Analysis of Genetic diversity and reltionships in local Tunisian barley by RAPD and SSR analysis

The genetic variation and relationships among 12 local barleys and the varieties Martin and Manel were evaluated using random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR). A high level of polymorphism was found with both RAPD and SSR markers and the mean polymorphism information content (PIC) values were 0.477 and 0.533 for RAPD and SSR markers, respectively. In RAPD analyses, 69 out of 93 bands (74%) were polymorphic. The number of alleles ranged from 4 to 10 per primer, with an average of 6.2 per primer. The RAPD-based genetic dissimilarity (RAPD-GD) ranged from 0.114 to 0.933, with the mean of 0.523. In SSR analyses, a total of 43 alleles were detected, among which 39 alleles (90.7%) were polymorphic. The number of alleles per primer ranged from 2 to 4 with an average of 2.87 alleles per SSR primer. The SSR-derived genetic dissimilarity (SSR-GD) ranged from 0.423 to 0.910, with the mean of 0.665. SSR was better than RAPD in detecting genetic diversity among the barley accessions. A poor correlation (r = 0.193) was found between both sets of genetic similarity data, suggesting that both sets of markers revealed unrelated estimates of genetic relationships. Key words: Barley, RAPD markers, SSR markers, genetic diversity.