title: Increased growth and root Cu accumulation of Sorghum sudanense by endophytic Enterobacter sp. K3-2: Implications for Sorghum sudanense biomass production and phytostabilization.
abstract: Endophytic bacterial strain K3-2 was isolated from the roots of Sorghum sudanense (an bioenergy plant) grown in a Cu mine wasteland soils and characterized. Strain K3-2 was identified as Enterobacter sp. based on 16S rRNA gene sequence analysis. Strain K3-2 exhibited Cu resistance and produced 1-aminocyclopropane-1-carboxylate (ACC) deaminase, indole-3-acetic acid (IAA), siderophores, and arginine decarboxylase. Pot experiments showed that strain K3-2 significantly increased the dry weight and root Cu accumulation of Sorghum sudanense grown in the Cu mine wasteland soils. Furthermore, increase in total Cu uptake (ranging from 49% to 95%) of the bacterial inoculated-Sorghum sudanense was observed compared to the control. Notably, most of Cu (83-86%) was accumulated in the roots of Sorghum sudanense. Furthermore, inoculation with strain K3-2 was found to significantly increase Cu bioconcentration factors and the proportions of IAA- and siderophore-producing bacteria in the root interiors and rhizosphere soils of Sorghum sudanense compared with the control. Significant decrease in the available Cu content was also observed in the rhizosphere soils of the bacterial-inoculated Sorghum sudanense. The results suggest that the endophytic bacterial strain K3-2 may be exploited for promoting Sorghum sudanense biomass production and Cu phytostabilization in the Cu mining wasteland soils.
authors.affiliation: Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, People's Republic of China.
authors.forename: Ya
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, People's Republic of China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, People's Republic of China.
authors.forename: Lu
authors.initials: L
authors.lastname: Wang
authors.affiliation: Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, People's Republic of China.
authors.forename: Lin-Yan
authors.initials: LY
authors.lastname: He
authors.affiliation: Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, Jiangsu, People's Republic of China. Electronic address: xfsheng@njau.edu.cn.
authors.forename: Xia-Fang
authors.initials: XF
authors.lastname: Sheng
mesh_terms: D001673:Biodegradation, Environmental; D018533:Biomass; D019755:Carbon-Carbon Lyases / Q000378:metabolism; D003300:Copper / Q000378:metabolism*; D024881:Drug Resistance, Bacterial; D060026:Endophytes / Q000302:isolation & purification / Q000502:physiology*; D004754:Enterobacter / Q000302:isolation & purification / Q000502:physiology*; D007210:Indoleacetic Acids / Q000378:metabolism; D008906:Mining; D018517:Plant Roots / Q000254:growth & development / Q000378:metabolism / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D058441:Rhizosphere; D017262:Siderophores; D012987:Soil; D012989:Soil Pollutants / Q000378:metabolism*; D045868:Sorghum / Q000254:growth & development / Q000378:metabolism / Q000382:microbiology*
chemical_list: D007210:Indoleacetic Acids; D012336:RNA, Ribosomal, 16S; D017262:Siderophores; D012987:Soil; D012989:Soil Pollutants; C030737:indoleacetic acid; D003300:Copper; C033634:1-aminocyclopropane-1-carboxylate deaminase; D019755:Carbon-Carbon Lyases
keywords: Bioconcentration factor; Copper mining wasteland; Cu-resistant endophytic Enterobacter sp. K3-2; Phytostabilization; Sorghum sudanense