Characterization of palm date varieties (Phoenix dactylifera L.) growing in Saudi Arabia: Phenotypic diversity estimated by fruit and seed traits

Abstract

In order to determine the variation and the degree of diversity among the most well-known Saudi date palm (Phoenix dactylifera L.), this study applied various widely detectible fruit and seed features. The properties of the fruit and seeds were described using ten phenotypic traits. Eighteen date palm varieties from six production sites were used in this study (Ḥaʼil, Al-Madina, Al-Hassa, Al-Qassim, Kharaj, Najran). The data was analysed by Pearson r correlation. The principal components analysis (PCA) and UPGMA clustering were used to analyse the data set. According to PCA, the results showed significant variation among the analysed varieties. Our data shows that seed ratio varies among all varieties. The mean seed weight ratio varies between 4 and 13%. Varieties ‘Raziz’, ‘Lubab’ and ‘Wasily’ demonstrate higher seed ratio (over 10%). Whereas, Fankha depicts a 5 and 4% fresh and dry seed ratio. The statistical analysis indicates that the seed ratio in all 18 varieties is comparable in fresh and dry fruits. The result suggests variation among the numerous features due to dissimilarities and heterogeneity. However, the obtained results also propose the clustering and grouping of closely related features, e.g., weights of fresh and dry fruits. Eventually, it is suggested to conduct additional research on Saudi date palms utilizing more phenotypic traits in order to have a better understanding of the pack of morphological descriptors.