what is tissue-culture technology?

Answer 1

The thrust of research is to bring the techniques of plant tissue culture and molecular biology in the development of procedures for embryo rescue and regeneration, development of novel hybrids, induction of somatic embryogenesis, micro-propagation of endemic and/ or endangered medicinal plant species, isolation and heterologous expression of genes for the synthesis of biodegradable polymers, and characterization of lignin biosynthesis pathway genes and their down regulation.

Answer 2

The technique or process of keeping tissue alive and growing in a culture medium.
A culture of tissue grown by this technique or process.

tissue culture, the propagation of plants through the placement of small amounts of undifferentiated tissue or single cells in an artificial environment. The tissue is placed in a nutrient medium that favors the production of roots and shoots, and is later planted normally. By using tissue culture, the favorable qualities of plants can be precisely controlled, so that each plant is identical for the particular quality being sought, whether it be disease resistance or plant chemical production.

plant tissue culture
Plant tissue culture, also called micropropagation, 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.
Plant tissue culture relies on the fact that all plant cells have the ability to generate a whole plant (totipotency). Single cells (protoplasts), pieces of leaves, or roots can often be used to generate a new plant on culture media given the required nutrients and plant hormones.

Applications
Plant tissue culture is used widely in plant science; it also has a number of commercial applications. Applications include:

Micropropagation used to produce large numbers of identical individuals, micropropagation is widely used in forestry and in floriculture. Micropropagation can also be used in to conserve rare or endangered plant species.
A plant breeder may use tissue culture to screen cells, rather than plants for advantageous characters, e.g herbicide resistance/tolerance.
Large-scale growth of plant cells in liquid culture in bioreactors as a source of secondary products, like recombinant proteins used as biopharmaceuticals
To cross distantly related species by protoplast fusion and regeneration of the novel hybrid.
To cross-pollinate distantly related species and then tissue culture the resulting embryo which would otherwise normally die (Embryo Rescue)
For production of dihaploid plants from haploid cultures to achieve homozygous lines more rapidly in breeding programmes, usually by treatment with colchicine which causes doubling of the chromosome number.
As a tissue for transformation, followed by either short-term testing of genetic constructs or regeneration of transgenic plants
Certain techniques such as meristem tip culture may be employed that can be used to produce clean plant material from virused stock, such as of potatoes and many species of soft fruit.
Books
There are very few non-scientific books on the subject, but Plants from Test Tubes: Introduction to Micropropagation is aimed at the novice hobbyist or professional grower looking to expand into micropropagation. A practical book on the micropropagation of orchid is Micropropagation of Orchids by Joseph Arditti and Robert Ernst published by John Wiley and Sons.

organ culture
n.
The maintenance or growth of tissues, organ primordia, or the parts or whole of an organ in vitro in such a way as to allow differentiation or preservation of the architecture or function.
A culture of such tissue or such an organ.

Organ culture is a development from tissue culture methods of research, the organ culture is able to accurately model functions of an organ in various states and conditions by the use of the actual in vitro organ itself.


Pieces of an organ or whole organ can be cultured in vitro. The main objective is to maintain architecture of the tissue and direct it towards normal development. In this technique, it is essential that the tissue should never be disrupted or damaged. It requires careful handling. Media used for growing organ culture are generally the same as those used for tissue culture. The techniques or organ culture can be divided into (i) those employing a solid medium and (ii) those employing liquid medium.

Culture of Embryonic organs: Embryonic organ culture is easier than to normal organ from adult animals. Following are the three techniques used for embryo culture.

Organ culture on Plasma clots: It involves the following steps: 1. Prepare a plasma clot by mixing 15 drops of plasma with five drops of embryo extract in a watch glass. 2. Place a watch glass on a pad of cotton wool in Petridish; cotton wool is kept moist to prevent excessive evaporation from the dish. 3. Place a small, carefully dissected piece of tissue on top of the plasma clots in watch glass.

The technique has now been modified, and a raft of lens paper or rayon net is used on which the tissue is placed. Transfer of the tissue can then be achieved by raft easily. Excessive fluid is removed and the net with the tissue placed again on the fresh pool of medium.

Organ Culture on Agar

Media solidified with agar are also used for organ culture and these media consist of 7 parts 1% agar in BSS, 3 parts chick embryo extract and 3 parts of horse serum. Defined media with or without serum also used with agar. The medium with agar provides the mechanical support for organ culture. It does not liquefy. Embryonic organs generally grow well on this medium, bur from adult will not survive.

The culture of adult organs or parts from adult animal is more difficult due to their greater requirement of O2. A variety of adult organs (eg., liver) have been cultured using special media with special apparatus (Towell’s II culture chamber). Since serum was found to be toxic , serum free media were used, and the special apparatus permitted use the use of 95 % oxygen.