ISSR Analysis for Determination of genetic diversity in 29 olive (Olea europaea L.) cultivars

Olive tree is one of the most important oleaginous crops in the world, and known for having large genetic variability. Application of molecular markers is a suitable tool to investigate the genetic pool in crops. Therefore, in the current study 29 olive cultivars were tested by ten primers constituted by inter simple sequence repeats (ISSR). Plant materials were obtained from the collection of Tarom Agricultural Research Center in 2015. Genomic DNA was extracted from fresh leaves of 29 cultivars by a modified CTAB method. Ten ISSR primers were used and obtained data were scored. An analysis of primer informativeness showed that all primers were productive and effective in separating olive cultivars. Nevertheless, some of them were more effective such as UBC 855 and UBC 825 primers. According to cluster analysis and genetic distance, the olive cultivars were separated into three major clusters. Majority of the cultivars from southern and central Mediterranean such as; Italian, Spanish and Grecian olive cultivars clustered in one group. Results of the current study suggest that Mediterranean olive germplasm were structured into two main gene pools, which strongly matched two distinct geographic areas, i.e. western and central as well as eastern Mediterranean regions.