1 Introduction

Tea (Camellia sinensis) is one of the most widely consumed beverages globally, cherished for its unique flavor and numerous health benefits. The genetic diversity of tea plants is vast, owing to their prolonged cross-pollination nature, which has resulted in significant heritable variation (Kottawa-Arachchi et al., 2018). This diversity is crucial for breeding programs aimed at improving tea quality, yield, and stress tolerance. The high-quality genome sequence of the tea plant reveals that two rounds of whole-genome duplication events have influenced the expansion of gene families related to secondary metabolites and the production of quality compounds in tea, such as catechins, theanine, and caffeine. These gene expansions and transcriptional diversifications contribute to the unique flavor and health benefits of tea (Wei et al., 2018).

The collection and identification of tea germplasm resources are fundamental for the conservation and utilization of genetic diversity. These resources provide the raw material for breeding programs that aim to enhance tea's productivity, quality, and adaptability to various environmental conditions (Kottawa-Arachchi et al., 2018). Understanding the genetic relationships and diversity among tea cultivars can aid in the selection of parent plants for breeding, ensuring the development of superior tea varieties (Clarke et al., 2023). Moreover, the identification of specific gene families involved in the biosynthesis of key metabolites like catechins, theanine, and caffeine is essential for improving tea quality (Tai et al., 2018; Wei et al., 2018).

Recent studies have made significant strides in understanding the genetic and biochemical diversity of tea plants. For instance, high-quality genome assemblies of different tea varieties have provided insights into the evolutionary history and genetic basis of tea quality traits (Wei et al., 2018; Zhang et al., 2021). Population genomic analyses have revealed independent domestication events and extensive genetic introgressions, contributing to the genetic diversity of modern tea cultivars (Meegahakumbura et al., 2016; Zhang et al., 2021). However, there are still gaps in our knowledge, particularly regarding the genetic diversity of tea germplasm in under-researched regions like Uganda (Nalugo et al., 2022). Additionally, the role of the tea microbiome in promoting plant growth and enhancing tea quality remains an emerging field that requires further exploration (Bag et al., 2021).

This study explores the current status and progress in the collection, identification, and genetic diversity research of tea germplasm resources, providing scientific basis and guidance for future research and applications. By analyzing the genetic diversity of tea germplasm across different regions worldwide, the study summarizes the characteristics of genetic resource distribution, identification methods, and conservation status, while highlighting the existing gaps in research. It also discusses the achievements in genetic diversity research of tea plants through modern molecular marker technologies and bioinformatics tools, offering valuable references for the development of superior breeding materials and the conservation of rare germplasm resources. The study emphasizes the importance of tea germplasm conservation and utilization research in the context of global climate change and shifting market demands, and suggests directions and priorities for future research. This research will contribute to enhancing the management and utilization efficiency of tea germplasm resources, providing theoretical support and practical guidance for the sustainable development of the tea industry.

2 Collection of Tea Germplasm Resources

2.1 Classification and distribution of germplasm resources

Wild tea germplasm resources are primarily found in regions with rich biodiversity and favorable climatic conditions. For instance, Wuyishan (Mount Wuyi) in Southeast China is renowned for its diverse wild tea germplasm, which includes both black and oolong tea varieties. The genetic diversity in this region is significant, with high levels of observed and expected heterozygosity, indicating a rich genetic pool (Liu et al., 2022). Similarly, the ancient tea plant germplasm in Sandu County of Guizhou Province, China, exhibits high genetic and phenotypic diversity, making it a valuable resource for breeding new tea plant varieties (Zhao et al., 2021).

Cultivated tea germplasm includes a wide range of varieties developed through selective breeding and clonal selection. In Russia, the tea collection at the FRC SSC RAS includes locally derived cultivars and γ-irradiation mutants, which are adapted to extreme environmental conditions (Samarina et al., 2022). In China, the China National Germplasm Hangzhou Tea Repository preserves elite tea genetic resources, which are characterized by high genetic diversity and distinct genetic clusters (Chen et al., 2005). Additionally, the Biluochun tea plant populations in Dongting Mountain are known for their diverse agronomic traits and high breeding value (Lei et al., 2023).

2.2 Current status of germplasm collection domestically and internationally

In China, significant efforts have been made to collect and conserve tea germplasm. The Wuyishan region, for example, is a critical area for the conservation of tea germplasm due to its rich genetic diversity (Liu et al., 2022). Similarly, the tea germplasm in Sandu County of Guizhou Province is being actively managed to preserve its genetic and phenotypic diversity (Zhao et al., 2021). The China National Germplasm Hangzhou Tea Repository also plays a crucial role in preserving elite tea genetic resources (Chen et al., 2005).

Internationally, tea germplasm collections are being developed to adapt to diverse environmental conditions and enhance genetic diversity. In Russia, the FRC SSC RAS has established a tea collection that includes γ-irradiation mutants with larger genome sizes, which may improve adaptability to biotic and abiotic stress (Samarina et al., 2022). In Korea, the genetic diversity of tea germplasm is being assessed to ensure effective collection, conservation, and utilization (Lee et al., 2019). Additionally, the genetic diversity of tea germplasm in Ningde, China, is being studied to support breeding programs and conservation efforts (Zhu et al., 2023).

2.3 Strategies and methods for collecting tea germplasm resources

Ecological zoning is a critical strategy for collecting tea germplasm, as it ensures the representation of diverse environmental conditions. For instance, the tea germplasm collection in Wuyishan includes landraces with different genetic backgrounds, reflecting the ecological diversity of the region (Liu et al., 2022). Similarly, the tea germplasm in Sandu County is collected from various populations to capture the genetic and phenotypic diversity of the region (Zhao et al., 2021).

Genetic diversity is a key consideration in the collection of tea germplasm. In Russia, microsatellite markers are used to analyze the genetic diversity of tea germplasm, revealing distinct genetic clusters and significant genetic variation within clusters (Samarina et al., 2022). In China, RAPD markers are employed to evaluate the genetic diversity and relationships among elite tea genetic resources, facilitating the identification and conservation of diverse germplasm (Chen et al., 2005). Additionally, SNP markers are used to assess the genetic diversity of tea germplasm in Ningde, providing insights into the genetic relationships and conservation needs of the region (Zhu et al., 2023).

3 Identification of Tea Germplasm Resources

3.1 Indicators and methods for germplasm identification

Morphological identification of tea germplasm resources involves the assessment of various physical traits such as leaf shape, size, color, and flower morphology. These traits are essential for distinguishing between different tea cultivars and understanding their genetic diversity. For instance, leaf morphology, including parameters like leaf area and shape, has been used to identify and classify tea genotypes (Samarina et al., 2022; Cornea-Cipcigan et al., 2023). Additionally, flower organ morphology, such as petal color and structure, can provide valuable information for the identification of tea germplasm (Cornea-Cipcigan et al., 2023).

Molecular markers are crucial for the precise identification and characterization of tea germplasm. Techniques such as Simple Sequence Repeats (SSR), Random Amplified Polymorphic DNA (RAPD), and Single Nucleotide Polymorphisms (SNP) are commonly used. SSR markers are particularly effective in analyzing genetic diversity and population structure due to their high polymorphism and reproducibility (Lee et al., 2019; Hyun et al., 2020; Samarina et al., 2022). RAPD markers, although less specific, are useful for detecting genetic relationships and diversity among tea genotypes (Chen et al., 2005; Martono and Syafaruddin, 2018). SNP markers, identified through high-throughput sequencing technologies like ddRAD-seq, provide detailed genetic information and are valuable for understanding the genetic structure and breeding history of tea germplasm (Lin et al., 2019; Yamashita et al., 2019).

3.2 Morphological identification of tea germplasm resources

Leaf morphology is a primary indicator for the identification of tea germplasm. Parameters such as leaf size, shape, and color are measured and analyzed. Studies have shown a significant correlation between leaf area size and genome size, indicating that larger leaves may be associated with specific genetic traits (Samarina et al., 2022). The assessment of leaf morphology helps in distinguishing between different tea cultivars and understanding their adaptability to various environmental conditions. Studies have found that the spatiotemporal variations in leaf morphology of tea plants can be used to study plant responses to climate change, with larger leaves possibly being adapted to high precipitation and warmer climate conditions (Li et al., 2020).

Flower organ morphology, including petal color, shape, and structure, is another important aspect of morphological identification. Research indicates that two GLOBOSA-like MADS-box genes (CsGLO1 and CsGLO2) in tea plants are expressed in petals and stamens, playing a role in the regulation of petal morphology (Zhou et al., 2019). The color parameters of flowers, such as the CIELab values, can be used to differentiate between tea genotypes (Cornea-Cipcigan et al., 2023). These morphological traits are essential for the comprehensive characterization of tea germplasm and can provide insights into the genetic diversity and evolutionary history of tea plants.

3.3 Molecular marker identification of tea germplasm resources

SSR markers are widely used for the genetic analysis of tea germplasm due to their high polymorphism and reproducibility. They are effective in assessing genetic diversity, population structure, and relationships among tea genotypes. For example, SSR markers have been used to analyze the genetic diversity of tea accessions in Korea, revealing significant genetic variation within populations (Lee et al., 2019). Similarly, SSR markers have been applied to study the genetic structure of ancient tea plant germplasm in China, providing valuable data for conservation and breeding programs (Zhao et al., 2021).

SNP markers, identified through advanced sequencing technologies, offer high-resolution genetic information. They are useful for investigating the genetic background and breeding history of tea germplasm. For instance, Yamashita et al. (2019) analyzed the genetic structure of Japanese tea germplasm and landraces using ddRAD-seq technology, identifying over 10,000 SNP markers. The study revealed the genetic background and systematic structure of 167 tea samples, as well as the unique genetic background of the ‘Yabukita’ lineage, indicating that its genetic components are highly concentrated in Japanese tea breeding (Figure 1). Additionally, SNP markers have been employed to analyze the genetic diversity of oolong tea germplasm, aiding in the identification and selection of parent plants for breeding (Lin et al., 2019). 

4 Genetic Diversity Study of Tea Germplasm Resources

4.1 Overview of genetic diversity in tea germplasm resources

Genetic diversity is crucial for the adaptability and resilience of tea plants (Camellia sinensis) to various biotic and abiotic stresses. It provides a pool of genetic traits that can be utilized for breeding programs aimed at improving tea quality, yield, and resistance to diseases and environmental stresses. For instance, the study of tea germplasm in Wuyishan revealed significant genetic diversity, which is essential for the effective protection and utilization of these resources (Liu et al., 2022). Similarly, the genetic diversity of oolong tea germplasms has been shown to be vital for breeding and quality control (Lin et al., 2019).

Several factors influence the genetic diversity of tea germplasm, including geographical location, cultivation practices, and natural selection. For example, the genetic diversity of tea plants in Ningde and its adjacent regions is shaped by the interaction of local landraces with wild-type plants (Zhu et al., 2023). Additionally, human activities and environmental conditions can lead to genetic differentiation, as observed in the tea germplasm of Wuyishan, where population differentiation has occurred due to geographical isolation (Liu et al., 2022).

4.2 Research methods and techniques for genetic diversity

Phenotypic methods involve the assessment of observable traits such as leaf size, shape, and biochemical composition. For instance, the phenotypic diversity of ancient tea plant germplasm in Sandu County was evaluated using traditional methods, revealing high levels of diversity (Zhao et al., 2021). These methods are often complemented by molecular techniques to provide a comprehensive understanding of genetic diversity.

Genome-based techniques, such as the use of single nucleotide polymorphism (SNP) markers, simple sequence repeats (SSR), and amplified fragment length polymorphism (AFLP), are widely used to analyze genetic diversity. SNP markers were employed to study the genetic diversity of tea germplasm in Wuyishan and Ningde, providing insights into population structure and genetic relationships (Liu et al., 2022; Zhu et al., 2023). SSR markers have been used to assess the genetic diversity of tea germplasm in Korea and Russia, revealing significant molecular variability (Lee et al., 2019; Samarina et al., 2022). AFLP markers have also been utilized to distinguish between different tea cultivars in South India, highlighting the need for preserving genetic resources (Balasaravanan et al., 2003).

4.3 Research progress in genetic diversity of tea germplasm resources

Recent studies have made significant progress in analyzing the genetic diversity of various tea germplasms. For example, the genetic diversity of 137 tea germplasms from Wuyishan was analyzed using SNP markers, revealing rich genetic diversity and population differentiation (Liu et al., 2022). Similarly, the genetic diversity of 100 oolong tea landraces was assessed using high-throughput SNP technology, providing valuable information for breeding programs (Lin et al., 2019). In Russia, SSR markers were used to analyze the genetic diversity of tea germplasm, identifying distinct genetic clusters (Samarina et al., 2022).

Conservation efforts are crucial for maintaining the genetic diversity of tea germplasm. The development of core collections, such as the target-oriented core collection (TOCC) in tea germplasm, helps retain genetic diversity and various phytochemicals, facilitating effective utilization in breeding programs (Hyun et al., 2020). In Korea, the genetic diversity of tea germplasm has been assessed to inform conservation strategies, emphasizing the need for collecting new individuals to broaden genetic variation (Lee et al., 2019). Additionally, the identification of unique tea germplasms, such as the albino tea plant Menghai Huangye, highlights the importance of preserving special traits for future breeding efforts (Pang et al., 2021). The study of genetic diversity in tea germplasm resources is essential for the sustainable development and improvement of tea cultivation. Various research methods and techniques have been employed to analyze genetic diversity, and significant progress has been made in understanding and conserving these valuable resources.

5 Case Study

5.1 Research on the collection and identification of tea germplasm resources

The collection and identification of tea germplasm resources are crucial for conserving and utilizing the genetic diversity of tea plants. For instance, the Russian tea gene bank has collected representative tea germplasm resources from northern regions [Camellia sinensis (L.) O. Kuntze], including local varieties and radiation-induced mutants from the marginal germplasm banks located in Sochi and Maykop, Russia. These mutants often exhibit larger genome sizes and may have enhanced adaptability to biotic and abiotic stresses, providing potential genetic resources for tea cultivation in extreme environments. The study analyzed 43 mutants and clonally selected tea varieties using microsatellite (SSR) and start codon targeted (SCoT) markers, finding that SSR markers are more effective than SCoT markers in assessing the genetic diversity of polyploid tea germplasm resources. The results indicate that 106 genotypes in the Russian tea germplasm collection can be divided into three major genetic clusters (Figure 2). Despite the low genetic variation between clusters, the genotypes of tea cultivated in the northernmost regions show a greater genetic distance from those of the other two clusters, suggesting a unique genetic background. Additionally, the study revealed a significant moderate correlation between genome size and leaf area, providing important insights for the development of future tea germplasm conservation strategies and modern breeding programs (Samarina et al., 2022).

Another study in Korea collected 410 tea tree accessions. The research indicates that 85.4% (350 accessions) of the 410 tea tree germplasms were collected from Jeollanam-do, revealing relatively low genetic diversity and a simple population structure in Korean tea germplasm resources (Lee et al., 2019). The analysis of molecular variance (AMOVA) showed that most of the genetic variation (99%) exists within populations rather than among populations (1%), indicating that the genetic differentiation is mainly concentrated within populations (Table 1). This study provides a scientific basis for the effective collection, conservation, and utilization of tea germplasm resources. It also suggests that future tea breeding efforts should focus more on introducing and conserving diverse germplasm resources to enhance the genetic diversity and stress resistance of new varieties.

5.2 Case studies of genetic diversity study of tea germplasm resources

Understanding the genetic diversity of tea germplasm resources is crucial for the conservation of tea germplasm, the selection of superior cultivars, and the sustainable development of the tea industry. Wuyishan in China is a world-renowned tea-producing region, known for its rich tea germplasm resources and diverse tea varieties (Lin et al., 2019; Liu et al., 2022). Lin et al. (2019) conducted an in-depth analysis of the genetic diversity of tea germplasm resources in Wuyishan using SNP markers. The study selected 137 tea germplasm samples from Wuyishan and its surrounding areas and revealed the population structure and genetic diversity of these germplasm resources through high-throughput SNP genotyping. The results indicated that tea germplasm resources of Wuyishan possess high genetic diversity, with average values of genetic diversity indices (He and Ho) of 0.324 and 0.389, respectively, and a positive correlation between genetic differentiation (Fst values) and geographical distance. This suggests that significant genetic differentiation exists among tea germplasm in different geographical regions of Wuyishan. Cluster analysis and principal coordinate analysis (PCoA) further divided these tea germplasm resources into three main groups: Wuyishan, Southeastern Fujian, and Fujian wild germplasm groups (Figure 3). There was also some degree of population differentiation within tea germplasm of Wuyishan, reflecting genetic variation resulting from long-term tea cultivation and breeding in the region.

Another study in Ningde, China, analyzed the genetic diversity and population structure of 101 tea germplasm resources using SNP genotyping, highlighting the genetic differences between wild landraces and cultivated varieties (Zhu et al., 2023). Additionally, the genetic diversity of tea germplasm resources in the Russian gene bank was assessed using SSR and SCoT markers, identifying three distinct genetic clusters and significant genetic variation within clusters (Samarina et al., 2022). These studies provide support for the efficient management of tea germplasm resources and the development of breeding strategies.

6 Conservation and Utilization of Tea Germplasm Resources

6.1 Conservation strategies for tea germplasm resources

The conservation of tea germplasm resources is critical for maintaining genetic diversity and ensuring the sustainability of tea cultivation. Various strategies have been employed to conserve these valuable resources. For instance, the Russian genebank collection has utilized microsatellite markers to analyze genetic diversity, revealing distinct genetic clusters and significant genetic variation within clusters (Samarina et al., 2022). Similarly, the Korean genebank has focused on collecting and conserving new tea individuals to broaden genetic variation, as their study showed lower diversity and simpler population structure in Korean tea germplasms (Lee et al., 2019). Additionally, the conservation of ancient tea plant germplasm in Sandu County, China, has highlighted the importance of understanding genetic and phenotypic diversity to develop efficient management and breeding plans (Zhao et al., 2021). These efforts underscore the necessity of comprehensive conservation strategies, including the use of molecular markers, to preserve the genetic integrity of tea germplasm resources.

6.2 Innovative utilization and breeding application of germplasm resources

Innovative utilization and breeding applications of tea germplasm resources are pivotal for enhancing tea plant traits and ensuring the industry's growth. In Ningde, China, SNP genotyping has been employed to reveal the rich genetic diversity of tea germplasms, providing a molecular basis for breeding improvement (Zhu et al., 2023). The development of a target-oriented core collection (TOCC) based on phytochemical and molecular diversity has facilitated the effective utilization of tea germplasm in breeding programs (Hyun et al., 2020). Furthermore, the application of multi-omics approaches, including genomics and transcriptomics, has been proposed to advance tea plant breeding, focusing on high yield, quality, and resistance traits (Li et al., 2023). These innovative strategies highlight the potential of tea germplasm resources in breeding applications, promoting the development of superior tea cultivars.

6.3 Application prospects of germplasm resources in tea industry development

The application prospects of tea germplasm resources in the tea industry are vast, with significant potential for enhancing tea cultivation and production. The genetic diversity and adaptability of tea germplasms, such as those in the Russian genebank, can enable tea cultivation in extreme environmental conditions, expanding the global growing regions (Samarina et al., 2022). The identification of candidate genes associated with core agronomic traits in Biluochun tea plant populations can promote the development of molecular markers and the utilization of elite germplasm (Lei et al., 2023). Additionally, the rich genetic diversity of tea germplasms in Wuyishan provides a foundation for effective protection and utilization, optimizing tea cultivation (Liu et al., 2022). These prospects underscore the importance of leveraging tea germplasm resources to drive innovation and growth in the tea industry, ensuring its sustainability and competitiveness. By integrating conservation strategies, innovative utilization, and application prospects, the tea industry can harness the full potential of tea germplasm resources, fostering advancements in tea cultivation and production.

7 Challenges and Prospects in Tea Germplasm Resources Research

7.1 Current challenges in research

Research on tea germplasm resources faces several significant challenges. One of the primary issues is the limited genetic diversity within certain tea collections, which can hinder breeding programs aimed at improving tea plant traits. For instance, the genetic diversity of domestic tea accessions in Japan is limited compared to foreign accessions, necessitating the use of overseas genetic resources to expand breeding material diversity (Taniguchi, 2019). Additionally, the unclear genetic backgrounds of certain tea germplasms, such as those of oolong tea, pose biological limitations for breeding and quality control (Lin et al., 2019).

Another challenge is the impact of climate change on tea production. Climate change affects the prevalence and severity of biotic and abiotic stresses, which in turn impacts tea yield and quality. For example, fungal diseases are a significant biotic threat to tea plants, and their management is complicated by changing climate conditions (Pandey et al., 2021). Moreover, the high competition for agricultural land and urbanization activities in tea-growing countries further exacerbate the challenges faced by the tea industry (Arhin et al., 2022).

7.2 Future research directions and opportunities

Future research in tea germplasm resources should focus on several key areas to overcome current challenges and leverage new opportunities. One promising direction is the application of advanced genomic and biotechnological tools. Recent innovations in genomics, transcriptomics, and other multi-omics approaches have facilitated a deeper understanding of the molecular mechanisms underlying tea quality and the evolution of the tea plant genome (Xia et al., 2020; Li et al., 2023). These tools can be used to develop molecular markers for breeding, which can enhance the yield, quality, and resistance of tea plants (Li et al., 2023). Another important area is the conservation and utilization of genetic diversity. Efforts should be made to accurately characterize and preserve the genetic resources of tea plants, as seen in the comprehensive genetic diversity analyses conducted in regions like Ningde, China (Zhu et al., 2023). Additionally, the development of core collections and the use of genome analysis technology can help create new breeding materials and identify useful loci for important agricultural traits (Taniguchi, 2019).

Research should also address the challenges posed by climate change and biotic stresses. Developing and deploying resistant cultivars, along with adopting good cultural and agronomic practices, can mitigate the damage caused by fungal diseases and other stresses (Pandey et al., 2021; Huang et al., 2024). Furthermore, exploring the potential of organic tea production and sustainable farming practices can contribute to the long-term sustainability of the tea industry (Arhin et al., 2022).

7.3 Prospects for international cooperation in tea germplasm research

International cooperation is crucial for advancing tea germplasm research. Collaborative efforts can facilitate the exchange of genetic resources, knowledge, and technologies, which are essential for addressing global challenges in tea production. For example, Japan's active collection and preservation of tea genetic resources from 14 countries and regions highlight the importance of international collaboration in expanding genetic diversity and improving breeding programs (Taniguchi, 2019). Moreover, international cooperation can help standardize methodologies and share best practices for managing biotic and abiotic stresses. Joint research initiatives can focus on developing new disease management strategies and understanding the genetic variability of major fungal pathogens affecting tea plants (Pandey et al., 2021). Additionally, global efforts to promote sustainable farming practices and organic tea production can benefit from shared experiences and coordinated actions (Arhin et al., 2022).

Addressing the current challenges in tea germplasm resources research requires a multifaceted approach that leverages advanced biotechnological tools, conserves genetic diversity, and promotes international cooperation. By focusing on these areas, the tea industry can enhance its resilience and sustainability, ensuring the continued production of high-quality tea for future generations.

8 Concluding Remarks

The research on tea germplasm resources has revealed significant genetic diversity and variability across different regions and collections. For instance, the Russian genebank collection demonstrated that microsatellite markers (SSR) are effective in estimating genetic diversity despite the presence of polyploid tea accessions, identifying three distinct genetic clusters with greater genetic variation within clusters than between them. Similarly, the development of a target-oriented core collection (TOCC) in tea germplasm has shown high levels of molecular variability and phytochemical diversity, which are crucial for breeding programs. Studies using RAPD markers in Chinese elite tea genetic resources have also highlighted high genetic diversity and the practical utility of these markers for genetic identification . Furthermore, SNP markers have been employed to analyze the genetic diversity of tea germplasms in regions like Wuyishan and Ningde, revealing rich genetic backgrounds and significant intrapopulation variation. The genetic diversity of ancient tea plants in Sandu County and the tea germplasms in Korea and Guangxi Province have also been extensively studied, providing valuable baseline data for conservation and breeding efforts.

To further advance the research on tea germplasm resources, several key recommendations are proposed. Expanding the utilization of molecular markers, such as SNPs and SSRs, will enhance the resolution of genetic diversity studies and improve the accuracy of genetic relationship assessments. Increasing the collection and study of tea germplasms from underrepresented regions is crucial to achieving a more comprehensive understanding of global tea genetic diversity. Incorporating phytochemical analysis into genetic studies will help identify valuable traits for breeding programs and develop core collections that reflect both genetic and phytochemical diversity. Implementing effective conservation strategies based on genetic diversity data is necessary to protect endangered tea germplasms and ensure their sustainable use. The genetic information obtained from these studies should be applied to breeding programs focused on developing new tea cultivars with desirable traits, such as stress resistance, high yield, and improved quality.

The findings from these studies have significant implications for the tea industry. The identification of genetically diverse and phytochemically rich tea germplasms can lead to the development of new tea cultivars with improved quality, flavor, and stress resistance, thereby enhancing the competitiveness of the tea industry. The use of molecular markers for genetic identification and diversity analysis can streamline breeding programs, making them more efficient and targeted. Additionally, the conservation of ancient and region-specific tea germplasms ensures the preservation of unique genetic traits that could be crucial for future breeding efforts and adaptation to changing environmental conditions. Overall, these research efforts have contributed to the sustainable development and global expansion of the tea industry by providing a solid genetic foundation, offering reference and guidance for tea innovation and improvement.

Acknowledgments

We would like to express my heartfelt gratitude to my leader Mr. Huang who provided invaluable feedback during the review of the manuscript. We would also like to extend my sincere thanks to the two anonymous peer reviewers for their thorough evaluations and constructive comments, which have contributed to improving this manuscript. 

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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