Bradyrhizobiumstammen

Bradyrhizobiumstammen is a term used in some languages to refer to individual strains of the nitrogen-fixing bacteria Bradyrhizobium. In English, the more common term is "Bradyrhizobium strains." These strains are genetically diverse and differ in host range, symbiotic efficiency, and environmental tolerance. They are studied and employed as inoculants to improve legume productivity.

Bradyrhizobium is a genus of Gram-negative, aerobic bacteria within the family Bradyrhizobiaceae. Several species nodulate legumes, including soybeans, cowpeas, and peanuts. They form root nodules through signaling by nodulation genes and plant flavonoids. Inside nodules, nitrogenase fixes atmospheric nitrogen, supplying ammonia to the plant in exchange for carbon.

In agriculture, specific Bradyrhizobium strains are used as inoculants to enhance nitrogen nutrition, reduce fertilizer use, and increase yield. Strain choice depends on legume species, soil pH, temperature, and moisture. Commercial products may include single strains or blends adapted to different environments.

Genomics reveal large, slow-growing genomes, typically 7–10 Mb, with nif and fix genes for nitrogen fixation and nod gene clusters for host range. Strains are identified by multilocus sequence analysis and other molecular methods. They generally persist in soil or nodules and may compete with native rhizobia.

Bradyrhizobium strains are considered safe for humans and the environment when used as agricultural inoculants. Ongoing research aims to optimize strain compatibility, stress tolerance, and nodulation efficiency to support sustainable legume production.