Tserkovniak L. Biologically active compounds of Azotobacter vinelandii ІМV V-7076 and Bacillus subtilis ІMV V-7023 and their influence on plants.

The object of the thesis is was to study the effect of bacterial preparation with complex action on growth, development and yield of plants, identification of biologically active substances with positive effect in the cultural medium of the bacteria. Bacteria B. subtilis IMV V-7023 and A. vinelandii IMV V-7076 - the components of the preparation - have been shown to stimulate germination of plant seeds and development of their germings. B. subtilis IMV V-7023 has been established as one of the most active antagonists against a considerable spectrum of phytopathogenic bacteria and micromycetes in comparison to other phosphate-mobilizing bacteria. The ability of B. subtilis IMV V-7023 to produce phenylacetic and 4-hydroxyphenylacetic acid has been shown for the first time. 4-hydroxyphenylacetic acid was shown to stimulate growth of plant up to 8% and inhibit growth of some phytopathogenic micromycetes. Besides indolacetic acid A. vinelandii IMV V-7076 has been shown to produce a number of other compounds of indol group the quantitative and qualitative composition of those was different for different strains. The computer program PASS was used to estimate biological activity of aromatic compounds isolated and identified in the cultural medium of the studied bacteria. The granulated bacterial preparation with complex action comprised of A. vinelandii IMV V-7076 and B. subtilis IMV V-7023 was shown to increase the yield of seeds sugar beet up to 37,8%.