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چکیده
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The genetic diversity of 34 A. desertorum accessions was studied using 28 ISSR primers. A total of 448 loci were amplifed in the A. desertorum genome, and 402 (90%) of them were polymorphic. The primer (AG)8YC produced the greatest number of polymorphic fragments, while the primer (AC)8YA produced the lowest number. The number of efective alleles ranged between 1.26 and 1.57. The highest value of Shanon index belonged to primer (GA)8T, while the highest value of Nei index (0.33) was detected for primers (GA)8T, (TC)8C, and (GACA)4. Primer (GA)8GCC with PIC = 0.40 was the best informative marker in the evaluation of A. desertorum genetic diversity. Genetic similarity among studied accessions was between 0.45 (G03 and G17) and 0.80 (G01 and G11). Using Bayesian and WPGMA classifcation algorithms, the A. desertorum germplasm was divided into two major subgroups (Red and Green), which consisted of 13 and 17 accessions, respectively, and also admixture accessions. Late-maturing accessions were distinguished from early-maturing accessions and mostly localized in the Green subgroup. The Red subgroup had more private alleles as well as heterozygosity compared with the Green subgroup and therefore also had promising selection potential. Totally, ISSR markers could distinguish early mature genotypes, and this is signifcant for increased forage yield. Likewise, the recognized heterotic groups could help breeders select highly polymorphic genotypes in polycross breeding.
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