Fig. 4: Nitrogen response of positively AMF-associated bacterial genes enriched functions leading by ABC transport and amino acid metabolism.

a The 34 microbial KOs that are significantly higher in N50 (n = 5) than N0 (n = 4) enriched functions, including ABC transporters, histidine metabolism, valine leucine and isoleucine biosynthesis, base excision repair, mismatch repair, pentose phosphate pathway, and nucleotide metabolism. Note that we focused exclusively on the N50 level because we did not identify a sufficient number of differentially expressed genes for functional enrichment analysis in other nitrogen addition levels (Supplementary Fig. S11). b A heatmap illustrates the association between microbial genes underpinning these enriched functions and environmental variables. It highlights positive correlations with nitrogen addition level and soil available phosphorus, and negative correlations with soil pH and plant richness. c A bar plot demonstrates that there is a significant difference in the richness of AMF-associated bacteria between N50 (n = 5) and N0 (n = 4). d A stacked bar plot illustrates that in N50 (n = 5), the abundance of AMF-associated Actinobacteria was significantly higher compared to N0 (n = 4).