Evaluating ITS barcode as a molecular tool for determining orchid protocorms genetic identity

Orchidaceae, one of the largest families of flowering plants, includes numerous endangered species. Identifying orchid species, especially those with fertile parts, poses significant challenges. In this study, a molecular analysis based on sequence analysis of the internal transcribed spacer (ITS) region of ribosomal DNA was used to determine the genetic identity of protocorms found in the main habitat of 4 co-occurring orchid species in Samsun/Türkiye. We collected 100 protocorms from the soil of the main habitat during the vegetative stage. Then, an aligned sequence of the complete ITS region was obtained using the universal primers ITS1/ITS4 to determine the genetic distances and the phylogenetic tree. As a result, the sequence of the protocorms aligned very closely with the sequence of Orchis provincialis. ITS has proven a useful DNA barcode for distinguishing orchid protocorms from different orchid species. Nevertheless, additional DNA regions are necessary to expedite research and conservation efforts for radiated orchid species.