https://repositorio.ufu.br/handle/123456789/18942 2026-09-13T11:43:34Z 2026-09-13T11:43:34Z https://repositorio.ufu.br/handle/123456789/50223 2026-09-12T06:28:01Z 2026-04-09T00:00:00Z

Title: Residual do clomazona no solo e influência nas culturas do alho e cebola Abstract: The presence of herbicide residues in the soil can compromise the establishment of crops such as garlic (Allium sativum L.) and onion (Allium cepa L.) in succession systems. Clomazone, widely used in soybean as a pre-emergence herbicide, plays an important role in reducing the selection pressure of resistant weeds; however, its residual activity may negatively affect sensitive crops grown in succession. Thus, this study aimed to evaluate the residual effect of clomazone on garlic and onion, in order to determine safe intervals between herbicide application and crop planting. The experiment was conducted under field conditions in a sandy clay loam soil. The experimental design was a randomized complete block design with three blocks and seven treatments, corresponding to different intervals between clomazone application (1.5 L ha⁻¹) and crop planting: control treatment (without herbicide), 0, 30, 60, 90, 120, and 150 days after application (DAA), where DAA represents planting on the same day as herbicide application. Phytotoxicity, plant stand, plant height, and yield were evaluated. Data were subjected to analysis of variance assumptions at a 5% significance level. Subsequently, analysis of variance was performed, with stand, height, and yield compared to the control using Dunnett’s test (5%), while phytotoxicity was modeled using exponential regression with a zero asymptote. For garlic, yield did not differ significantly from the control when planting was performed from 30 days after application onwards. Exponential regression indicated a gradual dissipation of the residual effect, with the absence of visual injury symptoms estimated at approximately 75 days after application. For onion, a more sensitive crop, significant yield reductions were observed when planting occurred up to 60 DAA. Exponential regression indicated that residual phytotoxicity may persist for a longer period, with curve stabilization estimated at approximately 120 days after application. These results demonstrate greater tolerance of garlic and higher sensitivity of onion to clomazone. Under the conditions of this study, the results indicate minimum safe intervals of approximately 75 days for garlic and 120 days for onion, which may vary depending on soil texture and edaphoclimatic conditions.

2026-04-09T00:00:00Z https://repositorio.ufu.br/handle/123456789/50218 2026-09-12T06:28:11Z 2026-05-21T00:00:00Z

Title: Atributos físicos, químicos e estoque de carbono em solos de uma topossequencia sob regeneração natural no Triângulo Mineiro Abstract: This study aimed to evaluate the physical and chemical attributes of soil, as well as to quantify the total organic carbon content and carbon stock in different soil classes along a toposequence in the Triângulo Mineiro region, in the municipality of Uberaba, Minas Gerais, Brazil, in order to understand the spatial and vertical variability of these attributes and their interrelationships in soil quality. The studied toposequence was approximately 1,000 m long. The experimental design was a randomized complete block design with a split-plot arrangement, consisting of five soil classes: Oxisol (LV), Red-Yellow Oxisol (LVA), Cambisol (CA), Haplic Gleysol (GH), and Melanic Gleysol (GM), and two sampling depths (0.00–0.10 and 0.10–0.20 m), with five replicates. Physical soil attributes were evaluated, including bulk density, macro- and microporosity, total porosity, and aggregate stability and distribution, as well as chemical attributes related to soil fertility, such as pH and macro- and micronutrient contents. Total organic carbon (TOC) content and soil organic carbon stock (SOC stock) were also determined. The data were subjected to statistical analysis to identify differences among soil classes, sampling depths, and their interactions. The results showed that the hydromorphic soils, particularly the Melanic Gleysol (GM), presented higher total organic carbon contents and soil organic carbon stocks, which were associated with greater water saturation and lower rates of organic matter decomposition. In contrast, the Oxisols (LV and LVA) and the Cambisol (CA), located in higher and well-drained landscape positions, exhibited lower soil organic carbon stocks and better structural conditions. It was concluded that topography plays a decisive role in the distribution of the physical, chemical, and carbon-related attributes along the toposequence, highlighting the importance of this approach for sustainable soil management and land-use planning.

2026-05-21T00:00:00Z https://repositorio.ufu.br/handle/123456789/50009 2026-09-03T06:26:11Z 2024-11-25T00:00:00Z

Title: Características agronômicas envolvidas na adaptação de híbridos de milho em condições de primeira e segunda safra Abstract: The search for more productive corn hybrids, resistant to the main diseases that affect the crop and adapted to different sowing times, has been the target of breeding programs. The hypothesis of the research is that the sowing times affect the characteristics and productivity of corn by interacting with the environment. Thus, the aim of the research is to identify agronomic characteristics associated with the wide adaptation of corn hybrids in first and second crop conditions, in order to contribute to hybrid selection strategies by corn breeding programs. The experiments were carried out under field conditions in the 2022/23 harvest at the Corteva research station in the municipality of Indianópolis-MG. A randomized block design was used in a factorial scheme with five sowing times and sixteen hybrids, with three replications. height, ear insertion height, flowering, number of days between planting and physiological maturation, leaf length, leaf width, number of green leaves, leaf area index, severity score for Bipolaris maydis, percentage of plants with stunting, shoot dry mass (stem + leaf + ear) of corn, weight of a thousand seeds and grain yield were valued data were submitted to individual and joint analysis of variance, and when differences were observed between the treatments by the F test, the means were grouped by the Scott-Knott test. We conclude that the shoot dry mass and weight of one thousand seeds can be used to identify hybrids with wide adaptation in first and second crop condition.

2024-11-25T00:00:00Z https://repositorio.ufu.br/handle/123456789/49969 2026-08-29T06:25:07Z 2026-04-24T00:00:00Z

Title: Alterações dos atributos físicos e estoque de carbono do solo em diferentes sistemas de manejo no Cerrado Abstract: The conversion of native Cerrado areas into agricultural systems has promoted changes in soil physical attributes and organic carbon dynamics, potentially affecting soil structure maintenance, water availability, and carbon storage capacity in cultivated environments. This study evaluated the effects of different sugarcane management systems on soil physical attributes and organic carbon stocks in Red Latosols in the Triângulo Mineiro region, Minas Gerais, Brazil. Six soil use and management systems were evaluated: Conv. 2 (conventional cultivation with two years of implementation), Conv. 3 (conventional cultivation with three years of implementation), Min. Till. 2 (minimum tillage with two years of implementation), Min. Till. 3 (minimum tillage with three years of implementation), Pasture, and Native Forest as an environmental reference. Soil samples were collected at depths of 0–10, 10–20, and 20 40 cm and analyzed for soil bulk density, macroporosity, microporosity, total porosity, mean weight diameter, geometric mean diameter, aggregate stability index, total organic carbon, and carbon stocks. The experiment was conducted in a completely randomized design in a factorial arrangement, considering six management systems, three soil depths, and five replications. Data were subjected to analysis of variance, and means were compared using Tukey’s test at a 5% significance level. The results demonstrated that management was the main factor responsible for changes in the evaluated attributes, whereas soil depth and the interaction between management and depth had a lower influence on most variables. The Min. Till. 3 system showed more favorable soil physical conditions, characterized by lower soil bulk density, higher macroporosity (24.17%), and higher total porosity (47.93%), presenting a similar behavior to Native Forest. The attributes related to aggregate stability showed greater structural preservation in Pasture and Native Forest systems, which presented higher values of geometric mean diameter, mean weight diameter, and aggregate stability index, highlighting the importance of permanent soil cover and continuous organic residue input. Management systems also influenced total organic carbon contents, with higher values observed in Min. Till. 2, Conv. 2, and Min. Till. 3 systems. Carbon stocks were affected by the evaluated management systems, with Min. Till. 3 presenting the highest carbon stock (43.40 Mg ha⁻¹), followed by Pasture and Native Forest. It is concluded that conservation management systems, especially minimum tillage after three years of implementation, have the potential to improve soil physical quality and increase carbon stocks in sugarcane cultivated areas in the Cerrado, contributing to agricultural sustainability strategies and natural resource conservation.

2026-04-24T00:00:00Z