Why breeding cannabis is unlike other crop breeding efforts
Date:05-02-2019
By Inbar Stern, Vice President of Sales and Business Development, Phenome Networks Ltd.
Part I
The cannabis market today presents a huge demand for new and exciting products containing cannabis ingredients. Producers expect reliable and stable plant varieties to assure their products provide consistent quality. For that, we need to look at the very beginning of the cannabis products supply chain, the breeding research phase which develops cannabis varieties.
A breeding program starts with defining a product profile which includes several desired traits that the end product should include in order to be sold commercially and bring value to the market and income to the company. This breeding profile translates into breeding goals. Until five years ago, there were no organized, long-term cannabis breeding programs resulting from professional planning. The cannabis crop was handled by underground figures operating illegally and not by professional plant breeders or agronomists who understand plant genetics. This resulted in today’s urgent need for cannabis breeders involved with classical (Mendelian) breeding to define initial, basic goals for cannabis breeding programs. Very little knowledge exists today about the cannabis plant, its habits, fertilization needs, irrigation needs, environmental preferences or growing optimization.
Once breeding goals are defined, the second phase is to advance generations and create pedigrees with genetic variation. Breeding goals defines what the product should include. Genetic variation is how we are going to achieve these goals. The breeder needs to prepare plant populations that have the right genes to enable development of desired varieties. For years there was very little effort given to creating genetic variation. Most cannabis varieties being used today lack genetic variation and are actually very similar genetically to one another.
Buyers are asking for more. The potential for the plant across multiple industries is almost unquestionable. Breeding efforts done by professionals will support the improvement of germplasms used in breeding programs and will reduce costs of development and production. Only professional breeding can provide new genetics that are more consistent with quality ingredients such as yield, cannabinoid production, resistance to diseases such as powdery mildew disease, indifference to day length and control over the plant’s sex.
Part II
The cannabis industry today is encountering problems that breeding efforts can prevent. For example, cannabis is highly impacted by the length of the day and needs different growing environments for different phases of its life cycle. It requires a long-day environment for plant development and a short-day environment for flowering and cannabinoid development. In practice, plants are constantly moved from one environment to another by growers. The large investment required to maintain plants and the right environmental conditions reduces the profits for a cannabis breeding company.
Controlling the sex of the plant is another daily struggle for cannabis growers. Both male and female organisms can be expressed on the same plant (dioecious plant) but only female plants produce cannabinoids, the active ingredients with medicinal and recreational value and terpenoids with aromatic oils that give cannabis its distinctive smell. A female plant can suddenly change its sex, develop pollen, fertilize flowers in the growing area and render the plants unusable. Because it is not yet known how to control the sex of the plant, growers manually separate male plants from females and remove them from the growing area.
Multiplication of cannabis plants has been traditionally done via vegetative propagation, not with seeds. A grower would observe early generations of plant populations expressing higher levels of genetic variation and select an excelled plant. This process has proved to be problematic because cuttings do not propagate true to form. After a few generations, the chemical profile of the cut plants could be totally different than the mother plant. Production from these products could not be approved for medicinal use.
As it stands today, each cannabis seed is different because the parent lines are heterozygotes and unstable. To overcome these challenges, cannabis breeders using breeding tools such as DNA markers are working to gain genetic control over cannabinoids plant profile and heterosis’ effect. This would allow transition from cuttings to hybrids seeds.
Although breeding efforts takes time and resources, in the long run it is worth the investment. If breeding is done widely and in parallel by many companies around the world, better cannabis products could be developed in shorter time with less effort and fewer resources. Breeders could thus recover their investment.