Structure and Co-occurrence Network Characteristics of Rhizosphere Soil Fungal Communities of Alsophila spinulosa in Subtropical Chishui River Valley, China

Abstract

Aims The co-occurrence of soil microorganisms and plants is of great significance in revealing the material cycle. The study of the community structure and co-occurrence network relationship of rhizosphere soil fungi of the relict plant Alsophila spinulosa can reveal the mechanism of constructing soil fungal communities. Methods The community structure and co-occurrence network characteristics of soil fungi in the rhizosphere of A. spinulosa were analysed using Illumina Miseq sequencing technology and co-occurrence networks. Results The rhizosphere soil fungal communities of A. spinulosa are significantly different from those in the nonrhizosphere soil. The rhizosphere soil fungal phylogeny of A. spinulosa was concentrated in Ascomycota, Mortierellomycota, and Rozellomycota. Aggregation of Cutaneotrichosporon, the main differential species, significantly affected the construction of the rhizosphere fungal community of A. spinulosa. The indicator fungal groups of the rhizosphere soil fungal community of A. spinulosa were significantly influenced by habitat. Saprotrophs are the main fungi responsible for material exchange in A. spinulosa. Increase in the relative abundance of animal pathogens was the main factor affecting the percentage of pathotroph. The rhizosphere soil fungal co-occurrence networks of A. spinulosa had high synergism and network connectivity, and more intense interspecies competition at the order level. Conclusions Overall, the rhizosphere soil fungal community of A. spinulosa altered significantly, with a stable co-occurrence network. Continuous in-depth study on the growth of the key soil fungi can help understand the growth mechanism of A. spinulosa.