Basidiomycete Species Research Articles

Antifungal activity of Wickerhamomyces silvicola

Wickerhamomyces silvicola strain Y-178 was shown to secrete a mycocin with a fungicidal effect. It exhibits the highest activity at pH 4.5 and elevated ambient osmotic pressure. Over 140 species belonging to 45 genera of ascomycetous yeasts were sensitive to the mycocin, while basidiomycetous species were resistant. Taxonomically homogenous species usually exhibit a homogenous response to mycocins.

Dynamics of the worldwide number of fungi with emphasis on fungal diversity in China

A survey and analysis of fungal taxa introduced over seven decades is presented. The numbers of introduced taxa were collated from ten editions of the Dictionary of the Fungi as well as from the Index of Fungi. In total, around 9100 genera and 108,000 species had been introduced by 2014. Between 1943 and 2008, the average numbers of introduced novel genera increased annually by 73 and species by 950. However, between 2008 and 2012, the average numbers of introduced novel genera increased annually by 110 and species by 1430. There were 1203 novel genera and 16,912 novel species described between 2001 and 2012, with an average of 100 new genera and 1397 new species published annually during the period. Advances in molecular techniques have accelerated the discovery of novel taxa; it therefore seems likely that many more novel taxa will be described in the future. Between 2001 and 2012, 1529 novel species were described from China, accounting for 9.2 % of all novel species descriptions worldwide. Around 17,000 fungal species had been recorded in China by 2014 with 5700 basidiomycete species, and 6700 species from important fungal groups being documented in Flora Fungorum Sinicorum with detailed descriptions, microscopic drawings and lists of voucher collections. An overview of studies on fungal diversity in China is presented.

Taxonomic studies in <I>Chrysoderma</I>, <I>Corneromyces</I>, <I>Dendrophysellum</I>, <I>Hyphoradulum</I>, and <I>Mycobonia</I>

Eight poorly known or unusual crustose and pileate basidiomycete species were studied. These included the type specimens of three monotypic genera: Chrysoderma alboluteum from Reunion is conspecific with Cerocorticium molle; Dendrophysellum amurense from the Russian Far East is a species of Vararia; and Hyphoradulum conspicuum belongs in Pseudolagarobasidium and is the first representative of the genus from Europe. Corticium murrillii, from Mexico, is congeneric with Corneromyces kinabalui. New combinations Vararia amurensis, Pseudolagarobasidium conspicuum, and Corneromyces murrillii are proposed. Mycobonia flava and M. brunneoleuca are macroscopically similar species with diagnostically distinct basidiospore shape and size. Mycobonia disciformis is accepted in Mycothele, and Mycobonia winkleri represents a species of unknown affinities. Recent molecular phylogenetic studies indicate that Mycobonia is embedded in Polyporus sensu stricto and is a synonym of Polyporus. Transferring M. brunneoleuca and M. flava to Polyporus requires the creation of the replacement names, P. polyacanthophorus and P. epitheloides.

Recombinant expression of four oxidoreductases in Phanerochaete chrysosporium improves degradation of phenolic and non-phenolic substrates

Phanerochaete chrysosporium belongs to a group of lignin-degrading fungi that secretes various oxidoreductive enzymes, including lignin peroxidase (LiP) and manganese peroxidase (MnP). Previously, we demonstrated that the heterologous expression of a versatile peroxidase (VP) in P. chrysosporium recombinant strains is possible. However, the production of laccases (Lac) in this fungus has not been completely demonstrated and remains controversial. In order to investigate if the co-expression of Lac and VP in P. chrysosporium would improve the degradation of phenolic and non-phenolic substrates, we tested the constitutive co-expression of the lacIIIb gene from Trametes versicolor and the vpl2 gene from Pleurotus eryngii, and also the endogenous genes mnp1 and lipH8 by shock wave mediated transformation. The co-overexpression of peroxidases and laccases was improved up to five-fold as compared with wild type species. Transformant strains showed a broad spectrum in phenolic/non-phenolic biotransformation and a high percentage in synthetic dye decolorization in comparison with the parental strain. Our results show that the four enzymes can be constitutively expressed in a single transformant of P. chrysosporium in minimal medium. These data offer new possibilities for an easy and efficient co-expression of laccases and peroxidases in suitable basidiomycete species.

Steroid hydroxylation by basidiomycete peroxygenases: a combined experimental and computational study.

The goal of this study is the selective oxyfunctionalization of steroids under mild and environmentally friendly conditions using fungal enzymes. With this purpose, peroxygenases from three basidiomycete species were tested for the hydroxylation of a variety of steroidal compounds, using H2O2 as the only cosubstrate. Two of them are wild-type enzymes from Agrocybe aegerita and Marasmius rotula, and the third one is a recombinant enzyme from Coprinopsis cinerea. The enzymatic reactions on free and esterified sterols, steroid hydrocarbons, and ketones were monitored by gas chromatography, and the products were identified by mass spectrometry. Hydroxylation at the side chain over the steroidal rings was preferred, with the 25-hydroxyderivatives predominating. Interestingly, antiviral and other biological activities of 25-hydroxycholesterol have been reported recently (M. Blanc et al., Immunity 38:106-118, 2013, http://dx.doi.org/10.1016/j.immuni.2012.11.004). However, hydroxylation in the ring moiety and terminal hydroxylation at the side chain also was observed in some steroids, the former favored by the absence of oxygenated groups at C-3 and by the presence of conjugated double bonds in the rings. To understand the yield and selectivity differences between the different steroids, a computational study was performed using Protein Energy Landscape Exploration (PELE) software for dynamic ligand diffusion. These simulations showed that the active-site geometry and hydrophobicity favors the entrance of the steroid side chain, while the entrance of the ring is energetically penalized. Also, a direct correlation between the conversion rate and the side chain entrance ratio could be established that explains the various reaction yields observed.

Hannaella phyllophila sp. nov., a basidiomycetous yeast species associated with plants in Thailand and Taiwan.

Five strains representing one novel anamorphic yeast species were isolated from plant leaves collected in Thailand (strains DMKU-SP186(T), ST-111 and ST-201) and Taiwan (strains FN20L02 and SM13L16). On the basis of morphological, biochemical, physiological and chemotaxonomic characteristics and sequence analysis of the D1/D2 region of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) region, they were assigned to a single novel species of the genus Hannaella. The sequences of the D1/D2 regions of the LSU rRNA genes of four of the strains (DMKU-SP186(T), ST-111, FN20L02 and SM13L16) were identical, while differing from strain ST-201 by 2 substitutions and 2 gaps. The nucleotide sequence of the ITS regions of the five strains differed from each other by between 0 and 3 nucleotide substitutions. The novel species was most closely related to Hannaella luteola, but showed 1.0-1.3% nucleotide substitutions (between 6 substitutions out of 568-606 nt and 8 substitutions, and 2 gaps out of 597 nt) in the D1/D2 region of the LSU rRNA gene and 1.4-2.0% nucleotide substitutions (6-9 substitutions out of 435 nt) in the ITS region. Ballistospores were produced by three of the strains on cornmeal agar at 15 and 20 °C after 4 weeks, while H. luteola did not produce ballistospores. The name Hannaella phyllophila sp. nov. is proposed. The type strain is DMKU-SP186(T) ( = BCC 69500(T) = NBRC 110428(T) = CBS 13921(T)).

Armillaria novae‐zelandiae and other basidiomycete wood decay fungi in New Zealand Pinus radiata thinning stumps

SummaryTwo studies were undertaken in a young New Zealand Pinus radiata stand to find a biological control agent for armillaria root disease caused by Armillaria novae‐zelandiae. Fresh thinning stumps were inoculated with saprophytic basidiomycete species as wooden dowel cultures or as homogenized aqueous mycelial suspensions, while all stumps were also inoculated with dowel cultures of A. novae‐zelandiae. After a period of between one and two years, no differences were found among test fungi in the percentage of Armillaria species isolated from stumps. However, inoculation of Stereum sanguinolentum as homogenate, and of Phlebiopsis gigantea, Sistotrema brinkmannii, Hypholoma acutum and Rigidoporus concrescens as dowel cultures, significantly increased their isolation incidence in comparison with stumps not treated by these species. Phlebiopsis gigantea, Resinicium bicolor and R. concrescens were also isolated with greater frequency nearer to their dowel inoculation points. Results suggest that P. gigantea and S. sanguinolentum should be included in further testing. However, a future trial is likely to be more effective if evaluation is directed towards the portion of the stump below the soil surface, particularly the root system.

Hannaella siamensis sp. nov. and Hannaella phetchabunensis sp. nov., two new anamorphic basidiomycetous yeast species isolated from plants.

Eight strains, representing two novel anamorphic yeast species, consisted of five strains isolated from the external surfaces of rice leaves (DMKU-RP72(T), DMKU-RP109, DMKU-RP119, YE-124 and YE-156) and one from a corn leaf (DMKU-CP430(T))4 collected in Thailand, and one strain isolated from each of a composite flower (11-1114) and a fallen dead leaf (12-301); the latter two were collected in Belize. On the basis of sequence analysis of the D1/D2 region of the large subunit rRNA gene and the internal transcribed spacer (ITS) region, they were suggested to be two novel species of the genus Hannaella. Seven strains (DMKU-RP72(T), DMKU-RP109, DMKU-RP119, YE-124, YE-156, 11-1114 and 12-301) differed from each other by 0-3 nt substitutions in the D1/D2 region and by 0-1 nt substitutions in the ITS region. In terms of pairwise sequence similarities of the D1/D2 region these seven strains were closest to Hannaella zeae, but with 1.2-1.7% (7-9) nucleotide substitutions. The sequences of the ITS region of these seven strains differed from H. zeae by 3.7-3.9% (16-17) nucleotide substitutions. Therefore, they were assigned to a single novel species and the name Hannaella siamensis sp. nov. has been proposed. The type strain is DMKU-RP72(T) ( = BCC 69493(T) = NBRC 110425(T) = CBS 13533(T)). Strain DMKU-CP430(T) represents the second novel species and was also most closely related to H. zeae, but with 1.0% (6) nucleotide substitutions in the D1/D2 region and 3.2% (14) nucleotide substitutions in the ITS region. It was assigned to the proposed novel species, Hannaella phetchabunensis sp. nov. (type strain DMKU-CP430(T) = BCC 69492(T) = NBRC 110424(T) = CBS 13386(T)).

English

Higher fungi are a major source of bioactive secondary metabolites, and researchers have established the existence of biochemical pathways solely for the purpose of producing mycotoxins and other natural products in fungi through the study of ecological chemical interactions.1 Recently, wood-degrading fungi received great attention for its possible use as antimicrobial agent. Schizophyllum commune, a species of basidiomycetes belonging to the Schizophyllaceae of Agaricales, played an important ecological role in degrading woody forest litter. This filamentously growing fungus secreted a neutral homoglucan that consists of a backbone chain of 1,3-β-D-glucopyranoses units linked with single 1,6-bonded β-D-glucopyranoses at about every third glucose molecule in the basic chain, called “Schizophyllan”.2 This polysaccharide has attracted attention in recent years in the pharmaceutical industry as an immunomodulatory, antineoplastic, and anti-viral agent with activities higher than other glucans. In addition, it is also applied in enhanced oil recovery, and cosmetics.3 Based on literature review, flavonoids are ubiquitous in photosynthesizing cells and could exert antifungal activity to inhibit the growth or spore germination.4 For example, Quercetin (3,3’,4’,5,7-pen tahydroxy flavone) is one of the most common native flavonoids occurring mainly in glycoside forms such as rutin (5,7,3’,4’-OH, 3-rutinose).5 Previous study done by Teoh et al.6 revealed that 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl(DDMP) belonged to the flavonoid fraction, and it was found to provide antifungal activities towards selected wood-degrading fungi of rubberwood. This unique sugar residue allowed saponins to scavenge superoxides by forming hydroperoxide intermediates, thus preventing biomolecular damage by free radicals.7 Bubble column bioreactor is a promising device for gas-liquid mass transfer and was being considered in biochemical application, especially for fermentation process.8 It also provides a number of advantages in both design and operation, such as high heat and mass transfer rates, compactness and low operating and maintenance costs. Furthermore, there is no mechanical agitation, and the air bubbles forced through the air compressor were responsible for the induced turbulent liquid mixing and the acMycelia Growth and Production of Total Flavonoids and 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methylby Schizophyllum commune Using a Bubble Column Bioreactor Considering Aeration Effect and Mass Transfer Study

Flora, mycota and vegetation of Dupkata Reserve (Rodopi Mts, Bulgaria)

The study represents a pilot scientific research of flora, mycota and vegetation within the Dupkata Reserve. Twenty three species, referred to 2 divisions, 3 classes and 16 families are recorded for the bryoflora. One of them is listed in the Habitat Directive. The vascular flora is presented by 103 species from 38 families. Forty eight vascular plants are considered as medicinal plants. Forty two species of larger ascomycetes and basidiomycetes are found in the reserve. Three of them are of high conservation value. The vegetation cover is consisted mostly of floristically poor communities of Spruce forest and mixed Spruce and Scots pine forests. Habitats within the reserve are presented by six types according to the Habitat Directive classification.

Potential Pathogens among Fungi Identified as Nonsporulating Molds from Blood Cultures

Twenty-eight molds were isolated from clinical blood cultures and were unidentifiable by cellular morphology using conventional microscopy. Using the utility of amplification and direct sequencing of internal transcribed spacer region of ribosomal RNA gene, 93% of these fungi were identified. Seventy-one percents of the molds were found to be associated with plants or soil with no or few published cases of human disease. These include species of basidiomycetes and ascomycetes such as Botryosphaeria dothidea, Phomopsis flavodonflavus, Inonotus pachyphloeus, Earlilella scabrosa, Calocybe indica, Athelia pellicularis, Tinctoporellus epimiltinus, Trametes lactinea, Coprinellus aureogranulat and Xylaria feejeensis. Some of the nonsporulating molds were identified as pathogen or potential pathogens in immunocompetent or immunocompromised hosts. These include Schizophylum commune and hyphomycetes such as Cladosporium cladosporoides, Aspergillus niger and Fusarium equiseti. Basidiomycetes and hyphomycetes identified in the current study are ubiquitous in the environment and are almost similar to the species of molds reported from cutaneous and respiratory samples suggesting that the fungi may represent contaminants rather than true fangaemia. Results of this study emphasize the need of an effort to minimise blood culture contamination and support the recommendation to incorporate clinical, radiologic findings and positive blood culture for molds in the diagnosis and management of invasive mycosis.

Yeast biogeography and the effects of species recognition approaches: the case study of widespread basidiomycetous species from birch forests in Russia.

Understanding diversity and distribution patterns of fungi, including yeasts, ultimately depends on accuracy of species recognition. However, different approaches to yeast species recognition often result in different entities or operational taxonomic units. We studied the effects of using different yeast species recognition approaches, namely morphological species recognition (MSR) and phylogenetic species recognition (PSR), on the distribution patterns of widespread basidiomycetous yeasts. Hence, we have revised a collection of yeast fungi isolated from spatially remote birch forests in the Moscow Region and Western Siberia with molecular typing and identification tools. PCR fingerprinting and rDNA sequencing analyses of strains of nine species previously identified on the basis of morphological and physiological tests (MSR) yielded 21 phylogenetic species (PSR), including three currently undescribed taxa. The number of distinct phylogenetic species comprised within a single morphospecies ranged from one to seven. A total of ten species were found in both regions, whereas the distribution of 11 yeasts was restricted to a single region only. Both geographical region and type of substrate (plant or soil) influence yeast distribution. Cryptococcus wieringae, C. victoriae, C. magnus, and Leucosporidium scottii were frequently found on plant substrates, whereas C. terricola and C. podzolicus were associated to soil substrates. Occurrence of C. magnus, C. albidus and Sporobolomyces roseus was found to depend on the geographical region. Microsatellite-PCR fingerprinting, MSP-PCR, applied to studying yeast intraspecific variability revealed three different types of distribution: (a) variability that depends on geographical factors (Curvibasidium cygneicollum, C. podzolicus, C. victoriae), (b) genetic identity irrespectively of the region of isolation (Rhodotorula pinicola, C. terricola), and (c) high degree of genetic variability that did not correlate with region of sampling (C. albidus and C. magnus).

The diversity and extracellular enzymatic activities of yeasts isolated from water tanks of Vriesea minarum, an endangered bromeliad species in Brazil, and the description of Occultifur brasiliensis f.a., sp. nov.

The diversity of yeast species collected from the bromeliad tanks of Vriesea minarum, an endangered bromeliad species, and their ability to produce extracellular enzymes were studied. Water samples were collected from 30 tanks of bromeliads living in a rupestrian field site located at Serrada Piedade, Minas Gerais state, Brazil, during both the dry and rainy seasons. Thirty-six species were isolated, representing 22 basidiomycetous and 14 ascomycetous species. Occultifur sp., Cryptococcus podzolicus and Cryptococcus sp. 1 were the prevalent basidiomycetous species. The yeast-like fungus from the order Myriangiales, Candida silvae and Aureobasidium pullulans were the most frequent ascomycetous species. The diversity of the yeast communities obtained between seasons was not significantly different, but the yeast composition per bromeliad was different between seasons. These results suggest that there is significant spatial heterogeneity in the composition of populations of the yeast communities within bromeliad tanks, independent of the season. Among the 352 yeast isolates tested, 282 showed at least one enzymatic activity. Protease activity was the most widely expressed extracellular enzymatic activity, followed by xylanase, amylase, pectinase and cellulase activities. These enzymes may increase the carbon and nitrogen availability for the microbial food web in the bromeliad tank of V. minarum. Sequence analyses revealed the existence of 10 new species, indicating that bromeliad tanks are important sources of new yeasts. The novel species Occultifur brasiliensis, f.a., sp. nov., is proposed to accommodate the most frequently isolated yeast associated with V. minarum. The type strain of O. brasiliensis, f.a., sp. nov. is UFMG-CM-Y375(T) (= CBS 12687(T)). The Mycobank number is MB 809816.

Species‐specific PCR for rapid identification of Ganoderma philippii and Ganoderma mastoporum from Acacia mangium and Eucalyptus pellita plantations in Indonesia

SummaryDNA sequence variation in the rDNA internal transcribed spacers (ITS) was exploited to design species‐specific primers for Ganoderma philippii and Ganoderma mastoporum, two fungi associated with red root rot in Acacia mangium and other perennial crops. Specificity was verified against five other Ganoderma species, 34 other basidiomycete species and two ascomycete species. The PCR tests assisted in the identification of 822 fungal isolates obtained from A. mangium and Eucalyptus pellita plantations in Indonesia. These tests have provided a high level of confidence in the identification of the major root rot pathogens, information that can be used to support the development of management options for their control in A. mangium plantations.

Macrofungi in community managed forest, Rupandehi district, Nepal: An ethnomycological study

This investigation explores the macrofungi with their identification and documentation of indigenous knowledge. The study area occupies 633 hector and lies within a narrow limit of altitude between 225 and 265msl. The collected samples represented 31 species of Basidiomycetes belonging to 7 orders, 17 families and 22 genera. The dried specimens are deposited in the Tribhuvan University Central Department of Botany, Pathology Unit, Kathmandu, Nepal. The area embraces many mycophagous ethnic groups. The mycoelements prevailing in this area need sustainable development.

Plant-polysaccharide-degrading enzymes from Basidiomycetes.

Basidiomycete fungi subsist on various types of plant material in diverse environments, from living and dead trees and forest litter to crops and grasses and to decaying plant matter in soils. Due to the variation in their natural carbon sources, basidiomycetes have highly varied plant-polysaccharide-degrading capabilities. This topic is not as well studied for basidiomycetes as for ascomycete fungi, which are the main sources of knowledge on fungal plant polysaccharide degradation. Research on plant-biomass-decaying fungi has focused on isolating enzymes for current and future applications, such as for the production of fuels, the food industry, and waste treatment. More recently, genomic studies of basidiomycete fungi have provided a profound view of the plant-biomass-degrading potential of wood-rotting, litter-decomposing, plant-pathogenic, and ectomycorrhizal (ECM) basidiomycetes. This review summarizes the current knowledge on plant polysaccharide depolymerization by basidiomycete species from diverse habitats. In addition, these data are compared to those for the most broadly studied ascomycete genus, Aspergillus, to provide insight into specific features of basidiomycetes with respect to plant polysaccharide degradation.

Materials to knowledage of the geographical distribution of higher fungi in Europe. IV

The localities of 24 species of Basidiomycetes, recorded from Poland, are presented and their distribution shown by the measuring point method with occasional reference to the geographical range of several trees.

Insights into the effects of serpentine soil conditions on the community composition of fungal symbionts in the roots of Onosma echioides

In this study, we investigated the impact of the extreme edaphic conditions of serpentine soils on the community structure of fungal symbionts in the roots of the perennial herb Onosma echioides (Boraginaceae). Sixteen root systems of O. echioides were obtained from two serpentine and two non-serpentine sites in the region of Tuscany (Italy) and the associated fungal communities were characterized by 454 pyrosequencing of fungal internal transcribed spacer 1 (ITS1) amplicon libraries. Clustering analysis of 173,639 sequence reads yielded a total of 699 non-singleton operational taxonomic units (OTUs), with the number of non-singleton OTUs per fungal community varying between 65 and 225. The richness of the fungal communities did not appear to be affected by the edaphic conditions of serpentine soils but the compositions of the serpentine and non-serpentine communities differed significantly, even though community structures were mainly influenced by strong spatial effects at low-to-medium distance scales. Whereas non-serpentine communities were dominated, at least in terms of sequence read abundance, by OTUs assigned to the genera Rhizophagus and Glomus (Glomeromycota), serpentine communities were dominated by OTUs assigned to the genera Ceratobasidium and Coprinellus (Basidiomycota). The functional roles of these basidiomycetous species in the roots of serpentine O. echioides specimens are, however, unclear and although their presence may affect the serpentine tolerance of the host plant, they may also be opportunistic symbionts that benefited from the reduced abundance of arbuscular mycorrhizal fungi to colonize the roots of O. echioides in serpentine environments.

Two yeast species Cystobasidium psychroaquaticum f.a. sp. nov. and Cystobasidium rietchieii f.a. sp. nov. isolated from natural environments, and the transfer of Rhodotorula minuta clade members to the genus Cystobasidium.

Many species of dimorphic basidiomycetes are known only in their asexual phase and typically those pigmented in different hues of red have been classified in the large polyphyletic genus Rhodotorula. These yeasts are ubiquitous and include a few species of some clinical relevance. The phylogenetic distribution of Rhodotorula spans three classes: Microbotryomycetes, Cystobasidiomycetes and Exobasidiomycetes. Here, the presented multi-gene analyses resolved phylogenetic relationships between the second largest group of Rhodotorula and the mycoparasite Cystobasidium fimetarium (Cystobasidiales, Cystobasidiomycetes, Pucciniomycotina). Based on the results, we propose the transfer of nine species belonging to the Rhodotorula minuta clade into the genus Cystobasidium. As a result, the clinically relevant species R. minuta will be renamed Cystobasidium minutum. This proposal follows ongoing reassessments of the anamorphic genus Rhodotorula reducing the polyphyly of this genus. The delimitation of the R. minuta clade from Rhodotorula species comprised in Sporidiobolales including the type species Rhodotorula glutinis is an important step to overcome obsolete generic placements of asexual basidiomycetous yeasts. Our proposal will also help to distinguish most common red yeasts from clinical samples such as members of Sporidiobolales and Cystobasidiales. The diagnosis of the genus Cystobasidium is amended by including additional characteristics known for the related group of species. The taxonomic change enables us to classify two novel species with the phylogenetically related members of the R. minuta clade in Cystobasidium. The recently from natural environments isolated species are described here as Cystobasidium psychroaquaticum f.a. sp. nov. (K-833(T)=KBP 3881(T)=VKPM Y-3653(T)=CBS11769(T)=MUCL 52875(T)=DSM 27713(T)) and Cystobasidium rietchiei f.a. sp. nov. (K-780(T)=KBP 4220(T)=VKPM Y-3658(T)=CBS12324(T)=MUCL 53589(T)=DSM 27155(T)). The new species were registered in MycoBank under MB 809336 and MB 809337, respectively.

The diversity of yeasts associated with grapes and musts of the Strekov winegrowing region, Slovakia.

Many different yeast species have been isolated from grapes and musts worldwide. The diversity and frequency of yeasts depend on a number of factors such as the grape variety, the physical damage of the grapes, the weather conditions and the chemical composition of must. A total of 366 isolates were associated with the three grape cultivars: Blue Frankish, Green Veltliner and Sauvignon blanc over four consecutive years. Yeast cultures were isolated from the grapes and from the fermenting musts after the first and seventh days. The ascomycetous yeasts of the genera Aureobasidium, Candida, Hanseniaspora, Metschnikowia, Pichia, Saccharomyces and Saccharomycopsis together with basidiomycetous yeasts of the genera Cryptococcus, Dioszegia, Filobasidium, Rhodotorula and Sporidiobolus were associated with the three grape varieties. Hanseniaspora uvarum, Metschnikowia pulcherrima, Pichia kluyveri, Pichia kudriavzevii and Sporidiobolus pararoseus were found on the berries in significant amounts. P. kluyveri and P. kudriavzevii were more associated with the damaged grapes, whereas Sp. pararoseus with intact ones. H. uvarum and M. pulcherrima were present on both types of grapes almost equally. The yeast composition and quantitative representation of yeast species varied over the grape varieties and the years examined. Although the basidiomycetous species formed a significant proportion of the yeast population in some individual grape variety/year combinations, the ascomycetous species were dominant.