María Virginia Bianchinotti

The phylogenetic position of poroid Hymenochaetaceae (Hymenochaetales, Basidiomycota) from Patagonia, Argentina

Six poroid Hymenochaetaceae from Patagonia, Argentina, were studied phylogenetically with nuc rDNA internal transcribed spacer (ITS) and partial 28S rDNA sequences, together with morphological data. Two new genera and a new species are introduced as well as two new combinations proposed. Arambarria destruens gen. et sp. nov. is proposed for a taxon fruiting on fallen or standing, dead Diostea juncea and Lomatia hirsuta and previously recorded erroneously as Inocutis jamaicensis; it is distinguished by annual, effused to effused-reflexed basidiomes forming pilei, a monomitic hyphal system, thick-walled and yellowish basidiospores (brownish chestnut in potassium hydroxide solution), lack of a granular core in the context and lack of setoid elements. Nothophellinus gen. nov. is proposed to accommodate Phellinus andinopatagonicus, the main white wood-rotting polypore of standing Nothofagus pumilio and also an important wood-decayer of other Nothofagus species from southern Argentina and Chile. It is morphologically similar to Phellopilus (type species P. nigrolimitatus) but differs by lacking setae. The new combinations Pseudoinonotus crustosus and Phellinopsis andina are proposed for Inonotus crustosus and Phellinus andinus, respectively. Phellinus livescens, which decays the sapwood of several standing Nothofagus species, is closely related to Phellinus uncisetus, a Neotropical species related to Fomitiporia; for the time being P. livescens is retained in Phellinus sensu lato. An unidentified taxon responsible for a white heart-rot in living Austrocedrus chilensis grouped with Phellinus caryophyllii and Fulvifomes inermis, but its generic affinities remain ambiguous. Transmission electron microscopy studies confirm this unidentified taxon has an imperforate parenthesome, which is typical of the Hymenochaetaceae.

Inferencias paleoecológicas a partir del análisis de microfósiles fúngicos en una turbera pleistoceno-holocena de Tierra del Fuego, Argentina

Palaeoecological inferences from the analysis of fungal microfossils of a mire in Tierra del Fuego, Argentina. this paper presents the fungal remains recovered from the fossil peat sequence at La correntina mire (S 54° 33 W 67°), located in the central part of Isla Grande de tierra del Fuego, Argentina. newly recognised fungal microfossils have distinctive morphological features that allow their systematic classification. representatives of Glomeromycota (1), Ascomycota (7), mitosporic fungi (4) and three types of spores without taxonomic rank are identified and described. this study represents a contribution to the knowledge of the fossil fungal remains and provides data about their ecological implications.

Micromycetes on Austrocedrus chilensis. First record of Rebentischia from Argentina

Fil: Bianchinotti, Maria Virginia. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Bahia Blanca. Centro de Recursos Naturales Renovables de la Zona Semiarida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiarida; Argentina

Parenthesome structure of some corticioid fungi

The parenthesome structure of seven corticioid species, traditionally referred to the family Corticiaceae (Basidiomycota), were studied in order to better understand their taxonomic position: Phanerochaete velutina, Phlebia radiata, P. rufa, Rhizochaete americana (syn. Ceraceomyces americana), R. brunnea, R. filamentosa (syn. Phanerochaete filamentosa) and R. radicata (syn. Phanerochaete radicata). All possessed the perforate type of parenthesome that is commonly encountered in homobasidiomycetes. This feature excludes the above taxa from both the hymenochaetoid and the cantharelloid clades which are the only groups that have imperforate parenthesomes in the homobasidiomycetes.

A new species of Pseudorobillarda from a leguminous tree in Argentina.

Pseudorobillarda magna sp. nov. from bark of Geoffroea decorticans, a native tree of Argentina, is described and illustrated. It is compared with the known species in the genus. This is the first report of a species of Pseudorobillarda from South America.

On the presence of imperforate parenthesomes in Daedalea sprucei and its taxonomical disposition

Daedalea sprucei is shown to possess imperforate parenthesomes, which suggests an affinity with the genus Trichaptum . This affinity is corroborated by other features such as the violet colouration of the fruit body when fresh, the presence of characteristic hymenial cystidia and spores, similar cultural characters, an association with a white rot in the wood and tetrapolar sexuality. The new combination Trichaptum sprucei is proposed.

Estimación de la biomasa fúngica en un suelo del sudoeste de la provincia de Buenos Aires (Argentina) con una tinción directa con blanco de calcoflúor

Soil microorganisms are vital for ecosystem functioning because of the role they play in soil nutrient cycling. Agricultural practices and the intensification of land use have a negative effect on microbial activities and fungal biomass has been widely used as an indicator of soil health. The aim of this study was to analyze fungal biomass in soils from southwestern Buenos Aires province using direct fluorescent staining and to contribute to its use as an indicator of environmental changes in the ecosystem as well as to define its sensitivity to weather conditions. Soil samples were collected during two consecutive years. Soil smears were prepared and stained with two different concentrations of calcofluor, and the fungal biomass was estimated under an epifluorescence microscope. Soil fungal biomass varied between 2.23 and 26.89μg fungal C/g soil, being these values in the range expected for the studied soil type. The fungal biomass was positively related to temperature and precipitations. The methodology used was reliable, standardized and sensitive to weather conditions. The results of this study contribute information to evaluate fungal biomass in different soil types and support its use as an indicator of soil health for analyzing the impact of different agricultural practices.

Two new lignicolous species of Nitschkia from Argentina

Two species of Nitschkia are described from bark and wood of a legume shrub, native to the semiarid regions of Argentina. Nitschkia campylospora is characterized by asci with a variable number of ascospores, mainly 16, and curved ascospores; hairy ascomata and large ascospores are two distinct features of Nitschkia pilosa. The new species are compared with most similar species. A key to Nitschkia species is provided with the inclusion of comments on those from Argentina and neighboring countries.