title: Effect of cadmium stress and inoculation with a heavy-metal-resistant bacterium on the growth and enzyme activity of Sorghum bicolor.
abstract: In this study, the influence of the heavy-metal-resistant rhizobacterial inoculant Rhodococcus ruber N7 on the growth and enzyme activity of Sorghum bicolor (L.) Moench. under cadmium stress was investigated in quartz sand pot experiments. The effect of cadmium and bacterium on the plant biomass accumulation, photosynthetic pigments, protein content, and the activities of plant-tissue enzymes such as peroxidase, laccase, and tyrosinase were estimated. It was shown that the presence of cadmium in the sand influenced the roots to a greater extent than it influenced the aerial parts of sorghum. This is manifested as increased protein content, reduced activity of peroxidase, and increased activity of laccase. Compared with cadmium stress, inoculation of plants with rhizobacterium R. ruber N7 has a stronger (and often opposite) effect on the biochemical parameters of sorghum, including a decrease in the concentration of protein in the plant, but increased the activity of peroxidase, laccase, and tyrosinase. Under cadmium contamination of sand, R. ruber N7 successfully colonizes the roots of Sorghum bicolor, survives in its root zone, and contributes to the accumulation of the metal in the plant roots, thereby reducing the concentration of the pollutant in the environment.
authors.affiliation: Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, 13 Prospekt Entuziastov, Saratov, Russia, 410049. amuratova@yahoo.com.
authors.forename: Anna
authors.initials: A
authors.lastname: Muratova
authors.affiliation: Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, 13 Prospekt Entuziastov, Saratov, Russia, 410049.
authors.forename: Yelena
authors.initials: Y
authors.lastname: Lyubun
authors.affiliation: Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, 13 Prospekt Entuziastov, Saratov, Russia, 410049.
authors.forename: Kristina
authors.initials: K
authors.lastname: German
authors.affiliation: Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, 13 Prospekt Entuziastov, Saratov, Russia, 410049.
authors.forename: Olga
authors.initials: O
authors.lastname: Turkovskaya
mesh_terms: D018533:Biomass; D002104:Cadmium / Q000378:metabolism / Q000633:toxicity*; D019216:Metals, Heavy / Q000737:chemistry; D014442:Monophenol Monooxygenase / Q000378:metabolism; D009195:Peroxidase / Q000378:metabolism; D010544:Peroxidases / Q000378:metabolism*; D010788:Photosynthesis / Q000187:drug effects; D010940:Plant Proteins / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D012240:Rhodococcus / Q000502:physiology*; D055051:Salt-Tolerant Plants / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development / Q000382:microbiology; D045868:Sorghum / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development / Q000382:microbiology
chemical_list: D019216:Metals, Heavy; D010940:Plant Proteins; D002104:Cadmium; D010544:Peroxidases; D009195:Peroxidase; D014442:Monophenol Monooxygenase
keywords: Cadmium; Laccase; Peroxidase; Rhodococcus ruber; Sorghum bicolor