Molecular evaluation of germplasm is an important step in breeding programs, and the application of molecular biological techniques has led to important results in terms of both within- and between-species variability of traits. The RAPD technique has been successfully used to reveal allelic polymorphism as well as to measure genetic similarity. In this study, the genetic diversity of 25 genotypes and cultivars for apple species and 26 genotypes and cultivars for plum species was assessed with six RAPD markers. All these cultivars belong to the ex situ collection of apple and the ex situ collection of plum at the Research Institute for Fruit Growing Pitesti. The average number of amplified bands was 19.2 for apple and 17.66 for plum. Statistical analysis of intraspecific allelic polymorphism was expressed using the PIC (Polymorphic Information Content) index, which takes into account the allelic frequency. Two statistical indices were used to quantify genetic diversity: the Shannon index and the Simpson index. The degree of similarity between varieties was analyzed using the NTSYSpc version 2.1. Following RAPD analyses, the allele sizes of the analyzed varieties were within the range quoted in the literature, the genetic profiles of the studied varieties suggesting a medium to high genetic diversity, except for markers OPBC-04 and OPBB-05 for plum species, which expressed a high genetic diversity. Genetic distances calculated based on polymorphism of migrated bands in agarose gel confirmed the known genealogies of the apple and plum varieties studied. Thus, the smallest genetic distance for apple species was found between 'Jonagold' and 'Golden Delicious', 'Pionier' and 'Rustic', 'Jonathan' and 'Idared', 'Wagener Premiat' and 'Granny Smith', 'Remar' and 'Aura', 'Romus 3' and 'Rome Beauty', and the largest between Malus floribunda and the other genotypes studied. In plum, the smallest genetic distance was found between 'Dani' and 'Tita', 'Roman' and 'Tuleu gras', 'Dara' and 'Haganta', 'Romanța' and 'Stanley', 'Anna Spath' and 'Renclod Violet', and the largest between 'Lama', 'Black Diamond' and the other genotypes studied.
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