抗氧化剂对渗透胁迫下沙棘叶片膜脂过氧化的保护作用

Effect of Anti-oxidation Marttor to Protective Function on Cell Membrane of Seabuckthorn Leaf under PEG Osmotic Stress

以沙棘叶片为材料 ,研究了外源抗氧化物质 Vc、VE、β-胡萝卜素等对 PEG渗透胁迫下细胞膜的保护作用。结果表明 :加入外源 Vc、β-胡萝卜素能有效保护膜系统 ,使膜透性和丙二醛在胁迫条件下增加小于对照 ,尤其在胁迫前期作用明显 ,而对叶绿素的保护作用在后期表现更突出 ,使叶绿素含量维持在较高水平 ;外源 VE 对防止膜透性增加作用不大 ,对减低丙二醛含量与保护叶绿素方面有所贡献。同时也证明沙棘叶片内 Vc在渗透胁迫下含量下降 ,而 Pro含量显著升高。证明这些物质是构成沙棘抗旱性的重要基础。

The protective function of exogenous anti oxidation matter including Vc、V E and β carotene on cell membrane of seabuckthorn leaf under PEG osmotic stress was analyzed.The results showed that applied exodenous Vc and β carotene could protect membrane system from osmotic stress effectively, which displayed that the range of increasment of membrane permeability and MDA content were lower that of control.The protective effect was significant especially at early stage of osmotic stress.While the protective function on chlorophyll was prominent at later stage and chlorophyll content was kept in higer level all along; exogenous V E had a little effect on the avoidance of the increasement of membrane permeability.On the other hand, it contributed to the reduction of MDA content and the protection of chlorophyll.Vc content of seabuckthorn leaf declined while Pro content increased evidently under osmotic stress were also tested .It is proved that these materials were the important factor in constitution of drought resistance capability of seabuckthorn.