Nano-priming with selenium nanoparticles reprograms seed germination, antioxidant defense, and phenylpropanoid metabolism to enhance Fusarium graminearum resistance in maize seedlings.

Introduction: Fusarium graminearum (F. graminearum) threatens maize through stem rot and deoxynivalenol (DON) contamination. Conventional approaches like chemical seed coatings are constrained by limited long-term efficacy and environmental concerns such as soil residue accumulation. In contrast, selenium nanoparticle (SeNP) priming provides a sustainable and economically viable strategy, minimizing ecological footprints through rapid elemental bioconversion while enhancing disease resistance in agricultural systems. However, nanotechnology applications synchronizing seed enhancement with pathogen resistance remain underexplored.

Objectives: The study aimed to establish SeNP as a nano-priming agent for dual improvement of seed vigor and disease resistance in maize.

Methods: Combining widely-targeted metabolomics, transcriptomics, and physiological assays, the study compared the physiological and biochemical differences as well as antioxidant levels among the water (control group) and groups treated with 5, 25, 50, 75, and 100 mg/L of SeNP. The optimal concentration for SeNP priming was determined to be 50 mg/L. Disease resistance was subsequently analyzed based on this optimal concentration in comparison to the control group.

Results: SeNP accelerated the conversion of starch-to-sugar and elevated glycolytic-TCA cycle flux. SeNP-priming activated JA signaling to redirect phenylpropanoid metabolites to phenolic acids (↑1.3-fold), correlating with 26.3 % reduced disease severity and 42.5 % lower DON biosynthesis (p < 0.05).

Conclusion: This study found that 50 mg/L SeNPs priming can enhance the quality and antioxidant capacity of maize, reduce the contamination of F. graminearum and toxins, and provide an eco-friendly alternative to chemical treatment for mycotoxin control.