The search for novel natural molecules with insecticide potential has become a necessity more than an alternative. Understanding the mode of action of candidate molecules is a crucial step towards the development of new bioinsecticides. The present study focused on the neurotoxicity of Canavalia ensiformis urease, a natural insecticide, in cockroaches and revealed interferences on the cholinergic, octopaminergic and GABA-ergic pathways as part of its entomotoxic mode of action.

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O ensino de entomologia no ensino básico tem sido um grande desafio para os educadores. O uso do livro didático tem sido a ferramenta mais utilizada, resultando em pouca aderência dos alunos às atividades propostas em sala de aula. Outras ferramentas, como os insetários, são bastante exploradas, porém a necessidade de manutenção constante e impossibilidade de manuseio por parte dos alunos deixa evidente a necessidade de busca por alternativas mais interessantes que proporcionem um melhor aprendizado para os alunos. O trabalho traz o passo-a-passo para a elaboração blocos com insetos incrustados em resina, bem como sua aplicação em sala de aula.

The study of Agaricomycetes in the Brazilian Pampa Biome is still incipient, but it is very necessary for the valorization and preservation activities in this area. In terms of fungal diversity, it is the least studied Brazilian biome, with only 84 species already described for the site, despite the great diversity of fauna and flora that this biome presents. The objective of this work is to know more about the mycodiversity of this biome, contributing to a better understanding of the distribution and ecology of the Agaricales. The collections were made following the usual methodology for Agaricales (Basidiomycota). Thus, specimens were collected for studies to identification to species level by macro- and microscopic characters. Descriptions of seven species collected in the rural region surrounding the city of São Gabriel, state of Rio Grande do Sul, Brazil are presented, which are cited for the first time for the Pampa Biome, namely: Macrolepiota mastoidea, Protostropharia alcis ssp. austrobrasiliensis, Trogia buccinalis, Crepidotus euterpicola, Entoloma depluens, Lepiota subincarnata and Neopaxillus echinospermus. These new citations reinforce the importance of studies on the biodiversity of the Pampa biome for its preservation.

Mushrooms are cultivable on various plant substrates and the yerba mate residue may be one of the most promising, especially if domestic cultivation techniques are developed. As a large producer and consumer of yerba mate, southern Brazil also presents a large production of this residue. In this sense, this work aimed to test the cultivation of Pleurotus ostreatoroseus on yerba mate residue, seeking a technique for its domestic cultivation. Three substrates were prepared: a) partially decomposed yerba mate; b) recently discarded yerba mate; c) yerba mate recently discarded and added with eucalyptus sawdust. Cultivation of P. ostreatoroseus in yerba mate just after disposal and partially decomposed proved to be unviable, with good mycelial colonization of the substrate, but without basidioma production. In cultivation with sawdust, all concentrations tested showed the formation of primordia, with 70% of sawdust, being the first to form primordia and having the largest basidiome in diameter. It is believed that aeration is an important factor for mycelial and basidiome development in P. ostreatoroseus, contrary to what has already been mentioned for P. djamor, contributing to the differentiation of both species in cultivation situations. The mycelium of the species growing on yerba mate residue was able to reduce the inoculum of pathogenic fungi, indicating that it is an adequate practice for the treatment of the final residue. Thus, the yerba mate residue added with sawdust proved to be a possible substrate for the cultivation of P. ostreatoroseus, in addition to eliminating pathogenic fungi from plants. Keywords: Cultivation; Alternative substrates; Shimeji; Mycelial growth.

O cultivo de cogumelos do grupo Shimeiji (Pleurotus spp.) faz uso dos mais diversos substratos. No Brasil o bambu ainda não foi testado. O produtor sempre precisa comprar nova “semente” para inoculação num novo ciclo, encarecendo o processo, além de usar recipientes de plástico, contaminando o produto final. O bambu tem sido amplamente plantado em pequenas propriedades rurais, estando disponível para outros usos, além de material construtivo. Procurando resolver estes problemas, testou-se uma formulação à base de serragem de Eucalyptus introduzida em bambu. Colmos de cerca de 30 cm foram preparados com a inoculação direta de serragem de Eucalyptus. No teste inicial com bambu os cogumelos foram formados após 48 dias de inoculação, o que reduziu o tempo de produção pela metade, demonstrando ser viável o seu uso. Os novos plantios resultaram em sucesso na colonização do substrato, indicando viabilidade de novas bateladas de produção usando o mesmo colmo sem necessidade de nova semente.

Bird-fungi associations are ecologically important, and the species of these groups that occur in the Pampa biome region have different characteristics. The Shiny Cowbirds (Molothrus bonariensis – Icteridae) is a ground foraging bird that cohabits vegetation of grasslands. Some mushrooms of this biome have considerably large and edible basidiomes, such as species of genus Macrolepiota (Agaricaceae). Therefore, the objective of this study was to contribute to the first description of mycophagy for the Pampa biome, including the species Molothrus bonariensis and Macrolepiota bonariensis. Data were submitted to a test of variance ANOVA and Tukey test at a 5% significance level.  For the quantitative multivariate data, the test of Kiviat was elaborated. The test of Schumacher and Eschmeyer was used to determine the degree of interaction of the birds with the mushrooms. 60 hours of observations were realized with a flock of bird containing approximately 76 individuals in the study area. 30 fresh scat samples and 10 mushrooms that showed pecks signals were collected from the area georeferenced. Microscopic analysis of scat of birds revealed basidiospores of mushroom. For the record of foraging events, the mycophagy of birds was higher in zones with more occurrence of mushrooms. The results assist in better understand this important mycophagy interaction between the Shiny Cowbird and the mushroom M. bonaerensis. The study confirms that bird-fungal mycophagy associations are more widespread than previously thought.

Foi realizada um levantamento bibliográfico, analisando-se 7 artigos e 1 dissertação de mestrado realizados entre 1915 e 2018, que citam a ocorrência de Myxomycetes (Protista, Amebozoa) no Rio Grande do Sul. Um total de 110 espécies é citado para o estado, sendo a ordem Physarales, a mais representativa. Além disso, as áreas de Mata Atlântica, embora muito menores que as áreas abrangidas pelo Bioma Pampa, concentram o maior número de espécies, com 81 espécies do total que ocorre no estado.