Identification of the Scientific Name of Curculigo Orchioides from Kon Ka Kinh National Park in Vietnam, using Morphological and DNA Barcode Methods

Curculigo orchioides is a perennial plant widely used in traditional medicine for its kidney-tonifying, yang-strengthening, warming, dampness-drying, blood-stagnation-dispersing, paralysis-relieving, and tendon-strengthening effects. In Vietnam, there are 7–8 species of Curculigo, some of which are also called Curculigo orchioides but do not possess aphrodisiac properties. This study aims to avoid confusion and accurately identify the species of Curculigo orchioides collected from Kon Ka Kinh National Park using morphological and DNA barcoding methods. Morphological observations focused on describing the stem, leaves, flowers, and fruits. The results showed that Curculigo orchioides hava a short stem covered by overlapping leaf sheaths, with a brown outer layer and a white inner layer. The leaves are sword-shaped with parallel veins, measuring 20–30 cm long and 2–2.5 cm in width. The flowers are yellow, arranged in clusters of 3–5 petals on a short axis at the leaf axils. The capsule fruit is elongated, measuring 1.5–5 cm in length and 0.5–1.1 mm in width, containing 1–4 seeds. The seeds are black, hard, and polyhedral. DNA barcoding analysis revealed clear, intact DNA bands in electrophoresis images. The sequencing results of the rbcL gene segment showed 100% similarity (547/547 nucleotides) to Curculigo orchioides Gaertn., as recorded in the genetic database. Based on morphological characteristics and DNA barcoding, the scientific name of the Curculigo orchioides species found in Kon Ka Kinh National Park was identified as Curculigo orchioides Gaertn., belonging to the family Hypoxidaceae.