title: Improvement in phytoremediation potential of Solanum nigrum under cadmium contamination through endophytic-assisted Serratia sp. RSC-14 inoculation.
abstract: The growth of hyperaccumulator plants is often compromised by increased toxicity of metals like cadmium (Cd). However, extraction of such metals from the soil can be enhanced by endophytic microbial association. Present study was aimed to elucidate the potential of microbe-assisted Cd phytoextraction in hyperaccumulator Solanum nigrum plants and their interactions under varied Cd concentrations. An endophytic bacteria Serratia sp. RSC-14 was isolated from the roots of S. nigrum. In addition to Cd tolerance up to 4 mM, the RSC-14 exhibited phosphate solubilization and secreted plant growth-promoting phytohormones such as indole-3-acetic acid (54 μg/mL). S. nigrum plants were inoculated with RSC-14 and were grown in different concentrations of Cd (0, 10, and 30 mg Cd kg(-1) sand). Results revealed that Cd treatment caused significant cessation in plant growth, biomass, and chlorophyll content, whereas significantly higher malondialdehyde (MDA) and electrolyte production in leaves were observed in a dose-dependent manner. Conversely, RSC-14 inoculation relived the toxic effects of Cd-induced stress by significantly increasing root/shoot growth, biomass production, and chlorophyll content and decreasing MDA and electrolytes contents. Ameliorative effects on host growth were also observed by the regulation of metal-induced oxidative stress enzymes such as catalase, peroxidase, and polyphenol peroxidase. Activities of these enzymes were significantly reduced in RSC-14 inoculated plants as compared to control plants under Cd treatments. The lower activities of stress responsive enzymes suggest modulation of Cd stress by RSC-14. The current findings support the beneficial uses of Serratia sp. RSC-14 in improving the phytoextraction abilities of S. nigrum plants in Cd contamination.
authors.affiliation: School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu, 702-701, Republic of Korea.
authors.forename: Abdur Rahim
authors.initials: AR
authors.lastname: Khan
authors.forename: Ihsan
authors.initials: I
authors.lastname: Ullah
authors.forename: Abdul Latif
authors.initials: AL
authors.lastname: Khan
authors.forename: Gun-Seok
authors.initials: GS
authors.lastname: Park
authors.forename: Muhammad
authors.initials: M
authors.lastname: Waqas
authors.forename: Sung-Jun
authors.initials: SJ
authors.lastname: Hong
authors.forename: Byung Kwon
authors.initials: BK
authors.lastname: Jung
authors.forename: Yunyoung
authors.initials: Y
authors.lastname: Kwak
authors.forename: In-Jung
authors.initials: IJ
authors.lastname: Lee
authors.forename: Jae-Ho
authors.initials: JH
authors.lastname: Shin
mesh_terms: D000222:Adaptation, Physiological; D001673:Biodegradation, Environmental; D002104:Cadmium / Q000378:metabolism*; D060026:Endophytes / Q000378:metabolism*; D018515:Plant Leaves / Q000254:growth & development / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D018517:Plant Roots / Q000254:growth & development / Q000378:metabolism; D012705:Serratia / Q000378:metabolism*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000378:metabolism*; D032324:Solanum nigrum / Q000254:growth & development / Q000378:metabolism*; D013312:Stress, Physiological
chemical_list: D010940:Plant Proteins; D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium