Antoszewski, Graham2024-03-132023https://hdl.handle.net/1813/114354Proper crop management requires rapid detection methods of abiotic and biotic stresses to ensure plant health and final product yield. Hemp (Cannabis sativa L.) is an emerging economically and environmentally sustainable crop, capable of yielding extensive biomass with low input. Nitrogen deficiency in hemp significantly reduces plant growth, affecting photosynthetic capacity and leading to a precipitous drop in overall biomass. A real-time, non- destructive detection method, such as Raman spectroscopy, is therefore critical to identify nitrogen deficiency in living hemp plant tissue for fast crop remediation. A two-part hydroponic experiment was conducted to investigate portable Raman spectroscopy as a viable hemp nitrogen deficiency detection method, and to compare the technique’s predictive ability against a hand- held SPAD chlorophyll meter. Raman scans show characteristic spectral markers indicating nitrogen deficiency corresponding to vibrational modes of carotenoids, an essential pigment for photosynthesis. Raman spectra and SPAD were used to train separate nitrogen deficiency discrimination models. Findings show a Raman-based model can consistently predict nitrogen within 4 days of deficiency treatment onset across trials, while SPAD could only differentiate nitrogen deficiency in the second trial when deficiency was more visible. Raman spectroscopy is capable of identifying nitrogen deficiency prior to visible symptoms in hemp. Implications of the research go beyond nitrogen deficiency – it bolsters the repertoire of plant stresses in which Raman spectroscopy provides non-invasive chemical information to hemp cultivators.en-USAttribution-NonCommercial-NoDerivatives 4.0 Internationaldissertation or thesis