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Calagem e aduba??o organica na produ??o de biomassa e óleo essencial em Lippia citriodora (Kunth)
Souza, M.F.;Souza Junior, I.T;Gomes, P.A.;Fernandes, L.A.;Martins, E.R.;Costa, C.A.;Sampaio, R.A.;
Revista Brasileira de Plantas Medicinais , 2010, DOI: 10.1590/S1516-05722010000400001
Abstract: the present work aimed to evaluate the effect of liming and bovine fertilization on lippia citriodora kunth phytomass and essential oil production. the experimental design was completely randomized with seven treatments (control; ca and mg sulfate; limestone; ca and mg silicate; ca and mg sulfate + manure; limestone + manure; ca and mg silicate + manure) and two harvest seasons, with four replicates. soil adjustment showed to be a necessary procedure for lippia citriodora development. independently of the harvest season, fresh and dry matter yields were higher under treatments with bovine manure (32 t ha-1); however, no effect of treatments was observed on essential oil concentration.
Growth, biomass allocation and photosynthesis of Rolandra fruticosa (asteraceae) in response to shade
Dias-Filho, Moacyr B.;Chagas Júnior, Aloisio F.;
Planta Daninha , 2000, DOI: 10.1590/S0100-83582000000100007
Abstract: the effects of shade on growth, biomass allocation patterns and photosynthetic response was examined for rolandra fruticosa (l.) kuntze, a common perennial weed shrub in cultivated pastures and agricultural areas of brazilian amazonia, for plants grown in full sunlight and those shaded to 30 % of full sunlight over a 34-d period. specific leaf area and leaf area ratio were higher for shade plants during all the experimental period. shade plants allocated significantly less biomass to root tissue than sun plants and relative growth rate was higher in sun plants. sun leaves had significantly higher dark respiration and light saturated rates of photosynthesis than shade leaves. the apparent quantum efficiency was higher for shade leaves, while light compensation point was higher for sun leaves. these results are discussed in relation to their ecological and weed management implications.
Conversion of Natural Aldehydes from Eucalyptus citriodora, Cymbopogon citratus, and Lippia multiflora into Oximes: GC-MS and FT-IR Analysis ?  [PDF]
Igor W. Ouédraogo,Michael Boulvin,Robert Flammang,Pascal Gerbaux,Yvonne L. Bonzi-Coulibaly
Molecules , 2009, DOI: 10.3390/molecules14093275
Abstract: Three carbonyl-containing extracts of essential oils from Eucalyptus citriodora (Myrtaceae), Cymbopogon citratus (Gramineae) and Lippia multiflora (Verbenaceae) were used for the preparation of oximes. The reaction mixtures were analyzed by GC-MS and different compounds were identified on the basis of their retention times and mass spectra. We observed quantitative conversion of aldehydes to their corresponding oximes with a purity of 95 to 99%. E and Z stereoisomers of the oximes were obtained and separated by GC-MS. During GC analysis, the high temperature in the injector was shown to cause partial dehydratation of oximes and the resulting nitriles were readily identified. Based on FT-IR spectroscopy, that revealed the high stability and low volatility of these compounds, the so-obtained oximes could be useful for future biological studies.
Nitrogen content, nitrate reductase activity, and biomass of kimpul (Xanthosoma sagittifolium) on shade and nitrogen fertilizer variation
ISNAINI CHOIRUL LATIFA,ENDANG ANGGARWULAN
Nusantara Bioscience , 2009,
Abstract: Latifa IC, Anggarwulan E. 2009. Nitrogen content, nitrate reductase activity, and biomass of kimpul (Xanthosoma sagittifolium) on shade and nitrogen fertilizer variation. Nusantara Bioscience 1: 65-71. The mains of this research were to study the effect of shade and nitrogen fertilizer variation and also their interaction to nitrogen content, nitrate reductase activity, and biomass of kimpul (Xanthosoma sagittifolium (L.) Schott.). This research was arranged in randomized complete block design (RCBD) with two factor, they were shade variation which contained 3 levels (0%, 50%, and 75% of shade) and nitrogen fertilizer dosage variation which contained 4 levels (0; 0.0625; 0.125; dan 0.25 g ZA/kg of soil of the dosage of ZA fertilizer). The variables of the research were nitrogen content, nitrate reductase activity, fresh weight, dry weight, and shoot/root ratio. The collected data were analyzed with General Linear Model Univariate, and continued with Duncan’s Multiple Range Test (DMRT) on 5% significantly levels. The result showed that the shade treatment affected nitrogen content, fresh weight and shoot/root ratio. The fertilizer application and the interaction between shade and fertilizer application was affected to all variabels. The treatment of 75% shade and 0.25 g ZA/kg of soil of ZA fertilizer dosage increased nitrogen content (5.32%) and fresh weight (420.88 g). The treatment without shade and 0.25 g ZA/kg of soil, dosage of ZA fertilizer increased nitrate reductase activity (260.58 μ mol NO2-/g/hour) and dry weight (53.92 g). The treatment of 50% shade and 0 g ZA/kg of soil of ZA fertilizer dosage increased shoot/root ratio (0.98).
Effect of organic fertilization on the shoot biomass of chemotypes of Lippia alba
Gilberto Iris Souza,Valéria Gomes Momenté,Ildon Rodrigues Nascimento,Horllys Gomes Barreto
Pesquisa Aplicada & Agrotecnologia , 2010, DOI: 10.5777/987
Abstract: El experimento se llevó a cabo en el área de cultivo orgánico de la Estación Experimental de lo Campus Universitario de Gurupi de la Universidad Federal de Tocantins – UFT, ubicado en la latitud 11° 43’ 45” S y Longitud 49° 04’ 07” W, con una altitud media de 280 m. Se evaluó el efecto de la fertilización orgánica en los aspectos vegetativos de tres quimiotipos de Salvia morada Lippia alba (Mill.), N. E. Brown (quimiotipos I: mirceno-citral, II: citral-limoneno y III: carvona-limoneno). El experimento fue arreglado en un factorial (3 x 4) en el dise o de bloques al azar con tres repeticiones [(tres quimiotipos y cuatro dosis de abono orgánico (0, 2, 4 y 6 kg m-2 de estiércol bovino curado)]. Las parcelas fueran composta por diez plantas. Las características evaluadas fueron: altura de la planta, número de hojas, el número de ramas principales, masa fresca y seca de hojas, la productividad de masa fresca y seca de hojas. El quimiotipo III se destacó en relación con otros. Las dosis de abono orgánico proporcionaran un aumento lineal de los promedios de las características evaluadas de las plantas. La dosis de 4 kg m-2 de estiércol bovino curado es la más adecuada para los tres quimiotipos. The experiment was conducted in and area of organic cultivation of the Sector of Olericulture of the Experimental Station of the University Campus of Gurupi, Universidade Federal do Tocantins – UFT (Federal University of Tocantins), located in the south latitude 11o 43’ 45” and west longitude 49o 04’ 07” with average height of 280 m. It was evaluated the effect of the organic fertilization over phytotechnical aspects in three chemotypes of Lippia alba (Mill.) N. E. Brown (chemotypes I: myrcene-citral; II: citral-limonene and III: carvone-limonene). The experiment was factorial (3 x 4) in a randomized block design with three replications [(three chemotypes and four doses of organic fertilizer (0, 2, 4 and 6 kg m-2)]. The plots were formed by ten plants. The characteristics evaluated were: plant height, number of leaves, number of main branches, fresh and dry matter of leaves, yield of fresh and dry leaf matter. The chemotype III compared to the others was noteworthy. The fertilization rates provided a linear increase in mean traits of plants. The dose of 4 kg m-2 of organic tanned cattle manure is most suitable for the three chemotypes. O experimento foi conduzido em área de cultivo organico do Setor de Olericultura da Esta o Experimental do Campus Universitário de Gurupi, Universidade Federal do Tocantins – UFT, situado na latitude sul 11o43’45” e longitude oeste 49o04’
Physiological responses of two tropical weeds to shade: I. Growth and biomass allocation
Dias-Filho, Moacyr Bernardino;
Pesquisa Agropecuária Brasileira , 1999, DOI: 10.1590/S0100-204X1999000600004
Abstract: ipomoea asarifolia (desr.) roem. & schultz (convolvulaceae) and stachytarpheta cayennensis (rich) vahl. (verbenaceae), two weeds found in pastures and crop areas in brazilian amazonia, were grown in controlled environment cabinets under high (800-1000 μmol m-2 s-1) and low (200-350 μmol m-2 s-1) light regimes during a 40-day period. for both species leaf dry mass and leaf area per total plant dry mass, and leaf area per leaf dry mass were higher for low-light plants, whereas root mass per total plant dry mass was higher for high-light plants. high-light s. cayennensis allocated significantly more biomass to reproductive tissue than low-light plants, suggesting a probably lower ability of this species to maintain itself under shaded conditions. relative growth rate (rgr) in i. asarifolia was initially higher for high-light grown plants and after 20 days started decreasing, becoming similar to low-light plants at the last two harvests (at 30 and 40 days). in s. cayennensis, rgr was also higher for high-light plants; however, this trend was not significant at the first and last harvest dates (10 and 40 days). these results are discussed in relation to their ecological and weed management implications.
Crescimento de mudas de pau-brasil (Caesalpinia echinata Lam.), submetidas a cinco níveis de sombreamento
Aguiar, Francismar Francisco Alves;Kanashiro, Shoey;Tavares, Armando Reis;Nascimento, Thais Denise Rodrigues do;Rocco, Fabrício Melito;
Revista Ceres , 2011, DOI: 10.1590/S0034-737X2011000600008
Abstract: the aim of this study was to evaluate the growth of seedlings of caesalpinia echinata lam, subjected to five levels of shade. the seedlings, with 18 months of age, were subjected to 0%, 20, 40, 60 and 80% shade, obtained by with black polypropylene screen. the highest values for heights were obtained in plants grown under 20, 40 and 60% shade. plants in full sun and 20% shade showed a higher stem base diameter; lower height/stem base diameter ratio, which reveals more balanced growth. the larger number of leaves was obtained in plants under a full sun. considering the biomass allocation, increasing luminosity occasioned higher shoot, root and total dry mass accumulation and lower shoot/root ratios, suggesting greather investment of biomass to the roots. the highest values of dickson′s quality index were observed in seedlings grown under lower levels of shading, being a good indicator of quality seedlings.
Growth and biomass allocation of the C4 grasses Brachiaria brizantha and B. humidicola under shade
DIAS-FILHO, MOACYR BERNARDINO;
Pesquisa Agropecuária Brasileira , 2000, DOI: 10.1590/S0100-204X2000001200003
Abstract: the growth and biomass allocation responses of the tropical forage grasses brachiaria brizantha cv. marandu and b. humidicola were compared for plants grown outdoors, in pots, in full sunlight and those shaded to 30% of full sunlight over a 30day period. the objective was to evaluate the acclimation capacity of these species to low light. both species were able to quickly develop phenotypic adjustments in response to low light. specific leaf area and leaf area ratio were higher for low-light plants during the entire experimental period. low-light plants allocated significantly less biomass to root and more to leaf tissue than high-light plants. however, the biomass allocation pattern to culms was different for the two species under low light: it increased in b. brizantha, but decreased in b. humidicola, probably as a reflection of the growth habits of these species. relative growth rate and tillering were higher in high-light plants. leaf elongation rate was significantly increased on both species under low light; however, the difference between treatments was higher in b. brizantha. these results are discussed in relation to the pasture management implications.
Growth and biomass allocation of the C4 grasses Brachiaria brizantha and B. humidicola under shade
DIAS-FILHO MOACYR BERNARDINO
Pesquisa Agropecuária Brasileira , 2000,
Abstract: The growth and biomass allocation responses of the tropical forage grasses Brachiaria brizantha cv. Marandu and B. humidicola were compared for plants grown outdoors, in pots, in full sunlight and those shaded to 30% of full sunlight over a 30day period. The objective was to evaluate the acclimation capacity of these species to low light. Both species were able to quickly develop phenotypic adjustments in response to low light. Specific leaf area and leaf area ratio were higher for low-light plants during the entire experimental period. Low-light plants allocated significantly less biomass to root and more to leaf tissue than high-light plants. However, the biomass allocation pattern to culms was different for the two species under low light: it increased in B. brizantha, but decreased in B. humidicola, probably as a reflection of the growth habits of these species. Relative growth rate and tillering were higher in high-light plants. Leaf elongation rate was significantly increased on both species under low light; however, the difference between treatments was higher in B. brizantha. These results are discussed in relation to the pasture management implications.
Temporal variation in the biomass and nutrient status of Azolla filiculoides Lam. (Salviniaceae) in a small shallow dystrophic lake
Trindade, Claudio Rossano Trindade;Albertoni, Edélti Faria;Palma-Silva, Cleber;
Acta Limnologica Brasiliensia , 2011, DOI: 10.1590/S2179-975X2012005000015
Abstract: aim: this study determined the temporal variation of the biomass and the concentrations of carbon, nitrogen and phosphorus in azolla filiculoides lam. in a small (0.5 ha) shallow dystrophic lake located in the city of rio grande (rio grande do sul state, brazil). method: sampling was conducted monthly between november 2000 and october 2001. the macrophytes were collected randomly in three replicates with a circular collector 0.3 m in diameter and subsequently washed with tap water and oven-dried at 60 oc for determination of the dry weight and the nutrient status (i.e., carbon, nitrogen and phosphorus). primary productivity was estimated by the variation in biomass among successive samples. results: a. filiculoides was present in the lake throughout the year and occupied between 50 and 80% of the surface area. the biomass values ranged from 34.2 g dw.m-2, recorded in may (autumn), to 170.9 g dw.m-2 in january (summer). the highest rate of primary productivity was 3.3 g dw.m-2.d-1, observed in june. the concentrations of carbon, nitrogen and phosphorus in the plant ranged between 403 and 551 g.kg-1, 13.4 and 25.7 g.kg-1 and 0.5 and 1.9 g.kg-1, respectively. the water n:p ratio ranged between 19:1 and 368:1. conclusion: the coverage of the surface of the lake by a. filiculoides throughout the study period and the nutritional status of the plant demonstrate the importance of the cycling of nutrients by macrophytes in this aquatic environment. the higher n:p ratio in the water column, compared with other neighboring environments without macrophytes, shows that the enrichment of the lake may result from the biological n-fixation activity produced by a. filiculoides.
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