fhy3-1 does not impair seed germination. Seeds of WT, phyA, and fhy3 were incubated in darkness at 4°C and either transferred to darkness (black bars), hourly FR (shaded bars), continuous FR (white bars), or hourly R (hatched bars) at 25°C (A) or incubated in darkness 24 h at 25°C, given a single pulse predicted to establish a series of calculated Pfr/P, and returned to darkness (B). Data are means and se of 12 replicate boxes. ▪, WT; ▴, phyA; ▾, fhy3.