Pericycle periclinal proliferation in the basal hypocotyl of Arabidopsis Col-0 (wt) and ein3eil1 double mutant seedlings either cultured with ACC (0.1μM), or with JAMe (10 μM) alone or combined with ACC (0.1μM), and without exogenous hormones (hormone-free, HF). Mean radial extension (± Standard Error (SE)) of the vasculature plus pericycle periclinal proliferation in the basal 5 mm of the hypocotyl. Different letters among different treatments within the same genotype, or between the two genotypes within the same treatment, indicate significant differences at least at p < 0.05. The same letters indicate no significant difference. Two-way ANOVA followed by Tukey’s post-test. n = 30.