The aim of this work is to contribute to the knowledge of the diversity of stereoid fungi growing in the Patagonian Andes. In a recent survey we have found a species of Stereodiscus growing on Nothofagus antarctica in Southern Argentina, closely related to Stereodiscus trivialis but with distinct smaller basidiospores and characteristically encrusted pseudocystidia. The new species is described based on morphological features and phylogenetic ITS and 28S nuc-LSU data. In addition, a key to the known species of Stereodiscus is provided.

This work reports the first survey of Phytophthora diversity in the forests soils of Andean Patagonia. It also discusses the role of anthropogenic impact on Phytophthora distribution inferred from the findings on Phytophthora diversity and on the distribution of Phytophthora austrocedri-diseased forests. Invasive pathogen species threatening ecosystems and human activities contribute to their entry and spread. Information on pathogens already established, and early detection of potential invasive ones, are crucial to disease management and prevention. Phytophthora austrocedri causes the most damaging forest disease in Patagonia, affecting the endemic species Austrocedrus chilensis (D. Don) Pic. Sern. and Bizzarri. However, the relationship between anthropogenic impacts and the disease distribution has not been analyzed enough. The aims of this work were: to evaluate Phytophthora diversity in soils of Andean Patagonia using a metabarcoding method, and analyze this information in relation to soil type and land use; to assess the distribution of Austrocedrus disease over time in relation to anthropogenic and abiotic gradients in an area of interest; and to discuss the role of human activities in Phytophthora spread. High throughput Illumina sequencing was used to detect Phytophthora DNA in soil samples. The distribution of Austrocedrus disease over time was assessed by satellite imagery interpretation. Twenty-three Phytophthora species, 12 of which were new records for Argentina, were detected. The most abundant species was P. austrocedri, followed by P. × cambivora, P. ramorum and P. kernoviae. The most frequent was P. × cambivora, followed by P. austrocedri and P. ramorum. Phytophthora richness and abundance, and Austrocedrus disease distribution, were influenced by land use, anthropogenic impact and soil drainage. Results showed several Phytophthoras, including well-known pathogenic species. The threat they could present to Patagonian ecosystems and their relations to human activities are discussed. This study evidenced the need of management measures to control the spread of P. austrocedri and other invasive Phytophthora species in Patagonia.

Summary: Fosetyl‐Al and metalaxyl, the most commonly used systemic fungicides against Phytophthora, were evaluated for their efficacy to control Phytophthora austrocedri, the pathogen that causes a serious disease at the Austrocedrus chilensis forests in Patagonia. The effect of the chemicals on pathogen development in vitro and in planta was analysed. Both chemicals were shown to protect plants from the pathogen. In vitro assays showed that asexual reproduction was sensitive to both chemicals. However, mycelial growth and sexual reproduction, which were clearly sensitive to metalaxyl, were sensitive only to high concentrations of fosetyl‐Al. Fosetyl‐Al and metalaxyl had almost the same efficacy when applied preventively by soil drench to seedlings. This difference between in vitro and in planta results can be attributed to the dual action of fosetyl‐Al, not only inhibiting the pathogen but also stimulating host defence. In adult trees, preventive and curative treatments were tested, but only the fosetyl‐Al preventive treatment was effective in the assayed conditions. Interestingly, seedlings pretreated with both fungicides were less susceptible to the effectors secreted by the pathogen. Our results indicate that fosetyl‐Al and metalaxyl provide some resistance to the plant besides the fungistatic direct action on the pathogen. Further studies to elucidate a possible resistance‐inducing activity of these chemicals and the mechanisms involved are underway.

Patagonian collections of the corticioid genus Tomentellopsis have been treated in the past as T. echinospora, a common northern hemisphere species. New collections with DNA sequence data are distinct from the northern hemisphere taxon and must be considered a different species, endemic to the temperate subantarctic forests of Patagonia. We use molecular and morphological methodologies to study this new corticioid fungus and describe it as Tomentellopsis rosannae sp. nov.

Solid-state fermentation of cereals with edible fungi is a promising strategy for producing functional flours. Hypothetically, the nutritional and functional properties of these flours could be modulated by manipulating substrate composition, fungal species, and incubation conditions. This article reports the variation over time in nutritional, polyphenol, and triterpene contents, as well as the antioxidant activity of rice and wheat fermented with Ganoderma sessile and Pleurotus ostreatus. Solid-state fermentation significantly improved the antioxidant power of the substrates which seemed to be highly correlated with the increase of the phenolic compounds. This increase peaked in the second to third week and decreased after this point. Triterpene content also increased, especially in substrates fermented with G. sessile. Substrates fermented with G. sessile showed higher values than those fermented with P. ostreatus in all compounds, which could be a result of a higher growth rate. Fermented wheat showed higher values than fermented rice in all measured compounds except reducing sugars which can be related to a slower progress in the fermentation due to the more complex structure of the wheat grain. Our results reinforce the importance of substrate and strain selection for product modulation to meet the industry's growing needs.

Wheat and rice are major sources of human nutrition worldwide. Solid-state fermentation (SSF) with lignocellulolytic mushrooms can enhance their nutritional value and increase their functional properties. However, this technology is not yet widely applied. In this work, whole wheat and brown rice hydrated to 60% were used as substrates for the edible mushroom Pleurotus ostreatus and the medicinal Ganoderma sessile, which were incubated for 14 days at 25 °C in the dark. The fermented substrate biomass was incorporated into standard sugar-snap cookie recipes, substituting 20% of the wheat flour. We evaluated the technological and nutritional properties of alternative fermented flours and cookies. Both the fermented flours and cookies exhibited increased soluble and total protein content, antioxidant power, and phenol content, indicating overall functional improvement. Fermented G. sessile flour also showed increased triterpenoid content. The physical quality of cookies remained within expected ranges, demonstrating the feasibility of the application. These results highlight the potential of SSF as a method for nutritional and functional enrichment of grains and extend the health benefits of mushrooms to populations relying on low-cost, grain-derived carbohydrates. Further studies on digestibility and in vivo activity of metabolites are needed to confirm the potential health benefits of fermented flours.