1. Blog: Micropropagation process

Micropropagation process

The complex process of micropropagation can be summarized in four resp. five main stages:

Stage 0: Stock / elite plant selection

The first step is a selection of plants with suitable characteristics for mass propagation. The selected plants, then must be kept for about three months in a controlled environment with low humidity, irrigation and without the risk of microbial infection. [1]

Stage 1: Aseptic Culture Establishment

In stage 1 the chosen explants have to be prepared with suitable sterilizing agents and then placed on well-defined culture medium. After that the cultures have to be incubated at a 16-h photoperiod at 3000–10,000 flux light intensity. [1]

Stage 2: Multiplication of the Explants

After inoculation and incubation, the explants produce multiple shoots. The quantity of shoots depending on the progeny process and the type of explant. [1]

Stage 3: Germination of Somatic Embryo or Rooting of Regenerated Shoots

To induce rooting, the produced shoots of stage 2 have to be placed on rooting medium or sometimes directly in soil depending on moisture conditions. [1]

Stage 4: Hardening

In the last stage, the rooted plants need an acclimatization period to prepare them for external soil conditions after the in vitro environment. During this period the plantlets need to become resistant to stress, diseases and moisture. Therefor they require protection of direct sunlight and moisture should be kept at a lower level over a period of time. This guarantees, that the plantlets grow well-developed roots and form cuticular wax. [3]

Error sources

The micropropagation process is in practice a complex method with some possible error sources. It is important to choose the right chemical compositions of sterilizing agents and culture/ rooting media.
Moreover the change from in vitro to external conditions is delicate and needs a lot of attention.
Vitrification can be a problem as well because of inappropriate in vitro condition. [4]
Furthermore sterile work conditions are necessary to prevent any contamination. Also work tools need to be sterilized either with ethanol or with heat (Bunsen burner) [2]  

Micropropagation application

With Micropropagation it is possible to produce large amounts of plants in a short period of time. Therefore it can be an appropriate tool to produce plants for plant-based medicine. For example an effective and fast production of Catharanthus roseus with a large amount of different alkaloids. [5]

References:

[1] Bhatia S., Sharma K., Dahiya R., & Bera T. (2015). Chapter 11: Micropropagation. Modern Applications of Plant Biotechnology in Pharmaceutical Sciences. pp. 361-368
 

[2] Plant Tissue Culture: Micropropagation, https://www.youtube.com/watch?v=hgOqTyiI_30
 

[3] Gaspar T., (1991), Vitrification in micropropagation. Biotechnol Agr Forest; 17:116–26.
 

[4] Ziv M., (1991) Quality of micropropagated plants – vitrification. In Vitro Cell Dev Biol 1991; 27(2):64–9.
 

[5] Debnath M., Malik C.P., & Bisen P.S., (2006), Micropropagation: A Tool for the Production of High Quality Plant-based Medicines, Current Pharmaceutical Biotechnology, pp. 35-49