Figure 3.

The level of etr1-1 expression from p1002 and p1003 in tomato determines the level of ethylene insensitivity. A, etr1-1 expression in line 2-18 seedlings (containing p1002) or in line 3-16 seedlings (containing p1003) was induced by the concentration of DBAH indicated on medium containing 20 μm ACC. The seedlings were grown in the dark for 10 d. Wild-type seeds (WT) were included as a control. Two representative seedlings are shown for each line. Quantitative measurements for hypocotyl and root lengths with sd are shown in the histograms to the right of each panel. Ten to 20 seedlings were used for each measurement. B, Northern analysis of the seedlings in A. The level of etr1-1 expression in the absence or presence of the inducer at the concentrations indicated was measured, as was the expression of eEF1A to serve as a control for RNA loading. The P values represent the statistical significance between each starred bar relative to the 0-μm DBAH control: * P < 0.001, ** P < 0.005, *** P < 0.05.