The current state and biodiversity of steppe phytocenoses in the territory of the Kabardino-Balkarian Republic

In connection with the importance of preserving and restoring steppe landscapes, the purpose of the study was to monitor the state and biodiversity of steppe phytocenoses in the territory of the Kabardino-Balkarian Republic. Geobotanical survey was carried out in the steppe and foothill zones of the republic in 2018-2020. According to the monitoring results, it was found that an increase in pasture digression correlates with a depletion of the floristic composition, a decrease in the projective cover, the height of the herbage and the productivity of aboveground phytomass, an increase in the level of synanthropization and a simplification of the vertical structure. With an increase in anthropogenic influence in plant communities, the level of synanthropization increases to 78.6%. The decrease in the projective cover in 1.5-3.3 is a consequence of the long and irrational use of pastures. As a result of intensive grazing, the productivity of the aboveground phytomass decreases by 9-12 times, and the height of the grass stand - by 2.5-5.0 times compared to the reference steppe phytocenoses. To preserve steppe phytocenoses, a set of measures is needed, including the ecologization of agriculture, the development of measures for the ecological restoration of disturbed steppe ecotopes, the prevention of negative phenomena of invasion, the creation of nurseries of steppe flora and steppe reserves, the inclusion of species that are in danger of complete extinction in the Red Book of the flora of Kabardino-Balkaria

MICROMORPHOLOGICAL FEATURES OF THE EPIDERMIS AND HYSTOCHEMICAL TECHNIQUE OF IDENTIFICATION OF SECONDARY METABOLITES IN THE LEAVES OF BORAGINACEAE HERBAСEOUS PLANTS

Aim. In conventional medicine, the species of the Boraginaceae family are not used due to the poor scientific knowledge of the products of secondary metabolism and the lack of information about most of the species. We investigated micromorphological features of the epidermis and conducted histochemical analysis of the products of secondary metabolism in the leaves of Pulmonaria mollis Wulfen ex Hornem., Echium vulgare L., Symphytum asperum Lepech. and S. caucasicum M. Bieb. Methods. Micromorphological analysis included the study of the shape of the main cells of the epidermis, the structure of trichomes and stomata. The number of stomata and trichomes was calculated per 1 mm2. Were used the histochemical reactions in order to identify the products of secondary metabolism. Results. The studied species are characterized by the bifacial type of leaves, numerous trichomes, including long leaf fuzz with a rosette of epidermal cells. The anomocytic type of stomata is characteristic for P. mollis and E. vulgare, anomocytic and anisocytic for S. asperum and S. caucasicum. The leaves of P. mollis, E. vulgare and S. caucasicum are amphistomatic while S. asperum is hypostomatic. The ratio of the non- glandular and glandular trichomes of the intercostal zones of the lower epidermis to the upper in P. mollis was 1.08 and 1.83, respectively, in S. caucasicum 1.61 and 2.67, in S. asperum 7.21 and 2.50, in E. vulgare 1.65 (glandular trichomes in the interstitial zones are absent). In the leaves of the studied species, the products of secondary metabolism (tannins, alkaloids, essential oils, anthracene derivatives and mucus) are localized in bases of non-glandular, glandular trichomes, veins and the main cells of the epidermis. Conclusions. Genus signs of the epidermis of leaves of Boraginaceae are the structure and location of trichomes. Species differences are due to the location of stomata, glandular trichomes and shape of the main epidermal cells. The intensity of staining of secondary metabolites depends on their content in the leaves. The presence of biologically active substances in the leaves of P. mollis, S. caucasicum, S. asperum and E. vulgare determines the value of these species in the creation of new phytopreparations

MORPHOLOGY OF EXCRETORY TISSUE OF LEAVES AND SECONDARY METABOLITES OF SOME SPECIES FROM INULA GENUS

Aim. This work is devoted to studying the morphology of the excretory tissue of leaves and secondary metabolites of some species from Inula genus (Inula britannica L., Inula aspera Poir., Inula germanica L.) grown in plant communities of the foothill and steppe zones of the Kabardino-Balkar Republic. Methods. As object of a research served the leaves of an average tier of plants collected in a phase of the complete blossomingin August, 2015-2016. Applied the standard histochemical test reactions to identification of secondary metabolites. Results. Morphological structure of non-glandular trichomes are typical of the Asteraceae family. Hairs are located on large veins and interveinal region abaxial, rarely adaxial surface of the leaf. The total number of non-glandular trichomes decreases among I. britannica L. – I. aspera Poir. – I. germanica L. Glandular trichomes are located on the abaxial surface of the leaf and have morphological species characteristics. The number of glandular trichomes per 1 mm2 of the leaf surface varies from 1 (I. germanica L.) to 16 (I. aspera Poir.). In the leaves of I. germanica L. are formed endogenous secretory structures: schizogenous intercellular spacese, idioblast, latex vessel. The secondary metabolites of I. britannica L. are essential oils, I. germanica L. – essential oils, resins, calcium oxalate, rubber, I. aspera Poir. – essential oils, resins, polysaccharides. Conclusion. Morphological features of secretory tissue and chemical composition of secondary metabolites in the leaves of the genus Inula L. due to the influence of abiotic conditions and associated with the ecological strategy of the species. Differences in the morphology of glandular structures can be used for micro-diagnostics species of the genus Inula L

Accumulation of alkaloids in plants of the family Boraginaceae depending on environmental conditions places of growth

Due to the lack of information on the influence of environmental factors on the accumulation of pyrrolizidine alkaloids and their content in certain species of this family Boraginaceae, the aim of the study was to assess the level of alkaloids accumulation in the aboveground and under-ground parts of Symphytum asperum Lepech., S. caucasicum M. Bieb., Echium vulgare L., and Pulmonaria mollis Wulfen ex Hornem. depending on climatic, orographic and edaphic conditions. The localization of alka-loids in rhizomes with roots, glandular trichomes of leaves and stems, epidermal cells was revealed. The content of alkaloids in the aboveground phytomass decreases in the series S. asperum ˃ S. caucasicum ˃ Е. vulgare, and in the underground S. caucasicum ˃ S. asperum ˃ Е. vulgare ˃ P. mollis. At the end of the growing season, an increase in the accumulation of alkaloids in the underground phytomass and a decrease in the aboveground one were noted. An increase in air temperature and a decrease in precipitation contribute to an increase in the accumulation of alkaloids in roots and shoots. The level of correlation between the accumulation of alkaloids and the content of trace elements varies from high (Cu, Zn, Mo) to medium (Mn, Pb). The results obtained indicate the need to take into account environmental factors in the implementation of medicinal collections and the preparation of feed from plants