Molecular Characterization of Romanian Pear (Pyrus communis L.) Germplasm Using SSR Markers

Abstract

The conservation and molecular characterization of pear genetic resources are essential for sustainable breeding and the preservation of genetic diversity. In this study, 75 pear genotypes maintained in an ex situ germplasm collection at the Research Institute for Fruit Growing (RIFG), Pitești-Mărăcineni, Romania, were characterized using SSR markers. The selected markers generated highly reproducible profiles, and UPGMA cluster analysis confirmed the technical robustness of the dataset for primary screening. Biological replicates consistently grouped together in terminal clades, confirming broad cultivar identity and macro-level clonal stability within the collection, while also establishing a baseline for future high-resolution genomic evaluation. The genetic relationships revealed a clear geographical and historical structure, separating genetically diverse traditional Balkan cultivars from the more closely related Western European commercial cultivars, particularly those belonging to the ‘Williams-Beurré’ group. Molecular data also provided evidence of genetic relationships among recently developed Romanian cultivars, highlighting the successful incorporation of elite international germplasm into local breeding programs while preserving adaptive and fruit quality traits. This study provides an extensive SSR-based molecular assessment of the pear germplasm repository maintained at RIFG Pitești-Mărăcineni and demonstrates its value as a genetic resource for biodiversity conservation and the development of resilient cultivars adapted to future climatic and biotic challenges.