Characterization of the VRN-A1 allele introgressed from T. aestivum ssp. petropavlovskyi that influences the heading time in bread wheat

Abstract

Abstract The optimal timing of the heading stage, mainly determined by the VRN genes, contributes to the wide spread of bread wheat and the realization of adaptive and breeding potential. Wild wheat species are valuable sources for expanding the bread wheat genetic diversity by the introgression of new gene alleles, including VRN genes. In this study, a near-isogenic line of the winter wheat cultivar Bezostaya 1 with a VRN-A1 dominant allele was obtained with a T. aestivum ssp. petropavlovskyi accession as the donor. Using known PCR markers for the promoter and first intron sequences of the VRN-1 gene and subsequent sequencing of PCR fragments, the presence of the Langdon deletion was revealed in the first intron (Vrn-A1L allele), previously described only for tetraploid wheat. The allele composition of VRN genes was determined in T. aestivum ssp. petropavlovskyi accessions and the presence of the Vrn-A1L dominant allele was established in all accessions. It was shown that the Vrn-A1L dominant allele increased the shoots-heading period under long- and short-day conditions, which is associated with a prolongation before the first node formation. The comparative study of productivity characteristics of isogenic lines with Vrn-A1a and Vrn-A1Ldominant alleles on spike and plant productivity is presented.