An aseptic culture is one without contaminating bacteria or fungi. A growing explant can be induced to produce vegetative shoots by including a cytokinin in the medium. A cytokinin is a plant growth regulator that promotes shoot formation from growing plant cells. Rooting or preplant stage. Growing shoots can be induced to produce adventitious roots by including an auxin in the medium.
Auxins are plant growth regulators that promote root formation.
For easily rooted plants, an auxin is usually not necessary and many commercial labs will skip this step. A growing, rooted shoot can be removed from tissue culture and placed in soil. When this is done, the humidity must be gradually reduced over time because tissue-cultured plants are extremely susceptible to wilting. The culture medium is formulated so that it provides all of the compounds needed for plant growth and development, including certain compounds that can be made by an intact plant, but not by an isolated piece of plant tissue. Agar is added if a solid medium is desired.