基于高通量测序的闽楠幼林根际土壤丛枝菌根真菌群落变化

Variation of arbuscular mycorrhiza fungal communities in the rhizosphere soil of Phoebe bournei (Hemsl.) Yang plantations based on high-throughput sequencing analysis

摘要:

【背景】闽楠是珍贵用材树种。阐明闽楠根际土壤微生物特征，对科学经营闽楠人工林有指导作用。【目的】明确闽楠人工林恢复过程中根际土壤丛枝菌根群落随林龄的变化特征。【方法】采用高通量Illumina Miseq测序的方法，评估不同林龄闽楠幼林根际土壤丛枝菌根真菌(Arbuscular Mycorrhiza Fungi，AMF)群落的多样性和组成，揭示造林后闽楠根际土壤真菌群落对时间序列中土壤养分变化的响应特征。【结果】从3个林龄闽楠根际土壤中共得到342 555条有效序列，共得到253个AMF-OTU，分属于1门1纲5目9科14属。α多样性指数表明，丛枝菌根真菌群落的Chao1、Shannon指数随着林龄的增加而增加，但不同林龄间差异不显著。β多样性指数表明，在闽楠幼龄阶段，不同林龄间AMF群落组成差异明显。根据Bray-Curtis相异度分析阐明AMF群落组成的相似性与林龄相关。种水平物种丰度与土壤因子的相关性分析表明，影响AMF群落丰度的主要土壤因子是pH、全钾、硝态氮和铵态氮。铵态氮与优势AMF分子虚拟种Glomus-Franke-A1-VTX00076、Glomus-Franke-A1-VTX00269的丰度呈显著正相关。【结论】随着林龄的增加，闽楠幼龄根际土壤丛枝菌根真菌的种类组成发生了显著变化，影响AMF特性的主要土壤因子是pH、全钾、硝态氮和铵态氮。这些发现将有助于揭示闽楠幼林生态系统和土壤微生物多样性的相互关系和机制，为生物多样性-生态系统功能实验提供理论依据。

Abstract:

[Background] Phoebe bournei (Hemsl.) Yang is a precious timber species. Clarifying the characteristics of rhizosphere soil microorganism of P. bournei is helpful for scientific management of P. bournei plantations. [Objective] To understand the changes of arbuscular mycorrhiza community in rhizosphere soil of P. bournei (Hemsl.) Yang plantation with forest age after the afforestation. [Methods] The diversity and composition of arbuscular mycorrhiza fungal communities in the rhizosphere soil of P. bournei plantations at different ages were evaluated by high-throughput Illumina Miseq sequencing. Then, we analyzed response characteristics of soil fugal communities in the rhizosphere soil of P. bournei plantations to changing soil nutrient after afforestation. [Results] In total, 342 555 effective sequences and 253 AMF-OTUs were obtained from the rhizosphere soils of 3 forest ages of P. bournei, belonging to 14 genus, 9 families, 5 orders, 1 class, 1 phylum. In terms of alpha diversities, both Chao1 and Shannon indices of AMF community increased with the plantation age of P. bournei, but there was no significant difference among different plantation ages. There was significant difference of β diversity in arbuscular mycorrhiza fungal community composition among different plantation ages. According to the Bray-Curtis dissimilarity analysis, the similarity of AMF community composition was related to plantation ages. The Spearman correlation analysis between species richness and soil factors indicated that the majority soil factors affecting the abundance of arbuscular mycorrhiza fungal communities were pH, total potassium (K), nitrate nitrogen (NO3–-N) and ammonium nitrogen (NH4+-N). Ammonium was significantly correlated with the abundance of dominant arbuscular mycorrhiza fungal molecular virtual species Glomus-Franke-A1-VTX00076 and Glomus-Franke-A1-VTX00269. [Conclusion] Our findings reveal the relationship between soil microbial diversity and the ecosystem of Phoebe bournei (Hemsl.) Yang plantations and provide reference for understanding the relationships between biodiversity and ecosystem functions.