Abstract
In order to clarify the role of symbiotic association in drought tolerance of photosynthetic partners in lichens, responses to air-drying treatments in a green-algal lichen (Ramalina yasudae Rasanen) and its green algal photobiont (Trebouxia sp.) were studied. Responses to dehydration in the isolated Trebouxia sp. were different from those in the lichen. R. yasudae. Dehydration induced quenching of PS II fluorescence (d-NPQ) was less in the isolated Trebouxia sp. compared with that in R. yasudae, suggesting that a substance(s) or a mechanism(s) to dissipate absorbed light energy to heat was lost by the isolation of the photobiont, and the air-dried isolated Trebouxia sp. showed a higher sensitivity to photoinhibition than R. yasudae. We assayed the effects of various substances extracted from R. yasudae thalli on the fluorescence of Trebouxia sp. And we found the d-NPQ-type fluorescence quenching in the Trebouxia sp. was accelerated if they were dried with arabitol which was the main component of the water extract of R. yasudae. These results support the idea that arbitol triggered the photoprotection mechanism under drought conditions of the photobiont symbiotic with the mycobionts.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
