The Sanqi (Panax Notoginseng (Burk.) F.H.Chen) flower is often used as a medicinal material, tea drink and food additive, thanks to its unique non-volatile and volatile organic compounds (VOCs) (Zhang et al., 2018; Yang et al., 2017; Chen S. Y. et al., 2022). It demonstrates significant efficacy in regulating the cardiovascular system, exhibiting anti-inflammatory effects, possessing antioxidant properties, providing neuroprotection, and improving metabolic diseases (Huang et al., 2023; Zhou et al., 2019; Liu J. C. et al., 2023). Sanqi flowers have a long history of consumption and are considered an excellent source of vitamins, minerals, proteins and amino acids, making them a promising new food ingredient (Yang et al., 2017). Currently, Sanqi flowers are used to brew tea and to enhance the flavour and health benefits of various liquids, including soups and beverages. They can also be used to flavour dishes such as egg and flower cakes. Ornamental plant floral fragrances repel herbivores, resist pathogens, protect flowers, attract pollinators, facilitate plant communication, and enhance aesthetic appeal (Unsicker et al., 2009; Li et al., 2022) (Unsicker et al., 2009; Li et al., 2022). Medicinal plant floral fragrance not only maintains the aforementioned roles but also releases aromatic compounds signaling flower quality, further elevating therapeutic value (Liu et al., 2024). Consequently, the study of floral fragrance compounds in Sanqi flowers is of great significance, as it can provide insights into their potential health benefits and applications in the food and pharmaceutical industries.

Organic cultivation improves the nutritional value, sensory quality and safety of agricultural products (Maggio et al., 2013), and for medicinal herbs, it boosts key chemical content, reduces pesticide residues, and stabilizes aroma and medicinal effects (Zhang et al., 2025). For instance, organic management elevates flavonoid, saponin, and polysaccharide levels in Sanqi flowers (Li et al., 2025b), and their VOC profiles (mainly terpenes, alkynes, and aromatic hydrocarbons) contribute to the distinctive fragrance (Chen X. F. et al., 2022). Terpenoid compounds, due to their diverse fragrances and biological activities, have extensive applications in the food industry, such as being used as natural flavourings and essences, antioxidants and preservatives, and functional food ingredients (Fan et al., 2023; Carson et al., 2006). Furthermore, Terpenes in Sanqi flowers from the forest understorey also have medicinal value: 3-carene, Germacrene D, and spatulenol modulate antibacterial activity, defense mechanisms, pollination, and anti-inflammation, respectively (Li et al., 2021), while α-guaiene and β-copaene relieve cough and phlegm (Lv et al., 2005) and exhibit antioxidant properties (Usman and Ismaeel, 2020). Different varieties and cultivation practices significantly influence the biosynthesis of VOCs and flavonoids in Sanqi flowers (Chen X. F. et al., 2022; Li et al., 2024b). However, despite the recognized importance of VOCs in Sanqi flowers, there is a significant lack of comprehensive research into how flowering periods and cultivation systems affect VOCs.

Flowering stages and geographical environments significantly shape floral fragrance profiles, with VOC variation across blooming stages driven by physiological, genetic, and environmental factors (Ru et al., 2025; Wang et al., 2025; Song et al., 2025; Du et al., 2022). On one side, enzyme activity and metabolic adjustments mediate VOC synthesis and release; on the other, gene regulatory networks control flowering timing to ensure favorable blooming conditions (Li et al., 2024c). For instance, transcription factors such as those from the MADS-box gene family play crucial roles in floral organ development (Li et al., 2023). Simultaneously, Aromatic compounds vary across flowering stages and flower sections, reflecting the plant’s adaptive pollinator attraction strategies (Zhou et al., 2024). Furthermore, abiotic factors such as climate (including temperature, humidity, and light), soil composition, altitude, and nutrient availability significantly influence the synthesis and release of VOCs (Chen X. F. et al., 2022; Li et al., 2024a), as VOCs are temperature-sensitive and drive dynamic changes in floral components. The emission rate of VOCs accelerates with rising temperatures (Hu et al., 2023; Fu et al., 2017), but this relationship is not a simple linear increase (Sagae et al., 2008). Previous studies have revealed that the VOCs of Sanqi flowers are significantly influenced by genetic factors (Chen X. F. et al., 2022). However, limited information was available regarding the mechanisms by which abiotic factors affect the synthesis and release of VOCs. Therefore, in-depth research into the impact of abiotic factors on the VOCs of Sanqi flowers holds significant theoretical value and practical application significance for optimizing cultivation environments and enhancing medicinal quality.

Organic rather than conventional management of Sanqi not only improves its quality (Li et al., 2024b), but also alter soil metabolites (He et al., 2025), increase microbial diversity (Zhao et al., 2025; Hei et al., 2025), enhance soil fertility, and reduce heavy metal content (Liu et al., 2025). Moreover, Pinus armandii and Pinus yunnanensis are primarily suitable for Sanqi cultivation. However, the specific impacts of Sanqi-P. armandii (SPA) and Sanqi-P. yunnanensis (SPY) agroforestry systems on the VOCs in Sanqi flowers are not yet fully understood. Thus, these two systems were the focus of this study. By integrating headspace-solid-phase micro-extraction (HS-SPME) technology with gas chromatography-mass spectrometry (GC), the characteristics of VOCs in Sanqi flowers were systematically analyzed across flowering periods and cultivation practices. The objective of this study is twofold: (1) to investigate the effects of flowering periods (unopened, half-opened, fully opened stages) and two distinct agroforestry systems (SPY and SPA) on the composition, content, and characteristic VOCs of Sanqi flowers, and to unravel the key environmental factors and their interaction mechanisms regulating VOC biosynthesis and emission; (2) to provide practical guidance for optimizing cultivation practices and determining the optimal harvesting time of Sanqi flowers, thereby supporting the efficient utilization of Sanqi flowers in functional foods, beverages, and natural food additives with enhanced sensory and medicinal-edible qualities.

A total of 53 VOCs, predominantly terpenoids, have been observed in the flowers of various Sanqi genotypes [3]. Similarly, our research has identified 60 and 55 VOCs in the Sanqi flowers of SPY and SPA agroforestry systems, respectively, with terpenes being the predominant components. Sanqi flowers, when managed with conventional practices, primarily contain various sesquiterpene compounds, such as spathulenol, germacrene D, bicyclic germacrene, and α-panaxine (Li et al., 2017). However, our study revealed elevated levels of germacrene D, β-ocimene, and β-elemene in the Sanqi flowers. This finding contradicts our earlier results, which indicated that 3-carene and germacrene D were the primary VOCs during full flowering (Chen X. F. et al., 2022). On the one hand, organic management practices, which involve no application of pesticides and fertilizers, can improve the soil environment and enhance the volatile VOCs of medicinal herbs (Maggio et al., 2013). On the other hand, Sanqi flowers are typically harvested in the first and second years. Consequently, the timing of these harvests is the primary reason for the variation in germacrene D, β-ocimene, and β-elemene content. β-Ocimene, Germacrene D, and β-Elemene play vital roles in the food industry. These compounds not only enhance food flavor and sensory appeal but also demonstrate antioxidant and antimicrobial properties. For example, β-Ocimene and Germacrene D are widely used in flavor formulation for food and beverages (Kou et al., 2024; Pratama et al., 2022), as well as in spice blends for alcoholic beverages and premium processed foods (Thang et al., 2014; Kazemeini et al., 2021). Meanwhile, β-Elemene serves both as a direct flavor additive in food products and as an essential component in spice mixtures (Chen S. Y. et al., 2022; Sieniawska et al., 2018). Additionally, both β-Ocimene and β-Elemene exhibit remarkable antioxidant properties that effectively inhibit lipid oxidation and free radical formation, which are vital for extending food shelf life and maintaining freshness (Bensid et al., 2020; Xiang et al., 2024). Germacrene D’s broad-spectrum antibacterial properties further enhance food hygiene standards by protecting moist foods from various spoilage-causing bacteria (Thang et al., 2014). Additionally, the compounds β-ocimene, germacrene D, and β-elemene possess medicinal properties. For instance, β-ocimene can induce plant defense responses (Kang et al., 2018), facilitate inter-plant communication (Cascone et al., 2015), enhance crop resistance (Xie et al., 2025), and regulate secondary metabolites (Xiao et al., 2020). Germacrene D plays a vital role in pest and disease resistance (Caselli et al., 2021), interplant communication (Prosser et al., 2004), the composition of essential oils, and antibacterial properties (Rguez et al., 2023). β-Elemene inhibits tumor cell growth and exhibits anti-inflammatory properties. Consequently, functional beverages or dietary supplements containing β-Elemene have been proposed to aid in boosting immunity and may possess further anti-cancer potential (Chen S. Y. et al., 2022). As the demand for natural food additives continues to rise, terpenoid compounds such as β-ocimene, germacrene D, and β-elemene have emerged as promising candidates for next-generation additives (Chen S. Y. et al., 2022). This is thanks to their sustainable potential and natural, plant-derived properties.

The flowering stage significantly affects the types and concentrations of VOCs, with these changes reflecting the plant’s physiological state, ecological functions, and interactions with the environment (Liu J. C. et al., 2023). Our research demonstrated that the VOCs in Sanqi flowers progressively increased during the flowering period, peaking at full bloom. This finding aligns with observations that Michelia crassipes petals contain the most volatile components during full opened flowering stage. This is primarily attributed to the emission of VOCs from flowers, which is influenced by the plant’s growth stage, characteristics of floral organs, variations in gene expression, epigenetic modifications, and external environmental conditions (Picazo-Aragonés et al., 2020; Li et al., 2025b). Simultaneously, various flowering stages impact not only the total quantity and composition of VOCs but also yield compounds that are unique to a specific stage. For instance, phenylpropanoids/styrene was abundant in D. chrysotoxum during the initial blooming stage, while isoprenoid-like compounds were more prevalent at the full blooming stage. The concentration of germacrene D in sanqi flowers first increased and then decreased, peaking at the half-bloom stage. Moreover, the highest concentration of β-ocimene was found in unopened Sanqi flowers. This is because different flowering periods regulate the genes responsible for synthesising germacrene D and β-ocimene (Li et al., 2022). In addition, the unique VOCs that differentiate the flowering stages were trans-Nerolidol, (E)-4,8-Dimethylnona-1,3,7-triene, and γ-Muurolene from the PYS system, and Cubenene, Espatulenol, and Bicyclogermacrene from the PAS system. In summary, by utilizing our knowledge of the VOCs emitted at different stages of flowering, we can harvest Sanqi flowers at the optimal time to select specific VOCs for incorporation into food products.

Plants in various geographical regions, even those of the same species, may display significant variations in their floral fragrance components. This phenomenon is attributed to abiotic factors such as climate conditions, soil composition, altitude, and nutrient availability (Campbell et al., 2018; Luizzi et al., 2021; Wu et al., 2024). The PCA analysis revealed that the PYS and PAS systems significantly influenced the content and composition of VOCs, consistent with findings from other studies (Li et al., 2022). High temperatures can enhance the activity of enzymes involved in VOCs synthesis, further accelerating the evaporation of VOCs (Barman and Mitra, 2021). Moreover, humidity significantly influences the quality traits of blackcurrant fruits, including the accumulation of VOCs (Pott et al., 2023). The RDA analysis results further confirmed that humidity being the primary factors affecting the VOCs in Sanqi flowers. Moreover, the humidity were higher in the PYS system than in the PAS system (Supplementary Table S2). Hence, higher humidity are key factors influencing the VOCs in the flowers of Sanqi, since the PYS system maintains higher longer rainy seasons. Meanwhile, the composition and activity of soil microbial communities significantly influence plant growth and metabolism, which in turn affects the production of VOCs (Sun et al., 2020). Research has shown that the composition of soil microbial communities is influenced by the species of pine employed in the Sanqi-pine agroforestry system. Furthermore, endophytic bacteria can be transmitted from pine trees to Sanqi plants, thereby influencing the release of VOCs (Jia et al., 2022; Li et al., 2024b). Additionally, the availability of nutrients in the soil influences the phenotypic plasticity of VOCs in the plant (Li et al., 2025a). In conclusion, the composition and content variations of VOCs in Sanqi flowers result from the combined effects of abiotic factors (such as humidity and temperature) and biotic factors (like soil microorganisms and endophytes). These factors regulate Sanqi metabolic pathways and enzyme activities, ultimately leading to the distinct characteristics of VOCs in different geographical regions or agroforestry systems. Future research could further integrate transcriptomic and metabolomic approaches to elucidate the molecular mechanisms underlying how humidity, temperature, and microorganisms influence the VOCs synthesis in Sanqi flowers. This would provide theoretical foundations for optimizing product quality through environmental regulation or microbial intervention strategies.

A total of 60 and 55 VOCs were identified in Sanqi flowers from the SPY and SPA agroforestry systems, respectively, with terpenoids as the predominant component class. Germacrene D and β-ocimene were more abundant in the SPY system, whereas β-elemene was richer in the SPA system. The cultivation system was the primary factor shaping VOC composition, while humidity (followed by temperature) was the key environmental driver. Understanding the variations in VOC profiles across flowering periods and cultivation regimes offers practical guidance for optimizing Sanqi flower harvesting, supporting their effective utilization in functional foods.