Symbiotic Nodulation Enhances Legume Tolerance to Abiotic Stresses: Mechanisms and Perspectives

Abiotic stresses, such as drought, salinity, heavy metal contamination and cold, pose significant challenges to global agriculture, reducing crop productivity and threatening food security. Legume-rhizobium symbiosis not only facilitates biological nitrogen fixation but also improves plant tolerance to abiotic stresses. Nodulated leguminous plants exhibit better growth and improved productivity under abiotic stress conditions. In this review, we highlight recent advances in understanding how symbiotic nodulation mitigates abiotic stresses, focusing on physiological and biochemical responses, as well as molecular pathways. We then discuss future research directions to optimise rhizobial applications for stress-tolerant and climate-adaptive farming systems. Rhizobial inoculation is presented as a promising, sustainable and eco-friendly strategy for mitigating abiotic stresses, offering significant potential for stressed agricultural systems.