ADAPTIVE STRATEGIES OF GENTIANA L. SPECIES UNDER THE CONDITIONS OF UKRAINIAN CARPATHIAN HIGHLANDS

Abstract

Peculiarities of adaptive strategies of rare species of Gentiana lutea L., Gentiana punctata L., Gentiana acaulis L., which allow them to survive in the highlands of the Ukrainian Carpathians, are analyzed. The ability of these species to survive in the highlands is determined not by their individual adaptive properties, but by the integrated interaction of morphological, anatomical, physiological, biorhythmological, reproductive and other features, which increase the adaptability of plants to specific habitats and shape their individual survival strategies.
The findings show that the formation of semi-rosette structures in plant species of G. lutea, G. punctata, and G. acaulis is a morphological property that allows them to exist in specific conditions of the highlands, where the surface layer of air is heated better. A number of passive and active mechanisms of protection of generative organs are revealed.
The upper leaves of monocarpic shoots of G. lutea and G. punctata together with the membranous cups create a kind of "micro-greenhouse" that protects the ovary from temperature changes. Both species are characterized by alternation of flowers in the inflorescence, which reduces the risk of damage in case of sudden frosts and belongs to the group of active adaptations that provide a favorable temperature for the development of generative organs of plants.
The corolla of G. punctata plants is densely covered with dark spots, and in G. acaulis plants it has a bluish color with olive-green spots. This is a sign of high content of anthocyanins, the biosynthesis of which is enhanced at low temperatures and increase the background of UV radiation and partially compensates for the lack of thermal energy in plants and protects them from short-wave radiation.
There is a correlation between the size of the corolla in plants and the hypsometric level of growth of species: increase in altitude above the sea level leads to size increase too. All species are characterized by a break in flowering and high life expectancy, which allows plants to restore the supply of nutrients necessary to ensure the processes of life, including seed production during a short-term vegetation period. These species are also characterized by miniaturization of morphometric parameters, which is a manifestation not only of interspecific features, but is also typical of the given species due to the localization of its populations at different hypsometric levels. The study demonstrated that differences in living conditions also affected the duration of functioning of rosette leaves. In species with lower hypsometric growth levels (G. lutea and G. punctata) only immature plants belong to the group of evergreen plants, and in the alpine species of G. acaulis - plants of all stages of ontogenesis. This allows plants to carry out photosynthesis immediately after the snow melts. The research findings reveal that the growing conditions also affected the morphology and anatomy of underground organs, which in G. lutea and G. punctata are represented by perennial additional storage roots with strong parenchymal secondary wood and interxylary phloem. In G. acaulis, the root system is represented by thin additional roots, which are characterized by moderate parenchymatization of the secondary phloem and xylem. Accordingly, it affects the storage of nutrients, the depot of which in G. lutea and G. punctata has a root system, and in G. acaulis - a rosette of leaves. The peculiarity of these species is the absence of root hairs, which is compensated by the development of arbuscular mycorrhiza, which is the result of symbiosis with glomus fungi (Glomeromycota).