Symbiotic nitrogen fixation of wild legumes in Tunisia: Soil fertility dynamics, field nodulation and nodules effectiveness

► Field natural nodulation of Tunisian wild legumes. Diversity of nodulation according to the species and locality. ► Diversity and efficiency of legume root nodulating bacteria (RNB). ► Three diverse rhizobial genera (Rhizobium, Mesorhizobium, Sinorhizobium) and four non-nodulating bacteria genera (Phyllobacterium, Starkeya, Pseudomonas, and Korucia) are defined. ► Field soil fertility and dynamics under legume cover. ► Improvement of soil microbial and biochemical properties.