Thesis (M.A.)--Ohio University, August, 2004. / Includes bibliographical references (p. 52-54)

Thesis (Ph. D.)--Cornell University, 1929. / eContent provider-neutral record in process. Description based on print version record. Bibliography: p. 123-139.

Thesis (M.S.)--University of Wisconsin--Madison, 1970. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Chicago, Dept. of Ecology and Evolution, December 2002. / Includes bibliographical references. Also available on the Internet.

Thesis (M.A.)--Ohio University, August, 2004. / Title from PDF t.p. Includes bibliographical references (p. 52-54)

Thesis (M.S.)--University of North Texas, May, 2007. / Title from title page display. Includes bibliographical references.

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.

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.

Dissertation submitted in part compliance with the requirements for the Master's Degree in Technology: Homeopathy, Technikon Natal, Durban, South Africa, 2002. / The purpose of this study was to expand on the foundations laid by previous homeopathic research, using controlled agricultural experiments as an objective disease system. More specifically, these trials were to investigate and evaluate the efficacy of a fungicide (Previcur') against homeopathic preparations of a plant pathogenic fungus, Pythium, on seedlings infected with this fungus. Pythium is a worldwide problem and continues to cause substantial crop losses. Few chemical methods are available to control this disease and alternatives are being sought which are more cost-effective, safer for the environment and do not lead to pathogenic resistance. Relatively few trials using Homeopathy in plant pathology have been done to date. Furthermore, many of the earlier trials proved to have little scientific credibility, due to poor methods and insufficient data. More recent trials have shown interesting results, which have opened the doors for further investigation. This study compared the effects of Previcur\xAEagainst Homeopathic preparations of Pythium, on infected cabbage and cucumber seedlings. There were 28 trays for each crop and seven treatments per crop: four Homeopathic treatments (9CH, 15CH, 30CH and 200CH), two controls (one inoculated and the other un-inoculated) and Previcur'. The seedlings were treated twice weekly, using a 2.5ml drench per seedling, and were harvested three weeks after planting. The trial was run twice, in succession. Based on the nature of Pythium and the disease it causes, four parameters were measured in this trial. To assess the germination rate, the seedlings were counted three days after planting, to establish how many had broken the surface soil. To assess survival rate, the seedlings were counted at the time of harvesting. To assess growth, the seedlings were initially weighed wet (immediately after harvesting) and then dry (after 24 hours in an oven at 50\xB0C). The data was analysed by two methods: the General Linear Models Procedure (GLMP) produced ANOVA tables, which compared the variation between the four replicates of each of the seven treatments. The data was also analysed with the Student Newman Keuls (SNK) test, to determine the variation between the seven treatments. The results showed that Previcur®consistently produced the best or second best results, in terms of mean wet and dry weights, which was evident in the statistical analysis. However, a noticeable trend emerged with the 30CH treatment: it provided the lowest mean weights in seven of the eight parameters measured while showing evidence of consistent statistical significance from the other treatments throughout both trials. The implications were that this treatment had either enhanced the disease process or had suppressed plant growth. Student Newman Keuls (SNK) test, to determine the variation between the seven treatments. This trial raised issues regarding the effects of homeopathy on disease, as well as the internal mechanisms of disease control within plant structures. Further research into this area is encouraged, to further the platform already laid by statistically valid trials done thus far. / M

A major concern in contemporary ecology has been the failure of management in many economically and socially important renewable resource systems. In spite of efforts to the contrary, management has often witnessed the evolution of such systems into behavior patterns almost diametrically opposed to their original objectives. Actually, it is management intervention which often seems to have initiated this evolution by disturbing the system's stability properties. This study shows how an alternative approach which emphasizes system redesign may alleviate the .problem of changing stability properties in some relatively simple and well studied ecosystems: the cereal rusts and the crops which they attack. The plant disease epidemiological literature records a number, of ideas about the behavior and management of cereal rust systems. Many of these ideas have been neither adequately field tested nor developed in a coherent analytic framework. In this study mathematical methods are used to determine the logical consequences of some of these hypotheses. The analysis suggests that cereal rust systems might indeed be redesigned to help management meet its objectives. Four alternative and mutually compatible potential strategies for achieving this goal are considered: (1) using natural enemies to delay disease onset, (2) using multilines or variety mixtures to inhibit plant to plant dispersal, (3) changing field geometry to increase dispersal wastage, and (4) employing polygenic resistance to slow the growth rate of the best adapted races. The research and development required to implement any of these strategies is briefly discussed. Recommendations for future work and comments on the promise of plant epidemiology as an area for ecological research are provided. / Science, Faculty of / Zoology, Department of / Graduate