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Morphogenesis of dwarf elephant grass clones in response to intensity and frequency of defoliation in dry and rainy seasons
Gomide, Carlos Augusto de Miranda;Paciullo, Domingos Sávio Campos;Costa, Igor de Almeida;Lima, Aline Medeiros;Castro, Carlos Renato Tavares de;Lédo, Francisco José da Silva;
Revista Brasileira de Zootecnia , 2011, DOI: 10.1590/S1516-35982011000700007
Abstract: the aim of this study was to evaluate during the dry and rainy seasons the morphogenesis traits of two clones of dwarf elephant grass under different management strategies. the study was conducted in a factorial 2 × 2 × 3 design, using two clones, one green and one purple, two residual heights, 25 and 45 cm, and three frequencies of defoliation according to the light interception of 90, 95 and 100%. the design was a randomized block with three replications. the variables were leaf elongation and leaf senescence rate, stem elongation rate and phyllochron. the leaf lifespan and the number of living leaves per tiller were also estimated. the clones presented low stem elongation rates, showing adaptation for grazing use. in the rainy season, the light interception of 100% promoted the highest stem elongation rate and increased the leaf senescence rate. in the dry season, the leaf elongation rate (ler) was higher for the purple clone than for the green one (23 vs 15 mm.tiller-1.day-1). in the rainy season, the ler of the green clone exceeded that of the purple one by 71% (149 vs. 87 mm.tiller-1.day-1). the phyllochron varied among clones only in the rainy season, when the value was 4.6 days.leaf-1 for the green clone and 8.4 days.leaf-1 for the purple one; both of these values are below the mean value observed during the drought (21,6 days.leaf-1). the residual heights did not affect, in an isolated way, any of the variables. the clones are well adapted to grazing, presenting low stem elongation rates. the interval between defoliations should consider the scope of light interception between 90 and 95%. the green clone, with a greater flow of biomass, requires handling with shorter defoliation intervals.
Variabilidade e herdabilidade de caracteres morfológicos em clones de capim-elefante na Zona da Mata de Pernambuco
Silva, Ant?nio Luiz Cordeiro da;Santos, Mércia Virginia Ferreira dos;Dubeux Júnior, José Carlos Batista;Lira, Mario de Andrade;Ferreira, Rinaldo Luiz Caraciolo;Freitas, Erinaldo Viana de;Cunha, Márcio Vieira da;Silva, Maria da Concei??o;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010001000005
Abstract: this research was carried out at to evaluate the variability and heritability of morphologic traits in 54 elephant grass clones (three local controls and 51 from the renace/cnpgl) in the forest zone in pernambuco. it was used a complete randomized block design with additional controls. three cuts were performed on the 60th day of regrowth. there were significant differences for stem diameter, basal and aerial tillers density, width of leaf 3, length of leaf 5, leaf blade percentage, stem percentage, and leaf/stem ratio. clones of renace are similar to the ones traditionally cultivated in the conditions of forest zone in pernambuco regarded to morphological characters. cultivar pioneiro showed early flourishing in the environmental conditions of this study. number of basal and aerial/metter tillers showed good heritability, evidencing little influence of the environment on variability among the clones. considering the variability among renace clones for basal and aerial tillers/m and leaf/stem ratio and the high heritability of these characters, it is possible to obtain genetic gains for these traits in the elephant grass breeding program in the forest zone in pernambuco.
In situ degradability of corn stover and elephant-grass harvested at four stages of maturity
Silva, Luis Felipe Prada e;Cassoli, Laerte Dagher;Roma Júnior, Luiz Carlos;Rodrigues, Ana Carolina de Oliveira;Machado, Paulo Fernando;
Scientia Agricola , 2008, DOI: 10.1590/S0103-90162008000600005
Abstract: among tropical forages, corn silage is largely used by farmers trying to explore the maximum genetic potential from the animals. however, other tropical forages, such as elephant-grass (pennisetum purpureum), are more productive and therefore cheaper to use than corn silage. our objective was to compare the in situ degradability of elephant-grass with that from corn hybrids, all harvested at four stages of maturity. the experimental design followed a randomized block design with nested subplots. two corn hybrids: ag5011, zn8392 were harvested with 25, 30, 35, and 40% dry matter (dm) in the whole plant, and separated in stem + leaf sheath + leaf blade (stover), and cobs. elephant-grass was harvested with 30, 40, 50 and 60 days after a leveling cut. dried and ground samples were incubated in nylon bags inside the rumen for 0, 6, 12, 24, 48 and 72 h to estimate the kinetics of ruminal dm and neutral detergent fiber (ndf) degradation. the advance of maturity increased the ndf and acid detergent fiber (adf) content in elephant-grass, and reduced its dm degradability. however, maturity had little or no effect on fiber content and dm degradability of corn stover. elephant-grass had a higher ndf degradability than corn stover, and there was no effect of maturity on ndf degradability of either elephant-grass or corn stover. fiber degradability of elephant-grass was not worse than that of corn stover, and therefore the choice of forage should be made on economical analysis rather than assuming an intrinsic low production potential for elephant-grass based diets.
Composi o químico-bromatológica do capim-elefante submetido à aduba o química e organica Productive characteristics and chemical-bromatological composition of elephant grass submitted to chemical and organic fertilization  [cached]
Tadeu Silva de Oliveira,José Carlos Pereira,Claúdio Samara dos Reis,Augusto Cesar de Queiroz
Revista Brasileira de Saúde e Produ??o Animal , 2011,
Abstract: Objetivou-se avaliar os efeitos da aduba o química e organica sobre a composi o químico-bromatológica do capim elefante, além de estimar a energia líquida do volumoso e os nutrientes digestíveis totais desta forrageira. Foram formadas duas áreas de capineiras e utilizados dois sistemas de aduba o. Utilizou-se delineamento em blocos (seis períodos), casualizados completos e três repeti es por volumoso (aduba o química e aduba o organica) por bloco. Os dados de proteína bruta, fibra em detergente neutro, cinzas, cálcio, magnésio, potássio e fósforo foram avaliados pelo teste F, a 5% de probabilidade. Com base na fibra em detergente neutro, estimou-se a energia líquida do volumoso e os nutrientes digestíveis totais do capim-elefante nos dois sistemas de aduba o. Com base nos resultados, observa-se que o capim-elefante submetido à aduba o organica apresenta maiores valores em sua composi o químico-bromatológica. Foram observados nesta forragem submetida à aduba o organica, maiores teores de proteína bruta (17,26%), cinzas (26%) e fósforo (36,88%) e menores teores de fibra em detergente neutro (3,96%) em rela o ao capim-elefante submetido à aduba o química. A aplica o de esterco de curral na capineira de capim-elefante melhorou o teor de matéria organica no solo, o que propiciou melhoria na composi o químico-bromatológica, além de proporcionar maior flexibiliza o na frequência de utiliza o da capineira em rela o à adubada químicamente. The objectives of this work were to study the effect of chemical and organic fertilization on the forage dry matter chemical composition characteristics of elephant grass and to estimate the total net energy of forage and the total digestible nutrients. Two elephant grass stocking piles were formed and two fertilization systems were used. Soil and plant evaluations (chemical and physical analysis) were performed at field. Was carried out in a completely block (six periods) randomized design and three replicates per forage (chemical and organic fertilization) per block. Data of crude protein, neutral detergent fiber, and ashes, calcium, phosphorus, magnesium and potassium were evaluated by F test, at 5% of probability. Based on the total digestible nutrients contents, the total net energy and total digestible nutrients of the elephant grass from the two fertilization systems were estimated. The elephant grass submitted to fertilization organic showed higher chemical composition values. In this forage, higher contents of crude protein (17.26%), ashes (26%) and phosphorus (36.88%) and smaller of neutral detergent
Aluminum toxicity tolerance in elephant grass  [cached]
Carlos Eugênio Martins,Fausto de Souza Sobrinho,Fernando Teixeira Gomes,Wadson Sebasti?o Duarte da Rocha
Pesquisa Aplicada & Agrotecnologia , 2010, DOI: 10.5777/655
Abstract: El logro de los cultivares de forrajeras mejoradas, tolerantes a la toxicidad de aluminio, se considera la mejor alternativa para sortear las dificultades expresadas por extensas áreas de suelos ácidos con altas concentraciones de aluminio, presente en Brasil. Por lo tanto, los objetivos de este estudio fueron: a) evaluar el nivel de aluminio en solución nutritiva y la característica más importante de la discriminación de genotipos de pasto elefante; b) verificar la existencia de variabilidad genética entre algunos accesos de pasto elefante de la Embrapa Ganado ABG lácteos para la tolerancia al aluminio, y c) estudiar la interacción del genotipo con los niveles de aluminio. En invernadero se evaluaron 26 genotipos de pasto elefante y cuatro niveles de aluminio (0, 15, 30 y 45 ppm) en un experimento realizado en un dise o completamente al azar con tres repeticiones en contenedores con una planta. Tomó nota de los datos relativos al peso seco del vástago (SDW), peso seco de raíz (PSR), altura de los brotes (APA) y la longitud de las raíces (CR). Con las medias de los genotipos de aluminio diferentes procedió a un análisis de la adaptabilidad y la estabilidad mediante el metodologías de Eberhart y Russell y Annicchiarico. Se ha encontrado que existe variabilidad entre los genotipos de pasto elefante para la tolerancia a los diferentes niveles de aluminio, teniendo en cuenta las características PSPA, PSR, APA y CR. El nivel de 15 ppm de aluminio se consideró los materiales más adecuados para identificar tolerantes y sensibles a los tóxicos de aluminio. Las características PSPA y APA fueron más adecuados para una nueva evaluación de tolerancia de pasto elefante con el aluminio en solución nutritiva. El genotipo Taiwan121 y Australiano se presentaron adaptable y estable en las dos metodologias utilizados. The use of forages with aluminum tolerance is the best alternative to the wide areas of acid soils with high aluminum concentrations in Brazil. So, the goals of this work were: to evaluate the aluminum level in the nutrient solution and the most important characteristics for elephant grass genotypes discrimination; to verify the existence of genetic variability between accesses of elephant grass of BAG Embrapa Gado de Leite for aluminum tolerance, and; to study the genotypes and aluminum levels interaction. In a greenhouse experiment 26 elephant grass genotypes and four aluminum levels (0, 15, 30 e 45 ppm) were tested, using a randomized design, with three replications and only one plant per vase. Data of dry matter of aerial part (DMAP), root dry matter (RDM
Características morfológicas e produtivas do capim-marandu adubado com fosfato natural reativo em solo de cerrado = Morphological and productive characteristics of marandu grass fertilized with natural reactive phosphate in cerrado soil.  [cached]
Edna Maria Bonfim-Silva,Claudia Cardoso dos Santos,Lorraine do Nascimento Farias,Marcella Karoline Cardoso Vilarinho
Agro@mbiente On-line , 2012,
Abstract: O fósforo é importante para o desenvolvimento das plantas, sendo imprescindível para a realiza o dos processos metabólicos. Objetivou-se pelo presente estudo avaliar as características morfológicas e produtivas da Brachiaria brizantha cv. Marandu em fun o de doses de fósforo empregando o fosfato natural reativo Bayóvar (29% de P2O5). O experimento foi realizado em casa de vegeta o na Universidade Federal de Mato Grosso - Campus Universitário de Rondonópolis. O solo utilizado foi o Latossolo Vermelho, coletado na camada de 0-20 cm. Os tratamentos consistiram de seis doses de fósforo (0;50; 100; 150; 200 e 250 mg dm-3) e cinco repeti es utilizando o delineamento experimental inteiramente casualizado. Foram realizados dois cortes (aos 48 dias após a semeadura e 28 dias após o primeiro corte) e as variáveis analisadas foram: altura de planta, número de folhas, número de perfilhos, produ o de massa seca da parte aérea e raiz. Todos os resultados foram submetidos à análise de variancia e de regress o a 5% de probabilidade por meio do programa estatístico Sisvar. As doses de fósforo, adicionadas por meio do fosfato natural reativo, promoveram altera es significativas nas características morfológicas e produtivas do capim-marandu no primeiro corte proporcionando maiores produ es no segundo corte. Para o capim-marandu as doses de fósforo que proporcionaram as maiores alturas correspondem ao intervalo de 162,9 e 203,4 mg dm-3 , sendo as demais variáveis ajustadas ao modelo de regress o linear.Phosphorus is important for plant development, and is indispensable for metabolic processes. The objective of this study was to evaluate the morphological and productive characteristics of Brachiaria brizantha cv. Marandu depending on the doses of P in natural reactive phosphate Bayóvar. The experiment was carried out in a greenhouse at Federal University of Mato Grosso - Campus Rondonópolis. The soil used was a Oxisol which was collected from the layers 0,00-0,20 m. The treatments used were six doses of phosphorus (0; 50; 100; 150; 200 and 250 mg dm-3) and five replications using a randomized experimental design. Two cuts (at 48 days after the sowing and 28 days thereafter) were made and the evaluated variables were: plant height, number of leafs, number of tillers, dry mass of shoot and root. All results were subjected to variance analysis and regression at 5% probability using the statistical program Sisvar. The active phosphate fertilization promoted significant changes in the morphological and productive characteristics of marandu grass at the first cut providing
Evaluation of elephant grass silage with the addition of cassava scrapings
Zanine, Anderson de Moura;Santos, Edson Mauro;Dórea, Jo?o Ricardo Rebou?as;Dantas, Paulo Alfredo de Santana;Silva, Thiago Carvalho da;Pereira, Odilon Gomes;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010001200008
Abstract: the objective of this experiment was to evaluate the effects of adding cassava scrapings on gas and effluent losses, dry matter recovery, ph, contents of n-nh3, organic acids and volatile fatty acids and the bromatological composition of elephant grass silages. it was used a randomized complete design, with four levels of cassava scrapings (0, 7, 15 or 30% natural matter) each one with four replications per level. the grass was cut at 50 days of regrowth and ensiled in 15-l silos, equipped with a bunsen valve to allow gas outflow. the gas losses decreased quadratically with the addition of cassava scrapings, whereas effluent losses decreased linearly. dry matter recovery increased quadratically with the addition of cassava scrapings. dry matter (dm) concentration increased but crude protein (cp), neutral detergent fiber (ndf), acid detergent fiber (adf) and hemicellulose (hem) decreased linearly with the addition of cassava scrapings. the ph value and lactic acid concentration increased quadratically with the addition of cassava scrapings. contents of n-nh3 and butyric acid decreased quadratically with the addition of cassava scrapings, whereas acetic acid content decreased linearly. addition of cassava scrapings reduced gas and effluent losses and improved the fermentation profile of elephant grass silages and the level of 7% already ensures this improvement.
Quantitative and qualitative characteristics of elephant grass (Pennisetum purpureum Schum) clones in the semi-arid lands of Pernambuco (Brazil) Características cuantitativas y cualitativas de clones pasto elefante (Pennisetum purpureum Schum) en las tierras semi-áridas de Pernambuco (Brasil) Características quantitativas e qualitativas de clones de capim-elefante (Pennisetum purpureum Schum) no semi-árido pernambucano (Brasil)
Geane DG Ferreira,Mércia VF Santos,Mário A Lira,Alexandre CL Melo
Revista Colombiana de Ciencias Pecuarias , 2013,
Abstract: Background: the efficient use of good quality forage represents one of many ways to improve animal productivity and, consequently, reduce the feed costs of dairy farming. Between the wide variety of studies aiming to improve the nutritional value of forage, histological studies, allow for both the comparison of species or cultivars and the monitoring of tissue aging within the plant. Objective: the present work aimed to characterize the stem morphology of Pennisetum clones (Itambé IV-46, Itambé I-1.20, Itambé I-1.4, Milheto x Bua u/112-23.4, Cuba-116-29.3, CAC-262-12.102, Roxo of Botucatu x CAC-282-18.29, Taiwan-146-2.6, Itambé I-1.5, Pusa Napier or 419-76 x Bua u/122-11.2, Taiwan-146-2.03, Taiwan-146-2.85, Itambé II-2.46, Pusa Napier or 419-76 x Cuba-116-12.3 and Pusa Napier or 412-76 x Bua u/122-8.22) into three strata (basal, medium and apical) and three tillers of the plant using histological sections. Methods: the material was collected in a previously established area at the Experimental Station of S o Bento do Una at the Agronomic Institute of Pernambuco. The materials were distributed in a completely randomized 15 x 3 x 3 factorial design (14 clones and one hybrid, three layers of stem and three tillers). The samples were collected during the dry season beginning in August 2008. Results: there were significant differences (p<0.05) among the clones evaluated, and the average values for the lignified cells in the cortex region ranged from 2.21 to 4.21 for the Taiwan-146-2.6 and Roxo of Botucatu x CAC-282-18.29 clones; however, this was not different from the other clones in the medullary region. The Itambé II-2.46 clone showed the highest absolute value in the percentage of phloem in the cortex region (2.32%) and a high value, with significant differences, in the medullary region (1.59%) compared to the other clones. Conclusion: the highest values of cellulose in the medium and apical regions of the studied stems represent a benefit to grazing animals. Antecedentes: el uso eficiente de forraje de buena calidad es una de las muchas maneras de mejorar la productividad animal y por lo tanto reducir el costo de la alimentación del ganado lechero. Entre la variedad de estudios que permiten mejorar el valor nutritivo del forraje, los estudios histológicos se destacan, porque permiten tanto la comparación de especies o cultivares y el seguimiento del envejecimiento de los tejidos con la madurez de la planta. Objetivo: el presente trabajo tuvo como objetivo caracterizar la morfología del tallo de los clones de Pennisetum (Itambé IV-46, I-Itambé 1.20, Itamb
Concentrate and crude protein levels in diets for dairy Gyr lineage cows grazing elephant-grass during the rainy season
Teixeira, Rafael Monteiro Araújo;Lana, Rogério de Paula;Fernandes, Leonardo de Oliveira;Oliveira, André Soares de;Campos, José Maurício de Souza;Pimentel, Joabe Jobson de Oliveira;
Revista Brasileira de Zootecnia , 2011, DOI: 10.1590/S1516-35982011000600025
Abstract: the objective of this work was to evaluate the effects of three levels of concentrate (2.0, 4.0 and 6.0 kg/cow/day) and two levels of crude protein (cp) (14 and 16% total dietary dry matter), in comparison to mineral mixture (control) on the intake, apparent digestibility, milk composition and yield and on feed efficiency and use of concentrates of cows grazing elephant grass (pennisetum purpureum, schum) in the rainy season. twenty-one milking gyr cows with average body weight of 426 kg and yield of 13.0 kg of milk/cow/day at 55 days of lactation were distributed in randomized blocks design, with seven diets (treatments) in a 3 × 2 + 1 factorial arrangement and three replications, in a period of 84 days. forage dry matter intake was not influenced by the diets, but total dietary dry matter intake increased by 45% with the inclusion of concentrate in the diet. however, milk yield increased by only 17% (1.76 kg more milk per day) with the use of concentrate. for dairy gyr cows grazing elephant-grass during the rainy season, 2 kg of concentrate/cow/day and 14% of cp in the total diet provided the best productive response without harming body weight.
Avalia??o de clones de capim-elefante (Pennisetum purpureum Schum.) e de um híbrido com o milheto (Pennisetum glaucum (L.) R. Br.) submetidos a estresse hídrico. 1. Parametros morfológicos
Barreto, Glesser Porto;Lira, Mário de Andrade;Santos, Mércia Virgínia Ferreira dos;Dubeux Júnior, José Carlos Batista;
Revista Brasileira de Zootecnia , 2001, DOI: 10.1590/S1516-35982001000100001
Abstract: this trial was carried out to evaluate the morphological characteristics of three elephant grass clones (cameroon, roxo de botucatu and mott) and an elephant grass with pearl millet hybrid (hv-241) submitted to two humidity regimes (with and without water stress). a randomized block design with split plots and three replicates was used. in the main plot, the effect of the humidity regimes was studied, and in the split plot, the different clones. plants submitted to water stress showed lower height, and none of them showed internodes above cutting height (10 cm). as a result of water stress, the plant height reductions were 42.7% (cameroon), 35.05% (roxo de botucatu), 28.54% (hybrid hv-241) and 27.43% (mott). leaf blade length was reduced from 69.9 cm, in the wet treatment, to 50.0 cm in those submitted to water stress, whereas leaf blade width average of water stress plants was less than a half of that in wet treatment plants. water stress did not disturb tillering of cultivars but, in hv-241 hybrid, it reduced both the number of lateral tillers/plant and total number of tillers/plant. in both humidity regimes, hybrid hv-241 was the clone, which showed the largest tillering. it was observed that, except for tillering of cultivars, water stress promoted a reduction on the other morphologic studied parameters.
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