Selection assessment of varieties and selected forms of black currant based on large fruit size

Abstract

The article presents research findings on the weight of black currant berries. The research focused on the varieties and selected forms of black currant (Ribes nigrum L). Nara variety, adapted to local conditions, was used as a control. Studies were carried out in 2020–2022 at the plots for genetic collection and competitive trials of selected forms of black currants at the All-Russian Research Institute of Lupin (Bryansk region). The planting scheme involved a spacing of 3×0.8 m on grey forest soils. The observations were carried out using conventional methods. The varying weather conditions during the study period allowed for a more objective evaluation of the genotypes in terms of their adaptive capabilities and facilitated the selection of large-fruited and resistant forms. The most favourable meteorological conditions for berry weight development were observed in 2022. During this period, the average berry weight of the studied gene pool was 2.5 g. Among the examined varieties, Dobrynya (3.5 g), Debryansk (2.7 g), Chara (2.6 g) and Selechenskaya 2 (2.6 g) demonstrated the largest berry sizes with variation coefficients of 20%, 28%, 7%, and 17%, respectively. Large-fruited forms having an average berry weight exceeding 3 g and high stability (V=3%) were selected from the hybrid family 6-12- 224×6-26-207 – 7-3-227 (3.6 g), 7-3-213 (3.4 g), 7-19-100 (3.6 g) and Selechenskaya 2×Treasure – 6-20-67 (3.5 g). These genotypes represent valuable parent material for further breeding aimed at increasing berry weight. New large-fruited sources with a combination of important breeding traits (large fruit, high vitamin C content, resistance to powdery mildew and bud mite), namely,7-19-100, 7-3-227, 7-18-250, 7-13-232 and 7-17-150, were identified. The variety Dessert Olkhina exhibited the smallest berries (0.8 g) with a variability of 20%. The influence of weather conditions on the weight of berries was established, revealing a positive average correlation between berry weight and precipitation levels from May to July (r=0.52) and the hydrothermal index of the growing season (r=0.56).