Diversity and abundance of resupinate thelephoroid fungi as ectomycorrhizal symbionts in Swedish boreal forests

Abstract

Resupinate thelephoroid fungi (hereafter called tomentelloid fungi) have a world-wide distribution and comprise approximately 70 basidiomycete species with inconspicuous, resupinate sporocarps. It is only recently that their ability to form ectomycorrhizas (EM) has been realized, so their distribution, abundance and significance as mycobionts in forest ecosystems is still largely unexplored. In order to provide baseline data for future ecological studies of tomentelloid fungi, we explored their presence and abundance in nine Swedish boreal forests in which the EM communities had been analysed. Phylogenetic analyses were used to compare the internal transcribed spacer of nuclear ribosomal DNA (ITS rDNA) sequence data obtained from mycobionts on single ectomycorrhizal tips with that obtained from sporocarps of identified tomentelloid fungi. Five species of Tomentella and one species of Pseudotomentella were identified as ectomycorrhizal fungi. The symbiotic nature of Tomentella bryophila, T. stuposa, T. badia and T. atramentaria is demonstrated for the first time. T. stuposa and Pseudotomentella tristis were the most commonly encountered tomentelloid fungi, with the other species, including T. sublilacina, only being recorded from single stands. Overall, tomentelloid fungi were found in five of the studies, colonizing between 1 and 8% of the mycorrhizal root tips. Two of the five sites supported several tomentelloid species. Tomentelloid fungi appear to be relatively common ectomycorrhizal symbionts with a wide distribution in Swedish coniferous forests. The results are in accordance with accumulating data that fungal species which lack conspicuous sporocarps may be of considerable importance in EM communities.

Ectomycorrhizal fungal communities of black spruce differ between wetland and upland forests

“…Cenococcum, MRA 1, and Cortinariaceae 1 morphotypes and genotypes occurred across both wet and dry habitats, whereas genotypes of Amphinema, Cortinariaceae 2, and Russulaceae 2 showed more uneven patterns of distribution. Habitat-and site-specific associations have also been reported for Amphinema and MRA -hybrid spruce ECMs, lodgepole pine ECMs, and tomentelloid types based on RFLP profiles and ITS sequences (Byrd et al 2000;Kõljalg et al 2000;Mah et al 2001).…”

“…The color, mantle features, and cystidia of Tomentella-like 1 were similar to those of dark-mantled types of Tomentella (Agerer 1987(Agerer -2002Lilleskov et al 2002) and those described from black spruce peatlands in northern Alberta (Thormann et al 1999). Thelephoraceae -conifer associations are well known and important components of ECM communities (Kõljalg et al 2000). Many form inconspicuous resupinate fruit bodies on dead plants, wood, and soil debris (Kõljalg 1996), and some have been functionally classified as decomposers (Read and Perez-Moreno 2003).…”

Ectomycorrhizal status of a mature productive black truffle plantation

“…Mycorrhizae of the Thelephoroid clade are very diverse, but they are recognised by their frequently brown or brownish colour and because they may possess blue granules that become greenish in KOH or hyphae can simply turn green in KOH, indicating the presence of thelephoric acid, also have thelephoroid rhizomorphs and emanating hyphae with or without clamps (Agerer, 2006;Kõljalg et al, 2000). Most of the types found in this work share some of those characters to identify them as Thelephoroid, or, at least, to recognize their Thelephoroid nature.…”

Le chaulage forestier influence durablement les communautés d’ectomycorrhizes et de carpophores épigés

“…In contrast, liming also promoted relative abundance of the two ECM morphotypes Clavulina cristata and Tomentella sublilacina in both spruce and beech plots. These two species have often been found in surveys of ECM root tips and are considered as ubiquist (Buée et al, 2005;Frey et al, 2004;Köljalg et al, 2000;Taylor and Bruns, 1999;Tedersoo et al, 2006). Moreover, Tomentella sublilacina is an excellent competitor in mature forests (Taylor and Bruns, 1999).…”