Micro propagation (tissue culture or in-vitro culture) refers to the multiplication of plants, in aseptic condition and in artificial growth medium. From very small plant parts like Meristem tip, callus embryos, anther etc. the German plant physiologist heberland 9 1902 0 first described the biological principles of tissue and organ culture. After that rapid advantages have been made in plant tissue culture. At present tissue culture finds extensive application in agriculture and horticulture in several countries. Though some achievements have been made but the commercial utilization of the techniques of tissue culture is still lacking behind.
Merits of Micro Propagation:
1. Tissue culture helps in rapid multiplication of true plats throughout the year.
2. A new plant can be regenerated from a miniature plant part, whereas in conventional methods a shoot of considerable length is required.
3. Large number of plants can be produced in culture tubes in small space with uniform growth and productivity of growing them in large area in nursery.
4. Plants raised by tissue culture are free from diseases.
5. Tissue culture coupled with somatic hybridization helps in evolving new cultivar in a short time.
6. Micro propagation facilitates long distance transport of propagation material and long term storage of clonal materials.
7. Tissue culture methods are not viable (male sterile) or not available easily (e.g. banana ) and in plant where propagation by conventional methods are expensive ( e.g. orchid ).
Demerits of Micro Propagation:
1. The cost involved in setting up and maintence of laboratory is very high and may not justify their use in all the horticultural plants ordinarily.
2. Tissue culture techniques require skill and manpower.
3. Slight infection may damage the entire lot of plants.
4. Some genetic modification (mutation) of the plant may develop with some varieties and culture systems which may alter the quality of the produce.
5. The seedling grown under artificial condition may not survive when placed under environmental condition directly if thing is not given.