Currently, the information available concerning requirements for optimum crop growth and development, dry matter production, and nutrient uptake and partitioning for Cantaloupes and New Mexico chile type cultivars is limited. Such information is required to predict and identify critical stages of growth in order to develop efficient nutrient management programs for these crops. The goals of this dissertation are: 1) to obtain general irrigated cantaloupe and New Mexico chile plants development models as a function of heat units accumulated after planting (HUAP), and 2) to determine dry matter production and nutrient uptake and partitioning patterns of these crops as a function of HUAP. Four primary investigations are presented in this dissertation. In the first and second studies, plant development models for irrigated cantaloupe and New Mexico chile-type cultivars were obtained. For cantaloupe plants, early bloom occurred at 265 ± 47 HUAP, early fruit set at 381 ± 51 HUAP, early netting at 499 ± 63 HUAP, and physiological maturity at 746 ± 66 HUAP. For chile plants, first bloom occurred at 530 ± 141 HUAP, early bloom at 750 ± 170 HUAP, peak bloom at 1006 ± 145 HUAP, first green chile harvest at 1329 ± 120 HUAP, and red harvest stage at 1798 ± 58 HUAP. Also, these studies revealed that beyond the early netting stage (approximately 499 HUAP), cantaloupe fruits were the strongest sinks for dry matter accumulation. For chile plants, between the first green chile harvest and red chile harvest stages (approximately at 1550 HUAP), chile pods developed into stronger sinks for dry matter accumulation. The third and fourth investigations revealed that the period of maximum nutrient uptake coincides with that of maximum dry matter accumulation for both crops. The overall total nutrient uptake of N, P, K, Ca, Mg, S, B, Zn, Mn, Fe, and Cu for cantaloupe plants was 138, 21, 213, 132, 29, 28, 0.17, 0.20, 0.13, 2.0, and 0.06 kg ha⁻¹, for chile plants, the overall total nutrient was 216, 20, 292, 117, 56, 28, 0.31, 0.20, 0.31, 1.6 and 0.14 kg ha⁻¹ for these nutrients respectively.

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Resumo: O experimento foi conduzido na UNESP - Campus de Botucatu, Faculdade de Medicina Veterinária e Zootecnia. O delineamento experimental foi em blocos ao acaso num arranjo fatorial com três cultivares de Brachiaria brizantha (Marandu, Xaraés e BRS Piatã) e duas alturas de resíduo (15 e 25 cm), no total de seis tratamentos com quatro repetições (parcelas de 20 m2). O período de avaliação foi de um ano (01/12/2007 a 10/12/2008), com a realização de oito cortes, sendo três na primavera, três no verão, um no outono e um no inverno. A produção de massa seca (MS) da Xaraés foi maior no verão e na primavera em relação à Marandu. No somatório do ano a produtividade de MS da Xaraés foi 27,07% superior à Marandu, alcançando valor elevado (20.023 kg/ha), o que demonstra o potencial de utilização deste genótipo, principalmente em sistemas de produção de bovinos de corte mais intensivos. A produção de MS da Piatã nas estações do ano foi semelhante à Marandu, totalizando 17.572 e 15.757 kg/ha, respectivamente. Os dados de produção indicam que a Piatã apresentou a melhor distribuição da forragem produzida ao longo do ano. A produção de forragem das cultivares foi maior na altura do resíduo de 15 cm no verão e inverno, e não diferiu nas alturas de manejo no outono e primavera, demonstrando exigências diferentes de manejo do capim ao longo do ano. Os resultados obtidos confirmam a recomendação e a importância da cultivar Piatã como alternativa de utilização e diversificação das pastagens nos sistemas produtivos. / Abstract: The experiment was conducted in the School of Veterinary Medicine and Animal Science of UNESP - Botucatu Campus. The experimental design was a complete randomized blocks in a factorial arrangement with three cultivars of Brachiaria brizantha (Marandu, Xaraés and BRS Piatã) and two stubble heights (15 and 25 cm), in the total six treatments with four replications (20 m² plots). The evaluation period was of one year (12/01/2007 to 12/10/2008) with eight cuts: three in the spring, three in the summer, one in the fall and one in the winter. The production of dry matter (DM) of Xaraés in summer and spring were higher than Marandu with a total of 27.07% higher DM than Marandu. The total DM production was 20,023 kg/ha, demonstrating the potential of use of the Xaraés cultivar, especially in more intensive systems of beef cattle production. DM production of Piatã in the seasons was similar to Marandu, totalizing 17,572 and 15,757 kg/ha, respectively. The production data indicate that Piatã cultivar had the best distribution of forage produced during the year. The forage production of cultivars was higher in the stubble height of 15 cm in summer and winter, and did not differ for two heights of management in the fall and spring, showing different requirements of grass management during the year. The results confirm the recommendation and the importance of Piatã cultivar as an alternative of use and diversification of pastures in the production systems. / Orientador: Ciniro Costa / Coorientador: Paulo Roberto de Lima Meirelles / Banca: Heraldo César Gonçalves / Banca: Roberto Antonio Rodella / Banca: Cacilda Borges do Valle / Banca: Valdo Rodrigues Hering / Doutor

Orientador: Carmen Sílvia Fernandes Boaro / Banca: João Domingos Rodrigues / Banca: Conceição Aparecida Cossa / Resumo: A Lippia alba (Mill.) N.E.Br. ex Britt & Wilson é uma importante espécie medicinal de uso popular conhecida como erva cidreira brasileira. Trata-se de um arbusto, cujas folhas frescas ou secas e inflorescências são utilizadas na forma de chás, macerados, compressas, pomadas, banhos e extratos alcoólicos. Suas folhas apresentam ação antiespasmódica, moluscicida, fungicida, calmante e digestiva. Considerando, a) a inexistência de estudos sobre a L. alba em hidroponia b) a utilização de solução nutritiva para atender as necessidades da espécie, fornecendo nutrientes de maneira balanceada e possibilitando a produção de plantas com adequada qualidade e em menor espaço de tempo, c) a necessidade de produção de matéria prima para uso medicinal popular e farmacêutico, o presente estudo objetivou avaliar o desenvolvimento e as trocas gasosas de L. alba submetida à variação das concentrações dos nutrientes a partir da diluição da solução nutritiva de Hoagland e Arnon (1950). Assim, as plantas foram cultivadas em quatro tratamentos, constituídos pela variação de nutrientes na solução nutritiva n°2 de Hoagland e Arnon (1950), ou seja, em solução completa (100%) e diluída à 80%, 60% e 40% em relação à completa. As variáveis avaliadas foram área foliar, massas secas dos diferentes órgãos, razão de área foliar (RAF), área foliar específica (AFE), razão de massa foliar (RMF), taxa de crescimento absoluto (TCA), taxa assimilatória líquida (TAL), taxa de crescimento relativo (TCR), taxa de assimilação de CO2 (A, mmolCO2 m-2 s-1), condutância estomática (gs, mol m-2s-1), transpiração (E, mmol H2O m-2 s-1), concentração intercelular de CO2 na folha (Ci, mmolCO2 mol-1ar) e eficiência de uso da água (EUA). Os resultados obtidos permitem concluir que: 1. As concentrações dos nutrientes na solução nutritiva, de maneira geral, foram excessivas para... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Lippia alba (Mill.) N.E.Br. ex Britt & Wilson is a native species popular known as "erva-cidreira brasileira". It is a shrub who's fresh or dried leaves and flowers are used as teas, macerated, bandages, ointments, baths and alcoholic extracts. Its leaves have an antispasmodic, molluscicidal, fungicidal, sedative and digestive. Considering a) the lack of studies about L. alba in hydroponic cultivation b) the use of nutrient solution to meet the needs of the species, providing nutrients in a balanced manner and enabling the production of plants with adequate quality and in shortest time, c) the need for production of raw materials for folk medical and pharmacist, the present study evaluate the development and gas exchange of L. alba subjected to varying concentrations of nutrients from the dilution of Hoagland and Arnon (1950). Thus, plants were grown in four treatments, consisting by variation of nutrients in the nutrient solution No 2 of Hoagland and Arnon (1950), full solution (100%), diluted to 80%, 60% and 40% compared to the full. Variables evaluated were leaf area, dry masses of different organs, leaf area ratio (LAR), specific leaf area (SLA), leaf mass ratio (LMR), absolute growth rate (AGR), net assimilation rate (NAR), rate relative growth (RGR), rate of CO2 assimilation (A, molCO2 m m-2 s-1), stomatal conductance (gs, mol m-2s-1), transpiration (E, mmol H2O m-2 s -1), intercellular CO2 concentration in the leaf (Ci, molCO2 m mol-1AR) and efficiency of water use (USA). The results showed that: 1. The concentrations of nutrients in the nutrient solution, in general, were excessive for the development and gas exchange of Lippia alba, 2. The cultivation of the species with a dilute solution of 80% resulted in higher total dry matter in the shortest time possible, which, however, was highest among the various treatments, 3. Diluted solutions at 60 and 40% ...(Complete abstract click electronic access below) / Mestre

Made available in DSpace on 2014-06-11T19:26:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-21Bitstream added on 2014-06-13T18:54:56Z : No. of bitstreams: 1 janani_jk_me_botfca.pdf: 939751 bytes, checksum: 44d9b0cf69e527a9491a6a09a3dc8d50 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A Lippia alba (Mill.) N.E.Br. ex Britt & Wilson é uma importante espécie medicinal de uso popular conhecida como erva cidreira brasileira. Trata-se de um arbusto, cujas folhas frescas ou secas e inflorescências são utilizadas na forma de chás, macerados, compressas, pomadas, banhos e extratos alcoólicos. Suas folhas apresentam ação antiespasmódica, moluscicida, fungicida, calmante e digestiva. Considerando, a) a inexistência de estudos sobre a L. alba em hidroponia b) a utilização de solução nutritiva para atender as necessidades da espécie, fornecendo nutrientes de maneira balanceada e possibilitando a produção de plantas com adequada qualidade e em menor espaço de tempo, c) a necessidade de produção de matéria prima para uso medicinal popular e farmacêutico, o presente estudo objetivou avaliar o desenvolvimento e as trocas gasosas de L. alba submetida à variação das concentrações dos nutrientes a partir da diluição da solução nutritiva de Hoagland e Arnon (1950). Assim, as plantas foram cultivadas em quatro tratamentos, constituídos pela variação de nutrientes na solução nutritiva n°2 de Hoagland e Arnon (1950), ou seja, em solução completa (100%) e diluída à 80%, 60% e 40% em relação à completa. As variáveis avaliadas foram área foliar, massas secas dos diferentes órgãos, razão de área foliar (RAF), área foliar específica (AFE), razão de massa foliar (RMF), taxa de crescimento absoluto (TCA), taxa assimilatória líquida (TAL), taxa de crescimento relativo (TCR), taxa de assimilação de CO2 (A, mmolCO2 m-2 s-1), condutância estomática (gs, mol m-2s-1), transpiração (E, mmol H2O m-2 s-1), concentração intercelular de CO2 na folha (Ci, mmolCO2 mol-1ar) e eficiência de uso da água (EUA). Os resultados obtidos permitem concluir que: 1. As concentrações dos nutrientes na solução nutritiva, de maneira geral, foram excessivas para... / Lippia alba (Mill.) N.E.Br. ex Britt & Wilson is a native species popular known as “erva-cidreira brasileira”. It is a shrub who’s fresh or dried leaves and flowers are used as teas, macerated, bandages, ointments, baths and alcoholic extracts. Its leaves have an antispasmodic, molluscicidal, fungicidal, sedative and digestive. Considering a) the lack of studies about L. alba in hydroponic cultivation b) the use of nutrient solution to meet the needs of the species, providing nutrients in a balanced manner and enabling the production of plants with adequate quality and in shortest time, c) the need for production of raw materials for folk medical and pharmacist, the present study evaluate the development and gas exchange of L. alba subjected to varying concentrations of nutrients from the dilution of Hoagland and Arnon (1950). Thus, plants were grown in four treatments, consisting by variation of nutrients in the nutrient solution No 2 of Hoagland and Arnon (1950), full solution (100%), diluted to 80%, 60% and 40% compared to the full. Variables evaluated were leaf area, dry masses of different organs, leaf area ratio (LAR), specific leaf area (SLA), leaf mass ratio (LMR), absolute growth rate (AGR), net assimilation rate (NAR), rate relative growth (RGR), rate of CO2 assimilation (A, molCO2 m m-2 s-1), stomatal conductance (gs, mol m-2s-1), transpiration (E, mmol H2O m-2 s -1), intercellular CO2 concentration in the leaf (Ci, molCO2 m mol-1AR) and efficiency of water use (USA). The results showed that: 1. The concentrations of nutrients in the nutrient solution, in general, were excessive for the development and gas exchange of Lippia alba, 2. The cultivation of the species with a dilute solution of 80% resulted in higher total dry matter in the shortest time possible, which, however, was highest among the various treatments, 3. Diluted solutions at 60 and 40% ...(Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:32:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-03-26Bitstream added on 2014-06-13T21:05:28Z : No. of bitstreams: 1 lupatini_gc_dr_botfmvz.pdf: 341308 bytes, checksum: df486ae1605629080494d4b067f0a6e2 (MD5) / Universidade Estadual Paulista (UNESP) / O experimento foi conduzido na UNESP – Campus de Botucatu, Faculdade de Medicina Veterinária e Zootecnia. O delineamento experimental foi em blocos ao acaso num arranjo fatorial com três cultivares de Brachiaria brizantha (Marandu, Xaraés e BRS Piatã) e duas alturas de resíduo (15 e 25 cm), no total de seis tratamentos com quatro repetições (parcelas de 20 m2). O período de avaliação foi de um ano (01/12/2007 a 10/12/2008), com a realização de oito cortes, sendo três na primavera, três no verão, um no outono e um no inverno. A produção de massa seca (MS) da Xaraés foi maior no verão e na primavera em relação à Marandu. No somatório do ano a produtividade de MS da Xaraés foi 27,07% superior à Marandu, alcançando valor elevado (20.023 kg/ha), o que demonstra o potencial de utilização deste genótipo, principalmente em sistemas de produção de bovinos de corte mais intensivos. A produção de MS da Piatã nas estações do ano foi semelhante à Marandu, totalizando 17.572 e 15.757 kg/ha, respectivamente. Os dados de produção indicam que a Piatã apresentou a melhor distribuição da forragem produzida ao longo do ano. A produção de forragem das cultivares foi maior na altura do resíduo de 15 cm no verão e inverno, e não diferiu nas alturas de manejo no outono e primavera, demonstrando exigências diferentes de manejo do capim ao longo do ano. Os resultados obtidos confirmam a recomendação e a importância da cultivar Piatã como alternativa de utilização e diversificação das pastagens nos sistemas produtivos. / The experiment was conducted in the School of Veterinary Medicine and Animal Science of UNESP - Botucatu Campus. The experimental design was a complete randomized blocks in a factorial arrangement with three cultivars of Brachiaria brizantha (Marandu, Xaraés and BRS Piatã) and two stubble heights (15 and 25 cm), in the total six treatments with four replications (20 m² plots). The evaluation period was of one year (12/01/2007 to 12/10/2008) with eight cuts: three in the spring, three in the summer, one in the fall and one in the winter. The production of dry matter (DM) of Xaraés in summer and spring were higher than Marandu with a total of 27.07% higher DM than Marandu. The total DM production was 20,023 kg/ha, demonstrating the potential of use of the Xaraés cultivar, especially in more intensive systems of beef cattle production. DM production of Piatã in the seasons was similar to Marandu, totalizing 17,572 and 15,757 kg/ha, respectively. The production data indicate that Piatã cultivar had the best distribution of forage produced during the year. The forage production of cultivars was higher in the stubble height of 15 cm in summer and winter, and did not differ for two heights of management in the fall and spring, showing different requirements of grass management during the year. The results confirm the recommendation and the importance of Piatã cultivar as an alternative of use and diversification of pastures in the production systems.

Thesis (MSc. (Pasture Science)) -- University of Limpopo, 2016 / South Africa is regarded as a semi-arid area; only 28% of the country receives more than 600 mm rainfall recorded annually. Sustainable utilization of cool season fodder grasses in summer rainfall areas to produce winter animal feed remains a major problem. Farmers are affected by a shortage of adequate, good quality herbage for livestock during winter and dry periods on commercial farms. The study aimed to evaluate and compare the production potential of six Festulolium hybrids, three Dactylis species, and five Lolium hybrids and three grass-legume mixtures in the summer rainfall area. A total of 17 cultivars were evaluated for their DM production under the treatment of different fertilizer levels on three planting dates (16 March 2011, 21 April 2011 and 4 April 2012). The study was carried out at Hygrotech Seed Company (Experimental site), Dewagensdrift in Moloto Village outside Pretoria in the Gauteng Province. Data was collected on a monthly basis from sub-plots of 1 m x 1 m (m2) in 51 plots of 1.5 m x 6 m (9 m2), with nine rows that were 10 cm apart arranged under RCBD with three replicates per cultivar. Harvested fresh samples were taken, weighed, dried at 60ºC until they reached a constant dry weight and weighed to determine DM content. A Fischer’s protected LSD at the 5 % level was performed to compare the treatment means. Over a period of three years of study, it shows that the low fertilizer level resulted in the lowest DM production, with no significant difference occurring between medium and high fertilizer levels. To achieve optimum DM production with minimum cost medium fertilizer is recommended. The cultivars responded differently to the three different planting dates. The time of planting had an effect on DM production in winter. It is recommended that Festulolium hybrids and Lolium hybrids be planted earlier (March) for better DM production in winter. / National Research Foundation (NRF)

Prairie bromegrass is a cool-season perennial bunchgrass with potential as a valuable forage crop in the southeastern USA. The objective of this study was to compare dry matter production, persistence, nutritive value, and beef cattle grazing preference of two experimental lines and a commercial species (cv. Matua) of prairie bromegrass. Plots were established in a randomized complete block design with four replications. When each plot accumulated at least 20 cm of growth, plots were grazed with Hereford x Angus steers at a stocking rate of 8400 kg/ha until the first plot was grazed down to 7 cm in height. Pre- and post-grazing quadrats were taken for DM and animal preference estimation and nutrient analyses. No differences in nutritive value or grazing preference were seen among species. Treatment interactions were observed for DM production and persistence. The results suggest that there are differences in growth traits among the bromegrass species observed.

Thesis (MSc. (Agriculture Pasture Science)) -- University of Limpopo, 2018 / This study was conducted at the University of Limpopo’s Experimental Farm (Syferkuil), in the Limpopo Province, South Africa. The objective was to determine the effect of foliar fertilizers on the dry matter production over a period of two growing seasons. The experiment was laid out in a 3 x 3 factorial arrangement, fitted in a randomized complete block design (RCBD), with 4 replications. The experiment was planted on 28th March 2014 for season 1 (2014) and 31st March 2015 for season 2 (2015). Three sources of fertilizer (Nitrospray Plus, Potaspray and a combination of the two) were applied to stooling rye at three different fertilizer application rates (0 kg or ℓ/ha, 2.5 kg or ℓ/ha and 5.0 kg or ℓ/ha). The Nitrospray Plus and Potaspray fertilizers were applied on the 09th May, 02nd July, 27th August and 30th October 2014 for Season 1 (2014). During the Season 2 (2015), they were applied on 11th May, 04th July, 29th August and 02nd November 2015. The application was done using a knapsack sprayer. Above-ground biomass was harvested four times during each season when the plants reached a height of 25–30 cm. During 2014, harvesting was done on the 27th May, 24th July, 12th September and the 17th November 2014. During 2015, harvesting was done on the 29th May, 26th July, 14th September and the 19th November 2015. The dry matter production was determined by harvesting 1 m2 quadrates at 3 cm height. After weighing fresh material, it was oven–dried at 55oC until a constant mass was reached. Samples were then weighed again and the DM production (kg/ha) was calculated. Results were compared, using analysis of variance and the Fisher’s LSD test at P≤ 0.05 within each season. Based on the Least Significance Difference test, treatments were grouped in different production classes. During both seasons, fertilizer application rates had a significant (P≤0.001) influence on dry matter production. In 2014, the highest total dry matter production obtained was 5323 kg/ha in the high potassium fertilizer treatment and the lowest total dry matter was 4049 kg/ha in the control or zero application treatment. xiii In 2015, the highest total dry matter production obtained was 5595 kg/ha in the high potassium fertilizer treatment and the lowest 3678 kg/ha in the control treatment. Potassium fertilizers produced significantly (P≤0.001) higher than nitrogen fertilizers in both seasons. The main conclusions from this study were that high foliar fertilizer application rates (5.0 kg/ha) led to high, low foliar application rates (2.5 kg/ha) to lower and no fertilizer to low dry matter production. High levels of potassium produced the best, followed by combinations of intermediate potassium and nitrogen, and high nitrogen application rates. Yields of above 5000 kg/ha were obtained under high potassium rates. Lower rates led to total productions of more than 4000 kg/ha, while no foliar application produced between 3700 and 4000 kg/ha. It was also concluded that stooling rye is a suitable winter fodder crop for the Pietersburg Plateau Bushveld, but that the application of fertilizers is necessary for increased dry matter production. Both and Nitrospray and Potaspray Plus, as individual foliar fertilizers or in combination, can be applied to increase the dry matter production of stooling rye. However, it is essential to investigate the adaptability of stooling rye in other areas of the Limpopo bushveld, to determine its suitability as a fodder crop in other areas in the province. Keywords: Dry matter production, cutting dates, foliar fertilizers, Nitrospray Plus, Potaspray.

Made available in DSpace on 2014-06-11T19:30:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-09-21Bitstream added on 2014-06-13T19:40:03Z : No. of bitstreams: 1 borghi_e_dr_botfca.pdf: 848383 bytes, checksum: 44d5e9fbafc7f7b8fefd5bb90ee2d35a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O trabalho de pesquisa teve por objetivo: 1) avaliar a produtividade de grãos da cultura de milho em épocas de consorciação com Brachiaria brizantha cv. Marandu e Panicum maximum cv. Mombaça em SPD; 2) avaliar o desempenho das plantas forrageiras consorciadas em épocas e a resposta à adubação nitrogenada aplicada após a colheita do milho, quanto à produtividade e valor nutritivo; 3) verificar, na B. brizantha, o acúmulo de nitrogênio total e proveniente do fertilizante nitrato de amônio (NPPF) com doses de nitrato de amônio (15NH4NO3) aplicado em cobertura nas plantas forrageiras após a colheita da cultura do milho; 4) avaliar o residual da adubação nitrogenada nas plantas forrageiras na cultura do milho cultivado em sucessão; 5)avaliar o aproveitamento do nitrogênio (15N), aplicado em cobertura na B. brizantha, pela cultura sucedânea do milho. Para atingir tais propósitos, foram conduzidos três estudos simultaneamente, conduzidos em condições de campo durante os anos agrícolas de 2003/04, 2004/05 e 2005/06 na Fazenda Experimental Lageado, da Faculdade de Ciências Agronômicas – Campus de Botucatu, em NITOSSOLO VERMELHO Estruturado, cultivado em SPD. O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetições. No estudo I, os tratamentos foram: 1) cultivo do milho solteiro; 2) milho com Brachiaria brizantha cv. Marandu consorciada na semeadura; 3) milho com Brachiaria brizantha cv. Marandu consorciada na adubação de cobertura; 4) milho com Panicum maximum cv. Mombaça consorciado na semeadura; 5) milho com Panicum maximum cv. Mombaça consorciado na adubação de cobertura. No segundo e terceiro anos de condução do experimento (anos agrícolas 2004/05 e 2005/06), após a colheita da cultura do milho, foi aplicado nitrato de amônio em cobertura nas quantidades equivalentes a 0, 30, 60 e 120 kg ha-1 de N... / The present work aimed to: 1) evaluate corn grain yield under different intercropping epochs with Brachiaria brizantha cv. Marandu and Panicum maximum cv. Mombaça under no-tillage system; 2) evaluate the performance of the forages intercropped and the answer of these crops to nitrogen rates applied after corn harvest, considering the productivity and nutritional value; 3) verify, in B. brizantha, the total nitrogen accumulation and the nitrogen accumulated from the fertilizer ammonium nitrate (NPPF) under different ammonium nitrate rates (15NH4NO3) applied in the forages as cover crop after corn harvest; 4) evaluate the nitrogen profit (15N), applied as cover crop in B. brizantha, by corn cultivated in succession. To reach the proposed objectives, it was carried on three simultaneous studies, carriers on at field conditions, during the cropping years of 2003/04, 2004/05 and 2005/06 at Lageado Experimental Farm, College of Agricultural Sciences, in Botucatu, State of São Paulo, Brazil, in a structured Oxisol cultivated under no-tillage system. The experimental design was in blocks completely randomized, with four replicates. In the experiment I, the treatments were: 1) corn cultivated alone; 2) corn with Brachiaria brizantha cv. Marandu as consortium seeded at corn seeding; 3) corn with B. brizantha cv. Marandu as consortium seeded at corn cover fertilization; 4) corn with Panicum maximum cv. Mombaça as consortium seeded at corn seeding; 5) corn with P. maximum cv. Mombaça as consortium seeded at corn cover fertilization. In the second and third experimental years (2004/05 and 2005/06), after corn grain harvest, it was applied cover rates of ammonium nitrate, equivalent to 0, 30, 60 and 120 kg ha-1 of N. Only under B. brizantha were allocated micro parcels in which it was applied enriched ammonium nitrate (15NH4NO3), to evaluate the N recovery by Brachiaria ...(Complete abstract click electronic access below)