Comparison of Physiological Activities Between Coronatine and Indole-3-Acetic Acid to Some Plant Tissues

Abstract

The physiological activities of coronatine on water uptake in potato tuber, root elongation in wheat and hypocotyl elongation in mung beans were compared with those of indol-3-acetic acid (IAA). In potato tuber discs the stimulation of water uptake by coronatine was considerably higher that of IAA. The elongation of etiolated hypocotyl segments was slightly affected by coronatine, while markedly stimulated by IAA. Therefore, coronatine appears to lack the typical activity of auxin to elongate mung bean hypocotyl segments. Coronatine and IAA showed similar effects on root elongation in wheat. Therefore, coronatine appears to have the typical ability of auxin to inhibit root elongation. These results on physiological studies of coronatine suggest that coronatine may be claimed to have a tissue specificity clearly different from that of IAA.