Myco‐photobiontal selection in a Mediterranean cryptogam community with Fulgensia fulgida

Abstract

Summary• To examine the mode of dispersal and photobiont selectivity of Fulgensia fulgida we investigated the photobionts associated with the lichens of a community related to the Toninio-Psoretum decipientis association.• Photobionts and mycobionts were analysed using morphological (light microscopy) and molecular (internal transcribed spacer (ITS) and partial large subunit (LSU) nuclear ribosomal DNA sequencing) techniques.• The thalli of the mycobiont of F. fulgida , which were identical in their ITS and partial LSU-sequence, contained two strains of Trebouxia asymmetrica , one of them also present in a thallus of Toninia sedifolia . Other co-occurring lichens, namely Squamarina lentigera , Catapyrenium michelii and Collema cristatum , were shown to have Asterochloris irregularis , Myrmecia and Nostoc as photobionts.• It is suggested that F. fulgida is selective in its photobiont choice, that dispersal of the lichen has occurred by way of ascospores and subsequent independent relichenization events and that F. fulgida and T. sedifolia share the same photobiont pool. The results also suggest possible mechanisms of relichenization and strategies for future research on the selectivity of lichen bionts.

Fungal-algal interactions inRamalina menziesiiand its associated epiphytic lichen community

“…In lichens, one of the 'textbook examples' of symbiosis, the local composition of symbiotic partnerships between lichen-forming fungi and their photobionts is a fascinating issue (Beck et al , 2002Yahr et al 2004;Ohmura et al 2006). Progress has been made in recent years due to the development of molecular techniques that allow a straightforward identification of photobiont and fungal genetic strains and species (Scheidegger & Werth 2009;Werth 2010).…”

“…These terms characterize the taxonomic range of the partners with which an organism associates (Smith & Douglas 1987). Following the suggestion by Beck et al (2002), I use the term specificity for the symbiotic association as a whole, that is, from the view of both photobionts and mycobionts. A narrow taxonomic range (e.g., a one-to one relationship) would be indicative of the high specificity of the association.…”

Anatomical, physiological and chemical differences between populations of Pseudocyphellaria flavicans (Hook. f. & Taylor) Vain. from Chile

“…This is also true for photobiont availability, which may determine the presence of a given species in a particular environment (Beck et al 2002, Yahr et al 2006, Fernández-Mendoza et al 2011, Vargas & Beck 2012, Nyati et al 2013. Total thallus, upper cortex, algal layer and medulla thickness, for example, are increased in lichens highly exposed to sunlight, and even an epinecral layer is formed as protection to high sun exposition in some cases (Büdel 1990, Gaya 2009).…”

Genetic diversity of sterile culturedTrebouxiaphotobionts associated with the lichen-forming fungusXanthoria parietinavisualized with RAPD-PCR fingerprinting techniques

“…Later, the photobiont diversity within thalli of conspecific lichen-forming fungi were biochemically analysed, the focus being on isoenzyme patterns (Kilias 1988;Kilias et al 1988;Fahselt 1989). With molecular techniques and algalspecific primers applied to whole lichen DNA, the photobionts can be conveniently identified at the species level without any isolation and culturing (Beck et al 1998;Friedl et al 2000;Dahlkild et al 2001;Helms et al 2001;Beck et al 2002). Thanks to this type of investigation our knowledge about the range of photobiont taxa associated with particular species of lichen-forming fungi has significantly increased in recent years.…”

“…In only a few studies was photobiont diversity examined within populations. Photobiont diversity was studied in lichen communities growing on heavy-metal rich rock (Beck et al 1998;Beck 1999;Beck et al 2002). Photobiont diversity was explored in the families Cladoniaceae (Piercey-Normore & DePriest 2001; Piercey-Normore 2004, Yahr et al 2004), Parmeliaceae (Piercey-Normore 2009) and Physciaceae (Dahlkild et al 2001;Helms et al 2001, Helms 2003, in the genera Caloplaca Th.…”