Even the most brilliant minds in their respective industries can get things wrong. It can happen due to experiencing something contradictory to the common rhetoric, breaking new ground in the field, or simply interpreting results in a different way. There are many other ways in which experts can generate different viewpoints from each other and the mainstream understanding.
It is relatively commonplace in any hypothesis-driven field for the top minds to have conflicting opinions. In the cannabis industry, this is also true, and, like many other examples, there is often room for seemingly opposing viewpoints actually to work in harmony.
Cannabis cultivation is full of ‘horses for courses’ examples, where two seemingly differing approaches can deliver high-end outputs. This ‘paradox’ is compounded in cannabis partly by the use of language, which is often unique, hard to define and generally unclear. However, what is clear is that the global cannabis industry is undergoing massive professionalisation, and this comes with both an increase in relevant information and a weeding out of the misinformation. The use of common words, universal definitions and interdisciplinary knowledge all have a seat at the table of language use, making it an essential thing to get right.
As the highly skilled growers from North America have now had several years of working in ‘the light’, there has been a massive uptake in the knowledge these individuals have both shared and absorbed. There are a lot of excellent growers out there, and there is a subgroup of those who cannot explain why they are so successful and a smaller handful that can explain it at all levels, including the molecular biology and the facility management levels. A round of applause is the least these guys and girls deserve - learning science from the outside in, is such a complex undertaking that it is no wonder some things get a bit muddled in translation. Although there are quite a few terms that invoke confusion and misunderstanding, for this article, the focus will help to clarify some common cannabis terms.
Genetic Drift - A Term Often Used Erroneously
This phrase is often wrongly used to describe changes in a plant’s performance and loss of vigour due to sequential asexual propagation, i.e. clone-to-mother-to-clone-to-mother. This loss of vigour, yield, potency etc, is not due to genetic drift. In fact, that phrase makes no sense at all to this argument. Genetic drift is a population genetics term used to describe how the genetics of a population have changed over time.
A good example of this is lactose tolerance in humans. By default, most mammals will express a gene that helps them break down lactose, allowing them to drink, for example, cow’s milk. It is also true that most mammals turn this gene off during/at the end of weaning. In the human population circa 30k years ago, this was the default genetic profile, where the gene responsible for breaking down lactose is turned off between the ages of 2 and 4. The story goes that after a mutation and some selection pressure (theorised to be drought), an individual appeared with a mutation that meant this gene was not turned off at toddler age as normal. This meant that during drought, this adult (and then their offspring) could drink cow’s milk, for instance, where others could not. Fast forward to the present day, and we find that lactose tolerance is the new default state, with fewer people now being intolerant than at the time of that first mutation.
This is genetic drift, where slowly, over time, the genetics (in this case, a single gene), change and result in a different phenotype, and this phenotype becomes the most prevalent phenotype in the population. Usually, it is also true that the original genetic profile remains in the population but at a much lower frequency; hence, the genetics drift from low to high frequency in the population. Cannabis growers will sometimes say genetic drift when they mean the phenotype has changed, usually resulting in a loss of vigour, lower cannabinoid levels or even a different chemical profile. This is likely due to a build-up of many stresses over time, and an increase in the prevalence of pathogenic organisms -although other factors could be influencing the performance as well.
Mendelian Genetics, F1, and the Terms of Dominant & Recessive Gene Expression
If both parental lines have been driven to homozygosity (are stable for the desired traits), then crossing them will create an F1. It usually results in a high-vigour cultivar with a predictable and uniform phenotype; therefore, that genetic line is a true F1. In this scenario, if each gene (two possible copies from each parent) is the same, then dominant and recessive alleles will segregate perfectly, resulting in every individual having a similar phenotype in the same environment. However, it is far more common for breeders to use breeding stocks that are themselves F1s or at least relatively recently developed lines, i.e., not homozygotic (the desired trait is unstable).
This is why understanding the generation and the stability of the parents is essential. As every cannabis aficionado is well aware of what an F1 is, this is not an attempt to redefine it or accuse them of misunderstanding the concept. I have had to argue for the upstream and practical side of this on numerous occasions when breeders tell me they have a good F1 that is stable and uniform, with 7 phenotypes! This immediately sets alarm bells ringing - this implies that the F1 has a typical F1 phenotype spread based on homozygous parents, meaning that all progenies show true segregation. However, in most cases, all the desirable traits are not perfectly segregated, and if the breeder says it’s F1 with 3 phenotypes, then it clearly did not come from homozygotic parents.
This problem is further compounded by multivariant factors and polygenic traits, where several genes influence one trait. The inheritance here is harder to predict and often breaks the typical dominant recessive pattern. The standard Mendelian genetic formula predicts ratios of progeny based on heterozygous or homozygous parents for a specific trait; it cannot account for multigenic traits, epistatic relationships, or even co-dominance.
As cannabis and humans are similar genetically speaking, it’s worth mentioning that in XY sex determination and diploid genome, each gene can have different alleles (versions of that gene). For example, in the gene for eye colour, one person may carry one allele for blue eyes and one for brown eyes (each one inherited from a different parent). Therefore, describing genes as dominant and recessive only tells the observer which are dominant and recessive between the two alleles of that one gene. It is more like the card game, ‘higher or lower’, where the outcome depends on the current number and whether the next is higher or lower. Therefore, if the gene for blue eyes is recessive to that of brown eyes, it doesn’t necessarily mean that blue eyes are always recessive or brown eyes are always dominant. It only tells us the relationship between the two. If we brought in another allele of the same gene with a different phenotype, green eyes, for example, then there is a possibility that in one pairing, one allele is recessive, and in another pairing, the same allele is co-dominant.
Cannabis Reproduction - Common Misnomers
Cannabis is largely what is known as dioecious, which means a plant will tend to show male or female sex organs but not both, driven by the XY chromosomes in males and XX in females. In dioecious populations, individual plants are strictly either male or female. This sexual dimorphism is genetically determined, with male and female sex chromosomes (analogous to the XY system in humans). The male plants produce pollen, and the females produce ovules. This separation of sexes promotes outcrossing, which can increase genetic diversity within a population, a substantial evolutionary advantage. However, environmental stress or genetic mutations can occasionally lead to the manifestation of both sexual organs in dioecious plants, commonly called hermaphroditism. This, again, carries a significant evolutionary advantage over plants that cannot.
For example, if a seed is dropped in an isolated and harsh environment, a strictly female plant can be ‘stressed’ into producing pollen, allowing it to create seeds and then the plants to establish a population in the new environment. In contrast, monoecious cannabis plants have both male and female reproductive organs on the same individual. This is less common in natural Cannabis sativa populations but is sometimes seen in cultivated varieties (cultivars), especially sinsemilla (seedless). Monoecy can be advantageous for certain agricultural practices, too, as it ensures the presence of both male and female flowers in a given population, facilitating pollination and seed production.
However, the terms "hermaphrodite" and "intersex" are often used to describe what a botanist would call "bisexual". There are levels of detail to the use of each word with distinct botanical implications. "Hermaphrodite" is frequently used to describe cannabis plants displaying both male and female reproductive structures. This dual sex expression can arise in dioecious cannabis varieties as a result of environmental stress or genetic factors, causing traditionally female plants to develop male flowers (pollen sacs), or the reverse. This hermaphroditic characteristic is often seen as undesirable in cannabis cultivation, especially when the aim is to produce seedless cannabis. "Bisexual" is a more fitting term in a botany context and closely aligns with the concept of hermaphroditism. It refers specifically to the presence of both male and female reproductive organs in the same plant or, more specifically, within the same flower. In cannabis, this term can be used interchangeably with hermaphrodite when describing plants with staminate (male) and pistillate (female) flowers. Meanwhile, "intersex" is a term borrowed from zoology, where it describes organisms that do not conform to standard male or female physical sex characteristics.
Its application in the context of cannabis is less conventional and can be potentially misleading. However, it might be used to denote cannabis plants showing a combination of features predominantly associated with both sexes, diverging from the typical expressions of male and female plants. This term is less precise and less commonly used among botanists than "hermaphrodite" or "bisexual" in plant biology. In fact, a botanist may even ask, ‘To what extent is the opposite sex showing?’ i.e. all or only a few of the flowers display both sexes. This is because if only a few female plant flowers show male reproductive organs, the botanist would probably describe it as polygamodioecious, a bit of a mouthful. This literally means a single-sex plant displaying flowers of the opposite sex sporadically throughout the plant. Polygamous is a general term for multiple reproductive types in the same plant, i.e. male, female and bisexual flowers.
Conclusion
Semantics and special language use are hardly the thorn in the side of the industry. It is less important than many other aspects of producing a satisfying crop. However, as the industry reaches higher levels of professionalism, it could become an issue if the language used to describe problems, solutions, or even new techniques isn’t professionalised with it. Examples of the misuse of language are plentiful and can cause issues in simple terms, such as the inaccurate description of physiology leading to misdiagnosis of disease. It is quicker and easier to work on a problem if everyone involved uses the same terms and knows what those terms mean. Cannabis cultivation guides and books are great - especially for describing physiology generally - but the broader biological terms are often used when they are only partly understood, hence the need for clarity.
