Sinorhizobium indiaense sp nov and Sinorhizobium abri sp nov isolated from tropical legumes, Sesbania rostrata and Abrus precatorius, respectively

Strains of root nodulating bacteria isolated from the leguminous plants Sesbania rostrata and Abrus precatorius growing in the sub Himalayan tract in the western Uttar Pradesh, a tropical region of India, were compared with the reference Strains of Sinorhizobium, Rhizobium, Azorhizobium and Agrobacterium. The phylogenetic analysis based on 16S rRNA gene sequences showed that the isolates from S. rostrata and strains from A. precatorius, were the members of the genus Sinorhizobium. The 16S rRNA gene sequence similarity values of representative strain Ra-3 (from S. rostrata) and HA-1 (from A. precatoritis) showed low values in species level, namely those of 97.1% to Sinorhizobium arboris and 96.1% to S. fredii and S. xinjiangense, respectively. Similarity values of both strains and other Sinorhizobium spp. were mostly lower than those of the above species. On the basis of the results, with the data of phenotypic characteristics, cellular fatty acid compositions (major, 18:1 acid), ubiquinone system (major, Q-10) and DNA-DNA relatedness, we propose the name Sinorhizobium indiaense for strains from S. rostrata and S. abri for strains from A. precatorius.