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The aims of this study were to prospect Penicillium and Talaromyces species associated with Austrocedrus chilensis in sites with and without Austrocedrus Root Disease (ARD), which is caused by the pathogen Phytophthora austrocedri; and to find Penicillium sp. strains with biocontrol activity against this disease. Isolations from sites with and without the prevalence of ARD were made, and the obtained isolates were phenotypically and molecularly identified to species level. Several Penicillium species were isolated from all sites; five of them were exclusively isolated from sites with ARD. Penicillium communities were compared through multivariate analyses; communities were more complex in sites with ARD. Biocontrol activity of Penicillium and Talaromyces isolates was evaluated using co-cultures with Ph. austrocedri. Penicillium glabrum, T. amestolkiae, P. palitans, and P. crustosum showed the highest biocontrol effect. Our results highlight that Penicillium species have high biocontrol activity, which also reinforces the hypothesis that some Penicillium species could be used in formulating a control strategy. [ABSTRACT FROM AUTHOR]

Attine ants are a monophyletic group comprising more than 230 species, distributed exclusively in the New World. All higher Attini ants depend on the cultivation of fungus gardens for food, and those gardens are continuously exposed to alien microorganisms. The present work describes, for the first time, the composition, relative frequency and the richness of the fungal species comprising the mycobiota from the garden of the most abundant Acromyrmex species from different regions of Argentina. We also compared, using a multivariate approach, the mycobiota composition with the purpose of testing two hypotheses: 1) whether mycobiota is defined by the ant species, or 2) whether mycobiota is determined by the geographical region. We found that each fungal community had a particular composition and abundance: the species that were highly frequent in a community or site, could be rare or altogether absent in another community or site. Species richness, as well as the theoretical maximum richness, also changed with locations. Furthermore, we found that different ant species at the same site had similar mycobiotas, whereas the same ant species in distant locations had only a few fungal species in common. Therefore, we concluded that mycobiota composition changed considerably with geographical site and was not dependent on the ant species. Our results provide an additional understanding of the leaf cutting-ants system, confirming that the garden of leaf cutting ants nests is a complex and dynamic fungal community which is dependent on the site where it was located. [ABSTRACT FROM AUTHOR]