Association between Grain Quality Traits and SSR Molecular Markers in Some Bread Wheat Genotypes

Improvement of bread quality in bread wheat (Triticum aestivum L.) depends on a thorough understanding of the genetic basis of important quality traits. Therefore, this study was conducted to investigate the genetic basis of wheat grain quality traits including kernel length, kernel width, 1000-kernel weight, grain protein content, Zeleni No, bread volume, moisture content, grain hardness, water absorption and SDS sedimentation volume, and to determine the relationship between the phenotypic data with the genotypic data of four SSR markers using marker-trait association approach. A total of 46 polymorphic alleles with an average of 7.66 alleles per locus were amplified. Polymorphic information content (PIC) of the markers ranged from 0.26 to 0.82, where the first locus for wmc41 (wmc41-1) showed the lowest and the second locus of gwm608 (gwm608-2) indicated the highest PIC. Based on stepwise regression analysis, different markers were entered to the model for kernel length, 1000-kernel weight, bread volume, grain hardness and SDS sedimentation volume. However, for grain protein content, kernel width, Zeleni No., moisture content and water absorption no any marker alleles were detected. For kernel length two marker alleles (gwm608-b5 and gwm644-b4), for bread volume two marker alleles (wmc41-b5 and gwm644-a1), for grain hardness two marker alleles (wmc41-b4 and wmc41-b2) were entered to the model. For 1000-kernel weight and SDS sedimentation volume only one marker alleles of gwm608-b3 and gwm608-b2 for each were respectively detected, which in general, explained from 22% to 37% of the phenotypic variations. The results showed that those markers with high polymorphic content and high genetic variation play a pivotal role in separation and distinction of genotypes.