Fig. 4
Thermal fingerprints of the fungal tissue in the lower cortex of L. pulmonaria discs (Experiment 3). Unlike in Fig. 3, the thallus discs were placed upside down to measure rT of the fungal layer. a Viability staining of "live" and "dead" thallus discs stained with 1% nitroblue tetrazolium (NBT). As actively respiring cells convert NBT to a dark precipitate, only "live" discs show dark staining. b Maximal photochemical efficiency (Fv/Fm) of "live" (green symbols) and "dead" (red symbols) thallus discs at the end of imbibition. Bars labelled with different letters indicate significant differences between treatments (P < 0.05; Kolmogorov–Smirnov test). Bars are means ± SE of (n = 14 lichen discs). c Moisture content (MC) of "live" (green) and "dead" (red) thallus discs during imbibition. Symbols are means ± SE (n = 14 discs). Asterisks indicate significant differences between treatments ("live", "dead") at P < 0.05 (Mann–Whitney U test) at each time-point. d Thermal fingerprints of "live" and "dead" thallus discs, showing median values of relative temperature (rT) during imbibition. Data are medians of n = 14 discs. e Differences between the fingerprints of "live" and "dead" thallus discs (ΔTlive–dead). Green horizontal bars at the bottom of the panel indicate the time windows in which the rT values of "live" and "dead" thallus discs differed significantly (P < 0.05, Two Sample t-test). Open blue horizontal bars indicate the time periods of hydration by water vapour and closed blue bars indicate imbibition in liquid water from below