Margarida Barata

Marine fungi from Mira river salt marsh in Portugal

The occurrence of fungi in the Mira salt marsh, Portugal was investigated for 12 months. Baits of Spartina maritima stems were exposed to permanent or temporary submersion at the upper and lower limits of the intertidal zone. The baits were observed for fruit bodies and spores directly and after incubation in moist chambers. Twenty six marine species were identified (17 Ascomycota, two Basidiomycota and seven mitosporic fungi). Twenty four are new records for Portugal. Nia globospora Barata and Basílio was published as a new species. Species were characterized with respect to frequency of occurrence, colonization capability and substrate succession. The diversity and similarity indexes of the fungi under different conditions were determined.

Use of drift substrates to characterize marine fungal communities from the west coast of Portugal

This survey reports the occurrence, diversity and similarity of marine fungi associated with five categories of drift substrates (Arundo donax, Phragmites australis, Spartina maritima, “other stems” and driftwood) collected on four sandy beaches of the western coast of Portugal. “Other stems” and driftwood are composite samples with a variety of identified and unidentified pieces of non-woody and woody substrates respectively. Fifty-six taxa were identified, including 38 Ascomycota and 18 anamorphic fungi. Twenty-six taxa were generalists; however several cases of “substrate recurrence” were identified. The very frequent fungi differed among the categories of studied substrates, with the exception of Corollospora maritima, very frequent on four categories. Except for S. maritima, P. australis and driftwood, cases of multiple fungal colonization were rare. S. maritima was the single substrate with five different marine fungi on one sample, as well as with the highest number of very frequent fungi, highest percentage of colonization and average number of fungi per sample. Driftwood presented the highest value of fungal richness (37 taxa) and A. donax the lowest (22 taxa). ANOSIM analysis of similarity showed that all substrates supported different fungal communities with the exception of the pair P. australis/”other stems”. The effect of sample size on estimated fungal richness was tested, and the results let us conclude that, although most of the sporadic fungi (<1% occurrence) will be detected only in a very large number of samples, 60 samples of A. donax and “other stems” and 70 samples of all the other substrates may suffice to assess their respective representative marine mycota.

Diversity and Ecological Characterization of Sporulating Higher Filamentous Marine Fungi Associated with "Spartina maritima" (Curtis) Fernald in Two Portuguese Salt Marshes

Fungal communities associated with early stages of decomposition of Spartina maritima (Curtis) Fernald were assessed in two geographically distinct salt marshes in Portugal by direct observation of fungal sporulating structures. Twenty-three fungal taxa were identified from 390 plant samples, 11 of which were common to both study sites. Natantispora retorquens, Byssothecium obiones, Phaeosphaeria spartinicola, Phoma sp. 1 and Stagonospora sp. were the most frequent fungal taxa in the studied communities. The fungal species Anthostomella spissitecta, Camarosporium roumeguerii, Coniothyrium obiones, Decorospora gaudefroyi, Halosarpheia trullifera, Leptosphaeria marina and Stagonospora haliclysta were recorded for the first time on S. maritima plants; with the exception of C. roumeguerii and L. marina, all of these species were also new records for Portugal. The differences between species composition of the communities associated with S. maritima were attributed to differences in abiotic conditions of the salt marshes. Although the fungal taxa were distributed differently along the host plants, common species to both fungal communities were found on the same relative position, e.g. B. obiones, Lulworthia sp. and N. retorquens occurred on the basal plant portions, Buergenerula spartinae, Dictyosporium pelagicum and Phoma sp. 1 on the middle plant portions and P. spartinicola and Stagonospora sp. on the top plant portions. The distinct vertical distribution patterns reflected species-specific salinity requirements and flooding tolerance, but specially substrate preferences. The most frequent fungi in both communities also exhibited wider distribution ranges and produced a higher number of fruiting structures, suggesting a more active key role in the decay process of S. maritima.

BIODIVERSITY OF FILAMENTOUS FUNGI ON SOILS AND SANDS

The diversity of soil organisms is more extensive than in any other existing environment as far as the living forms are considered. The soil biota contains representatives of all groups of microorganisms (fungi, bacteria, algae and viruses), as well as microfauna, such as protozoa and nematodes (Campbell and Puri, 2002).

Lulworthia atlantica: a new species supported by molecular phylogeny and morphological analysis

ABSTRACT This study presents morphological and molecular evidence for the establishment of a new species of Lulworthia based on the evaluation of 11 isolates of Lulworthiales collected in two marinas on the west coast of Portugal initially classified as Lulworthia sp. Maximum likelihood and Bayesian methods were applied to obtain phylogenetic trees for 18S-28S and internal transcribed spacer (ITS1-5.8S-ITS2 = internal transcribed spacer [ITS]) nuc rDNA. The isolates consistently grouped together in a distinct and highly supported clade; all other Lulworthiales analyzed, including the available sequences of Lulworthia spp., segregated separately. These results were supported by common and distinctive morphological characters and enabled recognition and description of the new species Lulworthia atlantica. Two Portuguese isolates were confirmed as Lulworthia cf. purpurea, and two were confirmed as asexual morphs of Zalerion maritima.

Portuguese marine fungi and the contribution of differential interference contrast (DIC) microscopy for their morphological identification

Marine fungi occur either in Open Ocean or in the intertidal zone of sandy beaches, salt marshes and mangroves, where their hosts and substrates are found. The development of morphological adaptations like appendages and sheaths of the spores are vital to the settlement and attachment to substrate surfaces, floatation and dispersion on seawater. The morphological features of these appendages and sheaths of spores also have an important role in the identification of marine fungi. Differential interference contrast (DIC) microscopy is an essential tool for the observation of these mucilaginous structures in marine fungi spores and was therefore applied to marine mycota from surveys along the Portuguese coast.