Navegando por Autor "Souza, Daniela Boanares de"
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Item Acumulação de metais em plantas alimentícias cultivadas em solos e tecnossolos metalíferos no Quadrilátero Ferrífero.(2022) Aguiar, Francieli Pianzola Pereira de; Kozovits, Alessandra Rodrigues; Kozovits, Alessandra Rodrigues; Souza, Daniela Boanares de; Sousa, Hildeberto Caldas deA contaminação do solo em todo o mundo é crescente. Elementos não essenciais presentes nos solos podem, de alguma forma, entrar na cadeia alimentar e se tornarem nocivos à saúde. Diante disso, com o objetivo de analisar as respostas de espécies vegetais alimentícias, cultivadas em diferentes naturezas de substratos metalíferos, avaliou-se a concentração e a absorção de elementos potencialmente tóxicos. A área de estudo limitou-se aos municípios de Ouro Preto – com áreas selecionadas de cultivos sobre canga (solo naturalmente metalífero), bem como em Mariana e Barra Longa, em áreas de tecnossolos oriundos da acumulação de rejeitos derivados do rompimento da Barragem de Fundão e em áreas não impactadas pelo rejeito adjacentes a estas, a fim de ser grupo controle. Foram analisadas quimicamente três espécies e os solos onde foram cultivadas. As concentrações dos elementos nas plantas e nos solos foram determinadas via ICP-MS e ICP-OES. Análises granulométricas e de fertilidade também foram realizadas nos solos. Os teores de elementos disponíveis nas partes consumidas das espécies foram comparados aos teores máximos permitidos para o consumo, visando verificar a segurança alimentar desses produtos. As análises de fertilidade demonstraram que o potássio disponível (K) e o magnésio trocável (Mg2+) no solo foram diferentes entre as áreas, no qual os solos não- afetados pelo rejeito apresentam valores maiores em comparação com os solos metalíferos naturais (MN) e afetados pelo rejeito (AF). Na análise geoquímica, a concentração total dos elementos no solo (Mg, P, S, Fe, Mn e Zr) demonstrou diferenças entre as áreas e o solo metalífero natural apresentou valores mais elevados. A cebolinha (Allium fistulosum L.), couve (Brassica oleracea L.) e hortelã (Mentha x villosa Huds) demonstraram maior coeficiente de absorção de macronutrientes, enquanto os elementos tóxicos, quando comparados aos níveis permitidos por instituições de controle de qualidade alimentar, demonstraram valores preocupantes. Maiores concentrações de micronutrientes encontradas na cebolinha e na couve são provenientes do cultivo em áreas não-afetadas pelo rejeito da barragem, enquanto elementos como As, Ni e Pb possuem concentrações maiores nas espécies coletadas em solo metalífero natural. A hortelã cultivada no solo de canga apresentou maiores teores de elementos como o Cu, Fe, Zn, As, Cd, Cr, Ni e Pb no solo metalífero natural. Os resultados gerais indicaram riscos potenciais à saúde no consumo dessas espécies como alimento e uso medicinal.Item Apoplast-symplast compartmentalization and functional traits of iron and aluminum in promeristematic tissues of nematode induced galls on Miconia spp.(2020) Arriola, Igor Abba; Figueiredo, Maurílio Assis; Souza, Daniela Boanares de; França, Marcel Giovanni Costa; Isaias, Rosy Mary dos SantosThe nutritive tissues of galls induced by Ditylenchus gallaeformans (Nematoda) have promeristematic capacity, which may turn these galls into sinks of Al on their Melastomataceae Al-accumulating hosts. Such a sink of Al may affect gall growth and mineral nutrient intake. Based on the fact that galls are good models for plant developmental studies, we aimed to understand how Al-accumulating host plants in the Cerrado environment deal with Al toxicity in subcellular levels. Here, we used the ICP-OES method to check the variations on mineral nutrients, and the morin, hematoxylin, and Prussian blue stainings for Al and Fe histolocalization in galls induced on four Miconia species of the Brazilian Cerrado. We confirmed the new Al-accumulating feature for two Miconia species of the Cerrado environment. Furthermore, we found that Al accumulates in lesser concentrations in gall tissues than in non-galled tissues of the Miconia hosts. Staining methods indicated that the polyphenols avoid Albinding to the apoplast and the nucleolus of the promeristematic cells, and mediated its binding to parenchyma cell walls. As well, we inferred that Fe3þ is transported by xylem and stored in gall parenchyma, where it is reduced to Fe2þ, being available in gall nutritive cells. Our results demonstrated an Al compartmentalization between the apoplast and symplast of the inner cell layers in galls, as well as indicated the phenolics action against Al-toxicity and toward Fe availability for the diet of Ditylenchus gallaeformans.Item Cuticular wax composition contributes to different strategies of foliar water uptake in six plant species from foggy rupestrian grassland in tropical mountains.(2021) Souza, Daniela Boanares de; Bueno, Amauri Pires; Souza, Aline Xavier de; Kozovits, Alessandra Rodrigues; Sousa, Hildeberto Caldas de; Pimenta, Lúcia Pinheiro Santos; Isaias, Rosy Mary dos Santos; França, Marcel Giovanni CostaThe cuticle is the outermost region of the epidermal cell wall of plant aerial organs. The cuticle acts as a two-way lipid barrier for water diffusion; therefore, it plays a vital role in foliar water uptake (FWU). We hypothesised that the chemical composition of the cuticular waxes influences the FWU strategy that plants adopt in a foggy tropical ecosystem. We analysed the leaf cuticular waxes of six plant species known by their different FWU strategies, in both qualitative and quantitative approaches, to test this hypothesis. We also investigated the fine structure of the plant cuticle by scanning electron microscopy. Neither the total wax loads nor the amounts of single wax compound classes correlated to the FWU. In contrast, the qualitative chemical composition of the cuticular waxes was related to the water absorption speed but not to the maximum water absorbed. The presence of wax crystals might interfere with the FWU. Our findings suggest that a complex three-dimensional network of the cuticular compounds contributes to different strategies of FWU in six plant species from foggy tropical mountaintops.Item Foliar water‐uptake strategies are related to leaf water status and gas exchange in plants from a ferruginous rupestrian field.(2019) Souza, Daniela Boanares de; Kozovits, Alessandra Rodrigues; Lemos Filho, José Pires de; Isaias, Rosy Mary dos Santos; Solar, Ricardo Ribeiro de Castro; Duarte, Alexandre Aparecido; Silva, Tiago Vilas Boas da; França, Marcel Giovanni CostaPremise Fog is a frequent event in Brazilian rupestrian field and plays an important role in the physiology of several plant species. Foliar water uptake (FWU) of fog may be fast or slow depending on the species. However, fog water may negatively affect CO2 assimilation. Thus, the interference in the water and carbon balance as a result of different strategies of FWU was evaluated to verify whether fog may mitigate possible water deficit in leaves. Methods Four plant species with different FWU strategies were studied in a ferruginous rupestrian field with frequent fog. Gas exchange and water potential were measured before dawn and at midday during the dry and rainy seasons, separating foggy from non‐foggy days during the dry season. Results The FWU speed negatively influences CO2 assimilation in the dry season, possibly because of its negative relationship with stomatal conductance, since reduced stomatal aperture impairs carbon entrance. Fog presence increased leaf water potential both in early morning and midday during the dry season. However, during the rainy season, the values of leaf water potential were lower at midday, than during the dry season with fog at midday, which favors leaf gas exchanges. Conclusions FWU interferes negatively, but briefly with CO2 assimilation. Nevertheless, FWU prevents water loss through transpiration and increases the water status of plants in the dry season. That is, FWU results in a compensation between CO2 assimilation and foliar hydration, which, in fact, is beneficial to the plants of this ecosystem.Item Imbalance of water potential and photosynthetic efciency in the parasitic relationship between Struthanthus fexicaulis and Baccharis dracunculifolia.(2022) Monteiro, Graziella França; Souza, Daniela Boanares de; Novais, Samuel Matos Antunes de; França, Marcel Giovanni Costa; Itabaiana, Yasmine Antonini; Silva Júnior, Milton Barbosa da; Oki, Yumi; Fernandes, Geraldo Wilson AfonsoHemiparasitic plants can reduce photosynthesis and alter the host plant’s foliar traits. This relationship may be more intense in ecosystems with nutritionally poor soil, such as the campo rupestre, known for its high endemism. This work evaluated the impact of a generalist hemiparasitic species (Struthanthus fexicaulis) on the physiology as well as physical and chemical traits of a native species (Baccharis dracunculifolia) frequently found in the campo rupestre. We planted twenty 60-day-old B. dracunculifolia individuals in a campo rupestre area. Two year after planting, during the 2019 dry season, we evaluated the water potential (Ψw), photosynthetic efciency (PE), specifc leaf area (SLA) and succulence (SU) of parasitized and non-parasitized host plants. These parameters were measured again in the dry season of 2020, when we also measured chlorophyll, nitrogen balance index (NBI) and phenolic content of leaves of the same individuals. Parasitized individuals had a higher Ψw and PE compared to non-parasitized individuals during the most critical period of the day (12:00 pm to 3:00 pm). However, towards the end of the day, parasitized individuals had lower Ψw and PE than non-parasitized ones. There was no efect of parasitism on SLA and SU. Parasitized plants had higher NBI and lower phenolic content than non-parasitized plants. We concluded that S. fexicaulis parasitism interfered in the physiology and chemical leaf traits of B. dracunculifolia. Parasitism, while momentarily increasing the PE and Ψw of parasitized individuals, can cause physiological imbalances, which could negatively afect the development and lead to the death of the host plant over time.Item Pectin and cellulose cell wall composition enables different strategies to leaf water uptake in plants from tropical fog mountain.(2018) Souza, Daniela Boanares de; Ferreira, Bruno Garcia; Kozovits, Alessandra Rodrigues; Sousa, Hildeberto Caldas de; Isaias, Rosy Mary dos Santos; França, Marcel Giovanni CostaLeaf water uptake (LWU) has been observed in plants of different ecosystems and this process is distinct among different species. Four plant species from the Brazilian fog mountain fields were evaluated in order to detect if leaf water uptake capacity is related to the cell wall composition of leaf epidermis. LWU measurements and their relation to anatomical and biochemical traits were analyzed. Cell wall composition was verified through immunocytochemistry using monoclonal antibodies recognizing pectin compounds, and histochemistry with calcofluor white to track cellulose. Differences in LWU among the four species were clearly revealed. Two species presented higher maximum leaf water content and the lowest values of water absorption speed. The other two species presented opposite behavior, namely, low leaf water uptake and the highest values of water absorption speed. The anatomical traits associated with the cell wall composition corroborated the data on the different LWU strategies. The species with abundant detection of cellulose in their epidermal cell walls absorbed more water, but more slowly, while those with abundant detection of pectins absorbed water at a higher speed. These results indicate that cell wall composition regarding pectin and cellulose are significant for water uptake by the leaf epidermis. Pectin provides greater porosity and absorption speed, while cellulose provides greater hydrophilicity and greater water uptake capacity. Current data indicate that the composition of epidermal cell walls is a relevant trait for leaf water uptake.Item Strategies of leaf water uptake based on anatomical traits.(2018) Souza, Daniela Boanares de; Isaias, Rosy Mary dos Santos; Kozovits, Alessandra RodriguesThe ability of leaves to absorb fog water can positively contribute to the water and carbon balance of plants in montane ecosystems, especially in periods of soil water deficit. However, the ecophysiological traits and mechanisms responsible for variations in the speed and total water absorption capacity of leaves are still poorly known. • This study investigated leaf anatomical attributes of seven species occurring in seasonal tropical high-altitude ecosystems (rocky outcrop and forest), which could explain differences in leaf water uptake (LWU) capacities. We tested the hypothesis that different sets of anatomical leaf attributes will be more marked in plant individuals living under these contrasting environmental conditions. Anatomical variations will affect the initial rate of water absorption and the total storage capacity, resulting in different strategies for using the water supplied by fog events. • Water absorption by leaves was inferred indirectly, based on leaf anatomical structure and visual observation of the main access routes (using an apoplastic marker), the diffusion of water through the cuticle, and non-glandular or glandular trichomes in all species. • The results suggest that three LWU strategies coexist in the species studied. The different anatomical patterns influenced the speed and maximum LWU capacity. The three LWU strategies can provide different adaptive advantages to adjust to temporal and spatial variations of water availability in these tropical high-altitude environments.Item The use of nucleation techniques to restore the environment : a bibliometric analysis.(2014) Souza, Daniela Boanares de; Azevedo, Cristiano Schetini deThe population awareness about environmental conservation is raising and this broughtabout an increase in the number of environmental restoration studies. Nucleation is a tech-nique used for environmental restoration, where small nuclei of vegetation are establishedwithin degraded land. The aim of this paper was to evaluate, by doing a bibliometric analy-sis, the tendencies and gaps in the study of environmental restoration using the nucleationtechnique. Data were collected using The Web of Science©and Google Scholar©databases,from 1996 to 2012. Keywords used in the search of papers were nucleation, soil recovery,transposition of soil, bird perches, ecological succession, seed rain, restoration ecology, for-est regeneration, degraded area and natural regeneration. Results showed that the numberof published studies was low, although increasing in the last decade. The majority of thestudies used more than one restoration technique or used natural perches as nuclei. Most ofthe studies were conducted in the Americas and by Brazilian researches. Many studies werenot published as papers in scientific journals, but were available as master thesis or mono-graphs. Natural and artificial perches, soil transposition and natural regeneration were themost successful techniques. The number of nucleation studies must increase and spreadthrough the world, and their results need to be published to help other researches in theenvironmental restoration.