From traditional knowledge to multi-omics: the future of biotechnology-driven ethnobotany in Hainan Island, China

Hainan Island, the southernmost province of China (Fig. 1a), exhibits a distinctive tropical and subtropical climate that significantly influences its biodiversity and agricultural practices. Unlike other southern regions with tropical fragments (e.g., southern Yunnan and Guangxi), 42.5% of Hainan Island's land area falls within the tropical and subtropical zone. The island experiences an annual average temperature of 23–25 °C and mean annual rainfall exceeding 1,600 mm, creating favorable conditions for diverse plant species, including native and economically significant crops such as coconuts^[1]. Hainan's unique geographical and climatic conditions also shape its ecological landscape. The island hosts the most extensive and well-preserved tropical forests in China, supporting higher levels of native plant endemism and diversity than fragmented tropical areas in Yunnan and Guangxi. For instance, Hainan is home to over 6,000 vascular plant species (of which about 15% are endemic), far surpassing the tropical plant diversity of Guangxi's coastal areas and exceeding the endemic species ratio of Yunnan's Xishuangbanna^[2,3].

Figure 1. 

Maps of Hainan Province: terrain, ethnic groups, forest coverage, ethnic population, and its location in China. (a) The location of Hainan in China. (b) Topographic map of Hainan. (c) Distribution of tropical rainforest national parks in Hainan. (d) Map of minority languages in Hainan. (e) Surface coverage map of Hainan. The map inspection number of (a) is GS (2024) 0650, and this map was supervised by the Ministry of Natural Resources of China. The inspection numbers of (c) and (d) are GS(2024)056 -survey qualification certificate No. 1100471, and these maps were supervised by Hainan Provincial Bureau of Surveying, Mapping, and Geographic Information, data acquired from the National Platform for Common Geospatial Information Services of China. All maps used in this figure are based on the official Chinese map provided by the Standard Map Service System of the Ministry of Natural Resources of China (http://bzdt.ch.mnr.gov.cn).

Culturally, Hainan's ethnic diversity further enhances its uniqueness. Unlike Yunnan's diverse ethnic groups with cross-border cultural connections or Guangxi's Zhuang-dominated ethnic landscape, Hainan is home to the Li people and Miao, Hui, and Yao communities that have developed isolated, island-specific ethnobotanical knowledge over millennia^[4]. For example, the Li people's utilization of over 500 plant species for medicine, food, and crafts—such as Mallotus furetianus (Zhegu tea) and Broussonetia papyrifera (Li bark cloth raw material)—is distinct from the ethnobotanical practices of Yunnan's Dai or Guangxi's Zhuang, which are shaped by continental cultural exchanges^[5,6]. This unique blend of intact tropical ecosystems and isolated ethnic traditions makes Hainan a globally significant site for ethnobotanical research—offering insights into human-plant interactions.

Ecologically, Hainan's central and southern mountainous areas (e.g., Wuzhishan and Jianfengling) are identified as key hotspots for plant endemism^[2]. Hainan's unique geographical and climatic conditions also shape its ecological dynamics. The spatial distribution of plant diversity is largely driven by environmental factors such as temperature, precipitation, and soil composition. Notably, climate change is influencing agricultural suitability on the island, with studies predicting shifts in optimal cultivation zones for crops like green oranges^[3]. Additionally, the presence of non-native species, mainly introduced through human activities, poses ecological challenges, as these species compete with native flora and alter biodiversity patterns^[7].

These ecological cultural characteristics highlight Hainan's irreplaceable value: it is not only a repository of China's most intact tropical biodiversity but also a living archive of unique ethnic botanical knowledge, making it a critical focus for ethnobotanical research and conservation.

Besides these unique plantations, Hainan is home to 55 officially recognized ethnic minorities, including the Li, Miao, Hui, Zhuang, and Yao, which significantly enriches the region's cultural diversity, traditional craftsmanship, and economic activities^[8]. The Li, the island's earliest settlers with a population exceeding 1.2 million, are renowned for their UNESCO-listed Li ethnic brocade (Li Jin), traditional agriculture, and medicinal plant knowledge^[9]. The Miao, descendants of Ming Dynasty soldiers, excel in silverware processing, brocade weaving, and herbal medicine^[9]. The Hui, with roots tracing back to Persian and Arab merchants, maintain Islamic traditions in religion, cuisine, and clothing, primarily in Yanglan Town, Sanya^[10]. The Zhuang, engaged in agriculture, are culturally known for their folk songs and dances, sharing affinities with their Guangxi counterparts^[11]. The Yao, residing in the northwest, are experts in traditional embroidery and medicinal plant knowledge, contributing to local healthcare practices^[4]. Despite modernization and tourism challenges, these communities play a vital role in preserving Hainan's cultural and ecological heritage, necessitating increased conservation efforts^[12].

These ethnic minorities have developed extensive traditional knowledge regarding plant utilization, particularly in food, medicine, and material culture. The Li people have a rich ethnobotanical tradition, utilizing over 500 species of plants for medicinal, culinary, and utilitarian purposes^[6]. Among these, medicinal plants play a significant role, with 282 species identified in Li traditional medicine, used primarily for treating ailments such as rheumatism, gastrointestinal disorders, and traumatic injuries^[13]. The Miao and Hui also employ plant-based medicine, with many species shared with traditional Chinese medicine (TCM) and local folk practices^[14]. In addition to medicinal uses, plants play a crucial role in food and cultural practices. The Li people cultivate indigenous crops such as mountain rice (Shanlan upland rice) and use wild plants to create traditional rice dishes, including herbal soups and fermented foods. The Miao ethnic group is known for using wild herbs and spices in cuisine, while the Hui integrate their Islamic dietary customs with local plant resources^[5]. Furthermore, many ethnic groups in Hainan utilize plant materials for handicrafts, such as bamboo weaving, textile dyeing, and wood carving, preserving traditional craftsmanship and cultural heritage^[15]. Despite the richness of ethnobotanical knowledge, modernization and environmental degradation pose challenges to the preservation of traditional practices. The increasing commercialization of ethnic cultural heritage, particularly in tourism, has altered the way indigenous knowledge is transmitted, with some concerns over the authenticity and sustainability of cultural preservation efforts^[12]. Efforts to document and protect traditional botanical knowledge remain crucial to maintaining the cultural and ecological diversity of Hainan.

Situated within the tropical zone, Hainan Province represents China's most biodiverse region and harbors several distinctive ethnic minority groups. The areas where ethnic minorities live in compact communities in Hainan Province highly overlap with the mountainous regions with high biodiversity in Hainan Province, as demonstrated in Fig. 1b–e. To investigate the traditional botanical knowledge and plant utilization patterns among these indigenous communities, researchers in Hainan have implemented ethnobotanical approaches, establishing a novel framework for studying the intricate relationships between local ethnic groups and their floristic environment. Ethnobotany is an interdisciplinary field that examines the complex relationships between humans and plants. The term was first introduced by John William Harshberger in 1896, originally defined as 'the study of plants used by aborigines'^[16]. Over time, its scope has expanded significantly, encompassing various dimensions of human-plant interactions.

The development of global ethnobotany can be summarized as follows: In its early stages (19^th to early 20^th century), ethnobotany emerged from natural history and plant taxonomy, with scientists beginning to document indigenous traditional knowledge of plants and applying it to medical and agricultural research^[17]. During the modern phase (mid-20^th to early 21^st century), ethnobotany integrated with disciplines such as ecology, chemistry, and pharmacology, driving research on traditional medicinal plants and the development of new drugs^[18]. In the contemporary era (21^st century to present), ethnobotany has increasingly focused on sustainable development, biodiversity conservation, and cultural preservation, while utilizing modern technologies such as DNA analysis and remote sensing to enhance research depth^[19]. This evolution reflects the field's growing interdisciplinary nature and its critical role in addressing global challenges related to environmental and cultural sustainability.

Based on the historical development of ethnobotanical research in Hainan, the earliest systematic studies can be traced back to the late 1980s. The pioneering work by Pei Shengji laid the theoretical foundation for ethnobotanical research in southern China, although it primarily focused on Yunnan Province^[20]. Subsequently, scientists from Hainan conducted the first specialized ethnobotanical investigation on the Li people's medicinal plant use in Hainan Island, published in Economic Botany, marking a significant milestone in Hainan's regional ethnobotany^[21]. These seminal works collectively established the academic framework for understanding the traditional botanical knowledge systems of Hainan's ethnic minorities, which have been developed and preserved over centuries. It also explores how different ethnic groups perceive, utilize, conserve, and manage plant resources. It includes research on the economic, medicinal, ecological, and cultural significance of plants across diverse communities.

The people of Hainan make extensive use of the region's unique plants in various aspects of life. These plants are employed in clothing, food, shelter, transportation, and medicine, which reflects the residents' deep understanding and utilization of the natural resources. Several highly representative ethnobotanical plants were selected and presented in Fig. 2 below.

Figure 2. 

Diagram of the ten representative ethnic plants in Hainan. All edible plants listed can act both as medicine and food in the traditional Hainan medicine system.

In Hainan Island, China, ethnic minority groups, such as the Li and Miao people, have a long tradition of using local plants for medicinal purposes. Their knowledge, passed down through generations, is deeply rooted in the island's rich biodiversity^[22]. These communities rely on wild herbs, roots, leaves, and barks to treat various ailments, from common colds to chronic conditions^[23]. Their practices often combine spiritual beliefs with natural remedies, emphasizing harmony with nature^[23]. While modern medicine is increasingly accessible, many still prefer traditional plant-based treatments due to their cultural significance and perceived effectiveness^[14]. However, this indigenous knowledge faces challenges from deforestation and cultural erosion. Efforts are being made to document and preserve these practices as part of Hainan's intangible cultural heritage. In recent years, remarkable progress has been made in the study of medicinal ethnobotany in Hainan Province, mainly focusing on the Li ethnic group and other ethnic groups. The Li people have a long-standing history of using medicinal plants. Studies show that they utilize 50 species from 36 families, and the Run dialect group of the Li people uses 282 species from 89 families and 222 genera^[13]. The most common families are Leguminosae (14%), Compositae (6%), and Euphorbiaceae (6%). The main preparation methods are decoction (84%), crushing (38%), and ointment (34%), mainly for treating bleeding, pain, gastrointestinal diseases, and trauma^[5]. This paper summarizes the ethnic minority medicinal plants recorded in various historical materials in Hainan Province, as shown in Table 1. The core differences in rheumatism-treating medicinal plant selection between the Li and Miao ethnic groups stem from their distinct ecological niches and cultural practices. The Li, residing in Hainan's central-southern mountains, favor Leguminosae and Euphorbiaceae plants, prepared as decoctions/ointments to adapt to damp-heat environments. In contrast, the Miao inhabit more isolated highlands with shamanistic traditions, emphasizing diverse herbaceous plants with spiritual elements, showing unique anti-inflammatory preferences alongside overlaps^[24]. The Li's tropical forest proximity supports endemic damp-resolving shrubs, while the Miao, influenced by Ming migrations, integrate cross-regional herbs linked to their weaving/silverware cultures to combat humid-island parasitic infections. Yet overall similarity remains high due to shared biodiversity hotspots, reflecting the common adaptation of local ethnic groups to the island's unique ecological and climatic conditions^[24].

The application of ethnobotanical plants in a health-promoting diet

In Hainan, ethnic minorities have long utilized local plants not only as medicine but also as tea, food, and flavorings, blending nutrition and health, as shown in Table 2. Wild herbs, leaves, and roots are often brewed into herbal teas, believed to aid digestion, detoxification, and general well-being. Many plants are incorporated into daily meals, either as staple ingredients or seasonal supplements, enhancing both flavor and nutritional value^[31]. Some aromatic or pungent plants serve as natural condiments, adding unique tastes to traditional dishes. In Baoting and Lingshui in Hainan Province (both are minority-inhabited regions), a recent ethnobotanical survey documented 26 species of wild edible vascular plants, encompassing 24 genera and 16 families. The majority (84.62%) of these species were identified as annual or perennial herbs, demonstrating a strong reliance on herbaceous flora in local dietary practices^[32]. Aboveground plant parts, such as leaves, stems, and young shoots, were the most frequently utilized components, suggesting a sustainable harvesting approach that allows for plant regeneration. Among various preparation methods, stir-frying emerged as the predominant culinary technique, reflecting both traditional cooking preferences and the practical suitability of these plants for high-heat preparation^[32].

Additionally, certain plants function as both food and medicine, consumed for their therapeutic benefits while providing sustenance, as shown in Table 2. For example, herbal teas (liáng chá), represent an important category of functional beverages widely consumed in southern China, especially in Hainan, Guangdong, and Guangxi. Documentation revealed that 222 ethnotaxa (representing 238 botanical taxa at species, variety, and subspecies levels) were utilized in liáng chá preparations^[33]. These taxa span 209 genera from 86 plant families, demonstrating significant biodiversity in this traditional pharmacopeia^[33]. Coconut water, a refreshing beverage documented by various ethnic minorities in Hainan, is widely cherished by the local people^[34]. These practices reflect a deep connection to nature, where diet and health are intertwined. However, modernization and habitat loss threaten this knowledge, prompting efforts to preserve these traditions as part of Hainan's cultural heritage.

Heavy metal content and toxic secondary metabolite testing have been conducted on the food safety of 'medicinal food homologous' plants like purslane (Portulaca oleracea) and fake konjac (Amorphophallus konjac) in Table 2. For purslane, studies in China have assessed bioaccumulation of metals like Cd, Pb, and Zn in contaminated soils, showing its phytoremediation potential but highlighting risks of elevated levels in edible parts, with recommendations for safe harvesting thresholds^[35]. For fake konjac, analyses have evaluated secondary metabolites such as alkaloids and their potential toxicity, confirming anti-tumor benefits but noting reductions in harmful compounds like β-glucuronidase through processing, ensuring safety in traditional uses^[36].

Heritage and cultural significance of ethnobotanical plants in Hainan

In Hainan, ethnobotanical plants play a vital role in the religious and cultural life of indigenous communities such as the Li and Miao peoples. These plants possess not only practical functions but also profound symbolic meanings, deeply embedded in rituals and traditional medicine, reflecting a worldview rooted in the harmonious coexistence between humans and nature. Archaeologists believe that coconuts were introduced and utilized by the ancient people of Hainan over two thousand years ago. With its majestic and tall appearance, the coconut tree is regarded by the people of Hainan as the 'hero tree', embodying justice and strength^[40]. These ethnobotanical traditions form the foundation of local religious practices and everyday life, while also representing a significant area of inquiry in ethnobotany and cultural anthropology^[14]. However, this invaluable knowledge is increasingly endangered by modernization and the erosion of traditional lifestyles. Therefore, systematic documentation, research, and preservation of Hainan's ethnobotanical heritage are essential for safeguarding indigenous wisdom, revitalizing ethnic cultures, and promoting sustainable ecological development. In ancient times, due to its geographical remoteness and distance from the Central Plains, Hainan failed to produce systematic medical books. Nevertheless, the knowledge passed down orally among the people has been preserved. However, the rapid social and economic development in Hainan poses a threat to the protection of Li ethnic medicines, leading to a decline in the use of medicinal plants and traditional knowledge. In the future, it is necessary to conduct a more comprehensive investigation of medicinal plant resources, study their chemical components and pharmacological effects, protect and inherit traditional knowledge, and explore sustainable utilization methods. Also, comparative studies with other ethnic groups' medicinal botany and research on the cultural connotations of medicinal plants are needed to further enrich the research in this field.

Hainan ethnic medicinal plants, primarily utilized by indigenous groups such as the Li and Miao, diverge markedly from TCM in their ethnobotanical foundations, therapeutic paradigms, and ecological adaptations. These distinctions arise from Hainan's unique tropical insular environment, contrasting with the mainland's heterogeneous monsoon climates, diverse ethnic amalgamations, and transitional floristic assemblages. Hainan's perennial tropical monsoon climate and oceanic influences foster plants adapted to damp-heat pathologies, emphasizing heat-clearing and dampness-resolving properties. This climatic divergence underscores Hainan's uniqueness in tropical resilience, complementing TCM by augmenting interventions for endemic humid ailments.

Ethnically, Hainan's isolated Li and Miao communities perpetuate oral, shamanistic traditions. This insular oral heritage imparts a distinctive shamanic vitality, enriching TCM with dynamic 'living prescriptions' for parasitic infections prevalent in island ecosystems. Floristically, Hainan's continental-island flora favors herbaceous and shrubby taxa in acidic, humid rainforests, diverging from TCM's root-rhizome dominance in subtropical transitions. These Southeast Asian-affiliated endemics form a 'maritime tropical pharmacopeia,' uniquely bolstering TCM's northern tonics with southern damp-resolving polysaccharides.

The current situation of ethnobotany in Hainan Island reflects a rich heritage of over 6,000 vascular plant species, with ethnic minorities like Li and Miao utilizing more than 500 species for medicine and diet, but facing threats from modernization, habitat loss, and cultural erosion. Progress includes biotechnological integrations like multi-omics for validating active compounds and conserving endangered species, supported by policies for sustainable development. From our perspective, the future lies in interdisciplinary collaborations to bridge traditional knowledge with precision ethnobotany, ensuring equitable benefit-sharing and climate-resilient practices to preserve this biodiversity hotspot.

The design and implication of policies

Current policies inadequately integrate traditional knowledge protection with biodiversity conservation, hindering the integration of culture-ecology. For instance, the cultural significance of Hainan Li's 'sacred forests' remains excluded from legal frameworks, leading to encroachment during development^[23]. The absence of legally binding benefit-sharing mechanisms further exacerbates inequities, as Li's medicinal knowledge is commercially exploited without fair community compensation. Furthermore, research funding and expertise are disproportionately concentrated in regions like Yunnan and Beijing, marginalizing critical areas such as Hainan^[41]. This spatial imbalance delays documentation of Li's 'swidden agriculture' and undermines evidence-based policymaking. Insufficient investment in academic infrastructure, evidenced by ethnobotany's exclusion from university core curricula, aggravates disciplinary marginalization and impedes talent cultivation^[42,43]. Finally, government efforts to communicate ethnobotany's socioecological value remain inadequate, perpetuating public perception of traditional practices as 'outdated customs'^[42,43]. Misconceptions about Li's swidden agriculture as 'primitive' overshadow its ecological merits, skewing policy toward modern intensive farming^[23]. Additionally, the lack of community empowerment mechanisms excludes Li residents from decision-making in sacred forest management, stifling integration of traditional governance into modern conservation systems^[23].

Hainan Province has established a comprehensive policy framework covering the entire industrial chain of medicinal ethnobotanical plants and southern medicinal herbs. The Hainan Provincial Development Plan for Southern Medicinal Herbs and Li Medicine Industry (2023–2030) explicitly aims to build the 'Top Ten Southern Medicinal Herbs' brand, with a target of exceeding 100,000 hectares of planting area by 2030. The Three-Year Action Plan for Accelerating High-Quality Development of Traditional Chinese Medicine Industry (2025–2027) proposes the construction of high-quality seed breeding bases and local processing centers, aiming to expand the planting area to over 66,667 hectares. The Interim Measures for the Protection and Management of Wild Plants regulates resource utilization, while standards such as the Geographical Indication Certification Trademark: Hainan Agarwood (Medicinal Agarwood) strengthen quality control. In terms of scientific research and innovation, the Implementation Plan for Comprehensively Deepening the Supervision Reform of Drugs, Medical Devices, and Cosmetics supports the research and development of in-hospital preparations, with a plan to promote the registration and filing of more than 15 preparations by 2027. In the evolving discipline of ethnobotany, quantitative metrics are paramount to elevating indigenous knowledge from anecdotal lore to empirical science, necessitating the establishment of standardized evaluation frameworks. Traditional indices such as the Use Value (UV) and Fidelity Level (FL) must be augmented with advanced quantitative ethnobotany indicators, including the Relative Importance Index (RI) and Informant Consensus Factor (ICF), to systematically assess plant utility across cultures. These metrics, calibrated against global databases like the Useful Plants Database, enable cross-cultural comparisons and validate therapeutic claims, fostering a robust, replicable paradigm that bridges ethnobotanical surveys with pharmacognostic validation.

Lagging research and technology related to ethnobotany

Critical gaps in the systematicness and technical depth of current ethnobotanical research in Hainan further constrain resource protection: (i) Lack of Systematic Research Frameworks. Current studies are largely scattered and topic-specific, failing to form a comprehensive research system. Research on ethnic plant use (e.g., Li bark cloth raw materials, Miao herbal tea) is often isolated from ecological and genetic studies. For example, while over 500 plant species used by the Li have been documented^[12], there is no systematic database linking their cultural use, genetic traits, and ecological functions—unlike Yunnan's Xishuangbanna, which has established a 'cultural-ecological-genetic' integrated ethnobotanical database^[38]. (ii) Insufficient Technical Depth in Research. Modern quantitative methods and biotechnologies are underutilized, limiting the scientific validation and application of traditional knowledge. For example, the hemostatic mechanisms of Dracaena cambodiana (used in Li medicine) remain unverified due to insufficient metabolomic studies, hindering its integration into modern pharmacology^[23]. Endangered endemic plants in Li sacred forests face extinction risks without tissue culture-based propagation^[43], while limited genomic sequencing obscures the genetic traits and adaptability of traditional crops^[44]. Despite its interdisciplinary nature (spanning botany, anthropology, and ecology), ethnobotany remains dominated by qualitative descriptions, lacking robust quantitative models. The carbon sequestration potential of Li swidden agriculture, for instance, cannot be quantified without integrating GIS spatial analysis and ecological-economic modeling^[23]. Disparities in disciplinary paradigms, such as anthropology's focus on cultural symbolism versus botany's species-centric approach, further fragment research outcomes^[43]. Key technologies for transforming traditional wisdom into sustainable productivity are underdeveloped. The eco-friendly fiber processing of Li bark cloth, though aligned with low-carbon principles, faces scalability challenges due to unresolved fiber modification techniques^[45]. Additionally, lagging digital technologies (e.g., blockchain) heighten risks of database tampering and resource exploitation, impeding intellectual property protection^[44]. Among the technologies mentioned, modern biotechnology brings the greatest benefits to ethnobotany and represents the future of this discipline. The following part will focus on introducing the potential applications of biotechnologies, especially multi-omics in ethnobotany.

As one of the most cutting-edge technologies in contemporary biological research, multi-omics synthesizes information from genomics, transcriptomics, proteomics, and metabolomics and provides a powerful toolkit for the innovation of plant germplasm resources in ethnobotany, with significant application value in the following aspects. By leveraging artificial intelligence and machine learning algorithms, such as graph neural networks, for predicting bioactive pathways. These approaches dissect polypharmacological interactions, as exemplified in studies correlating Ayurvedic formulations with molecular docking simulations. Such data-driven correlations not only substantiate empirical uses but also accelerate lead compound discovery, mitigating the translational gap between folklore and clinical trials. Ensuring the fidelity of germplasm conservation demands rigorous genetic stability assessments for regenerated plants, encompassing phenotypic diversity via morphometric analyses and molecular profiling through SSR and SNP markers. Comprehensive reviews underscore that SSR-based genotyping reveals clonal fidelity in micropropagated medicinal species like Withania somnifera, while SNP arrays detect subtle allelic variations, safeguarding against somaclonal mutations and preserving chemotypic integrity in ex situ repositories. Looking ahead, frontier research in medicinal plants converges on bioactive compounds and heritable traits, propelled by CRISPR-Cas9 gene editing for enhanced secondary metabolite yields, synthetic biology for de novo pathway engineering, and GWAS to map quantitative trait loci (QTLs) underpinning pharmacological potency. These innovations herald a precision ethnobotany era, harmonizing cultural heritage with biotechnological stewardship to sustain biodiversity and therapeutic innovation.

The rapid development of multi-omics technologies offers a completely new perspective for ethnobotany research, enabling the molecular-level elucidation of the pharmacological basis and mechanisms of traditional herbal medicines. Metabolomics, when integrated with genomics, transcriptomics, and proteomics data, is becoming a core methodology in ethnopharmacology research by leveraging multi-dimensional integration to analyze the biosynthesis pathways and metabolic networks of plant active compounds. Scholars in the eethnobotany field in Hainan have started to use this method in their research. The application of multi-omics technologies in Hainan ethnobotany spans multiple domains, including molecular identification of medicinal plants, active compound characterization, genetic improvement, and ecological conservation, thereby providing a scientific foundation for the modernization of ethnobotanical resources. For instance, Dracaena cambodiana, historically used for promoting blood circulation, has its resin (dragon's blood) documented in the Compendium of Materia Medica. Recent metabolomic studies employing LC-MS/MS have identified loureirin B as a key active compound, confirming its anti-inflammatory and anti-tumor properties^[46]. Furthermore, genomic research has elucidated the biosynthetic pathway of loureirin B and completed the whole-genome sequencing of D. cambodiana, revealing that the CYP450 gene family plays a pivotal role in the biosynthesis of its active constituents^[47]. Additionally, evolutionary studies suggest that D. cambodiana underwent rapid diversification during the Pleistocene epoch, significantly influenced by climatic fluctuations^[48].

The combination of Gas Chromatography-Mass Spectrometry (GC-MS), Liquid Chromatography-Mass Spectrometry (LC-MS), and Nuclear Magnetic Resonance (NMR) techniques allows researchers to accurately analyze the complex secondary metabolite profiles within plants. For instance, scientists utilized LC-MS and GC-MS in their study to delineate the spectral characteristics of medicinal plant metabolites, revealing key enzymatic nodes for terpenes, flavonoids, and alkaloids in antibacterial and antioxidant processes^[49]. Similarly, Karalija et al. systematically elucidated how exogenous elicitors activate defense metabolic pathways and promote the accumulation of medicinal secondary metabolites (such as phenolic acids and alkaloids) through a multi-omics and tissue culture integration strategy^[50].The combined analysis of LC-MS and transcriptomics further clarifies the pharmacological mechanisms of plant active components. For example, Omics Studies of Medicinal Plants pointed out that multi-omics can reveal the regulatory roles of MAPK and PI3K/Akt signaling pathways in medicinal plants, providing molecular evidence for their anti-inflammatory and anticancer activities^[51]. In a specific case, metabolomic research on Dracaena cambodiana (dragon's blood) showed that the dracorhodin-type compounds in its resin, confirmed by GC-MS and NMR, exert significant anti-inflammatory and hemostatic activity by inhibiting the NF-KB signaling pathway. This provides a scientific basis for the modernization of traditional Li ethnic medicine in Hainan. Furthermore, fusing ethnobotanical databases with multi-omics data can construct a 'metabolic fingerprint' of medicinal plants, achieving a leap from traditional empirical knowledge to precision pharmacology^[49].

Beyond medicinal plants, other ethnobotanical resources in Hainan also benefit from multi-omics approaches. Broussonetia papyrifera, the primary raw material for traditional Li bark cloth, has been a focus of genetic improvement^[6]. Whole-genome sequencing has identified CesA genes associated with fiber length, providing a basis for molecular breeding^[52], while metabolomic studies have demonstrated a correlation between phenolic compounds in B. papyrifera bark and its resistance to degradation, enhancing its durability^[53]. Similarly, Hainan's traditional upland rice (Shanlan rice), which has played a crucial role in ecological agriculture, was recorded as early as the Ming Dynasty^[30]. Genomic resequencing has identified DREB genes conferring drought resistance, offering valuable genetic resources for breeding stress-tolerant rice varieties^[54]. Moreover, population genetics studies have revealed gene introgression between Shanlan rice and wild rice, underscoring its retention of critical resistance traits during evolution^[55].

In the realm of food plants, Curcuma longa (turmeric) is widely used in traditional Li cuisine, particularly in yellow rice, known for its anti-inflammatory and digestive properties^[14]. Metabolomic analysis has quantified curcumin levels and validated its antioxidant activity^[14], while transcriptomic studies have uncovered regulatory mechanisms of curcumin biosynthesis under heat stress, providing insights for breeding heat-tolerant turmeric varieties^[56]. Additionally, Ficus spp. holds significant cultural symbolism in Li communities, particularly in fengshui forests, where it plays an essential ecological role. Recent metagenomic analyses have characterized nitrogen-fixing microbial communities in the aerial roots of Ficus, contributing to a deeper understanding of biological nitrogen fixation^[57]. Furthermore, ecological genomics, combined with GIS-based analysis, has confirmed the correlation between Ficus distribution patterns and village site selection, offering scientific support for sustainable land-use planning^[58]. Coconut is a crop of significant ethnobotanical importance to Hainan; multi-omics research was designed to address dwarfing and high-yield breeding needs. In a study on Cocos nucifera, 20 tall (traditional Li-grown) and 20 dwarf coconut varieties were selected, with three biological replicates per variety; samples included young leaves (for genomics/transcriptomics) and endosperm (for metabolomics), which were sampled at three developmental stages: one, three, and six months after pollination. Integrated multi-omics analysis revealed that altered gibberellin metabolism underlies the height differences between tall and dwarf coconuts, demonstrating convergent evolution in plant height selection across domesticated coconut species. The GA2ox gene, identified in this screen, has been adopted as a molecular marker for marker-assisted selection (MAS), shortening the breeding cycle of dwarf coconut from eight years to three years and increasing yield by 15% in pilot plantations^[59]. Moreover, the Palm Crop Database (MDB) serves as a valuable resource for ethnobotanical research by providing comprehensive genomic, metabolomic, and ecological datasets, thereby facilitating the conservation, genetic improvement, and medicinal compound exploration of traditional palm species in Hainan and beyond^[60].

Ethnobotanical plants in Hainan, particularly those used by indigenous communities such as the Li and Miao, present significant potential for biotechnological applications, including tissue culture and genetic transformation. Native ethnobotanical plant species, such as Horsfieldia hainanensis, have been identified as promising candidates for tissue culture-based propagation to support both in situ and ex situ conservation efforts^[61]. The tissue culture technology of Areca catechu has achieved positive results. An in vitro culture system has been successfully established using various explants, enabling asexual rapid propagation^[62]. As one of the most important ethnobotanical species in Hainan Province, the coconut holds great potential for the application of in vitro biotechnologies. The automation of coconut tissue culture, incorporating deep learning, temporary immersion systems, and other automated techniques, has significantly enhanced the efficiency of coconut in vitro propagation, providing innovative solutions for the rapid multiplication of elite coconut seedlings^[63−65]. The success of coconuts can also be replicated in other Hainan ethnobotanical plants. The use of these techniques on ethnobotanical species faces significant barriers. Key challenges include species-specific physiological responses that complicate protocol optimization, high contamination rates due to field-collected explants, and somaclonal variation that compromises genetic stability^[66]. Furthermore, limited infrastructure, technical expertise, and financial resources in local regions hinder large-scale implementation^[67]. A critical gap also exists in integrating traditional ethnopharmacological knowledge with standardized scientific methodologies, impeding the selection and authentication of suitable plant materials for culture^[30]. Examples illustrate the technical references and promoted development from research on other medicinal plants like ginseng and Fritillaria. For ginseng (Panax ginseng), multi-omics analyses, including transcriptomics and metabolomics, have revealed key mechanisms underlying phenotypic differences such as root morphology and ginsenoside accumulation, providing technical references for marker-assisted breeding and enhancing secondary metabolite yields through CRISPR-Cas9 editing, which promotes industrial scalability and sustainable cultivation^[68]. Similarly, for Fritillaria (e.g., Fritillaria cirrhosa), integrated multi-omics approaches have elucidated cadmium toxicity responses and alkaloid biosynthesis pathways under stress, offering insights into detoxification mechanisms and callus proliferation under different light qualities, thereby advancing propagation techniques and metabolite optimization for pharmaceutical applications^[69].

These new tools mentioned above enable the discovery of novel functional genes and bioactive compounds in traditionally utilized plant species, thus unlocking untapped resources for agriculture, medicine, and industry. Genomic analyses can unravel the evolutionary history and adaptive traits of ethnobotanical plants, providing insights into their resilience under climate change and guiding sustainable breeding strategies. Transcriptomic and metabolomic data further facilitate the identification of key regulatory networks underlying desirable traits (e.g., stress tolerance, secondary metabolite biosynthesis), supporting marker-assisted selection and precision breeding. Moreover, multi-omics approaches can assess the conservation status of endangered germplasm by quantifying genetic diversity and ecological interactions, ensuring the preservation of culturally and ecologically vital plant resources. In conclusion, multi-omics technologies, including genomics, metabolomics, and ecological genomics, offer a systematic and integrative approach to ethnobotanical research in Hainan, fostering the modernization of traditional medicinal and agricultural resources while contributing to global biodiversity conservation. Interdisciplinary collaborations between ethnobotanists, biotechnologists, and policymakers are essential to translate these insights into actionable strategies for climate-smart agriculture, bioprospecting, and the revitalization of indigenous knowledge systems. This framework not only bridges traditional practices with modern science but also paves the way for equitable and sustainable utilization of plant biodiversity.

The limitations of multi-omics include challenges in data integration due to a lack of standardized pre-processing, high computational demands requiring specialized bioinformatics expertise, potential biases from sample heterogeneity, and difficulties in functional validation of omics results, such as spatial resolution and causal inference in complex plant systems. Despite these, current progress in ethnic medicine in China emphasizes policy-driven integration of traditional knowledge with modern science, with advancements in protecting minority medicinal resources through expanded planting areas and innovations in drug development, though regional disparities persist^[69].

This study highlights Hainan Island's rich ethnobotanical heritage, shaped by its unique tropical biodiversity and the traditional knowledge of ethnic minorities like the Li and Miao, who utilize plants extensively in medicine, diet, and crafts. However, this knowledge faces threats from modernization and environmental changes. The research demonstrates that integrating traditional plant wisdom with multi-omics and biotechnologies offers solutions: it validates medicinal compounds, identifies adaptive traits, and supports conservation of endangered species. Ultimately, bridging indigenous knowledge with advanced biotechnologies is key to safeguarding Hainan's cultural and ecological diversity, fostering sustainable utilization of plant resources, and ensuring the longevity of this unique ethnobotanical legacy.