Insight into Date Palm Diversity: Genetic and Morphological Investigations

摘要

Date palm (Phoenix dactylifera) is an important crop plant both from nutritional and economic points of view. The assessment of genetic diversity and population differentiation of date palms are evaluative for its dynamic conservation and sustainable utilization of its genetic diversity. Estimates of genetic diversity based on molecular markers and fruit characteristics were performed in samples of 23 date palms growing in Ahvaz city (Khuzestan province of Iran). Clustering based on fruit morphological features separated the cultivars in different groups. These cultivars differed significantly in morphological features (P = 0.001). Start codon targeted (SCoT) polymorphism markers revealed a good level of genetic variability (10.17 to 45.76%) in these cultivars. Moreover, STRUCTURE analysis revealed the presence of within-population genetic variability. Analysis of molecular variance revealed a significant genetic difference among date palms, while it showed a higher degree of within-cultivar genetic variability compared with that of among-population diversity. Some degree of common shared alleles occurred between date palm cultivars. Gst versus Nm analysis showed that some of the SCoT markers have a high discrimination power and may have a potential local adaptive value. The Mantel test showed a significant association (r = 0.40,P = 0.001) between morphological and genetic distances. Therefore, both morphological and SCoT molecular data can be used in genetic screening of date palms in the available germplasm.