Towards conservation and breeding of Ajowan (Trachyspermum ammi) by assessing ISSR, morphological traits and germination variability

Ajowan is one of the most important members of medicinal plants of the Apiaceae, consumed by humans. The aim of this study was to explore genetic variability of 20 ajowan populations by ISSR fingerprinting and evaluation of traits at germination. Out of the 30 ISSR primers, ten generated reproducible and polymorphic bands. A total of 93 bands were detected out of which 65 were polymorphic. Highest values for resolving power (Rp) were detected for UBC818 and ISSR5 primers (7.2 and 4.6, respectively) which their sequences had (AC) n or (CA) n motifs. All genotypes were separated in dendrogram drawn by the ISSR data. For all traits measured at the germination stage, there were highly significant differences among genotypes (P≤0.01). A low germination percentage (42.1%) was observed in average. Qom was the best population considering germination properties such as germination percentage (95%) and shoot length (3.8 cm). The highest number of branches and number of umbels were observed for Sabzevar (with 83 and 91, respectively). High broad sense heritability values were obtained for germination and morphological traits (ranging from 0.68 to 0.99). In conclusion, two populations of Sabzevar and Qom populations were the best for several traits and are suggested for further analysis.