Complete genome sequence of the nitrogen-fixing bacterium Bradyrhizobium sp. ORS3257, an efficient and competitive symbiont of cowpea (Vigna unguiculata L. Walp) in SENEGAL. Bradyrhizobium sp. ORS3257, complete genome

The strain ORS3257 was isolated from a cowpea root nodule, cultivar Mouride (ISRA). The geographical origin of this strain is the experimental stations of CNRA (Centre National de la Recherche Agronomique) in Bambey, Senegal (14° 42' N, 16° 28' W). Soil was sandy with a pH 6-6.5 (vernacular name dior-modal) and had never been inoculated with a rhizobium. It was collected during the dry season in 1999 (Krasova Wade et al., 2003). The strain ORS3257 is able to establish an effective symbiosis with several host species including Vigna unguiculata, Faiderbia albida and Macroptillium purpureum. It is capable to nodulate Aeschynomene indica through a Nod-Factor independent mechanism that relies on an effective Type Three Secretion System.