Marker-Assisted Selection of High Molecular Weight Glutenin Alleles in Indian Wheat (Triticum aestivum L.) Cultivars and their Correlation with Bread Loaf Volume

Glutenins are polymeric proteins and composed of high molecular weight (HMW) and low molecular weight (LMW) glutenin subunits. High molecular weight glutenin subunit (HMW-GS) plays a key role in determining bread making quality (BMQ). The HMW-GS encoded by Glu-1 loci (GluA1, GluB1 and GluD1) are highly polymorphic. Thus it is very important to identify the alleles at Glu-1 loci for all three genomes for wheat quality improvement. In the present study, Sixty two spring wheat cultivars from five major wheat cultivating agro-climatic zones of India viz., North Western Plains Zone (NWPZ), North Eastern Plains Zone (NEPZ), North Hill Zone (NHZ) Peninsular Zone (PZ) and Central Zone (CZ) were used to investigate the allelic variations for HMW-GS subunits using PCR-based DNA markers. In total, two alleles (Ax2*, Ax1 or Axnull) at Glu-A1, three 4 allele/allelic pairs (Bx7, Bx7+By8, Bx7+By9, Bx17+By18) at Glu-B1 and two allelic pairs (Dx2+Dy12 and Dx5+Dy10) at Glu-D1 were identified using diagnostic DNA markers. Allele or allelic pair Ax2* (66%) at Glu-A1, Bx7+By9 (30%) at Glu-B1 and Dx2+Dy12 (58%) at Glu-D1 were present most frequently in wheat genotypes tested. The effect of interaction of HMW-glutenin allelic combination on Bread loaf volume (BLV) was also analyzed. The allelic combination Ax2*, Bx17+By18 and Dx5+Dy10 exhibited highest bread loaf volume in comparison to other combinations. The marker set used here represents a useful alternative for screening of HMW-glutenin allele (s) for improvement of BMQ in Indian wheat genotypes.