Deployment of either a whole or dissected wild nuclear genome into the wheat gene pool meets the breeding challenges posed by the sustainable farming systems

Abstract

Deploying whole and dissected nuclear genome of wild Triticeae species in the homoeologous wheat genetic background through inter-specific hybridization and introgression is a lower cost and effective option to prepare wheat germplasm with unexploited genes for disease resistance and enhanced grain yield and quality traits. The whole nuclear genomes of Dasypyrum villosum (Dv) and T. turgidum var durum have been combined, and an homoploid derivative of the original amphiploid displayed typical ‘farro’ spike morphology, tough rachis and the adaptive traits of Dv such as high resistance to diseases (caused by Tilletia tritici, Blumeria graminis f. sp. tritici, Puccinia triticina and P. graminis f. sp. tritici), heading earliness and fortified caryopses (high protein and micronutrient contents). The dissection of the Dv genome by either ‘Triticum aestivum cv Chinese Spring (CS) × hexaploid amphiploid’ or ‘(CS × Dv) × CS’ hybridization and backcrossing provided wheat introgression breeding lines (IBLs) expressing one or more of the Dv adaptive traits. Molecular analyses revealed that either cryptic or Genomic In-situ Hybridization (GISH) detectable Dv chromatin introgression occurred in those IBLs. The IBLs, after 2 years of low-input field tests and genetic analyses in Italy and Hungary, showed simple inheritance, dominance and stability of the adaptive and disease resistance traits.