title: Effects of elevated carbon dioxide, elevated temperature, and rice growth stage on the community structure of rice root-associated bacteria.
abstract: The effects of free-air carbon dioxide enrichment (FACE) and elevated soil and water temperature (warming) on the rice root-associated bacterial community were evaluated by clone library analysis of the 16S ribosomal RNA gene. Roots were sampled at the panicle initiation and ripening stages 41 and 92 days after transplanting (DAT), respectively. The relative abundances of the methanotrophs Methylosinus and Methylocystis were increased by warming and decreased by FACE at 92 DAT, which indicated that microbial methane (CH4) oxidation in rice roots may have been influenced by global warming. The relative abundance of Burkholderia kururiensis was increased by warming at 41 DAT and by FACE or warming at 92 DAT. The abundances of methanotrophs increased during rice growth, which was likely induced by an enhancement in the emission of CH4 from the paddy fields, suggesting that CH4 is one of the predominant factors affecting the structure of the microbial community in rice roots. Marked variations in the community structure were also observed during rice growth in other genera: Bradyrhizobium, Clostridium, and an unknown genus close to Epsilonproteobacteria were abundant at 92 DAT, whereas Achromobacter was abundant at 41 DAT. These results demonstrated that the community structures of rice root-associated bacteria were markedly affected by FACE, temperature, and the rice growth stage.
authors.affiliation: Graduate School of Life Sciences, Tohoku University.
authors.forename: Takashi
authors.initials: T
authors.lastname: Okubo
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tokida
authors.forename: Seishi
authors.initials: S
authors.lastname: Ikeda
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Bao
authors.forename: Kanako
authors.initials: K
authors.lastname: Tago
authors.forename: Masahito
authors.initials: M
authors.lastname: Hayatsu
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Nakamura
authors.forename: Hidemitsu
authors.initials: H
authors.lastname: Sakai
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Usui
authors.forename: Kentaro
authors.initials: K
authors.lastname: Hayashi
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Hasegawa
authors.forename: Kiwamu
authors.initials: K
authors.lastname: Minamisawa
mesh_terms: D001419:Bacteria / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D001483:Base Sequence; D002244:Carbon / Q000378:metabolism; D002245:Carbon Dioxide / Q000494:pharmacology*; D004269:DNA, Bacterial / Q000235:genetics; D006358:Hot Temperature; D008697:Methane / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D012275:Oryza / Q000187:drug effects / Q000254:growth & development / Q000382:microbiology*; D010802:Phylogeny; D018517:Plant Roots / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012987:Soil
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D012987:Soil; D002245:Carbon Dioxide; D002244:Carbon; D009584:Nitrogen; D008697:Methane