1
|
Solhaug KA, Eiterjord G, Løken MH, Gauslaa Y. Non-photochemical quenching may contribute to the dominance of the pale mat-forming lichen Cladonia stellaris over the sympatric melanic Cetraria islandica. Oecologia 2024; 204:187-198. [PMID: 38233688 PMCID: PMC10830725 DOI: 10.1007/s00442-023-05498-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 12/10/2023] [Indexed: 01/19/2024]
Abstract
The mat-forming fruticose lichens Cladonia stellaris and Cetraria islandica frequently co-occur on soils in sun-exposed boreal, subarctic, and alpine ecosystems. While the dominant reindeer lichen Cladonia lacks a cortex but produces the light-reflecting pale pigment usnic acid on its surface, the common but patchier Cetraria has a firm cortex sealed by the light-absorbing pigment melanin. By measuring reflectance spectra, high-light tolerance, photosynthetic responses, and chlorophyll fluorescence in sympatric populations of these lichens differing in fungal pigments, we aimed to study how they cope with high light while hydrated. Specimens of the two species tolerated high light equally well but with different protective mechanisms. The mycobiont of the melanic species efficiently absorbed excess light, consistent with a lower need for its photobiont to protect itself by non-photochemical quenching (NPQ). By contrast, usnic acid screened light at 450-700 nm by reflectance and absorbed shorter wavelengths. The ecorticate usnic species with less efficient fungal light screening exhibited a consistently lower light compensation point and higher CO2 uptake rates than the melanic lichen. In both species, steady state NPQ rapidly increased at increasing light with no signs of light saturation. To compensate for less internal shading causing light fluctuations with a larger amplitude, the usnic lichen photobiont adjusted to changing light by faster induction and faster relaxation of NPQ rapidly transforming excess excitation energy to less damaging heat. The high and flexible NPQ tracking fluctuations in solar radiation probably contributes to the strong dominance of the usnic mat-forming Cladonia in open lichen-dominated heaths.
Collapse
Affiliation(s)
- Knut Asbjørn Solhaug
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432, Ås, Norway
| | - Gaute Eiterjord
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432, Ås, Norway
| | - Martine Hana Løken
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432, Ås, Norway
| | - Yngvar Gauslaa
- Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432, Ås, Norway.
| |
Collapse
|
2
|
Barták M, Hájek J, Halıcı MG, Bednaříková M, Casanova-Katny A, Váczi P, Puhovkin A, Mishra KB, Giordano D. Resistance of Primary Photosynthesis to Photoinhibition in Antarctic Lichen Xanthoria elegans: Photoprotective Mechanisms Activated during a Short Period of High Light Stress. PLANTS (BASEL, SWITZERLAND) 2023; 12:2259. [PMID: 37375884 DOI: 10.3390/plants12122259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 06/05/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023]
Abstract
The Antarctic lichen, Xanthoria elegans, in its hydrated state has several physiological mechanisms to cope with high light effects on the photosynthetic processes of its photobionts. We aim to investigate the changes in primary photochemical processes of photosystem II in response to a short-term photoinhibitory treatment. Several chlorophyll a fluorescence techniques: (1) slow Kautsky kinetics supplemented with quenching mechanism analysis; (2) light response curves of photosynthetic electron transport (ETR); and (3) response curves of non-photochemical quenching (NPQ) were used in order to evaluate the phenomenon of photoinhibition of photosynthesis and its consequent recovery. Our findings suggest that X. elegans copes well with short-term high light (HL) stress due to effective photoprotective mechanisms that are activated during the photoinhibitory treatment. The investigations of quenching mechanisms revealed that photoinhibitory quenching (qIt) was a major non-photochemical quenching in HL-treated X. elegans; qIt relaxed rapidly and returned to pre-photoinhibition levels after a 120 min recovery. We conclude that the Antarctic lichen species X. elegans exhibits a high degree of photoinhibition resistance and effective non-photochemical quenching mechanisms. This photoprotective mechanism may help it survive even repeated periods of high light during the early austral summer season, when lichens are moist and physiologically active.
Collapse
Affiliation(s)
- Miloš Barták
- Laboratory of Photosynthetic Processes, Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Josef Hájek
- Laboratory of Photosynthetic Processes, Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Mehmet Gökhan Halıcı
- Fen Edebiyat Fakültesi, Biyoloji Bölümü (Department of Biology), Erciyes Üniversitesi (Erciyes University), 38039 Kayseri, Turkey
| | - Michaela Bednaříková
- Laboratory of Photosynthetic Processes, Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Angelica Casanova-Katny
- Laboratory of Plant Ecophysiology and Climate Change, Environmental Sciences Department, Faculty of Natural Resources, Catholic University of Temuco, Avenida Rudecindo Ortega 02950, Campus San Juan Pablo II, Temuco 481 1123, Chile
| | - Peter Váczi
- Laboratory of Photosynthetic Processes, Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Anton Puhovkin
- Laboratory of Photosynthetic Processes, Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
- State Institution National Antarctic Scientific Center, Ministry of Education and Science of Ukraine, T. Shevchenko blvrd. 16, 01601 Kyiv, Ukraine
- Department of Reproductive System Cryobiology, Institute for Problems of Cryobiology and Cryomedicine, National Academy of Sciences of Ukraine, Pereyaslavska Str. 23, 61016 Kharkiv, Ukraine
| | - Kumud Bandhu Mishra
- Laboratory of Photosynthetic Processes, Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
- Laboratory of Ecological Plant Physiology, Czech Academy of Sciences, Global Change Research Institute, Bělidla 4a, 603 00 Brno, Czech Republic
| | - Davide Giordano
- Laboratory of Photosynthetic Processes, Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| |
Collapse
|
3
|
Lorenz C, Bianchi E, Poggiali G, Alemanno G, Benesperi R, Brucato JR, Garland S, Helbert J, Loppi S, Lorek A, Maturilli A, Papini A, de Vera JP, Baqué M. Survivability of the lichen Xanthoria parietina in simulated Martian environmental conditions. Sci Rep 2023; 13:4893. [PMID: 36966209 PMCID: PMC10039903 DOI: 10.1038/s41598-023-32008-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 03/21/2023] [Indexed: 03/27/2023] Open
Abstract
Xanthoria parietina (L.) Th. Fr. is a widely spread foliose lichen showing high tolerance against UV-radiation thanks to parietin, a secondary lichen substance. We exposed samples of X. parietina under simulated Martian conditions for 30 days to explore its survivability. The lichen's vitality was monitored via chlorophyll a fluorescence that gives an indication for active light reaction of photosynthesis, performing in situ and after-treatment analyses. Raman spectroscopy and TEM were used to evaluate carotenoid preservation and possible variations in the photobiont's ultrastructure respectively. Significant differences in the photo-efficiency between UV irradiated samples and dark-kept samples were observed. Fluorescence values correlated with temperature and humidity day-night cycles. The photo-efficiency recovery showed that UV irradiation caused significant effects on the photosynthetic light reaction. Raman spectroscopy showed that the carotenoid signal from UV exposed samples decreased significantly after the exposure. TEM observations confirmed that UV exposed samples were the most affected by the treatment, showing chloroplastidial disorganization in photobionts' cells. Overall, X. parietina was able to survive the simulated Mars conditions, and for this reason it may be considered as a candidate for space long-term space exposure and evaluations of the parietin photodegradability.
Collapse
Affiliation(s)
- Christian Lorenz
- Department of Biology, University of Florence, Via la Pira 4, 50121, Florence, Italy
| | - Elisabetta Bianchi
- Department of Biology, University of Florence, Via la Pira 4, 50121, Florence, Italy
| | - Giovanni Poggiali
- LESIA-Observatoire de Paris, CNRS, Université PSL, Sorbonne Université, Université de Paris, 5 Place Jules Janssen, 92190, Meudon, France
- INAF-Astrophysical Observatory of Arcetri, Largo E. Fermi 5, 50125, Florence, Italy
| | - Giulia Alemanno
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Renato Benesperi
- Department of Biology, University of Florence, Via la Pira 4, 50121, Florence, Italy
| | - John Robert Brucato
- INAF-Astrophysical Observatory of Arcetri, Largo E. Fermi 5, 50125, Florence, Italy.
| | - Stephen Garland
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Jörn Helbert
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Stefano Loppi
- Department of Environmental Sciences, University of Siena, Via P. A. Mattioli 4, 53100, Siena, Italy
| | - Andreas Lorek
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Alessandro Maturilli
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| | - Alessio Papini
- Department of Biology, University of Florence, Via la Pira 4, 50121, Florence, Italy
| | - Jean-Pierre de Vera
- Microgravity User Support Center (MUSC), Space Operations and Astronaut Training, German Aerospace Center (DLR), Linder Höhe, 51147, Cologne, Germany
| | - Mickaël Baqué
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Ruthefordstraße 2, 12489, Berlin, Germany
| |
Collapse
|
4
|
Valim HF, Dal Grande F, Otte J, Singh G, Merges D, Schmitt I. Identification and expression of functionally conserved circadian clock genes in lichen-forming fungi. Sci Rep 2022; 12:15884. [PMID: 36151124 PMCID: PMC9508176 DOI: 10.1038/s41598-022-19646-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 08/31/2022] [Indexed: 12/02/2022] Open
Abstract
Lichen-forming fungi establish stable symbioses with green algae or cyanobacteria. Many species have broad distributions, both in geographic and ecological space, making them ideal subjects to study organism-environment interactions. However, little is known about the specific mechanisms that contribute to environmental adaptation in lichen-forming fungi. The circadian clock provides a well-described mechanism that contributes to regional adaptation across a variety of species, including fungi. Here, we identify the putative circadian clock components in phylogenetically divergent lichen-forming fungi. The core circadian genes (frq, wc-1, wc-2, frh) are present across the Fungi, including 31 lichen-forming species, and their evolutionary trajectories mirror overall fungal evolution. Comparative analyses of the clock genes indicate conserved domain architecture among lichen- and non-lichen-forming taxa. We used RT-qPCR to examine the core circadian loop of two unrelated lichen-forming fungi, Umbilicaria pustulata (Lecanoromycetes) and Dermatocarpon miniatum (Eurotiomycetes), to determine that the putative frq gene is activated in a light-dependent manner similar to the model fungus Neurospora crassa. Together, these results demonstrate that lichen-forming fungi retain functional light-responsive mechanisms, including a functioning circadian clock. Our findings provide a stepping stone into investigating the circadian clock in the lichen symbiosis, e.g. its role in adaptation, and in synchronizing the symbiotic interaction.
Collapse
Affiliation(s)
- Henrique F Valim
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325, Frankfurt am Main, Germany. .,LOEWE Center for Translational Biodiversity Genomics (TBG), Senckenberganlage 25, 60325, Frankfurt am Main, Germany.
| | - Francesco Dal Grande
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325, Frankfurt am Main, Germany.,LOEWE Center for Translational Biodiversity Genomics (TBG), Senckenberganlage 25, 60325, Frankfurt am Main, Germany.,Department of Biology, University of Padua, Via U. Bassi 58/B, Padua, Italy
| | - Jürgen Otte
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325, Frankfurt am Main, Germany
| | - Garima Singh
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325, Frankfurt am Main, Germany.,LOEWE Center for Translational Biodiversity Genomics (TBG), Senckenberganlage 25, 60325, Frankfurt am Main, Germany.,Department of Biology, University of Padua, Via U. Bassi 58/B, Padua, Italy
| | - Dominik Merges
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325, Frankfurt am Main, Germany.,LOEWE Center for Translational Biodiversity Genomics (TBG), Senckenberganlage 25, 60325, Frankfurt am Main, Germany.,Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, P.O. Box 7070, 750 07, Uppsala, Sweden
| | - Imke Schmitt
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325, Frankfurt am Main, Germany. .,LOEWE Center for Translational Biodiversity Genomics (TBG), Senckenberganlage 25, 60325, Frankfurt am Main, Germany. .,Department of Biological Sciences, Institute of Ecology, Evolution and Diversity, Goethe University Frankfurt, Max-von-Laue-Straße 13, 60438, Frankfurt am Main, Germany.
| |
Collapse
|
5
|
The long-term effect of removing the UV-protectant usnic acid from the thalli of the lichen Cladonia foliacea. Mycol Prog 2022; 21:83. [PMID: 36065212 PMCID: PMC9433529 DOI: 10.1007/s11557-022-01831-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 07/31/2022] [Accepted: 08/04/2022] [Indexed: 10/25/2022]
Abstract
AbstractTerricolous lichens are abundant in semi-arid areas, where they are exposed to high irradiation. Photoprotection is essential for the algae as the photobiont provides the primer carbon source for both symbionts. The UV-protectant lichen metabolites and different quenching procedures of the alga ensure adequate photoprotection. Since the long-term effect of diminishing UV-protectant lichen metabolites is unknown, a major part of lichen secondary metabolites was removed from Cladonia foliacea thalli by acetone rinsing, and the lichens were then maintained under field conditions to investigate the effect on both symbionts for 3 years. Our aim was to determine if the decreased level of UV-protectant metabolites caused an elevated photoprotection in the algae and to reveal the dynamics of production of the metabolites. Photosynthetic activity and light protection were checked by chlorophyll a fluorescence kinetics measurements every 6 months. The concentrations of fumarprotocetraric and usnic acids were monitored by chromatographic methods. Our results proved that seasonality had a more pronounced effect than that of acetone treatment on the function of lichens over a long-term scale. Even after 3 years, the acetone-treated thalli contained half as much usnic acid as the control thalli, and the level of photoprotection remained unchanged in the algae. However, the amount of available humidity was a more critical limiting environmental factor than the amount of incoming irradiation affecting usnic acid production. The lichenicolous fungus Didymocyrtis cladoniicola became relatively more abundant in the acetone-treated samples than in the control samples, indicating a slight change caused by the treatment.
Collapse
|
6
|
Photoprotection and high-light acclimation in semi-arid grassland lichens – a cooperation between algal and fungal partners. Symbiosis 2021. [DOI: 10.1007/s13199-021-00823-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
AbstractIn lichens, each symbiotic partner cooperates for the survival of the symbiotic association. The protection of the susceptible photosynthetic apparatus is essential for both participants. The mycobiont and photobiont contribute to the protection against the damaging effect of excess light by various mechanisms. The present study investigated the effect of seasonality and microhabitat exposure on photoprotection and photoacclimation in the photo- and the mycobiont of six lichen species with different thallus morphology in inland dune system in the Kiskunság region (Hungary) with shaded, more humid and exposed, drier dune sides. High-Performance Liquid Chromatography, spectrophotometry, chlorophyll a fluorescence kinetic technique were used, and micrometeorological data were collected. The four years data series revealed that the north-east-facing side was characterized by higher relative humidity and lower light intensities compared to the south-west-facing drier and more exposed sides. The south-west facing side was exposed to direct illumination 3–4 hours longer in winter and 1–2 hours shorter in summer than the north-east facing side of the dune, influencing the metabolism of sun and shade populations of various species. Because rapid desiccation caused short active periods of lichens during bright and drier seasons and on exposed microhabitats, the rapid, non-regulated non-photochemical quenching mechanisms in the photobiont had a significant role in protecting the photosynthetic system in the hydrated state. In dehydrated conditions, thalli were mainly defended by the solar screening metabolites produced by the mycobiont and curling during desiccation (also caused by the mycobiont). Furthermore, the efficacy of light use (higher chlorophyll and carotenoid concentration) increased because of short hydrated periods. Still, a lower level of received irradiation was appropriate for photosynthesis in dry seasons and on sun exposed habitats. In humid seasons and microhabitats, more extended active periods lead to increased photosynthesis and production of solar radiation protectant fungal metabolites, allowing a lower level of photoprotection in the form of regulated non-photochemical quenching by the photobiont. Interspecific differences were more pronounced than the intraspecific ones among seasons and microhabitat types.
Collapse
|
7
|
Ivanov D, Yaneva G, Potoroko I, Ivanova DG. Contribution of Cyanotoxins to the Ecotoxicological Role of Lichens. Toxins (Basel) 2021; 13:321. [PMID: 33946807 PMCID: PMC8146415 DOI: 10.3390/toxins13050321] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/22/2021] [Accepted: 04/27/2021] [Indexed: 12/02/2022] Open
Abstract
The fascinating world of lichens draws the attention of the researchers because of the numerous properties of lichens used traditionally and, in modern times, as a raw material for medicines and in the perfumery industry, for food and spices, for fodder, as dyes, and for other various purposes all over the world. However, lichens being widespread symbiotic entities between fungi and photosynthetic partners may acquire toxic features due to either the fungi, algae, or cyano-procaryotes producing toxins. By this way, several common lichens acquire toxic features. In this survey, recent data about the ecology, phytogenetics, and biology of some lichens with respect to the associated toxin-producing cyanoprokaryotes in different habitats around the world are discussed. Special attention is paid to the common toxins, called microcystin and nodularin, produced mainly by the Nostoc species. The effective application of a series of modern research methods to approach the issue of lichen toxicity as contributed by the cyanophotobiont partner is emphasized.
Collapse
Affiliation(s)
- Dobri Ivanov
- Department of Biochemistry, Molecular Medicine and Nutrigenomics, Faculty of Pharmacy, Medical University “Prof. Dr. Paraskev Stoyanov”, 9002 Varna, Bulgaria; (G.Y.); (D.G.I.)
| | - Galina Yaneva
- Department of Biochemistry, Molecular Medicine and Nutrigenomics, Faculty of Pharmacy, Medical University “Prof. Dr. Paraskev Stoyanov”, 9002 Varna, Bulgaria; (G.Y.); (D.G.I.)
| | - Irina Potoroko
- Department of Food and Biotechnologies, School of Medical Biology, South Ural State University, 454080 Chelyabinsk, Russia;
| | - Diana G. Ivanova
- Department of Biochemistry, Molecular Medicine and Nutrigenomics, Faculty of Pharmacy, Medical University “Prof. Dr. Paraskev Stoyanov”, 9002 Varna, Bulgaria; (G.Y.); (D.G.I.)
| |
Collapse
|
8
|
The bright and shaded side of duneland life: the photosynthetic response of lichens to seasonal changes is species-specific. Mycol Prog 2020. [DOI: 10.1007/s11557-020-01584-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
AbstractTerricolous lichens are relevant associates of biological soil crusts in arid and semiarid environments. Dunes are ecosystems of high conservation interest, because of their unique, vulnerable and threatened features. The function of lichens is affected by the changing seasons and different microhabitat conditions. At the same time, inland dunes are less investigated areas from the terricolous lichens point of view. We explored the effect of seasonal variation and different micro-environmental conditions (aspect) on the metabolic activity of five terricolous lichen species, representing various growth forms, in temperate semiarid grasslands. Populations of Cladonia foliacea, C. furcata, C. pyxidata group, Diploschistes muscorum and Thalloidima physaroides were investigated. Thalli sampled from the south-west and north-east facing microhabitats were studied by chlorophyll fluorescence analysis for 2 years. The present study aims to understand how changing climate (during the year) and aspect affect photosynthetic activity and photoprotection. Microclimatic data were also continuously recorded to reveal the background of the difference between microhabitat types. As a result, the air temperature, photosynthetically active radiation, soil temperature and vapour pressure deficit were significantly higher on south-west than on north-east facing microsites, where relative humidity and water content of soil proved to be considerably higher. Higher photosynthetic activity, as well as a higher level of photoprotection, was detected in lichens from north-east-oriented microsites compared with south-west populations. In addition, the difference between sun and shade populations varied seasonally. Since a species-specific response to both aspect and season was detected, we propose to investigate more than one species of different growth forms, to reveal the response of lichens to the changing environment in space and time.
Collapse
|
9
|
Can Parietin Transfer Energy Radiatively to Photosynthetic Pigments? Molecules 2018; 23:molecules23071741. [PMID: 30018202 PMCID: PMC6099737 DOI: 10.3390/molecules23071741] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 07/12/2018] [Accepted: 07/16/2018] [Indexed: 12/04/2022] Open
Abstract
The main role of lichen anthraquinones is in protection against biotic and abiotic stresses, such as UV radiation. These compounds are frequently deposited as crystals outside the fungal hyphae and most of them emit visible fluorescence when excited by UV. We wondered whether the conversion of UV into visible fluorescence might be photosynthetically used by the photobiont, thereby converting UV into useful energy. To address this question, thalli of Xanthoria parietina were used as a model system. In this species the anthraquinone parietin accumulates in the outer upper cortex, conferring the species its characteristic yellow-orange colouration. In ethanol, parietin absorbed strongly in the blue and UV-B and emitted fluorescence in the range 480–540 nm, which partially matches with the absorption spectra of photosynthetic pigments. In intact thalli, it was determined by confocal microscopy that fluorescence emission spectra shifted 90 nm towards longer wavelengths. Then, to study energy transfer from parietin, we compared the response to UV of untreated and parietin-free thalli (removed with acetone). A chlorophyll fluorescence kinetic assessment provided evidence of UV-induced electron transport, though independently of the presence of parietin. Thus, a role for anthraquinones in energy harvesting is not supported for X. parietina under presented experimental conditions.
Collapse
|
10
|
Petruzzellis F, Savi T, Bertuzzi S, Montagner A, Tretiach M, Nardini A. Relationships between water status and photosystem functionality in a chlorolichen and its isolated photobiont. PLANTA 2018; 247:705-714. [PMID: 29170912 DOI: 10.1007/s00425-017-2814-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 11/14/2017] [Indexed: 05/15/2023]
Abstract
Drought tolerance was greater in the whole lichen than in its isolated photobiont. Cell turgor state has an influence on the functionality of photosynthetic process in lichens. Irreversible thermodynamics is widely used to describe the water relations of vascular plants. However, poikilohydrous organisms like lichens and aeroterrestrial microalgae have seldom been studied using this approach. Water relations of lichens are generally addressed without separate analysis of the mycobiont and photobiont, and only few studies have correlated changes in photosynthetic efficiency of dehydrating lichens to accurate measurements of their water potential components. We measured water potential isotherms and chlorophyll a fluorescence in the lichen Flavoparmelia caperata harvested in different seasons, as well as in its isolated photobiont, the green alga Trebouxia gelatinosa, either exposed to water stress cycles or fully hydrated. No significant seasonal trends were observed in lichen water relations parameters. Turgor loss point and osmotic potential of the whole thallus were significantly lower than those measured in the photobiont, while differences between the water stressed photobiont and controls were not significant. Dehydration-induced drop of F v/F m was correlated with turgor loss, revealing that the photosynthetic activity of lichens partly depends on their turgor level. We provided one of the first quantitative evidences of the influence that turgor status could exert on the functionality of photosynthetic processes in lichens.
Collapse
Affiliation(s)
- Francesco Petruzzellis
- Department of Life Sciences, University of Trieste, Via L. Giorgieri 10, 34127, Trieste, Italy.
| | - Tadeja Savi
- Department of Life Sciences, University of Trieste, Via L. Giorgieri 10, 34127, Trieste, Italy
| | - Stefano Bertuzzi
- Department of Life Sciences, University of Trieste, Via L. Giorgieri 10, 34127, Trieste, Italy
| | - Alice Montagner
- Department of Life Sciences, University of Trieste, Via L. Giorgieri 10, 34127, Trieste, Italy
| | - Mauro Tretiach
- Department of Life Sciences, University of Trieste, Via L. Giorgieri 10, 34127, Trieste, Italy
| | - Andrea Nardini
- Department of Life Sciences, University of Trieste, Via L. Giorgieri 10, 34127, Trieste, Italy
| |
Collapse
|
11
|
Kosanić M, Ranković B, Stanojković T, Rančić A, Manojlović N. Cladonia lichens and their major metabolites as possible natural antioxidant, antimicrobial and anticancer agents. Lebensm Wiss Technol 2014. [DOI: 10.1016/j.lwt.2014.04.047] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
12
|
Grujičić D, Stošić I, Kosanić M, Stanojković T, Ranković B, Milošević-Djordjević O. Evaluation of in vitro antioxidant, antimicrobial, genotoxic and anticancer activities of lichen Cetraria islandica. Cytotechnology 2014; 66:803-13. [PMID: 24590925 DOI: 10.1007/s10616-013-9629-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 08/04/2013] [Indexed: 10/25/2022] Open
Abstract
In this study, the antioxidant, antimicrobial, genotoxic and anticancer activities of Cetraria islandica methanol extract were determined by using free radical and superoxide anion scavenging activity, reducing power, determination of total phenolic compounds and flavonoid contents, broth microdilution minimal inhibitory concentration against five bacterial and five fungal species, cytokinesis block micronucleus (MN) assay on peripheral blood lymphocytes (PBLs) and the microculture tetrazolium test on FemX (human melanoma) and LS174 (human colon carcinoma) cell lines. As a result of the study, we found that C. islandica methanol extract exhibited moderate free-radical-scavenging activity with IC50 values 678.38 μg/ml. Moreover, the tested extract had effective reducing power and superoxide anion radical scavenging. The minimal inhibitory concentration values against the tested microorganisms ranged from 0.312 to 5 mg/ml. The extract increased MN frequency in a dose dependent manner, but it was significant in higher tested concentrations (50, 100 and 200 μg/ml). No significant differences were observed between NDI values in all treatments and untreated PBLs. In addition, the tested extract had strong anticancer activity towards both cell lines with IC50 values of 22.68 and 33.74 μg/ml. It can be concluded that the tested extract exhibited a certain level of in vitro antioxidant, antimicrobial, genotoxic and anticancer activities.
Collapse
Affiliation(s)
- Darko Grujičić
- Faculty of Science, University of Kragujevac, 34000, Kragujevac, Serbia
| | | | | | | | | | | |
Collapse
|
13
|
Gauslaa Y, Bidussi M, Solhaug KA, Asplund J, Larsson P. Seasonal and spatial variation in carbon based secondary compounds in green algal and cyanobacterial members of the epiphytic lichen genus Lobaria. PHYTOCHEMISTRY 2013; 94:91-98. [PMID: 23664176 DOI: 10.1016/j.phytochem.2013.04.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 04/02/2013] [Accepted: 04/06/2013] [Indexed: 06/02/2023]
Abstract
Acetone-extractable carbon based secondary compounds (CBSCs) were quantified in two epiphytic lichens to study possible effects of external factors (season and aspect) on secondary chemistry and to relate defense investments to biomass growth and changes in specific thallus mass (STM). At the end of four separate annual cycles starting in each of the four seasons, the cyanolichen Lobaria scrobiculata and the cephalolichen Lobaria pulmonaria (green algae as the primary photobiont and with localized Nostoc in internal cephalodia) were monitored in their natural forest habitats and after being transplanted at three contrasting aspects in open sites. Season strongly influenced most CBSCs. Medullary CBSCs in both species were twice as high in summer as in winter. Aspect hardly affected major CBSCs, whereas transplantation from forest to clear-cut slightly reduced these compounds. No major CBSCs in any species showed a trade-off with growth rate. Dry matter- as well as thallus area-based medullary CBSC contents increased with STM. The cortical usnic acid strongly increased with growth rate and followed spatial, but not seasonal variations in light exposure. Maximal CBSC levels during seasons with most herbivores is consistent with the hypothesis inferring that herbivory is a major selective force for CBSCs. Lack of trade-off between growth and defence investments suggests that these two processes do not compete for photosynthates.
Collapse
Affiliation(s)
- Yngvar Gauslaa
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, N-1432 Ås, Norway.
| | | | | | | | | |
Collapse
|
14
|
Domaschke S, Vivas M, Sancho LG, Printzen C. Ecophysiology and genetic structure of polar versus temperate populations of the lichen Cetraria aculeata. Oecologia 2013; 173:699-709. [PMID: 23649754 DOI: 10.1007/s00442-013-2670-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Accepted: 04/17/2013] [Indexed: 02/07/2023]
Abstract
We studied polar and temperate samples of the lichen Cetraria aculeata to investigate whether genetical differences between photobionts are correlated with physiological properties of the lichen holobiont. Net photosynthesis and dark respiration (DR) at different temperatures (from 0 to 30 °C) and photon flux densities (from 0 to 1,200 μmol m(-2) s(-1)) were studied for four populations of Cetraria aculeata. Samples were collected from maritime Antarctica, Svalbard, Germany and Spain, representing different climatic situations. Sequencing of the photobiont showed that the investigated samples fall in the polar and temperate clade described in Fernández-Mendoza et al. (Mol Ecol 20:1208-1232, 2011). Lichens with photobionts from these clades differ in their temperature optimum for photosynthesis, maximal net photosynthesis, maximal DR and chlorophyll content. Maximal net photosynthesis was much lower in Antarctica and Svalbard than in Germany and Spain. The difference was smaller when rates were expressed by chlorophyll content. The same is true for the temperature optima of polar (11 °C) and temperate (15 and 17 °C) lichens. Our results indicate that lichen mycobionts may adapt or acclimate to local environmental conditions either by selecting algae from regional pools or by regulating algal cell numbers (chlorophyll content) within the thallus.
Collapse
Affiliation(s)
- S Domaschke
- Department of Botany and Molecular Evolution, Senckenberg Research Institute, Senckenberganlage 25, 60325, Frankfurt am Main, Germany,
| | | | | | | |
Collapse
|
15
|
Seasonal acclimation in the epiphytic lichen Parmelia sulcata is influenced by change in photobiont population density. Oecologia 2013; 173:649-63. [DOI: 10.1007/s00442-013-2654-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Accepted: 04/03/2013] [Indexed: 10/26/2022]
|
16
|
Nguyen KH, Chollet-Krugler M, Gouault N, Tomasi S. UV-protectant metabolites from lichens and their symbiotic partners. Nat Prod Rep 2013; 30:1490-508. [DOI: 10.1039/c3np70064j] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
17
|
Kosanić M, Manojlović N, Janković S, Stanojković T, Ranković B. Evernia prunastri and Pseudoevernia furfuraceae lichens and their major metabolites as antioxidant, antimicrobial and anticancer agents. Food Chem Toxicol 2012; 53:112-8. [PMID: 23220145 DOI: 10.1016/j.fct.2012.11.034] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 11/21/2012] [Accepted: 11/22/2012] [Indexed: 11/29/2022]
Abstract
The aim of this study is to investigate chemical composition of acetone extracts of the lichens Evernia prunastri and Pseudoevernia furfuraceae and in vitro antioxidant, antimicrobial, and anticancer activities of these extracts and some their major metabolites. HPLC-UV method was used for identification of secondary metabolites. Antioxidant activity was evaluated by free radical scavenging, superoxide anion radical scavenging, reducing power and determination of total phenolic compounds. As a result of the study physodic acid had largest antioxidant activities. Total content of phenol in extracts was determined as pyrocatechol equivalent. The antimicrobial activity was estimated by determination of the minimal inhibitory concentration by the broth microdilution method. The most active was also physodic acid. Anticancer activity was tested against FemX (human melanoma) and LS174 (human colon carcinoma) cell lines using MTT method.
Collapse
Affiliation(s)
- Marijana Kosanić
- Department of Biology, Faculty of Science, University of Kragujevac, 34000 Kragujevac, Serbia
| | | | | | | | | |
Collapse
|
18
|
Biological activities of Toninia candida and Usnea barbata together with their norstictic acid and usnic acid constituents. Int J Mol Sci 2012. [PMID: 23203090 PMCID: PMC3509606 DOI: 10.3390/ijms131114707] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
The aim of this study was to investigate the chemical composition of acetone extracts of the lichens Toninia candida and Usnea barbata and in vitro antioxidant, antimicrobial, and anticancer activities of these extracts together with some of their major metabolites. The chemical composition of T. candida and U. barbata extracts was determined using HPLC-UV analysis. The major phenolic compounds in these extracts were norstictic acid (T. candida) and usnic acid (U. barbata). Antioxidant activity was evaluated by free radical scavenging, superoxide anion radical scavenging, reducing power and determination of total phenolic compounds. Results of the study proved that norstictic acid had the largest antioxidant activity. The total content of phenols in the extracts was determined as the pyrocatechol equivalent. The antimicrobial activity was estimated by determination of the minimal inhibitory concentration using the broth microdilution method. The most active was usnic acid with minimum inhibitory concentration values ranging from 0.0008 to 0.5 mg/mL. Anticancer activity was tested against FemX (human melanoma) and LS174 (human colon carcinoma) cell lines using the microculture tetrazolium test. Usnic acid was found to have the strongest anticancer activity towards both cell lines with IC(50) values of 12.72 and 15.66 μg/mL.
Collapse
|
19
|
Larsson P, Solhaug KA, Gauslaa Y. Seasonal partitioning of growth into biomass and area expansion in a cephalolichen and a cyanolichen of the old forest genus Lobaria. THE NEW PHYTOLOGIST 2012; 194:991-1000. [PMID: 22452484 DOI: 10.1111/j.1469-8137.2012.04130.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Growth in two old forest lichens was studied to evaluate how temporal (seasonal) and spatial (aspect-wise) partitioning of biomass and area growth respond to seasonal changes in light and climate. We monitored relative growth rates during annual courses in the cephalolichen Lobaria pulmonaria and the cyanolichen Lobaria scrobiculata transplanted in boreal clear-cut to five fixed aspects in winter, spring, summer, and autumn. For each annual set, growth was quantified in January-March, April-June, July-September and October-December. Mean biomass and area increased in all seasons, but growth was highest in July-September. Mass growth did not follow area increment during a year. As a result, mass per area (specific thallus mass (STM)) declined (L. scrobiculata) or stayed constant (L. pulmonaria) in the dark, humid October-December season, whereas it strongly increased in the dry, sunny April-June season. Aspect influenced growth in species-specific ways. Seasonality in biomass growth mainly followed light availability, whereas area growth was strongest during humid seasons. The substantial STM changes across seasons, species, and aspects can be explained as passive responses to seasonal climate. However, as STM, according to the literature, is a driver of water storage, recorded changes probably improve fitness by prolonging hydration in places or during times with high evaporative demands.
Collapse
Affiliation(s)
- Per Larsson
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003, N-1432 Ås, Norway
| | - Knut Asbjørn Solhaug
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003, N-1432 Ås, Norway
| | - Yngvar Gauslaa
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003, N-1432 Ås, Norway
| |
Collapse
|
20
|
Secondary Lichen Compounds as Protection Against Excess Solar Radiation and Herbivores. PROGRESS IN BOTANY 2012. [DOI: 10.1007/978-3-642-22746-2_11] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
|
21
|
Maphangwa KW, Musil CF, Raitt L, Zedda L. Experimental climate warming decreases photosynthetic efficiency of lichens in an arid South African ecosystem. Oecologia 2011; 169:257-68. [PMID: 22057927 DOI: 10.1007/s00442-011-2184-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Accepted: 10/20/2011] [Indexed: 11/24/2022]
Abstract
Elevated temperatures and diminished precipitation amounts accompanying climate warming in arid ecosystems are expected to have adverse effects on the photosynthesis of lichen species sensitive to elevated temperature and/or water limitation. This premise was tested by artificially elevating temperatures (increase 2.1-3.8°C) and reducing the amounts of fog and dew precipitation (decrease 30.1-31.9%), in an approximation of future climate warming scenarios, using transparent hexagonal open-top warming chambers placed around natural populations of four lichen species (Xanthoparmelia austroafricana, X. hyporhytida , Xanthoparmelia. sp., Xanthomaculina hottentotta) at a dry inland site and two lichen species (Teloschistes capensis and Ramalina sp.) at a humid coastal site in the arid South African Succulent Karoo Biome. Effective photosynthetic quantum yields ([Formula: see text]) were measured hourly throughout the day at monthly intervals in pre-hydrated lichens present in the open-top warming chambers and in controls which comprised demarcated plots of equivalent open-top warming chamber dimensions constructed from 5-cm-diameter mesh steel fencing. The cumulative effects of the elevated temperatures and diminished precipitation amounts in the open-top warming chambers resulted in significant decreases in lichen [Formula: see text]. The decreases were more pronounced in lichens from the dry inland site (decline 34.1-46.1%) than in those from the humid coastal site (decline 11.3-13.7%), most frequent and prominent in lichens at both sites during the dry summer season, and generally of greatest magnitude at or after the solar noon in all seasons. Based on these results, we conclude that climate warming interacting with reduced precipitation will negatively affect carbon balances in endemic lichens by increasing desiccation damage and reducing photosynthetic activity time, leading to increased incidences of mortality.
Collapse
|
22
|
Tretiach M, Pavanetto S, Pittao E, Sanità di Toppi L, Piccotto M. Water availability modifies tolerance to photo-oxidative pollutants in transplants of the lichen Flavoparmelia caperata. Oecologia 2011; 168:589-99. [DOI: 10.1007/s00442-011-2104-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Accepted: 08/02/2011] [Indexed: 10/17/2022]
|
23
|
Sensitivity of Xanthoria parietina to UV-A: Role of metabolic modulators. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2011; 103:243-50. [DOI: 10.1016/j.jphotobiol.2011.04.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 03/29/2011] [Accepted: 04/04/2011] [Indexed: 11/17/2022]
|
24
|
Influence of sun irradiance and water availability on lichen photosynthetic pigments during a Mediterranean summer. Biologia (Bratisl) 2010. [DOI: 10.2478/s11756-010-0087-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
25
|
Space Flight Effects on Lichen Ultrastructure and Physiology. CELLULAR ORIGIN, LIFE IN EXTREME HABITATS AND ASTROBIOLOGY 2010. [DOI: 10.1007/978-90-481-9449-0_30] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
26
|
Jairus K, Lõhmus A, Lõhmus P. Lichen acclimatization on retention trees: a conservation physiology lesson. J Appl Ecol 2009. [DOI: 10.1111/j.1365-2664.2009.01672.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
27
|
Kranner I, Beckett R, Hochman A, Nash TH. Desiccation-Tolerance in Lichens: A Review. THE BRYOLOGIST 2008; 111:576-593. [PMID: 0 DOI: 10.1639/0007-2745-111.4.576] [Citation(s) in RCA: 160] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
|
28
|
Gauslaa Y, Palmqvist K, Solhaug KA, Hilmo O, Holien H, Nybakken L, Ohlson M. Size-dependent growth of two old-growth associated macrolichen species. THE NEW PHYTOLOGIST 2008; 181:683-692. [PMID: 19032441 DOI: 10.1111/j.1469-8137.2008.02690.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Relationships between thallus size and growth variables were analysed for the foliose Lobaria pulmonaria and the pendulous Usnea longissima with the aim of elucidating their morphogenesis and the factors determining thallus area (A) versus biomass (dry weight (DW) gain. Size and growth data originated from a factorial transplantation experiment that included three boreal climate zones (Atlantic, suboceanic and continental), each with three successional forest stands (clear-cut, young and old). When A was replaced by the estimated photobiont layer area in an area-DW scatterplot including all thalli (n = 1080), the two separate species clusters merged into one, suggesting similar allocation patterns between photobionts and mycobionts across growth forms. During transplantation, stand-specific water availability boosted area gain in foliose transplants, consistent with a positive role of water in fungal expansion. In pendulous lichens, A gain greatly exceeded DW gain, particularly in small transplants. The A gain in U. longissima increased with increasing DW:A ratio, consistent with a reallocation of carbon, presumably mobilized from the dense central chord. Pendulous lichens with cylindrical photobiont layers harvest light from all sides. Rapid and flexible three-dimensional A gain allows the colonization of spaces between canopy branches to utilize temporary windows of light in a growing canopy. Foliose lichens with a two-dimensional photobiont layer have more coupled A and DW gains.
Collapse
Affiliation(s)
- Yngvar Gauslaa
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003, NO-1432 As, Norway.
| | | | | | | | | | | | | |
Collapse
|
29
|
McEvoy M, Gauslaa Y, Solhaug KA. Changes in pools of depsidones and melanins, and their function, during growth and acclimation under contrasting natural light in the lichen Lobaria pulmonaria. THE NEW PHYTOLOGIST 2007; 175:271-282. [PMID: 17587375 DOI: 10.1111/j.1469-8137.2007.02096.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
This study analysed relationships between secondary chemistry, lichen growth rates and external habitat factors for two groups of UV-B-absorbing secondary compounds in the lichen Lobaria pulmonaria in order to test some hypotheses on their formation and function. Medullary depsidones and cortical melanins were quantified in thalli transplanted to three successional forest stands (shaded young forest, open old forest, sun-exposed clear-cut area) and subjected to different watering regimes (spraying with water, water + nitrogen, no spraying). Growth rates were already known. The total concentration of all seven depsidones was constant across the entire range of growth rates and sun exposures, showing that these depsidones serve functions other than photoprotection. Thalli from the well-lit transplantation sites had the highest synthesis of melanins. Within each forest type there was a trade-off between growth and melanin synthesis. Melanins and photosynthetic acclimation enhanced survival on a subsequent exposure to high light intensity, despite excessive temperatures resulting from higher absorption of solar energy in melanic thalli relative to pale thalli. In conclusion, the highly responsive melanic pigments play a photoprotective role in light acclimation, whereas the constant amount of depsidones across a wide spectrum of growth ranges and irradiances is consistent with herbivore defence functions.
Collapse
Affiliation(s)
- Maria McEvoy
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003, N-1432 Ås, Norway
| | - Yngvar Gauslaa
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003, N-1432 Ås, Norway
| | - Knut Asbjørn Solhaug
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003, N-1432 Ås, Norway
| |
Collapse
|
30
|
Barták M, Solhaug KA, Vráblíková H, Gauslaa Y. Curling during desiccation protects the foliose lichen Lobaria pulmonaria against photoinhibition. Oecologia 2006; 149:553-60. [PMID: 16804701 DOI: 10.1007/s00442-006-0476-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2005] [Accepted: 05/26/2006] [Indexed: 10/24/2022]
Abstract
This study aims to assess the photoprotective potential of desiccation-induced curling in the light-susceptible old forest lichen Lobaria pulmonaria by using chlorophyll fluorescence imaging. Naturally curled thalli showed less photoinhibition-induced limitations in primary processes of photosynthesis than artificially flattened specimens during exposures to 450 micromol m-2 s-1 in the laboratory after both 12- (medium dose treatment) and 62-h duration (high dose treatment). Thallus areas shaded by curled lobes during light exposure showed unchanged values of measured chlorophyll fluorescence parameters (FV/FM, PhiPS II), whereas non-shaded parts of curled thalli, as well as the mean for the entire flattened thalli, showed photoinhibitory limitation after light treatments. Furthermore, the chlorophyll fluorescence imaging showed that the typical small-scale reticulated ridges on the upper side of L. pulmonaria caused a spatial, small-scale reduction in damage due to minor shading. Severe dry-state photoinhibition readily occurred in flattened and light-treated L. pulmonaria, although the mechanisms for such damage in a desiccated and inactive stage are not well known. Natural curling is one strategy to reduce the chance for serious photoinhibition in desiccated L. pulmonaria thalli during high light exposures.
Collapse
Affiliation(s)
- Milos Barták
- Department of Plant Physiology and Anatomy, Masaryk University, Kotlarska 2, 61137, Brno, Czech Republic
| | | | | | | |
Collapse
|