Evaluation of original strawberry forms for resistance to gray mold in the conditions of the Middle Urals

Gray mold is one of the main harmful diseases of strawberries. Breeding for resistance to this disease still begins with identifying resistant phenotypes and using them in crosses. Since strawberries are a polygenic, heterozygous species, then in order to increase the effectiveness of breeding work, it is necessary to conduct a breeding assessment of the original forms for resistance to gray mold. The studies involved cultivars and forms of breeding of the Sverdlovsk breeding station of horticulture – ‘Duet’, ‘Forsazh’, ‘Gejzer’ 1-14-10, 2-43-10, 3-44-10, 2-45-10, 3-45-10, 2-54-11, introduced cultivars ‘Ol'viya’, ‘Solovushka’, ‘Belrubi’, ‘Cardinal’ and their hybrid offspring – 600 seedlings of 10 families. The maximum development of gray mold on the original forms of strawberries was observed in the years of epiphytoties – 2017, 2018, 2024. According to the results of the surveys, only two forms 2-45-10 and 2-54-11 were resistant to this disease. The hybrid offspring was assessed in 2024 against a natural phytopathogenic background. According to the results of breeding assessment for the yield of disease-resistant seedlings (29.0–34.1 %), families were identified in the origin of both parental forms of which cultivars with dense berries participated – ‘Marmolada’ and ‘Totem’: 1-40-10 × 3-44-10; 2-43-10 × 2-54-11; ‘Forsazh’ × 2-43-10 (29.0–34.1 %). The use of resistant forms 2-45-10 and 2-54-11 in crossings (except for the family 2-43-10 × 2-54-11) gave a lower yield of seedlings without signs of the disease (6.3–16.7 %). During the research, 10 selected strawberry seedlings were selected, combining in their genotype, in addition to resistance to gray mold, a set of economically valuable traits. These seedlings represent new source material for further selection work.