Made available in DSpace on 2016-12-23T14:37:33Z (GMT). No. of bitstreams: 1 Dissertacao Renata1.pdf: 698393 bytes, checksum: f16df390334c37049e9e2d8b70c94c42 (MD5) Previous issue date: 2005-07-01 / The annatto (Bixa orellana L.) is a Bixaceae and its seeds presented low percentage of germination. This work was carried out with the objective to study the maturation and germination of annatto seeds. The experimental follows a completely randomized design with four replication using 20 fruits or 50 seeds. In this research was evaluated vigor and germination capacity; and studied seed maturation process. The following experimental procedures was realized: At each inflorescence was identified in the anthesis; for each fruit harvested was determined: diameter, length, weight, color, moisture content and dry weight; and for extracted seeds were analyzed: color, moisture content, dry weight, weight of 1000 dried seeds, bixin content index, and the speed and percentage of germination. Also it was evaluated effects of temperatures and substrates in germination of intact and scarified seeds. In this case was employed the experimental design 2x4x6 factorial. It was utilized the following temperatures: 20, 25, 30 and 20-30ºC. Utilized substrates were: sand, vermiculite, fiber coconut, wood fiber, Plantmax® and paper roll. At the study of germination in vitro, it was utilized culture medium MS with different concentrations of agar and the experimental design was a 3x4 factorial considering: (i) intact seeds; (i) seeds without tegument; (iii) embryo axis; and (iv) four level of agar (4, 6, 8 e 10 g 1 L-1). Two replications were realized using five tubes with one seed per tube. The germination criterion adopted was the protrusion of the primary root with size equal or greater than 2 mm. Results show that: (i) the physiologic maturation, better vigor index and better drift of pigment of the seeds occurred for fruits harvest 77 days after anthesis; (ii) seeds presented dormancy before physiologic maturation; (iii) the utilization of the substrates sand, vermiculite and paper roll, under temperatures of 25, 30, 20-30ºC improved the germination; and (iv) seeds without tegument presented better percentage of germination in culture medium contained 4 g L-1 of agar. / O urucu (Bixa orellana L.) é uma Bixaceae, cujas sementes apresentam baixa taxa de germinação. Este trabalho teve como objetivo estudar a maturação e a germinação de sementes de urucu. Os estudos foram conduzidos no delineamento experimental inteiramente casualizado, com quatro repetições de 20 frutos e/ou 50 sementes, onde foram avaliados o vigor e a capacidade germinativa. Na maturação, cada inflorescência foi identificada na antese, e nos frutos avaliados: diâmetro, comprimento, peso, coloração, teor de água e massa seca; e, nas sementes, avaliados: massa de mil sementes, velocidade e porcentagem de germinação. Nas fases de maturação foram feitas extração e dosagem de bixina e cortes para estudo citológico. Na avaliação em diferentes temperaturas e substratos, foram utilizadas sementes intactas e sementes escarificadas, em esquema fatorial 2x6x4. Os substratos utilizados foram: a areia, a vermiculita, o pó de coco, o pó de serra, o Plantmax® e o rolo de papel Germites® e as temperaturas foram de 20, 25, 30 e 20- 30ºC. Sementes intactas, sementes sem tegumento e apenas eixos embrionários foram avaliados na germinação in vitro, onde foi utilizado meio de cultivo MS, com diferentes concentrações de ágar (4, 6, 8 e 10 g L-1) em esquema fatorial 3x4, com duas repetições de cinco tubos e uma semente por tubo. Avaliou-se a protrusão da xii raiz principal com 2 mm de comprimento e o desenvolvimento da radícula para eixos embrionários. Concluiu-se que: a maturação fisiológica, maior índice de vigor e teor de corante das sementes, ocorre aos 77 dias após a antese; há dormência após a maturação; os substratos: areia, vermiculita e rolo de papel, sob temperaturas de 25, 30, 20-30ºC podem ser considerados os melhores para a germinação; e, as sementes sem tegumento, em meio contendo 4 g L-1 de ágar, apresentaram maior porcentagem de germinação.

Made available in DSpace on 2016-12-23T14:37:39Z (GMT). No. of bitstreams: 1 PARTE I.pdf: 23933 bytes, checksum: b656ce50b97b84072d45b1c7cdb491d2 (MD5) Previous issue date: 2005-07-01 / The annatto (Bixa orellana L.) is a Bixaceae and its seeds presented low percentage of germination. This work was carried out with the objective to study the maturation and germination of annatto seeds. The experimental follows a completely randomized design with four replication using 20 fruits or 50 seeds. In this research was evaluated vigor and germination capacity; and studied seed maturation process. The following experimental procedures was realized: At each inflorescence was identified in the anthesis; for each fruit harvested was determined: diameter, length, weight, color, moisture content and dry weight; and for extracted seeds were analyzed: color, moisture content, dry weight, weight of 1000 dried seeds, bixin content index, and the speed and percentage of germination. Also it was evaluated effects of temperatures and substrates in germination of intact and scarified seeds. In this case was employed the experimental design 2x4x6 factorial. It was utilized the following temperatures: 20, 25, 30 and 20-30ºC. Utilized substrates were: sand, vermiculite, fiber coconut, wood fiber, Plantmax® and paper roll. At the study of germination in vitro, it was utilized culture medium MS with different concentrations of agar and the experimental design was a 3x4 factorial considering: (i) intact seeds; (i) seeds without tegument; (iii) embryo axis; and (iv) four level of agar (4, 6, 8 e 10 g L-1). Two replications were realized using five tubes with one seed per tube. The germination criterion adopted was the protrusion of the primary root with size equal or greater than 2 mm. Results show that: (i) the physiologic maturation, better vigor index and better drift of pigment of the seeds occurred for fruits harvest 77 days after anthesis; (ii) seeds presented dormancy before physiologic maturation; (iii) the utilization of the substrates sand, vermiculite and paper roll, under temperatures of 25, 30, 20-30ºC improved the germination; and (iv) seeds without tegument presented better percentage of germination in culture medium contained 4 g L-1 of agar. / O urucu (Bixa orellana L.) é uma Bixaceae, cujas sementes apresentam baixa taxa de germinação. Este trabalho teve como objetivo estudar a maturação e a germinação de sementes de urucu. Os estudos foram conduzidos no delineamento experimental inteiramente casualizado, com quatro repetições de 20 frutos e/ou 50 sementes, onde foram avaliados o vigor e a capacidade germinativa. Na maturação, cada inflorescência foi identificada na antese, e nos frutos avaliados: diâmetro, comprimento, peso, coloração, teor de água e massa seca; e, nas sementes, avaliados: massa de mil sementes, velocidade e porcentagem de germinação. Nas fases de maturação foram feitas extração e dosagem de bixina e cortes para estudo citológico. Na avaliação em diferentes temperaturas e substratos, foram utilizadas sementes intactas e sementes escarificadas, em esquema fatorial 2x6x4. Os substratos utilizados foram: a areia, a vermiculita, o pó de coco, o pó de serra, o PlantmaxÒ e o rolo de papel GermitestÒ e as temperaturas foram de 20, 25, 30 e 20-30ºC. Sementes intactas, sementes sem tegumento e apenas eixos embrionários foram avaliados na germinação in vitro, onde foi utilizado meio de cultivo MS, com diferentes concentrações de ágar (4, 6, 8 e 10 g L-1) em esquema fatorial 3x4, com duas repetições de cinco tubos e uma semente por tubo. Avaliou-se a protrusão da raiz principal com 2 mm de comprimento e o desenvolvimento da radícula para eixos embrionários. Concluiu-se que: a maturação fisiológica, maior índice de vigor e teor de corante das sementes, ocorre aos 77 dias após a antese; há dormência após a maturação; os substratos: areia, vermiculita e rolo de papel, sob temperaturas de 25, 30, 20-30ºC podem ser considerados os melhores para a germinação; e, as sementes sem tegumento, em meio contendo 4 g L-1 de ágar, apresentaram maior porcentagem de germinação.

Les réelles opportunités de croissance dont bénéficient les marchés liés à l'utilisation de fibres végétales en tant que renfort dans les matériaux composites sont intimement liées aux performances concurrentielles de ces fibres par rapport à celles de fibres de verre en particulier l’allégement, l’amortissement et l’isolation thermique. Dans l'industrie de la fibre de chanvre, le rouissage est le premier traitement appliqué aux plantes afin de faciliter la séparation des fibres de la partie ligneuse centrale de la tige. Ce traitement est actuellement réalisé de manière empirique en champ conduisant à l’obtention de fibres de qualité variable (couleur, morphologie, microstructure, composition biochimique, propriétés thermiques et mécaniques) ce qui constitue un frein à leur utilisation plus large dans des composites hautes performances. Par conséquent, la maîtrise du rouissage est primordiale. L’objectif de ce travail de thèse est de développer une approche globale de cette étape-clé de la production des fibres de chanvre en combinant à la fois l’étude du mécanisme biologique du rouissage, celle des caractéristiques intrinsèques des fibres et celle des émissions gazeuses et des odeurs associées à l’étape de rouissage. Différents items ont été particulièrement examinés :- L’influence de la durée du rouissage et de la période de récolte sur les caractéristiques intrinsèques des fibres de chanvre (couleur, morphologie, composition biochimique, microstructure, propriétés mécaniques, propriétés thermiques).- L’évolution des émissions de composés organiques volatils (COV) et de l'odeur lors du rouissage en champ.- La dynamique temporelle des densités de population des communautés bactériennes et fongiques pendant le rouissage- L'impact du rouissage en champ (climat méditerranéen) et du rouissage accéléré (conditions contrôlées en laboratoire) sur les propriétés microstructurales, thermiques et mécaniques d’un biocomposite polypropylène/fibre de chanvre / The natural fibres are increasingly used as reinforcements in polymer composites due to their challenging performances compared to conventional fibres in term of good specific mechanical properties, damping and thermal insulation. In the hemp industry, the retting is an upstream processing applied to the plants in order to facilitate the separation of fibres from the central woody part of the stem. This treatment is currently carried out in an empirical way in the fields that leads to a large variability in the hemp fibres instrinsic characteristics (color, morphology, biochemical composition, microstructure, thermal and mechanical properties) which limit their large use in high-performance composites. Therefore, controlling retting treatment is a crucial step. The aim of this thesis is to develop a global approach to this key step in the production of hemp fibers by combining the study of the biological mechanism of retting, the intrinsic characteristics of fibers and that of emissions volatile organic compounds and odors associated with the retting step. Different items were particularly examined:- The influence of retting duration and harvest period on the intrinsic characteristics of hemp fibers (color, morphology, biochemical composition, microstructure, mechanical and thermal properties).- The evolution of Volatile Organic Compounds (VOCs) and odors of hemp stems during field retting- Temporal dynamics of population densities of bacterial and fungal communities during retting- The impact of field retting (Mediterranean climate) and accelerated retting (controlled conditions in the laboratory) on the microstructural, thermal and mechanical properties of a polypropylene / hemp fibers biocomposite