遮荫和氮养分对三裂叶蟛蜞菊生长、构件生物量分配和叶片PSⅡ功能的影响  

Effects of shade and nutrient level on plant growth, module biomass allocation and PSⅡ functions of Wedelia trilobata

作　　者：陈文[1] 王桔红 朱慧 吴晓蓉 颜玉娟 汪翠丽 CHEN Wen;WANG Juhong;ZHU Hui;WU Xiaorong;YAN Yujuan;WANG Cuili(College of Geography and Tourism Management,Hanshan Normal University,Chaozhou 521041,Guangdong,China;College of Food Technology and Life Science,Hanshan Normal University,Chaozhou 521041,Guangdong,China;Central South University of Forestry and Technology,Shangsha 410000,Hunan,China)

机构地区：[1]韩山师范学院地理与旅游管理学院,潮州521041 [2]韩山师范学院食品工程与生物科技学院,潮州521041 [3]中南林业科技大学风景园林学院,长沙410004

出　　处：《生态科学》2018年第4期160-167,共8页Ecological Science

基　　金：国家自然科学基金项目(31770584);广东省科技发展专项资金(2016A030303063)

摘　　要：为探查外来入侵植物三裂叶蟛蜞菊(Wedelia trilobata)对遮荫和氮养分的响应及其入侵性,采用盆栽实验研究了遮荫(轻度遮荫-相对光强为42%;重度遮荫-相对光强为12%)和不同氮养分(0、0.1、0.2和0.4 g·kg^(–1))对三裂叶蟛蜞菊生长、生物量分配以及叶片PSⅡ功能的影响。结果表明:1)经轻度遮荫的植物叶片数、分枝数、总生物量、生长速率显著大于重度遮荫;同一遮荫条件下,随氮养分的增加,茎生物量比增加、叶生物量比下降。2)重度遮荫降低了三裂叶蟛蜞菊叶片实际光化学效率(ФPSⅡ)和表观光合电子传递速率(ETR),对叶片PSⅡ反应中心有一定破坏作用;对最大光化学量子产量(Fv/Fm)的影响不显著(除0.2 g·kg^(–1)氮水平外)。3)氮养分对叶片PSⅡ活性的影响随遮荫程度而变化,轻度遮荫下,氮养分对叶片PSⅡ功能影响较小;重度遮荫下,随氮养分的增加,ФPSⅡ和ETR先上升后下降,Fv/Fm变化不显著。4)光强和氮养分的交互作用在三裂叶蟛蜞菊种群生长、竞争以及成功入侵过程中发挥着重要作用,在光照较充足的生境中容易成功入侵。In order to research the response of alien species Wedelia trilobata to shading condition and nitrogen nutrient and further to reveal the invasion, the effects of shade and nutrient levels on plant growth, biomass allocation patterns, and PSⅡ functions of invasive W. trilobata were studied by using a series of greenhouse pot experiment. Two shading conditions and four nitrogen level were set up with relative light intensity of 42%（mild shade） and of 12%（heave shade）, and with nitrogen level of 0, 0.1, 0.2, and 0.4 g·kg^-1. The results showed that shading condition and nutrient levels have important influence on plant growth, biomass allocation patterns in varying degrees, except for plant height. Under the various nitrogen levels, the leaf number, branching number, total biomasses and relative growth rate in mild shade were significantly greater than those in heave shade. Under the same shading condition, stem biomass increased, while leaf biomass decreased with increasing of nutrient concentration. In addition, under heave shade conditions, the actual photochemical efficiency of PSⅡ（ФPSⅡ） and photosynthetic electron transport rate（ETR） decreased, minimum fluorescence（F0） increased, the value of the maximal quantum yield of PSⅡ（Fv/Fm） had no or less change comparison with the mold shade, implying low light level might have some damage for PSⅡ functions. The effects of nitrogen level on the leaf PSⅡ functions varied with the degree of shade. Under mold shading condition, the nitrogen level had no or less influence on leaf PSⅡ functions, but under heave shade the ФPSⅡand ETR first increased, then decreased with increasing of nitrogen level; the value of Fv/Fm had no or less change. The interaction effect of light intensity and nitrogen nutrient play an important role on growth, competition and invading of W.trilobata, in which light intensity is the dominant factor. It is easier to invade for W.trilobata in habitats with sufficient light than in heavy shade habitat.

关 键 词：三裂叶蟛蜞菊 遮荫 氮养分 生长特性 PSⅡ功能 

分 类 号：Q142.9[生物学—生态学]