斜生栅藻对乙酰甲胺磷的急慢性毒性响应

为了解有机磷农药乙酰甲胺磷污染对本土水生敏感性物种斜生栅藻(Scenedesmus obliquus)的毒性效应,在实验室条件下采用静态毒性试验,研究了乙酰甲胺磷对斜生栅藻96 h急性毒性效应,并在急性试验基础上进行慢性试验,分析了斜生栅藻连续染毒14 d的叶绿素质量浓度、可溶性蛋白质量分数以及丙二醛(MDA)质量摩尔浓度的变化.结果表明:乙酰甲胺磷的96 h EC₅₀为482.9 mg/L,属低毒农药,但在1 mg/L低质量浓度下可促进藻细胞生长;乙酰甲胺磷对栅藻光合作用无明显影响,但可通过干扰藻细胞代谢活动和引起膜脂过氧化反应,对斜生栅藻产生毒性作用;可溶蛋白和MDA可作为有效的生物标志物对农药引起的毒性做出评价.研究结果可为本土水生敏感性物种的保护和农药安全使用标准的制定提供理论依据.

Acute and chronic response of Scenedesmus obliquus to acephate

In order to understand the toxic effects of the pollution by organophosphorus pesticide as acephate on the local aquatic sensitive species as Scenedesmus obliquus,under laboratory conditions,based on the static toxicity test,the acute toxic effects of acephate on Scenedesmus obliquus for 96 hours were investigated in this paper.And based on the acute test,the chronic experiments including the 14 days changes of chlorophyll a,soluble protein and MDA in Scenedesmus obliquus were analyzed.It shows that:the 96 h EC₅₀of acephate is 482.9 mg/L,which belongs to the low-toxic pesticide and the growth of Scenedesmus obliquus could be promoted with 1 mg/L of acephate;no significant effect is showed on the photosynthesis of Scenedesmus obliquus,but the toxic effects are exposed by acephate through interfering the algae''s metabolic activities and causing membrane lipid peroxidation;the soluble protein and MDA could be used as valid biological markers for evaluating the toxicity of pesticide.The results in this paper could be considered as the theoretical basis for protecting local aquatic sensitive species and establishing the criterion on safe use of pesticide.