The article presents the results of a study of the variability of quantitative characteristics of the fruits of their three cenopopulations of dogwood (Cornus mas L.) growing in the foothill zone of Dagestan. It was revealed that the weight of the C. mas fruit can vary widely from 442 mg to 2262 mg, and the bones 119-469 mg. According to the results of a one-factor analysis of variance, the growing conditions have the greatest influence on the signs of the width of the fruit (45.9%), the thickness of the fruit (45.3%) and the weight of the fruit (43.3%). An interesting wild-growing form has been identified for a number of economically valuable features. The yield of the tree is high, the compact shape of the crown, the fruits are oval in shape, with an average weight of 1.5-1.7 g, the skin and pulp are dark red with a juicy consistency. It is characterized by the presence of aroma, lack of viscosity. The yield of pulp is 80-85% (with an average of 70% for the sample).

A brief description is presented on economically valuable characteristics and indicators of resistance to environment stressors of seven new cultivars of sweet cherry of Dagestan breeding (DBESFC) are presented: Bela, Dagestanskaia krasnaia, Bigarro Krainskogo, Granatovaia, Liubimitsa Korvatskogo, Lezginka and Nike. It was determined that the cherry cultivars Liubimitsa Korvatskogo, Granatovaia, Bela and Nike are highly resistant to spring frosts - the freezing of flowers did not exceed 18.3%. The fruits of the cultivars Nike, Bela, Granatovaia, Lezginka and Liubimitsa Korvatskogo are the most resistant to cracking (13.5-18.2%) during ripening at high air humidity. Susceptibility in new cultivars to coccomycosis and monilial burn is negligible (less than 1.2 points). All new cultivars of cherries, with the exception of Bela cv. (5.0 g), are large (7.5-9.5 g). The best indicators of average yield (8.0-9.6 t/ha) were distinguished by Nike, Bela and Granatovaia.

The North Caucasus, including the Republic of Kabardino-Balkaria, is one of the main regions of Russia, supplying the population of the country with the products of the most valuable southern fruit crops (apricot, peach, cherry, etc.). Their cultivation here has certain difficulties due to the large mosaic relief. The apricot culture is particularly demanding on the temperature regime of the winter-spring period, and therefore the creation of new approaches to managing the production process of its cultivars by phases of development in difficult terrain is very important. New, in-depth approaches are presented to reveal the patterns of manifestation of the properties of specific genotypes in the phenotype, taking into account the changing growing conditions in the territory of Kabardino-Balkaria. The work is based on the latest strategy developed by the scientific school of V.A. Dragavtseva – the theory of ecological and genetic organization of quantitative traits (TEGOKP). The degree of adaptability of apricot cultivars of different frost resistance under different growing conditions for specific development phases over a long period of years (1985-2022) in Kabardino-Balkaria was studied. Graphical models have been developed to reveal the most vulnerable periods of the onset of temperature stressors in the winter-spring period under the conditions of climate change for specific apricot cultivars. They show the emergence of new (emergent) properties in the "genotype-environment" interaction system. The new scientific approaches being developed for the work of genetic and physiological systems of adaptability of each development phase make it possible to proceed to the creation of an innovative technology that ensures the maximum realization of the genetic potential of cultivars to the conditions of the growing environment using digital technologies.

The information obtained in the framework of research work is displayed, in which a non-local neural network was used in ASC-analysis (system-cognitive analysis) and the software tools provided for it an IS (intelligent system) called "Eidos", designed to resolve the whole complex tasks related to forecasting (identifying hybrids and cultivars present in the collection, recognition, typology, diagnostics) and determining the mutual relationships that exist between morphological traits (leaf shape and size, fruit shape, weight, size, index) in breeding for given traits. Detailed analytical work was carried out regarding the level of difference and similarity that determines genotypes. Class samples subjected to systematization by quantitative/qualitative assessment of the commonality of morphological traits associated with pear genotypes have been developed. Neurons of a non-local type were used to describe the severity of the relationship between the analyzed features of the genotypes inherent in a given culture. The formed model, based on the established signs of the morphological order, makes it possible to select and predict, under a specific horticultural system, both the “source” material for breeding for increased commercial and other significant criteria-criteria, and the typology of varieties for fruits of a specific size and shape.

The article presents the results of modeling the timing of flowering Armeniaca vulgaris Lam. based on the Krymsky Amur cultivar. To determine the estimated flowering date, a simple classical thermal model of external influence was chosen. The phases at the end of the formation of sporogenous tissue – meiosis, were used as a biological marker of the beginning of the vegetation of apricot cultivars and the exit of the plant from dormancy. The sum of thermal units required for the onset of the flowering phase is from 276.0°C to 352.8°C. The influence of air temperature in the spring period on the acceleration or deceleration of vegetation processes by 1-2 weeks was noted. The result of testing the model showed that it accurately describes the interannual variability of crop flowering dates. The discrepancy is no more than 2-4 days in 87% of cases.

The article presents the results of the research regarding the comparative assessment of modern blackberry cultivars. The studies were carried out for two years on a farm in the city of Semikarakorsk, Rostov region, Russia. Blackberry cultivars 'Ouachita', 'Natchez', 'Loch Tay', 'Heaven Can Wait', 'Black Gem' and 'Brzezina' were used as objects of study. As a result of the research, cultivars with the largest mass of fruits were identified: 'Black Gem' (11.4 g), 'Natchez' (13.3 g), 'Ouachita' (10.3 g). Productive cultivars are 'Loch Tay' (4.8 kg/bush), 'Black Gem' (4.2 kg/bush), 'Heaven Can Wait' (3.9 kg/bush), 'Ouachita' (3.8 kg/bush). Based on the combination of parameters and productivity recommended to use in industrial production varieties 'Ouachita', 'Heaven Can Wait', 'Loch Tay' and 'Black Gem'. Cultivars 'Brzezina' and 'Natchez' are suitable for growing in home gardens.

The article presents the results of research of apple trees genetic sources with a complex of economically valuable traits. In particular, high crop productivity, resistance to the II component of winter hardiness (temperature lowering up to -40°C in winter) and scab resistance for further breeding. In the conditions of epiphytotic 2022 vegetation period, the sixth scab race has spread in apple plantations of the Federal Scientific Center, as well as, presumably, in the Central Black Earth region. Due to the high ability of the Venturia inaequalis (Cooke) Wint. to combinational and mutational variability, there is a danger of reducing the resistance of apple genotypes to this disease. With the ongoing climate «anxiety», the probability of return of observed in the Central Black Earth region average long-term minimum conditions is not excluded. This factor remains limiting for the middle gardening zone. The resistance of apple trees to abiotic and biotic factors, including low temperatures and scab, may vary. This may affect plant productivity and, ultimately, the economic efficiency.

We studied the drought resistance of 43 forms of apricot of the Nikitsky Botanical Gardens’ breeding. Samples are divided into 3 groups: high drought resistance (16), middle (20), low (7). The high drought resistance had: 55 (water loss from 24 hour per % – 28.2), 84-694 (29.6%), 13/86 (29.9%), 8457 (30.0%), 99415 (30.8%), they can be usefull as source of drought resistant in breeding process. Three genotypes have increased water content in leaves – 8316 (68.1%), 10917 (70.6%), 84-949 (72.5%). The lowest indicators of water deficit were noted in five forms: 89-949 (2.6%), 432 (3.3%), 93-119 (3.6%), 99-354 (3.8%), 80 (3.9%). Mathematical processing by the method of cluster analysis and analysis of variance were carried out.

The problem of pollution of water spaces with heavy metals in Russia remains urgent with an increase in economic growth and production volumes at metallurgical enterprises. Plant agricultural waste can be used as sorbents for the extraction of heavy metal ions and oil products. The sorption properties of these materials are due to their chemical composition, namely the presence of lignin, cellulose and hemicellulose. Such vegetable waste includes almond shells, which remain in large quantities after processing almonds. Almond shell is a valuable biological resource and can be processed into a sorption material for wastewater treatment from heavy metal ions. This article discusses a method for obtaining sorption material from almond shells by chemical modification, and also determines its effectiveness in purifying a model solution containing copper ions.

The article presents the results of studying the characteristics of flowering of 22 cultivars and 10 hybrid forms of peach breeding from the Nikitsky Botanical Gardens according to the following criteria: degree, timing of the beginning, mass, end of flowering and its duration. 14 cultivars and forms with abundant flowering and four cultivars and forms with long flowering were noted. One form was distinguished by both a high degree and a long period of flowering. The selected cultivars and forms of peach are promising for use in the breeding process for breeding cultivars with a high degree of flowering and increased resistance to spring frosts. In cultivars, the trait showed the greatest stability (V = 13.9%) – the beginning of flowering, and the greatest variability (V = 21.4%) – the duration of flowering; in forms, the most stable trait was the degree of flowering (V = 7.7%), and the most variable (V = 19.4%) was the time of flowering.

The results of the study of the gene pool of the apple tree (Malus × domestica Borkh.) of the FSBSI NCFSCHVW for two genes Rvi6 and Rvi8 of resistance to scab (Venturia inaequalis (Cooke) Wint.) are presented. The purpose of the study is to form and replenish the identified collections based on the assessment of the genetic diversity of Malus to improve the efficiency of the apple breeding process. Research work was carried out in accordance with generally accepted programs and methods for studying cultivars of perennial fruit plants; molecular genetic research methods were used in the work. Based on the use of the SSR marker CH-Vf1 and the SCAR marker VfC, 6 cultivars carrying the Rvi6 gene of resistance to Venturia inaequalis (Cooke) Wint. were isolated. Carriers of two genes of resistance to scab Rvi6 and Rvi8, valuable for breeding, have been identified varieties with resistance to scab of domestic breeding: Maslovskoe, Pamyati Khitrovo, Spasskoe and American – Priscilla.

The article presents long-term data on three criteria for the productivity of figs (Ficus carica L.): number of fruits, average weight of fruits and yield. The studies were carried out on the basis of the collection plantations of figs of the Nikitsky Botanical Gardensthe National Scientific Center from 2019 to 2022. The objects of study are 37 promising cultivars and forms of figs from the collection of the NBG-NSC. As a control, 3 variety forms of different ripening periods were taken. On the basis of statistical data processing, the best samples of different ripening periods were identified for individual characteristics, as well as for a set of characteristics that significantly exceed the control forms: 1-2-2, Iyulsky, 3-3-4, 20-20. A brief agrobiological characteristic of the selected samples is given.

The article gives an assessment of promising forms of sweet cherries bred by the NBG-NSC according to the main economic and biological characteristics and resistance to stress factors. As a result of the study, promising genotypes were identified, in which a useful economic and biological trait was expressed to the greatest extent of its manifestation. Forms 303, 478 and 601 are distinguished by late flowering of plants. Three forms have been identified with early fruit ripening – 355, 478, 941. Promising forms have been identified that are not inferior to control cultivars in terms of fruit weight 294, 303, 444, 478, 601, 758, 837, 941 and 953. During artificial freezing, forms 303, 478 and 601 stood out in terms of stability. The genotypes 478, 601, 758 and 304 showed a high adaptive potential during the return frosts. Forms 303, 304, 601 and 953 have been identified with high field drought resistance. The highest resistance to monilia was shown by genotypes 303, 941, as well as 444 and 601. In terms of resistance to coccomycosis, the highest score was shown by breeding forms 294 and 601.

A significant achievement of the last decade has been new data on the biological role of many phytomicronutrients related to irreplaceable nutrition factors, among which plant antioxidants, especially polyphenolic substances, are of particular importance. The isolation of polyphenols from plant raw materials is of great practical importance, since a properly selected technological technique and the completeness of the extraction of natural compounds form the qualitative characteristics of phytoextracts. It is known that polyphenolic compounds of Juglans regia L., including tannins, phenolic acids, naphthoquinones, flavonoids, have high antioxidant activity. Numerous studies indicate the high biotechnological potential of walnut (Juglans regia L.) and its processed products, including septums, as a source of polyphenolic antioxidants. The resulting extract of polyphenols of Juglans regia L. septums is an opaque mass of dark brown color with a pronounced woody-herbaceous aroma, tart taste and a moisture content of 6.2%, characterized by a high content of total extractives (285.0±1.5) and polyphenolic substances (137.5±1.5) mg/100 g. The antioxidant activity of the polyphenols of the obtained extract in terms of gallic acid is 1220.0±23.5 mcg/ml of the extract. The resulting extract of polyphenols can be used as a functional ingredient for enriching beverages with polyphenolic antioxidants.

At present, within the framework of the modernization of agriculture, the renewal of the assortment of fruit crops is of particular importance. The article presents the results of a long-term comprehensive assessment of promising elite forms of pear and cherry. The issues of their winter hardiness in terms of second component and the ability to withstand adverse biotic environmental factors are considered. The study of commodityconsumer qualities of fruits was carried out. The studies in laboratory and field conditions according to generally accepted methodological recommendations were carried out. Pear ('1-08-10', '5-08-72', '13-08-34') and cherry ('№ 51') genotypes by high resistance to frost in the middle of winter (-38оС), the most common in the Central Black Earth region to diseases (scab, septoria blight, entomosporium leaf spot; cherry leaf spot, monilial fruit rot) and pests (pear louse; black cherry aphid), attractive appearance and taste of fruits of universal purpose were characterized. These elites are of considerable interest for cultivation in industrial plantations and home gardens in central Russia. In 2022 the pears elite form 13-08-34 was transferred to the State variety testing under the name 'Yamal'.

Ziziphus (cottony jujube or simply jujube) is a promising subtropical fruit crop for the Crimea and the southern regions of Russia. The biological characteristics of the culture make it possible to obtain regular harvests of dietary fruits with a wide variety of biologically active substances. The fruits are consumed fresh, and are also raw materials for various processed products. An analysis of the genetic resources of jujube in the Nikitsky Botanical Gardens was carried out and data on the species and varietal composition of the collection were presented. The jujube (Zizyphus jujubа Mill.) species is represented by 173 samples (cultivars and breeding forms of foreign and domestic breeding). The main directions of scientific work with this crop are indicated. As a result of breeding work with the crop, 4 cultivars (Koktebel, Tsukerkovy, Sinit, Yalita) are included in the State Register of Protected Breeding Achievements of Russia.

The results of studying the species composition of pathogens on stone crops in the Crimea are presented. 6 pathogens of fungal and 1 viral etiologyhave been recorded on sweet cherries and plums. The species composition differed depending on the growing area, and the degree of damage from the weather conditions of the growing season and the fungicides used. The development of diseases progressed after precipitation and an increase in the average daily temperature to 18-20°C and slowed down with the setting of dry and hot weather. The most severe disease degree was manifested in June after heavy precipitation, which exceeded the average annual norm by 3 times. With the setting of dry and hot weather in July and August, the development of diseases decreased from 30.0% (gray rot) to 50.0% (moniliosis). The use of fungicides restrained the development of diseases. On the plums, when using fungicides, the degree of damage was lower than on the control trees: Alternaria blight – by 2.7 times, brown patch –by 1.4 times, clasterosporiosis – by 1.5 times, powdery mildew – by 2.5 times, sooty mould – by 2.7 times. Similar results were obtained in sweet cherry orchards.

For 5 years, phytosanitary monitoring was carried out in the collections of fruit, berry and nut crops of the Donetsk Botanical Garden. 43 species of phytophagous invertebrates and 37 species of phytopathogenic fungi were registered. Nine species of phytophages (Aphis grossulariae, A.pomi, Brachycaudus cardui, Hyalopterus pruni, Pterochloroides persicae, Stephanitis pyri, Anthonomus pomorum, Sciaphobus squalidus, Cydiapo monella, Grapholita funebrana, Dasineura mali, Rhagoletis cerasi) and 10 fungi (Blumeriella jaapii, Monilinia laxa, M. fructigena, Ophiognomonia leptostyla, Podosphaera mors-uvae, Taphrina deformans, Venturia inaequalis, V. pirina, Verticillium albo-atrum, Wilsonomyces carpophilus) were characterized as particularly harmful species. The frequency of protective chemical measures in the growing areas has been reduced due to the high recreational load and legal restrictions due to the nature conservation status of the territory.

The article describes the results of the combined use of biological preparations, immunomodulators and fungicides to control the development of pear scab (pathogen – Fusicladium pirinum (Sib.) Fokl.) in the conditions of the Botanical Garden of Peter the Great (St. Petersburg). A scheme for the use of biopreparations, growth regulators and silicon-containing fertilizers to increase the resistance of Pyrus L. plants to the disease is proposed. The order of application of a complex of agrochemicals during the growing season, depending on the phase of plant development, was determined. A decrease in the development and spread of the disease on leaves and fruits was noted, as well as an increase in the intensity of growth processes after the treatment of trees with biofungicides and growth regulators. The proposed protection scheme helps to reduce toxic pressure on biotopes and meets the safety requirements for the main useful components of agrobiocenoses and the environment, and also provides a high-quality crop.

During 2020–2023 the soil nematode fauna in different agricultural lands of the Central, the SouthWestern and the South-Eastern regions of the Crimea was researched. The nematode complexes in the abandoned fruit, grape agrocenoses and in the fields of cereals and legumes were compared. The species diversity data and the species similarly in different nematode complexes were demonstrated. The Jaccard similarity index in studied plots is low (0.2–0.4). The least similarity of the species composition of nematode complexes (К = 0.2) was noted between the experimental plots in the cereal fields and in the abandoned gardens, vineyards, in the fields with legumes. The proportion of phytoparasites in the nematode complex in the abandoned fruit agrocenoses (uprooted and not uprooted) is 26-36%. In the long-abandoned gardens in the southeast of the Crimea (Sudaksky region) and in the central Crimea (Simferopolsky region) the phytoparasite and the vector of viral diseases (Longidorus elongates) was found. The dangerous invasive phytoparasiteXiphinema index was not found in studied plots.

The article presents the results of assessing the resistance of walnut to brown spotting (Marssonina juglandis (Lib.) Magn.). The objects of the study were 25 hybrid forms of breeding and introduction of the Nikitsky Botanical Gardens (NBG–NSC). The results showed that without chemical treatment, all trees are annually damaged by this disease. In the course of resistance studies, three groups of forms were identified (resistant, medium-resistant and weakly resistant). The main part (50%) of the studied forms turned out to be stable, which made it possible to recommend them for further breeding work when breeding resistant varieties of walnut to brown spotting. This will be most relevant in regions with a high concentration of precipitation in the first half of summer.

The article presents the results of assessing the self-fertility of apricot cultivars and forms in the mountainous conditions of Dagestan. It is shown that most of the samples of Dagestan origin (71%) are selfsterile and semi-sterile. There was a tendency towards an increase in the number of stamens and a flower index and a decrease in the length of the pistil from self-fertile to self-fertile cultivars. Flower index in self-fertile varieties averaged 1.39, semi-sterile – 1.67 and self-sterile – 1.88. An analysis of the correlation between the number of stamens and the length of the pistil showed a positive significant relationship for self-fertile cultivars (r = 0.50***), and unreliable for self-sterile and semi-sterile ones. Based on the results of a one-way analysis of variance, significant differences were established between all groups in terms of the morphological characteristics of the flower. Pairwise comparison using the Tukey test showed the smallest significant differences between sterile and semi-sterile samples.

For the first time, studies were carried out on the degree of ripening of peach and almond shoots in Central Russia. It is shown that histochemical indicators of wood maturation cannot serve as a reliable marker of selection for frost resistance. It was revealed that the most vulnerable links in the winter hardiness of peach and almonds are the frost resistance of xylem during autumn hardening and the frost resistance of flower buds after deep dormancy. 38 genotypes of peach and almonds were evaluated for frost resistance of flower buds and wood. A universal donor of frost resistance for almonds and peaches has been identified.

The yield of stone crops in the Southern Urals is mainly determined by favorable weather conditions during flowering and ovary growth. Significant damage to the crop is caused by recurrent frosts not so much in the flowering phase as in the ovary growth phase. A characteristic feature is the critical frosts at the end of May, damaging the young ovaries. The delay of the flowering phase in 2018 against the background of other years of observations by 10-20 days contributed to the fruiting of apricot (Prunus armeniaca L.) and increased yields of other sensitive crops, such as nanking cherry (P. tomentosa Thunb.). sand cherry (P. pumila L.) is characterized by relatively later flowering periods, and therefore the last critical frosts in some years fell at the beginning of flowering and did not significantly reduce the yield. Critical frosts during the flowering period do not lead to a complete or almost complete loss of harvest if they fall at the beginning or middle of the period. Later blooming flowers are able to provide partial fruiting. Therefore, not only the late start of flowering, but also an increase in the duration of flowering can provide a higher stable yield over the years.

The results of a phytochemical study of some biologically active substances (BAS) in the leaves of common apricot Prunus armeniaca L. (Rosaceae) specimens grown under equal conditions at the Tsudakhar experimental base of the Mountain Botanical Garden are presented. The maximum content of flavonoids was found in the leaves of the cultivar 'Aysberg' – 5.94%, and the cultivars 'Faraon' – 5.56% and 'Saratovskiyrubin' – 5.23%, as well as the Dagestan cultivar 'Khekobarsh' – 5.41%. The highest content of anthocyanins in the leaves is observed in the cultivar of Moscow selection 'Alesha' – 1.16%, as well as in the leaves of Dagestan cultivars – 'Khonobakh' (1.14%) and 'Khekobarsh' (1.07%).

The article presents the results of biochemical and pomological assessments of the fruits of hybrid forms of cherry plum breeding of the Nikitsky Botanical Gardens (NBG-NSC). As a result of research, the value of Prunus cerasifera Ehrh fruits has been shown for the human diet. Promising genotypes were selected based on the quantitative content of vitamin "C" and titrated acids, sugars, anthocyanins, pectins, solids, leucoanthocyanins, as well as forms with high commercial qualities of fruits. Studies of the chemical composition of fruits allowed us to identify the best breeding samples with a high content of biologically active substances that are of interest for inclusion in the breeding process and practical use. The genetic diversity of the collection genotypes allowed us to select a valuable form 99-18 (Olen'ka free pollination) with large fruits, cartilaginous flesh and good taste, approaching the content of dry substances, sugars and pectin to the samples from the Southern Coast of the Crimea.

In the arid conditions of the Central Ciscaucasia, for the rational use of available environmental resources and the formation of high yields of green and dry mass, it is advisable to study and use new cultivars of sweet sorghum (Sorghum saccuratum) of domestic breeding, which are distinguished by high rates of adaptability to growing conditions, productivity and profitable seed production. The objective of the research is to clarify the botanical characteristics of new cultivars of sugar sorghum, which increase the drought resistance and improve the fodder qualities of this crop. The research results testify to the high productivity of the new cultivars 'Tandem', 'Larets', as well as line 8611. The yield of the standard cultivar 'Silosnoye 88' for 2017-2020 averaged: green mass 57.1 t/ha; dry matter 15.5 t/ha. Among the studied new options, the highest productivity was obtained in samples 'Tandem' (respectively 61.2 and 16.1 t/ha), 'L.8611' (61.4 and 15.4 t/ha) and 'Larets' (58.9 and 15.2 t/ha). The highest content of sugars in the stem juice, according to the analysis of the quality of the green mass, was in the lines 'L.7897' and 'L.8611' and in the cultivar 'Tandem' (17.2-19.1%). For standard variants, this indicator had a value of 11.3-14.3%. The high foliage of plants depends on the number of leaves on the plant, as well as the width and length of the leaf. Based on the combination of these features, new variants 'Tandem', 'Casket' and 'L.8611' were distinguished. The most significant plant height in the phase of seed ripening had mid-late cultivars 'Larets' (238 cm), 'L. 8611' (247 cm) and mid-season cultivar 'Tandem' (259 cm). The studied numbers are aligned in height, have an upright bush shape, bushiness is weak.

The rationale for conducting scientific research is the need for innovative technologies in seed production that increase the yield of high-quality melon seeds. The use of growth stimulators in the technology of growing watermelon, as studies have shown, is one of the promising, less energy-intensive agrotechnical measures in growing gourds, increasing its yield and seed quality. Studies have established a high effect of the use of growth regulators on vegetative plants. Fruit yield increased by 34.5% and 27.6% compared to the control variant. The use of growth regulators in the technology of growing watermelon, the highest seed yield was obtained in the variant with the use of “Potassium Humate BP20” by 1.6 times and 39.1% more compared to the variant of plant treatment with water. The use of the growth regulator “Fitozont” with the treatment of plants during the growing season, the yield of seeds was 40.3% and 53.9% more compared to the control variant (treatment of plants during the growing season). The yield of original seeds was noted in the variant with the use of the growth regulator “Potassium Humate BP20” by 6.1% 9.2% more and the use of “Fitozont” preparation by 6.4%-10.0% more compared to the control treatment of plants with water during the growing season. A positive effect of growth stimulants on seed germination was also revealed, the maximum effect was obtained in variants with the use of “Potassium Humate” and “Fitozont” preparations with a double treatment of plants during the growing season 99-100%.