Diversity of morpho-physiological traits in worldwide sweet cherry cultivars of GeneBank collection using multivariate analysis

- Morphological characterization was assessed using quantitative and qualitative traits.
- Correlation between several morphologic traits are identified and analyzed.
- Hierarchical classification allowed the identification of morphological typologies.
- Variability of the morphological traits of worldwide sweet cherry germplasm collection is compared.
- This research could substantially contribute to existent sweet cherry breeding programs.

This study presents an assessment of morpho-physiological diversity for one hundred and forty-six sweet cherry (Prunus avium) cultivars, originating from different countries and maintained in an ex situ GeneBank collection. Data of thirty-five traits, describing phenology, plant morphology, yield and fruit quality were recorded over three years and analyzed using principal component analysis (PCA). An unsupervised hierarchical cluster analysis was performed the different cultivars using the Euclidean distance metric and the Ward's agglomeration method. Significant positive and negative correlations were detected among the different morpho-physiological traits. The sweet cherry cultivars were classified into three main clusters, suggesting that the characterized sweet cherry collection has high potential for specific breeding goals. Correlations among the traits, which will be useful for breeding in fruit size and quality, are discussed. Sweet cherry cultivars, which were classified in diverse clusters, could be potential parents for hybridization and new genotypes could be created with a combination of desirable traits that complement one another. These new genotypes could have a high heterotic behavior and thus could substantially contribute to existent sweet cherry breeding programs.