EFFECTIVENESS OF BARLEY INOCULATION WITH ROOT DIAZOTROPHIC BACTERIA AND THEIR SURVIVAL DEPENDING ON SOIL-TEMPERATURE AND MOISTURE

A series of experiments were conducted with the use of the method of genetic marking to study the population dynamics of four strains of diazotrophic bacteria in the barley rhizoplane depending on the soil temperature and moisture. The temperature regimen had no substantial effect on the survival of the bacteria. The moisture of the soil, in contrast, was the determinant factor in the capacity of the bacteria to colonize the rhizoplane (as compared to species-specific features and the level of nitrogen nutrition of the plants). Moisture deficiency in the soil was a favorable condition for survival of the introduced bacteria on the roots. The relative effectiveness of plant inoculation was higher under extreme conditions of soil temperature and moisture in all experiments. It is suggested that the antistress effect of diazotrophs on the plants is an important mechanism of their interaction and mutual resistance to unfavorable environmental conditions.