Full-length transcriptome and metabolism revealed the difference of callus formation of tea cutting under white, red and blue light.

Shen, Yaozong; Han, Xiao; Wang, Hui; Fan, Kai; Wang, Yu; Shen, Jiazhi; Li, He; Song, Dapeng; Ding, Shibo; Ding, Zhaotang

Short cutting is the main method of tea propagation. The callus formation at the base of cuttings has a certain absorption function. The early callus emergence is conducive to the resistance of cuttings to water and nutrient stress, thus promoting rooting and survival. In order to investigate the effect of light quality on the callus formation at the base of cuttings, this study used white (WL), red (660 nm, RL), and blue (430 nm, BL) light emitting diodes (LEDs) to treat tea cuttings. The results showed that compared with WL, BL promoted callus formation and RL inhibited callus formation. In order to explore the internal molecular mechanism of light quality affecting the difference of cutting callus formation, phytohormone determination and full-length transcriptome sequencing were conducted on mature leaves under different light quality treatments. The analysis of phytohormone showed that the contents of abscisic acid (ABA), indole-3-carboxylic acid (ICA), trans-zeatin (tZ), gibberellin 9 (GA9) and 5-deoxystrigol (5DS) were consistent with the callus formation trend, which showed BL > WL > RL. Full-length transcriptome sequencing was performed on mature leaves of cuttings under darkness (DL, CK), WL, RL and BL. Kyoto encyclopedia of genes and genomes (KEGG) analysis of genes, many genes participated in the "plant hormone signal transduction (ko04075)", such as auxin early response protein AUX/IAA, auxin response factor ARF, two-component response regulator B-ARR, and DELLA genes had highest expression under BL. Meanwhile, auxin synthesis and transport related genes were analyzed,, including L-tryptophan–pyruvate aminotransferase 1-like TAA1, flavin monooxygenase gene YUCCA, PIN1,3,4 and PIN-LIKES6 and 7, which also had the highest expression under BL. In conclusion, this study revealed the molecular mechanism of light quality regulating the callus formation of tea cutting, and provided new insights for the application of light quality in tea breeding.

Plant Growth Regulation, 2023, Vol 101, Issue 3, p715

0167-6903

Academic Journal

10.1007/s10725-023-01052-7