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The variation in light within the environment triggers morphophysiological changes in plants and can lead to distinct responses in sun-exposed or shaded plants to glyphosate. The response of Urochloa genotypes subjected to desiccation with 2160, 1622.4, 1080, 524.4, 273.6, and 0.0 g ha-1 of glyphosate was evaluated in full sun and shade conditions. Cayana grass, mulato II grass, and sabiá grass - hybrids recently launched on the market, in addition to palisade grass and congo grass were evaluated. Under full sun, we achieved control of congo grass using 1080 g ha-1 of glyphosate, while the other grasses required 2160 g ha-1. In the low-light environment, sabiá grass was effectively controlled with 524.4 g ha-1 of glyphosate, but the other grasses needed 273.6 g ha-1. In shading, compared to full sun, the savings with glyphosate were 75 and 76% for the control of congo grass and sabiá grass, respectively, and 87% for palisade grass, mulato II grass and cayana grass. Increasing glyphosate doses leads to a decline in the quantum efficiency of photosystem II and in the electron transport rate, especially in the shade. Urochloa genotypes are more sensitive to glyphosate in the shade, which must be considered when determining the herbicide dose.

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Colonoscopy is the choice procedure to diagnose, screening, and treat the colon and rectum cancer, from early detection of small precancerous lesions (polyps), to confirmation of malign masses. However, the high variability of the organ appearance and the complex shape of both the colon wall and structures of interest make this exploration difficult. Learned visuospatial and perceptual abilities mitigate technical limitations in clinical practice by proper estimation of the intestinal depth. This work introduces a novel methodology to estimate colon depth maps in single frames from monocular colonoscopy videos. The generated depth map is inferred from the shading variation of the colon wall with respect to the light source, as learned from a realistic synthetic database. Briefly, a classic convolutional neural network architecture is trained from scratch to estimate the depth map, improving sharp depth estimations in haustral folds and polyps by a custom loss function that minimizes the estimation error in edges and curvatures. The network was trained by a custom synthetic colonoscopy database herein constructed and released, composed of 248400 frames (47 videos), with depth annotations at the level of pixels. This collection comprehends 5 subsets of videos with progressively higher levels of visual complexity. Evaluation of the depth estimation with the synthetic database reached a threshold accuracy of 95.65%, and a mean-RMSE of 0.451cm, while a qualitative assessment with a real database showed consistent depth estimations, visually evaluated by the expert gastroenterologist coauthoring this paper. Finally, the method achieved competitive performance with respect to another state-of-the-art method using a public synthetic database and comparable results in a set of images with other five state-of-the-art methods. Additionally, three-dimensional reconstructions demonstrated useful approximations of the gastrointestinal tract geometry. Code for reproducing the reported results and the dataset are available at https://github.com/Cimalab-unal/ColonDepthEstimation.

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This investigation aimed to assess the physiological parameters and quality of milk and fresh cheeses produced by cows that were housed in paddocks, either with or without shade, and supplemented with a phytogenic additive. Sixteen crossbred cows were allocated in a 4 × 4 Latin square design, dividing them into paddocks with or without shade, and providing or not providing a phytogenic additive in their feed. This resulted in a total of four treatment groups and sixteen experimental plots, each containing four animals, over four periods of 21 days. Various parameters were examined, including haematology, rectal and skin temperature, respiratory rate, milk yield and composition, serum parameters, and cheese yield and quality. It is worth noting that the temperature and humidity, as measured by a black globe thermometer, did not display significant variations between the different environments and exhibited minimal fluctuations throughout the day. Additionally, the supplementation of the phytogenic additive led to a reduction in haematocrit levels (p = 0.011). Furthermore, the analysis showed that whey obtained from cheese production had a higher fat content when cows were without access to shade (p = 0.005). Notably, there was an interaction between factors in relation to the total dry extract content, which was lower when cows had access to shade and received the additive (p = 0.010). In summary, the provision of a phytogenic additive and the presence or absence of shade did not bring about significant changes in milk production and quality or in the yield and quality of fresh cheese.

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We recently demonstrated that, under elevated [CO2] (eCa), coffee (Coffea arabica L.) plants grown at high light (HL), but not at low light (LL), display higher stomatal conductance (gs) than at ambient [CO2] (aCa). We then hypothesized that the enhanced gs at eCa/HL, if sustained at the long-term, would lead to adjustments in hydraulic architecture. To test this hypothesis, potted plants of coffee were grown in open-top chambers for 12 months under HL or LL (ca. 9 or 1 mol photons m-2 day-1, respectively); these light treatments were combined with two [CO2] levels (ca. 437 or 705 µmol mol-1, respectively). Under eCa/HL, increased gs was closely accompanied by increases in branch and leaf hydraulic conductances, suggesting a coordinated response between liquid- and vapor-phase water flows throughout the plant. Still under HL, eCa also resulted in increased Huber value (sapwood area-to-total leaf area), sapwood area-to-stem diameter, and root mass-to-total leaf area, thus further improving the water supply to the leaves. Our results demonstrate that Ca is a central player in coffee physiology increasing carbon gain through a close association between stomatal function and an improved hydraulic architecture under HL conditions.

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This study aims to evaluate water, land, and nutrient efficiencies in a tropical beef feedlot system by providing artificial shading and considering local conditions and feed cultivation. The study was conducted at the Experimental Feedlot of Embrapa Southeast Livestock in Brazil. Forty-eight Nellore bulls were divided into two groups, with one group having shade (GS) and the other without shade (GWS). The animals' body weights, water intake, and dry matter intake were recorded. The water footprint was calculated using a product-focused assessment, considering water consumed in feed production and animal drinking. The nutrient balance and land footprint were also assessed. To both treatments, the crop scenario with soybean and corn first crop produced in Maringa resulted in the lowest water and land footprint values. Corn was the main contributor to green water consumption. The efficiency in water use for corn decreased between the first and second crops. The water footprint of soybean meal varied between production locations. GWS had slightly higher average blue water consumption than GS. In terms of nutrient balance, the GS treatment exhibited lower nitrogen and phosphorus balance values, indicating higher efficiency in the use of these elements. The provision of artificial shading was found to reduce the water footprint and improve nutrient use efficiency. The location of grain production and the timing of corn planting were identified as key factors influencing water and land footprint values.

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This study aimed to assess the influence of the high biodiversity silvopastoral system (SPSnu) on the microclimate, pasture production, and pasture chemical composition. Microclimate variables and pasture production and chemical composition were measured in pared paddocks under SPSnu and treeless pasture (TLP) in a commercial farm during four seasons in Southern Brazil. SPSnu measurements were subdivided into two areas: around the nuclei (AN) and area inter-nuclei (IN). In the TLP paddocks, we plotted fictitious nuclei with the same areas and distributions of SPSnu, however without trees. For the microclimate measurements, these areas were noted when shaded or unshaded by the nuclei trees. In each season, the microclimate variables air temperature (AT, °C), relative humidity (RH, %), illuminance (Ilu, lux), wind speed (WS, m/s), and soil surface temperature (SST, °C) were measured. In addition, botanical composition (%), pasture production (kg/DM/ ha), and pasture chemical composition were evaluated. The SPSnu provided the lowest values of microclimate variables in all seasons (p < 0.05), except for the relative humidity. Winter had the highest thermal amplitude in the systems. The highest difference between SPSnu and TLP for AT (4.3 °C) and SST (5.2 °C) was measured during the hot seasons (spring and summer). In contrast, during cold seasons (autumn and winter) it observed highest thermal amplitude between SPSnu and TLP. Overall, the highest annual pasture production was observed in the SPSnu (p < 0.05). During the summer, the SPSnu areas showed the highest values of crude protein and dry matter (p < 0.05). During the winter, the TLP showed the lowest values (p < 0.05) of pasture production and dry matter. It was observed that SPSnu improved the microclimate at the pasture level, influencing pasture production and pasture chemical composition. The enhanced microclimate can partially mitigate some of the effects of climate change on pastoral agroecosystems, creating conditions for ecological rehabilitation of ecosystem processes and services. These conditions could be amplified to a biome level through a payment for ecosystem services program.

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Objetivou-se neste trabalho verificar a influência de distintas colorações de malhas de sombreamento sobre a fenologia, biometria e características físico-químicas de Physalis peruviana L em sistema orgânico de produção. O experimento foi realizado na área experimentalda UFFS, campus Laranjeiras do Sul ­PR, no setor de Horticultura. Como material vegetal foram utilizadas mudas de P. peruviana L. produzidas em estufa agrícola da área didática experimental. O delineamento experimental foi em blocos completamente casualizados, em esquema unifatorial, com quatro malhas de sombreamento (azul, preta, vermelha e branca) + testemunha (sem cobertura), com quatro repetições. Para a fenologia não houve influência estatística das colorações de malhas de sombreamento. Plantas com maior altura e menordiâmetro de caule foram verificadas com o uso da malha de sombreamento da coloração azul. Houve alterações sobre a firmeza de frutos, massa com cálice, diâmetro, altura e sólidos solúveis em função da cor da malha de sombreamento. Conclui-se que as malhasde sombreamento de diferentes colorações não interferem na fenologia de P. peruviana, mas alteram ascaracterísticas biométricas e físico-químicas das frutas, sendo a de coloração vermelha a que proporcionou os melhores resultados, não sendo recomendada autilização da malha de coloração azul.(AU)

The objective of this work was to verify the influence of different colors of shading meshes onthe phenology, biometry and physicochemical characteristics of Physalis peruvianain an organic production system. The experiment was carried out in the experimental area of UFFS, campus Laranjeiras do Sul -PR, in the Horticulture sector. As plant material, seedlings of Physalis peruvianaL. produced in an agricultural greenhouse in the experimental teaching area were used. The experimental design was in completely randomized blocks, in a one-factor scheme, with four shading meshes (blue, black, red andwhite) + control (no cover), with four replications. For the phenology there was no statistical influence of the shading mesh colors. Plants with greater height and smaller diameter were verified using the blue color shading mesh. There were changes in fruit firmness, mass with calyx, diameter, height and soluble solids depending on the type of shading. It is concluded in this work that shading nets of different colors do not affect the phenology of the P. peruviana, but they change the biometric and physicochemical characteristics of fruits, with red color being the ones that provide the best results, the use of the blue colored mesh is not recommended.(AU)

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Coffee (Coffea arabica L.) plants have been assorted as highly suitable to growth at elevated [CO2] (eCa), although such suitability is hypothesized to decrease under severe shade. We herein examined how the combination of eCa and contrasting irradiance affects growth and photosynthetic performance. Coffee plants were grown in open-top chambers under relatively high light (HL) or low light (LL) (9 or 1 mol photons m-2 day-1, respectively), and aCa or eCa (437 or 705 µmol mol-1, respectively). Most traits were affected by light and CO2, and by their interaction. Relative to aCa, our main findings were (i) a greater stomatal conductance (gs) (only at HL) with decreased diffusive limitations to photosynthesis, (ii) greater gs during HL-to-LL transitions, whereas gs was unresponsive to the LL-to-HL transitions irrespective of [CO2], (iii) greater leaf nitrogen pools (only at HL) and higher photosynthetic nitrogen-use efficiency irrespective of light, (iv) lack of photosynthetic acclimation, and (v) greater biomass partitioning to roots and earlier branching. In summary, eCa improved plant growth and photosynthetic performance. Our novel and timely findings suggest that coffee plants are highly suited for a changing climate characterized by a progressive elevation of [CO2], especially if the light is nonlimiting.

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Provision of shade reduces radiant heat load on feedlot cattle, thus reducing demand of water and energy for thermoregulation. While the positive effects of shade on animal welfare are widely known, the literature lacks data on the magnitude of its economic impacts. In this study, we propose the concept of novel shade design to prove that a correctly oriented and dimensioned roof structure, which optimizes shade to be displaced within the pens, motivates cattle to seek shade, protect them from short-wave solar radiation, and is resilient to counteract weather adverse conditions. The beneficial outcome is improvement in animal welfare and productive performance, as well as increments on financial return and sustainability. To attest these benefits, eight hundred B. indicus × Bos taurus bulls were randomly assigned in pens with or without shade from a galvanized steel-roof structure. Performance data (e.g., dry matter intake, body weight gain, feed efficiency and hot carcass weight) and heat stress indicators (e.g., subcutaneous temperature, body-surface temperature, respiratory rate and water intake) were assessed along the study period. The economic outcomes derived from shade implementation were determined using the net present value. Meteorological variables were also monitored every 1 min, and grouped in a thermal comfort index for feedlot cattle, the InComfort Index (InCI). The shade structure efficiently reduced radiant heat load on cattle in pens with shade. According to the classification of the InCI, during very hot days (InCI > 0.6; around noon with mean solar radiation above 800 W m-2 and mean air temperature above 33°C), greater proportion (80%) of animals in shaded pens were using shade. Under such circumstances, cattle in shade had water intake reduced by 3.4 L per animal, body temperature was lower by 5°C, subcutaneous temperature was lower by 1°C and respiration rate was lower by 10 breaths min-1 compared to animals in pens without shade (P = 0.0001). Although dry matter intake was similar (P = 0.6805), cattle in pens with shade had higher average daily gain reflected in a heavier hot carcass weight (8 kg animal-1; P = 0.0002). Considering an initial investment of $90 per animal to build a structure that lasts 15 years, the expected payback time is four finishing cycles (~110 days per cycle). In conclusion, this study confirms that the proposed novel shade design is economically profitable, improves performance, and enhances animal welfare.

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Research on biodiversity management in production systems involves various aspects, including selecting optimal population arrangements for cultivated plants. The utilization of unconventional vegetables, such as taioba (Xanthosoma sagittifolium (L.) Schott), in the diversification of production systems offers a promising alternative to enhance food security and income generation for producers. However, limited information exists in the literature regarding its management and production. Thus, the present study aimed to assess different planting densities of taioba cultivated in intercropping under banana orchards by evaluating its development and yield. The experiment was conducted at the Federal University of Espírito Santo (UFES), located in Alegre, ES, Brazil. The experimental design employed randomized blocks with six replications, following a split-plot arrangement. The plots consisted of single and double rows of planting systems, while the subplots were comprised of between-plant spacings of 30, 40, and 50 cm. Various parameters were evaluated, namely, leaf area, number of leaves, leaf fresh and dry matter, chlorophyll indices, flavonoids, and nitrogen balance. Additionally, gross income was determined by estimating the production capacity of leaves and converting it into the production capacity of commercial leaf bundles, considering a 1.0 ha taioba cultivation area based on the intercropping arrangements with banana trees. The highest fresh and dry matter yields of taioba were achieved with the largest spacing between plants (50 cm) in both single and double rows. The number of leaves produced by the plants remained unaffected by the studied arrangements. Consequently, the highest gross yield was obtained with the highest plant density, achieved through a planting spacing of 30 cm between plants in double rows. These findings underscore the viability of diversifying production within banana orchards by incorporating taioba planting in alternating rows, providing a genuine opportunity for additional income for farmers.(AU)

As pesquisas associadas ao tema de manejo da biodiversidade em sistemas de produção englobam diversos aspectos, dentre eles a escolha dos melhores arranjos populacionais das plantas cultivadas. A utilização de hortaliças não convencionais, como a taioba Xanthosoma sagittifolium (L.) Schott, na diversificação dos sistemas produtivos é uma ótima alternativa do ponto de vista de segurança alimentar do produtor e também para a geração de renda. Contudo, na literatura ainda são escassas as informações sobre seu manejo e produção. Nesse sentido, objetivou-se avaliar diferentes densidades de plantio de taioba cultivada em consórcio, sob pomar de bananeiras, verificando seu desenvolvimento e produção. O experimento foi realizado na área experimental da Universidades Federal do Espírito Santo (UFES), localizado no município de Alegre ES. O delineamento foi em blocos casualizados, com seis repetições, no esquema de parcelas subdivididas. As parcelas foram compostas pelos sistemas de plantio em linha simples e duplas. As subparcelas foram compostas pelos espaçamentos entre plantas de 30, 40 e 50 cm. Foram avaliadas a área foliar, número de folhas, matéria fresca e matéria seca de folhas, índices de clorofila, flavonoides e balanço de nitrogênio. Adicionalmente estimou-se a Renda Bruta, através da estimativa da capacidade de produção de folhas, transformada em capacidade de produção de maços de folhas comerciais, que seriam produzidos em 1,0 hectare de taioba, a partir dos arranjos adotados no consórcio com bananeiras. As maiores produções de matérias fresca e seca da taioba foram observadas quando se adotou o maior espaçamento entre plantas (50 cm), tanto em linha simples quanto em linhas duplas. Os arranjos estudados não influenciaram no número de folhas emitidas pelas plantas, por isso, o maior rendimento bruto foi obtido com a maior densidade de plantas, alcançada com o plantio no espaçamento de 30 cm entre plantas, em linhas duplas. Sendo assim, os resultados demonstram que a diversificação da produção do pomar de bananeira, com plantio de taioba em entrelinhas alternadas, representou uma real alternativa de renda extra ao agricultor.(AU)

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