Tissue Culture and Micropropagation: The Future of Plant Propagation?

In today’s article you can broaden your growing horizons and discover a new global trend in plant propagation through cloning via tissue cultures. This method is still a lesser-known way of propagating plants compared with the well-known cultivation (propagation) from seeds or cuttings, which for many years were the only ways to multiply plants.

What is micropropagation with tissue cultures?

To answer this question, we first need to set some boundaries between the terms micropropagation and tissue culture. What is the difference between them and how are they related?

The micropropagation process requires tissue culture to multiply plantlets. These two terms are often used interchangeably. The main difference is that micropropagation refers in practice to the controlled production of a large number of plants from a small amount of plant material, while tissue culture can be considered the initial step of micropropagation for the purpose of plant multiplication. Hence, micropropagation of tissue cultures.

Micropropagation:

• Multiplication of plants by growing plantlets in tissue culture and then transplanting them
• Two steps are tissue cultivation and introduction of new plants into soil.
• Used to produce large numbers of clones.

Tissue cultures:

• A technique for maintaining and growing plant cells, tissues or organs, typically on an artificial medium in suitable containers in a controlled environment.
• Three steps are placing an explant into tissue culture medium, multiplication and initiation of root formation.

This cloning technique uses plant cell cultures. They are grown on sterile Petri dishes. As with classic cuttings, the process begins with a mother plant. However, only an explant — a plant sample — is taken, which is then placed into a sterile environment, usually a nutrient gel medium containing essential nutrients including vitamins and hormones that stimulate shoot and root development of the young plant.

The controlled cloning environment allows tissue cultures to be stored practically indefinitely until the grower decides to use the sample. Whether the sample needs growth, root formation, or multiplication at that moment, these processes can be initiated at any time by adding additional nutrient- and hormone-rich solutions. Once the plant is sufficiently developed and ready for propagation, an unusually high number of identical clones are produced.

A careful reader will already see that the almost laboratory-level work with tissue cultures goes beyond typical indoor gardening toward microbiology, and therefore requires an exceptionally clean environment. But if you like experiments, go for it. A home micropropagation kit is enough. A sterile starting environment is crucial for future plants so pests or plant diseases do not occur.

When genetics takes the lead

An indisputable advantage of tissue cultures is that clones remain genetically identical to the mother plant.

This is also where cloning via tissue cultures outperforms traditional methods, as it is more precise, cleaner, and thus allows growers to secure exactly the genetics they need. Traditionally propagated clones are also generally more susceptible to diseases and may suffer genetic mutations from the original mother plant.

That is why tissue cultures are increasingly used to achieve specific high-value genetics.

Genetic stability is often a priority in the growing world, and micropropagation with tissue cultures meets this need perfectly.

On the other hand, compared to clones, growing new plants from seeds cannot be recommended much in terms of genetic stability. The whole process is also longer and more costly, especially if you are growing herbs with medicinal effects, which usually root relatively easily and quickly.

Solution for commercial and smaller growers

Undoubtedly this is not only the future but in many cases already the present for commercial growers. Tissue cultures are already routinely used by, for example, large-scale banana growers. This method of cloning, where new individuals are produced from stored cell cultures in the order of thousands within a short time frame, shows extraordinary efficiency at large scale. Producing regular clones in the way we have known requires constant care of the “mothers.” If we focus on popular and frequently discussed autoflowering varieties, long-term maintenance of mother plants becomes almost a “mission impossible,” because so-called autoflowers do not respond to photoperiod changes like classic varieties.

With tissue cultures you have far fewer worries, they take up much less space, and — as mentioned — can be stored for almost unlimited time.

The advantages of tissue cultures naturally also apply to everyone engaged in gardening at a regular scale. Thanks to this revolutionary method, every grower has the opportunity to influence the genetic disposition of their crops.

What are the other undeniable benefits of using tissue cultures?

• Plant genetic material used in tissue cultures is sterilized multiple times — during sampling and later during propagation. As a result, it is virtually impossible to find pathogen traces on the resulting clones, and adult plants later exhibit exceptional vigor and yield.
• Sometimes it is desirable to revive very rare seeds that are several years old. Micropropagation in test tubes can make this possible.
• Have you ever fallen in love with one of your mother plants and been heartbroken to see the quality of the cuttings taken from it decline over time so that they resembled the donor plant less and less? If so, you may know that besides senescence the most likely cause was the gradual accumulation of bacterial, fungal, or viral diseases along the clone line. And as you already know, in tissue cultures originating from a 100% sterile environment you would search in vain for pathogen traces.

Although many commercial growers already successfully use tissue cultures, for the average hobby grower this method of plant multiplication still remains largely unexplored. If you enjoy challenges and innovative techniques, we definitely recommend learning more about micropropagation. If you want to ask us anything, we look forward to your questions at the usual email address info@higarden.cz.

We also recommend these products:

• Plagron Seedbox
• BioNova Starter pack AutoFlower Supermix
• CuttingBoard 27

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