Improved iron use efficiency in tomato using organically coated iron oxide nanoparticles as efficient bioavailable Fe sources

Abstract

BackgroundIron [Fe] deficiency is one of the nutritional issues of plants, especially in calcareous soils in which iron-fertilizers are used to solve this obstacle. Due to the pivotal role of iron, the introduction of efficient, cost-effective, and eco-friendly strategies is necessary to prevent its deficiency in plants. The nanoparticle-based formulations may provide efficient bioavailability, subsequently, reduce the amount of the required dosage of nutrients for extended periods, and decrease the environmental risks.ResultsIn this study, the effects of different iron nanoparticles (NPs) including Fe3O4 nanoparticles (Fe3O4), citric acid coated Fe3O4 nanoparticles (Fe3O4@CA), humic acid coated Fe3O4 nanoparticles (Fe3O4@HA), and EDTA coated nanoparticles (Fe3O4@EDTA) were investigated as iron [Fe] sources on the vegetative growth and physiological parameters of tomato as a model plant in a soil system. The experimental results showed that the organically coated Fe3O4 NPs significantly increased the amount of [Fe] in the shoot and enhanced its growth. The highest and lowest amount of [Fe] was observed in the Fe3O4@HA NPs and control treatments, respectively. In addition, using organically coated Fe3O4 NPs, especially Fe3O4@HA increased plant growth and yield.ConclusionsThis study showed that using organically coated Fe3O4 NPs is promising for plant nutritional supplementation. In particular, the humic acid-coated Fe3O4 nanoparticles (Fe3O4@HA) were determined to be the most promising, due to more benefits for plant growth and yield compared to Fe3O4 NPs. Therefore, Fe3O4@HA nanofertilizer can be introduced as an inexpensive, effective, bioavailable, and biocompatible option to address [Fe] deficiency in the soil.Graphical