The Influence of Ultraviolet-A on Indicators of Plant Stress in Cannabis Sativa
The economic value of Cannabis sativa is influenced by inflorescence quality. Exposure to ultraviolet light (UV) has been shown to increase concentrations of Δ9-tetrahydrocannabinolic acid in drug-type plants. High doses of UV-B are physiologically damaging and this damage is theorized to be repaired photo-enzymatically, through exposure to white light or UV-A light. I assessed chlorophyll content, stomatal conductance, sexual lability, vegetative biomass, floral biomass, Δ9-tetrahydrocannabinol and cannabidiol content in C. sativa using light emitting diodes (LED) receiving 4h of UV-B alone or with 6h UV-A daily for five weeks. Significant (or interactive) effects of UV-A were not detected for any trait measured. However, plants exposed to UV-A+B showed a negative correlation between stomatal size and density, not seen under UV-B, suggesting UV-A impacts stomatal physiology. Results suggest a limited impact of UV-A exposure when white light is sufficient. Alternatively, further environmental variables may have obscured any effects from UV-A exposure. Keywords:
History
Language
engDegree
- Master of Science
Program
- Molecular Science
Granting Institution
Ryerson UniversityLAC Thesis Type
- Thesis