Structure‐Driven α‐Fe ₂ O ₃ @Ag Nanohybrids Orchestrate Redox–Hormone–Metabolite Crosstalk for Plant Salt Stress Reprogramming

Soil salinity is a critical abiotic stressor that disrupts plant growth by impairing redox balance, membrane stability, and metabolic coordination. While nanomaterials have emerged as promising abiotic stress modulators, the influence of nanoscale architecture on multi-level plant responses remains insufficiently understood. Here, we report the design and application of pinwheel-like α-Fe₂O₃@Ag nanohybrids, engineered through controlled hydrolysis, ball milling, and high-temperature calcination, to reprogram salt stress responses across physiological and molecular scales. These hybrids exhibit hierarchical anisotropic structures that promote leaf adhesion, cellular uptake, and redox interface activity. Integrated multi-omics analyses reveal that α-Fe₂O₃@Ag enhances stress tolerance by modulating antioxidant defense, preserving photosynthetic efficiency, and rebalancing osmotic and hormonal pathways. At the molecular level, the nanohybrids induce transcriptomic and metabolomic rewiring across key axes, including unsaturated fatty acid metabolism, sulfur assimilation, hormone signaling (ABA and JA), and protein turnover. This study presents a structure-function-response framework linking nanomaterial morphology to biological outcomes, and highlights the potential of hybrid nanoregulators as versatile tools for enhancing crop resilience under environmental stress. The findings offer conceptual and practical advances for developing next-generation nano-enabled strategies in sustainable agriculture.