氮胁迫对水曲柳幼苗养分吸收、利用和生物量分配的影响

摘要/Abstract

摘要： 树木受到环境胁迫时发生形态和生理上的改变,以便获取对其生长发育限制最严重的资源.在东北林区凋落物因受温度影响分解速度和有机物矿质化过程缓慢,森林树木常受到氮营养胁迫.通过温室栽培试验,对氮胁迫下水曲柳幼苗生长的生理学和形态学指标进行了研究.结果表明,在氮胁迫下,水曲柳幼苗的净氮吸收速率和净磷吸收速率都会减少,但在生长前期氮利用效率和磷利用效率高于氮供给充足(8 mmol·L^-1)和过量(16 mmol·L^-1)时的氮利用效率和磷利用效率.当氮供给浓度不足时,叶重比减少,而特定叶面积和根重比增加.相对生长速率随氮供给浓度增加而增加.在氮胁迫下净同化速率下降,导致总生物量下降.在幼苗生长前期,水曲柳幼苗处于氮胁迫时根/茎比显著大于氮供给充足或过量时的根/茎比,而在生长后期,根/茎比没有显著差别.

关键词: 氮胁迫, 养分吸收与利用, 生物量分配, 水曲柳

Abstract: Under environmental stresses,trees often change their morphological and physiological components to acquire the most limited resources.In northeastern forest region of China,the decomposition and mineralization of litters occur slowly due to low temperature,which often results in forest trees suffering from nutritional stress.With pot culture in greenhouse,this paper studied the effects of nitrogen stress on the physiological and morphological components of Fraxinus mandshurica seedlings.The results showed that under N stress,the net uptake rate of nitrogen and phosphate by the seedlings decreased,while their nitrogen and phosphate use efficiency were higher than those of the seedlings supplied with 8 mmol稬^-1 or 16 mmol稬^-1 of nitrogen during the early growth stage.When suffering from N stress,the leaf mass ratio of the seedlings reduced,with specific leaf area and root mass ratio increased.The relative growth rate increased with the increasing N concentrations supplied to the seedlings during the whole growth period.Under N stress,the net assimilation rate decreased,which resulted in the decrease of total biomass,and the root/shoot ratio was significantly higher than that of the seedlings supplied with 8 mmol稬^-1 or 16 mmol稬^-1 of nitrogen during the early growth stage.There was no significant difference during the late growth stage.

Key words: Nitrogen stress, Nutrient uptake, Biomass distribution, Fraxinus mandshurica

中图分类号:

吴楚, 王政权, 范志强, 孙海龙. 氮胁迫对水曲柳幼苗养分吸收、利用和生物量分配的影响[J]. 应用生态学报, 2004, (11): 2034-2038.

WU Chu, WANG Zhengquan, FAN Zhiqiang, SUN Hailong . Effects of nitrogen stress on nutrient uptake by Fraxinus mandshurica seedlings and their biomass distribution[J]. Chinese Journal of Applied Ecology, 2004, (11): 2034-2038.

参考文献

[1] Agren GI,Ingestad T.1987.Root:shot ratio as balance between nitrogen productivity and photosynthesis.Plant Cell Environ,10:579～586
[2] Aphalo PJ,Leto T.1997.Effects of light quality on growth and N accumulation in birch seedlings.Tree Physiol,17:125～132
[3] Bloom AJ,Chapin FS Ⅲ,Mooney HA.1985.Resource limitation in plants-An economic analogy.Ann Rev Ecol Syst,16:363～392
[4] Broadley MR,Escobar-Gutiérrez AJ,Burns A,et al.2000.What are the effects of nitrogen deficiency on growth components of lettuce? New Phytol,147:519～526
[5] Bryant JP,Chapin FS,Klein DR.1983.Carbon/nutrient balance of boreal plants in relation to vertebrate herbivory.Oikos,40:357～368
[6] Cannell MGR,Dewar RC.1994.Carbon allocation in trees:A review of concepts for modeling.In:Begon M,Fitter AH,eds.Advances in Ecological Research.London:Academic Press.59～104
[7] Chapin FS Ⅲ.1980.The mineral nutrition of wild plants.Ann Rev Ecol Syst,11:233～260
[8] Chapin Ⅲ FS,Matson PA,Mooney HA.2002.Principles of Terrestrial Ecosystem Ecology.New York:Springer-Verlag.
[9] Cheng L,Fuchigami LH.2000.Rubisco activation state decreases with increasing nitrogen content in apple leaves.J Exp Bot,51:1687～1694
[10] Crawford NM,Glass DMA.1998.Molecular and physiological aspect of nitrate uptake in plants.Trends Plant Sci,3:389～395
[11] de Groot CC,Marcelis LFM,van den Boogaard R,et al.2001.Growth and dry-mass partitioning in tomato as affected by phosphorus nutrition and light.Plant Cell Environ,24:1309～1317
[12] Eckstein RL,Karlsson PS.2001.Variation in nitrogen-use efficiency among and within subarctic graminoids and herbs.New Phytol,150:641～651
[13] Evans JR.1989.Photosynthesis and nitrogen relationships in leaves of C3 plants.Oecologica,78:9～19
[14] Gower ST,Vogt KA,Grier CC.1992.Carbon dynamics of Rocky Mountain Douglas-fir:Influence of water and nutrient availability.Ecol Monogr,62:43～65
[15] Herms DA,Mattson WJ.1992.The dilemma of plants:To grow or defend.Q Rev Biol,67:283～335
[16] Horneck DA,Miller RO.1998.Determination of total nitrogen in plant tissue.In:Kalra YP,ed.Handbook of Reference Methods for Plant Analysis.New York:CRC Press.75～83
[17] Lambers H,Freijsen N,Poorter H,et al.1990.Analysis of growth based on net assimilation rate and nitrogen productivity their physiological background.In:Lambers H,Cambridge ML,Konings,Pons TL,eds.Causes and Consequences of Variation in Growth Rate and Productivity of Higher Plants.The Hague,The Netherlands:SPB Academic Publishing.1～18
[18] Masarovicova E.1997.Measurements of plant photosynthetic activity.In:Pessarakli M,ed.Handbook of Photosynthesis.New York:Marcel Dekker.769～801
[19] Mooney HA,Winner WE,Pell EJ.1991.Responses of Plants to Multiple Stresses.New York:Academic Press.
[20] Motomizu S,Wakimoto T,Toei K.1983.Spectra photometric determination of phosphate in river waters with molybdate blue and malachite green.Analyse,108:361～367
[21] Parry MAJ,Loveland JE,Andralojc PJ.1999.Regulation of rubisco.In:Bryant JA,Burrell MM,Kruger NJ,eds.Plant Carbohydrate Biochemistry.Oxford:BIOS Scientific Publishers.127～145
[22] Parsons R,Sunley RJ.2001.Nitrogen nutrition and the role of root-shoot nitrogen signaling particularly in symbiotic systems.J Exp Bot,52:435～443
[23] Poorter H,Nagel O.2000.The role of biomass allocation in the growth response of plants to different levels of light,CO₂,nutrients and water:A quantitative review.Aust J Plant Physiol,27:595～607
[24] Pregitzer KS,Dickmann DI,Hendrick R,et al.1990.Whole-tree carbon and nitrogen partitioning in young hybrid poplars.Tree Physiol,7:79～93