Plant tissue culture is a practice used to propagate plants under sterile conditions, often to produce clones of a plant. Different techniques in plant tissue culture may offer certain advantages over traditional methods of propagation, including :
The production of exact copies of plants that produce particularly good flowers, fruits, or have other desirable traits.
To quickly produce mature plants.
The production of multiples of plants in the absence of seeds or necessary pollinators to produce seeds.
The regeneration of whole plants from plant cells that have been genetically modified.
The production of plants in sterile containers that allows them to be moved with greatly reduced chances of transmitting diseases, pests, and pathogens.
The production of plants from seeds that otherwise have very low chances of germinating and growing, i.e.: orchids and nepenthes.
To clean particular plant of viral and other infections and to quickly multiply these plants as 'cleaned stock' for horticulture and agriculture.
In 1902, with this question in mind, the German plant physiologist Gottlieb Haberlandt attempted to culture (grow) isolated plant cells under sterile conditions on an artificial growth medium. Although his cultured cells never underwent cell division under these "in vitro" (in glass) conditions, Haberlandt is credited with originating the concept of cell culture.
GEORGE MICHEL MOREL (1916-1973), a plant physiologist at the National Institute for Agronomic Research in France, was one of many scientists who had become interested in the formation of tumors in plants as well as in studying various pathogens such as fungi and viruses that cause plant disease. He was successful in culturing tissue from ferns and was the first to culture monocot plants. He utilized a small piece of the growing tip of a plant shoot (the shoot apex) as the starting tissue material. This tissue was placed in a glass tube, supplied with a medium containing specific nutrients, vitamins, and plant hormones, and allowed to grow in the light. Under these conditions, the apex tissue grew roots and buds and eventually developed into a complete plant. He was able to generate whole plants from pieces of the shoot apex that were only 100 to 250 micrometers in length. He also investigated the growth of parasites such as fungi and viruses in dual culture with host-plant tissue. Using results from these studies and culture techniques that he had mastered, Morel and his colleague Claude Martin regenerated virus-free plants from tissue that had been taken from virally infected plants. He was the first to recognize the potential of the in vitro culture methods for the mass propagation of plants. He estimated that several million plants could be obtained in one year from a single small piece of shoot-apex tissue. Plants generated in this manner were clonal (genetically identical organisms prepared from a single plant). In vitro techniques have truly revolutionized agriculture.
Plant tissue culture relies on the fact that many plant cells have the ability to regenerate a whole plant (totipotency). Single cells, plant cells without cell walls (protoplasts), pieces of leaves, or (less commonly) roots can often be used to generate a new plant on culture media given the required nutrients and plant hormones.
