3.2 Shifting taxon composition at high hierarchy
Endophytic fungi showed shifting community composition among treatments
at high taxonomical hierarchy. Class Actinobacteria (mostly
Actinomycetales) followed by classes Alphaproteobacteria (mostly
Rhizobiales and Sphingomonadales) and Gammaproteobacteria (mostly
Xanthomonadales and Oceanospirillales) dominated the endophytic
bacterial communities in aerial tissues, roots, and the whole plant ofK . schrenkianum (Fig. 1a).
No bacterial class showed
significant difference in abundance with radiation level.
Dothideomycetes, Sordariomycetes, and unassigned fungi were the most
prevalent fungal groups. Dothideomycetes was the most abundant class in
the endophytic fungal communities associated with K. schrenkianum(Fig. 1b). Dothideomycetes significantly predominated the aerial tissues
regardless of the radiation level while it was the second most abundant
fungal class in the roots (Table S2). Order Pleosporales dominated
Dothideomycetes class. Unassigned fungi were the most abundant group in
the roots of plants from control, low, and medium radioactive
environments while Sordariomycetes (mostly Hypocreales, Microascales,
Sordariales, and Xylariales) was the predominant fungal class in the
roots of plants from high radioactive environment.
Among the endophytic fungi of K . schrenkianum roots, the
abundance of ascomycetous classes Leotiomycetes, Sordariomycetes, and
unassigned fungi significantly varied among the radiation levels (Table
S2). Meanwhile, among the endophytic fungi from aerial tissues, the
abundance of basidiomycetous class Agaricomycetes and unassigned fungi
significantly varied among the radiation levels. In the whole plant,
abundance of the members of classes Leotiomycetes, Sordariomycetes, and
Mortierellomycetes and that of the members of phyla Aphelidiomycota and
Rozellomycota significantly differed among the radiation levels.