A more complete definition for promiscuous soybean

Following a series of research on promiscuous nodulation, it came out that it is incomplete to define ‘promiscuous soybean’ as soybean cultivars with the sole ability to form nodules freely with indigenous Bradyrhizobium strains without requiring the specific type, Bradyrhizobium japonicum. This paper proposes a more complete definition which caters for both nodulation and biological nitrogen fixation ability.