Exogenous rutin ameliorates NaCl‑induced inhibition of Fagopyrum esculentum germination and early growth.

backgroundSoil salinity is a pervasive threat to global agriculture, severely impairing the germination of salt-sensitive crops like common buckwheat (Fagopyrum esculentum). While natural flavonoids such as rutin are recognized for their potent antioxidant properties, their application as stress mitigators often relies on an incomplete mechanistic understanding. The literature currently lacks a systematic, quantitative assessment of how exogenous rutin orchestrates the interplay between antioxidant defenses, osmotic adjustment, and membrane stability to protect buckwheat during its most vulnerable germination stage, a gap that limits the development of effective, nature-based agricultural strategies. Here, we address this gap using a comprehensive physiological approach.

resultsSeeds from three buckwheat varieties were subjected to 200 mM NaCl stress with or without 1.5 mM rutin pretreatment. Rutin application dramatically reversed salt-induced germination inhibition, boosting the germination rate by up to 258%. Mechanistically, rutin significantly amplified the plant's antioxidant enzyme machinery to effectively scavenge key reactive oxygen species like superoxide and hydrogen peroxide, while concurrently promoting the accumulation of protective osmolytes. This culminated in markedly reduced lipid peroxidation, measured as malondialdehyde content, and preserved cell membrane integrity.

conclusionsWe conclude that exogenous rutin operates not through a single mode of action, but by orchestrating a synergistic enhancement of the plant's intrinsic antioxidant and osmotic defense systems. This integrated defense converges to maintain membrane stability, providing a robust mechanistic framework that validates rutin's use as an effective biostimulant to enhance crop resilience in saline environments.