To study the effect of biochar addition on the community structure and interaction of rhizosphere fungi in manure-fertilized soil, a pot experiment with ryegrass (Lolium perenne L.) was performed to assess community succession and the molecular ecological network of rhizosphere fungi with the addition of 2% (w/w) biochar and manure-only treatments. The results of Illumina MiSeq sequencing indicated that there was no significant difference between the soil fungal α-diversity (Shannon index) of the control group and that of the biochar group. Ascomycota, Basidiomycota, and Zygomycota were the dominant fungal phyla across all samples with relative abundances ranging from 59.64% to 84.80%, 1.90% to 5.87%, and 4.34% to 16.11%, respectively. Molecular ecological network analysis indicated that fungal communities in the biochar treatment had more complex associations and significantly enhanced positive correlations compared to those of the control group (P<0.05). Mantel test analysis indicated that plant root was significantly correlated with fungal abundance and community interactions in the biochar treatment (P=0.001). Plant root was the most important factor in altering fungal abundance and interactions.
Keywords: biochar; manure; network analysis; rhizosphere fungi; ryegrass.