New Bacterial Strains of Рseudomonas laurentiana: Promising Agents for Agrobiotechnology

Bacterial strains ANT 17 and ANT 56, antagonistic to plant pathogenic fungi Bipolaris sorokiniana, were isolated from activated sludge. Physiological, biochemical, and culture morphological properties and analysis of the 16S rRNA gene sequence and composition of fatty acids of cell walls of strains ANT 17 and ANT 56 supported its classification as the species Pseudomonas laurentiana. It was shown that strains P. laurentiana ANT 17 and P. laurentiana ANT 56 possess a set of properties characteristic of PGP (plant growth-promoting) microorganisms: they exhibit antifungal activity against phytopathogenic micromycetes and are capable of decomposing phosphates and synthesizing phytohormonal substances. Inoculation of cucumber, tomato, and cabbage seeds had a beneficial effect on their germination. Presowing treatment of wheat seeds under conditions of a natural infectious background with an inoculum of the isolated bacterial strains contributed to a decrease in the spread of fungi that cause root rot. The possibility of using strains P. laurentiana ANT 17 and P. laurentiana ANT 56 in biotechnology in order to increase the productivity of agroecosystems is suggested. The ability to stimulate the growth and development of plants for P. laurentiana strains is shown for the first time.