Internal Transcribed Spacer (ITS) and Several Chloroplast DNA Regions of Platycodon grandiflorus (Jacq.) A.DC.
Description
Platycodon grandiflorus (Jacq.) A.DC., belonging to the Campanulaceae family, is a well-known medicinal plant traditionally used as an antitussive, expectorant, and anti-inflammatory agent, and for protecting the respiratory system. In this study, samples were collected from Tan Chu village, Lung Phinh district, Lao Cai province, Viet Nam (22°36'48.2"N 104°17'12.0"E). The plant is a perennial herb, 45- 90 cm in height, with smooth, sparsely branched stems. The root is cylindrical, 5-25 cm long, light yellow to brown, and characterized by distinct longitudinal wrinkles. Leaves are simple or opposite, with serrated margins, dark green on the adaxial surface and covered with a whitish powder on the abaxial surface. The plant bears solitary, bell-shaped purple flowers with a five-lobed green calyx and produces an inverted-ovoid capsule containing numerous small brown seeds (Figure 1). Chloroplast DNA regions are frequently used in phylogenetic and genetic diversity analyses of plants, providing valuable genetic information at various taxonomic levels. The complete chloroplast genome of Platycodon grandiflorus (171,818 bp) has been sequenced and deposited under accession number NC_035624.1 (Hong et al., 2023). Based on nucleotide diversity (Pi) analysis, the ndhC-trnV, ndhF, rpoA, trnK-matK, and trnK-rps16 fragments were selected for primer design (Table 1). Sequencing results revealed that the ndhC-trnV region was 829 bp, ndhF 2232 bp, rpoA 993 bp, trnK-matK 751 bp, and trnK-rps16 690 bp in length. BLAST, BioEdit, and MEGA XII software were employed for sequence alignment and phylogenetic tree construction to support molecular identification.