EurekaMag.com logo
+ Site Statistics
References:
53,517,315
Abstracts:
29,339,501
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

Water distribution in foliose lichen species: interactions between method of hydration, lichen substances and thallus anatomy



Water distribution in foliose lichen species: interactions between method of hydration, lichen substances and thallus anatomy



Annals of Botany 86(3): 595-601



Three lichens (Neofuscelia pokornyi, N. pulla and Xanthoria parietina) from a semi-arid habitat were examined using low-temperature scanning electron microscopy to evaluate the effects of hydration method, lichen substances and thallus anatomy on the water distribution of hydrated thalli. In the Neofuscelia species, extracellular water within the thallus was observed in association with cracks in its otherwise impervious upper cortex, while X. parietina showed abundant extracellular water between medullary hyphae. Spraying the thalli followed by maintenance for 14-20h in a water-saturated atmosphere led to the disappearance of the external water film in X. parietina but not in the Neofuscelia species. Surface water was abundant in specimens of all species immediately after spraying for 15min. No extracellular water was observed inside the thallus 14-20h after spraying, but after rinsing with acetone its presence was detected in all three species. Hydric strategy correlated with cortex hygroscopicity: X. parietina, an aero-hygrophytic species, had a more hygroscopic upper cortex than the Neofuscelia species, which are substrate-hygrophytic. The hygroscopicity of the upper cortex was linked with the amount of extracellular water in the thalline interior. Differences between X. parietina and Neofuscelia in the polarity and distribution of their lichen substances agreed with species differences in the presence and distribution of free water both as a film over the surface and inside the thallus. Lichen substances appear to play a role in the maintenance of air-filled intrathalline spaces in species whose anatomy, habitat, or both, favour water-logged conditions. Copyright 2000 Annals of Botany Company.

Accession: 003611873

Download citation: RISBibTeXText

DOI: 10.1006/anbo.2000.1224

Download PDF Full Text: Water distribution in foliose lichen species: interactions between method of hydration, lichen substances and thallus anatomy



Related references

Freezing of water bound in lichen thallus as observed by 1H NMR. II. Freezing protection mechanisms in a cosmopolitan lichen Cladonia mitis and in Antarctic lichen species at different hydration levels. Colloids and Surfaces B: Biointerfaces 28(4): 251-260, 2003

A species of Chaetopeltidaceae in the thallus of a foliose lichen. Kryptogam Forsch Bayer Bot Ges Erforsch Heim Flora 7: 493-497, 1926

Ecological trends in lichen photosynthesis Data for 42 fruticose and foliose lichen species. Oecologia 3(3): 330-335, 1982

Accumulation of trace elements in the peripheral and central parts of a foliose lichen thallus. Bryologist 100(2): 251-253, 1997

Determination of the distribution of lichen substances in the thallus by fluorescence microscopy. Annales Botanici Fennici 27(2): 189-202, 1990

Competitive interactions between four foliose lichen species with and without nutrient enrichment. Symbiosis 28(4): 323-335, 2000

Content of secondary compounds depends on thallus size in the foliose lichen Lobaria pulmonaria. Lichenologist (London) 39(Part 3): 273-278, 2007

Do secondary substances in the thallus of a lichen promote CO 2 diffusion and prevent depression of net photosynthesis at high water content?. Oecologia 112(1): 1-3, 1997

Do secondary substances in the thallus of a lichen promote CO-2 diffusion and prevent depression of net photosynthesis at high water content?. Oecologia (berlin). 112(1): 1-3, 1997

Do Secondary Substances in the Thallus of a Lichen Promote CO Diffusion and Prevent Depression of Net Photosynthesis at High Water Content?. Oecologia 112(1): 1-3, 1997

Distribution pattern of 2 lichen substances evernic acid and obtusatic acid in the thallus of ramalina. Journal of Japanese Botany 59(4): 111-115, 1984

Freezing of water bound in lichen thallus as observed by 1H-NMR. I. Freezing of loosely bound water in Cladonia mitis at different hydration levels. Colloids and Surfaces B: Biointerfaces 28(4): 239-249, 2003

Influence of hydration state of the thallus on storage bodies of th e lichen phycobiont Myrmecia. Anales de edafologia y agrobiologia 45(1-2): 239-248, 1986

Lichen substances and systematics of the lobate species of the lichen genus Lecanora in the Holarctic. Oesterr Bot Z 112(3): 285-294, 1965

Cell aggregates derived from natural lichen thallus fragments antioxidant activities of lichen metabolites developed in vitro. Natural Product Communications: 11, -1918, 2008