3rd Edition Of Plant Science and Molecular Biology World Conference 2026

Abstract

Cannabis sativa L. is a multifaceted botanical resource, encompassing robust fibers, nutritious seeds, and medically relevant phytocannabinoids such as tetrahydrocannabinol (THC) and cannabidiol (CBD). Light, a critical environmental factor, has been recognized as a pivotal modulator influencing biomass and cannabinoid yield, acting through a responsive photochemical apparatus. This study aims to elucidate the intricate relationship between escalating metabolic THC levels and photochemical efficiency in Cannabis. The investigation involved comprehensive analyses encompassing chlorophyll fluorescence kinetics, photosynthetic pigments, and immune-detection of photosynthetic machinery across seven Cannabis accessions originating from diverse environments. Concurrently, cannabinoid content assessment facilitated the categorization of accessions into three distinct groups based on their relative CBD and THC content. Our findings reveal a stoichiometrically negative correlation between THC content and key photochemical performance indicators, as assessed through OJIP kinetics. Notably, Zeaxanthin-dependent quenching emerged as a predominant contributor to reduced Non-Photochemical Quenching (NPQ) in Group III, characterized by elevated THC content (THC > 6%). Further validation through THC treatment in Arabidopsis thaliana corroborated a dose-dependent decline in photochemical efficiency, underscoring the exclusive role of THC in eliciting this response. Concurrently, the observed phenomenon damaged essential photosynthetic proteins, including D1, RbCL, and Lhc1 protein holo-complex, compromising overall plant health and yield. Furthermore, the study introduces a novel screening method for Cannabis based on cannabinoid content, offering practical insights into the intricate interplay between THC, photochemical efficiency, and the holistic health of the plant. These findings contribute to the broader understanding of Cannabis physiology and cultivation practices for optimized biomass and cannabinoid production.

Keywords: Cannabidiol, Cannabis sativa, Photochemical efficiency, Non-photochemical quenching, OJIP Kinetics