b'THE FROSTIER THE FLOWER, THE MORE POTENT THE CANNABISAdvanced microscopy reveals internal structures of cannabis biochemical factories. University of British ColumbiaCANNABIS FLOWERS WITHthe most mushroom-shaped hairs pack the biggest cannabinoid and fragrance punch, according to new research.While the cannabis leaf is iconic, its the chemicals produced by the tiny, frostlike hairs on cannabis flowers that give the plant its psychoactive and medicinal proper-ties and distinctive smell.In a study published in The Plant Journal, UBC researchers have revealed the unique structures and chemical outputs of the different types of hairs, or glan-dular trichomes, for the first time.Their findings confirm what many cannabis connois-seurs have long suspected: that the largest, mushroom-shaped stalked glandular trichomes are the richest source of THC- and CBD-forming metabolites and fragrance-giving terpenes.Despite its high economic value, our understanding of the biology of the cannabis plant is still in its infancy due to restricted legal access, said co-lead author Teagen Quilichini, a postdoctoral fellow at UBC botany and Anandia Laboratories Inc. Trichomes are the biochemical factories of the cannabis plant and this study is the foun- Multiphoton microscopy image of stalked glandular trichome.dation for understanding how they make and store theirCredit: Samuels Lab/UBCvaluable products.Previous research had identified three types of glan- As a result, Livingston explains, UV light could be dular trichomes based on their appearancebulbous,used to monitor trichome maturity on flowers and inform sessile and stalkedbut their relative contributions to theoptimal harvest times.chemical production of cannabis flowers were unknown. The researchers also conducted a gene expression analy-For this study, the UBC researchers used a combina- sis to investigate how instructions in trichome DNA are tion of advanced microscope techniques and chemicalconverted into the plants biochemical products. They found profiling to examine the internal structures and develop- that the stalked trichomes in Finola were strongly geared ment of individual trichomes in a fast-flowering hemptowards making cannabidiolic acid (CBDA) and terpenes.variety of Cannabis sativa called Finola. We found a treasure trove of genes that support the They found that under ultraviolet light, the stalkedproduction of cannabinoids and terpenes, said principal trichomes emitted a bright blue colour and contained ainvestigator Anne Lacey Samuels, a botany professor at large, distinctive pie-shaped disc of cells. The smaller ses- UBC. With further investigation, this could be used to sile trichomes, which do not have a stalk, emitted a redproduce desirable traits like more productive [cannabis] colour, had smaller secretory discs, and produced fewerstrains or strains with specific cannabinoid and terpene fragrant terpenes. profiles using molecular genetics and conventional breed-We saw that stalked glandular trichomes haveing techniques.expanded cellular factories to make more cannabi- Next, the researchers will investigate how trichomes noids and fragrant terpenes, said co-lead author Samexport and store the metabolites they produce.Livingston, a PhD candidate at UBC botany. We alsoTrichomes store the metabolites in their cell walls, found that they grow from sessile-like precursors andsaid Livingston. And whats really astounding is that such undergo a dramatic shift during development that can behigh levels of product should be toxic to the cells, so we visualized using new microscopy tools. want to understand how they manage this. 12GERMINATION.CA JANUARY 2020'