Growth of cocoa as function of fertigation with nitrogen.

The effect of irrigation and nitrogen fertilization on the growth characteristics of cocoa (Theobroma cacao L.), specifically the clone CCN-51, was evaluate in a field experiment conducted on the period from August 2010 to June 2011 in Jequié city, Bahia State, Brazil. The experimental area, approximately 0.18 ha with the planting of cocoa clonal CCN- 51 in Yellow Oxisol was irrigated drip emitters. The statistical experimental design was randomized blocks with four replications where the factors water level and nitrogen level were factorial combined resulting in the 16 treatments. During the experimental period were measured plant height in plant height and stem diameter. The biometric variables responded to treatments. The water level used in this study negatively affected the plant growth. The nitrogen level used in this study positively influenced the plant growth. The relative growth rate in relation to the plant height and stem diameter, on average, corresponded to about 14% and 15%, respectively

Use of Physical Education Classes as a Didactic Laboratory for Teaching Mathematics: An Example with a Quadratic Function

The research objective of this study was to evaluate the use of Physical Education classes as didactic laboratory for lessons in Mathematics, presenting an alternative way to conduct classes, mainly of quadratic functions, illustrating basic concepts such as graphs plotting and determination coefficients, analyze if such use achieves some of the goals of using a Didactic Laboratory in addition to research ways to interdisciplinary with Physics. Discusses an action in which students work in groups to solve problems proposed based on empirical data obtained through play activities and measures of athletics values practiced by the students allowing may have the opportunity to produce arguments and more meaningful answers, which would improve the overall learning. The athletics and recreational activities are then used as problematic objects both empirically and qualitatively. As a result, it was observed that some of the objectives of a Didactic Laboratory are achieved when using the Physical Education classes and it appears that this feature is much more available in public schools than they are equipped with a science laboratory

Factors controlling spatio-temporal variation in carbon dioxide efflux from surface litter, roots, and soil organic matter at four rain forest sites in the eastern Amazon

[1] This study explored biotic and abiotic causes for spatio-temporal variation in soil respiration from surface litter, roots, and soil organic matter over one year at four rain forest sites with different vegetation structures and soil types in the eastern Amazon, Brazil. Estimated mean annual soil respiration varied between 13-17 t C ha(-1) yr(-1), which was partitioned into 0-2 t C ha(-1) yr(-1) from litter, 6-9 t C ha(-1) yr(-1) from roots, and 5-6 t C ha(-1) yr(-1) from soil organic matter. Litter contribution showed no clear seasonal change, though experimental precipitation exclusion over a one-hectare area was associated with a ten-fold reduction in litter respiration relative to unmodified sites. The estimated mean contribution of soil organic matter respiration fell from 49% during the wet season to 32% in the dry season, while root respiration contribution increased from 42% in the wet season to 61% during the dry season. Spatial variation in respiration from soil, litter, roots, and soil organic matter was not explained by volumetric soil moisture or temperature. Instead, spatial heterogeneity in litter and root mass accounted for 44% of observed spatial variation in soil respiration (p < 0.001). In particular, variation in litter respiration per unit mass and root mass accounted for much of the observed variation in respiration from litter and roots, respectively, and hence total soil respiration. This information about patterns of, and underlying controls on, respiration from different soil components should assist attempts to accurately model soil carbon dioxide fluxes over space and time

Caracterização agronômica de novos genótipos de mamoeiro na Chapada do Apodi.

O mamoeiro (Carica papaya L.) possui expressiva importância econômica para o Brasil, destacando-se como segundo maior produtor mundial. Em 2012 o país produziu 1.517.696 toneladas de mamão (FAO, 2012). No Brasil o mamoeiro é cultivado na quase totalidade do seu território, merecendo destaque os estados da Bahia, Espirito Santo, Ceará e Rio Grande do Norte, que são responsáveis por 87,35% da produção nacional (IBGE, 2013)

Spatial distribution of two symmetric four-wave mixing signals induced by Gaussian beams

We present a theoretical analysis of the spatial shape of two symmetric signals of degenerate four-wave mixing induced by Gaussian beams in a thin sample of two-level atoms. Our calculations take into account the full spatial and spectral dependencies of the relevant nonlinear susceptibilities that govern the two processes. This reveals two interesting effects. The first one is that the total power of incident beams affects the transverse profile of the four-wave mixing signals at the medium exit and their free propagation. The second one is the influence of the spectral characteristics of the medium on the longitudinal profile of both generated signals upon free propagation. We argue that the first effect can be seen as the saturation of the medium in regions of higher intensity, while the second can be understood as the result of a nonlinear contribution to the refractive index inside the atomic medium. These effects can be symmetric between the two signals, with asymmetries induced by different detunings from resonance of the incident fields

Production and nutritive value of piatã grass and hybrid sorghum at different cutting ages.

The influence of cutting age on production and nutritive value of piatã grass (Brachiaria brizantha cv. BRS Piatã) and hybrid sorghum (Sorghum spp. cv. BRS 801) under an integrated croplivestock system was evaluated. The trial was carried out at the Embrapa Beef Cattle (20º27' S; 54º37' W) in Campo Grande, Mato Grosso do Sul State, Brazil, between April and October 2009. Experimental design consisted of randomized blocks with four replicates. Treatments were distributed across a split-plot design, which included three production systems (single piatã grass; single hybrid sorghum; mixed cultivation of sorghum and piatã grass). Half-plots consisted of three forage ages at harvest (with 70, 90 and 110 days after seeding). Variables included agronomical characteristics, productivity and nutrition value. Regardless of the evaluated systems, cutting age affected agronomical characteristics and in vitro digestibility of organic matter (IVDOM). Production was highest (4,048 kg ha-1) within the integrated system. Regardless of cutting age, monoculture sorghum had the highest crude protein level. Results showed that integrated sorghum and piatã grasses were an asset for forage productivity. Forages had higher values in crude protein and in in vitro digestibility of organic matter on the 70th day after seeding.Título em português: Produtividade e valor nutritivo de capim-piatã e sorgo de corte e pastejo em diferentes idades de corte

Variabilidade genética em uma linhagem parcialmente endogâmica de melancia.

A melancia é uma olerícola popular no Brasil, embora a cultivar largamente utilizada, a Crimson Sweet (CS), é suscetível às principais doenças da cultura. Por outro lado, foram encontradas fontes de resistência ao oídio sendo uma delas incorporada na cultivar CS. Linhas homozigotas para cor externa, cor de polpa e formato de fruto, além de teor de açúcarestão disponíveis, porém, ainda estão segregando para características de sementes. Essas características poderão auxiliar como descritores para proteção de uma possível cultivar a ser liberada, desde que estejam em homozigose. Trinta e três progênies provenientes de uma linha experimental resistente ao oídio foram avaliadas quanto às características de fruto e sementes, observando-se que estão relativamente uniformes para teor de açúcar, porém, apresentam variação para peso de 100 sementes e, principalmente, cor da semente, mostrando quatro categorias de cores com indivíduos contrastantes em todas elas. Considerando que poucos genes são responsáveis por essas características, tornam-se necessários alguns ciclos de seleção para se conseguir a homozigose desejada para aceitação comercial da cultivar bem como para a proteção da mesma.Suplemento. Edição dos resumos expandidos do 45. Congresso Brasileiro de Olericultura; 15 Congresso Brasileiro de Floricultura e Plantas Ornamentais; 2. Congresso Brasileiro de Cultura de Tecidos de Plantas, Fortaleza, ago. 2005

Reação à antracnose do feijoeiro-comum em ensaio de campo com inoculação artificial.

O programa de melhoramento do feijoeiro conduzido pela Embrapa e parceiros tem sido bem sucedido no desenvolvimento de linhagens resistentes à antracnose. As cultivares BRS Cometa e BRS Horizonte, as quais possuem grãos do tipo carioca, os de maior aceitação pelo mercado consumidor brasileiro, são exemplos deste sucesso.CONAF

Divergência genética e correlações entre variáveis agroindustriais da população de trabalho de cajuí da Embrapa Meio-Norte.

O trabalho foi realizado na área experimental da Embrapa Meio-Norte, em Parnaíba, PI. A coleção de trabalho é constituída de 11 genótipos coletados em áreas de ocorrência natural da espécie no Estado do Piauí. O experimento foi delineado em blocos completos casualizados, com duas plantas por parcela e quatro repetições. As variáveis avaliadas foram: peso total do fruto, peso do pedúnculo, peso da castanha, diâmetros basal, diâmetro apical, comprimento, firmeza, vitamina C e sólidos solúveis totais. Utilizou-se a análise de agrupamento UPGMA para a separação dos genótipos. A análise da divergência genética permitiu separar os genótipos da coleção de trabalho do cajuí em três grupos geneticamente disjuntos e dentro destes grupos os genótipos: M28 e M21; M23 e M40A e o genótipo M17 podem fazer parte de uma composição de cruzamentos por apresentarem genes complementares para as variáveis consideradas

Mapeamento de hospedeiros de Huanglongbing (Candidatus Liberibacter sp.) no Recôncavo Baiano.

A citricultura brasileira representa importante segmento do agronegócio, sendo São Paulo o estado que detém o primeiro lugar no ranking nacional da produção. Proporcionalmente à pujança da sua citricultura, ele também lidera nas ocorrências fitossanitárias, as quais têm comprometido a rentabilidade do setor.PDF. 158_11