Polymorphism of hordein-coding loci in barley (Hordeum vulgare L.) populations from the countries of Eastern Asia (China, Nepal, Pakistan, India)

Abstract

In this study, starch gel electrophoresis was used to examine polymorphism of hordeins encoded by the Hrd A, Hrd B, and Hrd Floci in 201 accessions of barley landraces from China (including Tibet), Nepal, Pakistan, and India. Altogether, 50 alleles with the frequencies of 0.001-0.2269 were determined for the Hrd A locus, 65 alleles with the frequencies of 0.001-0.1612 were determined for the Hrd B locus, and five alleles with the frequencies of 0.001-0.4537 were determined for the Hrd Flocus. In barley populations from these countries, irregular distribution of alleles and allele frequencies was observed. Cluster analysis of the matrix of allele frequencies in populations from known sampling sites revealed cluster structure of local barley populations within each country. Local populations formed five differently sized clusters in Nepal, four such clusters in India, three clusters in China, and three clusters, in Pakistan. These results suggest that variation and allele frequency distribution of the hordein-coding loci in the countries of East Asia resulted from the introduction and spreading of barley forms through the husbandmen migrations.