Comparative assessment of SCoT and CBDP markers for investigation of genetic diversity existing in different aegilops species

Objective :

The main goals of this study were investigation of genetic diversity in 103 Aegilops accessions and comparison of the efficiency of start codon targeted (SCoT) and CAAT box-derived polymorphism (CBDP) markers.         

 Materials and methods:

 In this study, the genetic diversity in 103 Aegilops accessions belonging to seven species including seven samples of Ae. caudata, 14 samples of Ae. crassa, 19 samples of Ae. cylindrica, 11 samples of Ae. neglecta, 20 samples of Ae. tauschii, 15 samples of Ae. triuncialis and 17 samples of Ae. umbellulata was evaluated using 15 SCoT and 15 CBDP primers. 

 Results:

 In total, 15 SCoT and 15 CBDP primers amplified 164 and 141 polymorphic bands, respectively. SCoT primers showed the highest values for all of the informativeness parameters than CBDP primers. However, both molecular markers indicated the same PIC values. The results of analysis of molecular variance (AMOVA) revealed that the highest proportion of genetic variance referred to within species. Among all species, Ae. cylindrica had the highest values of genetic parameters. Although cluster analysis based on each marker system classified all accessions into two main groups, the grouping pattern obtained from CBDP data indicated a clear phylogenetic relationship among Aegilops species compared to SCoT data. Besides, the results of clustering were confirmed by principal coordinates analysis (PCoA) analysis.  

Conclusion: 

On the whole, both molecular markers revealed good capability in depicting of polymorphism among tested accessions. However, CBDP markers provided a vivid grouping pattern for evaluated samples. Hence, the use of this technique individually or in combination with other molecular markers is recommended for phylogenetic assessments.