Testing a co-formulation of CO 2 -releasing material with an entomopathogenic fungus for the management of subterranean termite pests Abstract Termites cause significant damage to cocoa trees. Entomopathogenic fungi (EPFs) such as Metarhizium brunneum have been considered as a sustainable alternative to abusive use of insecticides against termites. However, potent EPF application is limited by its repellency effects, host avoidance, and termite defense mechanisms such as grooming among nest mates. Termites use CO2 to locate plant roots. This study investigated whether CO2-emitting capsules could attract termites. Capsules formulated without fungus (CEC) as well as those formulated with M. brunneum Cb15-III (CECEPF) were tested for attractiveness to termites with other attractive components using modified four-arm olfactometers. Worker termites’ infection by the fungus growing from the capsules as well as its horizontal transmission was assessed through the autodissemination approach. Significantly, more termites were attracted to CEC compared with other attractive components. Higher number of termites was attracted by CECEPF and cocoa seedlings than dry wood and yeast in a choice test. When termites were directly exposed to sporulating capsules, 100% mortality was obtained within 5 days. However, in the horizontal transmission experiment, no significant differences were observed as regards termites’ mortality in the treatment compared with the control groups. CECEPF did not cause any apparent repellency to termites as compared with CEC. This strategy offers high potential to promote biological termite control using CECEPF as alternative to insecticides. Further studies are warranted to evaluate the efficacy of these capsules under field conditions and explore their commercialization for termite management.

What is cultivated oyster mushroom? Phylogenetic and physiological study of Pleurotus ostreatus and related taxa Abstract The wild and cultivated isolates of Pleurotus ostreatus were the subject of a phylogenetic analysis, AMOVA of DNA sequences, exact test of population differentiation, estimation of evolutionary divergence, and cardinal temperature measurement. Two significantly genetically separated groups (OA and OB) with limited mutual gene flow were revealed. While OA is identical with P. ostreatus sensu stricto and includes mainly wild isolates, OB is a more genetically variable group of cultivated isolates of unclear geographical origin. The delimitation of the two groups is confirmed by three genetic markers (ITS, TEF1 and RPB2). Limited gene flow between those two groups was detected, but this is comparable to the putative gene flow between OA, OB on the one hand and P. eryngii and P. pulmonarius on the other. This gene flow between OA and OB may be caused by artificial breeding activities, but the number of such hybridisation events is limited. The genetic differences are also confirmed by the different growth rates of the two groups. The centre of distribution of P. ostreatus s. s. is in Eurasia, while the origin of the OB group is unknown. The availability of a validly published taxonomic name for OB is discussed.

Sugarcane glycoproteins control dynamics of cytoskeleton during teliospore germination of Sporisorium scitamineum Abstract Sporisorium scitamineum teliospores possess an organized cytoskeleton involved in important developmental and physiological processes. It has been described that microtubules appear to be fundamental for nucleus translocation during germination and hyphal growth, whereas actin polymerization is necessary for the formation of invaginations during teliospore displacement. Here, a global vision of the actin cytoskeleton organization throughout the life cycle of S. scitamineum cells is shown, providing evidence that a perfectly structured F-actin network is necessary to trigger smut pathogenicity. Moreover, although myosin presence in teliospores had been previously described, herein actin and myosin co-locations are demonstrated by confocal microscopy during both invaginations formation and germination. In turn, F-actin and microtubules (MTs) interact, jointly participating in the establishment of cell polarity. The resistant sugarcane cultivar Mayari 55-14 produces high molecular mass glycoproteins (HMMG) that differently affect F-actin organization at different stages of fungal development. HMMG first supported F-actin to induce the movement of teliospores towards the cytoagglutination points. At later stages of fungal development, HMMG disorganized F-actin which prevented the protrusion of germinative tube. A continuous exposure to HMMG provoked apoptosis in pathogenic, diploid cells and a delay in sporidia conjugation that could be crucial for plant resistance.

Resurrection of Paraisaria in the Ophiocordycipitaceae with three new species from Thailand Abstract Paraisaria is distinct from Ophiocordyceps and is resurrected as a valid genus within Ophiocordycipitaceae. Multi-gene phylogenetic analyses and morphological characterization support the split of Paraisaria from Ophiocordyceps. Three new species are named from Thailand including Paraisaria orthopterorum, P. phuwiangensis, and P. yodhathaii. New species combinations are made for Ophiocordyceps amazonica, O. blattarioides, O. coenomyiae, O. gracilioides, O. gracilis, O. heteropoda, O. paramyrmicarum (= Paraisaria myrmicarum), and O. tettigonia.

Three new hygrophilous species of Inocybe , subgenus Inocybe Abstract Inocybe is a cosmopolitan genus of gilled mushrooms with high species diversity in the northern hemisphere. Focusing on moist habitats in Central Europe, several collections could not be assigned to any known species of Inocybe. Phylogenetic analyses revealed that these collections belonged to three phylogenetically distinct lineages. To ensure a correct interpretation of the species identity in comparison with morphologically similar species, an isotype of I. flavobrunnescens, isoparatypes of I. hirculus and I. lacunarum, and a paratype of I. caprimulgi were examined both morphologically and phylogenetically. Sequencing of the lectotype of I. tabacina Furrer-Ziogas designated in this manuscript failed, but other collections unequivocally belonging to the same species could be included in molecular phylogenies. As a result of molecular phylogenetic and morphological analyses, three new hygrophilous species of the genus Inocybe, subgenus Inocybe, are described: one smooth-spored, I. botaurina, and two nodulose-spored, I. bombina and I. undinea.

New plectosphaerellaceous species from Dutch garden soil Abstract During 2017, the Westerdijk Fungal Biodiversity Institute (WI) and the Utrecht University Museum launched a Citizen Science project. Dutch school children collected soil samples from gardens at different localities in the Netherlands, and submitted them to the WI where they were analysed in order to find new fungal species. Around 3000 fungal isolates, including filamentous fungi and yeasts, were cultured, preserved and submitted for DNA sequencing. Through analysis of the ITS and LSU sequences from the obtained isolates, several plectosphaerellaceous fungi were identified for further study. Based on morphological characters and the combined analysis of the ITS and TEF1-α sequences, some isolates were found to represent new species in the genera Phialoparvum, i.e. Ph. maaspleinense and Ph. rietveltiae, and Plectosphaerella, i.e. Pl. hanneae and Pl. verschoorii, which are described and illustrated here.

Two new species of Clavulina and the first record of Clavulina reae from temperate Abies religiosa forests in central Mexico Abstract Clavulina is an ectomycorrhizal genus of macroscopic basidiomycetes, mostly with clavarioid basidiomata, distributed worldwide. The most commonly reported species are C. amethystina, C. cinerea, C. coralloides, and C. rugosa, which are part of a species complex in temperate ecosystems. In this work, we describe two new species, C. mahiscolorata and C. parvispora, from temperate forests of central Mexico. We also present a geographical range redistribution of C. reae, which displays great macromorphological variation regarding basidiome branching rank, colors, and tip shape. We provide macromorphological, micromorphological, and habitat data for each species, as well as nuclear rDNA ITS, rDNA LSU, and RPB2 sequences. Our findings highlight an underestimation of species richness in temperate ecosystems, as a consequence of assigning existing epithets to taxa without proper morphological and molecular analyses. The designation of neotypes for temperate species of Clavulina is urgent to delimit species concepts for the genus.

On Protomerulius and Heterochaetella (Auriculariales, Basidiomycota) Abstract The taxonomy of Protomerulius and Heterochaetella is revised based on DNA data and morphological evidence, and their type species, P. brasiliensis and H. dubia, are proved to be congeneric. As a consequence, H. dubia and related species, of which four are described as new, are placed in Protomerulius. Heterochaete microspora is also combined in Protomerulius, and the genus concept is redefined to encompass effused species with smooth or spiny hymenophore and monomitic hyphal structure. Psilochaete multifora, gen. and spec. nov. is a distant relative of Protomerulius spp. found in Norway. Heterochaetella cystidiophora is re-collected in Brazil and placed in the synonyms of Heterochaete sanctae-catharinae. This species does not belong to the Protomerulius–Heterochaetella lineage, and it is transferred to Metulochaete, gen. nov.

Relationships between endophytic and pathogenic strains of Inonotus (Basidiomycota) and Daldinia (Ascomycota) from urban trees Abstract The mycelia of wood-decay fungi can persist at a latent endophytic phase in living plant tissues and switch their trophic state under certain environmental conditions. Wood-decay models that take into account these organisms would improve predictability importance in urban environments. In this study, we evaluated the relationship between endophytic and pathogenic strains of Inonotus and Daldinia from urban London plane trees. In vitro wood-decay tests, oxidase reactions and phylogenetic analyses (ITS region, beta-tubulin and nLSU genes) were used to differentiate endophytic and wood-decay strains. All strains significantly reduced the weight of London Plane wood in vitro and had positive oxidase reactions. Endophytic and pathogenic strains of both genera were phylogenetically indistinguishable as evidenced by high sequence similarities, suggesting that endophytic strains can switch their trophic state and can cause wood decay. The capacity of endophytic fungi to switch from a quiescent to a degradative trophic state should be incorporated into predictive models of tree longevity. These revised models could help to predict the impact of wood decay in urban landscapes. Graphical abstract

Are Trechisporales ectomycorrhizal or non-mycorrhizal root endophytes? Abstract Trechispora (Hydnodontaceae) is considered as a soil-inhabiting fungus. However, some species in the genus are frequently forming basidiomes on soil, a typical feature of ectomycorrhizal fungi. Ectomycorrhizal basidiomes are found in neotropical and subtropical region, but taxonomical information and DNA sequences of root fungi and basidiomes from native Atlantic Rainforest are poorly reported. Basidiomes and soil samples including roots, humus layer, and mineral soil were collected in the Atlantic Rainforest, in Florianópolis (South of Brazil). Sequences of the ITS region were obtained from all sample types and subjected to phylogenetic reconstruction. Two sequences amplified from apparently ectomycorrhizal roots belonged to Trechispora and suggested a root-associated ecology, at least biotrophic and possibly ectomycorrhizal. The analysis of isotope abundance in the same Brazilian site and in French Guiana showed that Trechispora thelephora has high 15N abundance and is often intermediate between ectomycorrhizal and saprotrophic species in 13C abundance. This is congruent with a plant biotrophic ecology, perhaps ectomycorrhizal. Future investigations in subtropical regions are needed to determine whether such a mode of nutrition is widespread among Trechispora.