Functional assessment and SNP-based molecular marker development of two 1S l -encoded HMW glutenin subunits in Aegilops longissima L .

We investigated the functional properties of two 1S l -encoded high molecular weight glutenin subunits (HMW-GS), 1S l x2.3* and 1S l y16*, from Aegilops longissima L . , and developed single-nucleotide polymorphism (SNP)-based molecular markers. Two HMW-GS near-isogenic lines (NILs), HMW-NIL1 (1Ax1, 1S l x2.3* + 1S l y16*, and 1Dx2 + 1Dy12) and HMW-NIL2 (1Ax1, 1Bx17 + 1By18, and 1Dx2 + 1Dy12), were developed by crossing the ‘Chinese Spring’ (CS)- Ae. longissima 1S l /1B substitution line (CS-1S l /1B) with the spring wheat cultivar CB037A, and consecutive selfing combined with selection and identification. Quality analysis of the two NILs showed that the 1S l x2.3* + 1S l y16* subunits conferred better dough rheological properties and breadmaking quality than the 1Bx17 + 1By18 subunits; in particular, they significantly improved dough strength, loaf volume and texture, and final bread score. Allele-specific polymerase chain reaction markers for both genes were developed based on SNP variations and successfully amplified 290-bp and 283-bp specific fragments from the 1S l x2.3* and 1S l y16* genes, respectively. Both SNP-based molecular markers were further validated using 38 wheat varieties, two recombination inbred lines, and four F 2 generations and showed high specificity and accuracy. Thus, these markers can be used for molecular marker-assisted selection in the early generations of wheat quality improvement programs.