Seasonal dynamics of functional parameters of wintergreen steppe relict Globularia punctata Lapeyr

Abstract

Globularia punctata Lapeyr. (Plantaginaceae) belongs to the ecological-historical group of pliocene relict plants. A distinguishing feature of the relict plant species is specific adaptability to particular habitat conditions (climatic, geomorphological, edaphic, and biological). The goal of the work was to study the structural and functional features of this species and their seasonal variability. We carried out a comprehensive analysis of the structure of the photosynthetic apparatus both at the level of cell morphology and at the level of membrane systems. Globularia punctata retained the viability of assimilation organs throughout the growing period. In winter leaves, the concentration of pigments remained at a high level. Seasonal changes in the leaf mesostructure were associated with changes in the number and size of cells and chloroplasts. The reorganization of the chloroplast ultrastructure due to the thickening of the thylakoids space, an increase in the number of plastoglobules, and intensive expenditure of starch prepared plants to overwintering. The maintenance of homeostasis in both the cell and plastids was provided by changes in the lipid composition and the content of fatty acids.