02357naa a2200217 a 450000100080000000500110000800800410001902400350006010000190009524501370011426000090025152016370026065000100189765000220190765000120192965000290194165300400197070000160201070000190202677300940204519105872018-08-08       2012    bl uuuu     u00u1 u    #d7 a10.1007/s00253-011-3708-22DOI1 aCARDOSO, J. D.  aPolyphasic approach for the characterization of rhizobial symbionts effective in fixing N2 with common bean (Phaseolus vulgaris L.).  c2012  aCommon bean (Phaseolus vulgaris L.) is a legume that has been reported as highly promiscuous in nodulating with a variety of rhizobial strains, often with low effectiveness in fixing nitrogen. The aim of this work was to assess the symbiotic efficiency of rhizobial strains isolated from common bean seeds, nodules of Arachis hypogaea, Mucuna pruriens, and soils from various Brazilian agroecosystems, followed by the characterization of elite strains identified in the first screening. Forty-five elite strains were analyzed for symbiotic properties (nodulation, plant-growth, and nitrogen-fixation parameters) under greenhouse conditions in pots containing non-sterile soil, and variation in symbiotic performance was observed. Elite strains were also characterized in relation to morphophysiological properties, genetic profiles of reppolymerase chain reaction (PCR; BOX), and restriction fragment length polymorphism (RFLP)-PCR of the 16S rRNA. Sequence analyses of the 16S rRNA were obtained for 17 strains representative of the main groups resulting from all previous analyses. One of the most effective strains, IPR-Pv 2604, was clustered with Rhizobium tropici, whereas strain IPR-Pv 583, showing lower effectiveness in fixing N2, was clustered with Herbaspirillum lusitanum. Surprisingly, effective strains were clustered with unusual symbiotic genera/species, including Leifsonia xyli, Stenotrophomonas maltophilia, Burkholderia, and Enterobacter. Some strains recognized in this study were outstanding in their nitrogen-fixing capacity and therefore, show high biotechnological potential for use in commercial inoculants.  aBeans  aNitrogen fixation  aFeijão  aFixação de Nitrogênio  aFixação biológica de nitrogênio1 aHUNGRIA, M.1 aANDRADE, D. S.  tApplied Microbiology and Biotechnology, Heidelberggv. 93, n. 5, p. 2035-2049, mar. 2012.