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Eighty-two genotypes of Rubus available in germplasm collections, nurseries and home gardens were collected and evaluated using a set of 16 simple sequence repeat (SSR) markers to estimate the level of genetic diversity and relatedness of the germplasm and for testing them on trueness-to-type. Each of the 16 SSRs was successful in amplifying alleles from most genotypes. Fifteen of the markers produced polymorphic bands, whereas marker RhM023 was monomorphic. The polymorphic information content among genotypes varied from 0.056 to 0.83 with an average of 0.348. A neighbor-joining analysis allocated the genotypes to four major clusters containing 11, 24, 39 and eight genotypes, respectively. Cluster I consists of floricane-fruiting cultivars originating from the Scottish and/or British breeding programs or cultivars which have those cultivars in their pedigree. Cluster II included cultivars that have ‘Autumn Bliss’ or ‘Tulameen’ in their pedigree. Cluster III consists of summer-bearing raspberry cultivars, some primocane-fruiting cultivars, and a few intermediate summer-fall-bearing types. Cluster IV consists of the blackberry ‘Navaho’ (R. fruticosus L.), the interspecific hybrid ‘Dorman Red’ and a few other raspberry varieties. A number of yellow fruited varieties was dispersed on three different clusters suggesting a convergent evolution of this trait. The pedigree of several genotypes could be confirmed using a Pedimap based approach, whereas other cultivars were found to be genetically identical. The results disclose the alarming narrow genetic base of Rubus resources in Germany. Broadening of this base is urgently needed.

A total of 188 German and 28 Romanian pear accessions were evaluated using flow cytometry and molecular markers to detect homonymous and synonymous genotypes, triploids, which are not useful for breeding, and genotypes having favorable traits for breeding. Genotyping was done using a set of 11 simple sequence repeat markers proposed by the European Cooperative Program for Plant Genetic Resources, along with a standard set of six reference pear genotypes used in previous studies. The observed number of alleles ranged between 21 and 38 per locus. Twenty-three accessions could be confirmed as triploids. Because of the expected cross-incompatibility they are only of limited interest for breeding. The study confirmed that 180 of the 188 tested German accessions represent unique genotypes, while some accessions were found to be genetically identical. In parallel additional markers, which are known to be linked to resistance/susceptibility to major pathogens (e.g. black spot, aphid, fire blight, and apple scab), were applied to the German accessions. The comparative screening of the Romanian pear genetic resources demonstrated that only a few accessions with identical/very similar names to German accessions really have an identical fingerprint. Mislabeling and homonymous designation of different genotypes seems to occur frequently in different collections.

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.

A collection of 337 Malus accessions representing 46 species of the Fruit Genebank in Dresden-Pillnitz, Germany, were evaluated for 64 morphological and phenological traits to proof the classification of the accession and to analyze genetic relationships. Morphological characteristics were determined for the whole tree, shoots, leaves, flowers and fruits. Data were subjected to principal component analysis (PCA), and a dendrogram was constructed to demonstrate morphological relationship. According to PCA the most important variables integrated in the first principal component were mainly fruit descriptors and three traits characterizing pubescence (1 year old shoot, leaf blade, and pedicel). Cluster analysis clearly separated the accessions in Malus series. The results showed the polyphyletic origin of the section Sorbomalus. The North American apple species, M. fusca, was closely related to the species contributing to the East Asian center of the genus origin. The relict species of the European continent (M. trilobata) was grouped in near distance to the North American species belonging to section Chloromeles. The species of Sieversinae and Baccatae dominated in one main cluster indicating their close relatedness. Most of M. ×domestica accessions were grouped with M. sieversii and M. orientalis; this supports the Sievers apple as an ancestor of domesticated apple. The morphological evaluations in this study indicated a high level of phenotypic diversity in the genebank collection. These phenotypical data will increase the feasibility of prioritizing accessions based on the uniqueness of desirable morphological traits.