The article presents the results of a comparative analysis of the chemical composition of ultrafine

particles of the substrate of the greened rock dump of the Dimitrov mine 5/6 (Donetsk, DPR) before and after planting a test hyperaccumulator of winter rapeseed pollutants. There is an active absorption of all studied elements by rapeseed in winter (a decrease in concentration from 1.5 to 300 times). This justifies the use of winter rapeseed as a hyperaccumulator of ultrafine pollutants with further collection of shoots, processing and separation of rare and useful metals from biomass and their further use for industrial purposes. It has been established that nanoscale pollutants have a high inhibitory effect and are actively absorbed by winter rape. Rapeseed has the highest phytoremediation potential in relation to silicon, aluminum, vanadium, and sulfur. It is proved that the content of ultrafine pollutants in the substrate does not affect the germination and germination energy of the seeds of the hyperaccumulator test. The introduction of humic fertilizers can help accelerate and improve plant growth. For maximum utilization of useful metals from rock dumps using plants, additional research is needed to identify ultrafine particles that are non-toxic in high doses, as well as plants resistant to high concentrations of ultrafine pollutants.

The article presents the results of a long-term (2013-2019) agroecological study on the effectiveness of zeolite tuffs from deposits in South Ossetia (Vanat, Pris, and Eredvi) as ameliorants and components of organomineral fertilizers. The work was carried out on alluvial soils of the Bolshaya Liakhva River valley with the oat crop of the "Astor" cultivar (Avena sativa L.). The methodology included vegetation experiments (Wagner vessels) and field trials. It was found that zeolites increased the field germination of oats by 3.056.09%. The highest yield increase (+7.3%) was achieved with the application of Pris zeolite (5 t/ha). Complex organomineral mixtures based on zeolites increased the above-ground phytomass by 98.8%. The use of local zeolites, especially in combination with organic matter, showed high agroecological and economic efficiency, which substantiates their use for soil amelioration and increasing crop yields in the conditions of South Ossetia.

One of the important tasks of botanical gardens is to create new exhibitions that will demonstrate the diversity of their collection of plants. In the laboratory of ornamental plants of the Main Botanical Garden, next to the new storage greenhouse, a large landscape exhibition has been created, which aims to create highly decorative areas throughout the year. It consists of plants from six collections of woody plants Philadelphus L., Spiraea L., Hydrangea Gronov ex L., Cornus L., Physocarpus (Cambess.) Raf., MalusMill. and includes 24 species and 203 cultivars. The article formulates the basic principles of creating an exhibition collection and highlights the main and most spectacular representatives of each collection, depending on the season. 

The possibility of using biotechnology methods for the conservation and reproduction of Lilium pilosiusculum (Freyn) Miscz. (lily saranka) and L. pumilum Delile (dwarf lily) is shown. The aim of this study was the optimization of in vitro cultivation technology of two lily species to accelerate ontogenesis and obtain mass planting material for the introduction and reintroduction of plants. Seeds of plants obtained from specimens grown at the exposition of ornamental plants of the Siberian Botanical Garden of Tomsk State University were used as primary explants when introducing species into in vitro culture. The highest values of morphometric parameters of L. pilosiusculum plants (linear dimensions and number of leaves, roots, number of microbulbs) were obtained jn the modified MS medium supplemented with 6-benzylaminopurine (6-BAP) at a concentration of 0.4 mg/l: and 1 mg/l kinetin (KIN) + 0.1 mg/l indole-3-acetic acid (IAA). Linear parameters of microbulbs had low variability. In L. pumilum, the greatest number of roots and leaves was formed with growth regulators, but the largest microbulbs and leaves were formed on the hormone-free medium. The plants were planted in sterile substrates, and then in cups filled with a nutrient mixture for subsequent growing and planting in open ground. 

The fruits of jujube have valuable nutritional and medicinal value, as they contain many biologically active compounds (vitamins, microelements, amino acids, etc.). The fruits are consumed fresh and processed.

A pomological description and chemical analysis of fresh fruits of 5 jujube cultivars bred in the Nikitsky Botanical Gardens were conducted. The domestic cultivar Koktebel (average weight 21.66 g) and the introduced cultivar Ta Yan Tszao (Lang, Junzao) (average weight 14.52 g) were characterized by high commercial qualities of fruits. Cultivars with sour (Meteor), sour-sweet (Koktebel) and sweet (Yalita) tastes were selected. Fresh fruits of the cultivars bred in NBG-NSC are characterized by a high content of sugars (23.22-27.02%), ascorbic acid (269.45-511.81 mg/100 g). The titratable acidity varied the most among cultivars, amounting to 0.32-1.22%. 

The life form (LF) of plants reflects their adaptation to past and current soil, climatic, and cenotic conditions of their habitats. A distinctive feature of fern-like plant classifications (Polypodiophyta, including Lycopodiophyta) is the need to consider both the structure of sporophytes and gametophytes. The study of the morphological structures of fern gametophytes, begun in the 19th century by German botanists, revealed the importance of using comparative morphology in approaches to the classification of ferns (Orth, 1936; Goebel,

1928). The methods of spore germination were analyzed by S. Momose (1937 a,b; 1938 a,b,c; 1939; 1941; 1942). The author distinguished three types of germination: centrifugal, tangential, and centripetal. Nayar B.K. and Kaur S. when studying pteridophytes of India proposed a new classification, which reflected all existing types of germination of spores and formation of prothallia. J.E. Warming (1884), when distinguishing the life forms of ferns, distinguished two groups: I main (3 subgroups) the smallest and II main (2 subgroups, 3 types) with many variants and subvariants. The first approaches in our country to the allocation of LF of plants were successfully developed by I.G. Serebryakov for higher angiosperms (Serebryakov, 1964), where spore plants were not considered. The first classification of spore plants (ferns, horsetails and club mosses) was reflected in the works of A.P. Khokhryakov (1976) and Shorina N.I. (1994). When studying ferns of the south of the Russian Far East, O.V. Khrapko (1996) developed a fairly detailed classification that identified 14 morphological types of fronds, 6 types of branching and 15 types of rhizomes, which ultimately identified 15 LF of the above-ground and underground parts of ferns. A number of authors (Halle, Oldeman, 1970; I.I. Gureeva (2001)) proposed the term "architectural model" which is based on a dichotomous key in the consideration of underground rhizomes and contains a large number of models, types, groups, sections, variants, but does not reflect the biomorphological features of the perennial structure for fern’s-like plants. According to some authors (Serebryakov, 1964; Raunkiaer, 1934) the concept of modularity in the classification of LF of ferns, which is developed on non-ecological principles, the "architectural model" cannot be recognized as the structural basis of a life form. Raunkiaer developed (1934) a classification in which 131 biomorphs from the main 13 and 185 variants are distinguished. For fern-like plants of the boreal, subtropical and tropical zones, distinguished by the presence of evergreen and tree-like species, we are segregated classification of plant life forms, based on the classification of Ch. Raunkiaer (1934), with additions according to T. Hosokawa (1949) for epiphytic plants, which includes 12 main life forms and 31 variants. 

The paper examines seed renewal of Taxus baccata L. in natural populations in the Mountain Crimea. Field studies were conducted at four sites located at altitudes of 220–1,200 m above sea level. The seedlings were counted on 10 m wide transects, where their number, age structure, and condition were determined. It was found that regeneration is patchy and occurs mainly in areas near parent trees. The number of seedlings ranged from 150 to 250 per hectare. The age structure is characterized by a predominance of younger age groups, with a very limited transition to older age groups, especially in the eastern and northern areas. A higher proportion of healthy plants was recorded in the south and west, while stunted individuals predominated in the east and north. An additional limiting factor was mechanical damage caused by falling branches from the first tier of trees. The results obtained clarify the understanding of seed renewal of the common yew in Crimea and can be used to develop measures for the conservation of the species.

Monitoring studies of rare species under conditions of climatic changes are very relevant. One of the rare species of Crimean flora is the endemic petrophyte (obligate chasmophyte) Silene jailensis. Control observations of the largest population of the species on the Nikitskaya yaila have been going on for 20 years. Over the years, the population parameters have changed significantly: the predominance of plants in the middle and late age groups has been replaced by the dominance of plants of the virginal and early generative ages. The same process was observed for the population on the Gurzuf yaila. In addition, the late generative group is rapidly dying out in the studied populations. Thus, climatic transformations act as the main destabilizing factor threatening the existence of a rare endemic of the Crimean flora. 

A study was conducted to develop an optimal composition and an effective method for extracting biologically active substances to create a phytocomplex with an immunomodulatory effect based on medicinal plant raw materials. The composition of the phytocomplex, including 12 plant species, was substantiated: Chinese magnolia vine, rose hips, large-cupped primrose, linden, fireweed, lemon balm, oregano, raspberry, common sea buckthorn, peppermint, thyme, and black currant. An effective method for extracting biologically active substances was developed, involving the combined use of 70% and 90% ethyl alcohol, extraction using countercurrent periodic extraction in percolation and repercolation modes, and extraction using gas-liquid extraction with liquefied CO₂ (for sea buckthorn fruits). The qualitative and quantitative content of biologically active substances (ascorbic acid, total flavonoids, total carotenoids, phenylpropanoids, and water-soluble polysaccharides) in the resulting extracts was determined.

Isatis tinctoria L. (woad) is cultivated in China as a medicinal plant, and its leaves and roots are included in the Pharmacopoeia of the China. Carotenoids ensure a protective function by scattering light flux, absorbing in the blue-green spectrum, and are healthful for humans. The dynamics of leaf weight, leaf growth, and photosynthetic pigments throughout the entire life cycle reveal the biological characteristics of woad cultivation and are therefore of interest. The aim of this study is to investigate the characteristics of certain biometric parametres, as well as the content of chlorophylls a and b, and carotenoids in woad leaves in the first and second years of life in two cultivar populations (China and Russia) and the Ariana variety. At the rosette stage at the end of the growing season, the studied variants differed in leaf weight: in the series Ariana > Russia > China, leaf weight gradually decreased (2.3 ÷ 1.4 g). During budding and flowering, leaf weight varied in the order RF > Ariana > PRC, and the studied populations/variety in this set of varied in leaf length within the range of 6.3–8.2 cm. The amount of photosynthetic pigments in the rosette leaves of the Ariana cultivar is 1.37 times higher than in the stem leaves. A different dynamic is observed among cultivar populations: the amount of photosynthetic pigments is higher in the stem leaves than in the rosette leaves by 9.7–32.9%.

The antifungal activity of the Monarda citriodora Cerv. ex Lag. hydrolate and essential oil against an Alternaria alternata (Fr.) Keissl. isolate, obtained from infected Monarda leaves, as well as mycocomplex, developed on the lateral photosynthetic organs of the essential oil-bearing plants M. didyma L. and M. fistulosa L., grown in the collection plots of the Nikita Botanical Gardens, was evaluated. In laboratory studies were performed that hydrolat showed no significant inhibitory effect on fungal phytopathogen. The essential oil of the thymol chemotype (thymol 62.84%, carvacrol 7.20%) completely inhibited mycelial growth as concentrate and in the diluted form of 1:25 to 1:50. In the field experiments conducted on M. didyma and M. fistulosa plants naturally infected with a complex of fungal pathogens, treated the composition, comprising the diluted essential oil (1:25), did not result in a significant reduction in infection development. Phytotoxicity was observed (chlorosis, drying, leaf drop). The high antifungal activity of the essential oil in vitro is due to the dominance of phenolic compounds. The results indicate the potential of the essential oil as a biofungicide, provided that formulations are optimized to reduce phytotoxicity.

This article presents the results of a multi-year (2021-2024) introduction study of lemon balm (Monarda citriodora Cerv. ex Lag.) in the temperate continental climate of the Crimean Steppe (Northern Sivash region) to determine the potential for cultivating this crop as a source of valuable medicinal and essential oil raw materials. Monarda citriodora is an annual plant of the Lamiaceae family, native to North America. Plants were grown under drip irrigation without mineral fertilizers. The phenological development of the aboveground mass productivity, as well as the dynamics of the essential oil content and component composition, were studied. It was found that, in the conditions of the Crimean Steppe, the species goes through all stages of development, the vegetation period is 152-163 days, forms viable seeds (seed germination rate of 95%), and is not damaged by pests and phytopathogens. The average yield of the aboveground mass is 168.6 ± 19.9 kg/m². The content of essential oil in the aboveground mass of plants during the mass flowering phase is 0.67–0.7% of the fresh weight, the oil yield is up to 1.14 kg/m². The mass fraction of the major components of the essential oil - thymol (65.95-69.96%) and carvacrol (6.63-8.63%) - allow us to classify it as belonging to the thymol chemotype. It was found that the essential oil from inflorescences accumulates more thymol (on average 68.93%) and carvacrol (9.20%) compared to the leaves. Despite the contrasting weather conditions of the study period, the chemical profile of the essential oil remains stable, which indicates its genetic determination. The data obtained demonstrate the potential for industrial cultivation of M. citriodora in the Crimean steppe zone as a highyielding essential oil crop with valuable pharmaceutical-grade plant material. 

The effect of lemon essential oil (EO) (Citrus limon L.) on elderly people when they inhale air containing vapors of lemon EO at a concentration of 1 mg/m³ has been studied. It was found that lemon EO has anxiolytic and antidepressant effects, improved self-esteem, mood and relaxation, and accelerated work with arrays of symbols. It is shown that the effect of lemon EO on a person's psychoemotional state and mental performance depends on the duration of exposure: the positive effect is manifested mainly with prolonged (30-40 minutes) exposure.