genetic linkage map of glu-d1 and allelic variation of hmw glutenin subunits in some iranian bread wheat genotypes

High-molecular weight (hmw) glutenin subunits are encoded by the glu-1 loci (glu-a1, glu-b1 and glu-d1) on the long arms of chromosomes 1a, 1b and 1d. in the present study, we constructed genetic linkage map of glu-d1 and then investigated the allelic variation of hmw glutenin subunits at glu-a1 and glu-d1 gene loci in 30 iranian genotypes using functional markers. glu-d1 was located at 50.8 cm on chromosome 1d and it was tightly linked to wpt-3743 marker (>1 cm). qtl analysis using composite interval mapping detected one significant qtl for grain yield (gy) on chromosome 1d. this qtl (qyld.abrii-1d) was located between wpt-3743 and glu-d1 gene locus. allelic variation of hmw glutenin subunits showed the most frequent alleles were the null allele at glu-a1 and dx2+dy12 alleles at glu-d1loci. the frequency of null alleles or 1 and 2* were 40% and 60% respectively. only 9 genotypes included allelic combination of dx5+ dy10 and the rest of genotypes had dx2+dy12 in the glu-d1 locus. according to the nei's genetic diversity index, alleles at glu-a1 locus have more dispersion in genotypes compared to glu-d1 locus. the cluster analysis of data based on the simple matching coefficient and upgmc methods, classified the genotypes into four groups. six genotypes including: bezostaya, tajan, navid, karaj1, neyshabour, and golestan had ax2* and dx5+ dy10 subunits at glu-a1 and glu-d1 gene loci. identification of genotypes with suitable allelic combinations can be used in breeding programs, especially in hybridization.