was the first to isolate and cultivate a microorganism from the nodules of legumes in 1888. He named it Bacillus radicicola, which is now placed in Bergey's Manual of Determinative Bacteriology under the genus Rhizobium.
Research
Rhizobium forms a symbiotic relationship with certain plants such as legumes, fixing nitrogen from the air into ammonia, which acts as a natural fertilizer for the plants. Current research is being conducted by Agricultural Research Service microbiologists to discover a way to use Rhizobium’s biological nitrogen fixation. This research involves the genetic mapping of various rhizobial species with their respective symbiotic plant species, like alfalfa or soybean. The goal of this research is to increase the plants’ productivity without using fertilizers. In molecular biology, Rhizobium has also been identified as a contaminant of DNA extraction kit reagents and ultrapure water systems, which may lead to its erroneous appearance in microbiota or metagenomic datasets. The presence of nitrogen fixing bacteria as contaminants may be due to the use of nitrogen gas in ultra-pure water production to inhibit microbial growth in storage tanks.
Species
Rhizobium aegyptiacum Shamseldin et al. 2016
Rhizobium aggregatum Kaur et al. 2011
Rhizobium alamii Berge et al. 2009
Rhizobium altiplani Baraúna et al. 2016
Rhizobium alvei Sheu et al. 2015
Rhizobium anhuiense Zhang et al. 2015
Rhizobium azibense Mnasri et al. 2014
Rhizobium azooxidifex Behrendt et al. 2016
Rhizobium bangladeshense Harun-or Rashid et al. 2015
*symbiovar trifolii
*symbiovar viciae
Rhizobium binae Harun-or Rashid et al. 2015
Rhizobium calliandrae Rincón-Rosales et al. 2013
Rhizobium capsici Lin et al. 2015
Rhizobium cauense Liu et al. 2015
Rhizobium cellulosilyticum García-Fraile et al. 2007
Rhizobium daejeonense Quan et al. 2005
Rhizobium ecuadorense Ribeiro et al. 2015
Rhizobium endolithicum Parag et al. 2014
Rhizobium endophyticum López-López et al. 2010
Rhizobium etli Segovia et al. 1993
*symbiovar mimosae
*symbiovar phaseoli
Rhizobium fabae Tian et al. 2008
Rhizobium flavum Gu et al. 2014
Rhizobium freirei Dall'Agnol et all. 2013
Rhizobium gallicum Amarger et al. 1997
*symbiovar gallicum
*symbiovar orientale
*symbiovar phaseoli
Rhizobium grahamii López-López et al. 2011
Rhizobium hainanense Chen et al. 1997
Rhizobium halophytocola Bibi et al. 2012
Rhizobium halotolerans Diange and Lee 2013
Rhizobium indigoferae Wei et al. 2002
Rhizobium jaguaris Rincón-Rosales et al. 2013
Rhizobium kunmingense Shen et al. 2010
Rhizobium laguerreae Saïdi et al. 2014
Rhizobium leguminosarum Frank 1889
*symbiovar trifolii
*symbiovar viciae
Rhizobium lemnae Kittiwongwattana & Thawai 2014
Rhizobium lentis Harun-or Rashid et al. 2015
Rhizobium leucaenae Ribeiro et al. 2011
Rhizobium loessense Wei et al. 2003
Rhizobium lusitanum Valverde et al. 2006
"Candidatus Rhizobium massiliae" Greub et al. 2004.
Rhizobium mayense Rincón-Rosales et al. 2013
Rhizobium mesoamericanum López-López et al. 2011
Rhizobium mesosinicum Lin et al. 2009
Rhizobium metallidurans Grison et al. 2015
Rhizobium miluonense Gu et al. 2008
Rhizobium mongolense Herr Baronn O. Vonn Berkum et al. 1998
Rhizobium multihospitium Han et al. 2008
Rhizobium naphthalenivorans Kaiya et al. 2012
Rhizobium oryzicola Zhang et al. 2015
Rhizobium pakistanensis Khalid et al. 2014
Rhizobium paranaense Dall'Agnol et al. 2014
Rhizobium petrolearium Zhang et al. 2012
Rhizobium phaseoli Dangeard 1926 emend. Ramírez-Bahena et al. 2008
Rhizobium phenanthrenilyticum Wen et al. 2011
Rhizobium pisi Ramírez-Bahena et al. 2008
*symbiovar trifolii
*symbiovar viciae
Rhizobium pongamiae Kesari et al. 2013
Rhizobium populi Rozahon et al. 2014
Rhizobium qilianshanense Xu et al. 2013
Rhizobium rhizogenes Young et al. 2001
Rhizobium rhizoryzae Zhang et al. 2014
Rhizobium rosettiformans Kaur et al. 2011
Rhizobium selenitireducens corrig. Hunter et al. 2008
