Elite varieties of black currant selected at the Federal Agrarian Scientific Centre of the North-East were studied with the purpose of identifying samples with an optimal combination of high productivity, large fruit, good taste, resistance to big bud mite and powdery mildew. The studies were carried out in 2015–2019 on a site located in the central agro-climatic zone of the Kirov region. 10 elite black currant varieties of 2013 planting were investigated. The varieties of Arkadiya and Vologda were used as control. The counts and observations were carried out using conventional methods. The combination of high productivity, its sustainability and high self-fertility was noted in varieties 71-2-07, 65-1-07 and 64-4-07. In terms of resistance to the pest, two highly resistant samples 71-2-07 and 65-1-07 were identified, which showed no signs of damage during the study period. The damage by big bud mite remained low across the entire experimental site. The average negative effect of big bud mite on the yield was found (r = -0.48). In the following 7 elite forms — 71-2-07, 65-1-07, 70-5-07, 46-1-07, 12-1-07, 15-1-07, 20-1-07 (70.0 % of the studied material), the maximum degree of damage by powdery mildew did not exceed 1.0 points, which indicates their high resistance. The combination of high resistance to big bud mites and resistance to powdery mildew was found in varieties 71-2-07 and 65-1-07. During the study period, 9 elite black currant varieties produced large-fruited berries. Out of these 9 forms, 3 (71-2-07, 64-4-07, 12-1-07) showed significantly higher values of this indicator compared to the Vologda control. Sample 27-1-07 was distinguished by a combination of large fruit, good taste and low acidity, as well as by high contents of ascorbic acid and dry matter. Sources of economically valuable traits were identified in 2 samples: 65-1-07 having a combination of high productivity, large fruit, high self-fertility, good taste, resistance to big bud mites and powdery mildew; 64-4-07 having a combination of high productivity, large fruit and high self-fertility. These genotypes can be recommended as a starting material for further breeding. On the basis of the results obtained, the Ariel variety (71-2-07) was forwarded to the State Variety Testing in 2020.

The article presents the results of estimation of adaptivity and productivity of 25 selected black currants hybrids under Bryansk region conditions. Tests have been done in 2019-2020 according to the common used programs and methods for breeding and variety testing of fruit and berries crops. The aim of the research was to evaluate the total plant state, flowering level, number of berries per a cluster, berries’ weight and productivity as well as to select the most adaptive and productive lines for their use in the future breeding work. Genotypes 8-20-227, 8-20-229 and 8-20-243 with excellent general condition and degree of flowering have been identified from the Yadrenaya x Izyumnaya family. In the formation of the overall crop, a significant place is occupied by such a component of productivity as the number of berries in the cluster. The level of manifestation of this trait is largely determined by the genetic basis of plants and significantly depends on the conditions of overwintering, the level of agricultural technology and weather conditions before and after flowering, as well as during the laying of generative buds. There are not lines with long clusters. There are some hybrids with moderate clusters (7-8 berries): 8-20-219 and 8-20-227 (Yadrenaya.Izyumnaya), 8-20-166, 8-20-185 and 8-20-177 (7-1-157.Litvinovskaya). The other lines had short clusters (5-6 berries) and very short ones (3-4 berries). The average berries’ weight was from 1.0 g (8-20-167) to 2.2 g (8-20-13). The seedlings 8-20-13 (7-2-229.Uslada) and 8-20-175 (7-1-157.Litvinovskaya) had the highest berries’ weight of 3.3 g and 3.1 g. Productivity of selected hybrid lines varied from 0.2 kg/bush (8-20-214 and 8-20-15) to 2.4 kg/bush (8-20-227). As a result of the studies carried out, genotypes 8-20-227, 8-20-229 and 8-20-223 from the Yadrenaya x Izyumnaya family, resistant to abiotic and biotic environmental factors with a productivity of 2.4, 2.2 and 2.2 kg / bush, respectively, were identified. These genotypes have been multiplied and will be further used in breeding as sources of high productivity.

Among the representatives of the Actinidia Lindl. genus, Actinidia kolomikta (Siebold et Zucc.) Planch. is valued as the most winter-hardy variety with high taste and dietary properties. The Federal Horticultural Research Centre for Breeding, Agrotechnology and Nursery has a live collection of Actinidia, which includes more than a hundred cultivated forms and varieties. In this study, ash content in Actinidia kolomikta fruits of 10 varieties and collection samples was studied by energy-dispersive X-ray spectroscopy using an analytical scanning electron microscope JEOL JSM6090 LA. A decreasing series was established for the accumulation of ash elements in the fruits of the studied samples: Ca> K> P> Mg> Mo> S> Se> Zn> Fe> Co> Si> Na. In terms of accumulation of useful macro- and micronutrients, the most valuable varieties were identified. The total accumulation of macronutrients in the fruit ash ranged from 28.6 to 45.3 wt%. This indicator was the highest in the fruits of Dolgovechnaya, Uslada and Vinogradnaya (42.068–45.638 wt%). The fruits of the Uslada variety were distinguished by a high content of phosphorus (5.89), silicon (0.504), sulfur (1.34) and potassium (23.596 wt%). In terms of micronutrient accumulation, the Pamyati Kolbasinoj variety (4.904 wt%) showed the highest levels of molybdenum (3.804) and selenium (0.801 wt%). Iron accumulated more readily in the fruits of the Uslada variety (0.161), cobalt — in Nadezhda (0.157), zinc — in Vinogradnaya (0.247) and Chempion (0.195). A statistically significant positive correlation (r > 0.7) was revealed in the accumulation of the following pairs of ash elements: sodium — sulfur (r = 0.70), phosphorus — potassium (r = 0.75), silicon — iron (r = 0.76), as well as molybdenum with phosphorus (r = 0.84), sulfur (r = 0.83) and potassium (r = 0.71). A statistically significant negative correlation was observed only for the accumulation of phosphorus and calcium (r = -0.71). According to the results, the fruits of the Actinidia kolomikta varieties under study can be an additional or alternative source of dietary minerals in functional food products.

The article is dedicated to the search for effective ways to regulate the functional state of tea plants under stress that ensure an increase in yield and its stability in varying climatic conditions, preserving and improving the quality of products (finished tea). The research was carried out during 2019-2020 on the basis of the Adygeya Branch of the Federal Research Centre “The Subtropical Scientific Centre of the Russian Academy of Sciences” on tea plants of the Kimyn variety population. It is shown that the winter period can be considered comfortable for the tea culture, while in the summer the plants regularly suffer hydrothermal stress. During the action of stress factors in the period of summer depression, in the pre-winter months (October-November), on variants with foliar treatments with innovative forms of fertilizers, there was a slight increase in bound water, active formation of proline and ascorbic acid in physiologically mature tea leaves. The use of innovative forms of fertilizers is an element of activation of the nonspecific protection mechanism and can become the main element of the technology of cultivation of tea plants.

Creation of new varieties that combine a complex of valuable traits, incl. the marketability and quality of fruits for updating the assortment of sweet cherry is an urgent direction of breeding research. The paper presents the results of a long-term work on the assessment of 12 varieties of sweet cherries of domestic and foreign breeding according to the main parameters of marketability and quality of fruits. The studies were carried out in 2015–2020 on the basis of the «Tsentralnoye» experimental production farm of the North Caucasian Federal Scientific Center of Horticulture, Viticulture, Winemaking. As a result of regional breeding and long-term variety study sweet cherry varieties of local breeding (Alaya, Volshebnitsa, Chernie glaza) and introduced varieties (Anonce, Vasilisa, Kroupnoplodnaya, Sweet Heart, Skina) with larger fruits (fruit weight of 8.5–12.0 g) were identified. These varieties correspond to world marketability standards. Varieties with high biochemical parameters have been revealed: vitamin C (10.9–13.0 mg/100 g) Volshebnitsa, Podarok leta, Anonce; vitamin P (81.6–116.0 mg/100 g) Volshebnitsa, Podarok leta, Kroupnoplodnaya; anthocyanins (213.5–390.0 mg/100 g) Madonna, Chernie glaza; sugars (14.2–15.2 %) Alaya, Volshebnitsa, Podarok leta; soluble solids (19.8–22.8 %) Alaya and Volshebnitsa. A greatest variation in parameters (Cv = 60 %) was noted in the number of anthocyanins from 87.0 in the Volshebnitsa variety to 390.0 mg/100 g in the Madonna variety. At the same time, the supposed direct correlation between the ripening period and the accumulation of sugars (R2 = 0.083) and dry matter (R2 = 0.107) was not revealed, due primarily to the varietal specifics and year conditions. For modern technologies of the production of high-quality cherry products in the south of the country, domestic varieties Krasnaya devitsa, Volshebnitsa, Alaya, introduced varieties Anonce, Kroupnoplodnaya, Sweet Heart and Skina, stably bearing fruit under stress conditions, with a yield of 20.0 t/ha with a planting scheme 5.3 m, high marketable and taste qualities were suggested. Super early ripening cherry variety Madonna was recommended to expand the regional cherry conveyor.

The aim was to obtain Japanese iris varieties with different flowering periods, original colour of flowers, good corrugation of petals and greater resistance to various adverse environmental factors in the south of Primorsky Krai, Russia. New varieties were created by spontaneous and directed hybridization of geographically distant varieties, selection of adaptability donors and involvement of radiation mutagenesis in the breeding process. Intervarietal hybrids were characterised by intermediate inheritance of colour and flower shape, generative and vegetative productivity, plant height and flowering time. The inclusion of hybrid forms in the breeding process allowed the variety of flower colour and shape, flowering time and generative productivity to be expanded in the F₂ generation. Promising interhybrid forms with biological characteristics that determine the possibility of their cultivation under the extreme conditions of the subregion were selected. A hybrid fund was created: over 135 adapted genotypes and 14 varieties. On the basis of the long-term experimental research, the expediency and necessity of breeding work with Japanese irises under the conditions of the subregion was established.

The results of a long-term ecological testing of 12 apple varieties of domestic and foreign selection in the Republic of North Ossetia-Alania are presented. The biological features of fruiting of representatives of the genus Malus in a southern region of Russia were studied with the purpose of identifying the most valuable varieties in terms of a set of indicators for further breeding and production. According to the conducted long-term observations (2012–2019), the following varieties with compact small-sized crowns (volume of 1.48-2.09 m³) were identified: Zolotaya Korona, Lyubimoe Dutovoj, Sunrise and Red Chiff. Among summer triploid varieties, the variety of Soyuz was selected according to the yield factor (total yield was 159.2 t/ha, which was 56.5 t/ha higher than the control). The varieties of early winter and winter ripening period with a high total (198.3–299.2 t/ha) and average (33.05–49.87 t/ha) yield were determined: Ligol, Zolotaya Korona, Lyubimoe Dutovoj, Alanskoe and Pinova. It was established that the varieties of Alanskoe, Zolotaya Korona, Lyubimoe Dutovoj, Sunrise and Pinova exhibit high productivity indicators, with the specific productivity of the crown volume being 17.00–21.87 kg/m³. It was revealed that the fruits of all studied foreign and domestic apple varieties grown under favourable conditions of the region meet modern requirements in terms of diameter (65–75 + mm) and average weight (200–220 g). Among the most promising varieties for breeding and production were found to be Liberty, Zolotaya Korona and Lyubimoe Dutovoj with large fruit (214.5–237.8 g), as well as Soyuz, Ligol, Alanskoe and Prikubanskoe with very large fruit (289.3–330.2 g). It is concluded that the apple varieties of regional selection (Alanskoe, Zolotaya Korona, Lyubimoe Dutovoj, Soyuz) and foreign selection (Sunrise and Pinova) can be recommended when breeding varieties with the required set of valuable agrobiological propertites, as well as when creating intensive industrial plantings and obtaining high-quality domestic fruit products.

In recent years, Russian gardeners have become interested in apple seed stocks, since they are indispensable for growing planting material of the highest quality categories for the purpose of setting up mother-cuttings, nurseries of clonal stocks and intensive orchards intended for obtaining organic products. The advantage of apple seed stocks is not only in a powerful root system and resistance to biotic and abiotic stressors, but also in the absence of a harmful viral infection from which almost all clonal stocks in Russia suffer. The opinion that trees are more vigorous on seed stocks, and orchards later enter in the fruiting period is erroneous, since there are developed technologies that make it possible the establishment of intensive apple tree plantations that enter the fruiting period 2 years after grafting. Among the apple clonal stocks, the intensively propagated form 54-118 is characterized by good anchoring and winter hardiness. Due to the lack of scientific data on the comparative study of seed and clonal stocks in the context of scion/stock combinations, we have begun a long-term study in order to identify the most promising of them in terms of early fruitfulness and high productivity. Long-term studies were carried out on the basis of the Orenburg branch of the Federal Horticultural Research Center for Breeding, Agrotechnology and Nursery from 2000 to 2020. The analysis of the results of the tests carried out shows that all the plantings on stocks 54-118 and 64-143 turned out to be early fruitfulness, and the stocks were suitable for intensive gardening, since the varieties grafted on them have a restrained growth force and a compact crown. The smallest height from 1.9 to 2.8 m was noted in trees on the 54-118 stock, on the 64-143 stock this parameter, depending on the variety, varied from 3.2 to 3.8 m. The largest crown diameter (over 3.0 m) and the largest projection area of the crown had plantings of all varieties on the seed stock of Purple Ranetka. The yield of apple tree plantations on stock 54-118 varied from 10.4 (Serebryanoe Kopitce variety) to 14.1 t/ha (Chudnoe variety), and revenue from the sale of products from 1 ha ranged from 263.1 to 356.7 thousand rubles. The highest profitability on clonal stock 54-118 was distinguished by perennial plantations of the Chudnoe variety (83.8 %). On stock 64-143, the yield of plantings varied from 10.2 t / ha (Serebryanoe Kopitce variety) to 13.5 t / ha (Chudnoe variety), the proceeds from the sale of products per hectare also varied from 258.1 thousand rubles. up to 341.5 thousand rubles. The highest profitability of production was noted in the plantations on the stock 64-143 of the variety Mechtatelnitsa (82.2 %). The average yield of apple varieties grafted on the seed stock of Purple Ranetka ranged from 8.2 (variety Letnee Polosatoe (K) to 9.3 t / ha (variety Serebryanoe Kopitce); high profitability of production was distinguished by plantings of the variety Mechtatelnitsa on ranetka purpurovaya (16.3 %).