UV-B辐射增强对土生对齿藓(Didymodon vinealis)结皮生理代谢及光系统相关蛋白表达的影响  

Effects of enhanced UV-B radiation on physiological metabolism and photosystem-related protein expression of Didymodon vinealis (Brid.) Zand crust

作　　者：回嵘[1] 李新荣[1] 陈翠云[1] 赵锐明[2] 赵昕[1] 李培广[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所沙坡头沙漠试验研究站,植物逆境生理生态与生物技术实验室,兰州730000 [2]甘肃农业大学生命科学技术学院,兰州730070

出　　处：《生态学杂志》2013年第3期583-590,共8页Chinese Journal of Ecology

基　　金：中国科学院知识创新工程重要方向项目(KZCX2-EW-301-1);国家自然科学基金面上项目(41271061);国家自然科学基金重点项目(40930636)资助

摘　　要：以中国科学院沙坡头沙漠试验研究站人工固沙植被区的土生对齿藓(Didymodon vinealis(Brid.)Zand.)结皮为试验材料,通过室内模拟UV-B4个辐射强度[2.75(对照)、3.08、3.25和3.41W·m-2]的处理,研究了UV-B辐射增强对土生对齿藓结皮生理代谢及光系统相关蛋白表达的影响。结果表明:随着UV-B辐射强度增加,丙二醛(MDA)含量呈增加趋势;叶绿素a荧光诱导动力学参数、可溶性蛋白质及类囊体膜蛋白表达量随着辐射强度的增加而降低,且与辐射强度呈反比。模拟UV-B辐射增强促进了土生对齿藓结皮活性氧的代谢速率,导致了膜脂过氧化,可溶性蛋白质含量减少,进而降低PSII反应中心活性,最终导致光合作用能力下降,这一结果对于进一步理解生物土壤结皮对UV-B辐射的响应机制,探索应用生物土壤结皮进行荒漠化治理具有重要的理论与实践意义。Taking the Didymodon vinealis （ Brid. ） Zand crust from an artificial vegetation area of Shapotou Desert Research and Experiment Station in Northwest China as test object, a 10-day laboratory simulation experiment was conducted to study the effects of enhanced UV-B on the physiological metabolism and photosystem-related protein expression of the crust. Four UV-B treatments were installed, i. e. , 2.75 （CK） , 3.08, 3.25 and 3.41 W · m-2. With the increas- ing UV-B radiation, the malondialdehyde （MDA） content presented an increasing trend, while the chlorophyll a fluorescence-induced kinetics parameters and the water-soluble protein and thyl- akoid membrane proteins expression showed a continuous decrease, and the decrement was nega- tively proportional to the intensity of the UV-B radiation. The enhanced UV-B radiation acceler- ated the reactive oxygen species （ROS） metabolism rate, induced the lipid peroxidation, de- creased the water-soluble protein content, and further, reduced the activity of the reaction center of photosystem II （PSII）, leading to the decline of photosynthesis. This study would help us to further understand the response mechanisms of biological soil crust （BSC） under UV-B radiation,and have academic and practical significances for the BSC application in desertification areas .

关 键 词：土生对齿藓结皮 UV-B辐射 叶绿素a荧光诱导动力学参数 类囊体膜 蓝绿温和聚丙烯酰胺凝胶电泳(BN-PAGE) 

分 类 号：S154[农业科学—土壤学]