title: Citric acid enhances the phytoextraction of chromium, plant growth, and photosynthesis by alleviating the oxidative damages in Brassica napus L.
abstract: Chromium (Cr) toxicity is widespread in crops grown on Cr-contaminated soils and has become a serious environmental issue which requires affordable strategies for the remediation of such soils. This study was performed to assess the performance of citric acid (CA) through growing Brassica napus in the phytoextraction of Cr from contaminated soil. Different Cr (0, 100, and 500 μM) and citric acid (0, 2.5, and 5.0 mM) treatments were applied alone and in combinations to 4-week-old seedlings of B. napus plants in soil under wire house condition. Plants were harvested after 12 weeks of sowing, and the data was recorded regarding growth characteristics, biomass, photosynthetic pigments, malondialdehyde (MDA), electrolytic leakage (EL), antioxidant enzymes, and Cr uptake and accumulation. The results showed that the plant growth, biomass, chlorophyll contents, and carotenoid as well as soluble protein concentrations significantly decreased under Cr stress alone while these adverse effects were alleviated by application of CA. Cr concentration in roots, stem, and leaves of CA-supplied plant was significantly reduced while total uptake of Cr increased in all plant parts with CA application. Furthermore, in comparison with Cr treatments alone, CA supply reduced the MDA and EL values in both shoots and roots. Moreover, the activity of superoxide dismutase (SOD), guaiacol peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) in shoots and roots markedly increased by 100 μM Cr exposure, while decreased at 500 μM Cr stress. CA application enhanced the activities of antioxidant enzymes compared to the same Cr treatment alone. Thus, the data indicate that exogenous CA application can increase Cr uptake and can minimize Cr stress in plants and may be beneficial in accelerating the phytoextraction of Cr through hyper-accumulating plants such as B. napus.
authors: Department of Environmental Sciences and Engineering, Government College University, Allama Iqbal Road, Faisalabad, 38000, Pakistan.
authors: Sehar
authors: S
authors: Afshan
authors: Shafaqat
authors: S
authors: Ali
authors: Saima Aslam
authors: SA
authors: Bharwana
authors: Muhammad
authors: M
authors: Rizwan
authors: Mujahid
authors: M
authors: Farid
authors: Farhat
authors: F
authors: Abbas
authors: Muhammad
authors: M
authors: Ibrahim
authors: Muhammad Aamer
authors: MA
authors: Mehmood
authors: Ghulam Hasan
authors: GH
authors: Abbasi
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D001673:Biodegradation, Environmental / Q000187:drug effects; D029688:Brassica napus / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development* / Q000378:metabolism*; D002734:Chlorophyll / Q000378:metabolism; D002857:Chromium / Q000302:isolation & purification* / Q000378:metabolism; D019343:Citric Acid / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D010788:Photosynthesis / Q000187:drug effects*; D012989:Soil Pollutants / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D000975:Antioxidants; D012989:Soil Pollutants; D002857:Chromium; D002734:Chlorophyll; D019343:Citric Acid; D008315:Malondialdehyde