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Somatic embryogenesis in Lolium multiflorum suspension culture
Margarita Pavlova,Elizabeth Kordyum
Acta Societatis Botanicorum Poloniae , 1996, DOI: 10.5586/asbp.1996.007
Abstract: The embryogenic cell suspension was obtained from immature embryos of Lolium multiflorum through a callus culture. Somatic embryogenesis was induced by addition of 2,4-D, dicamba and picloram in 0,5 mg/l concentrations in MS liquid nutrient medium. It was shown that somatic embryos arised from single cells. In globular embryoids, the meristematic cells are characterized by the presence of phytoferritin inclusions in the leucoplasts.
Morphology and pollen viability of Lolium multiflorum Lam.
Nunes, Renata de Castro;Bustamante, Fernanda de Oliveira;Techio, Vania Helena;Mittelmann, Andréa;
Ciência e Agrotecnologia , 2012, DOI: 10.1590/S1413-70542012000200006
Abstract: study and characterization of pollen grains are essential for different areas, especially taxonomy, genetic improvement, phylogeny, and paleobotany. as yet, there are no reports on pollen morphology of genotypes of naturalized lolium multiflorum lam., introduced cultivars or breeding populations, diploid or polyploid. ten genotypes of annual ryegrass (l. multiflorum) were evaluated for the viability of pollen grains using propionic carmine and alexander's stains, while morphology was assessed by the acetolysis technique. measures of polar axis (p), equatorial diameter (e), exine thickness, and analysis of pollen grains were obtained by scanning electron microscopy (sem). all genotypes showed high rate of pollen viability (> 89%) for both stains. there were differences between genotypes in the following quantitative traits: polar axis, equatorial diameter, exine, endexine, ektexine, and p/e ratio. pollen grains were characterized as small, monoporates, with circular and non-prominent apertures. in addition to helping distinction of pollen grains, morphometric differences can be used later to compare ploidy levels, thus assisting in breeding programs of the species.
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.
Análisis de la sensibilidad de biotipos de Lolium multiflorum a herbicidas inhibidores de la enzima ALS, ACCasa y Glifosato Sensitivity analysis of Lolium multiflorum biotypes to Glyphosate, ACCase and ALS-inhibiting herbicides
P. Diez De Ulzurrun,M.I. Leaden
Planta Daninha , 2012, DOI: 10.1590/s0100-83582012000300024
Abstract: A pesar de los avances logrados en el control de las malezas con el uso de herbicidas, el manejo de las mismas no se simplificó, sino que, al contrario, surgieron nuevos desafíos, como la aparición de resistencia a herbicidas. En 2007, se reportó en Lolium multiflorum el segundo caso de resistencia a glifosato detectado en Argentina. En el sudeste de la provincia de Buenos Aires se registraron fallas de control a campo en poblaciones de Lolium multiflorum debido a su resistencia a distintos herbicidas de las familias de los inhibidores de ALS y de ACCasa y al herbicida glifosato. El objetivo de este estudio fue caracterizar el nivel de resistencia a ciertos herbicidas inhibidores de la ALS y de la ACCasa y al glifosato en una población de L. multiflorum de Lobería (Bs As, Argentina) supuestamente resistente (LmR). Se realizaron bioensayos en cajas de Petri y se determinó la GR50 mediante la variación en la longitud de coleoptile. Las curvas de dosis-respuesta se obtuvieron por medio de la ecuación log-logística. El biotipo LmR presentó resistencia múltiple a herbicidas con tres modos de acción diferentes: glifosato, inhibidores de ALS y de ACCasa. Dicho ensayo demostró la aparición de un biotipo de L. multiflorum con resistencia a múltiples principios activos. Despite progress in weed control using herbicides, management has not been simplified, but new challenges such as herbicides resistance have arisen. In 2007, a Lolium multiflorum population resistant to glyphosate was reported, as the second case of glyphosate resistant weeds in Argentina. In the southeast of Buenos Aires province, control failures in populations of L. multiflorum to different families of herbicide such as ALS and ACCase inhibitors and to glyphosate at field level have been registered. The aim of this study was to characterize the level of resistance to certain herbicides inhibitors of ALS, ACCase and glyphosate in a putatively resistant (LmR) population of L. multiflorum of Loberia (Buenos Aires, Argentina). Bioassays were conducted in Petri dishes and the GR50 was determined by the length of coleoptile. Curves dose-response were obtained using the log-logistic equation. The LmR biotype survived under multiple herbicides of three different modes of action, glyphosate, ALS and ACCase inhibitors. This test showed the appearance of a biotype of L. multiflorum with resistance to multiple active ingredients.
The effect of different condensed phosphates on the yield of Lolium multiflorum and their effect on different interrelations  [cached]
Leonida CALANCEA
Notulae Botanicae Horti Agrobotanici Cluj-Napoca , 1978,
Abstract: The condensed phosphates such as ammonium pyrophosphate, potassium, metaphosphate, ammonium polyphosphates are among the newest achievements in the domain of fertilizers (5, 6). Results of various experiments have shown that these fertilizers increase the yield in wheat, barley, maise, potato, sugar beat, bean and others (2, 3, 5). However, experiments in this field are few (3). In Lolium multiflorum the reactions of these forms of phosphorus were not illustrated in many cases, because the experiments had been carried out with salts of NH4, K and Ca, where the effect was combined. The objective of this report is to present results of a series of greenhouse pot experiments.
Litter Decomposition of Acacia caven (Molina) Molina and Lolium multiflorum Lam. in Mediterranean Climate Ecosystems
Martínez G,Ingrid; Zagal V,Erick; Ovalle M,Carlos; Co?teaux,Marie-Madeleine; Stolpe,Neal B; Valderrama V,Natalia;
Chilean journal of agricultural research , 2010, DOI: 10.4067/S0718-58392010000300013
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.
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
Effect of organic contaminants on seed germination of Lolium multiflorum in soil  [PDF]
DL Korade,MH Fulekar
Biology and Medicine , 2009,
Abstract: The seed germination trials have relevance in selection of the plants for their prospective use inphytoremediation. The effect of organic contaminants; anthracene and chlorpyrifos on the seedgermination of Lolium multiflorum (ryegrass) has been investigated. The germination of ryegrass seedswas evaluated in the separately spiked soil with organic compounds at the concentrations 10, 25, 50, 75and 100 mg/kg while un-spiked soil taken as control. There was no inhibitory effect of anthraceneobserved on germination as compared to the control whereas significant reduction and delay in seedgermination was observed at the higher chlorpyrifos concentrations of 75 and 100 mg/kg. The resultsshow the pesticide (chlorpyrifos) toxicity was not caused to the ryegrass seeds up to the concentrationof 50 mg/kg. The level of seed germination was found to decrease with increasing concentrations ofchlorpyrifos in the soil. The findings of this study assessed ability of ryegrass seeds to survive andtolerate the contaminants for phytoremediation studies.
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
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.
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