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Ramirez, de Leon Hector. "Method of pollination and heritability for seedling vigor in switchgrass." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2374.
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Switchgrass (Panicum virgatum L.) is a warm-season perennial bunchgrass native to North America. In addition to its importance as a forage grass, it has promise as a biofuel crop. However, its use is limited because the grass is difficult to establish. Improving seedling vigor is one approach for improving establishment. The objectives of this study were to: 1) select for increased seedling mass through half-sib family selection; 2) calculate an estimate of heritability for seedling mass; and 3) determine the mode of pollination of switchgrass. One cycle of selection was completed using a half-sib methodology. Seedling mass was determined in a series of growth chamber studies. The seed was produced in different space planted field nurseries in the College Station, TX area. Mean seedling weight of the base population (C0) was 0.014 gm seedling-1, while the mean seedling weight from the C1 cycle of selection was 0.029 gm seedling-1. Unfortunately, bulked seed from the base population was old and did not germinate well. Therefore, a new base population was recreated, and the C0 seedlings from this population were heavier than the C1 seedlings, 0.020 and 0.016 gm seedling-1,
respectively. The calculated heritability estimate was H2 = 0.6. Since the C0 and C1 nurseries were not grown on the same soil type, the lack of a positive response for seedling weight may be due to the different soil types. However, it may require another cycle of selection to determine if seedling mass can be positively impacted via half-sib selection. The mode of pollination of the species was determined by 1) observing pollen germination and tube growth in the pistils using fluorescent microscopy and 2) determining seed set with selfed plants. When self-pollinated, the pollen tubes never grew into the ovaries but when cross-pollinated the tubes readily grew to the micropyle. Also, when switchgrass plants were self-pollinated, viable seed were not produced. These findings indicate that switchgrass is highly self-sterile because a self-incompatibility mechanism prevents the pollen tubes from growing into the ovary of the same genotype.
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Magalhães, Stefânia Caixeta. "Disponibilidade de minerais, germinação e vigor de sementes de milho /." Jaboticabal : [s.n.], 2009. http://hdl.handle.net/11449/96797.
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Orientador: Francisco Humberto Dübbern de Souza<br>Banca: Roberval Daiton Vieira<br>Banca: Ana Dionísia da Luz Coelho Novembre<br>Resumo: A maioria dos métodos utilizados para estimar o vigor de amostras de sementes são qualitativos, portanto sujeito a erros do avaliador e de interpretação dos resultados. Metodologias quantitativas podem constituir alternativas mais confiáveis. Este trabalho teve como objetivo verificar se os níveis de alguns minerais armazenados nas sementes e disponibilizados durante etapas iniciais do processo de germinação constituem indicadores sensíveis e confiáveis do nível de vigor de sementes de milho. Vinte lotes de milho foram avaliados pelos testes de germinação, de condutividade elétrica, frio e de emergência da plântula. Após 12 h, 24 h, 36 h e 48 h do início da germinação, foram avaliados também as concentrações de fósforo inorgânico (Pi), fósforo, cálcio, potássio e magnésio por meio das técnicas de análise de injeção em fluxo (FIA) e de espectrometria de emissão ótica acoplada a plasma de argônio induzido (ICP-OES). Para estas análises, os minerais foram extraídos de amostras moídas com água a 95ºC, agitadas por 30 minutos e centrifugadas. Concluiu-se que as concentrações de Pi, P, Ca, Mg e K, extraídos pelo método da água aquecida, em sementes de milho híbrido após determinados períodos de germinação, permitiram agrupar amostras de lotes de sementes de forma idêntica à permitida pelos resultados obtidos com vários testes utilizados para avaliar o nível de vigor de amostras de sementes. Nesse trabalho isso foi verificado pelas avaliações dos níveis de Pi após 12 h e 48 h, de P após 12 h, 36 h e 48 h, de Ca após 24 h, 36 h e 48 h, de Mg após 36 h e 48 h e de K após 36 h e 48 h de germinação.<br>Abstract: Most of the traditional methods used for seed vigor evaluation are qualitative and, as such, prone to errors and results misinterpretation. Quantitative methods may constitute more reliable alternatives. The aim of this work was to verify if the concentrations of some minerals stored in the seeds and made available during the initial stages of the germination process constitute sensitive and reliable indicators of the level of corn seed vigor. Twenty seed lots were evaluated by means of the germination, electrical conductivity, cold and seedling field emergence tests. Additionally, the concentrations of inorganic phosphorus, phosporus, calcium, potassium and magnesium at 12 h, 24 h, 36 h and 48 h after the initiation of the germination process were also evaluated by means of the injection analysis in flow (FIA) and the spectrometry of optic emission coupled to plasma of induced argon (ICP-OES) techniques. For these analyses grinded seed samples were extracted with water at 95ºC, agitated for 30 minutes and centrifuged . It was concluded that the concentrations of Pi, P, Ca, Mg and K, extracted by the warm water method, in hybrid corn seeds after certain stages of the germination process, allowed the rating the of seed lots in a way similar to that obtained with the results of several other seed vigor tests. Specifically, this was achieved by evaluating the concentratrions of Pi after 12 h and 48 h, of P after 12 h, 36 h and 48 h, of Ca after 24 h, 36 h and 48 h, of Mg after 36 h and 48 h and of K after 36 h and 48 h after the beginning of the germination process.<br>Mestre
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Magalhães, Stefânia Caixeta [UNESP]. "Disponibilidade de minerais, germinação e vigor de sementes de milho." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/96797.
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magalhaes_sc_me_jabo.pdf: 624079 bytes, checksum: 37a746a1dac768fd2d8f6dcc974b9b8d (MD5)<br>Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>A maioria dos métodos utilizados para estimar o vigor de amostras de sementes são qualitativos, portanto sujeito a erros do avaliador e de interpretação dos resultados. Metodologias quantitativas podem constituir alternativas mais confiáveis. Este trabalho teve como objetivo verificar se os níveis de alguns minerais armazenados nas sementes e disponibilizados durante etapas iniciais do processo de germinação constituem indicadores sensíveis e confiáveis do nível de vigor de sementes de milho. Vinte lotes de milho foram avaliados pelos testes de germinação, de condutividade elétrica, frio e de emergência da plântula. Após 12 h, 24 h, 36 h e 48 h do início da germinação, foram avaliados também as concentrações de fósforo inorgânico (Pi), fósforo, cálcio, potássio e magnésio por meio das técnicas de análise de injeção em fluxo (FIA) e de espectrometria de emissão ótica acoplada a plasma de argônio induzido (ICP-OES). Para estas análises, os minerais foram extraídos de amostras moídas com água a 95ºC, agitadas por 30 minutos e centrifugadas. Concluiu-se que as concentrações de Pi, P, Ca, Mg e K, extraídos pelo método da água aquecida, em sementes de milho híbrido após determinados períodos de germinação, permitiram agrupar amostras de lotes de sementes de forma idêntica à permitida pelos resultados obtidos com vários testes utilizados para avaliar o nível de vigor de amostras de sementes. Nesse trabalho isso foi verificado pelas avaliações dos níveis de Pi após 12 h e 48 h, de P após 12 h, 36 h e 48 h, de Ca após 24 h, 36 h e 48 h, de Mg após 36 h e 48 h e de K após 36 h e 48 h de germinação.<br>Most of the traditional methods used for seed vigor evaluation are qualitative and, as such, prone to errors and results misinterpretation. Quantitative methods may constitute more reliable alternatives. The aim of this work was to verify if the concentrations of some minerals stored in the seeds and made available during the initial stages of the germination process constitute sensitive and reliable indicators of the level of corn seed vigor. Twenty seed lots were evaluated by means of the germination, electrical conductivity, cold and seedling field emergence tests. Additionally, the concentrations of inorganic phosphorus, phosporus, calcium, potassium and magnesium at 12 h, 24 h, 36 h and 48 h after the initiation of the germination process were also evaluated by means of the injection analysis in flow (FIA) and the spectrometry of optic emission coupled to plasma of induced argon (ICP-OES) techniques. For these analyses grinded seed samples were extracted with water at 95ºC, agitated for 30 minutes and centrifuged . It was concluded that the concentrations of Pi, P, Ca, Mg and K, extracted by the warm water method, in hybrid corn seeds after certain stages of the germination process, allowed the rating the of seed lots in a way similar to that obtained with the results of several other seed vigor tests. Specifically, this was achieved by evaluating the concentratrions of Pi after 12 h and 48 h, of P after 12 h, 36 h and 48 h, of Ca after 24 h, 36 h and 48 h, of Mg after 36 h and 48 h and of K after 36 h and 48 h after the beginning of the germination process.
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Németh, M. Barbara. "Pollen Performance and Seedling Vigor in Laboratory and Natural Populations of Clarkia Unguiculata (Onagraceae)." Miami University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=miami1117816212.
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Sekharan, Soja. "Aged soybean (Glycine max [L.] Merrill) seeds – their physiology and vigor assessment." The Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=osu1135809134.
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Hatzig, Sarah Vanessa [Verfasser]. "Breeding for climate change : genetics and physiology of seed vigor, seedling vigor and early drought resistance in winter oilseed rape (Brassica napus L.) / Sarah Vanessa Hatzig." Gießen : Universitätsbibliothek, 2015. http://d-nb.info/108012019X/34.
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Godbey, Alan Lee. "Influence of phosphorus, sulfur, and molybdenum fertilization on the seedling vigor of selected legumes adapted to the Appalachian Region." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/50023.
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Legume establishment is difficult on many moderately acid, infertile soils in the humid northeastern United States. Legume seedling vigor as influence by P, S, and Mo fertilization was studied in order to determine fertilizer needs for improved establishment. A Gilpin silt loam was fertilized with 0, 22, 67, and 201 mg P kg⁻¹ in combination with 0, 22, 67, and 201 μg Mo kg⁻¹ in a greenhouse experiment in 1983. Legumes studied in this experiment were red clover (<i>Trifolium pratense</i>), white clover (<i>T. repens</i>), and birdsfoot trefoil (<i>Lotus corniculatus</i>). Field experiments with red clover, birdsfoot trefoil, and flatpea (<i>Lathyrus sylvestris</i>) were initiated in the spring of 1983 and 1984 using 0, 50, 150, and 450 kg P ha⁻¹, 0 and 60 kg S ha⁻¹, and 0 and 874 g Mo ha⁻¹. Seedling vigor as measured by plant height, trifoliate leaf count, dry weight, and trifoliate leaf area increased the greatest in the greenhouse using 22 mg P kg⁻¹ relative to the higher rates of P fertilization. Seedling vigor without applied P was poor, which clearly indicated the essential need for P in the early stages of legume growth. Molybdenum applied at 201 μg kg⁻¹ increased the growth of the greenhouse grown legumes the greatest above the 0 μg Mo kg⁻¹ rate within each added P treatment. Seedling vigor however, was not enhanced with Mo fertilization until the P deficiency was corrected. Field established legumes increased in height and dry matter yield the most using 50 kg P ha⁻¹ with respect to the additional increments of applied P, but the increase was not as great as that obtained in the greenhouse using 22 mg P kg⁻¹, This was attributed to a higher extractable P level before fertilization within the field experiments. Sulfur fertilization generally did not enhance seedling vigor in the field studies; although, red clover yield was increased using 60 kg S ha⁻¹ in the 1984 field experiment, Molybdenum applied at 874 g ha⁻¹ increased seedling vigor as measured by plant height and yield in the field experiments with or without P or S fertilization. Phosphorus uptake and Mo concentrations were increased in the plant tissues with either P or Mo fertilization.<br>Master of Science<br>incomplete_metadata
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Oliveira, Augusto Pedroso de. "Determinação da viabilidade e do vigor em sementes de seringueira." Universidade Federal de Goiás, 2012. http://repositorio.bc.ufg.br/tede/handle/tede/3208.
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Previous issue date: 2012-06-15<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>To produce rubber tree (Hevea brasiliensis) seedlings in nursery, the collection is limited by the short fall of seeds, which have a rapid loss of their germinal power and no guarantee their viability. This forces the nurseryman to acquire a much larger seeds than really necessary. With the adoption of standards for the quality of seed, the minimum parameters established 70% viability being suggested for such confirmation the tetrazolium test, according Rules for Seed Analysis (RSA) and/or a practical test done from the visual analysis of the seed endosperm color named in this work of "visual test". Despite tetrazolium test be scientifically based, its realization is made improbable by many financial and temporal reasons. Thus, the visual test points as a low-cost alternative, high reliability and immediate result, since both tests are considered trusted, but only the test tetrazolium test is recognized. The subject proposed to verify the credibility of the "visual test" legitimizing or not its use in the field. The field is composed of rubber seed, formed with the adult clone GT1. The seeds were homogenised and stored on two conditions: braided polypropylene bags and transparent plastic bags with minimum thickness of 0.02 mm microdrill at top. In each bag, in three treatments were placed ten kilograms of seed and these were stored in natural conditions of temperature and humidity (25° C ± 5 °C). Was pulled randomly a bag of seeds of rubber tree of each storage type, to zero and fourteen days of storing lots. The tests: visual, sprouting in sand and tetrazolium, besides the determination of the degree of moisture. Tetrazolium and visual tests were highly correlated, and the visual test results before had as the best way to analyze the seeds, for its significant correlation in General with the tetrazolium test, and simplicity in its execution and instant result, which gives good lot projection nurseryman to be acquired by him.<br>A produção de mudas de seringueira (Hevea brasiliensis) em viveiro, é limitada pelo curto período de produção, queda e coleta das sementes, que possuem uma rápida perda do seu poder germinativo e nenhuma garantia da sua viabilidade. Isto obriga o viveirista a adquirir uma quantidade de sementes maior do que aquela realmente necessária. Com a aprovação de normas para o padrão de qualidade de semente, se estabeleceram parâmetros mínimos de 70% de viabilidade sendo sugerido para tal confirmação o teste de tetrazólio, segundo as Regras para Análise de Sementes (RAS) e, ou, um teste prático feito a partir da análise visual da cor do endosperma da semente nomeado no presente trabalho de “teste visual”. Apesar do teste de tetrazólio ser embasado cientificamente, sua realização é inviabilizada por diversos motivos de ordem financeira e temporal. Sendo assim, o teste visual aponta como uma alternativa de baixo custo, alta confiabilidade e resultado imediato, já que ambos os testes são considerados confiáveis, mas apenas o teste de tetrazólio é reconhecido. Nesta pesquisa objetivou-se verificar a credibilidade do “teste visual” legitimando ou não seu uso no campo. As sementes de seringueira foram coletadas no município de Goianésia, estado de Goiás. O campo de sementes é constituido de seringal adulto, formado com o clone GT1. As sementes foram homogeneizadas e armazenadas em duas condições: sacos de polipropileno trançado e sacos plásticos transparentes com espessura mínima de 0,02 mm, microperfurados na parte superior. Em cada saco, nos dois tratamentos, foram colocados dez quilogramas de sementes e estes foram armazenados em condições naturais de temperatura e umidade (25° C ± 5 °C). Foi retirado aleatoriamente um saco de sementes de seringueira de cada tipo de armazenamento, no tempo zero e aos quatorze dias de armazenamento dos lotes de sementes coletados. Foram realizados os testes: visual, de germinação em areia e de tetrazólio, além da determinação do grau de umidade. Os testes visual e de tetrazolio foram altamente correlatos. O teste visual apresentou a melhor forma de análise das sementes, por sua significativa correlação no geral com o teste de tetrazólio, além da simplicidade em sua execução e resultado instantâneo, o que confere ao viveirista uma boa projeção do lote de sementes a serem adquiridas para a produção de mudas de seringueiras
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Weerasooriya, Dilooshi Kumari. "Genetic analysis of interveinal chlorosis and reduced seedling vigor as related to agronomic performance in sorghum resistant to ALS inhibitor herbicides." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32896.
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Doctor of Philosophy<br>Department of Agronomy<br>Tesfaye T. Tesso<br>The lack of effective post-emergence weed control options is often highlighted as one of the major factors behind dwindling acreage under sorghum (Sorghum bicolor (L.) Moench) in the United States. The discovery of herbicide resistance sources in wild sorghum population and subsequent efforts to incorporate them into cultivated sorghum was received with much optimism to change weed management practices in sorghum. As the development of the technology advances, especially of the Acetolactate synthase (ALS) resistance, concerns over the temporary interveinal chlorosis and reduced seedling vigor in some of the resistant families became heightened. This thesis research is designed to shed light on the genetic basis of seedling chlorosis and assess its impacts on yield potential.
The study has three parts; the first part is focused on identifying the genetic causes and plant mechanisms associated with the chlorotic phenotype. ALS herbicide resistant sister-lines expressing normal and chlorotic phenotypes were analyzed via RNA sequencing at four time points during seedling growth. The study identified several variants of genes coding chloroplast precursors and those that cause epigenetic modifications. Once confirmed, genetic markers can be developed to track these gene variants in the breeding population and eliminate segregates genetically prone to chlorosis/yellowing.
The second part of the study focuses on assessing the effect of ALS resistance associated chlorosis on agronomic and nutritional parameters of sorghum inbred lines. A set of ALS resistant lines expressing different levels of the chlorotic phenotype were evaluated in replicated field trials and laboratory methods. Results showed that interveinal chlorosis delays flowering but does not have negative effect on yield and nutritional parameters with and without herbicide treatment. The last part addresses whether there is any yield drag that may be associated with herbicide resistance traits and foliar interveinal chlorosis. For this, we synthesized a large set (182) of hybrids from ALS resistant, ACCase resistant and regular (susceptible) seed and pollinator parents. The hybrids were then evaluated in three sets at multiple locations during the 2014 and 2015 crop seasons along with commercial checks. The results revealed that resistance to both herbicides do not cause any drag to grain yield. The traits also do not have any negative impact on grain and nutritional quality of resistant hybrids.
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Teixeira, Everton Felix. "Análise de imagens digitais na avaliação de plântulas de milho." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-25042005-155848/.
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A análise de imagens digitais tem grande potencial de uso na determinação do vigor de sementes. Associada ao teste de crescimento de plântulas, essa técnica possibilita a análise dimensional de imagens com rapidez e precisão. O resultado é a extensão total de cada plântula via quantificação computadorizada do comprimento de suas partes constituintes. Assim, o objetivo do trabalho foi estudar o vigor de lotes de sementes de milho, por meio do teste de crescimento de plântulas, utilizando-se a análise de imagens. Plântulas de milho (genótipo AG122) foram retiradas do germinador ao quarto dia de desenvolvimento e ordenadas sobre uma folha de poliéster transparente na superfície de um scanner para a captação das imagens. Desenvolveu-se uma rotina de processamento no programa Scil-Image para a análise das imagens digitais obtidas das plântulas. Houve medição computadorizada da extensão total, com a soma usual do comprimento do coleóptilo ao comprimento da maior raiz da plântula e, também, não usualmente, ao tamanho de todo sistema radicular. As plântulas foram mensuradas manualmente, visando a comparação com o método em estudo. Os resultados mostraram que a técnica digital possibilita a associação dos dados obtidos no processamento a eventuais diferenças de vigor existentes em lotes de sementes de milho, de maneira similar a outros métodos destinados à avaliação do vigor de sementes da referida espécie.<br>The image analysis has high potential use in seed vigor determination. Associated to the seedlings growing test, this technique is fast, precise and makes possible the dimensional image analysis. The result is the total extension of each seedling quantifying the length of their constituent parts. With the purpose of studying the corn seed lots vigor through the seedlings growing test, using the digital images analysis, the corn seedlings (AG122 genotype) were taken from the germination chamber at the fourth day of development and ordered over a sheet, made with a transparent polyester film, on a scanner surface to the images capture. A routine was developed to process digital images of seedlings into the Scil-Image software. There was a computational procedure to measure the total length, with the usual sum of coleoptile to the main root length of seedling and also, not usually, to all root system. The seedlings were measured manually, seeking comparison with the method in study. The results showed that the digital technique makes possible association of the data obtained in processing to eventual vigor differences existing in corn seed lots, in a similar way to the other methods appointed to seed vigor evaluation by referred species.
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Alves, Fernanda Vieira. "Composição química e qualidade fisiológica de sementes de girassol de plantas submetidas à competição intraespecífica." Universidade Federal de Uberlândia, 2010. https://repositorio.ufu.br/handle/123456789/12139.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>The great number of seeds in the sunflower head and the temporal distribution of its
maturation cause the competition between whorls because of nutritional resources and,
consequently, differences in the seed chemical composition from the head regions. As the
competition among plants in the sowing line can influence seeds nutrient drainage, this
work aimed at evaluating both the chemical composition and the physiologic quality of
sunflower plants seed coming from different regions of the sunflower head and plants
stemming from high, low vigor seeds that partook of intra-specific competition. Three
experiments constituted dealing with seeds coming from one third of the head (peripheral,
median and central) were carried out. The experimental design was in randomized blocks
with four repetitions, each experiment treatment being distributed on a subdivided plot. In
the plots, it was evaluated five proportions of high-vigor seeds placed in the sowing line as
it follows: 0,75 (3A:1B); 0,67 (2A:1B); 0,50 (1A:1B); 0,33 (1A:2B), and 0,25 (1A:3B). In
the subplot, it was evaluated plants stemming from seeds of high and low vigor and two
additional treatments (all plants coming from seeds of high or low vigor, 1A:1A and 1B:1B,
respectively). After that, an analysis relating vigor proportions to the head thirds was made.
It was evaluated the percentage of proteins, lipids, total carbohydrates, ashes, moisture
degree, the weight of a thousand seeds, emergency measures (its initial, ending, and middle
times, emergence and average velocity, uncertainty, synchronicity, time variation
coefficient and emergency) obtained through emergency test in the sand. It concludes that:
a) the proportion of vigor of the seeds in the sowing line interfere in performance of the
plants and in seed quality resultant, being that the plants coming of seeds put in major
proportion in the line, independently of the vigor have major competitiveness; b) the
chemical composition of the sunflower seeds ranged with the position of the seeds in the
head. Higher content of carbohydrates and weight of thousand seed were observed in the
peripheral third, while the higher content of protein and lipids were obtained of the seeds in
the middle third; c) the position of the seed in the head interfered in the variables of
germination. Although sunflower head s third peripheral seeds showed a higher emergency
ignition in the sand, it showed a lower final time and time variation coefficient, besides
being having a higher emergency homogeneity and synchrony. The middle third seeds, on
the other hand, showed low emergency homogeneity and synchrony, being more distributed
in time.<br>O grande número de sementes presentes no capítulo de girassol e a distribuição
temporal da maturação delas geram a competição entre os verticilos por recursos
nutricionais e, logo, diferenças na composição química entre sementes das regiões da
inflorescência. Como a competição de plantas na linha de semeadura pode influenciar
na drenagem de nutrientes para as sementes, este trabalho objetivou avaliar a
composição química e a qualidade fisiológica de sementes de girassol oriundas de
diferentes regiões do capítulo e de plantas-mãe originadas de sementes de alto vigor e
de baixo vigor que sofreram competição intraespecífica. Foram conduzidos três
experimentos constituídos por sementes oriundas dos terços do capítulo (periférico,
mediano e central). O delineamento experimental foi em blocos casualizados com
quatro repetições. Os tratamentos em cada experimento foram distribuídos em parcelas
subdivididas, na quais se avaliaram cinco proporções de sementes com alto vigor
colocadas na linha de semeadura: 0,75 (3A:1B); 0,67 (2A:1B); 0,50 (1A:1B); 0,33
(1A:2B) e 0,25 (1A:3B). Nas subparcelas, foram avaliadas as plantas oriundas das
sementes de cada nível de vigor (alto e baixo) e dois tratamentos adicionais (todas as
plantas oriundas de sementes de vigor alto ou vigor baixo, 1A:1A e 1B:1B,
respectivamente). Depois foi feita a análise relacionando-se as proporções de vigor
avaliadas e os terços do capítulo. Foram avaliadas a porcentagem de proteínas, lipídeos,
carboidratos totais, cinzas, grau de umidade e peso de mil sementes, além das medidas
de emergência (tempos inicial, final e médio de emergência, velocidades média e de
emergência, incerteza, sincronia, coeficiente de variação do tempo e emergência),
obtidas por meio do teste de emergência em areia. Conclui-se que: a) a proporção de
vigor das sementes na linha de semeadura interfere no desempenho das plantas e na
qualidade das sementes resultantes, e as plantas oriundas de sementes colocadas em
maior proporção na linha, independentemente do vigor, têm maior competitividade; b) a
composição química das sementes de girassol variou com a posição das sementes no
capítulo. Maior teor de carboidratos e peso de mil sementes foram observado no terço
periférico, ao passo que maior teor de proteína e lipídeos foi obtido das sementes do
terço central; c) a posição da semente no capítulo interferiu nas variáveis da
germinação. Embora apresentem maior tempo inicial de emergência em areia, as
sementes do terço periférico do capítulo de girassol apresentam menor tempo final e
menor coeficiente de variação do tempo, tendo maior homogeneidade e sincronia de
emergência. As sementes do terço central, em contrapartida, apresentam menor
homogeneidade e sincronia de emergência, sendo mais distribuídas no tempo.<br>Mestre em Agronomia
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Silva, Josué Bispo da [UNESP]. "Testes para avaliar o potencial fisiológico de sementes de beterraba." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/105115.
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silva_jb_dr_jabo.pdf: 199072 bytes, checksum: 14fd74baadfa1ee3eebbb79f63e6a4fa (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA)<br>O uso de testes de vigor é imprescindível na avaliação do potencial fisiológico das sementes produzidas e comercializadas por uma empresa. O trabalho, dividido em duas etapas, teve por objetivo estudar diferentes testes para avaliar o potencial fisiológico de sementes de beterraba. Com base nos resultados, concluiu-se que os testes de EA, EASS-20, EASS-40 e DC podem ser utilizados para avaliar o potencial fisiológico de sementes de beterraba; o uso de soluções salinas apresenta vantagem sobre o procedimento tradicional; o ajuste do TA das sementes no teste de deterioração controlada deve ser feito pelo método do substrato úmido.<br>The use of vigor tests is essential to evaluate the physiological potential of seed lots produced and selled by a company. The work, separated in two stages, aimed to study different vigor tests to evaluate the physiological potential of beetroot seeds. With base in the results, it was concluded that EA, EASS-20, EASS-40 and DC tests can be used to evaluate the physiological potential of beet seeds; the use of solutions presents advantage on the traditional procedure; the adjustment of seed MC in the controlled deterioration test would be done by the method of humid substratum.
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Almeida, Cíntia Borges. "Variabilidade de portaenxertos de pessegueiro: efeitos sobre o crescimento inicial dos seedlings e nos caracteres bioagronômicos das cultivares Chimarrita e Maciel." Universidade Federal de Pelotas, 2013. http://repositorio.ufpel.edu.br:8080/handle/prefix/3013.
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Previous issue date: 2013-03-26<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>As razões que justificam o uso de portaenxertos na fruticultura são a possibilidade de usar cultivares resistentes à pragas e doenças de solo, que induzam maior produção e a adaptação das cultivares copa. Sendo assim, é imprescindível conhecer as características bioagronômicas das diferentes combinações cultivar copa/portaenxerto, a fim de proporcionar melhor produção e qualidade de frutos, e com maior eficiência produtiva. O presente trabalho teve como objetivo avaliar através de caracteres bioagronômicos, o vigor, a produtividade e a qualidade dos frutos de duas cultivares de pessegueiro enxertadas sobre portaenxertos distintos, em condições de cultivo da região de Pelotas/RS. Além disso, pretende identificar a variabilidade de seedlings de portaenxertos de pessegueiro através da influência da
estratificação na germinação, emergência e crescimento inicial das plântulas em casa de vegetação e à campo. Foram realizados dois experimentos, ambos divididos em dois ensaios. Experimento 1- o ensaio 1 foi conduzido a campo com cultivar copa Chimarrita (plantada em 2003) enxertada sobre ‘Okinawa clone 1’, ‘Tsukuba 1’, ‘Capdeboscq’, ‘GF 305’ e ‘Aldrighi’. Foram avaliados diâmetro do tronco e altura das
plantas, número de frutos por planta, produção por planta, massa média dos frutos, produtividade estimada, eficiência produtiva, classificação dos frutos por categoria (I, II e III) e teor de sólidos solúveis. Não registrou-se diferenças significativas por efeito dos portaenxertos quanto ao desenvolvimento vegetativo, porém o portaenxerto ‘Okinawa clone 1’ proporcionou maior rendimento por hectare na cv. ‘Chimarrita’, na região de Pelotas/RS. O ensaio 2 também foi conduzido à campo com a cultivar copa Maciel (plantada em 2005) enxertada sobre ‘Aldrighi’, ‘Indústria’, ‘Okinawa clone 12’, ‘Capdeboscq’, ‘Nemaguard’, ‘Tsukuba 1’, ‘Okinawa clone 1’, e ‘Rubira’. O trabalho foi realizado nas mesmas condições do ensaio 1, com as mesmas variáveis respostas. As plantas quando enxertadas com o portaenxerto ‘Aldrighi’, mostraramse mais produtivas. Com a combinação ‘Maciel’/’Okinawa clone 1’ obteve-se frutos
com maior teor de sólidos solúveis. Experimento 2- o ensaio 1 constou da estratificação a 4ºC, por 60 dias, de sementes de 10 portaenxertos de pessegueiro, para avaliação da porcentagem de germinação. A seguir, realizou-se a semeadura em casa de vegetação, e após 30 dias avaliou-se a porcentagem de emergência e 6 desenvolvimento dos seedlings dos 10 genótipos [‘Umecha’, ‘Tsukuba’ (clones 1, 2 e
3), ‘Okinawa roxo’, ‘Seleção NR-0170302’, Okinawa F3’, ‘Flordaguard’, ‘Okinawa clone11’ e ‘Tsukuba F3’]. Não verificou-se diferenças no percentual de germinação e emergência dos 10 portaenxertos e as plântulas de ‘Okinawa clone 11’ e ‘Tsukuba F3’ foram as que tiveram o menor vigor inicial nos primeiros 30 dias após a emergência, em casa de vegetação. O ensaio 2 foi conduzido a partir de 7 dos 10
portaenxertos do ensaio 1 [Tsukuba (clones 1, 2 e 3), ‘Seleção NR-0170302’, Okinawa F3, Okinawa clone11 e Tsukuba F3], realizado à campo no Centro Agropecuário da Palma de Junho a Janeiro de 2013. Avaliou-se o diâmetro de tronco e altura das plântulas. Pode-se concluir que os seedlings dos portaenxertos ‘Tsukuba 1’ e ‘Seleção NR-0170302’ são os que apresentam o maior vigor inicial a campo, em relação aos demais portaenxertos avaliados.<br>The reasons that justify the use of rootstocks on fruit are the possibility to use to use resistant cultivars of to pests and soil diseases, which induce higher production and adaptation of cultivars Cup. Therefore, it is essential to know the characteristics of different combinations bioorganic scion / rootstock in order to provide improved production and fruit quality and greater production efficiency. This study aimed to
evaluate through bioagronômicos characters, vigor, yield and fruit quality of two peach cultivars grafted on rootstocks distinct growing conditions in the region of Pelotas / RS. Furthermore to identify the variability of seedlings of peach rootstocks through the influence of stratification on germination, emergence and early seedling growth in greenhouse and field. Two experiments were conducted, both divided into two trials. Experiment 1 – test 1 was conducted in the field with scion Chimarrita (planted in 2003) grafted on 'Okinawa clone 1', 'Tsukuba 1', 'Capdeboscq', 'GF 305' and 'Aldrighi'. Were evaluated trunk diameter and plant height, number of fruits per plant, yield per plant, average fruit weight, estimated productivity, production efficiency, fruit classification by category (I, II and III) and soluble solids content. No significant differences were recorded for the effect of rootstocks on the vegetative growth, but the rootstock 'Okinawa clone 1' provided the highest yield per hectare in the cv. 'Chimarrita', in Pelotas / RS. The second test was also conducted on the field with the scion Maciel (planted in 2005) grafted on 'Aldrighi', 'Industry', 'Okinawa clone 12', 'Capdeboscq', 'Nemaguard', 'Tsukuba 1', 'Okinawa clone 1 ', and' Rubira '. The work was performed under the same test conditions 1, with the same response variables. The plants when the rootstock grafted with 'Aldrighi', were more productive. With the combination 'Maciel' / 'Okinawa clone 1' yielded fruit with higher soluble solids content. Experiment 2 - the first test consisted of stratification at 4 º C for 60 days, the seeds of 10 peach rootstocks to evaluate the germination percentage. The following took place seeding in the greenhouse, and after 30 days, the percentage of emergence and development of seedlings of 10 genotypes ['Umecha', 'Tsukuba' (clones 1, 2 and 3), 'Okinawa purple ',' Selection NR-0170302 ', Okinawa F3', 'Flordaguard', 'Okinawa clone11' and 'Tsukuba F3']. No differences were found in the percentage of germination and emergence of the 10 rootstocks and seedlings of 'Okinawa clone 11' and 'Tsukuba F3' were those who had the lowest initial force in the first 30 days after emergence in the greenhouse. Test 2 was conducted from 7 of the 10 rootstocks test 1 [Tsukuba (clones 1, 2 and 3), Selection NR-0170302 ', F3 Okinawa, Okinawa and clone11 Tsukuba F3], held the field at the Agricultural Center 8 Palma June to January 2013. We evaluated the trunk diameter and height of seedlings. It can be concluded that the seedlings of rootstocks 'Tsukuba 1' and 'Selection NR-0170302' are those with the highest initial force field, compared to the other rootstocks evaluated.
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Kamboozia, Jafar. "Seedling vigour in winter grain legumes." Title page, table of contents and abstract only, 1994. http://web4.library.adelaide.edu.au/theses/09PH/09phk152.pdf.
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Hoffmaster, Andrew L. "An Automated System for Seed Vigor Testing Three-Day-Old Soybean Seedlings." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1377872760.
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Lanferdini, Diego. "Influência do vigor inicial e do tempo de armazenamento na qualidade fisiológica de sementes de soja tratadas industrialmente." Universidade Federal de Pelotas, 2017. http://guaiaca.ufpel.edu.br:8080/handle/prefix/4053.
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Previous issue date: 2017-08-09<br>A performance fisiológica das sementes é afetada por diversos fatores dentre
eles o armazenamento, a qualidade inicial do lote e do tratamento químico a que
é submetido. Sendo assim este trabalho teve como objetivo avaliar a qualidade
fisiológica de sementes de duas cultivares de soja submetidas ao
armazenamento após tratamento industrial. O experimento foi conduzido na
Fazenda Sperafico na safra 2014/2015, no município de Sapezal no Mato
Grosso. O delineamento experimental utilizado foi inteiramente casualizado, com
tratamentos dispostos em fatorial 2 níveis de vigor (alto e baixo) em quatro
períodos de avaliação (0, 20, 40 e 60 dias) com três repetições por tratamento.
Os dados foram submetidos à análise de variância e posteriormente, havendo
significância para a interação dos fatores, foram realizados os devidos
desdobramentos, comparação de médias através do teste de Tukey para fator
níveis de vigor e regressão polinomial para o fator período de avaliação, todos a
5% de probabilidade. Com base nos testes realizados conclui-se que em ambas
cultivares, quando utilizando-se de sementes com alto vigor as mesmas não
sofrem decréscimos nos seus níveis de vigor e germinação tanto em ambiente
controlado como em emergência em solo no período de armazenamento.
Quando utilizado de sementes com baixo vigor as mesmas sofreram redução
nos em seus níveis de vigor e germinação em ambas as cultivares, em ambos
os testes de forma acentuada após os 40 dias de armazenamento.<br>The physiological seeds performance may be influenced by several factors,
including the storage, the initial seed quality of the lot and the chemical to which
it is treated. The objective of this work was to evaluate the physiological seed
quality of two soybean cultivars submitted to storage after industrial treatment.
The experiment was conducted at Fazenda Sperafico in the 2014/2015 harvest,
in Sapezal, Mato Grosso. The experimental design was completely randomized,
with treatments arranged in a factorial: 2 levels of vigor (high and low) in four
evaluation periods (0, 20, 40 and 60 days) with three replications per treatment.
The data were submitted to analysis of variance and afterwards, with significance
for the interaction of the factors, the correlation between Tukey's test for factor
strength levels and polynomial regression for the factor evaluation period was
performed. 5% probability. Based on the tests carried out, it can be concluded
that in both cultivars, when using seeds of high vigor, they do not suffer decreases
in their vigor and germination levels, both in controlled environment and in
emergencies in soil during the storage period. When seeds were used with low
vigor, they were reduced in their vigor and germination levels in both cultivars, in
both tests, after 40 days of storage.
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Camu, Isabelle Veronique Marie. "Understanding the mechanism(s) of hydro-priming to improve seed vigour and seedling establishment of Solanum lycopersicum." Thesis, University of Exeter, 2017. http://hdl.handle.net/10871/33211.
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Seeds are very complex and diverse plant organs. Seed germination is the most sensitive stage of plant life and is influenced by various environmental signals including phytohormones, salt, light, temperature and water potential. Seeds have an innate mechanism called dormancy that blocks germination, and plants have developed several dormancy-inducing strategies to optimise the timing of germination. Seed germination vigour is an important factor in crop yield. Seedling vigour is defined as the sum of the seed properties which determine the level of activity and performance during germination and seedling emergence. A poor seed lot can be improved by post-harvest treatment such as hydro-priming as it is used in the seed industry, but the biological mechanism is unknown. The aim of this study is to understand the mechanism(s) of hydro-priming in order to improve seed vigour and seed germination. I set seeds at different temperatures to produce variation in seed vigour and it showed that germination of seeds with low vigour can be improved by hydro-priming. Using LC-IT-ToF/MS I characterised compounds that leach from seeds during hydro-priming, and showed that some of these are putative germination inhibitors. Adding these compounds to the water during hydro-priming showed that the inhibitory effect of these compounds is not the main mechanism that regulates germination. Also, transcriptomic analysis showed that genes involved in OPDA pathway are expressed during hydro-priming as well as during endosperm weakening cap associated genes. I concluded that hydro-priming improves the speed of germination of low temperature set and its efficiency is dependent of activation of metabolic activity.
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Van, Tonder N. C. P., der Westhuizen C. Van, and der Westhuizen R. J. Van. "Interaction effects of effective microorganisms and prolonged storage on germination and seedling vigour of maize, sorghum and sunflower." Journal for New Generation Sciences, Vol 12, Issue 2: Central University of Technology, Free State, Bloemfontein, 2014. http://hdl.handle.net/11462/666.
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Published Article<br>A study involving two incubation experiments and a germination experiment in sandy soil was conducted to determine the influence of Multiplied Effective Micro-organisms (M-EM) that were exposed to different levels of irradiation and temperature fluctuation as well as prolonged storage, on the germination and seedling vigour of maize, sorghum and sunflower. Irrespective of poor handling and/or prolonged storage of M-EM, seed treatment with M-EM improved germination under optimal conditions for all crops compared to the control. Increased planting depths and cold stress were used to create conditions where seed treatment with M-EM may improve germination and seedling growth. Seed treatment with M-EM significantly improved germination and seedling vigour of the stress-tolerant maize cultivar following cold stress. Similar improved seedling vigour results were observed for the stress-tolerant sunflower cultivar at increased planting depth. It was concluded that the beneficial influence of M-EM as a seed treatment was remarkable, even after exposure of M-EM to unfavourable environmental conditions and prolonged storage before application. Further research under field conditions and in different cultivation systems are required before the large scale application of M-EM as seed treatment can be recommended.
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Gurmu, Mulugeta. "The effects of seed vigour and moisture stress on the germination and seedling establishment of wheat and sorghum." Thesis, University of Aberdeen, 1991. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU031802.
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The experiments reported in this thesis assessed vigour differences between seed lots of wheat and sorghum under suboptimal conditions. A vigour assessment for each lot of both species was quantified by calculating a value for the viability equation constant Ki. Imbibition of seed lots at lower water potentials reduced water uptake, radicle and coleoptile emergence and their subsequent extension. Similarly, seeds aged by controlled deterioration also resulted in reduced radicle and coleoptile emergence and growth compared to that of unaged seeds. The critical water potential for radicle emergence, coleoptile emergence and their subsequent extension was lower for sorghum than that required for wheat. In both species coleoptile emergence and its subsequent extension was more sensitive than radicle emergence and extension. Tolerance of desiccation of both species decreased as germination progressed. However, imbibition of seeds for 24 h and drying back to their original moisture content promoted seed invigoration in some cases. Cells from seminal roots of wheat and sorghum were shorter when imbibed in lower water potentials than when they were imbibed at higher water potentials. The high drought tolerant cv (DJ1) showed lower root solute potential than the low drought tolerant cv (IS9). The results discussed in this thesis indicate that the information derived from controlled deterioration might be used as an indicator of planting value under sub-optimal conditions.
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Caldeira, Sidney Fernando. "Conservação, viabilidade e vigor de diásporos e crescimento inicial de mudas de aroeira (Myracrodruon urundeuva Fr. Allem.)." Universidade Federal de São Carlos, 2007. https://repositorio.ufscar.br/handle/ufscar/1598.
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Previous issue date: 2007-10-24<br>The increase of the antropic action on the different forms of
vegetation imposes the necessity to study the forest species, as much as for its conservation,
as for its use in environment and productive plantations. If the species is still widely explored
in function of the quality of its wood and of other types of products, they increase the risks for
its extinction, and the Myracrodruon urundeuva ( aroeira ) is a species that fits in these
aspects. The seed still is the most popular and common form of reproduction of the majority
of the forest species, and also for its "ex-situ" conservation. However, the majority of the
works on storage is conducted in cold or dry chambers, or its combination, of high cost, for
periods around 12 months, and not always they reach the variation of the packages, in relation
to the permeability. The option of keeping the quality of diasporas of "aroeira", deriving of
seeds collection area, in Cuiabá, Brazil, and cheaper conditions to be stored, and of this form,
accessible to more users was evaluated under different forms. In controlled chamber for a
conditioning air device, the viability of diasporas of "aroeira" was conserved up to 30 months
of storage, while the vigor was kept up to six months, independent of the type of packing
used, since the impermeable one, until the total permeate one. In room environment the
viability and the vigor were been reduced, at the age of six months, but in lesser speed, when
the diasporas were conditioned in packing of can and polyethylene bag; at the age of 12
months the deterioration increased and at the age eighteen it was complete. Positive and
significant correlations between the methods of analysis of viability as well as of vigor had
been observed. The test of accelerated ageing presented resulted satisfactory to evaluate the
quality of the diasporas of aroeira , while the tests of electric conductivity and of the diasporas thousand mass had not been adjusted. The evaluation of the initial development of
seedlings, produced from the diasporas stored under different conditions, resulted in lesser
values of height, diameter of collar and total dry substance mass, in relation to produced
seedlings with the diasporas just harvested. However, with the development of the seedlings,
these differences did not remain and presented inferior as well as superior values, in relation
to the previous evaluations. It is possible to keep the viability of diasporas of aroeira , for at
least up to 30 months, and its vigor up to six months, with its storage in controlled chamber.<br>O aumento da ação antrópica sobre as diferentes formas de vegetação,
impõe a necessidade de estudar as espécies florestais, tanto para a sua conservação, como o
seu uso em plantios ambientais e produtivos. Se a espécie ainda é largamente explorada em
função da qualidade de sua madeira e de outros tipos de produtos, aumentam os riscos de sua
extinção, e a aroeira é uma espécie que se enquadra nesses aspectos. A semente ainda é a
forma mais popular e comum de reprodução da maioria das espécies florestais, e também para
a sua conservação "ex-situ". Contudo, a maioria dos trabalhos sobre armazenamento é
conduzida em câmaras frias, secas ou a sua combinação, de alto custo, por períodos em torno
de 12 meses, e nem sempre abrangem a variação das embalagens, quanto à permeabilidade. A
opção de manter a qualidade de diásporos de aroeira, oriundos de área de coleta de sementes,
em Cuiabá, em condições mais amenas e mais baratas de serem armazenadas, e desta forma,
acessível a mais usuários, foi avaliada sob diferentes formas. Em câmara climatizada por um
aparelho condicionador de ar, a viabilidade de diásporos de aroeira se conservou até 30 meses
de armazenamento, enquanto o vigor se manteve até seis meses, independente do tipo de
embalagem utilizada, desde a impermeável, até a totalmente permeável. Em ambiente a
viabilidade e o vigor foram reduzidos, aos seis meses, mas em menor velocidade, quando os
diásporos foram acondicionados em embalagem de lata e em saco de polietileno; aos 12
meses a deterioração aumentou e aos 18 meses foi completa. Foram observadas correlações
positivas e significativas entre os métodos de análise tanto da viabilidade como do vigor. O
teste de envelhecimento acelerado apresentou resultados satisfatórios para avaliar a qualidade
dos diásporos de aroeira, enquanto os testes de condutividade elétrica e da massa de mil
diásporos não foram adequados. A avaliação do desenvolvimento inicial das plântulas, produzidas a partir dos diásporos armazenados sob diferentes condições, resultou em menores
valores de altura, diâmetro do coleto e massa de matéria seca total, em relação às plântulas
produzidas com os diásporos recém colhidos. Contudo, com o desenvolvimento das mudas,
essas diferenças não se mantiveram e apresentaram tanto valores inferiores como superiores,
em relação às avaliações anteriores. É possível manter a viabilidade de diásporos de aroeira,
pelos menos até 30 meses, e o seu vigor até seis meses, com o seu armazenamento na câmara
climatizada.
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Arruda, Natália. "Avaliação da estrutura e do potencial fisiológico de sementes de crotalária por meio de recursos de análise de imagens." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-14032013-131905/.
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A utilização de procedimentos rápidos e confiáveis para análise de sementes é fundamental para a tomada de decisões nas diferentes etapas do processo produtivo e definição do destino dos lotes de sementes. Neste sentido, os objetivos desta pesquisa foram: a) avaliar a estrutura de sementes de crotalária, utilizando raios X para avaliação das partes da semente, identificação de possíveis danos causados por injúrias mecânicas, por percevejo e tecidos deteriorados nas sementes e sua relação com a germinação; b) verificar a possibilidade de utilização do sistema computadorizado de análise de plântulas (SVIS®) para detectar diferenças de vigor entre lotes de sementes de Crotalaria juncea, em comparação com as informações fornecidas por testes tradicionalmente utilizados para a espécie. Foram utilizadas seis lotes de sementes de crotalária do cultivar IAC-KR1, tanto para avaliação da estrutura de sementes quanto para a análise de imagens de plântulas. As análises relativas à morfologia interna das sementes foram realizadas em apenas uma época, no início da pesquisa, ao passo que aquelas relativas ao sistema computadorizado de imagens de plântulas e demais testes de vigor foram realizados em duas épocas, espaçadas de quatro meses. Inicialmente as sementes foram submetidas ao teste de raios X e ao teste de germinação. As plântulas normais, anormais e sementes mortas foram fotografadas e analisadas paralelamente às imagens radiográficas das sementes. Na segunda etapa da pesquisa, os seis lotes foram submetidos a testes de germinação e de vigor (primeira contagem de germinação, envelhecimento acelerado, emergência de plântulas em areia e condutividade elétrica). Para determinação do vigor das sementes por meio do SVIS®, as plântulas foram avaliadas aos três e quatro dias após a semeadura do teste de germinação, sendo obtidos dados referentes ao índice de uniformidade de desenvolvimento, vigor e comprimento de plântulas. Concluiu-se que a análise de imagens de raios X permite identificar danos mecânicos, por percevejo e tecidos deteriorados em sementes de crotalária e relacioná-las com a germinação; o SVIS® é uma alternativa viável para a avaliação do vigor de sementes de crotalária.<br>Fast and reliable procedures for analyzing seeds are fundamental for taking decisions during the different production stages and defining the destination of seed lots. Therefore, the objectives of this study were: a) to study the structure of sun hemp seeds with X-ray to evaluate the seed parts and identify possible damage caused by mechanical injuries, stink bugs and deteriorated tissues and their relation to germination; b) verify the possibility of using a computerized seedling analysis system (SVIS®) to detect differences in vigor between seed lots of Crotalaria juncea, and compare the results with those obtained from vigor tests used for the species. Six lots of the sun hemp cultivar IAC-KR1 were used to evaluate seed structure and also to analyze seedling images. The internal morphology seed was analyzed only at the beginning of the study whereas the computer analysis of seedling images and the other vigor tests were done at two different times, four months apart. The seeds were first submitted to X-ray and germination tests. Normal and abnormal seedlings and dead seeds were photographed and analyzed at the same time as the seed X-ray images. In the second stage of the study, the six lots were submitted to germination and vigor (first germination count, accelerated aging, seedling emergence in sand and electrical conductivity) tests. To determine the seed vigor using the SVIS®, the seedlings were evaluated three and four days after sowing for the germination test, when data on the uniformity development index, vigor and seedling length were obtained. It was concluded that the analysis of X-ray images is efficient for identifying mechanical damage, stink bug damage and deteriorated tissues and allowed to establish an association between their occurrence and germination; the SVIS® is a viable alternative for evaluating the vigor of sun hemp seeds.
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Moliterno, Enrique Alfredo Parachu. "Variabilidade genética e a eficiência de seleção no caráter dormência de sementes em aveia-preta(Avena strigosa Schreb.)." Universidade Federal de Pelotas, 2008. http://repositorio.ufpel.edu.br/handle/ri/1458.
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Previous issue date: 2008-02-28<br>Seed dormancy is a trait shown by a large variety of
weedy plants, which helps the purpose of perpetuating the species through
space and time by delaying germination until specific environmental cues
happen. Black oat, a temperate forage grass, is widely used for pasture and
as a cover crop in minimum tillage systems in Southern Brazil. However,
the largest portion of the seed sown belongs to an old variety, which has no
genetic identity, contributing to the appearance of undesirable agronomic
traits in a crop species such as seed dormancy. This trait is hold
responsible for turning black oat into a potential weedy species in areas
sown to other cool season cereals, such as wheat and barley. Three
methods were used to screen and select for black oat genotypes
expressing low seed dormancy, i.e. screening of lines collected throughout
different agricultural regions of the state of Rio Grande do Sul; subjecting a
specific line of the species to the effects of two chemical and one physical
mutagens and crossbreeding between selected lines and commercial
cultivars of the species. All three methods were undertaken under a
glasshouse environment (without temperature control), and since there are
no known vegetative morphological traits associated to seed dormancy the
procedure consisted on selecting seedlings from non dormant seeds. These
were grown in the glasshouse environment and their progeny seeds tested
for germinability, thus repeating the cycle. Genetic progress was slow for all
three methods and cross breeding resulted the most difficult way for the
creation of new genotypes, as only less than 8% of all pollinated flowers
yielded hybrid seeds. Differences in germinability percentage among seeds
of the first and second selection cycles were largest for the line- screening
method, less for mutant seed phenotypes and minimum for the
crossbreeding method, in which only F1 seeds were tested for germinability.
On average, mutant seed treatments yielded 15% germinability after the first selection cycle, increasing to 20% germinability by the end of the
second selection cycle. The screening of black oat lines yielded an initial
7% germinability, which increased to 36% germinability by the end of the
second cycle. A common trend for all three methods was that seed
germinability was highest during the first half of the standard germination
test period for oat species, which implies that seedling selection was
exercised for two traits simultaneously, i.e. absence of seed dormancy and
seed vigor. The identification of several genotypes producing seeds
expressing both traits increases the opportunity for genetic progress in this
species.<br>A dormência de sementes é um caráter de muitas
espécies de plantas invasoras de culturas agrícolas modernas, a qual tem
por objetivo preservar a multiplicação da espécie através da germinação de
suas sementes ao longo do tempo e o espaço. Aveia-preta é uma
gramínea forrageira temperada muito semeada para produção de forragem
e proteção do solo como cultura de cobertura, em sistemas de plantio
direto. Porém, a maior parte da semente utilizada para semear a espécie
pertence a uma variedade que praticamente não tem sido melhorada desde
sua introdução, produzindo sementes com níveis variáveis de dormência.
Esse caráter tem gerado problemas na área agrícola ocupada por essa
espécie, tornado-a invasora potencial de outras culturas de estação fria.
Com o objetivo de contribuir à melhora do caráter dormência de sementes
quanto de outros de interesse numa espécie forrageira, foram aplicados
três métodos de seleção de genótipos produtores de sementes com baixo
nível de dormência: avaliação de genótipos fixos (linhagens) provenientes
de diferentes regiões edafoclimáticas do estado de RS, indução a mutação
de um genótipo fixo por dois agentes mutagênicos químicos e um físico e
hibridações artificiais entre catorze genitores (linhagens e cultivares
comerciais). Conforme a influência do ambiente num caráter quantitativo
como a dormência de sementes, e o fato de não ter associação conhecida
com caracteres morfológicos vegetativos, a estratégia adotada foi de
multiplicar as sementes de cada tratamento sob ambiente de casa de
vegetação e avaliar sua germinabilidade logo após a colheita. Os
progressos na expressão do caráter de interesse foram lentos para os três
métodos empregados, sendo que a hibridação artificial resultou o método mais difícil desde que o porcentual de sementes hibridas obtidas em
relação ao número de polinizações efetuadas foi inferior a 8%. A diferença
entre a germinabilidade das sementes oriundas do primeiro ciclo de
seleção em relação às seguintes foi mais marcante para as linhagens do
que para aqueles genótipos mutantes. Já, no caso dos híbridos, a
avaliação só abrangeu a geração F1 por causa da baixa quantidade de
sementes produzidas. Enquanto o progresso para o conjunto de
tratamentos com mutagênicos foi relativamente baixo, com germinabilidade
inicial média de 15% e final de 20%, as linhagens iniciaram em média com
7% de germinabilidade e logo do primeiro ciclo de seleção finalizaram a
avaliação com 36% germinabilidade. Um aspecto comum aos três métodos
empregados foi o fato da germinabilidade das sementes ser expressa em
níveis mais importantes na primeira metade do período padrão da análise
de germinação para a espécie. Isso implica em que a seleção de plântulas
foi feita considerando dois caracteres, ausência de dormência e vigor de
sementes em forma conjunta. A obtenção de vários genótipos no presente
experimento produzindo sementes com ambos os caracteres abre boas
perspectivas de progresso genético em aveia preta.
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Lima, Daniel Caio de. "Avaliação do vigor e germinação de sementes de soja a partir da análise de imagens de plântulas." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18152/tde-15042015-104931/.
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A cultura de soja desempenha um papel importante na economia nacional, por isso seria importante o estabelecimento de métodos de testes precisos que pudessem auxiliar na determinação da qualidade das sementes para definição do destino certo de um lote, direcionando-o para plantio ou alimentação. Testes de vigor são testes que levam em consideração a relação entre a semente e o ambiente de semeadura e complementam os resultados de testes de germinação, descrevendo o potencial que um lote de sementes possui para o desenvolvimento de plântulas normais sob um amplo conjunto de condições ambientais. O método clássico para avaliação da germinação e do vigor de sementes baseia-se na inspeção visual das plântulas após um período de germinação sendo um processo demorado e subjetivo, assim, neste trabalho é proposta uma novo método para automatizar a avaliação da germinação e do vigor de um lote de sementes de soja com base no desenvolvimento das plântulas, por meio da análise de imagens digitais. As imagens deste experimento são capturadas por um scanner e depois são submetidas a procedimentos para que se possam extrair as características relevantes para calcular o vigor. Foram avaliados três métodos para segmentar as imagens baseados nos modelos de cor RGB, HSV e imagens geradas pelo resultado de operações matemáticas entre canais dos dois modelos, foram testadas duas metodologias para separar o cotilédone da raiz em plântulas, sendo uma baseada no detector de bordas Canny e outra no detector de cantos SUSAN. Para calcular o índice de vigor, foram utilizadas equações propostas por outro Sako e também foi desenvolvida uma equação baseada no processo de irrigação de solo para análise de uniformidade do comprimento de plântulas. Como resultados obtiveram-se uma média de 91% de cotilédones removidos corretamente das imagens e uma nova equação que melhor representa a uniformidade e elimina a subjetividade humana.<br>Soybean plays an important role in the national economy, so it would be important to establish accurate methods that can assist in determining the quality of seeds to define the right destination to the seed lots, directing it to planting or feeding. Vigor tests are tests that consider the relationship between the environment and seed and complement germination tests results, describing the potential that seed lot has for developing normal seedlings under a wide range of environmental conditions. The classic methods to evaluate seed germination and vigor are based in visual inspection after a germination period, taking much time and it is a subjective task, thus this paper purposes a new method to automatize seed germination and vigor assessment based on seedlings growth using digital images analysis. Images for this experiment are captured by a scanner and then they are submitted to procedures which can extract relevant characteristics to calculate vigor and germination. Three different methods were tested to segmentate images using RGB and HSV color models and images created by results of mathematical operations among arrays of this two color models, having two methodologies to cotyledon from root in seedlings, being one based on Canny edge detector and another based in SUSAN corner detector. To calculate vigor index were tested equations purposed by another authors and also purposes using an equation developed to soil irrigation adapted for assess length uniformity of seedlings. As results we obtained an average of 91% of cotyledons removed properly from images and a new equation that best represents the uniformity of a seed lot and eliminates human subjetivity.
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Corrêa, Plínio Duarte. "Avaliação da morfologia interna e do vigor de sementes de algodão utilizando técnicas de análise de imagens." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-08032018-103644/.
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A avaliação da qualidade de sementes por meio de análise de imagens vem ganhando espaço no mercado sementeiro, devido a sua praticidade, objetividade e rapidez. Assim, o presente trabalho teve como objetivos estudar a utilização do teste de raios X em sementes de algodão do cultivar FM975WS, para avaliação da morfologia interna e a utilização da análise computadorizada de imagens de plântulas (SVIS®) e a sua relação com os testes tradicionais, para avaliação do vigor de sementes. O trabalho foi divido em duas etapas. Na primeira etapa, foram utilizadas imagens radiográficas para avaliar possíveis danos mecânicos, danos por deterioração de tecidos e danos por malformação das sementes e sua relação com a germinação. Na outra etapa, foram utilizados os testes tradicionais para avaliação do vigor de sementes por meio dos testes de primeira contagem de germinação, envelhecimento acelerado, germinação a baixa temperatura, emergência e índice de velocidade de emergência de plântulas em areia, emergência de plântulas em campo e a análise computadorizada de plântulas. Concluiu- se que a análise de imagens, utilizando o teste de raios X, é eficiente na avaliação da morfologia interna de sementes de algodão, com identificação de suas partes internas e na avaliação de danos causados nas sementes, entre eles, danos por deterioração de tecidos, danos por malformação da semente e danos mecânicos, os quais permitem relacionar a ocorrência dos mesmos com a germinação das sementes e que a utilização do SVIS®, como uma técnica de análise computadorizada de imagens de plântulas, é uma alternativa para avaliação do vigor de sementes de algodão.<br>The evaluation of the physiological quality of seeds by means of image analysis has been gaining space in the seed market due to its practicality, objectivity and speed. The objective of this study was to study the use of the X-ray test in cotton seeds of the cultivar FM975WS, to evaluate the internal morphology and the use of the computerized analysis of seedlings images (SVIS®) and its relation with the traditional tests to evaluate seed vigor. The work was divided into two stages. In the first stage, radiographic images were used to evaluate possible mechanical damages, damages due to deterioration of tissues and damages due to seed malformation and its relation with germination. In the other step, the traditional tests were used to evaluate the vigor of seeds by means of tests of first count of germination, accelerated aging, germination at low temperature, emergence and speed index of emergence of seedlings in sand, emergence of field seedlings and computerized analysis of seedlings. It is concluded that the image analysis, using the X-ray test, is efficient in the evaluation of the internal morphology of cotton seeds, with identification of its internal parts and in the evaluation of damages caused to the seeds, among them damages due to tissues deterioration, damage due to seed malformation and mechanical damages, which allow to relate their occurrence to the germination of the seeds and the use of SVIS®, as a technique of computerized analysis of seedlings images, is an alternative for evaluating the vigor of cotton seeds .
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Kibret, Kidist Bogale [Verfasser]. "Systems biological analysis of seedling vigour and osmotic stress tolerance in oilseed rape (Brassica napus L., Brassicaceae) / Kidist Bogale Kibret." Gießen : Universitätsbibliothek, 2017. http://d-nb.info/113657008X/34.
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Tung, Nguyen Chau Thanh [Verfasser]. "Integrated Genetic and Metabolomic Analysis of Seed Germination and Seedling Vigour in Oilseed Rape (Brassica napus L.) / Nguyen Chau Thanh Tung." Gießen : Universitätsbibliothek, 2019. http://d-nb.info/1190559676/34.
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Javorski, Maicon. "Utilização de técnicas de análise de imagens para avaliação da morfologia interna e do vigor de sementes de sorgo." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-30092016-180030/.
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A análise de imagens com a utilização de raios X em sementes e análise computadorizada de plântulas são técnicas eficientes na avaliação da qualidade de sementes de diversas espécies, constituindo-se em métodos de rápida resposta, com metodologias de simples execução e reprodução. Assim, foi proposto com a presente pesquisa avaliar metodologias que visam relacionar a morfologia interna de sementes de sorgo com seu potencial fisiológico por meio da análise de imagens radiografadas de sementes e computadorizadas de plântulas. Para tanto, foram utilizadas sementes do híbrido 50A70, representado por dez lotes. O estudo foi realizado em duas etapas, em que a primeira consistiu no uso de imagens radiografadas para relacionar a morfologia interna das sementes e sua germinação e a segunda consistiu na avaliação do vigor das sementes por meio dos testes de primeira contagem de germinação, envelhecimento acelerado, de frio, de emergência e velocidade de emergência de plântulas em areia, emergência de plântulas em campo e o uso do sistema computadorizado de imagens de plântulas (\"Seed Vigor Image System\" - SVIS®) aos dois e três dias após a semeadura do teste de germinação, para detectar diferenças de vigor das sementes armazenadas durante quatro meses. Concluiu-se que o teste de raios X é eficiente na identificação de danos por deterioração de tecidos, danos mecânicos, danos por malformação e danos por insetos, possibilitando estabelecer a relação entre o dano observado e o prejuízo causado para a germinação. A análise computadorizada de plântulas aos três dias de idade é uma alternativa segura para detectar diferenças de vigor entre os lotes.<br>Image analysis techniques using X-rayed seeds and computerized analysis of seedlings are considered efficient to evaluate the seed quality of various species, with a fast response and methodologies that are easy to implement and reproduce. Thus, this research aimed to evaluated methodologies that associate the internal morphology of sorghum seeds with their physiological potential via radiographed images of seeds and image processing of seedlings. Ten seed lots of the sorghum hybrid 50A70 were used in the study. The study was conducted in two phases; the first involved the utilization of radiographed images of seeds to associate their internal morphology with germination. The second consisted evaluation of vigor using first count germination, accelerated aging, cold test, emergence and speed of emergence in sand, seedling emergence in field and computerized seedling image analysis (\"Seed Vigor Image System - SVIS®\"), the seedlings were evaluated two and three days after sowing for the germination test, in order to detect variations in the seed vigor among the lots, during four months of storage. The results allowed to conclude that the X-ray test is effective in identifying damage tissue deterioration, mechanical damage, malformation damage and insect damage, enabling to establish a relationship between the observed damage and the negative effect on germination. Computerized analysis of three-day-old seedlings consists in a feasible method to detect differences in the seed vigor among the lots.
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Leeks, C. R. F. "Determining seed vigour in selected Brassica species." Lincoln University, 2006. http://hdl.handle.net/10182/1274.
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Variables for the accelerated ageing (AA) test, methods for reducing fungal contamination during the AA test, using the conductivity test as a vigour test, the effect of seed size on seed vigour and the relationship between laboratory test results and field perfonnance in selected Brassica spp were investigated. In the first experiment, three seed lots of turnip rape hybrid (B. rapa x campestris), turnip (B. campestris) and forage rape (B. napus); and seven seed lots of Asian rape (B. napus), six seed lots of Asian kale (B. oleraceae var. alboglabra L.) and five seed lots of choisum (B. rapa var. pekinensis) with germinations above 90% were aged at two different temperatures (41 and 42°C ± 0.3°C) and three ageing times (24, 48 and 72 ± 15 minutes). The second experiment was divided into three sections. In the first, the same seed lots and species were aged at one temperature (41°C) and time (72 h), but either 40 ml of saturated salts; KCl (83%RH), NaCl (76%RH), NaBr (55%RH); or distilled water (96%RH) were used as the ageing solutions. In the second, one turnip rape hyprid seed lot was aged at three temperatures (41, 42 and 45°C) and two times (72 and 96h), again using the three saturated salts and distilled water as ageing solutions. In the third, three turnip rape hybrid seed lots and three Asian kale seed lots were surface sterilised (1 % sodium hypochlorite) prior to ageing at one temperature (41°C) and time (72 h). In the third experiment, the same species and seed lots used in experiment one at their original seed moisture content (SMC) were tested for conductivity after soaking in deionised water for 4, 8, 12, 16, 20 and 24 h. They were then re-tested after the SMC had been adjusted to 8.5%. In the fourth experiment, three seed lots of forage rape and three seed lots of Asian kale were graded into three seed size categories; large (retained on a 2.0 mm screen), medium (retained on a 1.7 mm screen) and small (passed through a 1.7 mm screen). Graded seeds were then tested for standard germination, AA (41°C/48 h) and conductivity (measured at 16 and 24 h). In the final experiment, the relationships between laboratory tests for the six species (each consisting of three seed lots), field emergence from three sowings, and cold room emergence were evaluated. Both time and temperature influenced post-AA germination. Increasing the ageing period from 48 to 72 hours at 41°C, and 24 to 48 hours at 42°C resulted in decreased mean germination percentage for all species but not always clear separation of seed lots. While there were sometimes few differences between ageing at 41°C and 42°C, the former is preferred because it is already the temperature used for other species. For Asian rape, choisum and turnip, the previously recommended testing conditions of 41°C/72 h provided good seed lot separation, but for Asian kale and turnip rape hybrid, AA testing at 41°C/48 h provided better results. Seed moisture content after ageing ranged from 29-37% depending on species. Fungal growth on seeds during the ageing period appeared to reduce post-ageing germination in some seed lots . Substituting saturated salts for distilled water did not stress seed lots in the AA test, due to the lowered RH%, the exception being seed lots 1210 and 1296. For forage and Asian species, seed lot germination mostly remained above 90% when aged for 72 h at lowered RH%. Increasing the ageing duration from 72 to 96 hours resulted in some decreases in post-AA germination but no clear separation of seed lots. Surface sterilising the seeds prior to the AA test resulted in a lower incidence of contaminant fungi which was associated with a lower percentage of abnormal seedlings. The conductivity test was mostly able to identify vigour differences among forage and Asian vegetable brassica seed lots. Differences in conductivity readings were observed among seed lots in all species. Increasing the period of imbibition resulted in increased conductivity from most seed lots but radicle emergence occurred after 16-20 h of imbibition. Variation was observed in the time to reach 95% maximum of the imbibition curve for most species. Conductivity readings at 16 h would avoid possible influences of radicle emergence on results. Adjusting the SMC to 8.5% resulted in reduced variation in conductivity among replicates of seed lots, due to a reduction in imbibition damage. Seed size had a significant effect on both post-AA germination and conductivity results. In forage rape, large size seeds had higher post-AA germination cf. medium cf. small size seeds. In Asian kale, large size seeds had higher post-AA germination compared with small size seeds. For both forage rape and Asian kale, large size seeds had lower conductivity readings cf. small size seeds. The correlation analyses demonstrated significant relationships between AA testing and field emergence parameters (percentage emergence, emergence index and emergence rate). Significant relationships were also observed between conductivity testing and these field emergence parameters. Based on the correlation analysis, AA testing at 41°C/48 hand/or 42°C/48 h could be recommended to be used as an AA test for turnip and Asian rape; and 41°C/48 hand/or 41°C/72 h for Asian kale and choisum. Based on the correlation analysis, conductivity testing at 16 h can be used to predict the field emergence potential of forage and Asian vegetable seed lots. Vigour tests were consistently able to provide better indicators of field perfonnance than the standard germination test, although these relationships did vary with the different field sowings.
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Bates, Sarah L. "Impact of feeding by the western conifer seed bug, Leptoglossus occidentalis (Heidemann) (Hemiptera: Coreidae), on yield, seed storage reserves and seedling vigour in Douglas-fir." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ51294.pdf.
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Moot, Derrick J. "Harvest index variability within and between field pea (Pisum sativum L.) crops." Lincoln University, 1993. http://hdl.handle.net/10182/1285.
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The association between individual plant performance and seed yield variability within and between field pea crops was investigated. In 1988/89 six F8 genotypes with morphologically distinct characteristics were selected from a yield evaluation trial. Analysis of the individual plant performance within these crops indicated an association between low seed yields and the location and dispersion of plant harvest index (PHI) and plant weight (PWT) distributions. The analyses also showed there was a strong linear relationship between the seed weight (SWT) and PWT of the individual plants within each crop, and that the smallest plants tended to have the lowest PHI values. A series of 20 simulations was used to formalize the relationships between SWT, PWT and PHI values within a crop into a principal axis model (PAM). The PAM was based on a principal axis which represented the linear relationship between SWT and PWT, and an ellipse which represented the scatter of data points around this line. When the principal axis passed through the origin, the PHI of a plant was independent of its PWT and the mean PHI was equal to the gradient of the axis. However, when the principal axis had a negative intercept then the PHI was dependent on PWT and a MPW was calculated. In 1989/90 four genotypes were sown at five plant populations, ranging from 9 to 400 plants m⁻². Significant seed and biological yield differences were detected among genotypes at 225 and 400 plants m⁻². The plasticity of yield components was highlighted, with significant genotype by environment interactions detected for each yield component. No relationship was found between results for yield components from spaced plants and those found at higher plant populations. The two highest yielding genotypes (CLU and SLU) showed either greater stability or higher genotypic means for PHI than genotypes CVN and SVU. Despite significant skewness and kurtosis in the SWT, PWT, and PHI distributions from the crops in this experiment, the assumptions of the PAM held. The lower seed yield and increased variability in PHI values for genotype CVN were explained by its higher MPW and the positioning of the ellipse closer to the PWT axis intercept than in other genotypes. For genotype SVU, the lower seed yield and mean PHI values were explained by a lower slope for the principal axis. Both low yielding genotypes were originally classified as having vigorous seedling growth and this characteristic may be detrimental to crop yields. A method for selection of field pea genotypes based on the PAM is proposed. This method enables the identification of weak competitors as single plants, which may have an advantage over vigorous plants when grown in a crop situation.
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Mohamed, Ahmed Mahmoud. "Emergence, seedling vigor, and stand establishment of pearl millet as affected by mesocotyl elongation and other seed and seedling traits." 1985. http://hdl.handle.net/2097/27505.
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Wu, Chun-Wei, and 吳俊偉. "Applying Non-destructive Techniques to Evaluate the Nitrogen Status, Irrigation Index, and Seedling Vigor for Star Cluster (Pentas lanceolata)." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/18795151614220977527.
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博士<br>國立臺灣大學<br>園藝暨景觀學系<br>104<br>This project is using ornamental herbaceous star cluster (Pentas lanceolata) as the experimental plant materials. The chlorophyll fluorescence (ChlF, e.g., the effective photochemical quantum yield of PSII, ∆F/Fm’; photochemical quenching, qP), reflectance spectra and vegetation indices used to build up a realtime evaluation system for leaf nitrogen (N) concentration, N demand timing for fertilizer, leaf water potential (WP), irrigation timing and seedling vigor (SV). The system will provide suitable sugestions for plant material selection and cultivation management model and could improve landscaping qualities and functions.
The objective of nitrogen (N) study was to predict the N demand timing for fertilizer application through ChlF, soil-plant analysis development (SPAD), and normalized difference vegetation index (NDVI). The tested plants were grown in potting soil by weekly irrigation with five concentrations (0, 4, 8, 16, and 24 mM) of N for 30 d. These five N application levels corresponding to the N concentration in leaves of tested plants were 2.62%, 3.48%, 4.00%, 4.23%, and 4.69%, respectively. The trends and rates of increase from 0 to 8 mM N treatments to its peak in Dickson’s quality index (DQI), above ground dry weight (DW), total DW, flowering rate, ∆F/Fm’, and qP were all similar to SPAD, NDVI, and the maximum photochemical quantum yield (Fv/Fm) indices. Consistent and strongly high correlations (R2 = 0.60 to 0.85) were observed among leaf N concentration (%) and SPAD, NDVI, ∆F/Fm’, and above-ground DW. With validation of these vegetation indices, leaf SPAD, NDVI, and ∆F/Fm’ are shown to be accurate and non-destructive predictors of leaf N concentration and can be used to accurately estimate N-solution irrigation timing for P. lanceolata. Therefore, the saturation point of plant N irrigation is recommended when leaf N concentration, SPAD, NVDI, and ∆F/Fm’ ratio are 4.00%, 50.68, 0.64, or 0.137, respectively.
The objective of moisture study was to use non-destructive measurements as the precise irrigation indices. Drought stress was imposed on plants for 0, 3, 5, 7, 12, and 16 days by withholding water. Measurements were conducted on the third leaf counted from the apex (upper-leaves) and the third leaf from the bottom. Within the range of soil water content (WC) from 10 to 45%, leaf WP, soil WC, soil matric potential (MP), ChlF, photochemical reflectance index (PRI), adjusted normalized difference vegetation index (aNDVI) and the reflectance (R) at 1950 nm (R1950) were measured. Results show that the plants reached the temporary wilting point exhibited –3.87 MPa for leaf WP, and the maximal fluorescence yield of the light adapted state (Fm’) ratio of upper-to-lower leaves was 1.7. When the Fm’ ratio was 1.3, which corresponded to lower leaf WP < –2.27 MPa, soil WC < 21%, MP < –20 kPa, PRI < 0.0443, aNDVI < 0.0301, and R1950 > 8.904, it was time to irrigate. In conclusion, the Fm’ ratio of upper-to-lower-leaves is shown to be a non-destructive predictor of leaf WP and can be used to estimate irrigation timing.
The objective of quality study was to use the non-destructive measurement of ChlF (such as ∆F/Fm’ and qP) and leaf area index (LAI) as SV indices. Plants were grown in potting soil under nature sunlight for 120 d. Plants were separated into 5 root growth potential (RGP) groups based on the number of new roots, and morphological and physiological parameters were also separated into those same levels. The trends and rates of increase from levels 1 to 5 in DQI, LAI, total dry weight, ∆F/ Fm’, and qP were all similar to the RGP index. Although RGP and DQI are frequently used as indices for SV, these measurements are time-consuming and require sample destruction. Consistent and strongly high correlations (R2 =0.59 to 0.93) were observed among DQI and LAI, ∆F/Fm’, and LAI × (∆F/Fm’), demonstrating the applicability of these indices for measuring SV in star cluster. In particular, LAI × (∆F/Fm’) was predicted using multiple variables from validation datasets, predictions were compared to actual DQI and RGP values for star cluster, and SV indices were predicted. Therefore, LAI × (∆F/Fm’) can replace DQI and RGP in the non-destructive estimation of SV.
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Friesen, Glenn Mark A. "Native grasses : improving the seedling vigor and seed production of blue grama (Bouteloua gracilis) and prairie junegrass (Koeleria macrantha) ecovars (TM)." 2003. http://hdl.handle.net/1993/7819.
Full textAbstract:
Interest continues to grow in the utilization of native grasses for conservation, reclamation, Conservation Reserve Programs (CRP), right-of-ways, and wildlife habitat across North America. However, difficulty in establishment and limited availability of adapted seed sources has constrained the use of native grasses. The objectives of this study were to assess the effects of seeding rate, phosphorous fertilizer, Penicillium bilaii and soil texture on the establishment of blue grama and prairie junegrass ecovars TM, to examine the morphological distinctness and uniformity of a Manitoba blue grama ecovarrM, and to determine the potential for protection of this ecovar TM under the Plant Breeders' Rights Act of Canada. Blue grama and prairie junegrass row densities increased when seeding rate was doubled in a controlled environment; however seedling establishment as a percentage of seed sown decreased. Neither species responded to in-furrow P fefiilizer, fungal inoculant treatment, or a liquid foliar application of N. Soil type was the most important treatment for increasing establishment success, with the sandy loam providing the highest establishment rates and largest plants for both blue grama and prairie junegrass. The potential for the Manitoba blue grama ecovar TM to qualify for protection under the PBR Act of Canada was assessed as good...
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Schmidt, Daria Helene. "An investigation of the effects of endosperm type on pericarp thickness, seed leachate electrolyte conductivity, and seedling vigor in sweet corn inbreds." 1987. http://catalog.hathitrust.org/api/volumes/oclc/16164009.html.
Full textAbstract:
Thesis (M.S.)--University of Wisconsin--Madison, 1987.<br>Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 103-108).
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Reinke, Russell Frederick. "Genetic improvement of seedling vigour in temperate rice (Oryza sativa L.)." Phd thesis, 2000. http://hdl.handle.net/1885/148126.
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Hung, Chien-Cheng, and 洪健誠. "Dissecting the Genetic Architecture of Seedling Vigour in Oats (Avena sativa L.) Using Genome-Wide Association Analysis." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/qf7mz4.
Full textAbstract:
碩士<br>國立臺灣大學<br>農藝學研究所<br>107<br>Oats (Avena sativa L.) rank the seventh cereal crop in the world in the term of production and cropping area, and are also an important forage crop for temperate, subtropical to tropical regions. Under an extensive management, strong seedling vigour is an important agronomic trait to assure a better weed competition at the early stage, and consequently a higher yield of biomass. However, there were few oat study that research oat seedling vigour. In this study, we conducted genome-wide association analysis based on 1,028 diverse oat accessions, including 650 cultivated elite oat accessions from Collaborative Oat Research Enterprise (CORE) and 378 oat landraces from USDA National Small Grains Collection (NSGC) in order to explore the genetic architecture of oat seedling vigour. In addition to traditional cross-sectional studies which assessed the phenotypes of interest at discrete time points, functional modeling was also used to estimate parameters related to the growth dynamics of oat seedlings. We detected 66 and 39 quantitative trait loci (QTL) in CORE and NSGC, respectively. Most of the QTL detected by cross-sectional study were associated with the time points at the first leaf stage (6-12 days after transplantation). QTL of similar traits were located on the homeologous linkage groups. QTL detected on growth parameters obtained using model fitting were also located on several homeologous linkage groups, but the genetic positon were different from those identified using cross-sectional traits. Two sets of homeologs of interest were identified: Mrg09, Mrg20, Mrg21 and Mrg05, Mrg06, Mrg24, which were not only associated to plant height, but also to seedling weight and growth parameters. In addition, those homeologs have been mapped previously for heading date, plant height after heading, or different plant defense responses. Comparing sequences of trait-associated marker with sequences from other cereal species showed that some markers were associated with seedling vigour related genes. Therefore, we believe that these two sets of homeologs merit further work to better understand seedling vigour in oats.
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Li, Sing-Chung, and 李信昌. "Vigour analysis of accelerated aging: Cloning and characterization of a RNA helicase from the viable seedlings of aged mung bean." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/64712524730592990793.
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博士<br>國立臺灣大學<br>農業化學研究所<br>89<br>Storage of seeds under adverse conditions results in the production of "aged "seeds exhibiting reduced grain viability and vigour. The precise causes of seed vigour loss and recovery are still unknown. In order to answer these questions, acceleratedly aged mung bean (Vigna radiata) seeds were used to investigate aging of mung bean seeds at various stages by incubating mung bean seeds at different temperature and relative humidity for various time intervals. The acceleratedly aged seeds exhibited a sigmoidal germination (%)-versus-time curve comparable to the theoretical natural aging curve. Accelerated aging significantly inhibited seed germination and seedling growth, resulting in an increase of the conductivity of seed exudation, decrease in viability and vigor, and higher ethylene production.
A differentially expressed 1.2 kb cDNA fragment was isolated from imbibed acceleratedly aged seeds using mRNA differentially display technique. We obtained a full-length cDNA, named VrRH1 (Vigna Radiata RNA Helicase 1), by RACE method based on the 1.2 kb sequence. VrRH1 contains an open reading frame of 2139 bp encoding a protein of 713 amino acids and has seven highly conserved motifs including the DEAD-box as in the case of other plant RNA helicases. VrRH1 was sub-cloned into an expression vector pET-28b (+), over-expressed in E. coli BL 21 and purified by a Ni2+-Agarose column. The expressed protein showed double-stranded RNA unwinding and ATPase activities. Either ATP or dATP is required for the unwinding activity, indicating that VrRH1 is an ATP/dATP-dependent RNA helicase. The ATPase of VrRH1 has pH and temperature optima at 8.5 and 45℃, respectively. The ATPase activity of VrRH1 was not stimulated by the presence of synthetic polynucleotides.
Northern blot analysis was performed using the 1.2 kb cDNA as a probe to analyze the expression of VrRH1（VrRH） mRNA in aged and non-aged mung bean seeds. The expressions of VrRH1 in 9-d-aged seedlings are higher than control seedlings. In different aging treatment, VrRH1 has the highest expression level in 12-d-aged seedlings. Besides, imbibed aged-seeds with longer axis showed higher level of VrRH1（VrRH）expression.
Northern blot analysis of VrRH1 transcripts in different parts of mung bean showed that axis had higher expression than cotyledon using the full-length cDNA as a probe. There was a little amount of VrRH1 transcripts in newborn leaves, mature leaves and flowers. After accelerated aging treatment, mung bean seeds were imbibed for 16 to 32 hours and the expressions of VrRH1 were analysed at various time intervals of imbibition. The amount of VrRH1 transcripts reached a maximum in 24-hour-imbibed seeds. The accumulation of VrRH1 transcripts was shown to correlate the appearance of 25S and 18S rRNAs in the imbibed aging mung bean seeds. The results suggest that VrRH1 may play a role in the viability of mung bean seeds. It was also shown that seeds obtained from 9-d-12-h plants survived better than the control seeds.
Purified His-VrRH1 was used as the antigens to prepare antisera for immunological studies. VrRH1 proteins were immunolocalized in longitudinal sections from 3-day- germinating accelerated aged seeds. Preliminary results show that VrRH1 proteins were expressed in the shoot apical meristem (SAM) of mung bean seedlings. We suggest that VrRH1 may play a role in regulating the growth and development of mung bean seedlings. Identification of the natural substrate of VrRH1 may provide further insight into its physiological function. Attempts were also made to isolate the native protein of VrRH by ammonium sulfate precipitation and cation exchange chromatography. The partially purified native VrRH had ATPase activity.
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Siu, Ting-Rong, and 許庭榮. "Studies on Germination Condition, Seedling Evaluation and Vigour Test of Great Burdock (Arctium lappa L.) Seeds, and the Influence of Temperature on the Main Root Growth." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/01246917494033634116.
Full textAbstract:
碩士<br>國立臺灣大學<br>農藝學系<br>85<br>Three main great burdock (Arctium lappa L.)varieties,
including 12 seed lots ,were used to conduct a serial
experiments. The purposes of these studies wereto investigate
the optimum germination conditions in standard germination test,
seedling evaluation, the first and final time of investigation,
accuracy ofTTC and conductivity testing for seed viability and
the influence of temperat--ure on main root development of great
burdock. Results of the experiments we--re summarized as
follows: 1. Germination test using 5 seed lots
of great burdock was proceeded at const--ant temperature between
4℃ and 43℃, divided into 14 levels, on two way the--rmo-
gradient plate. According to the linear relationship between 50%
germina-tion rate (y) and temperature (x), a regression equation
y = -0.0515+0.017x, R*R = 0.9975 was obtained. In the regression
model, the base (minimum) tempera--ture for germination was 3.03
℃. The maximum temperature for germination was higher than
37℃. The optimum temperature for germination was 22-28℃ for
rad--icle emergence or 25℃ for standard germination. The
thermal time of physiol--ogical germination and normal seedling
germination was ranged from 49.5 to 64.1℃d and from 208.9 to
278.2℃d respectively.
2. Germination test of 5 and 8 seed lots was performed under
several combinat--ions of germination conditions, such as (1)
temperature treatments including 30/20, 25/15, 35, 30, 25, 20
and 15℃; (2) light treatments including 8 hoursof light and
dark; (3) substratum treatments including top of paper,
between paper, rolled paper and in sand methods; and (4) seed
pretreatments with or w--ithout 24 hours of imbibition in water.
Results showed that the most suitablegermination conditions were
30/20 or 25℃, and theest substratum condition wastop of paper
method. Concurrently, we suggest to imbibe the seeds for 24
hoursin water before incubation to break dormancy and promote
germination. In addi--tion, the germination test requires light
for promoting germination, and thelight is also favorable for
seedling evaluation.
3. In seedling evaluation, a normal seedling of great burdock
can be defined by the following characteristics: intact root
system with one primary root (r--adicle) of no bifurcation, no
observed decay or tightly twisted structure onhypocotyl, and
cotyledons completely emerged from seedcoat but with no
primaryinfection. When primary roots have bifurcation or
crack, secondary roots can not be listed within the cognizance.
4. In germination test under the optimum germination
conditions, according to the variation rate of accumulated
normal seedling germination, the first and final investigated
time were the 11th and 18th day after incubation respectiv--ely.
5. From 11 seed lots of great burdock, including 1100 grains,
TTC staining di--agrams were divided into 10 classes. Based on
RMS method, the model of TTC s--taining diagrams for living
great burdock seeds could further be divided into5 classes. A
significant positive correlation appeared between the rate of
ge--rmination predicted by the judgement rule in TTC test and
the real rate of g-ermination (r=0.9945). 6. In the viable
test, the electrical conductivity of 11 seed lots of great b-
urdock after 8-16 or 16-24 hours of imbibition was significantly
negatively c--orrelated with the rate of germination.
7. During the great burdock cultivation period of the phytotron
under 5 tempe--rature conditions including 15/13, 20/15, 25/20,
30/25 and 35/30℃, the resu--lt showed that the optimum
temperature for the best development for leaves a--bove ground
and main roots under ground were 25/20℃ and 20/15℃
respectively.Thus, with respect of the increasing harvest
proportion of great burdock, theoptimum temperature during the
cultivated period is 20/15℃.
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Xu, Ting-Rong, and 許庭榮. "Studies on Germination Condition, Seedling Evaluation and Vigour Test of Great Burdock (Arctium lappa L.) Seeds, and the Influence of Temperature on the Main Root Growth." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/86446062126563571681.
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