Vol.:(0123456789) 1 3
Polar Biology
https://doi.org/10.1007/s00300-019-02464-w
ORIGINAL PAPER
Temperature effects on photosynthetic performance of Antarctic
lichen Dermatocarpon polyphyllizum: a chlorophyll fluorescence study
Michaela Marečková
1
· Miloš Barták
1
· Josef Hájek
1
Received: 24 May 2018 / Revised: 17 October 2018 / Accepted: 4 February 2019
© Springer-Verlag GmbH Germany, part of Springer Nature 2019
Abstract
Chlorophyll fluorescence is an important indicator of a photosynthetic energy conversion in chloroplast photosystem II
and responds sensitively to stress factors affecting photosynthesizing organisms. Three different methods were employed
to identify the most sensitive fluorescence parameters responding to thallus temperature decrease within Antarctic lichen
Dermatocarpon polyphyllizum: (1) Fast chlorophyll fluorescence transient (OJIP with parameters characterizing photosystem
II functioning) (2) Slow Kautsky kinetics supplemented by saturation pulses (to evaluate quantum yield of photosynthetic
processes in photosystem II, as well as maximum quantum PSII efficiency and non-photochemical and photochemical
quenching), and (3) Linear cooling from + 22 to − 40 °C (to determine change in Φ
PSII
and the critical temperature for PSII).
A K-step (usually documented at highly stressed organisms) was found in OJIPs measured at + 22 °C at 0.22–0.40 ms and
attributed to the negative effect of high temperature on PSII functioning, PSII donor side limitation in particular. At subzero
temperature (− 0.5, − 5 °C), an L-step was detected at 0.05 ms and related to a low temperature-induced decrease in con-
nectivity between light-harvesting complexes and PSII. An increase of DI
0
/RC (the flux of dissipated excitation energy) was
reported for the first time in lichens. The OJIP-derived parameters, DI
0
/RC and Phi_D
0
(quantum yield of energy dissipation)
in particular, indicated that they might be used for the detection of early events in low temperature-affected lichens. Linear
cooling data determined the critical temperature (− 12 °C) for primary photosynthetic processes (Φ
PSII
) in Dermatocarpon.
Keywords Diplosphaera sp. · OJIP · K-step · Kautsky kinetic · Linear cooling · Photosystem II
Abbreviations
ChlF Chlorophyll fluorescence
DA Dark adapted
KK Kautsky kinetics
LA Light adapted
LHC Light-harvesting complexes
OJIP Fast chlorophyll fluorescence transient
PI Performance (vitality) Index
PS Photosystem
RC Reaction center
Introduction
Lichens from polar regions are well adapted to low tem-
perature and able to photosynthesize even at subzero tem-
peratures. Primary photosynthetic processes related to PSII
and a chloroplast thylakoid membrane are still effective at
freezing temperatures, as reported by several chlorophyll
fluorescence studies in polar lichens (Barták et al. 2007;
Hájek et al. 2016; Míguez et al. 2017). This is because of
several adaptive mechanisms, such as and including osmoti-
cally active compounds that decrease the freezing point of
the cytoplasm and ice-nucleation proteins preventing the
creation of ice crystals with sharp edges that could damage
the cell organelles.
Chlorophyll fluorescence (ChlF) is a non-invasive method
resulting in numerous indicators of photosynthetic energy
conversion. Temperature response curves of chlorophyll flu-
orescence parameters are routinely used throughout the Plant
Kingdom. In lichens, the effect of low and freezing tempera-
ture on chlorophyll fluorescence parameters has been studied
as well (see e.g. Hájek et al. 2016). Despite the fact that
* Josef Hájek
jhajek@sci.muni.cz
1
Department of Plant Physiology and Anatomy, Institute
of Experimental Biology, Masaryk University, Kotlářská 2,
61137 Brno, Czech Republic