Introduction

Medicinal plants play a crucial role in China’s economic and social development because they are valuable health resources. Further, they have considerable economic potential, offer a range of scientific and technological advantages, have strong cultural value, and contribute to the preservation of the environment (Chen et al. 2021). Guizhou Province has abundant wild medicinal plant resources, with approximately 226 species spanning 97 families and 197 genera. Local inhabitants rely heavily on these medicinal plants for their healthcare needs, thereby demonstrating a deep understanding of their distribution and their potential for disease prevention and treatment (Chen et al. 2023b). In Central Europe, approximately 100 medicinal plants have a long history of continuous use, particularly in cardiovascular protection and tonics (Dal et al. 2022). Medicinal plants have a significant effect on disease treatment. For instance, Rhodiola rosea, a medicinal plant, has demonstrated efficacy in relieving pain, treating gout, and resisting cold, and has shown promise in the treatment of rheumatoid arthritis in numerous clinical studies (Ma et al. 2021). Traditional Chinese (Mongolian) medicines such as Atractylodes chinensis (DC.) and Pogostemon cablin (Blanco) Benth played an important role in the fight against the novel coronavirus (Shi et al. 2019). Medicinal plants have not only demonstrated effectiveness in disease treatment, but also offered advantages in the context of dietary and healthcare measures. Flavonoids, widely found in the roots, stems, and leaves of medicinal plants, exhibit antimicrobial properties and potential health benefits (Sun and Shahrajabian 2023). Medicinal plants have a profound impact on both clinical settings and life. China has implemented a series of policies to effectively promote the development of its medicinal plant industry. The implementation of the “Healthy China 2030” Plan has increased the use of Traditional Chinese Medicine (TCM) as a national strategy. Policies such as the “Plan for the Protection and Development of Chinese Materia Medica (2015–2020)”, the “Outline of the Strategic Plan for the Development of TCM (2016–2030),” and the “Chinese Materia Medica Industry Poverty Alleviation Action Plan (2017–2020)” have played a key role in improving the medicinal plant industry from various perspectives. With the improvement of living standards and increasing incidence of diseases, the public’s awareness of disease prevention has also increased, which has driven the growing demand for medicinal plants (Chandra et al. 2021).

Medicinal plants have a rich history in China, dating back to the Qin and Han Dynasties when they were exported to Southeast Asia. The Silk Road played a pivotal role during the Tang and Song Dynasties, facilitating the exchange and prosperity of medicinal plants. In the Ming Dynasty, China’s trade in medicinal herbs and medical technology peaked, was exported to East Asia and Western Europe (Hou and Li 2021). However, the importance of medicinal plants has gradually diminished in modern China. To address this situation, China introduced the concept of the “internationalization of Chinese medicine” in 1996. This concept explores the potential of medicinal plants to increase their import and export scales, promote sustainable development, and establish their legal status overseas (Lin et al. 2018). Recent data from the National Bureau of Statistics (http://www.stats.gov.cn/sj/) show that the turnover of domestic medicinal plants has increased, and the export of Chinese medicine patents has increased.

However, due to the lack of standardized quality system for medicinal plants and cultural differences, the progress of ‘internationalization of traditional Chinese medicine’ is slow. Therefore, it is crucial to improve the quality of the production process, as the value chain of medicinal plants is an important link connecting the production, processing, circulation and consumption of medicinal plants. It plays a vital role in adding value to products and aligning the interests of stakeholders throughout supply and marketing processes. The value chain also accelerates commercialization, drives industrial transformation, and enables industrial upgrades and development. Exploring the value chain can positively influence the strategic use of medicinal plants and the overall agricultural sector.

Focusing on the links in the value chain, this paper aims to analyze the factors affecting the survival and development of medicinal plants from sowing to harvesting and processing, covering aspects such as land selection, climate change, the characteristics of the medicinal plants themselves, and the selection of germplasm resources (Fig. 1). The results of this paper could lay the foundation for promoting the development of medicinal plants and revitalizing TCM.

Fig. 1
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Schematic diagram showing the production process of medicinal plants

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Literature search

For this section, article retrieval was conducted on the Web of Science database using the term “medicinal plants”, covering the period from January 2013 to December 2023. Using the Citexs data analysis platform (https://www.citexs.com), a data visualization analysis was performed based on country, keywords, publication volume, and publication institution. A total of 54,640 English articles were obtained.

Overview of the annual publication of articles

Since 2013, the number of articles published on medicinal plants has continued to increase yearly. In 2016, China formulated a policy, named the “Health China 2030 Strategic Planning Outline,” to increase the role of medicinal plants in medical treatment. Similarly, the issuance of the “14th Five-Year Plan for the Development of Traditional Chinese Medicine” in 2022 has resulted in a new era with a steady increase in the use of medicinal plants. The spatial area of medicinal plants in cultivation has continued to increase, and the planting of medical plants has continued to increase in cultivation. Meanwhile, researchers have further studied the medicinal properties, efficacy, and clinical applications of medicinal plants. In this context, the chemical synthesis of medicinal components and molecular pharmacognosy have gradually become more mainstream. The number of research articles on medicinal plants published is expected to peak by 2022, reaching 8101, accounting for approximately 14.83% of the total number (Fig. 2).

Fig. 2
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Statistical chart of Number of articles published on “medicinal plants” from 2013 to 2023

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National statistics of publications on medicinal plants

The number of papers published in the field of medicinal plants in certain countries from January 2013 to December 2023 is shown in Fig. 3. China has a total of 10,263 published papers in this field, accounting for 18.63% of the global total.

Fig. 3
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Map of articles published on “medicinal plants” by country from 2013 to 2023

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Analysis of keywords and focus areas

Keywords analysis reflects topic evolution trends and research focus areas. With “medicinal plants” as the search term, a total of 54,640 articles in English were obtained from the Web of Science database. The time span was set from January 2013 to December 2023, as shown in Fig. 4. The five keywords with the highest frequencies were ethnobotany, antioxidant, in vitro, extract, and antioxidant activity. Through keywords hotspot analysis, most current studies on medicinal plants have explored their drug constituents and effects, and it is difficult to summarize the factors related to growth and development. Therefore, this paper considered the value chain as the research object and analyzed each chain to examine the factors affecting the development of medicinal plants use.

Fig. 4
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Schematic diagram of keyword analysis from 2013 to 2023

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Through these literature searches related to medicinal plants, it was found that there is currently no value chain perspective on the impacts affecting medicinal plants. Therefore, this formed the focus of this paper. The value chain of medicinal plants includes inputs, production, sales, and other links. Among them, the production process determines the quality of products and the smooth development of the medicinal plant value chain. The production chain includes selecting the planting area, seeding, field management and harvesting.

Influence of endogenous factors on the distribution and metabolism of medicinal plants in cultivation areas

The extensive destruction of wild medicinal plants has led to the scarcity of wild resources. The cultivation of medicinal plants has certain limitations. Land salinization, soil properties, and climatic factors can lead to the loss of medicinal plant habitats and have a negative impact on cultivation conditions. To date, 33% of the world’s soil has been contaminated and the frequency of extreme weather events is increasing substantially. In the early 1960s, global temperatures were expected to rise by 4 °C (Betts et al. 2011). Meanwhile, extreme weather conditions, such as the floods in 1998 and the drought in 2018, led to a decline in crop yields (Oort et al. 2023). Therefore, it is important to select a suitable environment for the survival and development of medicinal plants.

Influence of land selection on the growth and secondary metabolism of medicinal plants

The choice of planting area is the first element affecting the survival and development of medicinal plants. The soil where medicinal plants grow guarantees their survival. Therefore, the selection of a suitable soil environment is particularly important to ensure the quality of medicinal plants. Different soil textures affect the growth and development of peanuts. Sandy soil is favorable for increasing the aboveground biomass of peanuts in the early stage and loamy soil is favorable for increasing the aboveground biomass in the late stage. Clay soil conditions can reduce water loss, but are unfavorable for the accumulation of dry mass in the underground parts of the plant (Zhao et al. 2015). Soil texture affects the growth of medicinal plants and has a corresponding effect on the content of secondary metabolites in plants. Ginger (Zingiber officinale), a medicinal and edible plant, has shown a correlation between secondary metabolite content and soil texture. Sandy soils reduce its secondary metabolites compared with clay soils (Setyawati et al. 2021). However, soil physicochemical properties also have an impact on the growth, development, and secondary metabolism of medicinal plants. As a traditional medicinal plant in the Americas, Ambrosia artemisiifolia is particularly sensitive to Potential of hydrogen (pH) during its growth. When the pH value is 7, the leaves grow and develop slowly, and the plants cannot flower and pollinate. Meanwhile, the pH value is 5, the plant produces more pollen (Gentili et al. 2018). Soil bulk elements and trace elements also determine whether medicinal plants are suitable for on-site planting. Therefore, Lv et al. conducted a joint analysis of soil physicochemical properties, elemental contents, and Ligusticum sinense ‘Chuanxiong’ medicinal constituents in L. chuanxiong-producing areas. Based on the soil element data, suitable areas of L. chuanxiong origin were determined (Lv et al. 2021). Thus, the selection of suitable land is particularly important for introducing medicinal plants for cultivation and relocating them for conservation purposes.

Effects of environmental factors on medicinal plant distribution

Environmental change is also an important factor in the sustainability of medicinal plants. Manish et al. performed a predictive analysis of current and future climatic environments to examine the impact of the Himalayan climate on 163 species of local medicinal plants. The results of the study show that the most of the species will move northward under future climates (Manish. 2022). Meanwhile, 13–16% of medicinal plants may lose their existing potential habitats. Fritillaria cirrhosa and Lilium nepalens are valuable medicinal plants in Nepal. Researchers have predicted the distribution of these two species under climate change and the results have shown that these species will move to the northwest. By 2050, they will lose their habitat in hills and low mountains (Kumar et al. 2017). Indonesia is also rich in medicinal plant resources, and Cahyaningsih et al. conducted medium-term and long-term projections of medicinal plant distribution areas under two climate change scenarios. The abundance of medicinal plants showed a decreasing trend, and more than half of the medicinal plants lost 80% of their distribution areas, with islands such as Papua and Java showing the greatest reduction in the distributions of medicinal plants (Cahyaningsih et al. 2021).

Using the Biomod2 platform and ArcGIS (10.8) spatial analysis, we predicted the distribution of Paeonia lactiflora Pall. and suitable future habitats by considering the environmental factors. Under future climatic conditions, the suitable distribution area for P. lactiflora Pall. gradually decreased, with the trend of the most suitable distribution center shifting from the northeast to the southwest (Bi et al. 2022). Similarly, Guo et al. used the MexEnt model to analyze the geographic distribution of Fritillaria cirrhosa D. Don under environmental changes. The results showed that the suitable area for F. cirrhosa D. Don was significantly reduced under future climatic conditions (Guo et al. 2018). These findings reflect the challenges of understanding the environmental factor changes influencing the distribution of medicinal plants.

Effects of environmental factors on secondary metabolites and medicinal plant yield

Environmental factors also affect the secondary metabolism and yield of medicinal plants. In the context of global warming, the global demand for atmospheric evaporation has increased substantially. This poses a considerable threat to the survival of medicinal plants, especially in arid and semi-arid regions (Vicente-Serrano et al. 2022). High temperatures and droughts have also led to a decrease in the photosynthesis of crops, which impedes crop growth and yield (Qaderi et al. 2010; Amiri et al. 2015).

Effects of drought on medicinal plants

Drought stress causes a decrease in starch content and an increase in sucrose content in most plants. However, the downregulation of the expression of related genes may be one reason for the decrease in biomass and yield (Cui et al. 2019). Withania somnifera (Linnaeus) Dunal, a common medicinal plant, is susceptible to drought stress. This has resulted in the depletion of reducing equivalents of CO2 absorbed by its Calvin cycle, and has simultaneously led to a decrease in the consumption of substances during primary metabolism and the allocation of carbon fluxes from primary to secondary metabolic pathways. This in turn has led to the accumulation of plant sterols and has promoted plant secondary metabolism (Singh et al. 2018). Therefore, appropriate drought stress conditions favor the accumulation of secondary metabolites in medicinal plants.

Caser et al. studied the secondary metabolites of Salvia dolomitica Codd under drought stress. As its secondary metabolites, sesquiterpenes were regulated in all genes related to sesquiterpene metabolism under drought stress. This resulted in sesquiterpene accumulation and the enhancement of its medicinal constituents (Caser et al. 2019). Zhang et al. used phosphoproteomics to examine the phenolic and terpene content of S. dolomitica Codd under drought conditions. The results have shown that drought stress affected the phenol and terpene contents in Salvia divinorum under drought conditions (Zhang et al. 2022a, b, c). Under drought conditions, the terpenoid content was affected in Bupleurum chinense DC. roots (Yang et al. 2022b), in the trichomes of tobacco leaves (Wang et al. 2021b), and in Catharanthus roseus (L.) G. Don (Liu et al. 2017). Terpenoids are regulated by drought stress, but the content of flavonoid and alkaloid will also increases. The content of phenolic compounds is upregulated in drought-tolerant plants but decreased in drought-sensitive plants (Liu et al. 2023).

Drought stress can affect the metabolic process of plants and reduce the biomass of medicinal plants. Matriaria recutita L. is a medicinal plant with some drought tolerance. However, drought still leads to reduction in plant height, flower number yield, and the weight of the aboveground parts (Baghalian et al. 2011). Drought also leads to a decrease in leaf water content and chlorophyll content. This in turn, significantly reduced the biomass of Dendrobium moniliforme (Wu et al. 2016a, b). Khorasaninejad et al. found that the growth parameters of Mentha canadensis Linnaeus were significantly affected by drought stress conditions. The fresh weight of the aboveground portion of the mint, the dry weight of the roots, and the biomass were significantly lower than those of normal plants (Khorasaninejad et al. 2011). Drought is one of the key influences on the growth and development of medicinal plants. However, the frequency of atmospheric and soil drought is increasing with the prediction of the future climate (Qaderi et al. 2023).

Effects of high temperatures on medicinal plants

High temperatures are another important climatic factor affecting the growth and development of medicinal plants. Under different scenario simulations, the rate of global warming was found to be slightly higher than the current temperature (Wu et al. 2022). High-temperature stress in medicinal plants is mainly characterized by internal plant physiological changes, such as an increase in the content of antioxidants such as superoxide dismutase, catalase, or reactive oxygen species. Meanwhile, high temperature also leads to changes in plant biochemistry, such as protein denaturation in plant metabolism (Ncube et al. 2012). These are ultimately manifested in altered phenotypes and yields of medicinal plants. High-temperature stress inhibits photosynthesis in peonies, and with the passage of time weakens photosynthesis, destroying its photosynthetic system and impeding primary metabolic processes (Ji et al. 2022). However, high-temperature stress promotes the accumulation of some secondary metabolites. Heydari et al. subjected two peppermint species, Mentha x piperita L. var. Mitcham, and Mentha arvensis var. piperascens Malinv. to high-temperature stress. The results showed that menthol content decreased with increasing temperature. However, menthone and menthol acetate showed increasing trends (Heydari et al. 2018). Panax ginseng leaves under high-temperature stress have shown premature senescence, resulting in less carbon accumulation owing to the inhibition of photosynthesis. However, the ginsenoside content is higher under high-temperature conditions than under low-temperature conditions (Jochum et al. 2007).

Moderate drought and high temperatures have a certain inhibitory effect on the primary metabolism and physiological and biochemical reactions of medicinal plants. However, they are favorable for the secondary metabolism of medicinal plants and ultimately improve their medicinal efficacy. This is mainly because carbon fixed by photosynthesis is used to synthesize secondary metabolites (Mahajan et al. 2020). However, climate change cannot be reversed in a relatively short time scale. Therefore, it is particularly important to analyze the response mechanisms of medicinal plants to different stress environments. The increase of carbon dioxide (CO2) concentration in the twenty-first century is one of the factors leading to the rise of global temperature. (Muhammad et al. 2023). However, so far, there have been relatively few studies conducted on the effects of CO2 on medicinal plants and the underlying mechanisms have not yet been clarified.

Limitations on the development of medicinal plants use due to continuous cropping obstacles

The growth characteristics of medicinal plants are one of the most important obstacles to their survival and development. There is a dialectical and unified relationship between the survival and health of medicinal plants and environmental factors. However, medicinal plants also face limiting factors, such as continuous cropping obstacles (CCO). CCO refers to the continuous cultivation of the same plant in the same cultivated land for a long time or continuously. Even if suitable nutrient and field management measures are provided, the plants may remain weak, and the yields, resistance, and frequency of pests and diseases increase (Zhang et al. 2007). Therefore, CCO is a limiting factor in the development of medicinal plants. Medicinal plants tend to absorb certain soil nutrient elements. The long-term cultivation of a single medicinal plant leads to an imbalance in the level of nutrients in the soil, resulting in an extreme scarcity of certain types of elements. Then, the ability of plants to absorb and utilize the remaining nutrients will be weakened. This leads to soil acidification and salinization, changing the physicochemical properties of arable land. It can also lead to an increase in harmful microorganisms in the soil, which can lead to the occurrence of plant diseases. Simultaneously, plants secrete self-toxic substances through chemosensitization, which inhibits water and nutrient absorption by the root system (Fig. 5).

Fig. 5
figure 5

Effects of continuous cropping obstacles (CCO) on medicinal plants. (a) CCO affect plant physiological and biochemical responses; (b) CCO change the physical properties of soil; (c) plants produce root secretions; (d) altered microbial distribution; (e) altered efficiency of nutrient uptake and ion ratio

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Effects of continuous cropping on the microecology of medicinal plants

Amomum villosum Lour. (Wang et al. 2022a), Panax quinquefolius L. (Li et al. 2021), Coptis chinensis Franch. (Alami et al. 2021), and Piper nigrum L. (Wu et al. 2015a) are important medicinal plants in China, and continuous cultivation can result in continued impacts on crop health. Therefore, the enzyme activity in the soil and the physical and chemical properties of the soil undergo a substantial degree of change. However, these effects depend on the plant species and cultivation time. After 2 years of continuous cultivation of Aconitum carmichaelii Debeaux, the NO3−, K+ and other ions in the soil increased compared with the control group. Ca2+, Mn2+, and other metal particles showed a decreasing trend (Fei et al. 2021). A comparison of Panax quinquefolius L soils with different numbers of years of cultivation showed that continuous cultivation of P. quinquefolius L. significantly increased the activity of neutral phosphatase. Meanwhile, the activities of alkaline phosphatase and cellulase were significantly reduced (Liu et al. 2021a, b, c). Li et al. studied the soil of P. quinquefolius L. grown for 10 years and the soil of uncultivated P. quinquefolius L. The findings showed that the fertility of the continuous cropping soil was lower. However, the soil water content was higher and the pH value was lower in the continuous cropping soil, and the urease, phosphatase and sucrase activities were lower than those in the uncultivated soil (Li et al. 2021). The assessment of soil nutrients during the continuous cultivation of Pinellia ternata (Thunb.) Ten. ex Breitenb. showed that the the content of soil organic matter was higher than that of the non-continuous treatment (Zhao et al. 2021). Meanwhile, the same results were found in tobacco (Chen et al. 2023a, b, c) and C. chinensis Franch (Song et al. 2018), the mechanisms remain unclear, and needs further exploration.

Continuous cropping changes the microbial population in the soil, thereby changing the nature of the soil and indirectly affecting the growth and development of plants. Wang et al. analyzed Medicago sativa L. soils of different ages. The results showed that the soil microbial community shifted from fungi to bacteria. The number of beneficial microorganisms was reduced, which led to a gradual increase in the frequency of Medicago sativa L. root rot (Wang et al. 2021c). Barriers to continuous cropping were also identified for Dioscorea polystachya Turczaninow, as an important medicinal and edible plant. Comparative analysis of the inter-root soil of D. polystachya Turczaninow cultivated in the same habitat for 1, 5, 10 and 20 years showed that the relative abundance of beneficial bacteria such as Proteobacteria and Actinobacteria decreased (Yao et al. 2023). Meanwhile, the relative abundance of Gemmatimonadetes and Acidobacteria decreased with increasing cropping duration, and an increase in the frequency of root rot alfalfa also occurred. The relative abundance of harmful bacteria, such as Gemmatimonadetes and Acidobacteria, also increased (Wu et al. 2016a). Bacterial abundance analysis of the soil using qPCR amplification under the long-term cultivation of black pepper showed that the abundance of soil bacteria decreased with an increase in the duration of continuous cultivation (Wu et al. 2015a). Inter-root microbial analyses of continuous cropping of P. ternata (Thunb.) Ten. (Zhao et al. 2021) and Codonopsis pilosula (Franch.) (Zhang et al. 2021) yielded conclusions consistent with these results. The relative abundance of pathogenic in soil increased, while the content of beneficial bacteria decreased. This suggests that the continuous cropping of medicinal plants has a negative feedback effect on beneficial microorganisms in the soil.

Continuous planting of medicinal plants will change soil physical and chemical properties and soil enzyme activities, affect microbial population and diversity, and thus affect the soil microbial structure of medicinal plants. It also inhibits plant growth and development.

Feedback effects of continuous cropping on medicinal plants growth

CCO not only changes the physical and chemical properties of soil and microbial population, but also affects the growth and development of medicinal plants, and changes their yield and quality. As a bulk medicinal material in China, C. pilosula (Franch.) is faced with problems such as CCO in the production process. By comparing its chlorophyll content, the results showed that the chlorophyll a and chlorophyll b contents of continuous cropping C. pilosula (Franch.) were significantly lower than those of non-continuous cropping treatments. There were also differences in superoxide dismutase (SOD) and malondialdehyde (MDA) content between the two treatments (Jiang et al. 2023). The photosynthetic characteristics and osmotic adjustment substances of continuous cropping Angelica sinensis were compared with those of normal cropping Angelica sinensis. The results showed that continuous cropping led to the decrease of chlorophyll content and photosynthesis in leaves, and also led to the decrease of SOD, POD and CAT activities (Zhang et al. 2010). Yan et al. found that Pogostemon cablin (Blanco) Benth were subjected to continuous cropping stress, which resulted in browning of the roots, reduced meristematic branching, and decreased root vigor. In turn, it will lead to the decrease of quality and yield of P. cablin (Blanco) Benth. CCO also led to the activation of MAPK and calcium ion signaling pathways in response to the soil microenvironment (Yan et al. 2022).

Impacts of chemosensory autotoxicity on the production of medicinal plants

Most medicinal plants under continuous cropping secrete self-toxic substances through chemosensitization. This affects their absorption and use of water and nutrients. Butylhydroxytoluene is a toxic substance secreted by P. ternata (Thunb.) Breit, leading to photosynthesis, growth and yield quality decline. (Zhang et al. 2023a). Wang et al. investigated the barriers to continuous cropping of Atractylodes macrocephala Koidz. and analyzed the rhizosphere soil of A. macrocephala Koidz. planted for 3 years in a row. The inter-root soil showed the highest content of dibutyl phthalate and it was found that 2,4-di-tert-butylphenol had an inhibitory effect on the germination of A. macrocephala Koidz. seeds (Wang et al. 2023). Similarly, from 1 to 3 consecutive planting years, Panax notoginseng seedling emergence and survival rates were significantly reduced. Root secretion and inter-root soil extracts showed significant autotoxicity on seedling emergence and growth (Yang et al. 2015). In a follow-up study, Zhao et al. tested the continuous cropping soil of P. notoginseng and found that phenolic acids, such as butyric acid and ferulic acid, were autotoxic to P. notoginseng (Zhao et al. 2018). Similarly, lilies can lead to phthalic acid accumulation during continuous cropping. Both the root secretions and plant extracts of Tribulus terrestris alfalfa can negatively affect emergent growth. Similarly Lilium brownii var. viridulum Baker can lead to phthalic acid accumulation during continuous cropping, and both Medicago truncatula Gaertn. clover root secretions and plant extracts can negatively affect emergent growth (Wu et al. 2015b; Wang et al. 2022b).

These conclusions confirm that most medicinal plants are affected by CCO, which affect their growth and development. This not only affects plant growth and their soil environment, but also inhibits root and seed growth through chemosensitization and autotoxicity. Therefore, medicinal plants should be cultivated in ecologically suitable areas to avoid CCO. Medicinal herb growers change the negative effects of CCO on medicinal plants through crop rotation and intercropping. For example, crop rotation between Panax ginseng C. A. Meyer and Chelidonium majus L. can significantly alleviate ginseng CCO (Zhang et al. 2022b). Meanwhile, intercropping legumes with yam is beneficial for improving the survival rate of D. polystachya Turczaninow (Zhang et al. 2018).

Effects of germplasm resources on development of medicinal plants use

Germplasm resources are the basis of medicinal plants production and an important link to ensure the expansion of medicinal plants. High-quality germplasm resources are the primary conditions for the production of high-quality medicinal plants and an important value index for their stable yield and quality (Li et al. 2017; Morris and Ming 2018). However, there are many problems with the current medicinal plant germplasm resources, such as seed adulteration. Papaver somniferum L. seeds are morphologically similar to Sesamum indicum L. and Amaranthus retroflexus L. seeds. Therefore, they are often used as poppy seeds, and black pepper and papaya seeds are also easily confused in the market. Celosia argentea seeds are often replaced by Celosia cristata seeds and Amaranthus tricolor seeds, owing to their high level of efficacy and high market demand (Avula et al. 2023; Vadivel et al. 2018; Sun et al. 2022b). There are also confusion regarding the variety of medicinal plants used, such as Dendrobium nobile Lindl., which has many varieties and the merchants are inferior, which brings difficulties to the quality classification and identification of D. nobile Lindl. and other medicinal plants (Li et al. 2022; Zhu et al. 2018). There are also medicinal plants that are passed off as genuine. Panax japonicus has stringent origin requirements, which means that it is often marketed as Panax stipuleanatus. Herba Solani Lyrati (Solanum lyratum Thunb.) is morphologically highly similar to Herba Aristolochiae mollissimae (A. mollissima Hance), and they are easily confused with each other. S. lyratum is non-toxic, but A. mollissima contains aristolochic acid I, which is a toxic substance. If they are confused with each other, it can lead to undesirable effects of A. mollissima (Qiu et al. 2023; Liang et al. 2006). In recent years, the authenticity of medicinal plant seeds and their germplasm has been recognized through microscopic, trait, and molecular identification using DNA barcoding technology and multiomics. However, owing to the wide variety of medicinal plants and environmental changes, different genera or species of medicinal plants have been derived from the basal plants. Atractylodes lancea and Atractylodes koreana are medicinal plants of the genus Atractylodes, family Asteraceae. However, their medicinal constituents are quite different, with the content of atractylodes in A. lancea being substantially higher than that in A. koreana. The content of atractylon in A. lancea is also substantially higher than that in A. koreana, while the atractydin content shows the opposite trend (Liu et al. 2016). In response to this situation, the fourth national census of medicinal plants resources was conducted in China. The survey was conducted in 34 provinces using visiting surveys and techniques such as image recognition, and three genera and 196 species of medicinal plants were discovered. These initiatives have laid the foundation for the identification and application of medicinal plants and promoted the development of medicinal plants.

Effects of field management on the development of medicinal plants

Field management refers to management measures such as tillage, weeding, fertilization, and pest control for medicinal plants during the period from sowing or transplanting to harvest. This helps to avoid the impact of adverse factors on the normal growth and development of medicinal plants. Field management is a key step in the accumulation of medicinal plant components.

Knowledge of the life histories of medicinal plants facilitates their cultivation and field management. Sowing is important for the germination of medicinal plant seeds. Usually, the seeds of medicinal plants have dormant characteristics, such as Astragalus membranaceus, Xanthium sibiricum, and Sophora flavescens (Liu et al. 2023). Therefore, medicinal plant seeds should be pre-treated before sowing. Reutealis trisperma (Blanco) Airy Shaw seeds and Robinia pseudoacacia L. seeds have been mechanically polished to break seed dormancy and promote germination (Utami et al. 2021; Bouteiller et al. 2017). Mulch depth also has a certain effect on seedling emergence rate and seedling emergence time. For Calobota sericea (Fabaceae), at sowing depths of 1 or 5 cm, the seedling emergence rates were significantly lower than those at depths of 2, 3, and 4 cm (Müller et al. 2019). Gibberellic Acid (GA3) treatment can significantly increase the Tulipa gesneriana L. seed germination rate, and mulch thickness > 3 cm leads to a decrease in the number of seedlings (Zhang et al. 2020). Seed failure to germinate will lead to reduced plant yields, whereas replanting will lead to a loss of manual effort and economy.

Different planting and mulching practices also affect the growth and water use of medicinal plants (Rafi and Kazemi 2020). Cheshmi et al. studied different planting methods for Beta vulgaris L., the results showed that the root yield, sugar content, and water use efficiency of transplanted Beta vulgaris L. were higher than those of direct sowing (Cheshmi et al. 2023). Different densities of transplanting and shading treatments were performed on Anoectochilus roxburghii (wall). Lindl. The effect of the planting density of 3 × 3 cm test group was the most effective, and the biomass of Anoectochilus roxburghii was the best under 70% shade treatment. Panax quinquefolium planting density also influenced its biomass and ginsenoside effects. The accumulation of P. notoginseng (Burkill) biomass and ginsenoside was higher at the medium density of 15 × 15 cm (Shao et al. 2014; Liu et al. 2021b). Excessive planting density can lead to plant dwarfing, stem thinning, and leaf thinning in medicinal plants, and the microscopic changes in the leaves are mainly reflected in the reduction in stomatal diameter and density. From an economic point of view, moderately dense planting can effectively improve the efficiency of plant use of environmental resources and yield (González et al. 2022; Wan et al. 2023). However, the applicability of this theory to perennial medicinal plants remains to be explored.

Medicinal plants are usually weeded manually. However, some herbal growers suppress weed competition on medicinal plants by applying herbicides. Four herbicides, glyphosate, fluazifop, sethoxydim, and propyzamide, were applied to rhubarb, and compared to manual weeding. The results showed that although the herbicides provided short-term weed control, Rheum palmatum L. yields were lower than those of the manual weeding treatments. Bell pepper (Capsicum annuum) full-season manual weeding increased yields by 4–18% compared to napropamide application. There is also a risk of herbicide residues in medicinal plants following multiple herbicide applications (Richard 1989; Lanini and Strange 1994).

Nutrient management is important for the growth and quality of medicinal plants. It has been shown that fertilizers can significantly increase the biomass, volatile oil production, and other medicinal components of Vitex negundo Linn. (Peng and Ng 2022). A lack of nitrogen leads to slow nutrient growth and the poor development of nutrient-rich organs in medicinal plants. Nitrogen fertilizer can effectively increase the use of nitrogen in soil by medicinal plants, and the protein content in the plant, thereby improving medicinal plant quality (Ge et al. 2021). However, the application of nitrogen can also lead to negative feedback effects in some medicinal plants. P. notoginseng is sensitive to nitrogen, and the biomass of the underground part of P. notoginseng shows a negative correlation with nitrogen. Meanwhile, the biomass of the aboveground part shows a positive correlation with nitrogen. This also leads to a reduction in medicinal components, such as P. ginseng saponins, thus reducing its medicinal qualities (Cun et al. 2023). Nitrogen also regulates the epigenetic inheritance of medicinal plants from a molecular perspective, including DNA methylation, protein modification, and other processes (Zhang et al. 2023b). An appropriate amount of phosphorus fertilizer is beneficial for improving the yield of medicinal plants. The weak mobility of phosphorus in the soil makes it easily fixed by the soil, thus leading to insufficient phosphorus uptake by medicinal plants (Bindraban et al. 2020). Low phosphorus treatments increased the biomass of the aboveground parts of the plant and the content of saikosaponins, but the content of saikosaponins in the roots was reduced. High phosphorus treatments reduced the yield and quality of Bupleurum. (Sun et al. 2022a). Potassium improves stress tolerance in medicinal plants and plays an indispensable role in reproductive growth, metabolism, and photosynthesis (Sustr et al. 2019). Medicinal plants can sense K+ changes, mediate K+ ion channels, and transport proteins to regulate intracellular K+ homeostasis in response to stressful environments by producing chemical and physical signals (Wang and Weihua 2017). Potassium increased the biomass and photosynthesis of Ephedra sinica Stapf. on a macroscopic level, and its PAL activity and ephedrine and pseudoephedrine content on a microscopic level (Liu et al. 2021a). However, the demand for medicinal plants is increasing, and organic fertilizers, microbial fertilizers, green manure, and fungicides are gradually replacing traditional chemical fertilizers. Bio-organic fertilizers can significantly improve the biomass and physiological properties of medicinal plants such as Astragalus and “Qi-Nan” agarwood (Liang et al. 2021; Huang et al. 2023). Meanwhile, organic fertilizers or fungicides also have some mitigating effects on the CCO. Organic fertilizers and fungicides reduce the negative effects of CCO by changing the soil physicochemical properties, root secretions, and microbial species (Chen et al. 2022). Green manure usually refers to the use of plant residues or the direct mulching of plants. Using Nepenthes mirabilis (Lour.) Druce as green manure can significantly increase the volatile oil and muscimol contents of Thymus mongolicus (Ronniger) Ronniger (da Alan et al. 2022). Disease control is the most important aspect of field management, and most medicinal plants use their roots for medicinal purposes. Therefore, root diseases are regarded as potential threats. In recent years, with the deep exploration of microorganisms, the inoculation of arbuscular mycorrhizal fungi (AMF), phosphate-solubilizing bacteria, and Pseudomonas fluorescens has been shown to promote nutrient growth and secondary metabolite accumulation in medicinal plants, and increase the antagonistic effect of medicinal plants against diseases. AMF can significantly reduce the wilt disease of Salvia miltiorrhiza Bunge caused by Fusarium oxysporum, and P. fluorescens significantly reduces the root rot disease of okra caused by Fusarium solani. This, in turn, affects medicinal plant quality and yield (Pu et al. 2022; Najaf et al. 2023).

Effects of primary processing on medicinal plant quality

Harvesting and processing of medicinal plants are also important factors affecting their development and have the greatest impact on their medicinal quality. Different harvesting methods can lead to variable quality in medicinal plants (Tanko et al. 2005). The quality of F. cirrhosa D. Don varied at different reproductive stages was different when it was harvested at flower bud, flowering, late flowering, young fruit, and wilting stages. The results showed that the quality of F. cirrhosa D. Don was the highest in the wilting stage, and the total alkaloid content was the highest in the late flowering stage. The harvesting period of F. cirrhosa D. Don was finalized by detailed evaluation (Ma et al. 2021). The harvesting period had a significant effect on the essential oil content of Origanum vulgare (L.), and pre-flowering harvesting resulted in an increase in the volatile oil percentage (Ali and Mehdi 2018). Hussein et al. Have harvested four aromatic grass species that are widely distributed worldwide at different periods and found that the harvesting period had a significant effect on the volatile oil content of the four species of parsley, dill, coriander, and mint. Their volatile oil content was highest 9, 19, 3, and 6 weeks after sowing (Hussein et al. 2020). The effects of different harvest periods on the total nutrients of Herbaceous Peony Pall were similar, and the contents of total flavonoids and vitamin C reached the peak at the full-bloom stage. Meanwhile, the total phenol content was highest at the bud stage (Li et al. 2020). Therefore, it is very important to select the appropriate harvest period for the quality of medicinal plants.

Different processing methods can affect the production of medicinal plants. There were differences in the volatile oil content of Foeniculum vulgare mills owing to the use of solvent-free microwave extraction or microwave-assisted hydrodistillation. Supercritical CO2 extraction techniques substantially increases the yield of volatile oils compared to the conventional hydrodistillation method, supporting the development of green ecological technologies (Dragan et al. 2023). Tao et al. subjected Rhizoma chuanxiong rhizomes to different conditions, such as stir-frying and steaming, and found that steaming was the most effective concoction method, with higher contents of ferulic acid, senkyunolide I, senkyunolide H, senkyunolide A, Z-ligustilide, and levistolide A (Tao et al. 2016). Common methods for processing medicinal plants include scavenging (washing), slicing, concocting (steaming, boiling, or blanching), and drying (Chen et al. 2023a). Processing can also reduce pesticide residues in medicinal plants. For example, Hairong detected pesticide residues of tebuconazole, prochloraz, and abamectin in Rehmannia glutinosa Libosch using high-performance liquid chromatography (HPLC) after washing, steam drying, carbonization, and boiling, and pesticide residues in Rehmannia were significantly reduced by these processes (He et al. 2020). Different drying methods also have certain effects on the quality and value of Glycyrrhiza uralensis Fisch. The vacuum freeze-drying method is beneficial for the medicinal components glycyrrhetinic acid and glycyrrhizin, and is phenotypically superior to hot-air drying and co-drying methods (Zhu et al. 2023). Therefore, choosing the appropriate processing method at the appropriate harvesting stage without losing medicinal components is an effective way to ensure high-quality products of medicinal plants.

Impacts of storage methods on medicinal plants

Storage method is an important part of the value chain of medicinal plants, and a suitable storage environment is particularly important for the medicinal components, quality, and seeds of medicinal plants. The environment of high temperature, high humidity and the internal components of medicinal plants create a good environment for the growth of fungi and other microorganisms. This in turn, leads to the production of mycotoxins and other harmful substances, not only causing economic losses, but also causing toxic effects on the human body. Aflatoxins, ochratoxins, zearalenones, and other substances severely affect the quality and health of medicinal plants (Zhang et al. 2022c). Mycotoxins in medicinal plants in South Africa were detected by ultra-high pressure liquid chromatography-tandem mass spectrometry. It was found that mycotoxin contamination was widespread. (Ndoro et al. 2022). A total of 729 samples of 19 species of medicinal plants from South Korea were analyzed. The results showed that aflatoxins existed in 124 of these samples (Lee et al. 2014). In summary, this indicates that microbial contamination should be avoided during storage of medicinal plants. Appropriate methods should be taken in time to inhibit the microbial growth of Aspergillus flavus, Aspergillus ochraceus, and other microorganisms. Storage time and temperature also have an effect on the potency of the constituents. The presence of moisture in Morinda officinalis at a storage temperature of 25 °C can lead to the hydrolysis of oligosaccharides. Meanwhile, at − 7 °C, the sugar level is more stable. Therefore, Morinda officinalis should be stored at low temperatures to ensure that its internal sugar content remains unchanged (Sun et al. 2011). Seed vigor was also significantly affected by storage temperature. The germination potential and germination rate of rhubarb seeds stored at − 18, − 4, and 4 °C were determined. The results indicated that the germination potential and cell permeability of seeds stored at − 4 °C were significantly higher than that of seeds stored at 4 °C (Hou et al. 2022). These findings indicate that storage environment is particularly important for medicinal plants.

Challenges in the development of medicinal plants

With the continuous progress of medical treatment, the demand for medicinal plants has been increasing. This has led to the excavation of wild resources, the extreme reduction in the number of wild medicinal plants, and the imbalance between demand and supply. Therefore, to compensate for the balance between the supply and demand for medicinal plants, farmers have begun to cultivate medicinal plants. However, problems such as confusion regarding germplasm resources and improper field management during cultivation have resulted in lower levels of medicinal components under artificial cultivation conditions compared to those found in the wild.

The Korean Pharmacopoeia specifies that the pharmacodynamic constituents of A. sinensis are nodakenin, decursin, and decursinolangelate, with a total of at least 6.00 g/100 g. The yield of cultivated A. sinensis roots is higher than that of wild A. sinensis. However, the content of pharmacodynamic constituents is considerably lower than that in the wild environment, and lower than that specified in the Pharmacopoeia (Park et al. 2020). Yuan investigated the differences in the main pharmacodynamic constituents of D. officinale under three conditions, that is, wild-like cultivation, greenhouse cultivation, and wild cultivation. It was found that the total polysaccharide alkaloids and total flavonoid content of D. officinale cultivated in the wild were higher than those of the other two cultivation methods (Yuan et al. 2020). The same conclusion has been reached for wild and cultivated licorice. Here, the contents of flavonoid compounds and secondary metabolites, such as isoglycyrrhizin, were significantly higher in wild licorice than in cultivated Glycyrrhiza uralensis (Wang et al. 2021a). Therefore, to ensure the safety, efficacy, and quality of medicinal plants, the European Union, the WHO, and the United States have successively formulated relevant specifications, the Good Agricultural and Collection Practices (GACP). In December 1998, China drafted the Good Agricultural Practice (GAP) certification for Chinese herbal medicines. The Chinese Pharmacopoeia, Japanese Pharmacopoeia, and Korean Pharmacopoeia have summarized different types of medicinal plants to develop detailed quality standards (Yang et al. 2022a). However, given that the certification of medicinal plants varies from country to country, it is difficult to avoid these differences.

There is a large demand for medicinal plants in China, and since its accession to the World Trade Organization, the export of medicinal plants, number of participating economies, and trade exchanges have shown an upward trend in China (Xiang et al. 2022). However, the trade barriers and technology of each country can have a severe impact on the export of medicinal plants, especially the green barriers to China’s exports of medicinal plants of the Food and Drug Administration: the weak environmental protection awareness of Chinese enterprises and the excessive application of fertilizers and pesticides, resulting in the substandard quality being rejected. Nevertheless, due to technical barriers, an increase in production costs and supply imbalance can limit the export of medicinal plants (Yang et al. 2021). Therefore, to realize the development of the global trade of medicinal plants, researchers have been continuously integrating international standards and developing a quality completion system for seedlings, herbs, and proprietary Chinese medicines. Examples include the ISO/TC249 platform (Huang et al. 2020), biophotonic methods (Cao et al. 2023), optical microscopy, and electron microscopy (Ahmed et al. 2020) for medicinal plants quantification and certification. In recent years, the European Union’s regulatory framework has opened up to multiple combinations of herbal medicines. However, scientific language is still needed to describe traditional processing and the production of multi-flavor herbal products (Qu et al. 2022).

The intellectual property protection rights and protection rights of medicinal plants in China including those for medicinal plants, are also relatively weak and there are few international patent achievements (Lin et al. 2018). The theory of traditional Chinese medicine takes qi, blood, yin, organs and meridians as the entry point. However, Western medicine is based on the structure or anatomy of the human body. This in turn, contributes to the lack of acceptance of Chinese medicine theories in the West and is also a challenge for the internationalization of medicinal plants (Tang et al. 2018; Sun et al. 2013).

Discussion and conclusion

This paper emphasized the effects of these factors on medicinal plants from the aspects of continuous cropping obstacles, climate change, field management methods, processing and harvesting, and related policies. Currently 4000–10,000 species of medicinal plants are globally endangered due to overexploitation, reduced number of medicinal plants, loss of genetic diversity and habitat degradation (Canter et al. 2005). Therefore, medicinal plant resources need to be moderately excavated and conservation measures should be taken. Giday et al. suggested that medicinal plants should be protected by in situ conservation or home domestication and advocated for the establishment of more markets in source-rich areas, conducive to the sustainable development of medicinal plants (Giday et al. 2016; Wang et al. 2020). To address CCO, soil improvement and planting systems should be combined to coordinate the relationships between plants, microorganisms, and soil (Zeeshan et al. 2023). Meanwhile, given the diversity and complexity of medicinal plants, the combination of breeding and biotechnology can promote their development (Niazian. 2019). Excellent germplasm resources have been screened through selective breeding, hybrid breeding, mutation breeding, plant tissue culture, and polyploid mutation breeding. The researchers have also focused on exploiting the mutagenic resistance of medicinal plants. Glycyrrhiza glabra L. has anti-gram-positive bacterial properties and an inhibitory effect on mutations caused by oxidation (Faruk et al. 2016). Akram et al. found that more than a dozen species of medicinal plants have anti-mutagenic potential. This can be used as a potential medicine for anticancer, antimicrobial, and antioxidant effects (Akram et al. 2020). Currently, multi-omics studies using transcriptomics and metabolomics of medicinal plants provide theoretical support for the accumulation of medicinal components in medicinal plants (Yang et al. 2023). However, the domestication of wild medicinal plant resources has been constrained by the weakening and destruction of common property rights, such as quality, safety, and traceability, thus limiting the global value chain of medicinal plants. Therefore, medicinal farmers, buyers, processors, and marketers should be integrated to promote sustainable development of medicinal plant value chains around feedback loops, complementarities, and synergies of indigenous property rights, collective action, knowledge, power relations and agency (Volenzo and Odiyo 2020). Some farms in India have cultivated medicinal plants, such as Aloe barbadensis and Curcuma longa L., as alternatives to local traditional crops (rice and wheat) and compared their economic potential. The economic value of medicinal plants is substantially higher than that of rice and wheat (Singh et al. 2023). The development of medicinal plant value chains can not only lead to better healthcare, but also reduce poverty and increase human well-being (Rios et al. 2017). The popularization of satellite and drone technology in agricultural production is important for the sustainable development, resource utilization, and ecological conservation of medicinal plants. UAV multispectral sensors can be applied for diagnose nutrient element deficiencies and sensitivity assessment of medicinal plants (Li et al. 2023). The combination of 3S technology and stratified field research can be used to investigate the resources of wild medicinal plants. Low-altitude UAV remote sensing technology can be applied to the investigation of cultivated medicinal plant resources (Guo et al. 2021). Hyperspectral remote sensing technology has advantages in the identification of the biomass, biochemical substances, and qualities of plants (Zhang et al. 2013). Similarly, the use of remote sensing and spatial modeling in conjunction with each other plays an important role in the distribution of wild medicinal plant resources and in analyzing the climatic factors affecting their medicinal components (Li et al. 2015).

Medicinal plants not only play a role in clinical treatment but also are particularly important in beverages and diets (Ivanka et al. 2022). Therefore, safety is essential, and improving pharmacovigilance is a prerequisite to safeguard the use of medicines. In this context, the development of medicinal plants should be strengthened through the following measures: (1) improving the understanding of medicinal materials farmers and processing plants on the quality and quality assurance of medicinal materials; (2) further exploring the use value of medicinal plants; (3) promoting the internationalization of medicinal plants and strengthening international exchanges; (4) enhancing the progress of medicinal plants breeding to improve the ability of medicinal plants to cope with adverse environments; (5) improving the potential of joint analysis of various groups and further in-depth research can provide a theoretical basis for analyzing the breeding of medicinal plants and improving their efficacy and (6) conducting value chain analysis of medicinal plants to facilitate the distribution of benefits at different levels and promote the sustainable development of medicinal plant use.