Available online 18 September 2025

Panax ginseng (Korean ginseng) is a valuable perennial medicinal herb characterized by its unique storage roots, which develop through an annual growth cycle. Despite its significant agricultural and pharmaceutical importance, the molecular mechanisms driving the seasonal thickening of storage roots remain poorly understood.

This study utilized histological analysis and genome-wide transcriptome profiling to investigate the development of 1-year-old P. ginseng storage roots at early, middle, and late growth stages. Gene ontology (GO) enrichment and network analyses were conducted to identify key signaling pathways. Additionally, the effects of exogenous treatment with storage root development related factors and transgenic Arabidopsis plants overexpressing PgEXP4 were evaluated.

The development of storage roots was characterized by the regeneration, activation and dormancy cycles of the vascular cambium. Early-stage growth was regulated by auxin, gibberellin (GA), and nitrate signaling, promoting cambium regeneration and storage parenchyma cell differentiation. Middle-stage growth involved enhanced cell division, cell wall biogenesis, and secondary growth facilitated by the GA-expansin module. Consistently, transgenic Arabidopsis overexpressing PgEXP4 showed enhanced root growth, suggesting its role in cell expansion during root development. Late-stage growth showed upregulation of jasmonic acid (JA) pathways, indicating their role in preparing for dormancy.

This study elucidates the first-year seasonal growth regulation mechanisms of P. ginseng storage roots, highlighting the intricate hormonal and genetic interactions across developmental stages. These findings provide insights into optimizing ginseng cultivation practices and enhancing crop yields.

Panax ginseng

Storage root

Vascular cambium

RNA-Seq

Hormone

© 2025 The Korean Society of Ginseng. Publishing services by Elsevier B.V.