Determination of Genetic Diversity in Elite Orchardgrass (Dactylis glomerata L.) Genotypes Using SSR Markers

Abstract

Orchardgrass (Dactylis glomerata L.) is an economically important, and widely cultivated perennial forage grass. The aim of this study was to determine the genetic diversity and genetic relationship among the orchardgrass breeding lines developed in Aegean Agricultural Research Institute, using simple sequence repeat (SSR, microsatellite) molecular markers. The genetic diversity of 32 orchardgrass was assessed using a set of 24 SSR markers. SSR primer pair combinations yielded 126 alleles for all genotypes. The number of alleles per locus ranged from three to seven with an average of 5.25 alleles across 24 loci. The alleles size ranged from 101 to 354 and the polymorphism rate was 100%. Jaccard genetic distance coefficient varied from 0.21 to 0.84 among genotypes. The degree of genetic diversity among the genotypes was high. Total number of rare alleles was 28 alleles across 126 loci. Dendrogram constructed using neighbor-joining analysis based on Jaccard genetic distance matrix were clustered into three main groups A, B and C. Group A was the largest group contained 15 genotypes, while B had 13 genotypes originated mainly from same region. The group C was the smallest group contained genotypes originated from northern part of Turkey. The molecular analysis revealed that a significant genetic variation existed in this orhardgrass collection, and the genotypes studied have potential for ensure rich genetic resources in orchardgrass breeding program. In addition to this, it was concluded that SSR markers are suitable markers for the molecular identification of different orchardgrass genotypes.