Effect of temperature on growth, biomass accumulation and phytochemical contents of Panax ginseng sprouts cultivated under greenhouse conditions in Thainguyen province, Vietnam

This study evaluated the effects of different temperature regimes (16–26 ± 2 °C) on growth, biomass, and phytochemical composition of Panax ginseng sprouts cultivated in a greenhouse using peatmoss–perlite (1:1) substrate. The experiment was arranged in a randomized complete block design with three replications. Results showed that temperature significantly affected all measured parameters (P ≤ 0.05). The optimal temperature range was identified as 18–22 °C, where plant height, root development, and biomass accumulation reached their maximum values. Ginsenosides and vitamin C contents were also highest within this range. At 24 °C, moderate reductions were observed, while 26 °C caused significant declines in growth and phytochemical accumulation. Severe stress at 28–30 °C resulted in poor survival and negligible productivity. These findings confirm that Panax ginseng is a cold-adapted species and highlight the importance of temperature control for optimizing both yield and quality in greenhouse cultivation systems.