Genetic diversity in European accessions of the Barley Core Collection as detected by isozyme electrophoresis

Genetic diversity in 79 European accessions of the Barley Core Collections was surveyed using isozyme electrophoresis. A total of 26 alleles were obse rved at the ten isozyme loci. All loci were polymorphic except Pgd-1 which was monomorphic. The comparison of the results with those of previous studi es indicates that most of the alleles occurring in the European Barley are also observed in this set of the European Barley Core Collections. Only fiv e alleles (Est-1 Al; Est-5 Ag, Te; Pgi-1 C and Ndh-2 B) were absent. Nine o f 26 alleles were rare alleles, which were detected only in one or two acce ssions. Moreover, most of rare alleles were detected in 6-rowed winter barl ey. It is very important to include rare alleles for maximising the genetic variations in core collections. In the set of European Barley Core Collect ion, 6-rowed barley contained larger diversity than 2-rowed barley; winter type contained larger diversity than spring type. The cluster analysis sepa rated 79 accessions into three major groups. Group I is more complex and co mprised 2-rowed spring, 2-rowed winter and 6-rowed winter barley. In this g roup, 18 accessions in the cluster A and 14 accessions in the cluster B pos sessed identical genotypes as judged from the ten isozyme data. Principal c oordinate analysis could not clearly separate the spring cultivars from the winter barley lines, as well as not separate 2-rowed from 6-rowed barley.