Combined Effect of Brassinosteroids and Ferulic Acid on the Initial Growth of Spring Wheat Plants

Abstract

The growth-regulating effect of 24-epibrassinolide, 24-epicastasterone, and ferulic acid was studied at the initial stages of ontogenesis of spring wheat plants (Triticum aestivum L.) when used separately and together as was their effect on the endogenous balance of phytohormonal steroids and the dynamics of some physiological processes. The compounds and their mixtures were applied by soaking the seeds in solutions of the substances for 24 h. The concentrations of brassinosteroids used for the study (10^–7 and 10^–9 M) were selected during previous experiments because they showed a stimulating effect on growth processes. Ferulic acid in mixtures and separately was used in equimolar dosages. Plants were grown for 3 weeks in soil culture. Samples (leaves) for analysis were taken on days 7, 14, and 21 from the start of seed treatment with solutions of substances. It was shown that presowing treatment of seeds with brassinosteroids or ferulic acid led to activation of growth functions and an increase in the level of endogenous brassinosteroids, free radical oxidation, and pigments in the leaves. When brassinosteroids and ferulic acid were used together, their effectiveness increased. The study of the differentiated and combined effects of phytohormonal steroids and ferulic acid showed that these compounds exhibit, to a greater or lesser extent, a synergistic interaction in stimulating growth and metabolic processes.