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Background: Animal odor, is one of the most common aroma defects described in the honey odor aroma wheel. It comprises two secondary descriptors: 'fecal' and 'cowshed'. However, the compounds responsible for these honey defects have not been fully identified. In this context, the aim of this work was to identify the compounds responsible for the aromatic defect 'fecal' in Uruguayan honeys by means of gas chromatography coupled to olfactometry (GC–O). Results: Samples of honey described by beekeepers as having fecal aroma were analyzed by GC‐O and gas chromatography coupled to mass spectrometry (GC–MS). Through GC–O, it was possible to establish the region of the chromatogram corresponding to the fecal descriptor, while the GC–MS analysis allowed to identify indole as the compound responsible for the fecal descriptor. The content of indole in the analyzed samples ranged between 132 and 414 μg kg−1. The melissopalynological analysis indicated the presence of Scutia buxifolia ('quebracho' or 'coronilla') pollen in all samples studied. The volatile profile of Scutia buxifolia flowers was evaluated during the full day, enabling the identification of indole as one of its components. The detection threshold value for indole in honey was experimentally determined as 64 μg kg−1 of honey, a value lower than the concentration found in the evaluated samples. Conclusion: Results from the study allowed the identification of indole as the compound responsible for the 'fecal' aroma defect in Scutia buxifolia honeys. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Bees (Family Apidae) hold a key role as pollinators in a wide range of angiosperm communities. South America suffered strong modifications during the last decade due to increasing anthropic activities and the expansion of agricultural areas, particularly the boom of soybean. The goal of this research was to know the current diversity of bees in South and Low Littoral regions in Uruguay. Specimens were collected in the seasons 2015–2016 and 2016–2017 on natural meadows, cultivated grasslands, soybean fields, among others flowering communities. Collected specimens were classified following taxonomic keys. Forty-five bee species or taxa were distinguished belonging to the subfamilies Megachilinae (11), Apinae (22), Halictinae (7), Colletinae (2), and Andreninae (3). Most taxa were classified up to genus and 14 to species level. Bee diversity was higher for the South region, with traditional agriculture and rangelands, than that of the Low Littoral region where an increasing agricultural land use took place during the last decade, particularly soybean. In addition, this research aimed to study the presence of native bees and the introduced Apis mellifera (Apinae) in a soybean field at four transects located at 0, 50, 100, and 200 m from the crop border in both seasons. Native bee species were only present at 0 and 50 m, pointing to the relevance of natural edge plant communities for their preservation. This is the first survey on native bee diversity in Uruguay to be regarded as a baseline and the setup of conservation strategies. [ABSTRACT FROM AUTHOR]

Regional seismic reflection profiles and well data from the Uruguayan margin were integrated in order to analyse and illustrate its tectonic and stratigraphic evolution. The evolution of the Punta del Este and Pelotas basins is divided into four major phases: pre-rift (Palaeozoic); rift (Jurassic-Early Cretaceous); transition (Barremian-Aptian) and post-rift (Aptian-Present). Each of these phases is characterized by a specific structural configuration and a stratigraphic architecture related to basin type, tectonic elements, sediment supply and base-level changes. During the geological evolution of the Uruguayan continental margin, a NE migration of depocentres occurred. The Cretaceous depocentre is located in the Punta del Este Basin, while the Cenozoic depocentre is located in the Pelotas Basin. [ABSTRACT FROM AUTHOR]

The variability of ectexine sculpture in the pollen of Jaborosa runcinata (Solanaceae) was studied with light and scanning electron microscopy. Three main ectexine variants are recognized: incomplete reticulate, a combination of incomplete reticulate and gemmate-granular, and gemmate-granular. A range of transient conditions were also noted between the two extremes. Apertures vary from a basically triporate-aspidate arrangement to pollen grains which appear to have a rudimentary colpus. The sculptural variability of the ectexine, and a tendency towards a colpus, in J. runcinata are interesting as intraspecific variation does not appear to be common within Solanaceae. [ABSTRACT FROM AUTHOR]