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Collado CE, Hwang SJ, Hernández R. Supplemental greenhouse lighting increased the water use efficiency, crop growth, and cutting production in Cannabis sativa. FRONTIERS IN PLANT SCIENCE 2024; 15:1371702. [PMID: 38911978 PMCID: PMC11190854 DOI: 10.3389/fpls.2024.1371702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 05/06/2024] [Indexed: 06/25/2024]
Abstract
The expanding cannabis production sector faces economic challenges, intensified by freshwater scarcity in the main US production areas. Greenhouse cultivation harnesses sunlight to reduce production costs, yet the impact of greenhouse light levels on crucial production components, such as plant growth, branching, and water use efficiency (WUE), remains poorly understood. This study aimed to assess the effects of combined sunlight and supplemental lighting on the crop's main production components and leaf gas exchange of Cannabis sativa 'Suver Haze' in the vegetative stage. Within a greenhouse, LED lighting provided at intensities of ~150, 300, 500, and 700 µmol m-2 s-1 (18-hour photoperiod), combined with solar radiation, resulted in average daily light integrals of 17.9, 29.8, 39.5, and 51.8 mol m-2 d-1. Increasing light levels linearly increased biomass, leaf area, and the number of branches per plant and square meter, with respective rates of 0.26 g, 32.5 cm2, and 0.41 branches per mole of additional light. As anticipated, crop evapotranspiration increased by 1.8-fold with the increase in light intensity yet crop WUE improved by 1.6-fold when comparing the lowest and highest light treatments. Moreover, water requirements per unit of plant biomass decreased from 0.37 to 0.24 liters per gram when lighting increased from ~18 to 52 mol m-2 d-1, marking a 35% reduction in evapotranspiration. These results were supported by increments in leaf photosynthesis and WUE with light enhancement. Furthermore, our findings indicate that even 52 mol m-2 d-1 of supplemental lighting did not saturate any of the crop responses to light and can be economically viable for cannabis nurseries. In conclusion, light supplementation strongly enhanced photosynthesis and plant growth while increasing WUE. Additionally, a comprehensive discussion highlights the shared physiological mechanisms governing WUE in diverse plant species and their potential for water conservation under enhanced lighting conditions.
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Affiliation(s)
- Cristian E. Collado
- Department of Horticultural Science, North Carolina State University, Raleigh, NC, United States
| | - Seung Jae Hwang
- Division of Horticultural Sciences, Institute of Agriculture & Life Sciences, Research Institute of Life Sciences, Division of Crop Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - Ricardo Hernández
- Department of Horticultural Science, North Carolina State University, Raleigh, NC, United States
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Slosse A, Van Durme F, Samyn N, Mangelings D, Vander Heyden Y. Cannabis profiling of seized samples: An intra-location variability study using gas chromatography-mass spectrometry profiles and multivariate data analysis. Drug Test Anal 2024; 16:504-514. [PMID: 37691538 DOI: 10.1002/dta.3574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/27/2023] [Accepted: 08/30/2023] [Indexed: 09/12/2023]
Abstract
Yearly, cannabis belongs to the most seized drugs worldwide. During judicial investigations, illicit cannabis profiling can be performed to compare seized herbal material. However, comparison is challenging because of the natural heterogeneity of the psychoactive crop. Gas chromatography-mass spectrometry (GC-MS) profiles, consisting of eight cannabinoids, were used to study the intra-location (within) and inter-location (between) variabilities. Decision thresholds were derived from the 95% and 99% confidence limits, applying Pearson correlation coefficients for the intra-location samples. The false negatives and false positives (FPs) determined the discriminative power of different pretreatments applied to obtain the lowest FP error rate possible. Initially, a 97 samples data set was used and with log transformation as pretreatment, a decrease in FPs from 38% and 45% FPs to 17% and 22%, for both confidence limits, respectively, was seen relative to internal standard normalization that was used as reference. An additional intra-plantation variability study with 130 samples verified whether the initial model contained sufficient within-location information, but this was not the case. Hence, a combined data matrix was constructed with all seized samples. Log transformation provided the best FP results for both limits, that is, an improvement from 58% and 64% to 21% and 26%, respectively, was seen. The representativeness of these 'linked' thresholds was demonstrated using both cross-validation and an external set, for which similar FP results as for the calibration set were obtained. By applying data pretreatment, a significant improvement was observed to distinguish seized samples. However, the FP rate is still not at an acceptable level to defend in court.
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Affiliation(s)
- Amorn Slosse
- Department of Analytical Chemistry, Applied Chemometrics and Molecular Modelling, Vrije Universiteit Brussel (VUB), Brussels, Belgium
- Department Drugs and Toxicology, National Institute for Criminalistics and Criminology (NICC), Brussels, Belgium
| | - Filip Van Durme
- Department Drugs and Toxicology, National Institute for Criminalistics and Criminology (NICC), Brussels, Belgium
| | - Nele Samyn
- Department Drugs and Toxicology, National Institute for Criminalistics and Criminology (NICC), Brussels, Belgium
| | - Debby Mangelings
- Department of Analytical Chemistry, Applied Chemometrics and Molecular Modelling, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Yvan Vander Heyden
- Department of Analytical Chemistry, Applied Chemometrics and Molecular Modelling, Vrije Universiteit Brussel (VUB), Brussels, Belgium
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Malík M, Velechovský J, Tlustoš P. The overview of existing knowledge on medical cannabis plants growing. PLANT, SOIL AND ENVIRONMENT 2021. [PMID: 0 DOI: 10.17221/96/2021-pse] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
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4
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Evaluation of data preprocessings for the comparison of GC–MS chemical profiles of seized cannabis samples. Forensic Sci Int 2020; 310:110228. [DOI: 10.1016/j.forsciint.2020.110228] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 02/18/2020] [Accepted: 02/27/2020] [Indexed: 11/17/2022]
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Belackova V, Roubalova (Stefunkova) M, van de Ven K. Overview of “home” cultivation policies and the case for community-based cannabis supply. THE INTERNATIONAL JOURNAL OF DRUG POLICY 2019; 71:36-46. [DOI: 10.1016/j.drugpo.2019.05.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 03/28/2019] [Accepted: 05/20/2019] [Indexed: 01/21/2023]
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Lyu D, Backer R, Robinson WG, Smith DL. Plant Growth-Promoting Rhizobacteria for Cannabis Production: Yield, Cannabinoid Profile and Disease Resistance. Front Microbiol 2019; 10:1761. [PMID: 31456755 PMCID: PMC6698789 DOI: 10.3389/fmicb.2019.01761] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 07/16/2019] [Indexed: 12/14/2022] Open
Abstract
Legal Cannabis production is now experiencing growing consumer demand due to changing legislation around the world. However, because of heavy restrictions on cannabis cultivation over the past century, little scientific research has been conducted on this crop, in particular around use of members of the phytomicrobiome to improve crop yields. Recent developments in the field of plant science have demonstrated that application of microbes, isolated from the rhizosphere, have enormous potential to improve yields, in particular under stressful growing conditions. This perspective carefully examines the potential for plant growth-promoting rhizobacteria (PGPR) to improve marijuana and hemp yield and quality. It then explores the potential use of PGPR for biological control of plant pathogens, which is particularly interesting given the stringent regulation of pesticide residues on this crop. As an industry-relevant example, biocontrol of powdery mildew, a common and deleterious pathogen affecting cannabis production, is assessed. Finally, two PGPR in genera frequently associated with higher plants (Pseudomonas and Bacillus) were selected as case studies for the potential effects on growth promotion and disease biocontrol in commercial cannabis production.
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Affiliation(s)
- Dongmei Lyu
- Crop Physiology Laboratory, Department of Plant Science, McGill University, Montreal, QC, Canada
| | - Rachel Backer
- Crop Physiology Laboratory, Department of Plant Science, McGill University, Montreal, QC, Canada
| | | | - Donald L. Smith
- Crop Physiology Laboratory, Department of Plant Science, McGill University, Montreal, QC, Canada
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Eichhorn Bilodeau S, Wu BS, Rufyikiri AS, MacPherson S, Lefsrud M. An Update on Plant Photobiology and Implications for Cannabis Production. FRONTIERS IN PLANT SCIENCE 2019; 10:296. [PMID: 31001288 PMCID: PMC6455078 DOI: 10.3389/fpls.2019.00296] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 02/25/2019] [Indexed: 05/18/2023]
Abstract
This review presents recent developments in plant photobiology and lighting systems for horticultural crops, as well as potential applications for cannabis (Cannabis sativa and C. indica) plant production. The legal and commercial production of the cannabis plant is a relatively new, rapidly growing, and highly profitable industry in Europe and North America. However, more knowledge transfer from plant studies and horticultural communities to commercial cannabis plant growers is needed. Plant photosynthesis and photomorphogenesis are influenced by light wavelength, intensity, and photoperiod via plant photoreceptors that sense light and control plant growth. Further, light properties play a critical role in plant vegetative growth and reproductive (flowering) developmental stages, as well as in biomass, secondary metabolite synthesis, and accumulation. Advantages and disadvantages of widespread greenhouse lighting systems that use high pressure sodium lamps or light emitting diode (LED) lighting are known. Some artificial plant lighting practices will require improvements for cannabis production. By manipulating LED light spectra and stimulating specific plant photoreceptors, it may be possible to minimize operation costs while maximizing cannabis biomass and cannabinoid yield, including tetrahydrocannabinol (or Δ9-tetrahydrocannabinol) and cannabidiol for medicinal and recreational purposes. The basics of plant photobiology (photosynthesis and photomorphogenesis) and electrical lighting systems are discussed, with an emphasis on how the light spectrum and lighting strategies could influence cannabis production and secondary compound accumulation.
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Affiliation(s)
| | | | | | | | - Mark Lefsrud
- Department of Bioresource Engineering, McGill University, Montreal, QC, Canada
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Backer R, Schwinghamer T, Rosenbaum P, McCarty V, Eichhorn Bilodeau S, Lyu D, Ahmed MB, Robinson G, Lefsrud M, Wilkins O, Smith DL. Closing the Yield Gap for Cannabis: A Meta-Analysis of Factors Determining Cannabis Yield. FRONTIERS IN PLANT SCIENCE 2019; 10:495. [PMID: 31068957 PMCID: PMC6491815 DOI: 10.3389/fpls.2019.00495] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 04/01/2019] [Indexed: 05/20/2023]
Abstract
Until recently, the commercial production of Cannabis sativa was restricted to varieties that yielded high-quality fiber while producing low levels of the psychoactive cannabinoid tetrahydrocannabinol (THC). In the last few years, a number of jurisdictions have legalized the production of medical and/or recreational cannabis with higher levels of THC, and other jurisdictions seem poised to follow suit. Consequently, demand for industrial-scale production of high yield cannabis with consistent cannabinoid profiles is expected to increase. In this paper we highlight that currently, projected annual production of cannabis is based largely on facility size, not yield per square meter. This meta-analysis of cannabis yields reported in scientific literature aimed to identify the main factors contributing to cannabis yield per plant, per square meter, and per W of lighting electricity. In line with previous research we found that variety, plant density, light intensity and fertilization influence cannabis yield and cannabinoid content; we also identified pot size, light type and duration of the flowering period as predictors of yield and THC accumulation. We provide insight into the critical role of light intensity, quality, and photoperiod in determining cannabis yields, with particular focus on the potential for light-emitting diodes (LEDs) to improve growth and reduce energy requirements. We propose that the vast amount of genomics data currently available for cannabis can be used to better understand the effect of genotype on yield. Finally, we describe diversification that is likely to emerge in cannabis growing systems and examine the potential role of plant-growth promoting rhizobacteria (PGPR) for growth promotion, regulation of cannabinoid biosynthesis, and biocontrol.
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Affiliation(s)
- Rachel Backer
- Crop Physiology Laboratory, Department of Plant Science, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
- *Correspondence: Rachel Backer
| | - Timothy Schwinghamer
- Crop Physiology Laboratory, Department of Plant Science, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
| | - Phillip Rosenbaum
- Plant Systems Biology Laboratory, Department of Plant Science, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
| | - Vincent McCarty
- Plant Systems Biology Laboratory, Department of Plant Science, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
| | - Samuel Eichhorn Bilodeau
- Biomass Production Laboratory, Department of Bioresource Engineering, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
| | - Dongmei Lyu
- Crop Physiology Laboratory, Department of Plant Science, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
| | - Md Bulbul Ahmed
- Plant Systems Biology Laboratory, Department of Plant Science, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
| | | | - Mark Lefsrud
- Biomass Production Laboratory, Department of Bioresource Engineering, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
| | - Olivia Wilkins
- Plant Systems Biology Laboratory, Department of Plant Science, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
| | - Donald L. Smith
- Crop Physiology Laboratory, Department of Plant Science, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
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“The difference is in the tomato at the end”: Understanding the motivations and practices of cannabis growers operating within Belgian Cannabis Social Clubs. THE INTERNATIONAL JOURNAL OF DRUG POLICY 2018. [DOI: 10.1016/j.drugpo.2018.02.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Vanhove W, Maalsté N, Van Damme P. Why is it so difficult to determine the yield of indoor cannabis plantations? A case study from the Netherlands. Forensic Sci Int 2017; 276:e20-e29. [PMID: 28502714 DOI: 10.1016/j.forsciint.2017.03.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 03/22/2017] [Accepted: 03/23/2017] [Indexed: 10/19/2022]
Abstract
Together, the Netherlands and Belgium are the largest indoor cannabis producing countries in Europe. In both countries, legal prosecution procedure of convicted illicit cannabis growers usually includes recovery of the profits gained. However, it is not easy to make a reliable estimation of the latter profits, due to the wide range of factors that determine indoor cannabis yields and eventual selling prices. In the Netherlands, since 2005, a reference model is used that assumes a constant yield (g) per plant for a given indoor cannabis plant density. Later, in 2011, a new model was developed in Belgium for yield estimation of Belgian indoor cannabis plantations that assumes a constant yield per m2 of growth surface, provided that a number of growth conditions are met. Indoor cannabis plantations in the Netherlands and Belgium share similar technical characteristics. As a result, for indoor cannabis plantations in both countries, both aforementioned yield estimation models should yield similar yield estimations. By means of a real-case study from the Netherlands, we show that the reliability of both models is hampered by a number of flaws and unmet preconditions. The Dutch model is based on a regression equation that makes use of ill-defined plant development stages, assumes a linear plant growth, does not discriminate between different plantation size categories and does not include other important yield determining factors (such as fertilization). The Belgian model addresses some of the latter shortcomings, but its applicability is constrained by a number of pre-conditions including plantation size between 50 and 1000 plants; cultivation in individual pots with peat soil; 600W (electrical power) assimilation lamps; constant temperature between 20°C and 30°C; adequate fertilizer application and plants unaffected by pests and diseases. Judiciary in both the Netherlands and Belgium require robust indoor cannabis yield models for adequate legal prosecution of illicit indoor cannabis growth operations. To that aim, the current models should be optimized whereas the validity of their application should be examined case by case.
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Affiliation(s)
- Wouter Vanhove
- Ghent University, Faculty of Bio-Science Engineering, Department of Plant Production, Tropical and Subtropical Agriculture and Ethnobotany, Coupure Links 653, 9000 Ghent, Belgium.
| | - Nicole Maalsté
- Acces Interdit, Juffrouw Idastraat 11, 2513 BE Den Haag, Netherlands.
| | - Patrick Van Damme
- Ghent University, Faculty of Bio-Science Engineering, Department of Plant Production, Tropical and Subtropical Agriculture and Ethnobotany, Coupure Links 653, 9000 Ghent, Belgium; Czech University of Life Sciences Prague, Faculty of Tropical AgriSciences, Kamycka 129, Prague 6 - Suchdol, 165 21, Czech Republic.
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Filling in the blanks. An estimation of illicit cannabis growers' profits in Belgium. THE INTERNATIONAL JOURNAL OF DRUG POLICY 2014; 25:436-43. [PMID: 24635974 DOI: 10.1016/j.drugpo.2014.01.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 12/18/2013] [Accepted: 01/28/2014] [Indexed: 11/23/2022]
Abstract
BACKGROUND As a result of increased pressure on cannabis cultivation in The Netherlands, the number of confiscated indoor cannabis plantations in Belgium is rising. Although increases are reported for all plantations sizes, half of the seized plantations contain less than 50 plants. In this study, factors and variables that influence costs and benefits of indoor cannabis cultivation are investigated as well as how these costs and benefits vary between different cannabis grower types. METHODS Real-situation data of four growers were used to perform financial analyses. Costs included fixed and variable material costs, as well as opportunity costs. Gross revenue per grow cycle was calculated based on most recent forensic findings for illicit Belgian cannabis plantations and was adjusted for the risk of getting caught. Finally, gross revenues and return on costs (ROC) were calculated over 1 year (4 cycles). FINDINGS Financial analysis shows that in all cases gross revenues as well as ROC are considerable, even after a single growth cycle. Highest profitability was found for large-scale (600 plants, ROC=6.8) and mid-scale plantations (150 plants, ROC=6.0). However, industrial plantations (23,000 plants, ROC=1.4) and micro-scale plantations (5 plants, ROC=2.8) are also highly remunerative. Shift of police focus away from micro-scale growers, least likely to be involved in criminal gangs, to large-scale and industrial scale plantations would influence costs as a result of changing risks of getting caught. However, sensitivity analysis shows that this does not significantly influence the conclusions on profitability of different types of indoor cannabis growers. CONCLUSION Seizure and confiscation of profits are important elements in the integral and integrated policy approach required for tackling illicit indoor cannabis plantations. The large return of costs evidenced in the present study, underpin the policy relevance of confiscating those illicit profits as part of enforcement.
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