Efficiency of Inter Simple Sequence Repeat (ISSR) markers for the assessment of genetic diversity of Moroccan pomegranate (Punica granatum L.) cultivars

• Genetic diversity of Moroccan pomegranate was screened using 61 ISSR markers.
• An important polymorphism was revealed in Moroccan germplasm.
• Pomegranates are clustered independently from the geographic origins of cultivars.
• A limited differentiation among groups was founded as suggested by values of Gst and Nm parameters.
• The ISSR makers appears a useful tool for studying genetic diversity and its partition.

Genetic diversity of 27 Moroccan pomegranate cultivars from three geographical regions of Morocco was screened using 61 Inter-Simple Sequence Repeat (ISSR) markers. Eight tested ISSR primers generated 70 bands of which 61 are polymorphic (87.14%). Nei's genetic distance ranged from (0.12 to 1) with a mean of 0.67. Nei genetic diversity parameters were 0.35 and 0.32 for Ht and Hs, respectively. Our results show considerable gene flow within and among pomegranate groups and a limited differentiation among groups as suggested by values of Gst (0.08) and Nm (5.80) parameters. The Unweighted Pair Group Method with Arithmetic Mean dendrogram and Principal Component Analysis clustered the pomegranate studied into two main clusters and did not show any relationships with the geographical origins of cultivars. Our results showed that ISSR markers can be a useful tool for detecting molecular polymorphism and studying the genetic diversity of pomegranate genotypes.