HÁJEK, Josef, Angelica CASANOVA-KATNY, Miloš BARTÁK and Jiří SEKERÁK. Cryoresistance of Antarctic endemic lichen Himantormia lugubris: Analysis of photosystem II functionality using a constant-rate cooling approach. Czech Polar Reports. Brno: Masaryk University, 2023, vol. 13, No 1, p. 112-120. ISSN 1805-0689. Available from: https://dx.doi.org/10.5817/CPR2023-1-10.
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Basic information
Original name Cryoresistance of Antarctic endemic lichen Himantormia lugubris: Analysis of photosystem II functionality using a constant-rate cooling approach
Authors HÁJEK, Josef (203 Czech Republic, guarantor, belonging to the institution), Angelica CASANOVA-KATNY, Miloš BARTÁK (203 Czech Republic, belonging to the institution) and Jiří SEKERÁK (203 Czech Republic, belonging to the institution).
Edition Czech Polar Reports, Brno, Masaryk University, 2023, 1805-0689.
Other information
Original language English
Type of outcome Article in a journal
Field of Study 10611 Plant sciences, botany
Country of publisher Czech Republic
Confidentiality degree is not subject to a state or trade secret
WWW URL
Impact factor Impact factor: 1.000 in 2022
RIV identification code RIV/00216224:14310/23:00133088
Organization unit Faculty of Science
Doi http://dx.doi.org/10.5817/CPR2023-1-10
UT WoS 001098584100001
Keywords in English freezing; photosynthetic apparatus; cooling point; King George Island; differential method
Tags rivok
Tags International impact, Reviewed
Changed by Changed by: Mgr. Marie Šípková, DiS., učo 437722. Changed: 18/1/2024 14:47.
Abstract
It is well established that lichens from polar regions of the Earth are capable to perform photosynthesis at sub-zero temperatures. Majority of them show a high degree of cryoresistance, however, species-specific differences exist. Therefore, the aim of our study was to evaluate behaviour of primary photochemical processes of photosynthesis in Antarctic endemic species Himantormia lugubris at sub-zero temperature. For the purpose, the method of constant rate (2 degrees C min-1) cooling (from +20 to-40 degrees C) with simultaneous measurements of chlorophyll fluorescence parameters related to photosystem II (PSII) was used. During the cooling, potential yield of photosynthetic processes in PSII (FV/FM), and effective quantum yield of PSII (phi PSII) were measured in 30 s interval. From the FV/FM and phi PSII data sets, S-curves reflecting temperature dependence of the two chlorophyll fluorescence parameters were constructed and analyzed. The S-curves were found tri-phasic in response to sample temperature decline: (1) slight or no decline phase, (2) rapid decline phase, followed by (3) slow change reaching critical temperature at which the primary photosynthetic processes were fully inhibited. Critical temperature was found-30 and-20 degrees C for FV/FM, and phi PSII, respectively. The latter critical temperature was accompanied by an increase in background chlorophyll fluorescence (F0) indicating inhibition of energy transfer from light-harvesting complexes to core of PSII. A newly-designed chlorophyll fluorescence parameter (a differential, i.e. the difference between the maximum value-normalized FV/FM, and phi PSII) was used in order to evaluate the temperature at which the processes related to photosynthetic electron flow through thylakoid membrane carriers (phi PSII) and the energy flow through PSII (FV/FM) differed to a largest extent. This parameters proved to be temperature-dependent and useful in the evaluation of cryoresistance. Based on our study, H. lugubris, its primary photosynthetic processes in particular, might be considered as higly resistant to sub-zero temperature.
Links
EF16_013/0001708, research and development projectName: ECOPOLARIS - Změny ve struktuře a funkci součástí terestrických polárních ekosystémů (CzechPolar2)
VAN 2023, interní kód MUName: Český antarktický výzkumný program 2023
Investor: Ministry of Education, Youth and Sports of the CR, Czech Antarctic Research Programme 2023, Antarctic research
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