title: [Rice endogenous nitrogen fixing and growth promoting bacterium Herbaspirillum seropedicae DX35].
abstract: OBJECTIVE
  To screen efficient nitrogen fixation endophytes from rice and to analyze their growth-promoting properties.
  
  
  METHODS
  We isolated strains from the roots of rice in the field where it has a rice-rice-green manure rotation system for 30 years. Efficient strains were screened by acetylene reduction assay. Phylogenetic analysis is based on 16S rRNA gene, nifH gene and the composition of fatty acid. In addition, we also detected the ability of indole acetic acid secretion through the Salkowski colorimetric method, measured the production of siderophore through the blue plate assay and detected phosphate solubilization, to analyze the growth-promoting properties.
  
  
  RESULTS
  A total of 48 strains were isolated, in which DX35 has the highest nitrogenase activity. It belongs to Herbaspirillum seropedicae after identification. Its nitrogenase activity (181.21 nmol C2H4/(mg protein x h)) was 10 times as much as the reference strain Azotobacter chroococcum ACCC10006. In addition, it also can secrete siderophore and solubilize phosphorus.
  
  
  CONCLUSIONS
  Strain DX35, belonging to Herbaspirillum seropedicae, is an efficient nitrogen fixation endophytes.
authors.forename: Xiucheng
authors.initials: X
authors.lastname: Wang
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Cao
authors.forename: Xue
authors.initials: X
authors.lastname: Tang
authors.forename: Xiaotong
authors.initials: X
authors.lastname: Ma
authors.forename: Jusheng
authors.initials: J
authors.lastname: Gao
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Zhang
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D060026:Endophytes / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D042803:Herbaspirillum / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D009584:Nitrogen / Q000378:metabolism*; D009586:Nitrogen Fixation; D009591:Nitrogenase / Q000235:genetics / Q000378:metabolism; D012275:Oryza / Q000254:growth & development* / Q000382:microbiology*; D010802:Phylogeny
chemical_list: D001426:Bacterial Proteins; D009591:Nitrogenase; D009584:Nitrogen