川蔓藻和蓖齿眼子菜对再生水中盐度的响应机制

通过在不同盐度再生水中培养川蔓藻和蓖齿眼子菜,研究了它们的生物量、光合强度及其组织中的脯氨酸、丙二醛、过氧化氢酶和叶绿素的含量变化对再生水中盐度的响应.结果表明不同盐度下川蔓藻和蓖齿眼子菜组织中累积的脯氨酸含量随时间呈指数增长;当盐度为10.07 g/L时,蓖齿眼子菜的丙二醛的含量显著上升,而过氧化氢酶的含量明显下降(p＜0.05),氧自由基产生和消除之间的平衡被破坏;当盐度超过7.72 g/L时,川蔓藻和蓖齿眼子菜中叶绿素和叶绿素a/b值均显著下降,但川蔓藻能通过增加叶绿素b来补偿盐度对光合作用效率的影响.川蔓藻和蓖齿眼子菜均能通过调节自身的脯氨酸代谢和抗氧化系统来抵抗再生水中盐度的胁迫,且川蔓藻在高盐胁迫下具有较好的清除氧自由基能力.

Response Mechanism of Ruppia Maritima and Potamogeton Pectinatus to Salinity in Reclaimed Wastewater

The biomass photosynthesis activity of Ruppia maritima and Potamogeton pectinatus and the proline,malondialdehyde(MDA),catalase(CAT),and chlorophyll contents in their leaf-tissues in response to salinity were studied by investigating the plants cultured with reclaimed wastewater of different salinities.The results show that proline content in tissues of R.maritima and P.pectinatus increases exponentially with time at different salinities.When the salinity is 10.07 g/L,MDA content in tissues of P.pectinatus increases significantly but catalase content decreases significantly(p<0.05),and the balance between producing and removing of free oxygen radicals is damaged.When the salinity exceeds 7.72 g/L,the chlorophyll and chlorophyll a/b value in R.maritima and P. pectinatus decrease,but R.maritimcan counteracts salinity impact on photosynthesis efficiency through increasing chlorophyll b.All these results imply that R.maritima and P.pectinatus can both resist the salt stress through adjusting their own proline metabolism and inoxidizable system,and R.maritima has better ability to remove free oxygen radicals in high-salt stress.