HMW-GS composition and rye translocations of U.S. eastern soft winter wheat and their associations with protein strength

Knowledge of HMW-GS composition and rye translocations of U.S. eastern soft winter (ESW) wheat, and their associations with protein characteristics will be helpful for the identification and selection of genotypes possessing the appropriate gluten strength for wheat-based products. HMW-GS composition and rye translocations of 149 ESW wheat varieties and their relationships with lactic acid solvent retention capacity and SDSS volume were determined. Subunits 2*, 7 + 8 and 2 + 12 are the predominant HMW-GSs in ESW wheat with frequencies of 72.7%, 47.7% and 36.7%, respectively. Two rare subunits, 2^. at Glu-A1 locus and 2+12₁ at Glu-D1 locus, were detected for the first time in ESW wheat, with frequencies of 1.6% and 21.9%, respectively. 1BL/1RS and 1AL/1RS translocations were observed in 18.8% and 10.9% of ESW wheat, respectively. Subunits 13 + 16, 5 + 10, and the absence of 1BL/1RS translocation showed associations with strong protein strength, whereas subunits 2+12₁ were associated with weak protein strength. Four HMW-GS profiles (2*, 7 + 8, 2+12₁), (2*, 7 + 8, 5 + 10), (2*, 7 + 9, 2 + 12), and (2*, 7 + 8, 2 + 12) were predominantly observed in 50.1% of ESW wheat. ESW wheat genotypes carrying subunits 13 + 16 or 7* + 8 at Glu-B1 locus and 5 + 10 at Glu-D1 locus without 1BL/1RS translocation are expected to produce wheat grain containing strong-gluten proteins.