Thallus morphology of two Antarctic foliose lichens evaluated by a digital optical microscopy approach ( Short Communication)
Vol.6,No.1(2016)
Digital microscopy is an emerging technique that combines the tools of classic light microscopy with a computerized imaging system. The main components of digital microscopy is image formation by optics of the system, image registration by a digital camera, saving of image data in a file format that enables advanced image analysis.In this paper, we bring first data on application of digital microscopy approach in lichen thallus morphology study. Two Antarctic lichen species (Xanthoria elegans, Umbilicaria decussata) with a foliose morphotype of their thallus were studied. Both experimental species had an irregularly round or eliptic shape of a thallus that enabled to measure its diameter. After magnifition, images were taken in dry and fully-hydrated state of thallus in order to evaluate hydration-dependent size changes in thallus size and structures. It has been demonstrated that hydration-dependent size increment depend on thallus size and particular part of thallus. Mean increment of thallus diameter reached 15.1% and 13.8% for X. elegans and U. decussata, respectively. Higher value of diameter increment (26 %) was found for the upper projection area of apothecia, fruiting bodies developed over the upper thallus surface of X. elegans. Size and volume increment in thallus parts is discussed as a consequence of water holding capacity of lichens, and a capability of lichens to hold intra- and extracellular water upon full hydration of a thallus. Finally, a potential of digital microscopy for future studies is discussed as well as some processing techniques such as e.g. metrics of profile lines through 3-D objects like apothecia.
Xanthoria elegans; Umbilicaria decussata; thallus hydration; thallus dimension; morphometry
Barták, M., Gloser, J. and Hájek, J. (2005): Visualized photosynthetic characteristics of the lichen Xanthoria elegans related to daily courses of light, temperature and hydration: A field study from Galindez Island, maritime Antarctica. The Lichenologist, 37: 433-443
Barták, M., Solhaug, K. A., Vráblíková, H. and Gauslaa, Y. (2006): Curling during desiccation protects the foliose lichen Lobaria pulmonaria against photoinhibition. Oecologia, 149: 553-60.
Dahlman, L., Palmqvist, K. (2003): Growth in two foliose tripartite lichens, Nephroma arcticum and Peltigera aphthosa. Functional Ecology, 17:821-831.
De los Ríos, A., Ascaso, C. and Wierzchos, J. (1999): Study of lichens with different state of hydration by the combination of low temperature scanning electron and confocal laser scanning microscopies. International Microbiology, 2: 251-257.
Esseen, P. A., Olsson, T., Coxton, D. and Gauslaa, Y. (2015): Morphology influences water storage in hair lichens from boreal forest canopies. Fungal ecology, 18: 26-35.
Fos, S., Deltoro, V. I., Calatayud, A. and Barreno, E. (1999): Changes in Water Economy in Relation to Anatomical and Morphological Characteristics During Thallus Development in Parmelia acetabulum. The Lichenologist, 31: 375-387.
Gauslaa, Y., Coxson, D. (2011): Interspecific and intraspecific variations in water storage in epiphytic old forest foliose lichens. Botany, 89: 787-798.
Gauslaa, Y., Solhaug, K.-A. (1998): The significance of thallus size for the water economy of the cyanobacterial old-forest lichen Degelia plumbea. Oecologia, 116: 76-84.
Jupa, R., Hájek, J., Hazdrová, J. and Barták, M. (2012): Interspecific differences in photosynthetic efficiency and spectral reflectance in two Umbilicaria species from Svalbard during controlled desiccation. Czech Polar Reports, 2: 31-41.
Kappen, L., Valladares, F. (1999): Opportunistic growth and desiccation tolerance: the ecological success of poikilohydrous autotrophs. In: F. I. Pugnaire, F. Valladares (eds.): Handbook of functional plant ecology. New York: Marcel Dekker, Inc, pp. 10-80.
Lange, O. L., Green, T. G. A., Reichenberger, H. and Meyer, A. (1996): Photosynthetic depression at high thallus water content in lichens: concurrent use of gas exchange and fluorescence techniques with a cyanobacterial and a green algal Peltigera species. Botanica Acta, 109: 43-50.
Lange, O. L., Green, T. G. A. and Heber, U. (2001): Hydration-dependent photosynthetic production of lichens: what do laboratory studies tell us about field performance? Journal of Experimental Botany, 52: 2033-2042.
Merinero, S., Hilmo, O. and Gauslaa, Y. (2014): Size is a main driver for hydration traits in cyano- and cephalolichens of boreal rainforest canopies. Fungal Ecology, 7: 59-66.
Nash, T. H., Ryan, B. D., Gries, C. and Bungartz, F. (eds.) (2004): Lichen flora of the Greater Sonoran Desert Region. Vol. 2., 742 p.
Olsson, T. (2014): Morphological traits in hair lichens affect their water storage. Thesis. University of Ume, Sweden. 26 p.
Scheidegger, C. (1994): Low temperature scanning electron microscopy: the localization of free and perturbed water and its role in the morphology of the lichen symbionts. Cryptogamic Botany, 4: 290-299.
Scheidegger, C., Schroeter, B. and Frey, B. (1995): Structural and functional processes during water vapour uptake and desiccation in selected lichens with green algal photobionts. Planta, 197: 399-409.
Snelgar, W. P., Green, T. G. A. (1981): Ecologically-linked variation in morphology, acetylene reduction, and water relations in Pseudocyphellaria dissimilis. New Phytologist, 87: 403-411.
Souza-Egipsy, V., Valladares, F. and Ascaso, C. (2000): Water Distribution in Foliose Lichen Species: Interactions between Method of Hydration, Lichen Substances and Thallus Anatomy. Annals of Botany, 86: 595-601.
Valladares, F., Sancho, L. G. and Ascaso, C. (1998): Water storage in the Lichen family Umbilicariaceae. Botanica Acta, 11: 1-9.,
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Copyright © 2020 Czech Polar Reports