罗甸小米核桃幼苗对光照强度变化的生理响应  

Eco-physiological Responses of Juglans regia Seedling to Different Light Intensity

作　　者：刘济明[1] 闫国华[1] 徐国瑞[2] 王敏[1] 张东凯[1] 廖小锋[1] 

机构地区：[1]贵州大学林学院,贵州贵阳550025 [2]中国科学院生态环境研究中心,北京100085

出　　处：《西南农业学报》2012年第6期2059-2064,共6页Southwest China Journal of Agricultural Sciences

基　　金：贵州省林业厅重大课题"喀斯特地区特色经济林树种培育与示范"[黔林科合重大(2010)04]

摘　　要：为了探明罗甸小米核桃幼苗与光生境的关系,为罗甸小米核桃栽培管理提供科学依据,以罗甸小米核桃(Juglans regia L. f. luodianense Liu et Xu)一年生幼苗为试验材料,研究了不同光照强度对盆栽罗甸小米核桃生理生态的影响。结果表明:①随着光照强度的减少,地径增粗减少,全光照下的地径净增量最大,而中度遮阴环境下,罗甸小米核桃幼苗苗高净增量高于其他处理,且幼苗获得最大的苗高生长能力;②随着光照强度的减小,逐渐加大对复叶的资源投入,降低茎干方面的投入,根冠比增大,中度遮阴可使幼苗获得最大产量;③随着光照强度的减小,气孔导度和净光合速率呈现先升后降的趋势,并在轻度和中度遮阴环境下达到较高水平;④遮光条件下,罗甸小米核桃一年生幼苗的chla、chlb和chl(a+b)相对于全光照(CK)的差异显著,chl a/b在重度遮阴下显著降低。说明,适度的遮阴可能有利于罗甸小米核桃幼苗的生长。To reveal the relationship between light environments and 1-year J. reg/a seedling, the investigation on eco-physiological responses of 1-year J. reg/a seedling to different light intensity was done. The result showed that： （i） The stem diameter decreased, and the net increment of stem diameter reached the maximum under full sunlight. Moreover, J. regia got maximum height growth ability under moderate shading; （ii） In biomass, with the degree of shading reduction the plant gradually increased investment of resources on fronds and decreased investment of resources on stems, the root biomass/shoot biomass ratio increased at the same time. The biomass per plant reached the maximum under moderate shading; （iii） With the degree of shading reduction, the net photosynthetic rate （Pn） and stomatal conductance （cond） first increased and then decreased, besides, the net photosynthetic rate（Pn） and stomatal conductance （cond） leaves increased to maximal levels under moderate shading and light shading; （iv） Under shading, the leaf chlorophyll a, chlorophyll b and total chlorophyll contents of J. reg/a had significant differences to those in full sunlight, and the chlorophyll a/b ratio under severe shading decreased significandy. In general, moderate shading might be beneficial in 1-year J. regia seedling growth.

关 键 词：光照强度 小米核桃 生理生态响应 一年生幼苗 罗甸 

分 类 号：S664.104.7[农业科学—果树学] Q945.7[农业科学—园艺学]