Capturing the Full Genetic Potential of Cannabis

While a single cannabis seed may not contain the same wide range of genetic possibilities or variation, there is still a wide range of expressions within the Cannabis genus, be it from genetic makeup, mutation or environmental influences such as nutrient composition, lighting spectrum or temperature.

Many cannabis seeds available for commercial production today are fairly stabilized, and many chemotypes produce similar phenotypes. However, within the phenotypes, there are variations, some that are more desirable than others. That’s why growers regularly “phenohunt” to discover or find characteristics they desire.

But there is still so much to learn from the cannabis plant. Despite the fact cannabis is one of the most researched plants compared to any other commercial crop—the University of Mississippi’s National Center for Cannabis Research and Education has been studying cannabis for more than 50 years—due to cannabis prohibition and the stigma associated with it, our knowledge remains limited, and genetics is just one example. There is much to learn and explore regarding cultivating cannabis to its full genetic potential. There are many anomalies or unexplainable responses or outcomes regarding variations within cannabis genetics that can be discovered.

Mutations: Worthy of Further Exploration?

Plant mutations, also known as breaks, sports or chimeras, are naturally occurring genetic mutations that can alter the appearance of the foliage, stems, fruit or flowers of any plant. Cultivars such as Freakshow and Dr Grinspoon are fascinating, well-known examples of cannabis mutations. Most mutations are random and are a result of an alteration or change within the cells of a plant, but both cultivars have been selected so the mutation is consistent. Neither Freakshow nor Dr Grinspoon resemble a common cannabis plant. Dr Grinspoon is described as “leggy” or “stringy” with mostly bracts and very little vegetative material/ leaves, besides stems. Freakshow, available via seed and pictured throughout this column, has leaves that resemble a fern more so than a cannabis leaf, yet it produces flower akin to a traditional cannabis plant.

Mutations can sometimes be triggered by environmental influences such as extreme pH fluctuations, insect damage, cold temperatures or extreme temperature fluctuations, chemicals or viruses. One of the most famous examples of this is The Semper Augustus tulip, the most expensive tulip bulb ever sold. It first sold in the 1630s and fetched a price that could have paid for an expensive house on an Amsterdam canal at the time, in the richest neighborhood. The irony is that the characteristics that made it so unique and desirable was the result of the “tulip breaking virus,” the name describing how the pathogen “breaks” one petal color into two or more colors, creating a beautiful pattern resembling flames or feathers but one that ultimately kills the plant. The tulip-specific mosaic virus creating the vivid streaks also weakens the plant from bulb to offshoots, ultimately stunting the plant and causing it to wilt. The plant is no longer in production, but this anomaly is just one example of the possibilities of genetic expression, even from a pathogen.

A mutation in cannabis can cause leaves and other aspects and appearances of the plant to no longer resemble a cannabis plant. There are many examples of cannabis mutations that are not simply genetic diversity or natural expressions, including:  

• Creeper grows out and low, not tall. Branches can grow toward the ground and root at the point of contact with the earth.
 
• Duckfoot or Ducksfoot, a term meaning Pinnatifid lobed or “webbed foot,” is a leaf mutation that produces webbed leaves.
 
• Variegation/variegated plants or albinism, which are flower or other plant parts without pigmentation that appear white instead of the green typically found in cannabis plants.
  
• Vine Cannabis, as the name implies, resembles a plant more akin to a vine or a hops plant, which is a close relative to the cannabis plant.
 
• Polyploidy, which is common in plants, is a scientific term meaning plants with two sets of chromosomes. In a cannabis polyploidy mutation, the plants have three complete sets of chromosomes, which can result in extra developed areas. It is potentially possible that polyploidy mutations could produce flower with increase potency, but research is needed.
  
• Whorled phyllotaxy produces an extra leaf at the node, which is unusual, but not typically desirable unless it also exhibits another desirable trait.

Research into cannabis mutations is limited, and I’ve always wondered what if one of these unusual plant mutations also produced desirable, uncommon levels of terpenes or cannabinoids, say a high concentration of THCV? And what if the concentration of THVC peaked in week two of the flowering cycle? You’d save six weeks of flowering, reducing the cost of production. What may be seen as a mutant and an undesirable plant could be the catalyst for a breeding program that produces something unusual that everybody wants.

Endless Possibilities

Because environmental factors influence expression, other than breeding work, cultivators experiment with different conditions to see how plants respond. For example, I had a conversation with a California grower recently who places ice packs on top of potted plant soil during the last two weeks of the flower lifecycle, as well as irrigates with water chilled to 40 to 50 degrees F. When making these adjustments, combined with lower environmental temperatures, the grower said the cultivar expressed purple-colored buds, which are popular with her customers. Although further testing is needed to explain the variation, this is one example of where environmental adjustments might help to accentuate a natural genetic expression. 

Other than testing and experimentation, I’ve also wondered if seed size or shape can be a clue to what might sprout. This thought crossed my mind while I was at a seed production/breeding facility. For fun, I was sifting through a handful of a specific cultivar of seeds that were various shapes and sizes. Is it possible to determine which seed is best by merely looking at it? Is it the biggest viable seed? Or the smallest? The answer could vary from one cultivar to another, but it would be interesting to conduct a large experiment to discover if the larger or smaller seeds would outperform the other in some way or would they all be fairly uniform in most respects.

Another question that has crossed my mind is how maternal and paternal influences are expressed in cannabis plants. Which has the dominant influence when breeding cannabis plants? Are the desired characteristics more dominant in a male or female cannabis plant? A 2015 study showed that in mice, the paternal/male influence is slightly more dominant than the maternal side. However, dominant and recessive genes from both parents play a role, and in cannabis, mothers are dominant. I’ve always wanted to perform an experiment utilizing two male plants and two female plants from two different cannabis cultivars. Call them cultivar A and cultivar B. First, I would breed the male cultivar A with a female from cultivar B. Conversely, I would in turn breed the female of cultivar A with the male of cultivar B, thus reversing the dominant genetics of the two cultivars. Typically, when breeding cannabis, the best practice is to utilize the female to source and bring forth any desirable traits or natural expressions/phenotypes, as these are more easily detectable. That said, I am still intrigued by the process of reversing the maternal/paternal order, simply to witness how that affects the outcomes, as well as any minor detectable nuances or expressions. The first foreseeable hurdle to overcome would be in selecting a preferential or superior male to breed with, as it is far easier to select a superior female cannabis plant than it is a male cannabis plant. Besides growth characteristics such as tall or short and early or late flowering, the only relevant data one can glean from a given male specimen besides origin would be from a thorough lab analysis regarding both cannabinoid and terpene profiles. Testing is expensive, and having males in a facility is risky. Anomalies or unusual or usual desirable traits are typically not expressed. That said, not all males are equal, and if growers investigate and have lab results to help guide them, they could isolate what can be deemed a superior or preferential male to breed with. 

Tomorrow in Genetics

These are just a few examples of how wondrous and diverse the cannabis plant is and just one reason it has been bred and revered for thousands of years. With many thousands of cultivars having existed, and the thousands of cultivars available today, one can see the plethora of possible genetic expressions, as well as the environmental influences possible, both desirable and not. In an industry where price compression is a reality in many markets, having proprietary genetics and a stable supply of what sets you apart can help companies survive. Protecting and patenting those unusual genetics is crucial.

With such diverse possibilities within the genetics available today, more research is needed to scientifically determine methods of truly giving each cultivar exactly what it wants, exactly when it wants it, and to maximize every desirable characteristic or quality from a given cultivar, or to maximize production of a desired alternative cannabinoid or terpene. Is it possible to extol the desirable traits of a mutant to increase yields of any plant, as well as potency? Perhaps cannabis does not have 5,000 possibilities in one seed, but those that do exist must be further explored. 

Kenneth Morrow is an author, consultant and owner of Trichome Technologies. Facebook: TrichomeTechnologies Instagram: Trichome Technologiesk.trichometechnologies@gmail.com