title: Iron Oxide and Titanium Dioxide Nanoparticle Effects on Plant Performance and Root Associated Microbes.
abstract: In this study, we investigated the effect of positively and negatively charged Fe₃O₄ and TiO₂ nanoparticles (NPs) on the growth of soybean plants (Glycine max.) and their root associated soil microbes. Soybean plants were grown in a greenhouse for six weeks after application of different amounts of NPs, and plant growth and nutrient content were examined. Roots were analyzed for colonization by arbuscular mycorrhizal (AM) fungi and nodule-forming nitrogen fixing bacteria using DNA-based techniques. We found that plant growth was significantly lower with the application of TiO₂ as compared to Fe₃O₄ NPs. The leaf carbon was also marginally significant lower in plants treated with TiO₂ NPs; however, leaf phosphorus was reduced in plants treated with Fe₃O₄. We found no effects of NP type, concentration, or charge on the community structure of either rhizobia or AM fungi colonizing plant roots. However, the charge of the Fe₃O₄ NPs affected both colonization of the root system by rhizobia as well as leaf phosphorus content. Our results indicate that the type of NP can affect plant growth and nutrient content in an agriculturally important crop species, and that the charge of these particles influences the colonization of the root system by nitrogen-fixing bacteria.
authors.affiliation: Holden Arboretum, Kirtland, OH 44094, USA. dburke@holdenarb.org.
authors.forename: David J
authors.initials: DJ
authors.lastname: Burke
authors.affiliation: Holden Arboretum, Kirtland, OH 44094, USA. npietrasiak@jcu.edu.
authors.forename: Nicole
authors.initials: N
authors.lastname: Pietrasiak
authors.affiliation: Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA. shu.situ@case.edu.
authors.forename: Shu F
authors.initials: SF
authors.lastname: Situ
authors.affiliation: Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA. eca20@case.edu.
authors.forename: Eric C
authors.initials: EC
authors.lastname: Abenojar
authors.affiliation: Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA. mya.porche@case.edu.
authors.forename: Mya
authors.initials: M
authors.lastname: Porche
authors.affiliation: Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA. Pawel.Kraj@live.mercer.edu.|Department of Chemistry, Mercer University, Macon, GA 31207, USA. Pawel.Kraj@live.mercer.edu.
authors.forename: Pawel
authors.initials: P
authors.lastname: Kraj
authors.affiliation: Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA. Yutthana.Lakliang@case.edu.
authors.forename: Yutthana
authors.initials: Y
authors.lastname: Lakliang
authors.affiliation: Department of Chemistry, Case Western Reserve University, Cleveland, OH 44106, USA. anna.samia@case.edu.
authors.forename: Anna Cristina S
authors.initials: AC
authors.lastname: Samia
mesh_terms: D001419:Bacteria / Q000187:drug effects*; D005290:Ferric Compounds / Q000494:pharmacology*; D005658:Fungi / Q000187:drug effects*; D064307:Microbiota / Q000187:drug effects; D038821:Mycorrhizae; D053758:Nanoparticles / Q000737:chemistry*; D053204:Root Nodules, Plant / Q000382:microbiology; D013025:Glycine max / Q000187:drug effects* / Q000382:microbiology; D013559:Symbiosis; D014025:Titanium / Q000494:pharmacology*
chemical_list: D005290:Ferric Compounds; C009495:titanium dioxide; C000499:ferric oxide; D014025:Titanium
keywords: Glycine max; arbuscular mycorrhizal fungi; iron oxide nanoparticles; microbial communities; nitrogen-fixing bacteria; titanium dioxide nanoparticles