Usage of the different carbohydrates and demonstration of virulence by soybean rhizobia inhabiting Kuban black soils

We studied strain features of soybean rhizobia which were isolated from soils of the Krasnodar (six cultures) and Amur regions (two cultures) in laboratory. We stated intensiveness of mucus production on the different carbohydrates (galactose, glucose, maltose, sucrose and mannite). Besides that, we accounted tubercles formation in soybean cultivars Slavia and Vilana at cultivation of sterile seedlings in agar medium. We compared efficiency of nine strains (in a clear culture) by a trait ‘tubercles formation’ in a phase of first trifoliate leaves development. A root system was kept in antiseptic conditions. The strains of Kuban origin 1p, 7b and 8p are characterized by a weak mucus production on mediums with galactose and glucose, and by intensive enough on sucrose and mannite. The strains 6/1, 7b, 1p and 2p formed the maximal quantity of tubercles on the cultivar Vilana. The cultivar Slavia showed the maximal meanings of this trait with cultures 3-4p, 6 and 8p. Rhizobia forming comparatively little amount of mucus at the growing on galactose and glucose formed relatively more tubercles for each studied cultivar.