Exploring Phylogenetic Relationships and Genetic Variability of Date Palms (Phoenix dactylifera L.) in Ethiopia Using ISSR Markers

Abstract

Date palms (Phoenix dactylifera L.) have socio-economic importance and ecological functions in arid regions, but are poorly studied in Ethiopia. This paper examines the hereditary framework and diversity of date palms native to Ethiopia. To achieve this, we analyzed 113 distinct samples through the application of 10 specific ISSR (Inter-Simple Sequence Repeat) primers. 241 distinct DNA fragments were successfully generated via PCR; notably, all employed ISSR primers revealed complete polymorphism (100%), indicating high genetic diversity. Among the tested markers, the AGG6 ISSR primer exhibited the highest degree of productivity, yielding a total of 37 distinct amplification products, whereas the AG₁₀C primer produced the fewest (10) amplification bands. Diversity indices, including Shannon’s Information Index (I) and Nei’s genetic diversity (H), revealed significant variation among date palm populations. Analysis of Molecular Variance (AMOVA) revealed that 51% of the total genetic variation was attributable to differences among the sampled Ethiopian date palm populations. These differences were due to population-level variation, suggesting limited gene flow between populations and relative isolation, which contrasts with what is typically observed in long-lived plants. AMOVA analysis found that over half (51%) of the genetic differences between the results from the principal coordinate analysis and dendrogram (UPGMA clustering) showed that the different types of date palms grouped based on where they come from. The current research highlights special genetic resources for creating breeding programs that can withstand climate challenges, especially for date palms in the Horn of Africa, which can survive climate change and drought problems in the region.