title: Effect of lead on phytotoxicity, growth, biochemical alterations and its role on genomic template stability in Sesbania grandiflora: a potential plant for phytoremediation.
abstract: The present study was aimed at evaluating phytotoxicity of various concentrations of lead nitrate (0, 100, 200, 400, 600, 800 and 1000mgL(-1)) in Sesbania grandiflora. The seedling growth was significantly affected (46%) at 1000mgL(-1) lead (Pb) treatment. Accumulation of Pb content was high in root (118mgg(-1) dry weight) than in shoot (23mgg(-1) dry weight). The level of photosynthetic pigment contents was gradually increased with increasing concentrations of Pb. Malondialdehyde (MDA) content increased in both the leaves as well as roots at 600mgL(-1) Pb treatment and decreased at higher concentrations. The activity of antioxidative enzymes such as superoxide dismutase and peroxidase were positively correlated with Pb treatment while catalase and ascorbate peroxidase activities increased up to 600mgL(-1) Pb treatment and then slightly decreased at higher concentrations. Isozyme banding pattern revealed the appearance of additional isoforms of superoxide dismutase and peroxidase in Pb treated leaf tissues. Isozyme band intensity was more consistent with the respective changes in antioxidative enzyme activities. Random amplified polymorphic DNA results indicated that genomic template stability (GTS) was significantly affected based on Pb concentrations. The present results suggest that higher concentrations of Pb enhanced the oxidative damage by over production of ROS in S. grandiflora that had potential tolerance mechanism to Pb as evidenced by increased level of photosynthetic pigments, MDA content, and the level of antioxidative enzymes. Retention of high levels of Pb in root indicated that S. grandiflora has potential for phytoextracting heavy metals by rhizofiltration.
authors.affiliation: Plant Genetic Engineering and Molecular Biotechnology Lab, Department of Biotechnology, Periyar University, Salem 636011, TN, India.
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Malar
authors.affiliation: Plant Genetic Engineering and Molecular Biotechnology Lab, Department of Biotechnology, Periyar University, Salem 636011, TN, India.
authors.forename: Rajendiran
authors.initials: R
authors.lastname: Manikandan
authors.affiliation: School of Life Sciences and Environment, University of Trás-os-Montes Alto Douro, Apartado 1013, 5001-801 Vila Real, Portugal.
authors.forename: Paulo J C
authors.initials: PJ
authors.lastname: Favas
authors.affiliation: Department of Biology, Western Kentucky University, Bowling Green, KY 42101, USA.
authors.forename: Shivendra
authors.initials: S
authors.lastname: Vikram Sahi
authors.affiliation: Plant Genetic Engineering and Molecular Biotechnology Lab, Department of Biotechnology, Periyar University, Salem 636011, TN, India. Electronic address: pvenkat67@yahoo.com.
authors.forename: Perumal
authors.initials: P
authors.lastname: Venkatachalam
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D060387:Ascorbate Peroxidases / Q000378:metabolism; D001673:Biodegradation, Environmental; D002374:Catalase / Q000378:metabolism; D020869:Gene Expression Profiling; D018745:Genome, Plant; D023281:Genomics; D008658:Inactivation, Metabolic; D007854:Lead / Q000378:metabolism / Q000493:pharmacokinetics / Q000633:toxicity*; D015227:Lipid Peroxidation / Q000187:drug effects; D008315:Malondialdehyde / Q000378:metabolism*; D009566:Nitrates / Q000378:metabolism / Q000493:pharmacokinetics / Q000633:toxicity*; D010788:Photosynthesis / Q000187:drug effects; D010860:Pigments, Biological / Q000378:metabolism*; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000378:metabolism; D049931:Sesbania / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D009566:Nitrates; D010860:Pigments, Biological; D007854:Lead; D008315:Malondialdehyde; C017461:lead nitrate; D060387:Ascorbate Peroxidases; D002374:Catalase; D013482:Superoxide Dismutase
keywords: DNA damage; Genotoxicity; Lead toxicity; Oxidative stress; Phytoremediation; Sesbania grandiflora