IAA and PEO-IAA induce protoplast expansion, and 5-F-IAA does not. A, Protoplasts were treated with 10 µm IAA or the same concentration of PEO-IAA or 5-F-IAA or buffer as a control at 0 min (indicated by the arrow). IAA and PEO-IAA induced a similar increase in net volume. Results are averages ± se from a minimum of n = 5 protoplasts from two independent experiments. B, Competition experiments with 5-F-IAA plus PEO-IAA and 5-F-IAA plus 5-F-IAA treatment. First, 10 µm 5-F-IAA was applied at 0 min (first arrow). The second application is indicated by the second arrow at 15 min. PEO-IAA (10 µm) still induced protoplast swelling when 5-F-IAA was applied first. As a control, buffer was applied at the second time point. Values are means ± se from a minimum of n = 7 protoplasts from two independent experiments.