Genetic Diversity and Pathogenicity of Mauginiella scaettae the causal agent of date palm

khamedj is one of the most important fungal diseases that in a favorable condition can lead to severe outbreaks and causing an 80% loss of the annual harvest. 30 isolates of Mauginiella scaettae, the causative agent of this disease including 27 isolates from different locations of the Iran, two isolates from Iraq and one isolate from Kuwait were collected from different palm cultivars during 1397-1397 and used in the present study. Seven EST-SSRs markers were applied to show the genetic diversity among these 30 isolates. Five loci including, SNOD1, SNOD26, SNOD22, SNOD17, and SNOD21 were polymorphic among the species and revealed a total of 16 alleles. Also, two microsatellite markers, including SNOD5 and SNOD16, did not amplify and showed no amplification. The dendrogram constructed based on the similarity index resulted in five major clusters so that two clusters were divided into sub-clusters. The highest similarity value was observed between isolates Ilam-sa and Behb-kh2 (0.75) and followed by isolates abad-ma1 and ramh-sa1 (0.57). On the other hand, two isolates Kheshbid-za and Abad-sa1 have the highest genetic distances with other isolates. Thirteen isolates were selected from the identified genetic groups to study pathogenic groups on the sayer cultivar. The results indicated that there were significant differences among isolates used. The results revealed that Behb-ma1 isolate and Mehr-sa isolate showed the lowest and highest pathogenicity, respectively.