Flowchart of the PLUG system. The PCR-based Landmark Unique Gene (PLUG) system extracts primers for wheat by comparing the rice Pseudomolecules database  and wheat UniGene data sets  in an interactive manner. To eliminate paralogous genes, Landmark Unique Gene loci (LUGs) were selected by pair-wise comparisons of the rice cDNA models . TaEST-LUGs were selected as template loci for potential PLUG markers (see Methods). "Html1" and "Html2" are interactive interfaces where the target locus can be selected and primer picking conditions can be inputted, respectively.