https://repositorio.ufba.br/handle/ri/1017 Mon, 04 May 2026 07:55:17 GMT 2026-05-04T07:55:17Z https://repositorio.ufba.br/handle/ri/44109 Título: Avaliação da morfogênese para a conservação ex situ de cactáceas micro endêmicas da Chapada Diamantina (BA) Autor(es): Souza, Isabela Primeiro Orientador: Schnadelbach, Alessandra Selbach Abstract: Cacti have great commercial relevance, with distribution nearly restricted to the Americas, and the elevated threats of extinction of species from this botanical family raise some concerns about their conservation. Ex situ conservation techniques can promote long-term viability of explants for propagation that serves both conservation and industrial purposes, however they demand a delicate balance of techniques and a deep study regarding the species' specific morphophysiological behavior. This dissertation aims to understand the morphophysiological behavior in the regeneration of different kinds of explants from Micranthocereus flaviflorus (Buining & Brederoo) P.J. Braun & Esteves and Micranthocereus alvinii (M. Machado & Hofacker) N.P. Taylor & M. Lowry. After inducing the material, callus portions of 0.01 cm², 0.04 cm², or 0.16 cm² of both species were submitted to culture in half-strength MS, 1.5% sucrose, and pH ranging from 5.6 to 5.8, supplemented with various combinations and concentrations of the auxins 2.4-D and NAA and the cytokinins BAP and KIN, and part of the samples were dry-weighted every 15 days for a total of 90 days. All tested callus sizes were able to regenerate. The highest mean was observed for treatments containing 5 μM 2.4-D with 5 μM KIN for M. alvinii and 5 μM 2.4-D with 10 μM BAP for M. flaviflorus. There was a significant increase in dry weight from day 75, which continued until day 90 for M. flaviflorus, unlike M. alvinii. Treatments containing 5 μM 2.4-D with 10 μM KIN for M. alvinii and 5 μM 2.4-D with 10 μM BAP for M. flaviflorus fit linear equations and may extend the growth phase beyond the 90 days tested. We also tested five different explants under suitable combinations of growth regulators to induce shoot or callus formation. For M. flaviflorus, a single areole was able to regenerate, producing either shoots or calluses, while for M. alvinii, although a single areole was able to produce calluses, the smallest explant capable of producing shoots was a quarter of a transversal section with one row of areoles. For the establishment of a cell suspension, 0.16 cm² portions were inoculated in test tubes or Erlenmeyer flasks subjected to a 16 h light/day cycle or complete darkness. In all treatments, we successfully obtained cell suspensions, and there was no interference from the container type or light exposure. This study contributes to the development of basic techniques for future application of cryopreservation practices in isolated cactus tissues, aiming to assist with the ex situ conservation of species in this botanical family. Editora / Evento / Instituição: Universidade Federal da Bahia Tipo: Dissertação Wed, 18 Jun 2025 00:00:00 GMT https://repositorio.ufba.br/handle/ri/44109 2025-06-18T00:00:00Z https://repositorio.ufba.br/handle/ri/44005 Título: Taxonomia integrativa dos complexos de espécies de Dendropsophus haddadi e D. oliveirai (Amphibia, Anura, Hylidae) Autor(es): Pita, Ícaro Pinto Primeiro Orientador: Napoli, Marcelo Felgueiras Abstract: The genus Dendropsophus Fitzinger, 1843 constitutes a monophyletic group of small anurans, comprising more than 100 species distributed in nine groups. Among these is the group of D. decipiens, currently composed of seven species occurring from southern to northeastern Brazil. Despite the monophyletic support of the group, it presents internal relationships that lack resolution. In addition to the existence of succinct original descriptions and potential mixed type series, significant genetic and morphological variability was observed among the taxa, indicating the presence of diversity not yet described in the group. This dissertation aimed to perform a taxonomic analysis of the D. decipiens group, combining molecular, morphometric, and bioacoustic data, as well as a rudimentary characterization of morphology and color patterns. The results revealed a taxonomic complexity greater than expected: 25 genetic lineages were identified, ten of which are novel and not previously explored in the literature. Seven correspond to nominal species and fifteen were classified as confirmed candidate species. The study revealed a gradient of morphological and acoustic crypticity among the taxa, reinforcing the need for multiple tools for species delimitation within the group. This work provides a characterization of the lineages found and re-evaluates the status of the nominal species, contributing significantly to the knowledge of the cryptic and systematic diversity of Dendropsophus. Editora / Evento / Instituição: Universidade Federal da Bahia Tipo: Dissertação Fri, 28 Nov 2025 00:00:00 GMT https://repositorio.ufba.br/handle/ri/44005 2025-11-28T00:00:00Z https://repositorio.ufba.br/handle/ri/43809 Título: Diversidade morfológica e molecular de Syconidae Poléjaeff, 1883 (Porifera, Calcarea) do Brasil Autor(es): Mattedi, Alice Primeiro Orientador: F. Cavalcanti, Fernanda Abstract: Syconidae Poléjaeff, 1883 was proposed to group calcareous sponges that exhibit a syconoid aquiferous system and lack a cortex, which may or may not have tufts of diactines. Currently, it comprises Sycetta Haeckel, 1872 and Sycon Risso, 1827. The identification of its species is challenging due to morphological similarity in skeletal composition, and phylogenetic analyses have indicated that neither of these two genera is monophyletic. Sycetta has few known species, but several new species have been described over the years for Sycon, which is common in various regions of the world and in scientific collections. To date, no revisionary studies have been conducted on the family or its genera, despite incomplete descriptions, distribution patterns inconsistent with what is expected for Calcarea, and a lack of information on intraspecific morphological variability. In light of this, the aim of this study was to investigate the diversity of Syconidae in Brazil (southwestern Atlantic ocean), using an integrative approach combining morphological and molecular data (LSU region C). For this purpose, type materials of the species already known from Brazil were redescribed, and new specimens – both from scientific collections and recent samplings – were examined. A new species of Sycetta, Sycetta papillata sp. nov., was described based on collection material gathered decades ago. This is the first record of the genus in the southwestern Atlantic. Detailed images of the morphology of these individuals and a comparative table of Sycetta species were also provided, contributing to future taxonomic identifications. Regarding Sycon, the types of six of the seven species found in Brazil were redescribed, and the first photographic records of the skeletons of some of these species were made. Additionally, three new species were described. DNA sequences were made available, including those from the holotypes of Sycon avus Chagas & Cavalcanti, 2017 and S. bellum Chagas & Cavalcanti, 2017. These data allowed confirmation of the conspecificity of specimens and exploration of their geographic distributions – interestingly, the DNA sequence of one of the new species grouped with others available in GenBank from Hawaii. It was not possible to analyze in deeply the specimens corresponding to those sequences, but preliminary analyses do not rule out that the morphology may indeed be similar. Other noteworthy findings include the discovery of spined diactines in S. avus and the suspicion that S. vigilans Sarà & Gaino, 1971 does not occur in Brazil. Although species within Sycon and Sycetta are morphologically very similar, some morphological characteristics, such as the shape of the spicules and the type of insertion of diactines on the body surface, can be used to differentiate the species analyzed here. Thus, both morphological and molecular data were essential for understanding the diversity of Syconidae found in Brazil. The results presented here may encourage future studies on the revision of its genera and represent an important step forward in the complex systematics of this family. Editora / Evento / Instituição: Universidade Federal da Bahia Tipo: Dissertação Thu, 29 May 2025 00:00:00 GMT https://repositorio.ufba.br/handle/ri/43809 2025-05-29T00:00:00Z https://repositorio.ufba.br/handle/ri/43683 Título: Efeitos do óleo essencial de Elionurus muticus (Spreng.) Kuntze na indução anestésica e no manejo de tilápia do Nilo em diferentes pH da água Autor(es): Patrick, Jordan Correia da Silva Primeiro Orientador: Carlos, Eduardo Copatti Abstract: This study evaluated essential oil from Elionurus muticus (EOEM) as an anesthetic in juvenile Nile tilapia (Oreochromis niloticus) under different water pH conditions. Two experiments were conducted. In Experiment 1, fish (25 g) were exposed to EOEM concentrations ranging from 10 to 600 µL L⁻¹ at pHs 5.5, 7.0, and 8.5 to determine induction and recovery times. In Experiment 2, fish (70 g) were transferred from water at pH 7.0 to waters at pHs 5.5, 7.0, or 8.5, anesthetized (600 µL L⁻¹) or not, and sampled after 0 and 1 h for hematological and plasma biochemical analyses. The 600 µL L⁻¹ concentration was effective for anesthesia, with the shortest induction and recovery times at pH 7.0. Acidic and alkaline conditions prolonged recovery, indicating higher physiological stress. In Experiment 2, after 1 h, non-anesthetized fish at pH 5.5 exhibited elevated hemoglobin levels, while anesthetized fish at pH 8.5 had a reduced hematocrit. Leukocyte and heterophil counts were highest at pH 7.0, especially in anesthetized fish. Anesthesia at pH 7.0 reduced plasma total protein and albumin levels. Hyperglycemia was observed in unanesthetized fish at pH levels of 5.5 and 8.5. Plasma total cholesterol, high-density lipoprotein, and low density lipoprotein levels were higher in the interaction between anesthesia and pH 8.5. These results demonstrate that water pH has a strong influence on the anesthetic efficacy and physiological responses of Nile tilapia exposed to EOEM (600 µL L⁻¹). Optimal performance occurred at pH 7.0, while acidic and alkaline (mainly) conditions increased recovery time and hematobiochemical stress. Editora / Evento / Instituição: Universidade Federal Da Bahia Tipo: Dissertação Fri, 17 Oct 2025 00:00:00 GMT https://repositorio.ufba.br/handle/ri/43683 2025-10-17T00:00:00Z