The diversity of bread wheat landraces from Asia and synthetic hexaploid wheat by alleles of loci linked to the SKr gene – a suppressor of crossability of bread wheat with rye

Hybridization of bread wheat (BW) with rye is one of the ways to enrich its gene pool. The main control of crossability of BW with rye is carried out by the suppressor SKr. Previously, we demonstrated diagnostic efficiency of marker loci cfb341, TGlc2, gene12 and gene13, closely linked to SKr, for searching BW accessions in the VIR collection with high/low crossability, and identified new alleles of these loci in accessions from Eastern Siberia and Pakistan. In order to expand the search for rye-compatible accessions, a set of 108 BW landraces from Asia was studied. The accessions from Mongolia, Pakistan, India were the most polymorphic on marker loci, while the least polymorphic were from Turkey and Iran. In total, eight haplotypes were identified based on allelic composition of the loci, one of which was new. Accessions with haplotypes containing rare/new alleles were distributed into groups, which on their origin corresponded to the main routes of BW spread from Western to Eastern Asia. Rye-compatible forms were not only in China and Japan, but also in Pakistan, Mongolia, Afghanistan. As a new source of diversity for BW, 30 synthetic hexaploid wheat (SHW) accessions were studied, in which the SKr gene was also involved in controlling crossability with rye. Many SHW had high crossability but were less polymorphic on marker loci than BW. However, the used DNA-markers were not as effective in identifying SHW with high/low crossability, that may point to the involvement also of other genes in controlling this trait. Identified rye-compatible accessions BW and SHW with а allele-trait association can be used as new sources in fundamental research and in breeding.