Fig. 2 Phylogeny and LEfSe discrimination
Indicator taxa
The fungal community indicator taxa of nonrhizosphere and rhizosphere
soils of A. spinulosa were significantly different at different
taxonomic levels, with a large proportion of indicator taxa being
unclassified soil fungi (Table 1). At the phylum level, 12 rhizosphere
indicator taxa with IndVal values of 0.24–0.57 were observed, with the
obvious indicator taxon being Chytridiomycota (IndVal = 56.67%). Twelve
nonrhizosphere indicator taxa with IndVal values of 0.25–0.53 were also
observed at the phylum level, with the obvious indicator taxon being
Glomeromycota (IndVal = 52.71%). Only one indicator
taxon—Basidiomycota—was common between inter- and nonrhizosphere
soils.
At the order level, 84 rhizosphere indicator taxa with IndVal values of
0.21–0.63 were observed, with the obvious indicator taxon being
Chantharellales (IndVal = 63.40%). In total, 79 nonrhizosphere
indicator taxa with IndVal values of 0.21–0.67 were observed, with the
obvious indicator taxon being Orbiliales (IndVal = 67.43%).
At the family level, 154 rhizosphere indicator taxa with IndVal values
of 0.21–0.66 were observed, with the obvious indicator taxon being
Ceratobasidiaceae (IndVal = 66.43%). Further, 156 nonrhizosphere
indicator taxa with IndVal values of 0.20–0.68 were noted, with the
obvious indicator taxon being Cordycipitaceae (IndVal = 67.61%).
At the genera level, 241 rhizosphere indicator taxa with IndVal values
of 0.20–0.67 were observed, with the obvious indicator taxon being the
genus Tolypocladium (IndVal = 59.83%). In total, 250
nonrhizosphere indicator taxa with IndVal values of 0.20–0.69 were
observed, with the obvious indicator taxon being the genusAgaricus (IndVal = 69.12%).
At the species level, 241 rhizosphere indicator taxa with IndVal values
of 0.20–0.87 were observed, with the obvious indicator taxa being
unclassified species of the genera Ciliolarina andSerendipita ; both genera had an IndVal value of 86.96%. In
total, 283 nonrhizosphere indicator taxa with IndVal values of
0.20–0.91 were observed, with the obvious indicator taxa beingSaitozyma ninhbinhensis and Virgatospora echinofibrosa ;
both had an IndVal value of 91.30%.
The number of habitat-indicating taxa in the soil fungal community ofA. spinulosa was lower at three taxonomic levels, namely, order,
family, and genus, than at the nonrhizosphere level. The characteristic
indicator taxa were represented only at the species level, with 3
species of soil fungi being characteristic of the A. spinulosarhizosphere and 24 species of soil fungi being characteristic of the
nonrhizosphere.
The difference in indicator taxa indicates that soil fungal communities
have obvious indicator effects on A. spinulosa roots. The
unclassified taxa with indicator effects
on the A. spinulosarhizosphere soil may be crucial taxa reflecting the soil environmental
changes. However, this finding needs to be explored in future research.
Table 1 Indicative values for soil fungal taxa of A. spinulosa at
different taxonomic levels