Architecting seed resilience: a safe-by-design and microplastic-free nanoenabled framework for advanced seed priming and sustainable agriculture

Traditional seed coating technologies continue to use petroleum-based synthetic polymers as a seed coating material, which are causing microplastic pollution, which are unable to precisely deliver the active ingredients simultaneously under abiotic and biotic stress. While nanoenabled and biopolymer films have been extensively investigated, the majority of the available reviews are still descriptive and fail to provide an integrative approach that relates the design of materials with seed physiology, process engineering and regulatory readiness. This review aims to fill this gap by discussing microplastic-free nanoenabled seed priming platforms such as bio-based electrospun nanofibers, peptide-functionalized carriers, plant-derived extracellular vesicles, and stimuli-responsive smart biopolymers. We look at the modulation of ROS, hormonal signalling, stress memory and the seed microbiome in these systems and evaluate the technology readiness level, scale-up challenges and analytical needs. There are three significant gaps identified, lack of quantitative understanding of the polymer-seed interface; lack of multi-location field validation; and regulatory issues for advanced bio-platforms. We discuss that this will be achieved by implementing a safe-by-design roadmap, with standardized characterization protocols, long-term field testing with dose–response designs, and harmonized regulatory processes. The creation of molecular design, its translation to practices and sustainable agriculture targets makes the route of microplastic-free nano-priming an appealing one to address SDG 2, SDG 12 and SDG 13, climate-resilient and climate-friendly agriculture.