Abstract:

Aims Orchid plants generally grow better when they are mycorrhizal since mycorrhizal fungi are likely to assist in orchid seeds’ germination. However, there is little quantitative work on it. Thus we hope to better understand this mechanism to benefit the orchid plants protection.
Methods We studied nine small population species of orchids grown in Liaoning Province, China. We analyzed the composition of orchid mycorrhizal fungi (OMF) and fungal communities in the roots, in the rhizosphere soil as well as bulk soil, by taking advantage of the next generation sequencing technology.
Important findings Our study showed that there was a significant difference in fungal communities among in the roots, the rhizosphere soil and the bulk soil, especially in the total operational taxonomic unit (OTU) number. Although the OTU number was far smaller in the roots than in the rhizosphere soil and bulk soil, the species and abundances of OMF were less relative to each other. FunGuild, an indicator to predict the functional fungi, indicated that Arbuscular Mycorrhizal fungi were abundence in the rhizosphere while were rare in the roots of orchids. In general, the fungal communities in the roots were not tightly correlated with that in the root-associated soil.

Key words: orchids, mycorrhizal fungi, soil, internal transcribed spacer (ITS), high-throughput sequencing