Hg contamination in soil is an increasing global concern. Rhizosphere technology to remediate Hg pollution is direction of future work. Brassica juncea had been widely used for Hg contaminated soil remediation. However, the effects of Hg pollution to rhizobacteria of B. juncea has rarely reported. 16S rRNA amplicon sequencing was performed to assess the adaptation of rhizobacteria of B. juncea planted Hg contaminated soils under controlled conditions. The results showed that α-diversity and phylogenetic diversity of rhizobacteria increased with elevated Hg, within which SOC, TN, TP, TK, and C/N ratio were important in this process. β-diversity of rhizosphere microbiome vary along the Hg gradient, in which VWC, TN, TK, SOC, and THg played vital roles. The dominant phyla are composed of Proteobacteria, Actinobacteriota, Chloroflexi, Firmicutes, Bacteroidota, Acidobacteriota, within which (the bold character) had a significant difference along Hg gradients. Microbial functions and phenotype predicted with PICRUSt2 and Bugbase, nutrition and Hg stress induced related metabolism were enriched with elevated Hg. Altogether, these results indicate that the Hg pollution might have strong effects on rhizosphere microbiome functional structure and could provide fundamental and important data for utilizing rhizosphere technology to remediate Hg remediation
