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Holweg MMSF, Kaiser E, Kappers IF, Heuvelink E, Marcelis LFM. The role of red and white light in optimizing growth and accumulation of plant specialized metabolites at two light intensities in medical cannabis ( Cannabis sativa L.). FRONTIERS IN PLANT SCIENCE 2024; 15:1393803. [PMID: 38957608 PMCID: PMC11217568 DOI: 10.3389/fpls.2024.1393803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Accepted: 05/20/2024] [Indexed: 07/04/2024]
Abstract
The cultivation of medical cannabis (Cannabis sativa L.) is expanding in controlled environments, driven by evolving governmental regulations for healthcare supply. Increasing inflorescence weight and plant specialized metabolite (PSM) concentrations is critical, alongside maintaining product consistency. Medical cannabis is grown under different spectra and photosynthetic photon flux densities (PPFD), the interaction between spectrum and PPFD on inflorescence weight and PSM attracts attention by both industrialists and scientists. Plants were grown in climate-controlled rooms without solar light, where four spectra were applied: two low-white spectra (7B-20G-73R/Narrow and 6B-19G-75R/2Peaks), and two high-white (15B-42G-43R/Narrow and 17B-40G-43R/Broad) spectra. The low-white spectra differed in red wavelength peaks (100% 660 nm, versus 50:50% of 640:660 nm), the high-white spectra differed in spectrum broadness. All four spectra were applied at 600 and 1200 μmol m-2 s-1. Irrespective of PPFD, white light with a dual red peak of 640 and 660 nm (6B-19G-75R/2Peaks) increased inflorescence weight, compared to white light with a single red peak of 660 nm (7B-20G-73R/Narrow) (tested at P = 0.1); this was associated with higher total plant dry matter production and a more open plant architecture, which likely enhanced light capture. At high PPFD, increasing white fraction and spectrum broadness (17B-40G-43R/Broad) produced similar inflorescence weights compared to white light with a dual red peak of 640 and 660 nm (6B-19G-75R/2Peaks). This was caused by an increase of both plant dry matter production and dry matter partitioning to the inflorescences. No spectrum or PPFD effects on cannabinoid concentrations were observed, although at high PPFD white light with a dual red peak of 640 and 660 nm (6B-19G-75R/2Peaks) increased terpenoid concentrations compared to the other spectra. At low PPFD, the combination of white light with 640 and 660 nm increased photosynthetic efficiency compared with white light with a single red peak of 660nm, indicating potential benefits in light use efficiency and promoting plant dry matter production. These results indicate that the interaction between spectrum and PPFD influences plant dry matter production. Dividing the light energy in the red waveband over both 640 and 660 nm equally shows potential in enhancing photosynthesis and plant dry matter production.
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Affiliation(s)
| | - Elias Kaiser
- Horticulture and Product Physiology, Wageningen University, Wageningen, Netherlands
| | - Iris F. Kappers
- Laboratory of Plant Physiology, Wageningen University, Wageningen, Netherlands
| | - Ep Heuvelink
- Horticulture and Product Physiology, Wageningen University, Wageningen, Netherlands
| | - Leo F. M. Marcelis
- Horticulture and Product Physiology, Wageningen University, Wageningen, Netherlands
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Contreras-Avilés W, Heuvelink E, Marcelis LFM, Kappers IF. Ménage à trois: light, terpenoids, and quality of plants. TRENDS IN PLANT SCIENCE 2024; 29:572-588. [PMID: 38494370 DOI: 10.1016/j.tplants.2024.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 02/16/2024] [Accepted: 02/20/2024] [Indexed: 03/19/2024]
Abstract
In controlled environment agriculture (CEA), light is used to impact terpenoid production and improve plant quality. In this review we discuss various aspects of light as important regulators of terpenoid production in different plant organs. Spectral quality primarily modifies terpenoid profiles, while intensity and photoperiod influence abundances. The central regulator of light signal transduction elongated hypocotyl 5 (HY5) controls transcriptional regulation of terpenoids under UV, red (R), and blue (B) light. The larger the fraction of R and green (G) light, the more beneficial the effect on monoterpenoid and sesquiterpenoid biosynthesis, and such an effect may depend on the presence of B light. A large fraction of R light is mostly detrimental to tetraterpenoid production. We conclude that light is a promising tool to steer terpenoid production and potentially tailor the quality of plants.
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Affiliation(s)
- Willy Contreras-Avilés
- Horticulture and Product Physiology, Plant Sciences Group, Wageningen University, P.O. Box 16, 6700, AA, Wageningen, The Netherlands; Plant Physiology, Plant Sciences Group, Wageningen University, P.O. Box 16, 6700, AA, Wageningen, The Netherlands
| | - Ep Heuvelink
- Horticulture and Product Physiology, Plant Sciences Group, Wageningen University, P.O. Box 16, 6700, AA, Wageningen, The Netherlands
| | - Leo F M Marcelis
- Horticulture and Product Physiology, Plant Sciences Group, Wageningen University, P.O. Box 16, 6700, AA, Wageningen, The Netherlands
| | - Iris F Kappers
- Plant Physiology, Plant Sciences Group, Wageningen University, P.O. Box 16, 6700, AA, Wageningen, The Netherlands.
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Bitežnik L, Štukelj R, Flajšman M. The Efficiency of CBD Production Using Grafted Cannabis sativa L. Plants Is Highly Dependent on the Type of Rootstock: A Study. PLANTS (BASEL, SWITZERLAND) 2024; 13:1117. [PMID: 38674526 PMCID: PMC11054458 DOI: 10.3390/plants13081117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 03/29/2024] [Accepted: 04/15/2024] [Indexed: 04/28/2024]
Abstract
The global cannabis market is continuously expanding and as a result, the cannabis industry demands new and improved agronomic cultivation practices to increase production efficiency of cannabidiol (CBD), which is valued for its therapeutic benefits. This study investigates the influence of three rootstock types on the survival rate, morphological parameters, and biochemical composition of cannabis: potentially dwarfing rootstocks (PDR), potentially vigorous rootstocks (PVR), and seedlings-as-rootstocks (SAR). Rootstocks were used for grafting two scion genotypes: 'ScionII' = chemotype II of industrial hemp, and 'ScionIII' = chemotype III of high CBD accumulating variety. Contrary to expectations, PVR and SAR did not outperform PDR on most of the measured variables. SAR showed the highest survival rate of the grafted cannabis plants (40-70%). The rootstock type had a statistically significant influence only on the bud compactness index in 'ScionII', with PDR being particularly noticeable. A comparative analysis of the 'rootstock/scion' combinations with their controls (non-grafted scions) revealed grafting's substantial improvement in most traits. Specifically, PDR increased CBD content by 27% in 'ScionIII', inflorescence yield and CBD yield per plant increased by 71% and 84%, respectively, when SAR was used in 'ScionII'. SAR showed to be the most effective rootstock type for CBD production. Our findings suggest grafting as a promising technique for optimizing cannabis's agronomic and medicinal potential, highlighting the necessity for further research on its underlying mechanisms to refine production efficiency and quality.
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Affiliation(s)
- Luka Bitežnik
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia;
| | - Roman Štukelj
- Research Institute, Faculty of Health Sciences, University of Ljubljana, Zdravstvena pot 5, SI-1000 Ljubljana, Slovenia;
| | - Marko Flajšman
- Department of Agronomy, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia;
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Westmoreland FM, Kusuma P, Bugbee B. Elevated UV photon fluxes minimally affected cannabinoid concentration in a high-CBD cultivar. FRONTIERS IN PLANT SCIENCE 2023; 14:1220585. [PMID: 37636099 PMCID: PMC10452874 DOI: 10.3389/fpls.2023.1220585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 07/18/2023] [Indexed: 08/29/2023]
Abstract
Ultraviolet photons (UV) can damage critical biochemical processes. Plants synthesize photo-protective pigments that absorb UV to minimize damage. Cannabinoids absorb UV, so increased UV has the potential to increase cannabinoid synthesis. Studies in the 1980's provided some evidence for this hypothesis in low-cannabinoid cultivars, but recent studies did not find an increase in cannabinoid synthesis with increasing UV in high-cannabinoid cultivars. These studies used low UV photon fluxes, so we examined the effect of higher UV photon fluxes. We used fluorescent UV lights with 55% UV-B (280 to 314 nm) and 45% UV-A (315 to 399 nm). Treatments began three weeks after the start of short days and continued for five weeks until harvest. Established weighting factors were used to calculate the daily biologically effective UV photon flux (UV-PFDBE; 280 to 399 nm). Daily UV-PFDBE levels were 0, 0.02, 0.05, and 0.11 mol m-2 d-1 with a background daily light integral (DLI) of 30 mol m-2 d-1. This provided a ratio of daily UV-PFDBE to DLI of 41 to 218% of summer sunlight in the field. Cannabinoid concentration was 3 to 13% higher than the control in UV treated plants, but the effect was not statistically significant. Fv/Fm and flower yield were reduced only in the highest UV treatment. These data support recent literature and lead us to conclude that an elevated flux of UV photons is not an effective approach to increase cannabinoid concentration in high-cannabinoid cultivars.
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Affiliation(s)
- F. Mitchell Westmoreland
- Department of Plants, Soils and Climate, Crop Physiology Laboratory, Utah State University, Logan, UT, United States
| | - Paul Kusuma
- Department of Plants, Soils and Climate, Crop Physiology Laboratory, Utah State University, Logan, UT, United States
- Department of Plant Sciences, Horticulture and Product Physiology, Wageningen University & Research, Wageningen, Netherlands
| | - Bruce Bugbee
- Department of Plants, Soils and Climate, Crop Physiology Laboratory, Utah State University, Logan, UT, United States
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Tanney CAS, Lyu D, Schwinghamer T, Geitmann A, Ruan ED, Smith DL. Sub-optimal nutrient regime coupled with Bacillus and Pseudomonas sp. inoculation influences trichome density and cannabinoid profiles in drug-type Cannabis sativa. FRONTIERS IN PLANT SCIENCE 2023; 14:1131346. [PMID: 37275248 PMCID: PMC10236210 DOI: 10.3389/fpls.2023.1131346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Accepted: 04/06/2023] [Indexed: 06/07/2023]
Abstract
Cannabis sativa remains under heavy legal restriction around the globe that prevents extensive investigations into agricultural applications for improving its development. This work investigates the potential of specific plant growth-promoting rhizobacteria (PGPR) to improve Cannabis cannabinoid yield through increased trichome densities on floral organs, and to determine if sub-optimal environmental conditions would affect the outcomes of PGPR presence by altering plant development and cannabinoid profiles. Here, Pseudomonas sp. or Bacillus sp. were applied to the root system either separately or in a consortium to determine the effect of this bacterial treatment on the density of stalked glandular trichomes. Further, a low nutrient regime was applied for the first half of plant development to determine if an environmental stressor interacts with the effects of the microbial treatments on stalked trichome densities. Following 8 weeks of flower development, trichome density on calyces and bracts of inflorescences were determined using microscopy. Our findings unexpectedly indicate that recommended nutrient levels were linked to a decreasing trend in trichome densities with PGPR inoculations, but a low nutrient regime coupled with PGPR treatment increased them. Cannabinoid content is partially consistent with these results, in that a low nutrient regime increased the abundance of key cannabinoids compared to recommended regimes, with Bacillus sp. inoculation linked to the greatest number of significant changes between the two nutrient regimes. Overall, this work provides insight into how PGPR presence affects Cannabis stalked trichome development and cannabinoid profiles, and how environmental stressors can affect, and even enhance, trichome densities and influence major cannabinoid production, thereby pointing towards avenues for reducing the reliance on synthetic fertilizers during plant production without compromising yield.
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Affiliation(s)
- Cailun A. S. Tanney
- Department of Plant Science, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
| | - Dongmei Lyu
- Department of Plant Science, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
| | - Timothy Schwinghamer
- Lethbridge Research and Development Centre, Agriculture and Agri-food Canada, Lethbridge, AB, Canada
| | - Anja Geitmann
- Department of Plant Science, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
| | - Eric D. Ruan
- School of Chemistry and Chemical Engineering, Sichuan Institute of Arts and Science, Dazhou, Sichuan, China
| | - Donald L. Smith
- Department of Plant Science, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
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Westmoreland FM, Bugbee B. Sustainable Cannabis Nutrition: Elevated root-zone phosphorus significantly increases leachate P and does not improve yield or quality. FRONTIERS IN PLANT SCIENCE 2022; 13:1015652. [PMID: 36483962 PMCID: PMC9724152 DOI: 10.3389/fpls.2022.1015652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 10/17/2022] [Indexed: 06/17/2023]
Abstract
Phosphorus (P) is an essential but often over-applied nutrient in agricultural systems. Because of its detrimental environmental effects, P fertilization is well studied in crop production. Controlled environment agriculture allows for precise control of root-zone P and has the potential to improve sustainability over field agriculture. Medical Cannabis is uniquely cultivated for the unfertilized female inflorescence and mineral nutrition can affect the yield and chemical composition of these flowers. P typically accumulates in seeds, but its partitioning in unfertilized Cannabis flowers is not well studied. Here we report the effect of increasing P (25, 50, and 75 mg P per L) in continuous liquid fertilizer on flower yield, cannabinoid concentration, leachate P, nutrient partitioning, and phosphorus use efficiency (PUE) of a high-CBD Cannabis variety. There was no significant effect of P concentration on flower yield or cannabinoid concentration, but there were significant differences in leachate P, nutrient partitioning, and PUE. Leachate P increased 12-fold in response to the 3-fold increase in P input. The P concentration in the unfertilized flowers increased to more than 1%, but this did not increase yield or quality. The fraction of P in the flowers increased from 25 to 65% and PUE increased from 31 to 80% as the as the P input decreased from 75 to 25 mg per L. Avoiding excessive P fertilization can decrease the environmental impact of Cannabis cultivation.
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Morello V, Brousseau VD, Wu N, Wu BS, MacPherson S, Lefsrud M. Light Quality Impacts Vertical Growth Rate, Phytochemical Yield and Cannabinoid Production Efficiency in Cannabis sativa. PLANTS (BASEL, SWITZERLAND) 2022; 11:2982. [PMID: 36365435 PMCID: PMC9659141 DOI: 10.3390/plants11212982] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 10/17/2022] [Accepted: 10/19/2022] [Indexed: 06/16/2023]
Abstract
Light is one of the most crucial parameters for enclosed cannabis (Cannabis sativa) production, as it highly influences growth, secondary metabolite production, and operational costs. The objective of this study was to investigate and evaluate the impact of six light spectra on C. sativa ('Babbas Erkle Cookies' accession) growth traits and secondary metabolite (cannabinoid and terpene) profiles. The light spectra evaluated included blue (430 nm), red (630 nm), rose (430 + 630 nm, ratio 1:10), purple (430 + 630 nm, ratio 2:1), and amber (595 nm) LED treatments, in addition to a high-pressure sodium (HPS, amber-rich light) treatment as a control. All the LED light treatments had lower fresh mean inflorescence mass than the control (HPS, 133.59 g plant-1), and monochromatic blue light yielded the least fresh inflorescence mass (76.39 g plant-1). Measurement of Δ9-tetrahydrocannabinol (THC) concentration (%) and total yield (g plant-1) showed how inflorescence mass and THC concentration need to be analyzed conjointly. Blue treatment resulted in the highest THC concentration (10.17% m/m), yet the lowest THC concentration per plant (1.44 g plant-1). The highest THC concentration per plant was achieved with HPS (2.54 g plant-1). As with THC, blue light increased cannabigerol (CBG) and terpene concentration. Conversely, blue light had a lesser impact on cannabidiol (CBD) biosynthesis in this C. sativa chemotype. As the combined effects of the light spectrum on both growth traits and secondary metabolites have important ramifications for the industry, the inappropriate spectral design could cause a reduction in cannabinoid production (20-40%). These findings show promise in helping producers choose spectral designs that meet specific C. sativa production goals.
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Affiliation(s)
| | | | | | | | | | - Mark Lefsrud
- Department of Bioresource Engineering, McGill University, 21111 Lakeshore Road, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada
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Reichel P, Munz S, Hartung J, Kotiranta S, Graeff-Hönninger S. Impacts of Different Light Spectra on CBD, CBDA and Terpene Concentrations in Relation to the Flower Positions of Different Cannabis Sativa L. Strains. PLANTS (BASEL, SWITZERLAND) 2022; 11:2695. [PMID: 36297719 PMCID: PMC9612076 DOI: 10.3390/plants11202695] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Revised: 09/30/2022] [Accepted: 10/10/2022] [Indexed: 06/16/2023]
Abstract
Cannabis is one of the oldest cultivated plants, but plant breeding and cultivation are restricted by country-specific regulations. The plant has gained interest due to its medically important secondary metabolites, cannabinoids and terpenes. Besides biotic and abiotic stress factors, secondary metabolism can be manipulated by changing light quality and intensity. In this study, three morphologically different cannabis strains were grown in a greenhouse experiment under three different light spectra with three real light repetitions. The chosen light sources were as follows: a CHD Agro 400 ceramic metal-halide lamp with a sun-like broad spectrum and an R:FR ratio of 2.8, and two LED lamps, a Solray (SOL) and an AP67, with R:FR ratios of 13.49 and 4, respectively. The results of the study indicated that the considered light spectra significantly influenced CBDA and terpene concentrations in the plants. In addition to the different light spectra, the distributions of secondary metabolites were influenced by flower positions. The distributions varied between strains and indicated interactions between morphology and the chosen light spectra. Thus, the results demonstrate that secondary metabolism can be artificially manipulated by the choice of light spectrum, illuminant and intensity. Furthermore, the data imply that, besides the cannabis strain selected, flower position can have an impact on the medicinal potencies and concentrations of secondary metabolites.
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Affiliation(s)
- Philipp Reichel
- Agronomy, Institute of Crop Science, University of Hohenheim, 70599 Stuttgart, Germany
| | - Sebastian Munz
- Agronomy, Institute of Crop Science, University of Hohenheim, 70599 Stuttgart, Germany
| | - Jens Hartung
- Biostatistics, Institute of Crop Science, University of Hohenheim, 70599 Stuttgart, Germany
| | - Stiina Kotiranta
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, P.O. Box 27, FI-00014 Helsinki, Finland
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Islam MJ, Ryu BR, Rahman MH, Rana MS, Cheong EJ, Wang MH, Lim JD, Hossain MA, Lim YS. Cannabinoid accumulation in hemp depends on ROS generation and interlinked with morpho-physiological acclimation and plasticity under indoor LED environment. FRONTIERS IN PLANT SCIENCE 2022; 13:984410. [PMID: 36340385 PMCID: PMC9634648 DOI: 10.3389/fpls.2022.984410] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
Manipulation of growth and development of cannabis (Cannabis sativa L.) has received considerable interest by the scientific community due to its high value in medicinal and recreational use worldwide. This study was conducted to investigate the effects of LED spectral changes on reactive oxygen species (ROS) and cannabinoid accumulation by provoking growth, pigmentation, photosynthesis, and secondary metabolites production of cannabis grown in an indoor environment. After three weeks of vegetative growth under greenhouse condition, plants were further grown for 90 days in a plant factory treated with 4 LED light compositions with a canopy-level photosynthetic photon flux density (PPFD) of 300 µmol m-2 s-1 for 16 h. Photosynthetic pigments and photosynthetic rate were linearly increased up to 60 days and then sharply decreased which was found most prominent in L3: MB 240 (Red 85% + Blue 15%) and L4: PF 240 (Red 70% + Blue 30%) LED light compositions. A high concentration of H2O2 was also observed in L3 and L4 treatments which provoked lipid peroxidation in later growth stage. In addition, higher accumulation of cannabinoid was observed under L4 treatment in most cases. It is also evident that higher ROS created a cellular stress in plant as indicated by higher osmolyte synthesis and enzyme activity which initiate quick maturation along with higher cannabinoids accumulation in cannabis plant. Therefore, it can be concluded that ROS metabolism has a crucial role in morpho-physiological acclimation and cannabinoid accumulation in hemp plants. The findings of this study provide further insight on the use of LED light to maximize the production of cannabinoid.
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Affiliation(s)
- Md Jahirul Islam
- Department of Bio-Health Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, South Korea
- Physiology and Sugar Chemistry Division, Bangladesh Sugarcrop Research Institute, Pabna, Bangladesh
| | - Byeong Ryeol Ryu
- Department of Bio-Health Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, South Korea
| | - Md Hafizur Rahman
- Department of Bio-Health Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, South Korea
| | - Md Soyel Rana
- Department of Bio-Health Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, South Korea
| | - Eun Ju Cheong
- Division of Forest Science, College of Forest and Environmental Sciences, Kangwon National University, Chuncheon, South Korea
| | - Myeong-Hyeon Wang
- Department of Bio-Health Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, South Korea
| | - Jung-Dae Lim
- Department of Bio-Health Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, South Korea
- Department of Herbal Medicine Resource, Kangwon National University, Samcheok, South Korea
| | - Mohammad Anwar Hossain
- Department of Genetics and Plant Breeding, Bangladesh Agricultural University, Mymensingh, Bangladesh
| | - Young-Seok Lim
- Department of Bio-Health Convergence, College of Biomedical Science, Kangwon National University, Chuncheon, South Korea
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Danziger N, Bernstein N. Too Dense or Not Too Dense: Higher Planting Density Reduces Cannabinoid Uniformity but Increases Yield/Area in Drug-Type Medical Cannabis. FRONTIERS IN PLANT SCIENCE 2022; 13:713481. [PMID: 36247643 PMCID: PMC9559401 DOI: 10.3389/fpls.2022.713481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Accepted: 06/15/2022] [Indexed: 06/16/2023]
Abstract
A major challenge for utilizing cannabis for modern medicine is the spatial variability of cannabinoids in the plant, which entail differences in medical potency. Since secondary metabolism is affected by environmental conditions, a key trigger for the variability in secondary metabolites throughout the plant is variation in local micro-climates. We have, therefore, hypothesized that plant density, which is well-known to alter micro-climate in the canopy, affects spatial standardization, and concentrations of cannabinoids in cannabis plants. Canopy density is affected by shoot architecture and by plant spacing, and we have therefore evaluated the interplay between plant architecture and plant density on the standardization of the cannabinoid profile in the plant. Four plant architecture modulation treatments were employed on a drug-type medicinal cannabis cultivar, under a density of 1 or 2 plants/m2. The plants were cultivated in a naturally lit greenhouse with photoperiodic light supplementation. Analysis of cannabinoid concentrations at five locations throughout the plant was used to evaluate treatment effects on chemical uniformity. The results revealed an effect of plant density on cannabinoid standardization, as well as an interaction between plant density and plant architecture on the standardization of cannabinoids, thus supporting the hypothesis. Increasing planting density from 1 to 2 plants/m2 reduced inflorescence yield/plant, but increased yield quantity per area by 28-44% in most plant architecture treatments. The chemical response to plant density and architecture modulation was cannabinoid-specific. Concentrations of cannabinoids in axillary inflorescences from the bottom of the plants were up to 90% lower than in the apical inflorescence at the top of the plant, considerably reducing plant uniformity. Concentrations of all detected cannabinoids in these inflorescences were lower at the higher density plants; however, cannabinoid yield per cultivation area was not affected by neither architecture nor density treatments. Cannabigerolic acid (CBGA) was the cannabinoid least affected by spatial location in the plant. The morpho-physiological response of the plants to high density involved enhanced leaf drying at the bottom of the plants, increased plant elongation, and reduced cannabinoid concentrations, suggesting an involvement of chronic light deprivation at the bottom of the plants. Therefore, most importantly, under high density growth, architectural modulating treatments that facilitate increased light penetration to the bottom of the plant such as "Defoliation", or that eliminated inflorescences development at the bottom of the plant such as removal of branches from the lower parts of the plant, increased chemical standardization. This study revealed the importance of plant density and architecture for chemical quality and standardization in drug-type medical cannabis.
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Harpaz D, Bernstein N, Namdar D, Eltzov E. Portable biosensors for rapid on-site determination of cannabinoids in cannabis, a review. Biotechnol Adv 2022; 61:108031. [PMID: 36058440 DOI: 10.1016/j.biotechadv.2022.108031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 08/12/2022] [Accepted: 08/26/2022] [Indexed: 11/02/2022]
Abstract
Recent studies highlight the therapeutic virtues of cannabidiol (CBD). Furthermore, due to their molecular enriched profiles, cannabis inflorescences are biologically superior to a single cannabinoid for the treatment of various health conditions. Thus, there is flourishing demand for Cannabis sativa varieties containing high levels of CBD. Additionally, legal regulations around the world restrict the cultivation and consumption of tetrahydrocannabinol (THC)-rich cannabis plants for their psychotropic effects. Therefore, the use of cannabis varieties that are high in CBD is permitted as long as their THC content does not exceed a low threshold of 0.3%-0.5%, depending on the jurisdiction. These chemovars are legally termed 'hemp'. This controlled cannabinoid requirement highlights the need to detect low levels of THC, already in the field. In this review, cannabis profiling and the existing methods used for the detection of cannabinoids are firstly evaluated. Then, selected valuable biosensor technologies are discussed, which suggest portable, rapid, sensitive, reproducible, and reliable methods for on-site identification of cannabinoids levels, mainly THC. Recent cutting-edge techniques of promising potential usage for both cannabis and hemp analysis are identified, as part of the future cultivation and agricultural improvement of this crop.
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Affiliation(s)
- Dorin Harpaz
- Institute of Postharvest and Food Science, Department of Postharvest Science, Volcani Institute, Agricultural Research Organization, Rishon LeZion 7505101, Israel; Institute of Biochemistry, Food Science and Nutrition, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
| | - Nirit Bernstein
- Institute of Soil Water and Environmental Sciences, Volcani Institute, Agricultural Research Organization, POBox 6, Bet-Dagan 50250, Israel.
| | - Dvora Namdar
- Institute of Soil Water and Environmental Sciences, Volcani Institute, Agricultural Research Organization, POBox 6, Bet-Dagan 50250, Israel.
| | - Evgeni Eltzov
- Institute of Postharvest and Food Science, Department of Postharvest Science, Volcani Institute, Agricultural Research Organization, Rishon LeZion 7505101, Israel.
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Larsen DH, Li H, Shrestha S, Verdonk JC, Nicole CCS, Marcelis LFM, Woltering EJ. Lack of Blue Light Regulation of Antioxidants and Chilling Tolerance in Basil. FRONTIERS IN PLANT SCIENCE 2022; 13:852654. [PMID: 35463427 PMCID: PMC9021895 DOI: 10.3389/fpls.2022.852654] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
Blue light, measuring from 400 to 500 nm, is generally assumed to increase the content of antioxidants in plants independent of the species. Blue light stimulates the biosynthesis of phenolic compounds such as flavonoids and their subclass anthocyanins from the phenylpropanoid pathway. Flavonoids, anthocyanins, and phenolic acids are strong reactive oxygen species (ROS) scavengers and may lessen the symptoms of abiotic stresses such as chilling. We tested the hypothesis that a high percentage of blue light induces the accumulation of antioxidants and that this effect depends on the photosynthetic photon flux density (PPFD, 400-700 nm). The effect may be more pronounced at a lower PPFD. We investigated the changes in primary and secondary metabolites of basil in response to the percentage of blue light (9, 33, 65, and 100%) applied either as a 5-day End-Of-Production (EOP) treatment or continuous throughout the growth cycle in the green cv. Dolly. We also studied if the response to the percentage of blue light (9 or 90%) was dependent on the total PPFD (100 or 300 μmol m-2 s-1 PPFD) when applied as a 5-day EOP treatment in the green cv. Dolly and the purple cv. Rosie. For both green and purple basil, it was found that the percentage of blue light had little effect on the levels of antioxidants (rosmarinic acid, total ascorbic acid, total flavonoids, and total anthocyanins) at harvest and no interactive effect with PPFD was found. Antioxidants generally decreased during postharvest storage, wherein the decrease was more pronounced at 4 than at 12°C. Chilling injury, as judged from a decrease in F v /F m values and from the occurrence of black necrotic areas, was not affected by the percentage of blue light. Particularly, chilling tolerance in the purple cultivar was increased in plants grown under higher PPFD. This may be related to the increased levels of soluble sugar and starch in leaves from high PPFD treated plants.
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Affiliation(s)
- Dorthe H. Larsen
- Horticulture and Product Physiology Group, Wageningen University and Research, Wageningen, Netherlands
| | - Hua Li
- Horticulture and Product Physiology Group, Wageningen University and Research, Wageningen, Netherlands
| | - Samikshya Shrestha
- Horticulture and Product Physiology Group, Wageningen University and Research, Wageningen, Netherlands
| | - Julian C. Verdonk
- Horticulture and Product Physiology Group, Wageningen University and Research, Wageningen, Netherlands
| | | | - Leo F. M. Marcelis
- Horticulture and Product Physiology Group, Wageningen University and Research, Wageningen, Netherlands
| | - Ernst J. Woltering
- Horticulture and Product Physiology Group, Wageningen University and Research, Wageningen, Netherlands
- Food and Biobased Research, Wageningen University and Research, Wageningen, Netherlands
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Crispim Massuela D, Hartung J, Munz S, Erpenbach F, Graeff-Hönninger S. Impact of Harvest Time and Pruning Technique on Total CBD Concentration and Yield of Medicinal Cannabis. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11010140. [PMID: 35009146 PMCID: PMC8747189 DOI: 10.3390/plants11010140] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 12/18/2021] [Accepted: 12/31/2021] [Indexed: 05/19/2023]
Abstract
The definition of optimum harvest and pruning interventions are important factors varying inflorescence yield and cannabinoid composition. This study investigated the impact of (i) harvest time (HT) and (ii) pruning techniques (PT) on plant biomass accumulation, CBD and CBDA-concentrations and total CBD yield of a chemotype III medical cannabis genotype under indoor cultivation. The experiment consisted of four HTs between 5 and 11 weeks of flowering and three PTs-apical cut (T); removal of side shoots (L) and control (C), not pruned plants. Results showed that inflorescence dry weight increased continuously, while the total CBD concentration did not differ significantly over time. For the studied genotype, optimum harvest time defined by highest total CBD yield was found at 9 weeks of flowering. Total CBD-concentration of inflorescences in different fractions of the plant's height was significantly higher in the top (9.9%) in comparison with mid (8.2%) and low (7.7%) fractions. The T plants produced significantly higher dry weight of inflorescences and leaves than L and C. Total CBD yield of inflorescences for PTs were significantly different among pruned groups, but do not differ from the control group. However, a trend for higher yields was observed (T > C > L).
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Affiliation(s)
- Danilo Crispim Massuela
- Cropping Systems and Modelling, Institute of Crop Science, University of Hohenheim, 70599 Stuttgart, Germany; (S.M.); (F.E.); (S.G.-H.)
- Correspondence: ; Tel.: +49-711-459-23066
| | - Jens Hartung
- Biostatistics, Institute of Crop Science, University of Hohenheim, 70599 Stuttgart, Germany;
| | - Sebastian Munz
- Cropping Systems and Modelling, Institute of Crop Science, University of Hohenheim, 70599 Stuttgart, Germany; (S.M.); (F.E.); (S.G.-H.)
| | - Federico Erpenbach
- Cropping Systems and Modelling, Institute of Crop Science, University of Hohenheim, 70599 Stuttgart, Germany; (S.M.); (F.E.); (S.G.-H.)
| | - Simone Graeff-Hönninger
- Cropping Systems and Modelling, Institute of Crop Science, University of Hohenheim, 70599 Stuttgart, Germany; (S.M.); (F.E.); (S.G.-H.)
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Saloner A, Bernstein N. Nitrogen Source Matters: High NH 4/NO 3 Ratio Reduces Cannabinoids, Terpenoids, and Yield in Medical Cannabis. FRONTIERS IN PLANT SCIENCE 2022; 13:830224. [PMID: 35720524 PMCID: PMC9198551 DOI: 10.3389/fpls.2022.830224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 03/31/2022] [Indexed: 05/11/2023]
Abstract
The N form supplied to the plant, ammonium (NH4 +) or nitrate (NO3 -), is a major factor determining the impact of N nutrition on plant function and metabolic responses. We have hypothesized that the ratio of NH4/NO3 supplied to cannabis plants affects the physiological function and the biosynthesis of cannabinoids and terpenoids, which are major factors in the cannabis industry. To evaluate the hypothesis we examined the impact of five supply ratios of NH4/NO3 (0, 10, 30, 50, and 100% N-NH4 +, under a uniform level of 200 mg L-1 N) on plant response. The plants were grown in pots, under controlled environment conditions. The results revealed high sensitivity of cannabinoid and terpenoid concentrations and plant function to NH4/NO3 ratio, thus supporting the hypothesis. The increase in NH4 supply generally caused an adverse response: Secondary metabolite production, inflorescence yield, plant height, inflorescence length, transpiration and photosynthesis rates, stomatal conductance, and chlorophyll content, were highest under NO3 nutrition when no NH4 was supplied. Ratios of 10-30% NH4 did not substantially impair secondary metabolism and plant function, but produced smaller inflorescences and lower inflorescence yield compared with only NO3 nutrition. Under a level of 50% NH4, the plants demonstrated toxicity symptoms, which appeared only at late stages of plant maturation, and 100% NH4 induced substantial plant damage, resulting in plant death. This study demonstrates a dramatic impact of N form on cannabis plant function and production, with a 46% decrease in inflorescence yield with the increase in NH4 supply from 0 to 50%. Yet, moderate levels of 10-30% NH4 are suitable for medical cannabis cultivation, as they do not damage plant function and show only little adverse influence on yield and cannabinoid production. Higher NH4/NO3 ratios, containing above 30% NH4, are not recommended since they increase the potential for a severe and fatal NH4 toxicity damage.
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Affiliation(s)
- Avia Saloner
- Institute of Soil, Water and Environmental Sciences, Volcani Center, Rishon LeTsiyon, Israel
- The Robert H. Smith Faculty of Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Nirit Bernstein
- Institute of Soil, Water and Environmental Sciences, Volcani Center, Rishon LeTsiyon, Israel
- *Correspondence: Nirit Bernstein,
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Rodriguez-Morrison V, Llewellyn D, Zheng Y. Cannabis Inflorescence Yield and Cannabinoid Concentration Are Not Increased With Exposure to Short-Wavelength Ultraviolet-B Radiation. FRONTIERS IN PLANT SCIENCE 2021; 12:725078. [PMID: 34795683 PMCID: PMC8593374 DOI: 10.3389/fpls.2021.725078] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 10/13/2021] [Indexed: 05/25/2023]
Abstract
Before ultraviolet (UV) radiation can be used as a horticultural management tool in commercial Cannabis sativa (cannabis) production, the effects of UV on cannabis should be vetted scientifically. In this study we investigated the effects of UV exposure level on photosynthesis, growth, inflorescence yield, and secondary metabolite composition of two indoor-grown cannabis cultivars: 'Low Tide' (LT) and 'Breaking Wave' (BW). After growing vegetatively for 2 weeks under a canopy-level photosynthetic photon flux density (PPFD) of ≈225 μmol⋅m-2⋅s-1 in an 18-h light/6-h dark photoperiod, plants were grown for 9 weeks in a 12-h light/12-h dark "flowering" photoperiod under a canopy-level PPFD of ≈400 μmol⋅m-2⋅s-1. Supplemental UV radiation was provided daily for 3.5 h at UV photon flux densities ranging from 0.01 to 0.8 μmol⋅m-2⋅s-1 provided by light-emitting diodes (LEDs) with a peak wavelength of 287 nm (i.e., biologically-effective UV doses of 0.16 to 13 kJ⋅m-2⋅d-1). The severity of UV-induced morphology (e.g., whole-plant size and leaf size reductions, leaf malformations, and stigma browning) and physiology (e.g., reduced leaf photosynthetic rate and reduced Fv/Fm) symptoms intensified as UV exposure level increased. While the proportion of the total dry inflorescence yield that was derived from apical tissues decreased in both cultivars with increasing UV exposure level, total dry inflorescence yield only decreased in LT. The total equivalent Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD) concentrations also decreased in LT inflorescences with increasing UV exposure level. While the total terpene content in inflorescences decreased with increasing UV exposure level in both cultivars, the relative concentrations of individual terpenes varied by cultivar. The present study suggests that using UV radiation as a production tool did not lead to any commercially relevant benefits to cannabis yield or inflorescence secondary metabolite composition.
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Affiliation(s)
| | | | - Youbin Zheng
- School of Environmental Sciences, University of Guelph, Guelph, ON, Canada
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Desaulniers Brousseau V, Wu BS, MacPherson S, Morello V, Lefsrud M. Cannabinoids and Terpenes: How Production of Photo-Protectants Can Be Manipulated to Enhance Cannabis sativa L. Phytochemistry. FRONTIERS IN PLANT SCIENCE 2021; 12:620021. [PMID: 34135916 PMCID: PMC8200639 DOI: 10.3389/fpls.2021.620021] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 05/07/2021] [Indexed: 05/02/2023]
Abstract
Cannabis sativa L. is cultivated for its secondary metabolites, of which the cannabinoids have documented health benefits and growing pharmaceutical potential. Recent legal cannabis production in North America and Europe has been accompanied by an increase in reported findings for optimization of naturally occurring and synthetic cannabinoid production. Of the many environmental cues that can be manipulated during plant growth in controlled environments, cannabis cultivation with different lighting spectra indicates differential production and accumulation of medically important cannabinoids, including Δ9-tetrahydrocannabinol (Δ9-THC), cannabidiol (CBD), and cannabigerol (CBG), as well as terpenes and flavonoids. Ultraviolet (UV) radiation shows potential in stimulating cannabinoid biosynthesis in cannabis trichomes and pre-harvest or post-harvest UV treatment merits further exploration to determine if plant secondary metabolite accumulation could be enhanced in this manner. Visible LED light can augment THC and terpene accumulation, but not CBD. Well-designed experiments with light wavelengths other than blue and red light will provide more insight into light-dependent regulatory and molecular pathways in cannabis. Lighting strategies such as subcanopy lighting and varied light spectra at different developmental stages can lower energy consumption and optimize cannabis PSM production. Although evidence demonstrates that secondary metabolites in cannabis may be modulated by the light spectrum like other plant species, several questions remain for cannabinoid production pathways in this fast-paced and growing industry. In summarizing recent research progress on light spectra and secondary metabolites in cannabis, along with pertinent light responses in model plant species, future research directions are presented.
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Affiliation(s)
| | | | | | | | - Mark Lefsrud
- Department of Bioresource Engineering, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
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