In the broadest sense, the plant tissue culture is defined as a very heterogeneous set of techniques that have in common the fact that an explant -that is, a separate part of the plant, such as protoplasts , cells , tissues or organs - is aseptically grown in artificial media of defined chemical composition and incubated under controlled environmental conditions. These techniques behind can be used as tools for plant micropropagation , rapid spread of clones , removal of viruses and diseases, production of haploids , protoplast isolation and utilization, embryo culture, production of phytochemicals , genetic engineering , mutation and cell selection, production of synthetic seeds and basic studies of anatomy, development, physiology and plant nutrition. 1 2
Tissue culture starts with the microscopic dissection of the plant under strict hygienic conditions in order to transfer an actively growing tissue (meristematic tissue) with safety and cleanliness in a sterile container without introducing micro pollutants. The cells and tissues grow and develop from the original explant depends on the objectives of tissue culture. In some cases the cells will form a seemingly disorganized mass, known as callus , others will be present other recognizable structures like stems , roots , bulbs or other organs. These tissues grown in vitro are in a microcosm a sterile glass or plastic, protected from the outside environment is not sterile. Is essential to maintain the sterility of the confined environment in the container, since any microorganism that is gained entry to the same opportunistically grow at a rate much faster than the plant tissues and colonize and eventually kill the tissue. In order to maintain the vigor of the plant tissues and allow them to grow, multiply and develop, ie "cultivating the tissues', should be provided in addition to certain external requirements. The fabrics may require that the supports or are placed on or inside the surface of an aqueous gel, solidified with agar or can be placed in a liquid medium. The fabrics also need a supply of mineral elements which are essential nutrients for plant growth, possibly also some vitamins , sugars as energy source and a mixture of plant hormones known to control the growth and development of these particular tissues. For proper growth and development of tissue culture is generally necessary to supply extremely low light, much lower than that of sunlight. Accumulation in plants of the energy from carbohydrates come from sugars added to the culture medium rather than the photosynthesis , so that unnecessary high light levels.

The plant tissue culture is used as a key tool in a number of areas and techniques of research and plant production, all related to what is now known as plant biotechnology . Here are some of the most important:
Basic studies of anatomy, development and plant nutrition.
Somaclonal variation and gametoclonal through cell selection.
Protoplast isolation. Used for cell fusion ( somatic hybridization ) and genetic engineering .
Production of haploid plants through anther culture or pollen culture.
Rescue of fertilized eggs and embryos of interspecific and intergeneric crosses
Genetic Engineering: includes all techniques that use living organisms or their components to produce or modify products. The variety of applications including the areas of energy, environmental management and agricultural and pharmaceutical products.
Micropropagation plants. Clonal spread or spread in vitro and vegetative propagation.
Somatic embryogenesis .
Meristem culture for elimination of viruses and diseases in plants.
Production of phytochemicals or production of substances of secondary metabolism .





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