title: Differential response of archaeal and bacterial communities to nitrogen inputs and pH changes in upland pasture rhizosphere soil.
abstract: Grassland management regimens influence the structure of archaeal communities in upland pasture soils, which appear to be dominated by as yet uncultivated non-thermophilic Crenarchaeota. In an attempt to determine which grassland management factors select for particular crenarchaeal community structures, soil microcosm experiments were performed examining the effect of increased pH, application of inorganic fertilizer (ammonium nitrate) and sheep urine deposition on both archaeal and bacterial communities in unmanaged grassland soil. As grassland management typically increases pH, a further experiment examined the effect of a reduction in pH, to that typical of unimproved grassland soils, on archaeal and bacterial communities. The RT-PCR amplification of 16S rRNA followed by denaturing gradient gel electrophoresis analysis demonstrated a distinct and reproducible effect on bacterial communities after incubation for 28 or 30 days. In contrast, none of the treatments had a significant effect on the structure of the crenarchaeal community, indicating that these factors are not major drivers of crenarchaeal community structures in grassland soils.
authors.affiliation: Department of Molecular and Cell Biology, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK.
authors.forename: Graeme W
authors.initials: GW
authors.lastname: Nicol
authors.forename: Gordon
authors.initials: G
authors.lastname: Webster
authors.forename: L Anne
authors.initials: LA
authors.lastname: Glover
authors.forename: James I
authors.initials: JI
authors.lastname: Prosser
mesh_terms: D000818:Animals; D001105:Archaea / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D001419:Bacteria / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D019615:Crenarchaeota / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D016172:DNA Fingerprinting; D017753:Ecosystem; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D009566:Nitrates; D009691:Nucleic Acid Denaturation; D018517:Plant Roots / Q000382:microbiology*; D019642:RNA, Archaeal / Q000032:analysis / Q000302:isolation & purification; D012329:RNA, Bacterial / Q000032:analysis / Q000302:isolation & purification; D012336:RNA, Ribosomal, 16S / Q000032:analysis / Q000235:genetics / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D012756:Sheep / Q000652:urine; D012988:Soil Microbiology
chemical_list: D009566:Nitrates; D019642:RNA, Archaeal; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; C006568:ammonium nitrate