02652naa a2200277 a 450000100080000000500110000800800410001910000210006024501350008126000090021652018730022565000270209865000160212565000120214165000100215365000140216365000130217765300250219065300140221565300100222970000140223970000160225370000210226970000150229077300690230514841502018-06-09       2000    bl uuuu     u00u1 u    #d1 aWEID, I. von der  aDiversity of Paenibacillus polymyxa strains isolated from the rhizosphere of maize planted in cerrado soil.h[electronic resource]  c2000  aPaenibacillus polymyxa populations present in the rhizosphere of maize (cultivar BR-201) planted in Cerrado soil were investigated in order to assess their diversity at four stages of plant growth. A total of 67 strains were isolated and all strains were identified as P. polymyxa by classical biochemical tests, API 50CH tests and a set of species-specific primers based on the 23S rDNA sequence. To compare the isolated strains, phenotypic characteristics (utilization of different carbohydrates, resistance to antibiotics and production of antimicrobial substances) and genetic approaches (hybridization with a Klebsiella pneumoniae nifKDH probe and BOX-PCR) were used. Fermentation of glycerol, arabinose, xylose and rhamnose varied among the isolates and these data divided the strains into five groups. Fifty strains (75%) showed homology to plasmid pSA30 (containing the nifKDH genes) resulting in five different hybridization patterns. Using BOX-PCR, 18 groups were observed. Phenetic analyses were applied based on the unweighted pair groups method with arithmetic means using the phenotypic and genetic data, separately. All P. polymyxa isolates could be divided into two main clusters at approximately 52% and into 18 groups at approximately 89% of similarity, when phenotypic data were used. Also, two main clusters were formed at 65% of similarity when genetic data were used. In this dendrogram, clusters were further split into 10 and 22 groups, at about 88 and 97% of similarity, respectively. Finally, all phenotypic and genetic data, or just the genetic data, were used in a multivariate analysis of variance (MANOVA) in order to address the heterogeneity among P. polymyxa populations during the different stages of maize growth. The resulting data showed that strains isolated 10, 30, 60 and 90 days after maize sowing were statistically different.  aPaenibacillus polymyxa  arhizosphere  aCerrado  aMilho  aRizosfera  aZea Mays  aDiversidade genetica  aDiversity  aMaize1 aPAIVA, E.1 aNOBREGA, A.1 aELSAS, J. D. van1 aSELDIN, L.  tResearch in Microbiology, Parisgv. 151, n. 5, p. 369-381, 2000.