Comparison of IAA-Induced and Low Temperature-Induced GA(3) Responsiveness and alpha-Amylase Production by GA(3) Insensitive Dwarf Wheat Aleurone.

Rht3-containing gibberellic acid (GA(3)) insensitive deembryonated wheat (Triticum aestivum L. var Cappelle Desprez x Minister Dwarf) aleurone, that can be made responsive to GA(3) by low temperature, can also be rendered GA(3) sensitive by preincubation with indoleacetic acid (IAA). The IAA-induced response of the dwarf selection is concentration-dependent, relatively sensitive, and similar in magnitude to that induced by low temperature. Other auxins also induce GA(3) responsiveness to a greater or lesser degree. IAA has no apparent effect on the wild type (rht, tall) selection.