Evaluation of genetic diversity of native and non-native Dactylis glomerata L. ecotypes using ISSR molecular markers

Orchard Grass (Dactylis glomerata L.) is a perennial forage and cross-pollinating grass, has wide genetic distribution in Iran. Although the genus Dactylis has been studied quite well within the past decades, little is known about the genetic diversity and population patterns of natural populations in grassland regions. The aim of this study is to identify the genetic diversity of this species in the East Azerbaijan, Iran.

In this study, seeds of 25 ecotypes of Dactylis glomerata L. were planted in the research farm of the Agricultural Biotechnology Research Institute of Iran, Northwest & West region in Tabriz as a randomized complete block design with 3 replications. Then 34 selected genotypes (single plant) were examined using 22 ISSR markers.

According to the results of ISSR markers, a total of 424 loci were amplified in the genome, of which 34 loci among all studied genotypes were monomorphic and 390 loci were polymorphic. The mean percentage of polymorphisms for D. glomerata L. in ISSR markers was estimated to be 70.39%. Also, the mean PIC value (polymorphic information content) for ISSR markers was equal to 0.288, the minimum PIC value for ISSR14 marker (0.175) and the maximum PIC value belonged to ISSR22 marker (0.341). Grouping of D. glomerata L. genotypes based on ISSR markers was performed using Mega 4.0.2 and Structure software, which grouped the results of Mega 4.0.2 genotypes into 4 groups, and Structure software grouped the genotypes into 2 groups.

The results indicate that the using of ISSR markers to differentiate close kin populations has a high advantage and plays a significant role in the differentiation of individuals. Also, the high allelic diversity of ISSR markers indicate a large level of diversity in D. glomerata L. populations and it’s a suitable tool for studying the genetic diversity of D. glomerata L.