In this article we will discuss about the role of auxins and cytokinins in culture medium.
Effective, speedy growth and desirable morphogenesis in tissue culture requires the presence of both auxins and cytokinins in culture medium. The relative concentration of auxins and cytokinins are often essential to bring about some kind of morphogenesis.
Axillary shoot proliferation in some species may be promoted by the presence of auxin along with cytokinin. In several plants, organogenesis was possible by transferring cells to the media containing high cytokinin to low auxin.
Initiation of adventitious buds and roots seem to require balance between auxin and cytokinin in culture media. Possibilities of profuse cell induction have been evidenced in dicots under the influence of equal concentrations of auxin and cytokinin.
In micro-propagation industries, mass multiplication of plants by axillary shoot proliferation is preferred to other shoot induction methods. Very high cytokinin to low auxin ratio in culture media provides optimum result in most of the species (Fig. 6.3).