Analysis of fungal communities in roots and root-associated soil of Nervilia fordii from karst areas of Guangxi

Abstract

To explore the fungal community diversity in the roots of Nervilia fordii as well as in the root-associated soil, we collected the terrestrial orchids grown in Daxin (DX) County and Longzhou (LZ) County of the karst areas in Guangxi Zhuang Autonomous Region, China as well as the root-associated soil, respectively. We analyzed the composition of fungal communities in the roots and the root-associated soil by taking the Illumina MiSeq high-throughput sequencing technology. The results were as follows: (1)The fungal diversity in the roots and root-associated soil of DX and LZ were very rich. In addition, the diversity of fungi in root-associated soil was higher than that in roots, and the fungal diversity in the taproot was higher than that in walking stem. (2) A total of 118 040 valid sequences and 207 operational taxonomic unites (OTUs) were obtained. The BLAST results showed that these OUTs involved 8 phyla, 19 classes, 42 orders, 86 families and 123 genera. (3) The dominant fungal communities in roots of two areas (DX and LZ) both were Basidiomycota including Tulasnellaceae, Trimorphomycetaceae, Ceratobasidiaceae and Malasseziaceae as well as Marasmiaceae. Among them, Tulasnellaceae (75%) and Epulorhiza (Sexual type: Tulasnella) (56%) were the dominant family and genus, respectively. However, Fusarium was the dominant fungal genus in the root-associated soil. In conclusion, there is a significant difference in fungal communities between roots and root-associated soil, but there is some common OTUs. More importantly, our results also suggest that these fungi species belonging to Epulorhiza may play an important effect on the seed germination and seedling growth of Nervilia fordii grown in the karst area of Guangxi.

Keywords

• nervilia fordii
• mycorrhizal fungi
• high-throughput sequencing
• fungal diversity
• funguild