Molecular characterization of barley (Hordeum vulgare L.) accessions of the Serbian GeneBank by SSR fingerprinting

Abstract

Molecular diversity of 145 barley (Hordeum vulgare subsp. vulgare L.) accessions from the Serbian GenBank was assessed by single sequence repeats (SSR) markers. A set of 15 SSRs, covering all chromosomes of the diploid barley genome with 2-3 SSR markers per chromosome, with a range of 4-18 alleles per locus were used. In total, 15 loci and 119 alleles were detected, with an average of 7.93 alleles per locus. The Polymorphic information content value ranged from 0.220 to 0.782 with a mean value of 0.534. Regarding the growth habit and row type groups, gene diversity was comparatively higher for the spring (0.616) and six-rowed accessions (0.616) than for the winter and two- rowed accessions (0.322 and 0.478, respectively). Analysis of molecular variance showed that all sources of variation were significant (P < 0.01), but the between-group component was predominant (76.85%) for growth habit and 89.45% for row type. Unweighted Pair Group Method with Arithmetic Mean (UPGMA) cluster analysis based on the shared allele distance (DSA) matrix estimated on the SSR data assigned the genotypes into two clusters - the first smaller consisting of the six 6-rowed spring cultivars and the second comprising six subclusters. Genotype MBR1012 was separated from all other genotypes that constitute UPGMA tree. The associations of genotypes belonging to different growth habit and row type groups were assessed using Principal Coordinate Analysis revealing separation of winter growth habit group from facultative one. The use of the STRUCTURE clustering algorithm allowed the identification of 2 subpopulations of genotypes.