Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Insects Associated with Seeds of Lonchocarpus muehlbergianus Hassl. (Fabaceae) in Tres Barras, Parana, Brazil
Neotropical Entomology , 2002, DOI: 10.1590/S1519-566X2002000300023
Abstract: to find the insects associated with seeds of a brazilian native leguminous plant, lonchocarpus muehlbergianus hassl., fruits were collected from isolated trees in tres barras, parana, brazil. a sample of 500 g of fruits with 2353 seeds was evaluated in the laboratory. it was found that 77.4% of the seeds were not damaged by insects, 12.4% of the seeds were damaged and 10.2% of the seeds were empty. the bruchid species ctenocolum crotonae (f?hraeus) was detected for the first time in this plant. this species was recorded in mato grosso, brazil and, in this paper, the geographical distribution is amplified to include parana state. horismenus missouriensis ashmead (hymenoptera: eulophidae) was also observed in the sample and it is probably a parasitoid of the bruchid larva or pupa. of the 2353 seeds, 4.9% were damaged by c. crotonae and 4.6% had emergence holes of h. missouriensis. larvae of tenebrionidae and curculionidae were also detected feeding on the seeds, representing 2.8% of the total number of the seeds.
Phytotoxicity of the extracts of Lonchocarpus muehlbergianus Hassl. (Fabaceae) leaflets and galls on seed germination and early development of lettuce
Oliveira, Denis Coelho de;Soares, Geraldo Luiz Gon?alves;Isaias, Rosy Mary dos Santos;
Acta Botanica Brasilica , 2008, DOI: 10.1590/S0102-33062008000400020
Abstract: galls induced by euphalerus ostreoides (hemiptera: psyllidae) cause structural and chemical alterations on lonchocarpus muehlbergianus leaflets. healthy and galled leaflet tissues of this plant species are rich in secondary metabolites with potential allelopathic effects. this research compares the allelopathic effects of the aqueous extracts of l. muehlbergianus leaflets and galls on seeds and seedlings of lactuta sativa, and evaluates the chemical impact produced by a gall-inducing insect on the other trophic levels associated with it. the extracts were obtained through static maceration in distilled water (5% p/v). the treatments consisted of aqueous crude extracts and those previously filtered in polyvinylpirrolidone (pvp). after seven days, seedling height was measured, and the radicles were fixed in faa50 for anatomical analyses. healthy leaflet and gall aqueous extracts, and those filtered in pvp, significantly inhibited seed germination, with no significant differences between the two groups. treatments with aqueous extracts reduced seed germination speed and vegetative axis length. plant tissue alterations confirm the phytotoxicity of allelochemical substances present in the extracts. the differences among the treatments indicated that gall formation altered l. muehlbergianus leaflet metabolism, and this could influence the other trophic levels associated with this gall inducing-host plant system.
Flavonoids from Lonchocarpus muehlbergianus
Magalh?es, Aderbal F.;Tozzi, Ana M.G.A.;Magalh?es, Eva G.;Blanco, Ivani S.;Soriano, Maria-Del-Pilar C.;
Anais da Academia Brasileira de Ciências , 2004, DOI: 10.1590/S0001-37652004000400004
Abstract: the light petroleum extract from the roots of lonchocarpus muehlbergianus hassl contained nine flavonoids, including six new ones. these are 2,4-cis-2,4,5,8-tetramethoxy-(2′′,3′′:6,7)-furanoflavan; 2,4-cis-4-hydroxy-2,5,8-trimethoxy-(2′′,3′′:6,7)-furanoflavan; 2,4-cis-2-prenyloxy-4,5,8-trimethoxy-(2′′,3′′:6,7)-fu-ranoflavan; 2,4-cis-2-prenyloxy-4-hydroxy-5,8-dimethoxy-(2′′,3′′:6,7)-furanoflavan; 2',5',6'-trimethoxy-9-(1,1-dimethylallyoxy)-[2′′,3′′:3′,4′]-furanochalcone; 5,6-dimethoxy-(2′′,3′′:7,8)-furanoflavone, identi-fied by analysis of their spectral data (uv, ir, 1h and 13c nmr, 2d-nmr, noe and ms). the natural occurrence of 2,4-dioxygenated flavan derivatives is being reported for the first time. quantitative analysis of the petrol extract, by using reversed-phase hplc, showed that the most abundant flavonoid in the extract is 2,4-cis-2,4,5,8- tetramethoxy-(2′′,3′′:6,7)-furanoflavan.
Flavonoids from Lonchocarpus muehlbergianus  [cached]
Magalh?es Aderbal F.,Tozzi Ana M.G.A.,Magalh?es Eva G.,Blanco Ivani S.
Anais da Academia Brasileira de Ciências , 2004,
Abstract: The light petroleum extract from the roots of Lonchocarpus muehlbergianus Hassl contained nine flavonoids, including six new ones. These are 2,4-cis-2,4,5,8-tetramethoxy-(2,3:6,7)-furanoflavan; 2,4-cis-4-hydroxy-2,5,8-trimethoxy-(2,3:6,7)-furanoflavan; 2,4-cis-2-prenyloxy-4,5,8-trimethoxy-(2,3:6,7)-fu-ranoflavan; 2,4-cis-2-prenyloxy-4-hydroxy-5,8-dimethoxy-(2,3:6,7)-furanoflavan; 2',5',6'-trimethoxy-9-(1,1-dimethylallyoxy)-[2,3:3,4]-furanochalcone; 5,6-dimethoxy-(2,3:7,8)-furanoflavone, identi-fied by analysis of their spectral data (UV, IR, 1H and 13C NMR, 2D-NMR, NOE and MS). The natural occurrence of 2,4-dioxygenated flavan derivatives is being reported for the first time. Quantitative analysis of the petrol extract, by using reversed-phase HPLC, showed that the most abundant flavonoid in the extract is 2,4-cis-2,4,5,8- tetramethoxy-(2,3:6,7)-furanoflavan.
Rea??es de defesas químicas e estruturais de Lonchocarpus muehlbergianus Hassl. (Fabaceae) à a??o do galhador Euphalerus ostreoides Crawf. (Hemiptera: Psyllidae)
Oliveira, Dênis Coelho de;Christiano, Jaciara de Cássia Souza;Soares, Geraldo Luiz Gon?alves;Isaias, Rosy Mary dos Santos;
Brazilian Journal of Botany , 2006, DOI: 10.1590/S0100-84042006000400015
Abstract: galls are plant structure induced in response to stimuli of a gallinducing organism. euphalerus ostreoides induces galls on the adaxial surface of leaflets directly on secondary veins of lonchocarpus muehlbergianus. anatomical analyses were performed to compare healthy leaflets, immature and mature gall tissues. histochemical tests for detection of phenolic derivatives, flavonoids, lignins, lipids and starch were performed to check the chemical impact of gall-inducing action. the lost of sinuosity of epidermal cells, the neoformation of trichomes, of conducting cells, and fibres were the most conspicuous plant responses features to gall induction. mesophyll hiperplasia with maintenance of tissue stratification, and accumulation of lipids, starch, flavones, flavonols and flavanones in gall tissues were observed. nevertheless, the formation of oxonium salts by the reaction with sulfuric acid only in gall tissues was a remarkable feature. the results suggested that l. muehlbergianus was submitted to a high oxidative stress induced by the action of e. ostreoides. it was possible to conclude that the structural and chemical alterations observed were considered as plant defensive reactions against herbivory and adaptive mechanisms that favor the galling insect establishment within plant tissues.
CRESCIMENTO INICIAL DE MUDAS DE Clitoria fairchildiana Howard E Peltophorum dubium (Sprenge) Taub EM DIFERENTES CONDI ES DE SOMBREAMENTO
Rita C.Q. Portela,Isabela Lobato Silva,Fatima C.M. Pin?-Rodrigues
Ciência Florestal , 2001,
Abstract: Este experimento teve como objetivo avaliar a influência do sombreamento no crescimento de mudas de Peltophorum dubium (Canafístula) e Clitoria fairchildiana (Sombreiro), espécies utilizadas no reflorestamento de encostas do município do Rio de Janeiro. As sementes foram colhidas em diversas matrizes e semeadas em sacos plásticos. As porcentagens de sombreamento testadas foram: 0% (sol pleno), 30%, 50% e 75%. A instala o do experimento iniciou-se um mês após a semeadura. O parametro altura foi analisado aos 30, 60, 90, 120 e 150 dias após a semeadura. O peso da matéria seca da raiz foi analisado aos 150 dias. Os resultados demostraram que as espécies estudadas apresentam diferentes respostas para os parametros analisados. Para o plantio imediato recomenda-se a produ o de mudas de Sombreiro sob o sombreamento de 30% e de Canafístula, sob sol pleno, 30% ou 75% de sombra. Na produ o de mudas para estocagem, seria indicado para o Sombreiro, a produ o a sol pleno e para Canafístula, as mudas poderiam ser mantidas sob 50% de sombreamento. Ambas as espécies podem ser plantadas sob pleno sol, 30%, 50% e 75% de sombreamento, sendo indicadas para a implanta o de reflorestamentos ou para enriquecimento de área degradadas.
Crescimento inicial de mudas de Bombacopsis glabra (Pasq.) A. Robyns sob condi o de sombreamento
Scalon Silvana de Paula Quint?o,Mussury Rosilda Mara,Rigoni Marilúcia Rossi,Scalon Filho Homero
Revista árvore , 2003,
Abstract: Este experimento foi desenvolvido com o objetivo de estudar o crescimento de mudas de Bombacopsis glabra (Pasq.) A. Robyns (castanha-do-maranh o) sob diferentes intensidades luminosas. A capacidade de emergência das plantulas foi determinada pela porcentagem e pelo índice de velocidade de emergência, utilizando quatro repeti es de 100 sementes (1 semente/saco). Após 40 dias, 75 mudas foram transferidas para condi es de 30 e 50% de sombreamento e para pleno sol. O desenvolvimento das mudas foi conduzido em delineamento de blocos casualizados, com três repeti es de cinco mudas, nas quais foram avaliados a altura do caule e o diametro do colo aos 61, 82, 103 e 124 dias após a emergência das plantulas; o teor de clorofila a, b, total e a raz o a/b; a massa seca da planta (MS); a área foliar (AF); a taxa de crescimento relativo (TCR); a raz o de área foliar (RAF); a taxa assimilatória líquida (TAL); e a sobrevivência aos 103 e 124 dias após a emergência, quando o experimento foi encerrado. As sementes apresentaram 95% de emergência e alto de índice de velocidade de emergência (1,7). As mudas apresentaram 100% de sobrevivência em todos os tratamentos. Os níveis de luz estudados n o afetaram a sobrevivência das mudas, o diametro do caule, a área foliar, a clorofila a e b, a TCR, a TAL e a RAF, nos intervalos de tempo estudados. As mudas crescidas sob 50% de sombra apresentaram maior altura, maior clorofila total e menor rela o a/b. A castanha-do-maranh o é uma espécie de fácil propaga o, apresentando bom desenvolvimento das mudas sob pleno sol e tolerando o sombreamento de 30 e 50%.
Efeito do Sombreamento sobre o Teor de Clorofila e Crescimento Inicial do Jequitibá-rosa Effect of Shadeness Over Chlorophyll Level and Initial Growth of Cariniana legalis
Gizelda Maia Rego,Edilberto Possamai
Pesquisa Florestal Brasileira , 2011, DOI: 10.4336/2012.pfb.53.179
Abstract: Com o objetivo de avaliar os efeitos de períodos de sombreamento sobre o crescimento inicial e concentra es de clorofila em mudas de jequitibá- rosa (Cariniana legalis), foi instalado um experimento no viveiro de pesquisa da Embrapa Florestas, em Colombo, PR. O delineamento experimental foi o de blocos ao acaso, com cinco tratamentos e quatro repeti es. Os tratamentos estabelecidos foram: 100 % (pleno sol); 70 %; 64 %, 44 % e 34 % de radia o solar incidente. A altura e diametro do coleto foram monitorados em intervalos de 30 dias, dos 60 aos 180 dias após a emergência (DAE). O peso da matéria seca total, aérea e radicial, área foliar, clorofila a e b e clorofila total, foram medidos aos 180 DAE. O percentual de 63,07 % de RFA (radia o fotossinteticamente ativa) proporcionou o maior crescimento em altura das mudas. As maiores médias de diametro do coleto ocorreram com as mudas submetidas a pleno sol. O oposto foi observado com a área foliar, onde observaram-se as maiores médias quando as mudas foram submetidas ao maior percentual de sombreamento (34 % de luminosidade). O acúmulo de matéria seca total foi estimado para 54,40 % de RFA. Os teores de clorofila a e b foram maiores nas folhas das mudas sombreadas. Concluiu-se que mudas do jequitibá-rosa, em sua fase inicial, apresentam bom crescimento quando cultivadas na faixa de 54 % a 64 % de luminosidade. Toevaluate the effects of periods of shadeness over the initial growth and concentrations of chlorophyll in Cariniana legalis (Mart.) Kuntze seedlings, an experiment was installed in the research nursery of Embrapa Florestas, at Colombo/PR, Brazil. It was utilized randomized blocks design with five treatments and four replications. The treatments established were: 100% (entire light); 70%, 64%, 44% and 34% of sun radiation. Monitoring of height and diameter were made under intervals of 30 days, from 60o to 180o day after emergency (DAE). Air total dry matter weight of roots, leaf area, chlorophyll a, chlorophyll b and total chlorophyll were measured 180 days after emergency. FAR (Photosynthetic Active Radiation) of 63, 07% led to the best seedling growth in height. Best diameter averages of the region that divides roots from stem occurred with seedlings submitted to entire light. The contrary was observed with leaf area, where major averages were observed when seedlings were submitted to shadeness (34% of light). Dry matter estimates accumulated on 54,40 % of FAR. Chlorophyll a and b levels were higher in the leaves of seedlings cultivated in shadow. Seedlings of Cariniana legalis, at the first phas
Descri??o e discrimina??o de formas de nervuras foliares utilizando a representa??o polinomial cúbica de Hermite
Brito Júnior, Agostinho de Medeiros;Tozzi, Clésio Luis;Tozzi, Ana Maria Goulart de Azevedo;
Acta Botanica Brasilica , 1997, DOI: 10.1590/S0102-33061997000200007
Abstract: this paper describes a method for leaf vein shape characterization using hermite polynomial cubic representation. the elements associated with this representation are used as secondary vein descriptors and their discriminatory potential are analyzed based on the identification of two legume species (lonchocarpus muehlbergianus hassl. and l. subglaucescens mart, ex benth.). the elements of hermite geometry influence a curve along all its extension allowing a global description of the secondary vein course by a descriptor of low dimensionality. the obtained results shown the analyzed species can be discriminated by this method and it can be used in addition to commonly considered elements in the taxonomic process.
Isocordoin Derivatives From the Root Extract of Lonchocarpus xuul
Yam-Puc, Alejandro;Pe?a-Rodríguez, Luis M.;
Journal of the Mexican Chemical Society , 2009,
Abstract: two natural isocordoin derivatives, dihydroisocordoin (1) and flemistrictin b (2), were isolated from the root extract of lonchocarpus xuul. both metabolites were identified on the basis of their spectroscopic data and by comparing them with those reported in the literature.
Page 1 /100
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.