Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-17T21:16:15.377Z Has data issue: false hasContentIssue false
  • English
  • Français

The gastropod Arion fuscus prefers cyanobacterial to green algal parts of the tripartite lichen Nephroma arcticum due to low chemical defence

Published online by Cambridge University Press:  26 November 2009

Johan ASPLUND  and
Yngvar GAUSLAA
Johan ASPLUND
Affiliation:
Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway. Email: johan.asplund@umb.no
Yngvar GAUSLAA
Affiliation:
Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås, Norway. Email: johan.asplund@umb.no
Get access Rights & Permissions [Opens in a new window]

Abstract

Although the tripartite terricolous lichen Nephroma arcticum is easily accessible to lichen-feeding gastropods, grazing marks are mainly restricted to localized cephalodia with N-fixing Nostoc. We tested if this gastropod preference for cephalodia can be explained by differences in carbon based secondary compounds (CBSCs) in cyanobacterial versus green-algal tissues. CBSCs were non-destructively removed from air-dry thalli by 100% acetone. Compound deficient and control thallus parts were offered to the slug Arion fuscus and grazing preferences were quantified by area measurements in ArcGIS™. The concentrations of CBSCs (phenarctin, usnic acid, nephroarctin and methyl gyrophorate) in thallus parts with and without cephalodia were quantified with HPLC. Compared to purely green-algal parts, cephalodial parts with adjoining fungal tissues contained less defensive compounds, and were preferred by A. fuscus. The cephalodia themselves do not contain any CBSCs. After acetone rinsing, A. fuscus did not discriminate between green-algal and cyanobacterial parts. The results were consistent with the hypothesis that CBSCs in green-algal parts of N. arcticum play a herbivore-defensive role. It is further hypothesized that grazing of cephalodia may lead to N-starvation and reduced growth of N. arcticum thalli in southern portions of its range where lichenivorous gastropods are more abundant. This may play a role in shaping the southern distribution limit of this arctic-boreal lichen species.

Keywords

acetone rinsingcephalodiumdepsidesherbivorymolluscs
Type
Research Article
Information
The Lichenologist , Volume 42 , Issue 1 , January 2010 , pp. 113 - 117
Copyright
Copyright © British Lichen Society 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Baur, A., Baur, B. & Fröberg, L. (1992) The effect of lichen diet on growth rate in the rock-dwelling land snails Chondrina dienta (Westerlund) and Balea perversa (Linnaeus). Journal of Molluscan Studies 58: 345–347.CrossRefGoogle Scholar
Baur, A., Baur, B. & Fröberg, L. (1994) Herbivory on calcicolous lichens: different food preferences and growth rates in two co-existing land snails. Oecologia 98: 313–319.CrossRefGoogle ScholarPubMed
Brodo, I. M., Sharnoff, S. D. & Sharnoff, S. (2001) Lichens of North America. New Haven: Yale University Press.Google Scholar
Dahlman, L., Näsholm, T. & Palmqvist, K. (2002) Growth, nitrogen uptake, and resource allocation in the two tripartite lichens Nephroma arcticum and Peltigera aphthosa during nitrogen stress. New Phytologist 153: 307–315.CrossRefGoogle Scholar
Fröberg, L., Baur, A. & Baur, B. (1993) Differential herbivore damage to calcicolous lichens by snails. Lichenologist 25: 83–95.CrossRefGoogle Scholar
Gauslaa, Y. (2005) Lichen palatability depends on investments in herbivore defence. Oecologia 143: 94–105.CrossRefGoogle ScholarPubMed
Hanley, M. E., Bulling, M. T. & Fenner, M. (2003) Quantifying individual feeding variability: implications for mollusc feeding experiments. Functional Ecology 17: 673–679.CrossRefGoogle Scholar
Hasselrot, T. E. (1953) Nordliga lavar i Syd- och Mellansverige. Acta Phytogeographica Suecica 33: 1–200.Google Scholar
James, P. W. & Henssen, A. (1976) The morphological and taxonomic significance of cephalodia. In Lichenology: Progress and Problems (Brown, D. H., Hawksworth, D. L. & Bailey, R. H. eds): 27–77. London: Academic Press.Google Scholar
Kerney, M. P. & Cameron, R. A. D. (1979) Land Snails of Britain and North-West Europe. London: Collins.Google Scholar
Lockwood, J. R. (1998) On the statistical analysis of multiple-choice feeding preference experiments. Oecologia 116: 475–481.CrossRefGoogle Scholar
McEvoy, M., Solhaug, K. A. & Gauslaa, Y. (2007) Solar radiation screening in usnic acid-containing cortices of the lichen Nephroma arcticum. Symbiosis 43: 143–150.Google Scholar
Peake, J. F. & James, P. W. (1967) Lichens and Mollusca. Lichenologist 3: 425–428.CrossRefGoogle Scholar
Poelt, J. (1969) Bestimmungsschlüssel europäischer Flechten. Lehre: Cramer.Google Scholar
Pöykkö, H., Hyvärinen, M. & Backor, M. (2005) Removal of lichen secondary metabolites affects food choice and survival of lichenivorous moth larvae. Ecology 86: 2623–2632.CrossRefGoogle Scholar
Renner, B. (1980) Untersuchungen zum Einfluss der symbiotischen Alge auf den Stoffwechsel und die Struktur des Flechtenlagers. Ph.D. thesis, University of Marburg.Google Scholar
Renner, B. (1982) The presence or absence of secondary metabolites in cephalodia and their possible implications. Journal of the Hattori Botanical Laboratory 52: 367–377.Google Scholar
Reutimann, P. & Scheidegger, C. (1987) Importance of lichen secondary products in food choice of two oribatid mites (Acari) in an alpine meadow ecosystem. Journal of Chemical Ecology 13: 363–369.CrossRefGoogle Scholar
Solhaug, K. A. & Gauslaa, Y. (1996) Parietin, a photoprotective secondary product of the lichen Xanthoria parietina. Oecologia 108: 412–418.CrossRefGoogle ScholarPubMed
Solhaug, K. A. & Gauslaa, Y. (2001) Acetone rinsing – a method for testing ecological and physiological roles of secondary compounds in living lichens. Symbiosis 30: 301–315.Google Scholar
Sundberg, B., Näsholm, T. & Palmqvist, K. (2001) The effect of nitrogen on growth and key thallus components in the two tripartite lichens, Nephroma arcticum and Peltigera aphthosa. Plant, Cell and Environment 24: 517–527.CrossRefGoogle Scholar
Tønsberg, T. & Holtan-Hartwig, J. (1983) Phycotype pairs in Nephroma, Peltigera and Lobaria in Norway. Nordic Journal of Botany 3: 681–688.CrossRefGoogle Scholar
Vitikainen, O. (2007) Nephromataceae. Nordic Lichen Flora 3:91–95.Google Scholar