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A new monotypic sequestrate genus, Longistriata is described based on collections from the Neotropical forest of Atlantic forest in Paraíba, Northeast Brazil - an area known for its high degree of endemism. The striking features of this new fungus are the hypogeous habit, the vivid yellow peridium in mature basidiomes, broadly ellipsoid basidiospores with a distinct wall that is ornamented with longitudinal striations and lageniform cystidia with rounded apices. Phylogenetic analysis, based on LSU and tef-1α regions, showed that the type species, Longistriata flava, is phylogenetically sister to the monotypic sequestrate African genus Mackintoshia in Boletaceae. Together these two species formed the earliest diverging lineage in the subfamily Zangioideae. Longistriata flava is found in nutrient-poor white sand habitats where plants in the genera Coccoloba (Polygonaceae) and Guapira (Nyctaginaceae) are the only potential ectomycorrhizal host symbionts.

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Sulfate-reducing bacteria (SRB) and a biochar array were used to reduce sulfate concentrations and the levels of metals in acid mine drainage (AMD) waters. Cow manure SRB-enriched biochar promoted sulfate reductions of 41% compared to original AMD, and 39% compared to other treatments (control, AMD sediment, sludge). Treatments reduced levels of all analyzed metals below Brazilian official standards. DGGE showed a significant relation between SRB-source and SRB-structural community, where cow manure and sludge presented the more cohesive community structure throughout the monitoring (180 days). The study showed that AMD treatment alternatives can be applied and are effective in reducing the contamination of wastewaters.

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Restingomyces reticulatus gen. et sp. nov. is a recently discovered false truffle species from Atlantic "restinga" rainforest in northeastern Brazil. Molecular and morphological characters separate this new sequestrate species from other described taxa in the order Phallales (Phallomycetidae, Basidiomycota). In our phylogenetic analysis based on nuc 28S rDNA and atp6, R. reticulatus forms a sister clade to Trappea darkeri and Phallobata alba, with the three taxa forming the earliest diverging lineage within Phallales. Morphological and molecular data warrant the recognition of the new genus and species, described here, and we also amend the taxonomic description for the family Trappeaceae.

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The occurrence of high levels of Cu in vineyard soils is often the result of intensive use of fungicides for the preventive control of foliar diseases and can cause toxicity to plants. Nowadays many grape growers in Southern Brazil have replaced Cu-based with Zn-based products. The aim of the study was to evaluate whether the increase in Zn concentration in a soil with high Cu contents can interfere with the dynamics of these elements, and if this increase in Zn may cause toxicity to maize (Zea mays L.). Soil samples were collected in two areas, one in a vineyard with more than 30 years of cultivation and high concentration of Cu and the other on a natural grassland area adjacent to the vineyard. Different doses of Cu and Zn were added to the soil, and the adsorption isotherms were built following the Langmuir's model. In a second experiment, the vineyard soil was spiked with different Zn concentrations (0, 30, 60, 90, 180, and 270mg Zn kg(-1)) in 3kg pots where maize was grown in a greenhouse for 35 days. When Cu and Zn were added together, there was a reduction in the quantities adsorbed, especially for Zn. Zn addition decreased the total plant dry matter and specific leaf mass. Furthermore, with the increase in the activity of catalase, an activation of the antioxidant system was observed. However, the system was not sufficiently effective to reverse the stress levels imposed on soil, especially in plants grown in the highest doses of Zn. At doses higher than 90Znmgkg(-1) in the Cu-contaminated vineyard soil, maize plants were no longer able to activate the protection mechanism and suffered from metal stress, resulting in suppressed dry matter yields due to impaired functioning of the photosynthetic apparatus and changes in the enzymatic activity of plants. Replacement of Cu- by Zn-based fungicides to avoid Cu toxicity has resulted in soil vineyards contaminated with these metals and damaging of plant photosynthetic apparatus and enzyme activity.

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The abundance and diversity of ectomycorrhizal fungi (EMF) was assessed based on the collection of basidiocarps during 12 months comprising the spring of 1995, and the summer, autumn, and winter of 1996, in three stands of young, middle-aged, and rotation age plantations of Pinus taeda and Eucalyptus dunnii, in the state of Santa Catarina, southern Brazil. A total of 3,085 collections yielded 34 presumed EMF taxa in ten genera, including mushroom-like and sequestrate species. Fruiting patterns of EMF differed with host and season, and host specificity was apparent in some. The overall relative importance (RI) and the Shannon diversity index (H) suggested that stands of E. dunnii had a more diverse aboveground EMF community than those of P. taeda. Overall, species of Scleroderma and Laccaria were not only the most abundant but also had the highest biomass values. The results show that a small number of species of abundant biomass and a larger number of species of less-abundant biomass characterize each forest class.

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