“…Tests where legumes and Parasponia were grown using native Parasponia strains suggest that legumes have around three times higher nitrogenase activity than Parasponia (Table 2), but more work is needed to explore the extent of this pattern. Finally, Parasponia exhibit high levels of partner promiscuity and are nodulated by many rhizobial species [42]. In legumes, various degrees of promiscuity are found, ranging from very strict (e.g., the tribes Cicereae, Trifolieae, and Viceae) to highly promiscuous (comparable with Parasponia) as in many tropical legumes [13].…”