Figure 3.

In the axr1-12 mutant, leaves initiate in the dark, this being enhanced by the addition of cytokinin. A, Seedlings of the Columbia wild type (WT) and axr1-12 were germinated and grown in the dark for 5 d, on 1% Suc-containing medium with or without BAP at the concentrations indicated, or for the wild type in the light for 5 d on medium without BAP. The area of one of the first two leaf primordia is indicated. Error bars represent se. Asterisks reflect the significance of differences between axr1 and the wild type. B to F, Images of leaf primordia of representative shoot apical regions of seedlings as in A. B to D, The wild type. E and F, The axr1-12 mutant. B and E, Dark, no BAP. C and F, Dark, 10 µm BAP. D, Light. Bar = 200 µm.