Micropropagation, or the broadly understood obtaining of plant cuttings through in vitro cultures, is currently a commonly used method of clonal plant propagation. Proper use of this technique allows obtaining plants that are genetically faithful copies of the parent plant. What plants do we want to ‘copy’? It is best to only use the most interesting individuals from the population. The idea is to duplicate their unique features and offer the customers the best quality plants. These must be healthy plants, characterized by appropriate growth, interesting colors, leaf shape and resistance to diseases. This method can be used to obtain a huge number of clones of a selected elite plant in a relatively short time.
To establish a tissue culture, the selected elite plant must be deprived of pathogens and microorganisms. To do this, a certain fragment of the plant (explant) must be cut out and placed in a disinfecting solution. Plants require different treatment due to their different structure, thickness of the skin or the presence of a cuticle. Therefore, the disinfecting substance and disinfection time are selected individually for the species. Disinfection can be carried out in solutions of sodium hypochlorite, ethanol, or hydrogen peroxide. After disinfection, the disinfecting substance must be rinsed off in sterile water. Usually, three rinses are used, and then the explant is placed on a nutrient medium.
Medium contains macro- and micronutrients, carbon source, agar and in most cases, growth regulators, or plant hormones, are also added to the media. Most often, these are auxins (indole-3-acetic acid – IAA; indole-3-butyric acid – IBA; 2,4-dichlorophenoxyacetic acid – 2,4-D), cytokinins (kinetin – Kin; 6-benzylaminopurine – BAP) and gibberellins (gibberellic acid – GA3). Each group of hormones is responsible for different processes. Knowing the most common effects caused by the use of a given group of hormones, you can design the composition of the media in order to obtain a specific plant response. Some hormones are responsible for the production of new shoots and their elongation, others for rooting. The proportions of hormones should be selected to ensure the fastest and most efficient growth of shoots.