Genome-wide Identification and Characterization of Interspecific Introgressions of Bread Wheat Genetic Material into Homeologous Chromosomes of Durum Wheat

Abstract

The hexaploid bread wheat Triticum aestivum L. (2n = 6x = 42) and the tetraploid durum wheat Triticum durum (2n = 4x = 28) are two commercially the most important wheat species worldwide. These two species are components of the same gene pool, which evolved under different conditions, which made it possible to acquire different adaptations to a wider range of environmental conditions. Identification and characterization of introgressed fragments of one species in the genome of another can help in the search for new loci responsible for economically valuable traits. Single nucleotide polymorphism (SNP) microarrays provide information on the genotypes of thousands of positions throughout the genome. This information can be used to obtain the distribution of alleles of one species in the genome of another and to determine the location of introgressed fragments. In our work, we used genotyping data from the SNP microarray to identify durum wheat chromosome fragments containing bread wheat alleles in the offspring from crossing bread and durum wheat. We have studied the distribution of the genetic material of bread wheat in 15 combinations from crosses of bread and durum wheat. Introgressed fragments of bread wheat into the durum wheat genome were identified on chromosomes 1A, 1B, 4A, 5B, 6B, and 7A. The introgressed fragments showed polymorphism in different breeding lines. A functional enrichment analysis of genes in the introgression fragments showed the presence of statistically significant enrichment of genes responsible for various molecular functions, biological processes and cellular components. The obtained data can be used to identify new QTL of economically valuable traits for obtaining durum wheat varieties with improved agronomic traits.