Investigation on molecular phylogeny of some date palm (Phoenix dactylifra L.) cultivars by protein, RAPD and ISSR markers in Saudi Arabia

Date palm (Phoenix dactylifra L.) is one of the most important fruit crops in the Middle East. Kingdom of Saudi Arabia lies among the largest date palm fruit producer worldwide. However, little knowledge is currently available about the molecular characterization of date palm cultivars in this country. Determination of genetic variability and cultivar identification in date palm are two major importance in breeding programs, characterization of germplasm, and conservation purposes. Three types of markers such as protein, RAPD-PCR, and ISSR were applied on four important cultivars in Saudi Arabia (Med300l b1, Sugay1 b1, Khalas b1 and Sukkarib1). Intervarietal variations were investigated using five RAPD and five ISSR markers. Most of the studied markers showed intervarietal polymorphism. Protein markers were also applied to assess the genetic polymorphism. Cluster analysis by UPGMA showed two main clusters. Cultivar Sukkarib1 was located on the cluster A, with Nei and Li's coefficient equal to 0.55. Cluster B consisted of 3 other cultivars, Med300lb1, Sugayb1and Khalasb1 with 0.66-0.85 Nei and Li's similarity range. Sugay b1 and Khalas b1 were the two most closely related cultivars among the four cultivars with the highest value in the similarity for Nei and Li's coefficient 0.85. Med 300l b1 was also closely related to Sugay b1 and Khalas b1 with second highest value in the similarity matrix 0.66. The average similarity among the four cultivars was a bit more than 55%. Most of cultivars had the narrow genetic diversity as already expected. The result of the analysis can be used for the selection of possible parents to generate mapping populations.