Responses of Secondary Metabolites and Transcriptomes in Tea Cultivar ‘Zhong Ming 6’ (Camellia Sinensis) under Blue Light and Red Light Journal Name: Plant Growth Regulation

Abstract Light is one of the most prestigious environmental sign, which stimulates plant metabolite consequences. Zhong Ming 6 (ZM6) is a green tea (Camellia sinensis) cultivar with highly accumulating TGGP. Here, three kinds of supplemental light wavelengths including blue light (BL,200 µmol m−2 s−1), red light(RL,200 µmol m−2 s−1), and White Light (WL/CK, 200 µmol m−2 s−1) were applied to explore their effects on the transcriptomes and metabolomics of young shoots (one bud and two leaves) in tea plants. Interestingly, artificial BL and RL significantly affect the secondary metabolites and transcriptome factors of tea plants. Here, BL extensively dominated the multiple physiological actions with secondary metabolism. In addition, RL could induce plant growth, development, and photosynthesis. Thoroughly, the identification of eight structural genes and 34 transcription factors (TFs) signiଁcantly correlated with total catechin (TC) and anthocyanin. Due to the upregulations of the CsGSTF1 gene in the flavonoid biosynthesis pathway, anthocyanin production was maximum under BL. Then, CsMYB75, bHLH-MYC, and other R2R3-MYBs were highly upregulated in BL to increase the accumulation of TC and anthocyanins in tea plants. Again, the CsMYB4 gene was highly significant and positively correlated with TC and anthocyanin accumulation under RL. We indicated that BL is more feasible due to the number of functional metabolites (gallic acid, caffeine, TC, TGGP (1, 2, 6-tri-O-galloyl-β-D-glucopyranose), and anthocyanin) being supreme. For taste, quality, and dynamic indigenous mechanism of the tea plant, RL is also suitable that increase Chlorophyll content and tea yield.