Plant–Microbiome Interactions for Environmental Resilience: Rhizosphere Ecology, Climate Adaptation and Ecosystem Sustainability

Rising temperatures, more erratic rainfall and expanding soil salinisation are eroding the stability of cropping systems, and the microbial communities inhabiting the rhizosphere have been proposed as a tractable lever for restoring that stability. Three research programmes now dominate this ambition: the assembly of defined synthetic communities from culturable isolates, the exploitation of host genetic variation that shapes microbial recruitment, and the computational or synthetic-biology design of microbial functions targeted at specific agronomic outcomes. These programmes have developed largely in parallel, are evaluated against different standards of proof, and are frequently presented in a common narrative of imminent application that the underlying evidence does not yet support. This review critically examines the strength, consistency and translational maturity of the evidence in each programme and interrogates the assumptions that connect them. Peer-reviewed literature published between January 2012 and 27 July 2026 was identified through structured searching of biomedical, agricultural and multidisciplinary scholarly indexes, complemented by backward and forward citation tracking and verification of bibliographic identity through a digital object identifier registry. Evidence was appraised for design adequacy, environmental realism, replication and the distance between mechanistic demonstration and field performance. The synthesis indicates that host genetic effects on rhizosphere community composition are statistically detectable but generally modest relative to soil and environmental effects, that single-locus exemplars have been disproportionately influential in shaping expectations, and that synthetic communities reliably establish causality under controlled conditions while rarely demonstrating durable colonisation or yield benefit in the field. Reported successes cluster in a small number of model species, glasshouse systems and short observation windows, and negative or equivocal results appear underrepresented. Confidence is highest for mechanistic claims about exudate-mediated recruitment and lowest for claims about transferable, climate-buffering performance at agronomic scale. Progress will depend less on additional descriptive surveys than on multi-environment trials, quantitative measurement of strain persistence, pre-registered field evaluation and explicit treatment of ecological containment.