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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Persistence of Plasmodiophora brassicae : influence of non-host plants, soil fauna and organic material /

Friberg, Hanna, January 2005 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 5 uppsatser.
52

Studies of the persistence of red clover cultivars in Sweden : with particular reference to Sclerotinia trifoliorum /

Öhberg, Helena, January 2008 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2008. / Härtill 4 uppsatser.
53

Studium sekundárních metabolitů v rostlinných explantátových kulturách I / The study of secondary metabolites in plant tissue cultures I

Blahušová, Adriana January 2018 (has links)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy Candidate: Adriana Blahušová Supervisor: PharmDr. Marie Kašparová, Ph.D. Title of diploma thesis: The study of secondary metabolites in plant tissue cultures I A principal precondition for successful elicitation used to increase the production of secondary metabolites is, among other, finding a suitable elicitor, its concentration and the optimal period of time of the action of the elicitor on the plant culture in vitro, which was the aim of the present diploma thesis. The effect was examined of a 6, 24, 48 and 168 hour action of the solution of chitosan (in four concentrations) on the production of flavonoids in the suspension culture Trifolium pratense L. (variety Sprint, Tempus and DO-8). The culture was cultivated in Gamborg medium to which 2 mg/l of 2,4- dichlorophenoxyacetic acid and 2 mg/l of 6-benzylaminopurine were added, at the temperature of 25řC and 16 hours light/8 hours dark period. The best elicitation effect of chitosan on the production of flavonoids was the lowest concentration of 1 mg/100ml in all three studied varieties after 48 hours of application.
54

Včelařsky významné pylodárné rostliny letního a podzimního aspektu na území Zbudovských Blat (okolí obce Hlavatce) / Important plants in terms of pollen for bee-keeping in the summer and autumn aspect in the "Zbudovska Blata" region

FIŠROVÁ, Nikola January 2018 (has links)
The work deals with pollen analysis which was focused on botanical origin of pollen loads where the samples were taken in the area of Zbudkovské morasses in the surroundings of village Hlatavce, district of České Budějovice. The goal of this work was to evaluate individual plant species in the food of honey bee and its flight range from the beehive, supposed to be cca 2km. The samples were taken in 2017, summer and autmn period with a facility called pollen traps. The analysis was based on the classification of pollen loads according to individual colors. The structure of the pollen grain was analysed under a microscope (exina and apertures) and indentified according to database. Microscopic formulation was prepared by deluting pollen loads in glycerin and water. The work was supplementid by photos. Totally there were found 24 kinds of pollen grains in the specific period, the greatest part of pollen loads consisted of 38,22% trifolium types.
55

Produção de trevo persa em função da época de semeadura e desfolha. / Persian clover production depending on sowing time and defoliation.

Duarte, Gabriela da Silveira 19 April 2016 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2016-09-23T14:24:20Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) TESE_Gabriela Duarte.pdf: 1041923 bytes, checksum: bf1fc071fc423d74913856ac877361d9 (MD5) / Made available in DSpace on 2016-09-23T14:24:20Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) TESE_Gabriela Duarte.pdf: 1041923 bytes, checksum: bf1fc071fc423d74913856ac877361d9 (MD5) Previous issue date: 2016-04-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / O objetivo deste trabalho foi avaliar a produtividade de forragem e sementes de trevo persa (Trifolium resupinatum) submetido a diferentes épocas de semeadura. O experimento foi realizado na Embrapa Clima Temperado –ETB, Pelotas - RS, com a cultivar BRS Resteveiro. O delineamento experimental foi em blocos completos ao acaso, com quatro repetições. Para as variáveis referentes à forragem colhida, foram testadas cinco épocas de semeadura (março, abril, maio, junho e julho) em dois anos de cultivo (2014 e 2015). Enquanto que para a produção de sementes, além das cinco épocas de semeadura, ainda foi verificado o efeito do corte (no momento do aparecimento das primeiras flores). Houve interação significativa (P<0,05) entre os fatores época de semeadura e ano para todas as variáveis relacionadas a colheita de forragem. Enquanto que, para as variáveis referentes à produção de sementes, somente não houve interação entre os fatores época de semeadura e corte para a variável peso de mil sementes..A colheita de forragem de trevo persa apresenta respostas distintas em função das condições climáticas de cada ano experimental. Quando as plantas não são submetidas ao corte, a semeadura pode ocorrer até o 170º dia do ano para que se obtenham máximos rendimentos de sementes. As plantas submetidas ao corte são muito sensíveis ao retardamento da época de semeadura quando o objetivo é a produção de sementes. O retardamento da época de semeadura (até o dia 150 do ano) e, consequentemente, do corte, aumenta a sincronização da maturação das flores e a qualidade fisiológica das sementes. No entanto, semeaduras após o centésimo dia do ano, com posterior intervenção do corte, determinam rendimentos insignificantes de sementes. / The aim of this study was to evaluate Persian clover (Trifolium resupinatum) forage and seed productivity under different sowing dates. The experiment was carried out at Embrapa Clima Temperado - ETB, Pelotas - RS, with the cultivar BRS Resteveiro in a randomized complete block design with four replications. In order to evaluate the harvested forage, five sowing dates were tested (March, April, May, June and July) during two crop years (2014 and 2015). For the evaluation of seed production, besides the five sowing dates, it was also observed the effect of cutting (at the time of the appearance of the first flowers). There was a significant interaction (P <0.05) among the factors sowing time and year for all variables related to forage crop, whereas for the variables related to seed production, there was no interaction only among the factors sowing time and cutting to the variable weight of a thousand seeds. The Persian clover forage crop shows different answers depending on the climatic conditions of each experimental year. When the plants are not subject to cutting, the sowing can occur until the 170th day of the year in order to obtain maximum yields of seed. The plants submitted to cutting are very sensitive to delayed sowing time when the goal is the production of seeds. The delay of sowing time (until the 150th day of the year) and, consequently the cutting, increases the synchronization of flowers maturation and seed physiological quality. However, sowings after the hundredth day of the year, with further cutting intervention, result in insignificant yields of seed.
56

Sekundární metabolity rostlinných kultur in vitro I / Secondary metabolites of plant cultures in vitro I

Zlochová, Pavlína January 2017 (has links)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy Candidate: Pavlína Zlochová Supervisor: PharmDr. Marie Kašparová, Ph.D. Title of diploma thesis: Secondary metabolites of plant cultures in vitro I. Key words: Suspension cultures, Trifolium pratense, phytoestrogens, flavonoids, isoflavonoids Explant cultures are source of plant secondary metabolites. Nevertheless the production of secondary metabolites is usually low in explant cultures. This production can be increased by elicitation metods. Suitable elicitor is added into the cultivate medium and leads to gene expression and production of secondary metabolites. The aim of this study was to observe the influence of sodium chloride on the production of flavonoids and isoflavonoids by the Trifolium pratense L. suspension culture (Tempus variety). The culture was cultivated on Gamborg nutriet medium with addition of 2 mg.l-1 2,4- dichlorophenoxyacetic acid and 2 mg.l-1 6-benzylaminopurine. Cultivation proceed in 25řC temperature and 16 hours light/8 hours dark period. Then determination of flavonoids in according to Czech Pharmacopoeia 2009 and the determination of isoflavonoids by HPLC method was performed. The best elicitation effect on the production of flavonoids was 175 mmol.l-1 of sodium chloride after a 3...
57

Evaluación de plantas fitoacumuladoras en suelos aluviales con alto nivel de cobre disponible / Phytoaccumulator plants assessment in alluvial soils with a high available copper level

Silva Caris, Gastón Aníbal January 2013 (has links)
Memoria para optar al Título Profesional de: Ingeniero Agrónomo / Se evaluó el potencial fitoacumulador de ballica (Lolium perenne L.) y/o trébol blanco (Trifolium repens L.) para ofrecer una alternativa de limpieza de sitios contaminados con cobre. Se realizó un ensayo con suelos de la V Región (Valparaíso) de Chile cultivados con vid de mesa (Vitis vinifera L.) que mostraban un alto (TB: bajos rendimientos de V. vinifera), bajo (TA: altos rendimientos de V. vinifera) e intermedio (TM: rendimientos medios de V. vinifera) nivel de Cu (DTPA) disponible (140, 40 y 90 mg kg-1, respectivamente). Durante el año 2013 y en invernadero, cada suelo (cinco repeticiones) fue sembrado con L. perenne y/o T. repens en macetas. Después de ocho meses las plantas fueron cosechadas para obtener la masa de materia seca y los contenidos de Cu tanto en los tejidos aéreos como radicales de las plantas. Así también, se determinaron los contenidos de Cu disponible, intercambiable y total de los suelos. Para las condiciones iniciales de CuDTPA intermedio y alto (TM y TB), el metal fue acumulado principalmente a nivel de raíces en los cultivos individuales y la combinación de ellos, pero ballica y ballica+trébol fueron más eficientes en cuanto a la absorción de Cu. Si bien las especies vegetales son capaces de remover el metal de los suelos, los contenidos de Cu al final del ensayo permanecieron altos (hasta 50 mg kg-1 de Cu disponible), denotando la necesidad de realizar estudios de más largo plazo y de verificar que estos resultados se repitan a nivel de campo. / To assess their potential as copper phytoaccumulators in soils and to offer a cleanup alternative of contaminated sites, ryegrass (Lolium perenne L.) and/or white clover (Trifolium repens L.) were used. The study was conducted with soil from the 5th Region (Valparaíso) of Chile cultivated with table grapes (Vitis vinifera L.) and showing a high (TB: low yields of V. vinifera), low (TA: high yields of V. vinifera) and intermediate (TM: medium yields of V. vinifera) levels of available Cu (DTPA). During 2013 and in a greenhouse assay, each soil (five replications) was sowed with L. perenne and/or T. repens in pots. After eight months plants were harvested to obtain dry matter and Cu contents in plant aerial and root tissues. Available, exchangeable and total Cu were measured also in soils. Under initial high and intermediate levels of CuDTPA conditions (TB and TM), metal was accumulated mainly at roots level in single and combined crops, but single ryegrass and ryegrass+clover were more efficient in the Cu uptake. Although species are able to remove metal from soils, the Cu contents at the end remained high (up to 50 mg kg-1 of available Cu), indicating that long-term trials are necessary and confirm these results at field level.
58

A taxonomic and biogeographic analysis of the <i>Trifolium gracilentum</i> species complex

Rogers, Lauren Marie 06 August 2019 (has links)
No description available.
59

A comparative study of de-icing salts (sodium chloride and calcium magnesium acetate) on the growth of some roadside plants of England

Akbar, K.F., Headley, Alistair D.D., Hale, William H.G., Athar, M. January 2006 (has links)
No
60

Estudo químico de diferentes acessos de trevo-vermelho (Trifolium pratense L.) e atividades biológicas / Chemical study of different accessions of red clover (Trifolium pratense L.) and biological activities

Ramos, Graziele Pereira January 2010 (has links)
O trevo-vermelho (Trifolium pratense L.), uma das leguminosas forrageiras mais utilizadas na agricultura mundial, contém as isoflavonas formononetina e biochanina A, e em menores concentrações daidzeína e genisteína. Estes compostos têm ganhado muito interesse devido aos relatos de seus benefícios à saúde humana. Recentemente, no ano de 2009, esta espécie foi incluida na lista da Relação Nacional de Plantas Medicinais de Interesse ao SUS (RENISUS) que contém plantas medicinais com potencial de gerar produtos para serem produzidos e distribuídos pelo SUS. Mas é importante destacar que não existem estudos de quantificação de isoflavonas em plantas de trevo-vermelho cultivados no Brasil. Os objetivos deste trabalho foram validar método de análise de amostras de trevo-vermelho por Cromatografia Líquida de Alta Eficiência (CLAE); quantificar quatro isoflavonas em 78 acessos de trevo-vermelho; verificar as modificações sazonais na concentração de três acessos de trevo-vermelho; aumentar os níveis de isoflavonas através de melhoramento genético; e determinar a atividade anti-inflamatória in vivo e in vitro e de atividade de inibição da acetilcolinesterase de um extrato seco de trevo-vermelho. Para analisar as plantas por CLAE, estas foram hidrolisadas, separadas por diclorometano, e ressuspendidas em metanol. O método de CLAE usado foi validado. As isoflavonas (daidzeína, genisteína, formononetina e biochanina A) foram quantificadas em 78 acessos de trevo-vermelho, os conteúdos das agliconas (expressos em μg/g de planta seca, n=3) destes compostos variaram entre 0,00 a 137,91 para daidzeína; 14,70 a 516,51 para genisteína; 452,97 a 28548,65 para formononetina; e 1967,64 a 20145,27 para biochanina A, e a concentração total de isoflavonas variou entre 9,81 e 36,36 mg/g. O estudo sazonal mostrou que a concentração total das isoflavonas não difere entre as estações, mas verifica-se que na primavera (quando o trevo-vermelho está no estágio reprodutivo) se observam concentrações inferiores, e no inverno (quando a planta está no estágio vegetativo) são encontradas concentrações mais elevadas. No estudo de melhoramento genético foi possível observar um aumento na concentração total de isoflavonas. A atividade anti-inflamatória in vitro foi medida através da mobilização de leucócitos, pelo ensaio de quimiotaxia na câmara de Boyden. A atividade anti-inflamatória in vivo foi avaliada pelo teste de edema de pata de rato induzido por carragenina. Os resultados do teste anti-inflamatório in vitro mostram que houve significante inibição da migração dos leucócitos nas concentrações de 100,0 (94,73% de inibição), 50,0 (95,39% de inibição), 25,0 (94,73% de inibição), 10,0 (84,68% de inibição) e 5,0 (78,75% de inibição) μg/mL de extrato seco de trevo-vermelho. O teste anti-inflamatório in vivo demonstrou significante atividade nas doses testadas, 100 e 50 mg/kg de extrato seco de trevo-vermelho. O percentual médio de inibição do edema foi 63,37%. O teste da inibição da acetilcolinesterase não demonstrou atividade. Os resultados deste estudo sugerem que se pode produzir plantas com concentrações mais elevadas de isoflavonas para a produção de fitomedicamentos com maior qualidade, e o extrato de trevo-vermelho pode ser adequado para o tratamento de doenças inflamatórias. / Red clover (Trifolium pratense L.) is one of the most utilized forage legume in the world agriculture and contains the isoflavones formononetin and biochanin A, and in smaller concentration daidzein and genistein. These compounds have gained a high interest due to their human health benefits. Recently this species was included in the list of Relação Nacional de Plantas Medicinais de Interesse ao SUS (RENISUS) which contains medicinal plants that have potential to generate products to be produced and distributed by SUS. But it is important to highlight that does not exist any study of isoflavones quantification in red clover plants cultivated in Brazil. The aims of this work were to validate a method to analize red clover samples by High Performance Liquid Cromatography (HPLC); to quantify four isoflavones compounds in 78 red clover accessions; to verify seasonal modifications in the isoflavone concentration of three red clover accessions; to increase isoflavones levels through plant breeding; and to determine in vivo and in vitro anti-inflammatory activity, and inhibitory activity of acetylcholinesterase of a red clover dry extract. To analyze the plants by HPLC, they were hydrolyzed, separated by dichloromethane, and resuspended with methanol. The HPLC method used was validated. Isoflavones (daidzein, genistein, formononetin and biochanin A) were quantified in 78 red clover accessions, the aglycone contents (expressed in μg/g of dry material, n=3) of these compounds varied from 0.00 to 137.91 to daidzein; 14.70 to 516.51 to genistein; 452.97 to 28548.65 to formononetin; and 1967.64 to 20145.27 to biochanin A, and the total isoflavone concentration ranged between 9.81 and 36.36 mg/g. The seasonal study showed that the total concentration of isoflavones is not statistically different at different seasons, but is possible to verify that at spring (when red clover is at reproductive stage) we could observe the lowest concentration, and at winter (when red clover is at vegetative stage) we found the highest concentration. In the breeding study we could observe an increase in the total concentration of isoflavones. The in vitro anti-inflammatory activity was measured towards by leucocytes mobilization, by chemotaxis assay in Boyden´s chamber. The in vivo anti-inflammatory activity was tested by a carrageenan-induced rat paw edema test. The results of anti-inflammatory in vitro test showed that there was a significant inhibition of leukocyte migration at concentrations of 100.0 (94.73% of inhibition), 50.0 (95.39% of inhibition), 25.0 (94.73% of inhibition), 10.0 (84.68% of inhibition) and 5.0 (78.75% of inhibition) μg/mL of red clover dry extract. The in vivo anti-inflammatory test demonstrated significant activity in the tested doses, 100 and 50 mg/kg of red clover dry extract. The average of edema inhibition percentage was 63.37%. The inhibition of acetylcholinesterase test did not show activity. The results of this study suggest that we can select or produce plants with higher concentrations of isoflavones to produce phytomedicines with higher quality, and the red clover extract might be suitable for the treatment of inflammatory diseases.

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