Evaluation of sweet cherry (Prunus avium L.) cultivars for fruit size by FW_G2a QTL analysis and phenotypic characterization

Large fruit size of sweet cherry cultivars has high priority in breeding programs due to its high market value. According to recent studies more loci were identified corresponding to fruit size trait in cherries. In our study 15 Hungarian sweet cherry cultivars were evaluated for the locus FW_G2a on LG2 and genetic results were compared with phenotypic data of 3-8 years. Average fruit weight of sweet cherries ranged from 3.9 g (Muncheberger Fruhe) to 10.3 g (Carmen). Haplotypes associated with large fruit size were found in 11 cultivars, of which five (Germersdorfi acute accent Ori acute accent as, Katalin, Vera, Krupnoplodnaya, Carmen) proved to be homozygous. Two cultivars (Petrus and Stella) carried the haplotypes associated with small fruit size. Statistical analysis revealed correlation between genotype data and fruit weight phenotype. Our results confirmed that genotyping the locus FW_G2a is an effective tool in early selection of individuals and can be utilized in cherry breeding programs.