Molecular marker based analysis of allelic variation in the spring wheat genome

Genetic diversity is the foundation of crop improvement, and the development of new wheat genotypes requires high genetic diversity for successful breeding programs. In this study, genetic diversity and genome-wide allelic variation were assessed by analyzing 100 bread wheat genotypes from a natural population. A total of 189 polymorphic simple sequence repeat (SSR) markers were used, distributed among the A, B, and D homologous genomes. Gene diversity (GD), total number of alleles (TNA), and polymorphic information content (PIC) values were determined based on these markers. The ranking of the three genomes in terms of genetic diversity was as follows: B-genome > D-genome > A-genome. A total of 1219 alleles were identified across the 189 markers, with an average of 6.45 alleles per marker. The highest PIC values were found in markers Xgwm550, Xgwm47, and Xgwm6, with an overall average value of 0.86. The GD values for these markers were 0.88, 0.85, and 0.88, respectively, and they had a total of 14, 12, and 14 alleles. The genotypes exhibited sufficient genetic diversity, with an average polymorphism rate of 92.69%. Population structure and DARWIN analysis revealed that the studied genotypes were divided into five distinct genetic groups These findings provide valuable insights for future association mapping endeavors utilizing this collection of bread wheat cultivars. Cluster analysis using SSR markers further identified specific genotypes, highlighting the potential of SSR markers in studying genetic diversity in spring wheat and selecting desirable genotypes. Overall, these results offer important implications for association mapping and wheat breeding programs aimed at ensuring sustainable food security.