<b>Rhizosphere Microbiology: Mechanisms, Agricultural Applications, and Future Prospects</b>

Abstract

The rhizosphere is the narrow zone of soil surrounding plant roots that harbours highly diverse and metabolically active microbial communities. This review synthesises current knowledge on rhizosphere microbiology and its implications for sustainable, climate-smart agriculture, with emphasis on the Nigerian context. The taxonomic diversity of rhizosphere microorganisms is examined, encompassing bacteria, fungi, archaea, viruses, and protozoa, alongside functional mechanisms including plant growth promotion, nutrient solubilisation, biological nitrogen fixation, and soilborne pathogen suppression. Agricultural applications reviewed include biofertilisers, biocontrol agents, biostimulants, and synthetic microbial communities (SynComs), alongside management practices such as conservation agriculture and organic amendments. Emerging rhizosphere engineering strategies, including holobiont breeding, CRISPR-based plant modification, and microbiome transplantation, are critically assessed. Key challenges regarding field consistency, formulation, shelf life, and regulatory frameworks are identified, with targeted recommendations for sub-Saharan African contexts. This narrative review searched PubMed, Web of Science, Scopus, and Google Scholar for a minimum of 60 peer-reviewed literature published between 2019 and 2025, with selected foundational studies included where necessary.