Ericoid Mycorrhizas Research Articles

Implications of evergreen shrub expansion in the Arctic

Abstract Arctic shrub expansion is occurring across large parts of the tundra biome and its potential ecological repercussions have been widely discussed. But while the term “shrub expansion” often implicitly refers to an increase in tall, deciduous species such as birch and willow, several studies have also found a strong increase in evergreen dwarf shrubs in response to warming, a fact which has received far less attention. The effects of an evergreen dwarf shrub expansion are markedly different from the effects of an increase in taller, deciduous species. While deciduous shrubs may increase carbon (C) cycling through changes in albedo, litter input, and snow depth, the low stature of evergreen dwarf shrubs means that they are unlikely to influence snow cover. They also produce more recalcitrant litter, which reduces microbial activity. Furthermore, recent research suggests that ericoid mycorrhiza associated with evergreen shrubs may help to decelerate litter and soil organic matter turnover rates through the production of melanized hyphae that resist decomposition. Through selective browsing, herbivores may promote evergreen shrubs and facilitate C storage. Synthesis. In this mini review, we argue that basing predictions of how shrub expansion will affect tundra ecosystems on characteristics only applicable to tall deciduous shrubs hampers our understanding of the complex feedbacks related to Arctic vegetation shifts.

Perkembangan Penelitian Mikoriza di Papua**

The mycorrhizas are ‘balanced’ mutualistic associations in which the fungus and plant exchange commodities required for their growth and survival. The are many type of mycorrhizal namely endomycorrhiza, ectomycorrhiza, Orchid-mycorrhiza, ericoid mycorrhiza, and ectendo mycorrhiza. Most research is in endo and ectomycorrhiza, due to their role in Papua. Research in mycorrhiza has also been done recently. The research started in 2005 with ectomycorrhiza studies conducted by Suharno & Sufaati. Study on endomycorrhiza were begin in 2006 and orchid mycorrhiza in 2007. Exploration study of endomycorrhiza in corn plant at Koya Barat showed that there were 7 species of VAM namely Glomus sp1., Glomus sp2., Glomus sp3., Gigaspora sp., Acaulospora., Scutellospora sp1., and Scutellospora sp2. Similar research have also been done on other agriculture comodity, and the weed as well. Study on the endomycorrhiza associated with matoa (Pometia pinnata) found 13 species. Furtheremore, preliminary research on ectomycorrhiza showed that at least four species have been found at Mount Cycloops Nature Reserve, Jayapura. In Papua, there were 18 strain isolate of  Scleroderma have been collected and 4 species were already identified. For orchid-mycorrhiza there were only 17 species has been found so far. Among them there species were identified: Rhizoctonia sp., Tulasnella sp., dan Ceratorhiza sp. The potency of mycorrhiza in Papua is high and need to be explored. Some isolate were already tested to variety of the growth of plant. The result showed that the isolate affected significantly. More exploration, compatibility test, and the role of mycorrhiza will be continued to study. The goals of all the study here was to find a good quality of isolate that can be used as a propagule to produce biofertilizer.Key words: endomycorrhiza, ectomycorrhiza, orchid-mycorrhiza, biofertilizer, Papua.Â

The root-symbiotic Rhizoscyphus ericae aggregate and Hyaloscypha (Leotiomycetes) are congeneric: Phylogenetic and experimental evidence.

Data mining for a phylogenetic study including the prominent ericoid mycorrhizal fungus Rhizoscyphus ericae revealed nearly identical ITS sequences of the bryophilous Hyaloscypha hepaticicola suggesting they are conspecific. Additional genetic markers and a broader taxonomic sampling furthermore suggested that the sexual Hyaloscypha and the asexual Meliniomyces may be congeneric. In order to further elucidate these issues, type strains of all species traditionally treated as members of the Rhizoscyphus ericae aggregate (REA) and related taxa were subjected to phylogenetic analyses based on ITS, nrLSU, mtSSU, and rpb2 markers to produce comparable datasets while an in vitro re-synthesis experiment was conducted to examine the root-symbiotic potential of H. hepaticicola in the Ericaceae. Phylogenetic evidence demonstrates that sterile root-associated Meliniomyces, sexual Hyaloscypha and Rhizoscyphus, based on R. ericae, are indeed congeneric. To this monophylum also belongs the phialidic dematiaceous hyphomycetes Cadophora finlandica and Chloridium paucisporum. We provide a taxonomic revision of the REA; Meliniomyces and Rhizoscyphus are reduced to synonymy under Hyaloscypha. Pseudaegerita, typified by P. corticalis, an asexual morph of H. spiralis which is a core member of Hyaloscypha, is also transferred to the synonymy of the latter genus. Hyaloscypha melinii is introduced as a new root-symbiotic species from Central Europe. Cadophora finlandica and C. paucisporum are confirmed conspecific, and four new combinations in Hyaloscypha are proposed. Based on phylogenetic analyses, some sexually reproducing species can be attributed to their asexual counterparts for the first time whereas the majority is so far known only in the sexual or asexual state. Hyaloscypha bicolor sporulating in vitro is reported for the first time. Surprisingly, the mycological and mycorrhizal sides of the same coin have never been formally associated, mainly because the sexual and asexual morphs of these fungi have been studied in isolation by different research communities. Evaluating all these aspects allowed us to stabilize the taxonomy of a widespread and ecologically well-studied group of root-associated fungi and to link their various life-styles including saprobes, bryophilous fungi, root endophytes as well as fungi forming ericoid mycorrhizae and ectomycorrhizae.

Organic matter removal associated with forest harvest leads to decade scale alterations in soil fungal communities and functional guilds

Intensive organic matter removal (OMR) associated with timber harvest has the potential to impart long-term alterations to soil biota and associated properties and processes; however, there is a lack of data to say if this trend persists at depth. This study investigated how OMR influences long-term stability of soil fungi to a depth of 1 m using a replicated experimental pine forest in the Gulf Coastal Plain, USA. Treatments included unharvested control stands as well as low- and high-OMR stands. Intensive OMR led to significant differences in community structure and the abundance of functional guilds in surficial soil. Saprophytic taxa increased while ectomycorrhizal (ECM) taxa decreased with intensive-OMR, which correlated strongly with increased surface temperature and reduced soil nitrogen. Ericoid mycorrhizae (ERM) also increased in intensive-OMR stands, which may indicate that following disturbance, ERM could outcompete ECM for colonization of subsequent seedlings. Overall, no differences were observed below 30 cm, except for alpha diversity, which was a function of high inter-replicate variability. Our results illustrate a distinct long-term structural and functional response of soil fungi to intensive-OMR in the upper portions of the soil profile, which could lead to altered stand productivity and ecosystem services.

Diversity and growth-effects of ectomycorrhizal fungi of a Nothofagus pumilio forest in the Andes of Southern Chile

Chilean temperate rainforests have unique climatic, edaphic and biotic conditions, constituting pre-industrial blueprint ecosystems. Mycorrhizal associations play a central role in the biogeochemical processes of these ecosystems´ functioning. Baseline forest ecology studies are necessary in order to better understand diversity patterns, specifically regarding mycorrhizal symbiosis. Therefore, here we described the vegetation characteristics and the mycorrhizal relationships of vascular plants in a Nothofagus pumilio forest. We also described, via morphological methods, the ectomycorrhizal diversity present in this forest. Additionally, we determined whether ectomycorrhizal inoculations confer positive growth effects on N. pumilio seedlings. We founded that from 46 described vascular plant species, 42 (91%) were associated with mycorrhizae and of these 33 (72%) were associated with arbuscular mycorrhizae (AM), two (the dominant trees N. pumilio and N. dombeyi ) were associated with ectomycorrhizae (EM), five were associated with ericoid mycorrhizae, two with orchid mycorrhizae, and four were non-mycorrhizal. Additionally, 26 EM species were detected of which 14 belong to Cortinarius . Finally, there were clear differences in the growth of N. pumilio seedlings inoculated with the ectomycorrhizal fungus Laccaria laccata compared to non-inoculated plants. We suggest that mycorrhizal fungi play a key role in seedling colonization of extreme environments such as the Andean treeline.

The Hydrophobin-Like OmSSP1 May Be an Effector in the Ericoid Mycorrhizal Symbiosis.

Mutualistic and pathogenic plant-colonizing fungi use effector molecules to manipulate the host cell metabolism to allow plant tissue invasion. Some small secreted proteins (SSPs) have been identified as fungal effectors in both ectomycorrhizal and arbuscular mycorrhizal fungi, but it is currently unknown whether SSPs also play a role as effectors in other mycorrhizal associations. Ericoid mycorrhiza is a specific endomycorrhizal type that involves symbiotic fungi mostly belonging to the Leotiomycetes (Ascomycetes) and plants in the family Ericaceae. Genomic and RNASeq data from the ericoid mycorrhizal fungus Oidiodendron maius led to the identification of several symbiosis-upregulated genes encoding putative SSPs. OmSSP1, the most highly symbiosis up-regulated SSP, was found to share some features with fungal hydrophobins, even though it lacks the Pfam hydrophobin domain. Sequence alignment with other hydrophobins and hydrophobin-like fungal proteins placed OmSSP1 within Class I hydrophobins. However, the predicted features of OmSSP1 may suggest a distinct type of hydrophobin-like proteins. The presence of a predicted signal peptide and a yeast-based signal sequence trap assay demonstrate that OmSSP1 is secreted. OmSSP1 null-mutants showed a reduced capacity to form ericoid mycorrhiza with Vaccinium myrtillus roots, suggesting a role as effectors in the ericoid mycorrhizal interaction.

Effects of fragmentation on the plant functional composition and diversity of remnant woodlands in a young and rapidly expanding city

AbstractQuestionsHow do plant functional trait abundance and diversity in urban remnants of a rapidly urbanizing city change with fragmentation? Is there a delayed functional response to fragmentation?LocationThirty remnant Banksia woodlands, Perth, Australia.MethodsWe used GLMM to examine the effects of remnant age and area, and their interaction, on the relative abundance and functional diversity (FD) of five plant functional traits: growth form, pollination, seed dispersal, nutrient acquisition and regeneration strategies. We then used fourth‐corner analysis to examine the influence of a wider set of fragmentation‐related factors on trait abundances.ResultsThe functional composition and diversity of Banksia woodlands changed with remnant age, particularly in the smaller remnants. Plants more prone to decline with remnant age were the growth form shrubs, root‐clustered trees, herbaceous obligate seeders and understorey species that are insect‐pollinated, have seeds dispersal internally by animals and have arbuscular or ericoid mycorrhizas. In contrast, plants more prone to persist were growth forms trees, sedges and rushes, ectomycorrhizal trees, herbaceous resprouters, wind‐pollinated and root‐clustered understorey species. FD increased with remnant age in the growth forms and overstorey, but declined among the herbaceous and shrub pollination and nutrient acquisition traits.ConclusionsFunctional traits that consistently signalled the plant community response to fragmentation were growth form, pollination and dispersal. This functional response was largely delayed, suggesting a ″functional extinction debt″, which will lead to a further decline of plants with vulnerable trait states in the future, especially in the small‐ and medium‐sized remnants. Our study illustrates the vulnerability of small remnants to changes in community assembly and ecosystem function due to fragmentation. Furthermore, it exemplifies how a functional trait approach is valuable to understand the impacts of urbanization on remnant plant communities, before local extinctions may occur. Finally, the study shows how cities’ fragmentation history and biogeographic settings provide an important context influencing plant functional responses to urbanization‐related processes.

From rhizoids to roots? Experimental evidence of mutualism between liverworts and ascomycete fungi.

The rhizoids of leafy liverworts (Jungermanniales, Marchantiophyta) are commonly colonized by the ascomycete fungus Pezoloma ericae. These associations are hypothesized to be functionally analogous to the ericoid mycorrhizas (ErMs) formed by P. ericae with the roots of Ericaceae plants in terms of bi-directional phosphorus for carbon exchange; however, this remains unproven. Here, we test whether associations between the leafy liverwort Cephalozia bicuspidata and P. ericae are mutualistic. We measured movement of phosphorus and carbon between C. bicuspidata and P. ericae using [33P]orthophosphate and 14CO2 isotope tracers in monoxenic cultures. We also measured leafy liverwort growth, with and without P. ericae. We present the first demonstration of nutritionally mutualistic symbiosis between a non-vascular plant and an ErM-forming fungus, showing transfer of fungal-acquired P to the liverwort and of liverwort-fixed C to the fungus alongside increased growth in fungus-colonized liverworts. Thus, this ascomycete-liverwort symbiosis can now be described as mycorrhiza-like, providing further insights into ericoid mycorrhizal evolution and adding Ascomycota fungi to mycorrhizal fungal groups engaging in mutualisms with plants across the land plant phylogeny. As P. ericae also colonizes the rhizoids of Schistochilaceae liverworts, which originated in the Triassic and are sister to all other jungermannialean liverworts associated with fungi, our findings point toward an early origin of ascomycete-liverwort symbioses, possibly pre-dating their evolution in the Ericales by some 150 million years.

When the ribosomal DNA does not tell the truth: The case of the taxonomic position of Kurtia argillacea, an ericoid mycorrhizal fungus residing among Hymenochaetales

The nuclear ribosomal DNA (nuc-rDNA) is widely used for the identification and phylogenetic reconstruction of Agaricomycetes. However, nuc-rDNA-based phylogenies may sometimes be in conflict with phylogenetic relationships derived from protein coding genes. In this study, the taxonomic position of the basidiomycetous mycobiont that forms the recently discovered sheathed ericoid mycorrhiza was investigated, because its nuc-rDNA is highly dissimilar to any other available fungal sequences in terms of nucleotide composition and length, and its nuc-rDNA-based phylogeny is inconclusive and significantly disagrees with protein coding sequences and morphological data. In the present work, this mycobiont was identified as Kurtia argillacea (= Hyphoderma argillaceum) residing in the order Hymenochaetales (Basidiomycota). Bioinformatic screening of the Kurtia ribosomal DNA sequence indicates that it represents a gene with a non-standard substitution rate or nucleotide composition heterogeneity rather than a deep paralogue or a pseudogene. Such a phenomenon probably also occurs in other lineages of the Fungi and should be taken into consideration when nuc-rDNA (especially that with unusual nucleotide composition) is used as a sole marker for phylogenetic reconstructions. Kurtia argillacea so far represents the only confirmed non-sebacinoid ericoid mycorrhizal fungus in the Basidiomycota and its intriguing placement among mostly saprobic and parasitic Hymenochaetales begs further investigation of its eco-physiology.

Effect of soil moisture on root-associated fungal communities of Erica dominans in Drakensberg mountains in South Africa.

Ericoid mycorrhiza represents a key adaptation of the Ericaceae plants to facilitate their establishment in harsh conditions. The Ericaceae are a large family of flowering plants, with global distribution. However, our current knowledge about the ericoid mycorrhizal fungal diversity and ecology largely relates to the Northern Hemisphere. Our study focused on the assembly of root-associated fungal (RAF) communities of Erica dominans in two types of microhabitats of contrasting moisture along an elevation gradient in Drakensberg mountains in South Africa. RAF communities were determined by 454-sequencing of the internal transcribed spacer (ITS) region of ribosomal DNA. The majority of RAF showed affinity to the orders Helotiales, Pezizales, and Pleosporales. Microhabitat type as well as elevation had significant but weak effect on RAF community composition. We identified two putative ericoid mycorrhizal fungi, the ecological niches of which were differentiated between the studied microhabitats. Our study also provides one of the first comprehensive data about RAF communities of Ericaceae on African continent and shows the occurrence of the most studied ericoid mycorrhizal fungus Pezoloma ericae (belonging to P. ericae aggregate) in roots of Ericaceae host plant in Africa.

Morphological and physicochemical traits of leaves of different life-forms of various broadleaf woody plants in interior Alaska

The morphological and physicochemical traits of leaves are important in terms of plant adaptation to various growth environments, because such traits play central roles in various functions including photosynthesis. We measured the toughness, mass per unit area (LMA), nitrogen content, and δ15N levels of the leaves of different life-forms of 39 broadleaf woody plants in interior Alaska. The plants were divided into three life-forms based on the maximum height of adult plants: understory (<1 m), small (≥1 m to <5 m), and canopy (≥5 m). Evergreen species accounted for a large proportion of understory woody plants (44%), whereas most small (87%) and canopy (100%) trees were deciduous. Higher LMA, increased toughness, and higher C-to-N ratios prolonged leaf life-span in evergreen species. We also evaluated the presence or absence of bundle-sheath extensions (BSEs), which contribute to the mechanical support of leaves and enhance photosynthetic ability by improving hydraulic properties. In total, 11 species (28%) had homobaric leaves (BSEs were absent) and 28 species (72%) had heterobaric leaves; these proportions are similar to those of woody plants of other temperate deciduous forests. The δ15N values reflected the presence of root symbionts such as ericoid mycorrhiza or Frankia sp. Our results suggest that leaf traits may affect both the life-form of the host plants and leaf longevity in both evergreen and deciduous species.

First record of Rhizoscyphus ericae in Southern Hemisphere's Ericaceae.

Ericoid mycorrhiza is arguably the least investigated mycorrhizal type, particularly when related to the number of potential hosts and the ecosystems they inhabit. Little is known about the global distribution of ericoid mycorrhizal (ErM) fungi, and this holds true even for the prominent ErM mycobiont Rhizoscyphus ericae. Earlier studies suggested R. ericae might be low in abundance or absent in the roots of Southern Hemisphere's Ericaceae, and our previous investigations in two Argentine Patagonian forests supported this view. Here, we revisited the formerly investigated area, albeit at a higher altitude, and screened fungi inhabiting hair roots of Gaultheria caespitosa and Gaultheria pumila at a treeless alpine site using the same methods as previously. We obtained 234 isolates, most of them belonging to Ascomycota. In contrast to previous findings, however, among 37 detected operational taxonomic units (OTUs), OTU 1 (=R. ericae s. str.) comprised the highest number of isolates (87, ∼37%). Most of the OTUs and isolates belonged to the Helotiales, and 82.5% of isolates belonged to OTUs shared between both Gaultheria species. At the alpine site, ericoid mycorrhizal fungi dominated, followed by dark septate endophytes and aquatic hyphomycetes probably acting as root endophytes. Our results suggest that the distribution of R. ericae is influenced, among others, by factors related to altitude such as soil type and presence/absence and type of the neighboring vegetation. Our study is the first report on R. ericae colonizing Ericaceae roots in the Southern Hemisphere and extends the known range of this prominent ErM species to NW Patagonia.

The contribution of ericoid plants to soil nitrogen chemistry and organic matter decomposition in boreal forest soil

Nitrogen (N) availability restricts plant carbon assimilation from the atmosphere in N-limited boreal ecosystems. Boreal forest floor is covered with ericoid plants and in soil, ectomycorrhizal and ericoid mycorrhizal plant roots and fungal hyphae are intermixed. How different mycorrhizal plants affect N mobilization from soil organic matter (SOM) has yet to be elucidated. Here we compared the effects of ericoid plants (Calluna vulgaris, Vaccinium myrtillus, Vaccinium vitis-idaea), forming ericoid mycorrhiza (ERM), on soil N chemistry, plant N uptake and SOM decomposition and compared them with ectomycorrhizal (ECM) Pinus sylvestris in a microcosm experiment. Pine and ericoid plants affected soil N similarly, accessing both degradable and recalcitrant N pools. Both ericoid plants and pine took up N from organic source. Ericoid plant roots contained more phenolic compounds and condensed tannins than pine roots which together with lower pH under ericoids suggests substantial changes in soil chemistry and biology. This study underlines the plant stimulation of SOM degradation with special emphasis on ericoid plants. We point out that both ericoid and ectomycorrhizal plants and their interactions should be of interest when N uptake and SOM decomposition in boreal forests are studied.

Mycorrhizas and soil ecosystem function of co-existing woody vegetation islands at the alpine tree line

Background and aimsPicea abies, Pinus mugo and Rhododendron ferrugineum co-exist at the alpine tree line, and can have different mycorrhizal communities. The activity and diversity of mycorrhizal fungi are considered to be important factors in regulation of soil function.MethodsAt a tree line site and a lower elevation site in the Austrian Alps, the community structure of ectomycorrhiza on Picea abies and Pinus mugo was determined. The activity of surface enzymes was determined on ectomycorrhizal and ericoid mycorrhizal roots. In soils, the activity of a range of enzymes, nitrogen (N) mineralization and biomass decomposition were determined.ResultsThe community structure of the ectomycorrhizal community of Picea abies and Pinus mugo differed strongly, but the average activity of surface enzymes of the ectomycorrhizal communities was similar. A lower root surface enzyme activity was determined on Rhododendron ferrugineum. Soil N-mineralization under Rhododendron ferrugineum was significantly lower than under Picea abies and Pinus mugo. In soil, the activity of a range of enzymes did not differ at the tree line but differed between the tree line and the lower elevation sites.ConclusionThe different ectomycorrhizal communities on Picea abies and Pinus mugo and ericoid mycorrhizas on Rhododendron ferrugineum support similar ecosystem functions in soil.

Ericoid fungal diversity: Challenges and opportunities for mycorrhizal research

Abstract Ericoid mycorrhiza occur only within the plant family Ericaceae, yet are globally widespread and contribute to carbon and nutrient cycling in many habitats where harsh conditions limit decomposition and plant nutrient uptake. An increasingly diverse range of fungi are recognized as ericoid symbionts and patterns in the distribution of ericoid taxa are beginning to emerge across scales. However, the true diversity of ericoid mycorrhizal fungi remains unresolved due to limited sampling from some regions and challenges associated with delineating mycorrhizal taxa from the broader fungal community associated with ericoid plants. Interpreting patterns in the diversity and distributions of ericoid mycorrhizal fungi will ultimately require improved understanding of their functional ecology and functional diversity, which is currently limited to a few well studied species. Fortunately, many ericoid taxa are amenable to experimental manipulation and continued ericoid mycorrhizal research promises to improve general understanding of the ecology and evolution of mycorrhizal symbioses.

Experimental evidence of ericoid mycorrhizal potential within Serendipitaceae (Sebacinales).

The Sebacinales are a monophyletic group of ubiquitous hymenomycetous mycobionts which form ericoid and orchid mycorrhizae, ecto- and ectendomycorrhizae, and nonspecific root endophytic associations with a wide spectrum of plants. However, due to the complete lack of fungal isolates derived from Ericaceae roots, the Sebacinales ericoid mycorrhizal (ErM) potential has not yet been tested experimentally. Here, we report for the first time isolation of a serendipitoid (formerly Sebacinales Group B) mycobiont from Ericaceae which survived in pure culture for several years. This allowed us to test its ability to form ericoid mycorrhizae with an Ericaceae host in vitro, to describe its development and colonization pattern in host roots over time, and to compare its performance with typical ErM fungi and other serendipitoids derived from non-Ericaceae hosts. Out of ten serendipitoid isolates tested, eight intracellularly colonized Vaccinium hair roots, but only the Ericaceae-derived isolate repeatedly formed typical ericoid mycorrhiza morphologically identical to ericoid mycorrhiza commonly found in naturally colonized Ericaceae, but yet different from ericoid mycorrhiza formed in vitro by the prominent ascomycetous ErM fungus Rhizoscyphus ericae. One Orchidaceae-derived isolate repeatedly formed abundant hyaline intracellular microsclerotia morphologically identical to those occasionally found in naturally colonized Ericaceae, and an isolate of Serendipita (= Piriformospora) indica produced abundant intracellular chlamydospores typical of this species. Our results confirm for the first time experimentally that some Sebacinales can form ericoid mycorrhiza, point to their broad endophytic potential in Ericaceae hosts, and suggest possible ericoid mycorrhizal specificity in Serendipitaceae.

Liverworts to the rescue: an investigation of their efficacy as mycorrhizal inoculum for vascular plants

Summary Pezoloma ericae (D.J. Read) Baral, a widespread mycorrhizal fungus of plants in the Ericales, is known to form intracellular associations with several families of leafy liverworts (Schistochilaceae, Lepidoziaceae, Cephaloziaceae, Cephaloziellaceae) in vitro. The ecological significance of this link between vascular and non‐vascular plants is unknown. Fungal symbionts were isolated from rhizoids of the leafy liverworts Cephalozia connivens (Dicks.) Lindb. and C. bicuspidata (L.) Dum. (Cephaloziaceae), as well as from the hair roots of two dominant ericoid mycorrhiza‐forming species of European heathlands, Erica tetralix (L.) and Calluna vulgaris (L.). Using pure cultures of P. ericae, we resynthesized liverwort–fungus associations to use colonized liverworts as inoculum which was applied to substrates supporting the growth of heather seedlings and cuttings. Effects were quantified using germination, rooting, plant colonization, plant survival under waterlogging stress and growth in height in experimental systems with and without liverworts and/or fungi. Fungal symbionts growing from liverwort rhizoids readily colonized the hair roots of ericaceous plants to form typical ericoid mycorrhizas. The presence of inoculum‐bearing liverworts led to significant increases in plant growth. Erica tetralix was more responsive to inoculation than C. vulgaris. Ericaceous cuttings rooted and survived more successfully when they were coplanted with previously colonized liverwort stems. We demonstrate, under realistic ecological circumstances, that liverworts can deliver mycorrhizal inoculum and improve the establishment of vascular plants. We propose that by providing sources of mycorrhizal inoculum, symbiotic non‐vascular plants can contribute to the restoration of plant communities dominated by Ericales plants. This research leads to broader knowledge about the function of ericoid mycorrhizas in ecosystems.

The potential of Dark Septate Endophytes to form root symbioses with ectomycorrhizal and ericoid mycorrhizal middle European forest plants.

The unresolved ecophysiological significance of Dark Septate Endophytes (DSE) may be in part due to existence of morphologically indistinguishable cryptic species in the most common Phialocephala fortinii s. l.—Acephala applanata species complex (PAC). We inoculated three middle European forest plants (European blueberry, Norway spruce and silver birch) with 16 strains of eight PAC cryptic species and other DSE and ectomycorrhizal/ericoid mycorrhizal fungi and focused on intraradical structures possibly representing interfaces for plant-fungus nutrient transfer and on host growth response. The PAC species Acephala applanata simultaneously formed structures resembling ericoid mycorrhiza (ErM) and DSE microsclerotia in blueberry. A. macrosclerotiorum, a close relative to PAC, formed ectomycorrhizae with spruce but not with birch, and structures resembling ErM in blueberry. Phialocephala glacialis, another close relative to PAC, formed structures resembling ErM in blueberry. In blueberry, six PAC strains significantly decreased dry shoot biomass compared to ErM control. In birch, one A. macrosclerotiorum strain increased root biomass and the other shoot biomass in comparison with non-inoculated control. The dual mycorrhizal ability of A. macrosclerotiorum suggested that it may form mycorrhizal links between Ericaceae and Pinaceae. However, we were unable to detect this species in Ericaceae roots growing in a forest with presence of A. macrosclerotiorum ectomycorrhizae. Nevertheless, the diversity of Ericaceae mycobionts was high (380 OTUs) with individual sites often dominated by hitherto unreported helotialean and chaetothyrialean/verrucarialean species; in contrast, typical ErM fungi were either absent or low in abundance. Some DSE apparently have a potential to form mycorrhizae with typical middle European forest plants. However, except A. applanata, the tested representatives of all hitherto described PAC cryptic species formed typical DSE colonization without specific structures necessary for mycorrhizal nutrient transport. A. macrosclerotiorum forms ectomycorrhiza with conifers but not with broadleaves and probably does not form common mycorrhizal networks between conifers with Ericaceae.

Colonization of blueberry (Vaccinium corymbosum) plantlets by ericoid mycorrhizae under nursery conditions

The ericoid mycorrhiza is a symbiotic interaction that contributes to the improvement of the establishment and production of blueberries ( Vaccinium corymbosum L.). The objectives of this paper were to assess the frequency (%) and intensity (%) of the colonization and growth of blueberry plantlets inoculated with ericoid mycorrhizae collected from three different edaphoclimatic conditions in the La Araucania region of southern Chile under nursery conditions. Plantlets of three blueberry cultivars (“Brigitta”, “Duke” and “Legacy”) were grown under nursery conditions in sterile peat moss and a vermiculite substrate with fresh ericoid mycorrhizae propagules from Gaultheria pumila (collected in Villarrica National Park), Azalea sp., (from an urban garden in Temuco) or V. corymbosum cv. “Brigitta” (from an organic farm in Temuco). After six months, the development of hyphae characteristic of ericoid micorrhizal fungi was identified in root cells. The frequency and intensity of colonization was greater in the “Duke” cv. given the inoculum derived from V. corymbosum , followed by the “Brigitta” and “Legacy” cultivars treated with inoculum from the G. pumila inoculum. Colonization was lowest in those plants treated with the Azalea sp . inoculum. Contact between the inoculum sources and the fine roots of the micro-propagated blueberry plantlets under nursery conditions for six months was an effective method to promote mycorrhization. However, the development of mycorrhizae did not enhance the growth of the three blueberry cultivars during the evaluation period. The possibility of selecting ericoid inocula from site-specific conditions in southern Chile may eventually be used to support the micro-propagation of blueberry plantlets during acclimation and planting, assuming that mycorrhizal plants will improve conditions for establishment in the field. La micorrizacion ericoide es una interaccion simbiotica que contribuye a mejorar el establecimiento y produccion de arandano ( Vaccinium corymbosum L.). Los objetivos fueron evaluar frecuencia (%) e intensidad (%) de colonizacion, y crecimiento de plantulas de arandano inoculadas en vivero con micorrizas ericoides colectadas desde tres condiciones edafoclimaticas en la Region de La Araucania, Chile. En condiciones de invernadero, plantulas de tres cultivares de arandano fueron establecidas en sustrato de turba esteril y vermiculita mezclada con propagulos frescos de micorrizas ericoides provenientes de Gaultheria pumila (Parque Nacional Villarrica) Azalea sp. , (Jardin Ornamental en Temuco)y de V. corymbosum cv “Brigitta” (plantacion organica en Temuco). Trascurrido seis meses, se constato en celulas de raices finas el desarrollo de hifas en forma de ovillo caracteristico de hongos micorricicos ericoides, cuya frecuencia e intensidad de colonizacion fue mayor en el cv. Duke con inoculo de V. corymbosum , seguido de “Brigitta” y “Legacy” con inoculo de G.pumila , en tanto que la colonizacion fue menor con inoculo de Azalea sp ., el contacto de las fuentes de inoculo con raicillas de plantulas de arandano micropropagadas en vivero durante seis meses, fue una opcion de micorrizacion eficaz; no obstante y como era esperable no se detecto efecto en el crecimiento de las plantulas de los tres cultivares de arandano durante el periodo de evaluacion. La posibilidad de utilizar inoculos ericoides obtenidos de plantas ericaceas del sur de Chile, seria una opcion eficaz de micorrizacion para mejor aclimatacion y establecimiento de arandano en diferentes condiciones de campo.

Colonization of blueberry (Vaccinium corymbosum) plantlets by ericoid mycorrhizae under nursery conditions

The ericoid mycorrhiza is a symbiotic interaction that contributes to the improvement of the establishment and production of blueberries ( Vaccinium corymbosum L.). The objectives of this paper were to assess the frequency (%) and intensity (%) of the colonization and growth of blueberry plantlets inoculated with ericoid mycorrhizae collected from three different edaphoclimatic conditions in the La Araucania region of southern Chile under nursery conditions. Plantlets of three blueberry cultivars (“Brigitta”, “Duke” and “Legacy”) were grown under nursery conditions in sterile peat moss and a vermiculite substrate with fresh ericoid mycorrhizae propagules from Gaultheria pumila (collected in Villarrica National Park), Azalea sp., (from an urban garden in Temuco) or V. corymbosum cv. “Brigitta” (from an organic farm in Temuco). After six months, the development of hyphae characteristic of ericoid micorrhizal fungi was identified in root cells. The frequency and intensity of colonization was greater in the “Duke” cv. given the inoculum derived from V. corymbosum , followed by the “Brigitta” and “Legacy” cultivars treated with inoculum from the G. pumila inoculum. Colonization was lowest in those plants treated with the Azalea sp . inoculum. Contact between the inoculum sources and the fine roots of the micro-propagated blueberry plantlets under nursery conditions for six months was an effective method to promote mycorrhization. However, the development of mycorrhizae did not enhance the growth of the three blueberry cultivars during the evaluation period. The possibility of selecting ericoid inocula from site-specific conditions in southern Chile may eventually be used to support the micro-propagation of blueberry plantlets during acclimation and planting, assuming that mycorrhizal plants will improve conditions for establishment in the field. La micorrizacion ericoide es una interaccion simbiotica que contribuye a mejorar el establecimiento y produccion de arandano ( Vaccinium corymbosum L.). Los objetivos fueron evaluar frecuencia (%) e intensidad (%) de colonizacion, y crecimiento de plantulas de arandano inoculadas en vivero con micorrizas ericoides colectadas desde tres condiciones edafoclimaticas en la Region de La Araucania, Chile. En condiciones de invernadero, plantulas de tres cultivares de arandano fueron establecidas en sustrato de turba esteril y vermiculita mezclada con propagulos frescos de micorrizas ericoides provenientes de Gaultheria pumila (Parque Nacional Villarrica) Azalea sp. , (Jardin Ornamental en Temuco)y de V. corymbosum cv “Brigitta” (plantacion organica en Temuco). Trascurrido seis meses, se constato en celulas de raices finas el desarrollo de hifas en forma de ovillo caracteristico de hongos micorricicos ericoides, cuya frecuencia e intensidad de colonizacion fue mayor en el cv. Duke con inoculo de V. corymbosum , seguido de “Brigitta” y “Legacy” con inoculo de G.pumila , en tanto que la colonizacion fue menor con inoculo de Azalea sp ., el contacto de las fuentes de inoculo con raicillas de plantulas de arandano micropropagadas en vivero durante seis meses, fue una opcion de micorrizacion eficaz; no obstante y como era esperable no se detecto efecto en el crecimiento de las plantulas de los tres cultivares de arandano durante el periodo de evaluacion. La posibilidad de utilizar inoculos ericoides obtenidos de plantas ericaceas del sur de Chile, seria una opcion eficaz de micorrizacion para mejor aclimatacion y establecimiento de arandano en diferentes condiciones de campo.