Raspberries are among the most popular berries on the market; therefore, interest in this crop is constantly growing. Raspberries are cultivated in more than 50 countries around the world, and this number is increasing. The steady expansion of raspberry cultivation and yields is due to the scientific support of the industry with new cultivation technologies and varieties. The present study was aimed at revealing difficulties and problems in raspberry breeding and identifying current tendencies and development trends. The paper provides a brief overview of raspberry production in the world, as well as an analysis of active breeding programs in Russia and abroad. The features of the breeding tasks are considered depending on the regions of cultivation. The main problems, methods used, source materials and breeding achievements are presented. It is revealed that the overall purpose of breeding programs is to obtain productive varieties with high adaptation to abiotic and biotic stressors, suitable for various cultivation technologies and having excellent fruit quality. It was found that despite the successes achieved in raspberry breeding, at present there is still lack of varieties with high adaptation to the environment and very early or late-ripening varieties, allowing to extend the period of consumption of fresh berries, as well as lack of high-tech industrial varieties suitable for contemporary cultivation technologies, and varieties with required commodity and consumer properties. The prospects of raspberry breeding for the coming years are considered. It is shown that in order to achieve the strategic objectives in breeding, it is necessary to enrich the cultivated gene pool of raspberry with new inclusions of wild species of Rubus. This requires the cooperation and coordination of all breeding programs for the expansion and exchange of genetic resources. In order to accelerate the breeding process, it is necessary to actively use a large set of biotechnological methods tested and well-proven on berry crops. Wider use of molecular-genetic methods is essential to significantly increase the speed and accuracy of breeding.

Thus far, the world’s blackcurrant range comprises about 1,200 varieties and is constantly being improved. The most successful breeding programs for black currant have been implemented in Poland, England, Belarus, Ukraine, Sweden, Lithuania, Finland, Romania, China and Russia. However, the climatic conditions of several regions of the Russian Federation make it difficult to fully realize the biological potential of foreign varieties and they often do not correspond to the characteristics declared by the breeder. The study is aimed at making comprehensive assessment of the introducers to establish their selection potential and the possibility of industrial cultivation. The study was conducted in 2018-2021 in the black currant collection site of the Kokino station of Federal Horticultural Center for Breeding, Agrotechnology and Nursery (Bryansk region). 20 varieties of black currant of foreign breeding from different ecological and geographical groups were explored. A new local variety Kudesnik with average maturation time was taken for comparison. It was included in the State Register for Selection Achievements in 2022. An assessment of introduced black currant varieties by morphological character of plants revealed the features of their growth in the south-western conditions of the central Non-Black Earth region. Varieties that do not meet the requirements of modern intensive mechanized technologies have been established. In terms of plant height, the varieties Mriya, Nympha, Kupalinka, Cheryshneva, Amethyst, Sofiyivska and Triton do not meet the parameters appropriate for mechanical harvesting. It will be difficult to use berry harvesting equipment with the varieties Sofievskaya, Amethyst and Klussonovskaya due to the wide base of their bushes (>0.3 m). The varieties Sofievskaya and Klussonovskaya, with the highest yield (10 t/ha) do not meet the requirements of modern production in terms of bush mien and berries tearaway force. The best introducers (Sofievskaya, Klussonovskaya, Nympha, Mriya, Cheryshneva, Triton, Belorusochka, Kupalinka) with a yield of 8.3-10.0 tonnes/ha can be recommended for home gardening. A number of foreign varieties as genetic sources in breeding for berry strength (Cheryshneva, Ben Hope, Black Magic, Tiben); fruit size (Nympha); number of fruits in the claster (Triton, Cheryshneva); taste qualities (Mriya); high content of soluble solids (Ben Tirran, Sofievskaya, Mriya) and other characteristics of interest have been identified.

Despite the global trend of the increase in average annual air temperatures observed in recent years, the recurrence of stressful negative temperatures in winter has increased in the southern region of the Russian Federation, and, therefore, the problems of grape frost resistance remain relevant. Low-temperature stresses lead to serious damage and a decrease in vine yields. In order to distinguish the most resistant grape varieties, it is necessary to carry out plant research on the physiological and biochemical level. The paper presents the results of research related to the study of resistance to low negative temperatures of grape varieties of different ecological and geographical groups according to the activity of peroxidase enzyme and its isoforms. The research objects were grape varieties (interspecific hybrids) of European-American origin – Dostoyny, Krasnostop AZOS, Vostorg; of Western European origin – Aligote; of Eastern European origin – Zarif; of Euro-Amur-American origin – Kristall. The study was aimed at exploring the activity of peroxidase and its isoforms and, based on the research results, identifying grape varieties most resistant to low temperatures under the conditions of the southern region of Russia. According to the obtained data on peroxidase activity and electrophoretic separation of peroxidases in polyacrylamide gel, most resistant and less resistant grape varieties to low negative temperatures were identified. The resistant varieties Kristall, Krasnostop AZOS, Vostorg were characterized by a weak increase in peroxidase activity during autumn-winter period (1.1-1.4 times), higher number of isoforms, and their qualitative composition. The less resistant grape varieties Dostoyny, Aligote, and Zarif were characterized by a greater increase in peroxidase activity (1.7- 2.4 times), a small number of isoforms, and their disappearance under conditions of artificial stress. Based on the results, it can be concluded that the study of peroxidase activity and changes in isoperoxidase spectrum in grapevine shoots can be used as diagnostic criteria for assessment of grape varieties for their resistance to low negative temperatures in winter period.

Small-fruited citrus such as Fortunella Sw are becoming popular among a large variety of citrus fruits. Resistance, repeat flowering capacity, abundant fruiting combined with dwarfness, as well as the nutritional value of the fruits promote the use of the plants in hybridization to create new genotypes. The paper presents the quality characteristics of fruits of small-fruited hybrid forms derived from interspecific hybridization with Fortunella Margarita as the mother plant. The objects of the study were five promising forms: 202; 78; 90-3; Kip-14, Kalamondin-1, bred from interspecific hybridization under the auspices of the FRC SSC RAS. A brief pomological description of the size of the fruits and the juice extraction is presented in the paper. Moreover, two promising forms were established: 78 and 202. Kip-14 was distinguished by the smallest fruits with a mass of about 6.8 g and a thin skin. The study of the chemical composition of small-fruited hybrids showed that they were rich in vitamins, sugars and acids. In terms of quantity, sucrose predominates; its greatest amount was identified in the forms of Kalamondin-1 (38.09 g/kg), 78 (36.94 g/kg) and 202 (35.30 g/kg). It was revealed that in terms of sugar content, all hybrids were inferior to the original mother plant. 78 and Kip-14 were characterized by high content of soluble solids – more than 17%. 8 organic acids were identified in the fruits of the hybrids. Among the main organic acids, citric acid was dominant, the hybrid 202 – 6.53 g/100 g was indicated with high values of it. Kalamondin-1 had the highest amount of malic, succinic, acetic, lactic and oxalic acids. In terms of ascorbic acid, the hybrid Kip-14 was the leader (37.23 mg/100 g), and the fruits of this form were rich in sorbic acid (0.005 g/100 g). The largest amount of lactic acid (0.10 g/100 g) was observed in 90-3 hybrid. Fruits of 202 and Kip-14 did not contain oxalic acid.

In 2018-2020, the study was carried out in the Leninsky municipality of Moscow region to explore garden plum in terms of its growth, productivity and morphobiochemical processes depending on the stock. Planting was in 5×2.5 m plots. The subjects of the study include trees of 2 plum varieties (Yaichnaya Sinyaya and Utro) with 5 stocks: plum seedling stock (control), Novinka, OP-23-23, OPA-15-2 and 140-1. The trees were 18 years of age. The influence of the stock on the leaf morphology, biochemical indicators, growth and productivity of grafted plum trees was established. An increase in the linear and radial growth of trees in comparison with the control was noted on clonal stocks OPA-15-2 and OP-23-23, a decrease in height by 15-20% – on 140-1 and Novinka stocks. The minimal average length of shoots was identified for trees grafted on the 140-1 and Novinka (9-12 cm) stocks. When grafted on OPA-15-2 and OP-23-23 stocks, the total shoot growth was 1.7 times greater than on the seedling stock. The leaf area ranged from 21.4 (Yaichnaya Sinyaya/seedling stock) to 36.2 m2/tree. (Utro/OPA-15-2). Th e low-growing tree stock 140-1 produced a smaller assimilation apparatus than in the control. The leaf area index ranged from 4.3 to 7.2. The OPA-15-2 and OP-23-23 clonal stocks provided the optimal values of the leaf biometric indicators. The study of leaf microsculpture revealed the morphological differences depending on the stock for total number of stomata and their size. The stomatal index ranged from 1.7 to 2.0. The influence of stock on the content of photosynthetic pigments and their ratio was established by means of spectrophotometry. An increase in the content of the sum of chlorophylls (a + b) to 8.3 mg/ml and their highest ratio was observed in the leaves of the Utro/OPA- 15-2 and Yaichnaya Sinyaya/OP-23-23 combinations. The maximum values of antioxidant activity (over 90%) and content of phenolic compounds in leaves were recorded with OP-23-23 stock. Gas chromatography-mass spectrometry revealed quantitative differences in the composition of low-molecular metabolites (glycerol, myo-inositol, fumaric-, quinic- and lactic acids) depending on the stock. The productivity of garden plum varieties was 1.4-1.9 times higher when grafted with OPA-15-2, Novinka and OP-23-23 in comparison with seedling stock. Cultivation of the Yaichnaya Sinyaya variety with these stocks resulted in an increase in yield from 8 to 15 tonnes/ha, and cultivation of the Utro variety – from 12 to 18 tonnes/ha.

The woolly whitefly (Aleurothrixus floccosus Maskell), a species of neotropical origin, is a new pest of mandarin orange in Abkhazia. The invasive range of the species has been developing since 1959 and now covers Europe, North America, Africa, the Middle East and East Asia. It was recorded in Abkhazia in spring, 2017. The studies were conducted in 2016-2021 in all regions of Abkhazia by means of standard methods. According to the six-year study of the distribution and development of the phytophage population in the territory of Abkhazia, the species has dramatically increased in number and spread throughout all regions of the country. The identification of the pest was carried out in 2020, but the vector of its penetration into Abkhazia is yet to be clarified. Most likely, A. floccosus was introduced in Abkhazia with planting material of citrus crops. The first colonies of woolly whitefly are recorded in late May-June, followed by a rapid growth of the pest population. The development of the colony reaches its maximum by September, with a density of imago and nymphs of 102.2-152.3 units/leaf. The bioefficacy of different chemical insecticides was evaluated: organophosphorus compounds (Bi-58 Top, KE, with dimethoate as an active ingredient, consumption rate of 2 l/ha), neonicotinoids (Confidor Extra, VDG, active ingredient: imidacloprid, consumption rate of 0.4 kg/ha and Gazelle, RP, active ingredient: acetamipride, consumption rate of 0.15 and 0.5 kg/ha), chitin synthesis inhibitors (Applaud, SP, active ingredient: buprofezin, consumption rate of 0.5 and 1.0 kg/ha). Trials were set in August-September. Treatment of plants was carried out in triplicate against the background of treatment with Product 30 Plus, MME (petroleum jelly oil), the consumption rate of 30 l/ha in the third part of February. At the beginning of the trial, one leaf of mandarin, on average, had 80.2-89.4 whiteflies. From mid-August till the end of September, the number of whitefly colonies increased 1.52 times in control. The use of the insecticide Confidor Extra, WDG, 0.4 kg/ha and variants with increased rates of consumption of insecticides Apploud, SP, 1.0 kg/ha and Gazelle, RP, 0.5 kg/ha (triple treatment) appeared to be the most effective with the biological efficiency of 80.0, 86.7 and 85.8 %, respectively. Dimethoate-based organophosphorus insecticide, traditionally used in agrocenoses of citrus crops, showed insufficient effectiveness (70.0 %).

An economic and statistical assessment of the stability of agroecosystems with grape agrocenoses is given on the example of economic entities of the Krasnodar Krai with a calculated justification of integral indicators of the system-wide stability of agroecosystems and an analysis of the dynamics of their condition. The main elements of grape agrocenosis, in which bio-resource deformations are most manifested, were determined as follows: biocenosis, soil and soil microbiota, pathocenosis. Functional areas of bio-resource deformations in grape agrocenoses were revealed. Negative manifestations of chemical and technogenic intensifi cation were determined as leading to bio-resource deformation, namely: decreased pathogen sensitivity to chemical preparations used; complex negative consequences of increasing technogenic load; decreased immune status of plants. The above effects determine a general decrease in crop capacity and potential productivity. The share of influence of the factors on bio-resource deformations of grape agrocenoses and production efficiency was substantiated. The levels of reduction of eff ectiveness and stability of reproductive processes as a result of negative manifestation of bio-resource deformations in viticultural agrocenoses were identified as disturbances in reproductive processes and rationality of nature management. The priority role of biotechnologies based on molecular biology and biochemistry was determined as increasing the stability of grape agrocenoses, decreasing the chemical and technogenic load on agroecosystems, leveling the negative manifestations caused by these effects, and ensuring optimal technological and economic efficiency. The algorithm for formation and application of digital technologies for leveling the functional imbalances in the organization of reproductive processes caused by the negative influence of external (natural) environment factors is proposed, including: formation of multifunctional bases and data banks by the elements of viticulture system; formation of digital applications and an empirical database; identification of functional areas of bio-resource deformations; cognitive modeling of systemic relationships that determine the influence of chemical and technological processes on the bio-resource potential* (hereditary ability of a cultivated plant in all its life manifestations, levels and properties of its organization to reproduce a certain amount of production of a certain quality under specific soil, climate and technogenic conditions); development of a system architecture for a prototype of software and selection of programming language, validation and verification of models of digital technologies for bio-resource potential management; determination of optimal parameters for realization of bio-resource potential and ecological and economic sustainability of agro-ecosystems involving grape agrocenoses. The paper presents a technological and economic assessment of the use of digital technologies in ensuring the sustainability of grape agrocenoses and achieving optimal parameters of biotechnological processes.