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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.
1

Botanical inventory and phenology in relation to foraging behaviour of the Cape honeybees (Apis mellifera capensis) at a site in the Eastern Cape, South Africa

Merti, Admassu Addi. January 2003 (has links)
Thesis (M.S.)--Rhodes University, 2003. / Title from PDF t.p. (viewed on June 9, 2006). Includes bibliographical references (p. 110-122).
2

Genetic variation and phenotypic stability among three elevational sources of coastal Douglas-fir from southwest Oregon /

Mangold, Robert. January 1987 (has links)
Thesis (Ph. D.)--Oregon State University, 1988. / Typescript (photocopy). Includes bibliographical references (leaves 97-102). Also available on the World Wide Web.
3

Ácido salicílico na qualidade pós-colheita de frutos, hortaliças folhosas e flores

Borsatti, Fabiana Chiamulera 27 February 2014 (has links)
O objetivo deste trabalho foi avaliar o efeito do ácido salicílico (AS) aplicado em pós-colheita de amora-preta, acerola, couve manteiga, espinafre e rosas sobre a conservação e a indução de resistência. O delineamento experimental foi inteiramente ao acaso, com quatro repetições e os tratamentos foram baseados nas concentrações das soluções com AS 0,0; 0,5; 1,0; 1,5; e 2,0 mM. As culturas foram imersas nas soluções com os diferentes tratamentos e após armazenadas a 8°C. Para as frutas (amora-preta e acerola) as avaliações realizadas foram perda de massa da matéria fresca, teores de sólidos solúveis totais (SST), acidez titulável (AT), ácido ascórbico e incidência de podridões. Nos intervalos de 24, 48, 96 e 192 horas após a aplicação dos tratamentos, retirou-se amostras de frutos para determinação de proteínas totais, antocianinas, flavonóides e atividade das enzimas fenilalanina amônia-liase (FAL), quitinases e β-1,3-glucanase. Tais análises foram realizadas para todos os tratamentos, com exceção de quitinase e β-1,3-glucanase, sendo estas avaliações feitas somente para frutos tratados com 2,0 mM e a testemunha. Para as hortaliças (couve manteiga e espinafre) as avaliações foram perda de massa da matéria fresca, podridões, teor de vitamina C e clorofilas. Em intervalos de 24, 48, 96 e 192 horas após a aplicação dos tratamentos, determinou-se o teor de proteínas, fenóis totais, atividade da FAL e peroxidases. Para as rosas foram realizadas análises visuais de curvatura do pedúnculo, turgescência e escurecimento de pétalas. Ao final do experimento, avaliaram-se a perda de massa da matéria fresca, e teor de clorofilas nas folhas. Com intervalos de 24 horas, retirou-se uma amostra das pétalas para determinação de proteínas totais e atividade da FAL e peroxidases. Para amoras-pretas houve aumento do teor de proteínas e ativação da β-1,3-glucanase com a aplicação de AS. Os teores de antocianinas e flavonóides e a atividade da FAL, tiveram alterações no decorrer do experimento em função da aplicação de AS. Os tratamentos não foram significativos para perda de massa da matéria fresca, AT, SST, incidência de podridões, ácido ascórbico e atividade de quitinase para essa fruta. Para acerolas, a AT foi maior e os SST foram menores naquelas tratadas com AS. Os tratamentos não foram significativos para perda de massa da matéria fresca e ácido ascórbico de acerola. Houve redução da incidência de podridões em frutos com aplicação de AS, ativação das enzimas quitinases, β-1,3-glucanase e FAL e, aumento nos teores de antocianinas e flavonoides para acerola. Para couve manteiga a aplicação de AS manteve os teores de proteínas e fenóis totais em níveis mais elevados, e interferiu na atividade das peroxidases. Não houve significância para perda de massa da matéria fresca, teor de vitamina C, clorofilas, podridões e atividade de FAL. Para espinafre as maiores concentrações de AS diminuíram a perda de massa da matéria fresca e mantiveram os teores de proteínas mais elevados. Os tratamentos não interferiram no teor de clorofilas, fenóis totais, e atividade da peroxidases e FAL. Houve efeito nos teores de proteína totais, atividade da FAL e peroxidase nas hastes das rosas com a aplicação de solução contendo AS. As rosas tratadas com a maior concentração de AS mantiveram-se com as notas mais elevadas para curvatura de haste, turgescência e escurecimento de pétalas, ou seja, com melhor aspecto visual. / The aim of this work was to evaluate the salicylic acid (SA) effect applied in the blackberry, acerola, kale, spinach and roses postharvest for the conservation and resistance induction. The experimental design was completely randomized, with four replications and the treatments were based on the solutions concentrations with SA 0.0, 0.5, 1.0, 1.5 and 2.0 mM. The vegetable organs from the cultures were immersed in the solutions with different treatments and after it was stored at 8 °C. For the fruit (blackberry and acerola) the fresh matter weight losses, total soluble solids (TSS), titratable acidity (TA), ascorbic acid and rot incidence were evaluated. During the intervals of 24, 48, 96 and 192 hours after treatment application, fruit samples were separated for total protein, anthocyanins, flavonoids and phenylalanine ammonia lyase (PAL), chitinase and β-1,3-glucanase enzymes activities were determinate. These analyzes were applied for all treatments, with the exception of chitinase and β-1,3-glucanase, which were evaluated only for fruits treated with 2.0 mM concentration and control treatment. For the vegetables (kale and spinach) the fresh mass losses, rot incidence, vitamin C and chlorophyll were evaluated. During the intervals of 24, 48, 96 and 192 hours after treatment application, the total protein, total phenols, phenylalanine ammonia lyase (PAL) and peroxidase enzimes were evaluated. For roses the peduncle curvature, turgescence and petals darkening were visual evaluated. When the experiment time finished, the fresh weight losses and the leaf chlorophyll content were evaluated. During 24 hour intervals, collected a petals sample to determine the total protein and PAL and peroxidase activities. For blackberries there was an increase of protein level and the β-1,3-glucanase activation with the application of SA. The anthocyanins and flavonoids contents and the PAL activity, had changes during the experiment due to the SA application. The treatments were not significant for fresh mass losses, TA, TSS, rot incidence, ascorbic acid and chitinase activities for this fruit. In the acerola, the TA was higher and TSS were lower in the fruit treated with SA. The treatments were not significant for fresh mass losses, of ascorbic acid content. There was a reduction in the fruit rots incidence with application of SA and an activation of chitinase, β-1,3-glucanase and PAL activity enzymes, and it increased anthocyanins and flavonoids contents for acerola. The SA application in the kale kept the protein and total phenol with higher levels and it interfere in the peroxidases activity. There was no significant treatment effect for fresh weight losses, vitamin C, chlorophyll, rot incidence and PAL activity. The highest SA concentrations decreased the fresh weight losses and they kept the higher proteins contents for spinach. The treatments did not affect the chlorophyll content, total phenolics and peroxidase and PAL activities.There wasn't treatment effect about total protein content, PAL and peroxidase activity in the roses stems. The rose treated with the highest SA concentration presented higher grade evaluation for peduncle curvature, turgescence and petals darkening, ie, the best visual aspect.
4

Ácido salicílico na qualidade pós-colheita de frutos, hortaliças folhosas e flores

Borsatti, Fabiana Chiamulera 27 February 2014 (has links)
O objetivo deste trabalho foi avaliar o efeito do ácido salicílico (AS) aplicado em pós-colheita de amora-preta, acerola, couve manteiga, espinafre e rosas sobre a conservação e a indução de resistência. O delineamento experimental foi inteiramente ao acaso, com quatro repetições e os tratamentos foram baseados nas concentrações das soluções com AS 0,0; 0,5; 1,0; 1,5; e 2,0 mM. As culturas foram imersas nas soluções com os diferentes tratamentos e após armazenadas a 8°C. Para as frutas (amora-preta e acerola) as avaliações realizadas foram perda de massa da matéria fresca, teores de sólidos solúveis totais (SST), acidez titulável (AT), ácido ascórbico e incidência de podridões. Nos intervalos de 24, 48, 96 e 192 horas após a aplicação dos tratamentos, retirou-se amostras de frutos para determinação de proteínas totais, antocianinas, flavonóides e atividade das enzimas fenilalanina amônia-liase (FAL), quitinases e β-1,3-glucanase. Tais análises foram realizadas para todos os tratamentos, com exceção de quitinase e β-1,3-glucanase, sendo estas avaliações feitas somente para frutos tratados com 2,0 mM e a testemunha. Para as hortaliças (couve manteiga e espinafre) as avaliações foram perda de massa da matéria fresca, podridões, teor de vitamina C e clorofilas. Em intervalos de 24, 48, 96 e 192 horas após a aplicação dos tratamentos, determinou-se o teor de proteínas, fenóis totais, atividade da FAL e peroxidases. Para as rosas foram realizadas análises visuais de curvatura do pedúnculo, turgescência e escurecimento de pétalas. Ao final do experimento, avaliaram-se a perda de massa da matéria fresca, e teor de clorofilas nas folhas. Com intervalos de 24 horas, retirou-se uma amostra das pétalas para determinação de proteínas totais e atividade da FAL e peroxidases. Para amoras-pretas houve aumento do teor de proteínas e ativação da β-1,3-glucanase com a aplicação de AS. Os teores de antocianinas e flavonóides e a atividade da FAL, tiveram alterações no decorrer do experimento em função da aplicação de AS. Os tratamentos não foram significativos para perda de massa da matéria fresca, AT, SST, incidência de podridões, ácido ascórbico e atividade de quitinase para essa fruta. Para acerolas, a AT foi maior e os SST foram menores naquelas tratadas com AS. Os tratamentos não foram significativos para perda de massa da matéria fresca e ácido ascórbico de acerola. Houve redução da incidência de podridões em frutos com aplicação de AS, ativação das enzimas quitinases, β-1,3-glucanase e FAL e, aumento nos teores de antocianinas e flavonoides para acerola. Para couve manteiga a aplicação de AS manteve os teores de proteínas e fenóis totais em níveis mais elevados, e interferiu na atividade das peroxidases. Não houve significância para perda de massa da matéria fresca, teor de vitamina C, clorofilas, podridões e atividade de FAL. Para espinafre as maiores concentrações de AS diminuíram a perda de massa da matéria fresca e mantiveram os teores de proteínas mais elevados. Os tratamentos não interferiram no teor de clorofilas, fenóis totais, e atividade da peroxidases e FAL. Houve efeito nos teores de proteína totais, atividade da FAL e peroxidase nas hastes das rosas com a aplicação de solução contendo AS. As rosas tratadas com a maior concentração de AS mantiveram-se com as notas mais elevadas para curvatura de haste, turgescência e escurecimento de pétalas, ou seja, com melhor aspecto visual. / The aim of this work was to evaluate the salicylic acid (SA) effect applied in the blackberry, acerola, kale, spinach and roses postharvest for the conservation and resistance induction. The experimental design was completely randomized, with four replications and the treatments were based on the solutions concentrations with SA 0.0, 0.5, 1.0, 1.5 and 2.0 mM. The vegetable organs from the cultures were immersed in the solutions with different treatments and after it was stored at 8 °C. For the fruit (blackberry and acerola) the fresh matter weight losses, total soluble solids (TSS), titratable acidity (TA), ascorbic acid and rot incidence were evaluated. During the intervals of 24, 48, 96 and 192 hours after treatment application, fruit samples were separated for total protein, anthocyanins, flavonoids and phenylalanine ammonia lyase (PAL), chitinase and β-1,3-glucanase enzymes activities were determinate. These analyzes were applied for all treatments, with the exception of chitinase and β-1,3-glucanase, which were evaluated only for fruits treated with 2.0 mM concentration and control treatment. For the vegetables (kale and spinach) the fresh mass losses, rot incidence, vitamin C and chlorophyll were evaluated. During the intervals of 24, 48, 96 and 192 hours after treatment application, the total protein, total phenols, phenylalanine ammonia lyase (PAL) and peroxidase enzimes were evaluated. For roses the peduncle curvature, turgescence and petals darkening were visual evaluated. When the experiment time finished, the fresh weight losses and the leaf chlorophyll content were evaluated. During 24 hour intervals, collected a petals sample to determine the total protein and PAL and peroxidase activities. For blackberries there was an increase of protein level and the β-1,3-glucanase activation with the application of SA. The anthocyanins and flavonoids contents and the PAL activity, had changes during the experiment due to the SA application. The treatments were not significant for fresh mass losses, TA, TSS, rot incidence, ascorbic acid and chitinase activities for this fruit. In the acerola, the TA was higher and TSS were lower in the fruit treated with SA. The treatments were not significant for fresh mass losses, of ascorbic acid content. There was a reduction in the fruit rots incidence with application of SA and an activation of chitinase, β-1,3-glucanase and PAL activity enzymes, and it increased anthocyanins and flavonoids contents for acerola. The SA application in the kale kept the protein and total phenol with higher levels and it interfere in the peroxidases activity. There was no significant treatment effect for fresh weight losses, vitamin C, chlorophyll, rot incidence and PAL activity. The highest SA concentrations decreased the fresh weight losses and they kept the higher proteins contents for spinach. The treatments did not affect the chlorophyll content, total phenolics and peroxidase and PAL activities.There wasn't treatment effect about total protein content, PAL and peroxidase activity in the roses stems. The rose treated with the highest SA concentration presented higher grade evaluation for peduncle curvature, turgescence and petals darkening, ie, the best visual aspect.
5

Frugivoria e germinação de sementes após passagem pelo sistema digestivo de masupiais em floresta estacional semidecidual

Leiva, Maristela [UNESP] 09 April 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-09Bitstream added on 2014-06-13T20:16:47Z : No. of bitstreams: 1 leiva_m_me_botib.pdf: 524607 bytes, checksum: 6be14091f581fd60f9bd4d9666b997c7 (MD5) / A dispersão de sementes é uma parte essencial da biologia reprodutiva das plantas, na qual a zoocoria é a principal forma de dispersão em florestas tropicais. Isto revela sua extrema importância para a regeneração e manutenção das florestas, sendo que os marsupiais podem agir como dispersores efetivos de plantas neotropicais através da ingestão de sementes. O objetivo deste estudo foi determinar as espécies de marsupiais ocorrentes e as espécies de plantas utilizadas como recurso em um fragmento de Floresta Estacional Semidecidual, localizado nos arredores do município de Botucatu, SP. O presente estudo também objetivou estudar a viabilidade e o comportamento germinativo das sementes após a passagem pelo sistema digestivo destes animais. Os marsupiais foram capturados de agosto de 2008 a julho de 2009 com armadilhas do tipo alçapão e de interceptação e queda. Suas fezes foram coletadas diretamente das armadilhas, durante o manuseio do animal ou ainda após a manutenção em cativeiro por 24 horas. Depois as amostras fecais foram triadas em laboratório. Foram realizados testes de germinação de sementes com dois tratamentos: (1) sementes retiradas das fezes e (2) sementes retiradas dos frutos maduros. O teste de tetrazólio foi aplicado para verificar a viabilidade das sementes de Piper amalago que não germinaram. Foi caracterizada a fenologia reprodutiva de 14 espécies vegetais utilizadas pelos marsupiais, sendo que quatro estavam presentes nas fezes. O período de maior disponibilidade de frutos prevaleceu dentro da estação chuvosa. Foram encontradas 11 espécies vegetais presentes nas amostras fecais dos marsupiais, sendo parte de plantas pioneiras. O marsupial Didelphis albiventris foi a espécie mais abundante e os frutos mais consumidos por ele foram as piperáceas: Piper hispidinervum (36% das amostras), seguido de Piper aduncum (19%) e Piper amalago (17%)... / Seed dispersal is an essential stage on plant reproductive biology, and zoochory is the main process of dispersion in tropical rain forests. Therefore, seed dispersal is very important to forest conservation and regeneration, and the marsupials may act as seed dispersers of neotropical plants by ingesting seeds. The main goal of this study was to determine the marsupial species as well as their food plants occurring in a semi-deciduous seasonal forest fragment located near the city of Botucatu, SP. This study also investigated seed viability and germination after passage through the marsupial guts. The animals were collected from August to July 2008 by using live and pitfall traps. Their feces were collected from traps, during animal handling or when the animals were kept in captivity for 24 hours. In the laboratory, seeds were removed from feces. Germination tests were carried out following two treatments: (1) seeds from feces and (2) seeds removed from mature fruits. The tetrazolium test was applied on nongerminated seeds of Piper amalago to determine their viability. The reproductive phenology of 14 plant species used by marsupials was also recorded, from which four were observed in the marsupial’s feces. Most fruits were available to the marsupials during the rainy season. A total of 11 plant species were found in the feces samples, and some of them was consisted of pioneering plants. Didelphis albiventris was the predominant marsupial species, and fruits of Piper hispidinervum (36%), Piper aduncum (19%) and Piper amalago plants (17%) were preferably consumed. The germination tests were carried out considering those plant species with high abundances on feces: P. aduncum, P. amalago, P. hispidinervum and Psidium guajava. The passage of P. amalago, P. aduncum and P. guajava seeds through the D. albiventris gut did not change the germination percentage when comparing with... (Complete abstract click electronic access below)
6

Temporal Synchrony between Ground-Nesting Bees and Spring Ephemerals in an Eastern Hardwood Forest Ecosystem

Sevenello Montagner, Jose Manuel 17 October 2018 (has links)
Changes in phenology due to climate warming could disrupt temporal overlap between interacting organisms when previously synchronized species respond to climate change at different rates. Phenologies of plants and insects are known to be sensitive to temperature and/or timing of snowmelt, with warmer temperatures and earlier snowmelt generally advancing spring flowering and emergence; however, some groups of pollinators, such as solitary bees, have been little explored in this context. One striking aspect of eastern hardwood forests is the emergence of understory wildflowers each spring, most of which rely, at least to some extent, on wild native pollinators for seed set. Without an understanding of the environmental drivers of phenology of these species, we have little ability to predict whether pollinators will continue to be well synchronized with flowering as the climate changes. In this study, I determined how spring temperatures and timing of snowmelt influence the phenology of spring wildflowers, activity of bees, and their temporal overlap in Gatineau Park, Québec. From 2013 to 2018, I characterized bee activity phenology and flowering phenology of understory plants in multiple study plots, focusing on early-flowering Anemone spp. and later-flowering Trillium grandiflorum. The sampled bee community was dominated by Andrena, Lasioglossum, and Nomada, all of which have similar activity periods. Degree-day accumulation was a better predictor of Anemone and Nomada phenology than were day of year or snowmelt date, whereas T. grandiflorum appeared to be more sensitive to photoperiodic cues; since day of year was the variable that best described its phenology. Activity periods of Andrena and Lasioglossum were equally well described by degree-day accumulation and by day of year. No taxon’s phenology was best predicted by snowmelt date. Despite these differences among taxa in the identities of the best predictors of phenology, bee activity and plant flowering phenologies responded at similar rates to interannual and among-site variation in snowmelt date and early spring temperature. Temporal overlap between flowering and bee activity was similar over the years of this study and was affected neither by snowmelt date nor by temperature. These results suggest that interacting plant and bee taxa may respond to different environmental variables but still maintain their synchrony under the conditions recorded so far.
7

Brassica tournefortii phenology, interactions and management of an invasive mustard /

Marushia, Robin Gene. January 2009 (has links)
Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Title from first page of PDF file (viewed Febrary 1, 2010). Includes bibliographical references (p. 140-143). Issued in print and online. Available via ProQuest Digital Dissertations.
8

An evaluation of the relative value of spectral and phenological information for tree crown classification of digital images in the eastern deciduous forest /

Key, Thomas Lee. January 1998 (has links)
Thesis (M.A.)--West Virginia University, 1998. / Title from document title page. Document formatted into pages; contains viii, 51 p. : col. ill., col. map. Vita. Includes abstract. Includes bibliographical references (p. 32-34).
9

The influence of distance and floral phenology on pollen gene flow and mating system patterns in a coastal Douglas-fir seed orchard /

Erickson, Vicky J., January 1987 (has links)
Thesis (M.S.)--Oregon State University, 1988. / Typescript (photocopy). Includes bibliographical references (leaves 69-74). Also available on the World Wide Web.
10

Frugivoria e germinação de sementes após passagem pelo sistema digestivo de masupiais em floresta estacional semidecidual /

Leiva, Maristela. January 2010 (has links)
Resumo: A dispersão de sementes é uma parte essencial da biologia reprodutiva das plantas, na qual a zoocoria é a principal forma de dispersão em florestas tropicais. Isto revela sua extrema importância para a regeneração e manutenção das florestas, sendo que os marsupiais podem agir como dispersores efetivos de plantas neotropicais através da ingestão de sementes. O objetivo deste estudo foi determinar as espécies de marsupiais ocorrentes e as espécies de plantas utilizadas como recurso em um fragmento de Floresta Estacional Semidecidual, localizado nos arredores do município de Botucatu, SP. O presente estudo também objetivou estudar a viabilidade e o comportamento germinativo das sementes após a passagem pelo sistema digestivo destes animais. Os marsupiais foram capturados de agosto de 2008 a julho de 2009 com armadilhas do tipo alçapão e de interceptação e queda. Suas fezes foram coletadas diretamente das armadilhas, durante o manuseio do animal ou ainda após a manutenção em cativeiro por 24 horas. Depois as amostras fecais foram triadas em laboratório. Foram realizados testes de germinação de sementes com dois tratamentos: (1) sementes retiradas das fezes e (2) sementes retiradas dos frutos maduros. O teste de tetrazólio foi aplicado para verificar a viabilidade das sementes de Piper amalago que não germinaram. Foi caracterizada a fenologia reprodutiva de 14 espécies vegetais utilizadas pelos marsupiais, sendo que quatro estavam presentes nas fezes. O período de maior disponibilidade de frutos prevaleceu dentro da estação chuvosa. Foram encontradas 11 espécies vegetais presentes nas amostras fecais dos marsupiais, sendo parte de plantas pioneiras. O marsupial Didelphis albiventris foi a espécie mais abundante e os frutos mais consumidos por ele foram as piperáceas: Piper hispidinervum (36% das amostras), seguido de Piper aduncum (19%) e Piper amalago (17%) ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Seed dispersal is an essential stage on plant reproductive biology, and zoochory is the main process of dispersion in tropical rain forests. Therefore, seed dispersal is very important to forest conservation and regeneration, and the marsupials may act as seed dispersers of neotropical plants by ingesting seeds. The main goal of this study was to determine the marsupial species as well as their food plants occurring in a semi-deciduous seasonal forest fragment located near the city of Botucatu, SP. This study also investigated seed viability and germination after passage through the marsupial guts. The animals were collected from August to July 2008 by using live and pitfall traps. Their feces were collected from traps, during animal handling or when the animals were kept in captivity for 24 hours. In the laboratory, seeds were removed from feces. Germination tests were carried out following two treatments: (1) seeds from feces and (2) seeds removed from mature fruits. The tetrazolium test was applied on nongerminated seeds of Piper amalago to determine their viability. The reproductive phenology of 14 plant species used by marsupials was also recorded, from which four were observed in the marsupial's feces. Most fruits were available to the marsupials during the rainy season. A total of 11 plant species were found in the feces samples, and some of them was consisted of pioneering plants. Didelphis albiventris was the predominant marsupial species, and fruits of Piper hispidinervum (36%), Piper aduncum (19%) and Piper amalago plants (17%) were preferably consumed. The germination tests were carried out considering those plant species with high abundances on feces: P. aduncum, P. amalago, P. hispidinervum and Psidium guajava. The passage of P. amalago, P. aduncum and P. guajava seeds through the D. albiventris gut did not change the germination percentage when comparing with... (Complete abstract click electronic access below) / Orientador: Marcelo Nogueira Rossi / Coorientador: Renata Cristina Batista Fonseca / Banca: Cinthia Aguirre Brasileiro / Banca: Gledson Vigiano Bianconi / Mestre

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