Orientador: Maurício Dutra Zanotto / Coorietador: Edvaldo Aparecido Amaral da Silva / Banca: Sergio Gonçalves Dutra / Banca: Pedro Bento da Silva / Banca: Marcelo de Almeida Silva / Banca: João Teixeira Whitaker / Resumo: O cártamo é uma planta oleaginosa cultivada em vários países do mundo devido ao grande uso de diferentes partes da planta, principalmente na produção de óleo de ótima qualidade para consumo humano. Entretanto, há carências de informações sobre o manejo da cultura e ao sistema de produção de sementes. Neste contexto, apesar de haver crescente interesse pela a cultura devido a sua rusticidade e para produção de biodiesel, as pesquisas sobre maturação de sementes ainda são escassas. Portanto, objetivou-se avaliar o ponto ideal de colheita de sementes e potencial produtivo em três acessos de cártamo colhidas em diferentes estádios de maturação. Os experimentos foram conduzidos na Fazenda Experimental Lageado, pertencente à Faculdade de Ciências Agronômicas - UNESP, localizada no município de Botucatu - SP. Foram utilizadas sementes de três acessos de cártamo (2106, 7329 e S-325) obtidos junto ao Instituto Matogrossense do Algodão (IMA-MT). Os experimentos tiveram início em Abril de 2016 e 2017, sendo que nos ensaios foi adotado delineamento experimental em blocos casualizados, com seis repetições para o primeiro experimento e sete para o segundo. Para a caracterização dos estádios reprodutivos, a etiquetagem foi realizada quando 50% das plantas da parcela estavam no estádio de florescimento pleno, assim as colheitas dos capítulos, em intervalos de quatro dias após a primeira colheita, foram iniciadas com 16 dias após o florescimento (DAF) e finalizadas com 52 DAF quando os capítu... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Safflower is an oleaginous plant cultivated in several countries of the world due to its great use of different parts of the plant, mainly in the oil production of great quality for human consumption. However, there is a lack of informations about crop management and the seed production system. In this context, despite there is growing interest for the crop, due to its rusticity and for biodiesel production, researches on seed maturation are still scarce. The aim of this study was to evaluate the ideal seed harvesting point and productive potential in three accessions of safflower harvested at different maturation stages. The experiments were conducted at the Lageado Experimental Farm, belonging to the Faculty of Agronomic Sciences - UNESP, located in the city of Botucatu - SP. Seeds of three safflower accessions (2106, 7329 and S-325) were used, obtained from the Instituto Matogrossense do Algodão (IMA-MT). The experiments started in April 2016 and 2017, and for the assays was adopted a randomized block experimental design, with six replicates for the first experiment and seven for the second. For the characterization of the reproductive stages, the labeling was performed when 50% of the plants in the plot were in the full flowering stage, so the chapters harvesting happened at intervals of four days after the first harvest, starting with 16 days after flowering (DAF) and finished with 52 DAF when the chapters were completely senesced, totalizing ten harvests. The water content, dry and fresh seed mass, first germination count and percentage of germination were determined. In the second experiment, at the end of the crop cycle, the production components and seed and oil productivity were evaluated. The water content of the seeds starts high and with the progress of the stages of maturation, a gradual decrease occurs in both accessions. The access 2106 obtained the maximum germination at ... / Doutor

Orientador: Edvaldo Aparecido Amaral da Silva / Banca: João Nakagawa / Banca: Daiani Ajala Luccas / Resumo: Sementes de alta qualidade fisiológica é pré-requisito para o estabelecimento da cultura e para a produção. A qualidade fisiológica das sementes é adquirida durante o desenvolvimento. O conhecimento sobre quando cada componente da qualidade fisiológica é adquirido durante a fase de maturação da semente permite um ajuste no momento ideal da colheita e consequentemente colheita no período em que a semente se encontra com o máximo de qualidade fisiológica. Portanto, o objetivo deste trabalho foi estudar a aquisição de germinação, tolerância à dessecação, vigor e longevidade durante a fase de desenvolvimento de duas cultivares de amendoim produzidas em duas safras agrícolas. A produção de sementes de duas cultivares, IAC OL3 e IAC 505 cultivada no ano de 2016/2017 e no ano de 2017/2018 seguida de coleta e caracterização morfológica das sementes nos estádios reprodutivos R5, R6, R7, R8 e R9. Para cada estádio foi determinado o teor de água, massa fresca, massa seca, germinação e o vigor das sementes. O vigor foi determinado pela seguintes avaliações: primeira contagem de germinação, T50, crescimento de raiz e parte aérea, massa de matéria seca de raiz e parte aérea e avaliação de protrusão. Em seguida, as sementes foram submetidas a secagem e foi realizada o teste de germinação para a determinação da aquisição de tolerância à dessecação. As sementes secas foram então armazenadas à 35°C e 75% de umidade relativa, para caracterizar a aquisição de longevidade. A germinação foi inicia... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Seeds of high physiological quality are pre-requisite for the establishment of the crop and for the production. The physiological quality of the seeds is acquired during development. Knowledge about when each component of physiological quality is acquird during the maturation phase of the seed allows an adjustment at the ideal time of harvest and consequently harvest in the period in which the seed meets the highest physiological quality. Therefore, the objective of this work was to characterize and understand the pattern of the acquisition of the components of physiological quality in peanut seeds (germination, desiccation tolerance, vigor and longevity). Seed production of two cultivars, IAC OL3 and IAC 505 was carried out in 2016/2017 and 2017/2018 followed by collection and morphological characterization of the seeds at the reproductive stages R5, R6, R7, R8 and R9. For each stage the water content, fresh weight, dry weight, germination and vigor on fresh seeds were determined. The vigor was determined by the following evaluations: first germination count, T50, root and shoot growth, root and shoot dry matter mass and protrusion evaluation. Then seeds were submitted to drying and carried out the germination test to determine the acquisition of desiccation tolerance. The dried seeds were then stored at 35°C and 75% relative humidity to characterize the acquisition of longevity. Germination was initiated at the R5 stage and reached its maximum at the R9 stage. The desiccati... (Complete abstract click electronic access below) / Mestre

The effects of petroleum mulches on the emergence and yield of tomatoes were studied at the Farmington Field Station, Greenville Field Station, North Logan, and the greenhouse. The mulches were applied as surface overlays above the seed or incorporating before plantin. Seedling emergence and yields were measured. Data recorded from trials conducted under cool weather conditions indicated that petroleum mulch overlays can be effective in increasing seedling emergence. The increased seedling emergence with petroleum mulch is due to increased soil temperature , less moisture loss from the surface, and a minimum of soil crust formation.

Fire is a recurrent disturbance that removes above ground vegetation in many locations throughout the world, including the Sydney region. Many species in fire-prone locations, and most species in the Sydney region, form soil seedbanks and regenerate through post-fire germination. However, a germination response is determined by the fire regime acting as a selective pressure over a sufficient period of time, rather than a single fire. The components of the fire-regime are intensity, season, type and frequency. The natural fire regime is dominated by warm-season fire, but management burning is conducted in cooler seasons. Cool season burning produces lower levels of germination than warm season fires in a number of locations with Mediterranean-type climate, but the effects of cool season burning on species composition in the relatively aseasonal Sydney region is unknown. An experimental approach was adopted to address this lack of knowledge. Fire can be simulated using heat shock and smoke (fire cues), and the seasonal factors of temperature and water availability can be reproduced in the laboratory. I have investigated the effect of various combinations of heat shock and smoke, of various pre-and post-fire cue temperatures, of prefire cue hydration status, of various post-fire cue water availabilities, and of accelerated aging before application of fire cues on germination of a number of species forming soil seedbanks in the Sydney region. A degree of primary dormancy was overcome in most species by the combination of heat shock and smoke in the current investigation. Fire intensity is expected to influence germination, as germination of most species was increased by the combination of heat shock and smoke within a narrow heat shock range.The interaction between ambient temperature and the level of heat shock may affect germination. Soil water content, and thus seed moisture content at the time of a fire may interact with the level of heat shock to affect both germination and survival of a seed. The age of a seed may also affect its germination response to fire. The above factors are predicted to affect the germination of species differently, and thus season of fire is expected to alter species composition. Such predictions can be readily field-tested / Doctor of Philosophy (PhD)

Fire is a recurrent disturbance that removes above ground vegetation in many locations throughout the world, including the Sydney region. Many species in fire-prone locations, and most species in the Sydney region, form soil seedbanks and regenerate through post-fire germination. However, a germination response is determined by the fire regime acting as a selective pressure over a sufficient period of time, rather than a single fire. The components of the fire-regime are intensity, season, type and frequency. The natural fire regime is dominated by warm-season fire, but management burning is conducted in cooler seasons. Cool season burning produces lower levels of germination than warm season fires in a number of locations with Mediterranean-type climate, but the effects of cool season burning on species composition in the relatively aseasonal Sydney region is unknown. An experimental approach was adopted to address this lack of knowledge. Fire can be simulated using heat shock and smoke (fire cues), and the seasonal factors of temperature and water availability can be reproduced in the laboratory. I have investigated the effect of various combinations of heat shock and smoke, of various pre-and post-fire cue temperatures, of prefire cue hydration status, of various post-fire cue water availabilities, and of accelerated aging before application of fire cues on germination of a number of species forming soil seedbanks in the Sydney region. A degree of primary dormancy was overcome in most species by the combination of heat shock and smoke in the current investigation. Fire intensity is expected to influence germination, as germination of most species was increased by the combination of heat shock and smoke within a narrow heat shock range.The interaction between ambient temperature and the level of heat shock may affect germination. Soil water content, and thus seed moisture content at the time of a fire may interact with the level of heat shock to affect both germination and survival of a seed. The age of a seed may also affect its germination response to fire. The above factors are predicted to affect the germination of species differently, and thus season of fire is expected to alter species composition. Such predictions can be readily field-tested / Doctor of Philosophy (PhD)

Thesis (Ph. D.)--University of North Texas, May, 2009. / Title from title page display. Includes bibliographical references.

Reproduction de : Thèse de doctorat : Biologie moléculaire et physiologie végétale : Toulouse, INPT : 2006. / Titre provenant de l'écran-titre. Bibliogr. 167 réf.

Thesis (Ph. D.)--Ohio University, 2006. / Includes bibliographical references. Also available in PDF format via the Internet.

All organisms have been subjected to and have evolved with the ubiquitous force of gravity, and most exhibit the ability to sense and respond to this stimulus. To simplify an investigation of the molecular components of a cell's gravity response, this dissertation employs the single-celled spores of the fern Ceratopteris richardii. These spores have a polar calcium flux that is determined by the gravity vector, but an understanding of what the molecular components driving this flux are and how they influence subsequent developmental processes is lacking. Of the possible molecular components, available literature pointed to Ca²⁺-ATPase transporters as an obvious key participant and so they were selected as the main molecule of investigation. Our results describe the first cloned Ca²⁺-ATPase from C. richardii, CrACA1. CrACA1 has high similarity to known plant Ca²⁺-ATPases, specifically plasma membrane (PM) Ca²⁺-ATPases from Arabidopsis, and exhibits in vivo Ca²⁺-ATPase activity. An improved method for the statistical analysis and presentation of qualitative RT-PCR data was employed. The RNA, as well as the protein, of CrACA1 is present during the polarity fixation window which supported the need for further analyses of the role of Ca²⁺-ATPases. Our results showing that Ca²⁺-ATPase inhibitors significantly alter the gravity-directed calcium flux of spores are consistent with previous work but offer valuable new insights. The spore PM Ca²⁺-ATPases have large impacts on the calcium flux and rhizoid growth but no appreciable impact on polar axis alignment. The results on endomembrane-type Ca²⁺-ATPases make it clear that this class of pumps has major roles in both axis alignment and tip growth; rhizoid growth is inhibited but alignment to the gravity vector is improved. The updated model for gravity perception responses in C. richardii spores places a strong emphasis on calcium channels and Ca²⁺-ATPases working in concert to result in a bottom-localized calcium pool to align the polar axis with hints of store-operated calcium mobilization. The work presented represents an increase in our knowledge of one way a single cell can respond to the force of gravity, offering testable hypotheses to further refine gravity perception models incorporating calcium localization. / text

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