Assuntos
COVID-19/epidemiologia , Brasil , COVID-19/virologia , Humanos , Estudos Soroepidemiológicos , Fatores de TempoRESUMO
Urbanization represents a profound shift in human behaviour, and has considerable cultural and health-associated consequences1,2. Here, we investigate chemical and microbial characteristics of houses and their human occupants across an urbanization gradient in the Amazon rainforest, from a remote Peruvian Amerindian village to the Brazilian city of Manaus. Urbanization was found to be associated with reduced microbial outdoor exposure, increased contact with housing materials, antimicrobials and cleaning products, and increased exposure to chemical diversity. The degree of urbanization correlated with changes in the composition of house bacterial and microeukaryotic communities, increased house and skin fungal diversity, and an increase in the relative abundance of human skin-associated fungi and bacteria in houses. Overall, our results indicate that urbanization has large-scale effects on chemical and microbial exposures and on the human microbiota.
Assuntos
Biodiversidade , Exposição Ambiental/análise , Produtos Domésticos/análise , Urbanização , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Microbiologia Ambiental , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Habitação , Humanos , Microbiota , Floresta Úmida , América do SulRESUMO
The Amerindian yam (Dioscorea trifida) is a food plant native to the Amazon region. Several local varieties are cultivated by traditional family farmers for consumption and local trade. However, socioeconomic processes may be causing species genetic erosion. Knowledge about species sexual reproduction is essential for its conservation and genetic improvement. The objective of this study was to observe the floral phenology, to assess the germination and dormancy of seeds, to conduct controlled pollinations and to select hybrid plants of D. trifida with agronomic potential. Seed dormancy was confirmed and was broken by after-ripening at 28 oC and 80% RH. We carried out controlled pollinations between local landraces and cultivated the resulting hybrid plants in the field. The new genotypes showed high phenotypic variability and tubers with new characteristics, which permitted the selection of genotypes with agronomic potential for further studies. The results contribute to the conservation of agrobiodiversity and genetic improvement for added value of Amazonian native food plants. (AU)
