Penicillium hermansii, a new species causing smoky mould in white button mushroom production

Abstract

Competing fungi in white button mushroom (Agaricus bisporus, champignon) cultivation causes significant episodic losses. One of these competing fungi is known as Bsmoky mould^. It owes its name to the production of high numbers of spores after the disturbance of compost, which resembles smoke. We investigated strains isolated from smoky mould cases in the Netherlands, UK and Canada and show that these outbreaks were caused by a new Penicillium species, named P. hermansii sp. nov. (type strain CBS 124296 T). Several Penicillium species are reported to cause smoky mould. However, we so far have no indications that smoky mould is caused by other Penicillium species than P. hermansii. This species belongs to section Exilicaulis and differs from other Penicillia by its slow growth rate on Czapek yeast agar (CYA) and malt extract agar (MEA) and its inability to grow on CYA supplemented with 5% salt and CYA and MEA incubated at 37°C.

Classification of Aspergillus, Penicillium, Talaromyces and related genera (Eurotiales): An overview of families, genera, subgenera, sections, series and species

“…Sexual morph unknown (12 species) or present (six species) (see list of accepted species), eupenicillium-type, brown, orange-brown or pinkish brown; ascospores (broadly) ellipsoidal, with one or two pairs of longitudinal flanges, convex smooth, roughened or spinose. Series description based on Pitt, 1980 , Peterson et al., 1999 , Visagie et al., 2016c and Houbraken et al. (2019) .…”

Penicillium Amapaense sp. nov. Exilicaulis Section and New Records of Penicillium Labradorum in Brazil Isolated from Amazon River Sediments with Potential Applications in Agriculture and Biotechnology

“…Erubescentia evidenced the lower resolution achieved by the current recommended barcode, which, for most of branches, produced values lower than 80 and 0.95 for bootstrap and posterior probability from Bayesian inference, respectively (Visagie et al 2016). Recently, a phylogenetic tree of Penicillium species was also constructed with bootstrap values below 70 and posterior probability from Bayesian inference below 0.95, but still allow the characterization of P. hermansii as a new species (Houbraken et al 2019). Taken together, our results and the literature indicate the need to incorporate new loci, or even the development of new algorithms for a more accurate taxonomic analysis to better resolve the evolutionary relationships of fungal species (Choi & Kim 2017).…”

“…Penicillium hermansii, which is also a member of the ser. Erubescentia, has been reported to cause problems in mushroom cultivation (Houbraken et al 2019).…”

Penicillium gercinae and Penicillium stangiae (Eurotiomycetes, Ascomycota), two new species from soil in Brazil

“…DNA extraction was performed using the DNA Wizard Genomic DNA Purification Kit, following the manufacturer's recommendations. The β-tubulin (BenA), calmodulin (CaM), internal transcribed spacer (ITS), and RNA polymerase II second largest subunit (RPB2) gene regions were amplified using the primers Bt2a and Bt2b, CMD5 and CMD6, ITS1 and ITS4, and RPB2-5F and RPB2-7CR, respectively (Houbraken et al 2019), with PCR conditions as described by Visagie et al (2014). The PCR products were purified using the Exosap illustrative enzyme ExoProStar™ 1-Step (GE Healthcare Life Sciences, Little Chalfont, UK) and sequenced at the LABCEN/CCB sequencing platform at the UFPE (Recife, Brazil) using the same primers.…”