Plant Tissue Culture

Definition: The term plant tissue culture is described in vitro and aseptic cultivation of any plant part on nutrient medium.

Fundamental principles: There are three fundamental principles (1) The plant part must be isolated from the rest of plant body. (2) The plant part (ex plant; isolate cell that is not infected) must be in a controlled , preferably defined , nutrient medium. (3) Aseptic condition must be maintained.

Types of plant cultures: (1) Callus Culture. (2) Cell Suspension Culture. (3) Anther Culture. (4) Ovule Culture. (5) Embryo Culture. (6) Protoplast Culture. (7) Micro Propagation.

History: (1) HABERLANDT. (2) WHITE. (3) NOBECOURT. (4) VAN OVERBEEK. (5) SKOOG. (6) BRAUN. (7) STEWARD. (8) MURI.

(1) Callus Culture technique When an excised and isolated piece of tissue is cultured on a nutrient medium, an unorganized mass of cell appears, is called callus. This callus is transferred on to different media to regenerate plants. this technique is called tissue culture.

Plant tissue culture

(2) Cell Suspension Culture It is the culture of isolated cells or very small cell aggregates dispersed in liquid medium. The cell suspension is obtained by agitating pieces of callus in liquid medium on gyrating shaker.

(3) Anther Culture Anther culture is a mean to produce plants with a gametic number of chromosomes by aseptic culture of anther. The technique give rise to haploid plants either directly or through formation of a haploid callus.

(4) Ovule Culture Ovule culture techniques is an important technique in modern plant breeding. it is much easier to culture whole ovule than to isolate a single embryo, especially in small seeded plants. E.g., tobacco

(5) Embryo Culture The embryos are isolated from young seeds and placed on a solid medium containing nutrients and vitamins. Embryos are cultured at 25°c,first in dark until seedlings are about 2 cm long and root formation has started, and than in light until the seedlings can be planted in soil.

(6) Protoplast Culture It is one of the most significant and recent developments in the field of plant tissue culture. the protoplast are usually isolated from cultured cell or leaf mesophyll cell by treating them with enzyme solutions. the isolated protoplast may be used to regenerate the plants directly, or for the production of somatic hybrids through fusion.

(7) Micro Propagation It is in vitro asexual propagation of crop plants. This technique is advantages over the conventional practice of asexual propagation as only a small amount of plant is needed, species highly resistant to conventional bulk propagation can be propagated by this method and it is non season dependent. Micro propagation is used for rapid multiplication of stocks, elimination of diseases, germ plasm preservation, and induction of mutation.

Applications: Tissue culture technique has helped in studying various biochemical and physiological processes in pure cultures without complications of other factors. The effect of various hormones are differentiation and growth processes can be studied by using tissue culture technique. Organogenesis has been studied by inducing formation of roots , shoot tips etc from callus on nutrient medium.