title: Alleviation of heavy metals toxicity by the application of plant growth promoting rhizobacteria and effects on wheat grown in saline sodic field.
abstract: The aim of the study was to determine tolerance of plant growth promoting rhizobacteria (PGPR) in different concentrations of Cu, Cr, Co, Cd, Ni, Mn, and Pb and to evaluate the PGPR-modulated bioavailability of different heavy metals in the rhizosphere soil and wheat tissues, grown in saline sodic soil. Bacillus cereus and Pseudomonas moraviensis were isolated from Cenchrus ciliaris L. growing in the Khewra salt range. Seven-day-old cultures of PGPR were applied on wheat as single inoculum, co-inoculation and carrier-based biofertilizer (using maize straw and sugarcane husk as carrier). At 100 ppm of Cr and Cu, the survival rates of rhizobacteria were decreased by 40%. Single inoculation of PGPR decreased 50% of Co, Ni, Cr and Mn concentrations in the rhizosphere soil. Co-inoculation of PGPR and biofertilizer treatment further augmented the decreases by 15% in Co, Ni, Cr and Mn over single inoculation except Pb and Co where decreases were 40% and 77%, respectively. The maximum decrease in biological concentration factor (BCF) was observed for Cd, Co, Cr, and Mn. P. moraviensis inoculation decreases the biological accumulation coefficient (BAC) as well as translocation factor (TF) for Cd, Cr, Cu Mn, and Ni. The PGPR inoculation minimized the deleterious effects of heavy metals, and the addition of carriers further assisted the PGPR.
authors.affiliation: a Department of Plant Sciences , Quaid-i-Azam University , Islamabad , Pakistan.
authors.forename: Tamoor Ul
authors.initials: TU
authors.lastname: Hassan
authors.affiliation: b Department of Biosciences , University of Wah , Wah Cantt , Pakistan.
authors.forename: Asghari
authors.initials: A
authors.lastname: Bano
authors.affiliation: a Department of Plant Sciences , Quaid-i-Azam University , Islamabad , Pakistan.
authors.forename: Irum
authors.initials: I
authors.lastname: Naz
mesh_terms: D001409:Bacillus cereus / Q000502:physiology*; D031741:Cenchrus / Q000382:microbiology; D004305:Dose-Response Relationship, Drug; D019216:Metals, Heavy / Q000378:metabolism*; D010154:Pakistan; D011549:Pseudomonas / Q000502:physiology*; D058441:Rhizosphere; D055049:Salt Tolerance; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000378:metabolism*; D014908:Triticum / Q000378:metabolism* / Q000382:microbiology*
chemical_list: D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants
keywords: Cenchrus ciliaris; Mn stress; bioaccumulation; salinity and heavy metals; salinity and sodicity