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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.
41

Propagação e desenvolvimento inicial defícus adhatodifolia Schott ex Spreng. (Moraceae) em diferentes temperaturas, intensidades luminosas e substratos

Gonçalves, Gabriela Granghelli [UNESP] 19 December 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-12-19Bitstream added on 2014-06-13T20:55:04Z : No. of bitstreams: 1 goncalves_gg_me_botfca.pdf: 743632 bytes, checksum: 49215969d8ca452b0ab2f1d95877269a (MD5) / A figueira branca (Ficus adhatodifolia Schott ex Spreng.) é uma espécie nativa do Brasil, utilizada na medicina tradicional devido à atividade anti-helmíntica do seu látex e também é recomendada no tratamento de ancilostomose, icterícia e aos seus frutos são atribuídas propriedades afrodisíacas e estimulantes de memória. A principal forma de coleta da espécie é o extrativismo indiscriminado que pode resultar na perda de diversidade genética e química da espécie. Assim, os estudos sobre propagação e desenvolvimento inicial são importantes ferramentas que podem garantir maiores chances de conservação e manutenção da espécie. O presente trabalho teve como objetivo estudar a propagação sexuada e assexuada e verificar o efeito de diferentes níveis de intensidade luminosa no desenvolvimento inicial e trocas gasosas de F. adhatodifolia. Realizaram-se seis ensaios, sendo para a propagação assexuada: (1) Efeito do diâmetro do caule (8 mm, 11mm e 15mm) em substratos (areia, solo, vermiculita, casca de arroz carbonizada e substrato comercial “Carolina soil®”) e (2) diferentes concentrações de ácido indolbutírico (0; 1500; 3000 mg/L) em distintos tipos de estacas (apical com uma folha inteira, apical com meia folha e subapical). Para a propagação sexuada foram realizados três experimentos: (1) Efeito dos substratos (papel e areia) e quatro temperaturas (20, 25, 30 e 35ºC), (2) três acessos (Peruíbe, Iporanga e Botucatu -SP) e (3) posição da sementes (sobre e entre) em quatro diferentes substratos (papel, areia, vermiculita e substrato comercial), as variáveis avaliadas foram percentual de germinação (G%) e índice de velocidade de germinação (IVG). Para o desenvolvimento inicial e trocas gasosas os tratamentos consistiram em pleno sol, 30%, 50% e 70% de sombreamento e seis épocas de... / The “white fig-tree” (Ficus adhatodifolia Schott Spreng.) is a medicinal species and its latex, awfully used in folk medicine to treat worms, is obtained mainly by extraction, which if it is made indiscriminately, may result in loss of genetic and chemical diversity of the species. Thus, studies about early development are important tools that can ensure greater chances of conservation and maintenance of the species. The present study aimed to investigate the sexual and asexual propagation and determine the effect of different levels of light intensity on the early development and gas exchange of F. adhatodifolia. There were six trials, and for the propagation assexual: (1) Effect of stem diameter (8mm, 11mm and 15mm) on different substrates (sand, soil, vermiculite, rice hulls and commercial substrate) and (2) different concentrations of IBA (0, 1500, 3000 mg / L) in different types of cuttings (apical with a full sheet, half sheet with apical and subapical). For sexual propagation experiments were carried out: (1) Effect of two types of substrates (paper and sand) and four temperatures (20, 25, 30 and 35 º C), (2) three different accessions (Peruíbe, Iporanga and Botucatu-SP) and (3) position of the seeds (on and between) in four different substrates (paper, sand, vermiculite and commercial substrate). The variables studied were seed germination percentage (G%) and germination velocity index (GVI). The experimental design of different levels of light intensity on the early development and gas exchange was randomized blocks in factorial scheme 4x6 (0%, 30%, 50% and 70% of shading) and six sampling times (30, 60, 90, 120, 150 and 180 days). The variables evaluated were leaf area, total dry weight, rate of CO2 assimilation (A), leaf conductance (Gs), transpiration (E), intercellular CO2 concentration (Ci), water... (Complete abstract click electronic access below)
42

Propagação e desenvolvimento inicial defícus adhatodifolia Schott ex Spreng. (Moraceae) em diferentes temperaturas, intensidades luminosas e substratos /

Gonçalves, Gabriela Granghelli, 1985- January 2012 (has links)
Orientador: Lin Chau Ming / Banca: Carmen Silvia Fernandes Boaro / Banca: Lilia Aparecida Salgado de Morais / Resumo: A "figueira branca" (Ficus adhatodifolia Schott ex Spreng.) é uma espécie nativa do Brasil, utilizada na medicina tradicional devido à atividade anti-helmíntica do seu látex e também é recomendada no tratamento de ancilostomose, icterícia e aos seus frutos são atribuídas propriedades afrodisíacas e estimulantes de memória. A principal forma de coleta da espécie é o extrativismo indiscriminado que pode resultar na perda de diversidade genética e química da espécie. Assim, os estudos sobre propagação e desenvolvimento inicial são importantes ferramentas que podem garantir maiores chances de conservação e manutenção da espécie. O presente trabalho teve como objetivo estudar a propagação sexuada e assexuada e verificar o efeito de diferentes níveis de intensidade luminosa no desenvolvimento inicial e trocas gasosas de F. adhatodifolia. Realizaram-se seis ensaios, sendo para a propagação assexuada: (1) Efeito do diâmetro do caule (8 mm, 11mm e 15mm) em substratos (areia, solo, vermiculita, casca de arroz carbonizada e substrato comercial "Carolina soil®") e (2) diferentes concentrações de ácido indolbutírico (0; 1500; 3000 mg/L) em distintos tipos de estacas (apical com uma folha inteira, apical com meia folha e subapical). Para a propagação sexuada foram realizados três experimentos: (1) Efeito dos substratos (papel e areia) e quatro temperaturas (20, 25, 30 e 35ºC), (2) três acessos (Peruíbe, Iporanga e Botucatu -SP) e (3) posição da sementes (sobre e entre) em quatro diferentes substratos (papel, areia, vermiculita e substrato comercial), as variáveis avaliadas foram percentual de germinação (G%) e índice de velocidade de germinação (IVG). Para o desenvolvimento inicial e trocas gasosas os tratamentos consistiram em pleno sol, 30%, 50% e 70% de sombreamento e seis épocas de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The "white fig-tree" (Ficus adhatodifolia Schott Spreng.) is a medicinal species and its latex, awfully used in folk medicine to treat worms, is obtained mainly by extraction, which if it is made indiscriminately, may result in loss of genetic and chemical diversity of the species. Thus, studies about early development are important tools that can ensure greater chances of conservation and maintenance of the species. The present study aimed to investigate the sexual and asexual propagation and determine the effect of different levels of light intensity on the early development and gas exchange of F. adhatodifolia. There were six trials, and for the propagation assexual: (1) Effect of stem diameter (8mm, 11mm and 15mm) on different substrates (sand, soil, vermiculite, rice hulls and commercial substrate) and (2) different concentrations of IBA (0, 1500, 3000 mg / L) in different types of cuttings (apical with a full sheet, half sheet with apical and subapical). For sexual propagation experiments were carried out: (1) Effect of two types of substrates (paper and sand) and four temperatures (20, 25, 30 and 35 º C), (2) three different accessions (Peruíbe, Iporanga and Botucatu-SP) and (3) position of the seeds (on and between) in four different substrates (paper, sand, vermiculite and commercial substrate). The variables studied were seed germination percentage (G%) and germination velocity index (GVI). The experimental design of different levels of light intensity on the early development and gas exchange was randomized blocks in factorial scheme 4x6 (0%, 30%, 50% and 70% of shading) and six sampling times (30, 60, 90, 120, 150 and 180 days). The variables evaluated were leaf area, total dry weight, rate of CO2 assimilation (A), leaf conductance (Gs), transpiration (E), intercellular CO2 concentration (Ci), water... (Complete abstract click electronic access below) / Mestre
43

The interactive effects of light, temperature and CO₂/O₂ ratios in photosynthesis of Coix lachryma-jobi L

Mjwara, Jabulani Michael January 1992 (has links)
A portable infra red gas analyzer was used to investigate the interactive effects of light, temperature, and CO,jO, ratios under controlled environmental conditions in an attempt to model gas exchange characteristics of Coix Iachryma-jobi L. Plotting light response curves as a function of temperature (20, 25 30 and 35°C) revealed no sign of light saturation even at a photosynthetic photon flux density (PPFD) close to 2000 !Lmol m-' sol. High net assimilation rates (A) of approximately 24 !Lmol CO, m"s'! were realized at 30-35°C. Assimilation (A) versus internal CO, partial pressure (C,) curves showed a steep rise with increase in C, but saturated at approximately 150 (JLII-!) and all the results, either in the absence or presence of 0" showed a similar response under all temperature regimes. C. Iachryma-jobi exhibited low CO, compensation points cr ) between 0 and 10 JLlI-! under similar experimental temperatures and either at 0 or 21%0,. The slopes of double reciprocal plots of llA versus llCi, were nearly identical and crossed the yintercept at almost identical points under all 0, concentrations. These data indicate first; that there was no apparent 0, inhibition and second; indicated that the apparent inhIbitor constant (K,) for 0, at the site of carboxylation did not change with increase in [OJ from 0 to 21% oxygen. These observations were further confirmed by results obtained from the analysis of apparent carboxylation efficiency (CE, as defined as the slope of response of A to increasing CO,), as no inhibition of A with increase of [OJ occurred. These characteristics were consistent with typical features of C,photosynthesis. The absence of 0, inhibition and low r values indicated that an efficient CO, concentrating mechanism which eliminates photorespiration exists in C. Iachryma-jobi. At the light microscope level, leaf anatomy exhibited typical C, structure viz. bundle sheath with large chloroplasts and this sheath is further surrounded by a radiate Kranz mesophyU cells. Furthermore the anatomical features suggested that C. wchryma-jobi was an NADP-ME species. Stomatal conductance (g,) to assimilation (g,/A) indicated an increase in A with decrease in g" an essential feature of improving water use efficiency (WUE), but one which drastically reduces CO, diffusion rate. The physical lintitation (stomatal lintitation, t) to CO, diffusion under various [0,] and temperatures, but constant PPFD, did not exhibit statistically significant change in t values at either 0 or 21% a, within each temperature regime, however there was a marked decrease in t as the plant approached its optimum photosynthetic temperature.
44

Caesalpinia pulcherrima, Calliandra californica, and Justicia specigera: Chemical and environmental regulation of their growth and development

Davison, Elizabeth L., 1947-, Davison, Elizabeth L., 1947- January 1989 (has links)
Investigations of three low-water requiring landscape species produced the following results: (1) Although Calliandra californica flowered under photoperiods from 12 to 16 hours, plants produced more elongation under 16 hour days. Plants grew taller and developed greener foliage under irradiances of 600 μmol·m⁻²·s⁻¹. Branching was not stimulated by foliar sprays of BA, PBA, or BA + GA₄₊₇. (2) Caesalpinia pulcherrima increased biomass under 16 hour days, but were stunted and chlorotic under irradiances of 1950 μmol·m⁻²·s⁻¹. Internodal lengths were restricted with drenches of 3.75 mg · pot-1 uniconazole, and plants sprayed with 500 mg·liter⁻¹ PBA developed more axillary branching without negative elongating effects. (3) Justicia specigera gained more height under 12 hour days, and produced greener foliage, more elongation, and faster flowering under irradiances of 600 μmol·m⁻²·s⁻¹. Plants showed restricted internodal elongation and fewer flowers when drenched with 5.0 mg·pot⁻¹ uniconazole, and developed more axillary branching with no detrimental elongation effects when sprayed with 100 mg·liter⁻¹ BA + GA₄₊₇.
45

Influência da luz e temperatura em cavidades e canais secretores em plântulas de Copaifera langsdorffii Desf. (Leguminosae-Caesalpinioideae) : estudo anatômico e ultraestrutural /

Buarque, Plácido Fabrício Silva Melo. January 2013 (has links)
Orientador: Tatiana Maria Rodrigues / Banca: Camila Rozindo Dias Milanez / Banca: Aline Redondo Martins / Resumo Espaços secretores estão distribuídos por todo o eixo vegetativo de Copaifera langsdorffii. São constituídos por epitélio secretor unisseriado e lúmen amplo e, devido à secreção produzida, representam um mecanismo de defesa constitutivo contra herbívoros e patógenos. Nas plântulas desta espécie, cavidades secretoras de óleo ocorrem no mesofilo dos eofilos e no córtex do epicótilo e hipocótilo, enquanto que canais secretores de oleorresina estão presentes na medula do epicótilo e hipocótilo. Evidências sugerem que fatores exógenos podem influenciar na produção da secreção nessa espécie; entretanto, nada se conhece sobre a influência desses fatores no desenvolvimento de canais e cavidades. Este trabalho teve como objetivo investigar a influência da luz e da temperatura na densidade e na área do lúmen de cavidades e canais secretores em plântulas de C. langsdorffii, além de estudar a influência da temperatura na ultraestrutura das células epiteliais. Plântulas foram mantidas em câmara climática sob 2500lux, 1250lux e 250lux e 15ºC, 25ºC e 35ºC. Para análises anatômicas quantitativas, amostras do epicótilo e eofilos foram processadas segundo técnicas usuais em anatomia vegetal. Para análises ultraestruturais, amostras de eofilos foram preparadas de acordo com técnicas convencionais de microscopia eletrônica de transmissão. Plântulas mantidas sob 25ºC/1250lux mostraram maior densidade de cavidades nos eofilos e no epicótilo, enquanto aquelas mantidas sob 25ºC/2500lux apresentaram maior densidade de ... / Abstract Secretory spaces are distributed throughout the vegetative axis of Copaifera langsdorffii. They are constituted by uniseriate secretory epithelium and wide lumen, and represent a constitutive defense mechanism against herbivores and pathogens due to the produced secretion. In C. langsdorffii seedlings, oil cavities occur in the mesophyll of eophylls and in the cortex of epicotyl and hypocotyl, whereas oleoresin canals are present in the pith of epicotyl and hypocotyl. Evidences suggest that exogenous factors can influence the production of secretion in this species; however, nothing is known about these factors influencing the development of canals and cavities. This work aimed to investigate the influence of light and temperature on the density and lumen area of secretory canals and cavities in seedlings of C. langsdorffii, besides to study the influence of the temperature on the ultrastructural features of epithelial cells. Seedlings were maintained in climatic chamber under 2500lux, 1250lux and 250lux, and 15ºC, 25ºC and 35ºC. For quantitative anatomical analysis, samples of epicotyl and eophylls were processed according to usual techniques in plant anatomy. For ultrastructural studies, samples of eophylls were prepared following conventional techniques of transmission electron microscopy. Seedlings under 25ºC/1250lux presented higher density of cavities in eophylls and epicotyl, whereas seedlings under 25ºC/2500lux showed higher density of canals. This differential answer to light can be related to the distinctive origin of these secretory structures. Concerning the lumen area, variable answers were observed to cavities and canals. Ultrastructurally, epithelial cells of seedlings under 25ºC showed evidences of intense secretory activity. Alterations in mitochondria, plastids and endoplasmic reticulum were observed in seedlings under 15ºC and 35ºC. In seedlings under 35ºC, the epithelial cells showed evident signals of lysis, ... / Mestre
46

Influence of light on algal growth in the lower Willamette River

Wille, Stephen Arthur 01 January 1976 (has links)
During the summer of 1974 chemical conditions in the lower reaches of the Willamette River, Oregon were similar to those in other rivers currently experiencing nuisance algal growth problems. Temperature and chemical nutrients are not limiting. Relatively high populations of phytoplankton and productivity values for upstream periphyton beds and surface waters suggest moderately eutrophic conditions. However, with increased depth in the lower river, and a constant euphotic zone, the amount of photosynthetically available light is reduced. With sufficient depth and complete mixing the critical depth is exceeded. Primary productivity rates are subsequently limited by low light availability in the lower river.
47

Effects of light and temperature on the formation of sexual structures in the family Saprolegniaceae

Lee, Philip C. January 1965 (has links)
Pure cultures of Saprolegnia ferax (Gruith) Thuret, Achlya americana Humphrey, and two isolates of Saprolegnia parasitica Coker were grown in a chemically defined medium under controlled conditions of temperature and illumination. Light inhibited growth and oogonium formation rates in S. ferax and A. americana. Light inhibited zoospore germination rates in A. americana and the growth rate of S. parasitica isolate 2-27-59; S. parasitica isolate 6-28-60 was indifferent to light. Neither isolate of S. parasitica formed sexual structures during the experiments. Differences in light reactions and growth rates of these two isolates indicated physiological strain differences. Photoreactivation was demonstrated in S. ferax and both isolates of S. parasitica. Evidence was shown that light caused production of toxic substances in the medium which caused inhibition of growth and sporulation. The blue peroxychromic test for hydrogen peroxide in the medium was negative but apparent catalase activity was demonstrated. Using a simple medium consisting of glucose, soluble starch and yeast extract, white light stimulated vegetative growth in S. ferax and A. americana. A quantitative distribution pattern of oogonium formation was shown. / Ph. D.
48

Temperature and photoperiod effects on growth and development of day-neutral, junebearing and everbearing strawberries

Durner, Edward Francis January 1982 (has links)
Responses of day-neutral (DN) strawberries (Fragaria X ananassa Duch.) to photoperiod and temperature under controlled environment conditions were studied and compared to those of Junebearers (JB) and everbearers (EB). At a constant 21°C, DN cultivars flowered under 9 hour days (SD), night interrupted SD (NI) and 16 hour days (LD). Runner production occurred under NI and LD but not SD. Net photosynthesis (Pn) expressed on a leaf area basis, tended to be higher for DN than JB or EB. Pn on a whole plant basis, was greater under NI than SD due to increased leaf area under NI. Pn under LD was not considered. Under fluctuating temperatures (18°/14°, 22°/18°, 26°/22° or 30°/26° C day/night combinations), responses to SD and NI varied. At 18/14, DN cultivars flowered under either NI or SD. At 22/18 and 26/22, flowering was greater under NI than SD. At 30/26, flowering did not occur. At 18/14, 22/18, or 30/26, runner production was unaffected by photoperiod and occurred under NI and SD. At 26/22, runner production was enhanced by NI compared to SD. Data for the Junebearers and everbearers is also presented and discussed. / Master of Science
49

Seasonal changes in specific leaf weight and leaf anatomy of apple

Wooge, Jon Dayton January 1983 (has links)
The position of newly expanded shoot leaves in the canopy of apple trees had significant and similar effects on specific leaf weight (SLW), leaf thickness, length of palisade tissue, and number of cell layers in the palisade tissue. Inside canopy leaves had lower SLW, leaf thickness, palisade length, and number of palisade cell layers than middle and outside leaves at each of six sample dates ranging from late May to early October. Outside canopy leaves had the highest values at all sample dates. Differences in SLW, leaf thickness, and palisade length between inside and outside leaves increased as the season progressed, primarily due to a general increasing trend in outside leaves that developed later in the season. Effects of canopy position on spur leaves were not as great as with shoot leaves. Regression analysis showed SLW to be significantly correlated with leaf thickness and palisade length. / M.S.
50

Floral initiation in <i>Rudbeckia hirta</i>: limited inductive photoperiod, polyamines and cytokinins

Harkess, Richard Lee 06 June 2008 (has links)
This study examined floral initiation in Rudbeckia hirta at the biochemical, cellular, and whole plant levels. Histological and histochemical examination of floral initiation revealed that the pattern of initiation followed closely that described in other species. The primary difference was in the length of time over which initiation and differentiation occurred. When subjected to limited inductive photoperiods, R. hirta responded with a delay in flowering if the plants were returned to short days (SD) before bract initiation. Increased exposure to long days (LD) increased stem height and enhanced floral development. A limited induction period of at least 8 LD allowed enough of the floral stimulus to be translocated to the meristem to cause no interruption in development even upon return to non-inductive conditions. An inhibition of development occurred only when plants were returned to SD before periclinal divisions in the pith rib meristem commenced after approximately 8 LD. Axillary bud development and final plant height were dependent on the number of inductive LD received. Polyamines have been linked to floral initiation and, in this study, were strongly correlated to the stage of floral initiation. As initiation progressed, the observed increases in putrescine and spermidine were followed by a decrease after 16 LD, the observed onset of floral development. This was contrary to that previously observed in SD plants but followed a pattern similar to that reported for cytokinin behavior. Exogenous cytokinins have been used to stimulate floral initiation in several species but Rudbeckia hirta did not respond to benzyladenine (BA) applied at the onset of LD. Floral initiation has been found to begin after six to eight LD and, in most species, BA was most effective when applied during initiation. In an attempt to increase uptake, BA was dissolved in dimethyl sulfoxide (DMSO). This did not enhance the effects of BA and, in fact, DMSO was found to be toxic at concentrations of 25% or more. / Ph. D.

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