Metagenomic insights into the interaction between the rhizosphere microbiome and traditional variety Huaxi hot pepper

• The organic manure improved pepper height, fresh weight, fruit yield and quality. • The organic manure can enhance the activities of CAZymes cellulase. • Five CAZyme gene were closely positively related to the rhizosphere organic carbon. • CAZyme cellulase deepen associations between the microbial community and the pepper. • Explaining functional CAZyme genes regulate in the traditional pepper rhizosphere. Rhizosphere microorganisms play a crucial role in regulating plant growth and development. Huaxi hot pepper is a common vegetable favored by the locals in Guiyang city (China), the structure and composition of whose rhizosphere microbes and associated functional genes remain underexplored. Based on a metagenomic strategy, four fertilization treatments were carried out to explore the interactions between rhizosphere microbes and hot pepper plants. The results showed that the organic manure (ORMA) treatment improved the pepper height and fresh weight as well as fruit yield and quality, microbial diversity Chao1 in ORMA was significantly higher than other treatments, and significant taxonomic dissimilarities of some microbial communities were found. The five most dominant microbial phyla were Pseudomonadota, Acidobacteriota, Actinomycetota, Chloroflexota, and Gemmatimonadota. In addition, 23 dominant bacterial genera with relative abundances > 1 % and 93 carbohydrate-active enzyme (CAZyme) genes derived from microbes were detected, among which Pseudomonas, Ramlibacter, Sphingomonas , and Variovorax , as well as glycoside hydrolases (GH) (GH115, GH20, and GH37) as well as glycosyl transferases (GT) (GT4 and GT41) were significantly associated with plant growth and both fruit yield and quality based on Pearson correlation and Two-way analysis. The results indicated that the presence of soil microbes and their extracellular CAZymes had a positive effect on pepper performances. Importantly, this study may support references to further investigate beneficial soil microbes, which promote the yield and quality of the other vegetables.