Agropyron elongatum HMW-glutenins have a potential to improve wheat end-product quality through targeted chromosome introgression

After screening of 177 disomic addition lines (DALs) of wheat (Triticum aestivum) containing a pair of chromosomes from different alien species, we found that the chromosome 1E addition line of Agropyron elongatum, that is known to be a potential genetic resource for drought and salinity tolerance, showed potential for improvement of bread-making quality of wheat. This was indicated by increased SDS sedimentation, specific sedimentation, mixograph peak time and SE-HPLC analysis of polymeric proteins. This addition line spontaneously gave rise to a substitution line for chromosome 1D in subsequent generations that showed weak dough strength. Analysis of the x-type HMW-glutenin subunit sequence of Ag. elongatum from DAL1E indicated that it closely resembled the x-type sequence of the A and B genomes of wheat, and the y-type was intermediate between x- and y-type HMW-glutenin subunit genes. From these observations, it was inferred that 1E-encoded seed storage proteins have considerable potential for improvement of wheat end-product quality if transferred to specific chromosomes such as 1A of Chinese Spring (CS) wheat, which has a negative overall effect on bread-making quality.