Lonicera japonica Thunb has significant edible and medicinal value, possessing heat clearing, detoxification, antibacterial, and blood pressure reduction properties. Currently, its quality is constrained by factors such as climate, environment, flowering period, and germplasm degradation. The strategy of using bioreactors and abiotic inducers to produce bioactive metabolites has not yet been implemented. This study reports, for the first time, the induction of an embryogenic callus from L. japonica anthers, the identification of tissue morphological structures, and the effects of light induction on the callus morphology, metabolite accumulation, and antioxidant activity. The results showed that the MS medium, supplemented with 1.0 mg·L⁻¹ 6-BA, 1.5 mg·L⁻¹ NAA, 1.5 mg·L⁻¹ 2,4-D, and 0.2 mg·L⁻¹ KT, induced 89% embryogenic callus formation. Uniform callus lines were obtained using 2.0 mg·L⁻¹ 6-BA, 0.5 mg·L⁻¹ NAA, and 0.2 mg·L⁻¹ KT in each subcultivation. Embryogenic cells were observed to have closely arranged spherical protruding granules on their surface, along with visible nuclei and numerous starch grains. After 15 days of blue light induction, active metabolites and antioxidant activities peaked. This experimental system not only provides support for germplasm innovation but also indicates that abiotic inducers can be utilized as a means to achieve higher yields of metabolic products.

Drought stress during the Codonopsis pilosula (Campanulaceae) seedling stage significantly affects its growth, quality, and yield. The aim of this study was to identify drought-tolerant cultivars of C. pilosula by using the growth—physiology—yield composite index (GPYCI) and drought-tolerant indices. Nine C. pilosula cultivars were evaluated under normal-watered (black plastic film hole sowing, BF) and water-stressed (spread in the open field, SF) conditions in a design that adopted a two-factor paired experiment with three replications. The emergence rate was significantly influenced by the water treatment, while both the water treatment and the cultivar affected root length, proline content, APX activity, and chlorophyll levels. The G1 cultivar performed better than others in multiple aspects. Yields and their attributes varied among cultivars under different water levels. The average yield was 7350.76 kg/hm² under BF conditions and 4856.32 kg/hm² under SF conditions. Drought stress reduced the total root length, single root fresh weight, and yield by 18.33%, 28.4%, and 33.9%, respectively. Correlation analysis revealed unique physiological response mechanisms to water changes among cultivars. Drought tolerance indices and comprehensive factor analysis indicated varying levels of drought tolerance among cultivars. This study has provided valuable insights into the growth, physiology, and yield response of C. pilosula under drought conditions and laid the foundation for breeding drought-tolerant cultivars.

In recent years, global climate change, combined with increased human activities, has led to habitat degradation and range shifts in rare medicinal plants, potentially affecting the quality of medicinal herbs. In this study, we assessed how key environmental variables shape the potential distribution of Apocynum venetum L. based on 281 wild occurrence records and nine environmental variables using the MaxEnt model. The results revealed that the mean temperature of the coldest quarter, solar radiation in June, and elevation are the most significant factors affecting the distribution of A. venetum, with optimal values ranging from −10 to 5 °C, 21,000 to 23,000 kJ m⁻² day⁻¹, and 200 to 1500 m, respectively. Ecological niche modeling indicated that highly suitable habitats are primarily located in Xinjiang, Gansu, Shaanxi, Shanxi, Henan, Hebei, Jiangsu, Shandong, and Inner Mongolia. However, future projections under climate change suggest an expansion of these suitable areas, shifting towards higher latitudes in the northwestern regions and high-altitude mountains. These findings provide a scientific basis for guiding the production and sustainable utilization of A. venetum resources.