Morphological and physiological characteristics of seeds from three origins and identification of microbial contaminants in the in vitro cultivation of wild-simulated ginseng

Wild-simulated ginseng has received increasing attention due to its high pharmacological value and morphology and phytochemical similarity to wild ginseng. The objectives of this study were to determine the morphological and physiological characteristics of seeds from three origins, to assess seed viability using the 2,3,5-triphenyltetrazolium chloride (TTC) test, to identify microbial contaminants generated during in vitro cultivation of wild-simulated ginseng, and to develop an effective method for asexual propagation. Seeds were collected from Seosan, Pyeongchang, and Geochang, and their length, width, thickness, and weight were measured. For in vitro cultivation, wild-simulated ginseng seeds were subjected to scarification and GA3 treatments, and the relationship between physiological activity and germination capacity was investigated. Despite high seed viability across all three provenances, no germination was observed after 60 days. To develop asexual propagation techniques, wild-simulated ginseng seeds were cultured in vitro. Approximately 80.2% bacterial contamination and 75.7% fungal contamination were observed during the in vitro cultivation. DNA sequencing identified four bacterial species, including Rahnella laticis, and five fungal species, such as Quixadomyces hongheensis, as the major contaminants. These findings indicate that the identified microorganisms coexist within wild-simulated ginseng seeds. During in vitro cultivation, these microorganisms compete with the seeds for nutrients, thereby hindering germination. Therefore, the application of antibiotics such as penicillin, combined with antifungal agents, is recommended to achieve higher rates of callus induction in the in vitro cultivation of wild-simulated ginseng seeds.