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Morphogenetic and tillering dynamics in Tanzania grass fertilized and non-fertilized with nitrogen according to season
Roma, Cláudio Fabrício da Cruz;Cecato, Ulysses;Soares Filho, Cecílio Viega;Santos, Geraldo Tadeu dos;Ribeiro, Ossival Lolato;Iwamoto, Bruno Shigueo;
Revista Brasileira de Zootecnia , 2012, DOI: 10.1590/S1516-35982012000300013
Abstract: the objectives of this study were to evaluate morphogenetic characteristics and tillering dynamics in tanzania grass fertilized and non-fertilized with nitrogen, under intermittent grazing, in the spring and the summer. the main plots were composed of four nitrogen rates (0, 100, 200 and 300 kg/ha) and the subplots were growth seasons: spring (october, november and december) and summer (january, february and march). the experimental design was of randomized block with plots subdivided by time (seasons of the year) and four replications. urea was used as nitrogen supply and was divided into two applications: one in the spring and another in the summer. the experimental units fertilized with n rates of 200 and 300 kg/ha showed six cycles of pasture, with an average of 27 days of pasture interval, while the treatments with no fertilization and 100 kg/ha of n showed only four and five cycles of pasture, respectively. leaf elongation rate (ler) and the leaf appearance rate (lar) increased linearly with increasing of n rates. the greatest population density occurred in summer with the higher nitrogen rates. the treatment without n fertilization showed the lowest growth of tiller population, while the other treatments exhibited growth rates above 50% when compared with non-fertilized samples. nitrogen rates significantly affect the leaf appearance rate and the leaf elongation rate, as well as the number of live leaves in plants of tanzania grass in both spring and summer.
Structural characteristics of tiller age categories of continuously stocked marandu palisade grass swards fertilized with nitrogen
Paiva, Adenilson José;Silva, Sila Carneiro da;Pereira, Lilian Elgalise Techio;Guarda, Vitor Del'álamo;Pereira, Priscila de Mesquita;Caminha, Fábio Olegário;
Revista Brasileira de Zootecnia , 2012, DOI: 10.1590/S1516-35982012000100004
Abstract: the objective of this experiment was to evaluate the structural characteristics of young, mature and old tillers on continuously stocked marandu palisade grass maintained at 30 cm and fertilized with nitrogen. treatments corresponded to three nitrogen application rates (150, 300 and 450 kg/ha of n) plus control (no fertilization) and were assigned to experimental units (1,200-m2 paddocks) according to a completely randomized block design, with four replications. measurements were performed during fall/winter 2007 and summer 2008. during summer, young tillers showed longer leaves and shorter stems relative to old tillers. during fall/winter, young and old tillers showed shorter leaves, while mature and old tillers showed longer stems. tiller age interfered with the number of leaves per tiller mainly through variations in the number of expanding and senescing leaves during both fall/winter and summer. the structural characteristics of individual tillers are affected by plant age, with nitrogen favouring the production of leaf tissue in young tillers during summer.
Tiller population density and productivity in tall fescue and prairie grass swards
Scheneiter,Jorge; Assuero,Silvia;
Ciencia e investigación agraria , 2010, DOI: 10.4067/S0718-16202010000200004
Abstract: this study examined the relationship between herbage mass and tiller population density in terms of size/density compensation theory, in tall fescue (festuca arundinacea schreb.) and prairie grass (bromus catharticus vhal) swards. tall fescue herbage mass and tiller density information was collected from an experiment where two nitrogen levels, two seeding arrangements and two grazing frequencies were evaluated. in prairie grass, the same information was obtained from swards managed with two levels of defoliation frequency and intensity. in tall fescue size density compensation mechanisms were observed when nitrogen nutrition limitation was overecome. prairie grass showed less phenotypic plasticity than tall fescue and density/compensation mechanisms were less evident.
Tillering dynamics of Tanzania guinea grass under nitrogen levels and plant densities
Braz, Thiago Gomes dos Santos;Fonseca, Dilermando Miranda da;Freitas, Fabrício Paiva de;Martuscello, Janaina Azevedo;Santos, Manoel Eduardo Rozalino;Santos, Márcia Vitória;
Acta Scientiarum. Animal Sciences , 2012, DOI: 10.4025/actascianimsci.v34i4.13382
Abstract: this study evaluated the influence of nitrogen levels (n) and plant density (d) on the tillering dynamics of tanzania guinea grass (panicum maximum jacq.). treatments were arranged in a completely randomized block design with 12 treatments and two replicates in a factorial scheme (4 × 3) with four levels of n (0, 80, 160 or 320 kg ha-1 n) and three plant densities (9, 25, and 49 plant m-2). higher number of tillers was observed in the treatment with 9 plants m-2 and under higher levels of n, especially in the second and third generations. still, the n influenced quadratically the appearance rate of basal and total tillers, which were also affected by plant density and interaction n × d. however, the appearance rate of aerial tiller was not influenced by factors evaluated. the mortality rate of total tiller was influenced quadratically by the nitrogen levels and plant densities. the mortality rate of basal tiller responded quadratically to plant density, whereas the mortality rate of aerial tiller increased linearly with fertilization. pastures with low or intermediate densities fertilized with nitrogen, presented a more intense pattern of tiller renewal.
Desempenho de bovinos em capim-tanzania adubado com nitrogênio ou consorciado com Estilosantes Performance of beef cattle grazing Tanzania grass fertilized with nitrogen or intercropped with Stylo  [cached]
Ossival Lolato Ribeiro,Ulysses Cecato,Bruno Shigueo Iwamoto,Alyson Pinheiro
Revista Brasileira de Saúde e Produ??o Animal , 2011,
Abstract: Com este estudo objetivou-se avaliar a massa seca de forragem e laminas foliares, ganho médio diário, taxa de lota o e ganho de peso vivo em capim-tanzania (Panicum maximum Jacq.) no período de novembro de 2008 a julho de 2009 sob lota o contínua. Utilizou-se delineamento experimental em blocos ao acaso em parcela subdivididas, com três repeti es, e como tratamentos: Tanzania + Estilosantes Campo Grande; Tanzania + 75kg/ha de N; Tanzania + 150kg/ha de N e Tanzania + 225kg/ha de N, e nas sub-parcelas os períodos do ano: primavera, ver o e outono. No ver o, a massa seca de forragem e laminas foliares foram superiores à primavera e outono. O tratamento com 225kg de N apresentou maior massa seca de forragem e massa seca de laminas foliares no ver o e outono. Obteve-se maior ganho médio diário no ver o. Na primavera e no ver o n o houve diferen a entre os tratamentos para o ganho médio diário, e no outono o tratamento com 225kg/ha de N foi superior. A taxa de lota o foi semelhante no ver o e outono, e menor na primavera. O tratamento com 225kg de N apresentou maior taxa de lota o na primavera e ver o. O tratamento com 225kg de N apresentou maior ganho de peso vivo no outono, na primavera e ver o o 150 kg de N foi semelhante. A disponibilidade de massa seca de forragem e o desempenho animal proporcionado pelo Estilosantes foram equivalentes à aduba o nitrogenada até a dose de 75kg de N. This study aimed to evaluate the dry mass of forage and leaf blade dry mass, average daily gain, stocking rate and live weight gain in Tanzania grass (Panicum maximum Jacq.) from November/2008 to July/2009, on continuous stocking. The experimental design was a split-plot arrangement in a randomized blocks design, with three replications and four treatments: Tanzania + Campo Grande Stylo; Tanzania + 75kg/ha of N; Tanzania + 150kg/ha of N and Tanzania + 225kg/ha of N, subplots were the seasons of the year: Spring, Summer and Autumn. The forage dry mass and leaf blade dry mass was higher in Summer compared to Spring and Autumn. The treatment with 225kg of N presented higher dry mass of forage and leaf blade dry mass in Summer and Autumn. It was obtained the higher average daily gain in the Summer. In the Spring and Summer no differences were observed for average daily gain, but in the Autumn the treatment with 225kg/ha of N was the best. The stocking rate was similar in Summer and Autumn, but lower in Spring. The treatment with 225kg of N presented the higher stocking rate in Spring and Summer. The treatment with 225kg of N presented the higher live weight gain in Autumn, w
Effects of growth habits of legumes on weed population in grass/legume mixed swards
Jolaosho,A.O.; Anele,U.Y.; Arigbede,O.M.; Olanite,J.A.; Onifade,O.S.;
Archivos de Zootecnia , 2009, DOI: 10.4321/S0004-05922009000100017
Abstract: grass-legume swards form the basis of many productive pasture systems. a study was carried out to evaluate their ability to smother weeds. a total of twelve treatments consisting of grass/ legume mixed swards were planted in july, 2004. soil analysis of the site was carried out prior to and after the study. some agronomic data like plant height, leaf number and population of weeds found in the plots were recorded using a meter square quadrat. there was a slight increase in the nitrogen content of the soil in 2005 after the study. the weed populations were highest during the first three weeks after planting. the weed population reduced drastically with increasing week. there were significant differences (p<0.05) in the population of the weeds in the mixed sward during the 2 year duration of this study. stylosanthes hamata recorded higher weed populations during the first year while a higher weeds population was recorded in the plots of tephrosia bracteolata during the second year.
Canopy characteristics, animal behavior and forage intake by goats grazing on Tanzania-grass pasture with different heights
Ribeiro, Aline Mendes;Oliveira, Maria Elizabete de;Silva, Patrícia Carvalho da;Rufino, Marcelo de Oliveira Alves;Rodrigues, Marc?nio Martins;Santos, Maurílio Souza dos;
Acta Scientiarum. Animal Sciences , 2012, DOI: 10.4025/actascianimsci.v34i4.14544
Abstract: this study evaluated the influence of tanzania-grass sward height (30, 50, 70 and 90 cm) on the morphological characteristics of the canopy, grazing behavior and forage intake by adult anglo nubian female goats. a completely randomized experimental design was employed, with two replicates in space and two replicates in time. six animals were used to assess the grazing behavior, and four, the ingestion process. the rise in sward height increased the forage and leaf mass, the percentages of stem and dead material, and reduced the leaf stem-1 ratio. above 50 cm there was an increase in grazing time and a decrease in leisure time. a positive linear correlation was detected between sward height and bite depth. the consumed forage mass, ingestion rate and daily intake were higher at 50 cm, indicating that the other heights reduced the intake process. the sward height was negatively correlated to the bite rate and positively to the bite time. the sward height of 50 cm presents the best combination of features, favoring the grazing and ingestive behavior of female adult goats.
Composi??o química de capim-tanzania adubado com nitrogênio e fósforo
Sousa, Ronaldo Silva;Pires, Aureliano José Vieira;Carvalho, Gleidson Giordano Pinto de;Silva, Fabiano Ferreira da;Magalh?es, Albertí Ferreira;Veloso, Cristina Mattos;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010000600006
Abstract: it was evaluated in this work the contents of dry matter (dm), crude protein (cp), neutral detergent fiber (ndf), total digestible nutrients (tdn), calcium (ca), phosphorus (p) and magnesium (mg) in the aerial section of the tanzania grass (panicum maximum), fertilized with nitrogen and phosphorus during the summer and autumn. the experimental design was complete randomized, with a 4 × 3 factorial scheme, and four n rates (0, 100, 200, and 300 kg/ha/year), and three pentoxide diphosphorus (p2o5) rates (0, 50, and 100 kg/ha/year), with three replicates. three cuts were made at 40 cm of the soil, every 35 days. after each cut, the fertilization was accomplished, and p2o5 was applied only once on the uniformed cut and n was parceled in three times. nitrogen rates did not affect contents of magnesium and they reduced contents of dry matter, calcium and phosphorus, while phosphate fertilization increased levels of phosphorus. fertilization had a quadratic effect on the levels of crude protein, neutral detergent fiber, and total digestible nutrients providing a forage of better quality as doses increased, mainly nitrogen doses. in the studied edaphoclimathic conditions, it is recommend fertilization of tanzania grass with 300 kg of n/ha and 100 kg of p2o5/ha.
Evaluation of the grass-tanzania ("Panicum maximum") using multivariate analyses Avalia o do capim-tanzania ("Panicum maximum") por meio de métodos de análise multivariada
Anderson de Moura Zanine,Paulo Francisco Dias,Sebasti?o Manh?es Souto,Daniele de Jesus Ferreira
Revista Brasileira de Saúde e Produ??o Animal , 2008,
Abstract: The experiment was conducted with objective of evaluating the tanzania grass, using mult-trait procedures: discriminant function analysis and principal components analysis. The variables were: dry matter of leaf (DML), dry matter of the plant (DMP), nitrogen (N), phosphorous (P), magnesium (Mg), calcium (Ca) and potassium (K) in the aerial part and in the root of the grass, during the rain period. The plants were fertilized with four doses of N as bovine manure (0, 60, 120, 180 kg/ha). Main components analysis was capable to reduce the 15 original variables to 6 principal components, which the most important variables were calcium at root, potassium at leaf, potassium at plant, magnesium at leaf, phosphorous at leaf and phosphorous at root. The discriminant analysis had difficulties in classifying the fertilizer dose, especially related to the levels 60, 120 e 180 kg/ha. Foi realizado um experimento com objetivo de avaliar o capim-tanzania, por meio da técnica de análise multivariada: análise discriminante e análise de componentes principais. As variáveis avaliadas foram: matéria seca foliar (MSF), matéria seca da planta (MSP), nitrogênio (N), fósforo (P), magnésio (Mg) e cálcio (Ca) na parte aérea e na raiz, da gramínea, realizados no período das chuvas (primavera/ver o). As plantas foram adubadas com quatro doses de N na forma de chorume bovino (0, 60, 120, 180 kg/ha). A análise de componentes principais foi capaz de reduzir o número de variáveis originais de 15 para seis componentes principais, sendo que as variáveis mais importantes foram cálcio na raiz (CaR), potássio na folha (KF), potássio na planta (KP), magnésio na folha (MgF), fósforo na folha (PF) e fósforo na raiz (PR). A análise discriminante encontrou dificuldades em classificar quanto à dose de adubo, principalmente em rela o às doses 60, 120 e 180 kg/ha.
Morphogenetic characteristics and management of Tanzania grass
Santos, Patricia Menezes;Balsalobre, Marco Ant?nio Alvares;Corsi, Moacyr;
Pesquisa Agropecuária Brasileira , 2003, DOI: 10.1590/S0100-204X2003000800012
Abstract: the objective of this work was to evaluate the effect of grazing interval and period of evaluation over tissue turnover in tanzania grass pastures (panicum maximum cv. tanzania) and to ascertain if herbage accumulation rate can be used as a criterion to establish a defoliation schedule for this grass in southeast of brazil. a randomized block design with a split-plot arrangement was used. the effect of three grazing intervals was evaluated within seven periods between october 1995 and september 1996. responses monitored were leaf and stem elongation rates, leaf senescence rate, stem length, and tiller density. net herbage accumulation rate was calculated using tissue turnover data. the grazing intervals for tanzania grass should be around 38 days between october and april (spring and early autumn) and 28 days during the reproductive phase of the grass (april/may). between may and september (late autumn and winter), grazing interval should be around 48 days. herbage accumulation rate is not a good criterion to establish defoliation time for tanzania grass. studies on the effects of stem production in grazing efficiency, animal intake and forage quality are needed to improve tanzania grass management.
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