Blue light extensively regulates multiple physiological processes and secondary metabolism of plants. Although blue light quantity (fluence rate) is important for plant life, few studies have focused on the effects of different blue light intensity on plant secondary metabolism regulation, including tea plants. Here, we performed transcriptomic and metabolomic analyses of young tea shoots (one bud and two leaves) under three levels of supplemental blue light, including low-intensity blue light (LBL, 50 μmol m^–2 s^–1), medium-intensity blue light (MBL, 100 μmol m^–2 s^–1), and high-intensity blue light (HBL, 200 μmol m^–2 s^–1). The total number of differentially expressed genes (DEGs) in LBL, MBL and HBL was 1, 7 and 1097, respectively, indicating that high-intensity blue light comprehensively affects the transcription of tea plants. These DEGs were primarily annotated to the pathways of photosynthesis, lipid metabolism and flavonoid synthesis. In addition, the most abundant transcription factor (TF) families in DEGs were bHLH and MYB, which have been shown to be widely involved in the regulation of plant flavonoids. The significantly changed metabolites that we detected contained 15 lipids and 6 flavonoid components. Further weighted gene co-expression network analysis (WGCNA) indicated that CsMYB (TEA001045) may be a hub gene for the regulation of lipid and flavonoid metabolism by blue light. Our results may help to establish a foundation for future research investigating the regulation of woody plants by blue light.

C-repeat binding factors (CBFs) are key signaling genes that can be rapidly induced by cold and bind to the C-repeat/dehydration-responsive motif (CRT/DRE) in the promoter region of the downstream cold-responsive (COR) genes, which play a vital role in the plant response to low temperature. However, the CBF family in tea plants has not yet been elucidated, and the possible target genes regulated by this family under low temperature are still unclear. In this study, we identified five CsCBF family genes in the tea plant genome and analyzed their phylogenetic tree, conserved domains and motifs, and cis-elements. These results indicate that CsCBF3 may be unique in the CsCBF family. This is further supported by our findings from the low-temperature treatment: all the CsCBF genes except CsCBF3 were significantly induced after treatment at 4 °C. The expression profiles of eight tea plant tissues showed that CsCBFs were mainly expressed in winter mature leaves, roots and fruits. Furthermore, 685 potential target genes were identified by transcriptome data and CRT/DRE element information. These target genes play a functional role under the low temperatures of winter through multiple pathways, including carbohydrate metabolism, lipid metabolism, cell wall modification, circadian rhythm, calcium signaling, transcriptional cascade, and hormone signaling pathways. Our findings will further the understanding of the stress regulatory network of CsCBFs in tea plants.

(1) Background: Although China is one of the largest tea-producing countries in the world, the Chinese tea industry is facing a decline in profits. However, an explosive market, namely milk tea, has garnered the attention of certain famous tea companies, several of which have launched milk tea products through sub-branding or co-branding. However, there is a scarce amount of literature on consumers’ attitudes toward these marketing strategies of the milk tea market. (2) Methods: Utilizing the choice experiment (CE) approach, the aim of this study was to explore consumer preferences for milk tea and investigate consumers’ socio-demographic characteristics regarding the preference for milk tea. (3) Results: Firstly, although consumers show positive attitudes toward tea bases that come from famous tea companies, they barely pay attention to the types of tea bases of milk tea products. As for ingredients, consumers show significantly negative attitudes toward non-dairy creamers when compared with fruit bases. Moreover, new brands could undermine consumers’ evaluations of milk tea. Secondly, education, the weekly frequency of drinking milk tea, and monthly allowance have a significant influence on consumer preferences. (4) Conclusions: Tea bases from famous tea companies can enhance consumer utility and promote consumer preference for milk tea. Thus, famous tea companies could seek cooperation with milk tea manufacturers, which would be a win–win strategy for both sides. On the other hand, tea companies should make use of their established reputations to gain consumers in the milk tea market, and co-branding or sub-branding strategies could be cost-effective methods to achieve this goal in the highly competitive milk tea market.