Figure 8.
Effect of redox and osmotic treatments on shoot apex morphology and peroxide content. Apices were isolated at the end of the 3-week recovery phase to check the effect of the treatments on the vegetative/generative transition (first and third rows). The peroxide content was detected with the green fluorescent dye H2DCFDA (second and fourth rows). The various compounds were applied to 12-day-old seedlings of Ch and Tsp at 20/17°C for 3 days and subsequently at 5°C during the first 4 days of the 3-week cold hardening period, which was followed by a 3-week recovery period at 20/17°C. Photos of the apices after the other treatments can be seen in Additional file 5. The numbers on the native photos indicate the developmental stage of the flower primordia according to the following scale: 0 – vegetative apex, 1 – start of apex elongation, 2 – elongation with single ridge, 3 – double ridge indicating the vegetative/generative transition, 4 – enlargement of spikelet primordia, 5 – empty glume primordia [51]. The bars indicate 200 μm.