It has been established that 22 species of the genus Polygonum L. s. str. grow in Donbass. It is recommended to include P. maritimum L., P. mesembricum Chrtek, P. euxinum Chrtek in the regional Red Book. Rare species are P. patuliforme Worosch., P. capsicum Kom., P. aschersonianum H. Gross, P. pulchellum Loisel. Alien species include: P. rigidum B. Skvortsov, P. rurivagum Jord. ex Boreau, P. sabulosum Worosch., P. bellardii All., P. argyrocoleon Steud. ex G. Kuntze. They do not pose an invasive threat.

In the artificial steppe phytocenoses of the Donetsk Botanical Garden, the ontogenesis of Polygala cretacea Kotov is simple, it lasts for one seed generation. Eight ontogenetic groups of plants have been identified. Plants die in the old generative and subsenile stages. Polygala cretacea has a complete shoot development cycle annually, producing viable seeds and self-seeding. Introduced populations of this species are normal, have one-peak, centered ontogenetic spectra and stable density of individuals, distributed contagiously in space. According to the «Δ–ω» classification, the populations are maturing and mature. These are definitive systems capable of self-sustaining by seeds. P. cretacea forms a reliable reserve of rarity gene pool and has good prospects for ex situ conservation.

The article presents the results of a biomorphological analysis of 51 species of the genus Salix L. in the western part of Baikal Siberia. The species were assigned to 10 biomorphs belonging to four main groups (tree, tree-shrub, shrub and dwarf shrub). Using a digital elevation model, elevation parameters were determined for all occurrence records. The distribution of species across three elevation complexes was revealed: elevated plain, low-mountain and mid-mountain. It was found that with increasing of absolute altitude, larger biomorphs are replaced by smaller ones, reflecting the adaptation of species to
high-mountain conditions.

Based on research conducted between 1995 and 2026, the composition (197 species; 68 % of the fauna of Udmurtia) was established and a comprehensive analysis of the fauna of leaf beetles (Chrysomelidae) was conducted in Izhevsk. A comparison of leaf beetle complexes in different ecological zones of the city and types of biotopes made it possible to identify trends in the transformation of fauna in the urban environment. In the residential zone, given the highly mosaic environment and the preservation of remnant natural biotopes, the species richness of leaf beetles is only slightly lower than in the city’s green zone (155 versus 182 species). A significant depletion and transformation of leaf beetle complexes (a significant increase in the proportion of ruderal and eurybiont species, as well as the adventitious component of the fauna) are observed in typical urban areas. Almost all adventitious species (16 out of 17) are near-field invaders, having entered the city from the major river valleys of the republic’s south or the Trans-Volga forest-steppe zone. The Colorado potato beetle – Leptinotarsa ​​decemlineata (Say, 1824) is an invader from remote regions.

The article presents the results of a retrospective analysis of the cultivar assortment formation of garden rose (Rosa × hybrida hort.) for urban landscaping in Donetsk. Based on archival materials, periodicals and specialized literature on landscaping and floriculture, the development of the assortment from the 1930s to the present has been reconstructed. The chronological stages have been identified, characterized by a shift in the dominant garden classes from polyantha roses to hybrid tea and floribunda ones, which reflects global trends in rose selection and introduction; the leading cultivars of each period have been determined. Field surveys identified 65 garden rose cultivars that form the basis of the current assortment. It is recommended that the regional assortment be periodically updated with promising cultivars that have passed introduction trials at the Donetsk Botanical Garden.

The paper presents the results of the analysis of ornamental deciduous and evergreen shrubs in green spaces of the Southeastern coast of Crimea. The cultivated dendroflora of the study region includes 126 shrub species and cultivars belonging to 63 genera from 31 families. Deciduous shrubs predominate (64.3 %), the majority of them (61.0 %) are ornamental flowering with different data and duration of blooming. The paper provides blooming periods for some of these shrubs. Shrubs blooming in summer and autumn-winter periods are of particular importance for the region with intensive recreational use. The materials of this study can be used in developing an assortment of ornamental plants for green spaces on the Southeastern coast of Crimea.

Analysis of patterns of formation of dimensional parameters of leaf blade of Psidium guajava L. in greenhouse conditions of Donetsk Botanical Garden was carried out. Average parameters of leaf blade length vary within the range from 5.91±0.08 to 19.23±0.21 cm; average parameters of width – from
4.16±0.09 to 8.29±0.09 cm. Statistically significant differences were found in the sizes of leaf blade located in different nodes of the annual shoot. Consistent increase in sizes of leaf blade of the studied species from the first to the fifth pair was noted, then a consistent decrease in sizes was established. A consistent increase in the size of leaf blades located in the first five nodes of the shoots was noted; after reaching the maximum value, a progressive decrease in the size of all subsequent leaf blades was established. Leaf blade length and width parameters show little variation, with the coefficient of variation being less than 10.0 %. A high positive correlation was found between the length and width of the leaf blade of P. guajava.

In the dendrological collection of the Stavropol Botanical Garden, the genus Juniperus L. is represented by 35 cultivars belonging to 8 species. The average age of plants is 30 years. The groups: quite promising (91–100 points) include 24 cultivars (68.6 %) and promising (76–75 points) – 11 cultivars (31.4 %). The easily rootable cultivars include 15 ones (50.0 %); those with an average degree of rooting ability –
14 cultivars (46.7 %), hard-to-root – J. virginiana ‘Glauca’. Percentage of rooted cuttings in the variants using Ribav Extra and Kornevin is higher compared to the control: in Juniperus horizontalis ‘Wiltonii’ (73.3 % – using Ribav Extra, 76.7 % – Kornevin, 56.7 % – in control), J. squamata ‘Blue Carpet’ (96.7 %, 100 %, 46.7 %), in J. chinensis ‘Blue Cloud’ (66.7 %, 76.7 %, 65.3 %), J. chinensis ‘Pfitzeriana Aurea’ (83.3 %, 73.3 %, 66.6 %) и J. horizontalis ‘Glauca’ (96.7 %, 93.3 %, 86.7 %).

The paper presents results of a long-term (2022–2025) introduction study of 9 varieties and a collection of 107 hybrid forms of small-flowered chrysanthemum (Chrysanthemum × morifolium Ramat.) in the arid conditions of the Stavropol Upland. As a result of the initial assessment of the entire hybrid fund, the most promising samples (5/2022, 10/2020), which showed high adaptability, were selected for detailed analysis. Patterns in phenological rhythms were identified, and a correlation was established between flowering time and the sum of effective temperatures (r = –0.89). Promising varieties (‘Bronze of Autumn’, ‘Wild Honey’, ‘Golden Amphora’) and hybrid samples (5/2022, 10/2020) were selected based on a set of ornamental and economic-biological traits. Hybrid forms were found to show greater resistance to extreme temperatures and moisture deficit compared to introduced varieties. The proposed list of varieties is suitable for use in landscaping arid regions of the southern part of the Russian Federation.

Representatives of the genus Euonymus L. accumulate fatty oil in their seeds and arils and are of interest as high-oil-bearing plants. Studying fruit formation and the accumulation of dry matter and crude fat is important. The fruits of E. macropterus Rupr. have the highest dry matter content in the pericarp. Dry matter accumulation follows a broken curve similar to a sigmoid curve. Dry matter accumulation in seeds and arils occurs in parallel along a double-sigmoid curve or is nearly linear; in arils it is faster but in smaller quantities. The dynamics of crude fat accumulation in arils and seeds are described by a sigmoid curve. The maximum value in arils exceeds that in seeds, but is reached 1–2 weeks later.