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Application of pulp and peels of ariá (Calathea allouia) in dehydrated soups formulations
No full textISOLAMENTO, CARACCTERIZAÇÃO E AMPLIFICAÇÃO INTERESPECÍFICA DE MARCADORES MICROSSATÉLITES PARA Pseudoplatystoma tigrinum (SILURIFORMES: PIMELODIDAE)
No full textO Manejo das Caiçaras Indígenas: Uma prática agropecuária no Lavrado de Roraima, Amazônia brasileira
Get PDFNew records of mesoclemmys raniceps (Testudines, chelidae) for the states of amazonas, pará and Rondônia, north Brazil, including the Tocantins basin
Get PDFLipidomic profiles from seed oil of Carapa guianensis Aubl. and Carapa vasquezii Kenfack and implications for the control of phytopathogenic fungi
No full textThe oils of species from the genus Carapa are widely used for the control of diseases and the production of cosmetics. In this study, the lipidomic profiles of the oil from Carapa guianensis and C. vasquezii seed were characterized with an emphasis on the major compounds and their synergistic implications for the inhibition of phytopathogenic fungi (Aspergillus flavus, A. niger and Fusarium oxysporum). C. guianensis oil contained 42.3% methyl oleate, 26.0% methyl palmitate and 12.5% oleic acid as their principal compounds. C. vasquezii oil contained 38.6% methyl oleate, 20.5% methyl palmitate and 14.5% oleic acid. The presence of myristic acid compounds (0.1%), methyl 11-eicosanoate (0.1%), scalene (0.1%) and β-sitosterol (0.1%) was the special feature of the oil from C. guianensis. On the other hand, arachidic acid (0.15%) was found specifically in C. vasquezii. The C. vasquezii and C. guianensis oils showed a deleterious effect against the three phytopathogenic fungi, with IC 50 values ranging from 6.5 to 47.8 μL mL−1 and 19.7 to 71.2 μL mL−1, respectively. The oils from Carapa seeds had inhibitory effects on the conidial germination of A. flavus, A. niger and F. oxysporum. The oils from C. guianensis and C. vasquezii had similar lipidomic profiles for the major compounds, but C. vasquezii oil had a greater per-centage of saturated fatty acids when compared to C. guianensis and its inhibition of A. flavus, A. niger and F. oxysporum suggested synergistic actions of the substances in the control of phytopathogenic fungi. © 201
Critical wind speeds suggest wind could be an important disturbance agent in Amazonian forests
No full textFlood pulse regulation of bacterioplankton community composition in an Amazonian floodplain lake
No full textUnderstanding spatial and temporal dynamics of microbial communities is a central challenge in microbial ecology since microorganisms play a key role in ecosystem functioning and biogeochemical cycles. Amazonian aquatic systems comprise a dynamic mosaic of heterogeneous habits but are understudied and there is limited information about the mechanisms that shape bacterial community composition (BCC). There is a consensus that environmental selection (species sorting) and dispersal processes (source–sink dynamics) act in concert to shape the composition of these communities, but the relative importance of each mechanism may vary dramatically through time and between systems. Applying 16S rRNA gene amplicon high-throughput sequencing, we studied factors and processes that modulate BCC in an Amazonian floodplain lake and used source-tracking models to trace the main dispersal sources of microorganisms in the whole floodplain system during a full hydrological cycle. Our source-tracking models indicated that dispersal processes were predominant, explaining most of the BCC variability throughout the study period. We observed more sources contributing to the sink community during the falling water than rising water period, when contributions from the Solimões River dominated. There was a clear seasonal pattern in BCC, closely related to environmental variables, suggesting that the successful establishment of dispersing bacteria also depends on environmental filtering that is linked to water flow. In summary, source–sink dynamics and species sorting were strongly affected by water exchange and connectivity with the main river that varied throughout the flood pulse cycle. Our results demonstrated the influence of lateral transport and temporal dynamics on BCC in Amazonian floodplain lakes that could ultimately impact regional carbon budgets and biogeochemical cycles. © 2018 John Wiley & Sons Lt
Volatile monoterpene ‘fingerprints’ of resinous Protium tree species in the Amazon rainforest
Get PDFVolatile terpenoid resins represent a diverse group of plant defense chemicals involved in defense against herbivory, abiotic stress, and communication. However, their composition in tropical forests remains poorly characterized. As a part of tree identification, the ‘smell’ of damaged trunks is widely used, but is highly subjective. Here, we analyzed trunk volatile monoterpene emissions from 15 species of the genus Protium in the central Amazon. By normalizing the abundances of 28 monoterpenes, 9 monoterpene ‘fingerprint’ patterns emerged, characterized by a distinct dominant monoterpene. While 4 of the ‘fingerprint’ patterns were composed of multiple species, 5 were composed of a single species. Moreover, among individuals of the same species, 6 species had a single ‘fingerprint’ pattern, while 9 species had two or more ‘fingerprint’ patterns among individuals. A comparison of ‘fingerprints’ between 2015 and 2017 from 15 individuals generally showed excellent agreement, demonstrating a strong dependence on species identity, but not time of collection. The results are consistent with a previous study that found multiple divergent copies of monoterpene synthase enzymes in Protium. We conclude that the monoterpene ‘fingerprint’ database has important implications for constraining Protium species identification and phylogenetic relationships and enhancing understanding of physiological and ecological functions of resins and their potential commercial applications. © 2019 The Author
