Figure 5.

Expression Pattern of Pn FT1 and Pn FT2 mRNAs in Two Pharbitis Cultivars Reflects the Differences in Their Critical Night Length.

(A) Quantification of Pn FT1 and Pn FT2 transcript levels in cv Violet and Kidachi under 15 h light/9 h dark at 25°C. Cotyledons were harvested every 2 h for the first 12 h on day 5. Solid line, Kidachi; dotted line, Violet.

(B) Quantification of Pn CO transcript levels in cv Violet and Kidachi. Samples were harvested as in (A). Solid line, Kidachi; dotted line, Violet.

(C) Flowering times of Violet and Kidachi under 15 h light/9 h dark. Flower buds present at the first 15 nodes of the main axis were counted 4 weeks after the start of the experiment. Twenty-two plants of each cultivar were used.

(D) and (E) Pn FT1 and Pn FT2 expression in Violet and Kidachi after the shift to continuous darkness (DD). Plants were grown under 10 h light/14 h dark for 6 d and then transferred to DD. Cotyledons were harvested every 2 h for 60 h. RT-PCR was performed to detect Pn FT1, Pn FT2, and ubq. Solid line, Kidachi; dotted line, Violet.

(F) Pn CO expression in Violet and Kidachi after the shift to continuous darkness (DD). Analysis performed as described for (D) and (E). Solid line, Kidachi; dotted line, Violet. Error bars show se of three PCR experiments. A biological replicate provided a similar result.