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dissertação
Indução de resistência a Leucoptera coffeella em Coffea arabica com fungos endofíticos
(Universidade Federal de Lavras, 2026-07-27) Guerra, Thiago Sampaio; Cardoso, Patrícia Gomes; https://orcid.org/0000-0002-0797-2502; Souza, Bruno Henrique Sardinha de; https://orcid.org/0000-0002-2802-2688; Moino Junior, Alcides; https://orcid.org/0000-0002-8566-0694; Costa, Daniel de Carvalho Melo; https://orcid.org/0000-0003-4517-5069; Guimarães, Sarah da Silva Costa; https://orcid.org/0000-0002-6291-0718
The coffee leaf miner, Leucoptera coffeella, is one of the most important pests of Brazilian coffee production, causing significant losses by reducing the photosynthetically active leaf area of plants. The intensive use of insecticides for its control has encouraged the search for more sustainable management strategies, including the use of endophytic microorganisms capable of inducing plant resistance. In this context, the present study evaluated the potential of Muscodor spp. isolates to induce resistance in Coffea arabica against L. coffeella. Experiments were conducted under controlled conditions to evaluate oviposition preference, initial infestation establishment, and possible antibiosis effects on mine development and the insect life cycle. In the choice assay, treatments significantly affected the numbers of eggs and mines when compared with one another. Isolate CML 4010 showed the lowest numerical mean number of eggs, whereas CML 4009, CML 4010, CML 4015, and CML 4019 showed the lowest numerical mean numbers of mines; however, none of these isolates differed significantly from the control for the respective variables. Therefore, the results did not provide sufficient evidence to characterize antixenosis resistance. In the antibiosis assay, isolates CML 4009 and CML 4019 showed the smallest mined leaf areas, reducing mine development by 58% and 71%, respectively, at 14 days after fungal application. These same isolates reduced pupal formation and adult emergence by 87.5% compared with the control. The results indicate that Muscodor spp. isolates can affect the interaction between coffee plants and L. coffeella, with more consistent effects on insect development associated with antibiosis. Among the isolates evaluated, CML 4019 showed the most consistent performance across different stages of the L. coffeella life cycle, highlighting its potential for use in integrated pest management programs.
dissertação
Otimização espacial do microplanejamento da colheita florestal
(Universidade Federal de Lavras, 2026-06-18) Barbosa, Irene Maria Barcelos; Gomide, Lucas Rezende; https://orcid.org/0000-0002-4781-0428; Carvalho, Luis Marcelo Tavares de; https://orcid.org/0000-0003-3516-987X; França, Luciano Cavalcante de Jesus; https://orcid.org/0000-0002-8885-972X; Carvalho, Luis Marcelo Tavares de; https://orcid.org/0000-0003-3516-987X
The operational microplanning of forest harvesting, which encompasses the subdivision of forest stands into work strips and the strategic location of wood pile points, is frequently conducted empirically by forest companies, without the support of mathematical optimization models. This gap results in excessive machinery movement, higher operational costs, and avoidable environmental impacts. The incorporation of operational research techniques and grid-based spatial discretization into harvest planning allows this problem to be modeled as a capacitated location-allocation challenge, with the potential to significantly reduce extraction and machinery movement costs. In this context, the present study developed and evaluated a microplanning methodology based on the Capacitated p-Median Problem (CPMP), implemented through the Simulated Annealing (SA) metaheuristic and validated against Integer Linear Programming (PLI) in terms of solution quality and computational efficiency. The study was conducted in three forest stands located in the state of Mato Grosso do Sul, Brazil, with distinct levels of geometric uniformity, characterized by the Patton edge index, from which twelve experimental instances were constructed with different grid granularities. Results demonstrated that SA presented a significant computational advantage across all evaluated instances, with processing time reductions ranging from 50% to 90% compared to PLI. For smaller instances, SA achieved objective function values equivalent to or lower than those of PLI. In more complex instances, PLI tended to provide lower total cost solutions when convergence was reached; however, it failed to generate feasible solutions for three of the twelve instances, whereas SA produced solutions for all evaluated scenarios. It is concluded that SA represents a computationally efficient, scalable, and operationally robust alternative for forest harvest microplanning, being especially recommended for large-scale instances or situations where response time is a critical constraint. The results confirm the viability and competitiveness of metaheuristic approaches at this level of planning, contributing to the consolidation of scientific methodologies applied to the operational management of the Brazilian forest sector.
dissertação
Comparação de teor de carbono no solo no bioma Cerrado: recuperação de pastagens degradadas e integração pecuária floresta
(Universidade Federal de Lavras, 2026-05-26) Faria, Victor Azevedo; Roque, Cassiano Garcia; https://orcid.org/0000-0001-6872-0424; Terra, Marcela de Castro Nunes Santos; https://orcid.org/0000-0003-4646-2414; Assis, Thiago Rodrigo de Paula; https://orcid.org/0000-0002-5330-8856; Oliveira, Job Teixeira de; https://orcid.org/0000-0001-9046-0382; Teixeira, Elaine Cristina; https://orcid.org/0000-0001-5215-8238
The Brazilian Cerrado stands out for its grain production and cattle farming. Reaching the current level of crop intensification has required changes in land use, which have resulted in significant greenhouse gas (GHG) emissions in Brazil. In this context, technologies such as the Recovery of Degraded Pastures (RDP) and Integrated Crop-Livestock-Forestry (ICLF) systems are promising strategies for mitigating these emissions and improving productivity. This study aimed to estimate and compare soil carbon content among different production systems (recovered pastures, degraded pastures, integrated crop-livestock-forestry systems, and dense forest), as well as to assess factors affecting carbon accumulation. Soil samples were collected from approximately 2,880 hectares at depths of 0–0.20 m and 0.20–0.40 m, totaling 278 samples. Following the issuance of the soil analysis reports, carbon content was estimated based on the organic matter present in the samples. Subsequently, correlations between carbon content and soil texture and base saturation were evaluated. Significant and positive correlations were found between carbon content and both soil texture and base saturation, with soil texture being the more important factor. Thus, it was observed that more clayey soils tend to accumulate greater amounts of carbon, as do soils with better chemical conditions, that is, higher base saturation. Furthermore, within the soil depths evaluated in this study, the production systems did not have a substantial influence on soil carbon content, suggesting that soil management may have a greater effect in shallower layers, where most of the organic matter is stored.
dissertação
Discursos de culpabilização da mulher vítima de violência: uma análise dialógica
(Universidade Federal de Lavras, 2026-08-21) Silva, Ângela Furtado Braga Alves; Villarta-Neder, Marco Antonio; https://orcid.org/0000-0003-3857-3720; Lobo, Dalva de Souza; https://orcid.org/0000-0002-9224-5245; Paula, Luciane de; https://orcid.org/0000-0003-1727-0376
Rape culture can be understood as a set of social practices and representations expressed through discourses that, explicitly or implicitly, naturalize, justify, or minimize sexual violence against women. These discursive practices also tend to blame and silence victims of rape, contributing to the impunity of perpetrators and to the potential recurrence of this heinous crime. Grounded in the theoretical framework of Mikhail Bakhtin and the scholars of the Bakhtin Circle, especially Valentin Volóchinov, this dissertation proposes a discursive and dialogic analysis of utterances that blame women who are victims of rape, with emphasis on discourses circulated on social media. Based on the concept of language as a social and ideological practice, this research seeks to understand how such discourses are constructed, legitimized, and disseminated, contributing to the maintenance of rape culture and the perpetuation of gender-based violence. Considering discourse as the materialization of social, ideological, and historical relations, the study analyzes victim-blaming as a discursive effect that shifts responsibility from the perpetrator to the woman, placing her under constant surveillance, suspicion, and social judgment. The corpus of this research consists of utterances posted on the YouTube platform, referring to an alleged case of rape that occurred during a television program involving the guest Otávio Mesquita and the then stage assistant, Juliana Oliveira. These utterances are examined from the perspective of Dialogic Discourse Analysis (DDA), considering the tensions between voices that sustain victim-blaming and those that oppose it, promoting empathy and support. A bibliographical and qualitative methodological approach was adopted because the phenomenon of victim-blaming constitutes a discursive event that is historically situated and shaped by values, ideologies, and social voices. This type of phenomenon requires interpretation rather than measurement. By understanding language as a space of ideological and social disputes, the research contributes to confronting rape culture and the discourses that support it, advocating for a form of education grounded in critical awareness and discursive consciousness as a means to denaturalize discursive practices that blame victims and exonerate aggressors.
dissertação
Percepções de professores da Educação Básica sobre a formação em Pedagogia na modalidade a distância e suas implicações didáticas
(Universidade Federal de Lavras, 2026-08-28) Menezes, Daysiane de Freitas Lopes; Martins, Ronei Ximenes; https://orcid.org/0000-0002-3586-9086; Moreira, Alessandro Messias; https://orcid.org/0000-0001-8120-6219; Lima, Francine de Paulo Martins; https://orcid.org/0000-0002-9646-8235
The growing expansion of undergraduate Pedagogy programs offered through Distance Education has broadened access to teacher education. However, it has also raised questions regarding the quality of teacher preparation, the effective integration of theory and practice, and the readiness of future teachers to address the challenges of Basic Education. In this context, this study sought to answer the following research question: How do Basic Education teachers perceive the training they received in a distance-learning Pedagogy program, and how does this training influence their teaching experiences? Accordingly, the objective of this study was to analyze Basic Education teachers’ perceptions of the training they received and investigate how it influences their teaching experiences. The specific objectives were: (a) to understand the factors that influenced graduates’ decision to pursue an undergraduate Pedagogy degree through Distance Education; (b) to analyze teachers’ perceptions of the training they received and the teaching experiences they had during the program; and (c) to identify the possible impacts of distance education on graduates’ pedagogical practice and teaching experiences. This research is characterized as a descriptive case study with a qualitative approach. Data were collected in two Basic Education schools located in a municipality in the state of Minas Gerais, Brazil, where teachers had graduated from undergraduate Pedagogy programs offered through Distance Education. Five teachers working in the early years of Basic Education participated in the study. The primary data collection instrument was a focus group interview. Data were analyzed using Bardin’s Content Analysis. The findings indicate that the choice of a distance-learning Pedagogy program was mainly motivated by the flexibility and accessibility of this educational modality. Participants acknowledged that their training contributed to the development of pedagogical knowledge, autonomy, and digital technology skills. However, they also pointed out weaknesses in the integration of theory and practice and in the opportunities for practical experiences within school settings. It is concluded that the program contributed to the development of teaching knowledge and professional practice, while highlighting the need to strengthen practical experiences that foster the integration of theory and practice. As an educational product, a Guidelines for the Development of Didactic Sequences in the Early Years of Basic Education was developed.