Molecular genetics of auxin and cytokinin

Abstract

The indeterminate nature of plant development requires that plants continuously regulate cell division and elongation in response to genetic, as well as a wide variety of different environmental signals [53]. Since their discovery, many physiological studies have shown that the plant hormones auxin and cytokinin have fundamental roles in the regulation of cell growth [30, 43]. Both compounds appear to be essential for growth of plant cells in culture. Organogenesis in tissue culture is regulated by altering the concentration of auxin and cytokinin. In the intact plant, auxin and cytokinin are apparently involved in a bewildering array of growth processes. One explanation for this complexity is that most and perhaps all changes in cell division or elongation are mediated by cytokinin or auxin. According to this view, developmental responses to environmental stimuli such as light or temperature are mediated by these hormones.