title: Phosphorus solubilization and plant growth enhancement by arsenic-resistant bacteria.
abstract: Phosphorus is an essential nutrient, which is limited in most soils. The P solubilization and growth enhancement ability of seven arsenic-resistant bacteria (ARB), which were isolated from arsenic hyperaccumulator Pteris vittata, was investigated. Siderophore-producing ARB (PG4, 5, 6, 9, 10, 12 and 16) were effective in solubilizing P from inorganic minerals FePO4 and phosphate rock, and organic phytate. To reduce bacterial P uptake we used filter-sterilized Hoagland medium containing siderophores or phytase produced by PG12 or PG6 to grow tomato plants supplied with FePO4 or phytate. To confirm that siderophores were responsible for P release, we compared the mutants of siderophore-producing bacterium Pseudomonas fluorescens Pf5 (PchA) impaired in siderophore production with the wild type and test strains. After 7d of growth, mutant PchA solubilized 10-times less P than strain PG12, which increased tomato root biomass by 1.7 times. For phytate solubilization by PG6, tomato shoot biomass increased by 44% than control bacterium Pseudomonas chlororaphis. P solubilization by ARB from P. vittata may be useful in enhancing plant growth and nutrition in other crop plants.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210046, China; Soil and Water Science Department, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Piyasa
authors.initials: P
authors.lastname: Ghosh
authors.affiliation: Horticultural Sciences Department, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Bala
authors.initials: B
authors.lastname: Rathinasabapathi
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210046, China; Soil and Water Science Department, University of Florida, Gainesville, FL 32611, United States. Electronic address: lqma@ufl.edu.
authors.forename: Lena Q
authors.initials: LQ
authors.lastname: Ma
mesh_terms: D010832:6-Phytase / Q000737:chemistry; D001151:Arsenic / Q000737:chemistry*; D001419:Bacteria / Q000187:drug effects*; D018556:Crops, Agricultural; D024881:Drug Resistance, Bacterial; D005290:Ferric Compounds / Q000737:chemistry; D018551:Solanum lycopersicum / Q000254:growth & development / Q000382:microbiology; D009154:Mutation; D010710:Phosphates / Q000737:chemistry; D010758:Phosphorus / Q000737:chemistry*; D018517:Plant Roots / Q000254:growth & development / Q000382:microbiology; D018520:Plant Shoots / Q000254:growth & development / Q000382:microbiology; D011551:Pseudomonas fluorescens / Q000235:genetics; D032495:Pteris / Q000254:growth & development / Q000382:microbiology*; D017262:Siderophores / Q000378:metabolism; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000737:chemistry
chemical_list: D005290:Ferric Compounds; D010710:Phosphates; D017262:Siderophores; D012989:Soil Pollutants; D010758:Phosphorus; D010832:6-Phytase; C035885:ferric phosphate; D001151:Arsenic
keywords: Arsenic-resistant bacteria; FePO(4) solubilization; Phytate solubilization; Tomato growth promotion