氮、磷养分对飞机草营养器官表型可塑性的影响  

Effects of nitrogen and phosphorus nutrients on the nutritive organ phenotypic plasticity of invasive Chromolaena odorata

作　　者：全国明[1,2] 谢俊芳[1] 章家恩[1] 毛丹鹃[1] 

机构地区：[1]华南农业大学热带亚热带生态研究所/农业部华南热带农业环境重点实验室/广东省高等学校农业生态与农村环境重点实验室,广州510642 [2]广州城市职业学院城市建设工程系,广州510405

出　　处：《生态学杂志》2014年第10期2625-2632,共8页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(U1131006);国家星火计划项目(2013GA780108);教育部博士点基金项目(20124404110009);广东省高等学校高层次人才项目(粤教师函[2010]79号;粤财教[2013]246号);广州市属高校科研计划项目(2012A136)资助

摘　　要：采用温室盆栽试验研究了不同氮、磷水平对入侵植物飞机草(Chromolaena odorata)营养器官表型可塑性的影响。结果表明:随着氮、磷水平的上升,飞机草的分枝数量、分枝长度、叶片数、总叶面积、总生物量以及茎、叶器官生物量显著增加。飞机草的根生物量比、根冠比随着氮、磷水平的升高显著下降;茎生物量比在供氮(磷)量达0.05 g·kg-1时显著增加,之后保持稳定;叶生物量比随氮水平的增加先降后升,但其受磷水平变化的影响较小。叶面积比、叶根比、比叶面积和平均相对生长速率随着氮、磷水平的上升显著增加,但叶面积比、叶根比和比叶面积在供磷量≥0.05 g·kg-1时的差异不明显。飞机草的分枝数量、分枝长度、叶片数、总叶面积、根生物量比、根冠比、叶根比以及茎、叶与植株总生物量等指标的可塑性指数较高,并且对氮素的响应更强。表明氮、磷水平能够显著影响飞机草的植株生长,飞机草亦能够通过植株形态、结构以及生物量积累与分配的调整来适应多变的养分环境,并表现出较高的可塑性。The effects of different nitrogen and phosphorus levels on the nutritive organ pheno- typic plasticity of invasive Chromolaena odorata were studied by a greenhouse pot experiment. The results showed that branch number, branch length, total leaf number, total leaf area, total biomass, stem biomass and leaf biomass of C. odorata increased significantly with the increase of nitrogen and phosphorus levels. The ratio of root biomass to aboveground biomass decreased sig- nificantly with the increasing nitrogen and phosphorus levels, while the stem biomass fraction in- creased notably at 0.05 g ～ kg-t of nitrogen or phosphorus treatments and remained stable there- after. Leaf mass fraction reduced first and then increased remarkably with the increasing nitrogen level, but it was less affected by the phosphorus levels. Leaf area ratio, the ratio of leaf area to root mass, specific leaf area and relative growth rate of C. odorata increased significantly with the increasing nitrogen and phosphorus levels, but had no differences when the phosphorus levels were ≥0.05 g · kg-I except the relative growth rate. Phenotypic plasticity indexes of branch number, branch length, total leaf number, total leaf area, total biomass, stem biomass, leaf bio- mass, root mass fraction, the ratios of root biomass to aboveground biomass and leaf area to root biomass of C. odorata were higher than that of other parameters, and the phenotypic response to nitrogen nutrient was also stronger than that to phosphorus. The results indicated that nitrogen and phosphorus levels had significant effects on the growth of C. odorata. C. odorata could modify its morphology, structure, biomass accumulation and allocation to adapt to the changing nutrient conditions, and thus demonstrated a strong phenotypic plasticity in response to different nitro- gen and phosphorus nutrient levels.

关 键 词：生物入侵 飞机草 氮 磷 表型可塑性 

分 类 号：Q948[生物学—植物学]