IDENTIFICATION OF RYE CHROMOSOMES INVOLVED IN TOLERANCE TO BARLEY YELLOW DWARF VIRUS-DISEASE IN WHEAT X TRITICALE HYBRIDS

Common wheat x hexaploid triticale hybrids were produced and evaluated for tolerance to barley yellow dwarf virus disease (BYD). The BYD tolerance expression varied with wheat x triticale combination. The selection for BYD tolerance increased the recovery of tolerant genotypes in the next generations. Homozygous tolerant and susceptible lines were obtained in advanced generations. The rye chromosomes 1R, 2R, and 4R with 7R were transmitted as disomic or monosomic, disomic, and double disomic substitution to the late generations of 'Musala' (common wheat) x 'Muskox 658' (triticale), 'Encruzilhada' (common wheat) x 'Nord Kivu' (triticale) and 'Encruzilhada' x 12th. International Triticale Screening Nursery 267 (12ITSN267) (triticale), respectively. A clear association was established between the 1R chromosome of the 'Muskox 658' triticale line and the tolerance to BYDV. Results suggest that the 2R chromosome may be involved in BYD tolerance of 'Nord Kivu' triticale line.