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Search Results: 1 - 10 of 190121 matches for " Mario de Andrade;Dubeux Junior "
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Uso de descritores morfológicos e herdabilidade de caracteres em clones de capim-elefante de porte baixo
Silva, Sharlyton Harysson Barbosa da;Santos, Mércia Virginia Ferreira dos;Lira, Mario de Andrade;Dubeux Junior, José Carlos Batista;Freitas, Erinaldo Viana de;Ferreira, Rinaldo Luiz Caraciolo;
Revista Brasileira de Zootecnia , 2009, DOI: 10.1590/S1516-35982009000800008
Abstract: the experiment was carried out with the objectives to evaluate the use of morphologic descriptor in the characterization and selection of dwarf elephant grass genotypes, and to evaluate the heritability of the evaluated traits. nine dwarf elephant grass clones were used (taiwan a.146 - 2.14, taiwan a.146 - 2.27, taiwan a.146 - 2.37, taiwan a.146 - 2.114, merker méxico - 6.2, merker méxico - 6.5, merker méxico - 6.31, cv. mott, and cnpgl92f198.7) was allotted to a randomized complete block design was used with three replications. the morphologic descriptors were applied every 60 days after the staging cut. a total of five cuts were performed at 60-day intervals using a height of 10 cm from ground level. among the evaluated dwarf elephant grass clones the tallest ones were more desirable, and this trait should be considered at the moment of selection. heritability estimate was high for all evaluated traits of dwarf elephant grass, varying from 66% for sheath wax to 100% for mid-rib color. the taiwan a.146 - 2.37 clone was similar to the mott cultivar. heritability values showed genetic variability among clones, detected at 60 days regrowth. some of the used morphologic descriptors allowed characterization of the evaluated genotypes. the clones taiwan a. 146-2.27, taiwan a. 146-2.37, taiwan a. 146-2.114, and merker méxico 6.31 were the tallest and showed greater total tillering intensity, and were more desirable, presenting greater potential for use under cutting.
Dinamica da associa??o de capim-milh? e capim-de-raiz em pasto diferido
Silva, Marta Gerusa Soares da;Lira, Mario de Andrade;Santos, Mércia Virginia Ferreira dos;Dubeux Junior, José Carlos Batista;Lins, Manuela Menezes;Silva, Camilla Vila Nova Soares;
Revista Brasileira de Zootecnia , 2011, DOI: 10.1590/S1516-35982011001100009
Abstract: this study aimed to evaluate the dynamics of the association of 'capim-de-raiz' (chloris orthonoton doell) and alexandergrass [brachiaria plantaginea (link) hitchc], as for persistence and production. gathering of botanical material, evaluation of botanical composition and forage mass were realized in deferred native pastures. to estimate forage mass, a randomized block design with four treatments was used, consisting of 60, 90, 120 and 150 days of deferring and five replications. the botanical composition was expressed as a percentage of the total. ten families, 15 genera, and 18 species were identified. in the botanical composition from may to august 2007, alexandergrass was the main component from 60 to 90 days, corresponding to 46.75 and 52.09%, respectively. in august 2007, other species participated with 57.75% of the botanical composition. in the assessment of the year 2008, at the end of the deferring period, other species occupied 100% of the botanical composition of pasture. the highest forage mass (kg dm/ha) for alexandergrass (2,736) occurred at 90 days; for other species (3,141) and 'capim-de-raiz' (2,701), it was at 120 days. the use of stockpiled forage should preferably take place after 60 to 90 days of deferring. after a year without interference, 'capim-de-raiz' and alexandergrass decrease participation in the botanical composition of pasture.
Association between the morphological and productive characteristics in the selection of elephant grass clones
Cunha, Márcio Vieira da;Lira, Mario de Andrade;Santos, Mércia Virginia Ferreira dos;Freitas, Erinaldo Viana de;Dubeux Junior, José Carlos Batista;Mello, Alexandre Carneiro Le?o de;Martins, Kalina Gerciane Rodovalho;
Revista Brasileira de Zootecnia , 2011, DOI: 10.1590/S1516-35982011000300004
Abstract: the objectives in this work were to study the association between the morphological and productive characteristics in pennisetum sp. clones, and to identify the morphological characteristics responsible for the productivity in pennisetum cp. clones. the canonical correlations were evaluated and the path analysis was made from the simple genotypic correlation matrix between the morphological and productive characteristics of eight pennisetum sp. clones (taiwan a-146 2.37, taiwan a-146 2.27, taiwan-146 2.114, merker méxico mx 6.31, mott, hv-241, elefante b and iri-381). the canonical correlations were significant at 1% probability by the chi-square test. the first pair of canonic factors, with correlation of 0.9999, related the plants with the highest dry matter content to plants with lower leaf area indexes, light perception and leaf angle. the second pair of canonic factors, with correlation of 0.9999, related the plants with the highest dry matter production to the plants with higher basal tiller density, height, and low green leaf number per tiller. the results of the path analysis indicated that the light interception is determinant in dry matter content expression of pennisetum sp. clones, while the basal tiller density and plant height are responsible for dry matter production in these clones.
Análise de trilha em caracteres produtivos de Pennisetum sob corte em Itambé, Pernambuco
Silva?, M?nica Alixandrina da;Lira, Mario de Andrade;Santos, Mércia Virgínia Ferreira dos;Dubeux Junior, José Carlos Batista;Cunha, Márcio Vieira da;Freitas, Erinaldo Viana de;
Revista Brasileira de Zootecnia , 2008, DOI: 10.1590/S1516-35982008000700007
Abstract: this work aimed to estimate the correlation coefficients, determining the direct and indirect effects (path analysis) of explanatory independent variables on total dry matter production (main dependent variables) of five elephant grass clones in five cuts accomplished at the forest zone of pernambuco. each experimental plot measured 24 m2 with 2 m2 of utile area. there was high correlation between almost all the independent variables and the main variable. the characteristic leaf blade number per tiller, however, explained better the potential of dry matter production and leaf blade dry matter production, acting, respectively, in a direct and indirect way on the explanatory variables.
Características morfológicas e produtivas de leguminosas forrageiras tropicais submetidas a duas frequências de corte
Silva, Valdson José da;Dubeux Junior, José Carlos Batista;Teixeira, Vicente Imbroisi;Santos, Mércia Virgínia Ferreira dos;Lira, Mario de Andrade;Mello, Alexandre Carneiro Le?o de;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010000100013
Abstract: the objective of this research was to evaluate morphological and productive characteristics of forage legumes under two harvest frequencies (28 and 56 days) and 10 cm harvest intensity. the following legume species were evaluated: arachis pintoi (cv. amarillo), clitoria ternatea, calopogonium mucunoides, desmodium ovalifolium (cv. itabela) and stylosanthes guianensis (cvs. bandeirante, cook, mineir?o). a randomized complete design was used in a factorial arrangement (07 legumes × 02 harvest frequencies), with four replications per treatment and the following variables were analyzed: biomass accumulation, number of branches per plant, number of live leaves/plant, root dry matter, nodule number, and nodule matter. shoot and root dry matter accumulation per unit time was similar for the harvests at every 28 or every 56 days, except for arachis, clitoria, and desmodium, which showed greater shoot and root biomass when harvested every 56 days. nodule number and nodule mass differed among legumes, but a greater nodule number was observed when the legumes were harvested every 56 days. live leaf number per plant was greater at 56 days, except for arachis and calopogonium which showed similar values for both frequencies. harvest frequency affected differently the morphologic and productive characteristics of the studied legumes that indicated the need for different management among the varieties tested.
Repetibilidade de variáveis produtivas e qualitativas da forragem e da excreta bovina em pastagem de braquiária
Teixeira, Vicente Imbroisi;Dubeux Jr., José Carlos Batista;Mello, Alexandre Carneiro Le?o de;Lira Jr., Mário de Andrade;Lira, Mario de Andrade;Saraiva, Felipe Martins;
Pesquisa Agropecuária Brasileira , 2011, DOI: 10.1590/S0100-204X2011000600012
Abstract: the objective of this work was to determine the repeatability and the number of the required evaluations to obtain determination coefficient greater than 90% in the productive and qualitative variables of forage and cattle excreta on a signal grass (urochloa decumbens) pasture. the utilized variables were: fecal production, feces mineral composition, herbage mineral composition around dung pads, feces biometry, herbage mass and herbage rejection around dung pads, urinary volume, and urine chemical composition. a fixed rotational stocking was used, with three days of occupation and 32 or 67 days of resting period, during the rainy and dry seasons, respectively. repeatability analyzes were obtained with the software genes, using the principal component method based on the covariance. the repeatability coefficients (r) had high estimates, and the r2 were equal to or greater than 90%, except for herbage mass at 20-40 cm, for the difference between pre-and post-grazing herbage height of herbage grown on dung pad, and for nitrogen concentration in the urine for the treatment with 3,2 animal units per hectare (r<0.50). for r2 above 90%, the number of evaluations required would be 11, 9, and 9, for the variables forage, feces, and urine, respectively.
Decomposi??o de serrapilheira em bosque de sabiá na Zona da Mata de Pernambuco
Freire, Joelma de Lira;Dubeux Júnior, José Carlos Batista;Lira, Mario de Andrade;Ferreira, Rinaldo Luiz Caraciolo;Santos, Mércia Virginia Ferreira dos;Freitas, Erinaldo Viana de;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010000800006
Abstract: the research aimed to evaluate the decomposition of sabiá (mimosa caesalpiniifolia benth) litter fractions by using the nylon bag technique. the following litter fractions were incubated: senescent leaves, leaves at the beginning of mineralization, and branches with diameter up to 20 mm. incubation was performed during periods of 0, 4, 8, 16, 64, 100, and 256 days in 2006 and 2007. the fractions were distributed in a random block design with five replications. it was evaluated the disappearance of biomass, nitrogen (n), and phosphorus (p), concentrations of nitrogen and phosphorus and the carbon/ nitrogen ratio of litter during the periods of incubation. in general, the negative exponential model explained the disappearance of biomass, nitrogen, and phosphorus, however, there was a variation among years and, in some cases, despite of being significant, the models showed a low correlation between predicted and observed data. biomass disappearance rate was slow because only 30% of leaf biomass was mineralized after 256 days of incubation. net nitrogen mineralization showed large variation among years, and it differed among the studied fractions. nitrogen content of the litter increased, on average, until 32 days (leaves) and until 64 days (branches) of incubation followed by stabilization. the linear plateau model was used to explain that process. in the course of the incubation periods, the carbon/nitrogen ration decreased. despite of the high content of nitrogen, the decomposition of sabiá litter is slow, what might reduce the loss of nutrients in the forest, increasing its sustainability and reducing the possible deleterious effects to the environment.
Deposi??o e composi??o química de serrapilheira em um bosque de sabiá
Freire, Joelma de Lira;Dubeux Júnior, José Carlos Batista;Lira, Mario de Andrade;Ferreira, Rinaldo Luiz Caraciolo;Santos, Mércia Virginia Ferreira dos;Freitas, Erinaldo Viana de;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010000800005
Abstract: this research aimed to evaluate the deposition and chemical composition of the components of the existing and deposited litter in a sabiá (mimosa caesalpiniifolia benth) canopy. the experiment was carried out from august 2006 to july 2007. the evaluation of the existing and deposited litter was performed every 28 days using 20 squares with 1m2 randomly allocated and new areas were chosen for each evaluation. the canopy showed plants with an average diameter of 26.8 cm at breast height. monthly deposition of organic matter of leaves and branches during the experimental period was 15,167 kg and 3,373 kg/ha, respectively, and it increased during the highest precipitation period, in a 0.30 relationship with the accumulation, indicating higher accumulation than deposition. leaf proportion was 87% of the total litter, with means of 2.9% of nitrogen and 0.17% of phosphorus. the carbon/nitrogen ratio of leaves was below 30, while carbon/nitrogen ratio of the branches ranged from 30 to 40, proving a better quality for leaves. during the experimental period, deposition of nitrogen through litter was approximately 462 kg/ha and 30 kg/ha for phosphorus. litter deposition is essential for maintenance of soil fertility in a sabiá canopy and it contributes for conservation and sustainability of the canopy.
Estimativa de parametros genéticos sob duas estratégias de avalia??o em híbridos intra e interespecíficos de capim-elefante
Assis, Liz Carolina da Silva Lagos Cortes;Lira, Mario de Andrade;Santos, Mércia Virginia Ferreira dos;Dubeux Júnior, José Carlos Batista;Cunha, Márcio Vieira da;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010001200005
Abstract: the objective of this work was to evaluate the genetic parameters estimated in intra and interespecific hybrid families of elephant grass under two evaluation strategies: per se and genetically stratified mass selection. ten families of intraespecifc hybrids and ten families of interespecific hybrids were used. the characteristics evaluated were the following: plant height, plant agronomic score, dry matter content and dry matter production. it was estimated, for genetic parameters, heritability in the wide sense, variance, genetic and experimental variation coefficient and genetic, phenotypic and environmental correlation. the experiment was evaluated in a random block design with three repetitions. greater genetic variability for the studied characteristics were observed among the interespecific hybrids of elephant grass and pearl millet in comparison to the intraespecifc hybrids of elephant grass. heritability showed higher percentages for per se strategy among the studied hybrids. genetically stratified mass selection is less effective in removing the environmental effects aiming at improving experimental precision.
Consumo de matéria seca e desempenho de novilhas das ra?as Girolando e Guzerá sob suplementa??o na caatinga, na época chuvosa, em Pernambuco, Brasil
Santana, Daniel Fernando Ydoyaga;Lira, Mario de Andrade;Santos, Mércia Virginia Ferreira dos;Ferreira, Marcelo de Andrade;Santos, Djalma Cordeiro dos;Mello, Alexandre Carneiro Le?o de;Dubeux Júnior, José Carlos Batista;Araujo, Gherman Garcia Leal de;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010001000007
Abstract: to estimate dry matter intake and to evaluate variation on live weight of heifers, an experiment was conducted from march to july 2003, with the following supplementation strategies: no supplementation (control), cottonseed cake (1 kg); spineless cactus (10 kg); spineless cactus + 0.5 kg of cottonseed cake (5 kg). dry matter intake of native pasture was not affected by supplementation, but it affected total dry matter intake. intake of total dry matter (dm) differed among breeds with values of 5.44 and 6.75 kg/day, respectively for guzerat and girolando breeds. for animal fed cottonseed cake supplementation, total dm intake was higher than in the control group (no supplementation), however, it was similar for those under spineless cactus and cottonseed cake + spinelles cactus supplementation. daily average body weight gain (517 and 434 g/animal, respectively, for girolando and guzerat groups) did not differ among breeds neither was affected by breed ? supplementation interaction. however, among strategies of suplementation, values were significantly different and they were 412, 620, 371 and 498 g/animal/day, respectively, for control and cottonseed cake suplementation group; spineless cactus; cottonseed cake + spineless cactus. in pernambuco semiarid, 1 kg of cottonseed cake supplementation improved daily average weight gain, regardless to breed of the animal during the rainy season.
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