7 organic supplements used in plant tissue culture media

organic supplements used in plant tissue culture media

Did you know that you can use naturally occurring organic supplements in culture media?

Plant parts under a tissue culture environment require different nutrients to grow into a complete plantlet. These nutrients play an important role in deciding the success of the tissue culture process for any plant species.

But before we dive deeper into the topic of organic supplements, it would also be a good idea to read on different components present in a regular culture media recipe. You can read about this topic in our blog on "8 components of tissue culture media". It is an informative read!

Why do we need extra organic supplements? For certain plant species, the regular media components are not enough. For some other plant species, it is beneficial to provide complex natural compounds to assist in growth and development. However, plant tissue culture requires extensive trial and error in experimentation. The success of an experiment does not only depend on using the right plant material and sterile conditions, but also on the composition of culture media. For every specific plant species and its varieties, we need to curate a different culture media recipe.

What are organic supplements?

In a regular culture media recipe, we add vitamins and amino acids as organic supplements. Plants require vitamins as they act as coenzymes. Coenzymes are molecules that help enzymes to perform their function.

We use amino acids in media as they combine and form different proteins. These proteins help plant cells to build more cells and further develop the plant system. Plant tissues in different growth stages require different doses of organic compounds for satisfactory growth.

In order to enhance plant growth, we can provide naturally occurring organic supplements such as coconut water, potato extract, etc. These supplements are also known as complex organics as their chemical nature is not defined. This means that they have certain components whose effect on plant growth and development is unknown. There are also uncharacterized growth substances present in these supplements on whom research is currently going on. Due to this unknown complex nature, their use may lead to poor growth of plantlets or production of unwanted compounds in the media.

However, the defined tissue culture media does not provide the results we aspire for in certain cases. Hence, it is beneficial to experiment with different complex/naturally occurring organic supplements in such scenarios to obtain better results. You can develop a protocol that is beneficial for the growth of plant tissues under in vitro conditions when doing decent experimentation with different quantities of complex organics in culture media.

Let us now talk about different naturally occurring organic supplements:

Coconut water

This is a colorless mixture of several amino acids, organic acids, plant growth regulators, vitamins, sugar, minerals, and unidentified growth substances. All these compounds help together in the growth and development of tissues in plant tissue culture conditions. You can obtain coconut water from fresh green coconuts.

In several studies, coconut water has been proved to be useful in enhancing the growth of tissues, especially in callus and suspension cultures. This water has mostly been added to culture media recipes for orchid species.

Along with coconut water, coconut milk from matured coconut is also beneficial for plant tissue development. Both of these organic supplements contain large amounts of cytokinins.

Malt extract

This extract is commonly used in the brewing industry. You can produce this extract by germinating barley seeds and immersing them in water for sprouting. Malt extract is a source of carbohydrates and some other unknown compounds. It has been used for developing different citrus plant species under tissue culture conditions. It can also help induce embryogenesis during somatic embryogenesis of citrus plants.

Some studies indicate that malt extract also contains little auxins and gibberellins and encourages plant growth similar to these hormones.

Yeast extract

This extract is a source of different amino acids such as glycine, lysine, arginine, and different vitamins such as thiamine, nicotinic acid, etc. It also has the ability to initiate defense mechanisms in plants. Thus, along with the growth-promoting function, it is also used for developing resistance in plants for different diseases.

DID YOU KNOW?

Yeast extract was the first naturally ocurring organic supplement that was successfully used in plant tissue culture media!

Potato extract

This extract from potatoes contains carbohydrates, different vitamins, and mineral elements. It has been successfully used for anther culture of wheat. Some scientists have also used this extract for orchid culture. You can use this extract along with conventional tissue culture components to develop anther culture protocol for different cereal crops.

Banana homogenate

This natural organic supplement is used largely for orchid propagation. It contains compounds that collectively perform the function similar to cytokinins. It is also known for stabilizing pH in culture mediums and enhancing growth. There are several studies available that have tested the benefits of banana extract for plant tissue growth in different stages.

Algal extract

Microalgae and macroalgae are easily available to anyone. They are known to be a source of phytohormones for tissue culture media. But the phytohormone quantity might differ from one algae species to another. When they are used along with external auxins and cytokinins in a tissue culture media, they result in improved callus growth for most plant species. Because of this reason, they are largely used for callus cultures of pea, tobacco, and beet.

Embryo nourishing fluids

These are fluids from embryo sacs of different immature fruits. Such extracts have growth-promoting and nourishing effects on the development of embryos and tissues. These are largely used by scientists in somatic embryogenesis.

We hope that many of you enthusiasts found this article interesting. For more informational posts on different aspects of plant tissue culture, keep checking this space!

Also if you like this article, do share it with others as well. Let us build a wonderful community of plant tissue culture enthusiasts.

By Nancy Bhatia | 17-August-2021

References

  1. Bhojwani, S.S., & Dantu, P.K. (2013). Plant Tissue Culture: An Introductory Text. Springer India
  2. Robert H. Smith (2013). Plant Tissue Culture- Techniques and Experiments. Elsevier Inc.
  3. https://www.intechopen.com/books/recent-advances-in-plant-in-vitro-culture/plant-tissue-culture-media
  4. https://www.researchgate.net/publication/40103634_The_components_of_plant_tissue_culture_media_II_Organic_additions_osmotic_and_pH_effects_and_support_systems
  5. https://www.jstor.org/stable/2437313
  6. https://www.journals.uchicago.edu/doi/abs/10.1086/334695
  7. https://www.indianjournals.com/ijor.aspx?target=ijor:ijh&volume=64&issue=4&article=018
  8. https://www.researchgate.net/publication/230057060_Identification_of_Zeatin_and_Zeatinriboside_in_Coconut_Milk
  9. https://onlinelibrary.wiley.com/doi/abs/10.1046/j.1529-8817.2004.03046.x
  10. https://www.jstor.org/stable/4353691