The introduction experience of East Asian maples Acer japonicum Thunb. and A. palmatum Thunb. in the Nikitsky Botanical Gardens (NBG) from 1821 till 2017 is presented. Bioenvironmental and decorative characteristics of these species and the most stable cultivars, sorts and varieties are given. The negative weather and climate factors influencing on the growth and development of these plants in the Southern Coast of the Crimea are specified. The methods of preservation East Asian maples in the Southern Coast of the Crimea are determined. The list of alternative maple’s varieties with similar decorative qualities is given.

The peculiarities of the formation of park complexes in the Southern Coast of the Crimea (SCC), including historical and environmental aspects are presented. The stages of cultural-phytocoenosis’s formation in the SCC are given. The role of the Nikitsky botanical Gardens in the processes of plants introduction in the Crimea are shown. The layout of favourable territorial zones for the placement of thermophilic of exotic species within the Big Yalta is designed. The results of works on preparation of projects of maintenance and reconstruction of parks "Haraksky", "Gurzufsky", "Karasansky", "ay-Danil" and "Pribrezhny" are summarized. The principle of allocation of the structural and functional subzones as a part of the exposition zone, based on the differentiated approach to the mode of conducting works on preservation and optimization of park territories is offered.

The phytopathological and entomological inventory in three parks of the arboretum - the Upper Park, the Lower Park and Montedor has been performed. 926 foci of pathogens have been identified; among them 140 - fungal diseases, 20 species of fungi; 716 pests, 18 species; bacterial diseases - 4 foci; flowering hemiparasites - 35 foci, 1 species; tree hollows as potential sources of stem and root rot - 31. Pathogens and range of host plants for each species have been identified, it gives the opportunity to forecast the development of pathogens.

The results of the study of the influence of ground-cover plants (European ivy and small periwinkle) on the water-nutrient regime of agro-brown soils of the parks of the Nikitsky Gardens are summarized.

The data about peculiarities of selection of varieties of micranthous chrysanthemum Chrysanthemum×morifolium Ramat., the collection of the Nikitsky Botanical Gardens, for flower panel arrangement are presented. The description of varieties, blooming period, recommendations for use are given.

The results of the primary introduction of Galanthus elwesii and G. ikariae in the Republic of Mordovia are presented. The morphometric parameters of plant individuals (leaf size (length / width, height of the peduncle, fruit length), phenology, and the coefficients of vegetative reproduction are presented. It is shown that in the Republic of Mordovia these species cannot be widely used for mass introduction due to the low coefficient of natural vegetative reproduction (K = 0.52-0.67) and rare dissemination.

The action of the essential oil of the rose of the Krymskaya Krasnaya variety of different duration on the functional and psychophysiological parameters and parameters of the cardiovascular system in order to assess the possibility of using this essential oil in aromatherapy for the elderly has been investigated. The actions of rose essential oil have a hypotensive effect and contribute to normalization of cardiovascular system of the elderly with hypertension when using 10, 20 and 30 minute sessions aroma-relaxation.

Some stages of morphogenesis in vitro in relict endemic of the Crimean Mountains flora of Scrophularia exilis Popl. were investigated. Possibility of in vitro micropropagation was demonstrated. The morphogenetic capacity realization in investigated species through direct organogenesis (activation of internodes meristems, development formation of microshoots and microrosettes) was determined. It was established that MS and QL media supplemented with BAP, IBA and GA3 significantly increased the efficiency of in vitro regeneration process in relict endemic species.

The study of Sorbus Roopiana Bordz. growing on Babugan-yaila has been performed. 40 specimens have been revealed. The geographical coordinates of the places of growth are determined, the taxi indicators are set: age, height, diameter of trunks and crowns. The description of environmental conditions of places of growth is accomplished. The list of 53 species of woody, herbaceous plants and ferns, typical of places of growth of Sorbus Roopiana , which can be used as indicators in search of new places of growth of this species is given. The analysis of quality of 145 fruits is made, potential and real seed productivity is defined. The comparative biochemical analysis of fruits of three close species of the Crimean mountain ash is carried out, the results testify about the possible hybrid origin of a Sorbus Roopiana Bordz. from Sorbus aucuparia and Sorbus graeca.

The distribution of Poacynum armenum (Pobed.) Mavrodiev, Laktionov & Y.E. Alexeev in the south-western Crimea has been determined and the status of its populations has been analysed. History of the study of the taxa in this region has been covered. Six populations of sword-leaf dogbane have been found. A brief description of the habitats and the main parameters of the populations have been given. The major threats have been evaluated and recommendations for the species conservation have been proposed.

In the presented article some data are given on the study of the biochemical composition of fruit processing products from different varieties of persimmon ( Diospyros kaki L.) growing in the collection stands of the Nikitsky Botanical Gardens. Jams and dried fruits that are promising in terms of their content of biologically active substances are identified.

The research paper presents the results of two-year studies of the adaptive potential of Cydonia oblonga Mill. plants and 10 genotypes of chaenomeles of different species ( Chaenomeles x superba , Ch. chinensi s, Ch. spesiosa ), obtained in the most droughty period of summer, in August 2016-2017. The dynamics of indices of water cut and water deficiency in leaf tissues was studied, the degree of water retention capacity and the level of reparation ability under the conditions of water stress in the Southern Coast of the Crimea were determined.

The results of studies on the productivity of cherry trees on the rootstock of VSL-2, depending on the methods of crown formation. The objects of research were plants of varieties Krupnoplodnaya, Lyubava, Annushka, which are formed by the type: free-growing spindle (control), flattened spindle, weeping crown shape. The scheme of planting - 4.5 x 2.5 m. The results of the research showed that the average yield for the period 2013-2016 in the plantings of Krupnoplodnaya variety was 17.6 t/ha in the formation of free-growing spindles (control); 17,0 t/ha - flattened spindle and 19,1 t / ha - weeping crown shape. The average yield of varieties Lyubava and Anushka during this period did not exceed 7.9 t/ha, but they stand out for the quality of the fruit and are resistant to cracking and gray rot. The highest yield was found in varieties Lyubava version with a weeping crown shape (6.4 t/ha), in varieties Anushka - in the formation of trees on the type of flattened spindle (7.9 t / ha).

The article presents the model criteria of the fig cultivar that meets modern demands. A comparative rating, based on 16 main economically valuable characters, is given for marked out 21 cultivars from the feature fig collection, being realized in compare with a model of the cultivar due to cluster analysis. Two cultivars ('Zheltoplodny Urozhainy' and 'Sabrutsiya Rozovaya’) of the Nikitsky Botanical Gardens breeding and five introduced cultivars (Randino, Bleuet, Figue grise, Brunswik, Pomorijsky) were found as the closest to cultivar model ones. Pair correlations for economically valuable characters were also determined.

Detailed assessment of temporal dynamic of growing season when average temperature is above the thresholds at 5, 8, 10, 15, 20°C as well as date of the last spring and first fall frost in the Southern Coast of the Crimea for the 1930 to 2017 period has been performed. It is revealed, that during the recent years there is extensions of the duration of the frost-free season, the growing season (Tav. > 5°C) and the hottest part of summer season (Tav. > 20°C) have been enduring longer as well. The period of active vegetation with average daily air temperatures above 10°C has the most stable duration and terms of spring threshold. The frequency of late frost events is likely to increase in future as a result of ever earlier vegetation onset in the spring, due to climate warming.