Advances in rhizobial technology: driving sustainable agriculture in the 21 st century

Rhizobial technology has become a transformative tool for environmentally friendly and sustainable agriculture. Rhizobia are key nitrogen-fixing bacteria that enhance soil fertility and reduce reliance on synthetic nitrogen fertilisers. In addition to nitrogen fixation, they act as effective plant growth promoters by producing phytohormones, mobilising nutrients, and improving root development. Advances in bioinoculant engineering now support efficient symbiotic associations in both leguminous and non-leguminous crops, offering a green strategy to boost agricultural productivity. Rhizobia also help plants withstand abiotic and biotic stresses, and many strains display strong biocontrol abilities by producing antimicrobial compounds and suppressing phytopathogens. However, their field performance can be inconsistent due to poor survival during storage, competition with native microbes, environmental conditions, and limited farmer awareness. To overcome these challenges, strategies such as co-inoculation with compatible microbes, encapsulated formulations, genetic enhancement, improved agronomic practices, pathogen management, and farmer awareness are being developed to increase inoculant stability and effectiveness. Overall, rhizobial technology serves as a cornerstone of smart, sustainable farming, supporting food security, environmental protection, and the restoration of soil health for future green agriculture.