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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Genome analysis and genetic mapping of restorer loci in raphanus

Bett, Kirstin Elizabeth 01 January 2001 (has links)
Genetic variation exists in <i>Raphanus</i> that could be of use to <i>Brassica</i> breeders. Of particular interest is the Ogura system of cytoplasmic male sterility (CMS) which has been worked on extensively in a <i>Brassica napus</i> background. Problems have been experienced in <i>B. napus</i>restorer lines due to the inheritance of a large segment of <i>Raphanus</i> chromosome containing the fertility restoring locus. This restorer introgression is located on the <i>Brassica</i> C genome making it only of use for <i>B. napus</i> and not for <i>B. rapa</i> or <i>B. juncea</i>. This thesis describes the development of the materials necessary for the introgression into the <i>Brassica</i> A genome of a defined segment of <i>Raphanus</i> chromosome containing a restorer locus. Defined genetic stocks of <i>Raphanus</i> were developed that contained specific loci controlling restoration of Ogura CMS. This material was used to develop populations segregating for specific restorer loci. Extensive RFLP maps of three <i>Raphanus</i> populations were developed and aligned, resulting in a robust consensus map of the entire <i>Raphanus</i> genome. Three restorer loci were accurately mapped on three separate linkage groups. The segment of <i>Raphanus</i> that is implicated in the restoration of Ogura CMS in a <i>B. napus</i> restorer line developed by INRA was identified and it did not correspond to any of the regions containing the three mapped restorer loci, suggesting the presence of more restorer loci in <i>Raphanus</i>. Comparative mapping between the <i>Raphanus</i> genome map and previously generated <i>Brassica</i> A genome RFLP maps demonstrated large regions of collinearity between segments of chromosomes of the two species. Preliminary examination of the two genome maps suggest they contain essentially the same overall genetic content but with large segments of the genomes rearranged with respect to each other. Likely sites of <i>Raphanus</i> restorer introgression into the <i>Brassica</i> A genome were predicted. Trigenomic tetraploids were developed in which pairing and recombination between homoeologous segments of <i>Raphanus</i> and <i>Brassica</i> A chromosomes should result. Progeny of these individuals will allow an assessment of the pattern and extent of recombination that occurs between the chromosomes of the <i>Raphanus</i> and <i>Brassica</i> A genomes and should lead to the development of 'B. napus' lines carrying Ogura CMS restorer alleles from <i>Raphanus</i>.
22

Plant Age Affects the Long-term Growth Responses to Reduced Total Pressure and Oxygen Partial Pressure

Wehkamp, Cara Ann 14 September 2009 (has links)
Fundamental to the future of space exploration is the development of advanced life support systems capable of maintaining crews for significant periods without re-supply from Earth. Bioregenerative life support systems harness natural ecosystem processes and employ plant photosynthesis and transpiration to produce food, supply oxygen, and regenerate water while consuming carbon dioxide. Proposed Lunar and Martian exploration has prompted interest into the effects of hypobaria on plant development. Reduced atmospheric pressure conditions will reduce the pressure gradient between the structure and the local environment thereby decreasing the engineering requirements, leakage and mass required to construct the growth facility. To establish the optimal conditions for reduced pressure plant growth structures it is essential to determine the atmospheric pressure limits required for plant development and growth. Due to its physiological importance, oxygen will compose a significant portion of this atmosphere. The effects of reduced atmospheric pressure and decreased oxygen partial pressures on plant germination, growth and development were assessed in the University of Guelph’s hypobaric plant growth chambers. Treatments included a range of total pressures from 10 to 98 kPa and oxygen partial pressures from 2 to 20 kPa. Results demonstrated that reduced atmospheric pressure had minimal effect on plant growth, net carbon exchange rate and transpiration if the physiologically important gases including carbon dioxide, oxygen and water vapour, were maintained above threshold levels. The reduction of oxygen partial pressures below 7 kPa had drastic consequences across all atmospheric pressures with poor germination, seedling establishment and growth. It is evident that the response of plants grown at reduced pressures from young seedlings differs from that of older plants that were established at ambient conditions and then subjected to the atmospheric adjustment. The young plant tissues adapt in response to the extreme conditions and maintain productivity despite the limited atmosphere. / Natural Science and Engineering Research Council, Canadian Space Agency, Ontario Graduate Student Program, Canadian Foundation for Innovation, Ontario Innovation Trust
23

Valor nutritivo, pela Tilápia do Nilo, do farelo de nabo forrageiro

Santos, Vivian Gomes dos [UNESP] 06 March 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-03-06Bitstream added on 2014-06-13T18:48:01Z : No. of bitstreams: 1 santos_vg_me_botfmvz.pdf: 160598 bytes, checksum: 2fe58f8db5442f8ac8dc644c76ac3c0a (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / Várias oleaginosas estão sendo estudadas para a produção de biocombustíveis. O processamento do grão para a obtenção do óleo resulta numa diversidade de subprodutos, entre eles o farelo de nabo forrageiro (Raphanus sativus) que, por possuir alto teor protéico, se apresenta como possível sucedâneo do farelo de soja nas rações. Entretanto, faltam informações de seu valor nutritivo e da ação dos fatores antinutricionais presentes. Este estudo foi realizado na Unesp - Universidade Estadual Paulista, da Faculdade de Medicina Veterinária e Zootecnia, Campus de Botucatu, para determinar os coeficientes de digestibilidade aparente (CDA) da matéria seca (MS), proteína bruta (PB), energia bruta (EB), aminoácidos (AA) e a disponibilidade do fósforo do farelo de nabo forrageiro, pela tilápia-do-Nilo. Empregouse uma ração purificada (referência) e uma ração composta de 60% da ração referência e 40% do farelo de nabo forrageiro. O farelo de nabo forrageiro apresentou 91,28% de MS; 42,07% de PB, 4256 kcal/kg de EB, 3,47% de EE, 7,37% de FB, 1,25% de cálcio e 1,0% de fósforo. Os CDA foram de 55,92% para MS, 82,10% para PB, 75,26% para EB e 85,23% do fósforo. Os CDA dos AA estiveram entre 81,12% para a glicina e 95,11% para o ácido glutâmico. Os resultados demonstram que o farelo de nabo forrageiro apresenta potencial para ser usado como fonte protéica alternativa para compor a ração da tilápia do Nilo. / Oil seeds have been studied to produce bio combustibles. In order to obtain oil, seed processing results in several byproducts, among them, the fodder radish meal (Raphanus sativus) which has high protein content. This byproduct is a potential substitute to soybean meal in feed manufacture. However, there is a lack of information regarding its nutritional value and the anti-nutritional content and effects. This study was conduced at the Veterinary Medicine and Animal Science College from Sao Paulo State University, Botucatu, to determine the apparent digestibility coefficient (ADC) of dry matter (DM), crude protein (CP), raw energy (RE), amino acids (A) and phosphorus availability. The fish were fed a purified feed (base diet) and a 60% base diet plus 40% of fodder radish meal feed. Radish meal presented 91.98% DM, 42% CP, 4256 kcal/kg RE, 3.47% Ether extract, 7.37% crude fiber, 1.25% calcium and 1.0% phosphorus. The ADC values were DM: 55.92%, CP: 82.10%, RE: 75.26% and phosphorus: 85.23%. The ADC value for AA was 81.12% for glycine and 95.11% for glutamic acid. The results presented a potential utility for radish meal as an alternative protein source for Nile tilapia feeds.
24

Biochar de lodo de esgoto : efeitos no solo e na planta no cultivo de rabanete

Sousa, Alex Antônio Torres Côrtes de 30 January 2015 (has links)
Dissertação (mestrado)—Universidade de Brasília, Faculdade de Agronomia e Medicina Veterinária, 2015. / Submitted by Albânia Cézar de Melo (albania@bce.unb.br) on 2015-04-01T14:30:05Z No. of bitstreams: 1 2015_AlexAntonioTorresCortesSousa.pdf: 816369 bytes, checksum: ddc80ee1a1e20bae1ef5afeaed82bed7 (MD5) / Approved for entry into archive by Ruthléa Nascimento(ruthleanascimento@bce.unb.br) on 2015-04-17T19:06:37Z (GMT) No. of bitstreams: 1 2015_AlexAntonioTorresCortesSousa.pdf: 816369 bytes, checksum: ddc80ee1a1e20bae1ef5afeaed82bed7 (MD5) / Made available in DSpace on 2015-04-17T19:06:37Z (GMT). No. of bitstreams: 1 2015_AlexAntonioTorresCortesSousa.pdf: 816369 bytes, checksum: ddc80ee1a1e20bae1ef5afeaed82bed7 (MD5) / O biochar tem sido apresentado como uma alternativa viável para o uso agrícola do lodo de esgoto (LE) de forma sustentável. No entanto, ainda há dúvidas sobre os efeitos nutricionais do biochar em culturas de ciclo curto. O objetivo deste estudo foi avaliar o efeito de diferentes doses de biochar de LE nos componentes de fertilidade do solo e no desenvolvimento agronômico do rabanete, Raphanus sativus L. (Brassicae). O biochar de LE foi produzido com temperatura de pirólise de 300°C, a uma taxa média de aumento de temperatura de 11°C min-1, com um tempo de residência de 30 minutos. Um experimento foi instalado em casa de vegetação, cujo delineamento experimental utilizado foi o inteiramente casualizado com seis tratamentos e quatro repetições. Os tratamentos foram constituídos pelas seguintes doses de biochar, em Mg ha-1: 0,0 (controle); 20; 40; 60; 80; e 100. Foram avaliadas propriedades químicas do solo, antes e após o cultivo do rabanete. O desenvolvimento agronômico da cultura foi avaliado por meio das variáveis: número de folhas, altura da planta, comprimento foliar, massa seca da parte aérea e leitura SPAD. Foram avaliadas, ainda, as concentrações de nutrientes na planta e estimativa da produtividade. As variáveis testadas responderam ao aumento da dose do produto com as melhores respostas obtidas entre as doses de 20 e 60 Mg ha-1, sendo observada uma leve redução a partir da dose 60 Mg ha-1. Quanto às propriedades químicas do solo houve, de maneira geral, um enriquecimento dos nutrientes no solo com a aplicação do biochar. Esse aumento dos teores de nutrientes, principalmente fósforo e nitrogênio, e dos indicadores de fertilidade do solo se refletiram em maior concentração de nutrientes foliares, com respostas no maior desenvolvimento da planta. / Biochar has been presented as a viable alternative to the agricultural use of sewage sludge in a sustainable way. However, there are still doubts about the nutritional effects of biochar on short cycle crops. The objective of this study was to evaluate the effect of different doses of sewage sludge biochar on soil fertility components and agronomic development of the radish, Raphanus sativus L. (Brassicae). The sewage sludge was produced with biochar 300°C pyrolysis temperature at an average rate of temperature rise of 11°C min-1 with 30 minutes of residence time. One experiment was conducted in a greenhouse, whose experimental design was completely randomized with six treatments and four replications. The treatments consisted of the following doses of biochar in Mgha-1: 0.0 (control), 20, 40, 60, 80 and 100. Soil properties were evaluated before and after cultivation of radishes. The agronomic crop development was evaluated using the variables: number of leaves, plant height, leaf length, dry weight of shoot and index SPAD. Also the concentrations of nutrients in plant was evaluated and yield was estimated. The variables tested responded to the increase in dose of biochar 20 and 60 Mg ha-1, a slight decrease was observed from 60 Mg ha-1. On the chemical properties of the soil was, in general, an enrichment of nutrients in the soil with biochar application. This increase in nutrient levels, particularly phosphorus and nitrogen, and soil fertility indicators were suggested by a greater concentration of foliar nutrients, resulting in the further development of the plant.
25

ESTUDO DA DEGRADAÇÃO TÉRMICA DO ÓLEO E BIODIESEL DE GERGELIM PRETO (Sesamum indicum L.) E NABO FORRAGEIRO (Raphanus sativus L.) POR TÉCNICAS ESPECTROSCÓPICAS / DETERIORATION OF THE STUDY OF THERMAL OIL AND BIODIESEL SESAME BLACK (Sesamum indicum L.) AND TURNIP (Raphanus sativus L.) FOR TECHNICAL SPECTROSCOPIC

Vasconcelo, Maydla dos Santos 30 March 2015 (has links)
Submitted by Cibele Nogueira (cibelenogueira@ufgd.edu.br) on 2016-04-19T20:05:02Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) MAYDLAVASCONCELO.pdf: 2122334 bytes, checksum: 2d58735912a5e8994c591c91a411c4a4 (MD5) / Made available in DSpace on 2016-04-19T20:05:02Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) MAYDLAVASCONCELO.pdf: 2122334 bytes, checksum: 2d58735912a5e8994c591c91a411c4a4 (MD5) Previous issue date: 2015-03-30 / This study aimed to analyze the thermal degradation of oils and biodiesels (methyl esters of fatty acids) black sesame (Sesamum indicum L.) and forage turnip (Raphanus sativus L.). The degradation of oils and biodiesels was monitored by spectroscopic techniques and acid value. Samples were degraded in an oven at 110 ° C for 48 hours. The values for the acid number of the samples without degrading (0 h) was approximately 0.81 mgKOH /g and 0.06 mgKO /g respectively for the black sesame oil and biodiesel, since the values obtained for forage turnip oil and biodiesel were 0.35 mg KOH / g and 0.05 mg KOH / g, respectively. The results of acid value showed that both oils analyzed had higher acidity values than their respective biodiesels. The analysis by absorption spectroscopy in the visible ultraviolet possible to monitor the thermal degradation of oils and biodiesels in the region of 232 nm and 270 nm, related to the oxidation products so formed. The light absorption of the analyzed substance increased with time degradation of the samples in these two wavelengths. The fluorescence technique possible to observe that the oils and degraded in biodiesels unchanged light emission in the regions: the possible degradation products formed (424 nm) of α-tocopherol (322 nm) Chlorophyll (630 nm) in the region characteristic of conjugated tetraene derivatives degradation of the methyl esters (488 nm). Thus, through molecular spectroscopy, it is possible to monitor changes in physical and chemical characteristics of oils and biodiesels. To characterize the oils and biodiesels was used mid-infrared spectroscopy, however, this technique was not effective in monitoring the thermal degradation. / Este estudo teve como objetivo analisar a degradação térmica dos óleos e biodieseis (ésteres metílicos de ácidos graxos) de gergelim preto (Sesamum indicum L.) e de nabo forrageiro (Raphanus sativus L.). A degradação dos óleos e dos biodieseis foi monitorada por técnicas espectroscópicas e índice de acidez. As amostras foram degradadas em estufa à 110º C durante 48 horas. Os valores obtidos para o índice de acidez das amostras sem degradar (0 h) foram de aproximadamente 0,81 mgKOH/g e 0,06 mgKOH/g, respectivamente, para o óleo e biodiesel de gergelim preto, já os valores obtidos para o óleo e biodiesel de nabo forrageiro foram de 0,35 mgKOH/g e 0,05 mgKOH/g, respectivamente. Os resultados do índice de acidez mostraram que os dois óleos analisados apresentaram valores maiores de acidez que seus respectivos biodieseis. As análises por espectroscopia de absorção no ultravioleta visível permitiram monitorar a degradação térmica dos óleos e dos biodieseis na região de 232 nm e de 270 nm, referentes aos produtos de oxidação então formados. A absorção de luz das substâncias analisadas aumentou com o tempo de degradação das amostras nesses dois comprimentos de ondas. A técnica de fluorescência possibilitou observar que os óleos e os biodieseis degradados sofrem alterações na emissão de luz, nas regiões: dos possíveis produtos de degradação formados (424 nm), do α-tocoferol (322 nm), da clorofila (630 nm) e na região característica de tetraenos conjugados derivados da degradação dos ésteres metílicos (488 nm). Dessa forma, através da espectroscopia molecular, é possível monitorar alterações nas características físicas e químicas dos óleos e dos biodieseis. Para caracterizar os óleos e biodieseis foi utilizada a espectroscopia de infravermelho médio, entretanto, esta técnica não foi eficiente no monitoramento da degradação térmica.
26

Studies on the development of a novel seed production technology for cabbages using the grafting-induced flowering with radish rootstocks / ダイコン台木への接ぎ木による花成誘導を利用したキャベツの新規採種技術の開発に関する研究

Motoki, Ko 25 July 2022 (has links)
京都大学 / 新制・論文博士 / 博士(農学) / 乙第13498号 / 論農博第2902号 / 新制||農||1093(附属図書館) / 学位論文||R4||N5404(農学部図書室) / 京都大学大学院農学研究科農学専攻 / (主査)教授 中﨑 鉄也, 教授 土井 元章, 教授 田尾 龍太郎 / 学位規則第4条第2項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
27

Efeito residual do lodo de esgoto na produtividade e na ciclagem de nutrientes em plantios de Eucalyptus grandis e no cultivo de plantas alimentícias (simulando alteração do uso agrícola do solo) / Long term effect of the sewage sludge on productivity and nutrient cycling in Eucalyptus grandis stands and in food plants cultivation (simulating change in the agricultural use of the soil)

Ferraz, Alexandre de Vicente 22 January 2014 (has links)
Nas ultimas décadas, a elevação do consumo e do custo dos fertilizantes minerais tem preocupado o setor agrícola mundial. Portanto, o uso do lodo de esgoto tratado (biossólido) como adubo está sendo incentivado em diversos países, visto que aumenta a produtividade e gera benefícios pela reciclagem da matéria orgânica e nutrientes contidos em sua composição. Ainda assim, a presença de elementos potencialmente tóxicos (ex. metais pesados) no lodo e a falta de conhecimento sobre o seu efeito residual no ambiente, principalmente, em casos onde há a alteração do uso agrícola do solo, têm contribuído para a sua disposição final em aterros sanitários. Esta pesquisa pressupõe que o uso agrícola do lodo de esgoto, mesmo algum tempo após a sua aplicação ao solo, continua exercendo efeito residual favorável sobre a produtividade (biomassa) e a ciclagem de nutrientes em plantios de eucalipto, bem como em culturas de plantas alimentícias. No município de Itatinga-SP, foram instalados três experimentos com povoamentos de Eucalyptus grandis, sendo: (1) Prática de desbaste em dois talhões de eucalipto plantados em 1998, sobre Latossolo Vermelho-Amarelo (LVA) e Latossolo Vermelho Escuro (LVE), e adubados com 20 t ha-1 lodo de esgoto; (2) Prática da talhadia (condução de rebrota) em parcelas cultivadas com eucalipto e adubadas (em 2003) com 10, 20 e 30 t ha-1 de lodo de esgoto, aplicadas na forma úmida (torta) e seca (granulado) e (3) Prática de reforma em parcelas de eucalipto adubadas (em 2005) com 15 t ha-1 dos lodos produzidos pelas estações de tratamento de esgoto de Barueri, São Miguel e Parque Novo Mundo. Um quarto experimento procurou simular a alteração do uso agrícola do solo, pela substituição de povoamentos de eucaliptos adubados com lodo de esgoto (há catorze anos) por áreas de cultivo das espécies: Lactuca sativa L. (alface), Raphanus sativus L. e Oryza sativa L. (arroz de sequeiro). Neste experimento, as plantas foram cultivadas em vasos preenchidos com dois tipos de latossolo (LVA e LVE), ambos coletados em talhões de E. grandis adubados há catorze anos com lodo de esgoto. De modo geral, a adubação dos plantios de eucalipto com os lodos de esgoto elevou o teor de fósforo, cálcio e zinco no solo. Nas áreas de desbaste, as concentrações foliares de nutrientes foram mais elevadas nas árvores cultivadas sob efeito residual do lodo de esgoto; todavia, este efeito não foi suficiente para alterar o crescimento do tronco (em circunferência) das árvores. Na área de talhadia, a adubação com 10 t ha-1 de lodo de esgoto aplicado seco exerceu efeito residual positivo sobre a produção de biomassa aérea. Na área de reforma, a biomassa acumulada pelas árvores cultivadas sob efeito residual do lodo foi superior (até 150%) em relação à testemunha; além disso, este efeito residual do lodo trouxe reflexos positivos também na ciclagem de nutrientes, devido à maior deposição de folhedo. Sob o efeito residual do lodo de esgoto, as plantas alimentícias acumularam 2 a 5 vezes mais biomassa em relação ás respectivas testemunhas, principalmente ao serem cultivadas no LVA. Essas plantas apresentaram, também, concentrações mais elevadas de cádmio nas folhas, bem como de cromo e níquel nas raízes; todavia, em nenhum dos cultivos, foram excedidos os limites de metais pesados preconizados pela Agência de Vigilância Sanitária (ANVISA) do Brasil. / Over the last few decades, the increase in consumption and in the cost of mineral fertilizers has concerned overall agriculture. Therefore, the use of treated sewage sludge (biosolids) as fertilizer has being encouraged in many countries, inasmuch as it increases productivity and generates benefits by the recycling of organic matter and nutrients in its composition. Nevertheless, the presence of potentially toxic elements (e.g. heavy metals) in the sludge and the lack of knowledge about its long term effect on the environment, especially in cases where there is a change in agricultural use, have contributed to its final disposal in landfills. This research assumes that the agricultural use of sewage sludge, even some time after its application to the soil, have a favorable long term effect on productivity (biomass) and nutrient cycling in eucalypt stands, as well as in cultures of food plants. For this study, three experiments with Eucalyptus grandis were installed in Itatinga/SP: (1) Thinning practice in two eucalyptus stands planted in 1998, on sandy and clayey ferralsol (LVA and LVE, by its acronym in Portuguese), both fertilized with 20 t ha-1 of sewage sludge; (2) Coppicing practice (sprouting conduct) in eucalyptus plots fertilized (in 2003) with 10, 20 and 30 t ha-1 of wet and dry sewage sludge; and (3) Reform techniques in eucalyptus plots fertilized (in 2005) with 15 t ha-1 of sludge produced by Barueri\'s, São Miguel\'s and Parque Novo Mundo\'s wastewater treatment plants. A fourth experiment simulated the change of use of agricultural soil, by replacing eucalyptus stands fertilized with sewage sludge (fourteen years ago) for vegetable species: Lactuca sativa L. (lettuce), Raphanus sativus L. (radish) and Oryza sativa L. (upland rice). In this experiment, plants were grown in pots filled with two types of ferralsol (LVA and LVE), both collected in E. grandis stands fertilized with sewage sludge (14 years ago). In general, the eucalyptus stands fertilization with sewage sludge increased the phosphorus, calcium and zinc content in the soil. In thinning stands, the leaf nutrient concentrations were greater in trees grown under long term effect of sewage sludge; however, this effect was not sufficient to alter the growth of the trunk (in circumference). In coppice stands, the fertilization with 10 t ha-1 of dry sewage sludge had positive long term effect on the biomass production. In areas undergoing stand reform, the biomass accumulated by trees grown on long term effect of the sewage sludge was greater (150%) than the control. Furthermore, this effect of the sludge also brought positive impacts on nutrient cycling, due to an increasing in the leaf fall production. Under the long term effect of sewage sludge, the food plants accumulated 2 to 5 times more biomass than respective control treatments, especially if they are grown on the LVA. These plants also showed greater cadmium concentrations in the leaves, as well as greater chromium and nickel concentration in the roots. However, the concentrations of heavy metals didn\'t exceed the limits recommended by the Brazilian Health Surveillance Agency (ANVISA, by its acronym in Portuguese) in any of the crops.
28

Efeito residual do lodo de esgoto na produtividade e na ciclagem de nutrientes em plantios de Eucalyptus grandis e no cultivo de plantas alimentícias (simulando alteração do uso agrícola do solo) / Long term effect of the sewage sludge on productivity and nutrient cycling in Eucalyptus grandis stands and in food plants cultivation (simulating change in the agricultural use of the soil)

Alexandre de Vicente Ferraz 22 January 2014 (has links)
Nas ultimas décadas, a elevação do consumo e do custo dos fertilizantes minerais tem preocupado o setor agrícola mundial. Portanto, o uso do lodo de esgoto tratado (biossólido) como adubo está sendo incentivado em diversos países, visto que aumenta a produtividade e gera benefícios pela reciclagem da matéria orgânica e nutrientes contidos em sua composição. Ainda assim, a presença de elementos potencialmente tóxicos (ex. metais pesados) no lodo e a falta de conhecimento sobre o seu efeito residual no ambiente, principalmente, em casos onde há a alteração do uso agrícola do solo, têm contribuído para a sua disposição final em aterros sanitários. Esta pesquisa pressupõe que o uso agrícola do lodo de esgoto, mesmo algum tempo após a sua aplicação ao solo, continua exercendo efeito residual favorável sobre a produtividade (biomassa) e a ciclagem de nutrientes em plantios de eucalipto, bem como em culturas de plantas alimentícias. No município de Itatinga-SP, foram instalados três experimentos com povoamentos de Eucalyptus grandis, sendo: (1) Prática de desbaste em dois talhões de eucalipto plantados em 1998, sobre Latossolo Vermelho-Amarelo (LVA) e Latossolo Vermelho Escuro (LVE), e adubados com 20 t ha-1 lodo de esgoto; (2) Prática da talhadia (condução de rebrota) em parcelas cultivadas com eucalipto e adubadas (em 2003) com 10, 20 e 30 t ha-1 de lodo de esgoto, aplicadas na forma úmida (torta) e seca (granulado) e (3) Prática de reforma em parcelas de eucalipto adubadas (em 2005) com 15 t ha-1 dos lodos produzidos pelas estações de tratamento de esgoto de Barueri, São Miguel e Parque Novo Mundo. Um quarto experimento procurou simular a alteração do uso agrícola do solo, pela substituição de povoamentos de eucaliptos adubados com lodo de esgoto (há catorze anos) por áreas de cultivo das espécies: Lactuca sativa L. (alface), Raphanus sativus L. e Oryza sativa L. (arroz de sequeiro). Neste experimento, as plantas foram cultivadas em vasos preenchidos com dois tipos de latossolo (LVA e LVE), ambos coletados em talhões de E. grandis adubados há catorze anos com lodo de esgoto. De modo geral, a adubação dos plantios de eucalipto com os lodos de esgoto elevou o teor de fósforo, cálcio e zinco no solo. Nas áreas de desbaste, as concentrações foliares de nutrientes foram mais elevadas nas árvores cultivadas sob efeito residual do lodo de esgoto; todavia, este efeito não foi suficiente para alterar o crescimento do tronco (em circunferência) das árvores. Na área de talhadia, a adubação com 10 t ha-1 de lodo de esgoto aplicado seco exerceu efeito residual positivo sobre a produção de biomassa aérea. Na área de reforma, a biomassa acumulada pelas árvores cultivadas sob efeito residual do lodo foi superior (até 150%) em relação à testemunha; além disso, este efeito residual do lodo trouxe reflexos positivos também na ciclagem de nutrientes, devido à maior deposição de folhedo. Sob o efeito residual do lodo de esgoto, as plantas alimentícias acumularam 2 a 5 vezes mais biomassa em relação ás respectivas testemunhas, principalmente ao serem cultivadas no LVA. Essas plantas apresentaram, também, concentrações mais elevadas de cádmio nas folhas, bem como de cromo e níquel nas raízes; todavia, em nenhum dos cultivos, foram excedidos os limites de metais pesados preconizados pela Agência de Vigilância Sanitária (ANVISA) do Brasil. / Over the last few decades, the increase in consumption and in the cost of mineral fertilizers has concerned overall agriculture. Therefore, the use of treated sewage sludge (biosolids) as fertilizer has being encouraged in many countries, inasmuch as it increases productivity and generates benefits by the recycling of organic matter and nutrients in its composition. Nevertheless, the presence of potentially toxic elements (e.g. heavy metals) in the sludge and the lack of knowledge about its long term effect on the environment, especially in cases where there is a change in agricultural use, have contributed to its final disposal in landfills. This research assumes that the agricultural use of sewage sludge, even some time after its application to the soil, have a favorable long term effect on productivity (biomass) and nutrient cycling in eucalypt stands, as well as in cultures of food plants. For this study, three experiments with Eucalyptus grandis were installed in Itatinga/SP: (1) Thinning practice in two eucalyptus stands planted in 1998, on sandy and clayey ferralsol (LVA and LVE, by its acronym in Portuguese), both fertilized with 20 t ha-1 of sewage sludge; (2) Coppicing practice (sprouting conduct) in eucalyptus plots fertilized (in 2003) with 10, 20 and 30 t ha-1 of wet and dry sewage sludge; and (3) Reform techniques in eucalyptus plots fertilized (in 2005) with 15 t ha-1 of sludge produced by Barueri\'s, São Miguel\'s and Parque Novo Mundo\'s wastewater treatment plants. A fourth experiment simulated the change of use of agricultural soil, by replacing eucalyptus stands fertilized with sewage sludge (fourteen years ago) for vegetable species: Lactuca sativa L. (lettuce), Raphanus sativus L. (radish) and Oryza sativa L. (upland rice). In this experiment, plants were grown in pots filled with two types of ferralsol (LVA and LVE), both collected in E. grandis stands fertilized with sewage sludge (14 years ago). In general, the eucalyptus stands fertilization with sewage sludge increased the phosphorus, calcium and zinc content in the soil. In thinning stands, the leaf nutrient concentrations were greater in trees grown under long term effect of sewage sludge; however, this effect was not sufficient to alter the growth of the trunk (in circumference). In coppice stands, the fertilization with 10 t ha-1 of dry sewage sludge had positive long term effect on the biomass production. In areas undergoing stand reform, the biomass accumulated by trees grown on long term effect of the sewage sludge was greater (150%) than the control. Furthermore, this effect of the sludge also brought positive impacts on nutrient cycling, due to an increasing in the leaf fall production. Under the long term effect of sewage sludge, the food plants accumulated 2 to 5 times more biomass than respective control treatments, especially if they are grown on the LVA. These plants also showed greater cadmium concentrations in the leaves, as well as greater chromium and nickel concentration in the roots. However, the concentrations of heavy metals didn\'t exceed the limits recommended by the Brazilian Health Surveillance Agency (ANVISA, by its acronym in Portuguese) in any of the crops.
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Ecology and evolution of tolerance in two cruciferous species

Boalt, Elin January 2008 (has links)
<p>Tolerance to herbivory is the ability of plants to maintain fitness in spite of damage. The goal of this thesis is to investigate the genetic variation and expression of tolerance within species, determine whether and in what conditions tolerance has negative side-effects, and how tolerance is affected by different ecological factors. Tolerance is investigated with special focus on the effects of different damage types, competitive regimes, history of herbivory, and polyploidization in plants. Studies are conducted as a literature review and three experiments on two cruciferous species Raphanus raphanistrum and Cardamine pratensis.</p><p>In the tolerance experiments, plants are subjected to artificial damage solely, or in a combination with natural damage. A literature review was conducted in order to investigate the effects of damage method. We found that traits related to tolerance, such as growth and fitness were not as sensitive in regard to damage method as measures of induced chemical traits, or measures of secondary herbivory.</p><p>Genetic variation of tolerance was demonstrated within populations of R. raphanistrum and between subspecies of C. pratensis. In R. raphanistrum, traits involved in floral display and male fitness were positively associated with plant tolerance to herbivore damage. A potential cost of tolerance was demonstrated as a negative correlation between levels of tolerance in high and low competitive regimes. I found no evidence of other proposed costs of tolerance in terms of highly tolerant plants suffering of reduced fitness in the absence of herbivores or trade-offs in terms of a negative association between tolerance to apical and leaf damage, or between tolerance and competitive ability. In C. pratensis, higher ploidy level in plants involved higher levels of tolerance measured as clonal reproduction. Furthermore, populations exposed to higher levels of herbivory had better tolerance than populations exposed to lower levels of herbivory. In this thesis, I demonstrate evidence of different components for the evolution of tolerance in plants: genotypic variation, selective factors in terms of costs and ploidization, and selective agents in terms of changing environment or herbivore pressure.</p>
30

Ecology and evolution of tolerance in two cruciferous species

Boalt, Elin January 2008 (has links)
Tolerance to herbivory is the ability of plants to maintain fitness in spite of damage. The goal of this thesis is to investigate the genetic variation and expression of tolerance within species, determine whether and in what conditions tolerance has negative side-effects, and how tolerance is affected by different ecological factors. Tolerance is investigated with special focus on the effects of different damage types, competitive regimes, history of herbivory, and polyploidization in plants. Studies are conducted as a literature review and three experiments on two cruciferous species Raphanus raphanistrum and Cardamine pratensis. In the tolerance experiments, plants are subjected to artificial damage solely, or in a combination with natural damage. A literature review was conducted in order to investigate the effects of damage method. We found that traits related to tolerance, such as growth and fitness were not as sensitive in regard to damage method as measures of induced chemical traits, or measures of secondary herbivory. Genetic variation of tolerance was demonstrated within populations of R. raphanistrum and between subspecies of C. pratensis. In R. raphanistrum, traits involved in floral display and male fitness were positively associated with plant tolerance to herbivore damage. A potential cost of tolerance was demonstrated as a negative correlation between levels of tolerance in high and low competitive regimes. I found no evidence of other proposed costs of tolerance in terms of highly tolerant plants suffering of reduced fitness in the absence of herbivores or trade-offs in terms of a negative association between tolerance to apical and leaf damage, or between tolerance and competitive ability. In C. pratensis, higher ploidy level in plants involved higher levels of tolerance measured as clonal reproduction. Furthermore, populations exposed to higher levels of herbivory had better tolerance than populations exposed to lower levels of herbivory. In this thesis, I demonstrate evidence of different components for the evolution of tolerance in plants: genotypic variation, selective factors in terms of costs and ploidization, and selective agents in terms of changing environment or herbivore pressure.

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