Rhizosphere microbiomes altered by environmental stresses and agronomic practices: Implications for plant adaptation and soil biogeochemical processes

The soil microbiome is increasingly recognized not merely as a respondent to its environment, but as an active engineer of soil health and plant resilience. However, while most research focuses on how agronomic practices and environmental stresses alter microbial communities, the reciprocal feedback, how these reshaped microbiomes in turn modify critical soil properties, remains a key knowledge gap. This review synthesizes recent literature to bridge this gap, systematically connecting external pressures (stresses and practices) to the resulting impacts on soil biogeochemistry via the plant-microbe nexus. Our analysis reveals three main findings: (1) Under stress, plant precisely tailor root exudate chemistry to recruit specific microbial allies capable of enhancing stress tolerance. (2) This functionally distinct microbiome then actively re-engineers the soil, measurably improving soil aggregation, carbon sequestration, and nutrient availability. (3) Agronomic practices, such as no-till and cover cropping, serve as powerful tools to steer these interactions, creating a positive feedback loop that builds long-term soil fertility. We conclude that managing this plant-microbe-soil feedback system is fundamental for developing agricultural strategies that simutaneously boost crop productivity and regenerate soil health.