Hg^(2+)对玉米幼苗膜脂过氧化防御系统的影响

Effects of Hg 2+ on the Protective System of Membrane-Lipid Peroxidation in Maize Seedling

用控制营养液Ｈｇ２＋量（０ｍｇ／Ｌ，０．３ｍｇ／Ｌ，０．６ｍｇ／Ｌ）的方法培养玉米幼苗，得到３种Ｈｇ２＋水平的玉米幼苗叶片为材料，研究不同Ｈｇ２＋水平对玉米幼叶膜透性及其膜脂过氧化防御系统的影响．结果表明：经Ｈｇ２＋处理的玉米幼叶膜相对透性和丙二醛含量显著上升；ＳＯＤ活性呈“先上升后下降”趋势；而ＰＯＤ，ＣＡＴ活性呈明显下降趋势，且０．６ｍｇ／ＬＨｇ２＋处理的各项指标变化幅度均大于０．

In order to probe the roles of Hg 2+ in plants,the maize seedlings grown in the solutions with different Hg 2+ concentrations (0,0.3,0.6mg/L) were used to study the effects of Hg 2+ on plasmamembrane realitive permeability (RP),membrane-lipid peroxidation protective system.The results showed that the RP and MDA contents in the maize seedlings treated with Hg 2+ increased strikingly,and the activity of SOD in the maize seedlings treated with Hg 2+ showed ‘increasing before decreasing’.However,under Hg 2+ treatment,the activities of POD and CAT all dropped largely,and all above indexes treated with 0.6mg/L Hg 2+ changed much more than those with 0 3mg/L Hg 2+ .