https://repositorio.ufu.br/handle/123456789/5161 2026-09-22T13:09:06Z 2026-09-22T13:09:06Z https://repositorio.ufu.br/handle/123456789/50303 2026-09-18T06:23:23Z 2026-08-07T00:00:00Z

Title: Uma perspectiva histórica e espacial da ocorrência e distribuição de populações de Calophyllum brasiliense Cambess. e Platymiscium ulei Harms no Médio Solimões, Amazonas Abstract: Historical logging in the Middle Solimões region drastically reduced populations of Calophyllum brasiliense (Jacareúba) and Platymiscium ulei (Macacaúba), creating an urgent need to understand their current spatial arrangements to support management and conservation efforts. This study investigated the occurrence and structure of three Jacareúba populations (JAC1, JAC2, JAC3) and two Macacaúba populations (MAC1, MAC2) in the Mamirauá Sustainable Development Reserve, correlating them with soil physicochemical attributes collected in the field between 2023 and 2025 (with analytical determinations completed in 2026). The methodology integrated geostatistical tools (variography, ordinary kriging, cross-validation) and multivariate analysis (Exploratory Factor Analysis) applied to 313 georeferenced tree specimens and 259 soil samples. Results revealed contrasting post-disturbance trajectories. C. brasiliense maintained, across its clusters, an aggregated spatial pattern with moderate spatial dependence and practical ranges between 274 m and 288 m, demonstrating resilience and autonomous recovery capacity. In contrast, P. ulei exhibited an independent pattern with Pure Nugget Effect in both remaining populations, characterizing severe demographic collapse associated with a potential Allee effect. In MAC1, the species was restricted to an equally random bipolar fertility/acidity gradient (pH, V, H+Al), whereas in MAC2 the abiotic matrix proved chaotic, precluding Factor Analysis (KMO = 0.17). It is concluded that the same historical pressure produced distinct dynamic responses according to the intrinsic vulnerability of each taxon. Passive protection is sufficient for Jacareúba regeneration, whereas Macacaúba requires active enrichment interventions and differentiated silvicultural management.

2026-08-07T00:00:00Z https://repositorio.ufu.br/handle/123456789/50282 2026-09-16T06:21:42Z 2026-04-30T00:00:00Z

Title: Caracterização in silico de STRs em genomas de Aspergillus niger visando ao desenvolvimento de marcadores moleculares para cepas de bioinsumos agrícolas Abstract: Soil microbiota, particularly fungi, play a central role in plant growth promotion and nutrient cycling. Among them, Aspergillus niger stands out due to its biotechnological potential, contributing to phosphate solubilization and enhancing plant development. However, the application of such microorganisms requires robust strategies to enable precise and reliable tracking of the fate and behavior of introduced strains under environmental conditions. In this context, this study advances the genomic characterization of A. niger by focusing on microsatellites (short tandem repeats, STRs) for the identification of genetic markers with high discriminatory power among strains, through an integrated in silico workflow of detection, variability assessment and validation. In addition to expanding the characterization of these markers, the proposed strategy provides an efficient, reproducible, scalable, and cost-effective computational framework that reduces reliance on experimental procedures during the early stages of molecular marker development.

2026-04-30T00:00:00Z https://repositorio.ufu.br/handle/123456789/50276 2026-09-16T06:21:39Z 2026-02-26T00:00:00Z

Title: Avaliação do crescimento inicial da cultura do cafeeiro em sistemas agroflorestais no cerrado mineiro, Uberlândia, Minas Gerais Abstract: Agricultural expansion in the Cerrado requires production models that reconcile yield with climate resilience. This dissertation evaluated the initial growth of coffee (Coffea arabica L. cultivar Mundo Novo) in biodiverse Agroforestry Systems (AFSs) and in a diversified vegetable garden area, aiming to understand the influence of these systems on the initial vegetative development of the crop in the Uberlândia-MG region. Biometric parameters (height, stem diameter, and number of leaf pairs) were analyzed, along with their correlation with shading dynamics, associated biodiversity, and the physical and chemical attributes of the soil in different AFS arrangements. The research was conducted at two sites with distinct forest compositions and soil types. The experiment consisted of seven treatments, each corresponding to a single plot. Each plot contained three planting lines with 30 coffee seedlings per line, totaling 90 individuals per treatment and 630 plants overall (7 treatments × 90 seedlings). Over the crop cycle, nine biometric evaluations were carried out, recording data on plant height, stem diameter, number of leaf pairs, and count of established plants for all individuals. The methodology included nine biometric evaluations over one year, quantitative measurement of light intensity at different points within the systems, and a detailed floristic survey to characterize biodiversity. Biometric data were analyzed using the non-parametric Friedman test. The results showed that the oldest AFSs (established in 2015 and 2019) provided the best conditions for initial establishment, with significantly superior performance in all growth variables compared to the full-sun area. Light intensity analysis revealed a shading gradient directly related to the age and structural complexity of the systems, while the floristic survey evidenced greater species diversity in the more consolidated AFSs. It is concluded that the structure and maturity of the AFSs were decisive for creating a favorable microclimate and for the successful initial establishment of coffee in the Cerrado, suggesting that this model offers an effective strategy to increase crop resilience. The results indicate that different agroforestry designs influence the initial growth dynamics of coffee. Based on these results, future investigations focusing on the specific characteristics and challenges of coffee farming in the region are proposed.

2026-02-26T00:00:00Z https://repositorio.ufu.br/handle/123456789/50260 2026-09-15T06:23:18Z 2023-02-17T00:00:00Z

Title: Implicações da adição de fontes de fósforo sob indicadores microbianos e bioquímicos do solo Abstract: Phosphorus is a vital nutrient for terrestrial organism due to its importance in cellular metabolism. Highly weathered soils have low availability of P in the soil solution due to the adsorption of phosphate in the soil matrix, such as iron and aluminum oxides. The soil microbiota is preponderant in the availability of P in the soil solution due to the dynamics of immobilization and mineralization and rapid cycling. The objective of this work was to evaluate the impact of the addition of different P sources on soil microbial and biochemical indicators (Soil microbial respiration (SMR); Microbial Biomass Carbon (MBC); Soil Metabolic Quotient (qCO₂); FDA; acid phosphatase activity). The work was carried out on a sample of a Oxisoil, collected in Uberlândia, MG. The experiment was installed in a glass flask (600 mL) with 100 g of soil and 300 mg of P kg⁻¹ of soil was added. The treated with four replications were assembled to evaluate the source of P: 1- control, 2- potassium monophosphate (KHPO₄), 3- simple superphosphate, 4- phosphate rock dust, 5- phytic acid, 6- inositol. The results show that phytic acid had a significant increase compared to the other sources, with a lower SMR value being observed in the treatment with KHPO₄ of the phosphate sources. The addition of P, regardless of the source, tends to decrease MBC in the soil compared to the control treatment, leading to an increase in qCO₂ in the treatments with P addition. The addition of P sources significantly affects the FDA activity, with the highest values found in the treatment with the addition of KHPO₄. A lower FDA activity was not found in the phytic acid treatment. Treatments with P did not affect the phosphatase activity in the soil when compared to the control treatment. Concluded that the addition of phosphorus sources differentially alters soil metabolism, but this alteration may be specific to a soil bioindicator.

2023-02-17T00:00:00Z