Molecular markers & plant breeding
Amin Azadi; Saeedeh Khani Bafrouei
Abstract
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-D1and then investigated the allelic variation of HMW glutenin subunits at Glu-A1 and Glu-D1 ...
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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-D1and 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-A1and 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.
Plant breeding for abiotic & biotic stresses
Mahnaz Rahmati; Mohsen Mardi; Mohammad-Reza Naghavi; Eslam Majidi Heravan; Babak Nakhoda; Amin Azadi; Ghasem Mohammadi-Nejad
Abstract
In order to identify yield and yield component QTLs under control and salt-stress conditions, a population of 254 recombinant inbred lines (RILs), derived from a cross between two bread wheat cultivars, (Roshan / Sabalan), was assessed. Parents and their 254 recombinant inbred lines (RILs) were evaluated ...
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In order to identify yield and yield component QTLs under control and salt-stress conditions, a population of 254 recombinant inbred lines (RILs), derived from a cross between two bread wheat cultivars, (Roshan / Sabalan), was assessed. Parents and their 254 recombinant inbred lines (RILs) were evaluated in an alpha-lattice design with two replications in two control and saline environments of Yazd in 2011-2012 cropping season. Yield and yield-related traits were evaluated at harvest time. The genotyping was carried out using SSR and DArT markers. A, B and D genomes were covered by 411.8, 620.4 and 67.5 cM, respectively. Also, a total of 48 QTLs were detected on 11 chromosomes for grain yield, biological yield, harvest index, thousand-kernel weight, grain number per spike, spike weight and spikelet number per spike. Roshan (salt tolerance) alleles were associated with an increase yield under saline conditions. SSR markers including gwm146, gwm577, gwm249 (on chromosomes 2A and 7B) were tightly associated with different QTLs. The major effect QTLs were located on chromosomes 1A and 7B for grain yield, harvest index and spike weight, which were explained 10.2%, 12.98% and 29 % of the total phenotypic variance, respectively. These QTLs and markers could be suitable for marker-assisted selection and gene stacking techniques. Moreover, co-located QTLs were detected on chromosome 2B for evaluated traits.