The improvement of the CAPS-marker for St, J and V subgenome identification in Triticeae tribe plants using the 5S non-transcribed spacer polymorphism

In the Triticeae tribe, several subgenomes (St, J, V and others) were described, and a subgenome-specific molecular marker development is an actual branch of studies. Non-transcribed spacers (NTS) of 5S rDNA are perspective to create species-specific or genome-specific molecular markers in closely related organisms. Early, the 5S rDNA NTS based CAPS marker (StJV-f/StJV-r primers with the SmiM1 enzyme digestion) was designed for identification of the St, J and V subgenomes. The V subgenome amplicons were differed from the St and J amplicons in length. The St amplicons were distinguishable from the J amplicons after the SmiM1 enzyme digestion (St fragments were digested, J fragments were not digested, which is a disadvantage, because a failure with the digestion of St amplicons can be mistaken for J amplicons). This article presents the results of the StJV marker improvement. Comparative analysis of restriction enzyme maps revealed that the Hpy166 II enzyme cuts the StJV amplicons of all studied subgenomes in such a way that different product patterns are obtained. Experimental testing confirmed this finding. Thus, the improved CAPS marker can serve as a promising tool for verifying samples in Triticeae plant collections, screening herbarium materials, as well as in the breeding process aimed at improving wheat by involving its wild relatives in traditional breeding programs efficiently.