1 Introduction

Fritillaria thunbergii Miq., the source plant of Fritillariae Thunbergii Bulbus (Zhebeimu), is a long-used traditional Chinese medicinal species whose dried bulbs are valued for antitussive, expectorant, anti-inflammatory, anti-ulcer, analgesic, and other pharmacological activities (Nile et al., 2021). It is one of the officially recognized medicinal Fritillaria sources in the Chinese Pharmacopoeia and is widely cultivated in southeastern and east-central China, especially in Zhejiang, Jiangsu, Anhui, Hunan, and major authentic-production areas such as Ningbo and Pan’an (He et al, 2021; Liu et al., 2025). Because its bulbs contain diverse bioactive constituents, particularly steroidal alkaloids such as peimine and peiminine, F. thunbergii has become one of the representative medicinal bulbs within the Beimu market and an important component of the “Zhejiang Eight Flavors” geo-authentic medicinal industry (Huang et al., 2024). At the same time, the broader Fritillaria market has substantial and persistent demand, and artificial cultivation has been recognized as a necessary strategy to protect wild resources and relieve the contradiction between supply and demand in medicinal Fritillaria industries. Although F. thunbergii itself has a long history of commercial bulb reproduction in China, with bulb propagation technology adopted centuries ago, the contemporary industry still faces unstable quality and yield, inefficient cultivation links, and market pressures that increasingly demand standardized, high-quality propagation materials for sustainable large-scale production (Qu et al., 2022).

The quality of propagation bulbs directly influences field establishment, vegetative growth, resistance performance, final yield, and the formation of medicinal quality in F. thunbergii. In medicinal production, excessive pursuit of biomass or yield can reduce the accumulation of active ingredients and lower the proportion of bulbs meeting commercial standards, showing that productive performance and medicinal quality must be coordinated rather than treated separately (Liu et al., 2025). Recent cultivation studies further show that bulb yield and alkaloid quality are highly sensitive to agronomic conditions: organic fertilizer increased peimine and peiminine contents to 0.0603% and 0.0502%, respectively, while producing a yield of 2.70 kg/m², and potassium supply above 40 kg K₂O/hm² allowed bulb quality to meet Pharmacopoeia standards while 108.4~128.0 kg K₂O/hm² optimized yield. Shading likewise increased active ingredient accumulation by about 11.7% to 20.71%, but reduced bulb biomass by about 11.3% to 17.24%, whereas combined shading and potassium application partly alleviated the biomass penalty while improving medicinal constituent accumulation and pharmacological activity. These findings indicate that bulb quality is not merely a matter of size; it reflects a complex integration of physiological vigor, nutrient status, environmental adaptation, and secondary metabolite biosynthesis, including key pathways linked to ABA signaling and steroidal alkaloid accumulation. Consistent with this, variety differences also translate into propagation and production differences: the cultivar “Zhebei 3” showed a bulb proliferation rate of 261.2%, a propagation coefficient of about 1:2.6, higher yield, higher peimine plus peiminine content, and better resistance to bulb stem soft rot than controls (Jiang et al., 2019).

For F. thunbergii, securing high-quality propagation materials is especially important because conventional reproduction is inherently slow and faces biological and sanitary constraints. Across Fritillaria, bulb reproduction is the main domestication method and usually requires about 100 days to 3 years, whereas sexual reproduction by seed often takes more than five years, making rapid multiplication of elite materials difficult. In bulbous plants, natural propagation rates are generally low, only a few daughter bulbs are produced annually, and using limited mother-bulb material can increase the risk of transmitting viral and fungal infections to progeny bulbs (Marković et al., 2021). This has driven the development of rapid propagation and micropropagation technologies in Fritillaria, which are important not only for commercial multiplication but also for germplasm conservation and the production of healthy starting materials. For F. thunbergii specifically, high-frequency in vitro bulblet regeneration has already been achieved from bulb-scale explants, with an optimum of 13.7 bulblets per scale section on MS medium containing 1.62 μmol/L NAA and 4.65 mol/L KN, leaf and root formation within 12 weeks, and 100% sprouting after transplanting when bulblets exceeded 10 mm following 5 weeks of cold treatment. Established tissue-culture systems for F. thunbergii and other medicinal Fritillaria species show that hormone composition, light, temperature, and dormancy release are key technical nodes, while regenerated bulbs may even accumulate more alkaloids than wild bulbs, though consistency in morphology and phytochemical profile remains a barrier to marketization (Qu et al., 2022).

Against this background, research on bulb propagation techniques of F. thunbergii should aim to integrate germplasm selection, healthy seed-bulb production, rapid multiplication, dormancy regulation, and quality-oriented cultivation into a scalable technical system for industrial application. Such research is significant because it can shorten propagation cycles, improve the multiplication coefficient of elite lines, stabilize field performance, and coordinate yield with medicinal quality, thereby addressing current bottlenecks in large-scale cultivation. It can also support sexual propagation and early seedling-bulb utilization, since seedling bulbs have been shown to reach the total alkaloid standard required by the Chinese Pharmacopoeia, providing a basis for expanding propagation pathways beyond traditional bulb splitting alone. In parallel, modern quality-evaluation tools, including HPLC fingerprinting and multicomponent quantification as well as hyperspectral imaging with deep learning, provide practical means for discriminating varieties, monitoring consistency, and strengthening standardized quality control of propagation materials and commercial bulbs. Therefore, systematic study of bulb propagation techniques and their large-scale production application is not only a technical need for improving the productivity and quality stability of F. thunbergii, but also a strategic requirement for safeguarding geo-authentic medicinal resources, enhancing industrial competitiveness, and promoting the sustainable development of the F. thunbergii industry.

2 Biological Characteristics and Foundation of Bulb Propagation in Fritillaria thunbergii

2.1 Growth and development characteristics and bulb formation patterns of Fritillaria thunbergii

Fritillaria thunbergii is a perennial bulbous medicinal plant whose commercial organ is the dried bulb, and artificial cultivation has long relied on the biology of bulb growth and renewal rather than on rapid seed-based turnover (He et al., 2021; Qu et al., 2022). In cultivated production, its growth cycle is distinctly seasonal: one field study reported planting in mid-September with sprouting the following season, while another experiment recorded October planting and emergence in February, indicating a clear autumn planting-winter dormancy-spring emergence rhythm (Liu et al., 2025). Variety traits modify this rhythm, as the cultivar “Zhebei 3” emerged early, senesced later, and showed an average growth period of about 100 days, longer than the comparison cultivars (Jiang et al., 2019). Bulb enlargement is concentrated in a relatively short developmental window, with rapid filling beginning 32 days after sprouting and full bulb growth requiring about 72 days, which helps explain why cultivation management during the expansion stage has disproportionate effects on final bulb size and propagation value.

Bulb formation in F. thunbergii follows the general geophyte pattern in which daughter bulbs arise from the mother bulb and then pass through dormancy before sprouting in the next cycle (Marković et al., 2021). Temperature is central to this pattern: high temperatures induce dormancy, whereas winter chilling breaks dormancy and promotes spring sprouting, and fritillary bulbs regenerated in vitro likewise fail to resume normal growth unless they receive low-temperature treatment. Evidence from F. thunbergii tissue culture matches this developmental requirement, because regenerated bulblets were cold-treated at 5℃ for 5 weeks, and bulblets larger than 10 mm then achieved 100% sprouting after transplantation. At the molecular level, bulb development also appears to be linked to hormonal regulation, as ABA-related signaling was associated with bulb yield and the gene FtGGPS was implicated in coordinating GA and ABA levels during bulb development, providing a mechanistic basis for differences in bulb expansion and propagation coefficient among cultivars (Huang et al., 2024; Xu et al., 2026).

2.2 Propagation methods and bulb development processes of Fritillaria thunbergii

The propagation of F. thunbergii mainly includes vegetative bulb reproduction, seed reproduction, and in vitro rapid propagation, with bulb reproduction historically serving as the principal domestication method. Across Fritillaria, bulb reproduction generally requires about 100 days to 3 years, whereas seed reproduction usually takes more than five years, which is why bulbs are commonly used as planting material in production systems seeking faster turnover (Qu et al., 2022). Even so, seed-based pathways still matter for breeding and propagation diversification, and an early study showed that total alkaloid content in F. thunbergii seedling bulbs already met the Pharmacopoeia standard, supporting the practical value of sexual propagation for future production. Conventional vegetative propagation remains biologically constrained because only a few daughter bulbs can be produced from each mother bulb each year, and repeated use of mother bulbs can also transmit viral and fungal infections to progeny bulbs (Marković et al., 2021).

For these reasons, tissue culture has become a key supplementary route for large-scale propagation of F. thunbergii (Qu et al., 2022). In vitro morphogenesis in fritillaries can be induced from bulbs, bulb scales, inflorescence parts, and embryos, and whole plants can be regenerated through bulblet formation or somatic embryogenesis. For F. thunbergii specifically, bulb-scale sections cultured on MS medium with 1.62 μM NAA and 4.65 μmol/L KN produced an optimum of 13.7 bulblets per explant, and these bulblets formed leaves and roots within 12 weeks under a 16 h light/8 h dark regime at 25℃. Other culture work found that combinations of 2,4-D and kinetin were more effective than NAA and BA for bulblet induction, that most bulbs formed from axillary buds of nodal explants, and that light culture outperformed dark culture for bulb formation, shoot growth, callusing, and rooting. Taken together, the developmental process of propagated bulbs in F. thunbergii can be summarized as explant induction, bulblet differentiation, root and shoot formation, dormancy establishment, low-temperature dormancy release, and transplant establishment, after which field bulb expansion determines whether the propagated material becomes productive seed bulbs or commercial medicinal bulbs (Marković et al., 2021).

2.3 Main factors affecting bulb quality formation in Fritillaria thunbergii

Bulb quality formation in F. thunbergii depends on the interaction of genotype, cultivation year, nutrient supply, light environment, and rhizosphere ecology, and quality must be understood as both biomass performance and accumulation of steroidal alkaloids such as peimine and peiminine (Nile et al., 2021). Genotypic differences are already evident in elite materials: “Zhebei 3” had a bulb proliferation rate of 261.2%, a propagation coefficient of about 1:2.6, higher yield, higher combined peimine and peiminine content, and better resistance to bulb stem soft rot than controls (Jiang et al., 2019). Cultivation duration also changes bulb output, because yield increased by 88% at two years and 189% at three years relative to one year, although the proportion of bulbs heavier than 5 g declined from 89% at one year to 77% at three years, indicating a trade-off between cumulative yield and size structure. Quality control studies further show that production origin and cultivation environment can shift chemical profiles, since Zhejiang samples clustered together whereas Nantong, Jiangsu material separated from them in HPLC fingerprinting analyses (He et al., 2021).

Nutrient and ecological management have especially strong effects on medicinal quality formation. Fertilization influences both yield and quality, and organic fertilizer gave the best combined performance in one recent study, with peimine and peiminine contents of 0.0603% and 0.0502% and a yield of 2.70 kg/m² (Huang et al., 2024). Potassium is particularly important: bulb quality met Pharmacopoeia standards above 40 kg K₂O/hm², yield rose to a plateau above about 120 kg K₂O/hm², and the optimal K range for yield was 108.4-128.0 kg K₂O/hm². Shading increased active ingredient accumulation by about 11.7~20.71% but reduced bulb biomass by about 11.3~17.24%, whereas combining shading with potassium partly offset the biomass penalty and enhanced steroidal alkaloid accumulation and pharmacological activity (Liu et al., 2025). Soil-centered strategies also matter: compost and manure increased yield and marketable proportion in older fertilizer trials, while recent understory work showed that biochar plus organic fertilizer improved yield, total alkaloids, soil nutrients, beneficial microbes, and overall rhizosphere function (Liu et al., 2026). At the mechanistic level, bulb quality formation appears to involve both plant metabolic regulation and microecological mediation, including ABA signaling, FtFPS-linked steroidal alkaloid biosynthesis, and rhizosphere microbial groups positively associated with medicinal component accumulation.

3 Key Technologies for Bulb Propagation of Fritillaria thunbergii

3.1 Conventional bulb division propagation technology and its application characteristics

Conventional bulb division propagation of Fritillaria thunbergii is based on the natural renewal pattern of mother bulbs producing daughter bulbs, and this has long been the principal domestication and commercial reproduction route for the species (Li et al., 2019). In Fritillaria more broadly, vegetative multiplication through bulb splitting remains standard because seed propagation is slow and of limited practical value for production, with seedlings requiring many years to develop usable bulbs. Evidence from the related medicinal species F. cirrhosa provides a comparative example of in vitro bulblet regeneration (Figure 1) (Chang et al., 2020; Marković et al., 2021; Thakur et al., 2024). The main advantage of this method is that it is simple, field-adapted, and does not require specialized facilities, so it remains suitable for traditional production bases and routine nursery multiplication of locally adapted germplasm (Bhardwaj et al., 2025; Hasnain et al., 2022). Its practical application also depends strongly on varietal traits, because elite cultivars differ in multiplication coefficient, bulb vigor, and disease resistance, as shown by “Zhebei 3,” which had a bulb proliferation rate of 261.2%, a propagation coefficient of about 1:2.6, and better resistance to bulb stem soft rot than the controls.

Figure 1 F. cirrhosa (Adopted from Chang et al., 2020) Image caption: a: In vitro seed germination on MS basal medium supplemented with BA (1.0 mg/L), NAA (0.4 mg/L) after incubation for 20 days (bar=1.8 cm). b: Bulblet and callus formation in 4 month old seedlings growing on 1/2X MS basal medium supplemented with sucrose (2.5%), GPP (0.4%) (bar=1.24 cm); c, d, e: Bulblet regeneration from bulb sections after 2 months of culture (c, bar=0.25 cm); at the end of subculture 2 (6 months) (d, bar=0.9 cm, arrow showing a bulblet); and at the end of subculture 5 (12 months) (e, bar=1.5 cm); f: Callus growth under darkness (bar=1.8 cm) (Adopted from Chang et al., 2020)

The main limitation of conventional division is its inherently low propagation rate, since only a few daughter bulbs are produced from each mother bulb annually, making it difficult to meet the demand for rapid expansion of standardized planting materials (Chang et al., 2020). This method also carries a sanitary risk, because repeated use of mother bulbs can transfer viral and fungal infections to daughter bulbs and gradually reduce population health. In addition, conventional vegetative propagation in bulbous crops is often economically inefficient because development is slow and commercial profitability may require several years (Marković et al., 2021). For that reason, conventional division in F. thunbergii is best understood as a reliable but slow baseline technology, most useful for maintaining elite field materials and supplying initial propagules, while large-scale industrial multiplication increasingly requires combination with scale propagation and tissue culture (Bhardwaj et al., 2025).

3.2 Scale propagation and rapid multiplication technology using bulb scales and bulblets

Scale propagation uses bulb scales or scale sections as explants to induce direct bulblet formation, and it is one of the most important rapid multiplication routes developed for F. thunbergii (Chang et al., 2020). In a classic F. thunbergii study, bulb-scale sections cultured on MS medium produced a high frequency of bulblets, with an optimum of 13.7 bulblets per scale section on medium containing 1.62 μmol/L NAA and 4.65 μmol/L KN (Marković et al., 2023). Light and temperature are key to this process, because a 16 h light/8 h dark regime at 25℃ produced better bulblet formation than continuous darkness (Pasternak and Steinmacher, 2024). Earlier culture-method work in F. thunbergii also showed that solid MS medium with 1.0 mg/L kinetin and 0.3 mg/L NAA outperformed liquid and suspension culture for bulblet formation and propagation rate, while activated charcoal and 1%~2% mannitol further promoted bulbing and subsequent bulblet growth.

The application value of scale propagation lies in its ability to raise multiplication efficiency while using limited source material, and in fritillaries generally bulb scales are among the most effective explants for morphogenesis and rapid regeneration. This route also reduces pressure on whole mother bulbs, and in vitro-derived bulbs or bulb parts can lower contamination and reduce destructive harvesting of source populations (Chang et al., 2020). However, scale propagation remains sensitive to plant growth regulator combinations and explant source, because different auxin-cytokinin balances can shift cultures toward bulblet formation, shoot proliferation, or somatic embryogenesis rather than a single uniform response (Marković et al., 2023). As a result, scale-based rapid multiplication is highly useful for nursery expansion of seed bulbs and for bridging field production with laboratory propagation, but it still requires precise control of medium composition, explant physiological state, and dormancy management before it can be stably translated into year-round industrial production (Marković et al., 2021).

3.3 Tissue culture propagation and rapid expansion technology for high-quality planting materials

Tissue culture propagation provides the most promising route for rapid expansion of high-quality F. thunbergii planting materials because it enables aseptic, season-independent, and large-scale clonal multiplication from small explants (Hamdeni et al., 2022; Thakur et al., 2024). More generally, high-quality planting material for horticultural production should be genetically uniform, physiologically vigorous, and pathogen-free, and tissue culture is valued precisely because it can reduce disease transmission while accelerating multiplication (Bhardwaj et al., 2025). In F. thunbergii, micropropagation systems have been established from bulblet scales, stems, node-buds, and shoot tips, and explant age strongly affects response. Node-bud and young stem tissues can outperform bulb-scale segments, with young tissues below 3 cm shoot length showing stronger regeneration and a maximum multiplication rate of about 20-fold. Organogenic routes are also explant-specific, because many bulbs in culture are formed directly from axillary buds, and favorable kinetin concentrations for bulblet induction vary by source tissue from 1.0 to 5.0 mg/L.

The industrialization of tissue-culture propagation depends not only on multiplication, but also on stable dormancy release, acclimatization, genetic fidelity, and cost control (Hamdeni et al., 2022). In fritillary bulbs, dormancy is a major bottleneck, and low-temperature pretreatment is often essential for sprouting; in F. thunbergii, bulblets chilled at 5℃ for 5 weeks and larger than 10 mm achieved 100% sprouting after transplantation. Broader fritillary evidence shows that short cold treatments can markedly improve sprouting, whereas prolonged chilling may reduce sprouting percentage, underscoring the need for calibrated dormancy-breaking protocols (Marković et al., 2021). For large-scale production of high-quality seed bulbs, current research also emphasizes species-specific protocol optimization rather than uniform historical recipes, along with early monitoring of somaclonal variation and the use of improved systems such as low-cost media strategies, molecular diagnostics, and bioreactor-supported propagation (Pasternak and Steinmacher, 2024).

4 Bulb Quality Evaluation and Standardized Production System of Fritillaria thunbergii

4.1 Evaluation of bulb morphological characteristics and external quality

The external quality evaluation of Fritillaria thunbergii bulbs should begin with macroscopic observation, because raw-material assessment in herbal medicines routinely starts from organoleptic and visual inspection of identity, appearance, and abnormalities (Wang et al., 2023). For Fritillaria bulbs specifically, morphological traits differ significantly among cultivated species, and these differences are useful for source identification and medication safety control. Among measured external traits, the short diameter of the bulb was identified as the most important indicator for distinguishing species, indicating that bulb size and shape should be core descriptors in F. thunbergii grading. Recent work on Fritillariae thunbergii Bulbus further argues that traditional morphological assessment should not be discarded, but integrated with chemical profiling because external traits can correlate with intrinsic quality parameters (Zhang et al., 2026).

In practice, morphological evaluation of F. thunbergii bulbs should include size uniformity, transverse and longitudinal diameter, fullness, surface integrity, color, and freedom from visible rot or blight lesions. This is especially important because bulb diseases can rapidly destroy commercial quality: in Zhejiang fields, blight incidence reached 20~25%, with early browning of the stalk followed by complete bulb rot within days (Xu et al., 2022). External morphology also reflects internal structural differences in storage materials, since Fritillaria starch granules vary in size and shape across species, and F. thunbergii starch granules ranged from 5 to 30 μm, supporting the view that bulb appearance is linked to underlying compositional traits. Because production origin affects quality, morphological assessment should also be interpreted together with provenance information, as Zhejiang and non-Zhejiang materials can differ enough to require origin authentication in market standardization (Zhang et al., 2026).

4.2 Evaluation of nutrient accumulation and physiological indicators of bulbs

The internal quality of F. thunbergii bulbs is determined primarily by the accumulation of alkaloids, carbohydrates, amino acids, nucleosides, and related metabolites, with steroidal alkaloids remaining the most important medicinal components (Nile et al., 2021; Cheng et al., 2023). Quantitative analysis of peimine and peiminine is therefore central to bulb evaluation, and cultivation studies show that these compounds respond strongly to management conditions. Organic fertilizer produced bulbs with peimine and peiminine contents of 0.0603% and 0.0502%, together with a yield of 2.70 kg/m² (Huang et al., 2024). Potassium fertilization increased bulb yield, peimine and peiminine content, and net income by 6.4~23.8%, 2.1~26.6%, and 47.7~205.4%, respectively, and both yield and quality were positively correlated with potassium accumulation in underground parts. These findings show that nutrient accumulation indicators should include not only active alkaloid content, but also mineral accumulation and biomass partitioning to bulbs (Sui et al., 2021).

Physiological evaluation should also recognize that bulb quality is spatially heterogeneous within the bulb and dynamically shaped by ecological regulation. Multi-omics analysis showed that the outer scale layers were enriched in total alkaloids, peimine, and flavonoids by about 1.18-fold, 1.28-fold, and 1.24-fold, whereas the inner layers accumulated more sucrose and starch, at 1.37-fold and 2.18-fold of the outer layers (Wang et al., 2026). Shading increased active ingredient content by about 20.71% but reduced biomass by about 17.24%, while potassium under shading improved both medicinal substance accumulation and pharmacological performance, with the K2S treatment giving the best antitussive, expectorant, and anti-inflammatory effects (Liu et al., 2025). Biocontrol-agent application likewise significantly enhanced plant growth and increased steroidal alkaloids, including peimine and peiminine, while metabolomic profiling identified 48 alkaloids in treated and control bulbs (Cheng et al., 2023). Taken together, nutrient and physiological evaluation of F. thunbergii bulbs should combine targeted alkaloid quantification, carbohydrate and starch assessment, and responsiveness to cultivation conditions that affect biosynthesis pathways such as ABA signaling, oxidative phosphorylation, and alkaloid-related genes (Huang et al., 2024; Liu et al., 2025).

4.3 Establishment of bulb grading standards and quality control systems

A standardized production system for F. thunbergii bulbs should extend from raw-material evaluation to finished-product control, because herbal medicine quality cannot be assured by end-point testing alone. Standardization in herbal medicines is fundamentally the assurance of identification, quality, and purity across the whole life cycle, and current guidance emphasizes pharmacopoeial criteria, WHO-style standardization parameters, and in-process controls rather than isolated appearance checks. For F. thunbergii, a practical bulb grading system should therefore combine external grade descriptors with internal quality markers. Morphological descriptors should include bulb diameter, mass, uniformity, integrity, and disease-free status, while chemical grade descriptors should include peimine, peiminine, and broader alkaloid fingerprints (He et al., 2021; Zhang et al., 2026). The concept of quality markers (Q-markers) is particularly useful here, because it provides a basis for linking raw bulbs, processing stages, and final medicinal efficacy in one traceable system.

The quality control system should also specify the methods used at each stage. Raw bulbs should undergo documental, organoleptic, physicochemical, and microbiological evaluation, supported by macroscopic and microscopic examination, chromatographic analysis, and contaminant testing for heavy metals and other hazards. For chemical authentication and consistency control, HPLC-ELSD fingerprinting with multicomponent quantification has already shown that Zhejiang samples cluster together while some Jiangsu materials separate, indicating that fingerprint analysis can discriminate origin-related quality variation (He et al., 2021). LC-MS combined with chemometrics can further differentiate Zhejiang from non-Zhejiang materials and identify 11 alkaloid markers significantly correlated with external morphology, which supports a more rigorous origin-specific grading framework (Zhang et al., 2026). At the production level, standardized protocols should be implemented under propagation and cultivation, with proper documentation, personnel training, hygiene, SOPs, and traceability from bulb propagation to processing, because only this full-chain approach can stabilize the composition, safety, and clinical consistency of F. thunbergii products (Wang et al., 2023).

5 Large-scale Production Models and Applications of Fritillaria thunbergii Bulbs

5.1 Regionalized bulb propagation production models based on cultivation conditions

Regionalized production models for Fritillaria thunbergii bulbs should be built around the species’ established cultivation belt in southeastern and central-eastern China, especially Zhejiang, Jiangsu, and Anhui, because production origin and local cultivation environment measurably affect both bulb quality and industrial suitability (He, 2021). Zhejiang remains the core region for geo-authentic production, and elite cultivars such as “Zhebei 3” have shown stable characters, higher yield, stronger disease resistance, and suitability for planting in Zhejiang Province, supporting a cultivar-by-region matching strategy rather than a uniform national model (Jiang et al., 2019). Field evidence also shows that cultivation models must be adjusted to local edaphic conditions, because the major coastal production regions are characterized by relatively high soil salinity, while understory systems face poor fertility constraints that require different soil-improvement strategies (Liu et al., 2025; Liu et al., 2026). More broadly, Fritillaria domestication research supports region-specific artificial cultivation, careful survey of growth environments, and integration of bulb and tissue-culture propagation with seed systems where appropriate (Figure 2) (Qu et al., 2022).

Figure 2 Figure 2 Artificial and imitating wild cultivation of F. thunbergii (Adopted from Qu et al., 2022) Image caption: (A): The large-scale artificial cultivation of F. thunbergii in Zhangshui town of Ningbo in Zhejiang Province of China; (B): The imitating wild cultivation of F. thunbergii in Siming Mountain in Zhejiang Province of China; (C): The F. thunbergii Flos; (D): The bulb of F. thunbergii by artificial cultivation, Bar: 1 cm; (E): The bulb of F. thunbergii by the imitating wild cultivation; Bar: 1 cm (Adopted from Qu et al., 2022)

Within these regional models, production conditions should be optimized for the local balance between yield and medicinal quality rather than yield alone. In Pan’an, Zhejiang, organic fertilizer produced the best combined outcome, with peimine and peiminine contents of 0.0603% and 0.0502% and a yield of 2.70 kg/m², indicating that fertilization schemes can be regionally standardized around local soil conditions (Huang et al., 2024). Potassium management is another core regional variable, because field studies across two cultivars showed that potassium fertilization increased bulb yield, bulb quality, and net income, with 120 kg K₂O/hm² emerging as the best overall rate when economic and environmental benefits were considered (Sui et al., 2021). In areas using ecological or understory cultivation, biochar plus organic fertilizer appears especially suitable, because it improved yield, total alkaloids, soil nutrient status, and rhizosphere microbial structure under forest conditions (Liu et al., 2026). In contrast, where light is excessive or medicinal quality is prioritized, regional ecological regulation by shading combined with potassium can increase active ingredients while partly offsetting the biomass penalty of shading alone, which supports differentiated production models for medicinal bulbs versus propagation bulbs (Liu et al., 2025).

5.2 Integration of bulb propagation, storage, and scalable production technologies

Large-scale production depends on linking rapid propagation with reliable storage and transplant establishment. Conventional bulb reproduction remains the main domestication method in Fritillaria, but its multiplication cycle ranges from about 100 days to 3 years, so industrial systems increasingly need to combine field bulb propagation with in vitro multiplication to supply enough healthy seed bulbs (Qu et al., 2022). In F. thunbergii, bulb-scale culture already provides a workable expansion route, producing an optimum of 13.7 bulblets per explant on solid MS medium, with leaf and root formation within 12 weeks. More generally across Fritillaria, bulb scales are among the most effective explants for large-scale morphogenesis, and tissue culture can provide many homogeneous plants year-round from small amounts of starting material (Marković et al., 2023). This propagation module can be paired with regional field nurseries, where elite bulbs are further enlarged under standardized fertilizer and spacing regimes before entering commercial production (Liu et al., 2025).

Storage and post-propagation handling are equally important because dormancy is a major bottleneck in bulb multiplication systems. Bulbs produced in vitro enter dormancy and must undergo controlled low-temperature treatment before uniform sprouting in the next vegetation cycle (Marković et al., 2021). For F. thunbergii, bulblets chilled at 5℃ for 5 weeks and larger than 10 mm achieved 100% sprouting after transplantation, showing that storage protocols can be standardized around bulb size and chilling duration. Related Fritillaria studies also show that bulbs are often stored at 4℃ before regeneration or acclimatization to improve regeneration capacity and dormancy breaking, while successful bulblet systems depend on low-temperature pretreatment, rooting, and ex vitro enlargement (Marković et al., 2023; Muraseva and Novikova, 2018). Direct evidence for mechanized production in F. thunbergii is limited in the supplied literature, but the available studies consistently support the technological logic of integrating standardized propagules, cold-chain dormancy management, uniform field planting, and scalable acclimatization, which are the biological prerequisites for later mechanized transplanting, harvesting, grading, and handling (Sharma et al., 2023).

5.3 Promoting the development of the Fritillaria thunbergii industry through the application of high-quality bulbs

Applying high-quality bulbs can directly strengthen the F. thunbergii industry because the crop faces high market demand but persistent production bottlenecks related to unstable yield, reduced medicinal quality under yield-oriented cultivation, and inefficient expansion systems (Sui et al., 2021; Liu et al., 2025). High-quality bulbs should be understood as bulbs that combine strong propagation performance, disease resistance, and high alkaloid accumulation, as exemplified by “Zhebei 3,” whose average yield reached 5 095.5 kg/hm², bulb proliferation rate 261.2%, propagation coefficient about 1:2.6, and peimine plus peiminine content 0.172 2% (Jiang et al., 2019). High-quality starting bulbs also support varietal upgrading and molecular breeding, because bulb development differs among cultivars and is associated with genes such as FtGGPS, which regulates bulb development through GA and ABA dynamics (Xu et al., 2026). At the germplasm level, breeding methods that shorten selection cycles and improve heat resistance, propagation coefficient, and absolute yield can further expand the supply base for industrial seed bulbs.

Industrial promotion also depends on proving and preserving product quality from bulb to market. F. thunbergii bulbs have broad pharmacological value and are used medicinally for cough, inflammation, bronchitis, and related disorders, so stable alkaloid quality is central to industry credibility and market expansion (Nile et al., 2021; Liu et al., 2025). Quality control systems based on HPLC-ELSD fingerprinting and multicomponent analysis can distinguish production origins and support standardized evaluation of commercial bulbs and propagation materials (He, 2021). Artificial cultivation and in vitro propagation also have strategic value beyond productivity, because they reduce pressure on wild Fritillaria resources, improve supply security, and fit the broader trend toward sustainable domestication of medicinal bulb crops (Qu et al., 2022). Therefore, the large-scale application of high-quality bulbs is not only a technical measure for raising yield and quality, but also a core pathway for strengthening regional brands, stabilizing medicinal standards, and promoting the sustainable modernization of the F. thunbergii industry.

6 Current Challenges and Future Development Directions

6.1 Improving bulb propagation efficiency and large-scale supply capacity

A central constraint on the large-scale supply of Fritillaria thunbergii bulbs is that conventional vegetative propagation remains inherently slow, while seed reproduction takes several years and therefore cannot rapidly expand elite planting material. This supply problem is economically important because market demand for dried F. thunbergii bulbs is high, yet production systems still struggle to deliver stable yield and quality at industrial scale (Sui et al., 2021; Cheng et al., 2023; Liu et al., 2025). The most immediate development direction is therefore to integrate conventional seed-bulb propagation with rapid multiplication systems based on bulb scales and tissue culture, which can greatly raise multiplication efficiency from limited source material (Marković et al., 2021). In F. thunbergii, bulb-scale culture already supports this transition, because scale sections on optimized MS medium produced 13.7 bulblets per explant and formed leaves and roots within 12 weeks.

Improving propagation efficiency also requires solving the linked bottlenecks of dormancy release, sanitary control, and field enlargement. In fritillaries, in vitro bulbs enter dormancy and cannot resume normal growth without low-temperature treatment, making dormancy management one of the main limiting steps in rapid multiplication (Marković et al., 2021). For F. thunbergii, cold treatment at 5℃ for 5 weeks enabled 100% sprouting of bulblets larger than 10 mm, showing that post-culture handling can be standardized to improve transplant success. Sanitary risk is another obstacle, because repeated use of mother bulbs can transmit viral and fungal infection to daughter bulbs, while field blight caused by Fusarium oxysporum has already reached 20~25% incidence in Zhejiang and can rot whole bulbs within days (Xu et al., 2022). Future large-scale supply systems should therefore combine pathogen-free micropropagation, resistant cultivar selection, and agronomic optimization, especially potassium and organic nutrient management, which increase yield, quality, and economic return while supporting more reliable bulb enlargement in the field (Sui et al., 2021; Huang et al., 2024).

6.2 Improving bulb quality evaluation and standardization systems

A major challenge in bulb standardization is that F. thunbergii quality varies with geographic origin, cultivation conditions, and post-harvest handling, which makes it difficult to define a single stable quality benchmark (Wang et al., 2023). Current evidence shows that origin authentication remains necessary: Zhejiang samples clustered together in HPLC-ELSD fingerprint analysis, whereas material from Nantong, Jiangsu separated from Zhejiang samples, likely because of different cultivation environments (He, 2021). A stronger future standardization system should therefore integrate external morphology with internal chemistry instead of relying on either alone (Zhang et al., 2026). This is feasible because bulb morphology and chemistry are both discriminative: among cultivated Fritillaria species, short bulb diameter was the most informative morphological identifier, while alkaloid and saponin contents helped distinguish morphologically similar materials.

Future quality evaluation should also move beyond a small number of marker compounds toward multicomponent and spatially resolved assessment. LC-MS chemometrics differentiated Zhejiang from non-Zhejiang Fritillariae Thunbergii Bulbus and identified 11 alkaloids as characteristic markers that correlated significantly with external morphological traits (Zhang et al., 2026). Processing studies further show that quality markers are not fixed across all product forms, because different processing methods altered steroidal alkaloid composition and revealed zhebeininoside and imperialine-3-β-D-glucoside as new control indicators (Shi et al., 2022). Quality standards should also account for within-bulb heterogeneity, since the outer bulb layers are enriched in total alkaloids, peimine, and flavonoids, whereas the inner layers accumulate more sucrose and starch (Wang et al., 2026). The most useful standardization framework is therefore a full-chain system linking morphology, fingerprinting, multicomponent quantification, origin tracing, and process control, consistent with broader herbal-medicine guidance that calls for molecular authentication, real-time monitoring, and shared industry standards across cultivation, harvesting, processing, and quality control (Wang et al., 2023).

6.3 Prospects of digital management and precision production technologies

Digital management and precision production technologies offer a realistic next step for F. thunbergii because the crop’s quality and yield respond strongly to local variation in nutrients, light, disease pressure, and soil microecology (Huang et al., 2024; Liu et al., 2026). Precision agriculture research shows that IoT and AI can support real-time monitoring and data-driven decision-making, with soil, optical, and stress sensors already being used to optimize irrigation, fertilization, and pest management in crop systems (Miller et al., 2025; Mansoor et al., 2025). For F. thunbergii, this approach is especially relevant because potassium status can already be diagnosed dynamically through a potassium nutrition index based on leaf K concentration, providing a clear entry point for sensor-assisted nutrition management. Digital management could also improve ecological cultivation strategies by enabling site-specific regulation of shading and fertilization, which is important because shading raises active ingredient content but reduces biomass, while potassium under shading partly restores yield and improves medicinal performance (Liu et al., 2025).

The main future direction is to connect sensing, modeling, and field operations into integrated production platforms. Remote sensing and UAV-based systems are already widely used in precision agriculture for crop monitoring, nutrient management, disease detection, and yield prediction, although performance still depends on image resolution, growth stage, and environmental conditions (Sishodia et al., 2020). These tools could support F. thunbergii by enabling earlier disease detection, more reproducible field diagnosis, and simpler decision workflows for bulb fields, where current disease losses can be rapid and severe (Xu et al., 2022). Broader IoT work suggests that future systems will likely include digital twins, 5G or LPWAN-enabled connectivity, scalable sensor platforms, and AI-assisted prediction, but adoption will depend on lowering costs, improving usability, and addressing data ownership and cybersecurity concerns (Mansoor et al., 2025). In F. thunbergii, the long-term goal should be a precision production system that links propagation batches, storage conditions, nutrient diagnosis, disease warning, and quality fingerprint data, so that high-quality bulbs can be produced with greater consistency, lower waste, and stronger traceability across the full industrial chain (Wang et al., 2023; Liu et al., 2026; Zhang et al., 2026).

7 Conclusion

Bulb propagation remains the fundamental production pathway for F. thunbergii, because bulb reproduction has historically been the main domestication method in Fritillaria, has been commercially practiced in China for centuries, and is much faster than seed-based reproduction, which generally requires more than five years. At the same time, conventional vegetative propagation alone cannot meet modern industrial demand, because only a few daughter bulbs are produced annually from each mother bulb, conventional propagation is economically slow, and infected mother bulbs can transmit viral or fungal problems to progeny. The practical solution supported across studies is to combine field bulb propagation with rapid in vitro multiplication, since bulb-scale culture in F. thunbergii can produce an optimum of 13.7 bulblets per explant within 12 weeks, while young stem or node-bud explants can reach about 20-fold multiplication under suitable kinetin conditions. Stable production also depends on cultivar improvement and physiological regulation, as “Zhebei 3” showed higher yield, a bulb proliferation rate of 261.2%, a propagation coefficient of about 1:2.6, and stronger soft-rot resistance, while mechanistic work indicates that genes such as FtGGPS and ABA- and GA-related regulation are involved in bulb development and yield formation.

A standardized propagation system is necessary because F. thunbergii quality is highly sensitive to cultivation conditions, nutrient supply, geographic origin, and bulb developmental status. Fertilization studies show that standardization can improve both output and medicinal quality: organic fertilizer increased yield to 2.70 kg/m² while producing high peimine and peiminine contents, potassium fertilization increased bulb yield, quality, and net income, and an optimal K range of about 108.4~128.0 kg K₂O/hm² or a practical target of 120 kg K₂O/hm² was repeatedly supported. Standardization must also extend to quality evaluation, because HPLC-ELSD fingerprinting distinguished F. thunbergii from related species and showed clustering among Zhejiang samples, while LC-MS chemometric analysis identified 11 alkaloid markers and linked external morphology with internal chemical quality. Together, these findings support a propagation standardization framework that integrates elite cultivar selection, seed-bulb grading, nutrient diagnosis through leaf K-based indices, and coordinated morphological and chemical assessment so that propagation materials and medicinal bulbs can be managed under the same quality logic.

Future development of the F. thunbergii industry will depend on technological innovation that simultaneously expands bulb supply, protects wild resources, and improves ecological and economic sustainability. Tissue culture and morphogenesis technologies are central to this transition because they enable year-round multiplication from small explants, can use bulb scales as highly effective starting material, and are suitable for large-scale propagation when hormone balance, explant type, and dormancy management are optimized. Dormancy release remains a key technical bottleneck, but cold treatment at 5℃ for 5 weeks enabled 100% sprouting of F. thunbergii bulblets larger than 10 mm, showing that propagation, storage, and transplant establishment can be linked into a controllable production chain. Sustainability-oriented innovations are also expanding beyond classical propagation, because biochar plus organic fertilizer improved understory yield, total alkaloids, soil nutrients, and rhizosphere microbial structure, shading plus potassium increased active ingredient accumulation while mitigating biomass loss, and endophytic bacteria from F. thunbergii showed potential for nutrient promotion and biocontrol against Fusarium pathogens. Overall, the most promising path is an integrated system that combines rapid propagation, standardized quality evaluation, and ecological precision cultivation, thereby supporting the large-scale, high-quality, and sustainable modernization of F. thunbergii production.

Conflict of Interest Disclosure

The authors affirm that this research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest.

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