Molecular Cytogenetic Characterization of New Wheat—Dasypyrum breviaristatum Introgression Lines for Improving Grain Quality of Wheat

Hongjin Wang, Hongjun Zhang, Bin Li, Zhihui Yu, Guangrong Li, Jie Zhang, Zujun Yang

As an important relative of wheat (Triticum aestivumL),Dasypyrum breviaristatumcontains novel high molecular weight glutenin subunits (HMW-GSs) encoded byGlu-1Vbgenes. We identified new wheat-D. breviaristatumchromosome introgression lines including chromosomes 1Vband 1VbL.5VbL by fluorescencein situhybridization (FISH) combined with molecular markers. We found that chromosome changes occurred in the wheat-D. breviaristatumintrogression lines and particularly induced the deletion of 5BS terminal repeats and formation of a new type of 5B-7B reciprocal translocation. The results imply that theD. breviaristatumchromosome 1Vbmay contain genes which induce chromosomal recombination in wheat background. Ten putative high molecular weight glutenin subunit (HMW-GS) genes fromD. breviaristatumand wheat-D. breviaristatumintrogression lines were isolated. The lengths of the HMW-GS genes inDasypyrumwere significantly shorter than typical HMW-GS of common wheat. A new y-type HMW-GS gene, namedGlu-Vb1y, was characterized in wheat-D. breviaristatum1Vbintrogression lines. The new wheat-D. breviaristatumgermplasm displayed reduced plant height, increased tillers and superior grain protein and gluten contents, improved gluten performance index. The results showed considerable potential for utilization ofD. breviaristatumchromosome 1Vbsegments in future wheat improvement.