RESPONSE OF THE ANTIOXIDANT SYSTEM OF THREE BEAN VARIETIES (PHASEOLUS VULGARIS L.) TO SEED TREATMENT WITH A GRADIENT OF 6 BENZYLAMINOPURINE CONCENTRATIONS AS A MODEL OF THE INFLUENCE OF CYTOKININ-PRODUCING BACTERIA ON PLANT GROWTH

For successful application of bacterial preparations, it is important to determine the stimulating and inhibiting doses of the exogenous phytohormone affecting the growth of the host plant. Bean seeds were treated with different doses of 6-benzylaminopurine (BAP) 0.00001–10 mg/l. For the Ufimskaya variety, the stimulating doses were 0.01–0.1 mg/l, for the Elza variety – only 0.001 mg/l BAP, for the Zolotistaya variety – 0.001 and 0.1 mg/l BAP. In this case, the Ufimskaya and Zolotistaya varieties increased the development of adventitious roots, while the Elza variety increased the total root length. Individual varietal reactions of the antioxidant system in response to seed treatment with cytokinin were determined. The identified characteristics of the varieties highlight the importance of understanding the complex balance between phytohormone signaling and antioxidant defense mechanisms in plant-microbe interactions and necessitate the use of precision doses of growth regulators and cytokinin-producing bacteria to specific varieties to stimulate growth.