Effects of end-of-day treatments of P.
nil seedlings with red and far-red light on flowering and
PNZIP mRNA accumulation during the dark. Seedlings were
grown in continuous light for 6 d, and just before the transition
to darkness at 0 h they were exposed for 10 min to red (R),
far-red (FR), far-red and then red (FR/R), or red and afterward far-red
(R/FR) light. A, Effects of end-of-day treatments on flower induction
as measured after 3 weeks. Error bars indicate ses. B, RNA
gel-blot hybridization analysis of PNZIP mRNA levels
detected 4 and 14 h after the end-of-day treatments. Each lane
contained 30 μg of cotyledon total RNA. A photograph of the amount of
rRNA served as a control for equal loading of RNA in each lane. Numbers
on the right indicate the approximate sizes of the mRNAs detected. The
black and white bar at the bottom of the figure schematically presents
the light/dark conditions and the timings of light treatments and RNA
isolation.