Utility of partial 26S rDNA sequences in DNA-based identification of endemic plants

Endemic and rare plant taxa are critical components of biodiversity, playing key roles in ecosystem stability and resilience. However, these species are increasingly threatened by habitat loss, climate change, and anthropogenic pressures. Molecular approaches, particularly DNA barcoding, have become essential for accurate species identification and the assessment of genetic diversity. In this study, we evaluated the effectiveness of the partial 26S rDNA region as a DNA barcode marker for the molecular identification of 30 endemic and rare plant species from Kars Province, Türkiye. To our knowledge, this is the first application of the 26S rDNA region in these taxa. Sequence analyses revealed no exact matches in the GenBank database, indicating potential novelty and underscoring the scarcity of reference data. A total of 42 variable sites were identified across the sequences, and phylogenetic analyses largely clustered the species in accordance with their taxonomic families. Importantly, 30 novel barcode sequences were generated and submitted to public databases, offering valuable resources for future taxonomic, phylogenetic, and conservation-oriented studies. This work demonstrates the utility of partial 26S rDNA sequences for the molecular characterization of understudied endemic plants and provides a foundational step toward enhancing biodiversity documentation and conservation efforts in Türkiye.