title: In vitro assessment of physiological changes of watermelon (Citrullus lanatus) upon iron oxide nanoparticles exposure.
abstract: With the rapid development of nanotechnology, developing nano iron fertilizer is an important strategy to alleviate Fe deficiency and elevate Fe fertilization effect in agricultural applications. In this study, watermelon seedlings were grown in soil amended with iron oxide nanoparticles (γ-Fe2O3NPs) at different concentrations (0, 20, 50, 100 mg/L). The content of soluble sugar and protein, content of chlorophyll and malondialdehyde (MDA), and activity of antioxidant enzymes of watermelon leaves were determined in five successive weeks to evaluate the physiological changes of watermelon plants after γ-Fe2O3NPs exposure. Transmission electron microscope (TEM) observations indicated that γ-Fe2O3NPs could enter root cell of watermelon. Results showed that 20 mg/L γ-Fe2O3NPs didn't cause any oxidative stress on watermelon and 50 mg/L γ-Fe2O3NPs could increase soluble sugar, soluble protein and chlorophyll content in the growth of plants. In addition, 50 and 100 mg/L γ-Fe2O3NPs caused oxidative stress on watermelon leaves, but this NP-induced stress was removed with the growth of watermelon. It is noteworthy that we found γ-Fe2O3NPs might possess an intrinsic peroxidase-like activity. The variation trend of physiological parameters was correlated with the nutritional requirements of plants. It can be concluded that γ-Fe2O3NPs at proper concentrations have the ability to improve iron deficiency chlorosis and promote the growth of watermelon plants. To the best of the author's knowledge, this is the first holistic study focusing on the impact of γ-Fe2O3NPs in long-term experiment of watermelon plants.
authors: Institute of Economic Crops, Hubei Academy of Agricultural Science, Wuhan 430064, People's Republic of China.
authors: Yunqiang
authors: Y
authors: Wang
authors: School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, People's Republic of China.
authors: Jing
authors: J
authors: Hu
authors: Institute of Economic Crops, Hubei Academy of Agricultural Science, Wuhan 430064, People's Republic of China.
authors: Zhaoyi
authors: Z
authors: Dai
authors: School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, People's Republic of China. Electronic address: lijunli0424@sina.com.
authors: Junli
authors: J
authors: Li
authors: School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, People's Republic of China.
authors: Jin
authors: J
authors: Huang
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D029773:Citrullus / Q000187:drug effects* / Q000502:physiology*; D005290:Ferric Compounds / Q000008:administration & dosage / Q000494:pharmacology* / Q000633:toxicity; D005308:Fertilizers; D000090463:Iron Deficiencies; D008315:Malondialdehyde / Q000378:metabolism; D053768:Metal Nanoparticles / Q000008:administration & dosage / Q000633:toxicity; D046529:Microscopy, Electron, Transmission; D009005:Monosaccharides; D018384:Oxidative Stress / Q000187:drug effects; D010544:Peroxidases / Q000378:metabolism; D018515:Plant Leaves / Q000187:drug effects; D010940:Plant Proteins / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000648:ultrastructure; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D005290:Ferric Compounds; D005308:Fertilizers; D009005:Monosaccharides; D010940:Plant Proteins; D002734:Chlorophyll; C000499:ferric oxide; D008315:Malondialdehyde; D010544:Peroxidases; D002374:Catalase; D013482:Superoxide Dismutase
keywords: Physiological changes; Watermelon; γ-Fe(2)O(3) NPs