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    Evaluation of AprX protease effects in milk matrices and its potential applications
    (Universidade Federal de Viçosa, 2026-02-24) Almeida, Lucas Filipe; Alfenas, Gabriela Piccolo Maitan; http://lattes.cnpq.br/6535616137921939
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    How plant-based insecticides can help to control Drosophila suzukii
    (Universidade Federal de Viçosa, 2025-02-27) Araújo, Gabriel Netto; Oliveira, Eugenio E. de; ttp://lattes.cnpq.br/1792712331874137
    Fruticulture faces threats from many phytophagous insects, such as the spotted-wing drosophila, which in the last decade spread over the wold, feeding on think skinned berries and so diminishing production yield. The control of Drosophila suzukii (Diptera) is based on few single-compound legal insecticides, mainly pyrethroids and neonicotinoids, although these are highly toxic for beneficial organisms and natural resources. aiming to understand recent trends in nano-biopesticide development for controlling D. suzukii, chapter 1 is a review on current plant-based alternatives for insecticides used to control D. suzukii, approaching the main botanical families, their lethality or behavioral modulation potential, with gaps and perspectives related to nanotechnology. A total of 712 articles were identified and 31 were selected for this study’s scope. 22 studies evaluated D. suzukii behavioral modulation, and 19 assessed lethality, all caused by plant-based compounds. Although it is understood that essential oils hold great insecticide potential, published data approaching their encapsulation within nanoparticles for controlling D. suzukii. In chapter 2, a prospection over Ruta chalepensis (Rutaceae) essential oil’s toxicity through contact and ingestion exposure against adult Drosophila melanogaster (Diptera) and D. suzukii drosophilids is described. Also, sub- lethal effects on D. melanogaster were evaluated through climbing capacity and activity of antioxidant biomarkers. The potential of R. chalepensis essential oil to inhibit adult emergence from exposed D. suzukii eggs and larvae was also evaluated, indicating development impairment with CL50 = 0.37 ± 0.08 µL/mL. Further, significative difference was found between content of antioxidant biomarkers of adult flies exposed to R. chalepensis essential oil via contact or ingestion in comparison to control, as following data: Superoxide dismutase increased through ingestion and even more through contact, catalase content was slightly increased only through ingestion exposure, glutathione S- transferase activity was increased after contact exposure and decreased upon ingestion exposure, and sulfhydryl content was increased into flies exposed via ingestion and contact. These results indicate that R. chalepensis essential oil is lethal to drosophilids in every life stage, and sublethal exposure of adult flies to this essential oil can cause oxidative stress and affect D. melanogaster adults’ mobility. This dissertationcontributes to drosophilid field control, especially D. suzukii, through gathering and producing knowledge towards plant-based biorational insecticides’ development. Keywords: essential oils; nanotechnology; pest management; Ruta chalepensis; sublethality
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    De efluentes agrícolas a potencial biotecnológico: pGLS, um bacteriófago temperado inovador e resistente com atividade sinérgica e amplas propriedades antibiofilme contra Staphylococcus e Mammaliicoccus
    (Universidade Federal de Viçosa, 2026-02-11) Viana, Vitor Emanuel Lanes; Rossi, Ciro César; http://lattes.cnpq.br/4390760731979737
    A resistência antimicrobiana constitui um dos maiores desafios contemporâneos à saúde pública global, sendo impulsionada pela disseminação de bactérias multirresistentes em ambientes clínicos, agropecuários e naturais. Nesse contexto, Mammaliicoccus sciuri destaca-se como um patógeno oportunista emergente e como importante reservatório de genes de resistência, especialmente aqueles associados à resistência à meticilina, como mecA e mecC. Diante da redução progressiva da eficácia dos antibióticos convencionais, a fagoterapia tem sido resgatada como uma estratégia alternativa promissora para o controle de bactérias resistentes. Este estudo teve como objetivo isolar e caracterizar um bacteriófago oriundo de efluentes de fazenda leiteira capaz de infectar uma cepa multirresistente de Mammaliicoccus sciuri, bem como avaliar seu potencial biotecnológico. O bacteriófago pGLS foi isolado utilizando a cepa M. sciuri GLS3 como hospedeira, apresentando elevada especificidade, eficiência de adsorção e pronunciada estabilidade sob condições ambientais extremas, incluindo ampla faixa de pH, variações de temperatura e exposição à radiação ultravioleta. Apesar de seu espectro lítico restrito, o pGLS demonstrou elevada atividade antibiofilme, sendo capaz de interferir tanto na formação quanto na remoção de biofilmes formados por diferentes espécies da família Staphylococcaceae, incluindo cepas multirresistentes. Adicionalmente, a combinação do pGLS com o antibiótico eritromicina resultou em efeito sinérgico, promovendo redução significativa das concentrações inibitórias mínimas de ambos os agentes e potencializando a inibição da formação de biofilme, o que reforça sua aplicabilidade como terapia adjuvante. A análise genômica revelou que o pGLS é um bacteriófago temperado inédito, com genoma de 41.499 pares de bases, codificando 67 quadros de leitura aberta, dos quais aproximadamente 52% apresentaram função anotada. Não foram identificados genes associados à virulência bacteriana ou à resistência antimicrobiana, reforçando a segurança do pGLS para aplicações futuras. Análises filogenômicas indicaram que o pGLS pertence à classe Caudoviricetes, porém sem classificação definida em níveis taxonômicos inferiores, evidenciando a sub-representação de fagos relacionados em bancos de dados públicos. Em conjunto, os resultados demonstram que o bacteriófago pGLS apresenta elevado potencial biotecnológico, destacando-se por sua atividade antibiofilme, estabilidade ambiental e efeito sinérgico com antibióticos. Este trabalho amplia o conhecimento sobre bacteriófagos associados a Mammaliicoccus sciuri e reforça a relevância da prospecção de fagos ambientais como abordagem inovadora e sustentável para o enfrentamento da resistência antimicrobiana, especialmente em interfaces críticas entre saúde humana, animal e ambiental. Palavras-chave: Staphylococcus; Mammaliicoccus; resistência antimicrobiana; fagoterapia; mecA; genômica
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    Digital decision-making system for controlling the whitefly Bemisia tabaci in tomato crops
    (Universidade Federal de Viçosa, 2025-02-26) Freitas, Damaris Rosa de; Picanço, Marcelo Coutinho; http://lattes.cnpq.br/1730395013873705
    Bemisia tabaci is one of the main tomato pests in the world. Economic damage levels (EIL) vary depending on the cost of controlling the pest, the price of the agricultural product and crop yields. Currently, EILs are determined empirically or using average values of these variables (EILa). The use of this index leads to errors in decision- making. The aim of this study was to develop a digital system for making control decisions for B. tabaci using up-to-date values of the cost of controlling the pest, the price of tomatoes and crop yields. The system created was compared with conventional pest control decision-making plans for Brazil, the USA, Italy, Mozambique and China when using EILa and was determined using prices and yields from the last 20 years. The sampling times and costs of the digital system and the conventional sampling plan in 115 commercial crops in Brazil were also compared. The use of the digital system made personalized decisions for each situation, correcting errors of up to 62.51% and its decisions were quick (2.39 minutes) and low-cost (US$ 2.27 ha-1). Therefore, the digital system is promising for use in tomato plantations for B. tabaci control decision-making, as it enables correct, quick and low- cost decisions. Keywords: Aleyrodidae; Digital agriculture; Application; Decision-making errors; Expert system; Insecticide application technology
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    Leaf morpho-anatomical traits in the modulation of insect-plant interactions: synthesis, validation, and vibroacoustic mechanisms in the tomato-tomato pinworm system
    (Universidade Federal de Viçosa, 2026-02-20) Souza, Diego dos Santos; Guedes, Raul Narciso Carvalho; ttp://lattes.cnpq.br/2776534948642812
    Plant-herbivore interactions are strongly modulated by leaf morpho-anatomical characteristics, influencing everything from host choice to insect biology, development, and feeding behavior. Although plant resistance is traditionally associated with chemical defenses, there is growing recognition that structural leaf traits are important physical modulators of these interactions. However, the literature presents fragmented results, especially regarding the functional role of internal anatomical traits. This thesis aimed to integrate synthetic and experimental evidence to elucidate how leaf morpho-anatomical traits, with an emphasis on internal characteristics, affect insect-plant interactions, particularly involving leafminer insects. In the first chapter, a systematic review with meta-analyses was conducted, following the PRISMA guidelines, encompassing nine decades of publications. After screening, 123 studies were included in the qualitative synthesis and 43 in the meta-analytical synthesis. Most studies focused on insects of the orders Lepidoptera and Hemiptera and on plants of the families Vitaceae, Solanaceae, and Fabaceae. The meta- analyses demonstrated that internal anatomical traits, such as epidermal and palisade parenchyma thickness, consistently reduce herbivore preference, consumption, and performance. However, the literature remains heavily focused on external traits, especially trichomes and cuticle characteristics, while internal traits remain underexplored. Furthermore, many studies evaluate traits in isolation and within a restricted set of biological systems, limiting generalizations about the structural mechanisms of herbivory resistance. In the second chapter, the role of vascular sheath extensions (BSEs), a poorly studied internal anatomical feature, in the interactions between tomato (Solanum lycopersicum) and the tomato leafminer Phthorimaea (= Tuta) absoluta was experimentally investigated. Using isogenic lines with heterobaric (with BSEs) and homobaric (without BSEs) leaves, the effect of this structure on insect consumption, development, and performance was evaluated. The absence of BSEs reduced larval consumption and prolonged development, in addition to resulting in lower pupal mass and delayed adult emergence. Differences in the phytohormone profile, especially jasmonates, indicated that BSEs can modulate physiologicalplant defense pathways. These results demonstrate that BSEs act as morphophysiological modulators of insect-plant interactions, contributing to herbivory resistance. In the third chapter, we evaluated whether BSEs impose immediate biomechanical costs on leafminer feeding behavior. The feeding behavior of P. absoluta larvae on heterobaric and homobaric leaves was analyzed using high- resolution videos and laser Doppler vibrometry, using vibratory emission as a proxy for feeding events. The analyses revealed that mesophyll architecture did not affect chewing motor patterns, indicating that motor control of feeding is highly robust, especially in specialist leafminer insects, and does not undergo immediate changes in response to structural heterogeneity in leaf tissue. Taken together, these findings demonstrate that internal leaf morphoanatomical traits play a relevant role in modulating insect-plant interactions, particularly by affecting consumption and performance throughout development, even if they do not impose immediate biomechanical costs on the feeding behavior of specialized herbivores. The results reinforce the importance of integrating internal anatomical traits and physiological responses in the study of plant resistance in different ecological contexts. This approach contributes to a more comprehensive understanding of the underlying mechanisms that structure insect-plant interactions and can provide support for the development of more sustainable pest management strategies. Keywords: plant-insect interaction; Phthorimaea absoluta; Solanum lycopersicum; functional leaf traits; herbivory; meta-analysis; biotremology; feeding behavior