Schmidt G H, Ibrahim N M, Abdallah M D
Department of Zoology-Entomology, University of Hannover, FRG.
Sci Total Environ. 1991 Sep;107:109-33. doi: 10.1016/0048-9697(91)90254-c.
Long-term effects of soil treated with 0.12-12 ppm HgCl2, 2-100 ppm CdCl2 and 25-500 ppm PbCl2 on the development, reproductive capacity and viability of Aiolopus thalassinus (Fabr.) (grasshoppers) during two successive generations were studied. The hatching rate of nymphs developed from eggs laid in treated soil was significantly reduced. Mercury was the most effective in reducing the hatching rate followed by cadmium and lead. The newly hatched nymphs, which developed in the heavy-metal-treated soil, were transferred to and reared in separate cages in order that toxicological effects could be followed through the next two generations without any further treatment. No significant increase was observed in percent mortality during both the F1 and F2 nymphal stages resulting from Hg, Cd and Pb treatment. The nymphs were more tolerant than the eggs and adults to the cumulative effect of heavy metals. The mean durations of the F1 and F2 nymphal stages were prolonged in all Hg and Cd treatments, but such a prolongation in the Pb treatments was found only in F1 nymphs, those developed from the two highest soil PbCl2 concentrations (250 and 500 ppm). The adult fresh weight of the F1 and F2 generations was significantly low in the case of the Hg and Cd treatments. The lifespan of the F1 and F2 adults developed from eggs laid in Hg-, Cd- and Pb-treated soil was significantly shortened and thus the number of egg pods was reduced in comparison with the control. The hatchability of nymphs developed from eggs laid by the F1 generation was significantly lower than that of the untreated control. No significant decrease in the hatching rate was found for the eggs laid by the F2 generation, except at the highest soil concentrations of the three metals. The metal content of eggs laid by the F1 generation increased significantly with increasing soil concentrations of the three metals. In the F2 generation eggs the heavy metal content was reduced in all cases; this indicates a dilution of the metal concentration in successive generations if no further exposure takes place.
研究了用0.12 - 12 ppm HgCl₂、2 - 100 ppm CdCl₂和25 - 500 ppm PbCl₂处理的土壤对两代连续的黄胫小车蝗（Fabr.）（蝗虫）发育、繁殖能力和生存能力的长期影响。在经处理土壤中产卵孵化出的若虫孵化率显著降低。汞对降低孵化率最为有效，其次是镉和铅。将在重金属处理土壤中发育的新孵化若虫转移到单独的笼子中饲养，以便在不进行任何进一步处理的情况下跟踪接下来两代的毒理学效应。汞、镉和铅处理导致的F1和F2若虫阶段死亡率百分比均未显著增加。若虫比卵和成虫对重金属的累积效应更具耐受性。在所有汞和镉处理中，F1和F2若虫阶段的平均持续时间延长，但仅在F1若虫中发现铅处理有这种延长，这些若虫来自土壤中PbCl₂浓度最高的两个水平（250和500 ppm）。在汞和镉处理中，F1和F2代成虫的鲜重显著降低。由在汞、镉和铅处理土壤中产卵发育而来的F1和F２代成虫寿命显著缩短，因此与对照相比，卵荚数量减少。F1代产卵孵化出的若虫孵化率显著低于未处理对照。F2代产卵除在三种金属的土壤最高浓度下外，未发现孵化率有显著下降。F1代产卵的金属含量随土壤中三种金属浓度的增加而显著增加。在F2代卵中，所有情况下重金属含量均降低；这表明如果不再接触，连续几代中金属浓度会被稀释。
