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Saponins and Sapogenins from Brachiaria decumbens Stapf
Pires, Viviane S.;Taketa, Alexandre T. C.;Gosmann, Grace;Schenkel, Eloir P.;
Journal of the Brazilian Chemical Society , 2002, DOI: 10.1590/S0103-50532002000200002
Abstract: four steroidal saponins and three sapogenins were identified from aerial parts of brachiaria decumbens. their structures were established by chemical and spectroscopic means (1h and 13c nmr, hmbc, hmqc) as 3b-methoxy-lanost-9(11)-ene (1), diosgenin (2a), yamogenin (2b), 3-o-b-d-glucopyranosyl-24(s)-ethyl-22e -dihydrocholesterol (3a), 3-o-b-d-glucopyranosyl-24(r)-ethyl-22e -dihydrocholesterol (3b), dioscin (4a) and 3-o-{a-l-rhamnopyranosyl-(1?4)-[a-l-rhamnopyranosyl-(1 ?2)]-b-d-glucopyranosyl}-25(s)-spirost-5-en-3 b-ol (4b). all these compounds were isolated for the first time from b. decumbens and compound 4b is described for the first time as far as we know.
Saponins and Sapogenins from Brachiaria decumbens Stapf  [cached]
Pires Viviane S.,Taketa Alexandre T. C.,Gosmann Grace,Schenkel Eloir P.
Journal of the Brazilian Chemical Society , 2002,
Abstract: Four steroidal saponins and three sapogenins were identified from aerial parts of Brachiaria decumbens. Their structures were established by chemical and spectroscopic means (1H and 13C NMR, HMBC, HMQC) as 3beta-methoxy-lanost-9(11)-ene (1), diosgenin (2a), yamogenin (2b), 3-O-beta-D-glucopyranosyl-24(S)-ethyl-22E -dihydrocholesterol (3a), 3-O-beta-D-glucopyranosyl-24(R)-ethyl-22E -dihydrocholesterol (3b), dioscin (4a) and 3-O-{alpha-L-rhamnopyranosyl-(1->4)-[alpha-L-rhamnopyranosyl-(1 ->2)]-beta-D-glucopyranosyl}-25(S)-spirost-5-en-3 beta-ol (4b). All these compounds were isolated for the first time from B. decumbens and compound 4b is described for the first time as far as we know.
Estimativa da área foliar de plantas daninhas: Brachiaria decumbens Stapf. e Brachiaria brizantha (Hochst.) Stapf
Bianco, Silvano;Brendolan, Rodrigo A.;Alves, Pedro L. da C. A.;Pitelli, Robinson A.;
Planta Daninha , 2000, DOI: 10.1590/S0100-83582000000100008
Abstract: in order to obtain equations which make feasible the leaf area estiomate from linear measures of the leaf blade, correlation studies were done involving the real leaf blade area and main vein leaf lenght (c), maximum leaf width (l) and c*l. all the equations, linear, geometric and exponential, provide good leaf area estimate for both species. in the practical sense, it is suggested the use of the simple linear equation of the regression model using the c*l parameter and taking the linear coefficient equal zero. then, the brachiaria decumbens leaf area can be estimate using the equation sf = 0,9810 (c*l) and the brachiaria brizantha by using the equation sf = 0,7468*(c*l).
Produ??o e perfilhamento de Brachiaria decumbens Stapf. em fun??o de doses de enxofre
Santos, Anacleto Ranulfo dos;Monteiro, Francisco Antonio;
Scientia Agricola , 1999, DOI: 10.1590/S0103-90161999000300025
Abstract: an experiment with brachiaria decumbens stapf. cv. basilisk in a sand subtrate was carried out under greenhouse conditions from october to december 1996. the objective was to determine the effect of sulfur fertilization (eight sulfur levels were used: 0; 2; 4; 16; 32; 48; 64 and 80 mg l-1 of solution) on the forage dry weight and tiller number. a randomized complete block design, with four replications, was used. at forty and seventy days after transplanting, the first and second harvest were performed. sulfur rates significantly increased grass shoot and root dry weight and influenced the tiller number in the plants.
Meiotic arrest compromises pollen fertility in an interspecific hybrid between Brachiaria ruziziensis x Brachiaria decumbens (Poaceae: paniceae)
Mendes-Bonato, Andréa Beatriz;Pagliarini, Maria Suely;Valle, Cacilda Borges do;
Brazilian Archives of Biology and Technology , 2007, DOI: 10.1590/S1516-89132007000500011
Abstract: microsporogenesis was analyzed in an interspecific hybrid between an artificially tetraploidized sexual accession of brachiaria ruziziensis (2n=4x=36) and a natural apomictic tetraploid accession of b. decumbens. syncytes involving a large number of cells were recorded in 15.4% of meiocytes. meiosis progressed normally in syncytes during prophase i; in metaphase i, however, several nuclei were found fusioned, showing chromosome stickiness and several chromosome fragments. meiosis was arrested in metaphase i and pycnotic nuclei and micronuclei were formed. abnormal cytokinesis fractionated the syncyte into abnormal meiotic products that were covered by the pollen wall. meiocytes in leptotene were recorded in all the slides prepared for both meiotic divisions, and abnormal "pollen grains" with well-developed pollen wall but containing leptotene nuclei were recorded in 9.18% of grains analyzed. these findings suggested that the meiocytes received the signal to enter meiosis but lacked the signal to proceed beyond leptotene. despite the absence of the meiotic process, such cells were covered by pollen grain wall. total pollen sterility resulted from these abnormalities combined with still others observed among meiocytes.
CRECIMIENTO DE Brachiaria decumbens Stapf Y Cynodon nlemfuensis Vanderyst EN SUELOS SULFATADOS áCIDOS DE CóRDOBA
Combatt C,Enrique; Jarma O,Alfredo; Maza A,Libardo;
Revista MVZ Córdoba , 2008,
Abstract: objective. to assess the effect of different doses of lime in acid sulphate soils and physiological responses of two species of grasses, cynodon nlemfuensis vanderyst and brachiaria decumbens stapf. materials and methods. the work was carried out during 2006 in acid sulfate soils at el deseo farm (ciénaga de oro - córdoba, colombia), where 3, 6 and 9 tons/ha of agricultural lime was applied and two grass species, cynodon nlemfuensis vanderyst (pasto estrella) and brachiaria decumbens stapf (pasto brachiaria) were planted. the responses considered during 5 mowings were the chemical features of the soil, fresh and dry weight of each genotype and the leaf/stem ratio. an experiment of complete random blocks was designed using a structure of divided plots, where the main plots corresponded to the grasses and the subplots to the lime doses. results. the most outstanding results suggested that the ph values and aluminum in the soil concentrations fall significantly with the quantity of applied lime, decreasing up to 80%. in general, the interchangeable bases increased with the lime dosage and the contents of the microelements decreased considerably over time, although this was not evident for the lime. independently of genotype, the production of fresh biomass showed a linear relationship within lime dosage (y=0,656x + 11,99; r2=0.92); the dry mass and the leaf/stem ratio were always greater for b. decumbens compared to c. nlemfuensis, independent of lime dosage.
CRECIMIENTO DE Brachiaria decumbens Stapf Y Cynodon nlemfuensis Vanderyst EN SUELOS SULFATADOS áCIDOS DE CóRDOBA
Enrique Combatt C,Alfredo Jarma O,Libardo Maza A.
Revista MVZ Córdoba , 2008,
Abstract: Objective. To assess the effect of different doses of lime in acid sulphate soils and physiological responses of two species of grasses, Cynodon nlemfuensis Vanderyst and Brachiaria decumbens Stapf. Materials and methods. The work was carried out during 2006 in acid sulfate soils at El Deseo farm (Ciénaga de Oro - Córdoba, Colombia), where 3, 6 and 9 tons/ha of agricultural lime was applied and two grass species, Cynodon nlemfuensis Vanderyst (pasto estrella) and Brachiaria decumbens Stapf (pasto brachiaria) were planted. The responses considered during 5 mowings were the chemical features of the soil, fresh and dry weight of each genotype and the leaf/stem ratio. An experiment of complete random blocks was designed using a structure of divided plots, where the main plots corresponded to the grasses and the subplots to the lime doses. Results. The most outstanding results suggested that the pH values and aluminum in the soil concentrations fall significantly with the quantity of applied lime, decreasing up to 80%. In general, the interchangeable bases increased with the lime dosage and the contents of the microelements decreased considerably over time, although this was not evident for the lime. Independently of genotype, the production of fresh biomass showed a linear relationship within lime dosage (y=0,656x + 11,99; R2=0.92); the dry mass and the leaf/stem ratio were always greater for B. decumbens compared to C. nlemfuensis, independent of lime dosage.
Glyphosate e nitrgênio no controle de Brachiaria decumbens Stapf em capineiras estabelecidas
Abreu, Joadil Gon?alves de;Evangelista, Ant?nio Ricardo;Souza, Itamar Ferreira de;Rocha, Gudesteu Porto;Soares, Lécio Queiroz;Santarosa, Leonardo de Castro;
Ciência e Agrotecnologia , 2006, DOI: 10.1590/S1413-70542006000500023
Abstract: the objective of this experiment was to evaluate the efficiency of the use of the herbicide glyphosate associated with nitrogen fertilization in the control of brachiaria decumbens stapf in elephant grass stocking piles. the experimental design used was a randomized blocks with 17 treatments and three replications. the treatments were arranged in 4x4+1 factorial scheme, namely four doses of glyphosate (0, 720, 1440 e 2160 g/ha/application), four doses of nitrogen (0, 75, 150 e 225 kg/ha/ano) and one additional treatment (control with a hoeing). the application of the nitrogen and glyphosate, in the respective doses were performed immediately after the cutting of elephant grass. the association between glyphosate (2160 g/ha/application) and nitrogen (225 kg/ha/ano) was efficient in the control brachiaria grass in established elephant grass stocking piles. the application of the glyphosate (2160 g/ha/application) reduced the size of the bank of brachiaria grass seeds in the soil in 64%.
Produ o e perfilhamento de Brachiaria decumbens Stapf. em fun o de doses de enxofre  [cached]
Santos Anacleto Ranulfo dos,Monteiro Francisco Antonio
Scientia Agricola , 1999,
Abstract: O experimento foi realizado em casa-de-vegeta o em Piracicaba, S o Paulo, no período de outubro a dezembro de 1996, com Brachiaria decumbens Stapf. cv. Basilisk cultivada em solu o nutritiva e utilizando sílica como substrato. Foi empregado o delineamento de blocos completos ao acaso, com quatro repeti es. O primeiro corte das plantas foi efetuado 40 dias após transplante para os vasos, e o segundo corte 30 dias após o primeiro. Foram avaliadas oito doses de enxofre (0; 2; 4; 16; 32; 48; 64 e 80 mg L-1) na produ o de matéria seca e no número de perfilhos. As doses de enxofre proporcionaram aumentos na produ o de matéria seca da parte aérea e das raízes do capim-braquiária e influenciaram o número de perfilhos no segundo crescimento dessa forrageira.
COMPOSI O QUíMICA DAS GRAMíNEAS Brachiaria decumbens Stapf cv. Basilisk E Brachiaria ruziziensis Germain & Everard EM DIFERENTES IDADES DE CORTE CHEMICAL COMPOSITION OF THE GRASSES Brachiaria decumbens STAPF CV. BASILISK AND Brachiaria ruziziensis GERMAIN & EVERARD IN DIFFERENT CUTTING AGES  [cached]
Beneval Rosa,Gudesteu Porto Rocha,Kléber Tomás de Resende,Ant?nia Ribeiro Zabin
Pesquisa Agropecuária Tropical , 2007, DOI: 10.5216/pat.v27i1.2950
Abstract: Este trabalho foi conduzido no Departamento de Zootecnia da Escola Superior de Agricultura de Lavras, no município de Lavras, Estado de Minas Gerais, no período de julho de 1980 a junho de 1981, para comparar a Brachiaria decumbens Stapf cv. Basilisk e a Brachiaria ruziziensis Germain & Everard em três idades de corte (60, 90 e 120 dias). Utilizou-se um esquema fatorial 3x2, delineamento em blocos casualizados, com quatro repeti es, sendo as três idades de corte e as duas gramíneas os fatores. Foram determinadas as propor es de folhas (F), de hastes (H) e de material morto (MM), bem como os teores médios de matéria seca (MS), de proteína bruta (PB), de fibra bruta (FB), de cálcio (Ca), de magnésio (Mg), de fósforo (P) e de potássio (K). Os resultados permitiram a seguinte conclus o: ambas as gramíneas podem ser usadas tanto para pastejo quanto para fena o com idades entre 60 e 90 dias. PALAVRAS-CHAVE: Planta integral; folhas; hastes; material morto; minerais. This work was conducted at the Departamento de Zootecnia, Escola Superior de Agricultura de Lavras, Lavras, Minas Gerais, from July 1980 to June 1981, to compare Brachiaria decunbens Stapf cv. Basilisk and Brachiaria ruziziensis Germain & Everard at three different growth ages (60, 90 and 120 days). The experiment was studied on a 3 x2 factorial scheme, in randomized blocks, with four repetitions, being the three cutting growth ages and two grasses the factors. The leaves, the stems and the dead material proportion; the contents of dry matter (DM), crude protein (CP), crude fiber (CF), calcium (Ca), magnesium (Mg), phosphorus (P) and potash (K) were determined. The results permitted the following conclusion: both grasses could be used either for grazing or haying with ages between 60 and 90 days. KEY-WORDS: Integral plant; leaves; stems; dead material; minerals.
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