Forage performance and cattle production as a function of the seasonality of a Brazilian tropical region

This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3x3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry,and end of dry season), with repeated measuresover time. The following variables were evaluated: canopyheight, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitrodry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore),was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction amongcultivarsand period of the year the similarity in animal performance amongthe cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.(AU)

Forage performance and cattle production as a function of the seasonality of a Brazilian tropical region

This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3 x 3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry, and end of dry season), with repeated measures over time. The following variables were evaluated: canopy height, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitro dry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore), was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction among cultivars and period of the year the similarity in animal performance among the cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.(AU)

Forage performance and cattle production as a function of the seasonality of a Brazilian tropical region / Forage performance and cattle production as a function of the seasonality of a Brazilian tropical region

This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3 x 3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry, and end of dry season), with repeated measures over time. The following variables were evaluated: canopy height, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitro dry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore), was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction among cultivars and period of the year the similarity in animal performance among the cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.

This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3 x 3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry, and end of dry season), with repeated measures over time. The following variables were evaluated: canopy height, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitro dry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore), was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction among cultivars and period of the year the similarity in animal performance among the cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.

Characteristics and classification of the quality and productive standards of the mombaça grass under a livestock-forest system or full sun / Comportamento e classificação dos padrões qualitativos e produtivos do capim mombaça em sistema sivipastoril e pleno sol

The objective of this study is to identify qualitative and productive changes in Mombasa grass under a livestock-forest system or full sun and to classify the variables that are most relevant for evaluating the qualitative performance of these systems. The experiments were conducted in shade areas, with four replications for each of the 12 treatments, including four growth cycles and three levels of shading in Mombasa grass, totaling 48 experimental units. Calcium (Ca), magnesium (Mg), potassium (K), phosphorus (P), nitrogen (N) and dry mass production (DMP) (kg ha-1) were used as discriminatory variables for the shading groups. The levels of nutrients and shading in Mombaça grass were classified using Fisher multivariate discriminant analysis (FMDA). The FDMA indicated that Mg, K, P, N, and DMP formed a discriminant function. However, DMP was the least important variable for identifying the groups. Five groups were pre-defined before FDMA: MFS 2 (Mombasa grass in full sun in the second cycle), MFS 6 (Mombasa grass in full sun in the sixth cycle), MFS 7 (Mombasa grass in full sun in the seventh cycle), M25 4 (Mombasa grass at 25% shading in the fourth cycle), and M25 7 (Mombasa grass at 25% shading in the seventh cycle). The results indicate that Mg, P, K, and N are helpful for identifying new genotypes of plants grown on shading conditions because of the responsiveness and stability of these elements to environmental changes.(AU)

Objetivou com este estudo identificar as alterações qualitativas e produtivas do capim Mombaça em sistema silvipastoril e pleno sol, e classificar as variáveis mais estratégicas para avaliação do seu desempenho qualitativo. O ensaio foi alocado em faixas de sombreamento, com quatro repetições para cada um dos 12 tratamentos - quatro ciclos e três porcentagens de sombreamento, em capim Mombaça, totalizando 48 unidades experimentais. Foram usados os macroelementos: cálcio (Ca), magnésio (Mg), potássio (K), fósforo (P) e nitrogênio (N) e Produção de massa seca (PMS) (kg ha-1) como variáveis de discriminação de grupos de sombreamento. A classificação das variáveis e dos níveis de sombreamento enriquecido com mombaça, procedeu-se por meio da Análise Multivariada Discriminante de Fisher (ADF). Foi possível com o auxílio da ADF identificar as variáveis Mg, K, P, N e PMS como significativas para formação da função discriminante. Entretanto, o teor de PMS foi o menos relevante para identificação dos grupos. Cinco grupos foram pré-definidos antes da análise discriminante, MSP 2º (Mombaça pleno sol 2º ciclo), MSP 6º(Mombaça pleno sol 6º ciclo), MSP 7º (Mombaça pleno sol 7º ciclo), M25 4º (Mombaça 25% 4º ciclo) e M25 7º (Mombaça 25% 7º ciclo). Para auxiliar na busca de novos genótipos considerando a concentração de nutrientes em estudos sobre condições de sombreamento, os elementos Mg, P, K e N oferecem grande auxílio pela sua responsividade e estabilidade as oscilações ambientais.(AU)

Variabilidade espacial das respostas produtivas e morfológicas do capim-Marandu em função dos atributos químicos e topográficos / Spatial variability of yield response and morphological Marandu grass depending on the chemical and topographical

This work aimed to evaluate the spatial variability of structural and productive responses of Marandu grass depending on the chemical characteristics of the soil and topography. The experiment was conducted in a topossequence, school of Veterinary Medicine and Animal Science, The V variables were evaluated CTC, SB, m, pH at a depth of 0-20 cm, effective depth, number of tillers (m2), production dry matter (kg ha-1), when sward (cm). 72 samples were collected in georeferenced points on sloping ground. The soil was classified as Entisol in the upper portion (top), Udorthent Eutrophic the upper third of the slope (shoulder), Udorthent eutrophic in the middle third of the slope (halfslope) and Quartzips amment Hydromorphic in the lower third (pedimento). All variables presented spatial dependence with variograms of well-defined structure. The pasture presented heterogeneity in the morphology of the canopy due to the spatial distribution of soil fertility, resulting in canopy and producing higher dry matter at the top and reaching the lower production on the shoulder of topossequence. The sward has heterogeneity in morphology depending on the spatial distribution of soil fertility and the effective depth, resulting in the creation of two management areas: 1topo and pediment, and 2 shoulder and half hillside.(AU)

Objetivou-se com este trabalho avaliar a variabilidade espacial das respostas produtivas e estruturais do capim Marandu em função das características químicas do solo e da topografia do terreno. O experimento foi conduzido em uma topossequência, na escola de Medicina Veterinária e Zootecnia. Foram avaliadas as variáveis V, CTC, SB, m, pH, na profundidade de 0-20cm, profundidade efetiva, número de perfilhos (m2), produção de matéria seca (kg ha-1), altura do dossel forrageiro (cm). Foram coletadas 72 amostras em pontos georreferenciados em terreno declivoso. O solo foi classificado como Neossolo Quartzarênico Órtico na porção superior (Topo), Neossolo Litólico Eutrófico, no terço superior da encosta (ombro), Neossolo Litólico Eutrófico no terço médio da encosta (meia-encosta) e Neossolo Quartzarênico Hidromórfico no terço inferior (pedimento). Todas as variáveis avaliadas apresentaram dependência espacial com variogramas de estrutura bem definida. A pastagem apresentou heterogeneidade na morfologia do dossel em função da distribuição espacial da fertilidade do solo, resultando em dossel e produção de matéria seca mais elevada no topo e atingindo a menor produção no ombro da topossequência. O dossel forrageiro apresenta heterogeneidade na morfologia em função da distribuição espacial da fertilidade do solo e da profundidade efetiva, resultando na definição de duas zonas manejo: 1(AU)

Variabilidade espacial das respostas produtivas e morfológicas do capim-Marandu em função dos atributos químicos e topográficos / Spatial variability of yield response and morphological Marandu grass depending on the chemical and topographical

This work aimed to evaluate the spatial variability of structural and productive responses of Marandu grass depending on the chemical characteristics of the soil and topography. The experiment was conducted in a topossequence, school of Veterinary Medicine and Animal Science, The V variables were evaluated CTC, SB, m, pH at a depth of 0-20 cm, effective depth, number of tillers (m2), production dry matter (kg ha-1), when sward (cm). 72 samples were collected in georeferenced points on sloping ground. The soil was classified as Entisol in the upper portion (top), Udorthent Eutrophic the upper third of the slope (shoulder), Udorthent eutrophic in the middle third of the slope (halfslope) and Quartzips amment Hydromorphic in the lower third (pedimento). All variables presented spatial dependence with variograms of well-defined structure. The pasture presented heterogeneity in the morphology of the canopy due to the spatial distribution of soil fertility, resulting in canopy and producing higher dry matter at the top and reaching the lower production on the shoulder of topossequence. The sward has heterogeneity in morphology depending on the spatial distribution of soil fertility and the effective depth, resulting in the creation of two management areas: 1topo and pediment, and 2 shoulder and half hillside.

Objetivou-se com este trabalho avaliar a variabilidade espacial das respostas produtivas e estruturais do capim Marandu em função das características químicas do solo e da topografia do terreno. O experimento foi conduzido em uma topossequência, na escola de Medicina Veterinária e Zootecnia. Foram avaliadas as variáveis V, CTC, SB, m, pH, na profundidade de 0-20cm, profundidade efetiva, número de perfilhos (m2), produção de matéria seca (kg ha-1), altura do dossel forrageiro (cm). Foram coletadas 72 amostras em pontos georreferenciados em terreno declivoso. O solo foi classificado como Neossolo Quartzarênico Órtico na porção superior (Topo), Neossolo Litólico Eutrófico, no terço superior da encosta (ombro), Neossolo Litólico Eutrófico no terço médio da encosta (meia-encosta) e Neossolo Quartzarênico Hidromórfico no terço inferior (pedimento). Todas as variáveis avaliadas apresentaram dependência espacial com variogramas de estrutura bem definida. A pastagem apresentou heterogeneidade na morfologia do dossel em função da distribuição espacial da fertilidade do solo, resultando em dossel e produção de matéria seca mais elevada no topo e atingindo a menor produção no ombro da topossequência. O dossel forrageiro apresenta heterogeneidade na morfologia em função da distribuição espacial da fertilidade do solo e da profundidade efetiva, resultando na definição de duas zonas manejo: 1

Establishment of pastures under monoculture farming and integrated with biofertilizer using poultry litter as a nutrient source / Implantação de pastagens sob sistema monocultivo e integrado com lavoura utilizando biofertilizante de cama de aviário como adubação de cobertura

The objective was to evaluate the effect of the use of bio-fertilizers obtained by anaerobic biodigestion Aviary bed productive characteristics of Piatã, grass and soil chemical characteristics. Assessed five doses of biofertilizers (0; 10; 20; 30; 40m3. Ha-1) in two cultivation systems (monoculture system of Piatã grass and grass intercropping system with hybrid forage sorghum Piatã BRS 610). Agronomic characteristics were verified and submitted to structural measures of biofertilizer in the two systems of crops, checked also the influence of biofertilizer in soil chemical characteristics. The two production systems responded efficiently with the application of biofertilizer, however the thatched roofs and tilling was the main components responsible for increased productivity. The doses of biofertilizer brought chemical soil characteristics increments, being identified only difference to K+ and organic matter between systems of crops, evidencing the Member with the highest extraction system of soil nutrients by crops. The biofertilizer proved satisfactory considering increments obtained in the production of fodder, in tiller number, leaf area, mass per tiller being good option for improving the productivity of grass Piatã, responding positively in both production systems.(AU)

Objetivou-se avaliar o efeito da utilização de biofertilizante obtido através da biodigestão anaeróbica da cama de aviário nas características produtivas do capim Piatã, e nas características químicas do solo. Avaliou-se cinco doses de biofertilizantes (0; 10; 20; 30; 40m3.ha-1) em dois sistemas de cultivos (sistema monocultivo de capim Piatã e sistema consorciado de capim Piatã com sorgo forrageiro hibrido BRS 610). Foram verificadas as características agronômicas e estruturais submetidas às doses de biofertilizante nos dois sistemas de cultivos, verificado também a influência do biofertilizante nas características químicas do solo. Os dois sistemas de produção responderam de forma eficiente com a aplicação do biofertilizante, porém o colmo e o perfilhamento foram os principais componentes responsáveis pelo aumento de produtividade. As doses de biofertilizante trouxeram incrementos nas características químicas do solo, sendo identificado diferença apenas para K+ e matéria orgânica entre os sistemas de cultivos, evidenciando o sistema consorciado com as maiores extrações de nutrientes do solo pelas culturas. O biofertilizante mostrou ser satisfatório considerando incrementos obtidos na produção de forragem, no número de perfilho, área foliar, massa por perfilho sendo boa opção para melhoria da produtividade do capim Piatã, respondendo de forma positiva nos dois sistemas de produção.(AU)

Establishment of pastures under monoculture farming and integrated with biofertilizer using poultry litter as a nutrient source / Implantação de pastagens sob sistema monocultivo e integrado com lavoura utilizando biofertilizante de cama de aviário como adubação de cobertura

The objective was to evaluate the effect of the use of bio-fertilizers obtained by anaerobic biodigestion Aviary bed productive characteristics of Piatã, grass and soil chemical characteristics. Assessed five doses of biofertilizers (0; 10; 20; 30; 40m3. Ha-1) in two cultivation systems (monoculture system of Piatã grass and grass intercropping system with hybrid forage sorghum Piatã BRS 610). Agronomic characteristics were verified and submitted to structural measures of biofertilizer in the two systems of crops, checked also the influence of biofertilizer in soil chemical characteristics. The two production systems responded efficiently with the application of biofertilizer, however the thatched roofs and tilling was the main components responsible for increased productivity. The doses of biofertilizer brought chemical soil characteristics increments, being identified only difference to K+ and organic matter between systems of crops, evidencing the Member with the highest extraction system of soil nutrients by crops. The biofertilizer proved satisfactory considering increments obtained in the production of fodder, in tiller number, leaf area, mass per tiller being good option for improving the productivity of grass Piatã, responding positively in both production systems.

Objetivou-se avaliar o efeito da utilização de biofertilizante obtido através da biodigestão anaeróbica da cama de aviário nas características produtivas do capim Piatã, e nas características químicas do solo. Avaliou-se cinco doses de biofertilizantes (0; 10; 20; 30; 40m3.ha-1) em dois sistemas de cultivos (sistema monocultivo de capim Piatã e sistema consorciado de capim Piatã com sorgo forrageiro hibrido BRS 610). Foram verificadas as características agronômicas e estruturais submetidas às doses de biofertilizante nos dois sistemas de cultivos, verificado também a influência do biofertilizante nas características químicas do solo. Os dois sistemas de produção responderam de forma eficiente com a aplicação do biofertilizante, porém o colmo e o perfilhamento foram os principais componentes responsáveis pelo aumento de produtividade. As doses de biofertilizante trouxeram incrementos nas características químicas do solo, sendo identificado diferença apenas para K+ e matéria orgânica entre os sistemas de cultivos, evidenciando o sistema consorciado com as maiores extrações de nutrientes do solo pelas culturas. O biofertilizante mostrou ser satisfatório considerando incrementos obtidos na produção de forragem, no número de perfilho, área foliar, massa por perfilho sendo boa opção para melhoria da produtividade do capim Piatã, respondendo de forma positiva nos dois sistemas de produção.

Calcium: magnesium ratio amendments of soil acidity and agronomy characteristics of forage specie / Relação Ca: Mg do corretivo da acidez do solo e as características agronômicas de plantas forrageiras

The variation in the Ca:Mg ratio in amendments used to neutralize soil acidity is way of altering the availability of those nutrients in forage species and properties soil chemists. The objective of work was to evaluate the effect of different proportions of calcium and magnesium in of CaCO3 and MgCO3 on agronomy characteristics on soil chemist properties in forage species in Araguaína city, Tocantins state. The study was carried on Entisol, with factorial 3 x 5 and four replications. The treatments had consisted of ratio application equivalent the 4t/ha of calcareous, using mixtures of CaCO3 and MgCO3 in diverse ratios until reaching relations Ca:Mg of 1:1; 2:1; 4:1, 6:1 and 8:1, applied in Entisol, with 5% of clay, cultivated with three forages species (Brachiaria brizantha cv. Xaraés, Panicum maximum cv: Mombaça e estilosante Campo Grande Stylosanthes capitata e S. macrocephala). The different relations Ca:Mg was however influenced in development and productivity of forages, however was not coherent behavior that indicated the trend of reply of the plants to the increase or reduction of the relation Ca:Mg. Moreover, the different forages were been similar in relation the soil chemistry, however the relations Ca:Mg had modified the chemical soil properties.(AU)

A variação na relação Ca:Mg em corretivos da acidez do solo é a principal forma de alterar a disponibilidade desses nutrientes para as espécies forrageiras. O objetivo com o trabalho foi avaliar o efeito de diferentes proporções entre cálcio e magnésio na forma de CaCO3 e MgCO3 sobre as propriedades químicas do solo e as características agronômicas de espécies forrageiras em Araguaína, TO. O estudo foi sobre Neossolo Quartzarênico Órtico típico, com 5% de argila, com fatorial 3 x 5, sendo três as espécies forrageiras (Brachiaria brizantha cv. Xaraés, Panicum maximum cv: Mombaça e estilosante Campo Grande Stylosanthes capitata e S. macrocephala) e cinco as relações de Ca:Mg no calcário (1:1; 2:1; 4:1, 6:1 e 8:1). Os tratamentos foram dispostos em delineamento em blocos ao acaso, com quatro repetições. Todos os tratamentos receberam dose equivalente de 4t/ha de calcário. As diferentes relações Ca:Mg influenciaram no desenvolvimento e produtividade das forrageiras entretanto, não se obteve comportamento coerente que indicasse a tendência de resposta das plantas ao aumento ou redução da relação Ca:Mg. Além disto, as diferentes forrageiras foram semelhantes em relação a química do solo, porém as relações Ca:Mg alteraram as propriedades químicas do solo.(AU)

Calcium: magnesium ratio amendments of soil acidity and agronomy characteristics of forage specie / Relação Ca: Mg do corretivo da acidez do solo e as características agronômicas de plantas forrageiras

The variation in the Ca:Mg ratio in amendments used to neutralize soil acidity is way of altering the availability of those nutrients in forage species and properties soil chemists. The objective of work was to evaluate the effect of different proportions of calcium and magnesium in of CaCO3 and MgCO3 on agronomy characteristics on soil chemist properties in forage species in Araguaína city, Tocantins state. The study was carried on Entisol, with factorial 3 x 5 and four replications. The treatments had consisted of ratio application equivalent the 4t/ha of calcareous, using mixtures of CaCO3 and MgCO3 in diverse ratios until reaching relations Ca:Mg of 1:1; 2:1; 4:1, 6:1 and 8:1, applied in Entisol, with 5% of clay, cultivated with three forages species (Brachiaria brizantha cv. Xaraés, Panicum maximum cv: Mombaça e estilosante Campo Grande Stylosanthes capitata e S. macrocephala). The different relations Ca:Mg was however influenced in development and productivity of forages, however was not coherent behavior that indicated the trend of reply of the plants to the increase or reduction of the relation Ca:Mg. Moreover, the different forages were been similar in relation the soil chemistry, however the relations Ca:Mg had modified the chemical soil properties.

A variação na relação Ca:Mg em corretivos da acidez do solo é a principal forma de alterar a disponibilidade desses nutrientes para as espécies forrageiras. O objetivo com o trabalho foi avaliar o efeito de diferentes proporções entre cálcio e magnésio na forma de CaCO3 e MgCO3 sobre as propriedades químicas do solo e as características agronômicas de espécies forrageiras em Araguaína, TO. O estudo foi sobre Neossolo Quartzarênico Órtico típico, com 5% de argila, com fatorial 3 x 5, sendo três as espécies forrageiras (Brachiaria brizantha cv. Xaraés, Panicum maximum cv: Mombaça e estilosante Campo Grande Stylosanthes capitata e S. macrocephala) e cinco as relações de Ca:Mg no calcário (1:1; 2:1; 4:1, 6:1 e 8:1). Os tratamentos foram dispostos em delineamento em blocos ao acaso, com quatro repetições. Todos os tratamentos receberam dose equivalente de 4t/ha de calcário. As diferentes relações Ca:Mg influenciaram no desenvolvimento e produtividade das forrageiras entretanto, não se obteve comportamento coerente que indicasse a tendência de resposta das plantas ao aumento ou redução da relação Ca:Mg. Além disto, as diferentes forrageiras foram semelhantes em relação a química do solo, porém as relações Ca:Mg alteraram as propriedades químicas do solo.

Characteristics and classification of the quality and productive standards of the mombaça grass under a livestock-forest system or full sun / Comportamento e classificação dos padrões qualitativos e produtivos do capim mombaça em sistema sivipastoril e pleno sol

The objective of this study is to identify qualitative and productive changes in Mombasa grass under a livestock-forest system or full sun and to classify the variables that are most relevant for evaluating the qualitative performance of these systems. The experiments were conducted in shade areas, with four replications for each of the 12 treatments, including four growth cycles and three levels of shading in Mombasa grass, totaling 48 experimental units. Calcium (Ca), magnesium (Mg), potassium (K), phosphorus (P), nitrogen (N) and dry mass production (DMP) (kg ha-1) were used as discriminatory variables for the shading groups. The levels of nutrients and shading in Mombaça grass were classified using Fisher multivariate discriminant analysis (FMDA). The FDMA indicated that Mg, K, P, N, and DMP formed a discriminant function. However, DMP was the least important variable for identifying the groups. Five groups were pre-defined before FDMA: MFS 2 (Mombasa grass in full sun in the second cycle), MFS 6 (Mombasa grass in full sun in the sixth cycle), MFS 7 (Mombasa grass in full sun in the seventh cycle), M25 4 (Mombasa grass at 25% shading in the fourth cycle), and M25 7 (Mombasa grass at 25% shading in the seventh cycle). The results indicate that Mg, P, K, and N are helpful for identifying new genotypes of plants grown on shading conditions because of the responsiveness and stability of these elements to environmental changes.

Objetivou com este estudo identificar as alterações qualitativas e produtivas do capim Mombaça em sistema silvipastoril e pleno sol, e classificar as variáveis mais estratégicas para avaliação do seu desempenho qualitativo. O ensaio foi alocado em faixas de sombreamento, com quatro repetições para cada um dos 12 tratamentos - quatro ciclos e três porcentagens de sombreamento, em capim Mombaça, totalizando 48 unidades experimentais. Foram usados os macroelementos: cálcio (Ca), magnésio (Mg), potássio (K), fósforo (P) e nitrogênio (N) e Produção de massa seca (PMS) (kg ha-1) como variáveis de discriminação de grupos de sombreamento. A classificação das variáveis e dos níveis de sombreamento enriquecido com mombaça, procedeu-se por meio da Análise Multivariada Discriminante de Fisher (ADF). Foi possível com o auxílio da ADF identificar as variáveis Mg, K, P, N e PMS como significativas para formação da função discriminante. Entretanto, o teor de PMS foi o menos relevante para identificação dos grupos. Cinco grupos foram pré-definidos antes da análise discriminante, MSP 2º (Mombaça pleno sol 2º ciclo), MSP 6º(Mombaça pleno sol 6º ciclo), MSP 7º (Mombaça pleno sol 7º ciclo), M25 4º (Mombaça 25% 4º ciclo) e M25 7º (Mombaça 25% 7º ciclo). Para auxiliar na busca de novos genótipos considerando a concentração de nutrientes em estudos sobre condições de sombreamento, os elementos Mg, P, K e N oferecem grande auxílio pela sua responsividade e estabilidade as oscilações ambientais.

Forage performance and cattle production as a function of the seasonality of a Brazilian tropical region / Forage performance and cattle production as a function of the seasonality of a Brazilian tropical region

This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3 x 3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry, and end of dry season), with repeated measures over time. The following variables were evaluated: canopy height, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitro dry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore), was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction among cultivars and period of the year the similarity in animal performance among the cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.

This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3 x 3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry, and end of dry season), with repeated measures over time. The following variables were evaluated: canopy height, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitro dry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore), was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction among cultivars and period of the year the similarity in animal performance among the cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.