Assessment of the genetic diversity, population structure and allele distribution of major plant development genes in bread wheat cultivars using DArT and gene-specific markers

Knowledge of the degree of genetic diversity can provide fundamental information to breeders for use in various breeding programmes, for instance for the selection of lines with better adaptability. The genetic diversity analysis of 188 winter wheat genotypes demonstrated that this group of cultivars could be divided into four clusters based primarily on geographical origin. The first group contained mostly American and Asian cultivars, while cluster 2 consisted of Central European cultivars, cluster 3 of Hungarian and South European cultivars and cluster 4 mainly of cultivars from Western Europe. Cultivars used in breeding programmes in Central and South East European breeding programmes were found in all four clusters. Wheat genotypes originating from this region of Europe proved to have greater genetic variability than lines from Western and Northern Europe. Among the four clusters, there were also differencies in the frequencies of winter–spring alleles in Vrn-A1, Vrn-B1, Vrn-D1 vernalisation response genes and in the frequencies of sensitive–insensitive alleles in Ppd-B1 and Ppd-D1 photoperiod response genes, which explained the differences in heading date of the four clusters as well.