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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.
311

Seed dormancy in barley (Hordeum vulgare L.) : comparative genomics, quantitative trait loci analysis and molecular genetics

Bonnardeaux, Yumiko Graciela January 2008 (has links)
[Truncated abstract] Under prolonged wet and damp conditions, barley grain with low dormancy can germinate precociously, a condition known as preharvest sprouting that causes a number of detrimental effects in grain quality. In particular, preharvest sprouting renders the grain unsuitable for malting. The aim of this study was to take a genomics approach to identify and characterise candidate genes that could be linked to the control of seed dormancy in barley. This thesis developed a bioinformatic strategy that exploited the availability of gene sequences with functional evidence in the model species of Arabidopsis and rice. The bioinformatic strategy integrated phenotypic data (QTL data) and comparative genomics for a targeted approach in identifying candidate genes with a high probability of having a conserved function in cereals. This bioinformatic study identified two candidate genes ERA1 and ABI2 with strong evidence for a role in seed dormancy based on their function in Arabidopsis in abscisic acid (ABA) signal transduction and their co-location to seed dormancy QTLs in Arabidopsis, rice and wheat. In order to establish whether the candidate genes mapped to seed dormancy QTLs in barley, QTL analyses were performed on a double haploid population, not previously studied, developed from a cross between Stirling, a major Australian malting cultivar, and Harrington, a major Canadian malting cultivar. This cross was specifically chosen for this study, as elucidation of chromosomal regions associated with seed dormancy in the background of a malting cultivar would make a significant contribution for the malting industry. '...' Identification of a seed dormancy QTL on the long arm of 3H, in a region syntenic to the wheat chromosome locations of ESTS aligning to the ERA1 and ABI2 genes, laid the foundation for physical and genetic mapping of the candidate genes to investigate whether the genes co-located to the QTL on 3H. Physical mapping of the genes in wheat barley addition lines confirmed their positions on the long arm of 3H. Genetic mapping of the ERA1 gene was performed using a CAPS marker developed in this thesis. The genetic mapping of the ERA1 gene did not place the gene within either of the minor QTLs on 3HL, although segregation distortion may have influenced the map position of this gene. Further investigation is required to resolve the positioning of the ERA1 and ABI2 genes in relation to the 3H seed dormancy QTL. The main outcomes of this study have been 1) identification of candidate genes for further study; 2) identification of QTLs on the long arm of 3H that were previously unknown; 3) demonstration of the potential differences in dormancy that can be achieved through the use of specific gene combinations, highlighting the importance of minor genes and the epistatic interactions that occur between them and; 4) the development of a CAPS marker for the ERA1 gene, which can be used to track the gene in barley breeding programs to observe its association with important agronomic traits. This thesis also pioneered the implementation of several new technologies including multiplex-ready PCR (Hayden et al. 2008) for fluorescence–based SSR genotyping and QTLNetwork (Yang et al. 2008) for statistical analysis of QTLs. Seed dormancy is a complex trait and is likely to involve the interplay of a number of genes that have a role in other developmental and regulatory processes.
312

Seed storage behaviour and germination characteristics of trees and shrubs of Hong Kong

Lam, Wing-yee, Vicky., 林詠怡. January 1999 (has links)
published_or_final_version / Ecology and Biodiversity / Master / Master of Philosophy
313

Radio-Frequency thermal treatments for agri-food products

Orsat, Valérie. January 1999 (has links)
Although radio-frequency (RF) methods have been used for decades in many heating and drying processes, there is still a need for more engineering design data related to the design of the applicators and the performance of these systems before costly prototypes are built. Energy, temperature, and the effect produced by the high frequency field parameters on biological materials need to be examined with regard to their effects on the resulting processing requirements. / Wheat-seed infection by a fungus such as Fusarium graminearum can considerably lower the seed germination and the quality of the harvest. A study was thus conducted to determine the combined effect of different levels of RF power, temperature, and moisture content on the quality of seed-grade wheat and fungus inactivation. Similar treatment combinations were studied with seed-grade soybean in view on improving germination. With higher power, higher temperature (90°C) and higher moisture content (14%), the fungus mortality significantly increased, with a fungal vigour of less than 0.1, and the germination quality of the seeds decreased to a germination vigour below 0.3. For soybean seeds, only treatments of low RF intensity (60°C) were successful in improving germination vigour especially at lowest moisture content typically found in stored seeds. / RF treated wheat was studied to identify the relationship between heating conditions and grain quality categorized in terms of kernel viability and structural damage. / The potential of an RF thermal treatment to improve and extend the storability of vacuum packaged carrot sticks was investigated. The results have shown that it is possible to treat carrot sticks to 60°C in less than 2 min to reduce the initial microbial load. The RF-treatments maintained colour, the vacuum of the packages, and the excellent taste of the carrot sticks. / RF heating was studied for the pasteurization of prepared samples of ham. The ham samples were brought to internal temperatures of 75 and 85°C, by RF heating with a 10 min residence time. The study indicates that radio-frequency heating can improve the storability of re-packed hams by reducing the bacterial load, reducing moisture loss during storage and maintaining an overall greater product quality. (Abstract shortened by UMI.)
314

Towards developing effective decontamination procedures for in vitro culture of embryonic axes excised from recalcitrant seeds.

Cherian, Jency. 27 May 2014 (has links)
Control of seed-associated micro-organisms is vital in reducing losses of plants of economic importance. Recalcitrant seeds being metabolically active and able to be stored only under conditions of high relative humidity makes it more difficult to control contaminants. Nevertheless, means need to be developed to eliminate, or at least curtail, seed-associated fungi and bacteria. The use of biological control is a highly recommended alternative to chemical control for reducing the risk of killing beneficial organisms, as well as in terms of health and environmental hazards. Furthermore, when working with seed-derived tissues, it is extremely important to optimise a method or methods to control contamination without compromising the viability or further development of the explants. The original aim of the present study was to determine whether the biocontrol agents, EcoT® and Eco77® (commercial products of the spores of Trichoderma harzianum) would effectively control/eliminate micro-organisms from the embryonic axes of Trichilia dregeana, while promoting growth under in vitro conditions. Other means were also tested for their efficacy in controlling contaminants; these were application of Benlate®, Nipastat® (a mixture of parabens), anodic water (the anodic fraction of an electrolysed dilute solution of calcium and magnesium chloride), sodium dichloro-isocyanurate (Medi-Chlor®[NaDCC]) and alginate gel encapsulation of the embryonic axes. Prior to the experiments, fungal contaminants from the embryonic axes were isolated on potato dextrose medium and identified using light microscopy. EcoT and Eco77 were initially individually tested by co-culture as conidial suspensions with the embryonic axes. A further approach used liquid culture (potato dextrose broth) as well as solid culture medium (based on sugarcane bagasse) in/on which the strains of Trichoderma harzianum had been grown. This was aimed at testing for the possible presence of compounds released by T. harzianum into the media, which might prove to be effective in curtailing/eliminating the axis-associated microflora. Among the different treatments tested, the best method was utilised to decontaminate the embryonic axes prior to minimal-growth storage (hydrated axes encapsulated in alginate gel ‘beads’). Penicillium spp. were predominant among the different fungi isolated, which included Fusarium spp., Rhizopus spp., Aspergillus niger and Aspergillus flavus. Co-culturing with T. harzianum for 24 h was successful in terms of the survival of the embryonic axes, although the roots produced were shorter than when axes were cultured alone, but had no effect in eliminating the contaminants. Longer periods of co-culturing with T. harzianum affected the germination of the embryonic axes of T. dregeana compared with axes germinated in the absence of the biocontrol agent (control). The culture filtrate negatively affected germination of the T. dregeana embryonic axes, although it was effective against the associated contaminants. Nipastat was effective in reducing the contamination, and, depending on the concentration, did not affect germination adversely. Medi-Chlor was highly effective in eliminating all the contaminants from axes in vitro. Both these treatments were therefore used to decontaminate axes before minimal-growth storage. All the NaDCC-treated, encapsulated axes examined after 14 d hydrated storage [in Magenta boxes] and after 14-42 d in polythene bags survived; however the axes stored in aluminium foil-lined bags and Eppendorf tubes soon lost viability. The recommendation is therefore made that the decontamination treatment based on use of NaDCC (or other preparations of sodium dichloro-isocyanurate) be tested on embryonic axes of a range of recalcitrant-seeded species, and, if successful, the procedure be introduced into cryopreservation protocols. The use of NaDCC has emerged as a promising method of eliminating contaminating microflora which otherwise compromise in vitro procedures, from seed-derived explants. Furthermore, containment of decontaminated encapsulated axes in sealed polythene bags offers an apparently ideal means of temporary storage and dissemination. The results should find considerable applicability when excised embryonic axes representing the germplasm of recalcitrant seeds, are cryoconserved. / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2013.
315

Testes de vigor e sanidade de sementes de Brachiaria brizantha cv. Marandú e Xaraés / Vigor tests and seeds of sanity for Brachiaria brizantha cv. Marandu and Xaraes

Melo, Paulo Alexandre Fernandes Rodrigues de [UNESP] 27 July 2016 (has links)
Submitted by Paulo Alexandre Fernandes Rodrigues de Melo null (pauloalexandrefernandes@outlook.com) on 2016-08-22T20:10:32Z No. of bitstreams: 1 Tese Paulo DEFINITIVA PRONTA ok.pdf: 953177 bytes, checksum: 39dc4897030305a36e5190161e832788 (MD5) / Rejected by Ana Paula Grisoto (grisotoana@reitoria.unesp.br), reason: Solicitamos que realize uma nova submissão seguindo a orientação abaixo: O arquivo submetido não contém o certificado de aprovação. A versão submetida por você é considerada a versão final da dissertação/tese, portanto não poderá ocorrer qualquer alteração em seu conteúdo após a aprovação. Corrija esta informação e realize uma nova submissão contendo o arquivo correto. Agradecemos a compreensão. on 2016-08-24T13:07:05Z (GMT) / Submitted by Paulo Alexandre Fernandes Rodrigues de Melo null (pauloalexandrefernandes@outlook.com) on 2016-08-24T14:21:16Z No. of bitstreams: 1 Tese Paulo DEFINITIVA PRONTA ok.pdf: 1174219 bytes, checksum: c4af725cb562ce91d1bc2b106d654730 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-08-24T18:11:32Z (GMT) No. of bitstreams: 1 melo_pafr_dr_jabo.pdf: 1174219 bytes, checksum: c4af725cb562ce91d1bc2b106d654730 (MD5) / Made available in DSpace on 2016-08-24T18:11:32Z (GMT). No. of bitstreams: 1 melo_pafr_dr_jabo.pdf: 1174219 bytes, checksum: c4af725cb562ce91d1bc2b106d654730 (MD5) Previous issue date: 2016-07-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Dentro de um programa de controle de qualidade, a avaliação da sanidade e do vigor das sementes é necessária para o sucesso da produção. Assim, o trabalho foi conduzido com o objetivo de identificar os fungos e verificar a eficiência de testes de vigor na diferenciação da qualidade dos lotes de sementes de Brachiaria brizantha cv. Marandú e Xaraés, visando obter informações sobre a qualidade sanitária das sementes e a emergência de plântulas em campo. Vinte lotes de sementes produzidas nos Estados de Mato Grosso do Sul, Mato Grosso, Goiás, Minas Gerais, São Paulo e Bahia foram submetidos à avaliação do teor de água, germinação e microflora fúngica, realizada pelo método do papel de filtro (blotter-test). Para avaliar o vigor e potencial fisiológico foram utilizados dezessete lotes de sementes, sendo oito da cultivar Marandú e nove da Xaraés, avaliados quanto ao teor de água, testes de germinação e vigor (primeira contagem de germinação, condutividade elétrica, emergência de plântulas, primeira contagem e índice de velocidade de emergência de plântulas em areia no laboratório e emergência de plântulas em campo). A microflora fúngica diagnosticada em sementes comerciais de capim marandú e xaraés é constituída por Helminthosporium sp., Fusarium sp., Phoma sp., Curvularia sp., Pyricularia grisea, Chaetomium sp., Nigrospora sp., Colletotrichum sp. e Aspergillus sp. não afeta a germinação de sementes de capim-marandú, no entanto, a incidência de Fusarium sp. e Aspergillus sp. reduz a germinação de sementes de capim-xaraés. Em relação aos locais de produção, nenhum se destacou quanto à qualidade sanitária das sementes produzidas. Os fungos mais disseminados, que ocorreram em mais de 90% dos lotes das diversas regiões de procedência foram Helminthosporium sp. em sementes de capim-marandú, Chaetomium sp. em capim-xaraés e Fusarium sp. em sementes de ambos os capins. Este é o primeiro relato de ocorrência de Pyricularia grisea em sementes de gramíneas forrageiras tropicais produzidas no Sudeste (Monte Alegre de Minas - MG) e Nordeste (Luís Eduardo Magalhães - BA) do Brasil. O teste de condutividade elétrica utilizando o método alternativo de amostragem de sementes imersas em 75 mL de água e leituras após duas ou quatro horas de embebição, assim como, os testes de germinação, emergência de plântulas e o índice de velocidade de emergência de plântulas em areia são os mais sensíveis na diferenciação do vigor e potencial fisiológico dos lotes de sementes visando à emergência de plântulas em campo para sementes dos capins marandú e xaraés, respectivamente. / Within a quality control program, the evaluation of health and seeds vigor are fundamental and necessary for the successful production. Thus, this study was conducted in order to identify fungi and verify the efficiency of vigor tests in the quality differentiating of Brachiaria brizantha cv., Marandu and Xaraes seed lots, in order to obtain information that improve the sanitary quality of seeds and seedling emergence in the field. Twenty seed lots produced in the states of Mato Grosso do Sul, Mato Grosso, Goias, Minas Gerais, Sao Paulo and Bahia were evaluated for water content, germination and fungal microflora by the filter paper method (blotter-test). To evaluate the vigor and potential physiological were used seventeen seed lots, eight of the cultivar Marandu and nine of the Xaraes submitted to the germination test, first counting of germination test, electrical conductivity, seedling emergence, first germination count and seedling emergence speed index in the sand performed in the laboratory and emergency seedling tests in the field. The fungal microflora diagnosed in commercial seed lots of marandu and xaraes grasses consists of Helminthosporium sp., Fusarium sp., Phoma sp., Curvularia sp., Pyricularia grisea, Chaetomium sp., Nigrospora sp., Colletotrichum sp. and Aspergillus sp.. germination of marandu grass seeds was not affected by the incidence of fungi. The incidence of Fusarium sp. and Aspergillus sp reduces the germination of xaraes Regarding producing locations, none stands out as to sanitary quality of the seeds produced. The grass seeds. This is the first report of the occurrence of Pyricularia grisea in tropical grasses seed produced in Southeast (Monte Alegre de Minas - MG) and Northeast (Luis Eduardo Magalhaes - BA) of Brazil. Electrical conductivity test using the sampling alternative method of seeds immersed in 75 mL of water and readings after two or four hours, as well as germination tests, seedling emergence and seedling emergence speed index in the sand are efficient in the evaluation of the vigor and potential physiological of seed lots of marandu and xaraes grass aiming to the seedling emergence in field respectively.
316

Etapas do beneficiamento na qualidade física, fisiológica e sanitária de sementes de capim-colonião /

Melo, Lilian Faria de. January 2016 (has links)
Orientador: Cibele Chalita Martins / Banca: Rouverson Pereira da Silva / Banca: Rita de Cássia Panizzi / Banca: Nilvanira Donizete Tebaldi / Banca: Marco Eustáqui de Sá / Resumo: As sementes de gramíneas forrageiras recebidas pelas empresas após a colheita contêm impurezas cuja remoção é realizada por máquinas de beneficiamento. Este procedimento é necessário para a obtenção de sementes dentro dos padrões de qualidade para a comercialização e a semeadura. O objetivo deste trabalho foi avaliar o efeito das etapas de beneficiamento na qualidade física, fisiológica e sanitária de sementes de Panicum maximum cultivares Tanzânia, Mombaça e Massai. As sementes foram amostradas antes do processamento e após a saída da máquina de ar e peneiras (descarga das peneiras superior, intermediária e fundo), primeira mesa gravitacional (deriva, descarga superior e intermediária), máquina tratadora e segunda mesa gravitacional (descarga superior, intermediária e inferior). As sementes foram avaliadas quanto ao teor de água, qualidade física (pureza e peso de mil sementes), fisiológica (germinação, primeira contagem, classificação do vigor de plântulas, envelhecimento acelerado, comprimento de plântulas, emergência de plântulas em campo e índice de velocidade de emergência) e sanitária (Blotter Test). O beneficiamento de sementes na máquina de ar e peneiras e mesa gravitacional é eficiente para o aprimoramento da qualidade física dos lotes das três cultivares de Panicum maximum e fisiológica somente para as cultivares Mombaça e Massai. O tratamento das sementes de Panicum maximum cultivar Tanzânia com tinta corante reduz a velocidade de emergência de plântulas em campo.... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The harvested seeds upon being received by the forage grass company, are found to be contaminated with impurities which are removable by processing machines. This procedure is necessary to produce seeds of a quality level within standards established for commercialization and sowing purposes The objective of this project was to evaluate the effects of processing phases on the physical, physiological and physiological quality of guinea grass cv. Tânzania, Mombaça and Massai (Panicum maximum) seeds for commercialization purposes. Seeds were sampled before processing and after leaving the air and screen machine (upper and intermediary screens and bottom); first gravity table (drift, upper and intermediate spouts); treating machine; second gravity table (upper, intermediate, and lower spouts). Seeds were evaluated as to water content, physical quality (purity and 1,000 seeds weight) and physiological (germination, first count of germination, seedling vigor classification, accelerated aging, primary root length, aerial part length, seedling emergence in the field, and speed of emergence index). The sanitary test was conducted according to the filter paper method (Blotter test) with the seeds being superficially disinfested. The processing of seeds in the air screen cleaner and gravity table is effective to improve the physical quality of batches of three cultivars of Panicum maximum and physiological only for Mombaça and Massai cultivars. Seed treatment with dye ink reduces the sp... (Complete abstract click electronic access below) / Doutor
317

Duração do teste de germinação de Brachiaria brizantha cv. Marandu (Hochst. ex A. Rich ) Stapf. /

Gaspar, Carolina Maria. January 2005 (has links)
Resumo: O tempo recomendado pelas Regras para Análise de Sementes (R.A.S.), para a conclusão do teste de germinação de Brachiaria brizantha, é considerado longo pelos laboratórios de análise, produtores e comerciantes dessas sementes, representando um entrave na tomada de decisões relacionadas à comercialização. O presente trabalho objetivou determinar o tempo mínimo necessário à realização do teste de germinação para sementes de B. brizantha cv. Marandu (Hochst. ex A. Rich.) Stapf e determinar o método de superação de dormência e a temperatura, recomendados pelas R.A.S., que proporcionem a maior germinação no menor tempo. A pesquisa foi conduzida em duas etapas. Na primeira, trinta lotes de sementes foram submetidos ao teste de germinação, com quatro repetições, sob duas condições de temperaturas alternadas (15-35ºC e 20-35ºC), sem (ausente) e com os seguintes métodos para a superação de dormência: umedecimento do substrato com KNO3 (0,2%) e imersão das sementes em H2SO4 (98% 36N) por 15 minutos, seguido de lavagem em água, constituindo 6 tratamentos. Realizaram-se contagens diárias do número de plântulas normais, para a determinação da data mais apropriada para o término do teste. Na segunda etapa foram realizados testes de germinação em oito lotes, sendo dois de alto vigor, quatro de médio vigor e dois de baixo vigor, nos mesmos 6 tratamentos e com encerramento nas datas definidas na primeira etapa da pesquisa. As sementes não germinadas após o término do teste de germinação foram submetidas ao teste de tetrazólio para verificar sua vitalidade, e, dessa forma, comprovar a eficiência da metodologia estabelecida na primeira etapa. O delineamento experimental considerou os lotes como repetições. Na primeira etapa para cada repetição, em cada combinação de tratamento, foi realizado um ajuste... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The time recommended by the Brazilian Rules for Seed Analysis (R.A.S.) for the ending of the Brachiaria brizantha germination test, is considered long for the analysis laboratories, producers and merchants of those seeds, representing a problem in taking decisions related to commercialization. The present work had as objective to define the minimum time necessary to carry out the B. brizantha cv. Marandu (Hochst. ex. A. Rich.) Stapf. germination test and determine the dormancy breaking method and the temperature, recommended by R.A.S, that provide the largest germination in the smallest period. The research was carried out in two parts. In the first, 30 lots of seeds were submitted to the germination test, with four replicates, under two conditions of alternated temperatures (15-35ºC and 20-35ºC), without (none) and with the following dormancy breaking methods: substrate moistened with a solution of KNO3 (0,2%) and immersion of the seeds in H2SO4 (98% 36N) for 15 minutes, followed by a wash in water, forming 6 treatments. Daily counting of the number of normal seedlings was carried out, to define the most adequate date to the end of the test. In the second part germination tests were carried out in eight lots, being two of high vigor, four of medium vigor and two of low vigor, in the same 6 treatments and with the ending in date indicated in the first part of the experiment. The remaining seeds at the end of the germination test were submitted to the tetrazolium test to verify their viability, and, thus, confirm the efficiency of the methodology defined in the first part. The experimental design considered the lots as replicates. In the first part for each replicate, in each treatment combination, a non-linear adjustment was accomplished, in which the function parameters were estimated, and a growth curve to determine the minimum time necessary to carry out... (Complete abstract, click electronic access below) / Orientador: Cibele Chalita Martins / Coorientador: Cláudio Cavariani / Banca: Joao Nakagawa / Banca: Adriana Martinelli Seneme / Mestre
318

Caracterização fisiológica e conservação de sementes de oito fruteiras nativas do bioma floresta com araucária

Pirola, Kelli 28 February 2013 (has links)
As fruteiras nativas brasileiras mesmo apresentando potencial de uso na agricultura, têm sido pouco exploradas comercialmente. Neste sentido, devem-se estimular estudos que permitam fomentar futuros programas de melhoramento e tecnologias para sua produção. O objetivo deste trabalho foi estudar o comportamento fisiológico de sementes de fruteiras do Bioma Floresta com Araucária, bem como, testar métodos para conservação das mesmas. O trabalho foi conduzido no Laboratório de Fisiologia Vegetal e no Viveiro de Produção de Mudas da Universidade Tecnológica Federal do Paraná – Câmpus Dois Vizinhos – Paraná. Foram utilizadas sementes de frutos maturos fisiologicamente das fruteiras nativas guabijuzeiro, guabirobeira, pitangueira, jabuticabeira de cabinho, jabuticabeira híbrida, cerejeira-do-mato, ameixeira da mata e sete capoteiro. Os frutos foram coletados conforme época de suas respectivas frutificações, em produtores da região Sudoeste do Paraná. Foi realizado quatro experimentos, sendo o primeiro para determinação do teor de umidade das sementes, onde adotou-se o delineamento inteiramente ao acaso, com 12 tratamentos e quatro repetições de 100 sementes. O segundo foi para verificar a longevidade das sementes durante 18 meses, por meio do armazenamento das mesmas em sacos de papel e garrafas PET® como embalagens e, adotando-se o uso ou não de fécula de mandioca como biofilme. O experimento foi instalado em delineamento inteiramente casualizado, em trifatorial 2 x 2 x 18 (embalagem de armazenamento x biofilme x período de armazenamento), com quatro repetições de 100 sementes. No terceiro fez-se estudo da dormência, testando técnicas para quebra da dormência em sementes destas oito fruteiras nativas, utilizando o uso de luz e sem luz. O experimento foi instalado em delineamento inteiramente casualizado, em esquema fatorial 2 x 7 (luminosidade x tratamento para quebra da dormência), com quatro repetições de 100 sementes. O quarto trabalho foi realizado para validação do teste de tetrazólio em sementes de jabuticabeira e cerejeira-da-mata armazenadas. A maior e mais rápida redução do teor de umidade diminuiu a capacidade germinativa das sementes de guabijuzeiro, jabuticabeiras híbrida e de cabinho e ameixeira-da-mata. A garrafa PET® permitiu maior conservação aumentando o número de sementes germinadas. O biofilme pode ser considerada técnica promissora para aumentar a eficiência no processo germinativo de cerejeira-da-mata. As sementes das espécies nativas estudadas não apresentam dormência, exceção para sete capoteiro que apresentaram dormência fisiológica controlada pelo fotoblastismo negativo, já que somente germinaram na ausência de luz. As sementes de cerejeira-da-mata (E. involucrata) podem ser conservadas em temperatura controlada (6°C) por pelo menos 45 dias. Sementes de jabuticabeira de cabinho (P. trunciflora) embaladas a vácuo conservam sua viabilidade por pelo menos 35 dias. O teste Tetrazólio apresentou-se viável e mais rápido para avaliar a viabilidade das sementes de cerejeira-da-mata e de jabuticabeira de Cabinho. / The Brazilian native fruits have potential use in agriculture, but it is little exploited commercially. In this sense, it should be encouraged studies for use in future breeding programs and obtain of technologies for its cultive. The aim of this work was to study the seed physiological characterization from native fruits Araucaria Forest Biome, as well as, it to test methods for seed storage. The work was carried out at Plant Physiology Laboratory and Nursery Sector of UTFPR - Câmpus Dois Vizinhos, Paraná State, Brazil. It was use seeds physiologically mature fruits Brazilian native from guabiju tree, guabiroba tree, Surinam Cherry tree, Cabinho and Hybrid jabuticaba tree, Native cherry tree, Native plum tree and sete capote tree. The fruits were harvested according period yield, in Southwest region of Paraná State. It was carried out four experiments, it being the first to identify the critical moisture content that affect seed germination, through the experimental design completely randomized, with 12 treatments and 4 replications of one hundred seeds by plot. The second was to evaluated the seed viability during 18 months through the PET® bottle (300 mL) and white waxed paper bag as storage packing and, the cassava starch biofilm application or not. The experimental design was blocks completely randomized, in factorial 2. x 2 x 18 (storage packaging x biofilm x storage time), with 4 replications of one hundred seeds by plot. In the third was dormancy study through it technical test for seeds break dormancy from eight fruit Brazilian trees, with or without light. The fourth experiment was realized for Tetrazolium test validation with jabuticaba fruit and Native cherry seeds stored. The greater and more rapid moisture content reduction decreased the guabiju seed tree, Hybrid and Cabinho seeds jabuticaba tree and Native plum tree germination process. However, new studies will be necessary to assess the seed viability on condition of lower moisture content. The PET® bottle permitted greater conservation, it increased the seed germination. The biofilm can be consider promising technique to increase germination efficiency of Native fruit cherry. The native Brazilian fruit seed species didn't have dormancy, except for sete capote fruit tree that presented morf were considered capoteiro showed physiological dormancy controlled by photoblastic negative response, it have germination only in the light absence. The Cabinho jabuticaba fruit (P. trunciflora) seeds vacuum packed maintains its viability about thirty five days. The Tetrazolium test presented viable and faster to evaluated the Native cherry and Cabinho jabuticaba fruit seeds viability.
319

Caracterização fisiológica e conservação de sementes de oito fruteiras nativas do bioma floresta com araucária

Pirola, Kelli 28 February 2013 (has links)
As fruteiras nativas brasileiras mesmo apresentando potencial de uso na agricultura, têm sido pouco exploradas comercialmente. Neste sentido, devem-se estimular estudos que permitam fomentar futuros programas de melhoramento e tecnologias para sua produção. O objetivo deste trabalho foi estudar o comportamento fisiológico de sementes de fruteiras do Bioma Floresta com Araucária, bem como, testar métodos para conservação das mesmas. O trabalho foi conduzido no Laboratório de Fisiologia Vegetal e no Viveiro de Produção de Mudas da Universidade Tecnológica Federal do Paraná – Câmpus Dois Vizinhos – Paraná. Foram utilizadas sementes de frutos maturos fisiologicamente das fruteiras nativas guabijuzeiro, guabirobeira, pitangueira, jabuticabeira de cabinho, jabuticabeira híbrida, cerejeira-do-mato, ameixeira da mata e sete capoteiro. Os frutos foram coletados conforme época de suas respectivas frutificações, em produtores da região Sudoeste do Paraná. Foi realizado quatro experimentos, sendo o primeiro para determinação do teor de umidade das sementes, onde adotou-se o delineamento inteiramente ao acaso, com 12 tratamentos e quatro repetições de 100 sementes. O segundo foi para verificar a longevidade das sementes durante 18 meses, por meio do armazenamento das mesmas em sacos de papel e garrafas PET® como embalagens e, adotando-se o uso ou não de fécula de mandioca como biofilme. O experimento foi instalado em delineamento inteiramente casualizado, em trifatorial 2 x 2 x 18 (embalagem de armazenamento x biofilme x período de armazenamento), com quatro repetições de 100 sementes. No terceiro fez-se estudo da dormência, testando técnicas para quebra da dormência em sementes destas oito fruteiras nativas, utilizando o uso de luz e sem luz. O experimento foi instalado em delineamento inteiramente casualizado, em esquema fatorial 2 x 7 (luminosidade x tratamento para quebra da dormência), com quatro repetições de 100 sementes. O quarto trabalho foi realizado para validação do teste de tetrazólio em sementes de jabuticabeira e cerejeira-da-mata armazenadas. A maior e mais rápida redução do teor de umidade diminuiu a capacidade germinativa das sementes de guabijuzeiro, jabuticabeiras híbrida e de cabinho e ameixeira-da-mata. A garrafa PET® permitiu maior conservação aumentando o número de sementes germinadas. O biofilme pode ser considerada técnica promissora para aumentar a eficiência no processo germinativo de cerejeira-da-mata. As sementes das espécies nativas estudadas não apresentam dormência, exceção para sete capoteiro que apresentaram dormência fisiológica controlada pelo fotoblastismo negativo, já que somente germinaram na ausência de luz. As sementes de cerejeira-da-mata (E. involucrata) podem ser conservadas em temperatura controlada (6°C) por pelo menos 45 dias. Sementes de jabuticabeira de cabinho (P. trunciflora) embaladas a vácuo conservam sua viabilidade por pelo menos 35 dias. O teste Tetrazólio apresentou-se viável e mais rápido para avaliar a viabilidade das sementes de cerejeira-da-mata e de jabuticabeira de Cabinho. / The Brazilian native fruits have potential use in agriculture, but it is little exploited commercially. In this sense, it should be encouraged studies for use in future breeding programs and obtain of technologies for its cultive. The aim of this work was to study the seed physiological characterization from native fruits Araucaria Forest Biome, as well as, it to test methods for seed storage. The work was carried out at Plant Physiology Laboratory and Nursery Sector of UTFPR - Câmpus Dois Vizinhos, Paraná State, Brazil. It was use seeds physiologically mature fruits Brazilian native from guabiju tree, guabiroba tree, Surinam Cherry tree, Cabinho and Hybrid jabuticaba tree, Native cherry tree, Native plum tree and sete capote tree. The fruits were harvested according period yield, in Southwest region of Paraná State. It was carried out four experiments, it being the first to identify the critical moisture content that affect seed germination, through the experimental design completely randomized, with 12 treatments and 4 replications of one hundred seeds by plot. The second was to evaluated the seed viability during 18 months through the PET® bottle (300 mL) and white waxed paper bag as storage packing and, the cassava starch biofilm application or not. The experimental design was blocks completely randomized, in factorial 2. x 2 x 18 (storage packaging x biofilm x storage time), with 4 replications of one hundred seeds by plot. In the third was dormancy study through it technical test for seeds break dormancy from eight fruit Brazilian trees, with or without light. The fourth experiment was realized for Tetrazolium test validation with jabuticaba fruit and Native cherry seeds stored. The greater and more rapid moisture content reduction decreased the guabiju seed tree, Hybrid and Cabinho seeds jabuticaba tree and Native plum tree germination process. However, new studies will be necessary to assess the seed viability on condition of lower moisture content. The PET® bottle permitted greater conservation, it increased the seed germination. The biofilm can be consider promising technique to increase germination efficiency of Native fruit cherry. The native Brazilian fruit seed species didn't have dormancy, except for sete capote fruit tree that presented morf were considered capoteiro showed physiological dormancy controlled by photoblastic negative response, it have germination only in the light absence. The Cabinho jabuticaba fruit (P. trunciflora) seeds vacuum packed maintains its viability about thirty five days. The Tetrazolium test presented viable and faster to evaluated the Native cherry and Cabinho jabuticaba fruit seeds viability.
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Florística e perfil de ácidos graxos em sementes de Cuphea (Lythraceae) em ambientes de Roraima / Floristic and profile of fatty acids in Cuphea (LYTHRACEAE) seeds in Roraima environments

Mayara Nunes Cardoso 21 June 2016 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Realiza o levantamento florístico de Cuphea no estado de Roraima e caracteriza os ácidos graxos de sementes das espécies nativas. / It carries out the floristic survey of Cuphea in the state of Roraima and characterizes the fatty acids of seeds of the native species.

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