不同盐度对苦草生理特征的影响  

Effect of different salinity on physiological features of Vallisneria natans

作　　者：刘晓培[1] 张饮江[1,2] 李岩[1] 董悦[1] 易冕[1] 文晓峰[1] 

机构地区：[1]上海海洋大学水产与生命学院,上海201306 [2]水域环境生态上海高校工程研究中心,上海201306

出　　处：《生态科学》2012年第6期606-612,共7页Ecological Science

基　　金：国家水专项(08ZX07101-005);国家科委世博专项(05ba908b23);上海市科学技术委员会重大项目(08dx1900408);上海市重点学科建设项目(Y1110;S30701)

摘　　要：沉水植物耐盐性研究越来越受到人们高度重视。在室内模拟条件下,水体盐度设为2、3、4、5、6和8,及不加盐卤的对照组(记为0),每24 h测定苦草(Vallisneria natans)叶片叶绿素含量,SOD、POD和CAT 3种抗氧化酶活性,MDA含量及呼吸强度。结果表明:叶绿素a、叶绿素b含量和CAT酶活性随盐度增加呈降低趋势;SOD、POD酶活性、MDA含量随盐度增加呈先升后降趋势;盐度为2和3时叶绿素含量、抗氧化酶酶活性、MDA含量和呼吸强度与对照组相比差异性不显著(P>0.05),苦草生长状态较其它处理组好;盐度为4时,所测叶绿素含量、抗氧化酶活性和呼吸强度与对照组相比差异性显著(P<0.05),叶绿素含量明显降低,抗氧化酶活性升高,表现出了明显的抗逆性,呼吸强度降低;盐度为5、6和8时与对照组相比,苦草生长状态较差,并逐步枯萎,第4 d死亡。因此苦草可应用于盐度低于3水体中沉水植被的恢复与重建。People have paid more and more attention to the salt tolerance of submerged plants recently.The content of chlorophyll a in the leaves,the activity of SOD,POD and CAT,the MDA content and the respiration intensity of Vallisneria natans at every 24 hours were tested in laboratory simulation condition,with salinity gradients of 0(the control group),2,3,4,5,6 and 8.The results showed that chlorophyll a,chlorophyll b and CAT activity decreased with the increase of salinity;the enzyme activity of SOD and POD,and the MDA content increased firstly and then dropped with the increasing salinity.Chlorophyll content,the enzyme activity of antioxidant enzymes,MDA content and respiration intensity index in salinities 2 and 3 were not significantly different from those in the control group(p>0.05),and V.natans grew better than other treatment groups.There were significant differences(p<0.05) in chlorophyll content,the enzyme activity of antioxidant enzymes,MDA content and respiration intensity index between the treatment group of salinity 4 and the control group.The chlorophyll content decreased obviously,antioxidant enzymes activity increased and showed an obvious resistance,and respiration intensity reduced.The growth of V.natans in the treatment groups of salinities 5,6 and 8 was worse than in the control group,and V.natans withered gradually and finally were dead on the forth day.As a result,V.natans can be used in the submerged vegetation restoration and reconstruction under the water salinity less than 3.

关 键 词：苦草 盐度 叶绿素 酶活性 呼吸强度 

分 类 号：X173[环境科学与工程—环境科学]