Abstract
The objectives of this study were to generate molecular passport data for identification and differentiation of Baltic spring barley accessions (cultivars, landraces and breeding lines) and to estimate the genetic variation within and among these accessions. Allelic profiles of 21 microsatellite and 8 isoenzyme loci were obtained and analysed for 64 Baltic spring barley accessions. The microsatellite data was successfully used to separate all of the accessions by individual allelic pattern and frequencies, whereas only 30 of the studied accessions could be distinguished by isozyme data. Variation was detected both among and within the accessions and was significant. The variation within accessions accounted for 20.6% and 14.3% of the total variation, based on microsatellite and isozyme data, respectively. The six-rowed and two-rowed material was well differentiated by both types of marker data: according to AMOVA this differentiation accounted for 16.9% of the microsatellite variation and 26.8% of isozyme variation. Differentiation of accessions based on the country of origin could be detected only by isozyme markers and accounted for 9% of the total izozyme variation. Both isozyme and microsatellite data showed that accessions of Latvian origin had the highest total diversity values, while material from Estonia was the least diverse.