氮肥和容器深度对栓皮栎容器苗生长、根系结构及养分贮存的影响  

Effects of Nitrogen Supply and Container Size on Seedling Growth,Root Characteristics,and Nutrient Status in Quercus variabilis Container Seedlings

作　　者：程中倩[1] 李国雷[1] 

机构地区：[1]北京林业大学省部共建森林培育与保护教育部重点实验室,城乡生态环境北京实验室,北京100083

出　　处：《林业科学》2016年第4期21-29,共9页Scientia Silvae Sinicae

基　　金：中央高校基本科研业务费专项(TD2011-08);北京市共建项目专项;"十二五"农村领域国家科技计划(2015BAD15B01)

摘　　要：【目的】氮肥施用量或容器深度可有效调控苗木质量,本研究同时采用2种措施培育容器苗,探讨2种措施对苗木质量提升的叠加效应,为丰富苗木质量调控措施提供参考。【方法】以1年生栓皮栎容器苗为试验材料,采用双因素完全随机试验设计,设置2个施肥水平(100 mg N·株^(-1))及2个容器深度(25,36 cm),通过测定第1年生长季末栓皮栎苗高、地径、生物量、养分浓度以及不同径级根系体积、表面积、长度。【结果】施氮肥与容器长度交互效应对根氮浓度和中等径级根系(2~3 mm)的根体积、表面积显著,25 mg N-36 cm组合有利于中等根系径级生长,100 mg N-36 cm组合有利于根系氮浓度提高,这表明交互效应对地下部分的影响大于地上,2种措施交互作用通过影响根系来调控苗木质量。主效应表明,充足施肥量有利于地径生长、根氮和钾浓度提高;容器长度对根系结构的影响较施氮量显著,深容器可促进根系径级为3~4 mm的根系发育,否则造成窝根;长容器可促进苗高生长、茎生物量积累以及茎氮浓度提高。【结论】苗木生长、养分、根系结构对施氮量与容器深度的交互效应与主效应响应规律证实2种措施相结合调控苗木质量的必要性。主根发达树种栓皮栎容器苗最佳组合为100 mg N和36 cm深的容器。【Objective】Nitrogen（ N） supply and container type have each proved to effectively regulate seedling quality.In this study, we tested if the combination of the two approaches couldimprove seedling quality and produce a superposition effect on seedling growthin order to provide a theoretical basis in the containerized seedling cultivation.【Method】Quercus variabilis,with a dominant taproot,was reared in two different depth containers（ 25 cm,36 cm） with application of either deficient（ 25 mg N·seedling^（-1）） or luxury（ 100 mg N·seedling^（-1）） nitrogen supply,in a two factors completely randomize design. Seedling growth,root characteristics,and nutrient concentration were measured at the end of the growth season. 【Result】N supply and container depth were significantly interacted on root N concentration,root volume,andsurface area for medium- class roots（ 2. 0 D≤3. 0 mm）,indicating that interactive effects of N supply and container depth were associated with underground rather than aboveground attributes. The combination of 25 mg N-36 cm container promoted root development with medium root classes while the combination of 100 mg N-36 cm container improved root N concentration. For the main effects,high N supply favored RCD,N and K concentration in roots.Container depth yielded more profound effects on root characteristics compared to N supply. Deep container facilitated root growth with root diameter between 3 and 4 mm whereas shallow one led to root spiraling. Additionally deep container increased seedling height,stem dry mass and N concentration. 【Conclusion】Both the interactive and main effects of N supply and container depth indicated the necessity of combining the two approaches to improve seedling quality. Theoptimum combination of 100 mg N and 36 cm container was recommended for the container seedling production of this species with a dominant taproot.

关 键 词：容器苗 氮肥 容器深度 根系结构 苗木生长 养分浓度 

分 类 号：S718.43[农业科学—林学]