He Yang

Ginseng is widely regarded as the “King of Herbs” in traditional Chinese medicine. In recent years, escalating global warming and intensified human activities have led to a continuous rise in environmental temperatures, posing a significant threat to ginseng cultivation in China. Therefore, understanding how high-temperature stress affects the photosynthetic performance of ginseng is essential for developing efficient and sustainable cultivation practices. In this study, four temperature regimes were established to systematically investigate the impact of elevated temperatures on the photosynthetic system of ginseng leaves: 25/16 °C (CK), 30/20 °C, 35/24 °C, and 40/28 °C (day/night). The results demonstrated that high-temperature stress significantly inhibited photosynthesis. Specifically, the activities of key chlorophyll biosynthesis enzymes—porphobilinogen deaminase and delta-aminolevulinate dehydratase—were markedly reduced, resulting in the accumulation of critical intermediates in the chlorophyll pathway, including protoporphyrinIX, Mg-protoporphyrinIX, and protochlorophyll. Chlorophyll synthesis was severely impaired as a result. Consequently, the contents of chlorophyll a, chlorophyll b, and carotenoids declined by 25.38%, 12.52%, and 54.63%, respectively, indicating substantial disruption of the photosynthetic pigment system. Anatomical observations revealed that high-temperatures induced stomatal closure, impairing stomata exchange and further reducing photosynthetic efficiency. Moreover, chloroplast ultrastructure was severely compromised, characterized by excessive accumulation of osmiophilic granules, disorganized and loosely stacked thylakoid membranes, and impaired capacity for light energy capture and conversion. This study provides theoretical insights into the response mechanisms of ginseng leaf photosynthesis under heat stress and establishes a scientific basis for enhancing thermotolerance through breeding programs and improved cultivation management strategies.

Ginseng growth is susceptible to environmental stresses, particularly the frequent occurrence of low temperatures and water fluctuations in spring in Northeast China, which often lead to a decline in medicinal yield and quality. This study systematically analyzed the physiological response characteristics and variation patterns of active components under dual stresses of low temperature and water. The aim was to elucidate the adaptation mechanism of ginseng to abiotic stresses, providing a theoretical basis for optimizing ginseng cultivation management practices and enhancing the quality of medicinal materials. In this study, 2-year-old and 4-year-old ginseng roots were selected as research materials. They were subjected to treatments of low soil moisture (20–30%), medium soil moisture (40–50%), and high soil moisture (60–70%). Low-temperature treatments were conducted at 0 °C for different durations (4 h, 24 h, 33 h, 48 h). Physiological indicators of the ginseng roots were determined at each time point, and the active components of ginseng roots in the control and treatment groups were investigated. The results indicated significant differences in osmotic adjustment substance changes between 2-year-old and 4-year-old ginseng roots. The content of superoxide dismutase (SOD) increased during low-temperature stress in both age groups. An increase or decrease in soil moisture significantly enhanced the accumulation of total ginsenosides. However, low-temperature stress notably reduced the accumulation of total ginsenosides. Nevertheless, after low-temperature treatment, the PPT-type ginsenosides in the high soil moisture group showed a significant increase. The findings of this study provide a scientific basis for improving the medicinal component content of ginseng and offer theoretical support for future water management practices.

Bovine viral diarrhea virus (BVDV) infections are endemic in cattle populations worldwide and cause major economic losses. Thus, an effective vaccine is needed against the transmission of BVDV. The glycoprotein Erns is one of the envelope proteins of this virus and shows BVDV-related immunogenicity. Here, we report the use of Panax ginseng as an alternative production platform for the expression of glycoprotein Erns via Agrobacterium-mediated transformation. Polymerase chain reaction (PCR) and reverse transcription (RT)-PCR analyses showed that pBI121-Erns was stably integrated into the chromosome of transformants. ELISA assay and Western blot analysis confirmed the antigenicity of plant-derived Erns glycoprotein. Immunogenicity was evaluated subcutaneously in deer using a soluble protein extract of dried transgenic ginseng hairy roots. Specific humoral and cell-mediated immune responses against BVDV were detected following immunization. These results demonstrated that the Erns glycoprotein could be expressed in ginseng hairy roots and that plant-derived glycoprotein Erns retained its antigenicity and immunogenicity.