Polymorphism of Microsatellite Loci in Cultivars and Species of Pear (Pyrus L.)

Using five SSR markers, polymorphism of microsatellite loci was examined in 46 cultivars and five species of pear (Pyrus ussuriensis, P. bretscgneideri, P. pyraster, and P. elaegnifolia). Most of the accessions examined showed the presence of unique allele sets. The degree of relationship between Russian and Western European pear cultivar was established. It was demonstrated that P. ussuriensis and its first generation progeny were genetically distant from typical cultivars of P. communis, as well as from the P. communis x P. ussuriensis hybrids of later generations. SSR estimates of the cultivar relatedness were shown to correlate with the corresponding pedigree-based estimates. A number of SSR alleles specific to P. ussuriensis were identified. Based on the analysis of microsatellite loci, the allelic composition was determined for each cultivar examined. These data can serve as a molecular certificate of the cultivar.