From visit to emergence: Interactions between mycophagous Drosophilidae (Insecta, Diptera) and macroscopic fungi (Basidiomycota) and their patterns in ecological networks

ABSTRACT Ecological interactions are diverse, variable across space and time and not always well understood. The use of interaction network analysis has become a tool that promotes a deeper understanding on ecological and evolutionary processes. The interaction between insects and fungi is an interesting research model, helping to understand colonization dynamics and species specialization in spatially aggregated and ephemeral resources. Here, we describe the interactions between Drosophilidae species and the fungal basidiocarps in a subtropical forest in Brazil. Flies were collected when were visiting basidiocarps and then the basidiocarps themselves were also collected to obtain the emerging flies whose larvae fed on the fungi. We observed 31 species of drosophilids interacting with basidiocarps of 23 fungi species. An ecological network analysis was performed for the drosophilids breeding on basidiocarps and for those visiting them as adults. We found a specialized breeding network, with stronger interactions involving Hirtodrosophila and Auricularia and Zygothrica bilineata and a Marasmius species. Our results indicate the generalist habit of most Zygothrica species. The visitation network was highly specialized. Despite being well represented in the sampling, most Zygothrica species did not emerge from any fungal species. This study advances the knowledge on patterns of Drosophilid-fungi interactions and provides insights into their drivers.

Mushroom extract of Lactarius deliciosus (L.) Sf. Gray as biopesticide: Antifungal activity and toxicological analysis.

Monilinia fructicola (Wint.) Honey is a plant pathogenic fungus that infects stone fruits such as peach, nectarine and plum, which are high demand cultivars found in Brazil. This pathogen may remain latent in the host, showing no apparent signs of disease, and consequently may spread to different countries. The aim of this study was to evaluate the activity of hydroalcoholic extract (HydE) obtained from Lactarius deliciosus (L.) Sf. Gray a mushroom, against M. fructicola phytopathogenic-induced mycelial growth. In addition, the purpose of this study was to examine phytotoxicity attributed to HydE using Brassica oleracea seeds, as well as cytotoxic analysis of this extract on cells of mouse BALB/c monocyte macrophage cell line (J774A.1 cell line) (ATCC TIB-67). The L. deliciosus HydE inhibited fungal growth and reduced phytopathogen mycelial development at a concentration of 1.25 mg/ml. Our results demonstrated that the extract exhibited phytotoxicity as evidenced by (1) interference on germination percentage and rate index, (2) decreased root and initial growth measures, and (3) lower fresh weight of seedlings but no cytotoxicity in Vero cell lines. Data suggest that the use of the L. deliciosus extracts may be beneficial for fungal control without any apparent adverse actions on mouse BALB/c monocyte macrophage cell line (J774A.1 cell line) viability.

Bioassays for the evaluation of reclaimed opencast coal mining areas.

This study aimed to use bioassays (single and multispecies) with organisms from different trophic levels to assess soil quality in reclaimed coal mining areas. Soil samples were collected from four sites: two sites with recent reclaim processes (one using topsoil and other using clayey soil), an natural attenuation site, and a control soil. The evaluated parameters were divided into (1) ecotoxicological tests (avoidance test with Eisenia andrei (earthworms) and Armadillidium vulgare (isopods); germination test with Sinapis alba seeds (mustard); reproduction tests with Folsomia candida (collembolans); bacterial toxicity test); (2) population and community assessments (a fungal count; microbial community analysis using Biolog EcoPlatesTM); (3) microcosms scale evaluation (the MS-3 multispecies system); and (4) chemical analysis (soil parameters, soil metal, and cations and anions in soil leachate). Results pointed to toxicity in the natural attenuation site that compromised of habitat function, probably due to low pH and low nutrient levels. The most recent reclaim process, using topsoil and clay soil, improved soil quality and fertility, with a further increase in habitat quality and heterogeneity. This study shows that some techniques used to reclaim degraded mining areas are effective in rebuilding habitats, sustaining soil biota, and reestablishing ecosystem services.

Biological activity of aqueous extracts of Southern Brazilian mushrooms.

This study aims to perform a bioactive analysis of five mushrooms collected in south of Brazil. The total phenol content of the extracts was equivalent to the antioxidant activity by ACAP assay. All extracts were able to inhibit the growth of Acinetobacter baumanni, and Auricularia auricula and Lactarius deliciosus extract showed the best antibacterial activity. In addition, no extract showed cytotoxic activity against VERO cells at the highest concentration evaluated (2500 µg/mL). Our results showed better antioxidant activity through the inhibition of the oxidation via peroxyl radical. It can be observed that all extracts were active against A. baumanni, and even moderately, all extracts could be inhibited of at least one of the bacteria used in the study. Added for these, the aqueous extracts showed no toxicity in VERO cells, highlighting the importance of research about the active compounds of mushrooms of the region.

Larvicidal efficiency of the mushroom Amanitamuscaria (Agaricales, Amanitaceae) against the mosquito Culexquinquefasciatus (Diptera, Culicidae).

INTRODUCTION: We report the larvicidal activity of two formulations from Amanita muscariaagainst Culex quinquefasciatus, as well as the viability of the aqueous extract after storage. METHODS The larvicidal activity of aqueous extract and powder from A. muscaria, and the viability of the aqueous extract after storage, were evaluated. RESULTS The aqueous extract caused larval deaths, which varied from 16.4% to 88.4%. The efficiency of the powder varied from 29.2% to 82.8%. Storage did not interfere with the larvicidal efficiency of the aqueous extract of A. muscaria. CONCLUSIONS These results show the potential of A. muscariato control C. quinquefasciatus.

Diversity and associations between Drosophilidae (Diptera) species and Basidiomycetes in a Neotropical forest.

Drosophilidae is one of the most representative families of insects that occurs in fungal fruiting bodies of Basidiomycetes; however, the diversity and community structure of mycophagous Drosophilidae in the Neotropical region is poorly known. The aims of the present study were to describe the diversity of mycophagous Drosophilidae and to investigate its colonization of fungal hosts in a forest of southern Brazil. From 120 fungal samples (patches of mushrooms) of 17 Basidiomycetes genera, flies were recorded emerging from 70 samples and collected in adult stages of 25 fungal samples, for a total of 4897 drosophilids belonging to 31 species and 5 genera. Drosophila Fallén was the most species-rich genus, whereas Hirtodrosophila Duda was the dominant genus. Studies performed in the Holarctic region indicate that mycophagous drosophilid have generalist habits; however, our results showed that most drosophilids use fewer than two fungal hosts, and most species of Hirtodrosophila and Leucophenga were restricted to abundant fungal species, suggesting a specialization for these resources. The most specialized fauna emerged from Auricularia, which was the most frequent fungal genus in our collection, and this result supports the assumption that specialization depends on the availability of fungal resources over time.

Evaluation of growth and production of Pleurotus sp. in sterilized substrates / Avaliação do crescimento e da produção de Pleurotus sp. em substratos esterilizados

The gender Pleurotus is also known as oyster mushroom, shimeji or hiratake. Aiming to select the best substrates to cultivate two species of Pleurotus, this work measured vigor, mycelium growth (cm.day-1), fresh mass (g), productivity (%) and biological efficiency (%) of P. sajor-caju (PSC96/03) and P. ostreatoroseus (POR01/06) cultivated in the following substrates: sugarcane bagasse, elephant grass, waste of castor oil plant and pasteurized rice straw. Fungal cultures were recovered in culture medium CDA. For the evaluation of mycelium growth, moist substrates were put into a closed assay tube with sterilized aluminum paper. Then, they were inoculated in 10 mm culture dishes and taken to the incubator at 26 ± 2C. Mycelium vigor was measured with grades from 1 to 3 according to density. For axenic cultivation, substrates were placed into 250 g flasks of substrate and autoclaved twice at 121C (1 atm) for 60 minutes, and then inoculated with 3% of spawn. The lineage P. sajor-caju (PSC96/03) showed higher growth rates in relation to P. ostreatoroseus (POR01/06). Substrates showing lower C/N ratio provided more mycelium vigor. Castor oil plant waste based-substrate showed good perspectives to growing P. sajor-caju (PSC96/03).

O gênero Pleurotus é conhecido como cogumelo ostra, shimeji ou hiratake. Neste trabalho, com a finalidade de selecionar substratos para o cultivo de duas espécies de Pleurotus, foram avaliados vigor, crescimento micelial (cm.dia-1), massa fresca (g), produtividade (%) e eficiência biológica (%) de P. sajor-caju (PSC96/03) e P. ostreatoroseus (POR01/06) cultivados nos substratos: bagaço de cana-de-açúcar, capim-elefante, resíduos da cultura da mamona e palha de arroz esterilizados. As culturas fúngicas foram recuperadas em meio de cultura CDA. Para avaliar o crescimento micelial, os substratos úmidos foram acondicionados em tubos de ensaio e fechados com papel alumínio esterilizados. Depois, foram inoculados com discos de cultura de 10 mm de diâmetro e incubados em estufa a 26 ± 2C. O vigor do micélio foi mensurado por meio de notas de 1 a 3, conforme adensamento. Para o cultivo axênico, os substratos foram colocados em frascos de 250 g de substrato e autoclavados duas vezes a 121C (1 atm) por 60 minutos, posteriormente inoculados com 3% de spawn. Ao serem analisadas, a linhagem P. sajor-caju (PSC96/03) apresentou maior velocidade de crescimento que a P. ostreatoroseus (POR01/06), os substratos com menor relação C/N propiciaram maior vigor de micélio e o substrato à base de resíduos da cultura da mamona apresentou perspectivas para o cultivo de P. sajor-caju (PSC96/03).

Caracterização microbiológica e sorológica de linhagens de Escherichia coli, isolada de carne moída comercializada em Pelotas, RS / Microbiological characterization and sorologica of lineages of Escherichia coli, isolated of meat traded in Pelotas, RS city

Neste trabalho, objetivou-se o isolamento e a identificação de Escherichia coli em carne moída de primeira e de segunda qualidade comercializada em Pelotas, totalizando 33 amostras de cada categoria. As amostras foram coletadas em casas especializadas na venda de carnes e processadas no Laboratório de Microbiologia do Instituto de Biologia da UFPel. Das 66 amostras analisadas, 48 (72,73 por cento) encontravam-se contaminadas com E. coli. Os resultados nos indicam que o alimento analisado apresentou contaminação por E. coli. Contaminação maior se deu na carne moída de primeira qualidade, a qual apresentou 48 isolados positivos, enquanto que a de segunda qualidade foram 30 isolados. Um total de 46 isolados foram submetidos à sorologia, onde 34 foram confirmadas como EPEC, sendo 16, 17, 01 como EPEC PoliA, B e C, respectivamente, e outros 02 isolados como 0157 e os restantes, (10 isolados) não soroaglutinaram com nenhum dos anti-soros testados. Dos 78 isolados, apenas 05 apresentaram capacidade hemolítica e a maioria das cepas testadas apresentou um grau elevado de sensibilidade á gentamicina 98,7 por cento (77 isolados), enquanto que 72 por cento (56 isolados) apresentou resistência à ampicilina.

In this work, it was aimed at the isolation and the identification of Escherichia coli in worn out meat of first and second quality marketed in Pelotas, totaling 33 samples of each category. The samples were collected specialized homes in the sale of meats and processed at the Laboratory of Microbiology of the Institute of Biology of UFPel. Of the 66 analyzed samples, 48 (72,73%) they were polluted with E. coli. The results indicate us that the analyzed food presented high level of contamination for E. coli. Larger contamination felt in the worn out meat of first quality, which presented 48 positive isolations, while the one of second quality was 30 isolations. A total of 46 isolated was submitted to the serology, where 34 were confirmed like EPEC, being 16, 17, 01 as EPEC Polished, B and C respectively, and other 02 isolated as 0157, and the remaining (10 isolated) no soro aglutinaram with none of the tested antiserums. Of the 78 only isolated 05 presented capacity hemolytic, and most of the tested stumps presented a high degree of sensibility the gentamicina 98,7% (77 isolated), while 72% (56 isolated) it presented resistance the ampicilína.

Caracterização microbiológica e sorológica de linhagens de Escherichia coli, isolada de carne moída comercializada em Pelotas, RS / Microbiological characterization and sorologica of lineages of Escherichia coli, isolated of meat traded in Pelotas, RS city

Neste trabalho, objetivou-se o isolamento e a identificação de Escherichia coli em carne moída de primeira e de segunda qualidade comercializada em Pelotas, totalizando 33 amostras de cada categoria. As amostras foram coletadas em casas especializadas na venda de carnes e processadas no Laboratório de Microbiologia do Instituto de Biologia da UFPel. Das 66 amostras analisadas, 48 (72,73 por cento) encontravam-se contaminadas com E. coli. Os resultados nos indicam que o alimento analisado apresentou contaminação por E. coli. Contaminação maior se deu na carne moída de primeira qualidade, a qual apresentou 48 isolados positivos, enquanto que a de segunda qualidade foram 30 isolados. Um total de 46 isolados foram submetidos à sorologia, onde 34 foram confirmadas como EPEC, sendo 16, 17, 01 como EPEC PoliA, B e C, respectivamente, e outros 02 isolados como 0157 e os restantes, (10 isolados) não soroaglutinaram com nenhum dos anti-soros testados. Dos 78 isolados, apenas 05 apresentaram capacidade hemolítica e a maioria das cepas testadas apresentou um grau elevado de sensibilidade á gentamicina 98,7 por cento (77 isolados), enquanto que 72 por cento (56 isolados) apresentou resistência à ampicilina.