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Dourados, Brazil

Neto C.J.G.,Pesquisador | Hakamada R.E.,University of Sao Paulo | Otto M.S.G.,University of Sao Paulo | Silva S.R.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuaria | Stape J.L.,Gerente de Pesquisa
Scientia Forestalis/Forest Sciences | Year: 2015

The leaf area index (LAI) has been used as a forestry management tool, since it can be used as a reference for the performance of biophysical and physiological processes. Several indirect methods used to determine LAI have been used, but few studies address the calibration of these methodologies at different ages of the forest crop cycle. The LAI-2000 is an indirect method of LAI measurement whose principle is based on the balance between the radiation reaching inside of the canopy and the radiation on the top of it. Another widely used indirect method is the hemispherical photographs that capture the patterns of obstruction and light penetration in the canopy in which the canopy architecture and the foliage area can be quantified. The objective of this study was to compare the indirect methods LAI-2000 and hemispheric photos with the direct method of LAI obtained by destructive sampling of leaf biomass (real LAI), and to evaluate settings and use conditions of the equipments used by both methods. The evaluations were performed in clonal plantations of Eucalyptus grandis x urophylla at different ages and located in southern Bahia, Brazil. The control of the photos exposure was a decisive factor for the use of hemispheric photos. Moreover the opening of the device cover between 270° and 360° and the diffuse cloudy radiation conditions were essential for the proper use of LAI-2000. Both methods showed positive correlations with real LAI, however, there was an underestimation of 68% of the hemispheric photos and 51% of the LAI-2000 in relation to the values obtained by the direct method. Thus, when the interest is the absolute value of LAI, the calibration using destructive methods of leaf biomass is required.

Souza Castro V.D.,Pesquisador | Da Silva L.D.D.F.,State University Londrina | De Souza Fortaleza A.P.,State University Londrina | Brussi Beran F.H.,Discentes de Doutorado | And 6 more authors.
Semina:Ciencias Agrarias | Year: 2013

The objective of this study was to assess the effects of five substitution levels of soybean meal by turnip forage cake in the concentrate, on dry matter intake (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber (NDF) and acid detergent fiber (ADF), pH and ammonia nitrogen (N-NH3) in the rumen liquid and plasmatic urea nitrogen (PUN) in beef steer. The diets wereisoprotein (6.5 % CP) and isoenergetic (50.0% TDN), using in natura sugarcane silage as the only forage (85,5 %DM). Five castrated males were used, 1/2 Simental x Nelore cross, with average weight of 610 kg and 36 months old, all fistulated in the rumen. The different levels of replacement were: 0, 25, 50, 75 and 100%, based on CP responsible of soybean meal of ration. Each experimental period lasted 19 days. The experiment was carried out in a 5×5 latin square experimental design, with five animals and five periods. The potential of dry matter intake (%BW and g/kg BW0,75) of turnip forage cake forage was obtained with 27% of replacement in the protean basis in relation to soybean meal, promoting, a maximum intake of 0,217 kg/animal/day, not proportionating alterations in the ruminal dynamic and in the blood.

Massaro Jr. F.L.,State University Londrina | Da Silva L.D.D.F.,State University Londrina | De Souza Fortaleza A.P.,State University Londrina | Brussi Beran F.H.,Discente de Doutorado | And 6 more authors.
Semina:Ciencias Agrarias | Year: 2013

The objective of this work was to evaluate the effects of Saccharomices cerevisiae and Lactobacillus casei in bovine diets, on dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) intake and digestibility, ruminal pH and ammonia nitrogen (N-NH3) and plasma urea nitrogen (PUN). Rations were isoproteic (13,04% CP) and isoenergetic (66,39% TDN) with sorghum silage used as roughage (50% of DM). Six ruminal-cannulated males,castrated, 1/2 Gir1/2 Holstein crossbred, with average live wight of 317 kg and 24 months old were utilized. Treatments were determined as control (without probiotic addition) and with probiotic, which contained 4,5 × 109 CFU/animal/day of Saccaromyces cerevisiae and 3,1 x 107 CFU/animal/day of Lactobacillus casei. The experiment lasted 38 days, divided in two periods of 19 days. In the present work, the supply of live yeast Saccharomyces Cerevisiae and lactic bacteria Lactobacillus casei had no influence on DM, OM, CP, NDF and ADF intake and digestibility, ruminal pH, ruminal N-NH3 and PUN, indicating that can be used in cattle feed when necessary.

Fontana A.,Federal Rural University of Rio de Janeiro | Pereira M.G.,Federal Rural University of Rio de Janeiro | dos Anjos L.H.C.,Federal Rural University of Rio de Janeiro | Benites V.M.,Pesquisador
Revista Brasileira de Ciencia do Solo | Year: 2010

The information obtained through the humic fractions distribution can be used in brazilian soil studies as a diagnostic attribute or differential characteristic and therefore, contribute to the evolution of Brazilian System of Soil Classification (SiBCS). The objective of this study was to quantify the organic carbon in humic fractions of surface and subsurface diagnostic soil horizons and propose the use in the brazilian system of soil classification. A total of 169 diagnostic horizons distributed between Folistic Epipedon (O hístico), Histic Epipedon (H hístico), Mollic Epipedon (A chernozêmico), Umbric Epipedon (A húmico) and Spodic Horizon (B espódico) were used for this study. These horizons were evaluated for chemical and physical composition. The organic carbon tenors in the fractions: fulvic acids (C-FAF), humic acids (CHAF) and humin (C-HUM) were quantified. C-HAF/C-FAF, C-AE/C-HUM and C-AE/COT (C-AE = C-FAF+C-HAF) ratio and the percentage of each fraction in the total organic carbon (TOC), %FAF, %HAF, %HUM, %AE (Alkaline Extract) were calculated. The Folistic and Histic Epipedon presented predominance of C-HUM, folowed by C-HAF, the Mollic Epipedon presented absolutily dominance of C-HUM, the Umbric Epipedon presented predominance of C-HUM, followed by C-HAF and on Spodic Horizon were observed more expressive of C-HAF or C-FAF. The information of the distribution of humic fractions suggests the use of the following differential characteristics for the families and series levels of SiBCS: stable organic matter (surface mineral horizons): C-AE/C-HUM (≤ 0.5); iluvial organic matter (subsurface mineral horizons): C AE/C HUM (≥ 2.0) and the potential for leaching (system or soil): C-HAF/C-FAF and C AE/C HUM (≥ 1.0).

Leite K.N.,UCLM | Costa R.N.T.,Federal University of Ceara | Crisogtomo J.R.,Pesquisador | Frizzone J.A.,University of Sao Paulo | Marinho A.B.,Institute Desenvolvimento Rural IDR UNILAB
Engenharia Agricola | Year: 2013

Water and fertilizer among the production factors are the elements that most restrict the production of cashew. The precise amount of these factors is essential to the success of the crop yield. This research aimed to determine the best factor-product ratio and analyze technical and economic indicators, of productivity ofthe cashew clone BRS 189 (Anacardium occidentale) to production factors water and potassium. The experiment was conducted from May 2009 to December 2009 in an experimental area of 56.0 m x 112.0 m in the irrigated Curu - Pentecoste, located in the municipality of Pentecoste, Ceará, Brazil. Production factors water (W) and potassium (K) were the independent variables and productivity (Y), the dependent variable. Ten statistical models that have proven satisfactory for obtaining productionfunction were tested. The marginal rate of substitution was obtained through the ratio of the potassium marginal physical product and the water marginal physical product. The most suited model to the conditions of the experiment was the quadraticpolynomial without intercept and interaction. Considering that the price of the water was 0.10 R$ mm -1, the price of the potassium 2.19 R$ kg -1 and the price of the cashew 0.60 R$ kg-1, the amounts of water and K2O to obtain the maximum net income were 6,349.1 L plant-1 of water and 128.7 g plant-1year, -1 respectively. Substituting the values obtained in the production function, the maximum net income was achieved with a yield of 7,496.8 kg ha-1 of cashew.

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