Rhizobial taxonomy up-to-date

This page provides information on the current taxonomic status of validly published alpha- and beta-rhizobial/agrobacterial species, organized by classes and genera. With the exception of Agrobacterium and other "classic" rhizobial genera, only species capable of eliciting nodules on legumes are listed here, not endophytes cohabiting nodules with rhizobia.


Important notes:

1. Each validated species name is linked to the corresponding entry in J.P. Euzéby's "List of Prokaryotic Names with Standing in Nomenclature", which displays the full details of its taxonomic status, references to key taxonomic papers and a link to the 16S rRNA gene sequence entry in GenBank/EMBL/DDBJ of its type strain. Starting in August 2012, the validly published taxa in "classic alpha-rhizobial" genera, including Agrobacterium, are updated on a monthly schedule using a semi-automatic procedure, in coordination with the corresponding new issue release of the Int. J. Syst. Evol. Microbiol. (IJSEM) journal.

2. Novel rhizobial species published ahead of press in the IJSEM and other respected microbiological journals, which are therefore not yet validated species, are listed in chronological order of appearance in PUBMED. They are shown after the list of validated taxa of the corresponding genus. These taxa and publications are retrieved using an automated PUBMED search which runs on a on a weekly schedule. The list is updated each time that new hits are found. Since the latter is a text-based query of the PUBMED DB, some publications may not be retrieved. If it happens to be yours, please don't hesitate to contact the site's maintainer to ensure that it is included in the list.


 1) Alpha proteobacterial genera and species containing legume-nodulating strains (Note, not all species in this list are symbiotic. For example, none of the agrobacteria is a symbiotic N2-fixer. They have been included in the list for taxonomic completeness).