THE STUDY OF ANTIBACTERIAL PROPERTIES OF EPIN-EXTRA PLANT GROWTH STIMULATOR TO OBTAIN ECOLOGICALLY CLEAN PRODUCTS
The research evaluates the influence of Epin-Extra plant growth stimulator based on brassinosteroid plant hormone on certain bacteria. The test objects were potentially pathogenic strains of bacteria Bacillus subtilis, Escherichia coli, Staphylococcus aureus and Bacillus megaterium extracted from soil. Different concentrations of the product obtained by dilution of the mother liquor with a concentration of 1 mg ml of active material were tested. The microbiological methods, namely the method of product diffusion into the medium, were used to study the effect of the product on the growth and development of bacteria. The diameter of delayed growth of bacteria on the third and fifth days of bacterial growth was measured. The findings showed that the product of a steroid phytohormone epibrassinolide Epin-Extra and has an antibacterial effect. The most effective antibacterial product is the epibrassinolide solution in a concentration of 10 <sup>-5</sup> mg ml. On the contrary it was also found that some concentrations of the product (10 <sup>-3</sup> and 10 <sup>-7</sup> mg ml) promote more intensive growth of bacteria and may be used in future as growth stimulators for some species of beneficial bacteria. For example, the product of certain concentrations may be advised to stimulate the growth of bacteria B. megaterium which is used as a plant growth stimulator. Based on the obtained results it may be concluded that Epin-Extra used as a plant growth stimulator in certain concentrations has an antibacterial effect and may replace some antibiotic substances. This may help to avoid chemical treatment of seeds and plants in order to obtain ecologically clean products.