Cucumber (Cucumis sativus) plants were cultivated in hydroponic media with nano and bulk- iron oxide (Fe₃O₄) (50, 500 and 2000 mg/L) over a period of 21 days. At the low concentration (50 mg/L), nano-Fe₃O₄ resulted in reduction of biomass and enzyme activities compared to the control. However, at the higher concentration of nano-Fe₃O₄ dosage (2000 mg/L), there was a significant increase in biomass, antioxidant enzymes superoxide dismutase (SOD) and peroxidase (POD). In contrary, the high concentration of bulk-Fe₃O₄ caused phytotoxicity in terms of biomass and enzymes activity. The phytotoxicity was dependent on the particles property (mainly sizes and aggregation) for nano-F₃O₄ and concentration dependent for bulk-Fe₃O₄. The particle size is an important factor that can influence the bioavailability of nanomaterials, which need to be included when evaluating the exposure of nanomaterials and their deleterious effects in the environment. These promising results can help to develop the possible application of Fe₃O₄ NPs which may improve nutrient management to overcome food security.

将黄瓜（Cucumis sativus）植物在含有纳米氧化铁和块状氧化铁（Fe ₃ O ₄）（50、500和2000 mg / L）的水培培养基中培养21天。与对照相比，在低浓度（50 mg / L）下，纳米Fe ₃ O ₄导致生物量和酶活性降低。但是，在较高浓度的纳米Fe ₃ O ₄（2000 mg / L）下，生物量，抗氧化酶超氧化物歧化酶（SOD）和过氧化物酶（POD）显着增加。相反，高浓度的块状Fe ₃ O ₄在生物量和酶活性方面引起了植物毒性。植物毒性取决于纳米F ₃ O ₄的颗粒性质（主要是尺寸和聚集），而浓度取决于本体Fe ₃ O ₄。粒径是可能影响纳米材料生物利用度的重要因素，评估纳米材料的暴露及其在环境中的有害影响时必须包括在内。这些有希望的结果可以帮助开发Fe ₃ O ₄ NP的可能应用，从而可以改善营养管理以克服食品安全。