Currently, tissue cultures of species of agricultural importance have wide applicability in industrial production processes. Tissue culture is a name given to a set of techniques that allow the regeneration of cells, tissues and organs of plants, from segments of plant organs or tissues, using nutrient solutions in aseptic and controlled environment. This regeneration is based on the totipotency of plant cells. Totipotency is a capability indicating that plant cells, in different times, may express the potential to form a new multicellular individual. Tissue culture appears to be a good alternative to conventional propagation, requiring less physical space, with high multiplication rate, without incidence of pests and diseases during cultivation, and enabling higher control of the variables involved. Thus, in the in vitro environment, with the required stimuli and appropriate conditions, different cell types express different behaviors, possibly leading to cell multiplication and differentiation into a specific tissue, characterized by a form and a function, which may lead to the regeneration of a new individual.
The discovery of this feature in plant cells is indistinguishable from the first studies on tissue culture in the early twentieth century by Heberlandt in 1902, which were followed by
the first practical results reported by White in 1934 [1].
Over the years, various tissue culture techniques were developed, being micropropagation, meristem culture and somatic embryogenesis, the most used. The degree of success of any technology employing cultured cells, plant tissues or organs, is mainly dependent on the choice of the nutritional components and growth regulators which control, in a large extent, the developmental in vitro pattern. Therefore, it is crucial to evaluate the nutritional and metabolic needs of cells and tissues of each species to be cultivated. In general, the choice of the medium is carried out taking into account, in addition to these needs, the purpose of the in vitro cultivation, maximizing plant development.
In general, the culture medium is composed of inorganic salts, reduced nitrogen compounds, a carbon source, vitamins and amino acids. Other compounds may be added for specific purposes, such as plant growth regulators, gelling agents, organic nitrogen compounds, organic acids and plant extracts.
Throughout the history of tissue culture, various kinds of culture media have been developed. However, the MS (Murashige & Skoog) medium [2] is the most widely used for the regeneration of dicots, and therefore it has a great importance in the applications of tissue culture in agriculture.
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