Fruit growing
and viticulture of South Russia
The studies were carried out according to the programs and methods of variety study and breeding generally accepted and developed at the FSBSI NCFSCHVW in the center for collective use Research and breeding collection of genetic resources of horticultural crops. The objects of research are 57 varieties and forms of apple trees (Malus × domestica Borkh.) of different ploidy, ecological geographic and genetic origin. The purpose of the study is to study allelic polymorphism for the self-incompatibility gene during pollination in representatives of the genus Malus Mill. for use in apple breeding. The CTAB method was used to prepare the DNA preparation. To identify alleles S2, S3, S5, S7 and S10 of the desired gene used the method of PCR analysis. It was revealed that these alleles of the S gene have a significant difference in the frequency of occurrence in the studied sample. The most common allele is S2, the frequency of which is the highest in the sample 40.35%; the frequency of occurrence of alleles S3, S5, S7 and S10 is significantly lower (in 1.94.6 times) and is 21.05 %; 8.77 %; 17.54 % and 21.05 %, respectively. Among scab-immune apple cultivars, the S2 and S10 alleles are the most common (distribution frequency 54.17 % and 33.33 %, respectively). According to the results of DNA analysis among 57 sample samples in 10 varieties: Victoria, Virginia, Gertrude, John Downey, Zheltozelenoe, Imperial Pavla, Ketney, Nikita, Riesling red, Florking did not reveal the presence of alleles S2, S3, S5, S7 and S10. With the exception of Victoria and Virginia varieties with low pollen viability, the remaining varieties are identified as promising pollinators (taking into account the timing and duration of the flowering period, the degree of pollen viability) for use in breeding and production. The results of the analysis of this sample of apple varieties are important for solving the problems of structuring the collection fund, replenishing information databases, identifying the best pollinators for breeding research and use in production.
Obtaining high-quality sweet cherry fruits in recent years correlates quite strongly with the degree of adaptability of cultivated varieties, which is determined by the weather and climatic factors of the region. The timing of the passage of the phenological stages of the seasonal development of sweet cherries and their duration in the moderate continental climate of southern Russia have been established. The types of stressors that occur during the period of intensive development of sweet cherry fruit organs and their influence on the productivity of varieties are described. The obtained data showed that the temperature during the development of fruit buds of sweet cherries can vary greatly, so in the phenophase dormant period of fruit buds it was within + 4.4 º (2020) + 2.3 º (2019), respectively and timing were different. Consequently, changes in the temperature regime affect the speed and rate of development of spring phenophases. Against the background of the action of weather stressors, groups of sweet cherry varieties were established, which are most susceptible to the influence of abiotic factors and react with a decrease in yield capacity. Thus, early varieties during the study period had lower productivity compared to medium and late varieties. Among all groups, varieties with stable fruiting even under conditions of stressors were distinguished Alaya, Anons, Dar izobiliya, Volshebnitsa. A correlation has been established between the yield capacity and the abiotic factors that affect its implementation (average monthly temperature during the dormant and flowering periods and the total precipitation in the same phenophases), as well as the temperature factor for the duration of the dormant and flowering periods. Regression analysis revealed the greatest relationship between factors such as yield capacity and average air temperature during the flowering period (R2 = 0.972), the temperature factor did not significantly affect the duration of the phenophases of the dormant and flowering periods (R2 = 0.004; R2 = 0.239, respectively).
The article considers the issue of studying the morphogenesis of generative buds of sweet cherry varieties in the conditions of the Kuban zone of the Krasnodar region, the influence of the temperature factor on the nature of the course of this process and the subsequent yield capacity of the studied plants. According to the literature data, in dry years, the laying of flower buds begins 2-3 weeks earlier than usual. At the same time, excessive drought delays or completely stops both the formation of buds and their differentiation. During the research period of 2021, the temperature that slows down the development of generative buds of stone fruit crops (more than 30 ºC) was observed throughout July and August, and in 2022 for the entire study period, reaching the category of a dangerous phenomenon in September. Periods of insufficient precipitation in 2021 were observed from the second decade of July to the first decade of August. In 2022, the growing season was drier than the previous one, which accelerated the differentiation of flower buds. The results of the analysis of the morphology of flower buds made it possible to identify varieties that are resistant to critical summer temperatures: Slavyanka, Romantika, Bigarro Oratovsky, Drogana Drogana zheltaya, Valery Chkalov, Kavkazskaya, Kosmicheskaya, Summit, Alaya, Volshebnitsa. The yield capacity of the studied sweet cherry varieties showed that stable fruiting was distinguished by: Kavkazskaya (average yield capacity was 17.5 kg/tree), Kavkazskaya uluchshennaya (20 kg/tree), Kosmicheskaya (22.5 kg/tree), Romantika (13.5 kg/tree), Drogana zheltaya (20.5 kg/ ree), Slavyanka (16.5 kg/tree), Summit (10 kg/tree). Varieties that give the highest yields in years with critically high temperatures can be recommended for cultivation in the conditions of southern horticulture, and they can serve as sources for breeding for heat resistance and productivity of cherry varieties.
In recent years, a tendency to increase the negative impact of low-temperature stressors in the winter and spring periods on walnut (Juglans regia L.) plants has been noted in the conditions of the North Caucasian region of southern Russia. The most dangerous is lowering the temperature to negative values during the growing season in the spring, since walnut trees are very vulnerable due t o recurrent spring frosts, even a slight decrease in air temperature can cause significant damage to plants. Just one frost event can lead to crop loss. With an increase in the temperature regime in the spring, the development of buds and the growth of annual shoots begin in the walnut, as a result of which their vulnerability to freezing is constantly increasing. The purpose of the study is to identify the most valuable genotypes for creating walnut varieties with increased resistance to cold stress, promising for cultivation in the south of Russia. Modern programs and methods of breeding and varietal study were used. The results of a long-term study (2019-2022) of walnut collection samples growing in the conditions of the North Caucasus region are presented. The study found that all hybrid forms are of Asian origin. Most damage from low temperatures was noted in hybrid seedlings from the family Ya-B-84. This fact is due to the seedlings obtained from the family Ya-B-84 and are second-generation hybrids from the Central Asian variety Bostanlyksky, while other hybrid families have Central Asian forms in the third and fourth generation. Thus, the low adaptability in the conditions of the North Caucasus in seedlings from the family Ya-B-84 is explained by the significant presence of the introduced germplasm in the origin. Hybrid walnut forms resistant to low-temperature stressors of the winter-spring period have been identified: 17-3-34, 17-3-41, 17-3-44, 17-2-20, 17-2-26, 17-2-30, 17-2-35, 17-2-41, 17-3-24, 17-3-27, 17-3-29, 17-3-30, 17-3-48, 17-3-12, 17- 3-16, 17-3-22, with a maximum degree of freezing in winter 1 point, in spring 2 points (when the temperature drops to -2.7 º C in the second decade of April 2020).
This article presents the results of varietal study for a five-year period (2018-2022) of a new table grape variety of interspecific cross Yangar bred by All-Russian Research Institute named after Ya. I. Potapenko for Viticulture and Winemaking Branch of Federal State Budget Scientific Institution FRARC. The studies were carried out on the vineyards of the Experimental Field of the ARRIV&W named after YA.I. Potapenko (Novocherkassk, Rostov region) according to generally accepted methods in viticulture, GOSTs and cultivation technology. Vineyards are non-covering, non-irrigated, grafted, rootstock Oppenheim 4 (SO 4). The vineyard planting scheme is 3.0 x 1.5 m, bush shape is palmet pruning on the middle stem, medium pruning. Based on the results of the study, data on agrobiological indicators, phenological bservations, productivity, chemical and technological characteristics of grape are provided, and an uvological assessment of fresh grapes is given. An ampelographic description of the grapevines is given, the main istinguishing morphological features are provided. Yangar belongs to varieties of early-medium ripening (the period from budbreak to ripeness of berries is 127 days), it ripens in the conditions of Novocherkassk at the end of August. The variety has very large bunches and berries (average weight 526 and 13.6 g, respectively), a high yield of commercial grapes, and a vineyard yield capacity of 14 t/ha. Yangar over the years of research has established itself as relatively resistant to major fungal diseases and downy mildew (at the level of 2.5-3.0 points on a five-point scale), with high winter hardiness and potential fruitfulness (84.6 % of breaking buds, of which 82.2 % of fruiting shoots). The new variety has relatively high sugar content in grape berries of 17.2 g/100 cm3 , low titratable acidity of 4.9 g/dm3 , and gluco-acidometric index of 3.5. The fault of this variety includes shedding of berries when the bushes are overloaded with a yield.