To characterize sensory differences among commercially available Chenxiang Tieguanyin with different labeled vintages and establish an objective discrimination method, Tieguanyin samples labeled from 5 to 40 years were analyzed using chemometrics and molecular sensory approaches. Amino acids and ester-type catechins decreased significantly with increasing labeled vintage, whereas theabrownin content increased steadily. Volatile profiles remained relatively stable between 10 and 25 years, while aroma characteristics gradually shifted from floral/fruity to aged, woody, and medicinal attributes, accompanied by enhanced mellowness and smoothness. A total of 22 key differential volatiles associated with labeled vintage were identified. Molecular docking and aroma recombination experiments were combined to systematically validate their contribution to the typical aged aroma of Tieguanyin. Among the machine-learning models, the convolutional neural network (CNN) exhibited the best classification performance, achieving 92.86% accuracy. This study provides an effective strategy for quality evaluation and labeled vintage discrimination of Chenxiang Tieguanyin.

Fujian Oolong Teas (FOTs) exhibit diverse aromas; however, a systematic understanding of the relationship between their volatiles and sensory attributes is lacking. This study developed a standardized aroma wheel for FOTs. By combining E-nose with quantitative descriptive analysis, the aroma profiles of 20 representative FOTs were classified into four groups: balanced, roasted, refreshing floral, and sweet floral. Innovative analytical ideas, including a combination of GC-MS profiling, PLS-DA, Generalized Linear Mixed Model, and rOAV analysis, identified 19 odorants responsible for this aroma diversity. Differences in the content and combination of compounds benzaldehyde, 2-pentylfuran, octanal, 2,2,6-trimethylcyclohexanone, phenylacetaldehyde, linalool, nonanal, methyl salicylate, decanal, hexyl 2-methylbutanoate, geraniol, indole, hexyl hexanoate, cis-3-hexenyl hexanoate, phenethyl isobutyrate, (E)-β-farnesene, β-ionone, α-farnesene, and (E)-nerolidol were found to be crucial in defining the distinct aromatic characteristics. Aroma recombination and omission experiments further confirmed the significance of these compounds. The findings provide a theoretical foundation for the quality control of FOTs.

The YABBY family of transcription factors plays an important role in plant growth, development, and stress tolerance. To further explore how CsYABBY family members participate in the drought response mechanism in tea plants (Camellia sinensis [L.] O. Kuntze), we performed a family analysis based on the published pan-genomes of 22 tea varieties and identified a total of 27 CsYABBYs, including 4 near-core genes. Collinearity analysis and Ka/Ks results showed that four near-core genes, CsYABBY7, CsYABBY9, CsYABBY10, and CsYABBY11, were relatively conserved and under purifying selection during tea domestication. In addition, expression patterns showed their differential responses to drought stress. Functional experiments further confirmed that overexpression of CsYABBY7/10/11 could reduce the accumulation of reactive oxygen species and increase the activities of osmoregulatory substances and antioxidant enzymes, thereby enhancing drought resistance. Inhibition of these genes has the opposite effect. CsYABBY9 exhibits dosage-sensitive regulation, in which both overexpression and knockdown compromise drought tolerance.

Drought stress is a serious natural challenge for tea plants that significantly affects tea yield and quality. miR171s play critical roles in plant stress responses, however, their role in drought stress tolerance in tea plants (Camellia sinensis) is poorly understood. This study experimentally verified the expression patterns of csn-miR171b-3p_2 and its target, scarecrow-like (SCL). We found that csn-miR171b-3p_2 could target and regulate CsSCL6-4 to play an important role in the defense against drought stress in tea plants. CsSCL6-4 is located in the nucleus and is self-activated in vivo. In addition, we obtained 819 putative binding regions of CsSCL6-4 using DNA affinity purification sequencing analysis, which were assigned to 786 different genes, four of which were drought-resistant genes (CsPrx, CsSDR, CsFAD7, and CsCER1). Yeast one-hybrid and dual-luciferase reporter assays revealed that CsSCL6-4 directly promoted the expression of these four drought resistance genes by binding motifs 1/2/3 in their promoter regions. Both overexpression and suppression of CsSCL6-4 proved that CsSCL6-4 participated in the defense against drought stress in tea plants by regulating the expression of CsPrx, CsSDR, CsFAD7, and CsCER1. In addition, suppression of csn-miR171b-3p_2 expression significantly increased the expression of CsSCL6-4 and activated CsSCL6-4-bound gene transcription under drought stress. Therefore, the csn-miR171b-3p_2-CsSCL6-4 module participates in tea plant resistance to drought stress by promoting the expression of drought resistance genes. Our results revealed the function of csn-miR171b-3p_2 in tea plants and provided new insights into the mechanism of tea plant resistance to drought stress.

High-altitude environments provide a favorable basis for tea quality formation, but suitable processing parameters for high-altitude Oolong Tea (HAOT, Camellia sinensis (L.) O. Kuntze) remain unclear. This study optimized key processing parameters for HAOT using a three-factor, three-level orthogonal design involving withering method, shaking intensity and standing time. Sensory evaluation, quantitative descriptive analysis (QDA), macro-compositions determination, headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC-MS), multivariate statistics and correlation analysis were used to clarify quality differences and their chemical basis. Leaf anatomical observation showed that high-altitude fresh leaves had a thicker cuticle and more compact mesophyll structure, suggesting the need for targeted processing regulation. Range analysis indicated that shaking intensity had the largest R value for sensory scores, followed by withering method, whereas standing time showed a comparatively small R value. The favorable combination was combined withering, heavy shaking (6 rounds) and 60 min standing, hereafter referred to as FHM. FHM showed the highest floral and fruity aroma scores and produced a mellow, full-bodied taste with a sweet aftertaste. It also contained significantly higher flavonoid and soluble sugar levels than the other processing combinations. A total of 65 volatile organic compounds were detected, with terpenoids and esters as the dominant classes. ROAV analysis identified geraniol, linalool, β-ionone, (E)-nerolidol and benzaldehyde as representative major aroma-active compounds, while geraniol and linalool were especially prominent in FHM. Correlation analysis further linked flavonoids and soluble sugars with positive taste attributes, and linalool and geraniol with floral–fruity aroma. These results provide a practical basis for optimizing HAOT processing and improving product quality.

During oolong tea production, the requirement for highly mature fresh leaves inevitably generates by-products. These include teas with coarse, loose shapes and a yellowish appearance, collectively known as "Huangpian" (HP). HP is usually discarded because of its weak flavor, which leads to a waste of resources and increased production cost of oolong tea. The objective of this study was to elevate the flavor of HP via optimized reprocessing methods. The results demonstrated that the taste thickness and aroma richness of the optimized HP (HP-O) were enhanced after 5 min of steam fumigation, 25 min of rolling, and 45 min of drying. Moreover, nonvolatile metabonomics and volatile metabonomics technologies were applied to explore the relevant mechanisms leading to improved HP quality. The improvement in taste was mainly related to flavonoid glycoside degradation and epigallocatechin isomerization, causing gallocatechin and flavonols to accumulate. A total of 19 metabolites were the potential key components contributing to the quality improvement of HP-O tea infusion. Additionally, alpha-ionone, (E, E)-2,4-decadienal, dehydrolinalool, and safranal may be the potential key volatiles to enhance the aroma of HP-O. This optimized reprocessing approach could provide a viable strategy for quality improvement of HP, thereby significantly improving the product's market acceptability.

The chemical basis of the sourness defect in aged Wuyi Rock Tea (WRT) and its mitigation by re-roasting remain unclear. Analysis of representative aged WRT identified a progressive pH decline as the primary physicochemical indicator of the defect. Integrated metabolomics and machine learning screened suberic acid, 3,4-dihydroxybenzoic acid, and vanillic acid as key markers, originating from lipid oxidative cleavage and catechin hydrolysis. Sensory reconstitution indicated that their combination reproduces the sour phenotype, a finding consistent with their high predicted affinity for the OTOP1 channel in molecular docking simulations. Crucially, re-roasting exhibited a stage-dependent regulatory pattern: it improves intermediate-aged tea, a process associated with the depletion of lipid-derived precursors, whereas it ameliorates fully aged tea likely through matrix-level sensory rebalancing. This latter mechanism potentially involves Maillard reaction products and polyphenol remodeling to modulate the sensory perception of acidity. These findings provide a theoretical foundation for WRT quality control.

The tender shoots of tea plant [Camellia sinensis (L.) Kuntze] contain characteristic flavor metabolites such as catechins, caffeine, and theanine, which are the raw materials for making various types of high-quality tea. The gene expression profiles with spatial information for tea shoots remain unclear, which has hindered the exploration of precise regulatory mechanisms of these characteristic metabolites in different cell types. Here, we provided a high-throughput analysis of the spatial gene expression of the tea shoot, including the apical bud, young leaf, and stem. The genome-wide expression pattern was delineated into nine representative spatial coexpression clusters, and cell type identification was achieved by integrating histological structures with marker gene annotation. The dynamic differentiation processes of cells in leaf and bud were revealed through the reconstruction of pseudotemporal trajectories, uncovering the coupling relationship between spatial organization and developmental progression. Gene Ontology enrichment analysis indicated that different clusters were enriched in functional pathways such as photosynthesis, cell wall construction, substance transport, and hormone response during differentiation, demonstrating their stage-specific expression throughout development. Additionally, we found that structural genes associated with the metabolism of catechins, theanine, and caffeine exhibited distinct spatial expression patterns across various tissues. Based on functional verification, we identified that the transcription factor gene CsTCP4 could positively regulate the biosynthesis of catechins and the hydrolysis of theanine. In conclusion, the spatial transcriptome atlas provides a foundational dataset for understanding gene expression heterogeneity in tea shoots and expands our understanding of the synergistic regulation of theanine and catechin metabolism in tea.

Abstract Tea plant germplasm in Fujian Province is characterized by substantial genetic diversity, yet the genetic basis of variation in volatile aroma compounds remains poorly understood. Here, we integrated whole-genome resequencing and volatile metabolomics for 466 tea plant accessions from Fujian Province to conduct population genetic and association analyses. The accessions formed seven genetic subgroups with marked divergence in genetic diversity, LD decay, and volatile composition, suggesting that genetic background contributes to aroma variation in tea. Using HS-SPME-GC–MS, we detected 105 volatile compounds, of which 29 showed high genetic contribution (H2 > 0.5). Metabolite-based GWAS identified multiple significant loci, including a stable peak on chromosome 7, pinpointing an AP2/ERF transcription factor gene, CsERF-like, as a prime candidate. CsERF-like localized to the nucleus, and functional assays showed that AsODN-mediated suppression reduced, whereas transient overexpression increased, free linalool accumulation in tea. Haplotype analysis further revealed promoter and coding variants associated with linalool content and distinct geographic distributions of alleles. Together, our results connect population-scale genetic variation in tea plant to linalool phenotypes in tea and provide functional evidence that CsERF-like positively regulates linalool accumulation, offering candidate loci for aroma improvement and marker-assisted breeding in tea plant.

Goji (Lycium barbarum L.) leaf tea (LBLT) has gained popularity among consumers owing to its pleasant aroma. Selecting optimal Goji cultivars for tea processing is critical for enhancing the quality of LBLT. This study investigated the aroma characteristics of Goji leaf white tea (LBLWT) and green tea (LBLGT) prepared from 25 Goji lines. LBLWT emitted woody, floral and fruity aromas, while LBLGT exhibited a distinct roasted corn aroma. The integrated application of variable importance in projection, odour activity value and partial least-squares regression analyses led to the identification of key aroma compounds, whose metabolic pathways were also illustrated. Using multi-criteria evaluation methods, excellent Goji lines suitable for processing LBLWT (Z20, Z48 and N1) and LBLGT (Z85, Z20, N1 and Z68) were screened. This study took the lead in adopting multi-criteria evaluation methods, screening high-quality Goji lines and providing theoretical basis for high-quality LBLT processing.

Epigallocatechin-3-O-gallate (EGCG) is an important ingredient that indicates tea quality and has healthcare functions. Magnesium nutrition can improve the quality and yield of tea plants, but its regulatory role in the biosynthesis of EGCG in tea plants has not been clarified. Herein, we performed a comprehensive analysis of the metabolomics and transcriptomics of the shoots of ‘Huangdan’ at five magnesium concentrations: L1-L5 (0, 0.15, 0.45, 0.6, and 0.9 mmol/L mg2+, respectively). The results showed that the EGCG content of tea shoots treated with low magnesium concentrations was higher compared to those treated with high magnesium concentrations. The contents of related metabolites such as p-coumaric acid and cyanide in the EGCG synthesis pathway increased in the L4 and L5 treatment groups, while those of dihydroquercetin, dinnamic acid, and epicatechin increased significantly in the L2 and L3 treatment groups. Under the influence of magnesium treatment, the biosynthesis of EGCG was affected by a series of structural genes: CsPAL (HD.01G0005520), HD.02G0024350), Cs4CL (HD.15G0008250, HD.13G0010220), CsDFR (HD.04G0026220), CsANS(HD.12G0016700) with CsaroDE (HD.03G0002480)-positive regulation, and CsPAL (HD.13G0009900, HD.06G0008610), CsC4H (HD.06G0017130), Cs4CL (HD.02G0027390, HD.04G0003270), CsCHS (HD.10G0022640), CsCHI (HD.01G0011100), CsF3′H (HD.15G0015490), CsF3′5′H (HD.13G0004300), CsANS (HD.07G0023630), and Csaro B (HD.01G0028400) with CsSCPL (HD.01G0041070)-negative regulation. Transcription factors MYB 44 and WRKY 17 may play a key role in EGCG biosynthesis, which is significantly induced by magnesium nutrition in tea tree shoots. This study elucidates the effect of magnesium nutrition on EGCG biosynthesis in tea plants and provides key candidate transcription factors to provide a reference for further research on high-EGCG tea varieties to improve tea quality.

One of the main factors constraining the growth of the tea business is the low use rate of summer tea. To enhance the utilization rate and improve the quality of summer tea, this study innovatively integrated shaking, freezing, and rolling into the traditional processing methods of white tea. Processing parameters were optimized through single-factor experiments combined with an L9(34) orthogonal experimental design. The quality of summer teas was systematically evaluated using sensory analysis, gas chromatography–mass spectrometry, and high-performance liquid chromatography. This study found that the optimal processing for summer tea was as follows: fresh leaves, room-temperature cold-air withering for 6.5 h, shaking at 10 rpm for 10 min, −20 °C freezing for 5 h, 25% strength rolling for 9 min, and drying at 75 °C for 2 h. The relative content of esterified catechins in summer tea produced by the optimal processing method was reduced by 14.62% compared with the control group. There were alterations in the content of amino acid components, with fresh and sweet amino acids increasing by 4.96% and 2.95%, respectively, and bitter amino acids reducing by 2.15%. Furthermore, γ-aminobutyric acid and L-theanine contents increased by 0.51% and 5.77%, respectively. Five characteristic volatile compounds were identified, namely, methyl salicylate, phenethyl formate, linalool, dimethyl sulfide, and isobutyraldehyde. The volatile profile was dominated by floral and fruity notes, except for dimethyl sulfide, which exhibited a distinct cooked corn-like aroma characteristic. This process was shown to improve the quality of summer tea. The results of this study provide a metabolite-level grounds for improving the quality of summer tea.

Oolong tea presents notable variations in taste profile and aroma characteristics under different cultivation conditions, particularly across altitudes. However, systematic investigations into the altitude-induced differences in key taste compounds and aroma composition remain limited. In this study, we examined six oolong tea cultivars, comparing their taste-related chemical constituents and aroma profiles under high- and low-altitude cultivation. Sensory evaluation, high-performance liquid chromatography (HPLC) and headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) were employed to characterize these differences. Sensory evaluation revealed that high-altitude oolong teas exhibited enhanced umami, sweetness, and floral intensity. In most cultivars, the levels of free amino acids, polyphenols, and soluble sugar were relatively higher under high-altitude conditions. HS-SPME-GC-MS identified 55 common volatile organic compounds (VOCs), with terpenes and esters comprising the largest number of compounds. Identification by partial least squares discriminant analysis (PLS-DA) combined with relative odor activity value (rOAV) screening yielded 22 candidate differential volatile organic compounds. Floral monoterpenes, including linalool, linalool oxide II and geraniol, were consistently higher in high-altitude teas, whereas most other volatiles varied primarily with cultivar rather than altitude. These chemical patterns are consistent with the sensory finding of stronger floral intensity in high-altitude samples. This study provides theoretical insights for cultivar selection and quality improvement of oolong tea grown in high-altitude regions.

Heat and drought are the stressors with significant adverse impacts on the yield stability of tea plants. The heat shock proteins 60 (HSP60s) play important roles in protecting plants under heat stress. However, the mechanism of HSP60s under heat and drought stresses remains unclear. Here, we identified 19 CsHSP60s (namely CsHSP60-1 to CsHSP60-19) in tea plants and classified them into three groups based on phylogenetic analysis. In addition, studies on gene duplication events during the evolutionary process demonstrated that CsHSP60 members were subjected to purify selection. Analysis of cis-acting elements revealed the presence of numerous stress and hormone-responsive elements within the promoter regions of CsHSP60s. Real-time quantitative fluorescent PCR (qRT-PCR) analyses demonstrated that CsHSP60s rapidly responded to heat and combined heat and drought stress while exhibiting a delayed response to drought stress. The inhibition of eight CsHSP60 genes via antisense oligodeoxynucleotide (AsODN) resulted in more severe damage and ROS accumulation. Specifically, CsHSP60-9, CsHSP60-16, and CsHSP60-19 exhibited notable reductions in Fv/Fm values and displayed increased accumulation of H2O2 and O2·-. These observations indicated a potential role for CsHSP60 in mitigating ROS accumulation under stress conditions, thereby enhancing tea plants' resilience to heat and drought stresses. Using a yeast two-hybrid (Y2H) assay, we identified that CsHSP60-2 and CsHSP60-16 physically interact with CsCPN10-4 and CsCPN10-5, respectively. These interactions suggest a cooperative chaperone activity between CsHSP60 and CsCPN10 in response to combined heat and drought stress. These findings lay a foundation for further understanding the involvement of HSP60s in the tolerance mechanisms to compound heat and drought stresses.

Rainy weather restricts the formation of high-quality Wuyi rock tea (WRT). Herein, an optimized withering process for rain-soaked leaves was developed using response surface methodology. Results showed that increasing the withering temperature, relative humidity, and withering time from 25 degrees C to 40 degrees C, 80 % to 97 %, and 3 to 6 h, respectively, effectively improved the sensory qualities of the optimized primary WRT (WRT-O) prepared from rain-soaked leaves compared with those before optimization. The high content of soluble sugars, L-theanine, catechins, esters, alcohols, terpenoids, ketones, aldehydes and aromatics contributed significantly to the formation of the unique flavor of WRT-O, which was significantly increased after optimizing the withering process. The flavor wheel of WRT-O was constructed, and its unique flavor was dominated by thickness and smoothness taste and floral, fruity, and sweet aroma. This study offers a theoretical reference for quality control of WRT produced from rain-soaked leaves.

The plant AT-rich sequence and zinc-binding protein (PLATZ) family is composed of plant-specific zinc finger-like transcription factors, which play important roles in plant growth, development, and stress tolerance. In this study, to gain a better understanding of the PLATZ gene in C. sinensis and elucidate its response under drought and high temperature conditions, the PLATZ gene family of the C. sinensis cultivar 'Tieguanyin' was systematically identified, and a total of 12 CsPLATZ family members were identified. Expasy online and other bioinformatics tools were used to analyze the members of the PLATZ gene family in terms of protein physicochemical properties, phylogenetic relationships, cis-acting elements, gene structures, and intra- and inter-species collinearity. The results of phylogenetic analysis classified the CsPLATZ family members into 2 subfamilies. The conserved domains and gene structures of PLATZ family members within the same subfamily had a high degree of consistency, whereas a certain degree of diversity was observed among the subfamilies. Twelve PLATZ genes were unevenly distributed across 7 chromosomes of C. sinensis and the promoter regions of these genes had multiple cis-acting elements related to hormone and stress responses. The collinearity analysis showed that there were 4 pairs of duplication events in the CsPLATZ gene family, all of which were segmental duplications. Based on this gene family, C. sinensis had a closer evolutionary relationship with A. thaliana than with O. sativa. The transcriptome analysis showed that the expression levels of CsPLATZ family members varied in different tissue samples of C. sinensis. 6 genes (CsPLATZ-1, CsPLATZ-2, CsPLATZ-3, CsPLATZ-4, CsPLATZ-6, and CsPLATZ-8) with high expression in shoots, young leaves, and roots were selected for high temperature and drought stress treatments, and their expression was quantified by qRT-PCR. The results indicated that the six genes might play important roles in the response to drought stress. In addition, CsPLATZ-2 and CsPLATZ-8 might have important functions in the response to high temperature stress. The results of this study will contribute to a better understanding of the biological functions of PLATZ genes and their possible roles in the growth, development, and stress responses of C. sinensis.

Oolong tea flavor is shaped by metabolite variations induced by season, processing, and cultivar. This study investigated the metabolic basis of sensory characteristics in Yongchun Foshou (YCFS) tea by integrating HS-SPME/GC-MS, HPLC, quantitative descriptive analysis (QDA), and chemometrics. Orthogonal partial least squares discriminant analysis (OPLS-DA) pinpointed key differential compounds between spring (YCFS-S) and autumn (YCFS-A) teas. Two-way ANOVA with effect size analysis confirmed that season was the dominant factor influencing most metabolites, although grade was the primary driver for free amino acids. YCFS-S contained significantly higher levels of taste-related phytochemical compounds, whereas YCFS-A exhibited elevated tea polyphenols. Statistical sensory analysis further identified a subset of key aroma compounds as drivers of seasonal and grade-based aroma differences. Correlation network analysis pinpointed 27 key sensory drivers: 12 aroma compounds defining a complex aroma profile dominated by floral and herbal notes, and 15 phytochemical compounds responsible for the umami, overall richness, and balanced bitterness. These findings were synthesized to construct the first dedicated flavor wheel for YCFS, elucidating how seasonality and grade collectively shape its flavor profile and providing a scientific basis for quality control and standardized production.

The plant AT-rich sequence and zinc-binding protein (PLATZ) family is composed of plant-specific zinc finger-like transcription factors, which play important roles in plant growth, development, and stress tolerance. In this study, to gain a better understanding of the PLATZ gene in C. sinensis and elucidate its response under drought and high temperature conditions, the PLATZ gene family of the C. sinensis cultivar 'Tieguanyin' was systematically identified, and a total of 12 CsPLATZ family members were identified. Expasy online and other bioinformatics tools were used to analyze the members of the PLATZ gene family in terms of protein physicochemical properties, phylogenetic relationships, cis-acting elements, gene structures, and intra- and inter-species collinearity. The results of phylogenetic analysis classified the CsPLATZ family members into 2 subfamilies. The conserved domains and gene structures of PLATZ family members within the same subfamily had a high degree of consistency, whereas a certain degree of diversity was observed among the subfamilies. Twelve PLATZ genes were unevenly distributed across 7 chromosomes of C. sinensis and the promoter regions of these genes had multiple cis-acting elements related to hormone and stress responses. The collinearity analysis showed that there were 4 pairs of duplication events in the CsPLATZ gene family, all of which were segmental duplications. Based on this gene family, C. sinensis had a closer evolutionary relationship with A. thaliana than with O. sativa. The transcriptome analysis showed that the expression levels of CsPLATZ family members varied in different tissue samples of C. sinensis. 6 genes (CsPLATZ-1, CsPLATZ-2, CsPLATZ-3, CsPLATZ-4, CsPLATZ-6, and CsPLATZ-8) with high expression in shoots, young leaves, and roots were selected for high temperature and drought stress treatments, and their expression was quantified by qRT-PCR. The results indicated that the six genes might play important roles in the response to drought stress. In addition, CsPLATZ-2 and CsPLATZ-8 might have important functions in the response to high temperature stress. The results of this study will contribute to a better understanding of the biological functions of PLATZ genes and their possible roles in the growth, development, and stress responses of C. sinensis.

Drought priming is a critical agronomic strategy for enhancing plant drought tolerance, yet the optimal priming intensity and transcriptional regulatory mechanisms underlying subsequent drought responses in the tea plant (Camellia sinensis) remain poorly characterised. In this study, we systematically evaluated tea plants exposed to recurrent drought stress under varying priming intensities. Results demonstrated that moderate drought priming specifically conferred superior drought tolerance compared to non-primed controls. Integrated metabolomic and transcriptomic profiling identified flavonoid biosynthesis as the key pathway associated with priming-induced drought resilience. Exogenous flavonoid application and overexpression of six biosynthesis genes (CsCHS, CsCHI, CsFLS, CsDFR, CsANS and CsANR) functionally validated flavonoids' role in drought adaptation. Notably, transcriptional regulators CsYABBY1 and CsMYB114 were identified as hub transcription factors demonstrating transcriptional activation potential towards flavonoid biosynthesis. Combinatorial transient overexpression and silencing assays revealed that both CsYABBY1 and CsMYB114 coordinately upregulate flavonoid biosynthesis genes, redirecting metabolic flux towards flavonoid accumulation to enhance drought tolerance. Multimodal validation through yeast one-hybrid assays, dual-luciferase reporter systems and electrophoretic mobility shift assays, as well as molecular docking, confirmed or simulated direct binding of CsYABBY1 and CsMYB114 to promoter regions of flavonoid biosynthesis genes for transcriptional activation. These findings establish a synergistic regulatory model where CsYABBY1 and CsMYB114 cooperatively enhance flavonoid accumulation through transcriptional reprogramming, thereby conferring acquired drought tolerance. This study provides mechanistic insights for developing adaptive cultivation practices and advances molecular breeding strategies for drought-resilient tea cultivars.

The sensory quality and metabolite profiles of the fresh and dried buds and leaves of Lycium from 26 cultivars(lines)were analyzed by sensory evaluation and metabolomics combined with multivariate statistical analysis.The results of sensory evaluation showed that the dried buds and leaves of Lycium had a mellow,fresh and sweet taste,and by liquid chromatography-mass spectrometry(LC-MS),879 metabolites were identified in Lycium buds and leaves,including amino acids and their derivatives,flavonoids,phenolic acids,saccharides,nucleotides and their derivatives,lignans and coumarins,alkaloids,terpenoids,organic acids,and lipids.Using partial least square discriminant analysis(PLS-DA)model and one-way analysis of variance(ANOVA),211 differential metabolites were selected,which were mainly enriched in the linoleic acid metabolism,flavonoid biosynthesis,flavonoids and flavanols biosynthesis,phenylpropanol biosynthesis,and galactose metabolism pathways.In addition,it was found that amino acids and their derivatives,flavonoids,sugars,and lipids were important components to discriminate the metabolites of different cultivars(lines).Partial least squares regression(PLSR)analysis showed that 26 metabolites including epicatechin,isoquercitrin,and rutin collectively affected the taste of Lycium tea such as mellow,thick,fresh,sweet and bitter.The results of sensory evaluation and PLSR analysis showed that seven cultivars(lines)of Lycium including'Ningqicai No.1','Ningqi No.9',Z90,Z68,Q3,Q6-13,and Z48 had better sensory quality and rich flavor substances.