DYNAMICS OF PIGMENTS CONTENT IN SILPHIUM PERFOLIATUM L. LEAVES DEPENDING ON THE PHASE OF DEVELOPMENT AND SEASONAL FACTORS

The paper presents the results of studying the dynamics of the content of pigments in the leaves of Silphium perfoliatum L. (family Asteraceae), growing in the zone of unstable moisture of the Central Ciscaucasia, depending on the phase of development and seasonal factors. S. perfoliatum is a valuable forage, melliferous and flower-ornamental crop, which is also of interest as a source of various biologically active substances: terpenoids, triterpene saponins, polyphenols, polysaccharides, and others. Using the spectrophotometric method, the content of chlorophyll a, chlorophyll b, and the amount of carotenoids were determined in the leaves of S. perfoliatum variety Alena during 3 growing seasons (2018–2020 years). Changes in the content of pigments in plant leaves with a change in phenological phases have been established. The maximum content of total chlorophyll and total carotenoids in leaves was observed in the budding phase and over the years of the study averaged 0.75% and 0.15%, respectively (based on the absolutely dry weight of raw materials), in the flowering phase the amount of pigments slightly decreased and reached a minimum in the fruiting phase (0.52 and 0.12%, respectively). The content of pigments in leaves also depended on seasonal factors and increased with improved moisture conditions, which, in turn, depended on the amount of precipitacion. A sufficiently high level of pigment content in the leaves of Silphium perfoliatum L. allows us to consider them as a promising medicinal raw material containing chlorophyll and carotenoids, the collection of which should be carried out in the budding phase.