Evaluation of the Content of Steroid Phytohormones in Humic Preparations

It has been shown for the first time that humic preparations contain steroidal phytohormones— brassinosteroids (BS), the amount and composition of which vary depending on the source of raw materials and the method of its processing. It has been established that the qualitative and quantitative composition of BS correlates with the content of humic substances (humic acids). By the example of humic preparations obtained from sapropel, it was shown that alkaline treatment leads to the release of a noticeable amount of BS present in the form of conjugates. These results indicate that BS are important components of humic preparations and undoubtedly contribute to a wide range of physiological effects of these agricultural preparations.