Figure 10.

ETR1 and EIN4 both function in ACC-induced root hair initiation and elongation. ACC induces root hair formation and elongation through specific ethylene receptors. Four-day-old seedlings were treated with 1 µm ACC for 24 h. The number of root hairs is shown on the left and the length of root hairs shown on the right, with representative images for each genotype and treatment. Averages and se are reported for 12 to 18 seedlings. ^aSignificant difference between control and treatment with ACC within a genotype, at P < 0.05; ^bsignificant difference between parental lines and mutant genotypes.