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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.
61

Estudos anatômicos e fisiológicos da organogênese in vitro em Passiflora cincinnata MAST. / Anatomical and physiological studies of organogenesis in vitro of Passiflora cincinnata MAST.

Lombardi, Simone Pacheco 23 January 2004 (has links)
O avanço da cultura do maracujazeiro no país impulsionado pela agroindústria de suco e a crescente demanda de fruta fresca, acarretou o surgimento de problemas, principalmente de ordem fitossanitária, doenças causadas por fungos, bactérias e vírus. A espécie Passiflora cincinnata Mast. por apresentar resistência à doença da parte aérea causada pela ba ctéria Xanthomonas campestris f. sp. passiflorae e, potencial para a comercialização constitui um genótipo de interesse em programas de melhoramento. Visto que a cultura de tecidos tem sido ferramenta importante nesses programas, o presente projeto visa o estudo aspectos anatômicos e fisiológicos da organogênese in vitro dessa espécie. Os explantes utilizados: segmentos radiculares, discos foliares e a própria plântula, obtidos da germinação de sementes in vitro, foram inoculados em meio contendo diferentes concentrações de 6-BA (6-benziladenina) e acrescido de 5% de água de coco, a fim de estabelecer os protocolos de regeneração de plantas in vitro. A concentração de 0,5 mg.L -1 de 6-BA foi a mais adequada para os três explantes, porém, o tempo e a via (direta/indireta) de formação da gema diferiu para cada tipo de explante. Os eventos histológicos que levaram a formação de um novo órgão, via meristemóides (centros meristemáticos) foram descritos. Nos discos foliares a origem foi indireta, com formação de calo a partir das células subepidérmicas das camadas de parênquima clorofiliano. Nos segmentos de raiz e nas raízes das plântulas, a organogênese direta apresentou duas origens, a partir do periciclo, nas raízes com início da estrutura secundária, e a partir do câmbio vascular, nas raízes com estrutura secundária já estabelecida. Também nos segmentos de raiz observou-se a via indireta, esta a partir da proliferação do periciclo. / The progress of passionfruit culture in the country stimulated by the juice agroindustry and due to an increased demand of fresh fruit have brought phytosanitary problems, such as, diseases caused by fungis, bacterium and virus. The Passiflora cincinnata Mast. a resistant specie to Xanthomonas campestris f. sp. Passiflora bacterium shows a potential for commercialization creating an interest genotype in breedings programs. Whereas the tissue culture has been an important instrument for those programs, object of this program is to study the anatomical and physiologycal aspects of organogenesis "in vitro" of this specie. The explants used were: root segments, leaf discs and the seedlings obtained from germination of seeds "in vitro". They were placed in different solutions of 6-BA (benzyladenine) and with 5% of coconut water, in order to establish protocol for plant regeneration "in vitro". The concentration of 0,5 mg.L- 1 of 6-BA was the most adequate for all three explants, but the time and nourishement source (direct/indirect) to the shoots formation differed to each kind of explants. The histological events had lead the formation of a new organ, by meristemoids (meristematic centers) were described. In the leaf discs the indirect origin, was observed in which callus were formatted by the layer of chlorophyll parenchyma subepidermis cells. In the root segments and in the root plantets, the direct organogenesis showed two origins (source), from the pericycle, on the roots that starts at the secondary structure and from vascular cambium, on the roots that had already been established secondary structure. Also the root segments was seen by the indirect way, which callus were formatted by the pericycle proliferation.
62

Porta-enxertos e manejo de cachos no desempenho da videira apir?nica ?BRS Vit?ria? / Rootstocks and clusters management on performance of ?BRS Vit?ria? apirenic grapevine

PERMANHANI, Miqu?ias 29 September 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-09-25T17:50:35Z No. of bitstreams: 1 2016 - Miqu?ias Permanhani.pdf: 8462509 bytes, checksum: 23e7a0fff474c07ddaca0105da127c59 (MD5) / Made available in DSpace on 2018-09-25T17:50:35Z (GMT). No. of bitstreams: 1 2016 - Miqu?ias Permanhani.pdf: 8462509 bytes, checksum: 23e7a0fff474c07ddaca0105da127c59 (MD5) Previous issue date: 2016-09-29 / CAPES / ?BRS Vit?ria? is the first seedless grape cultivar launched by Embrapa Grape and Wine with tolerance to downy mildew (Plasmopora viticola), in addition to presenting high fertility of buds and a special flavor similar to raspberry but its clusters are compact, which requires the establishment of specific management techniques to reduce compactness. Two trials were conducted in the northwestern S?o Paulo state aiming to evaluate the agronomic performance of ?BRS Vit?ria? grapevine grafted onto different rootstocks, as well as the effect of shoots and/or clusters tipping together with the application of gibberellic acid (GA3) on production and characteristics of fruits. In the first experiment, the treatments were constituted by the combination of ?BRS Vitoria? grapevine grafted onto rootstocks ?Paulsen 1103?, ?Kober 5BB?, ?IAC 766? and ?IAC 572?, while in the second trial four tipping modalities (control or without tipping, shoots, clusters, shoots + clusters) were done in the end of flowering stage, associated or not with the GA3 application (0 and 30 mg L-1) when berries had 6-8 mm of diameter. It was verified that the period from beginning of ripening to harvest of clusters had greater influence in the production cycle (from pruning to harvest) of scion/rootstock combinations, presenting longer and shorter interval, respectively, when grafted onto ?IAC 766? and ?Paulsen 1103?. There was obtained higher production and vegetative vigor when grafted onto ?IAC 766? and ?IAC 572?, being that the ?IAC 766? provided the higher average of clusters weight and berries size. The rootstocks did not influence in total soluble solids (TSS) content and titratable acidity (TA) of the berries. In addition, there was no effect of the tipping treatments on production and characteristics of fruits, except for the TSS content, indicating that this technique may not be efficient to reduce clusters compactness of ?BRS Vitoria? grape or that it should not be performed during the flowering period. However, the clusters tipping in association with the use of GA3 allowed a higher average TSS content by reducing the difference between berries at the top and tip of cluster. One single application of GA3 at 30 mg L-1 when berries had 6-8 mm of diameter provided an increase in fruits weight and size but there was no significant effect (p> 0.05) on production and, although it has not caused a negative impact on quality of ?BRS Vitoria? grape, a decrease was observed in TSS content and TSS/TA ratio of the berries. / ?BRS Vit?ria? ? a primeira cultivar de uva sem sementes lan?ada pela Embrapa Uva e Vinho com toler?ncia ao m?ldio (Plasmopora viticola), al?m de apresentar alta fertilidade de gemas e um sabor especial semelhante ? framboesa, por?m seus cachos s?o compactos, o que exige o estabelecimento de t?cnicas espec?ficas de manejo para reduzir a compacidade. Foram conduzidos dois experimentos na regi?o noroeste do estado de S?o Paulo com o objetivo de avaliar o desempenho agron?mico da videira ?BRS Vit?ria? enxertada sobre diferentes porta-enxertos, bem como, o efeito do desponte de ramos e/ou de cachos em conjunto com a aplica??o do ?cido giber?lico (GA3) na produ??o e nas caracter?sticas dos frutos. No primeiro experimento, os tratamentos foram constitu?dos pela combina??o da videira ?BRS Vit?ria? enxertada sobre os porta-enxertos ?Paulsen 1103?, ?Kober 5BB?, ?IAC 766? e ?IAC 572?, enquanto no segundo experimento, foram realizadas quatro modalidades de desponte (testemunha ou sem desponte, ramos, cachos, ramos + cachos) no est?gio de fim do florescimento, associados ou n?o com a aplica??o de GA3 (0 e 30 mg L-1) quando as bagas apresentavam 6-8 mm de di?metro. Foi verificado que o per?odo do in?cio da matura??o ? colheita dos cachos teve maior influencia no ciclo de produ??o (da poda ? colheita) das combina??es copa/porta-enxerto, apresentando intervalo mais longo e mais curto, respectivamente, quando sobre ?IAC 766? e ?Paulsen 1103?. Obteve-se maior produ??o e vigor vegetativo sobre ?IAC 766? e ?IAC 572?, sendo que o ?IAC 766? proporcionou maiores m?dias de massa de cachos e tamanho de bagas. Os porta-enxertos n?o influenciaram no teor de s?lidos sol?veis totais (SST) e acidez titul?vel (AT) das bagas. Al?m disso, n?o houve efeito do desponte na produ??o e nas caracter?sticas dos frutos, exceto para o teor de SST, indicando que essa t?cnica pode n?o ser eficiente para reduzir a compacidade dos cachos de uva ?BRS Vit?ria? ou que n?o deve ser realizada durante o per?odo de florescimento. No entanto, o desponte de cachos associado com o uso do GA3 possibilitou um maior teor m?dio de SST ao reduzir a diferen?a existente entre bagas na parte superior e na ponta do cacho. Uma ?nica aplica??o de GA3 a 30 mg L-1 quando as bagas tinham 6-8 mm de di?metro proporcionou um aumento na massa e no tamanho dos frutos, por?m n?o houve efeito significativo (p >0.05) na produ??o e, embora n?o tenha causado um impacto negativo na qualidade da uva ?BRS Vit?ria?, observou-se uma redu??o no teor de SST e na rela??o SST/AT das bagas.
63

Investigations into senescence and oxidative metabolism in gentian and petunia flowers

Zhang, Shugai January 2008 (has links)
Using gentian and petunia as the experimental systems, potential alternative post-harvest treatments for cut flowers were explored in this project. Pulsing with GA₃ (1 to 100 µM) or sucrose (3%, w/v) solutions delayed the rate of senescence of flowers on cut gentian stems. The retardation of flower senescence by GA₃ in both single flower and half petal systems was accompanied by a delay in petal discoloration. The delay in ion leakage increase or fresh weight loss was observed following treatment with 5 or 10 µM GA₃ of the flowers at the unopen bud stage. Ultrastructural analysis showed that in the cells of the lower part of a petal around the vein region, appearance of senescence-associated features such as degradation of cell membranes, cytoplasm and organelles was faster in water control than in GA₃ treatment. In particular, degeneration of chloroplasts including thylakoids and chloroplast envelope was retarded in response to GA₃ treatment. In the cells of the top part of a petal, more carotenoids-containing chromoplasts were found after GA₃ application than in water control. In petunia, treatment with 6% of ethanol or 0.3 mM of STS during the flower opening stage was effective to delay senescence of detached flowers. The longevity of isolated petunia petals treated with 6% ethanol was nearly twice as long as when they were held in water. Senescence-associated petal membrane damage, weight decline, ovary growth and decrease in protein and total RNA levels were counteracted in ethanol-treated petals. The accumulation of ROS, particularly superoxide and hydrogen peroxide, was also inhibited or delayed by ethanol application. Anti-senescence mechanisms, particularly the changes of oxidative / antioxidant metabolism involved in petal senescence, were investigated. In gentian, activities of AP and SOD but not POD in the GA₃-treated petals were significantly higher than those of the control. In isolated petunia petals, the decreased trends of antioxidative SOD and AP activities during senescence were apparently prevented in response to ethanol treatment although the levels of ascorbate and photo-protective carotenoids were not affected. Furthermore, by optimizing a range of critical PCR parameters such as primer combinations, cDNA concentrations and annealing temperatures, a reliable protocol has been established for quantifying the expression level of Cu-Zn SOD gene in petunia petals using SYBR Green I based real-time RT-PCR. A 228 bp gene fragment of Cu-Zn SOD was isolated from petunia (var. 'hurrah') using RT-PCR. It was found that the mRNA level (relative to 18S rRNA level) of Cu-Zn SOD decreased significantly after 6 days in water. However, there was about a 55-fold increase in Cu-Zn mRNA level after 6 days of ethanol treatment when compared to water-treated petals. Similarly, down-regulation of the mRNA level of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was also observed during senescence of petunia petals. Increased vase life of petunia petals by ethanol treatment was correlated with promotion of GAPDH expression by a factor of about 16 on day 6. Taking together, the anti-senescence effects of GA₃ and ethanol are at least partially associated with an increased efficiency of petal system utilizing ROS since the selected antioxidants were significantly maintained when compared to the corresponding values for the control.
64

Crescimento e florescimento de plantas de copo-de-leite submetidas a doses de GA3 e baixa temperatura / Growth and flowering of arum lilly submitted to GA3 concentration and low temperature

Mesquita, Eliane Rezende 26 August 2011 (has links)
Made available in DSpace on 2015-03-26T13:39:46Z (GMT). No. of bitstreams: 1 texto completo.pdf: 3599764 bytes, checksum: fe5c9c9fdc7ef5671686bcbc401f0257 (MD5) Previous issue date: 2011-08-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Currently the arm of Brazilian agriculture, governed by flower activity, is characterized as highly profitable and promising. In this field, is increasing the use of techniques that increase the quantity and quality in the final products. Among the main products from flowers, increasing emphasis is given to the species Zantedeschia aethiopica, popularly known as Calla Lilies, who despite dominating market share considerably, little known about their behavior by hormone treatment, packaging or handling storage temperature. Thus, the objective was to evaluate the effect of gibberellic acid in rhizomes of arum, the process of packaging and maintaining them in cold storage and also of young plants in the production phytotechnical characters. To achieve this objective, three experiments. At first underwent rhizomes of arum lilly in solutions containing gibberellic acid (GA3) at concentrations of 0, 50, 100, 500 and 1000 mg L-1, using two sources of this hormone. In the second experiment, put up rhizomes in polyethylene and the set was stored at ambient conditions for up to 90 days after being planted and conduced until flowering plants. And finally the third, rhizomes were subjected to cold storage periods of 0, 10, 20, 30 and 40 days in the same way, young plants (60 days) were also stored in these conditions. It was observed that the presence of GA3 anticipates flowering and confers greater production of flowers in the same way, the storage process also increases the number flower stalks. On the other hand, the packing of rhizomes and seedlings did not affect the evaluated characteristics. / Atualmente o segmento da agricultura brasileira, governado pela atividade floricultura, se caracteriza como altamente lucrativo e promissor. Neste campo, é crescente a utilização de técnicas que incrementem quantidade e qualidade nos produtos finais. Dentre os principais produtos oriundos da floricultura, destaque crescente é dado à espécie Zantedeschia aethiopica, conhecida popularmente como copo-de-leite, que apesar de dominar considerável fatia do mercado, pouco se sabe sobre seu comportamento mediante tratamento com hormônios, embalagem ou manejo de temperatura de armazenamento. Dessa forma, objetivou-se avaliar o efeito da aplicação de ácido giberélico em rizomas de copo-de-leite, o processo de embalagem e manutenção dos mesmos em câmara fria e o armazenamento também de plantas jovens em caracteres fitotécnicos da produção. Para isso, realizaram três experimentos. No primeiro os rizomas de copo-de-leite foram imersos em soluções contendo ácido giberélico (GA3) nas concentrações de 0, 50, 100, 500 e 1000 mg L-1, utilizando-se duas fontes deste hormônio. No segundo experimento, acondicionaram-se rizomas em embalagens de polietileno e o conjunto foi armazenado em condições ambiente por até 90 dias, depois, plantados e conduzidos até o florescimento. No terceiro, rizomas foram submetidos ao armazenamento a frio em períodos de 0, 10, 20, 30 e 40 dias, da mesma forma, plantas jovens (60 dias) foram também armazenadas nessas condições. O GA3 antecipa o florescimento e confere maior produção de flores; da mesma forma, o processo de armazenamento também aumenta o número hastes de florais. Por outro lado, o acondicionamento de rizomas e plantas jovens não interferiu nas características avaliadas.
65

Uso de reguladores no controle do crescimento e no desempenho agronômico da cultura da soja cultivar CD 214 RR

Buzzello, Gederson Luiz January 2010 (has links)
O acamamento de plantas provoca perdas significativas no rendimento de grãos da cultura da soja e por isso estratégias de manejo para minimizar o acamamento são importante necessidade na agricultura atual. O objetivo desse trabalho foi estudar ação de reguladores de crescimento vegetal sobre o acamamento e outras características agronômicas da cultivar de soja CD 214 RR, em épocas de semeadura e densidades distintas. Foram conduzidos dois experimentos na Estação Experimental da Universidade Tecnológica Federal do Paraná, Campus Pato Branco. No primeiro experimento foram testados diferentes reguladores de crescimento, sob concentrações distintas. O delineamento experimental foi inteiramente ao acaso com trinta e um tratamentos e quatro repetições. As quatro melhores combinações de reguladores/concentrações neste experimento foram utilizadas no segundo experimento. O segundo experimento foi conduzido em delineamento experimental de blocos ao acaso, com 3 repetições, em um esquema fatorial 5x3x3, em que o primeiro fator correspondeu às quatro combinações de reguladores/concentrações selecionadas no primeiro experimento e, também, a testemunha sem aplicação; o segundo fator correspondeu a três diferentes épocas de semeadura (01 de novembro, 15 de novembro, e 11 de dezembro); o terceiro fator correspondeu a três diferentes densidades de semeadura, em que a população final para cada densidade foi de 200.000, 300.000 e 400.000 plantas ha-1. No primeiro experimento, foram avaliados o acamamento, injúria e estatura de planta, durante o desenvolvimento da cultura. No segundo experimento também foram avaliadas estas variáveis, somente ao final do ciclo da cultura. No primeiro experimento foram coletadas amostras de plantas em 0,45 m2, na área útil da parcela, para posterior determinação dos componentes do rendimento, no estádio R9. Uma amostra foi coletada no estádio R8, representada por 10 plantas por parcela, em que foi obtido o índice de colheita e rendimento biológico aparente. Em ambos os experimentos, no estádio R9 da cultura, houve a colheita do restante da área útil da parcela, para determinação do rendimento de grãos. Os dados obtidos foram submetidos à análise de variância pelo teste F e foram comparados através de testes de comparação de médias. A relação entre variáveis dependentes e independentes foi ajustada através de regressão polinomial. Todos os tratamentos, de todos os seis grupos de reguladors vegetais foram eficientes em controlar o acamamento durante a maior parte do ciclo da cultura. O grupo do precursor de etileno ocasionou maior grau de fitotoxidade à cultura. Os compostos inibidores de auxina, inibidores de protox e bioestimulantes (AIB, GA3 e cinetina) apresentaram bons resultados na redução de estatura e do acamamento, apresentando grau de fitotoxidade leve e rápida recuperação dos sintomas de injúria. Os reguladores trinexapac ethyl (312,5 g ha-1), IBA+GA3+cinetina (0,0375+0,0375+0,0675 g ha-¹) e lactofen (144 g ha-1) resultaram em rendimento de grãos mais elevados. Isoladamente, as três concentrações de ethephon estudadas apresentam menor número de vagens por planta, menor peso de grão e menor rendimento de grãos. Os efeitos de fitorreguladores sobre o rendimento de grãos e componentes foram dependentes dos níveis em que estes foram aplicados sobre as plantas de soja. Onze tratamentos perfizeram o grupo que apresentou os rendimento de grãos mais elevados, entre eles os compostos por trinexapac ethyl (312,5 g ha-1), IBA+GA3+cinetina (0,0375+0,0375+0,0675 g ha-1) e lactofen (144 g ha-1). Entre todos os tratamentos, três concentrações de ethephon estudadas apresentam menor número de vagens por planta, menor peso de grão e menor rendimento de grãos. O lactofen (144 g ha-1) promoveu maior redução em estatura, em plantas semeadas na primeira (01/11/08) e terceira época (11/12/08). Já o cloreto de mepiquat (250 g ha-1)foi mais eficaz na redução de estatura de plantas da terceira época de semeadura (11/12/08). O menor acamamento ocorreu na segunda época de semeadura, na densidade de 200.000 plantas ha-1. Considerando-se a média de densidades e épocas de semeadura, os reguladores TIBA (6 g ha-¹), lactofen (144 g ha-¹) e AIB+GA3+Cinetina (0,0375+0,0375+0,0675 g ha-¹) apresentaram o melhor desempenho na redução do acamamento. O maior rendimento de grãos de soja ocorreu na semeadura de 11 de dezembro, não sendo influenciado pela densidade de plantas nesta época. O menor rendimento de grãos em soja ocorreu na semeadura do início de novembro, na densidade de 400.000 plantas ha-1. No segundo experimento, as plantas de todos os tratamentos com regulador de crescimento não apresentaram sintoma de injúria na avaliação realizada no estádio R1 da cultura. / The lodging of plants causes significant losses in grain yield of soybean and therefore management strategies to minimize the lodging are important in agriculture today. The aim of this work was to study the action of reducers of plant growth on lodging and other agronomic characteristics of soybean CD 214 RR at sowing dates and different densities. Two experiments were conducted at the Experimental Station of the Federal Technological University of Paraná, Pato Branco Campus. In the first experiment, testing different reducers of growth under different concentrations. The experimental design was completely andomized thirty-one treatments and four replicates. The four best combinations of concentrations in this experiment were used in the second experiment. The second experiment was conducted in a randomized block design with 3 replicates in a 5x3x3 factorial design, where the first factor corresponding to four combinations of concentrations selected in the first experiment (and also the control), the second factor corresponded to three different sowing dates (01 November, 15 November, and December 11), the third factor corresponded to three different plant densities in the final population for each density was 200.000, 300.000 and 400.000 plants ha-1. The first experiment examined the lodging, injury and plant height during the development of the culture. In the second experiment also evaluated these variables at the end of the cycle. In the first experiment samples were collected from plants in 0,45 m2 in each parcel, for later determination of yield components, the stage R9. A sample was collected at the R8 stage, represented by 10 plants per plot, which was obtained harvest index and biological yield apparent. In both experiments, the R9 stage of culture, there was the harvest of the remainder of each parcel to determine the yield. The data were subjected to analysis of variance by F test and were compared by means of comparison tests of means. The relationship between dependent and independent variables was adjusted by polynomial regression. All treatments in all six groups retardant were efficient in controlling the lodging for most of the crop cycle. The precursor of ethylene group caused a greater degree of phytotoxicity to the crop. The compounds of auxin inhibitors, protox and biostimulators (IBA, GA3 and kinetin) were able to reduce height and lodging, with slight degree of phytotoxicity and with rapid recovery of symptoms injury. Reducers trinexapac ethyl (312.5 g ha-1), IBA +GA3 +kinetin (0.0375, 0.0375 and 0.0675 g ha-¹) and lactofen (144 g ha-1) resulted in yield higher. Individually, the three concentrations of ethephon studied have a lower number of pods per plant, lower weight and lower grain yield. The effects of growth regulators on yield and components were dependent on the levels at which they are applied on the soybean plants. Eleven treatments accounted for the group the higher yield, among them the trinexapac ethyl (312.5 g ha-1), IBA GA3 kinetin (0.0375, 0.0375 and 0.0675 g ha-¹) and lactofen (144 g ha-1). Among all the treatments, the plants that received the three concentrations of ethephon studied have a lower number of pods per plant, lower weight and lower grain yield. The lactofen (144 g ha- 1) provided greater reduction in height, plants sown in the first (01/11/08) and third time (11/12/08). Since the chloride doses (250 g ha-1) was more effective in reducing plant height of the third sowing date (11/12/08). Smallest lodging occurred in the second sowing date, density of 200.000 plants ha-1. Considering the average densities and sowing dates, regulators TIBA (6 g ha-1), lactofen (144 g ha-1) and IBA +GA3+Kinetin (0.0375+0.0375+0.0675 g ha-1) showed the best performance in reducing lodging. The highest yield of soybean at sowing occurred on December 11 and is not influenced by the density of plants at this time. The lower yield in soybean planting occurred in early November, with a density of 400.000 plants ha-1. In the second experiment, plants of all treatments with growth retardant had no symptoms of injury in the assessment at the R1 stage of culture.
66

Uso de reguladores no controle do crescimento e no desempenho agronômico da cultura da soja cultivar CD 214 RR

Buzzello, Gederson Luiz January 2010 (has links)
O acamamento de plantas provoca perdas significativas no rendimento de grãos da cultura da soja e por isso estratégias de manejo para minimizar o acamamento são importante necessidade na agricultura atual. O objetivo desse trabalho foi estudar ação de reguladores de crescimento vegetal sobre o acamamento e outras características agronômicas da cultivar de soja CD 214 RR, em épocas de semeadura e densidades distintas. Foram conduzidos dois experimentos na Estação Experimental da Universidade Tecnológica Federal do Paraná, Campus Pato Branco. No primeiro experimento foram testados diferentes reguladores de crescimento, sob concentrações distintas. O delineamento experimental foi inteiramente ao acaso com trinta e um tratamentos e quatro repetições. As quatro melhores combinações de reguladores/concentrações neste experimento foram utilizadas no segundo experimento. O segundo experimento foi conduzido em delineamento experimental de blocos ao acaso, com 3 repetições, em um esquema fatorial 5x3x3, em que o primeiro fator correspondeu às quatro combinações de reguladores/concentrações selecionadas no primeiro experimento e, também, a testemunha sem aplicação; o segundo fator correspondeu a três diferentes épocas de semeadura (01 de novembro, 15 de novembro, e 11 de dezembro); o terceiro fator correspondeu a três diferentes densidades de semeadura, em que a população final para cada densidade foi de 200.000, 300.000 e 400.000 plantas ha-1. No primeiro experimento, foram avaliados o acamamento, injúria e estatura de planta, durante o desenvolvimento da cultura. No segundo experimento também foram avaliadas estas variáveis, somente ao final do ciclo da cultura. No primeiro experimento foram coletadas amostras de plantas em 0,45 m2, na área útil da parcela, para posterior determinação dos componentes do rendimento, no estádio R9. Uma amostra foi coletada no estádio R8, representada por 10 plantas por parcela, em que foi obtido o índice de colheita e rendimento biológico aparente. Em ambos os experimentos, no estádio R9 da cultura, houve a colheita do restante da área útil da parcela, para determinação do rendimento de grãos. Os dados obtidos foram submetidos à análise de variância pelo teste F e foram comparados através de testes de comparação de médias. A relação entre variáveis dependentes e independentes foi ajustada através de regressão polinomial. Todos os tratamentos, de todos os seis grupos de reguladors vegetais foram eficientes em controlar o acamamento durante a maior parte do ciclo da cultura. O grupo do precursor de etileno ocasionou maior grau de fitotoxidade à cultura. Os compostos inibidores de auxina, inibidores de protox e bioestimulantes (AIB, GA3 e cinetina) apresentaram bons resultados na redução de estatura e do acamamento, apresentando grau de fitotoxidade leve e rápida recuperação dos sintomas de injúria. Os reguladores trinexapac ethyl (312,5 g ha-1), IBA+GA3+cinetina (0,0375+0,0375+0,0675 g ha-¹) e lactofen (144 g ha-1) resultaram em rendimento de grãos mais elevados. Isoladamente, as três concentrações de ethephon estudadas apresentam menor número de vagens por planta, menor peso de grão e menor rendimento de grãos. Os efeitos de fitorreguladores sobre o rendimento de grãos e componentes foram dependentes dos níveis em que estes foram aplicados sobre as plantas de soja. Onze tratamentos perfizeram o grupo que apresentou os rendimento de grãos mais elevados, entre eles os compostos por trinexapac ethyl (312,5 g ha-1), IBA+GA3+cinetina (0,0375+0,0375+0,0675 g ha-1) e lactofen (144 g ha-1). Entre todos os tratamentos, três concentrações de ethephon estudadas apresentam menor número de vagens por planta, menor peso de grão e menor rendimento de grãos. O lactofen (144 g ha-1) promoveu maior redução em estatura, em plantas semeadas na primeira (01/11/08) e terceira época (11/12/08). Já o cloreto de mepiquat (250 g ha-1)foi mais eficaz na redução de estatura de plantas da terceira época de semeadura (11/12/08). O menor acamamento ocorreu na segunda época de semeadura, na densidade de 200.000 plantas ha-1. Considerando-se a média de densidades e épocas de semeadura, os reguladores TIBA (6 g ha-¹), lactofen (144 g ha-¹) e AIB+GA3+Cinetina (0,0375+0,0375+0,0675 g ha-¹) apresentaram o melhor desempenho na redução do acamamento. O maior rendimento de grãos de soja ocorreu na semeadura de 11 de dezembro, não sendo influenciado pela densidade de plantas nesta época. O menor rendimento de grãos em soja ocorreu na semeadura do início de novembro, na densidade de 400.000 plantas ha-1. No segundo experimento, as plantas de todos os tratamentos com regulador de crescimento não apresentaram sintoma de injúria na avaliação realizada no estádio R1 da cultura. / The lodging of plants causes significant losses in grain yield of soybean and therefore management strategies to minimize the lodging are important in agriculture today. The aim of this work was to study the action of reducers of plant growth on lodging and other agronomic characteristics of soybean CD 214 RR at sowing dates and different densities. Two experiments were conducted at the Experimental Station of the Federal Technological University of Paraná, Pato Branco Campus. In the first experiment, testing different reducers of growth under different concentrations. The experimental design was completely andomized thirty-one treatments and four replicates. The four best combinations of concentrations in this experiment were used in the second experiment. The second experiment was conducted in a randomized block design with 3 replicates in a 5x3x3 factorial design, where the first factor corresponding to four combinations of concentrations selected in the first experiment (and also the control), the second factor corresponded to three different sowing dates (01 November, 15 November, and December 11), the third factor corresponded to three different plant densities in the final population for each density was 200.000, 300.000 and 400.000 plants ha-1. The first experiment examined the lodging, injury and plant height during the development of the culture. In the second experiment also evaluated these variables at the end of the cycle. In the first experiment samples were collected from plants in 0,45 m2 in each parcel, for later determination of yield components, the stage R9. A sample was collected at the R8 stage, represented by 10 plants per plot, which was obtained harvest index and biological yield apparent. In both experiments, the R9 stage of culture, there was the harvest of the remainder of each parcel to determine the yield. The data were subjected to analysis of variance by F test and were compared by means of comparison tests of means. The relationship between dependent and independent variables was adjusted by polynomial regression. All treatments in all six groups retardant were efficient in controlling the lodging for most of the crop cycle. The precursor of ethylene group caused a greater degree of phytotoxicity to the crop. The compounds of auxin inhibitors, protox and biostimulators (IBA, GA3 and kinetin) were able to reduce height and lodging, with slight degree of phytotoxicity and with rapid recovery of symptoms injury. Reducers trinexapac ethyl (312.5 g ha-1), IBA +GA3 +kinetin (0.0375, 0.0375 and 0.0675 g ha-¹) and lactofen (144 g ha-1) resulted in yield higher. Individually, the three concentrations of ethephon studied have a lower number of pods per plant, lower weight and lower grain yield. The effects of growth regulators on yield and components were dependent on the levels at which they are applied on the soybean plants. Eleven treatments accounted for the group the higher yield, among them the trinexapac ethyl (312.5 g ha-1), IBA GA3 kinetin (0.0375, 0.0375 and 0.0675 g ha-¹) and lactofen (144 g ha-1). Among all the treatments, the plants that received the three concentrations of ethephon studied have a lower number of pods per plant, lower weight and lower grain yield. The lactofen (144 g ha- 1) provided greater reduction in height, plants sown in the first (01/11/08) and third time (11/12/08). Since the chloride doses (250 g ha-1) was more effective in reducing plant height of the third sowing date (11/12/08). Smallest lodging occurred in the second sowing date, density of 200.000 plants ha-1. Considering the average densities and sowing dates, regulators TIBA (6 g ha-1), lactofen (144 g ha-1) and IBA +GA3+Kinetin (0.0375+0.0375+0.0675 g ha-1) showed the best performance in reducing lodging. The highest yield of soybean at sowing occurred on December 11 and is not influenced by the density of plants at this time. The lower yield in soybean planting occurred in early November, with a density of 400.000 plants ha-1. In the second experiment, plants of all treatments with growth retardant had no symptoms of injury in the assessment at the R1 stage of culture.
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Cashews quality treated with aminoethoxyvinylglycine (AVG) and gibberellic acid (GA3) / Qualidade de cajus tratados com aminoetoxivinilglicina (AVG) e Ãcido geberÃlico (GA3)

Frederico Silva Thà Pontes Filho 30 September 2014 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / One of many problems that worry the cashew farmers is the very short post-harvest conservation of the peduncle, due to the fast firmness lost, negatively affecting the sales of this product. The use of growth regulators may be an alternative to improve the peduncle quality (keep flesh firmness), avoid waste (reduce the pre-harvest fall), increase the harvest time (reduce the seasonality), this way, dropping production costs in the cashew farming. The aim of this study was to evaluate the effect of AVG and GA3 spraying in pre-harvest, concerning the quality and production of pseudo fruits of dwarf cashew tree clones CCP 76 and 189, produced in the Northeast Brazilian Region. Thereunto, it was made five experiments, which the replications was the harvests times, for each treatment. The first was carried in randomized block, with two plants per unit and 10 fruits per plant, with following treatments (doses) for the CCP 76 clone: AVG 0 mg L-1 (water sprayed); AVG 40 mg L-1; AVG 80 mg L-1; AVG 120 mg L-1; GA3 40 mg L-1; GA3 80 mg L-1; and GA3 120 mg L-1. The studied characteristics was power of hydrogen (pH), soluble solids (SS), titratable acidity (AT), SS/AT relation, soluble sugar (AS), vitamin C (VC), total carotenoids (CT), total anthocyanins (ANT) and extractable polyphenols (PE). The second and the third experiments were carried in randomized blocks, with two plants per unit and 15 fruits per plant and two clones (CCP 76 and BRS 189). These experiments include the following treatments (doses): AVG and GA3 0 mg L-1 (water sprayed); 60 mg L-1, 120 mg L-1, 180 mg L-1 of AVG and 60 mg L-1, 120 mg.L-1, 180 mg.L-1 of GA3. For both clones the characteristics evaluated was break between spray and harvest, fruit fall before harvest, peduncle size, peduncle basal diameter, peduncle top diameter, cashew total mass, peduncle mass, nut mass and peduncle flesh firmness. The fourth and fifth experiments had same treatments and experimental set of the second and third. However the evaluated variables, for both clones, was: SS, AT, SS/AT relation, AS and VC. In the first experiment it was observed that the GA3 120 mg L-1 dose could be a alternative for the early dwarf cashew clone CCP 76, because it improved the commercial quality attributes of the peduncles. In the experiments two and three GA3 increased the break between the spraying and the harvest, the size and firmness of clones peduncles studied. In the two last experiments the GA3 increased the SS/AT relation of the peduncles of CCP 76 and BRS 189 early dwarf cashew clones. Therefore, besides it detain the maturation time, the growth regulators also improved some quality attributes of the peduncles, what is well wished due to the fact that the improvement of such attributes is predominantly made by genetic improvement, and this process, in the current conditions, takes a lot of time to be concluded. / Um dos vÃrios problemas que preocupam os cajucultores, especialmente os que pretendem atuar no comÃrcio de caju in natura, à a conservaÃÃo pÃs-colheita demasiadamente pequena dos pedÃnculos, atribuÃda à rÃpida perda de firmeza dos mesmos, afetando negativamente a venda desse pseudofruto. O uso de reguladores de crescimento pode ser uma alternativa para melhorar a qualidade do pedÃnculo (manter a firmeza da polpa), evitar o desperdÃcio (diminuir a queda prÃ-colheita), aumentar o tempo de colheita (abreviar a sazonalidade), desse modo, reduzindo custo de produÃÃo na cajucultura. O objetivo do trabalho foi avaliar o efeito da aplicaÃÃo de AVG e GA3 em prÃ-colheita, sobre a qualidade e produÃÃo dos pseudofrutos dos clones de cajueiro-anÃo-precoce CCP 76 e BRS 189, cultivados na regiÃo Nordeste do Brasil. Para tanto, foram realizados cinco experimentos, sendo as repetiÃÃes as datas de colheita, para cada tratamento. O primeiro foi realizado em blocos casualizados, com duas plantas por parcela e 10 frutos por planta, com os seguintes tratamentos (dosagens) para o clone CCP 76: 0 mg L-1 de AVG e GA3 (pulverizaÃÃo com Ãgua); 40 mg L-1 de AVG; 80 mg L-1 de AVG; 120 mg L-1 de AVG; 40 mg L-1 de GA3; 80 mg.L-1 de GA3; e 120 mg.L-1 de GA3. As caracterÃsticas analisadas foram: potencial hidrogeniÃnico (pH), sÃlidos solÃveis (SS), acidez titulÃvel (AT), relaÃÃo sÃlidos solÃveis/acidez titulÃvel (SS/AT), aÃÃcares solÃveis (AS), vitamina C (VC), carotenoides totais (CT), antocianinas totais (ANT) e polifenois extraÃveis (PE). O segundo e terceiro experimentos foram realizados em blocos casualizados, com duas plantas por parcela, 15 frutos por planta e dois clones de cajueiro (CCP 76 e BRS 189). Esses experimentos abrangeram os seguintes tratamentos (dosagens): 0 mg L-1 de AVG e GA3 (pulverizaÃÃo com Ãgua); 60 mg L-1 de AVG; 120 mg L-1 de AVG; 180 mg L-1 de AVG; 60 mg L-1 de GA3; 120 mg.L-1 de GA3; e 180 mg.L-1 de GA3. As caracterÃsticas analisadas, para ambos os clones, foram: intervalo entre a aplicaÃÃo e colheita, queda de frutos em prÃ-colheita, comprimento do pedÃnculo, diÃmetro basal do pedÃnculo, diÃmetro apical do pedÃnculo, massa total do caju, massa do pedÃnculo, massa da castanha e firmeza da polpa do pedÃnculo. O quarto e quinto experimentos tiveram os mesmos tratamentos e delineamento experimental do segundo e terceiro. Contudo as variÃveis analisadas, para ambos os clones, foram: SS, AT, relaÃÃo SS/AT, AS e VC. No primeiro experimento verifica-se que a dosagem de 120 mg L-1 de GA3 pode ser uma alternativa ao clone de cajueiro-anÃo-precoce CCP 76, pois melhora os atributos de qualidade comercial dos pedÃnculos. Nos experimentos dois e trÃs o GA3 aumentou o intervalo entre a aplicaÃÃo e colheita, tamanho e a firmeza dos pedÃnculos dos clones estudados. Nos dois Ãltimos experimentos o GA3 aumentou a relaÃÃo SS/AT dos pedÃnculos dos clones de cajueiro-anÃo-precoce CCP 76 e BRS 189. Portanto, alÃm de terem retardado o tempo de maturaÃÃo, os reguladores de crescimento tambÃm aprimoram alguns atributos de qualidade dos pedÃnculos, o que à bastante desejÃvel devido ao fato de que a melhoria de tais atributos à feita predominantemente via melhoramento genÃtico, e este processo, nas atuais condiÃÃes, leva muito tempo atà ser concluÃdo.
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Estudos anatômicos e fisiológicos da organogênese in vitro em Passiflora cincinnata MAST. / Anatomical and physiological studies of organogenesis in vitro of Passiflora cincinnata MAST.

Simone Pacheco Lombardi 23 January 2004 (has links)
O avanço da cultura do maracujazeiro no país impulsionado pela agroindústria de suco e a crescente demanda de fruta fresca, acarretou o surgimento de problemas, principalmente de ordem fitossanitária, doenças causadas por fungos, bactérias e vírus. A espécie Passiflora cincinnata Mast. por apresentar resistência à doença da parte aérea causada pela ba ctéria Xanthomonas campestris f. sp. passiflorae e, potencial para a comercialização constitui um genótipo de interesse em programas de melhoramento. Visto que a cultura de tecidos tem sido ferramenta importante nesses programas, o presente projeto visa o estudo aspectos anatômicos e fisiológicos da organogênese in vitro dessa espécie. Os explantes utilizados: segmentos radiculares, discos foliares e a própria plântula, obtidos da germinação de sementes in vitro, foram inoculados em meio contendo diferentes concentrações de 6-BA (6-benziladenina) e acrescido de 5% de água de coco, a fim de estabelecer os protocolos de regeneração de plantas in vitro. A concentração de 0,5 mg.L -1 de 6-BA foi a mais adequada para os três explantes, porém, o tempo e a via (direta/indireta) de formação da gema diferiu para cada tipo de explante. Os eventos histológicos que levaram a formação de um novo órgão, via meristemóides (centros meristemáticos) foram descritos. Nos discos foliares a origem foi indireta, com formação de calo a partir das células subepidérmicas das camadas de parênquima clorofiliano. Nos segmentos de raiz e nas raízes das plântulas, a organogênese direta apresentou duas origens, a partir do periciclo, nas raízes com início da estrutura secundária, e a partir do câmbio vascular, nas raízes com estrutura secundária já estabelecida. Também nos segmentos de raiz observou-se a via indireta, esta a partir da proliferação do periciclo. / The progress of passionfruit culture in the country stimulated by the juice agroindustry and due to an increased demand of fresh fruit have brought phytosanitary problems, such as, diseases caused by fungis, bacterium and virus. The Passiflora cincinnata Mast. a resistant specie to Xanthomonas campestris f. sp. Passiflora bacterium shows a potential for commercialization creating an interest genotype in breedings programs. Whereas the tissue culture has been an important instrument for those programs, object of this program is to study the anatomical and physiologycal aspects of organogenesis “in vitro” of this specie. The explants used were: root segments, leaf discs and the seedlings obtained from germination of seeds “in vitro”. They were placed in different solutions of 6-BA (benzyladenine) and with 5% of coconut water, in order to establish protocol for plant regeneration “in vitro”. The concentration of 0,5 mg.L- 1 of 6-BA was the most adequate for all three explants, but the time and nourishement source (direct/indirect) to the shoots formation differed to each kind of explants. The histological events had lead the formation of a new organ, by meristemoids (meristematic centers) were described. In the leaf discs the indirect origin, was observed in which callus were formatted by the layer of chlorophyll parenchyma subepidermis cells. In the root segments and in the root plantets, the direct organogenesis showed two origins (source), from the pericycle, on the roots that starts at the secondary structure and from vascular cambium, on the roots that had already been established secondary structure. Also the root segments was seen by the indirect way, which callus were formatted by the pericycle proliferation.
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Use of Plant Growth Regulators to Expand the Period of Sagebrush Seed Germination and Reduce the Risk of Restoration Failure: Laboratory Trials

Keefer, Chelsea Elizabeth 01 July 2019 (has links)
Seed germination during unhospitable environmental conditions can be a major barrier to direct seeding efforts in dryland systems. In the sagebrush steppe, Artemisia tridentata Nutt. ssp. wyomingensis and Artemisia arbuscula are important shrub species that are being used in restoration, but seeding success is highly sporadic due to inter-annual and intra-seasonal weather variability. Altering and expanding the period of germination, as a form of bet-hedging, may improve plant establishment. Our objective was to determine if we could expand the period of germination using plant growth regulators (PGRs) applied in a conglomerated seed coating treatment. In a laboratory study, the seed was either left untreated, conglomerated separately with two concentrations of a germination inhibitor, abscisic acid (ABA), or with two different germination promoters, gibberellic acid (GA3) and 1-Aminocyclopropane carboxylic acid (ACC), a precursor to ethylene. Seeds were incubated in a loam soil at five constant temperatures (5-25 C) for approximately three months. Results indicate that seed treatments with PGRs can delay or speed germination. The greatest response to the seed treatments was observed at 5 C. For example, at this temperature PGRs delayed the time for 25% of the seeds to germinate by a maximum of 35 and 21 d and decreased this time by 5 and 25 d for A. t. ssp. Wyomingensis and A. arbuscula, respectively. Field studies are needed to determine if the bet-hedging strategy developed in this study will increase the likelihood that some seeds will germinate during periods that are more favorable for plant establishment.
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TOTAL SYNTHESES OF BERGAMOTANE SESQUITERPENES AND LYCOPODIUM ALKALOIDS AND COMPUTATIONAL STUDY TOWARD DIAMINATION OF ALLENES AND [2+2] SELECTIVITY

Ye-Cheng Wang (14009903) 27 October 2022 (has links)
<p>Total synthesis of massarinolin A, purpurlides B, D, E, 2,3-deoxypurpurolide C, phleghenrines A and B were finished. A halogen bond promoted michael addiation was discovered during mechanism study toward diamination of allenes. Computational chemsitry study conducted toward the selectivity of 2+2 reaction supported the proposed key reaction during total synthesis of gibberellic acid 18.</p>

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