Allelic Diversity of Hrd A and Hrd B Hordein-Coding Loci in Wild (Hordeum spontaneum C. Koch) and Cultivated (Hordeum vulgare L.) Barley from Israel and Palestine

Abstract

Polymorphism of hordeins encoded by the Hrd A and Hrd B loci was studied using starch gel electrophoresis in 13 barley landrace accessions and in 31 wild barley populations from Israel and Palestine. In H. spontaneum and H. vulgare, 114 and 11 alleles of the Hrd A locus, as well as 114 and 22 alleles of the Hrd B locus, respectively, were identified. Allele frequencies at the Hrd A and Hrd B loci in the wild barley accessions varied in the range of 0.0019–0.0910 and 0.0019–0.0743, respectively, and in the range of 0.0143–0.4215 and 0.0071–0.200, respectively, in cultivated barley. In the Israeli populations of H. spontaneum and H. vulgare, among 120 alleles of the Hrd A locus, six common alleles were found, and among 135 alleles of the Hrd B locus, only one common allele was detected. At the same time, in H. spontaneum, 18 Hrd A alleles and 15 Hrd B alleles that were found earlier in barley landrace accessions from different countries belonging to or adjacent to the barley center of origin were detected. “Cultural” alleles of the Hrd A and Hrd B loci were found mainly in wild barley populations from the Lake Kinneret region. In the population of H. spontaneum from Susita, the Hrd A3 B162 and Hrd A24 B65 genotypes, which were also found in barley landraces from Syria and Jordan, were identified. In general, analysis of the allelic diversity of hordein-coding loci in the Israeli wild barley populations and the composition and distribution of “cultural” alleles and individual genotypes found in H. spontaneum in barley landrace accessions from 20 countries showed that some populations of H. spontaneum from Israel could have been donors of individual alleles and genotypes of hordein-coding loci for H. vulgare as a result of introgression during spontaneous hybridization in the course of cultivated barley dispersal.