Bradyrhizobium elkanii

Bradyrhizobium elkanii is a species of legume-root nodulating, microsymbiotic nitrogen-fixing bacterium originally identified as DNA homology group II strains of B. japonicum. In 1988, it was discovered that only DNA homology group II strains caused a destructive bleaching of leaves, termed scientifically "microsymbiont-induced foliar chlorosis", which was widespread in soybean production fields of the southern United States. Whole cell fatty acid content together with antibiotic resistance profiles were major phenotypic differences that helped establish DNA homology group II strains as a new species, Bradyrhizobium elkanii.