Fig. 5

Confocal fluorescence and transmission images showing qualitative concentrations (fluorescence intensity) and location of phenolic compounds within cells and cell walls of red varieties of Antarctic B. pseudotriquetrum, C. purpureus and S. antarctici at week 0 and after 2 weeks of growth in the laboratory (green samples, conditions as in Fig. 4). Leaves were stained with Naturstoff reagent A and fluorescence images were captured in the 500–530 nm emission window under the same confocal settings. Yellow/orange fluorescence indicates the presence and concentration of phenolic compounds. Scale bars are 25 μm