Figure 6.

Ethylene regulation of hypocotyl elongation in control and low blue light. A, Ethylene evolution from control light-exposed and low blue light-exposed seedlings is similar. FW, Fresh weight. B, Exogenous application of the ethylene precursor ACC stimulates hypocotyl elongation. C, Ethylene-insensitive mutants have a slightly reduced hypocotyl elongation response to low blue light conditions. Data are means ± se (n = 3 for A, n = 30–50 for B and C). Different letters indicate significant differences.