Genetic diversity and phylogenetic structure of Marawh and Bidah pomegranatelandraces from Al-Baha, Saudi Arabia, using ITS DNA barcoding

Pomegranate (Punica granatum L.) plays a vital cultural and economic role in the Al-Baha region of Saudi Arabia. Despite its significance, limited molecular data exist on the genetic structure of local landraces, particularly the distinct red and green fruit colour variants of the Marawh and Bidah cultivars. This study investigates the genetic diversity and phylogenetic relationships among these landraces using the nuclear internal transcribed spacer (ITS) DNA region. Maximum likelihood phylogenetic tree construction and network analysis (SplitsTree) were employed. Results reveal that red- and green-fruited landraces cluster into distinct clades, with red variants exhibiting reticulate patterns suggestive of introgression or incomplete lineage sorting. Genetic distance analysis confirmed a high similarity (~99.15%) between the green variants, despite their placement in separate clades. The findings provide crucial insights into the evolutionary history, cultivar authentication, and conservation strategies for pomegranate germplasm in Al-Baha. Future directions include genome-wide SNP analyses and expanded sampling to refine our understanding of these valuable genetic resources.