Peran Mini-Barcode Internal Transcribed Spacer 2 (ITS2) untuk Identifikasi Molekuler Spesies Anggrek

Abstract

Molecular identification using short orthological DNA sequences (DNA barcoding) has been applied for the classification of orchid species which is a major step in biodiversity management, conservation, breeding, authenticating components of herbal products, and tracking the adulteration of orchid species. One of the most widely used loci for phylogenetic inference at the generic and infrageneric levels in plants was ITS located between 18S rDNA, 5.8S rDNA, and 26S rDNA. The ITS or ITS2 region has been suggested as a plant barcode in some previous studies. However, DNA barcoding using the entire ITS genome is considered less effective and efficient in the process of PCR amplification and sequencing. Besides, complete DNA barcodes are difficult to obtain from herbarium samples and herbal products because some DNA sequences have been degraded. DNA mini-barcodes were developed over the past ten years to overcome issues related to DNA barcoding. DNA mini-barcodes use shorter DNA segments for PCR amplification, so they can identify species effectively and efficiently compared to the regular DNA barcoding. Specific primers that encode the ITS1 and ITS2 regions need to be designed for the PCR amplification. DNA mini-barcoding ITS has proven useful in species identification, classification studies, and authentication of specific orchid species. Therefore, a new rapid identification method based on the ITS mini-barcode is expected to be established, especially for orchid species. Keywords : DNA mini-barcode, Internal Transcribed Spacer, Orchid, Primer Design