Figure 2.

Effects of Suc on LFY::GUS expression. A, Plants homozygous for LFY::GUS were grown on media with either 1.5% or 5% (w/v) Suc under LL, until flower buds were visible to the naked eye. Twenty-five to 30 plants were combined and used to measure GUS activity in shoot apices. Protein extracts were prepared as described in “Materials and Methods.” All plants on 1.5% (w/v) Suc medium had produced visible flower buds in the center of shoots on the 18th d, but the main stems had not bolted even by the 21st d. On 5% (w/v) Suc medium, 47% of plants showed visible flower buds by the 24th d and 82% by the 28th d. Black symbols indicate plants that had no flower buds visible to the naked eye at the end of the experiment, and white symbols indicate plants that had flower buds. B, Values of LFY::GUS activity are plotted against the mean values of the number of rosette leaves on plants that had no flower buds, harvested in experiment A. Symbols are the same as in A. GUS activity values are the mean of two measurements. MUG, 4-methylumbelliferyl-β-d-glucuronide. Similar results were obtained in two independent experiments.