Potential impact of iron oxide conjugated nano-fertilizer on growth, flowering and isozyme expression in Gardenia jasminoides

Nano-fertilizers protect the soil from the excessive addition of traditional fertilizers, enhancing the efficiency of the elements and diminishing the number of additive fertilizers. The effect of Fe2O3NPs-Boron (Fe2O3NPs-B), and Fe2O3 NP-Humic Acid (Fe2O3NPs-HA) at 100, 150 and 250 ppm, Fe2O3, and control (without any iron fertilizers) on the vegetative growth, flowering, photosynthetic pigments, nutrient element content and isozymes activity (peroxidase, superoxide dismutase and polyphenol oxide) of Gardenia jasminoides plants was investigated. Gamma-rays at 25 kGy were conducted for the promising synthesis of Fe2O3NPs-B, and Fe2O3NPs-HA. The experiment was carried out under greenhouse conditions during two successive seasons. The results stated that Fe2O3NPs-B and Fe2O3NPs-HA at the highest concentration (250 ppm) had a significant positive effect in all vegetative characteristics, photosynthetic pigments, nutrient element content and isozymes activity. Fe2O3NPs-HA showed the optimal result in all morphological and biochemical characteristics. The highest activity of enzymes appeared in the treated plants with Fe2O3 NPs-B followed by Fe2O3 NPs-HA at 250 ppm. The advantage nano-fertilizer usage may be summarized as saving the soil from the unreasonable accumulation of classic fertilizers, improving the use efficiency of parts and reducing the number of different fertilizers as a consequence of their increased surface area and their nano-size.