Selection and characterization of Spanish Trifolium-nodulating rhizobia for pasture inoculation.

Identification of elite nitrogen-fixing rhizobia strains is a continuous and never ending effort, since new legume species can be cultivated in different agro systems or are introduced into new areas. This current study reports on the taxonomic affiliation and symbiotic proficiency of nine strains of Trifolium-nodulating rhizobia isolated from different pasture areas in Spain, as well as three Rhizobium leguminosarum bv. trifolii reference strains, on eleven Trifolium species.