Introduction of high molecular weight glutenin subunits 5+10 for the improvement of the bread-making quality of hexaploid triticale

In an earlier study, chromosome 1D of the hexaploid breadwheat cultivar 'Ch inese Spring' was introduced into hexaploid triticale to improve its bread- making quality. That specific chromosome, 1D, carried the a allele at the G lu-D1 locus coding for high molecular weight (HMW) glutenin subunits 2 + 12 , and since subunits 2 + 12 are associated with poor bread-making quality i n wheat, in the present study hexaploid 1D substitution triticale was cross ed with octoploid triticale with the d allele at the Glu-D1 locus encoding HMW glutenin subunits 5 + 10. Following backcrosses to different triticale varieties, 1D substitution lines were established that had Glu-D1 allele a or d in an otherwise genetically similar background, and the influence of t hese two different alleles on bread-making quality of hexaploid triticale w as compared. The agronomic performance of 76 selected lines was evaluated i n a field trial. The Zeleny sedimentation value was determined as a paramet er for bread-making quality, and related to the presence of chromosome 1D, the different glutenin alleles and the nature of the substitution. The pres ence of chromosome 1D had a significant and positive effect on the Zeleny s edimentation value, but the difference between the two glutenin alleles 2 12 and 5 + 10 was not as obvious as in wheat. Owing to its high cytologica l stability and minimal effect on agronomic performance, substitution ID(1A ) appears to be the most desirable one to use in triticale breeding.