• Widely target metabolomics was used to identify the flavour profiles of matcha. • Differences in non-volatile and volatile metabolites metabolites of four varieties of matcha were revealed. • Aldehydes account for the most vital contribution in aroma quality formation of matcha.

Gray blight disease stands as one of the most destructive ailments affecting tea plants, causing significant damage and productivity losses. However, the dynamic roles of defense genes during the infection of gray blight disease remain largely unclear, particularly concerning their distinct responses in resistant and susceptible cultivars. In the pursuit of understanding the molecular interactions associated with gray blight disease in tea plants, a transcriptome analysis unveiled that 10,524, 17,863, and 15,178 genes exhibited differential expression in the resistant tea cultivar (Yingshuang), while 14,891, 14,733, and 12,184 genes showed differential expression in the susceptible tea cultivar (Longjing 43) at 8, 24, and 72 h post-inoculation (hpi), respectively. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses highlighted that the most up-regulated genes were mainly involved in secondary metabolism, photosynthesis, oxidative phosphorylation, and ribosome pathways. Furthermore, plant hormone signal transduction and flavonoid biosynthesis were specifically expressed in resistant and susceptible tea cultivars, respectively. These findings provide a more comprehensive understanding of the molecular mechanisms underlying tea plant immunity against gray blight disease.

Selenium (Se) is a trace element essential for human health. Incorporating Se into the tea ( Camellia sinensis (L.) O. Kuntze) cultivation has emerged as a cropping technology in the area of agriculture and food sciences. The production of Se-enriched tea is greatly influenced by Se bioavailability in tea garden soil, which in turn influences the Se assimilation, absorption, and transportation of tea plants. Recent studies reported that Se can regulate tea plant growth by altering soil microbes, thereby improving soil fertility and enhancing tolerance to abiotic stressors such as pesticide toxicity, fluoride toxicity, and temperature extremes. Selenium can modulate the secondary metabolism of tea and design Se-rich functional components, which determine the quality of Se-enriched tea. This review seeks to provide theoretical bases for optimizing Se management in tea gardens and the cultivation of Se-enriched tea.

Background: Roasting conditions significantly influence the sensory profile of Hubei strip-shaped green tea (HSSGT). Methods: This study examined the effects of roast processing on the sensory attributes, color qualities, physicochemical properties, and key aroma compounds of HSSGT. Sensory evaluation, color qualities determination, principal component analysis of physicochemical components (PCA), HS-SPME (headspace solid-phase microextraction) coupled with GC-MS (gas chromatography–mass spectrometry), relative odor activity value (ROAV), gas chromatography–olfactometry (GC-O), and absolute quantification analysis were employed to identify the critical difference in compounds that influence HSSGT desirability. Results: The results indicated that HSSGT roasted at 110 °C for 14 min achieved the highest sensory scores, superior physicochemical qualities, and an enhanced aroma index, which was attributed to shifting the proportion of chestnut to floral volatile compounds. Additionally, sensory-guided ROAV, GC-O, and absolute quantification revealed that linalool, octanal, nonanal, and hexanal were the most significant volatile compounds. The variations in these four critical compounds throughout the roasting process were further elucidated, showing that the ideal roasting conditions heightened floral aromas while diminishing the presence of less desirable green odors. These findings offer technical guidance and theoretical support for producing HSSGT with a more desirable balance of chestnut and floral aroma characteristics.

From the 1950s to the 1970s, approximately 80,000 kg of tea seeds were introduced from mainland China to the Xizang Autonomous Region for experimental cultivation. To assess the genetic diversity patterns of these tea accessions following more than half a century of acclimatization to plateau environments, we analyzed genetic variation, population structure, and genetic distinctiveness among fifty tea germplasm using nine phenotypic traits and 30 SSR markers. Phenotypic analysis revealed a moderately high level of genetic diversity, as indicated by the mean Shannon diversity index (H′ = 1.29). Principal component analysis (PCA) indicated that phenotypic variation was not geographically structured across the collection sites. The SSR markers exhibited a high degree of polymorphism, with an average polymorphic information content (PIC) of 0.610 and a genetic diversity index (I) of 1.437, indicating substantial genetic variation. Analysis of molecular variance (AMOVA) revealed that genetic differentiation occurred predominantly within populations, accounting for 91.49% of the total genetic variation. Similarly, 97.86% of the variation was attributed to differences within elevational gradients. Discriminant analysis of principal components (DAPC) and Bayesian population structure modeling (STRUCTURE) both identified two genetic clusters among the studied genotypes. Our results have practical implications for tea breeding programs by providing guidance for parental selection, informing germplasm collection management, and supporting the conservation of genetic resources.

The tea plant (Camellia sinensis (L.) O. Kuntze) is a globally important crop, yet its cultivation is continually challenged by a range of viral pathogens that can compromise plant health and product quality. In this study, eighteen symptomatic leaves were collected from the Hubei Province Tea Germplasm Resources Nursery, China, representing multiple cultivars and diverse genetic backgrounds. The samples were pooled into three groups and subjected to ribodepleted transcriptome sequencing. Analyses revealed a complex virome, with Tea plant necrotic ring blotch virus (TPNRBV) dominating Pools A and B, whereas Badnavirus betacolocalasiae was the most prevalent in Pool C. Functional enrichment of viral genes indicated involvement in multiple biological processes, including replication, host interaction, and metabolism. Notably, two previously uncharacterized viruses were identified: Tea plant-associated ourmia-like virus 1 (TeaOLV1) and Tea plant-associated rhabdo-like virus 1 (TeaRLV1). Phylogenetic reconstruction positioned TeaOLV1 within the Penoulivirus genus, while TeaRLV1 formed a distinct clade among plant-associated rhabdoviruses. Conserved motif analysis revealed typical viral domains, accompanied by lineage-specific variations in tea plants. Collectively, these findings enhance our understanding of the viral diversity in tea plants, provide refined taxonomic placement for newly identified viruses, and offer molecular insights into their evolutionary relationships and potential functional roles.