While many strategies exist for propagating plants, only tissue culturing allows the grower to propagate genetically identical, disease- and pest-free clones of a pre-screened mother plant. Cannabis-specific tissue culture permits rapid clonal multiplication of plants with desired traits.
How It Works
Tissue culture is based on the principle that plants allow plasticity of development. That is, they are able to adapt their developmental path if they are triggered to do so. For example, while cells from the heart of a human could not generate a lung, cells from a plant stem can easily regenerate roots and leaves, and form a whole new functional plant!
Plant tissue culture requires fastidiously sterile conditions, as these individual starter cells and plant pieces must grow in nutrient-rich culture, making it highly vulnerable to microbial contamination.
A wide variety of media has been developed for plant tissue culture, with media specific for different cannabis cultivation. Media components must contain a carbon source, inorganic salts, macro and micronutrients, vitamins, lipids, amino acids and hormones. As in humans, plant hormones help stimulate growth and cell division, and each hormone has a specific role. While some promote shoots, others prompt root growth.
Advantages of Tissue Culture Over Making Cuttings
While a grower can also clone a mother plant by making cuttings (and taking advantage of the plant plasticity principal), this method carries several disadvantages.
First, the grower will not obtain anywhere near the number of plants obtainable with the tissue culturing technique.
Second, cuttings require more space, light, and water compared to tissue culturing.
And third, a huge drawback is that there is no guarantee that all the cuttings will be disease-free. The elegance of tissue culture is that all clones will be maintained in a bacterial and fungal disease-free state. Because tissue culturing is performed under sterile conditions and grown in sterile media, these microbes are prohibited.
Pests that might otherwise be attracted to a soil-based propagation are also forbidden. Viruses can be particularly insidious microbes, as they cannot be seen on your plant; only the symptoms of their infestation are visible once they manifest. However, there is no way to “cure” a plant of a virus.
Tobacco Mosaic Virus, in particular, is the bane of many cannabis growers. Fortunately, tissue culture propagation allows the grower to excise the very tip, or meristem, of the growing shoot of a mother plant for propagation.
The advantage of using this single-cell-layer for propagation is that it outgrows any virus lurking within the plant. Once a newly cultured, clean and healthy plant is established in tissue culture, it now can be used as disease-free stock for your new round of massive propagation.
And so on and so forth – the growing cycle continues. Pretty cool, right?! We think so too.