Community composition of arctic root-associated fungi mirrors host plant phylogeny

Abstract

The number of plant species regarded as non-mycorrhizal increases at higher latitudes, and several plant species in the High-Arctic Archipelago Svalbard have been reported as non-mycorrhizal. We used the rRNA ITS2 and 18S gene markers to survey which fungi, as well as other micro-eukaryotes, were associated with roots of 31 arctic plant species not usually regarded as mycorrhizal in Svalbard. We assessed to what degree the root-associated fungi showed any host preference and whether the phylogeny of the plant hosts may mirror the composition of root-associated fungi. Fungal communities were largely structured according to host plant identity and to a less extent by environmental factors. We observed a positive relationship between the phylogenetic distance of host plants and the distance of fungal community composition between samples, indicating that the evolutionary history of the host plants plays a major role for which fungi colonize the plant roots. In contrast to the ITS2 marker, the 18S rRNA gene marker showed that chytrid fungi were prevalently associated with plant roots, together with a wide spectrum of amoeba-like protists and nematodes. Our study confirms that arbuscular mycorrhizal (AM) fungi are present also in arctic environments in low abundance.

Host-Environment Interplay Shapes Fungal Diversity in Mosquitoes

“…do not persist in mosquito breeding grounds in Kansas and therefore remained undetected in our data set. However, an equally parsimonious explanation is a lack of detection due to the choice of primers that poorly capture early-diverging and basal fungal phyla ( 65 ). In future studies, we will therefore employ taxon-specific primers and microscopy techniques to assess the presence of Smittium spp.…”

Fungal biodiversity in Arctic paleoecosystems assessed by metabarcoding of lake sedimentary ancient DNA

“…Potential of lake sediment fungal DNA for paleoecology Fungi which are specific regarding their associations with plants or regarding other environmental conditions such as temperature may be indicative of local plant communities and climate, respectively. Based on the ecological conditions in the environment of the sampled lakes and on previous morphological and molecular studies in various ecosystems, we expected fungal taxa belonging to different ecological functional groups such as terrestrial saprotrophs, mycorrhiza fungi, coprophilous fungi, and aquatic taxa (Booth, 2011;Grau et al, 2017;Botnen et al, 2020) which may indicate ecosystem structures and environmental changes. Some examples of such ecosystem indicators are provided here, however, ecological interpretations of these data are made elsewhere (von Hippel et al, in prep.…”

Ecology and potential functions of plant-associated microbial communities in cold environments

“… 2014 ; Botnen et al . 2014 , 2020 ; Kauppinen et al . 2014 ; Zhang and Yao 2015 ; Mundra, Bahram and Eidesen 2016 ; Kumar et al .…”

“… 2011 ; Zhang and Yao 2015 ; Botnen et al . 2020 ), indicating host specificity of plant-associated fungal communities in Arctic environments. In particular, Cryptococcus , Rhizosphaera , Mycopappus , Melampsora , Tetracladium , Phaeosphaeria , Mrakia , Venturia and Leptosphaeria genera were consistently detected in association with Arctic plants (Zhang and Yao 2015 ).…”

“… 2020 ; Botnen et al . 2020 ) and environmental factors (e.g. mean annual temperature and precipitation, elevation, humus content, organic matter, bedrock type, phosphorus and nitrogen content and soil pH) can affect the taxonomic structure of fungal communities associated with Arctic plants (Fujimura and Egger 2012 ; Timling et al .…”