Study on the Soil Microbial Diversity of Cymbidium goeringii and Cymbidium faberi in the Qinling Mountains after Introduction and Domestication

Abstract

Rhizosphere microbial communities have abundant species and a large number, and affect the physiology and growth of plants. When studying rhizosphere microbes, the rhizosphere ecosystem function and protection of wild orchids will be facilitated. By using high-throughput sequencing technology, the rhizosphere and non-rhizosphere bacteria and fungi of wild Cymbidium goeringii and Cymbidium faberi in the Qinling Mountains were analyzed at phylum, class, order, family, and genus levels to explore the rhizosphere bacterial and fungal community structure and diversity of orchid plants (C. goeringii and C. faberi) under natural conditions. The results showed that at the phylum level Proteobacteria was dominant in rhizosphere and non-rhizosphere soil of C. goeringii and C. faberi, but the proportion was different. The abundance of Proteobacteria in rhizosphere soil of C. faberi was the highest (35.5%), which was about 1.3 times of that in non-rhizosphere soil. Bacteroidetes accounted for 17.2% in rhizosphere soil of C. goeringii, much higher than that of non-rhizosphere soil (7.92%). The dominant groups of fungi in rhizosphere soil of C. goeringii and C. faberi were both Ascomycota. At the genus level, PCoA analysis showed that the community structure of bacteria and fungi in different samples was not only common but also specific, which was manifested in the similar dominant species but different subdominant species. This difference is reflected in the composition and relative abundance of microbial communities between different samples, and will gradually become obvious with the refinement of genera.