镉污染下芦苇叶片丙二醛、脯氨酸及SOD保护酶反应研究

Reaction of MDA,Proline,and SOD under Cd stress in mixture of Phragmites australis's stems and leaves

选择湿地芦苇为研究材料,设置0、0.01、0.2、2、4mg/L 5个浓度梯度的镉(Cd)处理,探讨在重金属Cd污染条件下,芦苇地上部分的生理响应及抗性表现。结果表明:在不同Cd2+浓度梯度下,芦苇体内丙二醛(MDA)、脯氨酸含量及SOD酶活性均产生明显变化,随Cd2+浓度升高,MDA含量急剧上升,至0.01mg/L时达最高值,随即下降,至2mg/L又开始上升;而SOD酶则总体呈逐渐上升的趋势,只在4mg/L时略有下降;脯氨酸含量显著上升,但当Cd2+浓度超过0.2mg/L时其含量下降;通过对在重金属镉污染生境下芦苇地上部分的生理研究表明,芦苇细胞结构受到了明显的伤害,突出表现为细胞膜结构的过氧化程度加剧;而在此逆境下,芦苇也表现出了明显的抗性反应,即渗透调节物质脯氨酸含量的上升和SOD酶活性的显著增加,且三者之间存在着一定的交互作用。

We selected wetland plant -Phragmites attstralis as study materials, and provided five levels of Cd stress （0,0.01,0.2,2,4mg/L） in order to probe into physiological response of aerial parts of Phragmites austra- 1/s and resistance under the cadmium pollution conditions. The research indicated that content of MDA and Pro- line, and the activity of SOD changed distinctly under Cd stress. With the concentration of Cd increased, content of MDA gradually increased first and reach the highest value at 0.01mg/L, and then decreased afterwards at 2mg/L, and increased again. The activity of SOD gradually increased, and only declined slightly at 4mg/L. Content of Proline gradually increased first and decreased afterwards when the concentration of Cd exceed 0. 2mg/L. The results indicated that Cd stress made Phragmites australis＇cellular structure significantly damaged, and especially made the peroxidation of cellular structure worsen. On the other hand, the antioxidant system in Phragmites australis had been activated under Cd stress creasing of Proline content and SOD activity, and there to eliminate the active oxygen, which expressed by in- was a certain interaction among the three elements.