Microscopic fungi in the Atlantic Rainforest in Cubatão, São Paulo, Brazil

This article presents a survey of fungi obtained from soil, water and mixed leaf litter samples taken from the Atlantic Rainforest in the municipality of Cubatão, in the State of São Paulo, during the years of 1993 to 1995. Using different techniques for the isolation of microscopic fungi, a total of 280 taxa was obtained (66 zoosporic fungi, 40 Mucorales, 45 Glomales, 125 anamorphs, three Ascomycota and one Basidiomycota), with 23 species being reported for the first time in Brazil.

Este artigo apresenta o levantamento dos fungos obtidos de amostras de solo, água e folhedo mixto coletados da Mata Atlântica no município de Cubatão, estado de São Paulo, durante os anos de 1993 a 1995. Utilizando diferentes técnicas para isolamento de fungos microscópicos, um total de 280 táxons foram obtidos (66 fungos zoospóricos, 40 representantes de Mucorales, 45 de Glomales, 125 fungos anamorfos, três de Ascomycota e um representante de Basidiomycota), sendo 23 espécies reportadas pela primeira vez para o Brasil.

Sexual reproduction in subcultures of Absidia blakesleeana after years of preservation under mineral oil.

Two subcultures of Absidia blakesleeana IOC No. 2425 (-) mating type strain preserved in 1959 and 1981 on a thick layer of potato dextrose agar (PDA) medium under sterile mineral oil and maintained at room temperature in the Fungal Cultural Collection of Institute Oswaldo Cruz--IOC--were paired with the defined Absidia blakesleeana URM-UFP No. 2076 (+) mating type strain. Portions of the line where mycelia of the two strains met were observed under light microscopy. Zygospores belonging to Subgenus Mycocladus were observed. The results demonstrated conservation and re-establishment of the physiological and genetic metabolic processes of two subcultures preserved under mineral oil.

Morphological observations on Absidia corymbifera and Absidia blakesleeana strains preserved under mineral oil.

Macro- and micromorphology of 30 living subcultures of Absidia corymbifera (10 strains plus three strains of Absidia ramosa) and Absidia blakesleeana (two strains) preserved under mineral oil at room temperature for periods ranging from 3 to 44 years in The Fungal Culture Collection of Instituto Oswaldo Cruz (IOC) were observed and described by permanent mycological preparations mounted in a glycerol 10% and/or Amann lactophenol solution. Vegetative and asexual reproductive structures are illustrated by drawings made with the aid of a camera-lucida. The study showed that the period of maintenance under mineral oil and the stress which took place during the period of storage did not affect the vegetative and asexual reproductive morphology of the Absidia strains and species studied here.

Arbuscular mycorrhizal fungi associated with Araucaria angustifolia (Bert.) O. Ktze.

Specimens of Araucaria angustifolia from a native forest reserve and a reforested area in the State Park of Campos do Jordão were studied to determine the number and diversity of spore populations of arbuscular mycorrhizal fungi (AMF) and root colonization. Six randomly chosen plots (planted with 8- to 12-year-old plants) were delimited, four in the native forest and two in the reforested area. Rhizosphere and root samples were collected during two periods of the year corresponding to the rainy and dry seasons. A greenhouse experiment was set up for multiplication of field propagules (from the native forest and reforested area) for two consecutive generations. Araucaria leaves from the experimental plots were collected during the first sampling for nutrient analysis. Twenty-four AMF taxa were found and percent AM colonization was determined in all plots. Not all AMF species observed in the field were re-isolated through the recovery pot cultures, even after a second cultivation cycle. The foliar nutrient analysis showed higher nutrient levels in plants from the native forest than the reforested area. Generally, spore richness and diversity were highest during the warmer and more humid period and in the native forest plants.

Airborne fungi in the region of Cubatäo, Säo Paulo state, Brazil

From March/1993 to March/1995, airborne fungi were isolated from the "Vale do Rio Moji" (highly affected by the air pollution caused by fertilizer industries, steel works, cement factories and chemical products industries, among others) and from the "Vale do Rio Pilões" (less affected by the air pollution), both in the municipality of Cubatão, São Paulo State, Brazil, by exposing Petri dishes with potato dextrose agar medium, placed one meter from the ground, during 5 min. After 5 days of incubation at 20§C, the colonies of the fungi were purified and identified, resulting in the identification of 39 taxa, three unidentified strains of Fusarium and non-sporulating cultures. A total of 28 taxa, one unidentified strain of Fusarium and non-sporulating fungi (71 records) were isolated in the "Vale do Rio Moji" and 29 taxa, two unidentified strains of Fusarium and non-sporulating fungi (72 records) in the "Vale do Rio Pilões. The airborne mycota of the higher polluted site presented 17 common, 12 rare and only one constant fungal species. In the other site, the airborne mycota was composed by 19 common, 10 rare and two constant fungal species. Among the obtained fungi, at least 12 taxa were reported as opportunistic fungi, 26 have been mentioned related to plant diseases and eight have been associated to allergy problems. The similarity Index of Sörensen between the mycotas, corresponding to 58 per cente, may be considered low, and is probably justified by the air pollution, that mainly distinguish the two studied areas.