Features of chlorophyll fluorescence transients can be used to investigate low temperature induced effects on photosystem II of algal lichens from polar regions ( Short Communication )

Abstract

Chlorophyll fluorescence is an effective tool for investigating characteristics of any photosynthesizing organisms and its responses due to different stressors. Here, we have studied a short-term temperature response on three Antarctic green algal lichen species: Umbilicaria antarctica, Xanthoria elegans, and Rhizoplaca melanophtalma. We measured slow chlorophyll fluorescence transients in these Antarctic lichen species during slowely cooling of thallus temperature from 20°C to 5, 0 and-5°C with 20 minute acclimation at each temperature. The measurements were supplemented with saturation pulses for the analysis of chlorophyll fluorescence parameters: maximum yield of PS II photochemistry (F V /F M), effective quantum yield of PS II photochemistry ( PSII) and quenching parameters. In response to decreasing thallus temperature, we observed species-specific changes in chlorophyll fluorescence parameters as well as in the shape of the chlorophyll fluorescence transients. We propose that species-specific changes in the slow phase of chlorophyll fluorescence transients can be potentially used as indicators of freezing stress in photosynthetic apparatus of lichen algal photobionts.

Changes in thermic limits and acclimation assessment for an alpine plant by chlorophyll fluorescence analysis: F_v/F_mvs. R_fd

“…In addition to Rfd values, a complete analysis of the slow phase of chlorophyll fluorescence transients (OPSMT) can be potentially used as indicators of freezing stress in photosynthetic apparatus (Mishra et al, 2015). Apart from thermic stress, it has been previously reported that Rfd is more sensitive to a variety of stress factors than Fv/Fm.…”

Effects of short-term low temperature stress on chlorophyll fluorescence transients in Antarctic lichen species

“…Among a wide spectrum of methods using chlorophyll fluorescence technique in higher plants, slow (Kautsky) chlorophyll fluorescence transient has been used much less frequently then ´traditional´ parameters such a e.g potential (F V /F M ) and effective quantum yield of photosynthetic processes in photosystem II ( PSII ) -Bolhar-Nordenkamf et Oquist (1993). However, complex analysis of ChlF transient was presented by for Arabidopsis thaliana (Mishra et al 2014), and Antarctic lichens (Mishra et al 2015). The latter study suggested usefulness of ChF transient analysis to discriminate physical effects of low temperature on lichens and individual species responses, their tolerance and/or avoidance mechanisms.…”

“…In lichens, slow ChlF transient was used to characterize sensitivity to photoinhibition (e.g. Conti et al 2014) and freezing stress (Mishra et al 2015). Similarly, Nabe et al (2007) studied sorbitol effect on shape of PSMT phase of transient in a liverworth (Marchantia polymorpha) and a moss (Bryum argenteum ).…”

Short-term responses of primary processes in PS II to low temperature are sensitively indicated by fast chlorophyll fluorescence kinetics in Antarctic lichen Dermatocarpon polyphyllizum

“…Fast chlorophyll fluorescence measurement is a useful tool for non-invasive detection of various stress effects, such as e.g. high temperature , Martinazzo et al 2012, low and freezing temperature (Mishra et al 2015), drought (Oukarroum et al 2007 or heavy metal soil contamination (Żurek et al 2014). The chlorophyll fluo-rescence parameters change with different stresses.…”

“…It decreases PS II photochemical efficiency and modifies the values of chlorophyll fluorescence parameters (Smethurst et al 2005). Under the low temperature stress a variable chlorophyll fluorescence is decreased as well as photochemical quenching and effitiency of open PS II reaction centers (Yang et al 2007, Mishra et al 2015. Non-photochemical quenching of absorbed excitation energy increases with decreasing temperature.…”