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Leaf blight and defoliation caused by Teratosphaeria species is one of the most important leaf diseases of Eucalyptus globulus. Due to the importance of this tree species for the production of pulp and paper, and recent reports of severe leaf disease symptoms in Brazil, the present study was conducted to identify the pathogen(s) involved. Symptomatic leaves were collected in the Brazilian states of Paraná and Rio Grande do Sul, single ascospore cultures established, and isolates were investigated using DNA-based molecular tools. A species-specific PCR and sequence data from the nuclear ribosomal DNA operon were used for species identification. The following seven species were identified: Mycosphaerella scytalidii, Dissoconium dekkeri (=M. lateralis), Teratosphaeria ohnowa, T. perpendicularis, T. pseudafricana, T. flexuosa and T.nubilosa. Of the recorded species, T. nubilosa is regarded as the most serious threat to the cultivation of E. globulus in the states surveyed. [ABSTRACT FROM AUTHOR]

The ascomycetous genus Scirrhia is presently treated as a member of Dothideomycetidae, though uncertainty remains as to which family it belongs in Capnodiales, Ascomycota. Recent collections on stems of a fern, Pteridium aquilinum (Dennstaedtiaceae) in Brazil, led to the discovery of a new species of Scirrhia, described here as S. brasiliensis. Based on DNA sequence data of the nuclear ribosomal DNA (LSU), Scirrhia is revealed to represent a member of Dothideomycetes, Capnodiales, Mycosphaerellaceae. Scirrhia is the first confirmed genus in Mycosphaerellaceae to have well developed pseudoparaphyses and a prominent hypostroma in which ascomata are arranged in parallel rows. Given the extremely slow growth rate and difficulty in obtaining cultures of S. brasiliensis on various growth media, it appears that Scirrhia represents a genus of potentially obligate plant pathogens within Mycosphaerellaceae. [ABSTRACT FROM AUTHOR]

During studies of yeasts associated with soil in a Cerrado-Atlantic Rain Forest ecotone site in Brazil, three orange-pigmented yeast strains were isolated from samples collected in Minas Gerais state, Brazil. Molecular analyses combining the 26S rRNA gene (D1/D2 domains) and the internal transcribed spacer (ITS) sequences as well as whole-genome sequence data showed that these strains could not be ascribed to any known species in the basidiomycetous genus Phaffia , and thus they are considered to represent a novel species for which the name Phaffia brasiliana sp. nov. is proposed. The holotype is CBS 16121 T and the MycoBank number is MB 839315. The occurrence of P. brasiliana in a tropical region is unique for the genus, since all other species occur in temperate regions. Two factors appear to contribute to the distribution of the novel taxon: first, the region where it was found has relatively moderate temperature ranges and, second, an adaptation to grow or withstand temperatures higher than those of the other species in the genus seems to be in place.

During studies of the yeast diversity associated with rotting wood in Brazil and fruits, plants and insects in French Guiana, three strains of a new species were isolated. Analysis of the sequences of the internal transcribed spacer (ITS)-5.8S and D1/D2 domains of the large subunit of the rRNA gene showed that this species belongs to the genus Hyphopichia and its closest relative is Candida homilentoma. These species differ by 44 nucleotide substitutions in D1/D2 sequences. A new species Hyphopichia buzzinii f. a., sp. nov., is proposed to accommodate these isolates. The type strain of Hyphopichia buzzinii sp. nov. is CLIB 1739 T (=CBS 14300 T  = UFMG-CM-Y6121 T ; MycoBank number is MB 815609). In addition, we isolated 11 strains of C. homilentoma from rotting wood, leaf surfaces, and water bodies in Brazil, and these strains when crossed among one another and with the type strain (CBS 6312 T ) of this species, produced hat-shaped ascospores typical of the genus Hyphopichia. We describe the teleomorph of C. homilentoma as a new combination, Hyphopichia homilentoma comb. nov. (type strain CBS 6312 T ; MycoBank number is MB 820009). We also propose to transfer the other six Candida species of the Hyphopichia clade to this genus as new combinations. Hyphopichia homilentoma produced ethanol and xylitol from D-xylose whereas H. buzzinii was only able to convert this pentose to xylitol.