R-RAP: A new marker for genetic characterization and evaluation of relationships among different Aegilops species

Genetic drift of germplasm in cultivated wheat is good motivation for studying genetic diversity in its wild relatives. In this study, R-RAP, a new retrotransposon-based marker, was applied to assess the structure and genetic diversity of ۳۰ accessions of Aegilops sp. originating from different geographical regions of Iran. The ۱۵ R-RAP primer combinations revealed a total of ۳۳۸ bands ranging from ۱۶ (LTR۱۰۶۱ – OPA۰۲) to ۲۹ (LTR۲۱۱۶ – OPG۰۶), with an average of ۲۲.۵ bands per primer. The size of the amplified bands varied from ۱۰۰ to ۱۵۰۰bp. The total average of polymorphism information content (PIC) was ۰.۳۰. The highest PIC value (۰.۴۶) was for primer LTR۱۰۶۱-OPG۰۶. Of the three studied Aegilops species, Ae. tauschii possesses the highest level of genetic diversity. UPGMA cluster separated the three Aegilops species into three discrete groups. Results show that R-RAP markers could be a reliable marker system for organizing genetic variability and detecting useful diversity for wheat breeding purposes. The different diversity parameters calculated in this study demonstrated the high diversity present in Aegilops accessions.

Keywords:

Aegilops , Genetic variability , polymorphism information content (PIC) , R-RAP markers