Professor Hungarian University of Agricultural and Life Sciences, Godollo Budapest, Pest, Hungary
Body of Abstract: Most Prunus species are diploids, but higher ploidy levels can be also found: sour cherry is tetraploid and the European plum is a hexaploid species. Since those species are of crucial importance to understanding the genetic background of economically important traits of stone fruit species, we tested the application of different molecular markers to characterize the phylogenetic position, follow some economically important traits (e.g., fruit color, self-incompatibility status), and evaluate the genetic variability of cultivars and germplasm resources. Sour cherry cultivars show great variations in fruit color (ranging from light red to black) and accessions with identical phenotype were confirmed to be phylogenetically unrelated genotypes. It is explained by this trait determined by a Myb transcription factor influencing the expression of a set of anthocyanin biosynthesis genes. Highly esteemed traditional cultivars and autochthonous landraces of European plum could be discriminated from other P. domestica cultivars based on sequence variations in the chloroplast DNA (cpDNA). Our results are the first pointing to regions of cpDNA that are suitable for intraspecific differentiation within the European plum complex. The genetic analysis of polyploid Prunus fruit species is challenging due to the frequently occurring inefficient PCR amplification and the complex interaction of alleles in the polyploid genome. Therefore, we designed a new molecular marker based on start codon targeted polymorphism and a transposon preferentially accumulating in the euchromatin regions of the Prunus genome. Inter- and intraspecific variations were detected within or near protein-coding genes of European plum and other Prunus accessions. Our data helped to resolve some important issues, characterize the genetic background of commercial cultivars and germplasm resources as well as may provide a new molecular marker efficiently used in the genetic analysis of polyploid Prunus fruit trees.
This work was supported by the NKFI K_128874 project and the Eötvös Lóránd Research Network.