BIBLIOS

Document type
Journal articles

Document subtype
Full paper

Title
Effect of high light on the efficiency of photochemical energy conversion in a variety of lichen species with green and blue-green phycobionts

Participants in the publication
B. Demmig-Adams (Author)
C. Máguas (Author)
Dep. Biologia Vegetal
cE3c
cE3c
W. W. Adams (Author)
A. Meyer (Author)
E. Kilian (Author)
O. L. Lange (Author)

Summary
Exposure to high light induced a quantitatively similar decrease in the rate of photosynthesis at limiting photon flux density (PFD) and of photosystem II (PSII) photochemical efficiency, FV/FM, in both green and blue-green algal lichens which were fully hydrated. Such depressions in the efficiency of photochemical energy conversion were generally reversible in green algal lichens but rather sustained in blue-green algal lichens. This greater susceptibility of blue-green algal lichens to sustained photoinhibition was not related to differences in the capacity to utilize light in photosynthesis, since the light-and CO2-saturated rates of photosynthetic O2 evolution were similar in the two groups. These reductions of PSII photochemical efficiency were, however, largely prevented in lichen thalli which were fully desiccated prior to exposure to high PFD. Thalli of green algal lichens which were allowed to desiccate during the exposure to high light exhibited similar recovery kinetics to those which were kept fully hydrated, whereas bluegreen algal lichens which became desiccated during a similar exposure exhibited greatly accelerated recovery compared to those which were kept fully hydrated. Thus, green algal lichens were able to recover from exposure to excessive PFDs when thalli were in either the hydrated or desiccated state during such an exposure, whereas in blue-green algal lichens the decrease in photochemical efficiency was reversible in thalli illuminated in the desiccated state but rather sustained subsequent to illumination of thalli in the hydrated state.


Where published
Planta

Publication Identifiers
ISSN - 0032-0935

Publisher
Springer Science and Business Media LLC



Document Identifiers
URL - https://link.springer.com/article/10.1007/BF01160396
DOI - https://doi.org/10.1007/BF01160396

Keywords
Chlorophyll fluorescence Chlorophyta Cyanobacteria Desiccation Lichens Light stress Photoinhibition in phycobionts Phycobiont