CHARACTERIZATION OF SELECTED SWEET CHERRY (Prunus avium L.) CULTIVARS BASED ON DUS (DISTINCTNESS, UNIFORMITY, STABILITY) CRITERIA

Sweet cherry (Prunus avium L.) is a fruit crop of high economic and nutritional value. Accurate analysis and identification of its cultivar diversity are essential for the conservation of genetic resources, planning of breeding programs, and development of new cultivars. In this study, twelve cherry cultivars grown in Azerbaijan were evaluated according to the UPOV DUS (Distinctness, Uniformity, Stability) criteria and the PPV&FRA (Prunus Genetic Resources Center, INRAE) methodology. During the research, a systematic assessment of the morphological characteristics of the fruits of various cherry cultivars was conducted. The analysed morphological parameters included fruit weight, fruit length, fruit width, fruit shape, skin and flesh colour, juice colour, peduncle length, seed weight and shape, as well as juiciness and taste quality. The results obtained revealed significant variation in these traits among the cultivars. Fruit shapes were identified as kidney-shaped, elongated, heart-shaped, and oval, while skin and flesh colours were observed in yellow, red, pink, and black shades. Peduncle length was categorized into short, medium, and long groups according to the cultivars. These parameters were considered important indicators for DUS tests and breeding programs. Seed weight was at medium to high levels, and seed and fruit shapes exhibited elliptical, round, and oval structures. The results indicate that fruit skin colour, taste quality, peduncle length, and seed characteristics play a decisive role in cultivar identification and the assessment of consumer quality. The study also emphasizes the significance of morphological variation among cultivars and provides a valuable scientific database for breeding programs and genetic resource conservation. At the same time, the results allow the evaluation of the relationship between morphological and biochemical traits of the fruit, which has practical significance for ensuring high-quality cherry production and determining compliance with DUS standards. Their genetic diversity provides broad opportunities for breeding work aimed at developing new, more productive cultivars that are resistant to diseases and climate change.