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]
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
