Investigating Stress Tolerance and Genetics of Cannabis sativa HURV19Pan

Abstract

The cannabinoid synthesis pathway in Cannabis sativa involves a single major precursor molecule to all major cannabinoids, namely cannabigerolic acid (CBGA). CBGA is the key substrate for tetrahydrocannabinolic acid (THCAS), cannabidiolic acid (CBDAS) and cannabichromenic acid (CBCAS) synthases. Our research focuses on the Health Canada-approved strain HURV19Pan (HURV), the only known cultivar that accumulates significant levels of CBGA, but no detectable THCA or CBDA. We compared HURV's growth with a high-CBDA strain, BaOx, with a focus on quantifying plant morphology (height, stem width, chlorophyll) under stress and ideal conditions alongside physiology (light energy usage). Strains were measured to characterize differences potentially owing to cannabinoid content. DNA and RNA from each strain was PCR-analysed for the presence and expression of cannabinoid synthase genes. We discovered that high-CBGA HURV exhibits normal morphology, development, and photosynthetic capacity when compared to conventional cannabis strains. However, HURV lacks detectable expression of THCAS, CBDAS, and CBCAS. We demonstrate that HURV exhibits comparable stress response and typical growth to BaOx despite lacking downstream cannabinoid production. Our research into cannabis cultivation under ideal and suboptimal growth conditions (water-stress) aid to deepen our understanding of how cultivation affects different cannabis varieties.