New research from the University of British Columbia (UBC) published in The Plant Journal has shown that the quantity of trichomes on a cannabis plant determines its cannabinoid potency and fragrance.
Trichomes are tiny hairlike glands found on the leaves and flowers of the cannabis plant which produce terpenes, flavonoids, and cannabinoids such as delta-9 tetrahydrocannabinol (THC) and cannabidiol (CBD).
Using a combination of chemical profiling and advanced microscope techniques, UBC researchers examined the internal structures and development of trichomes in a quick-flowering hemp variety of Cannabis Sativa called Finola.
Researchers found that trichomes held the richest source of THC and CBD-forming metabolites and fragrant terpenes.
“We also found that [stalked trichomes] grow from sessile-like precursors and undergo a dramatic shift during development that can be visualized using new microscopy tools,” says study co-lead author Sam Livingston, Ph.D. “Trichomes store the metabolites in their cell walls. And what’s really astounding is that such high levels of product should be toxic to the cells, so we want to understand how they manage this.”
Researchers found that stalked trichomes emitted a bright blue color under an ultraviolet (UV) light and contained a large and distinctive pie-shaped disc of cells whereas smaller, stalk-less sessile trichomes emitted a red color, had smaller secretory discs, and produced fewer terpenes.
Livingston says that UV light could help researchers determine trichome maturity and indicate the best time to harvest.
Study co-lead author Teagen Quilichini says trichomes are biochemical factories for the cannabis plant and that the new study is foundational for understanding how they make and store their valuable products.
Quilichini notes that legal issues have hindered cannabis research in the past which made it illegal for people to marijuana as well as to conduct relevant clinical research on it.
Study authors say they are now planning to research how trichomes store and export CBD metabolites that they produce.