Fig. 6

Bar graph of the species difference test. A: between the root and rhizosphere soil groups at the 16S OTU level; B: between the endangered and widespread species groups at the ITS OTU level. The positive and negative difference in mean relative abundance represents the abundance of OTUs in the corresponding group. *P ≤ 0.05. **0.01 ≤ P ≤ 0.05. ***0.001 ≤ P ≤ 0.01. ITS, internal transcribed spacer; OTU, operational taxonomic unit