Phenotypic and genotypic characterization in the collection of sour and duke cherries (Prunus cerasus and ×P. ×gondouini ) of the Fruit Genebank in Dresden-Pillnitz, Germany

Phenotypic and genotypic characterization of existing sour and duke cherry cultivars provide information for use by breeders in developing cultivars with improved qualities and for germplasm management to optimise the conserved diversity. This study examined 79 sour and duke cherry cultivars of the Fruit Genebank of the Institute for Breeding Research on Fruit Crops, Dresden-Pillnitz. For morphological analysis, 23 descriptors of the tree, the flower or the fruit, and three phenological characters were recorded to detect similarities and differences among the cultivars. Most of the characteristics exhibited a high degree of variability. Principal component analysis revealed that the first three components were responsible for 48 % of the phenotypic variability. Color descriptors as well as the fruit size and weight, the organoleptic quality and the two descriptors related to the abscission between fruit and stalk were the most effective parameters to discriminate genotypes. The genetic analysis was performed using six microsatellite markers recommended by the European Cooperative Program for Plant Genetic Resources. The average number of the effective alleles was 7.11 and the expected heterozygosity ranged from 0.78 to 0.89. The highest expected heterozygosity was achieved with the primer pairs EMPaS10 and EMPaS12. The tree comparison (‘bipartition distance’) estimated by the two data sets, morphological and genetic, revealed a tree distance of 0.669. Apparently, more research is needed for combining and jointly interpreting phenotypic and genetic marker data in diversity analysis for plant breeding and germplasm management.