Residual Effects of Auxin, Chelating Agents, and Metabolic Inhibitors in Cell Extension

The growth-promoting action of auxin on wheat coleoptile segments can be separated from the act of cellular expansion by use of the technique of Cleland and Bonner (1956). The effects of a pretreatment with auxin ("residual effects") in hypertonic mannitol are manifested later when the coleoptiles are transferred to water. Auxin action, but not water uptake, requires aerobic conditions.