Da Cheng Hao, Si Meng Song, Wen Li Hu, Jun Mu and Pei Gen Xiao
Biotechnology Institute, School of Environment and Chemical Engineering, Dalian Jiaotong University, Dalian 116028, China
The species variability and potential environmental functions of Taxus rhizosphere microbial community were studied by comparative analysis of 15 16S rRNA and 15 ITS MiSeq sequencing libraries from the Taxus rhizosphere in subtropical and temperate regions of China, as well as by isolating laccase-producing strains and polycyclic aromatic hydrocarbon (PAH)-degrading strains. Total reads could be assigned to 2,141 Operational Taxonomic Units (OTUs) belonging to 31 bacteria phyla and 2,904 OTUs of at least seven fungi phyla. The abundance of Planctomycetes, Actinobacteria, and Chloroflexi was higher in rhizospheres of the temperate region (MD and ZS) than in the subtropical T. mairei rhizosphere (NF), while Acidobacteria, Proteobacteria, Nitrospirae, and unclassified bacteria were more abundant in the latter. Ascomycota and Zygomycota were predominant in NF, while MD and ZS had more unclassified fungi, Basidiomycota, and Chytridiomycota. The bacterial/fungal community richness and diversity were lower in NF than in MD and ZS. Three laccase-producing fungal isolates were shown to be highly efficient in dye discoloration, while two PAH-degrading fungi were able to degrade recalcitrant benzopyrene. The present studies extend the knowledge pedigree of the microbial diversity populating rhizospheres, and exemplify the paradigm shift in research and development of resource plant rhizosphere.