Monitoring of Cannabis Cultivar Technological Maturity by Trichome Morphology Analysis and HPLC Phytocannabinoid Content

Abstract

Objectives: This study aims at determining technological maturity (ten, seven, two days priorand at harvest day) through analyzing morphological changes of trichomes andphytocannabinoid content in samples from cultivated medical cannabis at three plot spots(southeast - SE, central - CN and northwest - NW) in greenhouse (with 3600 m 2). Materials andMethods: Soil-grown medical cannabis T-492 plant flowers were sampled within a ten days’timeline from three plot spots of 3600 m 2 greenhouse. Morphology analysis was performedusing Zeiss Stemi 508 stereomicroscope and phytocannabinoids content assessment wasperformed using German pharmacopoeial method for assay of cannabinoids. Results: HPLCanalysis revealed that total THC (%) in the samples was declining from SE (13.14%), all the waythrough CN (12.38%) to NW (9.14%) spot. Regarding timeline, total THC (%) was the highest inthe southeast location, starting with the highest levels on the tenth day before harvest(SE-10- 13.14%) and then decreasing on the seventh day prior to harvest (SE -7 -11.78%), on thesecond day prior harvest (SE -2-11.56%) and at the harvest day (SE h- 10.00%). The presence oftranslucent-milky, yellow-orange and dark brown trichome heads was observed. An incrementof the number of yellow-orange and dark brown colored capitate-stalked trichome heads wasconnected with cannabinoid content declining. Conclusion: This research gives directionsfor future conceptualization of correlational studies of cannabinoid content and changes intrichomes and purple coloration (probably from anthocyanins) in different Cannabis cultivars.