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Registros recuperados: 67 | |
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Pereira,Hamilton Seron; Leão,Anabelisa Ferreira; Verginassi,Adriana; Carneiro,Marco Aurélio Carbone. |
The aim of this study was to evaluate the N losses due to volatilization at different rates of common urea, polymer coated urea and urease inhibitor-treated urea in the out-of-season corn, using semi-open static collectors. The treatments consisted of N levels on side-dressing fertilization with urea in different treatments: (a) control (without N), (b) urea 40 kg ha-1 N, (c) urea 80 kg ha-1 N, (d) polymer coated urea 40 kg ha-1 N, (e) polymer coated urea 80 kg ha-1 N and (f) urea with the urease inhibitor (UI) N 80 kg ha-1 N. The results showed that the treatments with polymer coated urea and with urease inhibitor-treated urea reduced the volatilization of N around 50 % compared to common urea, either in the first and the second N side-dressing... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nitrogen; Nitrogen fertilization; Slow release. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832009000600017 |
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Megda,Michele Xavier Vieira; Mariano,Eduardo; Leite,José Marcos; Megda,Marcio Mahmoud; Trivelin,Paulo Cesar Ocheuze. |
Abstract: The objective of this work was to evaluate the effect of the application of ammonium chloride as a nitrogen source for sugarcane (Saccharum sp.) on the development of the crop’s shoot and roots during two consecutive cycles. The experiment was conducted on a Typic Hapludox in the first and second sugarcane ratoons. The treatments consisted of four N doses (50, 100, 150, and 200 kg ha-1) applied as ammonium chloride (NH4Cl), besides a control, without the application of N. The increase in the NH4Cl dose increased in up to three times soil electrical conductivity in the layer of 0.0-0.2 m, with a consequent increase in the concentration of chlorine in leaves. In the second cycle, the contents of chlorine increased in 1,900 mg kg-1 in the leaf with... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Saccharum; Electrical conductivity; Nitrogen fertilization; Root system; Stalk productivity. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2019000102100 |
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Vieira,Michele Xavier; Trivelin,Paulo Cesar Ocheuze; Franco,Henrique Coutinho Junqueira; Otto,Rafael; Faroni,Carlos Eduardo. |
The great difficulty of incorporation of N fertilizers into the "green sugarcane" system causes concern and since urea is the most commonly used source, there is the risk of loosing NH3 through volatilization. For this reason, a field experiment was undertaken (in a Hapludox Typic) with the objective of evaluating the agronomic efficiency of ammonium chloride on stubble of the second ratoon (SP89 1115), as well as its residual effect on the subsequent cycle (third ratoon). The experimental design was randomized blocks with four replications. Treatments consisted of three N rates (60, 120 and 180 kg ha-1 N) in the form of NH4Cl, in addition to a control treatment without the addition of N fertilizer. The ratoon cane of the second cutting was harvested in... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Saccharum spp; Nitrogen fertilization; Ratoon cane. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832010000400016 |
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Canto,Marcos Weber do; Bona Filho,Amadeu; Moraes,Aníbal de; Hoeschl,André Ricardo; Gasparino,Eliane. |
Nitrogen (N) at 100, 200, 300, and 400 kg ha-1 was applied to Tanzania grass swards to evaluate the animal response and relationships between sward characteristics and the performance of young Nellore bulls (Bos indicus) under continuous stocking. A completely randomized experimental design was used with two replications between 11 November 2001 and 15 April 2002 when the sward heights were maintained at 60 cm by using different stocking rates. The average daily gain (ADG) (0.73 kg d-1) was not affected by N doses while the number of animal days ha-1 increased linearly from 515 to 1267. On the other hand, the linear increase in the animal yield was 399, 653, 755, and 895 kg ha-1 for N at 100, 200, 300, and 400 kg ha-1, respectively, while the ratio between... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Animal performance; Nitrogen fertilization; Panicum maximum; Tropical grass. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982009000700003 |
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Freitas,Viviane Alves; Fernandes,Martielle Batista; Mizobutsi,Edson Hiydu; Mizobutsi,Gisele Polete; Ribeiro,Regina Cássia Ferreira; Pegoraro,Rodinei Facco. |
Abstract The balanced supply of nitrogen to fruit trees leads to higher fruit quality and reduced incidence of diseases. The aim of this study was to evaluate anthracnose intensity and the physical and chemical characteristics of ‘Prata Anã’ banana under different nitrogen doses. Regarding anthracnose intensity, N doses of 150, 200, 250, 400 and 600 kg ha-1 were used. The Area Under the Incidence Progress (AUIPC) and Severity Curves (AUSPC) were evaluated. The physical and chemical characteristics were: fruit and pulp mass; soluble solids; starch; total, reducing and non-reducing sugars; coloration and nutrient concentration in peel, evaluated every three days for 15 days. Plants fertilized with N doses of 200, 250 and 400 kg.ha-1 had lower AUIPC values... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nitrogen fertilization; Colletotrichum musae; Musa spp; Postharvest pathology. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452019000500401 |
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Lopes,M.N.; Cândido,M.J.D.; Pompeu,R.C.F.F.; Silva,R.G.; Carneiro,M.S.S.; Morais Neto,L.B.; Peixoto,M.J.A.; Carvalho,T.C.F.. |
ABSTRACT To evaluate the biomass components of massai grass subjected to nitrogen (N) fertilization levels (control - 0; 400; 800 and 1200 kg ha-1 year-1 of N) and under rotational stocking with sheep, this study was undertaken using a completely randomized design with measurements repeated in time. A quadratic response was observed reaching maximum values as the levels of nitrogen fertilization increased for green forage biomass, green leaf biomass, green stem biomass (5,172.9; 4,146.3; 1,033.9 kg ha-1 cycle-1, respectively), forage total density (179.1 kg ha-1 cm-1), canopy height (36.8 cm) and live material/dead material ratio (4.0) at levels 896; 934; 797; 879.2; 751.4 and 1,161 kg ha-1 year-1 of N, respectively. For all variables, oscillation was... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Forage production; Green leaf biomass; Nitrogen fertilization; Panicum maximum. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352019000401411 |
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Lopes,Marcos Neves; Cândido,Magno José Duarte; Pompeu,Roberto Cláudio Fernandes Franco; Silva,Rodrigo Gregório da; Carvalho,Thaíse Cristine Ferreira de; Sombra,Weberte Alan; Morais Neto,Luiz Barreto de; Peixoto,Márcio José Alves. |
This study evaluated the biomass flow of massai grass in regrowth subjected to different nitrogen levels (control - no fertilization; 400; 800; and 1200 N kg ha-1year-1) and under rotational stocking with sheep, in a completely randomized design with repeated measures over time. The leaf elongation rate increased with increasing nitrogen levels (N) and the fourth grazing cycle presented a lower value compared with the others. The stem elongation rate responded linearly with increasing levels of N, but it was not influenced by grazing cycles. The senescence rate of leaves remaining before grazing and after grazing were not influenced by the nitrogen fertilization or amended with successive grazing cycles. The phyllochron was influenced only by the nitrogen... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Morphogenesis; Nitrogen fertilization; Panicum maximum × Panicum infestum. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982013000100003 |
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Alves,Aglair C; Jesus,Fábio N; Alves,Péricles B; Santos,Hamilton V; Souza,Girlene S; Santos,Anacleto R. |
ABSTRACT The aim of this study was to evaluate the effect of light quality and nitrogen availability on the biomass production, yield and composition of essential oil of lemon balm (Lippia alba). Five doses of N (0; 40; 80; 120 and 160 kg ha-1) were studied, using urea and three light quality conditions obtained with the use of colored shading nets (blue and red), 50% irradiance and under full sun. The experiment was arranged in a 5x3 factorial scheme, in split plots, with seven replicates. After 60 days of cultivation under the shading nets, a higher dry leaf biomass (4.83 g per plant) was observed in the plants under blue net cultivation at a dose of 102 kg ha-1 of N. The plants grown under full sun presented greater amount of neral and geranial, major... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Lippia alba; Shading nets; Nitrogen fertilization; Medicinal plant; Light quality. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362018000100094 |
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Müller,Tânia Maria; Sandini,Itacir Eloi; Rodrigues,João Domingos; Novakowiski,Jaqueline Huzar; Basi,Simone; Kaminski,Tatyanna Hyczy. |
Nitrogen (N) is the most limiting nutrient for corn production. Thereby, the goal of the paper was to evaluate inoculation methods of Azospirillum brasilense in order to partially supply N required by the crop. The experiment was carried out in Guarapuava, PR, Brasil, in 2011/2012 growing season. Randomized blocks with factorial 3 inoculation methods (seed treatment, planting furrow and non-inoculated control) x 5 doses of nitrogen (0, 75, 150, 225 and 300kg ha-1) x 8 replications was used as the experimental design. Leaf are index, foliar nitrogen content, total chlorophyll, grains per ear and yield were evaluated. There was significant interaction between inoculation methods and nitrogen fertilization to leaf area index, but not for yield. Inoculation... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nitrogen fertilization; Diazotrophic bacteria; Seed treatment; Planting furrow. |
Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016000200210 |
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SCHONINGER,EVANDRO L.; VILLALBA,HUGO A. GONZÁLEZ; BENDASSOLLI,JOSÉ ALBERTINO; TRIVELIN,PAULO CESAR O.. |
Abstract Best fertilizer management practices such as adopting the right N sidedress timing can reduce N losses by volatilization, thus, raising N-fertilizer recovery and grain yield. To evaluate ammonia (N-NH3 ) losses, N-fertilizer recovery and grain yield as a function of urea sidedress timing in corn, a field study was conducted during the 2011-2012 and 2012-2013 growing seasons, adopting a complete randomized block design with four replications. Treatments consisted of urea sidedress timing (140 kg N ha-1) at V4, V6, V8, V10, and V12 growth stages, plus a control without sidedress N. The largest N losses by N-NH3 volatilization occurred when urea was applied at V10 or V12 growth stages, reaching losses of 35 and 41 % of the total applied N. Although... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: 15N isotope; Nitrogen fertilization; Nitrogen volatilization; Zea mays. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652018000703299 |
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Pontes,Laíse da Silveira; Tullio,Guilherme Francisco; Martins,Adriana de Souza; Moletta,José Luiz; Porfírio-da-Silva,Vanderley. |
Abstract In this study, the objective was to assess the influence of two doses of N (90 and 180 kg N ha-1, added to the winter pastures), two integrated crop-livestock systems (ICLS, with and without trees) and five positions between the tree rows, on the corn (Zea mays L.) quality and productivity, for silage and grain. Adopting the complete randomized block design, the treatments included three replicates. In 2006, following the 14 x 3 m spacing (currently with 158 trees ha-1) the trees were planted in 6 out of the 12 paddocks. While the corn was implemented during summer of 2013/2014, cattle grazing on the annual pasture was done during the prior winter, in both ICLS. Corn for silage was reaped at the R5 phenological stage, whereas for grains it was... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Agroforestry; Eucalyptus dunnii; Grevillea robusta; Nitrogen fertilization; Silage quality. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902018000200315 |
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Maia,Suelen Cristina Mendonça; Soratto,Rogério Peres; Liebe,Suzane Maria; Almeida,Adriana Queiroz de. |
Abstract: The objective of this work was to establish the diagnostic leaf and the nitrogen sufficiency index (NSI) values most appropriate to estimate N requirement by the 'Pérola' common bean (Phaseolus vulgaris), based on chlorophyll meter monitoring. The diagnostic leaf was defined in an experiment with five N rates, and up to four sampling dates of the diagnostic leaves were evaluated (first, second, and third completely expanded leaves from the apex). The NSI was established in two crop seasons, under six N managements: M1, 40 kg ha-1 N at sowing + 80 kg ha-1 10 days after emergence (DAE) + 80 kg ha-1 20 DAE (reference rate); M2, 20 kg ha-1 at sowing + 40 kg ha-1 10 DAE + 40 kg ha-1 20 DAE (recommended rate); M3, 20 kg ha-1 at sowing + 30 kg ha-1 when... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Phaseolus vulgaris; Diagnostic leaf; Nitrogen fertilization; Nitrogen sufficiency index; Nitrogen use efficiency; Relative chlorophyll index. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2017000700512 |
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Santana,Augusto C. de A.; Oliveira,Emídio C. A. de; Silva,Vinícius S. G. da; Santos,Renato L. dos; Silva,Magda A. da; Freire,Fernando J.. |
ABSTRACT Nitrogen is the most limiting nutrient for the development of sugarcane and particularly the use of more productive and demanding varieties, for which the doses of nitrogen fertilization necessary during the plant cane cycle may be underestimated and the critical levels of nitrogen in the leaf may be modified. The objective of this study was to determine the critical nitrogen dilution curve (CNDC) for leaves, evaluate the aboveground dry mass production (DM) and productivity of two varieties fertilized with N in the plant cane cycle. The study was conducted under field conditions, evaluating two sugarcane varieties RB92579 and RB867515, fertilized with seven doses of N (0, 30, 60, 90, 120, 150 and 200 kg ha-1). The varieties and doses were... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Saccharum spp.; Nitrogen fertilization; Aboveground dry matter; Variety. |
Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662020000400244 |
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Vieira, Maria do Carmo; UFGD; Zárate, Néstor Antonio Heredia; UFGD; Sanches, Maria Aparecida dos Santos; UFGD; Bendasso, Michelli Cristine Nunes Facholi; UFGD. |
O trabalho teve por objetivo avaliar a produção e as características morfológicas dos capítulos florais da camomila ‘Mandirituba’ em função do uso de doses de nitrogênio (3, 18, 30, 42 e 57 kg ha-1), na forma de sulfato de amônio, e de cama-de-frango semidecomposta (1.000, 6.000, 10.000, 14.000 e 19.000 kg ha-1). Os tratamentos foram determinados utilizando-se a matriz experimental Plan Puebla III, resultando nas combinações de N e de cama-de-frango, respectivamente: 18/6.000, 42/6.000, 18/14.000, 42/14.000, 30/10.000, 3/6.000, 57/14.000, 18/1.000 e 42/19.000 kg ha-1. O delineamento experimental utilizado foi de blocos casualizados, com nove tratamentos e quatro repetições. Avaliou-se a altura de plantas e, nos capítulos florais, foram avaliados número,... |
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Palavras-chave: 5.01.03.04-0 Produção de Mudas Chamomilla recutita (L.) Rauschert; Resíduo orgânico; Adubação nitrogenada. Chamomilla recutita (L.) Rauschert; Organic residue; Nitrogen fertilization. |
Ano: 2009 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/6632 |
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Aguilar, Poliana Batista de; Teixeira, Fábio Andrade; Silva, Fabiano Ferreira da; Pires, Aureliano José Vieira; Nascimento, Paulo Valter Nunes; Santos, Otanael Oliveira dos. |
The objective of this study was to evaluate the effect of different levels of nitrogen on deferred pastures of Urochloa brizantha cv. Marandu, and the implications on the economic viability of production of Nellore heifers. This was a completely randomized design with four treatments (T1 = deferred pasture without nitrogen fertilization; T2 = deferred pasture fertilized with 50 kg N ha-1, T3 = deferred pasture with 100 kg N ha-1, T4 = deferred pasture with 150 kg N ha-1) and four replications (16 fertilized paddocks). First, there were used 48 Nellore heifers, average eight months of age and initial body weight of 178.69 ± 26.67 kg, with three heifers in each paddock, in all treatments, in a continuous grazing system, with variable stocking rate. Only the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Economic analysis; Deferment; Nitrogen fertilization; Profitability; Urea. |
Ano: 2016 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAnimSci/article/view/28375 |
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Stocker,Vinícius; Souza,Eduardo G. de; Johann,Jerry A.; Beneduzzi,Humberto M.; Silva,Franciléia de O. e. |
ABSTRACT The application of nitrogen (N) fertilizer is complex and expensive, so its correct management has financial and environmental benefits. The use of optical proximity sensors is a promising technique. However, the movement of the agricultural machinery or of the person carrying the sensor will result in height differences and/or different tilt and twist angles with respect to the canopy. We considered whether these variations would affect the reflectance measurement. In this study, we took normalized difference vegetation index (NDVI) readings of a wheat canopy, to which 90 kg ha-1 of urea had been applied in stage 5, and observed the NDVI in stages 6, 8 and 10.5. We also tested soybeans, to which 90 kg ha-1 of urea had been applied in stage R1,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nitrogen fertilization; Precision agriculture; GreenSeeker; NDVI. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000800096 |
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Registros recuperados: 67 | |
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