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Steers performance grazing ryegrass (Lolium Multiflorum) with or without energetic supplementation / Desempenho de bovinos de corte em pastagem de azevém (Lolium Multiflorum) com ou sem suplementa o energética  [cached]
Christopher Hellbrugge,Fernanda Barros Moreira,Ivone Yurika Mizubuti,Ivanor Nunes do Prado
Semina : Ciências Agrárias , 2008,
Abstract: The objective of this work was to evaluate the performance of steers grazing ryegrass pasture (Lolium multiflorum), with or without energetic supplementation (cracked corn) and to evaluate the economic return of this supplementation. Twenty two Simental steers with initial body weight (IBW) of 394.8 kg were used. Two ryegrass (Lolium multiflorum) padocks were used, with a stocking rate of 1.36 AU/ha. The energetic supplement was 100% of cracked corn. The average daily gain (ADG) for supplemented steers was higher (1.68 kg/day) than ADG of no supplemented steers (1.36 kg/day). One kg of carcass was obtained for each 5,55kg of supplement. The energetic supplementation was viable when the price of each 15 kg of carcass was R$ 53.00 and when the price of the energetic supplement (corn) was R$ 250.00/ton. O objetivo deste trabalho foi avaliar o desempenho de novilhos de corte sob pastejo em azevém (Lolium multiflorum) com ou sem suplementa o energética (milho triturado) e analisar a viabilidade econ mica dessa suplementa o. Foram utilizados machos n o-castrados Simental PO, com idade média de 22 meses e peso inicial médio de 394,8 kg. Foram utilizados dois piquetes de azevém, com taxa de lota o de 1,36 UA/ha. O suplemento energético era composto por 100% de milho triturado. O ganho médio diário (GMD) para os novilhos suplementados foi superior (1,68 kg/dia) ao GMD dos novilhos n o suplementados (1,36 kg/dia). Obteve-se um kg de carca a para cada 5,55 kg de suplemento utilizado. A suplementa o energética foi viável para a cota o da arroba à R$ 53,00 e do suplemento energético (milho) à R$ 250,00/tonelada.
Resistência de azevém (Lolium multiflorum) ao herbicida glyphosate
Roman, E.S.;Vargas, L.;Rizzardi, M.A.;Mattei, R.W.;
Planta Daninha , 2004, DOI: 10.1590/S0100-83582004000200018
Abstract: italian ryegrass (lolium multiflorum) is cultivated as forage and/or cover crop in no-till system. however, it is also a serious weed in wheat and other winter cereals in southern brazil. experiments were conducted at greenhouse and field conditions to evaluate the susceptibility of two ryegrass biotype to glyphosate as well as the efficacy of other herbicides on the post-emergence control of the species for sowing wheat under no-till system. the experimental design was a completely randomized design for the greenhouse experiment and a completely randomized block design for the field experiment. herbicides with different mechanisms of action were evaluated on the weed control: glyphosate, glufosinate, clethodim, haloxyfop-r and diclofop, paraquat and paraquat+diuron. the results obtained under greenhouse conditions indicated the glyphosate susceptible biotype was controlled by the rate of 360 g e.a. ha-1. the resistant ryegrass biotype had no reduction in dry matter production and less than 15 % phytotoxicity caused by glyphosate up to 1,440 g e.a. ha-1. however, glyphosate rates between 1440 and 5,760 g e.a. ha-1 reduced dry matter accumulation and resulted in toxicities under45%. under field conditions, the best lolium multiflorum control was given by clethodim 79.2 g ha-1 and diuron + paraquat at 300+600 g ha1, respectively. the results obtained in these studies indicated that the population was composed predominantly by a biotype resistant to epsps inhibitor herbicides.
Competi o de azevém (Lolium multiflorum L. ) com duas cultivares de trigo Ryegrass (Lolium multiflorum L. ) competition with two wheat cultivars
N.G. Fleck
Planta Daninha , 1980, DOI: 10.1590/s0100-83581980000200001
Abstract: Com os objetivos de avaliar a habilidade de duas cultivares de trigo em competir com azevém (Lolium multiflorum, L.) e de estimar os efeitos da concorrência de várias densidades desta espécie sobre a cultura, foi conduzido experimento a campo durante a esta o de crescimento de 1978, na Esta o Experimental Agron mica da UFRGS, em Guaíba, RS. Foram comparadas as cultivares de trigo 'E-7414' e 'PAT-7219', na popula o de 300 plantas por m', com azevém semeado nas densidades de 0, 2,5, 5,0, 10,0 e 20,0 kg/ha, as quais originaram popula es médias de 0, 130, 210, 470 e 750 plantas por m2 , respectivamente. A competi o entre as espécies foi mantida durante o ciclo da cultura. Para o rendimento de gr os da cultivar 'E-7414', a competi o exercida pelo azevém ocasionou decréscimos variáveis entre 18% e 56%, dependendo da infesta o; enquanto para a cultivar 'PAT-7219', as redu es no rendimento de gr os se situaram entre 4c é 22%, conforme a densidade do azevém. Enquanto para 'PAT-7219' n o foram significativas as redu es no rendimento de gr os, para `E-7414' os decréscimos verificados alcan aram significancia estatística. A análise do peso da matéria seca do azevém demonstrou que este aumentou proporcionalmente ao aumento de sua popula o, mas que aquela variável foi significativamente menor quando o azevém esteve competindo com 'PAT-7219' do que com `E-7414'. Em média, diminuiu em 31% a matéria seca do azevém produzida sob 'PAT-7219' em rela o à `E-7414'. A field experiment was conducted to evaluate the ability of two wheat cultivars to compete with ryegrass (Lolium multiflorum L.), and to estimate the competition effects of various densities of this species on the crop, at the Agronomy Experimental Station, in Guaiba, RS, during the 1978 wheat growing season. Two wheat cultivars ('E-7414' and 'PAT-7219') were grown in competition with ryegrass at the densities of 0, 130, 210, 470, and 750 plants per m'. The competition effects were maintained during the whole wheat cycle. Depending on the weed population, ryegrass competition caused significant decreases, varying from 18 to 56%, in seed yield of the wheat cultivar `E-7414'; whereas, for `PAT-7219' cultivar, although seed yield reductions varied from 4 to 22% , were not statistically significant. Ryegrass dry matter production increased proportionally to its population. However, ryegrass dry matter yield was significantly lower whe n this specie s competed with 'PAT-7219' wheat cultivar than with 'E-7414'. As an average for the established densities, ryegrass dry matter produced in competi tion with 'PAT
Controle químico de azevém (Lolium multiflorum L.) na cultura do trigo Chemical control of ryegrass (Lolium multiflorum L.) in wheat
N.G. Fleck,R.J. Paulitsch
Planta Daninha , 1978,
Abstract: Em trabalho experimental a campo realizado em 1977 na regi o da Depress o Central do Rio Grande do Sul, avaliaram-se tratamentos herbicidas destinados a controlar seletivamente azevém (Lolium multiflorium L.) e trigo (linhagem E-7414); bem como também se objetivou estabelecer os níveis de competi o recíproca entre ambas as gramíneas. Foram comparados no experimento os herbicidas cianazina, clorobromuron, clorotoluron, diclofop, diuron, metoxuron e terbutrina com os tratamentos testemunhas: trigo sem azevém, trigo com azevém e azevém sem trigo. Todos os herbicidas foram aplicados em pós-emergência, quando o trigo se apresentava no estádio de 3-4 folhas, e o azevém se encontrava no estádio e 1-3 folhas. Verificou-se que a infesta o de azevém quando n o foi controlada de nenhum modo, ocasionou uma redu o média de 52% no rendimento de gr os de trigo. Por outro lado, constatou-se que a popula o de trigo, ao exercer competi o sobre as plantas de azevém, causou uma diminui o da ordem de 42% em sua matéria seca. Observou-se que todos os herbicidas demonstraram fitotoxicidade, havendo causado desde danos leves até muito severos às plantas de trigo, dependendo do produto utilizado; e, que os rendimentos de gr os obtidos dos tratamentos herbicidas foram inferiores ao da testemunha livre de azevém. No entanto, todos os compostos químicos testados apresentaram significativa atividade de pós-emergência, demonstrando potencial de controle ao azevém. Tanto a obten o da matéria seca do azevém, como a avalia o visual do seu controle demonstraram ser métodos apropriados para medir o efeito herbicida. Dentre os herbicidas avaliados, o diclofop foi o tratamento que propiciou controle mais eficiente ao azevém, menor grau de fitotoxicidade e mais elevado rendimento de trigo; de um modo geral, seguiu-se-lhes nestas características o clorotoluron. Os herbicidas clorobromuron e metoxuron, embora demonstrassem relativa seletividade ao trigo, exerceram inadequada atividade de pós-emergência sobre o azevém. O tratamento diuron mostrou comportamento insuficiente tanto em rela o ao controle do azevém, quanto ao rendimento do trigo. Os herbicidas cianazina e terbutrina proporcionaram adequado controle do azevém; contudo, suas seletividades à cultura do trigo foram muito reduzidas, além de terem causado diminui o no poder germinativo das sementes de trigo colhidas das parcelas tratadas com estes herbicidas. A field experiment was conducted during 1977 in the Central Depression region of Rio Grande do Sul to evaluate herbicide treatments to selectively control ryegrass (Lolium
Litter Decomposition of Acacia caven (Molina) Molina and Lolium multiflorum Lam. in Mediterranean Climate Ecosystems Descomposición de Hojarascas de Acacia caven (Molina) Molina y Lolium multiflorum Lam. en Ecosistemas de Clima Mediterráneo  [cached]
Ingrid Martínez G,Erick Zagal V,Carlos Ovalle M,Marie-Madeleine Co?teaux
Chilean Journal of Agricultural Research , 2010,
Abstract: The ecosystems of the Mediterranean interior dryland of Chile, dominated by an espinal agroecosystem of Acacia caven (Molina) Molina, show low productivity as a result of soil degradation. The objective of this study was to evaluate litter decomposition of A. caven and Lolium multiflorum Lam. in espinal ecosystems: well preserved (Wp) 50 to 80%, typical (Pd) 25 to 50%, and degraded (De) with 10 to 25% cover. During 420 d and starting in April 2004 until August 2005, weight loss in litter bags and chemical composition (hemicellulose, cellulose, lignin, non-structural components, ash, N, C, C/N ratio, and P) were determined by using near infrared reflectance spectroscopy (NIRS) and the Van Soest protocol. Weight loss ranged from 31 to 52% in L. multiflorum and 26 to 40% in A. caven after 420 d. During the chemical decomposition process of L. multiflorum, cellulose degradation was relevant in the labile phase while lignin was important in the recalcitrant phase. On the other hand, non-structural components and cellulose were degraded in the labile phase and lignin in the recalcitrant stage for A. caven. Moreover, both litters improved N concentration during the decomposition process. Espinal ecosystems with higher canopy cover (Pd and Wp) had a positive influence, and showed early effects during the decomposition process, especially in the De espinal ecosystem, probably because of the microenvironmental conditions it generated. A better knowledge of the dynamics of litter decomposition in ecosystems was achieved by using both techniques: litter bags and NIRS. Los ecosistemas del secano interior mediterráneo de Chile presentan una baja productividad debido a la degradación de los suelos, dominados por un agroecosistema espinal de Acacia caven (Molina) Molina. El objetivo de este estudio fue evaluar la descomposición de hojarascas de A. caven y Lolium multiflorum Lam., en ecosistemas espinales: densos (Wp) con cobertura de 50-80%, poco densos (Pd) 25-50% y degradados (De) 10-25%. Se determinó la pérdida de peso usando bolsas de malla, durante 420 días comenzando en abril de 2004, y la composición química del material: hemicelulosa, celulosa, lignina, componentes no estructurales, cenizas, N, C, relación C/N y P; usando espectroscopía de reflectancia en el infrarrojo cercano (NIRS). Los resultados indicaron que la pérdida de peso fue mayor en L. multiflorum (31-52%) que en A. caven (26-40%). La descomposición del material estuvo influenciada por su composición química, en L. multiflorum gobernada en su fase lábil por la degradación de celulosa y en su fase re
Avalia o da mistura de cultivares de aveia preta (Avena strigosa Schreb) com azevém (Lolium multiflorum Lam.) sob pastejo  [cached]
Macari Stefani,Rocha Marta Gomes da,Restle Jo?o,Pilau Alcides
Ciência Rural , 2006,
Abstract: O experimento foi conduzido com objetivo de avaliar a produ o de novilhas de corte em duas cultivares de aveia preta (Avena strigosa Schreb): "Comum" e "IAPAR 61" em mistura com azevém (Lolium multiflorum Lam.). Foram avaliadas a massa de forragem (MF), oferta de forragem (OF), taxa de acúmulo diário de matéria seca (TA), carga animal (CA), ganho médio diário (GMD), ganho de peso vivo por hectare (GPA), proteína bruta (PB) e digestibilidade in vitro da matéria organica (DIVMO). As cultivares avaliadas n o diferiram (P>0,05) para TA, CA, GMD, GPA e PB. A DIVMO de IAPAR 61 manteve valores mais elevados durante um período mais prolongado da esta o de crescimento da pastagem. A cultivar de aveia preta IAPAR 61 pode ser indicada para utiliza o sob pastejo no Estado do Rio Grande do Sul.
Desempenho de ovinos recebendo suplementos ou mantidos exclusivamente em pastagem de azevém (Lolium multiflorum Lam.)
Farinatti, Luís Henrique Ebling;Rocha, Marta Gomes da;Poli, César Henrique Espírito Candal;Pires, Cléber Cassol;P?tter, Luciana;Silva, José Henrique Sousa da;
Revista Brasileira de Zootecnia , 2006, DOI: 10.1590/S1516-35982006000200027
Abstract: the objective of this trial was to evaluate production of nursing ewes and yearling female lambs grazing annual ryegrass pasture (lolium multiflorum lam) supplemented or not with corn grain or soybean meal. supplements were fed to animals in a quantity equivalent to 1% of sheep unit (ewe + lamb) body weight. the following variables were investigated: average daily gain, body weight gain per hectare, and stocking rate while for ryegrass pasture the following measurements were taken: forage mass, losses, and allowance, pasture height, green leaf allowance, forage mass accumulation rate, total forage production, crude protein content, and in vitro digestibility of hand plucking material. supplementation did not significantly affect the stocking rate in this trial. female lambs supplemented with soybean meal had higher average daily gain than those not supplemented that lost 3.4 g daily on pasture only. body weight gain per hectare was highest by feeding soybean meal to sheep. the sward structure changed during pasture cycle independently of treatment effects.
Anatomia foliar de Lolium multiflorum sensível e resistente ao glyphosate
Galvani, J.;Rizzardi, M.A.;Carneiro, C.M.;Bianchi, M.A;
Planta Daninha , 2012, DOI: 10.1590/S0100-83582012000200021
Abstract: this work aimed to contribute to the anatomical knowledge of the species lolium multiflorum and to observe possible changes that may elucidate the mechanism that confers its resistance to the herbicide glyphosate. thus, an experiment was conducted using four biotypes of this species with distinct sensitivities to the herbicide glyphosate: one susceptible (b1s) and three resistant biotypes (b2r, b3r and b4r). analyses were conducted on the transverse and longitudinal sections of the vegetative organs of the plants at the tillering stage. anatomically, ryegrass is characterized as having a large number of stomata and buliform cells as well as homogeneous mesophylls constituted only of palisade cells compactly distributed. comparatively, no evident morphological differences occur that can be used to distinguish sensitive from resistant biotypes; however, the resistant biotypes, especially b3r b4r, presented higher stomatal density, compared to the others. still, the resistant biotypes had a higher amount of intercellular spaces in the mesophyll and vascular bundles with a smaller amount of phloem compared to the xylem, which, because of their functions in the plants, may contribute to the lower sensitivity to the herbicide.
EFECTO DE AVENILLA (Avena fatua L.) Y BALLICA (Lolium multiflorum Lam.) EN EL RENDIMIENTO DE TRIGO EN DOS áREAS AGROECOLóGICAS Wild oat (Avena fatua L.) and italian ryegrass (Lolium multiflorum Lam.) effect on wheat yield at two locations  [cached]
Alberto Pedreros L.
Agricultura Técnica , 2001,
Abstract: Se efectuaron dos ensayos de campo, mediante un dise o aditivo, para evaluar el efecto de densidades crecientes de avenilla (Avena fatua L.) y ballica (Lolium multiflorum Lam.), separadamente, en la producción de trigo (Triticum aestivum L.) primaveral e invernal en el valle regado y la precordillera de uble, respectivamente. Las densidades de avenilla fluctuaron entre 0 y 16 plantas m-2 en la precordillera andina y entre 0 y 24 plantas m-2 en el valle regado. En ballica, se utilizaron densidades de 0 a 50 plantas m-2 en la precordillera andina y de 0 a 80 plantas m-2 en el valle regado. Los datos obtenidos se ajustaron a un modelo hiperbólico para predecir el rendimiento y pérdida en rendimiento. Aumentos de una planta de avenilla m-2 significaron, aproximadamente, una pérdida de 100 kg ha-1 de trigo; mientras que cada 10 plantas de ballicas m-2, significaron una pérdida de entre 140 y 200 kg ha-1 de trigo. Densidades de 3 avenillas m-2 proyectaron una pérdida en el rendimiento de trigo de 4,5% en el valle regado y de 3,5% en la precordillera, respectivamente. Densidades de 10 plantas de ballica m-2 predijeron una pérdida en el rendimiento de trigo de 1,6% en el valle regado y de 1,3% en la precordillera. Con las pérdidas proyectadas por el modelo hiperbólico, el umbral económico varió entre 3 y 4,4 plantas de avenilla m-2 y 27 y 36 plantas de ballica m-2, dependiendo del área agroecológica y del costo del control. Hubo una respuesta lineal a la densidad de cada maleza para producir semillas por plantas no controladas en el cultivo de trigo. La mayor densidad de avenilla, 24 plantas m-2, incrementó el reservorio en el suelo en casi 2000 semillas m-2, mientras que la mayor densidad de ballica, 80 plantas m-2, lo hizo en más de 28.000 semillas m-2. Two experiments were conducted, through additive design, to evaluate the effect of increasing densities of wild oats (Avena fatua) and Italian ryegrass (Lolium multiflorum), separately, on winter and spring production of wheat (Triticum aestivum L.) at two locations in Chile. Wild oat densities between 0 to 16 plants m-2 in the Andean foothills, and 0 to 24 plants m-2 in the irrigated valley, and Italian ryegrass densities between 0 to 50 plants m-2 in the Andean foothills, and 0 to 80 plants m-2 the irrigated valley were used. A hyperbolic model was fitted to the data to predict wheat yield and loss. Every additional wild oat plant m-2 reduced wheat yield by approximately 100 kg ha-1, while every additional 10 Italian ryegrass plants m-2 reduced wheat yield about 140 to 200 kg ha-1. Wild oat densities of 3 p
Transloca??o do glyphosate em biótipos de azevém (Lolium multiflorum)
Ferreira, E.A.;Santos, J.B.;Silva, A.A.;Oliveira, J.A.;Vargas, L.;
Planta Daninha , 2006, DOI: 10.1590/S0100-83582006000200021
Abstract: this work evaluated foliar absorption and glyphosate translocation in italian ryegrass (lolium multiflorum) susceptible and resistant biotypes, 14c-glyphosate was applied by using a precision micro syringe, and adding 10 μl of solution on the adaxial side of the first leaf with ligule totally visible, when italian ryegrass plants showed 3 tillers. the quantity of glyphosate absorbed and translocated was evaluated through a liquid scintilation spectrometer by measuring radiation emitted by 14c-glyphosate at 2, 4, 8, 16, 32 and 64 hours after application. the roots and aerial part were analyzed as well as the leaf where application was performed and the solution used to wash the leaf. glyphosate absorption speed was similar in both italian ryegrass biotypes, with over 50% of herbicide absorption in the first 8 hours after application. up to 64 hours, higher retention (81.64%)of glyphosate was observed in the resistant biotype, while only 55% was retained in the susceptible biotype. in the remaining aerial part and roots, a higher amount of glyphosate was absorbed by the susceptible biotype, indicating higher capacity of its translocation. after 64 hours of application, only 6%, of glyphosate was found in the plants, on average indicating that most of the product could be exuded. it could be concluded that italian ryegrass sensitivity to glyphosate can be attributed to higher translocation capacity of this herbicide by susceptible biotypes.
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