Types of culture

Abstract

A plant consists of different organs, each being composed of different tissues, which in turn are made up of individual cells. If the cell walls of these cells are enzymatically digested, protoplasts are produced. Just as there are many different building materials within a plant, there are many different types of in vitro culture:

• 1. Culture of intact plants: a seed may be sown in vitro from which a seedling, and finally a plant develops e.g. orchids (Fig. 4.1.).

• 2. Embryo culture: here an isolated embryo is grown after removal of the seed coat.

• 3. Organ culture: an isolated organ is grown in vitro. Different types can be distinguished e.g. meristem culture, shoot-tip culture, root culture, anther culture, etc. Often a part (tissue mass, organ) which has been isolated from a plant is referred to as an expiant and the culture of this is an expiant culture.

• 4. Callus culture: if a differentiated tissue is isolated, allowed to dedifferentiate in vitro and a so-called callus tissue produced, the process is termed callus culture.

• 5. Single-cell culture: the growing of individual cells which have been obtained from a tissue, callus or suspension culture, with the aid of enzymes or mechanically.

• 6. Protoplast culture: the culture of protoplasts obtained from cells by enzymatic digestion of the cell wall.