AFLP and SSR Analysis of Genetic Diversity Among Synthetic Wheat Accessions with Resistance to Several Fungal Diseases.

Genetic diversity among 36 synthetic wheat (Triticum sp.) accessions containing different sources of the D genome was assessed using AFLP and SSR markers. Eleven accessions had resistance to Fusarium head scab, nine accessions were resistant to leaf rust, nine accessions were resistant to Helminthosporium leaf blight, and nine accessions were resistant to Septoria diseases. AFLP analysis included 18 EcoRI/MseI primer combinations while the SSR analysis included 27 highly polymorphic SSR markers. Among 745 AFLP fragments scored, 245 were polymorphic across the 36 wheat accessions. Polymorphic information content (PIC) among the accessions for AFLP ranged from 0.05 to 0.50 with an average PIC of 0.24. Major allelic frequency from SSR analysis ranged from 0.20 to 0.83 with an average of 0.47. Number of alleles per locus ranged from 3 to 15 with an average allele number of 7.5. Average gene diversity and PIC for the SSR markers were 0.68 and 0.65, respectively. Cluster analysis showed distinct groups among the wheat accessions studied. Results indicated that the synthetic wheat accessions studied possess a substantial amount of genetic diversity and would be very valuable genetic materials for breeding wheat with resistance to Fusarium head scab, leaf rust, Helminthosporium leaf blight, and Septoria diseases.