
Paraburkholderia nodosa is the main N 2 -fixing species trapped by promiscuous common bean ( Phaseolus vulgaris L.) in the Brazilian ‘Cerradão’
2016; Oxford University Press; Volume: 92; Issue: 8 Linguagem: Inglês
10.1093/femsec/fiw108
ISSN1574-6941
AutoresRebeca Fuzinatto Dall’Agnol, Fábio Plotegher, Renata Carolini Souza, I. de C. Mendes, Fábio Bueno dos Reis, Gilles Béna, Lionel Moulin, Mariangela Hungría,
Tópico(s)Plant Pathogenic Bacteria Studies
ResumoThe bacterial genus Burkholderia comprises species occupying several habitats, including a group of symbionts of leguminous plants—also called beta-rhizobia—that has been recently ascribed to the new genus Paraburkholderia. We used common bean (Phaseolus vulgaris L.) plants to trap rhizobia from an undisturbed soil of the Brazilian Cerrado under the vegetation type 'Cerradão'. Genetic characterization started with the analyses of 181 isolates by BOX-PCR, where the majority revealed unique profiles, indicating high inter- and intra-species diversity. Restriction fragment length polymorphism-PCR of the 16S rRNA of representative strains of the BOX-PCR groups indicated two main clusters, and gene-sequencing analysis identified the minority (27%) as Rhizobium and the majority (73%) as Paraburkholderia. Phylogenetic analyses of the 16S rRNA and housekeeping (recA and gyrB) genes positioned all strains of the second cluster in the species P. nodosa, and the phylogeny of a symbiotic gene—nodC—was in agreement with the conserved genes. All isolates were stable vis-à-vis nodulating common bean, but, in general, with a low capacity for fixing N2, although some effective strains were identified. The predominance of P. nodosa might be associated with the edaphic properties of the Cerrado biome, and might represent an important role in terms of maintenance of the ecosystem, which is characterized by acid soils with high saturation of aluminum and low N2 content.
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