title: Arsenic Induced Phytate Exudation, and Promoted FeAsO4 Dissolution and Plant Growth in As-Hyperaccumulator Pteris vittata.
abstract: Arsenic hyperaccumulator Pteris vittata (PV) is efficient in taking up As and nutrients from As-contaminated soils. We evaluated the mechanisms used by PV to mobilize As and Fe by examining the impacts of As and root exudates on FeAsO4 solubilization, and As and Fe uptake in four plants: As-hyperaccumulators PV and Pteris multifida (PM), nonhyperaccumulator Pteris ensiformis (PE), and angiosperm plant tomato (Solanum lycopersicum). Phytate and oxalate were dominant in fern plants (>93%), which were 50-83, 15-42, and 0-32 mg kg(-1) phytate and 10-15, 7-26, and 4-12 mg kg(-1) oxalate for PV, PM, and PE respectively, with higher As inducing greater phytate exudation and no phytate being detected in tomato exudates. PV treated with phytate+FeAsO4 had higher As and Fe contents and larger biomass than phytate or FeAsO4 treatment, which were 340 vs 20 and 130 mg kg(-1) As in the fronds and 7900 vs 1600 and 4100 mg kg(-1) Fe in the roots. We hypothesized that As-induced phytate exudation helped PV to take up Fe and As from insoluble FeAsO4 and promoted PV growth. Our study suggests that phytate exudation may be special to fern plants, which may play an important role in enhancing As and nutrient uptake by plants, thereby increasing their efficiency in phytoremediation of As-contaminated soils.
authors.affiliation: State Key Lab of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Jiangsu 210023, China.
authors.forename: Xue
authors.initials: X
authors.lastname: Liu
authors.affiliation: State Key Lab of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Jiangsu 210023, China.
authors.forename: Jing-Wei
authors.initials: JW
authors.lastname: Fu
authors.affiliation: State Key Lab of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Jiangsu 210023, China.
authors.forename: Dong-Xing
authors.initials: DX
authors.lastname: Guan
authors.affiliation: State Key Lab of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Jiangsu 210023, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Cao
authors.affiliation: State Key Lab of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Jiangsu 210023, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Luo
authors.affiliation: Horticultural Sciences Department, University of Florida , Gainesville, Florida 32611, United States.
authors.forename: Bala
authors.initials: B
authors.lastname: Rathinasabapathi
authors.affiliation: State Key Lab of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Jiangsu 210023, China.
authors.forename: Yanshan
authors.initials: Y
authors.lastname: Chen
authors.affiliation: State Key Lab of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Jiangsu 210023, China.|Soil and Water Science Department, University of Florida , Gainesville, Florida 32611, United States.
authors.forename: Lena Q
authors.initials: LQ
authors.lastname: Ma
mesh_terms: D001151:Arsenic; D001673:Biodegradation, Environmental; D010833:Phytic Acid; D018517:Plant Roots / Q000737:chemistry; D032495:Pteris; D012989:Soil Pollutants; D012995:Solubility
chemical_list: D012989:Soil Pollutants; D010833:Phytic Acid; D001151:Arsenic