Explain how suspension culture is prepared from callus?

Hint:Suspension culture which is also known as cell suspension is a type of culturing the cell where single cells or small aggregates of cells are allowed to multiply in an agitated growth medium leading to the formation of a suspension.

Complete answer
A callus is defined as the mass of growing unorganized plant parenchyma cells. Callus are capable of giving rise to an entire plant by means of organogenesis or embryogenesis. To prepare suspension culture from callus, the callus is transferred to a liquid nutrient medium and agitated that breaks the cells into small fragments. The nutrient medium not only consists of nitrogen, potassium, phosphorus and other elements but also plant growth hormones such as auxin and gibberellin that help in root and shoot development.

The mixture is continuously curbed at 100 to 250 rpm to prevent aggregate formation and also to provide good aeration and mix to the culture. This medium is incubated for growth for sometime following which it is subcultured in a gel like medium. extensive subculturing is required to prevent contamination and allow the culturing process to progress without any hindrance.

Callus culturing is of increased importance not only because it can give rise to an entire plant but also because it can be manipulated genetically. genes can be inserted into the callus and these will give rise to a plant with desired characteristics.

Note:Callus can turn brown and die during the culture process which is caused mostly due to the oxidation of phenolic compounds. This should be prevented otherwise it will lead to a stop in the culturing process.