Currently, the problem of ecological production is becoming more relevant. One of the ways to solve it is the use of varieties that combine high productivity with sufficient adaptability to environmental conditions, have high taste and commercial qualities of fruits, are resistant to diseases, and significantly affect fruit quality and yield. The purpose of the work is to identify the problem and determine directions in the creation of breeding material for cherries and sweet cherries resistant to coccomycosis based on a literature review. When performing the work, open sources were studied and used, containing information on the distribution, etiology of coccomycosis, methods of its infection and spread, the stability of the assortment of cherries approved for use in the Russian Federation, as well as electronic scientific libraries. It was revealed that the main problem of creating such an assortment of the subgenus Cerasus (Mill.) A. Gray is the ability of Blumeriella jaapii (Rehm) Arx to overcome the resistance of the host, which is determined by its reproductive and population characteristics. Resistance to B. jaapii in the breeding material of the subgenus under study usually dominates and is controlled mono-, oligo-, and polygenic. It can be obtained with the involvement of donors of resistance to cocomycosis (13 species) in the selection process. Modern varieties and forms were created with the participation of a donor – Prunus maackii Rupr. and P. lannesiana (Carr) E. H. Wilson. The use of genetic methods in the work on the creation of breeding material of the subgenus Cerasus with resistance to coccomycosis will allow its intensification due to more accurate selection of forms with this trait.F

This article presents the results of studies of the biochemical composition of raspberry varieties (Rubus idaeus L.) cultivated in the Orenburg region. The research was carried out on the collection plots of raspberries of the Orenburg branch of the Federal State Budgetary Research Center of Horticulture 2005-2021. The high content of soluble solids in summer raspberries, compared with the control variety Rannii Syurpriz (12.17-15.21 %), had the varieties Samarskaya Plotnaya, Juravlik, Solnishko and on average exceeded by 3.6-5.8 %, and in raspberries of the repair type of fruiting, the highest value of this indicator was noted in varieties Oranjevoe Chudo (10.7-13.0 %) and Arisha (11.4-12.8 %). The coefficient of variation is 11-16 %. On average, the sugar content in the fruits of raspberry varieties varied from 5.9 to 8.5 %, with the largest amount in the fruits of the varieties Rannii Syurpriz (K) (8.5 %), Juravlik (8.2 %) and Solnishko (8.1 %). These varieties had the most balanced taste due to the low acid content. The maximum content of titrated acid in fruits was 2.0 % in Samarskaya Plotnaya varieties and 2.1 % in Rubinovoe Ojerele varieties. Over many years of research, it has been revealed that the content of ascorbic acid in summer raspberries averaged 24.9 (Volnica) – 51.1 (Skromnica) mg/100 g, and in raspberries of the primocane raspberry of fruiting 40.0 (Jar-Ptica) – 45.5 (Gerakl) mg/100 g. A higher content of ascorbic acid in the fruits of summer raspberries, compared with the control variety Rannii Syurpriz (36.19-45.14 mg/100 g), were characterized by the varieties Skromnica (44.68-58.3 mg/100 g), Samarskaya Plotnaya (39.04-60.48 mg/100 g), Blestyaschaya (35.16-61.32 mg/100 g), Juravlik (33.37-56.90 mg/100 g). The highest content of ascorbic acid in the fruits of raspberries of the repair type of fruiting was found in the varieties Gerakl (41.3-49.6 mg/100 g) and Arisha (40.5-47.3 mg/100 g) in comparison with the control variety Jar-Ptica (35.3-44.7 mg/100 g). Thus, varieties have been selected from the genetic collection of raspberries according to a complex of biochemical characteristics for use in the breeding process: Jar-Ptica, Juravlik, Arisha.

Studies on the frost resistance of cherry plum were carried out in 2022-2023 at the Federal Horticultural Research Center for Breeding, Agrotechnology and Nursery in laboratory conditions by artificial freezing in the climatic chamber EW 1070. The objects of research were plants of the varieties Shatyor, Zlato Skifov and Kubanskaya Kometa, own-rooted and grafted on clone rootstocks SVG-11-19 and 13-113. The purpose of the research is to study the influence of the method of reproduction and the shape of the rootstock on the frost resistance of buds and tissues of annual branches of cherry plum and to identify the most frost-resistant graft-rootstock combinations. It was found that after freezing at t = -30 °C, more than 50 % of generative rudiments remained viable in both years of research in the Kubanskaya Kometa variety, in the Zlato Skifov variety – from 30 to 45 %, in the Shatyor variety – on average 49 %. The limits of changes in the frost resistance of generative buds of varieties depending on the rootstock are shown: in the Kubanskaya Kometa variety – from 46,5 % (13-113) to 68,9 % (SVG-11-19), in the Zlato Skifov variety – from 37,6 % (own-rooted) to 45,3 % (SVG-11-19), and in the variety Shatyor – from 41,4 % (roots) to 45,3 % (SVG-11-19). When using the clone rootstock SVG-11-19, the safety of generative rudiments increased by 17 % compared to the root variant. Damage to vegetative buds and tissues of annual branches up to 1-3 points was caused by temperature t = -35 °C. The most frost-resistant combinations were the Kubanskaya Kometa/SVG-11-19 and the Shatyor/SVG-11- 19, in which kidney and tissue damage was less than 1 point.

The article presents the results of an analytical review of Russian and foreign literature sources devoted to the study of the influence of the composition and functions of phenolic compounds in apple fruits on their quality indicators (appearance, pulp density, nutritional value). Studies of the biochemical composition of apple fruits are currently relevant and are being carried out with the aim of in-depth study of the assortment of fruit crops and assessment of its potential use in breeding to increase the content of biologically active compounds. The prospects of the search for plants that accumulate phenolic compounds in tissues, which have a protective antioxidant function and nutritional value, have been confirmed. The issue of the role of accumulation, the dynamics of the content of individual phenolic compounds and the total content of phenolic compounds in various metabolic processes that determine the properties of apple fruits is considered. Analysis of the results of thematic scientific works on changes in the composition and content of phenolic compounds will allow targeted research leading to the use of fruits as a potential source of phenolic compounds, as well as identifying sources of accumulation of biologically active substances for practical use in breeding. The creation of new varieties of apple trees is necessary to obtain useful secondary phenolic metabolites contained in fruits, while the range of use of fruits includes the production of processed products. The expediency of carrying out breeding work aimed at increasing the content of phenolic compounds in fruits is confirmed by a number of recent publications by Russian and foreign scientists.

The article presents the results of a comprehensive introduction study of 18 cultivars of tubular narcissus from the collection of the Cheboksary Branch of the MBG RAS in 2016-2022 in order to select cultivars of value for production. The study of narcissus cultivars was carried out according to the classical methods of the Main Botanical Garden of the Russian Academy of Sciences. The assessment of decorative and economic and biological features on a 150-point scale in the soil and climatic conditions of the Middle Volga region was carried out. The potential possibilities of cultivars for use in green construction are investigated. In the comparative assessment, the main attention was paid to the decorative qualities of cultivars and their general adaptability to local conditions. The studied cultivars are divided into groups according to the flowering period. 8 cultivars of tubular narcissus bloom early (19.IV-2.V), 10 cultivars – in the middle (30.IV-11.V). The total flowering period is 30 days. The duration of flowering of introductions varies from 7-12 days (in the ‘Stentor’ cultivar) to 17-21 days (the ‘Arctic Gold’ cultivar). The decorative qualities of the cultivars were determined by the following indicators: aroma, originality, plant condition, duration and productivity of flowering, strength and length of the peduncle, size, color, shape of the flower. Assessment of tubular narcissus on a 100-point scale revealed a high degree of decorativeness in 8 cultivars with a total score of at least 90: ‘Soiree’ (92 points), ‘White Triumphator’ (93), ‘Point Barrow’ (94), ‘Grape Fruit’ (94), ‘Mount Hood’ (97), ‘Dutch Master’ (97), ‘Spellbinder’ (98), ‘Beersheba’ (98). When studying the economic and biological qualities of cultivars, the reproduction coefficient, damage by diseases and pests, general resistance to adverse conditions were taken into account. According to the methodology, the maximum score for economic and biological characteristics is 50 points. 15 collectible cultivars received high marks – in total more than 40 points. According to the complex of decorative and economic and biological features, the most valuable cultivars for introduction into the zonal assortment are cultivars with complex ratings of at least 140 points: ‘Beersheba’, ‘ Dutch Master’, ‘Grape Fruit’, ‘Mount Hood’, ‘Point Barrow’, ‘Soiree’, ‘Spellbinder’, ‘White Triumphator’. These promising, decorative, with high adaptive potential cultivars of tubular narcissus are recommended for industrial cultivation and landscaping in the conditions of the Middle Volga region.

The article presents the results of assessing the decorative qualities of plants of the genus Pennisetum Rich. in the collection of the AB BGI FEB RAS. The studied cultivars showed differences in plant height and ear length. The height and size of the inflorescences directly depend on the meteorological conditions prevailing during the years of growing plants. The highest quantitative indicators of plant height were noted in the varieties 'Majestic Purple' and 'Purple Candles'. 'Purple Majesty' plants grow taller in containers than outdoors. The color of the vegetative parts of plants and inflorescences declared by the manufacturer for six varieties of Pennisetum glaucum L. did not correspond to the variety description. Variety 'Jade Princess', in comparison with other varieties, has a bright yellowish-green color of the leaves and burgundy-brown color of the inflorescences. In cultivar P. glaucum «Majestic Violet», splitting of varietal traits was observed in terms of the color of the vegetative parts of plants and the ear. The total duration of vegetation for all varieties of P. glaucum ranged from 189 to 211 days. Plant height in Pennisetum orientale Rich. regardless of the method of cultivation (open/ closed ground) varied insignificantly. The earliest flowering phase in outdoor cultivation was Pennisetum villosum Fresen. Pennisetum alopecuroides (L.) Spreng. late entry into the heading and flowering phase was noted, regardless of the method of cultivation. The highest quantitative indicators (plant height/ear length) among the studied species were found in Pennisetum setauceum (Forssk.) Chiov. According to the research results, P. setauceum and P. villosum can be attributed to the number of promising species for growing in the conditions of the south of the Amur Region. These species go through all phases of development and form full-fledged seeds; when grown in a container culture, they do not lose their decorative effect throughout the season.

The modern system of nursery management of strawberry should be aimed at the use of adaptive cultivars and clones, allowing to obtain high yields of high-quality products. Optimization of mineral nutrition of plants, the use of plant growth regulators are necessary for the modern management of plant repositories, including strawberry. The study of ways to increase the yield of planting material of strawberry due to the simultaneous inhibition of the formation of peduncles is an urgent task in uterine plantings of the highest quality categories. The purpose of the research: to study the effectiveness of ways to reduce the components of generative productivity and increase the yield of planting material of strawberry garden varieties of short daylight hours and neutral daylight hours. In a field agrochemical experiment with plant growth regulators and doses of nitrogen fertilizer in the Stupinsky district of the Moscow region, on sod-podzolic soils, strawberry cv. Lubava, Tsaritsa, Nashe Podmoscov’e, Polka were studied. Doses of nitrogen fertilizer: N = 80 kg/ha and 120 kg/ha. Plant growth regulators: chlormequat chloride and gibberellic acid (GC3). As a result of the first year of research, it was found that the use of plant growth regulators and an increased dose of nitrogen in the strawberry cultivar of neutral day (Lyubava) contributed to a decrease in generative productivity, but also caused a decrease in the number of outlets. In shortday strawberry plants, a cultivar-specific reaction to fertilizer doses and plant growth regulators was observed, as a result of which it was revealed that the nitrogen dose N 80 kg /ha contributes to an increase in the generative productivity of plants cv. Nashe Podmoskov’e to a greater extent than cv. Polka and cv.Tsaritsa.