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Morphological revision and phylogenetic analysis based on nITS and nLSU of specimens previously considered to be a species related to Fulvifomes robiniae from South America revealed a new species of Fulvifomes, i.e. Fulvifomes wrightii. It grows on Libidibia paraguariensis, a Fabaceae distributed in the Chaco Region. The new species is characterised by a perennial, ungulate basidioma with a rimose pileal surface, 6-7 pores per mm, a homogenous context, indistinct stratified tubes and abundant crystals in tube trama and hymenia. Illustrations, taxonomic analyses and a key to the Fulvifomes species recorded from the Americas is provided. [ABSTRACT FROM AUTHOR]

Junghuhnia is a genus of polypores traditionally characterised by a dimitic hyphal system with clamped generative hyphae and presence of encrusted skeletocystidia. However, recent molecular studies revealed that Junghuhnia is polyphyletic and most of the species cluster with Steccherinum, a morphologically similar genus separated only by a hydnoid hymenophore. In the Neotropics, very little is known about the evolutionary relationships of Junghuhnia s.lat. taxa and very few species have been included in molecular studies. In order to test the proper phylogenetic placement of Neotropical species of this group, morphological and molecular analyses were carried out. Specimens were collected in Brazil and used for DNA sequence analyses of the internal transcribed spacer and the large subunit of the nuclear ribosomal RNA gene, the translation elongation factor 1-α gene, and the second largest subunit of RNA polymerase II gene. Herbarium collections, including type specimens, were studied for morphological comparison and to confirm the identity of collections. The molecular data obtained revealed that the studied species are placed in three different genera. Specimens of Junghuhnia carneola represent two distinct species that group in a lineage within the phlebioid clade, separated from Junghuhnia and Steccherinum, which belong to the residual polyporoid clade. Therefore, the new genus Geesterania is proposed including two species, G. carneola comb. nov. and G. davidii sp. nov. Neotropical specimens identified as Junghuhnia nitida represent a different lineage from the European species and are described as Steccherinum neonitidum sp. nov. In addition, the new combinations Steccherinum meridionale, Steccherinum polycystidiferum and Steccherinum undigerum, as well as the new name Flaviporus tenuis, are proposed. [ABSTRACT FROM AUTHOR]

Large numbers of Acacia cyclops trees are dying along the coastal plains of the Eastern and Western Cape Provinces of South Africa. The cause of the deaths has been attributed to a root and butt rot disease caused by the basidiomycete fungus Pseudolagarobasidium acaciicola. However, many signs (e.g. basidiomes) and symptoms reminiscent of Ganoderma root-rot are commonly associated with the dying trees. In this study, isolates collected from basidiomes resembling species of Ganoderma, as well as from root and butt samples from diseased A. cyclops trees were subjected to DNA sequencing and morphological studies to facilitate their identification. Multi-locus phylogenetic analyses and morphological characterisation revealed that three species of Ganoderma are associated with dying A. cyclops trees. These included G. destructans, a recently described species causing root-rot on trees elsewhere in South Africa. The remaining two were novel species, one of which is described here as G. dunense. The novel species is distinguished by its mucronate basidiomes, laccate shiny pileus surface, duplex context and ovoid basidiospores. Only an immature specimen was available for the second species and a name was consequently not provided for it. Interestingly, only a single isolate representing P. acaciicola was recovered in this study, suggesting that further investigations are needed to ascertain the role of each of the four basidiomycetous root-rot fungi in the death of A. cyclops trees. [ABSTRACT FROM AUTHOR]

Summary: Pine plantations in Argentinian Patagonia cover ca. 95,000 ha in Chubut, Río Negro and Neuquén provinces. Exotic bark beetles (Orthotomicus laricis, Hylastes ater and Hylurgus ligniperda) commonly occur in freshly cut logs, stumps and slash. These beetles are vectors of “ophiostomatoid” fungi which include primary tree pathogens as well as important agents of blue stain. The aim of this study was to identify these beetle‐associated fungi. Sawing mills and pine plantations were surveyed three consecutive years. Fungal isolates from stained logs, processed wood and insect galleries were identified based on morphological and DNA sequence comparisons of ITS and β‐tubulin gene regions. Two Grosmannia, one Graphilbum and three Ophiostoma species were identified. Ophiostoma piliferum and O. peregrinum sp. nov. were the most frequently isolated taxa. O. peregrinum occurred in all provinces, colonizing different conifer species and, interestingly, also the native broadleaved species Nothofagus dombeyi. Pine plantation forestry in southern South America includes Argentina, Brazil, Chile, Paraguay and Uruguay. Emerging data from Argentina, Chile and Uruguay revealed some coincidences between these countries, but also several differences, probably, as a result of multiple introduction events. [ABSTRACT FROM AUTHOR]

Arambarria (Hymenochaetales, Basidiomycota) is a monotypic genus recently described to accommodate specimens from the Patagonian forests of Argentina wrongly assigned in the past to Inocutis jamaicensis. On the basis of a wide sampling of strains and phylogenetic analysis inferred from combined sequences including the nuc rDNA ITS1-5.8- ITS2 region, 28S rDNA D1-D2 domains and partial sequences of translation elongation factor 1-a ( tef1-α), we demonstrate that this genus is associated with an important canker rot of eucalypt plantations in Uruguay, to wood rots of many native and exotic hosts, and to 'hoja de malvón' and chlorotic leafroll of grapevines diseases in Central Chile, Central Argentina and Uruguay, formerly assigned to I. jamaicensis and/or Fomitiporella sp. The combined phylogenetic analysis showed the existence of three closely related clades that corresponded to (1) the Pampas of Uruguay and Argentina ('uruguay' clade), (2) the Monte, Chaco Serrano and Yungas forests of Argentina ('cognata' clade) and (3) the Patagonian Andes forests and Chilean Province ('destruens' clade). Lack of morphological differences between taxa from the three clades, their occurrence in both native and exotic hosts, previous results showing interfertility between isolates from Uruguay and Argentina, and the lack of full support in the concatenated ITS + 28S + tef1-α analysis, prevents us to distinguish and describe three different taxa; the proper name of the taxon being Arambarria cognata comb. nov. A fourth, distinctly separated clade corresponded to South African strains isolated from vineyards representing an undescribed taxon associated with Esca grapevine disease in that country. Arambarria is shown to be unrelated to Inocutis, with which it was confused in the past and, so far, remains restricted to the Northern Hemisphere in America (Mexico, Jamaica and the USA). [ABSTRACT FROM AUTHOR]

During a survey of ophiostomatoid fungi in native forests of southern Argentina, several isolates of Huntiella species were obtained from Nothofagus trees. Sequences of multiple gene regions were used to identify these fungi, and their pathogenicity was tested on N. pumilio and N. dombeyi. Phylogenetic analyses revealed a novel taxon described here as H. decorticans sp. nov. Inoculations on N. dombeyi and N. pumilio in the forest showed that H. decorticans is able to produce localized lesions on healthy Nothofagus trees. [ABSTRACT FROM AUTHOR]

Phytophthora austrocedrae is a recently discovered pathogen that causes severe mortality of Austrocedrus chilensis in Patagonia. The high level of susceptibility of the host tree, together with the distribution pattern of the pathogen, have led to the hypothesis that P. austrocedrae was introduced into Argentina. The aim of this study was to assess the population structure of P. austrocedrae isolates from Argentina in order to gain an understanding of the origin and spread of the pathogen. Genetic diversity was determined based on amplified fragment length polymorphisms ( AFLPs). In total, 48 isolates of P. austrocedrae were obtained from infected A. chilensis trees, representing the geographical range of the host. Four primer combinations were used for the AFLP analysis. Of the 332 scored bands, 12% were polymorphic. Gene diversity ( h) ranged from 0·01 to 0·03; the Shannon index ( I) ranged from 0·01 to 0·04. A high degree of genetic similarity was observed among the isolates (pairwise S values = 0·958-1; 0·993 ± 0·009, mean ± SD). A frequency histogram showed that most of the isolate pairs were identical. Principal coordinate analysis using three-dimensional plots did not group any of the isolates based on their geographical origin. The low genetic diversity (within and between sites) and absence of population structure linked to geographic origin, together with the aggressiveness of the pathogen and the disease progression pattern, suggest that P. austrocedrae might have been introduced into Argentina. [ABSTRACT FROM AUTHOR]

Ectomycorrhizal (EM) fungi incorporation in nursery production is necessary for afforestation with exotic tree species and native forests restoration programs. The fact that spore use as EM inocula is inexpensive and effective, makes it an option more realistic than vegetative inoculum production for many regions around the world. To determine spore activity from EM species selected as inoculants for Nothofagus pumilio and exotic conifers planted in Patagonia, two conservation methods were applied (i.e., dried fruit bodies and spore slurries), and their change over time was assessed (over 8-9 months). Spore activity decreased significantly with time for both native and exotic EM species. Conservation methods showed no significant differences for N. pumilio EM species considered together or for exotic conifer EM species. However, spore activity of different EM species behaved differently with conservation method and over time when considered separately. Taxa which better kept spore activity over time were Austropaxillus statuum and Setchelliogaster fragilis for N. pumilio, and Inocybe kauffmanii for exotic conifers. However, considering together fruit body spore density and spore activity, the species Hallingea purpurea and Cortinarius sp. also appeared as suitable for N. pumilio and Rhizopogon roseolus, R. villosulus, Suillus luteus and S. lakei for exotic conifers. Spore density found in EM fungal fructifications were also established in order to estimate fructification weights necessary to apply a reference dose of active spores in inoculation programs. [ABSTRACT FROM AUTHOR]

We surveyed the polypore species associated with living hosts in Argentina. We reviewed the literature on polypores found in Argentina and, in addition with the study of unpublished herbarium material, present a list of 87 species decaying living trees in native forests and introduced plantations. The rot type, host(s), distribution and remarks are presented for each species. Among 87 species found, 71 produce a white rot and 16 a brown rot in wood; 61 species were exclusively found on native hosts and 7 on exotic, cultivated hosts, while 18 were found on both types of substrates; one species, Amylosporus campbellii, was exclusively found associated with grasses. For most cases, there are no pathological studies based on rot measurement and culture isolation to determine incidence and severity of the decay. [ABSTRACT FROM AUTHOR]

We investigated the phylogenetic relationships of Postia species from Patagonia with rDNA ITS and LSU sequences, together with morphological, cultural and biological features. All species in the genus were included in a "Postia clade" irrespective of whether their spores were thin- or thick-walled. This clade is characterized by tetrapolar mating, a normal nuclear behavior, metachromatic generative hyphae and absence of fiber hyphae in culture. One subclade merged the austral taxa P. pelliculosa and P. punctata, but otherwise no distinct relationships were found regarding spore shape, spore wall thickness and geographical distribution of taxa. The austral P. venata and the endemic P. carbophila, with thin-walled basidiospores, occupied variable positions in both analyses. Postia caesia from Patagonia grouped within the P. caesia species complex but on a separate branch. In contrast, P. rennyi and P. balsamea from Patagonia corresponded well with strains from other geographic areas. The two austral species in Ryvardenia, R. cretacea and R. campyla, characterized by non-metachromatic hyphae, bipolar mating and an astatocoenocytic nuclear behavior, formed an independent subclade among the dimitic genera of the "Antrodia clade", far from other Postia taxa within which they had been placed previously, supporting their inclusion in a genus of their own. Postia carbophila grouped with other Postia species and not with Postia (Rhodonia) placenta as suggested previously on the basis of morphological comparisons. Instead, the latter species grouped with taxa in the dimitic genus Amyloporia with which it shares heterocytic nuclear behavior. A separation between specimens of Postia pelliculosa and Ryvardenia cretacea from either side of the Pacific (i.e. SE Australia/New Zealand and S Argentina/S Chile) suggests they could be considered different at the species level from a phylogenetic point of view. [ABSTRACT FROM AUTHOR]

The aim of the present study was to characterise species of Antrodia s.l. from Patagonia, Argentina, and to determine their phylogenetic relationships by using morphological and cultural features as well as mating systems and ITS sequences. Phylogenetic trees generated from maximum-parsimony, neighbour-joining and Bayesian-inference analyses showed that the Argentinean collections were distributed inside the following three main clades: (1) 'Antrodia clade', with Antrodia ramentacea (Berk. & Broome) Donk as a sole representative; (2) 'Amyloporia clade', including Amyloporia nothofaginea Rajchenb. & Gorjón sp. nov. and A. stratosa (J.E.Wright & J.R.Deschamps) Rajchenb., Gorjón & Pildain comb. nov.; and (3) 'Fibroporia clade', with Fibroporia vaillantii (DC.) Parmasto and F. gossypium (Speg.) Parmasto. 'Amyloporia' and 'Antrodia clades' did not have strong molecular support; however, they were well defined with a polyphasic approach when other features such as the number of spore nuclei, mating systems and nuclear behaviour were added. Antrodia includes homothallic to bipolar species, with uni- or binucleate spores and normal nuclear behaviour. Amyloporia includes bipolar to tetrapolar species, with uninucleate spores and heterocytic nuclear behaviour. Fibroporia has strong molecular support and includes tetrapolar species, with uninucleate spores and normal nuclear behaviour. Amyloporia nothofaginea is described as a new species and two new combinations in Amyloporia are proposed. A key to the Antrodia s.l. species present in Patagonia is included. [ABSTRACT FROM AUTHOR]

A number of species in the plant pathogen genus Armillaria are known from South America where they cause root rot disease on a wide variety of hosts. Knowledge pertaining to phylogenetic relationships of these species with those of other Armillaria species is almost non-existent. In addition, very few cultures representing these species are available, making DNA-based phylogenetic analyses impossible. The aim of this study was to characterise a collection of Armillaria isolates from the Patagonian Andes using DNA sequences and to determine their phylogenetic relationships with other Armillaria species. DNA sequences were obtained from the internal transcribed regions (ITS1, 5.8S and ITS4) and ribosomal large subunit (LSU) gene and used in phylogenetic analyses. Phylogenetic trees generated from the sequences separated the Armillaria isolates into four lineages. Lineages I and II represented A. novae-zelandiae and A. luteobubalina, respectively. Isolates belonging to A. novae-zelandiae from Malaysia, New Zealand, Australia and South America showed considerable intra-clade sub-structure. Lineages III and IV are probably distinct species and are most closely related to A. hinnulea and an unnamed species isolated from New Zealand and Kenya. This is the first comprehensive study of the phylogenetic relationships of Armillaria species from Patagonia and it provides a foundation for future research in this region. [ABSTRACT FROM AUTHOR]

Austrocedrus chilensis forests in Argentina suffer a widespread mortality, locally known as `mal del ciprés', whose causes remain unknown. `Mal del ciprés' occurs throughout the cypress range in Argentina, being Río Grande Valley, in Central Patagonian Andes, an area where the disease has notoriously increased its extension and importance in the last years. The purpose of this work was to characterize Río Grande Valley soils where declining cypress stands develop and to determine what soil properties are associated with the disease. Four sampling sites with pure cypress forests expressing `mal del ciprés' were selected. In each of them, 3 declining and 3 asymptomatic plots were established and were characterized by edaphic features. Selected morphological, physical and chemical soil properties were related to the occurrence of the decline by means of analysis of variance. The cypress forest developed in a wide range of soils with different parent materials: glacifluvial, alluvial, volcanic with a glacifluvial discontinuity, volcanic on an andesitic substratum, and soils derived from andesite alteration. All the soils presented dark superficial horizons, rich in organic matter and with granular structure. Cypress growing on volcanic soils with a glacifluvial discontinuity presented symptoms of decline in areas where the discontinuity, and therefore the clayey horizon and the redoximorphic features, were close to the surface. In soils derived from andesite alteration, the declining forest was also present on shallow soils with redoximorphic features near the surface. In volcanic soils with a lithological discontinuity of andesite, the decline was restricted to areas near a water stream. In alluvial soils, declining trees appeared related with the flood plain of the river; healthy forest stands developed on higher lands, where soils were well drained. Glacifluvial soils, presenting clayey textures and great difficulties for rooting, were the soils submitted to the worst drainage conditions. In these soils, the decline presented a random pattern of distribution, suggesting that the whole area is prone to develop the decline. Results showed cypress capacity to inhabit different soils; however microsite features related to poor drainage (i.e., low slope, nearness to water streams, the presence of clay and redoximorphic features near to the surface) determined a higher risk of disease occurrence. [ABSTRACT FROM AUTHOR]

In this article, the presence of basidiomes of wood-decay fungi on living lenga (Nothofagus pumilio) was investigated in seven forest stands in Patagonia (Argentinia). The following species accounted for 85% of the rots: Postia pelliculosa, Phellinus andinopatagonicus, Piptoporus portentosus, Aurantioporus albidus, and Serputa himantoides. Ph. andinopatagonicus and A. ailbidus cause characteristic white rots, while the other tree species cause unspecific, cubical brown rots. Piptoporus portentosus probably infected only through the canopy, while A. albidus and S. himantoides did so through the roots.