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Mateus G.P.,Agencia Paulista de Tecnologia dos Agronegocios | Crusciol C.A.C.,São Paulo State University | Borghi E.,Embrapa Pesca e Aquicultura | Pariz C.M.,São Paulo State University | And 2 more authors.
Pesquisa Agropecuaria Brasileira | Year: 2011

The objective of this work was to evaluate the effect of nitrogen fertilization management on single and intercropped sorghum with Marandu and Mombaça grasses, and to determine the forage dry weight yield in the 2003/2004 and 2004/2005, in a no. tillage system. The experimental design was in randomized block, in a 3×5 factorial arrangement, with four replicates. The treatments consisted of three sorghum cropping systems (single and intercropped with Marandu and Mombaca grasses in the rows) and five nitrogen fertilizer managements: 30-70; 70-30; 50-50; 100-0; and 0-100 kg ha -1 of N, applied at sowing and topdressing, respectively. Intercropping did not affect sorghum nutrition nor grain yield. Only in the first growth season, the 50-50 kg ha -1 of N splitting increased grain yield. Straw management interfered in sorghum establishment during the second growth season and decreased grain yield. The highest rates of N topdressing increased forage dry weight yield of Marandu grass and, applied at sowing, N highest rates increased this attribute in Mombaca grass.


Crusciol C.A.C.,São Paulo State University | Mateus G.P.,Agencia Paulista de Tecnologia dos Agronegocios | Pariz C.M.,São Paulo State University | Borghi E.,Embrapa Pesca e Aquicultura | And 2 more authors.
Pesquisa Agropecuaria Brasileira | Year: 2011

The objective of this work was to evaluate the effect of the intercropping with Marandu grass on the nutrition and yield of sorghum hybrids with contrasting-cycle, in no-tillage system. It was used a randomized block experimental design in a factorial arrangement (2×2), with six replicates. The treatments consisted of two sorghum hybrids with contrasting cycles (P8118, medium cycle; and P8419, early cycle) and two crop systems (single and intercropped with Marandu grass in the seed row), with the seeding done in the early December. Nutrition, agronomic traits, production components, and dry matter and grain yields of the sorghum hybrids were evaluated. Except for potassium and sulphur, the leaf contents of the other nutrients were appropriate in all treatments for sorghum cropping. The hybrid P8118 had the highest grain yield and, after the intercropping, it contributed for the highest forage dry matter yield of Marandu grass in the cut performed in October. The intercropping of contrasting-cycle sorghum hybrids and Marandu grass does not affect sorghum nutrition, and dry matter and grain yields, in comparison with the single cropping, irrespectively of the hybrid cycle.


Viola M.R.,Federal University of Tocantins | Avanzi J.C.,Embrapa Pesca e Aquicultura | de Mello C.R.,Federal University of Lavras | Lima S.O.,Federal University of Tocantins | Alves M.V.G.,Federal University of Tocantins
Pesquisa Agropecuaria Brasileira | Year: 2014

The objective of this work was to determine rainfall erosivity values and to generate its spatial-temporal distribution maps in the state of Tocantins, Brazil. Pluviometric historical series from 97 rain gauges were analyzed, covering the period from 1985 to 2009. Erosivity was estimated by equations in which the independent variable was the average monthly rainfall or the Fournier rainfall index (Rc). Geostatistics was applied for mapping erosivity both monthly and annually. Annual erosivity values varied between 6,599 and 14,000 MJ mm ha-1 h-1, with peak in December when it reached values up to 2,800 MJ mm ha-1 h-1 per month. From May to September, erosivity values had lower than the critical one, considered 500 MJ mm ha-1 h-1 per month. Three priority regions were identified for soil and water conservation planning activities: mid-west region of the state, in the neighborhood of Cantão State Park, with greatest erosivity; northern region of the state, especially during the first quarter of the year; and southern region of the state, in the fourth quarter.


Cardoso D.P.,Federal University of Tocantins | Silva M.L.N.,Federal University of Lavras | De Carvalho G.J.,Federal University of Lavras | De Freitas D.A.F.,Federal University of Säo João del Rei | Avanzi J.C.,Embrapa Pesca e Aquicultura
Revista Brasileirade Ciencias Agrarias | Year: 2013

Soil cover crops may provide improvement and restructuring of chemical and physical soil properties, reduce the soil resistance to penetration and increase soil permeability, thus reducing water erosion. Therefore, this work aimed to evaluate the potential of cover crops in the reconditioning the chemical and physical properties of soil. The experiment was conducted in Lavras in the region south of Minas Gerais State, and the cover crops were planted on a distrophic Hapludult. The treatments consisted of Crotalaria juncea L. (sunn hemp), Canavalia ensiformis DC. (jack-bean) and Pennisetum sp Rich (pearl millet), grown in between-rows with spacings of 0.25 and 0.50 m. The chemical and physical properties analysed were pH, macronutrients, soil organic matter, bulk density, total porosity, microporosity, macroporosity, saturated hydraulic conductivity, soil temperature and moisture, aggregate stability and soil penetration resistance. There was influence of cover crops on the potassium and phosphorus availability in soil, but other chemical properties were not modified. The bulk density, total porosity, micro and macroporosity were not changed after cultivation of cover crops, regardless of row length used. The cover crops reduced the soil penetration resistance values for non-restrictive to root growth to 0.25 m depth.


Silva T.S.C.,University of Sao Paulo | Moro G.V.,Embrapa Pesca e Aquicultura | Silva T.B.A.,University of Sao Paulo | Dairiki J.K.,Embrapa Amazonia Ocidental | Cyrino J.E.P.,University of Sao Paulo
Aquaculture Nutrition | Year: 2013

Knowledge on apparent digestibility coefficients (ADC) is necessary to maximize the feed efficiency, thus lessening dietary nutrient and energy losses. This study tasks the determination of apparent digestibility of selected feedstuff to striped surubim Pseudoplatystoma reticulatum, a carnivorous, South American catfish of economic importance for fisheries and fish culture alike. Juvenile striped surubim (82.4 ± 17.7 g and 23.0 ± 1.6 cm) was distributed in 21 cylindrical, plastic cages (80 L), housed in seven 1000 L feeding tanks under constant water flow and aeration and conditioned to a two daily meals (20h00m and 22h00m) feeding regimen on a practical, reference diet (RD) (460.0 g kg-1 crude protein (CP); 19.23 kJ g-1 gross energy (GE)]. Test diets were obtained by adding of 1 g kg-1 chromium III oxide and 300 g kg-1 of one the following feedstuffs: fish meal (FM), meat and bone meal (MBM), poultry by-product meal, feather meal, blood meal, soybean meal, wheat bran, corn and corn gluten meal to the RD. After the last daily meal, fish were transferred to cylindrical, conical-bottomed aquaria (200 L) under aeration and continuous water exchange, coupled to refrigerated plastic bottles for faeces collection by sedimentation. Best ADC of protein (99.36%) and energy (86.25%) were recorded for poultry by-product meal and MBM, respectively, which are thus deemed ideal surrogate feedstuffs to FM in the formulation and processing of diets for striped surubim. © 2012 John Wiley & Sons Ltd.


Moro G.V.,Embrapa Pesca e Aquicultura | Silva T.S.C.,Embrapa Agropecuaria Oeste | Zanon R.B.,University of Sao Paulo | Cyrino J.E.P.,University of Sao Paulo
Aquaculture Nutrition | Year: 2016

Carbohydrates and lipids are the major and cheaper non-protein energy sources for fish diets. This study aimed at determining ideal relationship between dietary starch and lipids and their influence on digestive enzyme profile of juvenile dourado. Trials were set up in a closed-loop system with controlled temperature, dissolved oxygen, pH and total ammonia. Experimental extruded diets formulated to contain different starch (St) to lipids (Lip) ratio (St : Lip = 0 : 1, 0.3 : 1, 0.7 : 1, 1.0 : 1, 1.4 : 1, 2.0 : 1, 2.3 : 1 to 3.3 : 1) were fed to juvenile dourado (3.34 ± 0.16 g) and stocked into 30 polyethylene tanks (330 L, 30 fish per tank) in a completely randomized design with unbalanced repetition (n = 3 or 4), in two daily meals (1000 and 1530) until satiation, for 95 days. Dietary starch contents higher than 145.2 g kg-1 (St : Lip > 1.0 : 1.0) hampered the performance of fish, but, paradoxically, the inclusion of carbohydrates in the diet elicited better utilization of dietary protein and energy by the species. Fish adapted digestive enzyme profile to dietary starch contents through increasing secretion of alkaline proteases and non-specific lipases, but secretion of amylase was not altered. Physiological responses show the limitation of species on the use of dietary carbohydrates. © 2015 John Wiley & Sons Ltd


Simon J.,Embrapa Pesca e Aquicultura | Angelocci L.R.,University of Sao Paulo
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2014

The all-wave radiant energy absorbed by the canopy (Rnc) of trees is one of the main variables of interest in water studies and crop growth of woody species, but its direct determination is not an easy task, being limited to experimental work. Scanning the top of trees along plant hedgerows by moving net radiometers around them is a technique that renders possible spatiotemporal integration of Rnc values, allowing the tests of physico-mathematical models and establishing of correlations of Rnc with routine measurements of incoming solar radiation (Rg) and grass net radiation (Rng). Integrated values measured by this technique in a stretch of rows of a coffee plantation and an acid lime orchard were correlated with Rng and Rg. For the coffee crop, linear and quadratic polynomial equations fitted well for the relationship of Rnc with Rg and Rng for autumn, winter and spring in 15 min, hourly and diurnal time-scales, but for the summer only in the diurnal scale this occurred. For the lime orchard, good fits were obtained in the three timescales in the winter, but only for the diurnal timescale in the summer. © 2014, Departamento de Engenharia Agricola - UFCG/Cnpq. All rights reserved.


Paiva A.J.,University of Sao Paulo | da Silva S.C.,University of Sao Paulo | Pereira L.E.T.,University of Sao Paulo | Caminha F.O.,University of Sao Paulo | And 2 more authors.
Scientia Agricola | Year: 2011

Knowledge regarding morphogenetic characteristics has contributed to the understanding of plant responses to variations in climatic conditions and management practices. However, the original framework has been developed for temperate grass species, and indicates no ontogenetic effect on the expression of morphogenetic traits. Similar information for tropical grass species is scarce, but not less important. This experiment aimed at evaluating the influence of tiller age on the morphogenetic characteristics of continuously stocked marandu palisadegrass swards maintained at 30 cm and fertilized with nitrogen (N). Treatments corresponded to three nitrogen application rates (150, 300 and 450 kg ha -1 of N) plus the control (no fertilization) and were assigned to experimental units (1,200 m 2 paddocks) according to a complete randomized block design, with four replications. The following response variables were measured during autumn/winter (Jun. to Jul. 2007) and summer (Feb. to Mar. 2008): leaf appearance rate (LAR), leaf elongation rate (LER) and the age profile of the tiller population. In general, LAR and LER were higher on young (< 2 months old) relative to mature (2 to 4 months old) and old (> 4 months old) tillers during both autumn/winter and summer. During autumn/winter swards were mainly comprised of old tillers (> 4 months old), the opposite happening during summer, when they were mainly comprised of young tillers. Overall, there was no N effect within tiller age categories. Tiller age was an important factor interfering with the morphogenetic responses of marandu palisadegrass, indicating that there is an ontogenetic effect on plant morphogenesis that should be considered further in future studies of this nature.


PubMed | Embrapa Tabuleiros Costeiros, Tiradentes University, Uninorte Manaus, Embrapa Pesca e Aquicultura and 3 more.
Type: | Journal: Brazilian journal of biology = Revista brasleira de biologia | Year: 2016

The present study evaluates the influence of anesthesia on the parasitic fauna of monogenea fish parasites, as its intensity and viability. Two experiments were conducted: Evaluation of an anesthetic method by sprinkling eugenol directly on gills and evaluation of monogenea motility and viability; Comparison of immersion and directly sprinkling on the gills with benzocaine and eugenol followed by evaluation on parasite intensity. The results suggest that the anesthetic sprinkling didnt interfere in the parasite motility, morphology and body surface integrity analyzed by fluorescence method. The monogenean intensity in the gills was lower in fish anesthetized by immersion method compared to the sprinkling method and the control group. This method of anesthesia can be used in parasitological studies.


Soratto R.P.,São Paulo State University | Fernandes A.M.,São Paulo State University | Pilon C.,University of Arkansas | Crusciol C.A.C.,São Paulo State University | Borghi E.,Embrapa Pesca e Aquicultura
Pesquisa Agropecuaria Brasileira | Year: 2013

The objective of this work was to evaluate the common bean response to N application timing, under no-tillage system, after single corn or intercropped with palisade grass. A randomized complete block experimental design was used in a split-plot arrangement, with four replicates. Plots consisted of: single corn crop or corn intercropped with palisade grass, in two summer cropping seasons precedent to common bean sowing. Subplots consisted of: 100 kg ha-1 N application in three times-before sowing, at sowing, and at side-dressing-and a control treatment without N application. Nitrogen fertilization on common bean increased leaf-N content, the number of pods per plant, and grain yield (33% in the average application timing), only in the cropping after single corn. By providing large mass production and by N cycling, the cultivation of palisade grass intercropped with corn reduced N requirement of common bean in succession, in comparison to previous sole corn cultivation. Early N application before or during common bean sowing time provides grain yield similar to the observed one in the side-dressing application.

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