Assessment of Genetic Variability within and among Portuguese Apple Cultivars Revealed by SSRs

The objective of this study was to analyse genetic relationships among Portuguese apple cultivars and to compare them with standard cultivars present in Europe and in the United States. Samples were collected from apple orchards located in different areas of Portugal, both mainland and archipelagos. Of the 12 SSR loci analysed, 10 produced DNA polymorphisms. All tested cultivars could be discriminated by their allelic profiles. A dendrogram was calculated based on SSR data. Portuguese cultivars most probably derive from a common gene pool and considerable gene flow has apparently taken place among the regions. Results from this study illustrate the genetic diversity present in Portugal and can provide a basis for making decisions about the conservation of germplasm for future apple improvement.