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Social Impact Statement: Vanilla planifolia is the source of the spice vanilla. This study is part of an international initiative to study the biology, including mycorrhizal fungi and cultivation practices of vanilla to improve its production in Mexico. The study focused on documenting mycorrhizal fungal diversity in vanilla. It also provided preliminary data on differences in mycorrhizal fungal communities associated with cultivation practices. A richer mycorrhizal community was observed in vanilla growing in a wild natural farm compared with those from a highly managed farm. Our research provides insights for sustainable vanilla production that can benefit Mexican farming communities. Summary: Relatively little is known regarding differences in root symbionts (i.e., mycorrhizae) between epiphytic and terrestrial orchids. We characterized the mycorrhizal fungal communities of aerial and terrestrial roots of the orchid, Vanilla planifolia, from four Mexican farms representing different management systems.Amplicon sequencing identified 40 putative mycorrhizal fungi based on ITS sequence data, these included traditional orchid mycorrhizal fungi such as Ceratobasidium, and Thanatephorus in the order Cantharellales as well as Serendipitaceae in the order Sebacinales, and species of several genera traditionally considered as ectomycorrhizal fungi. Mycorrhizal fungal communities were similar in aerial and terrestrial roots, but differed in read abundances.Plants growing in wild‐natural conditions hosted a richer, but not statistically different, community of mycorrhizal fungi in comparison with plants in the highly managed farm. Soil characteristics including texture, organic matter, N, P, and K do not explain differences between fungal communities at these farms.This is one of the first reports of a diverse community of fungi traditionally considered to form ectomycorrhizas in association with aerial orchid roots. Further research is needed to understand the functional role of these putative mycorrhizal fungi in the ecology of V. planifolia, and if ectomycorrhizal fungi commonly occur in other hemiepiphytic and epiphytic orchids. [ABSTRACT FROM AUTHOR]

Background and Aims: Introducing exotic tree species for afforestation out of their natural range may alter the local ectomycorrhizal (ECM) fungal communities. The potential functional consequences shaped by exotic trees with recruited local ECM fungi rather than native trees remain unclear. This study examined (a) whether the composition and extracellular enzyme function of ECM fungal communities differed between native masson pine (Pinus massoniana) and exotic slash pine (Pinus elliottii) during seedling establishment; and (b) how differences in enzyme functioning were linked to the growth pattern of the host plants. Methods: Native (masson) and exotic (slash) pine seedlings were planted into soil cores collected from each study site. At three months growth, root tips were collected from seedlings and assayed for ECM fungal community composition using high-throughput sequencing, and functioning using single root tip assays for enzymes associated with N, P and C acquisition. Results: ECM fungi on masson pines showed higher activities of nitrogen- (N-acetylglucosaminidase, 280–300%), phosphorus- (acid phosphatase, 105–152%), and cellulose (β-glucosidase, 204–235%; cellobiohydrolase, 142–255%) compound degrading enzymes compared to those on slash pines. Those differences was attributed to the host-specific performance of certain ECM fungal taxa, such as Rhizopogon spp. Information theory model selection showed that plant nutrient status in masson pines was correlated with the enzymatic contribution of Rhizopogon spp., whereas slash pines depended on a diverse enzyme palette from multiple ECM fungal taxa. Conclusions: Host identity strongly influenced ECM fungal community composition and extracellular enzymatic functions of specific ECM fungal taxa, which could feedback to host establishment and nutrient cycling processes of restored ecosystem. Therefore, the origin of afforestation tree species should be an important factor when selecting tree species for restoration of degraded lands. [ABSTRACT FROM AUTHOR]

Article impact statement: Conservation mycology is a newly introduced discipline relevant to conservation biologists, mycologists, ecologists, and conservation policy. [ABSTRACT FROM AUTHOR]

Species of Laccaria (Hydnangiaceae, Basidiomycota) are important in forest ecosystems as ectomycorrhizal fungi. Nine of the 75 described Laccaria species worldwide been reported from Korea. Most of these have European and North American names, and their identities are based solely on morphological features. To evaluate the taxonomy of Korean Laccaria, we used 443 specimens collected between 1981 and 2016 in a phylogenetic analysis based on sequence data from nuc rDNA internal transcribed spacer ITS1-5.8S-ITS2 rDNA (ITS) region, nuc 28S rDNA (28S), RNA polymerase II subunit 2 (rpb2), and translation elongation factor 1-α (tef1). Ten Laccaria species were identified. Three of these were previously reported from Korea: L. bicolor, L. tortilis, and L. vinaceoavellanea. Laccaria alba, L. japonica, and L. murina are confirmed as new reports from Korea. Lastly, four new Laccaria species are described: L. araneosa, L. parva, L. torosa, and L. versiforma. This study supports the general contention that Asian species of ectomycorrhizal fungi may not be conspecific with morphologically similar species from Europe and North America. Furthermore, identification based on morphology alone is often unreliable in Laccaria due to considerable overlap of characters among species. Thus, use of molecular methods is necessary for effective identification. Illustrations of the four newly described species and a taxonomic key to species of Laccaria in Korea are provided. [ABSTRACT FROM AUTHOR]

Craterellus olivaceoluteus sp. nov. and Craterellus cinereofimbriatus sp. nov. are described as new to science. These fungi were collected from Guyana in association with ectomycorrhizal host trees in the genera Dicymbe (Fabaceae subfam. Caesalpinioideae) and Pakaraimaea (Dipterocarpaceae). Cantharellus ffuyanensis Mont., originally described from French Guiana, is redescribed from recent collections from Guyana, with additional range extensions for the species provided based on material examined from French Guiana, Venezuela, and north central, northeastern and southern Brazil, circumscribing nearly the entire Guiana Shield region and beyond. A new distribution record from French Guiana is provided for Craterellus excelsus T.W. Henkel & Aime. Macromorphological, micromorphological and habitat data are provided for the new species and C. guyanensis as well as DNA sequence data from the nuclear ribosomal regions of the internal transcribed spacer (ITS) and 28S large subunit (LSU); additional sequence data is provided for C. guyanensis and C. excelsus specimens collected outside Guyana. The relationships of these taxa within the Cantharellaceae were evaluated with phylogenetic analyses of ITS and LSU sequence data. This work brings the total number of Cantharellaceae species known from Guyana to eight. A key to the Cantharellus and Craterellus species known from the lowland Neotropics and extralimital montane Central and South America is provided. [ABSTRACT FROM AUTHOR]

• EcM fungal richness differed more between elevated N-ambient than abated N-ambient • EcM fungal richness declined with increased soil N. • EcM soil fungal richness was two-fold greater than hyphal or root-tip richness. • Exploration type: why "nitrophilic" taxa flourish in conditions limiting other taxa. Atmospheric nitrogen (N) pollution visibly and rapidly changes forest systems, for example impacting the diversity of forest ectomycorrhizal (EcM) fungi. EcM fungi are measurable by components that vary in longevity, hence, reflecting different temporal scales of presence: EcM root-tips are viable for, at most, a couple growing seasons, compared to fungal structures that may persist in soil as DNA for decades or longer. In-growth mesh bags, in contrast, typically capture a single growing season of hyphal growth. The different components might portray different diversity responses by EcM fungi to large-scale N pollution, as well as any subsequent reductions from improved environmental standards. Within an established oak forest study system, we examined the impact of sustained and recently reduced experimental N addition on EcM fungal diversity and composition, measured in three main fungal components (root-free soil, root-tips, and mesh bag hyphae). We hypothesized that elevated soil N would reduce EcM fungal diversity, and that composition would change, but with differences among fungal components related to the temporal longevity of the components. Our expectations were largely met, in that richness primarily declined with increased soil N, and all trends were most pronounced with the soil EcM fungi (the only component potentially reflective of long-term fungal presence). We discovered that abatement of the experimental N treatment did not revert fungal trends to those of the same-site plots with ambient N treatment. Instead, the stochastic nature of local-scale disturbances, related to invasive earthworms and forest stand dynamics, likely impacted N levels and, thus, EcM fungal trends. Due to the context-dependency of localized disturbance(s), assessing the effects of reduced large-scale N deposition on EcM fungi can prove to be challenging. [ABSTRACT FROM AUTHOR]

Focuses on a study that explored the Costa Rican species of Leccinum. Connection of the mycelium of Leccinum with ectomycorrhizal tree roots; Habitat and distribution of Leccinum eximium; Etymology of Leccinum monicola.

Exotic non-native Pinus species have been widely planted or become naturalized in many parts of the world. Pines rely on ectomycorrhizal (ECM) fungi mutualisms to overcome barriers to establishment, yet the degree to which host specificity and edaphic preferences influence ECM community composition remains poorly understood. In this study, we used high-throughput sequencing coupled with soil analyses to investigate the effect of host plant identity, spatial distance and edaphic factors on ECM community composition in young (30-year-old) native (Pinus massoniana Lamb.) and exotic (Pinus elliottii Engelm.) pine plantations in China. The ECM fungal communities comprised 43 species with the majority belonging to the Thelephoraceae and Russulaceae. Most species were found associated with both host trees while certain native ECM taxa (Suillus) showed host specificity to the native P. massoniana. ECM fungi that are known to occur exclusively with Pinus (e.g., Rhizopogon) were uncommon. We found no significant effect of host identity on ECM communities, i.e., phylogenetically related pines shared similar ECM fungal communities. Instead, ECM fungal community composition was strongly influenced by site-specific abiotic factors and dispersal. These findings reinforce the idea that taxonomic relatedness might be a factor promoting ECM colonization in exotic pines but that shifts in ECM communities may also be context-dependent. [ABSTRACT FROM AUTHOR]

Exotic pine trees are often introduced to novel places worldwide. How exotic pines interact with local microbial communities, such as symbiotic ectomycorrhizal (ECM) fungi, during early establishment compared to interactions by their native counterparts remains to be examined in detail. In this study, native masson pine (Pinus massoniana) and exotic slash pine (Pinus elliottii) seedlings were grown in field-collected soil cores. ECM root tips were collected 3- and 6-months after planting and fungi were identified using high-throughput sequencing. We found that host identity was a key factor determining ECM fungal community assembly after 3-months: native pines associated with Rhizopogon while exotic pines associated primarily with ECM generalists. After 6-months growth, however, ECM fungal communities in native and exotic pines were both dominated by Rhizopogon species. We also found that host selections of several pioneer ECM fungi shared by both native and exotic pines may facilitate an exotic pine's establishment. These findings indicate that more attention should be paid to ECM fungal community shuffling by exotic trees during early establishment and, in turn, the influence of the potential changes in ECM fungal communities on local forest ecosystems. • The recruited ECM community in pine seedlings was determined by host identity. • Spore-based Rhizopogon spp. were well adapted by both native and exotic pines. • Mesocosm method provides high percentage (>70%) of ECM fungi recovery. [ABSTRACT FROM AUTHOR]