TY - JOUR
T1 - Plant Growth-Promoting Traits in Rhizobacteria of Heavy Metal-Resistant Plants and Their Effects on Brassica nigra Seed Germination
AU - ROMÁN-PONCE, Brenda
AU - REZA-VÁZQUEZ, Diana Miryel
AU - GUTIÉRREZ-PAREDES, Sonia
AU - DE HARO-CRUZ, María de Jesús
AU - MALDONADO-HERNÁNDEZ, Jessica
AU - BAHENA-OSORIO, Yanely
AU - ESTRADA-DE LOS SANTOS, Paulina
AU - WANG, En Tao
AU - VÁSQUEZ-MURRIETA, María Soledad
N1 - Publisher Copyright:
© 2017 Soil Science Society of China
PY - 2017/6
Y1 - 2017/6
N2 - Phytoremediation is an emerging technology that uses plants and their associated microbes to clean up pollutants from the soil, water, and air. In order to select the plant growth-promoting rhizobacteria (PGPR) for phytoremediation of heavy metal contamination, 60 bacterial strains were isolated from the rhizosphere of two endemic plants, Prosopis laevigata and Spharealcea angustifolia, in a heavy metal-contaminated zone in Mexico. These rhizobacterial strains were characterized for the growth at different pH and salinity, extracellular enzyme production, solubilization of phosphate, heavy metal resistance, and plant growth-promoting (PGP) traits, including production of siderophores and indol-3-acetic acid (IAA). Overall, the obtained rhizobacteria presented multiple PGP traits. These rhizobacteria were also resistant to high levels of heavy metals (including As as a metalloid) (up to 480 mmol L−1 As(V), 24 mmol L−1 Pb(II), 21 mmol L−1 Cu(II), and 4.5 mmol L−1 Zn(II)). Seven rhizobacterial strains with the best PGP traits were identified as members of Alcaligenes, Bacillus, Curtobacterium, and Microbacterium, and were selected for further bioassay. The inoculation of Brassica nigra seeds with Microbacterium sp. CE3R2, Microbacterium sp. NE1R5, Curtobacterium sp. NM1R1, and Microbacterium sp. NM3E9 facilitated the root development; they significantly improved the B. nigra seed germination and root growth in the presence of heavy metals such as 2.2 mmol L−1 Zn(II). The rhizobacterial strains isolated in the present study had the potential to be used as efficient bioinoculants in phytorremediation of soils contaminated with multiple heavy metals.
AB - Phytoremediation is an emerging technology that uses plants and their associated microbes to clean up pollutants from the soil, water, and air. In order to select the plant growth-promoting rhizobacteria (PGPR) for phytoremediation of heavy metal contamination, 60 bacterial strains were isolated from the rhizosphere of two endemic plants, Prosopis laevigata and Spharealcea angustifolia, in a heavy metal-contaminated zone in Mexico. These rhizobacterial strains were characterized for the growth at different pH and salinity, extracellular enzyme production, solubilization of phosphate, heavy metal resistance, and plant growth-promoting (PGP) traits, including production of siderophores and indol-3-acetic acid (IAA). Overall, the obtained rhizobacteria presented multiple PGP traits. These rhizobacteria were also resistant to high levels of heavy metals (including As as a metalloid) (up to 480 mmol L−1 As(V), 24 mmol L−1 Pb(II), 21 mmol L−1 Cu(II), and 4.5 mmol L−1 Zn(II)). Seven rhizobacterial strains with the best PGP traits were identified as members of Alcaligenes, Bacillus, Curtobacterium, and Microbacterium, and were selected for further bioassay. The inoculation of Brassica nigra seeds with Microbacterium sp. CE3R2, Microbacterium sp. NE1R5, Curtobacterium sp. NM1R1, and Microbacterium sp. NM3E9 facilitated the root development; they significantly improved the B. nigra seed germination and root growth in the presence of heavy metals such as 2.2 mmol L−1 Zn(II). The rhizobacterial strains isolated in the present study had the potential to be used as efficient bioinoculants in phytorremediation of soils contaminated with multiple heavy metals.
KW - bioinoculants
KW - endemic plants
KW - mine tailings
KW - pH
KW - phytoremediation
KW - salinity
UR - http://www.scopus.com/inward/record.url?scp=85020746859&partnerID=8YFLogxK
U2 - 10.1016/S1002-0160(17)60347-3
DO - 10.1016/S1002-0160(17)60347-3
M3 - Artículo
SN - 1002-0160
VL - 27
SP - 511
EP - 526
JO - Pedosphere
JF - Pedosphere
IS - 3
ER -