Article

Evolution and Classification of Cannabis sativa (Marijuana, Hemp) in Relation to Human Utilization

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  • Agriculture Canada
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Abstract

Cannabis sativa has been employed for thousands of years, primarily as a source of a stem fiber (both the plant and the fiber termed “hemp”) and a resinous intoxicant (the plant and its drug preparations commonly termed “marijuana”). Studies of relationships among various groups of domesticated forms of the species and wild-growing plants have led to conflicting evolutionary interpretations and different classifications, including splitting C. sativa into several alleged species. This review examines the evolving ways Cannabis has been used from ancient times to the present, and how human selection has altered the morphology, chemistry, distribution and ecology of domesticated forms by comparison with related wild plants. Special attention is given to classification, since this has been extremely contentious, and is a key to understanding, exploiting and controlling the plant. Differences that have been used to recognize cultivated groups within Cannabis are the results of disruptive selection for characteristics selected by humans. Wild-growing plants, insofar as has been determined, are either escapes from domesticated forms or the results of thousands of years of widespread genetic exchange with domesticated plants, making it impossible to determine if unaltered primeval or ancestral populations still exist. The conflicting approaches to classifying and naming plants with such interacting domesticated and wild forms are examined. It is recommended that Cannabis sativa be recognized as a single species, within which there is a narcotic subspecies with both domesticated and ruderal varieties, and similarly a non-narcotic subspecies with both domesticated and ruderal varieties. An alternative approach consistent with the international code of nomenclature for cultivated plants is proposed, recognizing six groups: two composed of essentially non-narcotic fiber and oilseed cultivars as well as an additional group composed of their hybrids; and two composed of narcotic strains as well as an additional group composed of their hybrids.

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... While hemp cultivars harvested for fiber production tend to have a tall stature with elongated stem internodes yielding long bast fibers, oilseed cultivars usually display a short branching architecture producing lots of nutritious seeds (Small, 2015). Fiber and oilseed hemp cultivars must also yield low levels of -9-tetrahydrocannabinol (THC)-the main psychoactive cannabinoid compound of cannabis-to comply with laws in North America and Europe that define hemp as containing up to 0.3% of THC and/or its acidic precursor on a dry weight basis. ...
... These drug-type crops (e.g., marijuana and hemp cultivars grown for phytochemical production, including THC and/or CBD) are very lucrative and are generally reproduced vegetatively by clonal cuttings from elite female plants with desirable genotypes, then transplanted in enclosed outdoor plots, secured greenhouses, or indoor cultivation rooms. Contrastingly, commercial fiber and oilseed hemp crops are mostly directly seeded in agricultural fields for cost efficiency (Small, 2015;Thiessen et al., 2020). ...
... Traditional retting is accomplished by exposing the harvested stems to decaying microorganisms in the field (dew retting), or by immersing the stems in large water tanks (water retting), to degrade pectins and other binding components. The long bast fibers are then extracted from the retted stalks by a mechanical decortication step, and transformed into textiles and other applications (Small, 2015). Fiber hemp cultivars have thus been selected to exhibit key desirable traits, like biomass yield, ease of retting, and bast fiber content, length, and strength (Schluttenhofer and Yuan, 2017). ...
Article
Full-text available
Among the oldest domesticated crops, cannabis plants ( Cannabis sativa L., marijuana and hemp) have been used to produce food, fiber, and drugs for thousands of years. With the ongoing legalization of cannabis in several jurisdictions worldwide, a new high-value market is emerging for the supply of marijuana and hemp products. This creates unprecedented challenges to achieve better yields and environmental sustainability, while lowering production costs. In this review, we discuss the opportunities and challenges pertaining to the use of beneficial Pseudomonas spp. bacteria as crop inoculants to improve productivity. The prevalence and diversity of naturally occurring Pseudomonas strains within the cannabis microbiome is overviewed, followed by their potential mechanisms involved in plant growth promotion and tolerance to abiotic and biotic stresses. Emphasis is placed on specific aspects relevant for hemp and marijuana crops in various production systems. Finally, factors likely to influence inoculant efficacy are provided, along with strategies to identify promising strains, overcome commercialization bottlenecks, and design adapted formulations. This work aims at supporting the development of the cannabis industry in a sustainable way, by exploiting the many beneficial attributes of Pseudomonas spp.
... The last decade has witnessed a revival of interest in Cannabis research, especially in relation to the genetic and phytochemical features of the different varieties and to its evolutionary origin, domestication and further geographic diffusion (e.g., Clarke & Merlin, 2013;Small, 2015;Gray et al., 2016b;Vergara et al., 2016). For example, the use of modern methods of molecular analysis has helped clarify the taxonomy of the Cannabis complex and its genetic modifications over time as a result of artificial (human-mediated) selection during the domestication process (Clarke & Merlin, 2016). ...
... A number of new varieties have been obtained from these two original subspecies by artificial selection, which have different morphologies, phytochemical compositions, geographic distributions and uses (Clarke & Merlin, 2016;Lynch et al., 2016;Rahn et al., 2016). According to Small (2015), the consequences of artificial selection make it impossible to determine if unaltered primeval or ancestral populations still exist. This author recommends that C. sativa be recognized as a single species with a narcotic subspecies (drug) and a non-narcotic subspecies (hemp), each with domesticated and ruderal varieties. ...
... During germination, seeds are surrounded by bracts with hairs that produce a resinous blend of cannabinoids and aromatic compounds as secondary metabolites, which are believed to protect seeds against pests and pathogens. Cannabinols may be psychoactive (THC) or not psychoactive (CBD) for humans (Small, 2015;Clarke & Merlin, 2016). ...
Preprint
Cannabis is among the oldest human domesticates and has been subjected to intensive artificial (human-mediated) selection throughout history to create a wide array of varieties and biotypes for diverse uses, including fibre, food, biofuel, medicine and drugs. This paper briefly reviews the available literature on the taxonomy, evolutionary origin and domestication of this plant, as well as its worldwide dispersal, in both its wild and cultivated forms. Emphasis is placed on Europe and especially on the Iberian Peninsula. Today, it is accepted that Cannabis is a monospecific genus with two subspecies, C. sativa subsp. sativa and C. sativa subsp. indica, originating in Europe and Asia, respectively, by allopatric differentiation after geographic isolation fostered by Pleistocene glacial-interglacial cycles. Palynological and phylogeographic evidence situates the Cannabis ancestor on the NE Tibetan Plateau during the mid-Oligocene. The timing and place of domestication is still a matter of debate between contrasting views that defend single or multiple Neolithic domestication centres situated in different parts of the Eurasian supercontinent, notably central/southeastern China and the Caucasus region. Recent meta-analyses have suggested that wild Cannabis may have already been spread across Europe in the Pleistocene, and its domestication could have occurred during the European Copper/Bronze ages. According to the available reviews and meta-analyses, pre-anthropic dispersal of Cannabis into the Iberian Peninsula seems to have occurred only in postglacial times, and the earlier signs of cultivation date to the Early Medieval Ages. However, the palynological and archaeological evidence used to date is insufficient for a sound assessment, and the development of thorough Iberian databases to address further meta-analysis is essential for more robust conclusions. Some clues are provided for these achievements to be fulfilled.
... The last decade has witnessed a revival of interest in Cannabis research, especially in relation to the genetic and phytochemical features of the different varieties and to its evolutionary origin, domestication and further geographic diffusion (e.g., Clarke and Merlin 2013;Small 2015;Gray et al. 2016b;Vergara et al. 2016). For example, the use of modern methods of molecular analysis has helped clarify the taxonomy of the Cannabis complex and its genetic modifications over time as a result of artificial (human-mediated) selection during the domestication process (Clarke and Merlin 2016). ...
... A number of new varieties have been obtained from these two original subspecies by artificial selection, which have different morphologies, phytochemical compositions, geographic distributions and uses (Clarke and Merlin 2016;Lynch et al. 2016;Rahn et al. 2016). According to Small (2015), the consequences of artificial selection make it impossible to determine if unaltered primeval or ancestral populations still exist. This author recommends that C. sativa be recognized as a single species with a narcotic subspecies (drug) and a non-narcotic subspecies (hemp), each with domesticated and ruderal varieties. ...
... During germination, seeds are surrounded by bracts with hairs that produce a resinous blend of cannabinoids and aromatic compounds as secondary metabolites, which are believed to protect seeds against pests and pathogens. Cannabinols may be psychoactive (THC) or not psychoactive (CBD) for humans (Small 2015;Clarke and Merlin 2016). ...
Preprint
Cannabis is among the oldest human domesticates and has been subjected to intensive artificial (human-mediated) selection through history, to create a wide array of varieties and biotypes for a diversity or uses, including fiber, food, biofuel, medicine and drugs, among others. This paper briefly reviews the available literature on the taxonomy, the evolutionary origin and the domestication of this plant, as well as its worldwide dispersal, either in its wild and cultivated forms. Emphasis is placed on Europe and especially on the Iberian Peninsula, which is the main target of this study. Today it is accepted that Cannabis is a monospecific genus with two subspecies, C. sativa subsp. sativa and C. sativa subsp. indica, originated in Europe and Asia, respectively, by allopatric differentiation after geographical isolation fostered by Pleistocene glacial-interglacial cycles. Palynological and phylogeographical evidence situate the Cannabis ancestor in the NE Tibetan Plateau during the Oligocene (ca. 28 Ma). The timing and place of domestication is still a matter of debate between contrasting views that defend single or multiple domestication centers, situated in different parts of the Eurasian supercontinent, notably central/southeastern China and the Caucasus region. Recent meta-analyses suggest that wild Cannabis may have been spread across Europe already in the Pleistocene (ca. 1 Ma), and its domestication could have been occurred during the European Copper/Bronze ages (7-5 kyr BP). According to the available reviews and meta-analyses, pre-anthropic dispersal of Cannabis into the Iberian Peninsula seems to have been occurred only in post-glacial times (18.5-15 kyr BP) and the earlier signs of cultivation date to the Early Medieval Ages (ca. 600 CE). However, the palynological and archaeological evidence used to date is insufficient for a sound assessment and the development of thorough Iberian databases to address further meta-analysis are essential for more robust conclusions. Some clues are provided for these achievements to be fulfilled.
... The European Union allows up to 0.2% and Switzerland allows up to 1% of THC content (Hazekamp 2018). Small (2015) has reported an interesting summary of C. sativa use, domestication and cultivation by humans. Along with human utilization, it has been evolved as one of the most useful and controversial plant species (Small 2015;Cerino et al. 2021). ...
... Small (2015) has reported an interesting summary of C. sativa use, domestication and cultivation by humans. Along with human utilization, it has been evolved as one of the most useful and controversial plant species (Small 2015;Cerino et al. 2021). Hundreds of vernacular names have been used for C. sativa such as weed, hemp, marijuana, Ganja, Bhang, etc. ...
... Hundreds of vernacular names have been used for C. sativa such as weed, hemp, marijuana, Ganja, Bhang, etc. As explained earlier, hemp is the name commonly used for the cultivar grown for obtaining the fiber having low contents of THC and marijuana is the common name for the cultivar used for euphoric and therapeutic properties having high contents of THC (Small 2015;Cerino et al. 2021). Hempseed is the common name for the seeds used to obtain oil for various purposes. ...
Chapter
Cannabis is the most versatile species. Hemp and marijuana have been used for fibre, oil, medicinal and recreational purposes from millennia. Throughout the last century, the plant has been generally outlawed because of its psychotropic effects in many nations. In recent past, the studies on cannabis revealed the evidence of its high medicinal properties and its uses in treating life threatening diseases, which leads to the relaxation of legislation in many counties. Now, the genetic and genomics as well as the cannabis derived products enjoys renewed attention. In this chapter, the discussion was made on the advent of genomics and breeding strategies to improve various traits of cannabis. This will bring insights on future direction of cannabis breeding.
... (1.2-1.5 m; semi-dwarf tall), and 6-7 ft. (1.8-2.1 m; medium height; Small, 2015). The plant contains nodes at intervals of 10 to 50 cm. ...
... The plant contains nodes at intervals of 10 to 50 cm. The leaflets are dark green, serrated, and taper at each end in 5 to 11 points (Small, 2015). The leaves grow up to 15 cm in length and 12 cm in width (Ehrensing, 1998;Kraenzel et al., 1998). ...
Article
Full-text available
Forensic laboratories are required to have analytical tools to confidently differentiate illegal substances such as marijuana from legal products (i.e., industrial hemp). The Achilles heel of industrial hemp is its association with marijuana. Industrial hemp from the Cannabis sativa L. plant is reported to be one of the strongest natural multipurpose fibers on earth. The Cannabis plant is a vigorous annual crop broadly separated into two classes: industrial hemp and marijuana. Up until the eighteenth century, hemp was one of the major fibers in the United States. The decline of its cultivation and applications is largely due to burgeoning manufacture of synthetic fibers. Traditional composite materials such as concrete, fiberglass insulation, and lumber are environmentally unfavorable. Industrial hemp exhibits environmental sustainability, low maintenance, and high local and national economic impacts. The 2018 Farm Bill made way for the legalization of hemp by categorizing it as an ordinary agricultural commodity. Unlike marijuana, hemp contains less than 0.3% of the cannabinoid, Δ9-tetrahydrocannabinol, the psychoactive compound which gives users psychotropic effects and confers illegality in some locations. On the other hand, industrial hemp contains cannabidiol found in the resinous flower of Cannabis and is purported to have multiple advantageous uses. There is a paucity of investigations of the identity, microbial diversity, and biochemical characterizations of industrial hemp. This review provides background on important topics regarding hemp and the quantification of total tetrahydrocannabinol in hemp products. It will also serve as an overview of emergent microbiological studies regarding hemp inflorescences. Further, we examine challenges in using forensic analytical methodologies tasked to distinguish legal fiber-type material from illegal drug-types.
... indica and subsp. ruderalis), because of the absence of evidence for reproductive barriers to interbreeding among these Cannabis populations [10,11,12,13,14]. It is generally believed that sativa are tall and branched plants for ber and seed, indica are short and branching plants utilized to produce hashish, ruderalis are short, unbranched plants usually weak in cannabinoids [8,15]. ...
... China is also rich in cannabis germplasm resources across most of the mainland, ranging from approximately 23 to 51°N except for the southeast coastal areas [14]. Taxonomists recognize different population types for cannabis based on natural origins, agronomic characters and associations with humans [8,12]. Most Chinese resources are landraces and have been domesticated for hundreds of years for different purposes, gradually forming different local types such as seed type, ber type, medicinal type and other local types. ...
Preprint
Full-text available
Background: Cannabis is an important industrial crop, whose bast fiber, seed, flowers and leaves are widely used by humans,especially cannabinoids extracted from plants as medicine is a hot spot in recent years. China is one of the origins of cannabis, where it has been cultivated and utilized for more than 6000 years, with the largest planting area of industrial hemp at present. China is rich in cannabis germplasm resources covering different latitudes (23 to 51°N) and is one of the few countries with wild cannabis resources. However, the genetic structure of Chinese cannabis populations and the adaptive selection of important traits remain unclear. Results: We identified the main morphological and physiological characteristics of wild cannabis and defined the genetic structure and relationships among wild and cultivated Chinese cannabis accessions and foreign representatives. This suggested that wild resources in Xinjiang have played an important role in the process of cannabis domestication. Adaptive selection analysis revealed that cultivated cannabis has undergone selective evolution or adaptation in flowering, growth and stress tolerance, and many functional genes were identified. Flowering characteristics analysis implied that wild cannabis is native to high latitudes and possesses the typical characteristic of early flowering, while cultivated cannabis has undergone a process of adaptive evolution to adjust to natural photoperiod conditions in different latitudes through regulation of FT-like expression. Conclusion: This study clarifies the genetic structure of Chinese cannabis and provides insight into adaptive selection and breeding in cannabis.
... Additionally, the term "hemp seed" is recognized when the material is used as a source of seed oil. For ganja, the resinous blend of cannabinoids that localized mainly in the trichomes of floral tissues is used for recreational or as therapeutic drugs (Small 2015;Clarke and Merlin 2016). The international criteria, nonetheless, deems CBD as the major cannabinoid composition in the floral tissue of industrial hemp which is typically about 2% weight by weight (w/w) or less, and THC should be less than 0.3% w/w, although the European Union standard is not over 0.2% w/w (Hu et al. 2019). ...
... Male plants that flower earlier are removed during the early flowering stage, and female plants are kept under the 12-h photoperiod until they reach maturity (Chandra et al. 2017;Chandra et al. 2020). In fact, when grown in hot, dry regions, the temperate hemp seedlings can transform into the narcotic cultivars (Small 2015;Bouquet 1950). Based on the current Thai law, the term ganja seed is ambiguous. ...
Article
Full-text available
The current revision to Thailand's Narcotics Act (B.E. 2563) permits Thai corporations to produce cannabis (ganja) for therapeutic purposes, as well as conduct beneficial research and development in science and agriculture. While ganja possession, distribution, and use are still illegal in Thailand, the law removes certain elements of Cannabis sativa (including hemp) from the narcotic lists as of December 2020 and Thailand's narcotics board plans to remove them totally from the lists before the last quarter of 2022. The Thai Food and Drug Administration (Thai FDA) board maintains the exclusive licensing authority to assess applications and provide authorization due to the complexity of the registration process. In this view, we analyzed the guidelines for obtaining cannabis production license, and it was apparent that the announced law was in-line with regulations set-out by many countries in terms of security and prevention of misuse. The other criteria however fall merely onto the government gains, rather than public interests. To avoid the claimed state monopoly, several types of licensing should be issued in the future, depending on the genuine purpose of the farmers. The complete regulation process and conditions for obtaining a ganja growing license in Thailand are highlighted and discussed in this review.
... Notwithstanding the clear advantages of the conventional regulatory pathway (European Monitoring Centre for Drugs and Drug Addiction 2018b; Belackova et al. 2018), there are still few pathological conditions for which there is sufficient clinical evidence on the safety and efficacy of cannabis-based medicines (see the "Background" section). This can be attributed, at least in part, to the access difficulties arising from the strict controls imposed on cannabis, even when it comes exclusively to scientific research-related activities (Small 2015). It is also worth mentioning that the inherent variability in the chemical composition and the lack of appropriate characterization of herbal extracts are complicating factors in the process of drawing conclusions from the results of a set of different clinical trials (Food and Drug Administration 2016). ...
... As well as other medicines, medical cannabis and its derivatives should have their use based on evidence of quality, safety, and efficacy (Health Products Regulatory Authority 2017; Government of Australia 2016). Nevertheless, the tendency to avoid investigating sensitive or controversial subjects, along with the difficulties imposed by international prohibitionist policies, has hampered scientific research on the therapeutic and pharmacological properties of the species, resulting in a knowledge gap that remains nowadays (Small 2015). As a consequence, the scientific data that would be required for the regularization of cannabis-based medicines through conventional regulatory pathways are sometimes insufficient (Health Products Regulatory Authority 2017). ...
Article
Cannabis sativa has accompanied humankind since ancient times, permeating the most diverse aspects of its existence, among which the search for health promotion and well-being stands out. Nevertheless, during the twentieth century, a series of restrictions and controls have been adopted internationally to prevent the abusive use of this species. Despite that, there has been an increased demand for the medical use of cannabis and its derivatives in the last few decades, especially among patients with debilitating conditions for which the existing therapeutic alternatives are limited. Accordingly, several countries have adopted regulatory strategies to allow access to cannabis-based products. This study aimed to overview the existing regulatory frameworks for medical cannabis around the world, focusing on the current Brazilian scenario. In addition to supply and access regulation aspects, some quality-related issues regarding cannabis-based pharmaceutical products were addressed, with emphasis on risks to patients. The literature research was performed between October 2020 and March 2021. According to the retrieved information, by the time the data collection was completed, thirty-six countries had already implemented regulatory frameworks regarding medical cannabis, and sixteen countries had models under development or in the process of implementation. The characteristics of the assessed regulatory strategies vary considerably from country to country, reflecting sociocultural, historical, and political aspects. Among the key aspects that differed between the assessed models, one can highlight the type of cannabis products that are made available and the technical requirements applied to them, as well as the possible access mechanisms. Different supply regulation strategies were also observed regarding cannabis cultivation, production licensing, and distribution mechanisms. In Brazil, an evolution of the regulatory framework has been noticeable since 2015, even though pending points are still to be addressed, among which are the species’ cultivation and the access to it for scientific research purposes. Constructing a regulatory model which provides access to good quality cannabis-based medicines that may meet the patient’s needs is still a challenge in the coming years, requiring the engagement of various stakeholders, including regulators, members of the academic community, prescribing professionals, and patients.
... For example, cannabis-infused chocolate is first soaked in IS solutions and isopropyl alcohol, extracted with MeCN + 1% acetic acid and finally diluted with MeCN prior to LC-MS/MS or MeCN/H 2 O (75:25, v/v) prior to HPLC-UV analysis [65]. Solvent exchange is also performed prior to GC analysis, especially when derivatization is performed [7,80,87,104,121,123,133]. Extracts are reduced to dryness usually under gentle N 2 steam, causing least damage to total extracted amounts of phytocannabinoids and terpenoids than drying in rotary evaporator or in a speedvac, the latter reducing the concentrations of ∆ 9 -THC and CBG for two-thirds [66]. ...
... Before instrumental analysis, decarboxylation may be also introduced, initiating thermal degradation of phytocannabinoid acids to neutral counterparts for the purpose of accurate phytocannabinoid profiling and potency examination. Dried extracts are most commonly heated at 150-210 • C for 10-30 min and reconstituted in the same solvent or solvent mixtures [7,52,60,101,128], or, alternatively, at 50 • C for 180 min and then 145 • C for 15 min [69]. A total 15 min of decarboxylation at a temperature range of 120-180 • C showed that maximum yield is achieved at 140-160 • C, with no significant within-range differences [115]. ...
Article
Full-text available
Cannabis is gaining increasing attention due to the high pharmacological potential and updated legislation authorizing multiple uses. The development of time- and cost-efficient analytical methods is of crucial importance for phytocannabinoid profiling. This review aims to capture the versatility of analytical methods for phytocannabinoid profiling of cannabis and cannabis-based products in the past four decades (1980–2021). The thorough overview of more than 220 scientific papers reporting different analytical techniques for phytocannabinoid profiling points out their respective advantages and drawbacks in terms of their complexity, duration, selectivity, sensitivity and robustness for their specific application, along with the most widely used sample preparation strategies. In particular, chromatographic and spectroscopic methods, are presented and discussed. Acquired knowledge of phytocannabinoid profile became extremely relevant and further enhanced chemotaxonomic classification, cultivation set-ups examination, association of medical and adverse health effects with potency and/or interplay of certain phytocannabinoids and other active constituents, quality control (QC), and stability studies, as well as development and harmonization of global quality standards. Further improvement in phytocannabinoid profiling should be focused on untargeted analysis using orthogonal analytical methods, which, joined with cheminformatics approaches for compound identification and MSLs, would lead to the identification of a multitude of new phytocannabinoids.
... The origination of cannabis was believed to be from Central Asia about~500 BC (Farag and Kayser 2017). Plants belongs to this genus are well grown in wet land sites and near water bodies, where the concentration of nitrogen are found high (Small 2015). Cannabis is highly used and described genus in Ayurveda to provide various pharmacological bioactive compounds and benefits. ...
... During the origination process of plant, particularly Hemp opened the path to hybridization and leads the development of thousands of cultivars. Small (2015) stated that there is a serious taxonomic issue to classify the different strains of Cannabis and divide the C. sativa L. species into 3 subspecies or variants such as 'sativa' (industrial cannabis/hemp having a limited amount of tetrahydrocannabinol or THC), 'indica' (medicinal cannabis/marijuana producing principally THC), and 'ruderalis' (known for wild hemp strains). Clarke and Merlin (2016) referred C. ruderalis as ancestor of two modern Cannabis sp. ...
Chapter
Cannabis sativa (hemp) as multifunctional crop have traditional application as fiber, food, paper, textile and pharmaceutical potential as inflorescences and seed as sources of exciting bioactive secondary metabolites. The Genus Cannabis is the only producer of phytocannabinoids. Extensive studied have been made to describe the origin history, geographical ranges and genetic identity of the Cannabis species but it remains obscured to date. Various high through put genetic marker have been studied to assess the genetic diversity in hemp varieties. Studies also indicated that domestication origin affects the genetic groups of hemp which further consequences on the chemical diversity of the cannabis. Chemotaxonomy using chemical markers also played a crucial role in differencing and allocating the Cannabis taxa. Cannabinoids ratio and terpene composition are the major marker to play an important role in studying chemical diversity of Cannabis sp. Cannabis genus is the only source of phytocannabinoids the dominant chemical class. Other than cannabinoids terpene and non-cannabinoid phenolic compounds also contribute in the chemical diversity of the species. The vast array of phytochemicals presents in the genus have potential application in pharmaceutical industries. However, due to its legalization status very limited study on its chemical and genetic diversity have been done. Therefore, the species needs attention to explore its commercial value.
... Cannabis sativa L. (cannabis) is an important medical and industrial crop; its use continues to expand as its consumption for both medicinal and recreational use increases [1]. Known as one of the oldest cultivated plants, cannabis originated in Central Asia and then spread throughout Asia and Europe [2][3][4]. The genus Cannabis is part of the Cannabaceae family, and despite controversy regarding the number of species comprising the genus, the most accepted assumption is that Cannabis is a monotypic genus (C. ...
... The genus Cannabis is part of the Cannabaceae family, and despite controversy regarding the number of species comprising the genus, the most accepted assumption is that Cannabis is a monotypic genus (C. sativa L.) with three sub-species: sativa, indica, and ruderalis [2][3][4][5]. Regardless of the differences in phenotypic appearance and chemical profile among the subspecies, intensive crossbreeding has resulted in the fading of the classical unique characteristics of each population [1,6]. ...
Article
Full-text available
Medical cannabis (Cannabis sativa L.) is quickly becoming a central agricultural crop as its production has continued to increase globally. The recent release of the cannabis reference genomes provides key genetic information for the functional analysis of cannabis genes. Currently, however, the established tools for in vivo gene functional analysis in cannabis are very limited. In this study, we investigated the use of the tobacco rattle virus (TRV) as a possible tool for virus-induced gene silencing (VIGS) and virus-aided gene expression (VAGE). Using leaf photobleaching as a visual marker of PHYTOENE DESATURASE (PDS) silencing, we found that VIGS was largely restricted to the agro-infiltrated leaves. However, when agro-infiltration was performed under vacuum, VIGS increased dramatically, which resulted in intense PDS silencing and an increased photobleaching phenotype. The suitability of TRV as a vector for virus-aided gene expression (VAGE) was demonstrated by an analysis of DsRed fluorescence protein. Interestingly, a DsRed signal was also observed in glandular trichomes in TRV2-DsRed-infected plants, which suggests the possibility of trichome-related gene function analysis. These results indicate that TRV, despite its limited spread, is an attractive vector for rapid reverse-genetics screens and for the analysis of gene function in cannabis.
... indica and subsp. ruderalis) because of the absence of evidence for reproductive barriers to interbreeding among these Cannabis populations [10][11][12][13][14]. ...
... Most Chinese resources are landraces and have been domesticated for hundreds of years for different purposes, which have gradually evolved into different local types, such as seed types, fibre types, medicinal types and other local types. Taxonomists recognize different cannabis population types based on their natural origins, agronomic characteristics, and associations with humans [8,12]. It is surprising that there are still many wild-like cannabis populations growing spontaneously in some areas, mainly distributed in the northeastern, northwestern and southwestern regions of China [21]. ...
Article
Full-text available
Background Cannabis is an important industrial crop species whose fibre, seeds, flowers and leaves are widely used by humans. The study of cannabinoids extracted from plants has been popular research topic in recent years. China is one of the origins of cannabis and one of the few countries with wild cannabis plants. However, the genetic structure of Chinese cannabis and the degree of adaptive selection remain unclear. Results The main morphological characteristics of wild cannabis in China were assessed. Based on whole-genome resequencing SNPs, Chinese cannabis could be divided into five groups in terms of geographical source and ecotype: wild accessions growing in the northwestern region; wild accessions growing in the northeastern region; cultivated accessions grown for fibre in the northeastern region; cultivated accessions grown for seed in northwestern region, and cultivated accessions in southwestern region. We further identified genes related to flowering time, seed germination, seed size, embryogenesis, growth, and stress responses selected during the process of cannabis domestication. The expression of flowering-related genes under long-day (LD) and short-day (SD) conditions showed that Chinese cultivated cannabis is adapted to different photoperiods through the regulation of Flowering locus T-like (FT-like) expression. Conclusion This study clarifies the genetic structure of Chinese cannabis and offers valuable genomic resources for cannabis breeding.
... Cannabis sativa and Cannabis indica. As stated by Clarke and Merlin (2013) and Small (2015), based on natural origins and associations with humans, taxonomists have recognized three more populations of this plant spp. namely those that are truly wild, those that are cultivated and those that are feral escapes which grow spontaneously in areas associated with and often disturbed by humans. ...
Chapter
Full-text available
Cannabis: The journey from medical to Intoxicant and back again
... All the classes have medicinal cannabinoids compounds, but in different proportions. For instance, Cannabis Sativa has a high level of Cannabidiol (CBD), while C. Indica and Rudelaris have high and low levels of ∆ 9 -tetrahydrocannabinol (THC) respectively [3][4][5]. ...
Article
Full-text available
The traditional Cannabis plant as a medicinal crop has been explored for many thousands of years. The Cannabis industry is rapidly growing; therefore, optimising drying methods and producing high-quality medical products have been a hot topic in recent years. We systemically analysed the current literature and drew a critical summary of the drying methods implemented thus far to preserve the quality of bioactive compounds from medicinal Cannabis. Different drying techniques have been one of the focal points during the post-harvesting operations, as drying preserves these Cannabis products with increased shelf life. We followed or even highlighted the most popular methods used. Drying methods have advanced from traditional hot air and oven drying methods to microwave-assisted hot air drying or freeze-drying. In this review, traditional and modern drying technologies are reviewed. Each technology will have different pros and cons of its own. Moreover, this review outlines the quality of the Cannabis plant component harvested plays a major role in drying efficiency and preserving the chemical constituents. The emergence of medical Cannabis, and cannabinoid research requires optimal post-harvesting processes for different Cannabis strains. We proposed the most suitable method for drying medicinal Cannabis to produce consistent, reliable and potent medicinal Cannabis. In addition, drying temperature, rate of drying, mode and storage conditions after drying influenced the Cannabis component retention and quality
... Cannabis sativa and Cannabis indica. As stated by Clarke and Merlin (2013) and Small (2015), based on natural origins and associations with humans, taxonomists have recognized three more populations of this plant spp. namely those that are truly wild, those that are cultivated and those that are feral escapes which grow spontaneously in areas associated with and often disturbed by humans. ...
Chapter
Full-text available
Role of “Exercise” An Adjunct tool in addiction rehabilitation
... For example, hemp fibre, obtained from the plant stems (i.e., phloem), is traditionally used in the shipbuilding industry and for other purposes. Moreover, female flowers exhibit pharmacological activity, and seeds are used mainly as food (Small, 2015). ...
Article
This study aimed to determine a complete chemical composition of eight different varieties of whole hemp seeds and eight samples of commercial dehulled hemp seeds. We also evaluated the phenolic profiles and antioxidant, cytotoxic, and antimicrobial properties of hydromethanolic seed extracts. Whole hemp seeds contain much more fibre than dehulled hemp seeds, which contain more fat and protein. Sucrose and raffinose were the most abundant soluble sugars, and citric and oxalic acid were the most abundant organic acids. In the hydromethanolic hemp seed extracts, we detected the phenolic acids ferulic acid-hexoside and syringic acid. Whole hemp seed extracts exhibited better antioxidant activity than dehulled hemp seed extracts, especially in the TBARS assay. Cytotoxic activity against NCI-H460 cells was also observed. The dehulled hemp seed extracts displayed antibacterial activity, especially against Bacillus cereus, Listeria monocytogenes, and Enterococcus faecalis, and antifungal activity to a lesser extent.
... Cannabis sativa L. (Cannabaceae) was one of the first non-food crops to be cultivated. It is an annual flowering herbaceous plant native to temperate central Asia, where its use seems to date back to around 4500 BC [1,2]. This species is found in different habitats ranging from sea level to the temperate and alpine foothills of the Himalayas [3]. ...
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The chemical profile of the Cannabis sativa L. female inflorescences is rather complex being characterized by a large number of molecules belonging to different chemical classes. Considering the numerous applications in various fields, including the medical and pharmaceutical sectors, that have seen a large use of Cannabis genus in recent years, a precise characterization of the matrices is essential. In this regard, the application of adequate and suitable sampling and analysis techniques becomes important in order to provide an identification of the metabolites characterizing the profile of the sample under examination. The goal of this work is to provide additional information on the chemical composition of the inflorescences of five C. sativa different cultivars grown in Emilia Romagna (Italy) through the application of sophisticated analysis techniques such as Solid-Phase Microextraction-Gas Chromatography-Mass Spectrometry and Ultra-Performance Liquid Chromatography-Mass Spectrometry (SPME-GC-MS and UPLC-MS). The obtained data highlighted the presence of a high number of volatile and non-volatile compounds, thus allowing a comparative evaluation of the different samples. Furthermore, an in-depth statistical survey by Principal Components Analysis (PCA) and HeatMap, Hierarchical luster Analysis (HCA) and Partial Least Squares Discriminant Analysis (PLS-DA-VIP), was conducted to consider any correlations between the investigated cultivars. The findings of this study may help to provide more information on the C. sativa inflorescences useful for potential applications of their metabolites in scientific research.
... However, numerous cannabis strains have been selected through breeding programs whose chemotaxonomic properties do not correlate with a Cannabis indica or Cannabis sativa lineage (Hillig and Mahlberg, 2004). More recently, the existence of only one species (Cannabis sativa L.), has been proposed (Small, 2015) with the strains categorized according to the content of the cannabinoids trans-Δ 9 -tetrahydrocannabinol (Δ 9 -THC) and cannabidiol (CBD). Δ 9 -THC dominant strains with low CBD content induce intoxicating, psychotropic effects including euphoria, enhancement of sensory perception and impairment in memory. ...
Article
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The medicinal use of Cannabis sativa L. can be traced back thousands of years to ancient China and Egypt. While marijuana has recently shown promise in managing chronic pain and nausea, scientific investigation of cannabis has been restricted due its classification as a schedule 1 controlled substance. A major breakthrough in understanding the pharmacology of cannabis came with the isolation and characterization of the phytocannabinoids trans -Δ ⁹ -tetrahydrocannabinol (Δ ⁹ -THC) and cannabidiol (CBD). This was followed by the cloning of the cannabinoid CB1 and CB2 receptors in the 1990s and the subsequent discovery of the endocannabinoid system. In addition to the major phytocannabinoids, Δ ⁹ -THC and CBD, cannabis produces over 120 other cannabinoids that are referred to as minor and/or rare cannabinoids. These cannabinoids are produced in smaller amounts in the plant and are derived along with Δ ⁹ -THC and CBD from the parent cannabinoid cannabigerolic acid (CBGA). While our current knowledge of minor cannabinoid pharmacology is incomplete, studies demonstrate that they act as agonists and antagonists at multiple targets including CB1 and CB2 receptors, transient receptor potential (TRP) channels, peroxisome proliferator-activated receptors (PPARs), serotonin 5-HT 1a receptors and others. The resulting activation of multiple cell signaling pathways, combined with their putative synergistic activity, provides a mechanistic basis for their therapeutic actions. Initial clinical reports suggest that these cannabinoids may have potential benefits in the treatment of neuropathic pain, neurodegenerative diseases, epilepsy, cancer and skin disorders. This review focuses on the molecular pharmacology of the minor cannabinoids and highlights some important therapeutic uses of the compounds.
... indica (Lam.), and Cannabis sativa ssp. ruderalis (Janisch), although, in some studies, these plants are classified as distinct species [2][3][4]. Cannabis sativa is the most widely spread variety, growing in both tropical and temperate climates. The two main preparations derived from cannabis are marijuana and hashish. ...
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Cannabis (Cannabis sativa L.) plants from the family Cannabidaceae have been used since ancient times, to produce fibers, oil, and for medicinal purposes. Psychoactive delta-9-tetrahydrocannabinol (THC) and nonpsychoactive cannabidiol (CBD) are the main pharmacologically active compounds of Cannabis sativa. These compounds have, for a long time, been under extensive investigation, and their potent antioxidant and inflammatory properties have been reported, although the detailed mechanisms of their actions have not been fully clarified. CB1 receptors are suggested to be responsible for the analgesic effect of THC, while CB2 receptors may account for its immunomodulatory properties. Unlike THC, CBD has a very low affinity for both CB1 and CB2 receptors, and behaves as their negative allosteric modulator. CBD activity, as a CB2 receptor inverse agonist, could be important for CBD anti-inflammatory properties. In this review, we discuss the chemical properties and bioavailability of THC and CBD, their main mechanisms of action, and their role in oxidative stress and inflammation.
... Another study has shown that the C. sativa genotypes with yellow stems exhibit greater mechanical processability than green-stemmed genotypes and contain more bast fibre yield (Musio et al., 2018). Further, late-flowering genotypes have shown a high fibre yield compared with early flowering genotypes (H€ oppner and Menge-Hartmann, 2007;Small, 2015). While dual-purpose or multipurpose genotypes have been produced in hemp-breeding programs (Tang et al., 2016;Papastylianou et al., 2021), there is no clear split between fibre, seed, and phytochemical type male plants (Salentijn et al., 2015), and their potential for fibre production has not been investigated. ...
Article
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Industrial hemp (Cannabis sativa L.) is identified as a leading fibre crop and there is increasing interest in C. sativa fibre due to its new range of industrial applications. However, the complexity of hemp germplasm resulted in insufficient information on the effect of genotypes on fibre quality and quantity. In this study, 16 fibre and non-fibre type hemp genotypes were evaluated to compare the morpho-anatomical differences of stems and physico-mechanical fibre properties under three retting methods and to understand the effect of stem colour on the properties of hemp fibres. Morphological markers were scored and stem anatomy was examined using live and herbarium collections. Stems were retted using chemical, enzymatic, and microbiological methods. The resulting fibres were tested for tensile strength, moisture retention, colour, bast and hurd dry weights. Hemp genotypes showed morphological variations that affect fibre processing and a unique pattern of fibre wedges in cross-sections of the basal internode. Fibre yield, tensile strength, colour, and moisture retention significantly varied among the genotypes. The hemp collection used in this study formed three clusters in principal component analysis and traits such as internodal length, node number, hurd yield, and tensile strength highly contributed to the total variability. Additionally, non-fibre type hemp genotypes that showed important fibre properties were identified. The hemp genotypes that were selected based on our approaches can be tailored towards the specificities of the end-usage of choice. Our methods will enable the exploration of hemp genetic diversity pertaining to fibre properties and contribute to the preliminary identification of genotypes as a supplement to genetic analyses.
... Because of the illegal status of Cannabis, plants were selected for indoor cultivation, growth under artificial light and a highly branched yet small architecture [47,48]. Even after legalization, indoor cultivation remains popular. ...
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Cannabis sativa is most prominent for its psychoactive secondary compound tetrahydrocannabinol, or THC. However, THC is only one of many phytocannabinoids found in this (in)famous medicinal plant. The stepwise legalization of Cannabis in many countries has opened opportunities for its medicinal and commercial use, sparking scientific interest in the genetics and biochemistry of phytocannabinoid synthesis. Advances in plant biology and genomics help to accelerate research in the Cannabis field, which is still lagging behind other comparable high-value crops. Here, we discuss the intriguing genetics and evolutionary history of phytocannabinoid synthases, and also show that an increased understanding of Cannabis developmental genetics and morphology are of critical importance to leverage the full potential of phytocannabinoid production.
... Depending on the environmental conditions and the genetic variety, it can reach up to 5 m (Farag and Kayser 2017). C. sativa preferably grows in wet places and near water bodies (Small 2015) and flowers in the month of July-August (Rana and Datt 1997). ...
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Bhanga (Cannabis) has been reported with numerous therapeutic, traditional, commercial, and sacred uses in India and across the globe. Its uses are deeply rooted in the cultural, social, and economic lives of the people. The inclusion of Cannabis under ‘Scheduled E1’ drugs in India restricts its use. However, being a crop of economic and medicinal importance, the pharmaceutical and various other sectors are showing much interest in the plant. The present review article delineates traditional, culinary, cosmetic, ritual, social, spiritual, recreational, economic, and therapeutic uses of Cannabis. The review illustrates various uses of Cannabis across the globe; noted from articles, publications, and books providing description of various parts, viz. leaves and seeds (Bhanga), flowering and fruiting tops (Ganja), resin (Charas), extract, tincture, and whole plant, stalks (Fibers). The review may be helpful to researchers, clinicians, and pharmaceutical companies to carry out further research for developing cost-effective healthcare options.
... Depending on the environmental conditions and the genetic variety, it can reach up to 5 m (Farag and Kayser 2017). C. sativa preferably grows in wet places and near water bodies (Small 2015) and flowers in the month of July-August (Rana and Datt 1997). ...
... Despite the reliance on clonal propagation, there is a continual need to germinate seeds to select new elite genotypes, perform pheno-hunting, as well as supporting breeding programs. To select new elite genotypes, plants are started from seed (technically achenes [3], but will be referred to as seed henceforth). During the vegetative phase of growth, a cutting is taken and maintained as a vegetative plant while the seedling is grown to maturity. ...
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In vitro seed germination is a useful tool for developing a variety of biotechnologies, but cannabis has presented some challenges in uniformity and germination time, presumably due to the disinfection procedure. Disinfection and subsequent growth are influenced by many factors, such as media pH, temperature, as well as the types and levels of contaminants and disinfectants, which contribute independently and dynamically to system complexity and nonlinearity. Hence, artificial intelligence models are well suited to model and optimize this dynamic system. The current study was aimed to evaluate the effect of different types and concentrations of disinfectants (sodium hypochlorite, hydrogen peroxide) and immersion times on contamination frequency using the generalized regression neural network (GRNN), a powerful artificial neural network (ANN). The GRNN model had high prediction performance (R 2 > 0.91) in both training and testing. Moreover, a genetic algorithm (GA) was subjected to the GRNN to find the optimal type and level of disinfectants and immersion time to determine the best methods for contamination reduction. According to the optimization process, 4.6% sodium hypochlorite along with 0.008% hydrogen peroxide for 16.81 min would result in the best outcomes. The results of a validation experiment demonstrated that this protocol resulted in 0% contamination as predicted, but germination rates were low and sporadic. However, using this sterilization protocol in combination with the scarification of in vitro cannabis seed (seed tip removal) resulted in 0% contamination and 100% seed germination within one week.
... In the past, it was mostly cultivated for fiber and grain, but nowadays, the plant is gaining importance in the medicinal industry due to its production of unique cannabinoids (Andre et al., 2016). They are produced in the trichomes on flower bracts of female inflorescences (Small, 2015;Andre et al., 2016). Most pharmaceutically important cannabinoids are cannabidiol (CBD) and the psychoactive tetrahydrocannabinol (THC) ( -9-THC) (Freeman et al., 2019). ...
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The use of the cannabis plant as a source of therapeutic compounds is gaining great importance since restrictions on its growth and use are gradually reduced throughout the world. Intensification of medical (drug type) cannabis production stimulated breeding activities aimed at developing new, improved cultivars with precisely defined, and stable cannabinoid profiles. The effects of several exogenous substances, known to be involved in sex expressions, such as silver thiosulfate (STS), gibberellic acid (GA), and colloidal silver, were analyzed in this study. Various concentrations were tested within 23 different treatments on two high cannabidiol (CBD) breeding populations. Our results showed that spraying whole plants with STS once is more efficient than the application of STS on shoot tips while spraying plants with 0.01% GA and intensive cutting is ineffective in stimulating the production of male flowers. Additionally, spraying whole plants with colloidal silver was also shown to be effective in the induction of male flowers on female plants, since it produced up to 379 male flowers per plant. The viability and fertility of the induced male flowers were confirmed by fluorescein diacetate (FDA) staining of pollen grains, in vitro and in vivo germination tests of pollen, counting the number of seeds developed after hybridization, and evaluating germination rates of developed seeds. Finally, one established protocol was implemented for crossing selected female plants. The cannabinoid profile of the progeny was compared with the profile of the parental population and an improvement in the biochemical profile of the breeding population was confirmed. The progeny had a higher and more uniform total CBD (tCBD) to total tetrahydrocannabinol (tTHC) ratio (up to 29.6; average 21.33 ± 0.39) compared with the original population (up to 18.8; average 7.83 ± 1.03). This is the first comprehensive report on the induction of fertile male flowers on female plants from dioecious medical cannabis ( Cannabis sativa L.).
... sativa being taller and more highly branched and C. indica being shorter with broader leaves), their original geographic range (C. sativa originated from Europe and C. indica from Asia), and the composition of their secondary metabolites (secondary plant metabolites are large numbers of chemical compounds produced by plant cells, using biosynthetic enzymes and building blocks derived from primary plant metabolic pathways) all showed differences, but the dilemma about their taxonomical separation, whether they are separate species or subspecies, continues to the present day (Russo, 2007;Small, 2015;Pollio, 2016). Several review and research papers have provided detailed reports about the classification and nomenclature of cannabis (Fischedick et al., 2010;Pollio, 2016;McPartland, 2017McPartland, , 2018. ...
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Pain prevalence among adults in the United States has increased 25% over the past two decades, resulting in high health-care costs and impacts to patient quality of life. In the last 30 years, our understanding of pain circuits and (intra)cellular mechanisms has grown exponentially, but this understanding has not yet resulted in improved therapies. Options for pain management are limited. Many analgesics have poor efficacy and are accompanied by severe side effects such as addiction, resulting in a devastating opioid abuse and overdose epidemic. These problems have encouraged scientists to identify novel molecular targets and develop alternative pain therapeutics. Increasing preclinical and clinical evidence suggests that cannabis has several beneficial pharmacological activities, including pain relief. Cannabis sativa contains more than 500 chemical compounds, with two principle phytocannabinoids, Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD). Beyond phytocannabinoids, more than 150 terpenes have been identified in different cannabis chemovars. Although the predominant cannabinoids, Δ9-THC and CBD, are thought to be the primary medicinal compounds, terpenes including the monoterpenes β-myrcene, α-pinene, limonene, and linalool, as well as the sesquiterpenes β-caryophyllene and α-humulene may contribute to many pharmacological properties of cannabis, including anti-inflammatory and antinociceptive effects. The aim of this review is to summarize our current knowledge about terpene compounds in cannabis and to analyze the available scientific evidence for a role of cannabis-derived terpenes in modern pain management. SIGNIFICANCE STATEMENT: Decades of research have improved our knowledge of cannabis polypharmacy and contributing phytochemicals, including terpenes. Reform of the legal status for cannabis possession and increased availability (medicinal and recreational) have resulted in cannabis use to combat the increasing prevalence of pain and may help to address the opioid crisis. Better understanding of the pharmacological effects of cannabis and its active components, including terpenes, may assist in identifying new therapeutic approaches and optimizing the use of cannabis and/or terpenes as analgesic agents.
... Cannabis is sometimes used interchangeably with the term "hemp"; however, the latter only refers to varieties cultivated for non-drug uses. The cannabis plant is widely used for hemp fiber, hemp seeds and oils, hemp leaves for use as vegetables and juices, and as a recreational drug (Small 2015). Medically, cannabis has long been considered of value as a general analgesic, anesthetic, antidepressant, antibiotic, and sedative; its history dates back to 2700 BCE when cannabis was first documented in a Chinese pharmacopeia by Chinese Emperor Shen Nung, who is widely regarded as the Father of Chinese Medicine (Touw 1981;Pisanti and Bifulco 2019). ...
Article
Background: Cannabis refers to a plant in the family Cannabaceae, which has been used medically, recreationally, and industrially. The last two decades, in particular, have seen a large increase in the volume of literature on this topic. The present bibliometric analysis aims to capture the characteristics of scholarly journal publications on the topic of cannabis and cannabinoid research. Methods: Searches were run on the Scopus database on April 02, 2021, as follows "(TITLE (cannabi* OR hashish OR marijuana OR marihuana)) AND ( LIMIT-TO ( DOCTYPE,"ar" ) OR LIMIT-TO ( DOCTYPE,"re" ) )". Results were exported on the same day to prevent discrepancies between daily database updates. Only "article" and "review" publication types were included; no further search limits were applied. The "article" publication type includes publications featuring original research, whereas "review" includes reviews and conference papers. The following data were collected: number of publications (in total and per year), authors, and journals; open access status; publications per journal; journals publishing the highest volume of literature and their impact factors, language of publication; document type; publication country; author affiliations; funding sponsors; most highly cited publications; and most highly published authors. Trends in this subset of publications were identified and presented. Bibliometric networks were constructed using the software tool VOSviewer. Results: A total of 29 802 publications (10 214 open access), published by 65 109 authors, were published in 5474 journals from 1829 to 2021. The greatest number of publications was published over the last 20 years. The journal that published the largest number of publications was Drug and Alcohol Dependence (n = 705). The most productive countries included the USA (n = 12 420), the UK (n = 2236), and Canada (n = 2062); many of the most common institutional affiliations and funding sponsors originated from these countries. Conclusions: The number of publications published on the topic of cannabis follows an upward trend. Over the past 20 years, the volume of cannabis research has grown steeply, which can be attributed to a large amount of funding dedicated to researching this topic. Future research should continue to investigate changes in the publication characteristics of emerging research, as the volume of publications on this topic is expected to rapidly grow.
... The mother plant. However, care should be taken with the prolonged life of the m due to the occurrence of mutations and somaclonal variations that can decl and phytocannabinoid content in clones compared to the original mothe Another option is to carry out seminiferous propagation with feminized seed Although it is practically unanimous among scientists to consider inflorescences as the product of interest for medicinal use [12,13,21], recently published reporting that these structures should be considered as fruits or in considering that the flowers senesce and turn into fruits that, in turn, ripen [3 it should be noted that parthenocarpy consists of the growth of the ovary fruit without the occurrence of pollination [38]. The structures produced by th complex floral structures (such as stigmas) (Figure 1) that support their ide flowers. ...
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The main characteristic of Cannabis sativa L. is the production of compounds of medicinal interest known as phytocannabinoids. Environmental factors and crop management practices are directly related to the yield of these compounds. Knowing how these factors influence the production of phytocannabinoids is essential to promote greater metabolite yield and stability. In this review, we aim to examine current cannabis agronomic research topics to identify the available information and the main gaps that need to be filled in future research. This paper introduces the importance of C. sativa L., approaching state-of-the-art research and evaluating the influence of crop management and environment conditions on yield and phytocannabinoid production, including (i) pruning; (ii) light and plant density; (iii) ontogeny; (iv) temperature, altitude, and CO2 concentration; (v) fertilization and substrate; and (vi) water availability, and presents concluding remarks to shed light on future directions.
... sativa-many different taxonomical divisions of the genus (at the species, subspecies, and varieties level) have been proposed. [17][18][19][20][21][22] At present, the most widely accepted hypothesis is that the genus consists of a single species, C. sativa, with several subspecies, varieties, cultivars, and chemovars. Plants that contain < 0.3% of D 9 -tetrahydrocannabinol (THC) and grown for fiber and seed production are normally called hemp. ...
Article
Background: Despite the benefits that synthetic pesticides have provided in terms of pest and disease control, they cause serious long-term consequences for both the environment and living organisms. Interest in ecofriendly products has subsequently increased in recent years. Methods: This article briefly analyzes the available ethnobotanical evidence regarding the use of Cannabis sativa as a pesticide and offers a systematic review of experimental studies. Results: Our findings indicate that both ethnobotanical and experimental procedures support the use of C. sativa as a pesticide, as remarkable toxicity has been observed against pest organisms. The results included in the systematic review of experimental studies (n = 30) show a high degree of heterogeneity, but certain conclusions can be extracted to guide further research. For instance, promising pesticide properties were reported for most of the groups of species tested, especially Arachnida and Insecta; the efficacy of C. sativa as a pesticide can be derived from a wide variety of compounds that it contains and possible synergistic effects; it is crucial to standardize the phytochemical profile of C. sativa plants used as well as to obtain easily reproducible results; appropriate extraction methods should be explored; and upper inflorescences of the plant may be preferred for the production of the essential oil, but further studies should explore better other parts of the plant. Conclusion: In the coming years, as new findings are produced, the promising potential of C. sativa as a pesticide will be elucidated, and reviews such as the present one constitute useful basic tools to make these processes easier.
... Cannabis sativa L. is a dioecious crop frequently cultivated for its cannabinoids, fibre and seeds [44][45][46][47][48][49][50]. This species is anemophilous, and its exine morphology reflects this dispersal strategy, meaning its pollen grains are not ornamented and thus well suited to rapid movement coinciding with any changes in air flow [51,52]. ...
Article
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Pollen grains are male gametophytes, an ephemeral haploid generation of plants, that commonly engage in competition for a limited supply of ovules. Since variation in reproductive capabilities among male gametophytes may influence the direction and pace of evolution in populations, we must be able to quantify the relative fitness of gametophytes from different sires. To explore this, we estimated the relative fitness of groups of male gametophytes in a dioecious, wind-pollinated model system, Cannabis sativa , by characterizing the non-abortion rate (measured via chemical staining) and viability (measured via in vitro germination) of pollen from multiple sires. Pollen viability quickly declined within two weeks of anther dehiscence, and pollen stored under freezer conditions did not germinate regardless of storage time. In contrast, pollen non-abortion rates declined slowly and persisted longer than the lifetime of a sporophyte plant under both room temperature and freezer conditions. Pollen samples that underwent both viability and non-abortion rate analysis displayed no significant correlation, implying that researchers cannot predict pollen viability from non-abortion rates, nor infer male gametophytic fitness from a single measure. Our work demonstrates two independent, differential approaches to measure proxies of male fitness in C . sativa .
... Cannabis sativa and Cannabis indica. As stated by Clarke and Merlin (2013) and Small (2015), based on natural origins and associations with humans, taxonomists have recognized three more populations of this plant spp. namely those that are truly wild, those that are cultivated and those that are feral escapes which grow spontaneously in areas associated with and often disturbed by humans. ...
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Adverse effects associated with cannabis used for medical Problems
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Cannabis use in the United States is growing at an unprecedented pace. Most states in the United States have legalized medical cannabis use, and many have legalized nonmedical cannabis use. In this setting, health care professionals will increasingly see more patients who have questions about cannabis use, its utility for medical conditions, and the risks of its use. This narrative review provides an overview of the background, pharmacology, therapeutic use, and potential complications of cannabis.
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Due to recent classification as a commodity crop in North America, producer interest in industrial hemp (Cannabis sativa L.) has increased. In the Commonwealth of Virginia, there is a need to evaluate foreign-developed industrial hemp for its adaptability and to develop new cultivars suited to local climatic conditions. Eight cultivars (‘Bialobrzeskie’, ‘Canda’, ‘Fedora 17’, ‘Felina 32’, ‘Joey’, ‘Tygra’, ‘USO 31’, and ‘Wojko’) were evaluated for grain and five (‘Bialobrzeskie’, ‘Carmagnola’, ‘Fedora 17’, ‘Futura 75’, and ‘Wojko’) for vegetative biomass. An experiment carried out at the Virginia State Research and Demonstration (Randolph) farm was laid out in a randomized complete block design with three replications. The results show that cultivars differed in the cumulative growing degree days (CGDD) needed for growth phase transitions, with ‘USO 31’ having an early transition to the reproductive phase. In addition, ‘Fedora 17’ produced greater grain yield and may have the potential for greater performance with better management to improve its adaptability to local conditions. Across cultivars and years, the grain protein content averaged 241 g kg−1 and the mineral elements were at sufficient levels for animal and human nutrition. ‘Carmagnola’ produced greater biomass yield and has the potential for adoption as local fiber cultivar.
Article
Cannabis sativa L., a low-cost, fast-growing herbaceous plant, is seeing a resurgence in widespread cultivation as a result of new policies and product drive. Its biodegradable and environmentally-benign nature coupled with its high specific surface area and three-dimensional hierarchal structure make it an excellent candidate for use as a biomass-derived carbon material for electrochemical power sources. It is proposed that this ‘wonder-crop’ could have an important role in the energy transition by providing high-functioning carbon-based materials for electrochemistry. In this paper, all instances of C. sativa usage in batteries, fuel cells and supercapacitors are discussed with a focus on highlighting the high capacity, rate capability, capacitance, current density and half-wave potential that can be achieved with its utilisation in the field.
Article
Este trabajo se centra en los organismos dedicados al fomento del cáñamo en España durante la dictadura de Primo de Rivera y la II República, a saber, el Comité Oficial del Cáñamo y la Comisión del Cáñamo, respectivamente. La investigación se ha basado, principalmente, en las publicaciones de la Gaceta de Madrid relativas a los mismos. Ambos organismos eran muy similares, pues la mayoría de sus atribuciones coincidían, por lo que no hubo cambios significativos en el fomento del cáñamo con el cambio de régimen. This article focuses on the agencies dedicated to the promotion of hemp in Spain during the Primo de Rivera dictatorship and the Second Republic, respectively named the “Comité Oficial del Cáñamo” and the “Comisión del Cáñamo”. Research for the article is mainly based on the publications stemming from the “Gaceta de Madrid” relating to said agencies. Since most of their responsibilities closely overlapped, the agencies were very similar, meaning promotion of hemp was not greatly affected by the change in regime.
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This article questions how the concepts of terroir and landrace are relevant for the drug cannabis industry at a time when cannabis legalisation and its associated “green rush” pose a growing threat to both the genetic and cultural diversity that is associated with historical small cannabis farming. The article draws on a multidisciplinary approach based on both extensive secondary sources and primary research. A large and detailed definition work first informs what terroir and landrace are and most especially what they have in common, from the typicity of their end products, to how they owe their existence to geographic remoteness and isolation, and to how tradition and change (or modernity) affect their development and conservation. Defining and connecting terroirs and landraces in historical, anthropological, environmental, and of course chemical terms, makes it possible to determine how cannabis terroirs compare with and differ from other terroirs and plants, based on the rare dual qualities of the plant (being both a food and a drug) but also, given the illegality of its cultivation, on the specific territorial characteristics of its production areas, notably their geographic remoteness and isolation, their politico-territorial control deficits, etc. The article concludes that acknowledging and protecting cannabis terroirs and landraces matters because it favours the conservation and the promotion of a biological, cultural, and sensorial diversity that has endured illegality and repression but is now threatened by legalisation.
Article
Hemp (Cannabis sativa L.) seeds has been traditionally used as food and their consumption is increasing nowadays. They have a remarkable nutritional value, but scarce information is available about mineral elements and their bioavailability. The objectives of this study were to determine the mineral element and phytate contents of eight different varieties of whole hemp seeds and commercial hulled hemp seeds. Phosphorus was the most abundant mineral element with higher content in hulled seeds (1.1 g/100 g) than whole seeds, as well as potassium, magnesium, and zinc. Calcium, manganese, and copper contents were higher in whole seeds. Iron content (8 mg/100 g) was similar in whole and hulled seeds; while sodium was below 5 mg/100 g. Phytate was abundant in hemp (especially hulled) seeds (4 g/100 g), and could compromise iron and zinc absorption (phytates/Fe and phytates/Zn molar ratios above 20 and 15, respectively), as well as involve poor phosphorous absorption. These seeds represent a valuable contribution to manganese (>5 mg/100 g) and copper (>1.4 mg/100 g) intake, approaching 100% and 50%, respectively, of daily NRVs, with a serving size of 30 g. Hemp seeds are an apparently excellent source of minerals, although phytates content should be taken into account to properly interpret nutritional claims.
Article
Background Cannabis is the illegal drug most frequently used by Minors in Austria. Due to the gradual decriminalization and legalization that has taken place in many European countries in recent years, the ÖGKJP would like to take a balanced and scientifically based stand on the complex issue of cannabis use and abuse among young people.Methods The authors searched the medline for current studies using searches tailored to each specific subtopic. Furthermore, recognized compendiums were quoted.ResultsWhile occasional recreational use of cannabis in adults with completed brain maturation and no risk profile for mental disorders is likely to be relatively harmless, early initiation of use with regular use and the increasingly available, highly potent cannabis varieties can lead to explicit and sometimes irreversible neurocognitive brain dysfunction.Conclusion Legalisation of cannabis consumption for minors needs to be objected to due to the risks of the expected damage in the area of brain development. At the same time, however, it is important to establish sensible legal regulations in order to be able to adequately counteract the fact that over 30% of all European young people occasionally consume cannabis. We are also clearly recommending to not criminalize cannabis users and provide necessary support to vulnerable and addicted cannabis users.
Article
Cannabis is among the oldest human domesticates and has been subjected to intensive artificial (human-mediated) selection throughout history to create a wide array of varieties and biotypes for diverse uses, including fiber, food, biofuel, medicine and drugs. This paper briefly reviews the available literature on the taxonomy, evolutionary origin and domestication of this plant, as well as its worldwide dispersal, in both its wild and cultivated forms. Emphasis is placed on Europe and especially on the Iberian Peninsula. Today, it is accepted that Cannabis is a monospecific genus with two subspecies, C. sativa subsp. sativa and C. sativa subsp. indica, originating in Europe and Asia, respectively, by allopatric differentiation after geographic isolation fostered by Pleistocene glacial-interglacial cycles. Palynological and phylogeographic evidence situates the Cannabis ancestor on the NE Tibetan Plateau during the mid-Oligocene. The timing and place of domestication is still a matter of debate between contrasting views that defend single or multiple Neolithic domestication centers situated in different parts of the Eurasian supercontinent, notably central/southeastern China and the Caucasus region. Recent meta-analyses have suggested that wild Cannabis may have already been spread across Europe in the Pleistocene, and its domestication could have occurred during the European Copper/Bronze ages. According to the available reviews and meta-analyses, pre-anthropic dispersal of Cannabis into the Iberian Peninsula seems to have occurred only in postglacial times, and the earlier signs of cultivation date to the Early Medieval Ages. However, the palynological and archaeological evidence used to date is insufficient for a sound assessment, and the development of thorough Iberian databases to address further meta-analysis is essential for more robust conclusions. Some clues are provided for these achievements to be fulfilled.
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One of the key drivers of the alarming increase in anthropogenic carbon emissions is the construction industry and the built environment. Conventional building materials are harmful to the planet because of non-renewable resources and energy-intensive manufacturing processes. Conventional insulation materials, masonry materials, and concrete are highly polluting and cause significant amounts of damage to the global environment. Researchers have recently started studying natural alternatives to overcome the current materials’ environmental challenges and functional disadvantages. Hemp has emerged as a resource with immense potential because of its renewability, ease of cultivation, and low maintenance as an agricultural crop. Many applications of hemp were also found in ancient and modern history before it was replaced with petroleum-based products that were easy and faster to produce. Also, it has found renewed interest amongst the scientific community because of its beneficial properties such as tensile strength, thermal insulation, and lightweight. Many new applications have emerged, such as insulation mats, fiber-reinforced cement concrete, walling material, polymer composites, boards, etc. This chapter synthesizes the research on hemp’s construction applications, namely, hemp insulation mats, hemp fiber-reinforced concrete, and hemp concrete.
Chapter
Industrial hemp (Cannabis sativa L.) has considerable potential as a sustainable crop for numerous existing industrial and consumer products, with many more likely still to be realized. Much early excitement about this ancient crop arose from its assumed capacity to supply renewable feedstocks (e.g., fibers, grain, biomolecules) for numerous uses, both with little environmental “footprint” and the ability to be recycled or upcycled. Although many tout hemp as the solution for all things, such enthusiasm should be tempered by issues of historical precedent and of scale. First, the lack of research investment during the decades-long restriction in the West ensures that time will be needed to develop sustainable hemp production systems. Even as these systems are developed, there are questions about the capacity to grow sufficient amounts of hemp to meet the needs for an array—and large volume—of products. Still, there is room for guarded optimism that as the crop comes “on line,” it will receive the research needed to make the plant a viable resource for farmers and society. This review explores hemp sustainability issues in agronomic and systems contexts and touches on some of the attendant challenges to scale-up.
Chapter
The unbalanced ecological system is expecting the safe and economical solution to recover the safe environment towards the people of next generation because of increasing challenges in pollution control measures and recycling of end components and parts of an automotive, aviation, construction, and textile and toys industries. The exact methodology and its solution may develop a biodegradable and recyclable components and parts especially in various manufacturing sectors also, which leads to develop safe environments. The more usages of natural materials/fibers in fabrication of composites have lead towards the minimizing the carbon footprint and emission of greenhouse gases of composite materials. In recent years, the engineers and researchers have been focusing their investigation towards the solutions to rectify such issues by developing green composites. Nowadays, the green composites have been developed by using the natural fibers, especially from the end part of agriculture corps and tropical plants cultivation processes. In this chapter, a critical assessment deeply carried on the historical background, fibers extraction processes, physical properties, chemical constituents, surface modification and laminate fabrication processes of hemp fibers reinforced composites.
Article
Cannabis use is increasingly common, and with a growing number of jurisdictions implementing legalization frameworks, it is likely that providers will encounter more patients who use cannabis. Therefore, it is important for providers to understand the implications of cannabis use and practical considerations for the perioperative period. Cannabis affects multiple organ systems and may influence intraoperative anesthesia, as well as postoperative pain management. The effects of cannabis and key anesthetic considerations are reviewed here.
Chapter
Life cycle assessment (LCA) is a common tool to evaluate the life cycle environmental impact of products and processes. In the field of polymer composites, due to the ever growing environmental concerns, plant fibers such as flax, hemp, jute, kenaf, bamboo, coir, etc., have received great attention from researchers and industry worldwide, to replace traditional reinforcing fibers for polymer composite products. Plant fiber reinforced composites (PFRCs) have now become competitive engineering materials to partially or even fully replace traditional synthetic fiber based polymer composites, for example, glass fiber reinforced polymers (GFRP), and carbon fiber reinforced polymers (CFRP), and in many cases, PFRCs have been successfully industrially implemented such as in the automotive and sports industry. This chapter will discuss about the concept of LCA and the environmental impacts of PFRCs.
Chapter
The present article provides a concise summary of the research works covered in various areas of natural fibers, polymer matrix, and different techniques performed to enhance the properties of the composites, especially the interfacial properties. The discussion includes various composite manufacturing techniques with the optimum fabrication parameters resulted from the vast literatures in recent years. The mechanical properties such as tensile, flexural, fracture toughness, dynamic mechanical analysis, and thermogravimetric analysis studies are also presented in the discussion. Additionally, a brief review on natural fibers, their structure, mechanical properties, morphology, significant results from literatures emphasizing on the matrix and fiber modification techniques are also covered. The significance of the fiber matrix adhesion is discussed in detail focusing on the interface and interlaminar fracture behaviors along with the prospects for future advances.
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Hemp (Cannabis sativa L.) synthesizes and accumulates a number of secondary metabolites such as terpenes and cannabinoids. They are mostly deposited as resin into the glandular trichomes occurring on the leaves and, to a major extent, on the flower bracts. In the last few years, hemp for production of high-value chemicals became a major commodity in the U.S. and across the world. The hypothesis was that hemp biomass valorization can be achieved through distillation and procurement of two high-value products: the essential oil (EO) and cannabinoids. Furthermore, the secondary hypothesis was that the distillation process will decarboxylate cannabinoids hence improving cannabinoid composition of extracted hemp biomass. Therefore, this study elucidated the effect of steam distillation on changes in the content and compositional profile of cannabinoids in the extracted biomass. Certified organic CBD-hemp strains (chemovars, varieties) Red Bordeaux, Cherry Wine and Umpqua (flowers and some upper leaves) and a T&H strain that included chopped whole-plant biomass, were subjected to steam distillation, and the EO and cannabinoids profile were analyzed by gas chromatography-mass spectrometry (GC–MS) and HPLC, respectively. The distillation of hemp resulted in apparent decarboxylation and conversion of cannabinoids in the distilled biomass. The study demonstrated a simple method for valorization of CBD-hemp through the production of two high-value chemicals, i.e. EO and cannabinoids with improved profile through the conversion of cannabidiolic acid (CBD-A) into cannabidiol (CBD), cannabichromenic acid (CBC-A) into cannabichromene (CBC), cannabidivarinic acid (CBDV-A) into cannabidivarin (CBDV), cannabigerolic acid (CBG-A) into cannabigerol (CBG), and δ-9-tetrahydrocannabinolic acid (THC-A) into δ-9-tetrahydrocannabinol (THC). In addition, the distilled biomass contained CBN while the non-distilled did not. Distillation improved the cannabinoids profile; e.g. the distilled hemp biomass had 3.4 times higher CBD in variety Red Bordeaux, 5.6 times in Cherry Wine, 9 times in variety Umpqua, and 6 times in T&H compared to the original non-distilled samples, respectively. Most of the cannabinoids remained in the distilled biomass and small amounts of CBD were transferred to the EO. The CBD concentration in the EO was as follows: 5.3% in the EO of Umpqua, 0.15% in the EO of Cherry Wine and Red Bordeaux and 0.06% in the EO of T&H. The main 3 EO constituents were similar but in different ratio; myrcene (23.2%), (E)-caryophyllene (16.7%) and selina-3,7(11)-diene (9.6%) in Cherry Wine; (E)-caryophyllene (~ 20%), myrcene (16.6%), selina-3,7(11)-diene (9.6%), α-humulene (8.0%) in Red Bordeaux; (E)-caryophyllene (18.2%) guaiol (7.0%), 10-epi-γ-eudesmol (6.9%) in Umpqua; and (E)-caryophyllene (30.5%), α-humulene (9.1%), and (E)-α-bisabolene (6.5%) in T&H. In addition, distillation reduced total THC in the distilled biomass. Scanning electron microscopy (SEM) analyses revealed that most of the glandular trichomes in the distilled biomass were not disturbed (remained intact); that suggest a possibility for terpenes evaporation through the epidermal membrane covering the glandular trichomes leaving the cannabinoids in the trichomes. This explained the fact that distillation resulted in terpene extraction while the cannabinoids remained in the distilled material.
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For centuries the subject of hemp (Cannabis sativa) has been shrouded in myth and misconceptions, varying from absurd adulation to zealous condemnation. In the last few years the remarkable swell of interest in and use of the plant has been reflected in a rash of topical books about it. Very little has been done, however, to describe the long and worldwide history of man's use of hemp--not only as a euphoric, but as a fiber, an oil, and a medicine--and it is to this neglected aspect that Mr. Merlin devotes his study. The book opens with a look at the botanical aspects of the hemp plant, including a short discussion of its place in the ecology and the natural factors contributing to its geographical dispersal. Mr. Merlin then suggests some historical bases for the use of marijuana in various traditional societies, and concludes by tracing the cultural diffusion of hemp throughout many European and Asian communities. This well-researched and concise study is a welcome needed addition to the growing literature on a controversial subject.
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Cannabis: Evolution and Ethnobotany is a comprehensive, interdisciplinary exploration of the natural origins and early evolution of this famous plant, highlighting its historic role in the development of human societies. Cannabis has long been prized for the strong and durable fiber in its stalks, its edible and oil-rich seeds, and the psychoactive and medicinal compounds produced by its female flowers. The culturally valuable and often irreplaceable goods derived from cannabis deeply influenced the commercial, medical, ritual, and religious practices of cultures throughout the ages, and human desire for these commodities directed the evolution of the plant toward its contemporary varieties. As interest in cannabis grows and public debate over its many uses rises, this book will help us understand why humanity continues to rely on this plant and adapts it to suit our needs.
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We propose the adoption of the word cultigen to designate plants whose origin or selection is primarily due to intentional human activity. The word would be useful in general discourse about "wild" and "cultivated" plants and would clarify the respective scope, terminology and concepts of the International Code of Botanical Nomenclature (ICBN) and the International Code of Nomenclature for Cultivated Plants ICNCP. Associated with this proposal is the possibility of making the distinction between these two kinds of plants explicit through their names.
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Prior to publication of the first edition of the International Code of Nomenclature of Cultivated Plants (ICNCP) some 50 years ago, the only rules governing the naming of cultivated plants were those that also dealt with plants in the wild, the forerunners of the present International Code of Botanical Nomenclature (ICBN). Even today, the Preamble to the ICBN states that its "rules and recommendations apply to all organisms traditionally treated as plants", but also goes on to say that the ICNCP "deals with the use and formation of names for special plant categories in agricultural, forestry, and horticultural nomenclature." The need for the ICNCP and the way in which the two Codes interact are addressed. The progressive independence of plant nomenclature from taxonomy, the theory and practice of classification, is outlined from Linnaeus's development of the binomial to the adoption of the type method. In general, the ICBN makes no assumptions as to the methods, principles or purposes of taxonomy, save one, that the units of taxonomy, the taxa being named, are in some way nested in a hierarchy of ranks. Variation at and below the species level, whether in wild or cultivated plants, is not readily accommodated in a hierarchical structure. On the other hand, the need to communicate and hence name the enormous diversity of cultivated plants at such levels is manifest. The ICNCP provides the rules by which this can be achieved. Cultivated plants fall under the provisions of the ICBN in so far, but only in so far, as they fall within the general system of classification of plants; beyond that the provisions of the ICNCP, which do not require an extensive and obligatory hierarchy of entities, and do not presume that desirable groupings are necessarily non-overlapping, apply.
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This comprehensive volume provides the scientific basis for assessing the likelihood of gene flow between twenty important crops and their wild relatives. The crops discussed include both major staples and minor crops that are nonetheless critical to food security, including barley, corn, cotton, cowpea, wheat, pearl millet, and rice. Each chapter is devoted to one of the crops and details crop-specific information as well as relevant factors for assessing the probability of gene flow. The crop-specific reviews provide insights into the possible ecological implications of gene escape. For each crop, a full-color world map shows the modeled distributions of crops and wild relatives. These maps offer readers, at a glance, a means of evaluating areas of possible gene flow. The authors classify the areas of overlap into three "gene-flow categories" with respect to the possibility of genetic exchange. The systematic, unbiased findings provided here will promote well-informed decision making and the conservation of wild relatives of crops. This book is particularly relevant to agriculture in developing countries, where most crop biodiversity is found and where current knowledge on biodiversity conservation is limited. Given the ecological concerns associated with genetically modified crops, this reference is an essential tool for everyone working to feed a growing world population while preserving crop biodiversity
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Fourteen US states have amended their longstanding, effect-based DUI drug laws to per se or zero tolerant per se statutes in regard to cannabis. Other states are considering enacting similar legislation. Under these amended traffic safety laws, it is a criminal violation for one to operate a motor vehicle with trace levels of cannabinoids or their metabolites in his or her blood or urine. Opponents of per se cannabinoid limits argue that neither the presence of cannabinoids nor their metabolites are appropriate or consistent predictors of behavioral or psychomotor impairment. They further argue that the imposition of such per se limits may result in the criminal conviction of individuals who may have previously consumed cannabis at some unspecified point in time, but were no longer under its influence. As more states enact statutory changes allowing for the legal use of cannabis under certain circumstances, there is a growing need to reexamine the appropriateness of these proposed per se standards for cannabinoids and their metabolites because the imposition of such limits may, in some instances, inadvertently criminalize behavior that poses no threat to traffic safety, such as the state-sanctioned private consumption of cannabis by adults.
Article
It is well known that United States paper currency in general circulation is contaminated with trace amounts of illicit substances such as cocaine, heroin and marijuana. As is the case with cocaine, differentiating "background levels" of the various cannabinoid constituents of Cannabis sativa L., namely, Delta(9)-tetrahydrocannabinol (THC), cannabinol (CBN), and cannabidiol (CBD) contaminating currency found in the general circulation from currency associated with illegal drug activity is imperative if a legal nexus is to be established with the latter. We analyzed 165 randomly collected paper currency notes from 12 U.S. cities (N = 125) and 4 foreign countries (N = 40) for THC, CBD, CBN, 11-nor-9-carboxy-Delta(9)-tetrahydrocannabinol, and 11-hydroxy-Delta(9)-tetrahydrocannabinol. Uncirculated US 1 dollar notes were added as negative controls. Drug residues were washed from individual bills, extracted using a liquid-liquid extraction protocol, derivatized, and quantitated by gas chromatography-mass spectrometry by selected ion monitoring. For the US 1 dollar currency, THC was present in 1.6% (2 notes), CBN 10.31% (13 notes), CBD 1.6% (2 notes). The following concentrations were determined: 0.085 microg/bill and 0.146 microg/bill for THC; 0.014-0.774 microg/bill (mean 0.166 microg/bill) for CBN; and 0.032 microg/bill and 0.086 microg/bill for CBD. For the foreign currency (Colombia, Qatar, India, and New Zealand), THC and CBN were present in 22.5% (9 notes). The following concentration ranges were determined: THC 0.026-0.065 microg/bill (mean 0.049 microg/bill), CBN 0.061-0.197 microg/bill (mean 0.115 microg/bill). All of the positive THC and CBN were found in the New Zealand polypropylene notes. This study demonstrated that marijuana (cannabinoids) may contaminate both paper and plastic currency.
Article
This book presents an historical account of the origins and development of plant and animal domestication across the world, from prehistory to the present day. The formation of basic agricultural systems are described, and the way these systems have been modified in recent times are illustrated. Evidence presented is based upon archaeology, botany, genetics, ecology, and anthropology of domesticates and their wild relatives. Individual chapters present archaeological evidence and reconstruct development of agricultural systems for the broad geographical regions: the Near East, Africa, Far East, and the Americas. Traditional agricultural practice techniques are described. In the final chapter the present situation is reviewed, and the possible risks to a system that now relies on a relatively small number of species to supply the majority of food are discussed. -from Publisher
Book
Professor John Harper, in his recent Population Biology of Plants (1977), made a comment and asked a question which effectively states the theme of this book. Noting that 'one of the consequences of the development of the theory of vegetational climax has been to guide the observer's mind forwards', i. e. that 'vegetation is interpreted as a stage on the way to something', he commented that 'it might be more healthy and scientifically more sound to look more often backwards and search for the explanation of the present in the past, to explain systems in relation to their history rather than their goal'. He went on to contrast the 'disaster theory' of plant succession, which holds that communities are a response to the effects of past disasters, with the 'climax theory', that they are stages in the approach to a climax state, and then asked 'do we account most completely for the characteristics of a population by a knowledge of its history or of its destiny?' Had this question been put to R. S. Adamson, E. J. Salisbury, A. G. Tansley or A. S. Watt, who are amongst the giants of the first forty years of woodland ecology in Britain, their answer would surely have been that understanding lies in a knowledge of destiny. Whilst not unaware of the historical facts of British woodlands, they were preoccupied with ideas of natural succession and climax, and tended to interpret their observations in these terms.
Book
Alphonse de Candolle (1806-93) was a French-Swiss botanist who was an important figure in the study of the origins of plants and the reasons for their geographic distribution. He also created the first Code of Botanical Nomenclature. Despite initially studying law, he took over both the chair of botany at the University of Geneva, and the directorship of Geneva's botanical gardens from his father Augustin de Candolle (1778-1841). He published numerous botanical books, and edited ten volumes of the Prodromus, a seventeen-volume reference text intended to cover the key properties of all known seed plants. This work, reissued in the second edition of the English translation of 1886, is his most famous and influential book, tracing the geographic origins of plants known to have been cultivated by humans. It is one of the earliest studies of the history of crop domestication, and an important contribution to phytogeography.
Article
In an effort to reduce the overproduction of a too limited number of arable food crops, several research programs focusing on industrial crops have recently been initiated in the Netherlands. The 'Hemp research program' investigated from 1990 to 1994, the feasibility of hemp as an arable crop and as a raw material for paper pulp. In this context, breeding, agronomy, plant pathology, mechanization, processing and economics were the subject of a comprehensive study.This thesis reports on a part of the breeding research. A collection of Cannabis germplasm, covering variation within the genus, was established and evaluated at the DLO-Centre for Plant Breeding and Reproduction Research (CPRO-DLO, Wageningen). Stem production, stem quality, psychoactive potency and resistance to soil pathogens were considered relevant criteria for the introduction of hemp in crop rotations in the Netherlands and its utilization as a raw material for paper pulp. Prospects for the breeding of improved cultivars were based on the diversity for these traits, their stability, and mutual relations.In its final state the established germplasm collection comprised ca. 200 accessions (entries, populations), including fibre strains, drug strains, an ornamental cultivar and truly wild or naturalized populations (Chapter 2). According to consulted references, considerable mutual relatedness seemed to exist among fibre cultivars. Italian and German strains, especially, have directly been the basis of, or have been used as breeding parents for many of the present cultivars. Also, the central European naturalized populations and the fibre landraces seemed quite closely related to modern fibre cultivars. The drug strains were expected to be more distinct. The collection was considered to be sufficiently representative for investigating diversity in Cannabis.Traits related to stem production, stem quality and psychoactive potency were observed for ca. 160 accessions in field trials, or determined afterwards with field grown materials. Trials were carried out at CPRO (52° N latitude). Accessions were grown in small plots in two replicates, in high plant density to obtain results that are readily interpretable for fibre hemp cultivation. Host reactions to the root-knot nematode Meloidogyne hapla Chitwood were assessed for ca. 150 accessions in a seedling test, and verified in a field trial for a subset of accessions.Variation in phenological development and in stem elongation was studied in relation to stem production (Chapter 3). Large variation among accessions was found for the day of anthesis (ranging from approximately 10 May to 30 September) and consequently for the day of seed maturity. A higher latitude of origin was associated with earlier anthesis and seed maturity (r=-0.75). The phenological pattern was stable over years. Stem elongation was characterized by the parameters of a sigmoid curve fitted to periodical measurements of stem length. Significant differences among accessions were found for these parameters. The final stem length ranged from 60 to 360 cm. Stem elongation was less stable over years than the phenological pattern. Day of anthesis and final stem length were strongly and positively related to stem dry matter production (r>0.7). Some very lateflowering fibre landraces, with low bark fibre contents, produced up to 2200 g of stem dry matter per m 2and exceeded the fibre cultivars (producing 800 to 1750 g/m 2) in stem yield. Late-flowering drug strains were less persistent in a dense crop than late fibre strains. It was concluded that in an efficient crop growth system, seed reproduction and stem production should occur in separate geographic areas. Seed reproduction (adaptation) should be organized at lower latitude to obtain late-flowering, high yielding cultivars for stem production at higher latitude. At a given phenological pattern, breeding can contribute to yield potential by increasing both the persistency of cultivars and the efficiency of stem dry matter accumulation.The large differences between bark tissue and woody core in anatomical and chemical properties, make a quantification of these two fractions important for stem quality assessment. The bark is the most valuable component for pulp production. Accuracy and power of discernment of current procedures for the analysis of the composition of hemp stems were evaluated (Chapter 4). A method using stem segments, intended to reduce the amount of material to be handled, gave somewhat less accurate, but still usable information, than analysis of entire stems. The relation was studied between the simple estimation of the fractions of bark fibre and woody core, commonly applied in fibre hemp breeding, and the assessment of potential pulp recovery according to a more laborious standard method of the pulp and paper industry. The recovery of bark in the pulping process (pulp yield) is accurately predicted by the fraction of bark fibre. The woody core recovered as pulp is a fixed fraction (ca. 69%) of the intact woody core.Variation among accessions was assessed for the woody core fraction in the stem dry weight, which ranged from 50 to 78% (Chapter 5). The fraction of bark, being the complementary tissue, ranged hence from 22 to 50%. The fraction of primary bark fibre in the stem varied from 8 to 27%, the secondary bark fibre from 0 to 14%, and the total bark fibre from 9 to 34%. The fibre cultivars had strongly increased fractions of bark tissue and primary and secondary bark fibre, and reduced fractions of woody core in comparison to wild populations, drug strains and fibre landraces. The levels of the assessed stem fractions were stable over years. Since woody core fibres of hemp are on average too short (550 μm according to references) to produce high quality paper pulp, the evaluation was directed at detecting variation for wood fibre dimensions as well. Accession means for wood fibre length ranged only from 433 to 613 μm. Also the variation within accessions was limited. Breeding for improved woody core quality is considered not very promising. The best strategy for genetic improvement of pulping quality seems a continued selection for increased bark fibre content in fibre cultivars, which implies a reduction of the woody core fraction.A simple possibility to increase bark fibre yield for pulp production is indicated in Chapter 9. It consists of the adaptation of current, well performing fibre cultivars to low latitude, meanwhile maintaining the high bark fibre content by a mild selection. The resulting delay in phenological development is expected to increase the potential bark fibre yield.Large variation among accessions was found for the contents of the major cannabinoids delta-9- tetrahydrocannabinol (THC; 0.01 to 1.77% in the female inflorescence dry matter) and cannabidiol (CBD; 0.05 to 2.19%) (Chapter 6). THC is the psychoactive compound in Cannabis. Within accessions, THC content was less variable than CBD content. Both contents were strongly affected by the year of cultivation, but THC content was more stable than CBD content. Accessions were classified into the phenotypes 'drug', 'intermediate' and 'non-drug' on the basis of cannabinoid profiles. There were no strict relationships between the cannabinoid profiles and nonchemical traits. A few accessions combined for example a considerable psychoactive potency and a high content of bark fibre. On the accession average level, relatively wide leaflets and slow phenological development were weakly associated with a stronger psychoactive potency. There seems little need for efforts aimed at a further reduction of THC content in the current fibre cultivars. The collection comprised a number of accessions, suitable for the selection of genotypes for the production of either THC or CBD.Inoculation of Cannabis seedlings with a larval suspension of the root-knot nematode Meloidogyne hapla, resulted in significant variation for the number of galls and egg masses on the seedling roots (Chapter 7). These parameters were considered as estimates for nematode infection and larval multiplication, respectively. A subset of the tested accessions was grown on a naturally infested arable field to verify the relation between the test results and host reactions in the field. The ranking order of accessions for the seedling test parameters agreed satisfactory with that for nematode infection and multiplication in the field. The collection comprised one relatively resistant fibre cultivar with good agronomic properties which seemed a useful source for further selection. Some highly resistant individual Plants retained from accessions with poor agronomic properties were expected to be useful for cross-breeding.The diversity for the observed agronomic and morphological traits considered together was studied in Chapter 8. Mutual associations among traits were weak, indicating that many combinations of character states within the observed ranges can be established through breeding. For the interpretation of diversity patterns, accessions were grouped a priori on the basis of the presumed purpose and status of domestication resulting in the recognition of four 'plant-use groups': fibre cultivars, fibre landraces, drug strains, and truly wild or naturalized populations. Plant-use groups could be discriminated quite well on the basis of experimental observations. Contents of bark fibre and cannabinoids were most discriminative.A genetic characterization of accessions was additionally attempted on the basis of electrophoretic patterns of seed proteins. Although reproducible variation in banding patterns was found among accessions, the results were quite unsatisfactory as they did not reflect expected common ancestry. Furthermore, the banding patterns were independent from any grouping based on origin or agronomic and morphological traits.Individual accessions suitable for cultivation and breeding are identified in Chapter 9. Issues requiring further evaluation in case of actual hemp breeding and cultivation in the Netherlands are, resistance to the root- lesion nematode Pratylenchus penetrans Cobb and the fungus Botrytis cinerea Pers. ex Fr. (grey mold). Also genetic relationships among accessions need further clarification.
Article
Cannabis sativa has been cultivated for millennia in Eurasia and for centuries in North America, as a source of a textile fibre, oilseed, and intoxicating drugs such as marijuana. Considerable literature is available on the agricultural and biological properties of these basic three cultigens, but relatively little is published on wild-growing plants of the species. Most weedy C. sativa differ from the cultigens in a number of ecological properties, particularly with regard to reproductive biology. The species is the classical example of a "camp follower" that is exceptionally adapted to the habitat conditions around settlements: rich, highly manured, moist soils, and open areas resulting from recent removal or disturbance of the vegetation. In Canada, spontaneous populations have been found in all provinces, but forms that have re-evolved wild adaptations are concentrated along the St. Lawrence and lower Great Lakes. The ruderal plants pose a minor weed problem to agriculture but a major problem to law enforcement, and decades of eradication have exterminated many of the naturalized populations in Canada. With the recent re-authorization of hemp cultivation in Canada, it is inevitable that there will be additional escapes and a reinvigoration of the ruderal phase of the species. Mechanical eradication for 2 or 3 yr is effective at destroying populations, and young plants are easily eliminated by herbicide applications.
Article
Most tetrahydrocannabinol (THC) of Cannabis sativa is located in the resin heads of capitate-stalked glandular trichomes. We found that after harvest the resin heads shrink in diameter in exponential decay fashion under ambient room conditions, losing about 15 % in the first month, rising to 24 % over the first year, 32 % by 50 years, and 34 % after a century. An equation accounting for the asymptotic curve descriptive of the progression of shrinkage was determined [original gland head diameter in microns = observed diameter divided by (0.5255 + 0.4745 multiplied by time in days to the power −0.1185)], so that if the age of a specimen is known, the original diameter of the gland heads in the fresh state can be extrapolated. This equation was employed to compare gland head size in samples of different ages. A sample of high-THC medical marijuana strains marketed under license possessed resin head diameters averaging 129 μm, while a sample of low-THC industrial hemp cultivars possessed gland head diameters averaging 80 μm. The mean volume of the resin heads of the narcotic strains was more than four times larger than that of the industrial hemp strains. This is the first documented report of a consistent morphological separator of elite narcotic strains and non-narcotic plants. Most recognized strains of marijuana were bred clandestinely and illicitly during the last half century. The occurrence of large resin gland heads in a sample of officially marketed pharmaceutical strains is an obvious correlate of selection for higher quantity of resin production.
Article
This book presents an historical account of the origins and development of plant and animal domestication across the world, from prehistory to the present day. The formation of basic agricultural systems are described, and the way these systems have been modified in recent times are illustrated. Evidence presented is based upon archaeology, botany, genetics, ecology, and anthropology of domesticates and their wild relatives. Individual chapters present archaeological evidence and reconstruct development of agricultural systems for the broad geographical regions: the Near East, Africa, Far East, and the Americas. Traditional agricultural practice techniques are described. In the final chapter the present situation is reviewed, and the possible risks to a system that now relies on a relatively small number of species to supply the majority of food are discussed. -from Publisher
Article
The classification of plants at infraspecific level is often difficult - variation can be continuous, making a traditional hierarchical classification difficult to maintain. In particular, cultivated plants may require special artificial systems of classification, to conform to the practical needs of breeders. This volume explores the limitations of the present systems, and considers the development of more workable systems in the future.
Article
Variation in Cannabis is evaluated in the context of the confusing systematic history of this genus. Aside from some experimentally produced polyploids, all Cannabis is diploid (n = 10), and there appear to be no barriers to successful hybridization within the genus. The present pattern of variation is due in large part to the influence of man. Two widespread classes of plant are discernible: a group of generally northern plants of relatively limited intoxicant potential, influenced particularly by selection for fibre and oil agronomic qualities, and a group of generally southern plants of considerable intoxicant potential, influenced particularly by selection for inebriant qualities. These two groups are treated respectively as subsp. sativa and indica, of C. sativa, the only species of the genus Cannabis. Within each subspecies two parallel phases are recognizable. The "wild" (weedy, naturalized or indigenous) phase is more or less distinguishable from the domesticated (cultivated or spontaneous) phase by means of an adaptive syndrome of fruit characteristics. The resulting four discernible groups are recognized as varieties.
Article
Two thousand five hundred plants, representing 232 diverse populations of Cannabis, were grown under standard conditions in a garden, scored for 47 attributes, and the data used in a numerical taxonomic study of variation. Groups of interest included "nonintoxicant" and "semi-intoxicant" populations (collectively referable to C. sativa), "intoxicant" populations (sometimes called C. indica), fiber and oil cultivars (referable to C. sativa), "wild" populations (sometimes called C. ruderalis), and plants either containing or not containing cannabigerol monomethyl ether. Clustering methodology revealed only a limited tendency for the populations to separate into the above groupings. However, canonical analysis (equally weighted multiple discriminant analysis) of morphological characteristics only proved highly successful in delineating the groups. The analysis resulting from the comparison of wild and cultivated populations when applied to a large sample of populations failed to suggest two discrete groupings, and it is consequently concluded that wild and cultivated populations intergrade so greatly as to preclude recognition of wild plants as a separate species (the so-called C. ruderalis). Those morphological characteristics that successfully distinguish intoxicant populations from other populations in material raised under standardized garden conditions were sufficiently variable to suggest that the intoxicant potential of plants collected in nature cannot be reliably distinguished by morphology; consequently it is judged that there are no grounds for distinguishing intoxicant plants (the so-called C. indica) as a separate species. It is concluded that all plants of Cannabis are assignable to one species, C. sativa.
Article
A dioecious plant, Cannabis sativa has two sex chromosomes (X and Y). The genome sizes of the diploid female and male plants were determined to be 1636 and 1683 Mbp, respectively, by flow cytometry. By the karyotype analysis, the X and Y chromosomes were found to be submetacentric and subtelocentric, respectively. The Y chromosome had the largest long arm with a satellite in the terminal of its short arm. Conspicuous condensation was specifically observed in the long arm and satellite of the Y chromosome during the prometaphase to metaphase stages. These results indicate that the Y chromosome, especially in its long arm, specifically differentiates in Cannabis sativa and might contribute to the sex determination.
Article
Naturalized populations of hemp (Cannabis sativa L.) on a range of sites in E-central Illinois were intensively studied. Fifty-one independent (site) and 26 dependent (plant) parameters were quantified from 101 randomly selected stands. All site variables that could be quantified were examined statistically. These included soil physical and chemical properties, competition, physical site characteristics and stand histories. Correlations between dependent parameters and linear relationships between dependent and independent parameters were examined prior to multiple correlation analysis of each dependent variable. Extreme variation was found in most dependent variables. In only a few instances could a significant portion of the variance in a dependent variable be partitioned by multiple regression. Regression did permit an evaluation of the relative importance of each specific independent variable to any given dependent variable and to the overall ecology of hemp. Those parameters were particularly important that influenced seed production in this annual plant whose seeds do not long retain viability in the soil. Important parameters that influenced seed production were interspecific competition, especially from grasses, exposure to sunlight, soil disturbance the previous year, soil aeration and available phosphorus and potassium. Viable seed production ranged from 0 to 34,433 per sq m, with a mean of 4555. Two important agents effected some degree of biological control. Alternaria alternata (Fr.) Keissler, a common fungal pathogen of many plants, destroyed an average of 20.5% of developing seeds, while larvae of Grapholitha tristrigana Clements (Lepidoptera: Tortricidae) destroyed 7.1%. Although a few stands had no damage by the insect, every stand suffered attack from the fungus which destroyed up to 45.5% of seeds in extreme cases.
Article
Though there is no absolute distinction between the systematics of wild and cultivated plants, cultivated plants in general do differ in many respects from typical wild species. These differences are considered and their implications for the systematics of cultivated plants are discussed. It is concluded that while formal botanical categories can successfully accomodate both wild and cultivated plants down to the species level (i.e. the level of the binomial), they are inapplicable to the infraspecific levels of the systematics of cultivated plants. A flexible hierarchal system based on grouping of cultivars is proposed as a practical alternative.
Article
The methods of formal taxonomy have not been very satisfactory for the classification of cultivated plants. As a result, the people who deal with cultivated plants the most have developed their own informal and intuitive classifications based on experience as to what constitutes useful groupings. An attempt is made to provide a framework in which both systems can operate with a minimum of confusion. The structure of the total available gene pool is characterized by assigning taxa to primary, secondary and tertiary gene pools. At the infraspecific level, cultivars are grouped into races and subraces in an informal way without rigid rules for the use of terms.
Article
In an attempt to alleviate extensive confusion regarding infra-specific variation of Humulus lupulus (s.l.), numerical taxonomic analyses were conducted on 783 herbarium collections of this species. A method combining alternating cycles of principal coordinate analysis and canonical analysis was used to generate morphologically defined groups, the taxonomic acceptability of which was judged on the basis of geographical homogeneity. This technique produced five groups, which are formally recognized here as varieties. Humulus lupulus var. neomexicanus occupies western North America, especially the Cordillera, and is largely allopatric. Humulus lupulus var. pubescens (var. nov.) inhabits the American Midwest. Humulus lupulus var. lupulus occurs in Europe, where it is allopatric, and is introduced elsewhere, especially in eastern North America, where it comprises half of the herbarium plants from this region. Humulus lupulus var. lupuloides (var. nov.) occurs in the eastern part of North America, and intergrades with the other three varieties populating North America, wherever it is sympatric with them. Humulus lupulus var. cordifolius is found in eastern Asia, mainly in Japan. Attempts to cluster these variants hierarchically did not reveal an unambiguous pattern of relationship, although several of the techniques used produced the intuitively satisfying separation of the three North American taxa from the Asian variety and the European variety. Humulus japonicus, a distinctive relative, does not manifest comparable geographical differentiation. Humulus yunnanensis, a Chinese endemic species first described in 1936, has been almost universally unappreciated and identified as H. lupulus, which it resembles superficially. However, it is more similar to H. japonicus. Two contrasting genetic systems are perceivable in the four species comprising the Cannabaceae: Cannabis sativa and H. japonicus seem to have "general purpose genotypes" adapted to cosmopolitan distribution, whereas H. yunnanensis and the varieties of H. lupulus appear to be comparatively specialized for localized habitation.
Article
A quantitative analysis procedure for tetrahydrocannabinolic acid, cannabichromenic acid, cannabidiolic acid and cannabigerolic acid monomethyl ether was established by gas chromatography and by a combined gas chromatography-preparative thin-layer chromatography method using cholestane as an internal standard. The variations of cannabinoid contents with leaf-age, season and sex were investigated in three kinds of "physiological varieties" of Cannabis sativa L., the Mixican, the Minamioshihara No. 1 and the CBDA strain.