As a cannabis enthusiast, have you ever wondered how the cannabis plant is bred? There are several biological processes that are involved with the sexual propagation of cannabis and how new generations of seeds are made through cannabis breeding. A cannabis plant can either be reproduced sexually or asexually. For asexual propagation, the cannabis plant uses cloning and cutting to propagate and create new plants. On the other hand, sexual breeding occurs when gametes, or male and female plant parts, unite in the female flowers in order to create a unique and genetically distinct breed. To learn more about this type of breeding for cannabis, keep on reading.
The Bioprocesses of Cannabis Breeding
Every seed that was created using sexual propagation possesses the genes of its parents. This means that the seeds are genetically unique, and they contain a combination of essential characteristics from each of their plant parents. Breeders are also able to utilize these skills of sexual reproduction and take it as their advantage by cross-breeding the characteristics and traits of one plant to other strains.
One of the most important benefits of crossbreeding cannabis plants is forming strains that are able to withstand diseases and pests through cannabis breeding. As cannabis is a dioecy or dioecious plant group, marijuana plants have male and female counterparts.
Male plants are distinguishable from their stamens or the pollen sacs that they create and grow from their own branches. The females, on the other hand, are known for the two white or pink hair-like structures which develop as a part of their pistils. Some plants exhibit both the sexual characteristics of males and females. They are known as monoecious plants, hermaphrodites, or intersex cannabis plants.
If you are targeting a growth of a seedless cannabis plant, you might want to throw away any male or hermaphrodite plant because they might be able to pollinate your cannabis plants. If you are breeding for cannabis seeds, you will want to take care of the male plants because they are essential for the process of pollination. But, hermaphrodites are still undesirable since the seeds that they produce also tend to have hermaphrodite characteristics.
Cannabis plants for breeding are a species of the plant that is anemophilous, which means that it can be pollinated through the movement of pollen in the wind. The male plants undergo a process called dehiscence, which is the process of shedding pollen and dispersing it into the wind. As the pollen is swept away by the wind, it is hopefully carried into a female cannabis plant’s pistils and seeks to pollinate the flower.
Though there are other plant species that send their pollen into the air, the cannabis plant is equipped with the knowledge to recognize if the pollen is taken from the species of a cannabis plant. In fact, cannabis plants have evolved their recognition systems to make sure that only species specified pollen will be able to pollinate the female plant.
How to Breed Cannabis Plants
After two-parent cannabis strains are selected for breeding, a male and several female strains are placed in a contained breeding chamber so that the pollen will not be able to escape. A breeding chamber can be an enclosed environment with plastic sheeting or a specially designed sterile environment for large-scale breeding.
A single healthy male cannabis plant can be equipped to pollinate up to 20 female plants. According to Nat Pennington of the Humboldt Seed Company, a single male plant can absolutely cover tens of females with its seeds, if we are talking about the pollination effort. And that is just for intentional breeding. If you place a male in the wild or wide-open space, a single male can easily pollinate even hundreds of female cannabis plants.
Once they are placed inside the breeding chamber, the plants can grow vegetatively for a few weeks so that they can grow bigger. Place them on a flowering light cycle of 12 hours of darkness and 12 hours of light.
Mature males can start growing their pollen sacs within the first couple of weeks of flowering. The pollen will be unconfined from the sacs, move through the air, and land on the female cannabis plants. This will induce the pollination to begin. Having a breeding chamber that is enclosed would prevent outside pollen from getting in and inside pollen from getting out.
Growers can also help pollen to be absorbed by the female plants by shaking the pollen from the male plant into the female cannabis plants. You can also collect the cannabis pollen from the males and directly apply them to the pistils for pollination to immediately occur. Then, the female plants will continue to flower and grow, during which they will develop buds and seeds. These seeds will have the characteristics of both the male and female plants that served as their parents.
Once these seeds mature, they are harvested, dried, and stratified before it should start germination. Generally, the entire process will most likely take about three to four weeks before the harvest period begins. These seeds, which are genetically considered as a hybrid, will be able to grow on their own should you decide to plant them.
Some Terms To Know When Breeding Cannabis
- Genotype – This refers to the entire genetic makeup that an individual has. It has the power to describe the entire set of a single organism.
- Phenotype – This refers to all the characteristics of an individual from the genetic characteristics taken from the genotype. These involve traits that are visible to the eyes. It can involve leaf shape, bud color, and size.
- Alleles – This refers to the alternative versions of a given gene.
- Heterozygous – This means having two different alleles of a particular gene. For instance, a plant can have 1 allele that says the leaves must be green, while another allele says that the leaves must be blue. The result will be either of the two or something in between.
- Homozygous – This means having two identical alleles of a particular gene or genes. For instance, if a plant has a homozygous allele for having broad leaves, it will produce broad leaves.
Why Should A Strain Be Stabilized?
Genetic stability is something that should be targeted to be achieved, especially if the strain you have made has redeeming qualities that can change the entire cannabis industry. However, if you find trouble in trying to stabilize the strain, it would be harder to produce a similar strain. Here is how you can stabilize a cannabis strain:
- Selfing – This technique involves pollinating a female plant with itself. To do so, the grower must learn to make a female produce male flowers by spraying them with colloidal silver. Then, their pollen must be collected and then use the pollen for the other branches of the same plant. When you commit to selfing, the only seeds that you will be able to produce are female ones. Additionally, if you start selfing, the characteristics are increased by 50 percent. This is a great way to stabilize a cannabis strain if that is your ultimate goal.
- Backcrossing – This technique consists of crossbreeding a plant with its recurrent mother plant. This means that a chosen plant from the offspring must be crossed back with one of the parents each time. When this practice is done, breeders will be able to establish a strain with a similar genetic identity to the chosen parent. A great advantage of this technique is that you can work with both male or female plants at the same time. But the disadvantage with backcrossing is that breeders will only be able to fix a trait if it is homozygous in terms of gene coding.
- Line Breeding – Inbred lines are cannabis strains that breed true for a specific number of characteristics. A true-breeding strain will involve using a single primary phenotype with very little variations. To do this, the cannabis growers must have a specific characteristic list in mind of the traits they want their strain to have. Once they are able to find 1 male and 1 female, or 2 females, to match their specific criteria, so that seeds can be made from them. Then, the same process must be done for the next set of offspring. Generally, you can play around with 5 traits. But, you cannot focus on too many at a time because it would be a little harder to achieve that many similarities.
Can Cannabis Home Growers Succeed In Cannabis Breeding On Their Own?
While we cannot deny that better results can be achieved by professional cannabis breeders, good and stable strains can also be produced by amateur home growers. After all, cannabis breeding does not only need skills and knowledge, but it is also a numbers game. And just because of that reason, home breeders, as long as they focus on only one line per time, will be able to maximize the number of plants they will be able to produce. Plus, optimizing their growing space can go a long way even for beginners. With experience, discipline, patience, and a great deal of courage, home breeders can successfully breed their own new strains of cannabis.