Search Results (583)

Orchids exhibit remarkable diversity in terms of form, color, and fragrance, and are highly valued for their ornamental potential. In the Brazilian Cerrado, several native epiphytic species, including Cattleya cernua (Lindl.), are increasingly threatened by habitat loss and uncontrolled wild harvesting, leading to significant genetic erosion. In this context, conservation strategies and the development of optimized in vitro culture protocols are essential for preserving these species. This study optimized in vitro growth and established an acclimatization protocol for C. cernua by evaluating the effects of salt and sucrose concentrations, plant flour supplementation, and substrate types and fertilizer levels on acclimatization performance. Results indicated that the MS medium at 25% supplemented with 10 g L⁻¹ sucrose promoted the greatest shoot growth, number of leaves, and pseudobulb formation. The addition of cashew nut flour at 10 g L⁻¹ significantly enhanced both shoot and root development, increasing leaf and root numbers compared to other treatments. Data showed that coconut fiber, even without fertilization, supported high survival rates and robust plant growth. Collectively, these findings demonstrate that the in vitro growth of Cattleya cernua is most effectively achieved using MS medium at 25% strength supplemented with 10 g L⁻¹ sucrose and 10 g L⁻¹ cashew flour, followed by acclimatization in coconut fiber without additional fertilization. This protocol represents an efficient, sustainable strategy for propagating and conserving this native Cerrado orchid species. Full article

The palm swamp landscapes, particularly the Vereda wetlands and their associated swamp gallery forests (VED.SGF), comprise essential yet threatened ecosystems within the Brazilian Cerrado. In addition to supporting significant portions of biodiversity, they provide critical ecosystem services such as storing and filtering excess rainwater and serving as major carbon reservoirs in organic soils. These wetlands are directly linked to the drainage systems of the headwaters of the main Cerrado river basins, which together account for about two-thirds of Brazil’s hydrographic basins. Mapping and managing VED.SGF ecosystems through remote sensing present major challenges addressed in this first study. Their narrow, dendritic, and complex tabular spatial pattern, often elongated along watersheds on scales of hundreds of kilometers, suffering distortions due to human impact, and the limited amount of annotated data make segmentation particularly challenging. Existing deep learning (DL) methods, typically pre-trained on natural images, struggle to capture the spectral and spatial intricacies of these ecosystems. This study introduces a trained-from-scratch U-Net model supported by field-based experimental procedures to ensure high-quality wetland annotations. The resulting dataset covers approximately 7300 km² in western Bahia and provides domain-specific weights tailored to remote sensing applications. Using high-resolution (4.6 m) RGB mosaics, the model was trained, validated, and tested to establish a reproducible and scalable pipeline. The proposed method achieved robust results in an independent test area of 8040 km², with a mean IoU of 0.728, F1-score of 0.843, and Cohen’s Kappa of 0.837. These results demonstrate consistent performance and strong generalization to new areas, establishing a scientifically reliable baseline that situates the model competitively within the current state of the art. By releasing both the model weights and annotated dataset, this study provides valuable resources to advance future research on mapping and monitoring these unique and strategic wetland ecosystems. Full article

Recent genomic phylogenies have generated new robust classifications of actinopterygian fishes, making possible greater nomenclatural stability, but genus-level classifications of groups like the diverse catfish subfamily Trichomycterinae are still unclear, containing ill-defined paraphyletic taxa. The focus of the present study is the Trichomycterus Lineage (TL), a clade with great morphological diversity, containing about 170 species widely distributed in South America, occurring in the most important biodiversity hotspots of the world, such as the Atlantic Forest, Cerrado, and the Tropical Andes. Most species are small, but at least one reaches about 400 mm of total length, being used as food and depicted in pre-Hispanic Andean ceramics. Based on a comparative morphological analysis, mainly using osteological characters, supported by concordant genomic phylogenies, a new classification at the genus level is here provided. Many morphological features delimiting TL genera seem to be related to ecological adaptations. Nine genera are here recognised of which five are new. Recognition of the new genera will allow easier descriptions of new species and consequently better biodiversity estimates. Full article

Soil water retention and availability are influenced by intrinsic soil properties, management practices, and climate regimes. This study aimed to evaluate water retention and availability in an Ultisol under different integrated production systems in the Brazilian Cerrado. The systems analyzed included Crop–Livestock Integration (CLI), Livestock–Forest Integration (LFI), Crop–Forest Integration (CFI), no-tillage (NT) and native Cerrado vegetation (NV). Disturbed samples were collected for physical and chemical characterization, while undisturbed samples were used to determine water retention curves at depths of 0.00–0.10, 0.10–0.20, and 0.20–0.40 m. From these curves, water availability, pore-size distribution, differential log-pore-radius curves, most frequent pore radius, and relative hydraulic conductivity were estimated using the Mualem–van Genuchten model. Confidence intervals were used to evaluate differences between retention curves. The CLI system showed lower water content at saturation (14–30%) and field capacity (10–20%) compared to CFI, LFI, and NT. The NT system exhibited higher water availability across all layers (28, 48, and 46%, respectively) than CLI. Alterations in pore structure, likely due to the short integration period and monoculture history in CLI, resulted in lower water retention. Conversely, CFI, LFI, and NT showed higher retention and availability, attributed to higher organic matter content and more stable structural pores. Integrated production and no-tillage systems, especially when adopted long-term, enhance soil water retention and availability in the Brazilian Cerrado. Full article

Bowdichia virgilioides Kunth is a tree largely present in South America, notably in the Cerrado savannah. The species is known for the quality of its dense and resistant wood, used in construction and furnishing. B. virgilioides is also a medicinal plant used, from leaves to roots, for the treatment of various human pathologies (pharyngitis, bronchitis, healing wounds, diabetes, and arthritis). The present review provides an analysis of the scientific literature pertaining to B. virgilioides, with a focus on pharmacological activities. Aqueous and organic extracts have been used to treat inflammatory pathologies and to combat infectious diseases caused by microorganisms and parasites. All phytochemicals at the origin of the bioactivities of extracts have been identified, including 37 terpenoids, 8 alkaloids, 21 flavonoids and 13 other products. All natural products are discussed, with a focus on a dozen compounds with well-documented pharmacological properties and/or a known mechanism of action. Key products include ormosanine (alkaloid), vouacapane (diterpenoid), lupeol (terpenoid), isoquercetin (flavonoid), isocordoin (chalcone), and little-known specific products (bowdichine and bowdenol). The botanical and phytochemical analysis shed light on this valuable Fabaceae species with the objective to promote its preservation and cultivation, as well as further pharmacological investigations aimed at rationalizing its long-established ethnobotanical use. Full article

The selection of superior maize genotypes is complex due to the quantitative and intercorrelated nature of agronomic traits and their strong environmental influence, which limits the efficiency of direct selection and requires multivariate approaches. This study aimed to compare the efficiency of seven selection indices in identifying superior maize hybrids, quantify the genetic gains provided by each method, and evaluate the agreement among indices in genotype classification under Brazilian Cerrado conditions. Seventy-three maize genotypes were evaluated across multiple environments, considering grain yield and lodging resistance as primary traits and plant health, earliness, plant height, and ear height as secondary traits. The evaluated indices included direct and indirect selection, the Smith–Hazel classical index, the desired genetic gains of Pesek and Baker, the weight- and parameter-free index of Elston, the multiplicative index, the rank sum index of Mulamba and Mock, and the Genotype–Ideotype index. The results revealed differences in efficiency among methods for simultaneous trait selection. The Elston, Mulamba and Mock index and the Genotype–Ideotype index provided a better balance between productivity and other agronomic traits, resulting in more balanced genetic gains. In contrast, the Pesek and Baker and multiplicative indices were less efficient for joint selection, while direct selection and the Smith–Hazel index were more effective when applied to isolated traits. Overall, the combined use of indices improved selection reliability and enabled the identification of superior and more stable genotypes for the Cerrado. Full article

In the Cerrado, phosphorus (P) availability is limited inter alia by the chemical characteristics of the soil. This study aimed to evaluate the effects of different sources and rates of phosphate fertilizers on P dynamics, soybean productivity, and plant nutrition in Glycine max cultivated in a Yellow Oxisol of the Maranhão Cerrado. Two experiments were conducted in a randomized complete block design during the 2021/2022 growing season. The first experiment followed a 5 × 3 factorial design, with five P sources (one control and four corrective sources) and three soil sampling depths. The second experiment used the corrective fertilization history of the areas from the first study as the first factor and three P₂O₅ rates applied at sowing as the second factor, with three replications. In the soil, Fe-bound P (P-Fe), Ca-bound P (P-Ca), Al-bound P (P-Al), and available P were evaluated; in the plant, grain yield, thousand-grain weight, total dry matter, and P concentration in leaves, grains, and the whole plant were determined. An interaction between P sources and soil depths was observed for P-Fe and P-Ca (0–0.10 > 0.10–0.20 > 0.20–0.40 m), indicating low vertical mobility of P in the soil profile. In addition, increasing P₂O₅ rates raised P contents in the soil and plant tissues across all treatments. For the Itafós source, soil P increased from 2.66 to 4.22 mg kg⁻¹ at 0.0 and 120.0 kg ha⁻¹ of P₂O₅, respectively, which resulted in a marked increase in soybean grain yield, rising from 1484.93 kg ha⁻¹ at 0.0 kg ha⁻¹ to 3418.60 kg ha⁻¹ at 120.0 kg ha⁻¹ of P₂O₅, highlighting the importance of adequate phosphate fertilization for agricultural systems in Cerrado soils. P-Al showed a positive correlation with soil available P, whereas P-Fe was correlated with the treatments TSP10, TSP0, and Itafós20. Full article

This study evaluated the effects of ammonium sulfate [(NH₄)₂SO₄] addition and land-use history on greenhouse gas emissions (CH₄, CO₂, N₂O) and inorganic nitrogen dynamics (NH₄⁺ and NO₃⁻) in Brazilian Cerrado soils. The objective was to determine how fertilization interacts with native and agricultural soils to regulate key biogeochemical processes. Soil samples from native and agricultural areas were collected in four regions (Araras, Sorocaba, Itirapina, and Brasília), representing contrasting pedoclimatic conditions and soil textures under different cropping systems. Samples were incubated under controlled conditions, with greenhouse gas fluxes analyzed by gas chromatography and inorganic nitrogen concentrations determined by colorimetric methods. Nitrogen fertilization inhibited CH₄ consumption in native and agricultural soils and reversed fluxes to emissions in sandy soils. CO₂ emissions increased in native soils but decreased in agricultural soils, suggesting effects of soil fertility and carbon stocks. N₂O emissions increased mainly in native soils, reflecting intensified nitrification and denitrification, whereas agricultural soils responded heterogeneously. Nitrogen addition altered NH₄⁺ and NO₃⁻ consumption, indicating enhanced oxidation and microbial assimilation. These results demonstrate that land-use history influences soil biogeochemical responses to nitrogen, underscoring the importance of site-specific fertilization in mitigating emissions and promoting sustainability in the Cerrado. Full article

Spodoptera eridania (Cramer, 1792) is increasingly reported from potato (Solanum tuberosum L., Solanaceae) in the Brazilian Cerrado, where infestations can cause substantial yield losses. Insecticides may alter the behavioral ecology of agricultural pests. The adaptability of S. eridania mediated by insecticides, especially regarding oviposition behavior, remains poorly understood. This study aimed to evaluate the spatial distribution and oviposition traits of S. eridania on potato plants under chlorfenapyr spraying. Egg masses were collected weekly, day after planting (DAP), totaling 322 collections up to the 91st DAP. Evaluations included the vertical plant strata (upper, middle and lower thirds), leaf surface (adaxial vs. abaxial), and density of scales covering egg masses (high, low, or absent). Results showed that nearly 90% of egg masses were deposited in the upper and middle thirds of the plants. Insecticide spraying modulated oviposition behavior because females preferred the middle third in treated plants, whereas oviposition predominated in the upper third of untreated plants. Moreover, under chlorfenapyr, 93.0 ± 1.2% of egg masses were placed on the abaxial surface. These findings highlight the role of insecticide-mediated behavioral shifts in shaping host-pest interactions and provide relevant insights for integrated pest management of S. eridania in potato field systems. Full article

The conversion of native forests into agricultural areas without conservation practices can expose tons of soil organic carbon (SOC) to the atmosphere. This study aimed to evaluate the effect of land use and cover (LULC) on C in regions of the Caiabi (SBC) and Renato (SBR) River sub-basins, located in the Brazilian Cerrado–Amazon transition. Data on physical attributes and SOC were obtained by region (upper, middle, and lower), LULC (cropland, pasture, and native forest), and depth (0–10, 10–20, and 20–40 cm), with five replicates for each variable. The highest SOC values were found in areas with higher clay contents or in areas of native forest or crop residues. In the SBC, there was a negative correlation of SOC with sand and particle density (PD) and a positive correlation with silt. In the SBR, there was a positive correlation between SOC and microporosity and total porosity, and a negative correlation with sand, soil bulk density, and PD. The highest SOC values were found in the SBC upper region, in native forest (107 Mg ha⁻¹), cropland (69 Mg ha⁻¹), and pasture (49 Mg ha⁻¹). In the SBR upper region, the values were highest in pasture and cropland (93 and 58 Mg ha⁻¹), and in the lower region, the values were highest in native forest (48 Mg ha⁻¹). SOC varied in relation to the SBC and SBR regions, the LULC, depth, and physical attributes, especially soil texture. Full article

The Amazon Deforestation Arc remains a critical region for environmental governance, where land-use strategies must consider distinct legal and institutional frameworks across the Amazon and Cerrado biomes. This study applies the Potential Productivity Model (M3P), a theoretical radiation-based framework, to estimate the upper physiological limits of sugarcane (Saccharum officinarum L.) productivity on degraded pastures within the Arc of Deforestation. The model integrates satellite-derived solar radiation with climatic variables to quantify potential productivity under optimal biophysical conditions, providing an objective benchmark for planning-oriented bioenergy assessments. Estimated potential yields range from 153 to 178 t·ha⁻¹·yr⁻¹, consistent with global reference values reported for sugarcane in high-radiation environments and relevant for informing public policies such as Brazil’s Agroecological Zoning of Sugarcane. The results demonstrate that agroclimatic potential alone is insufficient to guide land-use decisions. While degraded pastures associated with the Cerrado biome may accommodate sugarcane cultivation as part of productive land recovery strategies, areas belonging to the Amazon biome require priority actions focused on ecological restoration through agroforestry and integrated crop–livestock–forest systems. Overall, the M3P model offers a scalable and scientifically grounded decision-support framework for strategic planning in environmentally sensitive tropical regions. Full article

Macauba (Acrocomia aculeata) is a promising source of vegetable oils with distinct applications for its pulp and seed fractions. This study presents the first comprehensive quantitative analysis of eleven commercial macauba oils available in the Brazilian market, using validated methods of GC-FID and LC-HRMS. The analysis revealed significant variability among samples. Control pulp oils (PCCs) were characterized by the predominance of oleic acid (C18:1) and palmitic acid (C16:0) methyl esters, and TG 54:3 was the major lipid species, reaching up to 12.11 g 100 g oil⁻¹. For control seed oils (SCCs), the profile was dominated by lauric acid (C12:0) and oleic acid methyl ester; TG 36:0 was the most abundant lipid, which reached concentrations of 49.20 g 100 g oil⁻¹. Among commercial samples, PC3 followed the expected pulp oil profile, whereas PC4 showed deviations. Others commercial samples (PC2, PC5, SC3, SC4, SC5) deviated significantly from expected profiles, showing high levels of linoleic acid (C18:2), and predominance of TG 54:6, with concentrations reaching 61.74 g 100 g oil⁻¹. The integrated GC-FID and LC-HRMS approach provides robust, sensitive, and discriminative analysis of FAMEs and lipid composition of macauba oil samples. These methodologies are essential for quality control in the food and bioproduct sectors, ensuring the chemical integrity of macauba commercial oils. Full article

Understanding the spatial structure of large mammals is critical for conservation planning, especially under increasing habitat fragmentation. This study applies an integrated spatial analysis combining the DBSCAN density-based clustering algorithm and the α-hull method to delineate non-convex geographic ranges of the maned wolf (Chrysocyon brachyurus) across South America. Using 454 occurrence records filtered for ecological reliability, we identified 11 geographically isolated α-populations distributed across five countries and multiple biomes, including the Cerrado, Chaco, and Atlantic Forest. The sensitivity analysis of the α parameter demonstrated that values below 2 failed to generate viable polygons, while α = 2 provided the best balance between geometric detail and ecological plausibility. Our results reveal a highly fragmented distribution, with α-populations varying in area from 43,077 km² to 566,154.7 km² and separated by distances up to 994.755 km. Smaller and peripheral α-populations are likely more vulnerable to stochastic processes, genetic drift, and inbreeding, while larger clusters remain functionally isolated due to anthropogenic barriers. We propose the concept of ‘α-population’ as an operational unit to describe geographically and functionally isolated groups identified through combined spatial clustering and non-convex hull analysis. This approach offers a reproducible and biologically meaningful framework for refining range estimates, identifying conservation units, and guiding targeted management actions. Overall, integrating α-hulls with density-based clustering improves our understanding of the species’ fragmented spatial structure and supports evidence-based conservation strategies aimed at maintaining habitat connectivity and long-term viability of C. brachyurus populations. Full article

This study aimed to develop a methodology to evaluate, through RGB image processing, the wheat cultivar TRIO Calibre under three irrigation levels (100, 50, and 25%), with or without the application of Bacillus aryabhattai, in Brazilian Cerrado soil. The experimental scheme was a $3\times 2$ factorial design with five replicates. Images were collected, numbered, and organized into files, which were transformed to grayscale. During processing, the grayscale level co-occurrence matrix (GLCM) technique was applied and implemented in four main directions (0°, 45°, 90°, and 135°), and 13 statistical descriptors were extracted. At physiological maturity, the plants were harvested, and the following yield components were evaluated: plant height (PH), number of spikes per plant (NS), number of grains per spikes (NGS), average grain weight (AGW), and total prodution of grains (TPG). Irrigation influenced all the variables, with higher TPG and NS at 100% and 50% water and higher AGW at 25% water. The results indicated that the “contrast” descriptor in the 90° and 135° GLCM directions was the most efficient in differentiating treatments, which presented better performance in the 90° direction and was significantly correlated with the NS ($r=-0.48$, $p<0.05$) and TPG ($r=-0.46$, $p<0.05$). The analyses demonstrated that the methodology has the potential to be adapted for the analysis of under controlled conditions, contributing to more sustainable agricultural practices. Full article

Murundus fields (wetland earth-mounds) represent a relatively understudied physiognomy in the Cerrado biome. This study aimed to evaluate the composition, life history, phytosociology, endemism, and conservation status of woody plant species in murundus fields in a forestry-dominated landscape in the Brazilian savanna. We established 40 plots, each measuring 50 × 20 m, where all live shrub-arboreal plants with a trunk diameter at the base of ≥1 cm and a height > 0.5 m were identified. Using these data, we calculated the absolute and relative values of density, dominance, and frequency, as well as the importance value index. In addition, we estimated Shannon’s and Simpson’s diversity indices and Pielou’s equability index. Our findings included 155 species, 69 genera, and 38 families in the study area. The invasive exotic species Pinus caribaea Morelet showed the highest importance value, followed by Jacaranda caroba (Vell.) DC., Miconia albicans (Sw.) Steud., Erythroxylum suberosum A.St.-Hil., and Miconia fallax DC. The pronounced presence of P. caribaea is a matter of concern and highlights the need for control measures, given its potential to hinder the regeneration of native species. We identified species occurring in various Cerrado phytophysiognomies, suggesting that murundus fields function as transitional habitats. This study underscores the importance of conserving species within the inadequately studied Cerrado physiognomy. Full article