13 resultados para NORTHEASTERN BRAZIL

em Repositório Alice (Acesso Livre à Informação Científica da Embrapa / Repository Open Access to Scientific Information from Embrapa)


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This study aims to evaluate the phenotypical characteristics of bacterial isolates from mulungu (Erythrina velutina Willd.) nodules and determinate their Box-PCR fingerprinting. All bacteria were evaluated by the following phenotypic characteristics: growth rate, pH change, colony color and mucus production. The bacterial isolates able to re-nodulate the original host were also evaluated regarding its tolerance to increased salinity and different incubation temperatures, ability to growth using different carbon sources, intrinsic antibiotic resistance and ?in vitro? auxin biosynthesis. The molecular fingerprints were set up using the Box-PCR technique and the isolates were clustered by their profiles. Among the 22 bacterial isolates obtained, eight were able to re-nodulate the original host. Among the nodule inducing isolates, some were tolerant to 1% of NaCl and 39° C and all of them metabolized the maltose, fructose, glucose, sucrose and arabinose, were resistant to rifampicin and produced auxin. The bacteria showed low genetic similarity among them and reference strains, which indicates the great genetic variability of the isolates. The results of this work are the first reports about the bacterial isolates able to nodulate this species. A more deep study of these bacteria may reveal the existence of isolates tolerant to environmental stresses and suitable as a future mulungu inoculant.

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Limnoperna fortunei (Dunker, 1857) is a small mytilid native to Southeast Asia. It was introduced in South America in early 1990 and has dispersed from Argentina to central Brazil, and until 2014 has been restricted mainly to the Paraná and Uruguay river basins. The present note reports the occurrence of Limnoperna fortunei for the first time in the São Francisco River basin in northeastern Brazil. The establishment of L. fortunei in these regions will require close attention from the government and also by society.

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Vcmax is the rate of maximum velocity of carboxylation of plants and is considered one of the most critical parameters for changes in vegetation in face of global changes and it has a direct impact on gross primary productivity. Physiological processes are considered the main sources of uncertainties in dynamic global vegetation models (DGVMs). The Caatinga biome, in the semiarid region of northeastern Brazil, is extremely important due to its biodiversity and endemism. In a field work realized in an area of preserved Caatinga forest, measurements of carbon assimilation (in response to light and CO2) were performed on 11 individuals of a native species. These results of Vcmax measurements in Caatinga were compared with parameterization of models, revealing that Vcmax is not well adjusted in several DGVMs. Also, the values obtained in the Caatinga field experiments were very close to empirical values obtained in the Northern hemisphere (Austria). These ecophysiological measurements can contribute in understanding of this biome

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Viticulture is an activity of great social and economic importance in the lower-middle region of the São Francisco River valley in northeastern Brazil. In this region, the fertility of soils under vineyards is generally poor. To assess the effects of organic and nitrogen fertilization on chemical properties and nitrate concentrations in an Argissolo Vermelho-Amarelo (Typic Plinthustalf), a field experiment was carried out in Petrolina, Pernambuco, on Syrah grapevines. Treatments consisted of two rates of organic fertilizer (0 and 30 m3 ha-1) and five N rates (0, 10, 20, 40, and 80 kg ha-1), in a randomized block design arranged in split plots, with five replications. The organic fertilizer levels represented the main plots and the N levels, the subplots. The source of N was urea and the source of organic fertilizer was goat manure. Irrigation was applied through a drip system and N by fertigation. At the end of the third growing season, soil chemical properties were determined and nitrate concentration in the soil solution (extracted by porous cups) was determined. Organic fertilization increased organic matter, pH, EC, P, K, Ca, Mg, Mn, sum of bases, base saturation, and CEC, but decreased exchangeable Cu concentration in the soil by complexation of Cu in the organic matter. Organic fertilization raised the nitrate concentration in the 0.20-0.40 m soil layer, making it leachable. Nitrate concentration in the soil increased as N rates increased, up to more than 300 mg kg-1 in soil and nearly 800 mg L-1 in the soil solution, becoming prone to leaching losses.

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In the semi-arid region of northeastern Brazil, the Atriplex plant genus has been efficient in removing salts from soils irrigated with saline wastewater. However, this removal might not be significant compared with the amount of salts added to the soil by the wastewater irrigation. Considering this aspect, the aim of this work was to evaluate the effectiveness of Atriplex nummularia Lindl plants in the remediation of a soil submitted to saline wastewater irrigation. Despite the known inhibition effect of saline wastewater on soil enzyme activity, the cultivation of Atriplex nummularia Lindl maintained the treated soil enzyme activity levels similar to the ones found in natural soils.

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Poincianella pyramidalis (Fabaceae), Schinopsis brasiliensis (Anacardiaceae) and Sideroxylon obtusifolium (Sapotaceae) are native species of the Caatinga vegetation from Northeastern Brazil and have both biological importance and potential economic uses. Little is known about the water uptake and degradation of storage proteins during seed germination of these species. The aim of this study was to evaluate the imbibition and quantify the amount of storage proteins during seed germination of P. pyramidalis, S. brasiliensis and S. obtusifolium. Two lots of S. obtusifolium seeds with different vigour were used. Four replicates of 20 seeds of P. pyramidalis, S. brasiliensis and S. obtusifolium, were sown onto gerboxes with blotting paper soaked in distilled water and incubated during 72, 200 and 624 hours. Before and after imbibition seeds were weighed and frozen at until the sequential extraction and analysis of the seed storage proteins. Based on our results, we conclude that seed germination of P. pyramidalis, S. brasiliensis and S. obtusifolium has a well-defined triphasic imbibition. All storage proteins content of P. pyramidalis and S. brasiliensis seeds degraded along with the seed imbibition. Likewise, the content of albumins, globulins and glutelins decreased as S. obtusifolium seeds absorbed water

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The semiarid region of northeastern Brazil, the Caatinga, is extremely important due to its biodiversity and endemism. Measurements of plant physiology are crucial to the calibration of Dynamic Global Vegetation Models (DGVMs) that are currently used to simulate the responses of vegetation in face of global changes. In a field work realized in an area of preserved Caatinga forest located in Petrolina, Pernambuco, measurements of carbon assimilation (in response to light and CO2) were performed on 11 individuals of Poincianella microphylla, a native species that is abundant in this region. These data were used to calibrate the maximum carboxylation velocity (Vcmax) used in the INLAND model. The calibration techniques used were Multiple Linear Regression (MLR), and data mining techniques as the Classification And Regression Tree (CART) and K-MEANS. The results were compared to the UNCALIBRATED model. It was found that simulated Gross Primary Productivity (GPP) reached 72% of observed GPP when using the calibrated Vcmax values, whereas the UNCALIBRATED approach accounted for 42% of observed GPP. Thus, this work shows the benefits of calibrating DGVMs using field ecophysiological measurements, especially in areas where field data is scarce or non-existent, such as in the Caatinga

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Under land and climate change scenarios, agriculture has experienced water competitions among other sectors in the São Paulo state, Brazil. On the one hand, in several occasions, in the northeastern side of this state, nowadays sugar-cane is expanding, while coffee plantations are losing space. On the other hand, both crops have replaced the natural vegetation composed by Savannah and Atlantic Coastal Forest species. Under this dynamic situation, geosciences are valuable tools for evaluating the large-scale energy and mass exchanges between these diffe rent agro-ecosystems and the lower atmosphere. For quantification of the energy balance components in these mixed agro-ecosystems, the bands 1 and 2 from the MODIS product MOD13Q1 we re used throughout SA FER (Surface Algorithm for Evapotranspiration Retrieving) algorithm, which was applied together with a net of 12 automatic weather stations, during the year 2015 in the main sugar cane and coffee growing regions, located at the no rtheastern side of the state. The fraction of the global solar radiation (R G ) transformed into net radiation (Rn) was 52% for sugar cane and 53% for both, coffee and natural vegetation. The respective annual fractions of Rn used as λ E were 0.68, 0.87 and 0.77, while for the sensible heat (H) fluxes they were 0.27, 0.07 and 0.16. From April to July, heat advection raised λ E values above Rn promoting negative H, however these effects were much and less strong in coffee and sugar cane crop s, respectively. The smallest daily Rn fraction for all agro-ecosystems was for the soil heat flux (G), with averages of 5%, 6% and 7% in sugar cane, coffee and natural vegetation. From the energy balance analyses, we could conclude that, sugar-cane crop presented lower annual water consumption than that for coffee crop , what can be seen as an advantage in situations of water scarcity. However, the replacement of natural vegetation by su gar cane can contribute for warming th e environment, while when this occur with coffee crop there was noticed co oling conditions. The large scale modeling satisfactory results confirm the suitability of using MODIS products togeth er with weather stations to study the energy balance components in mixed agro-ecosystems under land-use and climate change conditions.

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The collection and conservation of the Cucurbita genus in Brazil happened in so dispersed institutions, an assessment of the storage conditions and the genetic diversity is needed, making it possible to identify new priorities for the genus. This work constitutes diagnosis of geographical distribution, storage conditions in situ and ex situ and on genetic diversity of the Cucurbita genus in Brazil. Research was done in herbariums, databases, literature and in situ (expeditions to rural areas and (markets) to map the areas of occurrence of the species. During these expeditions, questionnaires were applied to obtain information about the property and genus Cucurbita. Questionnaires were sent to 173 Brazilian institutions regarding the preservation conditions ex situ. A genetic variability of the Cucurbita genus was found in traditional Brazilian agriculture. Collections must be prioritized in the northern and southern regions (all states); the southeastern region, all states, except Minas Gerais; central-west, in Mato Grosso do Sul and Mato Grosso; the northeastern region, the states of Alagoas, Maranhão, Paraíba, Pernambuco, Piauí and Sergipe. Currently 5.545 entries are being conserved in the Germplasm banks, however, C. pepo, C. ficifolia, C. argyrosperma and wild species are poorly represented. The characterization level of conserved entries is low in the ex situcollections. Participative research projects must be financed as a way to stimulate the farmers to continue planting their local varieties. A coleta e conservação do gênero Cucurbita no Brasil aconteceu de forma dispersa pelas instituições, sendo necessário um diagnóstico sobre as condições de conservação e sobre a diversidade genética, tornando possível identificar novas prioridades para o gênero. Este trabalho realizou diagnóstico sobre distribuição geográfica, condições de conservação in situ e ex situ e sobre diversidade genética do gênro Cucurbita no Brasil. Para mapear as áreas de ocorrência das espécies, foram realizados levantamentos de informações em herbários, banco de dados, literatura e levantamentos in situ (expedições para áreas rurais, feiras livres e CEASAs). Nessas expedições foram aplicados questionários, buscando informações sobre a propriedade e o gênero Cucurbita. Em relação as condições de conservação ex situ, foram enviados questionários para 173 instituições brasileiras. Foi constatado que existe variabilidade genética do gênero Cucurbita na agricultura tradicional brasileira. Devem ser priorizadas coletas nas regiões Norte e Sul (todos os estados); região Sudeste, todos os estados, exceto Minas Gerais; região Centro-Oeste, no Mato Grosso do Sul e Mato Grosso; região Nordeste, os estados de Alagoas, Maranhão, Paraíba, Pernambuco, Piauí e Sergipe. Atualmente estão sendo conservados nos Bancos de Germoplasma 5.545 acessos, no entanto C. pepo, C ficifolia, C. argyrosperma e espécies silvestres estão pouco representadas. É baixa a taxa de caracterização dos acessos conservados nas coleções ex situ. Devem ser financiados projetos de pesquisa participativa como uma forma de estimular e dar condições aos agricultores de continuarem cultivado suas variedades locais.

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The collection and conservation of the Cucurbita genus in Brazil happened in so dispersed institutions, an assessment of the storage conditions and the genetic diversity is needed, making it possible to identify new priorities for the genus. This work constitutes diagnosis of geographical distribution, storage conditions in situ and ex situ and on genetic diversity of the Cucurbita genus in Brazil. Research was done in herbariums, databases, literature and in situ (expeditions to rural areas and (markets) to map the areas of occurrence of the species. During these expeditions, questionnaires were applied to obtain information about the property and genus Cucurbita. Questionnaires were sent to 173 Brazilian institutions regarding the preservation conditions ex situ. A genetic variability of the Cucurbita genus was found in traditional Brazilian agriculture. Collections must be prioritized in the northern and southern regions (all states); the southeastern region, all states, except Minas Gerais; central-west, in Mato Grosso do Sul and Mato Grosso; the northeastern region, the states of Alagoas, Maranhão, Paraíba, Pernambuco, Piauí and Sergipe. Currently 5.545 entries are being conserved in the Germplasm banks, however, C. pepo, C. ficifolia, C. argyrosperma and wild species are poorly represented. The characterization level of conserved entries is low in the ex situcollections. Participative research projects must be financed as a way to stimulate the farmers to continue planting their local varieties. A coleta e conservação do gênero Cucurbita no Brasil aconteceu de forma dispersa pelas instituições, sendo necessário um diagnóstico sobre as condições de conservação e sobre a diversidade genética, tornando possível identificar novas prioridades para o gênero. Este trabalho realizou diagnóstico sobre distribuição geográfica, condições de conservação in situ e ex situ e sobre diversidade genética do gênro Cucurbita no Brasil. Para mapear as áreas de ocorrência das espécies, foram realizados levantamentos de informações em herbários, banco de dados, literatura e levantamentos in situ (expedições para áreas rurais, feiras livres e CEASAs). Nessas expedições foram aplicados questionários, buscando informações sobre a propriedade e o gênero Cucurbita. Em relação as condições de conservação ex situ, foram enviados questionários para 173 instituições brasileiras. Foi constatado que existe variabilidade genética do gênero Cucurbita na agricultura tradicional brasileira. Devem ser priorizadas coletas nas regiões Norte e Sul (todos os estados); região Sudeste, todos os estados, exceto Minas Gerais; região Centro-Oeste, no Mato Grosso do Sul e Mato Grosso; região Nordeste, os estados de Alagoas, Maranhão, Paraíba, Pernambuco, Piauí e Sergipe. Atualmente estão sendo conservados nos Bancos de Germoplasma 5.545 acessos, no entanto C. pepo, C ficifolia, C. argyrosperma e espécies silvestres estão pouco representadas. É baixa a taxa de caracterização dos acessos conservados nas coleções ex situ. Devem ser financiados projetos de pesquisa participativa como uma forma de estimular e dar condições aos agricultores de continuarem cultivado suas variedades locais.

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2016