Suppressing radiocesium uptake and root-to-shoot translocation in crops: Molecular, agronomic, and ecological strategies

Radiocesium (r-Cs: 137 Cs) from the Fukushima Daiichi accident and earlier nuclear fallout remains a long-term contaminant in agricultural soils. It poses an ongoing threat to global food safety because crops readily absorb it as a potassium analog. This review synthesizes a decade of mechanistic, agronomic, and ecological advances in suppressing r-Cs uptake and root-to-shoot translocation. First, the impact of soil mineralogy, particularly clay fixation, on initial r-Cs bioavailability is examined. At the molecular level, r-Cs influx is governed by a shared calcium-signaling hub linked to potassium status. Consequently, optimizing potassium fertilization can transcriptionally silence the principal uptake genes. Furthermore, controlling xylem loading and managing internal sodium interactions directly restrict r-Cs translocation, protecting edible plant parts. Supplementary countermeasures, including plant-microbe symbioses, porous soil amendments, and targeted genetic exclusions, are also evaluated. To ensure long-term agricultural resilience, multi-site field trials and the molecular dissection of translocation pathways must be prioritized in future research. Ultimately, sustainable crop production requires integrating biological and agronomic strategies rather than relying solely on intensive potassium fertilization.