New insights into the composition and diversity of endophytic bacteria in cultivated Huperzia serrata

Endophytic bacteria play crucial roles in the growth and bioactive compound synthesis of host plants. In this study, the composition and diversity of endophytic bacteria in the roots, stems, and leaves from 3-year-old artificially cultivated Huperzia serrata were investigated using Illumina HiSeq sequencing technology. Total effective reads were assigned to 936 operational taxonomic units (OTUs), belonging to 12 phyla and 289 genera. A total of 28, 3, and 2 OTUs were exclusive to the roots, stems, and leaves, respectively. The bacterial richness and diversity in the roots were significantly lower than those in the leaves and stems. The dominant genera with significant distribution differences among these plant tissue samples were Burkholderia-Caballeronia-Paraburkholderia, Sphingomonas, Acidibacter, Bradyrhizobium, Bryobacter, Methylocella, Nocardioides, Acidothermus, and Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium. Furthermore, the differences in the bacterial communities associated with these plant tissue samples were visualized using principal coordinate analysis and cluster pedigree diagrams. Linear discriminant analysis effect size explained statistically significant differences among the endophytic bacterial microbiota in these plant tissue samples. Overall, this study provides new insights into the diversity and distribution patterns of endophytic bacteria in the different tissues of H. serrata.