Diversity and distribution patterns of root-associated fungi on herbaceous plants in alpine meadows of southwestern China

Abstract

The diversity of root-associated fungi associated with four ectomycorrhizal herbaceous species, Kobresia capillifolia, Carex parva, Polygonum macrophyllum and Potentilla fallens, collected in three sites of alpine meadows in southwestern China, was estimated based on internal transcribed spacer (ITS) rDNA sequence analysis of root tips. Three hundred seventy-seven fungal sequences sorted to 154 operational taxonomical units (sequence similarity of ≥ 97% across the ITS) were obtained from the four plant species across all three sites. Similar taxa (in GenBank with ≥ 97% similarity) were not found in GenBank and/or UNITE for most of the OTUs. Ectomycorrhiz a made up 64% of the fungi operational taxonomic units (OTUs), endophytes constituted 4% and the other 33% were unidentified root-associated fungi. Fungal OTUs were represented by 57% basidiomycetes and 43% ascomycetes. Inocybe, Tomentella/Thelophora, Sebacina, Hebeloma, Pezizomycotina, Cenococcum geophilum complex, Cortinarius, Lactarius and Helotiales were OTU-rich fungal lineages. Across the sites and host species the root-associated fungal communities generally exhibited low host and site specificity but high host and sampling site preference. Collectively our study revealed noteworthy diversity and endemism of root-associated fungi of alpine plants in this global biodiversity hotspot.

• alpine areas
• herbaceous plants
• ITS rDNA
• root-associated fungi

Acknowledgments

We thank Dr Bang Feng at the Kunming Institute of Botany, Chinese Academy of Sciences, and Dr Xiaofei Tian at the Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, for their kind help. Many thanks to the associate editor of Mycologia and the two anonymous reviewers for their comments that led to major improvements of our manuscript. This study was supported by joint funds from the National Natural Science Foundation of China and the Yunnan provincial government (No. U0836604) and by the National Basic Research Program of China (No. 2009CB522300).