Objective  Community diversity and structures of the bacteria in the rhizosphere and endosphere of wild Cymbidium ensifolium were studied to understand the symbiotic relationship between them.

  Method  The high-throughput sequencing method was applied to identify the bacteria in the rhizosphere soil and the root-endosphere of C. ensifolium at locations in Mt. Gushan, Fuzhou where the wild orchids were found. Species diversity and community structures of the spheres were compared.

  Result  Numerous species of bacteria were found in the specimens. The Simpson index in the rhizosphere soil was determined to be of 0.99, and that in the root-endosphere 0.95. The Shannon indices indicated that the rhizosphere was significantly more diverse on species than the root-endosphere. There were 10 phyla of bacteria in the rhizosphere with the dominant ones being Proteobacteria (60.5%), Acidobacteria (20.5%), and Actinobacteria (15.3%). In the root-endosphere, the prevailing phyla were Proteobacteria (75.3%), Acidobacteria (7.3%), and Actinobacteria (14.6%). Among the 10 bacterial genera in the highest abundance, Solibacter and Acidipila existed only in the rhizosphere, while Dyella, Novosphingobium, and Granulicella only in the root-endosphere. The abundance of Acidobacteria Acidobacteriia bacteria in the rhizosphere were significantly higher than those in the root-endosphere. Of the 11 significantly different orders, only Enterobacteriales showed a greater abundance in the root-endosphere than in the rhizosphere. There were 12 genera significantly more abundant in the rhizosphere than in the root-endosphere.

  Conclusion  The significantly different microbial community diversity and structures in the field rhizosphere and root-endosphere of wild C. ensifolium grown at the same area might reflect a highly complex synergism between the environment and the plants.