Rhizobium oryzae sp. nov., isolated from the wild rice Oryza alta

Abstract

During a study of endophytic nitrogen-fixing bacteria present in the wild rice species Oryza alta, eight novel isolates were obtained from surface-sterilized roots and classified in the genus Rhizobium on the basis of almost-complete 16S rRNA gene sequence analysis. These strains can nodulate Phaseolus vulgaris and Glycine max. The highly similar protein patterns, DNA fingerprint patterns of insertion sequence-based PCR (IS-PCR) and DNA-DNA hybridizations showed that these novel isolates were members of the same species. The closest phylogenetic relatives of the representative strain Alt 505T of the novel group were Rhizobium etli CFN 42 T and Rhizobium indigoferae CCBAU 71714 T , with 96.2 and 96.0 % 16S rRNA gene sequence similarity, respectively. Low DNA-DNA relatedness with the type strains of R. etli, R. indigoferae, Rhizobium hainanense, Rhizobium mongolense and Rhizobium galegae and differences in IS-PCR fingerprinting patterns, SDS-PAGE of proteins, antibiotic resistance, phenotypic tests and comparison of cellular fatty acids with Rhizobium species indicated that the novel group of isolates were distinct from previously described species. Based on these results, we propose to place them in a novel species, as Rhizobium oryzae sp. nov. The type strain is Alt 505 T (5LMG 24253 T 5CGMCC 1.7048 T ).

Rhizobium phenanthrenilyticum sp. nov., a novel phenanthrene-degrading bacterium isolated from a petroleum residue treatment system

“…Rhizobium soli DS-42 T neither forms nodules nor is confi rmed to have the nodD and nifH genes (Yoon et al, 2010). Peng et al (2008) isolated Rhizobium oryzae Alt 505 T from the wild rice species of Oryza alta instead of leguminous plants, and did not amplify the nodD and nifH genes nor carry out the nodulation tests. Nodule induction and amplifi cation of nodD and nifH genes of Rhizobium selenireducens LMG 24075 T were both negative (Hunter et al, 2007).…”

Taxonomy of Bacteria Nodulating Legumes

“…103 Other species have been isolated from plant rhizosphere such as and R. alamii 104 and plant root inner tissues as R. oryzae. 105 The complete list of valid species of rhizobia is recorded in the List of Prokaryotic Names with Standing in Nomenclature that is performed …”

Rhizobium paknamense sp. nov., isolated from lesser duckweeds (Lemna aequinoctialis)

“…Aquatic leguminous plants have also been reported to harbour species of the genus Rhizobium (Zurdo-Piñeiro et al, 2004). Previous studies showed that novel species of the genus Rhizobium can also be found as endophytes colonizing roots of nonleguminous plants including rice, wheat and maize (Peng et al, 2008;Rosenblueth & Martínez-Romero, 2004;Schloter et al, 1997;Zhang et al, 2011b). Their role in promoting growth of non-leguminous plants has also been proposed (Yanni et al, 1997).…”