title: Assessing the bioremediation potential of arsenic tolerant bacterial strains in rice rhizosphere interface.
abstract: The arsenic tolerant bacterial strains Staphylococcus arlettae (NBRIEAG-6), Staphylococcus sp. (NBRIEAG-8) and Brevibacillus sp. (NBRIEAG-9) were tested for their roles in enhancing plant growth and induction of stress-related enzymes in rice (Oryza sativa L. cv. NDR-359) plants at two different concentrations, 30 and 15mg/kg of As(V) and As(III), respectively. An experiment was conducted to test the effect of these strains on plant growth promotion and arsenic uptake. We found 30%-40% reduction in total As uptake in bacteria-inoculated plants, with increased plant growth parameters compared to non-inoculated plants. Moreover, the bacteria-inoculated plants showed reduced activity of total glutathione (GSH) and glutathione reductase (GR) compared to their respective controls, which suggests the bacteria-mediated reduction of oxidative stress in plants. Thus, these strains were found to be beneficial in terms of the biochemical and physiological status of the plants under arsenic stress conditions. Furthermore, one-way ANOVA and principal component analysis (PCA) on enzymatic and non-enzymatic assays also revealed clear variations. The results support the distinction between control and treatments in both shoots and roots. Therefore, this study demonstrates the potential of rhizobacteria in alleviating arsenic stress in rice plants.
authors.affiliation: Eco-auditing Group, CSIR-National Botanical Research Institute, Lucknow 226001, India; Department of Biochemistry, Banaras Hindu University, Varanasi 221001, India. Electronic address: namratas108@gmail.com.
authors.forename: Namrata
authors.initials: N
authors.lastname: Singh
authors.affiliation: Eco-auditing Group, CSIR-National Botanical Research Institute, Lucknow 226001, India.
authors.forename: Shubhi
authors.initials: S
authors.lastname: Srivastava
authors.affiliation: Department of Biochemistry, Banaras Hindu University, Varanasi 221001, India.
authors.forename: Sushma
authors.initials: S
authors.lastname: Rathaur
authors.affiliation: Eco-auditing Group, CSIR-National Botanical Research Institute, Lucknow 226001, India. Electronic address: nanditasingh8@yahoo.co.in.
authors.forename: Nandita
authors.initials: N
authors.lastname: Singh
mesh_terms: D000222:Adaptation, Physiological; D001151:Arsenic / Q000378:metabolism* / Q000633:toxicity; D001419:Bacteria; D001673:Biodegradation, Environmental; D058675:Brevibacillus / Q000378:metabolism / Q000502:physiology; D005978:Glutathione / Q000378:metabolism; D012275:Oryza; D018384:Oxidative Stress; D058441:Rhizosphere; D012989:Soil Pollutants / Q000378:metabolism* / Q000633:toxicity; D013210:Staphylococcus / Q000502:physiology
chemical_list: D012989:Soil Pollutants; D005978:Glutathione; D001151:Arsenic
keywords: Antioxidative enzyme; Environmental contamination; Metals; Oryza sativa L.; Soil bacteria