http://repositorio.ufc.br/handle/riufc/50 Sat, 30 May 2026 10:38:18 GMT 2026-05-30T10:38:18Z http://repositorio.ufc.br/handle/riufc/85870 Título: Análise filogenética de isolados de Fusarium spp. agentes etiológicos da podridão da coroa em banana no Brasil Autor(es): Araujo, Leticia Rejane Lima Abstract: Banana (Musa spp.) belongs to the order Zingiberales, family Musaceae, and genus Musa. Originating from Southeast Asia and the Western Pacific, it has been introduced and widely cultivated in various regions of the world. Currently, it is the most produced fruit globally and the second most consumed, with Brazil ranking as the sixth largest producer. In Brazil, production reached approximately 6.9 million tons in 2024, with a strong emphasis on domestic consumption.Despite its economic importance, banana production faces challenges due to postharvest diseases, which affect fruit quality and lead to economic losses. Crown rot has been identified as one of the main diseases, caused by a complex of fungi, particularly Colletotrichum spp., Lasiodiplodia spp., Verticillium spp., and especially Fusarium spp. The disease typically manifests after fruit ripening, compromising its marketability. Therefore, the objective of this study was to perform molecular, morphological, and pathogenic characterization of Fusarium spp. isolates obtained from different banana cultivars in Brazil. A total of 40 Fusarium spp. isolates were collected from asymptomatic banana hands in 10 municipalities across the states of Ceará, Goiás, and Rio Grande do Norte, Brazil. These isolates were georeferenced and obtained from the cultivars Prata, Nanica, and Grand Naine. The isolates were subjected to morphological analysis, molecular characterization (using TEF1 and RPB2 genes), and pathogenicity tests. Phylogenetic analysis revealed significant species diversity within the following complexes: Fusarium fujikuroi Species Complex (FFSC), Fusarium incarnatum-equiseti Species Complex (FIESC), and Fusarium oxysporum Species Complex (FOSC). Within the FFSC, Fusarium musae was the most prevalent species; within the FIESC, Fusarium sulawesiense and Fusarium pernambucanum were prominent. In the FOSC, Fusarium triseptatum and Fusarium fabacearum were identified. Pathogenicity tests demonstrated that all isolates were capable of causing disease symptoms, with F. triseptatum (FOSC) being the most aggressive. These results highlight the complexity of banana crown rot, with multiple Fusarium species contributing to the disease. Tipo: Dissertação Wed, 01 Jan 2025 00:00:00 GMT http://repositorio.ufc.br/handle/riufc/85870 2025-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/85671 Título: Eficácia de inseticidas contra Aleurodicus cocois Curtis, 1846 (Hemiptera: Sternorryncha: Aleyrodidae) e seletividade a Amblyseius largoensis Muma, 1955 (Mesostigmata: Phytoseiidae) Autor(es): Araújo, Jackson de Lima Abstract: Cashew cultivation, an important sector of Brazilian agriculture, faces phytosanitary challenges that compromise productivity and fruit quality, largely due to the limited availability of registered pesticides and the lack of crop-specific management strategies. Therefore, the development and evaluation of effective alternatives for pest control are essential. Among the main threats is the cashew whitefly, Aleurodicus cocois Curtis, 1846 (Hemiptera: Sternorrhyncha: Aleyrodidae), a sap-sucking insect that colonizes the aerial parts of plants, reduces the photosynthetic area, causes loss of branch vigor and premature leaf drop, ultimately decreasing yield. Among the natural enemies associated with cashew, the predatory mite Amblyseius largoensis Muma, 1955 (Mesostigmata: Phytoseiidae) plays a relevant role in regulating pest populations, contributing to integrated pest management. This study evaluated the efficacy of six neurotoxic insecticides (Abamectin, Acephate, Flupiradifurone, Imidacloprid, Acetamiprid, and Tiametoxam) against A. cocois, considering exposure time, susceptibility by instar, and the determination of lethal concentrations (LC50 and LC90) for the insecticides that showed higher mortality in the initial evaluations. Subsequently, the selectivity of LC90 to the predator A. largoensis was assessed through analyses of survival, prey consumption, oviposition, egg viability, and food conversion efficiency under topical and residual exposure. Bioassays with A. cocois revealed differences among treatments, in which Acephate, Flupiradifurone, and Tiametoxam caused mortality above 80%, whereas Imidacloprid, Acetamiprid, and Abamectin resulted in mortality equal to or lower than 63.5% within the first 24 hours. After 48 hours, all treatments showed increased lethality, and after 72 hours, mortality reached total or near-total levels. Susceptibility was high and uniform across most instars, except for the fourth instar treated with Abamectin, which showed lower mortality and greater variability in response. Concentration-response curves indicated high toxicity of Tiametoxam, Acephate, and Flupiradifurone. Regarding LC90 selectivity to A. largoensis, Acephate was highly toxic under both exposure routes, compromising predator persistence in the agroecosystem. Tiametoxam, although not causing high mortality, altered biological parameters, reducing oviposition, prey consumption, and egg viability. In contrast, Flupiradifurone showed high selectivity, not affecting survival, reproduction, or food conversion efficiency, with reduced egg viability only under residual exposure. These findings indicate compatibility of Flupiradifurone and partial compatibility of Tiametoxam with A. largoensis, demonstrating their potential for use in integrated pest management programs in cashew cultivation. Tipo: Tese Wed, 01 Jan 2025 00:00:00 GMT http://repositorio.ufc.br/handle/riufc/85671 2025-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/85568 Título: Alterações fisiológicas em plantas de coqueiro provocadas por Raoiella indica Hirst e a endoterapia como alternativa para seu controle Autor(es): Oliveira, Felipe Silva Abstract: Raoiella indica is an exotic and invasive mite species in the Americas. Knowledge about the basic (ecological) and applied (management) aspects of this species is still scarce. This is the first study to investigate not only the use of endotherapy to control R. indica in coconut plants, but also the potential physiological changes in the host plant due to R. indica attack. Coconut plants were subjected to three distinct treatments: control (no phytosanitary treatment), endotherapy (abamectin injection into the plant stem), and spraying (abamectin spraying directed at the leaflets). Plant leaflets were evaluated for R. indica infestation (number of motile forms/leaflet) monthly and until the infestation level was reestablished during the endotherapy treatment. Additionally, physiological parameters were measured on the leaflets collected in each treatment at two different time points (one in the rainy season and the other in the dry season). The results of this study demonstrated that: (i) endotherapy with the acaricide abamectin was effective in reducing R. indica populations; (ii) the interval between abamectin acaricide applications via endotherapy can reach 10 months (300 days); (iii) abamectin applications every 2 months via spraying of the plant canopy can contribute to reducing R. indica populations; (iv) the main physiological changes in coconut plants mediated by R. indica attack are observed in the net photosynthetic rate, stomatal conductance, and transpiration; and (v) physiological changes vary according to environmental conditions (rainy and dry seasons). Tipo: Dissertação Sun, 01 Jan 2023 00:00:00 GMT http://repositorio.ufc.br/handle/riufc/85568 2023-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/85333 Título: Práticas agronômicas aplicadas a cultura do hibisco: estratégias de manejo em função do potencial produtivo Autor(es): Nunes, Liliane Ribeiro Abstract: Hibiscus sabdariffa cultivation presents advantages ranging from production to consumption, however, in view of scarce research, the phytotechnical aspects of the crop are still poorly understood, which often makes greater investments in its production unfeasible. Considering the influence of good agronomic practices on optimizing crop productivity, this study aimed to: 1- Establish the ideal spacing for hibiscus cultivation based on growth and productivity results; 2- Determine whether the different doses of biofertilizer used and the practice of apical pruning affect the biometric and physiological aspects of the plant H. sabdariffa, as well as verify whether these factors may directly influence crop productivity. The treatments of six distinct spacings were applied for the evaluation of variables and determination of productivity. The spacing was chosen according to general evaluations of the results and adapted to the crop. Thus, five different doses of foliar fertilization were applied in the second test, and the practice of topping was carried out in half of the experiment to evaluate new results and determine best practices. The studies revealed that hibiscus undergoes changes when different spacings are applied in its cultivation. In view of the significant height results when the plant was grown at wider spacings. In addition, wider spacings also contributed to a gradual increase in the number of structures at stage 1 (closed green flower bud structure), stage 2 (closed reddish flower bud structure), number of flowers and fruits. As well as calyx and capsule structures, which were also positively influenced under these same conditions. For productivity, expressive numbers were observed at reduced spacings, though not significant. The continuation of the study showed that the number of branches was significantly affected by fertilization levels, without the topping technique. Significant responses were observed for stage 1, dry mass of calyces and capsules. The 0,5 g/L fertilizer dose was the most responsive when associated with the topping technique. For productivity, no significant differences were observed. Tipo: Tese Mon, 01 Jan 2024 00:00:00 GMT http://repositorio.ufc.br/handle/riufc/85333 2024-01-01T00:00:00Z