The rbcL and matK regions have been proposed as the "core barcode" for plants and the ITS2 and psbA-trnH intergenic spacer (PTIGS) regions were later added as supplemental barcodes.  ...  DNA barcoding technology, which uses a short piece of DNA sequence to identify species, has wide ranges of applications. Until today, a universal DNA barcode marker for plants remains elusive.  ...  The psbA-trnH intergenic spacer (PTIGS) region has been successfully used to resolve problems in species identification in a number of studies [3, [7] [8] [9] [10] .  ...