3种酰胺类除草剂对斑马鱼不同生长阶段的急性毒性效应

为探明酰胺类除草剂对鱼类不同生长阶段的毒性效应,分别以斑马鱼胚胎、8日龄仔鱼、55日龄幼鱼和3月龄成鱼为受试对象,研究3种酰胺类除草剂乙草胺、丙草胺和丁草胺对斑马鱼(Danio rerio)不同生长阶段的毒性效应。研究发现,高浓度乙草胺、丙草胺和丁草胺均可抑制斑马鱼胚胎的孵化。乙草胺对斑马鱼胚胎、仔鱼、幼鱼和成鱼的96 h-LC50值分别为5.82、1.34、3.00、1.44 mg·L-1,毒性从高到低顺序依次为:仔鱼成鱼幼鱼胚胎。丙草胺对斑马鱼胚胎、仔鱼、幼鱼和成鱼的96 hLC50值分别为2.79、2.02、2.26、2.01 mg·L-1,毒性从高到低顺序依次为:仔鱼、成鱼幼鱼胚胎。丁草胺对斑马鱼胚胎、仔鱼、幼鱼和成鱼的96 h-LC50值分别为1.73、0.919、3.37、1.19 mg·L-1,毒性从高到低顺序依次为:仔鱼成鱼胚胎幼鱼。研究结果表明,酰胺类除草剂对斑马鱼4个典型生长阶段的毒性差异较大,仔鱼阶段对酰胺类除草剂最敏感,成鱼其次。

Acute Toxicity Effects of Three Amide Herbicides to Different Life Stages of Zebrafish (Danio rerio)

To explore the toxic effects of amide herbicides on fish, the differences in acute toxicity of three amide herbicides (acetochlor, pretilachlor and butachlor) to different life stages of zebrafish (Danio rerio) were evaluated. The results displayed that the hatching of zebrafish embryos were inhibited by high concentrations of acetochlor, pretilachlor and butachlor. The 96h-LC50 values of acetochlor to the embryo, larvae, juvenile and adult of zebrafish were 5.82, 1.34, 3.00 and 1.44 mg·L-1, respectively. The acute toxicity of acetochlor to zebrafish at different life stages was in the order larva>adult>juvenile>embryo. For the acute toxicity of pretilachlor to the zebrafish embryo, larvae, juvenile and adult, the 96 h-LC50 values were 2.79, 2.02, 2.26 and 2.01 mg·L-1, respectively. The trend of acute toxicity was larva and adult>juvenile>embryo. The 96 h- LC50 values of butachlor to embryo, larvae, juvenile and adult of zebrafish were 1.73, 0.919, 3.37 and 1.19 mg·L-1, respectively. And the trend of acute toxicity was: larva>adult> embryo> juvenile. The results demonstrated that zebrafish at different life stages exhibited different levels of sensitivity to amide herbicides, and larvae was the most sensitive stage to amide herbicides, followed by adult.