Molecular and Metabolic Changes under Environmental Stresses: The Biosynthesis of Quality Components in Preharvest Tea Shoots

Abstract

Severe environments impose various abiotic stresses on tea plants. Although much is known about the physiological and biochemical responses of tea (Camellia sinensis L.) shoots under environmental stresses, little is known about how these stresses impact the biosynthesis of quality components. This review summarizes and analyzes the changes in molecular and quality components in tea shoots subjected to major environmental stresses during the past 20 years, including light (shade, blue light, green light, and UV-B), drought, high/low temperature, CO2, and salinity. These studies reveal that carbon and nitrogen metabolism is critical to the downstream biosynthesis of quality components. Based on the molecular responses of tea plants to stresses, a series of artificial methods have been suggested to treat the pre-harvest tea plants that are exposed to inhospitable environments to improve the quality components in shoots. Furthermore, many pleiotropic genes that are up- or down-regulated under both single and concurrent stresses were analyzed as the most effective genes for regulating multi-resistance and quality components. These findings deepen our understanding of how environmental stresses affect the quality components of tea, providing novel insights into strategies for balancing plant resistance, growth, and quality components in field-based cultivation and for breeding plants using pleiotropic genes.

Discriminative Chemical Profiles of Shan Tuyet Tea (Camellia sinensis var. Shan) and Sinensis Tea (Camellia sinensis var. sinensis) Collected in Ta Xua, Son La, Vietnam and Their Correlation With Antioxidant Activity

“…Among tea phytochemicals, polyphenols (in particular, catechins) and amino acids have received immense attention as bioactive compounds and important primary metabolites in biosynthetic pathways of the featured compounds. 4,5 These compounds were thus considered as quality components for tea quality. 6 On the one hand, the major green tea catechins are epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG), and epigallocatechin gallate (EGCG).…”