在对照组以上，并在第6天达到最高；谷胱甘肽-S-转移酶 (GST) 活性在暴露初期分别下降38.4%和21.6% (P < 0.05)，随暴露时间延长逐渐升高，回到对照组水平；脂质过氧化物 (LPO) 含量随暴露时间延长而呈现先上升后下降的趋势，变化幅度较小；而金属硫蛋白 (MT) 含量则未随暴露时间的延长而出现显著变化。本研究结果表明，白符跳对CAP更为敏感，可作为土壤环境中CAP的指示生物。CAT、GR和GST是指示CAP短期胁迫的较适宜的生物标志物，而TG和LPO可以作为指示CAP中长期胁迫的生物标志物。

Reproductive toxicity and oxidative stress of chlorantraniliprole to two springtails (Collembola)

Chlorantraniliprole (CAP) is a pesticide widely used in crop protection. In this study, the toxic effects of CAP on the soil system were evaluated. The non-target soil springtails, namely Folsomia candida Willem and Sinella insolens were exposed to CAP for 28 and 21 days, respectively, to examine the reproductive toxicity of CAP and they were exposed to CAP for 10 days in oxidation stress tests. The EC_50-repro of CAP to those two species were 0.533 mg/kg dw (95% confidential interval of 0.370-0.769 mg/kg dw) and >1000 mg/kg dw, respectively. The activities of catalase (CAT), glutathione reductase (GR), glutathione-s-transferase (GST), the content of total glutathione (TG), lipid peroxidation (LPO) and metallothionein (MT) were measured after the springtails were exposed to sub-lethal CAP doses after 0, 2, 4, 6 and 10 days. Under experimental concentrations of CAP, the activities of CAT increased significantly at the early stage of exposure by 113% and 108% (P <0.05), resectively. Aubsequently, the activities of GR were increased by 141% and 74.6% (P <0.05). Eventunally, both the activities decreased to the same levels of the control group. The activities of GST decreased significantly at day 4 by 38.4% and 21.6% (P <0.05), respectively. Then they increased to the same level of control group at day 10. CAP exposure also resulted in an increase in the TG levels within 6 days. Then TG level decreased slightly. The LPO contents showed similar trends as CAT and GR, with slighter changes. However, MT levels were not significantly elevated with the extension of exposure time, suggesting their insensitivity to CAP. The results indicated that F. candida was a better indicator animal.The activities of CAT, GR and GST were sensitive to CAP exposure and could be used as potential biomarkers in CAP early warning. TG and LPO could be used as selective biomarkers for medium and long term CAP warning.