Methods for estimating forage mass in marandu palisade grass canopies / Métodos para a estimativa da massa de forragem em dosséis de capim-marandu

This study compared three methods for estimating forage mass and its morphological components in canopies of Urochloa brizantha cv. Marandu (marandu palisadegrass). Two experiments were carried out, the fi rst simulating deferment and the second, continuous stocking. In the fi rst experiment, three methods for estimating forage mass (square, row, and tiller methods) were evaluated in different canopies with three initial heights (15, 30, and 45 cm). In the second experiment, two methods for estimating forage mass (square and tiller methods) were evaluated in canopies with three average heights (15, 30, and 45 cm) in summer. The experiments were conducted in a completely randomized design, in a split-plot scheme, with four replications. The plots were canopy heights and the subplots, the forage mass estimation methods. In general, taller canopies have greater forage mass. The tiller method resulted in lower total forage and senescent forage masses than the other methods. The tiller method underestimates total forage and senescent forage masses. The square and line methods are suitable to estimate the pasture total and senescent forage masses.(AU)

Este estudo comparou três métodos para a estimativa das massas de forragem e dos seus componentes morfológicos em dosséis de Urochloa brizantha cv. Marandu (capim-marandu). Dois experimentos foram realizados, sendo o primeiro simulando o diferimento e o segundo, a lotação contínua. No primeiro experimento, foram avaliados três métodos para estimativa de massa de forragem (métodos do quadrado, da linha e do perfilho) em dosséis diferidos com três alturas iniciais (15, 30 e 45 cm). No segundo experimento, foram avaliados dois métodos para estimativa de massa de forragem (métodos do quadrado e do perfilho) em dosséis com três alturas médias (15, 30 e 45 cm) no verão. Os experimentos foram conduzidos em delineamento inteiramente casualizado, em esquema de parcelas subdivididas, com quatro repetições. As parcelas foram as alturas dos dosséis e as subparcela, os métodos de estimativa da massa de forragem. Em geral, os dosséis mais altos apresentam maior massa de forragem. O método do perfilho resultou em massas de forragem total e de forragem senescente inferiores ao demais métodos. O método do perfilho subestima as massas de forragem total e de forragem senescente. Para estimar as massas de forragem total e de forragem senescente do pasto, os métodos do quadrado e da linha são adequados.(AU)

Agromorphological, yield and quality characteristics of two populations of alfalfa developed by mass selection / Características agromorfológicas, produtivas e de qualidade de duas populações de alfafa desenvolvidas por seleção massal

ABSTRACT: This study was designed to test the two alfalfa advanced populations (L-1737 and L-1738) with four control cultivars (Bilensoy-80, Gözlü, Savaş and Plato) for agromorphological, yield and quality properties under irrigated conditions in two various locations in Ankara, Turkey in the years of 2013, 2014, and 2015. The experiments were arranged in a randomized block design with four replications. Results of the study showed that there were statistically significant differences in plant height and stem diameter as well as stem number among the study materials. Statistically significant differences were observed for green forage yield (P < 0.05), while not in dry matter yield among the study materials. The average green forage and dry matter yields were reported as 67.0 t ha-1 and 13. 0 t ha-1, respectively. Green forage and dry matter yields in the advanced populations of L-1737 and L-1738 were 69.2 and 67.4 t ha-1; 13.7 and 13.6 t ha-1, respectively. Those yield values were 6.5 and 3.7%; 4.3 and 3.4% higher in green forage and dry matter yields of the advanced populations of L-1737 and L-1738 compared to the control cultivar Bilensoy-80, respectively. These increases in green forage and dry matter yields were due to the effect of the mass selection method. Statistically significant differences were observed for acid detergent fiber, neutral detergent fiber, and relative feeding value among the study materials, except crude protein contents. It was concluded that the two advanced populations had good adaptation ability, high yield and good quality performance under irrigated conditions and could be used as commercial cultivars.

RESUMO: Este estudo foi desenhado para testar duas populações avançadas de alfafa (L-1737 e L-1738) com quatro cultivares controle (Bilensoy-80, Gözlü, Savaş e Plato) para propriedades agromorfológicas, produtividade e qualidade sob condições irrigadas em dois locais diferentes em Ancara, Turquia, nos anos de 2013, 2014 e 2015. Os experimentos foram dispostos em delineamento de blocos casualizados com quatro repetições. Os resultados do estudo mostraram que houveram diferenças estatisticamente significativas na altura das plantas e diâmetro do colmo, bem como no número de colmos entre os materiais avaliados. Foram observadas diferenças estatisticamente significativas para a produtividade de forragem verde (P < 0.05), enquanto não foram observadas diferenças na produção de matéria seca entre os materiais estudados. As produtividades médias de forragem verde e matéria seca foram de 67.0 t ha-1 e 13.0 t ha-1, respectivamente. Os rendimentos de forragem verde e matéria seca nas populações avançadas de L-1737 e L-1738 foram 69.2 e 67.4 t ha-1; 13.7 e 13.6 t ha-1, respectivamente. Esses valores de rendimento foram 6.5 e 3.7%; 4.3 e 3.4% maiores em rendimentos de forragem verde e matéria seca das populações avançadas de L-1737 e L-1738 em relação à cultivar controle Bilensoy-80, respectivamente. Esses aumentos nos rendimentos de forragem verde e matéria seca foram devidos ao efeito do método de seleção massal. Diferenças, estatisticamente significativas, foram observadas para fibra em detergente ácido, fibra em detergente neutro e valor alimentar relativo entre os materiais estudados, exceto nos teores de proteína bruta. Concluiu-se que as duas populações avançadas apresentaram boa capacidade de adaptação, alta produtividade e bom desempenho em condições irrigadas, podendo ser utilizadas como cultivares comerciais.

Canopeo and GreenSeeker applications as tools to support tropical pasture management / Aplicativos Canopeo e GreenSeeker como ferramentas de apoio ao manejo de pastagens tropicais

ABSTRACT: This study determined whether Canopeo and GreenSeeker measurements in Megathyrsus maximus can estimate plant height, dry matter mass, morphological components, and content of crude protein and neutral detergent fiber at different days of growth. Five plots of 5 × 25m M. maximus grass were defined: subplots of 1×1m were evaluated every three days, in which the pasture shows 3, 6, 9, 12, 15, 18, 21, 24, 27, and 30 days of regrowth. The subplot was evaluated for canopy height and mass accumulation. The canopeo index (CI) obtained at a higher height was lower than those obtained at a smaller height. Higher measurement height increased the normalized difference vegetation index (NDVI) relative to 0.10 m. The highest indexes were observed since 18 d of regrowth. Except for the CI evaluated at 0.10 m of height, the indexes were not correlated to the chemical composition of the forage. The CI and NDVI were positively correlated to plant height, dry matter mass, and leaf index, whereas both were negatively correlated with stalk index. Thus, lower evaluation heights for CI and NDVI can be a good predictor of forage height. Values of 0.83 and 85.8 for NDVI and CI, respectively, indicated an appropriate time to start the grazing of M. maximus.

RESUMO: O presente estudo teve como objetivo avaliar se os índices obtidos com Canopeo e GreenSeeker (NDVI) em Megathyrsus maximum são capazes de estimar altura de plantas, massa de matéria seca, componentes morfológicos e teor de proteína bruta e fibra em detergente neutro em diferentes dias de crescimento. Cinco parcelas de 5 × 25 m de capim M.maximum foram definidas: sub parcelas de 1 × 1 m foram avaliadas a cada três dias, nas quais a pastagem apresenta 3, 6, 9, 12, 15, 18, 21, 24, 27 e 30 dias de rebrota. A sub parcela foi avaliada quanto à altura do dossel e acúmulo de massa. O índice do Canopeo (IC) obtido em maior altura foi menor do que o obtido em menor altura. A maior altura de medição aumentou o NDVI em relação a 0,10 m. Os maiores índices foram observados desde 18 dias de rebrota. Exceto para o IC avaliado a 0,10 m de altura, os índices não foram correlacionados com a composição química da forragem. IC e NDVI correlacionaram-se positivamente com a altura da planta, massa de MS e índice foliar, e negativamente com o índice de colmos. Assim, menores alturas de avaliação para IC e NDVI podem ser um bom preditor da altura da forragem. Valores de 0,83 e 85,8 para NDVI e IC, respectivamente, indicam um momento adequado para o início do pastejo de Megathyrsus maximum.

Agromorphological, yield and quality characteristics of two populations of alfalfa developed by mass selection / Características agromorfológicas, produtivas e de qualidade de duas populações de alfafa desenvolvidas por seleção massal

This study was designed to test the two alfalfa advanced populations (L-1737 and L-1738) with four control cultivars (Bilensoy-80, Gözlü, Savas and Plato) for agromorphological, yield and quality properties under irrigated conditions in two various locations in Ankara, Turkey in the years of 2013, 2014, and 2015. The experiments were arranged in a randomized block design with four replications. Results of the study showed that there were statistically significant differences in plant height and stem diameter as well as stem number among the study materials. Statistically significant differences were observed for green forage yield (P < 0.05), while not in dry matter yield among the study materials. The average green forage and dry matter yields were reported as 67.0 t ha-1 and 13. 0 t ha-1, respectively. Green forage and dry matter yields in the advanced populations of L-1737 and L-1738 were 69.2 and 67.4 t ha-1; 13.7 and 13.6 t ha-1, respectively. Those yield values were 6.5 and 3.7%; 4.3 and 3.4% higher in green forage and dry matter yields of the advanced populations of L-1737 and L-1738 compared to the control cultivar Bilensoy-80, respectively. These increases in green forage and dry matter yields were due to the effect of the mass selection method. Statistically significant differences were observed for acid detergent fiber, neutral detergent fiber, and relative feeding value among the study materials, except crude protein contents. It was concluded that the two advanced populations had good adaptation ability, high yield and good quality performance under irrigated conditions and could be used as commercial cultivars.

Este estudo foi desenhado para testar duas populações avançadas de alfafa (L-1737 e L-1738) com quatro cultivares controle (Bilensoy-80, Gözlü, Savas e Plato) para propriedades agromorfológicas, produtividade e qualidade sob condições irrigadas em dois locais diferentes em Ancara, Turquia, nos anos de 2013, 2014 e 2015. Os experimentos foram dispostos em delineamento de blocos casualizados com quatro repetições. Os resultados do estudo mostraram que houveram diferenças estatisticamente significativas na altura das plantas e diâmetro do colmo, bem como no número de colmos entre os materiais avaliados. Foram observadas diferenças estatisticamente significativas para a produtividade de forragem verde (P < 0.05), enquanto não foram observadas diferenças na produção de matéria seca entre os materiais estudados. As produtividades médias de forragem verde e matéria seca foram de 67.0 t ha-1 e 13.0 t ha-1, respectivamente. Os rendimentos de forragem verde e matéria seca nas populações avançadas de L-1737 e L-1738 foram 69.2 e 67.4 t ha-1; 13.7 e 13.6 t ha-1, respectivamente. Esses valores de rendimento foram 6.5 e 3.7%; 4.3 e 3.4% maiores em rendimentos de forragem verde e matéria seca das populações avançadas de L-1737 e L-1738 em relação à cultivar controle Bilensoy-80, respectivamente. Esses aumentos nos rendimentos de forragem verde e matéria seca foram devidos ao efeito do método de seleção massal. Diferenças, estatisticamente significativas, foram observadas para fibra em detergente ácido, fibra em detergente neutro e valor alimentar relativo entre os materiais estudados, exceto nos teores de proteína bruta. Concluiu-se que as duas populações avançadas apresentaram boa capacidade de adaptação, alta produtividade e bom desempenho em condições irrigadas, podendo ser utilizadas como cultivares comerciais.

Canopeo and GreenSeeker applications as tools to support tropical pasture management / Aplicativos Canopeo e GreenSeeker como ferramentas de apoio ao manejo de pastagens tropicais

This study determined whether Canopeo and GreenSeeker measurements in Megathyrsus maximus can estimate plant height, dry matter mass, morphological components, and content of crude protein and neutral detergent fiber at different days of growth. Five plots of 5 × 25m M. maximus grass were defined: subplots of 1×1m were evaluated every three days, in which the pasture shows 3, 6, 9, 12, 15, 18, 21, 24, 27, and 30 days of regrowth. The subplot was evaluated for canopy height and mass accumulation. The canopeo index (CI) obtained at a higher height was lower than those obtained at a smaller height. Higher measurement height increased the normalized difference vegetation index (NDVI) relative to 0.10 m. The highest indexes were observed since 18 d of regrowth. Except for the CI evaluated at 0.10 m of height, the indexes were not correlated to the chemical composition of the forage. The CI and NDVI were positively correlated to plant height, dry matter mass, and leaf index, whereas both were negatively correlated with stalk index. Thus, lower evaluation heights for CI and NDVI can be a good predictor of forage height. Values of 0.83 and 85.8 for NDVI and CI, respectively, indicated an appropriate time to start the grazing of M. maximus.

O presente estudo teve como objetivo avaliar se os índices obtidos com Canopeo e GreenSeeker (NDVI) em Megathyrsus maximum são capazes de estimar altura de plantas, massa de matéria seca, componentes morfológicos e teor de proteína bruta e fibra em detergente neutro em diferentes dias de crescimento. Cinco parcelas de 5 × 25 m de capim M.maximum foram definidas: sub parcelas de 1 × 1 m foram avaliadas a cada três dias, nas quais a pastagem apresenta 3, 6, 9, 12, 15, 18, 21, 24, 27 e 30 dias de rebrota. A sub parcela foi avaliada quanto à altura do dossel e acúmulo de massa. O índice do Canopeo (IC) obtido em maior altura foi menor do que o obtido em menor altura. A maior altura de medição aumentou o NDVI em relação a 0,10 m. Os maiores índices foram observados desde 18 dias de rebrota. Exceto para o IC avaliado a 0,10 m de altura, os índices não foram correlacionados com a composição química da forragem. IC e NDVI correlacionaram-se positivamente com a altura da planta, massa de MS e índice foliar, e negativamente com o índice de colmos. Assim, menores alturas de avaliação para IC e NDVI podem ser um bom preditor da altura da forragem. Valores de 0,83 e 85,8 para NDVI e IC, respectivamente, indicam um momento adequado para o início do pastejo de Megathyrsus maximum.

Marandu grass pastures with the same average height and different horizontal structures change the feeding behavior of grazing sheep? / Pastos de capim-marandu com mesma altura média e diferentes estruturas horizontais alteram o comportamento ingestivo de ovinos em pastejo?

The objective was to investigate the feeding behavior of sheep in marandu grass (Brachiaria brizantha cv. Marandu) pastures under continuous stocking with the same average height and different horizontal structures. The treatments were composed of less heterogeneous pastures (P-H, 24% coefficient of variation of plant heights and more heterogeneous pastures (P+H, 46% coefficient of variation of plant heights) and the locations of the picket, front and back, were also evaluated. A randomized block design was used, with split plots in space and four replications in two years. Crossbred lambs were used, managed under continuous stocking and variable stocking rate, to maintain average height of pastures at 30 cm. Greater masses of total forage, live leaf, live stem and dead material, and greater time of sheep in rumination, occurred in the front, in relation to the paddock background. In P-H, grazing time (GT) did not vary between regions. In P+H, GT was lower at the front than at the background. Idle time (IT) was similar between P-H and P+H. However, the animals remained more IT in the front than in the background. The feeding behavior of grazing sheep is modified in marandu grass pastures under continuous stocking with the same average height, but with different spatial variability of the vegetation.

Objetivou-se investigar o comportamento ingestivo de ovinos em pastos de capim-marandu (Brachiaria brizantha cv. Marandu) sob lotação contínua com mesma altura média e diferentes estruturas horizontais. Os tratamentos foram compostos de pastos menos heterogêneo (P-H, 24% de coeficiente de variação das alturas das plantas) e pastos mais heterogêneo (P+H, 46% de coeficiente de variação das alturas das plantas), também foi avaliado os locais do piquete, frente e fundo. O delineamento utilizado foi de blocos ao acaso, com parcelas subdivididas no espaço e quatro repetições em dois anos. Foram utilizadas borregas mestiças, manejadas sob lotação continua e com taxa de lotação variável, para manter altura média dos pastos em 30cm. Maiores massas de forragem total, folha viva, colmo vivo e material morto, e maior tempo dos ovinos em ruminação, ocorreram na frente, em relação ao fundo do piquete. No P-H, o tempo em pastejo (TP) não variou entre as regiões. No P+H, o TP foi menor na frente do que no fundo. O tempo em ócio (TO) foi semelhante entre os P-H e P+H. Porém, os animais permaneceram mais TO na frente que no fundo. O comportamento ingestivo de ovinos em pastejo é modificado em pastos de capim-marandu sob lotação contínua com mesma altura média, porém com diferentes variabilidades espaciais da vegetação.

Phyllochron variability and cutting management practices on the agronomic potential of sorghum (Sorghum bicolor (L. ) Moench) / Variabilidade do filocrono e práticas de manejo de corte no potencial agronômico de sorgo (Sorghum bicolor (L. ) Moench)

The phyllochronis an indispensable parameter associated with the potential production of sorghum. Accordingly, management practices applied directly in the sorghum(Sorghum bicolor(L.) Moench)crop, such as the cuttingtechnique, provide the ability of plants to regrowth and reestablish the performance of vegetative and reproductive development based on the stimulation of growth in the photosynthetically active area. Appropriately, the aim of this study wasto evaluate the alterations in phyllochron and leaf emission rate expressed by the implementation of cutting managementpracticesin sorghum plants from high and low-quality seeds. The study was performed in the experimental and didactic area of the Federal Institute of Rio Grande do Sul (IFRS) ­Ibirubá, Rio Grande do Sul, Brazil. The experimental design was completely randomized and the treatments were plants from higher (HQS) and lower (LQS) quality seeds and two season crops (2015/16 and 2016/17) with eight replications. The mean phyllochron (°C day leaf-1), height (cm), main stem diameter (cm), number of nodes, dry mass (kgha-1), and number of tillers were evaluated as a strategyto verify the performance of each treatment. Furthermore, meteorologicaldata obtained from an automatic station was required to calculate phyllochron and the evapotranspiration (ETc). Finally, this study indicatedthat the diameter of the stem and tillers is directly associatedto the accumulation of a dry mass of the crop, based on the results of biomass productivity. Moreover, it was demonstratedthat forage sorghum plants derived from HQSindicateda higher capacity to accumulate photoassimilates, stimulating the production of dry mass.(AU)

O filocrono é um parâmetro indispensável associado ao potencial de produção do sorgo. Nesse sentido, práticas de manejo aplicadas diretamente na cultura do sorgo(Sorghum bicolor(L.) Moench), como a técnica de cortes, proporcionam a capacidade das plantas de rebrotar e restabelecer o desempenho do desenvolvimento vegetativo e reprodutivo das plantas a partir do estímulo do crescimento da área fotossinteticamente ativa. Apropriadamente, o objetivo deste estudo foi avaliar as alterações no filocrono e na taxa de emissão foliar expressas pela implementação do manejo de corte em plantas de sorgo a partir de sementes de alta e de baixa qualidade. O estudo foi realizado na área experimental e didática do Instituto Federal do Rio Grande do Sul (IFRS) ­Ibirubá, Rio Grande do Sul, Brasil. O delineamento experimental foi inteiramente casualizado e os tratamentos foram plantas provenientes de sementes de qualidade superior (SQS) e inferior (SQI) e duas safras (2015/16 e 2016/17) com oito repetições. O filocrono médio (°C dia folha-1), altura (cm), diâmetro do caule principal (cm), número de nós, massa seca (kg ha-1) e número de perfilhos foram avaliados como estratégia para verificar o desempenho de cada tratamento. Além disso, dados meteorológicos obtidos de uma estação automática foram necessários para calcular o filocrono e a evapotranspiração (ETc). Finalmente, este estudo indicou que o diâmetro do caule e perfilhos está diretamente associado ao acúmulo de massa seca da cultura, com base nos resultados de produtividade de biomassa. Além disso, foi demonstrado que plantas de sorgo forrageiro derivadas de SQS apresentaram maior capacidade de acumular fotoassimilados, estimulando a produção de massa seca.(AU)

Bioagents and mix of cover plants affecting soybean / Bioagentes e mix de plantas de cobertura afetando a soja

The search for cultivation practices that provide productive, social and environmental benefits to the agroecosystem isof great importance for the sustainable intensification of agriculture. The objective of this study was to determine the effect of multifunctional microorganisms (MM) and mix of cover crops on gas exchange, production components and grain yield of soybean. In the field experiment, conducted by two growing seasons, the experimental design of randomized blocks in factorial scheme 8x2 was used, with four replications. The treatments were composed by the combination of eight vegetal cover and the use or not of MM. The vegetal cover were composed of: 1. Fallow, 2. Corn, 3. Mix 1 (white lupine, buckwheat, white oats, black oats, Crotalaria ochroleuca, C. juncea, turnip, coracana grass, white lupine), 4. Mix 2 (millet, C. ochroleuca, black oats, white oats, buckwheat, coracana grass), 5. Mix 3 (Millet, C. ochroleuca, black oats, white oats, buckwheat, coracana grass), 6. Mix 4 (C. spectabilis, buckwheat, millet and C. breviflora), 7. Mix 5 (oats, buckwheat, millet, piatã grass and C. Ocholeuca); and 8. Mix 6. (black oats, turnip forage, white lupine, coracana grass, buckwheat). The MM consortium used was Serratia marcenses(BRM 32114) + Bacillus sp.(BRM 63573). Soybean plants coinoculated with (BRM 32114) + (BRM 63573) showed an increase in photosynthetic rate (16.65%), stomatal conductance (37.50%), internal CO2concentration (10%), number of pods per plant (15%), mass of 100 grains (4.04%) and grain yield (14.83%). However, no differences were observed in soybean plants grown in succession to the mix of cover crops, except for the number of grains per pod. Therefore, in this study, the highlight was the consortium of multifunctional microorganisms, technology considered strategic for the sustainable intensification of agriculture.(AU)

A busca por práticas de cultivo que proporcionem benefícios produtivos, sociaiseambientaisao agroecossistemaé de grande importância para aintensificação sustentável da agricultura. O objetivo deste estudo foi determinar o efeito demicrorganismos multifuncionais (MM)emix de plantas decoberturasobre as trocas gasosas, componentes de produção e produtividadede grãosdasoja. Noexperimento de campo, conduzido por duas safras agrícolas,utilizou-se o delineamento experimental de blocos casualizados em esquema fatorial 8x2, com quatro repetições. Os tratamentos foram compostos pelacombinação de oito coberturas vegetaise do usoou não MM. As coberturasvegetais foram compostas de:1. Pousio; 2. Milho; 3. Mix 1 (Tremoço Branco, Trigo Mourisco, Aveia Branca, Aveia Preta, Crotalariaochroleuca, C.Juncea, Nabo Forrageiro, Capim coracana)4. Mix 2 (trigo Mourisco, C.spectabiliis, nabo forrageiro, aveia preta); 5. Mix 3 (Milheto, C. ochroleuca, aveia preta, aveia branca, trigo mourisco, Capim coracana); 6. Mix 4 (C. spectabilis, trigo mourisco, milheto e C.breviflora); 7. Mix 5 (Aveia, Trigo Mourisco, Milheto, Piatãe C.ocholeuca); e 8. Mix 6.(Aveia preta, Nabo Forrageiro, Tremoço Branco, Capim coracana, Trigo Mourisco). O consórciode MM utilizadofoi Serratiamarcenses(BRM 32114) + Bacillussp.(BRM63573). Plantas de soja coinoculadas com (BRM 32114) + (BRM63573)apresentaram aumento na taxa fotossintética (16,65%), condutância estomática (37,50%),concentração interna de CO2(10%), número de vagens por planta (15%),massa de 100 grãos (4,04%) e produtividade de grãos (14,83%). Contudo, não foram observadas diferenças nasplantas de soja cultivadasem sucessão aos mix de plantas de cobertura, com exceção do número de grãos por vagem.Portanto, nesse estudo, o destaque foi para o consórcio de microrganismos multifuncionais, tecnologiaconsideradaestratégica para a intensificação sustentável da agricultura.(AU)

Efeito residual de estratégias de adubação sobre características produtivas do capim mombaça no período seco / Residual effect of fertilization strategies on productive characteristics ofmombaça grass in the dry season / Efecto residual de las estrategias de fertilización sobre las características productivas de la hierba mombaça en el período seco

Objetivou-se avaliar o efeito residual de diferentes recomendações de adubação e momentos deaplicação de adubação nitrogenada após a desfolhação sobre as características morfogênicas, estruturais e produtivas do Megathyrsus maximuscv. Mombaça no período seco do ano. Utilizou-se o delineamento em blocos casualizados em esquema fatorial 4 x 3, com 4 repetições. Os tratamentos foram constituídos pelas recomendações de adubação: Manual 5ª aproximação (5AP), Manual do Pará (MP), Reposição de nutrientes (RP) e modelo adaptado de Michaelis e Menten (MM) em três momentos de aplicação da fonte de nitrogênio (N) após desfolhação (dia 0, 3 e 6). As adubações com N foram realizadas no período das águas e no período de transição. A estratégia 5AP com N no dia 0 apresentou os maiores valores para massa seca de lâmina foliar (MSLF) e número de folhas vivas e osmenores para taxa de senescência foliar e massa seca de material morto. Já a recomendação MP com N no dia 6 apresentou os maiores valores para MSLF. A adubação nitrogenada no final do período das águas, promove aumento do comprimento médio de lâmina foliar e do número de folhas vivas além de promover redução de material morto da forragem no período seco.(AU)

The objective was to evaluate the residual effect of different fertilization recommendations and nitrogen application times after defoliation on the morphogenic, structural and productive characteristics of Megathyrsus maximuscv. Mombaça in the dry period of the year. A randomized block design was used in a 4 x 3 factorial scheme, with 4 replications. The treatments were constituted by the fertilization recommendations: 5thApproach Guide(5AP), Pará Guide(PG), Nutrient Replacement(RP) and theMichaelis and Menten adapted model(MM) applied for three days after application of the nitrogen (N) source following defoliation (days 0, 3, and 6). Fertilizations with N were carried out in the rainy season and in the transition period. The 5AP strategy with N on day 0 showed the highest values for leaf blade dry mass (LBDM) and number of live leaves and the lowest values for leaf senescence rate and dead material dry mass. The PG recommendation with N on day 6 presented the higher values for LBDM. Nitrogen fertilization at the end of the wet season promotes an increase in the average length of leaf blade and in the number of live leaves, in addition to promoting a reduction in forage dead material in the dry season.(AU)

El objetivo fue evaluar el efecto residual de diferentes recomendaciones de fertilización y tiempos de aplicación de la fertilización nitrogenada después de la defoliación sobre las características morfogénicas, estructurales y productivas de Megathyrsus maximus cv. Mombasa en el período seco del año. Se utilizó un diseño de bloques al azar en un esquema factorial 4 x 3, con 4 repeticiones. Los tratamientos estuvieron constituidos por las recomendaciones de fertilización: Manual 5º aproximación (5AP), Manual do Pará (MP), Reposición de nutrientes (RP) y modelo adaptado de Michaelis y Menten (MM) en tres momentos de aplicación de la fuente de nitrógeno (N) después de la defoliación (día 0, 3 y 6). Las fertilizaciones con N se realizaron en la época de lluvias y en el período de transición. Laestrategia 5AP con N en el día 0 mostró los valores más altos de masa seca del limbo foliar (MSLF) y número de hojas vivas y los valores más bajos de tasa de senescencia foliar y masa seca de material muerto. La recomendación MP con N en el día 6 presentóvalores superiores para MSLF. La fertilización nitrogenada al final de la estación lluviosa promueve un aumento en la longitud promedio de la lámina foliar y el número de hojas vivas, además de promover una reducción en la materia muerta del forraje en laestación seca.(AU)

Legume inclusion or nitrogen fertilization on Aruana grass overseeded with temperate grasses: Performance, carcass characteristics, and fatty acid profile of the meat of beef steers

The objective of our study was to evaluate the effect of the use of legume (Arachis pintoi) or nitrogen fertilization on animal performance, characteristics of carcass and meat, and fatty acids profile of crossbred steers on Megathyrsus maximus cv. Aruana pasture, overseeded with temperate grasses. The experimental design was completely randomized, with three treatments and three replicates. The experiment was carried out from June to October (127 d). The treatments were: Low-N: 100 kg of N/ha; Medium-N: 200 kg of N/ha; and Legume: Arachis pintoi + 100 kg of N/ha. The pasture with higher nitrogen fertilization (N200) showed a more significant forage mass yield. The mixed grass with legumes presented a higher concentration of saturated fatty acids and saturated:unsaturated ratio in the meat. However, the grass pastures resulted in a higher content of unsaturated fatty acids in the meat. The other pasture variables, and characteristics of carcass and meat were not influenced by the treatments. The increase in nitrogen fertilization, from 100 to 200 kg/ha, and Arachis pintoi mixed with Aruana grass pasture overseeded with black oat and ryegrass does not affect the daily weight gain and the carcass and meat characteristics of the steers. The grass-legume mixture decreases the total concentration of unsaturated fatty acids in meat without influencing the concentration of polyunsaturated fatty acids.(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.

Twenty-five-centimeter pre-grazing canopy height in palisade grass and forage peanut

ABSTRACT: Short-term grazing behavior variables are sensitive to the canopy structure and have an impact on daily forage intake. This study evaluated the effect of pre- and post-grazing canopy heights on the forage harvesting process at a patch scale in a mixture of Brachiaria brizantha (Hochst. ex A. Rich.) Stapf. syn. Urochloa brizantha R.D. Webster cv. Marandu (palisade grass) and Arachis pintoi Krapov. & W.C. Greg. cv. Belomonte (forage peanut). Treatments were allocated to a split-plot arrangement in a completely randomized design. The plots, in their entirety, consisted of two pre-grazing canopy heights: 25 cm (CH25) and 35 cm (CH35); subplots consisted of three levels of defoliation severity: no defoliation (DS0); 20% depletion of pre-grazing canopy height (DS20); and 40% depletion of pre-grazing canopy height (DS40), with eight replications. Heifers were allowed to graze the patches (0.7 × 0.7 m) and their grazing behavior was recorded. Canopy structure measurements were taken both before and after grazing. Patches from CH35 presented greater stem mass for grass (p = 0.001) and legume (p = 0.002) than did patches from CH25. Bite rate, bite mass and instantaneous intake rate were greater for CH25 than for CH35 (p 0.001, p = 0.068, and p = 0.074), and bite mass and instantaneous intake rate were lower for DS20 compared to DS0 (p = 0.032 and p = 0.016). Greater stem mass in the grazing strata negatively influenced the instantaneous intake rate.

Morphometry, productivity and bromatological analisis of purple elephant grass according to nitrogen fertilization / Morphometry, productivity and bromatological analisis of purple elephant grass according to nitrogen fertilization

The objective was to evaluate the morphometric, productive and chemical aspects of purple elephant grass as a function of nitrogen fertilization. The treatments consisted of applying 0, 20, 40, 60, and 80 kg ha-1 of N, using a randomized block design, with five treatments and four replications. The following were evaluated: plant height, number, length and leaf mass, stem diameter and mass, leaf/stem ratio, production of green and dry mass, support capacity for dairy cows, crude protein, neutral detergent fiber and mineral matter. The data were submitted to analysis of variance and Tukey's test at 5% probability. The increase in N doses did not affect (p < 0.05) the morphometry of the purple elephant grass, however it positively stimulated the productivity, the animal support capacity and the bromatological components of the harvested material. The lack of response to nitrogen fertilization may be related to the edaphocilimatic conditions during the experiment and efficiency in the use of N of the variety used. The results demonstrate the high demand of the cultivar for N, actively interfering in the forage yield.

The objective was to evaluate the morphometric, productive and chemical aspects of purple elephant grass as a function of nitrogen fertilization. The treatments consisted of applying 0, 20, 40, 60, and 80 kg ha-1 of N, using a randomized block design, with five treatments and four replications. The following were evaluated: plant height, number, length and leaf mass, stem diameter and mass, leaf/stem ratio, production of green and dry mass, support capacity for dairy cows, crude protein, neutral detergent fiber and mineral matter. The data were submitted to analysis of variance and Tukey's test at 5% probability. The increase in N doses did not affect (p < 0.05) the morphometry of the purple elephant grass, however it positively stimulated the productivity, the animal support capacity and the bromatological components of the harvested material. The lack of response to nitrogen fertilization may be related to the edaphocilimatic conditions during the experiment and efficiency in the use of N of the variety used. The results demonstrate the high demand of the cultivar for N, actively interfering in the forage yield.

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)

Twenty-five-centimeter pre-grazing canopy height in palisade grass and forage peanut

Short-term grazing behavior variables are sensitive to the canopy structure and have an impact on daily forage intake. This study evaluated the effect of pre- and post-grazing canopy heights on the forage harvesting process at a patch scale in a mixture of Brachiaria brizantha (Hochst. ex A. Rich.) Stapf. syn. Urochloa brizantha R.D. Webster cv. Marandu (palisade grass) and Arachis pintoi Krapov. & W.C. Greg. cv. Belomonte (forage peanut). Treatments were allocated to a split-plot arrangement in a completely randomized design. The plots, in their entirety, consisted of two pre-grazing canopy heights: 25 cm (CH25) and 35 cm (CH35); subplots consisted of three levels of defoliation severity: no defoliation (DS0); 20% depletion of pre-grazing canopy height (DS20); and 40% depletion of pre-grazing canopy height (DS40), with eight replications. Heifers were allowed to graze the patches (0.7 × 0.7 m) and their grazing behavior was recorded. Canopy structure measurements were taken both before and after grazing. Patches from CH35 presented greater stem mass for grass (p = 0.001) and legume (p = 0.002) than did patches from CH25. Bite rate, bite mass and instantaneous intake rate were greater for CH25 than for CH35 (p < 0.001, p = 0.068, and p = 0.074), and bite mass and instantaneous intake rate were lower for DS20 compared to DS0 (p = 0.032 and p = 0.016). Greater stem mass in the grazing strata negatively influenced the instantaneous intake rate.

Performance supplementation and ingestive behavior of sheep finished in continuous pasture in the period of water restriction

The objective was to evaluate the performance and ingestivebehavior of grazing sheep in the finishing stage, with supplementation in the period of water restriction. Fifteen male crossbred sheep were used in continuous pasture in Massai grass and supplied supplement formulated with 18% of crude protein in three levels (0.0; 0.3 and 0.6% of body weight), individually. Bromatological and fodder production analyses were performed, as well as foliar mass production, stem mass and senescent material mass. The performance and ingestive behavior of the animals were evaluated. The design was in four randomized blocks for the variables measured in the fodder. For the biometry, weight gain and behavior variables measured in the animals, the design was entirely randomized with five repetitions. The total forage mass production was 5512.41 kg ha-1, with 6.58% of crude protein, 79 38% of neutral detergent fiber and with 65% of foliar mass. The total weight gain and daily weight gain were higher in animals that received a supplement of 0.6% of body weight. In general, the animalsgrazed more in the morning period and the supplemented ones destined more time for rumination and leisure than the ones not supplemented.(AU)

Sward structure, morphological components and forage yield of massai grass in response to residual effect of swine biofertilizer

The present study aimed to evaluate the residual effects of the application of biofertilizer and mineral fertilizer on sward structure and morphological components of Panicum maximumcv. Massai. The experimental design comprised randomized blocks with six treatments consisting of increasing dosesof swine biofertilizer (0, 10, 20, 30 and 40 Mg ha-1) and mineral fertilization (150 kg N ha-1, 33 kg P ha-1), with four replicates. The variables analyzed were pasture height, light interception, leaf area index, forage mass and morphological components.Plant height responded linearly and positively to biofertilizer levels in the three evaluations. The highest averages for light interception (51.63%) and leaf area index (1.64) were observed for the 240 days (40 Mg ha-1). Dry leaf mass was influenced by the increase in biofertilizer dose, with increments of 39.68%, 25.07% and 44.66% for the 240, 300 and 360 days, respectively, when compared to the control treatment. Mineral fertilization promoted lower mass of dead material and lower leaf area index but did not differ from biofertilizer for the other variables. The residual effect of swine biofertilizer was greater than that of mineral fertilization, with a minimum use of 20 Mg ha-1a practical agronomic recommendation.(AU)

Forage production, morphogenetic and structural components, and nutritional value of tropical grasses in the semiarid condition / Produção de forragem, componentes morfogênicos e estruturais e valor nutricional de gramíneas tropicais em condição semiárida

The objective of this study was to evaluate the forage mass, morphogenetic and structural characteristics, and nutritional value of tropical forage grasses in semiarid conditions. Nine grasses were evaluated, namely, three cultivars of Urochloa brizantha (Marandu, MG4, and Piatã); Urochloa decumbens cv. Basilisk; Urochloa humidicola cv. Llanero; Urochloa ruziziensis cv. Kennedy; and three cultivars of Megathyrsus maximum (Massai, Mombaça, and Tanzania). The experiment was laid out in a randomized complete block design in a split-plot arrangement in which the main factor were the grass cultivars and the secondary factor the seasons, with five replications per treatment. The statistical model included the fixed effect of treatment (grass), whereas the season was included as a random effect within treatments. Urochloa brizantha cvs. Marandu, MG4, and Piatã and Urochloa decumbens cv. Basilisk produced on average 858 kg ha-1 more forage mass than cvs. Kennedy and Basilisk. Megathyrsus maximum cv. Mombaça produced 40% more forage mass than the other cultivars of M. maximum (4205 vs. 3001 kg ha-1). Urochloa ruziziensis cv. Kennedy showed the lowest water use efficiency (36%). Urochloa ruziziensis cv. Kennedy exhibited the lowest leaf weight among the Urochloa cultivars (740 vs. 1319 kg ha-1). There was no treatment effect for leaf weight in the M. maximum cultivars. Urochloa ruziziensis cv. Kennedy showed the highest values of total digestible nutrients and dry matter digestibility (1.84 and 2.34%, respectively) among the other Urochloa cultivars. The M. maximum cultivars showed little differences in nutritional values. Cultivars Marandu, Piatã, and Massai exhibited better productive responses in the edaphoclimatic conditions of this study. However, future studies must be conducted evaluating the adaptation of the forage grass under semiarid conditions. Considering the settings of this study, the grasses Urochloa brizantha cvs. MG4, Marandu, and Piatã, as well as Megathyrsus maximum cvs. Massai and Mombaça, can be used in the semiarid condition.

O objetivo deste estudo foi avaliar a produtividade, características morfogênicas e estruturais e valor nutritivo de gramíneas forrageiras tropicais em condições semiáridas. Nove gramíneas foram avaliadas: Três cultivares de Urochloa brizantha (Marandu, MG4 e Piatã), Urochloa decumbens cv. Basilisk, Urochloa humidicola cv. Llanero, Urochloa ruziziensis cv. Kennedy e três cultivares de Megathyrsus maximum (Massai, capim-Mombaça e Tanzânia). O experimento foi conduzido em blocos completos casualizados em esquema de parcelas subdivididas com o fator principal (cultivar) e o fator secundário (estação) com cinco repetições por tratamento. O modelo estatístico incluiu o efeito fixo de tratamento (cultivar), e a estação do ano foi incluída como efeito aleatório dentro do tratamento. Urochloa brizantha cv. Marandu, MG4 e Piatã e Urochloa decumbens cv Basilisk produziram em média 858 kg ha-1 de massa de forragem a mais que a cv. Kennedy e Llanero. Megathyrsus cv. Mombaça produziu 40% (4205 vs. 3001 kg ha-1) a mais de massa de forragem do que as demais cultivares de Megathyrsus maximum. Urochloa ruziziensis cv. Kennedy apresentou a menor (36%) eficiência no uso da água (EUA). Urochloa ruziziensis cv. Kennedy produziu menor quantidade de folhas (740 vs. 1319 kg ha-1) para as demais cultivares de Urochloa. Não houve efeito do tratamento na produtividade de folhas para as cultivares Megathyrsus maximum. Urochloa ruziziensis cv. Kennedy apresentou os maiores valores de nutrientes digestíveis totais (NDT) e digestibilidade da matéria seca (DMS) (+1,84 e 2,34%, respectivamente) em relação à outra cultivar de Urochloa. As cultivares Megathyrsus maximum tiveram pouco efeito sobre os valores nutritivos. As cultivares Marandu, Piatã e Massai apresentaram melhores respostas produtivas nas condições edafoclimáticas deste estudo. No entanto, estudos futuros devem ser realizados avaliando a adaptação da forrageira em condições semiáridas. Nesta condição de estudo, as gramíneas Urochloa brizantha cv. MG4, Marandu e Piatã, assim como o Megathyrsus maximum cv. Massai e Mombaça podem ser usados em condições semiáridas.

Twenty-five-centimeter pre-grazing canopy height in palisade grass and forage peanut

Short-term grazing behavior variables are sensitive to the canopy structure and have an impact on daily forage intake. This study evaluated the effect of pre- and post-grazing canopy heights on the forage harvesting process at a patch scale in a mixture of Brachiaria brizantha (Hochst. ex A. Rich.) Stapf. syn. Urochloa brizantha R.D. Webster cv. Marandu (palisade grass) and Arachis pintoi Krapov. & W.C. Greg. cv. Belomonte (forage peanut). Treatments were allocated to a split-plot arrangement in a completely randomized design. The plots, in their entirety, consisted of two pre-grazing canopy heights: 25 cm (CH25) and 35 cm (CH35); subplots consisted of three levels of defoliation severity: no defoliation (DS0); 20% depletion of pre-grazing canopy height (DS20); and 40% depletion of pre-grazing canopy height (DS40), with eight replications. Heifers were allowed to graze the patches (0.7 × 0.7 m) and their grazing behavior was recorded. Canopy structure measurements were taken both before and after grazing. Patches from CH35 presented greater stem mass for grass (p = 0.001) and legume (p = 0.002) than did patches from CH25. Bite rate, bite mass and instantaneous intake rate were greater for CH25 than for CH35 (p < 0.001, p = 0.068, and p = 0.074), and bite mass and instantaneous intake rate were lower for DS20 compared to DS0 (p = 0.032 and p = 0.016). Greater stem mass in the grazing strata negatively influenced the instantaneous intake rate.