985 resultados para Espécies Invasoras


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Tropidurus semitaeniatus and Tropidurus hispidus are lizard species that are widely distributed in Brazil. The former is endemic to the Caatingas, where they live in syntopy with the latter, which is distributed in other ecosystems and biomes. In this work, diet was evaluated including seasonal variations as well as foraging behavior, to determine the importance of these factors in the structure of these populations and the coexistence of these species in syntopy. No significant difference was found in diet composition between the two species, although T. hispidus feed on larger preys than do T. semitaeniatus; this fact, along with the different foraging behavior in the rainy season, are ecological factors that contribute to the syntopic coexistence of these species in the Caatinga area studied

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Collembola is one of the most abundant and diverse group of terrestrial arthropods, being at the base of the food chain operating in the decomposition process. They have a wide distribution in the world and can be found in practically all habitats. The knowledge of this distinctive fauna is still deficient in brazilian territory, especially in semi-arid region. The aim of this study was to investigate which climatic variables may act as predictors of species richness, abundance of individuals and compositional structure of the taxocenose of Collembola over 12 months in an area dominated by semi-arid Caatinga vegetation, northeastern Brazil and describe new species of the genus Seira found, more diverse taxon of Collembola in Brazil. Samples were collected in João Câmara, Rio Grande do Norte. Ten plots of 20 x 20 meters were established and the specimens were collected with collection effort of one hour/people using entomological aspirator. The identification and description of the species was carried out by studying the morphology and chaetotaxy. Was performed a multiple regression analysis between species richness and abundance of individuals with climatic variables. A total of 1231 individuals belonging to 15 species, 12 genera and nine families. The greatest richness and abundance of Collembola were found during the rainy season. The genus Seira was the most abundant. Rainfall explained the temporal variation in species richness and abundance of Collembola in the semi-arid region, which is consistent with the biology of these animals. The populations of Collembola showed grouped distribution. Three new species of Seira were described and illustrated and all show similarities with species already registered in the national territory

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In this present work an ethnographic research was performed with 84 native medicinal specimens from the Litoral Norte Riograndense, from which two plants Cleome spinosa Jacq e Pavonia varians Moric were submitted to ethnobotanic, phytochemistry and pharmacologic investigations. Additionally, a phytopharmacological research of the medicinal specimen Croton cajucara Benth ( native plant of the Amazon region of Brazil) was improved. The obtained phytochemical results of the C. spinosa and P. varians showed the presence of flavonoids constituents, among other components. The two flavonoids (2S)-5-hydroxy-7,4 -dimethoxy-flavanone and 5,4 -dihydroxy-3,7,3 -trimethoxy-flavone were isolated from C. spinosa. The antioxidant activity of the hydroalcoholic extracts of C. spinosa and P. varians solubilized in the microemulsion systems SME-1 and SME-4, was evaluated in the DPPHmethod. The used SME systems [obtained with Tween 80: Span 20 (3:1) and isopropyl myristate (IPM)] improved the dissolution of those tested polar extracts, with higher efficacy to the SME-1 system (in which ethanol was included as cosurfactant). The CE50 values evidenced for P. varians were 114 [g/mL (SME-1) and 246 [g/mL (SME-4); for C. spinosa it was 224 [g/mL (SME-1) and 248 [g/mL (SME-4), being the system SME-1 more effective for both tested extracts. The hydroalcoholic extracts of P. varians (HAE-PV) was also submitted to pharmacological screening for antinociceptive activity in animal models. The oral administration of this extract (100, 300 and 1000 mg/kg) inhibited the acetic acid-induced writhing in mice. The higher inhibition (74%) was evidenced to the 1000 mg/kg administered dose. Its effect on the central nervous system (CNS) was investigated by tail flick and formalin-method and reveled that it has negligible antinociceptive action on the CNS. After taking consideration of HAE-PV interaction, Pavonia varians Moric could be used as a potent analgesic agent in case of peripheral algesia, without affecting the CNS. The phytochemical study of the stem bark of Croton cajucara Benth lead to the isolation of 19-nor-clerodanetype diterpenes, as well as to the separation of its fixed oil FO-CC. This non polar oil material reveled to be rich in sesquiterpenes and 19-nor-clerodanes components. The biologic effect of OF-CC was evaluated in the development in vitro of the fungis phytopatogens such as Fusarium oxysporum, Rhizoctonia solani and Sclerotium rolfsii. Significant inhibitory effect of the tested fungis (at 0,2 mg.mL-1 dosage) were comproved. A Mass Spectrometry study of clerodane-type diterpenes was developed in order to identify characteristic fragments on mass spectrometra of both clerodane and 19-nor-clerodane presenting an α,β-insaturated carbonyl moiety at ring A of the decalin-system. For that study, mass spectroscopy data were analysed for 19-nor-clerodanes [trans-dehydrocrotonin (DCTN), trans-crotonin (CTN), cis-cajucarin B (c-CJC-B), and cajucarinolide (CJCR)] and for clerodanes [isosacacarin (ISCR) and transcajucarin A (t-CJC-A)] obtained from the stem bark of C. cajucara, and also clerodane-type from other species. The trans-junction of the enone-system clerodanes was clear correlated with the presence of the characteristic ions at m/z 95, 121 e 205. Meanwhile, the characteristics ions at m/z 122 e 124 were correlated to cis-junction. The trans-junction of the enone-system 19-nor-clerodanes showed characteristics ions at m/z 161, 134 e 121. This study could be successful employed for identification of clerodane constituents from other specimens without any additional spectroscopic analyses, as well as a previously phytochemical analyzes in clerodane project search

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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O objetivo deste trabalho foi avaliar a produtividade de grãos e de forragem do consórcio entre milho e espécies de braquiária (safras de 2008/2009 e 2009/2010), submetidos a doses de nitrogênio em cobertura, em sistema plantio direto. Utilizou-se o delineamento experimental inteiramente casualizado, com quatro repetições, em arranjo fatorial 2x5, com duas espécies de braquiária (Urochloa brizantha 'Xaraés' e U. ruziziensis) e cinco doses de N aplicadas em cobertura: 0, 50, 100, 150 e 200 kg ha‑1. Foram avaliados: leituras indiretas do teor foliar de clorofila (índice de clorofila Falker, ICF), teores de macronutrientes foliares, componentes da produção e produtividade de grãos do milho, e produtividade de matéria seca das forrageiras após o consórcio. Constatou-se que a espécie U. ruziziensis foi a mais competitiva com o milho em consórcio, o que proporcionou menores teores nutricionais e ICF nas duas safras analisadas. O crescimento vegetativo, os componentes da produção e a produtividade de grãos do milho não foram influenciados pelos consórcios. A adubação nitrogenada em cobertura aumenta linearmente o ICF, os teores de N, P e S, bem como os componentes da produção e a produtividade de grãos.

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Modern agriculture is undergoing profound changes, with demands for more efficient management practices in the production systems used in each area. The objectives of this study were: to evaluate the effect of different covering species on a no-tillage system; to find the results of lime application on soil surface after sowing those forage species; measure the effects on soil chemical properties and subsequent effect on corn yield; and to determine the dry matter produced by each species used. The experiment was conducted on November, 2002, in the town of Palotina, Parana State, Brazil. A randomized block design was used, with 4 repetitions, in a 2x6 factorial scheme -two depths of soil sampling (0-10 and 10-20 cm) and six types of forage covering on the soil (Mucuna deeringiana, Crotalaria juncea, Setaria incana, Pennisetum glancum and Eleusine gracilis, as well as a mix of all these species). 3 t ha(-1) of dolomitic limestone were applied in total surface area, without amending. The covering species associated with the surface limestone application showed improvement in soil fertility, mainly in the layer of 10-20 cm, with prominence to Elensine gracilis, Crotalaria juncea and Setaria incana. Eleusine gracilis and Crotalaria juncea featured the largest dry matter production; however, the great amount of straw of Eleusine gracilis damaged the productivity of corn. Grain and corn straw productivity was higher when previously cultivated along with Setaria incana and the mix of forage species covering.

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A considerable number of tree species is the flora in some cases, their fruits and seeds turn out to be good sources of nutrientes. The study aimed to verify the chemical composition of nutrientes in seeds of forest species Pente de Macaco, Flor de Paca, Ita ba, Jatoba and Murici Manso. of forest species of Monkey Comb, Flor de Paca, Ita ba, Jatoba and Murici Manso. The experimental design was randomized with five treatments. Analyses were carried out: moisture content, starch content (mg. g (1)), carbohydrates (mg. g (1)), and proteins (albumin, globulin, prolamin, glutelin) (mg. g (1)) and nutrients (N, P, K, Ca, Mg and S). The results showed that the seeds of Flor de Paca had the highest content of starch and protein of Jatoba is a significant source of carbohydrates and the highest levels of phosphorus, calcium and sulfur. For contents of nitrogen Ita ba showed the highest levels and also obtained satisfactory results for calcium and species Murici Manso had the highest levels of potassium and magnesium.

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Collembola is one of the most abundant and diverse group of terrestrial arthropods, being at the base of the food chain operating in the decomposition process. They have a wide distribution in the world and can be found in practically all habitats. The knowledge of this distinctive fauna is still deficient in brazilian territory, especially in semi-arid region. The aim of this study was to investigate which climatic variables may act as predictors of species richness, abundance of individuals and compositional structure of the taxocenose of Collembola over 12 months in an area dominated by semi-arid Caatinga vegetation, northeastern Brazil and describe new species of the genus Seira found, more diverse taxon of Collembola in Brazil. Samples were collected in João Câmara, Rio Grande do Norte. Ten plots of 20 x 20 meters were established and the specimens were collected with collection effort of one hour/people using entomological aspirator. The identification and description of the species was carried out by studying the morphology and chaetotaxy. Was performed a multiple regression analysis between species richness and abundance of individuals with climatic variables. A total of 1231 individuals belonging to 15 species, 12 genera and nine families. The greatest richness and abundance of Collembola were found during the rainy season. The genus Seira was the most abundant. Rainfall explained the temporal variation in species richness and abundance of Collembola in the semi-arid region, which is consistent with the biology of these animals. The populations of Collembola showed grouped distribution. Three new species of Seira were described and illustrated and all show similarities with species already registered in the national territory

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The anthropical action caused destruction of great part of the Atlantic forest remaining today around 7% to 8% of the original portion. A classical example of the degradation is the situation of the Pau-Brasil (Caesalpinia echinata Lam.) which appellant exploration summarized abruptly decreased the wild occurrence of the species. Besides the economic exploration and the threat of extinction, the plant shows some characteristics that its own physiology makes difficult the survival in natural conditions. For this reason, any strategy developed to conserve it should also guarantee ways for its multiplication. In these conditions, the only reasonable technology is micropropagation in vitro based on immature segments of Catullus (explants or internodes). However, in virtue of the threat of extinction, extractivism and fenology, the disponibility of the sources of explants are reduced. Then, to turn this around, the present research showed the hypothesis that arrange these explants would have as a solution to elaborate a bank of matrixes and the utilization of produced seedlings as source of explant. Then, assuming that the soil is a fundamental element for a good formation of the seedlings, there were tests in a greenhouse on the Laboratory of plant biotechnology at UFRN, from May to June of 2008 that showed the influence of the four different soils on the production of Pau-Brasil. The objective of this work was to make possible the seedlings production of the specie and from them to establish a bank of matrixes as source of explant to guarantee the continuity of the process of micropropagation, contributing with the preservation of the specie

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The Caatinga biome has a high diversity of potential and their conservation constitutes one of the greatest challenges of Brazilian science. The sustainable management of the Caatinga emerges as an alternative that through the formation of systems agrossilvipastoris, enables the use of forest resources sustainably, ensuring their conservation, regeneration and recovery. In RN this technique has been developed mainly in settlements of Agrarian Reform, such as P. A. Moaci Lucena, and their impacts go beyond the environmental aspect and reverberate socially and economically on the quality of life of family farmers. Despite the efficiency of the Sustainable Management of the Caatinga in the conservation of native species, many forests species of this biome faces serious problems of propagation and for this reason have become vulnerable to extinction, as is the case of Mimosa caesalpiniifolia Benth . Thus , it is evident the need to use sustainable alternatives to overcome the difficulties of propagation of this species and enable their replacement in areas where their existence is threatened. The Plant Biotechnology is considered as a promising alternative in this sense, considering that by micropropagation enables the large-scale production of seedlings with high health genetics status. This work has the following objectives: evaluate the perception of family farmers of P. A. Moaci Lucena in relation to social, environmental and economic impacts of the Sustainable Management of the Caatinga and check the conditions of germination and in vitro propagation of Mimosa caesalpiniifolia Benth that enabling the production of seedlings of this specie on a large scale. To achieve the first objective, semi-structured interviews showed that in the perception of farmers PA Moaci Lucena, the Sustainable Management of the Caatinga was responsible for generating many social, environmental and economic impacts that affected directly in the improvement in the quality of life of the families of the Settlement Project Moaci Lucena. Have to achieve the second objective, were investigated the influence of different substrates and concentrations of growth regulator BAP in the germination and shoot induction in vitro of Mimosa caesalpiniifolia Benth. The vermiculite was presented as the most suitable substrate for germination of this species, because it provided a more rapid germination, higher growth rates and higher dry matter accumulation. Regarding micropropagation, the concentration of 17.76 μmol/L of BAP presented a more responsive in relation to multiplication rate and the number of shoots in M. caesalpiniifolia, thus constituting the most suitable concentration for the in vitro propagation of this specie

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The increase in the incidence of fungal infections due to the drug-resistance or to the number of patients with immune alterations such as AIDS, chemotherapy or organ transplantation, has done the research necesseray for new antifungal drugs. The species from Northeastern Brazil may become an important source of innovative natural molecules. To evaluate the antifungal activity of 10 medicinal plants from Northeastern Brazil, traditionally used as antimicrobial agents, 30 crude extracts (CE) were tested in vitro against four standard species of Candida spp. The CE most promising of these plants were evaluated against yeasts of the oral cavity of kidney transplant patients and through a bioassay-guided fractionation. The extracts form leaves of E. uniflora, the stem bark of L. ferrea and leaves of P. guajava showed significant activity against all yeasts evaluated, with MIC values between 15.62 and 62.5 μg/mL. E. uniflora also showed fungicidal properties against all yeasts, especially against Candida dubliniensis. In patients with immune systems compromised, such as transplanted, oral candidiasis manifests mainly due to immunosuppressive therapy, and resistance to conventional antifungals. The CE of E. uniflora presented range of MIC values between 1.95 to 1000 μg/mL, and lower MIC50 and MIC90 values were observed against C. non-albicans. Due the better results, the CE of E. uniflora was elected to performe the bioassay-guided fractionation. Thus it was possible to obtain enriched fractions, which showed good inhibitory ability against ATCC strains of Candida spp. It was also possible to perform experiments to verify the production of biofilm in two strains of C. dubliniensis and action of extracts and fractions on the same. With this, we observed a behavior between the yeast ATCC and clinical isolate. In addition, CE, fractions and subfractions of E. uniflora inhibit planktonic cells to preventing the growth of biofilm. The preliminary chemical characterization of the fractions obtained revealed the presence of polyphenols (especially flavonoids and tannins). Finally, the results suggests that among the plant species studied, E. uniflora showed a pattern very promising as regards the antifungal, requiring further study of purification and structural elucidation of compounds in order to verify that the antifungal effect found can be attributed to a specific compound or some mechanism depends on synergistic the mixture of polyphenols

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As espécies reativas do oxigênio (ERO) são moléculas instáveis e extremamente reativas capazes de transformar outras moléculas com as quais colidem. As ERO são geradas em grande quantidade durante o estresse oxidativo, condição em que são afetadas moléculas como proteínas, carboidratos, lipídeos e ácido nucleicos. Neste trabalho, são discutidos os principais conceitos sobre os radicais livres e as ERO: principais tipos, sua formação e a forma como atuam sobre as estruturas celulares, provocando lesão tecidual significativa. Os principais sistemas de defesa antioxidantes e a influência do aumento na produção dessas ERO no trato respiratório de grandes animais também são discutidos, dando ênfase ao envolvimento das ERO em doenças como a pneumonia em ruminantes e na obstrução recorrente das vias aéreas e a hemorragia pulmonar induzida por exercício em equinos.

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O experimento teve como objetivo avaliar a recuperação de larvas infectantes (L3) de Trichostrongylus colubriformis em Brachiaria decumbens cv. Australiana, Cynodon dactilon cv. Coast-cross e Panicum maximum cv. Aruana. Foram utilizados módulos experimentais constituídos por seis canteiros de 32,4 m² cada, perfazendo dois canteiros por espécie forrageira. Cada canteiro foi dividido em 36 parcelas, de 30 x 30 cm, de forma a permitir seis repetições por espécie e por altura da forragem em cada semana de colheita de material. A sobrevivência larval foi avaliada do meio do verão e até meados do outono, sob o efeito de duas alturas de poda das forragens: baixa, 5 cm e alta, 30 cm. A poda foi realizada imediatamente antes da deposição das fezes contaminadas com ovos de T. colubriformis, obtidos de ovinos, que ocorreu no dia 05/02/ 2004. A colheita das fezes e da forragem foi realizada uma, duas, quatro, oito, 12 e 16 semanas após a deposição das fezes nos canteiros experimentais. A altura da forragem foi medida em cada uma das subdivisões imediatamente antes da colheita. A forragem foi cortada rente ao solo, de uma área delimitada com o auxílio de um círculo de 10 cm de raio. As fezes foram recolhidas manualmente dos canteiros. O número de larvas infectantes recuperado foi muito pequeno em comparação com a quantidade de larvas produzidas nas culturas controle, mantidas no laboratório (máximo de 6,7% no capim Aruana com 30 cm de altura). Arecuperação de L3 das amostras fecais foi maior quando as fezes foram depositadas em meio ao capim alto (com 30 cm - P<0,05). Porém, a recuperação de L3 das forragens foi similar em ambos os cortes. em relação à concentração de L3 (número de L3/kg de matéria seca), não houve diferença entre o corte baixo e alto (P>0,05) em nenhuma das semanas experimentais. Dentre as espécies forrageiras, o capim aruana foi o que, no geral, apresentou maiores concentrações de L3 de T. colubriformis.

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Utilizando técnicas convencionais para estudos histológicos em microscopia de luz com auxílio de luz polarizada, se descreve e compara a anatomia do talo de duas espécies de Parmotrema, Parmotrema consors e Parmotrema cf. reparatum, com rizinas dimórficas e máculas efiguradas, antigamente incluídas em Canomaculina. Os dados obtidos neste estudo mostram que as duas espécies são anatomicamente distintas em relação às características do epicórtex, córtex superior e rizinas. Parmotrema cf. reparatum é anatomicamente similar ao grupo de Parmotrema com máculas reticulares (antigamente incluídas em Rimelia) previamente estudados. Os polissacarídeos típicos do epicórtex e córtex superior do grupo de espécies de Parmotrema com rizinas dimórficas possuem diferenciação histoquímica daqueles mencionados para o epicórtex e córtex superior do grupo de Parmotrema com máculas reticulares.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)