施N对蚬木苗期镉胁迫下干物质及N、P、K和Cd积累和分配的影响  

Effects of N on Accumulations and Distributions of Dry Matters and N,P,K and Cd in Excentrodendron hsienmu Seedlings under Cd Stress

作　　者：韦宇 谭长强[2] 申文辉[2] 彭健 韦长江 滕维超[1] Wei Yu;Tan Zhangqiang;Shen Wenhui;Peng Jian;Wei Changjiang;Teng Weichao(College of Forestry,Guangxi University,Nanning,Guangxi 530004,China;Guangxi Forestry Research Institute,Nanning,Guangxi 530002,China;Guangxi Key Laboratory of Forest Ecology and Conservation,College of Forestry,Guangxi University,Nanning,Guangxi 530004,China;Key Laboratory of National Forestry and Grassland Administration on Cultivation of Fast-Growing Timber in Central South China,College of Forestry,Guangxi University,Nanning,Guangxi 530004,China;Guangxi Colleges and Universities Key Laboratory for Forestry Science and Engineering,College of Forestry,Guangxi University,Nanning,Guangxi 530004,China;Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources,College of Forestry,Guangxi University,Nanning,Guangxi 530004,China;Guangxi State-owned Sanmenjiang Forest Farm,Liuzhou,Guangxi 545006,China)

机构地区：[1]广西大学林学院,广西南宁530004 [2]广西壮族自治区林业科学研究院,广西南宁530002 [3]广西大学林学院广西森林生态与保育重点实验室,广西南宁530004 [4]广西大学林学院中南速生材繁育国家林业和草原局重点实验室,广西南宁530004 [5]广西大学林学院广西高等学校林业科学与工程重点实验室,广西南宁530004 [6]广西大学林学院亚热带农业生物资源保护与利用国家重点实验室,广西南宁530004 [7]广西壮族自治区国有三门江林场,广西柳州545006

出　　处：《广西林业科学》2022年第6期809-816,共8页Guangxi Forestry Science

基　　金：广西科技计划项目(桂科AB16380300);广西林业科技推广项目(gl2019kt13)。

摘　　要：为了解蚬木(Excentrodendron hsienmu)对镉(Cd)胁迫环境的适应性及施氮(N)对该树种对Cd的解毒机制,为土壤Cd污染的治理提供参考,采用盆栽方法,研究不同Cd、N处理对蚬木干重及N、磷(P)、钾(K)和Cd积累和分配的影响。结果表明,Cd胁迫抑制蚬木根、茎、叶和总干重增加,N、P和K的吸收和积累受到限制。蚬木通过提高N、P和K利用率,增加根冠比,更好地适应Cd胁迫环境。Cd胁迫后,根系中Cd含量和积累量增加,增加程度大于茎和叶。随Cd浓度增加,蚬木Cd转移系数逐渐下降。在30 mg/kgCd胁迫下,随施N浓度增加,茎、叶和总干重增加,根干重先增后减;低N(0.4 g/kg)提高根干重分配比例与根冠比,高N(0.8 g/kg)提高茎、叶干重分配比例。施N提高根、茎和叶N、K含量和积累量及总积累量;随施N浓度增加,叶和总N/P值均升高,根和茎N/P值及P利用率均先升后降,茎、叶和总P/K值降低,根P/K值先降后升,说明施N促进N和K吸收,限制P吸收;随施N浓度增加,地上部分富集系数逐渐降低,Cd在地上部分的分配比例逐渐降低,地下部分富集系数先降后升,Cd在根的分配比例逐渐升高,说明施N处理提升蚬木耐Cd性。In order to understand adaptability of Excentrodendron hsienmu to Cd stress and detoxification mech⁃anism of this tree species with N application and provide reference for treatment of soil Cd pollution,effects of different Cd and N treatments on dry matter weights and accumulations and distributions of N,P,K and Cd of E.hsienmu were studied by pot culture.Results showed that Cd stress inhibited increase of root,stem,leaf and total dry matter weights of E.hsienmu,and absorption and accumulations of N,P and K were limited.E.hsien⁃mu could better adapt to Cd stress by increasing use efficiencies of N,P and K and root to shoot ratio.After Cd stress,content and accumulation of Cd in root increased,and increase degree was significantly greater than those in stem and leaf.Transfer coefficient of Cd of E.hsienmu decreased gradually with increase of Cd concen⁃tration.Under 30 mg/kg Cd stress,dry matter weights in stem,leaf and total increased with increase of N con⁃centration,while dry matter weight in root increased firstly and then decreased.Low N(0.4 g/kg)increased dis⁃tribution ratio of dry matter weight in root and root to shoot ratio,and high N(0.8 g/kg)increased distribution ra⁃tios of dry matter weights in stem and leaf.Application of N could promote contents and accumulations of N and K in root,stem,leaf and total.With increase of N concentration,N/P values of leaf and total increased,N/P val⁃ues of root and stem as well as P use efficiency increased firstly and then decreased,P/K values of stem and leaf and total decreased,and P/K value of root decreased firstly and then increased,which indicated application of N promoted absorption of N and K,and limited P absorption.With increase of N concentration,enrichment coef⁃ficient of aboveground part gradually decreased,distribution ratio of Cd in aboveground part gradually de⁃creased,enrichment coefficient of underground part firstly decreased and then increased,and distribution ratio of Cd in root gradually increased,which indicated that applicatio

关 键 词：CD胁迫 氮肥 蚬木 干物质 营养元素 

分 类 号：S792[农业科学—林木遗传育种]