Evaluation of genetic polymorphism in the cultivars of garden strawberry and an interspecies hybrid (Fragaria × anaschata) via SSR marker analysis

Abstract

Analyzing the genetic composition of accessions from an agricultural plant collection constitutes a critical stage in breeding research that can be optimized through molecular genetic techniques. Among these, DNA marker technology represents a promising approach for determining the genetic structure of breeding material, establishing genetic profiles, and identifying cultivars. The evaluation of genetic polymorphism using SSR markers is widely employed due to its simplicity, accuracy, and reproducibility. This study aimed to evaluate genetic polymorphism via SSR marker analysis and to investigate the genetic relationships among the most promising cultivars of garden strawberry and an interspecies hybrid ‘zemklunika’ ( Fragaria × anaschata Kantor) from the collection of the Federal Horticultural Center for Breeding, Agrotechnology, and Nursery to optimize the breeding process and protect the rights of patent holders and breeders. The analysis was performed via polymerase chain reaction using ten pairs of SSR primers (FG7ab, FG7cd, FG2ab, FG2cd, EMFvi136, EMFn121, UFFa3-D11, ARSFL9, EMFxa380097, and ARSFL11). The quality of the amplification products was assessed via gel electrophoresis, while the size and number of the resulting amplicons were determined via fragment analysis. Unique genetic profiles across the ten loci were established for 27 garden strawberry cultivars (Barynya, Bereginya, Vityaz’, Vostorg, Lyubava, Udacha, Tsaritsa, Nashe Podmoskovye, Alfa, Kokinskaya Zarya, Rosinka, Kokinskaya Pozdnyaya, Kokinskaya Rannyaya, Slavutich, Studencheskaya, Festivalnaya, Sudarushka, Rubinovy Kulon, Honeoye, Clery, Lord, Darselect, Polka, Alba, Baron Solemacher, Borovitskaya, and Elizaveta-2) and one cultivar of the hybrid ‘zemklunika’ (Kupchiha). An analysis of allelic profiles for the studied accessions at these loci revealed a high level of genetic polymorphism. The genetic profiles revealed a total of 143 fragments, 100 % of which were polymorphic. The selected markers exhibited a high power of discrimination (PD), with the mean PD coefficient reaching 0.89 per locus. The cultivar genotyping results were statistically processed using cluster analysis. The studied accessions were clustered predominantly according to the presence of common parental lines, with rare exceptions presumably attributed to genetic recombination. For the clusters grouping closely related cultivars, high support was observed, demonstrating the reliability of the performed analysis. The findings of this study are highly relevant for cultivar evaluation and enable a comprehensive assessment of breeding material when planning crossings to develop new, viable cultivars with target properties.