TC fundamentals
Tissue culture comes with its own terminology, and understanding the basics makes the whole process much easier to follow. Here we break down the most important terms, materials and conditions you will encounter when working with plant tissue culture.
1.Culture vessel
A culture vessel is the container where the plant tissue and culture medium are kept during in-vitro growth. It provides a controlled environment while allowing enough light and space for the developing plant.
Common examples include glass jars, plastic containers and specialized tissue culture vessels.
2.Culture medium
A culture medium is the nutrient-rich environment where the plant tissue grows in vitro. It provides water, minerals, sugars and other components needed for the plant to develop.
Its composition can be adjusted depending on the plant species and the stage of growth.
3.Agar and gelling agents
Gelling agents are used to turn liquid culture medium into a gel that can support the plant tissue. Agar is one of the most commonly used gelling agents in plant tissue culture.
The amount and type of gelling agent can affect the firmness and water availability of the medium.
4.Plant hormones/PGR
Plant growth regulators (PGRs) are compounds used to influence how plant tissues develop in vitro. Different PGRs and concentrations can encourage processes such as shoot formation, multiplication or rooting.
The right combination depends heavily on the species and the stage of growth.
5.Nutrients
Plants need essential mineral nutrients to grow in vitro, which are supplied through the culture medium.
Murashige & Skoog (MS) medium is one of the most widely used nutrient formulations in plant tissue culture and can be adapted depending on the species and growth stage.
6.Sugar & carbon source
Sugar is added to the culture medium as an energy source for the plant. In tissue culture, plants often cannot produce enough energy through photosynthesis, so the medium usually contains an external carbon source.
Sucrose (table sugar) is the most commonly used.
7.pH
Most tissue culture media are adjusted to around pH 5.6–5.8 before sterilization, with 5.8 being a common target. The optimal pH can vary depending on the plant species and culture medium.
8.Explant
An explant is a small piece of plant tissue taken from a healthy plant and used to start a tissue culture. Depending on the species and the goal, it can be a shoot tip, node, leaf, or another suitable tissue.
The explant is then placed onto a suitable culture medium under sterile conditions.
9.Sterility
Sterility is the condition of having no unwanted living microorganisms in the culture. In tissue culture, maintaining sterility protects the plant from bacteria and fungi that can compete with it or destroy the culture.
10.Sterilization
Sterilization is the process used to achieve sterility. Tools, culture vessels, media and other materials can be sterilized using methods such as autoclaving, heat or chemical treatment, depending on the material.
11.Contamination
Contamination happens when unwanted microorganisms, such as bacteria or fungi, enter a tissue culture. They can grow quickly in the nutrient-rich medium, compete with the plant and eventually destroy the culture.
In simple terms: the wrong organisms got into your culture.
12.Light & temperature
Temperature affects the plant's metabolism and growth, with many tissue cultures growing well around 20–25 °C.
Light is more species- and stage-dependent, but in vitro plants are generally grown under gentler light than fully established plants. The goal is to provide enough light for development without causing unnecessary stress inside the culture vessel.
13.In vitro vs. Ex vitro
In vitro means growing the plant inside a controlled culture vessel, using a prepared medium and sterile conditions.
Ex vitro means growing the plant outside the vessel, in a normal growing environment.
14.Callus, shoots & roots
Callus is a mass of actively dividing, unspecialized plant cells that can form from an explant under certain culture conditions.
Shoots are new stems and leaves that develop from cultured plant tissue. During multiplication, shoots can be separated and transferred to fresh medium to produce more plants.
Root systems developed by the cultured shoots, either during a separate rooting stage or alongside shoot development. They help prepare the young plants for life outside the culture vessel.
15.Plant growth stage
The growth stage of a plant influences how it responds to tissue culture. Young, actively growing tissue can behave differently from mature tissue, and the requirements can change as the plant moves from establishment → multiplication → rooting.
Choosing the right conditions for each stage helps guide the plant toward the growth we want.
