Iron Oxide Nanoparticles as a Potential Iron Fertilizer for Peanut (Arachis hypogaea)

Nanomaterials are used in practically every aspect of modern life, including agriculture. The aim of this study was to evaluate the effectiveness of iron oxide nanoparticles (Fe(2)O(3) NPs) as a fertilizer to replace traditional Fe fertilizers, which have various shortcomings. The effects of the Fe(2)O(3) NPs and a chelated-Fe fertilizer (ethylenediaminetetraacetic acid-Fe; EDTA-Fe) fertilizer on the growth and development of peanut (Arachis hypogaea), a crop that is very sensitive to Fe deficiency, were studied in a pot experiment. The results showed that Fe(2)O(3) NPs increased root length, plant height, biomass, and SPAD values of peanut plants. The Fe(2)O(3) NPs promoted the growth of peanut by regulating phytohormone contents and antioxidant enzyme activity. The Fe contents in peanut plants with Fe(2)O(3) NPs and EDTA-Fe treatments were higher than the control group. We used energy dispersive X-ray spectroscopy (EDS) to quantitatively analyze Fe in the soil. Peanut is usually cultivated in sandy soil, which is readily leached of fertilizers. However, the Fe(2)O(3) NPs adsorbed onto sandy soil and improved the availability of Fe to the plants. Together, these results show that Fe(2)O(3) NPs can replace traditional Fe fertilizers in the cultivation of peanut plants. To the best of our knowledge, this is the first research on the Fe(2)O(3) NPs as the iron fertilizer.