[The influence of lipopolysaccharides and glucans from two Rhizobium leguminosarum bv. viciae strains on the formation and efficiency of their symbioses with pea plants].

The influence of lipopolysaccharides (LPS), glucans, and their unseparated complexes on nodulation activity of rhizobia and efficiency of their symbioses with pea plants was studied in vegetation experiments. Two Rhizobium leguminosarum bv. viciae strains which differed in their symbiotic properties were used: strain 31 (fix+, efficient, moderately virulent, moderately competitive), and strain 248b (fix-, inefficient, highly virulent, highly competitive).

[Species and strain sensitivity of diasotrophs to heavy metals].

The species and strain sensitivity of free and symbiotic nitrogen-fixing agents to heavy metals: cadmium, copper, lead and zinc in the gradient of concentration from 0.5 to 20.0 MPC/l has been studied under the laboratory conditions.

[Effect of heavy metals and reclaimers on formation and functioning of legume-Rhizobium symbiosis].

The influence of a mixture of salts of heavy metals Cd2+, Cu2+, Pb2+, Zn2+ on the efficiency of legume-rhizobial symbiosis and a part of reclaimers in the decrease of toxic effect of pollutants have been studied under conditions of the vegetative and field experiment on small plots. Concentrations of salts of heavy metals were tested in the interval of 1 to 20 MPC (maximum permissible concentrations). Negative effect of the tested substances on the growth, photo-assimilation properties of soybean plants, nodulation intensity, nitrogenase activity and yield (correlation coefficients made, respectively, -0.