Tissue culture

• Tissue culture refers to the isolation of tissue from the plant body and growing them in an artificial medium under suitable conditions.

• In recent times, It is major and prevalent techniques in crop improvement programs.

• Tissue culture technique is based on the principle of Totipotency. Totipotency is the capacity of a cell to develop into an organism under suitable conditions.

• Steward demonstrated cellular totipotency in tissue culture. He grew small pieces of phloem of carrot root in liquid medium by adding coconut milk. In the culture medium , cells are transformed into root clumps.

• When these clumps were transferred in a semi solid medium, a whole plant was developed with flowers and seeds.

• Haberlandt ,A botanist, was the first to grow isolated plant cells in vitro conditions.

• For tissue culture , A laboratory must be in aseptic condition.

• Cleanliness and sterilization of equipment are very important. Sterilization is usually effected in a hot air oven.

• Although ethanol, Mercuric Chloride and other chemicals are also used for sterilization. The culture medium is also sterilised by the steam under temperature at 100 degree celsius.

• The culture medium is prepared on the basis of plant material to be cultured.

• The medium that is required for tissue culture , contains organic and inorganic salt , vitamin and energy sources.

• Growth regulators such as Auxins, Cytokinin, Gibberellic acid are also added in culture media. 

• White medium , Murashige and skoog medium , Nitsch medium are well known culture media for tissue culture.

• For making of complete media, All the material is added in distilled water. The pH of medium should keep at approximately 6.

• The transfer of plant tissue in the cultural medium should be in septic condition.

• The plant tissue should be washed by mercuric chloride solution and then washed with distilled water to make tissue disinfectant. Chlorine may be used in place of Beautiful chloride for sterilization.

• After transferring the tissue into the culture medium, The culture medium is placed under suitable temperature , pH and light.

• The tissue gives rise to a mass of cell in culture medium. This mass of cell is called callus. Gradually, callus is transformed into an embryo which may finally produce a whole plant.