两种生境条件下6种牧草叶绿素含量及荧光参数的比较  

Comparison of chlorophyll content and fluorescence parameters of six pasture species in two habitats in China

作　　者：李磊[1,2,3] 李向义[1,3] 林丽莎[1,3] 王迎菊[1,2,3] 薛伟[1,2,3] 

机构地区：[1]中国科学院新疆生态与地理研究所,乌鲁木齐830011 [2]中国科学院研究生院,北京100049 [3]新疆策勒荒漠草地生态系统国家野外科学观测试验站,新疆策勒848300

出　　处：《植物生态学报》2011年第6期672-680,共9页Chinese Journal of Plant Ecology

基　　金：新疆维吾尔自治区科技计划项目(20093-3125);国家科技支撑计划(2009BAC54B03);国家重点基础研究发展计划(2009CB421303)资助

摘　　要：昆仑山前山牧场海拔较高,策勒绿洲海拔相对较低,两者生境差异较大。以昆仑山前山牧场和策勒绿洲边缘两种不同生境条件下生长的6种牧草:冰草(Agropyron cristatum)、无芒雀麦(Bromus inermis)、矮生高羊茅(Festuca elata)、披碱草(Elymus dahuricus)、红豆草(Onobrychis pulchella)及和田大叶(Medicago sativa var.luxurians)为试验材料,研究了不同生境条件下牧草叶片叶绿素含量及叶绿素荧光动力学参数的变化情况。结果显示:(1)在两种生境条件下,昆仑山前山牧场生境生长的牧草叶绿素a、叶绿素b、总叶绿素的含量明显较高,生长在策勒绿洲生境的牧草品种叶绿素a/b值较高;(2)昆仑山前山牧场生境牧草最大荧光、光系统II(PSII)最大光化学效率、PSII潜在活性和单位面积反应中心的数量的值明显高于策勒绿洲生境品种,而初始荧光、单位反应中心吸收的光能、单位反应中心捕获的能量、单位反应中心耗散的能量、荧光诱导曲线初始斜率值则低于策勒绿洲生境品种。因此,两种生境下环境因子发生了改变,对牧草产生综合的胁迫作用;策勒绿洲生境明显对牧草生长产生了抑制,策勒绿洲生境牧草的色素含量降低以及PSII的机构遭到损坏,导致反应中心一部分失活或裂解,剩余有活性的反应中心的效率增加,昆仑山生境则相对比较适宜牧草生长;两种生境不同牧草叶绿素含量和叶绿素荧光参数的变化幅度不同。Aims Qianshan Pasture in the Kunlun Mountains and Cele Oasis of China are different habitats with different elevations. We compared six pasture species in terms of chlorophyll （Chl） content and fluorescence parameters to investigate the effect of habitat on photosystem II （PSII）. Methods Agropyron cristatum, Bromus inermis, Festuca elata, Elymus dahuricus, Onobrychis pulchella and Medicago sativa var. luxurians, were grown in both sites. Leaf pigment content was measured by 95% ethanol method, and PSII chlorophyll fluorescence parameters were monitored by using a Plant Efficiency Analyzer （PEA）. Important findings The measured physiological parameters differed greatly in all six species growing in the two habitats. In Qianshan Pasture, all species showed obviously higher Chl a, Chl b and total Chl content, while those growing in Cele Oasis had higher Chl a/Chl b. Plants in Kunlun Mountains also had markedly higher maximum fluorescence yield （Fm）, maximum photochemical efficiency of PSII （Fv/Fm）, potential activity of PSII （Fv/Fo） and active reaction centers per cross-section （RC/CSo）, as well as lower minimum fluorescence yield （Fo）, absorption flux per reaction center （ABC/RC）, maximal trapping flux per reaction center （TRo/RC）, flux of dissipated excitation energy per reaction center （DIo/RC） and initial slope of fluorescence intensity （Mo） than those in the Cele Oasis. These parameters also showed large differences in variation amplitude between habitats. The results indicated that environmental conditions in the Cele Oasis were stressful to pasture species. It decreased chlorophyll content and inactivated PSII. The habitat in Kunlun Mountains was relatively favorable for these species.

关 键 词：叶绿素 叶绿素荧光参数 生境 牧草 

分 类 号：S54[农业科学—作物学]