Comparative analysis of the genetic diversity dynamics at gliadin loci in the winter common wheat Triticum aestivum L. cultivars developed in Serbia and Italy over 40 years of scientific breeding

The dynamics of genetic transformations at gliadin-coding loci in the winter common wheat cultivars produced in Serbia and Italy over 40 years of scientific breeding was studied. It was demonstrated that a number of alleles unique for the wheat cultivars of each country were substituted with the alleles of a limited number of donor cultivars, in particular, cultivar Bezostaya 1 and its derivatives. On the background of preserved heterogeneity values during various time periods of breeding in each country, the genetic diversity in the total region decreased, as demonstrated by similarity in the sets of alleles of gliadin loci and their frequencies in the modern cultivars of these two Southern European countries. This decrease in the genetic diversity is an erosion of genetic resources within the region, which results in a loss of unique coadapted gene complexes.