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1.
Bull Environ Contam Toxicol ; 110(1): 18, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36538116

RESUMEN

Germination and post-seminal development are important stages for the establishment of plants and for determining their tolerance to diesel oil. Diesel-tolerant species can contribute to the recovery of contaminated areas, and leguminous plants are promising in the treatment of contaminated soil through nitrogen fixation. This study identified the effects of diesel oil-contaminated soil on the germination and seedlings of the leguminous species Mimosa bimucronata, M. flocculosa, and M. scabrella var. aspericarpa. The experiment comprised two treatments contaminated (4% concentration) and uncontaminated soil and was performed in a greenhouse for 90 days, with evaluations 30, 60, and 90 days after sowing. Germination was not affected, but most root and aerial system parameters were statistically lower in contaminated soil, indicating low initial development potential in soil contaminated with diesel oil. Moreover, the negative effects increased with higher exposure time to the contaminant.


Asunto(s)
Fabaceae , Mimosa , Contaminantes del Suelo , Biodegradación Ambiental , Germinación , Suelo , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis
2.
Front Microbiol ; 9: 2211, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30356683

RESUMEN

The fungal genus Fonsecaea comprises etiological agents of human chromoblastomycosis, a chronic implantation skin disease. The current hypothesis is that patients acquire the infection through an injury from plant material. The present study aimed to evaluate a model of infection in plant and animal hosts to understand the parameters of trans-kingdom pathogenicity. Clinical strains of causative agents of chromoblastomycosis (Fonsecaea pedrosoi and Fonsecaea monophora) were compared with a strain of Fonsecaea erecta isolated from a living plant. The clinical strains of F. monophora and F. pedrosoi remained concentrated near the epidermis, whereas F. erecta colonized deeper plant tissues, resembling an endophytic behavior. In an invertebrate infection model with larvae of a beetle, Tenebrio molitor, F. erecta exhibited the lowest survival rates. However, F. pedrosoi produced dark, spherical to ovoidal cells that resembled muriform cells, the invasive form of human chromoblastomycosis confirming the role of muriform cells as a pathogenic adaptation in animal tissues. An immunologic assay in BALB/c mice demonstrated the high virulence of saprobic species in animal models was subsequently controlled via host higher immune response.

3.
Braz. arch. biol. technol ; Braz. arch. biol. technol;54(6): 1379-1387, Nov.-Dec. 2011. ilus
Artículo en Inglés | LILACS | ID: lil-608451

RESUMEN

The effect of soil polluted by diesel oil on the germination of seeds and the growth of Schinus terebinthifolius Raddi seedlings was analyzed at different times after contamination of the soil. The experiments were conducted under greenhouse conditions, with four treatments and five repetitions. The four treatments included: soil contaminated 30 (T30), 90 (T90) or 180 (T180) days before planting as well as a non-polluted soil (T0) (control). Soil saturated to 50 percent of its maximum retention capacity (MRC) was contaminated with diesel oil at a rate of 92.4 mL per kg. The germination rate and germination speed index (GSI) were significantly affected only in T30. The development of the plants was affected significantly in all the treatments, with reductions of biomass and eophyll area. It could be concluded that diesel oil significantly affected the germination, GSI and seedling growth of S. terebinthifolius, but the toxic effect decreased over the time.

4.
Braz. arch. biol. technol ; Braz. arch. biol. technol;53(2): 311-318, Mar.-Apr. 2010. tab, ilus
Artículo en Inglés | LILACS | ID: lil-546561

RESUMEN

The present work aimed at regenerating plants of Eucalyptus camaldulensis from the cotyledonary explants and describing the anatomy of the tissues during callogenesis and organogenesis processes, in order to determine the origin of the buds. The cotyledonary leaves of E. camaldulensis were cultured in Murashige and Skoog (MS), WPM and JADS media supplemented with 2.7 µM NAA and 4.44 µM BAP. The best results for bud regeneration were obtained on MS and WPM media (57.5 and 55 percent of calluses formed buds, respectively). Shoot elongation and rooting (80 percent) were obtained on MS/2 medium (with half-strength salt concentration) with 0.2 percent activated charcoal. Acclimatization was performed in the growth chamber for 48 h and then the plants were transferred to a soil:vermiculite mixture and cultured in a greenhouse. Histological studies revealed that the callogenesis initiated in palisade parenchyma cells and that the adventitious buds were formed from the calluses, indicating indirect organogenesis.


Este trabalho teve como objetivo a obtenção de plantas de Eucalyptus camaldulensis a partir de folhas cotiledonares e o estudo da anatomia dos tecidos durante a calogênese e organogênese para determinar a origem das gemas. Folhas cotiledonares foram cultivadas em meios de cultura MS, WPM e JADS suplementados com 2,7 µM de ANA e 4,44 µM de BAP. Os melhores resultados para a regeneração de gemas foram obtidos com os meios MS e WPM. Para o alongamento e enraizamento, o meio de cultura MS/2 contendo 0,2 por cento de carvão ativado apresentou-se eficiente para ambas as etapas. A aclimatização foi realizada mediante a abertura dos frascos na sala de crescimento por 48 horas, seguido da transferência para casa-de-vegetação com nebulização intermitente. Estudos histológicos foram conduzidos e revelaram que a calogênese teve início nas células do parênquima paliçádico e que as gemas adventícias formaram-se a partir dos calos, indicando a organogênese indireta.

5.
Biota neotrop. (Online, Ed. port.) ; 9(3): 215-222, July-Sept. 2009. ilus, tab
Artículo en Portugués | LILACS | ID: lil-578539

RESUMEN

Foi realizado o estudo florístico das macrófitas do Município de General Carneiro, localizado no sul do Estado do Paraná, entre as coordenadas 26º 19' 37"/ 26º 26' 40" S e 51º 26' 51"/ 51º 19' 14" W. Os locais de coleta foram as fazendas São Pedro, São Pedro II, Santa Cândida e Lageado Grande, entre os Rios São Pedro, São João, São Manoel, Iratim, Lajeado Grande e Neno. Com a finalidade de se conhecer a flora dos rios e lagoas da região foram realizadas coletas aleatórias das macrófitas entre 2004 e 2006. Os exemplares encontram-se depositados no herbário UPCB e MBM. Registraram-se 45 famílias, 42 de angiospermas, 70 gêneros e 117 espécies. Os ambientes aquáticos são caracterizados floristicamente pelas Cyperaceae, representada por 22 táxons, o que significa cerca de 21 por cento de todos os táxons encontrados, seguidos pelas Poaceae (8), Asteraceae (7) e Polygonaceae (6). Dentre as espécies registradas podemos destacar o primeiro registro para o estado de Lilaeopsis minor Prez-Mor., Apiaceae.


A floristic study of macrophyte communities was conducted at General Carneiro township, situated in Southern Parana State, among 26º 19' 37"/ 26º 26' 40" S and 51º 26' 51"/ 51º 19' 14" W. Samples were collected at São Pedro, São Pedro II, Santa Cândida and Lageado Grande farms, between the rivers São Pedro, São João, São Manoel, Iratim, Lajeado Grande and Neno, in order to study the flora of the rivers and ponds in this region. Macrophyte samples were randomly collected between 2004 and 2006 and registered in the UPCB and MBM herbaria. A total of 45 families was found, 42 of them being angiosperms, 70 genera and 117 species. The aquatic environments are floristicaly characterized by Cyperaceae, represented by 22 taxa, what means approximately 21 percent of all the encountered taxa, followed by Poaceae (8), Asteraceae (7) and Polygonaceae (6). Among the registered species we can highlight the first record in this state of Lilaeopsis minor Prez-Mor, Apiaceae.

6.
Ann Bot ; 104(5): 1011-5, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19567417

RESUMEN

BACKGROUND AND AIMS: Microsporogenesis in monocots is often characterized by successive cytokinesis with centrifugal cell plate formation. Pollen grains in monocots are predominantly monosulcate, but variation occurs, including the lack of apertures. The aperture pattern can be determined by microsporogenesis features such as the tetrad shape and the last sites of callose deposition among the microspores. Potamogeton belongs to the early divergent Potamogetonaceae and possesses inaperturate pollen, a type of pollen for which it has been suggested that there is a release of the constraint on tetrad shape. This study aimed to investigate the microsporogenesis and the ultrastructure of pollen wall in species of Potamogeton in order to better understand the relationship between microsporogenesis features and the inaperturate condition. METHODS: The microsporogenesis was investigated using both light and epifluorescence microscopy. The ultrastructure of the pollen grain was studied using transmission electron microscopy. KEY RESULTS: The cytokinesis is successive and formation of the intersporal callose wall is achieved by centrifugal cell plates, as a one-step process. The microspore tetrads were tetragonal, decussate, T-shaped and linear, except in P. pusillus, which showed less variation. This species also showed a callose ring in the microsporocyte, and some rhomboidal tetrads. In the mature pollen, the thickening observed in a broad area of the intine was here interpreted as an artefact. CONCLUSIONS: The data support the view that there is a correlation between the inaperturate pollen production and the release of constraint on tetrad shape. However, in P. pusillus the tetrad shape may be constrained by a callose ring. It is also suggested that the lack of apertures in the pollen of Potamogeton may be due to the lack of specific sites on which callose deposition is completed. Moreover, inaperturate pollen of Potamogeton would be better classified as omniaperturate.


Asunto(s)
Polen/ultraestructura , Potamogetonaceae/ultraestructura , Microscopía Electrónica de Transmisión , Polen/crecimiento & desarrollo , Potamogetonaceae/crecimiento & desarrollo
7.
Sci. agric. ; 62(3)2005.
Artículo en Inglés | VETINDEX | ID: vti-439983

RESUMEN

Attempts to meet produces market demand are not always followed by research reports showing the impact of novel, intensive cropping systems on the environment, human and animal health, and eventual chemical and structural changes of plants. This work carries a comparative evaluation of the morphology and anatomy of cherry tomato fruits obtained from organic, conventional and hydroponic cropping systems. Fruits were collected at the free market in the greater Curitiba, Paraná, Brazil. For each culture method, 50 fruits their weight, diameter and volume measured. For the anatomical analysis, samples of the pericarp of ten fruits were excised and embedded in glycol methacrylate; 6-mm cuts were then obtained, stained with toluidine blue, and mounted on permanent glass slides. The anatomical analysis and illustrations were performed in Olympus and Zeiss photonic microscope. Samples obtained from the organic cropping system presented the highest mass, diameter, volume and density. The pericarp of fruits, obtained from the conventional cropping system presented larger but less abundant cells in comparison to the pericarp of the hydroponic and organic-produced fruits.


A ciência agrícola buscou novas formas de cultivo para atender às exigências de mercado e dividiu-se em três grandes vertentes: os sistemas de cultivo orgânico, convencional e hidropônico. Todavia, esses avanços nem sempre foram acompanhados por pesquisas que objetivassem apontar o impacto de uma nova técnica agrícola sobre o ambiente, a saúde humana e animal e aos próprios vegetais em seus aspectos químicos e estruturais. Este trabalho tem por objetivo o estudo comparativo da morfo-anatomia do fruto do Lycopersicon esculentum var. cerasiforme (Duval) A. Gray, cultivado nos sistemas orgânico, convencional e hidropônico. Os frutos foram coletados no comércio varejista da Região Metropolitana de Curitiba, Paraná, Brasil. Para cada cultivo foram analisados 50 frutos. Cada fruto foi pesado e teve o diâmetro e volume medidos. Para análise anatômica foram retiradas amostras do pericarpo de dez frutos, que foram embebidas em glicol metacrilato, seccionadas com 6 mm de espessura, coradas com azul de toluidina e montadas em lâminas permanentes. A análise anatômica e as ilustrações foram feitas em microscópio fotônico Olympus e Zeiss com câmara fotográfica acoplada. As amostras obtidas pelo sistema de cultivo orgânico apresentaram maior massa, diâmetro, volume e densidade. O pericarpo, dos frutos do cultivo convencional, apresentou células maiores e em menor número em relação ao pericarpo dos frutos hidropônicos e orgânicos.

8.
Sci. agric ; 62(3)2005.
Artículo en Inglés | LILACS-Express | VETINDEX | ID: biblio-1496550

RESUMEN

Attempts to meet produces market demand are not always followed by research reports showing the impact of novel, intensive cropping systems on the environment, human and animal health, and eventual chemical and structural changes of plants. This work carries a comparative evaluation of the morphology and anatomy of cherry tomato fruits obtained from organic, conventional and hydroponic cropping systems. Fruits were collected at the free market in the greater Curitiba, Paraná, Brazil. For each culture method, 50 fruits their weight, diameter and volume measured. For the anatomical analysis, samples of the pericarp of ten fruits were excised and embedded in glycol methacrylate; 6-mm cuts were then obtained, stained with toluidine blue, and mounted on permanent glass slides. The anatomical analysis and illustrations were performed in Olympus and Zeiss photonic microscope. Samples obtained from the organic cropping system presented the highest mass, diameter, volume and density. The pericarp of fruits, obtained from the conventional cropping system presented larger but less abundant cells in comparison to the pericarp of the hydroponic and organic-produced fruits.


A ciência agrícola buscou novas formas de cultivo para atender às exigências de mercado e dividiu-se em três grandes vertentes: os sistemas de cultivo orgânico, convencional e hidropônico. Todavia, esses avanços nem sempre foram acompanhados por pesquisas que objetivassem apontar o impacto de uma nova técnica agrícola sobre o ambiente, a saúde humana e animal e aos próprios vegetais em seus aspectos químicos e estruturais. Este trabalho tem por objetivo o estudo comparativo da morfo-anatomia do fruto do Lycopersicon esculentum var. cerasiforme (Duval) A. Gray, cultivado nos sistemas orgânico, convencional e hidropônico. Os frutos foram coletados no comércio varejista da Região Metropolitana de Curitiba, Paraná, Brasil. Para cada cultivo foram analisados 50 frutos. Cada fruto foi pesado e teve o diâmetro e volume medidos. Para análise anatômica foram retiradas amostras do pericarpo de dez frutos, que foram embebidas em glicol metacrilato, seccionadas com 6 mm de espessura, coradas com azul de toluidina e montadas em lâminas permanentes. A análise anatômica e as ilustrações foram feitas em microscópio fotônico Olympus e Zeiss com câmara fotográfica acoplada. As amostras obtidas pelo sistema de cultivo orgânico apresentaram maior massa, diâmetro, volume e densidade. O pericarpo, dos frutos do cultivo convencional, apresentou células maiores e em menor número em relação ao pericarpo dos frutos hidropônicos e orgânicos.

9.
Braz. arch. biol. technol ; Braz. arch. biol. technol;47(3): 339-346, July 2004. ilus, tab
Artículo en Inglés | LILACS | ID: lil-363412

RESUMEN

Plantas recém germinadas de acácia negra (Acacia mearnsii De Wild.) foram inoculadas com a bactéria Rhodococcus fascians e cultivadas in vitro. Galhas cobertas por folhas apareceram na altura do nó cotiledonar em 75% das plantas infectadas. As galhas foram separadas das plantas e cultivadas num meio de cultura contendo os sais do meio MS (Murashige e Skoog, 1962) reduzidos a 3/4, as vitaminas do mesmo meio, 2% de sacarose e um antibiótico (cefalotina), adicionado ou não de 0,2% de carvão ativo. Estudos histológicos realizados entre o sexto e o vigésimo segundo dia depois da inoculação, revelaram a presença de centros meristemáticos novos, primeiro nas regiões axilares, em seguida nos pecíolos e limbos dos folíolos ao redor do meristema apical. Aproximadamente 37% das galhas desenvolveram um broto na presença de cefalotina.

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