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Sinopse da família Melastomataceae Juss. para o estado do Ceará

2026-05-29T03:37:54Z

Título: Sinopse da família Melastomataceae Juss. para o estado do Ceará Autor(es): Mota, Carlos Adrian Rodrigues Abstract: Melastomataceae is a monophyletic family comprising 173 genera and approximately 5,850 species, of which 1,523 occur in Brazil and 1,008 are endemic. This study aims to assess the actual species richness and distribution of Melastomataceae in the state of Ceará, based on data obtained from biological collections and field expeditions, through the analysis of herbarium specimens, illustrations, photographs, and type material. A total of 50 species and 14 genera were recorded, including nine new species records and three new genus occurrences for the state. Furthermore, field expeditions enabled the recollection of Aciotis annua in Ceará after more than 180 years without records. This study provides taxonomic comments, identification keys, photographic plates of plants in the field, and maps of geographic distribution. Tipo: Dissertação

Interações de micropartículas de TiO2 com os sistemas biológicos Lactuca sativa L., Artemia salina e Danio rerio

2026-05-28T14:40:46Z

Título: Interações de micropartículas de TiO2 com os sistemas biológicos Lactuca sativa L., Artemia salina e Danio rerio Autor(es): Lima, Ana Kamila Medeiros Abstract: Nanostructured materials have revolutionized modern life. Numerous compounds have undergone size reduction processes and have been reintroduced into sectors such as health, cosmetics, food, agriculture, technology, and others. The compound used in this work is titanium dioxide microparticles (TiO2MPs). It is a metal produced on a large scale and used in sunscreen formulations, in food as a colorant, in aquatic depollution strategies, among others. The objective of this work was to characterize the effects of titanium dioxide toxicity on biological systems. The three models chosen were: Lactuca sativa L., Artemia salina, and Danio rerio. Experiments were carried out exposing the models to different concentrations: lettuce to 50 mg.L-1 TiO2MPs, artemia to 12.5, 25, 50, and 100 mg.L-1 TiO2MPs, and zebrafish to 1, 10, and 100 mg.L-1 TiO2MPs. The results were analyzed using conventional optical microscopy, scanning electron microscopy, and transmission electron microscopy. Anatomical and ultrastructural damage confirmed the compound's toxicity to lettuce. In artemia, it caused a high mortality rate in addition to cellular damage at concentrations of 25, 50, and 100 mg.L-1 TiO2MPs. In zebrafish, however, there was no mortality or high rate of deformation. TiO2MPs showed toxicity dependent on concentration, time, and biological model. Even without confirmed absorption, direct contact causes cellular and structural damage in plants and animals. The results highlight the importance of chronic studies under realistic environmental conditions to assess the impact of TiO2MPs on ecosystems and food chains. Tipo: Tese

Microbioma associado à Mimosa tenuiflora (Willd.) Poir. em área suscetível à desertificação da caatinga e o potencial funcional de bactérias endofíticas para a recuperação de áreas degradadas

2026-05-19T12:15:44Z

Título: Microbioma associado à Mimosa tenuiflora (Willd.) Poir. em área suscetível à desertificação da caatinga e o potencial funcional de bactérias endofíticas para a recuperação de áreas degradadas Autor(es): Rocha, Jeanderson da Silva Abstract: Desertification in the Brazilian semiarid region poses a growing threat to Caatinga biodiversity and ecosystem services. Mimosa tenuiflora (Willd.) Poir. (jurema-preta) stands out as a dominant pioneer species in degraded areas and for its contribution to natural regeneration; however, the microbiological mechanisms underlying its resilience remain poorly understood. This study aimed to characterize the bacterial microbiome associated with the rhizosphere and root endosphere of M. tenuiflora in an area susceptible to desertification and evaluate the effect of endophytic bacterial inoculation on seedling early development. To this end, the root bacterial microbiome of M. tenuiflora was characterized for the first time in the municipality of Irauçuba, Ceará state, through amplicon sequencing of the 16S rRNA gene V4 region. Libraries were normalized by rarefaction (60,000 reads/sample) and analyzed for alpha diversity, beta diversity, and taxonomic composition. The rhizosphere exhibited significantly higher alpha diversity than the endosphere, a pattern consistent with progressive host-mediated filtering. Beta diversity analysis revealed significant compositional differentiation between compartments (PERMANOVA: R² = 0.536, p = 0.009), with greater rhizospheric homogeneity and endospheric heterogeneity. At the phylum level, Pseudomonadota dominated the endosphere, while Actinomycetota was more abundant in the rhizosphere. Differential abundance analysis identified 11 significantly enriched genera (p-adj < 0.05, |log2FC| ≥ 2): 10 in the rhizosphere (Conexibacter, Neobacillus, Crossiella, among others) and one in the endosphere (Rhizobium). The endosphere was dominated by the Burkholderia-Caballeronia-Paraburkholderia complex, known for symbiotic nitrogen fixation and multiple plant growth-promoting capabilities, followed by Klebsiella and Mycobacterium. The results reveal functional partitioning between compartments, with endospheric specialization in nutrient provisioning and stress mitigation versus maintenance of rhizospheric diversity related to decomposition and nutrient cycling. In vitro inoculation experiments with M. tenuiflora seedlings demonstrated that the Serratia rubidaea + Citricoccus sp. endophytic consortium promoted increased root growth compared to the control (p.adj < 0.05), confirming the potential of native strains to promote plant growth. This structuring constitutes an adaptive strategy to desertification conditions, explaining the resilience of M. tenuiflora in degraded soils and providing the basis for bioinoculant development and Caatinga ecological restoration strategies. Tipo: Dissertação

Enriquecimento ambiental como ferramenta para o bem-estar do peixe-boi marinho em cativeiro

2026-04-28T12:12:19Z

Título: Enriquecimento ambiental como ferramenta para o bem-estar do peixe-boi marinho em cativeiro Autor(es): Carvalho, Renata Cândido Abstract: The state of Ceará is the portion of the Brazilian coast with the highest record of strandings of Antillean manatees, Trichechus manatus. This relatively high number of strandings is due, at least in part, to the silting up of estuaries and rivers that, under normal conditions, function as a nursery for these animals. Due to these strandings, the NGO Association for Research and Preservation of Aquatic Ecosystems (Aquasis) created a successful preservation program for this species, in which live stranded marine manatees are rescued and taken to rehabilitation, where they receive veterinary care, food, water, spending years in captivity until the moment of release. Although essential for the rehabilitation of these animals, captivity can harm their health or wild instincts, given the routine and predictable access to resources to which they are subject. One way to mitigate these losses is the use of environmental enrichment strategies, which can reduce stereotyped behaviors. In this context, the present study aimed to test whether environmental enrichment improves the well-being of captive manatee. For this, different environmental enrichment techniques were applied to four manatees that were in captivity at Aquasis for rehabilitation (and subsequent release). The pre-enrichment and post-enrichment behavioral budget of these animals was recorded through observations following the scan sampling methodology. From this, it was evident that environmental enrichment alters the behavioral budget of manatees in captivity, with emphasis on the increase in the animals' movement through the enclosure, as well as in foraging behaviors, suggesting an improvement of their well-being. The interval between the animals' meals is the ideal period for the application of environmental enrichment, considering that the animal is active during this period, especially in the morning, before the first feeding. Environmental enrichment can be considered an indispensable strategy for the routine of manatees undergoing rehabilitation. It is recommended that additional studies with different types of enrichment be carried out. Tipo: Dissertação