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

Objectives: This study aims at determining technological maturity (ten, seven, two days prior and at harvest day) through analyzing morphological changes of trichomes and phytocannabinoid content in samples from cultivated medical cannabis at three plot spots (southeast - SE, central - CN and northwest - NW) in greenhouse (with 3600 m2). Materials and Methods: Soil-grown medical cannabis T-492 plant flowers were sampled within a ten days’ timeline from three plot spots of 3600 m2 greenhouse. Morphology analysis was performed using Zeiss Stemi 508 stereomicroscope and phytocannabinoids content assessment was performed using German pharmacopoeial method for assay of cannabinoids. Results: HPLC analysis revealed that total THC (%) in the samples was declining from SE (13.14%), all the way through CN (12.38%) to NW (9.14%) spot. Regarding timeline, total THC (%) was the highest in the 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 the second day prior harvest (SE-2-11.56%) and at the harvest day (SEh- 10.00%). The presence of translucent-milky, yellow-orange and dark brown trichome heads was observed. An increment of the number of yellow-orange and dark brown colored capitate-stalked trichome heads was connected with cannabinoid content declining. Conclusion: This research gives directions for future conceptualization of correlational studies of cannabinoid content and changes in trichomes and purple coloration (probably from anthocyanins) in different Cannabis cultivars.