• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 14
  • 10
  • 3
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 34
  • 34
  • 8
  • 5
  • 5
  • 5
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 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.
21

Estrutura e desenvolvimento de sementes de Paullinia L. (Sapindaceae) / Seed structure and development of Paullinia L. (Sapindaceae)

Polo, Sandra Heliany Obando 08 January 2006 (has links)
Orientadores: Sandra Maria Carmello-Guerreiro, Pedro Acevedo-Rodriguez / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-07T06:23:56Z (GMT). No. of bitstreams: 1 Polo_SandraHelianyObando_M.pdf: 4995213 bytes, checksum: c9f5b62469e312e4dcd4138e126bbd72 (MD5) Previous issue date: 2006 / Resumo: No presente trabalho foram estudadas a ontogenia, morfologia e anatomia das sementes de algumas espécies do gênero Paullinia L. (Sapindaceae), coletadas em diversas áreas dos estados de São Paulo, Rio de Janeiro e Paraná. Para fins morfológicos e conceituais foi estudada a ontogênese da estrutura carnosa na semente de Paullinia trigonia Vell. De forma a avaliar a importância dos caracteres da semente para fins taxonômicos foram estudadas a morfologia e anatomia do envoltório seminal, cicatriz e estrutura carnosa em sementes maduras de nove espécies do gênero Paullinia: P. elegans Cambess., P. spicata Benth., P. cupana Kunth, P. carpopodea Cambess., P. meliaefolia A. L. Juss., P. coriacea Casar., P. cristata Radlk., P. racemosa Wawra e P. trigonía Vell., pertencentes a cinco das treze seções estabelecidas por Radlkofer. Os resultados indicaram que no referente à ontogenia da estrutura carnosa em P. trigonia Vell., o tegumento externo participa da formação da estrutura carnosa em duas regiões da semente, na porção basal da rafe e o na área próxima da micrópila. O funículo não contribui na formação da estrutura carnosa. Essa estrutura carnosa foi denominada sarcotesta e o termo arilo, como tem sido descrito não foi usado. Aspectos relacionados com o desenvolvimento da estrutura carnosa, da flor estaminada e pistilada, foram comparados e discutidos com outros representantes do gênero e a família Sapindaceae. As características morfológicas das sementes apresentam notáveis diferenças entre as espécies. Três caracteres em conjunto permitem distinguir facilmente as espécies: l.Tamanho e forma estrutural da semente. 2.Morfologia da sarcotesta (termo usado para definir o tipo de estrutura carnosa nas nove espécies examinadas), proporção que cobre a semente e fissuras principalmente na região da anti-rafe. 3.Forma e tamanho da cicatriz, lóbulos na região da rafe e anti-rafe, dimensão e tipo de fusão das projeções e grau de constrição na área intermédia entre os lóbulos e as projeções da cicatriz. Os caracteres anatômicos de maior utilidade para diferenciar as espécies foram apresentados pelo envoltório seminal: comprimento do estrato exotestal e número de camadas e dimensões da mesotesta. Os caracteres analisados não forneceram indícios de um agrupamento apoiando as seções propostas por Radlkofer, mais são caracteres de utilidade potencial na taxonomía e identificação das espécies do gênero / Abstract: In this work were studied the ontogeny, morphology and anatomy of the seeds of some species of the genus Paullinia L. (Sapindaceae), collected in severa I areas in the states of São Paulo, Rio de Janeiro and Paraná. The ontogeny of the fleshy structure of the seed of Paullinia trigonia Vel!. was study for conceptual and morphological purposes. In order to evaluate the importance of the characters of the seed for taxonomic value, the morphology and the anatomy of the seed coat, scar, and fleshy structure were studied in mature seeds of nine species of the genus Paullinia: P. elegans Cambess., P. spicata Benth., P. cupana Kunth, P. carpopodea Cambess., P. meliaefolia A. L. Juss., P. coriacea Casar., P. crista ta Radlk., P. racemosa Wawra and P. trigonia Vell., species belonging to five out of thirteen sections established by Radlkofer. The results indicated that in the ontogeny of the fleshy structure, the outer integument participates in the formation of the fleshy structure in two regions in the seed: in the basal portion of the raphe and in the area near the micropyle. The funicle does not contribute in the formation of the fleshy structure. The fleshy structure was definited as sarcotesta. The term aril referring to this white structure is not used in our work. Aspects relating to the development of the fleshy structure and of the staminate and pistilate flowers, are compared and discussed with other representatives of the genus and the Sapindaceae family. The morphologic characteristics of the seeds present remarkable differences between the species. Three characters altogether allow distinguishing the species easily: 1. Structural size and shape of the seed. 2. Morphology of the white fleshy structure, characterized here as sarcotesta for nine species examined, proportion that covers the seed, and fissures mainly in the anti-raphe region. 3. Shape and size of the scar, lobules in the raphe and anti-rafe regions, dimension and type of fusion of the projections, as well as the degree of the constriction in the intermediate area between the lobes and the projections of the scar. The most useful anatomical characters to differentiate the species are the ones presented in the seed coat: dimension of the exotestal stratum and number of layers and dimensions of the mesotesta. The characters analyzed here do not offer indications of a clustering supporting the sections proposed by Radlkofer, but they are characters of potential utility in the taxonomy and identification of the species of the genus / Mestrado / Mestre em Biologia Vegetal
22

A Rapid Spectrophotometric Assay for Quantifying Seed Coat Saponins in Quinoa

Szabo, Sydney Diver 09 December 2020 (has links)
Background and objectives: The commonly used afrosimetric foam-height method for quantifying saponins in quinoa is rapid but imprecise. A rapid UV/Vis method, utilizing the Liebermann-Burchard (LB) color reaction, was compared to the foam method across a range of saponin levels in washed and unwashed seed. Findings: A 6 min UV/Vis method provided greater precision and accuracy than the afrosimetric method at the lower saponin levels found in washed quinoa. The afrosimetric method did not differentiate saponin levels below 0.6 mg/mL but allows for useful relative comparisons of saponin content in unwashed quinoa where the foam height is large. Conclusions: The UV/Vis method is superior for analyzing saponins present on washed quinoa seed, while the foam method is adequate for saponin measurements in unwashed seed. Significance and novelty: The UV/Vis assay provides a new tool that can be used for in-process quality control in large-scale processing facilities, allowing for rapid, accurate determination of completion of the desaponization step.
23

Assessing the Distribution and Impact of <I>Bean pod mottle virus</I> (BPMV) as a Re-emerging Virus, and <I>Soybean mosaic virus </I>(SMV) in Soybean Grown in Virginia

Mackasmiel, Lucas A. 10 September 2004 (has links)
<I>Bean pod mottle virus </I>(BPMV, Genus <I>Comovirus</I>, Family: <I>Comoviridae</I>)is an important virus in soybean (<I>Glycine max</I> (L.) Merrill), causing quality and yield loss due to seed coat mottling and seed weight reduction. Although BPMV has been known in Virginia since 1958 and has always been regarded as causing negligible losses, its impact is changing as BPMV incidence has increased in many soybean growing areas of Virginia and the USA in general. From 1997 to 2001, a total of five BPMV isolates (V-W1, V-W2, V-S98-1, V-S98-15 and V-S01-10) were collected in Virginia and characterized. In this study, the effects of these isolates were studied, alone or with Soybean mosaic virus (SMV, Genus Potyvirus, Family Potyviridae) strain SMV G1, and isolates S98-51 and S98-52, on selected soybean cultivars. Individual isolates of BPMV showed variable symptom severity, and resulted in yield loss of between 40.4 to 58.1%, while SMV caused 23.7% in the most severe interactions. Up to 100% yield loss was realized from double inoculations of selected BPMV and SMV isolates, BPMV V-S98-1 + SMV S98-52 and BPMV S98-15 + SMV S98-52 on Hutcheson and Hutcheson Roundup Ready&#174; (BC5) soybeans, respectively. Time of inoculation, a critical factor in the impact of many virus diseases, affected seed coat mottling in four cultivars and seed weight in two cultivars, in tests with four BPMV isolates and three stages of soybean development. All BPMV isolates inoculated to plants at vegetative stage V1-V3 severely increased seed coat mottling and reduced seed weight than those inoculated at V4-V6 and reproductive stage R1-R3. Seedlings grown from non-mottled seeds germinated more uniformly had fewer thin-stemmed seedlings and grew faster than those grown from mottled seeds. Inoculation of various cultivars and breeding lines showed that there was no correlation between the severity of virus-induced foliar symptoms, relative accumulation of SMV, and extent of seed coat mottling. Thus, by avoiding the presence of BPMV at an early growth stage through proper timing of planting to avoid vectors, proper cultural practices like weed control, use of SMV free seeds, and chemical control, it is possible to greatly improve seed quality and reduce yield losses in soybean. / Ph. D.
24

Catechyl-lignin tissues in Vanilla orchid and Candlenut: structure/property studies

Ristanti, Eky Yenita 24 May 2023 (has links)
In 2012, a new type of lignin, catechyl (C)-lignin was found in the seed coat of vanilla orchid (Vanilla planifolia) and Melocactus cacti, and later in the nutshell of Aleurites moluccana (candlenut). This caffeyl alcohol homopolymer is the exclusive lignin in vanilla seed coat but separated in time and/or location with guaiacyl (G)-lignin in candlenut. Unlike conventional guaiacyl/syringyl (G/S-lignins) with alkyl-aryl ether linkages, intermonomer linkages in C-lignin are connected by benzodioxane linkages which are stiffer than alkyl-aryl ether linkages. C-lignin is unusually stable against acid-catalyzed cleavage. Tissues with C-lignin are expected to exhibit high glass transition temperature (Tg) compared to tissues with G/S/H-lignin. C-lignin also probably shows high crystallinity due to its highly linear-homopolymer structure. The ability of some seed coats/nutshells in angiosperms to synthesize a new type of lignin is another level of lignin evolution. However, the role of C-lignin related to the function of the seed coat is unclear while it exhibits different behaviors to the regular G/S/H-lignin. These points motivated us to conduct cell-wall structure/property studies in the context of plant evolution, using microscopy, X-ray diffraction (XRD) and dynamic mechanical analysis (DMA). Light and electron microscopes were used to identify cell's size and type of intact and macerated vanilla seed coat and candlenut shell. Vanilla seeds are tiny, sized approximately 300μm and the surface is covered with dark-colored seed coat. Candlenut is slightly smaller than walnut, with uneven, hard, dark brown shell covering the nut. Microscopy observations indicated that both seed coat and nutshell are dominated by highly lignified cells, known as sclereids. The types of sclereids in vanilla seed coat and candlenut shell are different; vanilla seed coat has ostoesclereid-type cells, while candlenut shell has macrosclereid-type cells. XRD was used to study tissue with C-lignin crystallinity by comparing diffractograms of vanilla seed coat and candlenut shell to Southern Yellow Pine wood diffractograms. The Southern Yellow Pine wood diffractogram corresponds to a typical native cellulose in higher plants, that is cellulose I allomorph. Diffractogram XRD analysis on vanilla seed coat and candlenut shell shows similarities to Southern Yellow Pine native cellulose, suggesting that cellulose is the contributor for crystallinity in seed coat and nutshell, and this also indicated that tissues with C-lignin is not crystalline. Crystallinities of vanilla seed coat and candlenut shell determined using peak deconvolution methods were about half of Southern Yellow Pine crystallinity. DMA was used to measure Tg in vanilla seed coat and candlenut shell. Measurements were conducted in solvent-submersion mode using organic plasticizers to reduce the Tg to non-damaging temperatures. DMA measurement of vanilla seed coat and candlenut shell is challenging due to specimen size and shape. Specimen preparation for DMA measurement included seed coat purification for vanilla and cutting/milling for candlenut shell followed by specimen saturation in plasticizers. Compressive-torsion DMA was used to allow tiny specimens gripping. Vanilla seed coats exhibited higher glass transition temperature compared to wood, while candlenut shells exhibited various Tgs depending on specimen type/size. / Doctor of Philosophy / Lignin is a complex organic material that constructs higher plant cell walls. Lignin provides stiffness and strength and is the landmark of plant evolution to terrestrial life. Typically, lignin in hardwood/softwood has guaicayl and/syringyl (G/S) units derived from coniferyl/sinapyl alcohols. ln 2012, a new type of lignin, catechyl (C)-lignin, was found in the seed coat of vanilla orchid (Vanilla planifolia) and Melocactus cacti, and later in the nutshell of Aleurites moluccana (candlenut). C-lignin is a caffeyl alcohol homopolymer and is exclusive in vanilla seed coat but coexists with guaiacyl (G)-lignin in candlenut shells. This new type of lignin exhibits different behavior than G/S-lignin. C-lignin is unusually stable against acid-catalyzed hydrolysis. Intermonomer linkage in C-lignin is stiffer than G/S lignin(s); it is likely to have higher glass transition temperature (Tg) than normal lignin. Due to its linearity, tissue with C-lignin is also expected to be highly crystalline. C-lignin's roles are not well known and therefore, these are merit for structure/property studies in the context of plant evolution as bio-inspired new materials. Microscopy, X-ray diffraction (XRD), and dynamic mechanical analysis (DMA) were used to study vanilla seed coat and candlenut shell morphology, crystallinity, and glass transition temperatures (Tg), respectively. It was observed that the two tissues have different types of sclereids, but this is not associated with why vanilla seed coats exhibit only C-lignin while candlenut shells have both C /G-lignins. XRD scans revealed that C-lignin is not crystalline due to similarity of their diffractograms to those of wood. DMA measurements revealed that vanilla seed coat tissues exhibit higher Tg than tissue with G/S lignin as expected, while the Tg candlenut shells varied among specimen type and particle sizes.
25

Seed Coat Color in Flax (Linum usitatissimum L.) Conditioned by the b1 Locus, its Linkage with Simple Sequence Repeat Markers (SSRs) and its Association with Flower Shape, Flower Color, Fatty Acid Profile and Grain Yield

2015 January 1900 (has links)
Previously seed coat color in flax has been used as a phenotypic marker for specialty quality traits and currently there is an increasing demand to use seed coat color in flax to market flax for human and animal nutrition uses. Seed coat color was studied to 1) understand the inheritance of seed coat color conditioned by the b1 locus, to 2) understand the relationship of other important flax traits with seed coat color as well as to 3) identify markers that are linked to seed coat color for future marker assisted selection of seed coat color. Spearman’s rank correlation and an allelism test was used to show the inheritance of the alleles at the b1 locus. Bulked segregant analysis (BSA) was used to identify putatively linked markers with the b1 locus, these were then screened on the CDC Bethune x M96006 recombinant inbred line population. Furthermore, the CDC Bethune x M96006 and CDC Bethune x USDA-ARS Crystal recombinant inbred line populations were used to identify any important flax traits that had a significant relationship with seed coat color. It was shown that seed coat color conditioned by the b1 locus was stably inherited and that b1vg and b1 are allelic to one another. The results of the BSA showed that there were 17 candidates for linkage but when these markers were screened on the population only the Lu456 from linkage group (LG) six was identified to have linkage (χ²=3.90; P<0.05) with the b1 locus. Additionally, it was shown that the b1 seed coat color allele of the b1 locus had a pleiotropic effect on flower color and flower shape and that seed coat color was associated with linolenic fatty acid content. None of the traits examined were found to be associated with the b1vg allele of this locus. These results show that the b1 locus is likely present on linkage group six, more marker coverage on linkage group six of markers that are polymorphic between the two seed coat color parents would increase the accuracy of detection. Lastly, this study showed that plant breeders should consider using the b1vg allele that conditions the variegated seed coat color to mark unique lines with important combinations of traits because it sorted independently for seed quality traits. Whereas, the yellow seed coat color conditioned by the b1 allele was found to be associated with higher linolenic fatty acid content and the semi-lethality of this allele would make it not suitable for use in parental lines.
26

Iron bioavailability in low phytate pea

2014 April 1900 (has links)
Field pea (Pisum sativum L.) seeds have high nutritional value but also contain phytate which can inhibit the absorption and utilization of nutrients. Phytate is the main storage form of phosphorus in the seeds but chelates Fe, Zn and some other micronutrients and is not well digested by monogastrics. Peas with pigmented seed coats contain polyphenols which also have anti-nutritional properties. To increase the nutritional value of field pea seeds, two low phytate lines (1-150-81 and 1-2347-144) containing higher inorganic phosphorus concentration (IN-P) and lower phytate-phosphorus concentration (PA-P) than the normal phytate varieties were developed from CDC Bronco in previous research. The objectives of this research were 1) to determine the effect of genotype and environment on iron bioavailability in a set of five pea varieties differing in phytate concentration and iron concentration using in vitro digestion/Caco-2 cell culture bioassay; 2) to determine the effect of seed coats on iron bioavailability by testing whole seeds compared to dehulled seeds in varieties differing in seed coat pigmentation using in vitro digestion/Caco-2 cell culture bioassay; 3) to determine the inheritance of iron bioavailability in field pea by evaluating recombinant inbred lines differing in phytate concentration using in vitro digestion/Caco-2 cell culture bioassay; 4) to determine the effects of pea with the low phytate trait on body weight and hemoglobin concentration of chickens. Iron concentration (FECON) did not differ significantly between normal and low phytate varieties. Iron bioavailability (FEBIO) of the two low-phytate lines was 1.4 to 1.9 times higher than that of the three normal phytate varieties, and growing environment also had a significant effect on FEBIO. Peas with pigmented seed coats contained 7 times lower FEBIO than peas with non-pigmented seed coat. The removal of the seed coat increased the FEBIO in peas with pigmented seed coat 5 to 6 times. From previous research on PR-15 recombinant inbred lines (RILs) which were developed from a cross between low phytate line 1-2347-144 and a normal phytate variety CDC Meadow, it was found that PA-P was controlled by a single gene. FEBIO, in this study, was also found to follow a bimodal frequency distribution, characteristic of single gene control, and it was highly correlated with PA-P in the PR-15 lines. In vivo studies were used to evaluate iron absorption of chickens fed with low and normal phytate pea diets. The diets containing the low-phytate pea lines had no significant effect on chicken body weight and hemoglobin level, compared with the diets containing normal phytate pea varieties. An unexpected high FECON was discovered in the diets that was traced to the ingredients of limestone and dicalcium-phosphate which likely affected the experimental results.
27

Mapeamento de caracteres do tegumento da semente de soja e análise in silico dos marcadores microssatélites / Genetic mapping of soybean seed and in silico analysis of the microssatelites markers

Henning, Fernando Augusto 30 April 2007 (has links)
Made available in DSpace on 2014-08-20T13:44:42Z (GMT). No. of bitstreams: 1 dissertacao_fernando_henning.pdf: 464142 bytes, checksum: dafd04da655722e31d27a17fb98fb36d (MD5) Previous issue date: 2007-04-30 / The use of quality seeds is preponderant to obtain productive success in farming. Several are the factors that influence in the quality of seeds, and among these the flotations can be mentioned in the humidity of seeds and even the use of inadequate techniques in the crop. The coat of soybean seeds is the responsible for the protection of the embryo, therefore, more resistance to you factor that they will take the quality loss, minor will be the damages for the whole productive chain of soybean seeds. The introduction of characters of larger resistance of coat of soybean seed is related to the characteristic of the permeability of coat. Several studies demonstrate to exists soybean genotypes with different permeability characteristics. Based on these information took place the crossing among to cultivate commercial CD202 (yellow and permeable coat) with a lineage TP (black and semi-permeable coat). In the population generated by the crossing, grew this work with the following objectives: i) to Build a genetic map of the coat of soybean seed using markers microssatélites, RAPD and AFLP; ii) to Relate the markers microssatélites used in the construction of the genetic map of the coat of soybean, with the possible proteins codified by the sequences anchored by these markers in the bank of ESTs of the soybean. For the construction of the genetic map of the coat of soybean 600 primers microssatélites, 50 RAPD and 64 AFLP were tested. The markers selected as polimórficos, they were submitted to the analysis of Qui-square and contained in connection groups using the program MapMaker. The alignment among the sequences of the microssatélites with the database of ESTs was made through analyses in silico being used the program BLAST. Of the total of tested markers, they were used in the construction of the map 20 markers microssatélites, 2 RAPD and 11 AFLP, which were efficient in the formation of 13 connection groups. Among the 20 markers selected microssatélites, 4 presented homology with sequences of ESTs deposited in the database of the soybean, and some of these sequences possess indirect relationship with the quality of soybean seeds. / A utilização de sementes de qualidade é preponderante para se obter sucesso produtivo em uma lavoura. Diversos são os fatores que influenciam na qualidade das sementes, sendo que dentre estes podem-se citar as flutuações na umidade das sementes e até mesmo a utilização de técnicas inadequadas na colheita. O tegumento das sementes de soja é o responsável pela proteção do embrião, logo, quanto maior sua resistência a fatores que irão levar a perda de qualidade, menores serão os prejuízos para toda a cadeia produtiva de sementes de soja. A introdução de caracteres de maior resistência do tegumento da semente de soja está relacionada à característica da permeabilidade do tegumento. Diversos estudos demonstram existir genótipos de soja com diferentes características de permeabilidade. Baseado nestas informações realizou-se o cruzamento entre a cultivar comercial CD202 (tegumento amarelo e permeável) com uma linhagem TP (tegumento preto e semi-permeável). Na população gerada pelo cruzamento, desenvolveu-se este trabalho com os seguintes objetivos: i) Construir um mapa genético do tegumento da semente de soja utilizando marcadores microssatélites, RAPD e AFLP; ii) Relacionar os marcadores microssatélites utilizados na construção do mapa genético do tegumento da soja, com as possíveis proteínas codificados pelas seqüências ancoradas por estes marcadores no banco de ESTs da soja. Para a construção do mapa genético do tegumento da soja foram testados 600 primers microssatélites, 50 RAPD e 64 AFLP. Os marcadores selecionados como polimórficos, foram submetidos à análise de Qui-quadrado e agrupados em grupos de ligação utilizando o programa MapMaker. O alinhamento entre as seqüências dos microssatélites com o banco de dados de ESTs foi feito via análises in silico utilizando-se o programa BLAST. Do total de marcadores testados, foram utilizados na construção do mapa 20 marcadores microssatélites, 2 RAPD e 11 AFLP, os quais foram eficientes na formação de 13 grupos de ligação. Dentre os 20 marcadores microssatélites selecionados, 4 apresentaram homologia com seqüências de ESTs depositadas no banco de dados da soja, sendo que algumas destas seqüências possuem relação indireta com a qualidade de sementes de soja.
28

Geração de cDNAs, primers e caracterização estrutural do tegumento de sementes de soja / Cdna, primers development and structural characterization of the soybean seed coat

Miranda, Helen Lúcia da Cruz 11 July 2008 (has links)
Made available in DSpace on 2014-08-20T13:44:45Z (GMT). No. of bitstreams: 1 tese_helen_miranda.pdf: 927475 bytes, checksum: d105f02684c8c60f51894561bc5a61c7 (MD5) Previous issue date: 2008-07-11 / Soybean is one of the main world commodities and the seed is the key for high yields in this culture. Nevertheless, the soybean seed coat is the main modulator of seed quality, so, in this structure we could find answers for high seed quality production. The study goal is to identify structural contrasting traits, to obtain cDNA and to draw primers related to lignin synthesis and wax deposition in seed coat from two soybean genotypes. Plants were grown in greenhouse, flowers were identified and dated to follow the development after flowering until legumes were harvested (25, 30, 35, 40, 45, 50, 55 and 60 days). Seed coats were then analyzed in electronic microscopy and used to build a soybean seed coat cDNA library for permeability traits (lignin synthesis and wax deposition). In silico, analyzes were performed to obtain specific primers to detect soybean seed coat lignin and wax biosynthesis genes. According to the seed coat traits, we identified differences in the palisade cell thickness between genotypes. The protocol based on litio chloride was efficient to extract total RNA from both genotypes in all phases. The unidirectional cDNA multiplication was efficient for the generation of enough cDNA quantity for future projects. In silico analyzes allowed the development of 16 primers related to lignin and wax deposition biosynthesis in soybean seed coat. / A soja é uma das principais commodities mundiais e a semente o principal insumo para sua produção. O tegumento das sementes é o principal modulador da qualidade, podendo ser encontrado, nessa estrutura a resposta para a produção de sementes com caracteres superiores para vigor e viabilidade. O estudo teve como objetivo identificar características estruturais contrastantes, obter cDNA e desenhar primers relacionados à síntese de lignina e deposição de cera em tegumentos de sementes de soja de genótipos contrastantes em relação à permeabilidade CD 202 (permeável) e IAC Santa Maria 702 (semipermeável). As plantas foram cultivadas em casa de vegetação e a partir da primeira floração as flores foram marcadas para que o tempo de desenvolvimento de cada legume fosse identificado. Legumes com 25, 30, 35, 40, 45, 50, 55 e 60 dias de desenvolvimento foram coletados e os tegumentos extraídos e armazenados para extração de RNA. Tegumentos com 25, 40, 55 e 70 dias de desenvolvimento dos genótipos de soja CD 202 e IAC Santa Maria 702 também foram submetidos a Microscopia Eletrônica. Após a extração do RNA total, foram obtidos os RNAm, seguido do cDNA. Em paralelo foi realizada análise in silico para desenho de primers específicos de genes envolvidos na rota metabólica da lignina e na deposição de cera nas sementes. Foram detectadas diferenças na espessura da camada paliçádica dos tegumentos de sementes de soja dos genótipos CD 202 e IAC Santa Maria 702. O protocolo a base de cloreto de lítio foi eficiente para extrair RNA total de ambos os genótipos em todas as fases de coleta. A estratégia de multiplicação unidirecional do cDNA foi eficiente para geração de um volume considerável para o desenvolvimento de estudos futuros de expressão diferencial de genes. A análise in silico permitiu o desenvolvimento de 16 primers relacionados aos genes da lignina e da elongase.
29

Improving Breeding Selection of Seed Quality Traits for Food-Grade Soybeans

Escamilla Sanchez, Diana Marcela 29 January 2018 (has links)
Natto and sprout soybeans are produced using small-seeded soybeans and their production is a high value alternative to grow grain soybeans for food in U.S. The development of soybean cultivars with improved natto and sprout quality is crucial for maintaining and increasing the soyfood market. However, there is insufficient information on sprout soybean characteristics. Therefore, the first objective of this study was to evaluate seed and sprout traits as potential selection criteria and study the storage effect on sprout quality. Seeds can be a vehicle for transmission of pathogens capable of causing human illness. That is why, the second objective was to identify seed-borne pathogens on a commercial soybean cultivar and to evaluate different seed decontamination treatments. Finally, seed coat deficiency is an undesirable trait for natto soybean seeds because it causes inferior appearance of the product. Thus, the third objective was to identify quantitative trait loci (QTL) underlying seed coat deficiency (SCD) and associated markers. Results showed that seed size, high-, average- and low-quality sprout percentage, hypocotyl thickness and length and sprout yield are the most important variables for breeding sprout cultivars; and one-year seed storage at room temperature reduced sprout quality. Fusarium, Alternaria and Diaphorte were the most frequent genera isolated from soybean seeds, and 2% calcium hypochlorite and 5% acetic acid were promising seed disinfection treatments. A stable QTL, qSCD20_1, was identified across two years explaining up to 25% of the variation of SCD; and eight molecular markers tightly linked and nearby qSCD20_1 were identified. Information presented will be helpful for sprout and natto soybean cultivar development. / Master of Science
30

Untersuchungen zum Einkapseln von Sprosssegmenten für die Verwendung als künstliche Samen am Beispiel von Chrysanthemen und Rosen

Abdel-Rahman, Sayed Shehata Abdin 10 June 2003 (has links)
Seit einigen Jahren wird die Einkapselungstechnik für die Produktion künstlicher Samen oder zur Vorbereitung der Kryokonservierung genutzt. Das Ziel dieser Untersuchungen war es, Methoden zur Einkapselung von Dendranthema- und Rosa-Sprosssegmenten zu entwickeln und dadurch "künstliche Samen" herzustellen, die für die Konversion unter In-vitro- und Ex-vitro-Bedingungen geeignet sind. Es wurde mit den Dendranthema-Sorten `PS 27´, `Snowdon Weiß´, `Topfweiß´ und `Garden mum´ und mit der Rosensorte, Rosa hybrida `Kardinal´, gearbeitet. Von 3 bis 5 Wochen alten Sprosskulturen wurden 4 bis 5 mm lange Nodiensegmente entnommen und in der Gelmatrix eingekapselt. Sowohl das Alter der Sprosskulturen (Subkulturdauer) als auch die Position der Explantate am Spross hatten einen deutlichen Einfluss auf die Konversion. Die Konversion war bei den Sprossspitzen schneller und besser als bei den Nodiensegmenten. Bei Dendranthema konnte mit 5 Wochen alten Sprosskulturen gearbeitet werden. Bei den Rosen wurden bessere Ergebnisse mit Nodiensegmenten von 3 Wochen alten Sprosskulturen erzielt. Nach Optimierung der Gelmatrixkomponenten konnte für Dendranthema eine 100%ige Konversion unter sterilen Bedingungen erreicht werden, wenn der Gelmatrix (3% Na-Alginat) MS-Salze, Vitamine, 3% Saccharose und 1 mg/l IES zugesetzt wurden. Unter unsterilen Bedingungen erreichte die Sprossbildung 73%, wenn eine Zwei-Schicht-Kapsel mit einer nährstofffreien äußeren Schicht und Nährstoffen in der inneren Schicht verwendet wurde. Rosa hybrida `Kardinal´ hatte andere Ansprüche an die Nährstoffversorgung und die Zugabe von Wachstumsregulatoren als Dendranthema. Die Konversion der eingekapselten Nodiensegmente von Rosa hybrida `Kardinal´ erreichte auf einem Agar-Wasser-Medium fast 60%, wenn der Gelmatrix MS-Salze, Vitamine, 80 g/l bzw. 90 g/l Saccharose und 2 mg/l IBS zugesetzt wurden. Es wurden auch Nodiensegmente aus dem Gewächshaus direkt zur Einkapselung verwendet. Die Konversion dieser Nodiensegmente von Dendranthema `PS 27´ erreichte auf einem Agar-Wasser-Medium 75%, wenn der Gelmatrix MS + 4 mg/l IES zugesetzt wurden. Die eingekapselten Nodiensegmente von Dendranthema `PS 27´ konnten bei 4°C in einer MS + 1,0 mg/l IES-Lösung für 3 Monate gelagert werden. / Recently, the encapsulation technique is used for the production of artificial seeds or for cryopreservation. The aim of the present studies was to develop methods for encapsulation of Dendranthema- and Rosa-shoot segments to produce artificial seeds, that are suitable for the conversion under in vitro and ex vitro conditions. Dendranthema `PS 27´, `Snowdon Weiß´, `Topfweiß´ and `Garden mum´ and Rosa hybrida `Kardinal´ were used as plant material for the encapsulation. Nodal segments of about 4-5 mm length were taken as explants for the encapsulation. The conversion was influenced by the quality of the plant material used for encapsulation. The age of shoot cultures (subculture duration) and the position of explant on the shoot affected the conversion. The conversion of the shoot tips was faster and better than that of the nodal segments. With Dendranthema, 5 weeks old shoot cultures could be used, while in Rosa nodal segments of 3 weeks old cultures responded better. After optimization of the components of the gel matrix (3% Na-Alginat), 100% conversion could be recorded under sterile conditions for Dendranthema, when the gel matrix contained MS salts, vitamins, 3% sucrose and 1 mg/l IAA. The percentage of shoot formation reached 73% under non-sterile conditions, when a two-layer-capsule was used with a nutrient free cover layer and nutrients in the inner layer. Rosa hybrida `Kardinal´ had other nutritional and hormonal requirements compared with Dendranthema. The conversion frequency of the encapsulated shoot buds of Rosa hybrida `Kardinal´ reached almost 60% on agar-water-medium, when the gel matrix obtained MS salts, vitamins, 80 g/l or 90 g/l sucrose and 2 mg/l IBS. In this work, also shoot buds from the greenhouse were encapsulated directly. The conversion frequency of these encapsulated buds of Dendranthema `PS 27´ reached 75% on agar-water-medium, when the gel matrix contained MS + 4 mg/l IES. The encapsulated shoot buds of Dendranthema `PS 27´ could be stored for 3 months at 4°C in MS liquid medium.

Page generated in 0.4605 seconds