Department of Biology, University of Louisiana at Lafayette, Lafayette, LA 70504-2451, USA.
Ecotoxicology. 2010 Apr;19(4):654-61. doi: 10.1007/s10646-009-0437-8. Epub 2009 Nov 19.
Worldwide amphibian declines have been a concern for biologists for the past several decades. The causes of such declines may include habitat loss, invasive species, pathogens, and man-made chemicals. Agricultural herbicides, in particular, are known to interfere with reproduction in amphibians and are likely contributing to population declines. We tested the effects of the herbicide atrazine on developing spotted salamanders (Ambystoma maculatum) and their symbiotic green alga Oophila amblystomatis. We exposed spotted salamander egg masses to atrazine at concentrations of 0 microg/L (control), 50, 100, 200, and 400 microg/L. Algae were eliminated in all atrazine treatments. Hatching success was significantly lower for atrazine-treated egg masses than for the controls, and was inversely related to atrazine concentration. The highest developmental stage reached by the embryos was significantly lower in the atrazine treatments than in the controls, and was inversely related to atrazine concentration. These results indicate that atrazine exposure affected spotted salamanders both directly by causing pathologies and mortality in embryos and indirectly by eliminating their symbiotic alga.
全球范围内的两栖动物数量减少一直是过去几十年来生物学家关注的问题。造成这种减少的原因可能包括栖息地丧失、入侵物种、病原体和人为化学物质。农业除草剂尤其已知会干扰两栖动物的繁殖，并可能导致种群减少。我们测试了除草剂莠去津对发育中的斑点钝口螈（Ambystoma maculatum）及其共生绿藻 Oophila amblystomatis 的影响。我们将斑点钝口螈的卵块暴露在 0 微克/升（对照）、50、100、200 和 400 微克/升的莠去津浓度下。在所有莠去津处理中，藻类都被消灭了。与对照组相比，莠去津处理的卵块孵化成功率显著降低，且与莠去津浓度呈反比。在莠去津处理组中，胚胎达到的最高发育阶段明显低于对照组，且与莠去津浓度呈反比。这些结果表明，莠去津暴露不仅直接通过在胚胎中引起病变和死亡率，而且还通过消除其共生藻类间接影响斑点钝口螈。
