ASHS 2024 Conference

Cannabis (Cannabis sativa L.) is cultivated for its cannabinoids, which have applications for therapeutic and recreational use. This phenomic evaluation explores accumulation of 16 cannabinoids of interest and associated morphological changes in Cannabis flowers. Eight cultivars of interest were grown in containers within an environmentally controlled greenhouse for 150 days (72 days reproductive). Light intensity, light duration, temperature, and relative humidity were regulated. Monitoring floral development, we observed a consistent increase in cannabinoid concentration as flowers matured, peaking in advanced stages of development. This accumulation pattern was consistent across diverse cultivars, which indicates this accumulation pattern to be the result of a fundamental biological mechanism. Concurrent with cannabinoid accumulation, we noted morphological changes in trichomes, which are widely utilized as markers of maturation within industry. Trichomes transitioned from sparse and translucent to abundant, enlarged, and displaying orange/amber hues as flowers matured, signifying floral maturation and trichome senescence. Importantly, a significant linear correlation emerged between cannabinoid accumulation and trichome morphological changes across all cultivars. This underscores a tight relationship between cannabinoid biosynthesis and trichome development, shaped by genetic factors. In summary, our findings demonstrate the intricate relationship between cannabinoid accumulation and floral morphology in Cannabis. Insights gained are invaluable for cultivar selection, breeding, and cultivation practices aimed at optimizing cannabinoid quantity and time to harvest. Understanding the underlying molecular mechanisms of cannabinoids promises tailored approaches for the optimization of cannabinoid production and the fostering of therapeutic and industrial advancements in Cannabis.