Genetic Diversity Assessment of Palestinian Okra Landraces (Abelmoschus esculentus L.) Through RAPD Marker

Genetic diversity within germplasm holds significant importance in the context of okra breeding programs. However, the limited knowledge regarding the genetic diversity of okra in Palestine poses a challenging obstacle to enhancing the local cultivar. Characterization of Palestinian okra landraces using phenotypic or molecular approaches is limited. Crop characterization usually provides knowledge on diversity within and among crop accessions, which is crucial for breeding efforts and the conservation of germplasm. This study was carried out to evaluate genetic variation in seven okra local landraces. Seven Palestinian okra landraces were grown. DNA was extracted and subjected to polymerase chain reaction (PCR) using 27 random amplified polymorphic DNA (RAPD) markers. The banding pattern for each primer was scored. The data matrix was created to facilitate cluster analysis employing the unweighted pair group method with arithmetic mean (UPGMA) method. From the 15 RAPD markers tested, 92 DNA fragments were identified in total, of these fragments, 76% were polymorphic and 24% were monomorphic, in addition, at least two and no more than eleven DNA fragments were identified. The average resolving power recorded was 2.8. The dendrogram derived from RAPD data categorized the genotypes into two primary clusters. Cluster-I consisted of a single genotype (PARC-OKRA-1). In contrast, Cluster-II further subdivided the genotypes into two subclusters, sub-cluster-II.a represented one genotype accession (UB 405-19), and sub-cluster-II.b included five genotypes (UB 457-19, UB 280-15, UB 457-14, UB 280-12, and UB 457-20). The generated similarity matrix indicated that the similarity coefficients among okra genotypes, as determined by 15 RAPD markers, ranged from 0.226 to 0.678. The present study represents the first application of molecular markers to assess genetic diversity within Palestinian okra landraces. The detection of a high level of polymorphism among RAPD markers demonstrated the efficacy of RAPD markers for identifying polymorphism in Palestinian okra genotypes.