Особливості пігментного комплексу високогірних видів роду Gentiana l. флори Українських Карпат

Abstract

Досліджено вміст пігментів та їхнє співвідношення у фотосинтетичному апараті високогірних видів роду Gentiana L. З’ясовано, що їх кількість залежить як від еколого-географічних умов росту таксонів, так і стадії онтогенезу, на якій перебувають рослини. Проведено кореляційний аналіз між вмістом хлорофілів а і b, сумою каротиноїдів у хлоропластах рослин Gentiana lutea L., Gentiana punctata L., Gentiana acaulis L. і параметрами температурного та водного режимів існування цих таксонів. Встановлено, що серед досліджених видів пігментний комплекс рослин G. lutea найбільше залежить від показників температури повітря, ґрунту, відносної вологості повітря та суми опадів.

High-mountain species, including species of Gentiana L. genus, have a narrow range of tolerance to many environmental factors. By the beginning of the 21st century, the reduction of their habitats in the flora of the Ukrainian Carpathians was related only to scientifically ungrounded harvesting of medicinal raw materials and pastoral practices. However, in recent decades, climate change has become one of major threats. It is known that Gentiana lutea L., Gentiana punctata L., and Gentiana acaulis L. species are susceptible to the change of thermal regime of their habitats even by 2% (0.5 ° C or 100 J / m2). In response to the rise in the air and soil temperature and decrease in the amount of available groundwater, there is a decrease in the morphometric parameters of the vegetative organs of plants of G. lutea, their reproductive capacity, which also testifies to a decrease in the productivity of individual species, which depends on the photosynthetic apparatus (FA). Therefore, the research work aims to study the characteristics and contents of photosynthetic pigments and their correlation in plants of different age groups of high-mountain species of G. lutea, G. punctata, G. acaulis, as well as their concentration variations caused by temperature and water regime changes. These research studies do not only lay a groundwork for a more thorough analysis of the ecophysiology of these taxa, but also contribute to a successful implementation of programs for the re-introduction of their populations in the mountainous regions of the Ukrainian Carpathians under the conditions of climate change and global warming. The results of studies conducted in 2017–2018 demonstrate that the composition of pigments in FA plants of given species depends on the ecological and geographical conditions of their growth and the stage of ontogenesis. It has been revealed that immature and generative plants of all species contain the highest concentrations of pigments. This is due to the necessity to accumulate the nutrients as fast as possible in the short growing season and to ensure the survival, flowering and fruiting of individuals in extreme climate conditions. The study of the results of the correlation analysis showed a different degree of FA response in the given species to the change in the meteorological conditions. It has been discovered that the content of Chl a and Carot in G. lutea species depends on the amount of precipitation (r = 0.58, r = 0.64, respectively), and Chl b – on air humidity (r = 0.52). Therefore, due to the increase in the air temperature, the climate aridity can lead to the disappearance of this species. G. punctata and G. acaulis species showed a positive correlation between the contents of Carot and air and soil temperature numbers, by which these species cannot be considered as indifferent to climate.