Sclerotinia sclerotiorum is responsible for the white mold of soybeans, and the difficulty to control the disease in Brazil is causing million-dollar damages. Stachybotrys levispora has shown ...activity against S. sclerotiorum. In our present investigation, we analyzed the chemical basis of this inhibition. Eight compounds were isolated, and using spectroscopic methods, we identified their structures as the known substances 7-dechlorogriseofulvin, 7-dechlorodehydrogriseofulvin, griseofulvin, dehydrogriseofulvin, 3,13-dihydroxy-5,9,11-trimethoxy-1-methylbenzophenone, griseophenone A, 13-hydroxy-3,5,9,11-tetramethoxy-1-methylbenzophenone, and 12-chloro-13-hydroxy-3,5,9,11-tetramethoxy-1-methylbenzophenone. Griseofulvin inhibited the mycelial growth of S. sclerotiorum at 2 μg mL–1. Thus, the antagonistic effect of S. levispora to S. sclerotiorum may well be due to the presence of griseofulvins. Our results stimulate new work on the biosynthesis of griseofulvins, to locate genes that encode key enzymes in these routes and use them to increase the production of these compounds and thus potentiate the fungicide effect of this fungus. S. levispora represents an agent for biocontrol, and griseofulvin represents a fungicide to S. sclerotiorum.
Ingoldian fungi are a dominant group in aquatic environments. However, they are poorly known and studied, especially in the tropics. To increase knowledge about their diversity and distribution, ...samples of foam and decaying submerged leaves were collected from 12 areas in Brazil across four biomes (Amazon, Atlantic Forest, Caatinga, and Cerrado). Slides were deposited in the HUEFS Herbarium. Thirty-five taxa were identified from foam and 24 from leaf spore suspension. These were distributed in five classes, mostly belonging to Ascomycota, with Leotiomycetes being the most representative class. Angulospora aquatica, Biflagellosporella amazonensis, Isthmotricladia laeensis and Lateriramulosa bi-inflata are new records for Brazil; Variocladium rangiferinum and Tricladium fuscum are new records for the Neotropics; and Polylobatispora deltoidea is a new record for the Americas. Description, illustration, and geographical distribution details are provided for the new records. The study showed a high richness of Ingoldian fungi and provides a basis for determining the biodiversity and ultimate conservation of the studied areas.
The biodiversity of filamentous fungi and their ecological relationships in the context of decaying
Araucaria angustifolia
(an endangered conifer) substrates are still mostly unknown. The present ...study aimed to investigate the diversity of saprotrophic filamentous fungi, based on morphological identification, associated with
A. angustifolia
, in addition to assessing possible saprobic/plant affinity relationship, and verifying whether the study areas and substrates affect the composition of the mycobiota. A total of 5000 substrates (decaying needles and twigs) were collected during five expeditions (2014/2015) to two areas: São Francisco de Paula National Forest (FLONA-SFP) and São Joaquim National Park (PARNA-SJ), Brazil. A total of 135 species distributed among 85 genera, 40 families, nine classes, 24 orders, three subphyla, and two phyla were identified. One new genus and five new species that were previously described, and six rare species and five species with affinity for
A. angustifolia
were also recorded. The twigs showed a community of fungi with greater richness and dominance. Conversely, the values of abundance, Simpson’s diversity index, and evenness were lower than those determined for needles. In terms of the study areas, FLONA-SFP showed higher values of richness, abundance, Simpson’s diversity index, and evenness than PARNA-SJ. Principal coordinate analysis and similarity percentage analysis showed the influence of both substrate factors and areas in the composition of the fungal communities. The presence of new, rare, and affinity-related species reinforces the study of fungi in the context of the conservation of this conifer, as these species are threatened by co-extinction.
Eucalyptus plantations are cultivated worldwide. In Brazil, this crop is widely used for reforestation and production of raw material. Due to that, the Eucalyptus fungal community is promising in ...terms of diversity. A survey of saprobic fungi was carried out on Floresta Estadual Edmundo Navarro de Andrade, Rio Claro, São Paulo, and a member of the family Reticulascaceae was identified. Kylindria eucalypti sp. nov., was found on dead bark of Eucalyptus grandis in Brazil, and it is described, illustrated, and compared with related species. Kylindria is a genus of mainly terrestrial, saprobic, asexually reproducing fungi. The fungus is characterised by its conidiophores with lobed or swollen basal cells, and percurrently extending conidiogenous cells that produce 3-septate conidia with an excentric lateral flat scar. Conidial illustrations of accepted Kylindria species are provided. A dichotomous key and a synoptic table to Kylindria species is presented, and comment is made on a further excluded species, K. conglutinata.
Members of the Diatrypaceae are predominantly saprotrophic on the decaying wood of angiosperms worldwide and the family has received little attention due to its difficult taxonomy. However, the ...recent detection of several pathogenic species, once considered saprotrophic, associated with the wood of diseased grapevines has increased interest in this family. The diversity of tropical species is less well known and more poorly sampled in phylogenetic studies than temperate species. In the present study, we investigated the diversity of diatrypaceous fungi from three areas in the Brazilian semi-arid region and performed phylogenetic analyses of the family based on the entire internal transcribed spacer (ITS) region and partial ß-tubulin gene. Twenty-eight new ITS and 19 new ß-tubulin sequences were generated, representing eight species distributed in five clades.
Diatrypella atlantica
,
Eutypa guttulata
,
Eutypella cearensis
, and
Peroneutypa diminutispora
are proposed here as new species, while
Eutypella microtheca
and
P. curvispora
are new records for Brazil. All eight species are described, illustrated, and discussed.
Brazil is the world’s largest producer of “eucalyptus” and its highest number of species in the country is located at the “Floresta Estadual Edmundo Navarro de Andrade” (FEENA). Despite the historic ...and economic importance of this area, little is known about the fungal community associated with
Eucalyptus
species at FEENA. Here we evaluated the diversity of saprobic fungi in three different stages of
Eucalyptus microcorys
F. Muell leaf litter. In addition, we compared the saprotrophic fungal community with endophytic fungi of
E. microcorys
to assess whether endophytes are also found in the leaf litter. We investigated fungal communities using the particle filtration technique coupled with isolation on two culture media. Fungal isolates were clustered into morphospecies and identified using both morphology and DNA sequences. A total of 2558 fungal isolates were obtained, represented by 48 taxa. We report the following five species for the first time for the American continent:
Castanediella eucalypti
Crous, Hern.-Restr. & M.J. Wingf.,
Harknessia pseudohawaiiensis
Crous & Carnegie,
Neophaemoniella eucalypti
Roon.-Lath. & Crous,
N. niveniae
(Crous) Crous,
Xenogliocladiopsis cypellocarpae
L. Lombard & Crous and
Xyladictyochaeta lusitanica
Hern.-Restr., R.F. Castañeda & Gené. In addition, we found putative new species and well-known fungal pathogens of “eucalyptus” in the leaf litter. The fungal diversity decreased, while the dominance of certain fungal species increased across leaf stages. As expected, the endophytic fungal community significantly differed from communities in the leaf litter. Particularly, only 8 taxa were shared between the leaf types.
Eucalyptus microcorys
hosts a fairly diverse saprobic fungal community on its leaves, which varies with leaf maturity. Exploring the saprobic fungal community is essential for understanding its dynamics in the leaf litter and the trophic interactions with their plant hosts.
This study focused on freshwater hyphomycetes associated with submerged decaying leaves of
Calophyllum brasiliense
in three streams in the semiarid region of Brazil. Leaves were enclosed in litter ...bags and deployed into streams on two occasions (dry and wet seasons). Samples of leaf litter were collected every two months (November 2013 to January 2015). Unlike other studies, we specifically targeted ecologically distinct groups of freshwater hyphomycetes by using two methods to induce fungal sporulation: submerged incubation (SI) of leaf litter on an orbital shaker and incubation in moist chambers (MC). We aimed to analyze and compare the structure of freshwater hyphomycete communities in the streams using both methods, detect possible successional patterns, and evaluate if environmental variables have influenced fungal diversity and sporulation rates. Sixty-nine taxa of freshwater hyphomycetes were observed. Of these, 26 were found under SI and 56 in MC. We observed large differences in fungal communities recovered by SI vs. MC that demonstrates the importance of using several methodological approaches to maximize the number of taxa recovered in ecological studies of litter-associated fungi. The highest sporulation rates under SI were observed during the wet season. Results of community ordination suggested that environmental variables affected the structure of fungal communities; for example, water velocity showed a positive effect on fungal diversity, while higher oxygen availability was associated with lower diversity. This study advances our understanding of the freshwater hyphomycete communities in tropical streams where ecological studies of aquatic fungi are still uncommon.
We examined the mycobiota associated with Vismia guianensis leaf litter in three Atlantic Forest remnants of Brazil＇ s semiarid region. Among the study sites, two remnants were protected forest ...reserves, whereas the third was influenced by major anthropogenic activities. Eighteen litter samples were collected in wet and dry seasons and were processed by particle filtration technique. A total of 4750 fungal isolates of 142 taxa were identified. Species richness was higher in litter samples collected during wet season. Nonmetric multidimensional scaling multivariate analysis showed differences in the composition of fungal communities among the sampling sites and the seasons. Analysis of similarity showed that the differences were statistically significant （R = 0.85; P = 0.0001）. Our findings revealed that spatial and temporal heterogeneity, and human activities had significant impacts on the saprobic fungi of V. guianensis leaf litter.
A new species, Mirandina uncinata, collected on submerged leaves of Calophyllum brasiliense in the Brazilian semiarid region, is described and illustrated. Mirandina uncinata is characterized by ...polyblastic, integrated, terminal, sympodially extended conidiogenous
cells and cylindrical-fusiform, uncinate toward the apex, 5-7-septate, pale brown conidia.
PDF