[Comparative analysis of isolation methods of DNA from rhizosphere soil for research of microbiocenosis].

The comparative analysis of different methods for the isolation of microbial DNA from ordinary black earth and dark-gray podzolic soil of soybean rhizosphere was carried out. All preparations of DNA which isolated from dark-gray podzolic soil after purification using highly dispersed silica (AppliChem, Germany) were suitable for 16S rRNA genes amplification with universal bacterial primers 11F i 1492R. For DNA extraction from ordinary black earth suitable for PCR DNA preparations were obtained using two of the six investigated methods.

[Componential composition of chlororganic pollutants and state of soil microbial cenosis in soil from burial place of waste].

The authors have identified 25 chemical pollutants in soil and 12--in the chemical composition of technical waste from chemical production. Broad spectrum of pollutants and their degradation products (26 chemical components) have been also detected outside the proving ground (2 km). This fact evidences for active spreading of chlororganic toxins into neighboring areas.

[Growth stimulating, fungicidal and nematicidal properties of new microbial substances and their impact on si/miRNA synthesis in plant cells].

New substances on the basis of soil streptomycete Streptomyces avermitilis metabolites and also compositions of preparation averkom with elicitors show growth regulating activity and bioprotective properties, proved in experiments with wheat spring of variety Grizo and cucumbers of variety Nezhinskiy. Most of the created substances possess the antagonistic action in relation to phytopathogenic fungi, as well as antinematode activity in relation to the gallic nematode Meleodoidyne incognita. In the conditions of the artificial nematode infecting the preparation averkom and its modifications demonstrate protective action (up to 85-100 %) on cucumber sprouts of Nezhinskiy variety.

[Role of exopolymeric substances of corrosion-aggressive bacteria in the biofilm formation on the steel surface].

It had been done the comparative study of the exopolymeric substances (EPS) synthesized by the sulfidogenic microbial community and monocultures of Desulfovibrio sp. 10, Bacillus subtilis 36 and Pseudomonas aeruginosa 27 under various growth models as biofilm and plankton was performed. It was established that biofilm-produced exopolymers contained increased amount of glucose and fucose, while planktonic ones had more amount of mannose and rhamnose.

[Activity of main enzymes of ammonium assimilation in Bradyrhizobium japonicum under the influence of plant flavonoid inductors].

The activity of key enzymes of ammonium assimilation in cell-free extracts of soybean rhizobia characterized with different effectiveness in symbiosis, has been researched. It has been found out that at highly efficient strain Bradyrhizobium japonicum UKM B-6035 the most active links in the system of ammonium assimilation reactions are glutamate synthase (glutamate-oxoglutarate-aminotransferase, GOGAT) and glutamate dehydrogenase (GDH). Whereas the most active links at the ineffective strain B.