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Many species of fungi have been detected in the healthy human gut; however, nearly half of all taxa reported have only been found in one sample or one study. Fungi capable of growing in and colonizing the gut are limited to a small number of species, mostlyCandidayeasts and yeasts in the family Dipodascaceae (Galactomyces, Geotrichum, Saprochaete).Malasseziaand the filamentous fungusCladosporiumare potential colonizers; more work is needed to clarify their role. Other commonly-detected fungi come from the diet or environment but either cannot or do not colonize (PenicilliumandDebaryomycesspecies, which are common on fermented foods but cannot grow at human body temperature), while still others have dietary or environmental sources (Saccharomyces cerevisiae, a fermentation agent and sometime probiotic;Aspergillusspecies, ubiquitous molds) yet are likely to impact gut ecology. The gut mycobiome appears less stable than the bacterial microbiome, and is likely subject to environmental factors. [ABSTRACT FROM PUBLISHER]

We have entered the Age of the Microbiome, with new studies appearing constantly and whole journals devoted to the human microbiome. While bacteria outnumber other gut microbes by orders of magnitude, eukaryotes are consistently found in the human gut and are represented primarily by the fungi. Compiling 36 studies 1917-2015 we found at least 267 distinct fungal taxa have been reported from the human gut, and seemingly every new study includes one or more fungi not previously described from this niche. This diversity, while impressive, is illusory. If we examine gut fungi, we will quickly observe a division between a small number of commonly detected species (Candida yeasts, Saccharomyces and yeasts in the Dipodascaceae, and Malassezia species) and a long tail of taxa that have been reported only once. Furthermore, an investigation into the ecology of these rare species reveals that many of them are incapable of colonization or long-term persistence in the gut. This paper examines what we know and have yet to learn about the fungal component of the gut microbiome, or "mycobiome", and an overview of methods. We address the potential of the field while introducing some caveats and argue for the necessity of including mycologists in mycobiome studies. [ABSTRACT FROM AUTHOR]

The systematic position of secotioid (Torrendia) and gasteroid (Amarrendia) forms within the agaricoid Amanita lineage (Agaricales, Basidiomycota) was studied with molecular (nLSU, ITS) data. Secotioid and gasteroid forms occur in fore" independent clades nested within agaricoid forms. One clade corresponds to the secotioid T. pulchella from southern Europe and northern Africa. The others correspond to Torrendia and Amarrendia species from Australia. Mediterranean climatic conditions are postulated as a force driving the convergent evolution of these secotioid and at least one of the gasteroid forms in geographically distant areas. Species formerly placed in Torrendia and Amarrendia are transferred to Amanita. A new species of Torrrendia from Australia was discovered during the revision of the collections originally identified as T. arenaria and is described here as Amanita pseudoinculta. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) and the associated mycotoxin deoxynivalenol (DON) negatively impact the wheat industry worldwide. In North America, FHB is mainly caused by Fusarium graminearum sensu stricto. The purpose of this study was to evaluate, under storage conditions, the expression of the DON biosynthetic gene trichodiene synthase (Tri5) of F. graminearum in grain of hard red winter wheat cultivars 'Overley' (FHB-susceptible) and 'Overland' (moderately resistant to FHB) from field plots treated or untreated with the triazole fungicide Prosaro and the strobilurin fungicide Headline. Infected grain was stored and periodically sampled to determine gene expression by qRT-PCR analysis. The F. graminearum housekeeping gene GAPDH was consistently detected, indicative of metabolically active fungi, and Tri5 detection was significantly higher in 'Overley' compared with 'Overland'. Tri5 gene expression and DON concentrations showed little to no correlation; consequently, Tri5 expression levels did not accurately predict DON concentrations. The strobilurin did not significantly reduce Tri5 gene expression compared with untreated wheat. In the triazole treatment, a significant reduction in the relative expression of Tri5 was detected after 120 days, as well as a downregulation of Tri5 from 60 to 120 days of storage in 'Overley'. In grain from strobilurin-treated plots of both cultivars, the expression of Tri5 increased from 0 to 30 days after tempering. Genetic expression of Tri5 that is necessary for the production of DON can increase during storage of high-moisture grain. Fusarium fungi can persist in wheat kernels for several months postharvest and may actively produce toxin during this period. [ABSTRACT FROM AUTHOR]

Several Fusarium species cause Fusarium head blight (FHB), a devastating disease that affects wheat and other small grain cereals. Besides causing significant yield losses, FHB pathogens reduce the quality of the grain and may produce mycotoxins that are harmful to both humans and animals. The development of effective management strategies for this disease requires an understanding of the composition of the FHB pathogen populations, which is important because different populations could be affected selectively. Recent reports of shifts in populations of FHB pathogens have shown that these populations are dynamic and change continuously, often associated with increased yield losses or changes in the mycotoxins produced in the grain. These population shifts include: replacement of F. graminearum by F. poae in Italy, hypothesized to be due to variation in environmental conditions; replacement of F. culmorum by F. graminearum in Europe, associated with climate change and increased maize production; a more aggressive and toxigenic F. asiaticum 3-ADON population replacing the existing NIV population in China; and a highly toxigenic population composed mainly of F. graminearum 3-ADON isolates replacing the existing 15-ADON population in North America. Additionally, reports of recent introductions of foreign species or populations into new areas include: F. asiaticum outside of Asia, F. graminearum NIV isolates in the USA and Luxembourg, F. graminearum 15-ADON isolates in Norway, F. graminearum in South Korea, F. boothii in Europe and USA, F. vorosii in Hungary and F. cortaderiae in New Zealand and Europe. [ABSTRACT FROM AUTHOR]