Morphological analysis of glandular trichomes in six Cannabis sativa L. cultivars collected from the Rif Mountains (Northern Morocco)

Abstract

Cannabis sativa L. is a multipurpose crop with growing interest due to its medicinal properties and industrial applications. Trichomes specialized epidermal structures categorized as glandular or non-glandular play a crucial role in the biosynthesis of pharmacologically active compounds such as cannabinoids, terpenes, and flavonoids. Despite the global attention to C. sativa, Moroccan cultivars remain underexplored. This study investigates trichome morphology and density in six cultivars grown under controlled greenhouse conditions: ‘Beldiya’, ‘Mexicana’, ‘Khardala’, ‘Avocat’, ‘Critical Plus’, and ‘Industriel’. Bract samples were collected at maturity and analyzed using light microscopy. Thirty images per cultivar were examined to characterize trichome types and quantify their density. The results revealed significant inter-cultivar variation. ‘Mexicana’ exhibited the highest density of non-glandular trichomes (17%), while ‘Industriel’ showed the lowest (12%). Conversely, ‘Khardala’ and ‘Industriel’ recorded the highest proportions of glandular trichomes (88%). Principal component analysis effectively distinguished among cultivars based on trichome traits. Overall, both glandular and non-glandular trichomes were present across all cultivars, with ‘Beldiya’ and ‘Industriel’ showing lower trichome performance in terms of type and density. These findings highlight the morphological diversity among Moroccan cannabis cultivars and underscore the potential for further biochemical and agronomic characterization. ‘Khardala’ and ‘Mexicana’ show promising trichome traits and are recommended for further valorization, breeding, and phytochemical studies.