Physiological and molecular responses of wheat following the foliar application of Iron Oxide nanoparticles

This study investigates the possible effects of iron oxide nanoparticles (FeNPs) on plant growth, expression of bZIP, DREB, and WRKY1, and biofortification efficacy in wheat (Triticum aestivum). The seedlings were treated with bulk iron oxide (bulk-Fe) or FeNPs at 100, 200, 300, and 400 mgL^-1. FeNPs significantly improved the fresh and dry weights of shoot and root compared to the control. Likewise, different concentrations of bulk-Fe caused an increase in biomass accumulation in shoot and root. Moreover, Fe content was increased in response to the foliar application of FeNPs and bulk-Fe. The expression of bZIP, DREB, and WRKY1 in the FeNP-treated plants was markedly up-regulated compared to the control. The increase in Fe contents and biomass, as well as upregulation in bZIP, DREB, and WRKY1 genes, indicate that FeNPs could be a promising strategy to encounter iron deficiency in the human diet and to improve plant protection against biotic and abiotic stress conditions.