2016
Sensitivity of photosynthetic processes to freezing temperature in extremophilic lichens evaluated by linear cooling and chlorophyll fluorescence
HÁJEK, Josef, Miloš BARTÁK, Jana HAZDROVÁ a Marie FORBELSKÁZákladní údaje
Originální název
Sensitivity of photosynthetic processes to freezing temperature in extremophilic lichens evaluated by linear cooling and chlorophyll fluorescence
Autoři
HÁJEK, Josef (203 Česká republika, garant, domácí), Miloš BARTÁK (203 Česká republika, domácí), Jana HAZDROVÁ (203 Česká republika, domácí) a Marie FORBELSKÁ (203 Česká republika, domácí)
Vydání
Cryobiology, Academic Press, 2016, 0011-2240
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10600 1.6 Biological sciences
Stát vydavatele
Spojené státy
Utajení
není předmětem státního či obchodního tajemství
Impakt faktor
Impact factor: 1.996
Kód RIV
RIV/00216224:14310/16:00091424
Organizační jednotka
Přírodovědecká fakulta
UT WoS
000389010600005
Klíčová slova anglicky
Usnea antarctica; Usnea aurantiaco-atra; Umbilicaria cylindrica; cryoresistance; Antarctica; James Ross Island; temperature stress
Příznaky
Mezinárodní význam, Recenzováno
Změněno: 13. 4. 2017 21:54, Ing. Andrea Mikešková
Anotace
V originále
Extremophilic lichens and their photosynthesizing photobionts from the cold regions of Earth are adapted to perform photosynthesis at subzero temperatures. To evaluate interspecific differences in the critical temperature for primary photochemical processes of photosynthesis, we exposed lichen thalli of Usnea antarctica, Usnea aurantiaco-atra, and Umbilicaria cylindrica to linear cooling from +20 to minus 50 °C at a constant rate of 2 °C/min. Simultaneously, two chlorophyll fluorescence parameters (FV/FM: potential yield of photosynthetic processes in photosystem II, YieldPSII: effective quantum yield of PS II) evaluating a gradual subzero temperature-induced decline in photosynthetic processes were measured by a modulated fluorometer. For the studied species, the response of FV/FM and YieldPSII to declining temperature showed an S-curve shape. The decline in FV/FM and YieldPSII at low temperatures started at minus 5 and +5 °C, respectively in the majority of cases. The decline was, however, species-specific. U. aurantiaco-atra showed a constant-rate decline of YieldPSII from the physiological temperature 20 °C. U. antarctica exhibited the first sign of FV/FM decline at minus 12 °C. The critical temperature related to full inhibition of the photosynthetic processes in PSII (FV/FM), was found at minus 20 °C. However, this occurred at minus 30 °C for U. cylindrica. In an individual sample, the critical temperature for FV/FM was typically lower than for YieldPSII. The method of linear cooling combined with simultaneous measurements of chlorophyll fluorescence parameters proved to be an efficient tool in the estimation of extremophilic species sensitivity/resistance to freezing.
Návaznosti
LM2010009, projekt VaV |
| ||
LM2015078, projekt VaV |
|