Fruit growing
and viticulture of South Russia
In the southern regions of Russia, during the active growing season of pears, almost every year there is an impact of drought, heat, dry winds, which affects their water status, growth, productivity and adaptation. When selecting varieties for optimal placement, it is necessary to take into account their adaptability to dry growing conditions. From the collections of the Maykop experimental station VIR, more than 120 samples of pears were included in experiments to study the drought resistance of plants: 59 varieties, including 43 varieties of European origin and 16 East Asian, 26 species, 38 ecological forms of the Caucasian pear. Field assessment of the plant condition was carried out visually after prolonged exposure to stress. In parallel, a laboratory method of leaf wilting was used, which allows judging the degree of endurance of various samples to the dehydration factor and the relative drought resistance of plants by the parameters of the water regime. On the basis of adaptability and indicators of the water regime, pear samples with increased resistance of leaves to dehydration are identified, which can be recommended for cultivation in the foothill zone of the Republic of Adygea in areas with limited water supply. These are such European varieties as Bessemyanka, Borup, Williams, Krasnodarskaya letnyaya and Lastochka, whose leaves lost only 30-40 % of water in 6 hours of dehydration. Under the same conditions, the lowest water losses 42-46%) were observed in the varieties Minueli, Olga and Pinli from East Asian pears. From the MES VIR species collection, P. caucasica Fed., P. elaeagnifolia Pall., P. nivalis Jacq., P. salicifolia Pall., P. ussuriensis Maxim. may be of interest for breeding for drought resistance.
Modification changes in the phenotype and the norm of reaction in the technical grape variety Vydvizhenec under the influence of natural conditions against the background of traditional and biological ways of soil management have been established. The studies were carried out in the agro-ecological conditions of the moderate continental climate of the south of Russia using modern methods of field research. The average annual air temperature at the research site was 9.7 ºC. During the growing season (May-September) the temperature was 19.9 º, during the period of active growth of grape berries (II. June-III. August) 22.5 º, the maximum rose to plus 39.3 º, the minimum in the wintering period of grapes dropped to minus 26.7 º. The annual temperature range was 54.2 ºC. The drop in air temperature within the day during the growing season was 10.7 degrees Celsius, the maximum 17.7 º. The annual amount of atmospheric precipitation varied from 433 to 866 mm, with a norm of 620 mm. Variations in weather conditions were accompanied by modification variability in the number of clusters, average cluster weight, and grape yield. According to the correlation analysis, the strongest influence was exerted by the minimum air temperature (January-February) on the number of clusters (r = 0.640.41) and the average cluster mass (r = -0.67-0.52), the average temperature in the previous year by the number of clusters (r = 0.650.41), the average annual temperature per cluster weight (r = -0.47-0.35). Atmospheric precipitation as a whole for the year influenced the mass of the cluster (r = -0.38-0.30). The influence of weather conditions on the grape yield was weak. The reaction norm of the number of clusters was equal 23 against the background of black fallow, 25 natural grassing-down and 30 pcs/bush sowing of sour dock, the average weight of the cluster, respectively, 129, 90 and 103 g, the grape yield 5.79; 5,52 and 6,00 kg/bush.
Among a number of natural factors that ensure the development of the grapevine and predetermine the quality of wine, the soil belongs to one of the first places, since the soil for the grape plant is an important part of the habitat. The type of soil on which the vineyard grows, as well as its soil-forming rock, enriched with primary minerals and a large number of trace elements, are important. The soil contributes such substances to the plant, which have a particular impact on the quality and individual characteristics of the products obtained from grapes. The soil determines the fullness, finesse and bouquet, and often the type of wine itself. The winemaker only assists in the smooth flow of the process and the identification of those qualities which are already present in the must. The research objects were the must and the wines from the grape variety Flower, grown on the following types of soils: carbonate chernozems (B-1), sandy soils (B-2), chestnut soils (B-3). The research was carried out on the basis of the laboratory of quality control of grape and wine products and of ARRIV&W, a branch of FSBSI FRASC. The research revealed the influence of different types of soils on the physico-chemical parameters of musts and wines, in particular on the content of titratable acids, as well as phenolic and nitrogenous substances, which play an important role in the formation of organoleptic properties of wines. According to the organoleptic analysis, the highest tasting score (8.7 points) was given to a wine sample made from grapes grown on chestnut soils, which had the most complete and harmonious taste with light nutmeg and floral tones in the aroma.
At the moment, there is no systemic scientific knowledge about the mechanisms of the influence of the grafted culture on the quantitative and qualitative indicators of grapes and wine production. Establishing the regularities of the influence of various norms of the grape bush load in own-rooted and grafted culture on the grape quality, as well as the aesthetic and biological value of wine products in conditions of terroir changing biotic properties, is very relevant at the current stage of development of the wine-making industry in Russia. The objects of research were grapes and wine material of the Krasnostop AZOS variety in grafted and own-rooted culture with variants of different shoot load on the bush. The experiment of studying the influence of various agrotechnical methods on the productivity of a grape plant and the quality of wine material was laid in the Anapo-Taman climatic zone of the Krasnodar region of Russia. The highest yield of the Krasnostop AZOS variety during the years of the study was obtained in the variant of own-rooted grape growing with its load of 36-40 shoots per bush. In our studies, there is a tendency to an in-crease in grape sugar content and a maintenance of the titratable acidity when the Krasnostop AZOS variety is growing on vineyards in own-rooted culture. The most optimal ratio of sugar content and titratable acidity in the experiment was possessed by grapes from a variant of own-rooted culture with a load of 36-40 shoots per bush the glucoacedometric indicator was 4.36. In the studied variants, the largest number of phenolic substances was found in wine material from own-rooted grapes with a load of 36-40 shoots per bush 4130 mg/dm3 . This had a positive effect on the organoleptic evaluation of this sample. The largest total amoun of biologically active substances in the studied samples was found in wine materials from grapes in a grafted culture (134.9-147.9 mg/dm3 ). During the years of study, wine materials from grapes of own-rooted culture proved to be of the highest quality. This advantage over the grafted crop was traced in all variants of rationing the shoot load of grape bushes.
The crops products taste is the main characteristic that determines its appeal to consumers. Therefore, at different stages of the breeding process, it is important to have a competent tasting procedure, results of which require statistical analysis and graphics. The article proposes to use cluster heat maps (HM) to visualize the experts agreement when tasting products. The material for the study was questionnaires obtained in 2020 during the assessments of 10 varieties of blue honeysuckle Lonicera caerulea L. 12 experts were involved in the tasting, who evaluated the sensory characteristics of berries, including taste, on a five-point scale. Statistical analysis of the obtained data included the calculation of the Kendalls coefficient of concordance W, the average scores, as well as the construction of a cluster HM. To group the columns and rows of the data matrix in the CH, we applied hierarchical cluster analysis using Spearman's correlation coefficient as a measure of similarity, and Ward's method as an agglomerative algorithm. Calculations were carried out in the DescTool and pheatmap packages of the statistical environment R. As a result, it was found that the agreement of experts in the ranking of varieties was statistically significant (P < 0.001), but weak: W=0.374. Therefore, the average scores for varieties do not contain all the information and a heatmap was built to expand it. This article describes a statistical standardization procedure for color-coding cells of HM. Based on the heatmaps analysis, the individual characteristics of the honeysuckle variety and the individual taste of experts, the grouping of varieties and the grouping of experts and/or consumers are discussed. It is concluded that the cluster heatmap is a useful tool combining statistical and graphical techniques that is useful even in the absence of expert agreement.