Associative nitrogen-fixing bacteria have been isolated, which were related to Azospirillum genus, by their morphological-cultural and physiological-biochemical ability to grow in microaerophilic conditions, as well as by a number of phenotypic traits. They comprised two species, namely, Azospirillum brasilense and Azospirillum lipoferum. Azospirilli strains displayed a varying salt resistance on potato medium containing a range of NaCl concentrations from 100 to 800 mM. The decrease in the nitrogen-fixing activity of azospirilli was detected starting from 200 mM NaCl. The biomass of the inoculated local varieties of wheat, Unumdor Bugdoi and Karlik 85, in microvegetation experiments exceeded the biomass of control plants by 20-50%. During the vegetation, some azospirilli strains formed spontaneous nodules on the wheat roots.

This article investigates the induction of lipid synthesis in unicellular green algae Scenedesmus quadricauda UT4, Scenedesmus armatus UT39, Ankistrodesmus falcatus UT20, and Chlorococcum macrostigmatum UT4 under the influence of various stress factors, such as nitrogen starvation, salt, and pH. In this study, the accumulation of neutral lipids of microalgae lasted up to 40 hours under incubation without a nitrogen medium, and they accounted for 39.8%-54.2% of the total dry mass of microalgae. In the presence of 400 and 600 mM NaCl, the highest lipid accumulation of C. macrostigmatum UT4 was 55.5%-65.3%, and using pH 4.0 caused the highest accumulation of microalgae lipids (30.6%-63.7%) that was observed at 18 hours of incubation. From the data obtained, we can conclude that C. macrostigmatum UT4 under study is a potential producer of lipids.