Genetic diversity of apple landraces from VIR collection based on SSR markers

Genetic diversity of 108 apple landraces from the Northwest and Central Russia and Northern Europe preserved in the collection of Pushkin and Pavlovsk Laboratories of VIR was studied using a set of ten SSR markers. The detected polymorphism level was rather high: 11.6 alleles per locus were identified, PIC value averaged 0.74, expected and observed heterozygosity averaged 0.76 and 0.59 respectively. High frequency of rare (57.76%) and unique (20.69%) alleles was found. Three markers (CH02c02a, CH03d01 and any of CH01f03b, CHVf1 or CH05e03) are sufficient to distinguish each of the studied accessions. Cluster analysis did not reveal clear differentiation of the landraces based on their geographic origin, as well as in previous studies. The results provide valuable information for identification and rational management of the material preserved in VIR collection and confirm high genetic diversity level of the studied apple landraces, indicating their potential for breeding. Together with the data on SSR loci polymorphism of apple landraces from Volga region, Caucasus and commercial apple cultivars the results will allow further genetic diversity assessment of VIR collection.