[目的]通过分析种植方式对两种菌根类型树种吸收根性状的影响,揭示物种共存的适应条件.[方法]本研究选择8个树种(5个AM树种和3个EM树种)的单种和所有树种混种的样地,分析不同种植方式(单种vs混种)下两类型菌根(AM vs EM)树种吸收根(1～2级根)的主要形态性状(根直径、比根长、根组织密度、单根长)和构型性状(根分支强度、根分支比)及菌根侵染率的差异.[结果]菌根类型极显著影响吸收根的形态和构型性状(p<0.001),显著影响菌根侵染率(p<0.05);种植方式仅显著影响吸收根的组织密度和根构型性状(p<0.05);菌根类型和种植方式对所有性状均无交互影响(p>0.05).AM树种根性状间的相关程度高于EM树种,混种大幅度降低AM树种根性状间的相关性.混种降低AM树种根形态性状的可塑性(比根长除外),增大其构型性状的可塑性;混种降低EM树种根组织密度的可塑性,增大根直径、构型性状及侵染率的可塑性.[结论]AM和EM树种的根形态和构型性状均有显著差异.混种对AM和EM树种根性状的可塑性有不同程度的影响,主要增大AM树种的分支强度,降低EM树种的根组织密度.可见,不同菌根树种可以通过调节不同根性状变化来实现物种共存.
The Influence of Planting Patterns and Mycorrhizal Types on Absorptive Root Traits
[Objective]The effects of planting methods and the mycorrhizal types on absorptive root traits of tree species were analyzed to reveal the adaptive conditions for species coexistence.[Methods]In this study,monoculture and mixture of 8 species(5 AM and 3 EM)were selected.The main morphological traits(root diameter,specific root length,root tissue density,individual root length)and architectural traits(root branching intensity,root branching ratio strength)and mycorrhizal colonization of absorptive roots(first two order roots)of two types of mycorrhizal tree species(AM vs EM)under two planting patterns(monoculture vs mixture)were analyzed.[Results]Mycorrhiza significantly affected morphological and ar-chitectural traits of absorptive roots(p<0.001),and significantly affected mycorrhizal colonization(p<0.05);while planting patterns only significantly affected root tissue density and root architectural traits(p<0.05);mycorrhizal types and planting patterns had no interaction on all root traits(p>0.05).The correlation between root traits of AM species was higher than that of EM species,and the mixture greatly reduced cor-relations between root traits of AM tree species.For AM species,the mixture reduced the plasticity of root morphological traits(except for specific root length)and increased the plasticity of architectural traits.For EM species,the mixture reduced the plasticity of root tissue density,and increased the plasticity of root diameter,architectural traits and mycorrhizal colonization.[Conclusion]There are significant differences in root morphological and architectural traits between AM and EM species.Mixed forests mode has varying degrees of effects on the plasticity of root traits of AM and EM species,mainly increasing the branching in-tensity of AM species and decreasing the root tissue density of EM species.Therefore,different mycorrhiz-al species can achieve species coexistence by regulating different root trait changes.
tree speciesarbuscular mycorrhizaectomycorrhizaroot traitsmycorrhiza colonization
万方数据
维普
