Molecular characterization of some olive cultivars found in Fadak farms in Karbala By Using Internal Transcribed Space (ITS1)

Abstract

The identification and organization of olive (Olea europaea L.) cultivars are crucial for improving olive production, protecting genetic diversity, and ensuring the authenticity of local varieties. This study aims to describe the genetic diversity of cultivars grown in Karbala Governorate, Iraq, using the internal transcribed spacer region of the nuclear ribosomal DNA. Fifteen leaf samples were collected from Fadak farm, and total genomic DNA was extracted. PCR amplification of the ITS1 region was accomplished using specific primers, and the products were sent for sequencing. The resulting sequences will be aligned and compared with those deposited in GenBank to determine the degree of similarity and to construct a phylogenetic tree, thereby enabling cultivar identification and assessment of genetic variation. Results showed that of ITS1-5.8S-ITS2 sequences from five Olea europaea samples collected in Iraq revealed varying degrees of genetic similarity with known cultivars. Four samples showed high sequence similarity (above 96%) to established cultivars such as Olive yellow, Picual-Bakraju-Sulaymani, and Qaysi-Alqush-Musil, indicating close genetic relationships and potential affiliation to these cultivars or their local variants. One sample exhibited a lower similarity (92.3%) with Khoderi-Bakraju-Sulaymaniya, suggesting it may represent a distinct local isolate or a unique genetic lineage within Iraqi olive diversity. These findings highlight significant genetic variation among Iraqi olive populations and emphasize the importance of further morphological and agronomic characterization to clarify their taxonomic status.