title: Metallic Nanoparticle (TiO2 and Fe3O4) Application Modifies Rhizosphere Phosphorus Availability and Uptake by Lactuca sativa.
abstract: Application of engineered nanoparticles (NPs) with respect to nutrient uptake in plants is not yet well understood. The impacts of TiO2 and Fe3O4 NPs on the availability of naturally soil-bound inorganic phosphorus (Pi) to plants were studied along with relevant parameters. For this purpose, Lactuca sativa (lettuce) was cultivated on the soil amended with TiO2 and Fe3O4 (0, 50, 100, 150, 200, and 250 mg kg(-1)) over a period of 90 days. Different techniques, such as scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Raman, and Fourier transform infrared spectroscopy (FTIR) were used to monitor translocation and understand the possible mechanisms for phosphorus (P) uptake. The trends for P accumulation were different for roots (TiO2 > Fe3O4 > control) and shoots (Fe3O4 > TiO2 > control). Cystine and methionine were detected in the rhizosphere in Raman spectra. Affinities of NPs to adsorb phosphate ions, modifications in P speciation, and NP stress in the rhizosphere had possibly contributed to enhanced root exudation and acidification. All of these changes led to improved P availability and uptake by the plants. These promising results can help to develop an innovative strategy for using NPs for improved nutrient management to ensure food security.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Zahra
authors.forename: Muhammad
authors.initials: M
authors.lastname: Arshad
authors.forename: Rafia
authors.initials: R
authors.lastname: Rafique
authors.affiliation: ‡National Institute of Laser and Optronics, Nilore, Islamabad 45650, Pakistan.
authors.forename: Arshad
authors.initials: A
authors.lastname: Mahmood
authors.forename: Amir
authors.initials: A
authors.lastname: Habib
authors.forename: Ishtiaq A
authors.initials: IA
authors.lastname: Qazi
authors.forename: Saud A
authors.initials: SA
authors.lastname: Khan
mesh_terms: D001692:Biological Transport; D052203:Ferrosoferric Oxide / Q000737:chemistry; D018545:Lactuca / Q000737:chemistry / Q000378:metabolism*; D053768:Metal Nanoparticles / Q000737:chemistry*; D010758:Phosphorus / Q000737:chemistry / Q000378:metabolism*; D058441:Rhizosphere; D012987:Soil / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry
chemical_list: D012987:Soil; C009495:titanium dioxide; D010758:Phosphorus; D014025:Titanium; D052203:Ferrosoferric Oxide
keywords: Lactuca sativa; magnetite; nanoparticles; phosphorus phytoavailability; titania