3个树种对不同程度土壤干旱的生理生化响应  

Physiological and biochemical responses to different soil drought stress in three tree species

作　　者：吴芹[1] 张光灿[1] 裴斌[1] 方立东[1] 

机构地区：[1]山东省土壤侵蚀与生态修复重点实验室/山东农业大学林学院/国家林业局泰山森林生态站,泰安271018

出　　处：《生态学报》2013年第12期3648-3656,共9页Acta Ecologica Sinica

基　　金：国家林业公益性行业科研专项(201104068);国家重点基础研究发展计划(973计划)项目(2012CB416904);国家自然科学基金资助项目(30872003)

摘　　要：利用盆栽试验和采用人工浇水后持续自然耗水的方法,研究了3年生山杏(Prunus sibirica)、沙棘(Hippophae rhamnoides)、油松(Pinus tabulaeformis)对土壤干旱胁迫的生理生化响应过程。结果表明:随着干旱程度加剧,3个树种叶片相对含水量(LRWC)及叶绿素(Chl)含量持续下降,细胞膜透性逐渐增大;其中,以山杏和沙棘变化幅度较大,油松最小;3个指标发生显著变化的土壤相对含水量(RWC)临界值,油松为54.7%、山杏和沙棘分别为46.7%和48.4%。3个树种超氧化物歧化酶(SOD)与过氧化物酶(POD)两种抗氧化酶活性,随RWC降低先升高后降低;维持较高抗氧化酶活性的RWC范围,油松为32.9%—76.4%、山杏和沙棘分别为46.7%—77.9%和35.8%—78.2%;在不同土壤干旱程度下,油松的抗氧化酶活性水平高于沙棘和山杏。3个树种两种渗透调节物质脯氨酸(Pro)与可溶性糖(Ss)的含量随RWC降低而增加,油松的增加幅度大于山杏和沙棘;Pro含量的增加速度大于Ss含量。结论:3个树种可通过渗透调节、抗氧化酶活性升高等途径增强对干旱逆境的耐受性和适应性;3个树种的抗旱能力为油松>沙棘>山杏。Water deficiency plays an important role in plant growth and metabolism. Response and adaptation to drought stress has become one of the hotspots of plant physiological research. Prunus sibirica, Hippophae rhamnoides and Pinus tabulaeformis are common afforestational tree species in arid and semi-arid region of North China. However, changes of the physiological and biochemical responses to different soil drought stress and their drought resistance are not clear at present. The objective of this study is to explore the quantitative relationship of the changes of the physiological and biochemical indexes and the soil moisture and to evaluate the drought-resistant ability of the three tree species. It will help us to further understand their physiological and ecological characteristics of the water and drought-resistant physiology. The results will also provide guidance for the cultivation of the three tree species in arid area. The physiological and biochemical responses of three-year-old of P. sibirica, H, rhamnoides and P. tabulaeformis to soil drought stress were investigated by natural drought method. The results showed that leaf relative water content （LRWC） and the chlorophyll （Chl） content decreased while the cell membrane permeability increased gradually in the three tree species following the relative water content （ RWC ） of soil reduced. The changes of the tested responses in P. sibirica andH. rhamnoides were bigger than those in P. tabulaeformis. LRWC, Chl content and the cell membrane relative permeability changed significantly when the soil RWC were lower than 54.7% , 46.7% , and 48.4% for P. tabulaeformis, P. sibirica and H. rhamnoides, respectively. Superoxide dismutase （SOD） and peroxidase （POD） which are the most important protective enzymes to eliminate reactive oxygen species （ROS） maintain higher activity to prevent ROS poisoned. The activity of SOD and POD in the three tree species increased first and then decreased following the soil water reduced. The response time a

关 键 词：抗旱生理 水分胁迫 抗氧化酶活性 渗透调节 抗旱评价 

分 类 号：S714[农业科学—林学]