Tea is the second most consumed non-alcoholic beverage, only next to
water. However, its production and qualities, including rich flavors and
numerous health benefits, are often degraded by environmental stresses
and contaminations with various agrochemicals. While most of tea
quility-contributing secondary metabolites are synthesized in tea plant
leaves, such as catechins, caffeine, volatiles, saponins, and theanine,
primarily for defenses against biotic and abiotic stresses, few tea
garden management measures have employed this tea plant innate innumity
to enhance their tolerance against environmental stresses. This is
partly due to the limited understanding of the biosynthesis and
regulationof tea plant secondary metabolism. Given the importance of tea
plant secondary metabolites for both tea flavors, health functions, and
resistance against environmental stresses, study and in-depth
understanding of the biosynthesis and environmental regulation of tea
plant specialized metabolites are highly expected. Strategies developed
from these studies would promote the production of safe and high quality
teas. The review highlights relevant contexts of tea plant-environmental
interaction at the secondary metabolism interfaces, particular their
roles in enhancement of tea plant innate immunity and tea quality, so as
to guide future research on genetic improvement of tea plants for safer
food production and better human nutrition.