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Arbuscular mycorrhizal fungi (AMF) have been used to promote numerous benefits to plants. In this study, we evaluated the symbiosis between AMF species (Rhizophagus clarus, Claroideoglomus etunicatum) and Piper nigrum L. ‘Bragantina’. Volatile compounds, lipoxygenase (LOX) and phenylalanine ammonia-lyase (PAL) activities, and total phenolic content were monitored from 1 to 60 days post-inoculation (dpi). Hyphae, arbuscles, and vesicles were observed during the root colonization. In the leaves, AMF induced an increase of sesquiterpene hydrocarbons (54.0%–79.0%) and a decrease of oxygenated sesquiterpenes (41.3%–14.5%) at 7 dpi and 60 dpi (41.8%–21.5%), respectively. Cubenol, the main volatile compound of leaves, showed a significant decrease at 7 dpi (21.5%–0.28%) and 45 dpi (20.4%–18.42%). β-caryophyllene, the major volatile compound of the roots, displayed a significant reduction at 45 dpi (30.0%–20.0%). LOX increased in the roots at 21, 30, and 60 dpi. PAL was higher in leaves during all periods, except at 60 dpi, and increased at 21 and 45 dpi in the roots. The total phenolic content showed a significant increase only in the roots at 30 dpi. The results suggested that AMF provided changes in the secondary metabolism of P. nigrum, inducing its resistance.

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To elucidate defense mechanisms of Piper nigrum against fusariosis, an experiment based on co-inoculation of arbuscular mycorrhizal fungi (AMF) and Fusarium solani f. sp. piperis was performed. Variations in secondary metabolism in plants infected with F. solani f. sp. piperis (FUS) and co-inoculated with AMFs and F. solani (AMF + FUS) were monitored at 7- and 21-days post inoculations (dpi). The pathogen induced a decrease in oxygenated sesquiterpenes (82.0–77.4%), and changes in the concentrations of the main compounds, α-muurolene, α-muurolol, and 2E-hexenal in the leaves. It was observed that the concentration of 2E-hexenal decreased at 7 dpi, α-muurolene decreased at 21 dpi, and α-muurolol increased at 21 dpi. There was a prevalence of sesquiterpene and monoterpene hydrocarbons in the roots, such as β-caryophyllene, δ-elemene, and limonene. The infection and co-inoculation induced greater production of phenolics in the roots at 7 dpi. The enzymatic activity of phenylalanine ammonia-lyase decreased in the leaves at 21 dpi and in the roots on both days, while the lipoxygenase activity decreased only in the roots at 21 dpi. The results demonstrated that co-inoculation with AMFs and F. solani induces changes in the defense metabolism of P. nigrum, but it is not efficient in the biocontrol of fusariosis during the evaluated period.

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The theoretical explanation of biological concepts, associated with the use of teaching games andmodels, intensify the comprehension and increase students interest, stimulating them to participateactively on the teaching-learning process. The sta of dissemination from Centro de BiotecnologiaMolecular Estrutural (CBME), in partnership with the Centro de Divulgac~ao Cientca e Cultural(CDCC), presents, in this work, a new educational resource denoted: Protein Synthesis Game. Theapproach of the game involves the cytological aspects of protein synthesis, directed to high schoolstudents. Students are presented to day-by-day facts related to the function of a given protein in thehuman body. Such task leads players to the goal of solving out a problem through synthesizing aspecied protein. The game comprises: (1) a board illustrated with the transversal section of animalcell, with its main structures and organelles and sequences of hypothetical genes; (2) cards with thedescription of steps and other structures required for protein synthesis in eukaryotic cells; (3) piecesrepresenting nucleotides, polynucleotides, ribosome, amino acids, and polypeptide chains. In order toplay the game, students take cards that sequentially permit them to acquire the necessary pieces forproduction of the protein described in each objective. Players must move the pieces on the board andsimulate the steps of protein synthesis. The dynamic of the game allows students to easily comprehendprocesses of transcription and translation. This game was presented to dierent groups of high schoolteachers and students. Their judgments have been heard and indicated points to be improved, whichhelped us with the game development. Furthermore, the opinions colleted were always favorable forthe application of this game as a teaching resource in classrooms.