Turkish Journal of Botany, cilt.50, sa.3, ss.260-271, 2026 (SCI-Expanded, Scopus, TRDizin)
Grape (Vitis vinifera L.) is an economically important fruit that is both consumed fresh from the vine and used in the production of raisins, wine, and vinegar. One of the main factors limiting grape production is gray mold, caused by the fungal pathogen Botrytis cinerea. The cultivation of mold-resistant grape cultivars represents the most effective strategy for disease management; however, molecular tools to aid in the breeding of B. cinerea-resistant grapes remain limited. The present study maps the quantitative trait loci (QTLs) associated with B. cinerea resistance in grape using an F1 population derived from a reciprocal cross between the “Yalova İncisi” and “Kyoho” cultivars. A high-density genetic linkage map was constructed using 5831 single-nucleotide polymorphism (SNP) markers and 350 simple sequence repeat (SSR) markers, spanning all 19 grape chromosomes. Subsequently, four major QTLs were identified on chromosomes 2, 14, and 18, three of which (Bc2.1, Bc18.5, and Bc18.3) contained candidate genes involved in resistance to biotic stress. Furthermore, a cleaved amplified polymorphic sequence (CAPS) marker—SNP2—was developed, showing 74% concordance with classical phenotyping for resistance linked to the Bc18.5 locus on chromosome 18. This is the first study to map QTLs controlling B. cinerea resistance, and to develop CAPS markers for marker-assisted selection (MAS) in grape breeding. The QTLs identified here can be considered valuable targets supporting the future development of molecular breeding tools.