235 resultados para Environment Effects on Cables
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Dypsis leptocheilos is highly valued as an ornamental palm. Its propagation is done by seeds; however, there is little information about this process. The objective of this work was to study the substrate and temperature effects on the germination of D. leptocheilos seeds. The experiments were carried out at FCAV/UNESP, Campus of Jaboticabal, São Paulo State, Brazil. In order to study the substrate effects, four treatments were arranged (coconut fiber, sand, vermiculite and Plantmax (R)) at 30 degrees C. For the temperature effects, six treatments were performed (temperature at laboratory conditions (21.5 degrees C and 72% RU), 25 degrees C, 30 degrees C, 35 degrees C, 20-30 degrees C and 25-35 degrees C), having the coconut fiber as the substrate. The experimental design was completely randomized, with four replicates of 25 disseminules per plot (seeds with attached endocarp). Water replacement was managed to maintain 100% of the retention capacity of the substrates. The germination tests were observed every two days, and conducted over 148 days for the substrate effects, and over 152 days for the temperature effects, when no more seed germination was noted. In order to determine the germination percentage (% G) and the Germination Speed Index (GSI), the seed was considered germinated when the germinative button appeared. At the end of the experiments, leaf area (cm(2)), root and shoot length (cm), root and shoot dry mass (g) were also obtained. Statistical analysis was performed and means were compared by the Tukey test. Germination rate and speed in coconut fiber was higher at 25 and 30 degrees C. However, when other substrates were tested at 30 degrees C, the highest germination percentage was observed in vermiculite, which also sustained better results for the seed germination and for the characteristics related to shoots and roots.
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Soil acidity is one of the most important factors limiting agricultural production in the tropics. For this reason, the objective of this research work was to evaluate the effects of soil liming on the performance of carambola (Averrhoa carambola) trees. The experiment took place at the Citrus Experimental Station in Bebedouro, state of São Paulo, Brazil. The soil was a Typic Haplustox (V = 26% at the 0- to 20-cm layer) between August 1999 and July 2003. The following doses of limestone were employed: 0, 1.85, 3.71, 5.56, and 7.41 t ha(-1). During 40 months after the experiment was set up, soil chemical attributes were periodically examined. For a period of 2 years, the trees had their leaves analyzed for micro-and macronutrients; their trunk diameter, height, and crown volume measured; and the production of fruits determined. Liming improved in evaluated chemical attributes of the soil: pH, calcium (Ca), magnesium (Mg), BS, V, and hydrogen and aluminium (H + At) from the upper 60 cm of soil when the samples were taken from both the line and between the lines of plants. In the leaves, the levels of Ca and Mg also increased. The highest fruit yields were observed when soil base saturations reached 45% on the lines and 50% between the lines, as well as when foliar levels of 8.0 g of Ca and 4.7 a of Mg per kilogram of leaves were attained.
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Os resíduos vegetais das culturas, ao se decomporem, alteram os atributos químicos do solo e, como consequência, influenciam a produtividade das culturas em sucessão. O objetivo deste trabalho foi avaliar os atributos químicos do solo e a produtividade das culturas de soja, milho e arroz, cultivadas no verão, em sucessão a culturas de inverno em semeadura direta. O experimento foi realizado em Jaboticabal-SP (48 ° 18 ' 58 '' W e 21 ° 15 ' 22 '' S), em um Latossolo Vermelho eutrófico. O delineamento experimental foi em blocos ao acaso, no esquema em faixas, com três repetições. Os tratamentos foram constituídos pela combinação de quatro sequências de culturas de verão (monoculturas de milho e soja e rotações soja/milho e arroz/feijão/algodão) com sete culturas de inverno (milho, girassol, nabo forrageiro, milheto, guandu, sorgo e crotalária). Os cultivos iniciaram-se em 2002. Após o manejo das culturas de inverno e antes da semeadura das culturas de verão do ano agrícola 2006/2007, foram coletadas amostras de solo nas camadas de 0-2,5; 2,5-5,0; 5-10; 10-20; e 20-30 cm. Nas amostras de solo, foram determinados: teores de matéria orgânica, pH, teores de P (resina), K, Ca e Mg trocáveis e acidez potencial (H + Al). As sequências de verão rotação soja/milho e milho em monocultura proporcionaram no solo menores teores de matéria orgânica na camada de 0-10 cm e de P do solo na camada de 0-20 cm. Na sequência de verão arroz/feijão/algodão, maiores teores de K foram proporcionados pelas culturas de inverno crotalária e nabo forrageiro, na camada de 0-10 cm, e milheto, na de 0-2,5 cm. Crotalária, milheto, nabo forrageiro e sorgo, cultivados no inverno, proporcionaram maiores teores de matéria orgânica no solo na camada de 0-30 cm. Maiores teores de P no solo foram proporcionados pela crotalária, na camada de 0-2,5 cm, e pelo nabo forrageiro, na de 0-5 cm. Maiores produtividades de soja, como monocultura de verão, foram obtidas após nabo forrageiro e crotalária e, quando em rotação com milho no verão, após nabo forrageiro, crotalária e milheto. Maiores produtividades de milho foram obtidas após nabo forrageiro, milheto e guandu, e menor produtividade de arroz foi obtida após sorgo.
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Several initiatives, including research and development, increasing stakeholders' awareness and application of legislation and recommendation, have been carried out in Latin America to promote animal welfare and meat quality. Most activities focused on the impact of pre-slaughter conditions (facilities, equipment and handling procedures) on animal welfare and meat quality. The results are encouraging; data from Brazil, Chile and Uruguay showed that the application of the improved pre-slaughter handling practices reduced aggressive handling and the incidence of bruised carcasses at slaughter in cattle and pigs. These outcomes stimulated some to apply animal welfare concepts in livestock handling within the meat production chain as shown by the increasing demand for personnel training on the best. To attend this demand is important to expand local studies on farm animal welfare and to set up (or maintain) an efficient system for knowledge transfer to all stakeholders in the Latin America meat production chains. However, it is clear that to promote the long-term progress in this field is important to deliver practical solutions, assuring that they match the technical and financial conditions of those who are the target of training programs. (C) 2012 Elsevier Ltd. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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We evaluated genetic and environmental factors affecting age at first farrowing of sows in the Brazilian southeast. For this purpose, 466 observations regarding the age at first farrowing were made for Dalland-C40 (c) animals belonging to two herds. The effects of the environmental factors on this trait were assessed by means of a model that included, as random effects, the influence of the sow's father and mother and, as fixed effects, the influence the year of birth, the herd and the birth season, along with the covariable litter size at birth. The variance components were estimated using the derivative-free restricted maximum likelihood method. The estimated mean was 354.8 +/- 25.87 days, with a coefficient of variation of 7.29%. Significant effects on the trait were observed for the herd, the year and the season of birth; but a linear effect of litter size at birth on the age at first farrowing was not observed. The boar did not significantly contribute to the variation occurring among the sows, whereas the sow's mother caused significant variation. The heritability estimate for the age at first farrowing was 0.44 +/- 0.15, which is considered high. We concluded that herd effect and year and season of birth should be taken into consideration for an accurate genetic comparison; consequently, the animals should be joined into contemporary groups.
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O pepino (Cucumis sativus L.) é, dentre os produtos hortícolas, um dos mais visados para o cultivo em estufas no Brasil devido ao ciclo vegetativo curto e ao elevado valor econômico no período da entressafra. Estudou-se, em condições de ambiente protegido, a influência de diferentes cores de cobertura plástica de solo no florescimento e na produção de pepino híbrido 'Yoshinari' enxertado ou não sobre abóbora híbrida 'Ikky'. Os tratamentos de cobertura foram: preto, preto pintado de branco, verde, e sem cobertura. Os tratamentos cobertos com plástico e sem enxertia apresentaram florescimento com distribuição mais uniforme na planta. O número de flores foi superior no tratamento preto/branco enxertado. Para as plantas não enxertadas, todas as coberturas favoreceram o florescimento. A enxertia favoreceu o florescimento somente para os tratamentos com plástico preto ou verde. A fixação dos frutos aumentou pelo uso de cobertura plástica, mas a enxertia não teve influência. A distribuição uniforme do florescimento manteve-se na frutificação apenas para os tratamentos com plantas enxertadas e cobertura do solo com plástico preto ou verde. Tanto o uso de cobertura plástica quanto a enxertia favoreceram a colheita precoce. Os frutos de melhor qualidade e as maiores produções, em número de frutos, foram obtidos nos tratamentos preto e preto/branco, não enxertados. A enxertia 'Yoshinari'/'Ikky' provocou o aparecimento de frutos mais grossos e menores, fora do padrão de comercialização.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Brazil has extensive area with acid soils. Using phosphogypsum and soil acidity tolerant cultivars are alternatives to crop establishment in no-till system without previous limestone incorporation in many agricultural soils of Brazil. However, it remains unknown how phosphogypsum and limestone surface application affects rice (Oryza sativa L.) and common bean (Phaseolus vulgaris L.) nutrition and yield under a no-till system. A field experiment was conducted in a sandy clay loam, kaolinitic, thermic Typic Haplorthox, previously cultivated under conventional tillage, in Botucatu, Sao, Paulo State, Brazil. Treatments included four dolomitic limestone rates (0, 1100, 2700, and 4300 kg ha(-1)), two phosphogypsum rates (0 and 2100 kg ha(-1)), and two upland rice cultivars (Caiapo and IAC 202). in 2002-2003, and two bean cultivars (Perola and Carioca), in 2003-2004. Both amendments were applied on the surface, without soil incorporation. The content of Ca, Mg, and Mn in flag leaves and rice yield increased with limestone surface application. Liming increased the shoot dry matter of IAC 202 rice. Phosphogypsum increased S contents in leaves of both rice cultivars, and resulted in higher grain yield in the Caiapo rice. Liming increased K contents in leaves of both bean cultivars. In the absence of phosphogypsum, liming increased S contents and grain yield of bean. Content of Mg in leaves was reduced by phosphogypsum in lower limestone rates. In phosphogypsum presence, liming reduced Zn contents in leaves and increased bean shoot dry matter. Phosphogypsum increased Ca and S, and reduced Mg contents in bean leaves. Using soil acidity tolerant cultivars promoted higher crop yields in no-till systems establishment, even when the effective soil amelioration had not yet been achieved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Determinou-se a tolerância ao dessecamento de sementes de Archontophoenix alexandrae (Wendl. & Drude) e identificou-se o teste de vigor mais sensível para avaliar a deterioração de sementes nessa espécie. Frutos maduros foram colhidos na coleção de palmeiras do Instituto Agronômico em Campinas. Os frutos despolpados foram transportados em embalagem impermeável para a UNESP em Botucatu, onde as sementes foram secas a diferentes intervalos de tempo. Foram avaliados teor de umidade, germinação, comprimento da plântula e condutividade elétrica. Os resultados sugerem que sementes de A. alexandrae são recalcitrantes, com alta porcentagem de germinação (acima de 67%) quando não desidratadas (47% de umidade). Teores de água inferiores a 31,5% reduziram significativamente a taxa de germinação (<52,5%). Perda total da capacidade germinativa foi observada em sementes com 15,1% de umidade. Dentre os testes de vigor empregados, aquele que avalia a condutividade elétrica da água de embebição foi o mais sensível para a identificação da deterioração da semente em resposta à dessecação progressiva do lote em estudo.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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The Global Positioning System (GPS) transmits signals in two frequencies. It allows the correction of the first order ionospheric effect by using the ionosphere free combination. However, the second and third order ionospheric effects, which combined may cause errors of the order of centimeters in the GPS measurements, still remain. In this paper the second and third order ionospheric effects, which were taken into account in the GPS data processing in the Brazilian region, were investigated. The corrected and not corrected GPS data from these effects were processed in the relative and precise point positioning (PPP) approaches, respectively, using Bernese V5.0 software and the PPP software (GPSPPP) from NRCAN (Natural Resources Canada). The second and third order corrections were applied in the GPS data using an in-house software that is capable of reading a RINEX file and applying the corrections to the GPS observables, creating a corrected RINEX file. For the relative processing case, a Brazilian network with long baselines was processed in a daily solution considering a period of approximately one year. For the PPP case, the processing was accomplished using data collected by the IGS FORT station considering the period from 2001 to 2006 and a seasonal analysis was carried out, showing a semi-annual and an annual variation in the vertical component. In addition, a geographical variation analysis in the PPP for the Brazilian region has confirmed that the equatorial regions are more affected by the second and third order ionospheric effects than other regions.