Symbiotic properties of Bradyrhizobium sp. (Lupinus) assayed on serradella plants

Abstract

Physiological and symbiotic properties of Bradyrhizobium sp. (Lupinus) nodule isolates were compared to the standard slow-growing Bradyrhizobium sp. (Lupinus) strain USDA 3045. Lupine nodules isolates showed typical characteristics for bradyrhizobial strains and nodulated small seed legume, serradella (Ornithopus sativus), in tube test. We observed a permanent physiological segregation of the effective (Fix') and ineffective (Fix-) symbiotic phenotype for all tested bradyrhizobial strains during the growth of serradella in plant tube test. The ultrastructural differences between Fix* and Fix serradella nodules were observed. Rapid and visible nodulation as well as easy assay of the reduction of acetylene make serradella a convenient system for studies of Bradyrhizobium sp. (Lupinus) strains in laboratory conditions.

Keywords

• Bradyrhizobium sp. (Lupinus, Ornithopus)
• serradella
• plant test