Timonen Sari, Sinkko Hanna, Sun Hui, Sietiö Outi-Maaria, Rinta-Kanto Johanna M, Kiheri Heikki, Heinonsalo Jussi
Department of Food and Environmental Sciences, Division of Microbiology and Biotechnology, University of Helsinki, P.O. Box 56, 00014, Helsinki, FIN, Finland.
Collaborative Innovation Center of Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, China.
Microb Ecol. 2017 May;73(4):939-953. doi: 10.1007/s00248-016-0922-6. Epub 2016 Dec 26.
In this study, the bacterial populations of roots and mycospheres of the boreal pine forest ericoid plants, heather (Calluna vulgaris), bilberry (Vaccinium myrtillus), and lingonberry (Vaccinium vitis-idaea), were studied by qPCR and next-generation sequencing (NGS). All bacterial communities of mycosphere soils differed from soils uncolonized by mycorrhizal mycelia. Colonization by mycorrhizal hyphae increased the total number of bacterial 16S ribosomal DNA (rDNA) gene copies in the humus but decreased the number of different bacterial operational taxonomic units (OTUs). Nevertheless, ericoid roots and mycospheres supported numerous OTUs not present in uncolonized humus. Bacterial communities in bilberry mycospheres were surprisingly similar to those in pine mycospheres but not to bacterial communities in heather and lingonberry mycospheres. In contrast, bacterial communities of ericoid roots were more similar to each other than to those of pine roots. In all sample types, the relative abundances of bacterial sequences belonging to Alphaproteobacteria and Acidobacteria were higher than the sequences belonging to other classes. Soil samples contained more Actinobacteria, Deltaproteobacteria, Opitutae, and Planctomycetia, whereas Armatimonadia, Betaproteobacteria, Gammaproteobacteria, and Sphingobacteriia were more common to roots. All mycosphere soils and roots harbored bacteria unique to that particular habitat. Our study suggests that the habitation by ericoid plants increases the overall bacterial diversity of boreal forest soils.
在本研究中，通过定量聚合酶链反应（qPCR）和下一代测序（NGS）对北方松树林石南科植物、石南（帚石楠）、越橘（笃斯越橘）和红果越橘的根及菌根圈的细菌群落进行了研究。所有菌根圈土壤的细菌群落都与未被菌根菌丝定殖的土壤不同。菌根菌丝的定殖增加了腐殖质中细菌16S核糖体DNA（rDNA）基因拷贝的总数，但减少了不同细菌操作分类单元（OTU）的数量。然而，石南科植物的根和菌根圈支持了许多未定殖腐殖质中不存在的OTU。越橘菌根圈中的细菌群落与松树菌根圈中的细菌群落惊人地相似，但与石南和红果越橘菌根圈中的细菌群落不同。相比之下，石南科植物根的细菌群落彼此之间比与松树根的细菌群落更相似。在所有样本类型中，属于α-变形菌纲和酸杆菌纲的细菌序列的相对丰度高于属于其他类别的序列。土壤样本中含有更多的放线菌、δ-变形菌纲、疣微菌门和浮霉菌门，而芽单胞菌门、β-变形菌纲、γ-变形菌纲和鞘脂杆菌纲在根中更为常见。所有菌根圈土壤和根都含有该特定栖息地特有的细菌。我们的研究表明，石南科植物的栖息增加了北方森林土壤的整体细菌多样性。
