Genetic diversity of root‐associated fungal endophytes from Calluna vulgaris at contrasting field sites

Abstract

A total of 107 putative ericoid mycorrhizal endophytes were isolated from hair roots of Calluna vulgaris from two abandoned arsenic\copper mine sites and a natural heathland site in southwest England. The endophytes were initially grouped as 14 RFLP types, based on the results of ITS-RFLP analysis using the restriction endonucleases Hinf I, Rsa I and Hae III. ITS sequences were obtained for representative isolates from each RFLP type and compared phylogenetically with sequences for known ericoid mycorrhizal endophytes and selected ascomycetes. The majority of endophyte isolates (62-92%) from each site were identified as Hymenoscyphus ericae, but a number of other less common mycorrhizal RFLP types were also identified, all of which appear to have strong affinities with the order Leotiales. None of the less common RFLP types was isolated from C. vulgaris at more than one field site. Neighbour-joining analysis indicated similarities between the endophytes from C. vulgaris and mycorrhizal endophytes isolated from other Ericaceae and Epacridaceae hosts in North America and Australia.

Diversity of ericoid mycorrhizal fungi isolated from hair roots of Rhododendron obtusum var. kaempferi in a Japanese red pine forest

“…kaempferi in this forest. These diverse fungal taxa that form ericoid mycorrhizae in a single ericaceous species are also reported in roots of C. vulgaris in England (Sharples et al 2000), G. shallon in Canada (Monreal et al 1999), and Woollsia pungens (Cav.) F. Muell , Epacris impressa Labill, and Astroloma pinifolium (R.…”

“…Hymenoscyphus ericae has been often described as a ubiquitous mycorrhizal fungus of ericaceous plants in heathland (Read and Kerley 1999). Sharples et al (2000) reported that the majority of fungal isolates from roots of Calluna vulgaris L. Hull in heathland in southwest England were identified as H. ericae, and Oidiodendron species were not found. It seems that fungal communities of ericoid mycorrhiza in this red pine forest of Japan are different from those of heathland, and that H. ericae is not always the dominant mycorrhizal species.…”

“…Recent molecular analysis of the rDNA-internal transcribed spacer (ITS) region have clarified their phylogenetic relationship and exhibited the genetic diversity of ericoid mycorrhizal fungi (Liu et al 1998;Chambers et al 1999Chambers et al , 2000McLean et al 1999;Monreal et al 1999;Sharples et al 2000).…”

Mycorrhizal and Endophytic Fungi of Epacrids (Ericaceae)

“…ITS sequence data suggest that many of the endophytes are Helotiales ascomycetes, several of which have affinities with the Hymenoscyphus ericae aggregate (McLean et al 1999;Chambers et al 2000;Sharples et al 2000;Cairney and Ashford 2002). This aggregate encompasses H. ericae, Phialophora finlandia and related taxa, many of which form ericoid mycorrhiza with northern hemisphere Ericaceae (Vrålstad et al 2002).…”

“…These isolates have been obtained from epacrids at alpine, dry sclerophyll forest, sand mine and coastal heathland sites, indicating that they have a widespread distribution in a variety of Australian habitats (McLean et al 1998(McLean et al , 1999Midgley et al 2002). Many of the other endophytes are part of a poorly defined Helotiales ascomycete group that probably incorporates a number of taxa and includes many ericoid mycorrhizal and other root-associated fungi from northern hemisphere Ericaceae (McLean et al 1999;Chambers et al 2000;Sharples et al 2000;Cairney and Ashford 2002;Berch et al 2002;Midgley et al 2002Midgley et al , 2004a. Other isolates had closest ITS sequence similarity to Capronia (Chaetothyriales) and Thielavia (Sordariales) (Midgley et al 2002(Midgley et al , 2004a, and, while some of these are also endophytes of nonericaceae hosts, similar isolates are known to form ericoid mycorrhiza with Gaultheria shallon in Canada (Berch et al 2002).…”