A b s t r a c tBlack currant is the main berry crop in Russia. The need to improve its assortment requires new effective methods to be involved in breeding. Application of DNA markers as a modern approach in dealing with germplazm is intensively used abroad in works on black currant plants. We are the first in Russia who used SSR DNA markers in studying black currant gene pool. In this paper we report genotyping 27 black currant accessions from the collection of the All-Russian Research Institute of Breeding Fruit Crops, including 16 varieties originated from this institute, on 14 microsatellite loci. Electrophoresis in 6 % denaturing PAAG followed by staining with silver nitrate was used for separation of PCR products. All tested SSR loci, except MS06g03, have been found to be polymorphic. On average 4.9 alleles were amplified per locus. Three fragments have been amplified on DNA of some accessions at one SSR locus that is probably due to the duplication of these microsatellite loci in genome of these accessions. A total of 66 % of all amplified fragments were rare alleles with a frequency of occurrence equal to or less than 0.2. Eight unique alleles have been found. The observed heterozygosity ranged from 0.259 (g2-H21) to 1 (e4-D03) and averaged 0.608. Combinations of alleles at one locus allowed to distinguish from 3 (g2-H21, e1-O21) to 15 (g2-G12) genotypes. The minimum set of four loci (e4-D03, g1-M07, g1-E03, g2-B20) allowed to distinguish all the tested accessions, i.e. unique multilocus profile has been found for each sample. Pairwise genetic similarity coefficients ranged from 0.11 (between Odzhebin and Sharovidnaya varieties) to 0.95 (between Govtva and Rtishchevskaya varieties) and averaged 0.346. Cluster analysis of genetic similarity has been done. The dendrogram shows a few clusters with high bootstrap support. Distribution of alleles between related varieties was consistent with the pedigrees in the most cases, but discrepancies between pedigrees and SSR data also were found. Thus, the varieties Ocharovanie (¹ 1168 ½ Ekzotika variety) and Ekzotika had no common alleles in three loci (e4-D03, g1-E03, g2-B20). It probably is due to pollination by other pollen or error in reproduction and transplantation or mutations in these loci. The varieties Odzhebin and Binar (Odzhebin ½ Naryadnaya) had no common alleles in two loci (g1-M07, g1-E03). Our results allow to recommend SSR markers for evaluation of domestic gene pool of black currant on genetic diversity, and to develop methods for the identification and certification of varieties of black currant.

The physical and mechanical parameters of berries and the morphometric features of the structure of the bush growth habit are important criteria in predicting the use of berry harvesting equipment. In this research, six red currant cultivars have been studied. The berry separation force, the crushing force, and the strength of attachment of the berries to the stalk were assigned to the physical and mechanical parameters and were determined using the "PLODTEST-1" and "Dina-2" devices (Russia). For the optimal operation of the berry harvester, the crushing force of the berries must be more than 2 N, the berry separation force must be in the range of 0.5–1.5 N. A high correlation between the separation and crushing forces was determined (R = 0.71). During the period of technical maturity, the strength of the attachment of the berries in the raceme was more than 0.5 N and, by the end of maturation, this indicator decreased. Most of the studied cultivars have a compact, optimal bush volume. The red currant cultivars Niva, Asya and Vika are promising for mechanised harvesting.

The aim of this work was to study the mechanism of climatic adaptation of red currant genotypes (Ribes rubrum L.) on the basis of physiological, biochemical and agrometeorological measurements and to determine the different phenophases of plant development identify adaptive genotypes for introduction. The studies were carried out in 2014–2017. The indicators of the water status of annual shoots (water content, water retention capacity), the biochemical composition of berries (vitamin C) and phenological observations were evaluated, taking into account meteorological data. The genotypes of R. petraeum Wulf. and R. multiflorum Kit. had the longest production period. Ambiguous data on the influence of temperature on the content of ascorbic acid in berries were revealed. High temperatures (>+26 °C) contributed to a greater accumulation of ascorbic acid in the cultivars of R. vulgare Lam. High accumulations of vitamin C in the range of +25–27 °C were found in R. petraeum Wulf. and R. multiflorum Kit.. High water content and water loss contributed to early recovery from the dormant state and reduced resistance to spring temperature changes in R. vulgare Lam. Genotypes of R. vulgare Lam., and R. multiflorum Kit. are promising for growing in a zone with a temperate continental climate. The genotypes of the species R. petraeum Wulf are suitable for introduction to the areas with a continental climate. The obtained results are important for adaptive gardening.

No abstract

The aim of the work was to study the growth, drought tolerance and biochemical characteristics of introduced cultivars (‘Jonkheer van Tets’, ‘Hollandische Rote’ and ‘Viksne’) and some selected Russian cultivars and red currant genotypes (‘Shchedraya’, ‘Natali’, 129-21-61, 111-19-81, 261-65-19 and 271-58-24). The studies were conducted between 2014 and 2018 under temperate continental climate conditions. The intensity of transpiration was determined by using a torsion balance. The soluble solid concentration (SSS – % Brix) of the fruits was determined by using a digital refractomer. The content of the sum of sugars was determined by the weight method according to Bertrand's method. Ascorbic acid content was then determined by the iodometric method. The total phenolic content was determined by a colourimetric method. Climatic conditions were found to have significant influence on the disease severity of the red currant genotypes, while the infections caused by Sphaerotheca mors-uvae increased in optimum seasons and damages caused by Pseudopeziza ribis increased in drought seasons. None of the selected genotypes was found to be resistant to any of the diseases/pests, but ‘Jonkheer van Tets’, ‘Hollandische Rote’ and 111-19-81 were less affected by these diseases/pests. Weight, yield and raceme length of berries and the number of berries in a raceme were found to be higher in optimum seasons, and different cultivars/genotypes had superior characteristics for different parameters. The highest berry weight was observed in the 261-65-19 genotype (0.65 g), while the highest yield was noted in ‘Hollandische Rote’ (15.6 t · ha−1). It was also found that the water content of leaves and transpiration have a strong positive relationship with soil moisture at a depth of 0–200 mm but a week correlation with soil moisture at a depth of 200–400 mm. Results also showed that the transpiration of leaves decreases in later developmental stages (July). Hierarchical clustering suggested four clusters: the introduced cultivars produced one cluster, Russian cultivars are another cluster, 261-65-19, 111-19-81 and 129-21-61 genotypes make up a third cluster and the 271-58-24 genotype (superior in terms of phenolic contents) forms the fourth cluster.