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Abstract Plants that produce allelopathic compounds against weeds have emerged as a potential solution for the development of ecologically correct bioherbicides. Talinum triangulare is noteworthy in this regard, as its phytochemical composition encompasses flavonoids, alkaloids and other metabolites that can be used to develop inhibitory weed growth solutions. Lactuca sativa (lettuce) has been widely applied as a bioindicator species for bioherbicides and several chemicals, animal waste, water and soil quality, and atmospheric contamination, among others. In this context, this study aimed to assess the potential allelopathic effect of aqueous T. triangulare extracts on the development of L. sativa seedlings. A completely randomized design employing a 2x4 factorial scheme (shoot and root extracts) x the concentration of each extract (0, 2.5, 5, 7.5%) was applied, comprising four replications. Lactuca sativa seeds were sown on germitest papers soaked with the extracts in a germination chamber at 20°C. Physiological seed evaluations comprising the germination test, where normal and abnormal seedlings are counted on the seventh day after sowing, first normal seedling counts on the fourth day after sowing, and seedling and root length measurements. At the end of the germination test, L. sativa seedlings were separated for morphoanatomical characterizations and chlorophyll a fluorescence analyses. The T. triangulare extracts significantly influenced L. sativa root growth, with shoot extract exposure leading to more abnormal plants and lower root lengths at increasing concentrations and compared to the root extract. Root extract exposure led to evident cellular changes and lower non-photochemical quenching and unregulated dissipation quantum yields at a 5% exposure dose compared to shoot extract exposure. These findings suggest that both aqueous T. triangulare root and shoot extracts from 5% exposure doses exhibit high potential as bioherbicides, acting directly on plant structure, anatomy, quality, size and physiology.

Abstract The Brazilian Midwest is responsible for 54.3% of the country’s soybean production. Adequate storage technologies are essential to maintain physical, physiological, and sanitary seed qualities while also minimizing deterioration processes and consequent germination and vigor declines. In this context, the aim of the present study was to evaluate the physiological potential and physical qualities of soybean seeds stored under different environmental conditions and storage bag depths. Assays were carried out in September 2021 employing Foco 74i77 RSF IPRO cultivar seeds stored from April to August 2021 under three conditions, as follows: chilled at an average temperature of ≤20 °C, at an average temperature of ≤25 °C using a with blanket, and in without blanket warehouse structure at an average temperature of ≥25 °C with no with blanket. A completely randomized 3x3 factorial experimental design was applied, comprising three storage environments and three bag positions (top, middle, and bottom), with three replication each. Physical, physiological, and biochemical tests were performed on the stored seeds. The findings indicate better seed preservation in the chilled environment or when using a with blanket, with significant differences noted for seeds stored the middle of the storage bag. Therefore, soybean seed storage in a chilled environment or using a with blanket aids in slowing down the seed deterioration processes, preserving physiological quality and vigor compared to a conventional storage environment. Additionally, the quality of soybean seeds stored under these conditions in the middle of storage bags is maintained.

The Cerrado has wide plant diversity, including orchids. These plants need symbiosis with fungi for their germination to occur in the wild. In vitro or asbiotic cultivation is an alternative for the production of seedlings of this species. This diversity of orchids makes it much appreciated as pot plants, landscaping, with high commercial value. The objective of this work was to carry out the study for the development of a protocol for the germination and in vitro development of orchids. The experiment was carried out at the LABIOTEC Biotechnology Laboratory of the Federal Institute Goiano Campus Urutaí-GO. Catasetum sp native capsules from Goiás State, containing mature seeds were collected and disinfected in 50% sodium hypochlorite solution for 30 minutes and in laminar flow were washed four times in distilled and autoclaved water. They were then seeded in vitro in 258 mL glass vials containing 30 mL of MS medium enriched with vitamins and 0.0 Tryptone; 1.0; 2.0 and 3.0 g L-1. The pH of the medium was adjusted to 5.2 ± 0.1. The average time for germination and development of the protocorms varied from 3 to 7 days after sowing for the species under study. The dosage of 2.0 g L-1 is efficient for the development and maintenance of in vitro Catasetum protocorms up to 333 days. There was no development of shoot of Catasetum seedlings in any of the evaluated treatments. It was observed that the 3.0 g L-1 Tryptone dosage presented higher rates of fungal and bacterial contamination and oxidation

The effect of water replenishment on the physiological quality and seed uniformity of Napoli and Contender bean cultivars harvested in May 2015 was studied; Contender and Japanese Yellow collected in the 2016 and 2017 harvests in the experimental area of the State University of Goiás - UEG. The experiment was installed in the Laboratory of Vegetable Production of UEG-GO. The sowing was done using four replicates of 50 seeds, distributed among three sheets of germitest paper, moistened with demineralized water. The rolls were taken to the germinator regulated at 25ºC. The experimental design was completely randomized with different cultivars, collection times and water replenishment, with 4 replicates. The germination indexes were evaluated; speed of germination; hard seeds; dormant and dead; index of seedlings with small defect; with secondary infection and intact seedlings. The physiological quality of the seeds was evaluated by means of the germination and vigor test and the results in percentage and the statistic using software R. Seeds from the different water replaces, cultivars and production times presented as promising for the cultivation in Ipameri-GO.

Monocristais de ítria (Y2O3) são importantes materiais hospedeiros para lasers. Entretanto, seu elevado ponto de fusão (2450 ºC) dificulta o processo de crescimento de monocristais. Uma alternativa para a obtenção de ítria policristalina com propriedades similares às dos monocristais é a fabricação de cerâmicas transparentes. Desta forma, este trabalho teve o propósito de desenvolver uma metodologia para fabricar cerâmicas transparentes de ítria, utilizando-se um forno de indução eletromagnética que permite o uso controlado de atmosferas inertes ou redutoras e pode atingir temperaturas próximas a 2000 ºC, com taxas de aquecimento maiores que 100 ºC/min. Os pós-precursores foram preparados por meio de reação do estado sólido usando 3% em mol de ZrO2 como aditivo. As amostras foram conformadas em discos com 12 mm de diâmetro e 1 mm de espessura sob uma pressão uniaxial de 50 MPa e isostática de 350 MPa. Em seguida, foram sinterizadas a 1800 e 1900 ºC com tempos de sinterização de 1 e 5 h. Difração de raios X e microscopia eletrônica de varredura foram usadas na caracterização estrutural e microestrutural das amostras e sua transmissividade ótica foi medida por meio de espectrofotometria. Através da sinterização em forno de indução foi possível obter cerâmicas com até 60 % de transmissão em linha na região de 800 nm em tempos de sinterização menores que os descritos na literatura.

This study aimed to describe anatomical characteristics of wood known as 'louros' from the Brazilian Amazon. The species is also known in Portuguese as preciosa, louro preto, louro pimenta, louro rosa, itauba, itauba amarela, louro branco and louro vermelho. Wood samples were collected in the extractivist communities of Paraíso and Arimum, located in the Verde Para Sempre Extractivist Reserve in Pará State, Brazil. All evaluated wood had diffuse porosity, simple perforate plate, alternate intervessel pits and non-storied rays. The anatomical characteristics indicated that louro branco had lower average ray frequency values (1.23), while preciosa, itauba and itauba amarela had higher mean ray frequency (6.70, 6.43 and 6.60), respectively. Samples of louro vermelho and louro branco had higher values for ray height (1994.36 and 5579.81) and width (511.21 and 506.40). Regarding vessel dimensions and frequency, itauba and itauba amarela had higher vessel frequency (11.43 and 11.83). Overall, strong uniformity of wood structure was observed at macroscopic and microscopic levels in the evaluated species. However, there were some slight differences. The anatomical characteristics, effective for discrimination, were axial parenchyma type, presence of septate fibres, type and grouping of vessels, presence of oil cells and starch. [ABSTRACT FROM AUTHOR]

The objective of this study is to verify the contribution of the spectral bands from the new WorldView-2 satellite for the extraction of urban targets aiming a detailed mapping from the city of São Luis, at the coastal zone of Maranhão State, Brazil. This satellite system has 3 bands in the visible portion of the spectrum and also the following 4 new bands: Coastal (400-450 nm), Yellow (585- 625 nm), Red Edge (705-745 nm), and Near Infrared 2 (860-1040 nm). As for the methodology used, initially a fusion was made among the panchromatic and the multispectral bands, combining the spectral information of the multispectral bands with the geometric information of the panchromatic band. Following the ortho-rectification of the dataset was done, using ground control points (GCPs) obtained during field survey. The classification reached high values of Kappa indices. The use of the new bands Red Edge and Near Infrared 2, allowed the improvement of discriminations at tidal flats, mangrove and other vegetation types. The Yellow band improved the discrimination of bare soils – very important information for urban planning – and ceramic roofs. The Coastal band allowed to map the tidal channels which cross the urban area of São Luis, a typical feature of this coastal area. The functionalities of software GEODMA used, allowed an efficient attribute selection which improved the land cover classification from the test sites. The new WorldView-2 bands permit the identification and extraction of the features mentioned, because these bands are positioned at important parts of the electromagnetic spectrum, such as band Red Edge, which strongly improves the discrimination of vegetation conditions. Combining both higher spatial and spectral resolutions, WorldView-2 data allows an improvement on the discrimination of physical characteristics of the targets of interest, thus permitting a higher precision of land use/land cover maps, contributing to urban planning. The test sites of this study represent the main problem areas involving the city of São Luis and the entire region of the Maranhão Island.

Taking into account the importance of mangrove environments for the biodiversity of coastal areas, the objective of this paper is to classify the different types of irregular human occupation on the areas of mangrove vegetation in São Luis, capital of Maranhão State, Brazil, considering the OBIA (Object-based Image Analysis) approach with WorldView-2 satellite data and using InterIMAGE, a free image analysis software. A methodology for the study of the area covered by mangroves at the northern portion of the city was proposed to identify the main targets of this area, such as: marsh areas (known locally as Apicum), mangrove forests, tidal channels, blockhouses (irregular constructions), embankments, paved streets and different condominiums. Initially a databank including information on the main types of occupation and environments was established for the area under study. An image fusion (multispectral bands with panchromatic band) was done, to improve the information content of WorldView-2 data. Following an ortho-rectification was made with the dataset used, in order to compare with cartographical data from the municipality, using Ground Control Points (GCPs) collected during field survey. Using the data mining software GEODMA, a series of attributes which characterize the targets of interest was established. Afterwards the classes were structured, a knowledge model was created and the classification performed. The OBIA approach eased mapping of such sensitive areas, showing the irregular occupations and embankments of mangrove forests, reducing its area and damaging the marine biodiversity.