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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.
31

Turfa: interações com espécies metálicas e estudo de parâmetros que influenciam na utilização em setores agrícolas

Mendonça, André Gustavo Ribeiro [UNESP] 29 January 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-01-29Bitstream added on 2014-06-13T20:45:58Z : No. of bitstreams: 1 mendonca_agr_dr_araiq.pdf: 5684091 bytes, checksum: 9b3a80cd7c8f6c2fa5faeeb3ca0ed1b9 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Turfas apresentam em média 80% de compostos orgânicos em sua composição. A variedade e elevada quantidade de grupos funcionais, principalmente oxigenados, nitrogenados e sulfurados, possibilitam elevada capacidade de interação com espécies metálicas, formando compostos de diferentes estabilidades. Além da importante função ambiental, tais como participação em processos de acúmulo, transporte e disponibilidade de espécies metálicas no ambiente, as turfas possuem várias aplicações comerciais, dentre elas, destaca-se a remediação de áreas contaminadas e utilização na agricultura e horticultura, onde são empregadas como adubo natural. Quanto à aplicação de turfas no setor agrícola, há uma crescente procura pela adubação orgânica. Neste caso, existem várias questões em aberto como, por exemplo, a necessidade de entendimento da disponibilização ou não de nutrientes pela matéria orgânica, quando enriquecida com macro e micro nutrientes essenciais. Neste trabalho, foram estudadas as interações de espécies metálicas (Cu, Mg, Ca, Zn, Mn e Fe) com turfas e substâncias húmicas extraídas dessas matrizes. Foram coletadas amostras de turfas no Distrito de Taquaral-SP e no município de São Simão-SP. As amostras foram caracterizadas com diferentes técnicas, tais como: granulometria, infra-vermelho, análise elementar, RMN 13 C CP- MAS / RMN DOSY e HPSEC. Foram determinadas as capacidades de complexação e constantes de troca entre as substâncias húmicas extraídas das amostras de turfas e espécies metálicas. Experimentos em casa de vegetação (UNESP – Jaboticabal) foram feitos para avaliar a influência das diferentes amostras e das quantidades de turfas no desenvolvimento e estado nutricional das plantas testadas (milho e rabanete). Os resultados deste trabalho contribuem no melhor entendimento sobre alguns fatores que influenciam... / Peats of natural origin have on average 80% of organic compounds in its composition. The variety and high quantity of functional groups, mainly oxygen, nitrogen and sulfur, enable high capacity for interaction with metal species, forming compounds of different stability. Beyond the environmental importance, such as participation in processes of accumulation, transportation and disposal of metal species in the environment, peats have various commercial applications, among which stands out the remediation of contaminated areas and the use in agriculture and horticulture, where they are used as natural fertilizer. As for the application of peats in the agricultural sector, there is a growing demand for organic fertilizer. In this case, there are several open issues such as the need for understanding the availability or not of nutrients in organic matter, when enriched with macro and micro essential nutrients. In this work, were have studied the interactions of metal species (Cu, Mg, Ca, Zn, Mn and Fe) with peats and humic substances. Peat samples were collected in the Taquaral-SP district and the São Simão-SP city. The samples were characterized with different techniques, such as size, infrared spectroscopy, elemental analysis, 13 C NMR CP-MAS / NMR DOSY and HPSEC. The capacity of complexation and exchange constants between humic substances extracted from peat samples and metal species were determined. Experiments in a greenhouse (UNESP - Jaboticabal) were carried out to evaluate the influence of the different samples and the quantities of peat in the development and status of tested plants (corn and radish). The results of this study contribute for a better understanding of factors that influence the interactions between metal species and soil organic matter, for improvements in agricultural practices, aiming at better yields and less environmental impacts
32

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

Santos, Vivian Gomes dos, 1981- January 2008 (has links)
Resumo: 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. / Abstract: 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. / Orientador: Luiz Edivaldo Pezzato / Coorientador: Margarida Maria Barros / Banca: Wilson Maddamitu Furuya / Banca: José Roberto Sartori / Mestre
33

Effects of Libyan traditional plants on the reproductive system of male and female rats

Elgenaidi, Abdalla Ramadan January 2015 (has links)
Philosophiae Doctor - PhD / In different parts of the world, medicinal plants have demonstrated a lot of health benefits to mankind and remains an important source for the discovery of new bio-active compounds. Libya is a typical example of a country where medicinal plants are widely used. Plant extracts of five Libyan medicinal plants were used in this study to investigate their in vivo effects on spermatogenesis and steroidogenesis in male rats and on ovulation and fertility in female rats. The In vitro effects of these plant extracts were also investigated on TM3 Leydig cells and MCF 7 breast cancer cells. A phyto-chemical analysis of the five Libyan medicinal plants (flaxseed, black seeds, radish seed, date palm pollen and nutmeg) was done. The results showed that date palm pollen had a higher antioxidant activity than all of the above mentioned plants. In addition to this, Nigella sativa was observed to possess high flavonol content as well as high antioxidant activity. Male rats exposed to flaxseed, radish seeds and date palm pollen showed no significant alterations in body weight gain, whereas date palm pollen (240 mg/kg, p < 0.05) promoted an increase in body gain. This study also revealed a significant increase in the relative testicular weight of animals exposed to either flaxseed (300mg/kg) or date palm pollen (120mg/kg). In addition, the relative weights of the seminal vesicles of all treated groups showed significant increased values. The level of serum testosterone showed a significant increase after exposure to radish seed (80mg/kg) and a significant dose- dependent increase for date palm pollen when compared to control (P< 0.05). In contrast, flaxseed caused a dose-dependent significant (p <0.01) decrease in testosterone level at radish seed (300mg/Kg). All plant extracts caused a significant increase in sperm concentration. Sperm vitality significantly (p < 0.05) increased by radish seed (80mg/kg), flaxseed (300mg/kg) and date palm pollen (120, 240mg/kg) respectively. Total progressive motility improved significantly at flaxseed (300 mg/kg) (p < 0.001) as well as date palm pollen (p < 0.01). Histological examination of the cross sections of the testis showed clear presence of all stages of spermatogenesis in all the treated groups. Rat epididymides showed normal morphological appearance and their lumen were filled with spermatozoa. The diameter of seminiferous tubules in male rats exposed to date palm pollen (120 and 240 mg/kg) was significantly higher (p < 0.001). The heights of the germ cell epithelia within the eminiferous tubules were also significantly increased in all treated groups. Liver and renal functions tests showed a significant decrease in Alanine transaminase (ALT) and creatinine in all treated groups (p < 0.05), and this demonstrates the lack of cytotoxic effects of date palm pollen, radish seed and flaxseed on the rats. However, these plant extracts produced a non-significant (p > 0.05) increase in Aspartate transaminase (AST) levels. Besides this, superoxide dismutase activity (SOD) in testis was increased significantly by radish seed (160 mg/kg), flaxseed (200 mg/kg) and date palm pollen (120 mg/kg). There was also improved catalase activity in testis of male rats exposed to radish seed and date palm pollen. Regarding male sexual behavior, the time to reach the female and the mount frequency decreased significantly in male rats exposed to flaxseed (300 mg/kg) and date palm pollen (120 and 240 mg/kg; p > 0.05) thus, these plant extracts exhibit aphrodisiac properties. In addition, exposure of male rats to date palm pollen (120 mg/kg) produced a significant (p < 0.01) increase in the number of embryos in untreated female rats. In the female rats, the body weight gain was not affected (p > 0.05). However, the relative uterus weights exposed to nutmeg (200 mg/kg) and date palm pollen (120 and 240 mg/kg) were significantly decreased (p < 0.05). In addition, the relative weights of ovaries after treatment with nutmeg (400 mg/kg) and black seed (400 mg/kg) showed significantly increased values (p < 0.01). Serum FSH was significantly increased (p > 0.05 or 0.01) when the female rats have been exposed to black seed (200 mg/kg), nutmeg (200 mg/kg) or date palm pollen (120 mg/kg). The LH level significantly (p < 0.01) decreased following exposure to black seed (200 mg/kg), date palm pollen (120 mg/kg). On the other hand, serum LH concentration was significantly increased in female rats exposed nutmeg (400 mg/kg; p > 0.05). The creatinine activity in female rat serum in all treated groups was significantly decreased (p < 0.05). Whereas the higher dose of date palm pollen (240 mg/kg) caused only a non-significant decrease. ALT activity in serum of female rat exposed to either black seed (400 mg/kg) or date palm pollen (120 and 240 mg/kg) was shown to decrease significantly (p < 0.05). Histology of the reproductive organs, kidney and liver in the female rats showed no obvious alterations in any of the treated groups. In addition, the number of embryos in female rats significantly increased (p < 0.01; p < 0.001) following exposure of female rats to black seeds 400 and date palm pollen 240 mg/kg, respectively. Incubation of TM3 Leydig cells with radish seeds for 24, 48 or 72 hours caused a significant (p < 0.01) decrease in mitochondrial dehydrogenase activity. Besides that, date palm pollen and flaxseed increased the mitochondrial dehydrogenases activity of TM3 Leydig cells. In addition, higher concentration of date palm pollen, nutmeg and black seed were cytotoxic to MCF7 breast cells. In testis slices testosterone secretion in vitro was significantly increased by flaxseed (500 μg/ml; p > 0·05) and date palm pollen (500 μg/ml; p > 0·01). MCf-7 cells treated with BS 10-50 μg/ml black seed and nutmeg 10-50μg/ml significantly increased cell proliferation. However, the treatment with date palm pollen produced only a weak estrogenic effect, which resulted in a concentration dependent significant increase as observed between 50-1000 μg/ml date palm pollen. In conclusion, in this study, we observed that date palm pollen, radish seed and flaxseed increased libido as well as steroidogenesis and spermatogenesis, improved hepato and nephron-protective effects. In female rats, the plant extracts NM, BS and date palm pollen potentiated the production of gonadotropic hormones. In addition to this, at lower concentrations these medicinal plants promoted cell growth, whereas at higher concentrations they inhibited cell proliferation of MCF- 7 breast cancer cells. The anti-oxidant effects of these plant extracts have been implicated for the above mention effects.
34

Pollination processes - maternal and offspring performance

Holmén Bränn, Kristina January 2007 (has links)
<p>Pollination is one of the most important factors determining the reproductive success of plants. This thesis examines processes associated to varying pollination, with focus on plant responses. The first aim was to examine the possibility and constraints for short-term evolution of flower size in <i>Raphanus raphanistrum</i>. The results showed that there exists a possibility for pollinator-mediated short-term evolution of flower size in the study species. Flower size was strongly correlated to plant size. Since flower size cannot evolve separately from plant size, this correlation may constitute a constraint to the evolution of flower size. The second aim was to determine how varying pollen load affects later flowering, reproduction and growth of maternal plants. High pollen load treatment resulted in larger or more flowers on late flowers, which may enhance pollen dispersal and reproductive success, while the total seed mass was the same between treatments. The results indicate that the study species <i>R. raphanistrum</i>, <i>Sinapis arvensis</i> and <i>Brassica napus</i> have plastic responses in floral traits according to the present pollination level. The third aim was to determine how varying pollen load affects seed quality and offspring vigor. The results suggest that high pollen load had no positive effects on seed quality or offspring vigor due to pollen competition. Instead, seed mass determined seed quality and offspring vigor in the three study species and low pollen load treatment resulted in highquality offspring due to heavier seeds. The fourth aim was to examine causes and consequences of variation in reproductive success of <i>Succisa pratensis</i> on a regional scale. The results suggest that the most important variables, on a regional scale, for reproductive success were population size and habitat quality. The results showed that seed weight variation might be important when assessing reproductive success. In this study, seed weight variation did not seem to be adaptive.</p>
35

Pollination processes - maternal and offspring performance

Holmén Bränn, Kristina January 2007 (has links)
Pollination is one of the most important factors determining the reproductive success of plants. This thesis examines processes associated to varying pollination, with focus on plant responses. The first aim was to examine the possibility and constraints for short-term evolution of flower size in Raphanus raphanistrum. The results showed that there exists a possibility for pollinator-mediated short-term evolution of flower size in the study species. Flower size was strongly correlated to plant size. Since flower size cannot evolve separately from plant size, this correlation may constitute a constraint to the evolution of flower size. The second aim was to determine how varying pollen load affects later flowering, reproduction and growth of maternal plants. High pollen load treatment resulted in larger or more flowers on late flowers, which may enhance pollen dispersal and reproductive success, while the total seed mass was the same between treatments. The results indicate that the study species R. raphanistrum, Sinapis arvensis and Brassica napus have plastic responses in floral traits according to the present pollination level. The third aim was to determine how varying pollen load affects seed quality and offspring vigor. The results suggest that high pollen load had no positive effects on seed quality or offspring vigor due to pollen competition. Instead, seed mass determined seed quality and offspring vigor in the three study species and low pollen load treatment resulted in highquality offspring due to heavier seeds. The fourth aim was to examine causes and consequences of variation in reproductive success of Succisa pratensis on a regional scale. The results suggest that the most important variables, on a regional scale, for reproductive success were population size and habitat quality. The results showed that seed weight variation might be important when assessing reproductive success. In this study, seed weight variation did not seem to be adaptive.
36

Água de reúso em rabanete (Raphanus sativus L.): implicações agronômicas e sanitárias / Water reuse in radish (Raphanus sativus L.): sanitary and agronomics implications

Mendes, Paulo Eduardo Ferreira 06 February 2014 (has links)
Made available in DSpace on 2016-06-02T18:55:27Z (GMT). No. of bitstreams: 1 5919.pdf: 863312 bytes, checksum: 94d742c1d646f4987c489e8e1ccee135 (MD5) Previous issue date: 2014-02-06 / Financiadora de Estudos e Projetos / Due to increasingly irrigation water source scarcity, treated wastewater (TWW) is becoming a more attractive by nutrients source, showing sanitary and agronomics feasibility. In this way, this research evaluated, in a greenhouse conditions influence of superficial drip irrigation on radish (Raphanus sativus L.) cv. Crimson Giant production and nutritional status, as well as, soil chemical attributes changes; and, soil and radish sanitary contamination risk submitted to two water sources. The experiment was carried out at CCA/UFSCar, Araras, SP and a completely randomized design was adopted, with two treatments [AB- potable water (PW) and AR- treated wastewater (TWW)]. Soil and radish sample were submitted to sanitary analyses. The results showed that drip TWW didn t commit radish nutritional, production and increased macronutrients availability. However, soil sodium adsortion ratio (SAR) and exchangeable sodium percentage (ESP) increased by TWW application, but without salinization and sodification risk. Furthermore, radish showed out of sanitary conditions, indicated by the E. coli and total coliformis contamination, impossible its commercialization and in natura consumption. Considering the obtained results, suggest take appropriate action to improve the TWW treatment efficiency and promote radish sanitary conditions. The obtained results demonstrated the wastewater reuse feasibility as a source of nutrients to radish, substituting or reducing the application of commercial fertilizers and reducing the cost production. / Devido à crescente escassez de fontes hídricas para irrigação, a água de reúso tratada (AR) tem-se tornado cada vez mais interessante por sua composição em nutrientes, viabilidade agronômica e sanitária. Nesse sentido, esta pesquisa avaliou em ambiente protegido a influência da irrigação por gotejamento superficial no estado nutricional e produção do rabanete (Raphanus sativus L.) cv. Crimson Giant submetido a duas fontes de água, assim como as alterações nos atributos químicos do solo e o risco de contaminação sanitária de rabanete e do solo. O experimento foi conduzido no CCA/UFSCar, Araras/SP, adotando-se delineamento inteiramente casualizado, com dois tratamentos: água de abastecimento (AB) e água de reúso tratada (AR). Amostras de solo e rabanete foram submetidas a análises sanitárias. Os resultados permitiram concluir que a AR por gotejamento não comprometeu o estado nutricional, a produção do rabanete e elevou a disponibilidade de macronutrientes. Porém, a razão de adsorção de sódio (RAS) e a percentagem de sódio trocável (PST) do solo se elevaram, embora sem risco de salinização e sodificação. Além disso, o rabanete mostrouse fora dos padrões sanitários, indicados pela contaminação por coliformes totais e E. coli, impossibilitando a comercialização e consumo in natura. Considerando-se os resultados obtidos, sugere-se a adoção de medidas que visem à melhoria da eficiência do tratamento da AR e propicie a qualidade higiênico-sanitária do rabanete. Os resultados demonstraram a viabilidade do efluente, como fonte de nutrientes, substituindo ou diminuindo as adubações com fertilizante e reduzindo os custos de produção.
37

Variabilidade genética entre progênies de meios irmãos de nabo forrageiro (Raphanus sativus L. var. Oleiferus) cultivar Cati Al 1000

Sá, Rogério Oliveira de [UNESP] 11 February 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-02-11Bitstream added on 2014-06-13T19:39:59Z : No. of bitstreams: 1 sa_ro_me_botfca.pdf: 322008 bytes, checksum: ee9da95a6159f5e5fc33c0c3b613a125 (MD5) / Bayer S.A. / O presente trabalho de pesquisa teve como objetivo, avaliar a variabilidade genética de nabo forrageiro cultivar CATI AL 1000 por meio de progênies de meios irmãos, e obter estimativas de parâmetros genéticos para as características: ciclo das plantas, altura das plantas, produtividade de grãos, massa de 1000 grãos, e teor de óleo no grão, sendo conduzido na Fazenda Experimental da UNESP em São Manuel, campus de Botucatu - SP. Foram avaliadas 100 progênies de meios irmãos, distribuídas em Látice triplo 10x10, parcialmente balanceado. Para as características ciclo das plantas, produtividade de grãos, massa de 1000 grãos e teor de óleo no grão, foi detectado diferença significativa para o quadrado médio de progênies, pelo teste F. Para a característica ciclo das plantas, o valor médio e a amplitude de variação das progênies foram, 137 dias, 121 - 158 dias respectivamente. As estimativas dos coeficientes de herdabilidade e ganho de seleção apresentaram os seguintes valores, 45,90 % e 1,09 %. Para característica produtividade de grãos, a média e amplitude de variação de progênies foram, 7,40 g, 0,78 - 18,55 g, (49,40 kg/ha, 5,20 - 123,70 kg/ha) respectivamente. As estimativas dos coeficientes de herdabilidade e ganho de seleção esperado, foram superiores em relação aos encontrados na literatura, comparando-se com populações de milho, para característica produtividade de grão, com valores de 90,70 % e 19,30 % respectivamente. A massa de 1000 grãos apresentou valores para a média e amplitude de variação de progênies de, 7,95 g, 3,35 - 13,51 g, respectivamente. As estimativas dos coeficientes de herdabilidade e ganho de selção apresentaram os seguintes valores, 56,80 % e 4,80 %. Para a característica teor de óleo no grão, a média e amplitude de variação de progênies foram 34,42 %, 26,98 - 41,67 %, respectivamente... / The objective of the present study was to evaluate fodder radish genetic variability, cultivar CATI AL 100, by using half-sib progenies, and to obtain estimates of genetic parameters for the characteristics: plant cycle, plant height, grain yield, mass of 1000 seeds, and seed oil content, being carried out at UNESP Experimental Farm in São Manuel municipal districtal, Botucatu campus (São Paulo State, Brazil). A hundred half-sib progenies were distributed in triple latice scheme 10x10, partially balanced. For the characteristics plant cycle, grain yield, mass of 1000 seeds, and seed oil content, was detected, for the progenies medium square, significant difference, by F test. For the characteristic plant cycle, the average value and progenies range were 137 days and 121 - 158 days, respectively. The estimates of the inheritability coefficients and selection gain presented the following values: 45,90 % e 1,09 %. For grain yield character, the average value and progenies range were 7,40 g, 0,78 - 18,55 g (49,40 kg ha-1, 5,20 - 123,70 kg ha-1) respectively. The estimates of the inheritability coefficients and expected selection gain, were higher than those ones found in literature, being compared with maize populations, for grain yield, with values of 90,70 % and 19,30 % respectively. The mass of 1000 seeds presented values for the average and progenies range of 7,95 g, 3,35 - 13,51 g, respectively. The estimates of inheritability coefficients and selection gain showed the following values: 56,80 % e 4,80 % For the characteristic seed oil content, the average and progenies range were 34,42 %, 26,98 - 41,67 % respectively...(Complete abstract click electronic access below)
38

Competição de azevém e nabo, manejo de nitrogênio e dessecação pré-colheita na produção de sementes de trigo

Tavares, Lizandro Ciciliano 24 June 2015 (has links)
Submitted by Aline Batista (alinehb.ufpel@gmail.com) on 2016-08-03T13:35:20Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) tese_lizandro_tavares.pdf: 1225836 bytes, checksum: 987635fed6f9fe4f72fab3840a1a03b8 (MD5) / Made available in DSpace on 2016-08-03T13:35:20Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) tese_lizandro_tavares.pdf: 1225836 bytes, checksum: 987635fed6f9fe4f72fab3840a1a03b8 (MD5) Previous issue date: 2015-06-24 / A competição de azevém e nabo e a estimativa de dano econômico de nabo na cultura do trigo, além de práticas de manejo como a dessecação em pré-colheita com herbicidas e aplicação de trinexapac-ethyl e nitrogênio são fatores que merecem atenção pela pesquisa, visto que influenciam diretamente a produtividade e a qualidade fisiológica das sementes. O trabalho teve por objetivo avaliar a produtividade e a qualidade fisiológica de sementes de trigo produzidas em competição com azevém e/ou nabo (experimento 1); quantificar a produtividade, a qualidade fisiológica e o resíduo em sementes de trigo após a dessecação com herbicidas (experimento 2); avaliar a produtividade e a qualidade fisiológica de sementes de trigo em competição com nabo e sob a aplicação de trinexapac-ethyl e nitrogênio (experimento 3); e, estimar o nível de dano econômico de nabo em competição com as cultivares de trigo BRS 328, BRS 177 e BRS Umbu (experimento 4). Para as pesquisas realizadas o delineamento experimental adotado foi em blocos ao acaso, com quatro repetições, com exceção do ensaio 4 que utilizou uma repetição. O primeiro ensaio foi realizado com a cultivar BRS 177, o segundo com as cultivares BRS 177 e BRS Umbu, o terceiro com a cultivar BRS Guamirim e o quarto com as cultivares BRS 328, BRS 177 e BRS Umbu. As variáveis analisadas no experimento 1 foram número de antécios por espiga, número de sementes por espiga, peso hectolítrico, peso de mil sementes e produtividade. No experimento 2 avaliaram-se o peso de mil sementes, peso hectolítrico, número de antécios por espiga e a produtividade de sementes, além dos resíduos gerados nas sementes após a aplicação dos herbicidas em pré-colheita. No experimento 3 avaliaram-se o número de sementes por espiga e número de antécios, índice de colheita, produtividade biológica, produtividade de sementes, peso hectolítrico e peso de mil sementes e no experimento 4 avaliaram-se a população de plantas, massa seca da parte aérea, cobertura do solo, área foliar e produtividade. Ainda, nos três primeiros experimentos a qualidade fisiológica das sementes foram avaliadas por testes de vigor e germinação. Conclui-se que a competição de trigo na população de 5 plantas m-2 com azevém, nabo ou nabo + azevém reduz a produtividade da cultura, independentemente da época de emergência das plantas em relação as plantas daninhas, entretanto não prejudica a viabilidade e o vigor das sementes produzidas. A dessecação em pré-colheita com herbicida realizada em estádio posterior a maturidade fisiológica, de maneira geral, não influencia a qualidade fisiológica e a produtividade de sementes de trigo das cultivares BRS Umbu e BRS 177, entretanto apresentam resíduos nos grãos. A cultivar de trigo BRS Guamirim em competição com nabo submetido à adubação suplementar com nitrogênio, de maneira geral, apresenta aumento da produtividade de sementes até a dose de 100 kg ha-1, enquanto na ausência da competição o aumento ocorre até a dose de 150 kg ha-1, apesar da qualidade fisiológica das sementes serem reduzidas com o incremento das doses. A cultivar de trigo BRS 328, ciclo precoce, apresenta maior habilidade competitiva comparativamente a BRS 177, ciclo médio, e BRS Umbu, ciclo tardio. A planta daninha Raphanus raphanistrum mostra-se competitiva com a cultura trigo, sendo necessário no mínimo 1,6 plantas m-2 para que o controle se justifique. / The ryegrass and wild radish competition and the estimated wild radish economic threshold in wheat crop, besides management practices as herbicide pre-harvesting desiccation and application of trinexapac-ethyl and nitrogen are factors that deserve attention by the research, as they directly influence productivity and seed physiological quality. This study aimed to evaluate the productivity and physiological quality of wheat seeds produced in competition with ryegrass and/or wild radish (experiment 1); measure the yield, physiological quality and the residue in wheat seeds after herbicide desiccation (experiment 2); evaluate the productivity and physiological quality of wheat seeds in competition with wild radishes and under trinexapac-ethyl and nitrogen application (Experiment 3); and estimate the economic level of wild radish in competition with the wheat cultivars BRS 328, BRS 177 and BRS Umbu (experiment 4). To research performed the experimental design was a randomized block with four replications, except for the fourth experiment that used one replication. The first trial was conducted with BRS 177 cultivar, the second with the BRS 177 and BRS Umbu cultivars, the third with BRS Guamirim and the forth with the BRS 328, BRS 177 and BRS Umbu cultivars. The variables analyzed in experiment 1 were number of anthecium per spike, number of seeds per spike, test weight, thousand seed weight and productivity. In experiment 2 assessed the weight of a thousand seeds, test weight, number of anthecium per spike and seed yield, in addition to the residual generated in the seeds after herbicide application before the harvest. In Experiment 3 was evaluated the number of seeds per spike and number of anthecium, harvest index, biological yield, seed productivity, test weight and thousand seed weight and experiment 4 were evaluated plant population, dry mass of plant aerial part, soil cover, leaf area and productivity. Still, in the first three experiments the physiological seed quality was evaluated by germination and vigor tests. It was concluded that wheat competition in the population of 5 plants m-2 with ryegrass, wild radish or wild radish + ryegrass reduces crop yield, regardless of the time plant emergence over the weeds, however not affect the viability and vigor of produced seeds. The herbicide pre-hasvest desication held after physiological maturity stage, in general, does not affect the physiological quality of wheat seeds or it productivity in BRS Umbu and BRS 177 cultivars, however it shows residues present in grains. The wheat cultivar BRS Guamirim in competition with wild radish subjected nitrogen supplementar fertilization, in general, has increased seed yield until the dose of 100 kg ha-1, while in the absence of competition its increased until the dose of 150 kg ha-1, despite the physiological quality of seeds being reduced with increasing doses. The wheat cultivar BRS 328, early maturing, presents greater competitive ability compared to BRS 177, medium cycle, and BRS Umbu, late cycle. The weed Raphanus raphanistrum proves to be competitive with the wheat crop, requiring at least 1.6 plants m-2 so that the control is justified.
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Conséquences écologiques et évolutives du flux de gènes entre Brassica napus transgénique et ses apparentés sauvages

Liu, Yongbo 29 October 2010 (has links) (PDF)
Les conséquences des flux de gènes et de l'introgression entre les cultures transgéniques et leurs apparentés sauvages sont encore au cœur des débats associés à la commercialisation des plantes génétiquement modifiées. J'ai développé mon étude sur les conséquences écologiques et évolutives du flux de gènes entre le colza (Brassica napus) et ses apparentés, la moutarde brune sauvage (B. juncea) et la ravenelle (Raphanus raphanistrum), en réalisant une série d'expériences en serre, au jardin et au champ à Beijing et à Dijon. En premier, j'ai présenté une revue synthétique de la littérature publiée sur les flux de gènes et ses effets sur la fitness chez les Brassicées. En second, j'ai cherché à mettre en évidence le rôle de la taille des semences hybrides entre du colza transgénique Bt et la moutarde. La petite taille des semences a réduit les capacités de croissance et de reproduction, mais l'effet sur la fitness était variable en fonction des fonds génétiques ou spécifiques. Les rétrocroisements sur le colza étaient plus faciles et productifs que pour les autres types de descendants. La plupart de ces plantes avait une morphologie de colza. Liée à la résistance à l'herbicide, cette caractéristique pourrait permettre aux descendants de survivre dans les champs et de disséminer les transgènes aux repousses et aux autres colzas, ce qui serait peut être plus gênant que de voir l'introgression réelle dans le génome du parent sauvage. Troisièmement, j'ai simulé le phénomène d'herbivorie chez la moutarde pour étudier la compétition entre des plantes résistantes et des plantes sensibles indépendamment des problèmes de fitness des hybrides interspécifiques. Les plantes résistantes ont un avantage compétitif évident sous la pression d'herbivorie, et cet avantage est exacerbé sous des conditions difficiles telles que de faibles ressources du milieu et l'intensité de l'herbivorie. L'utilisation d'insectes pour attaquer des populations mixtes composées de rétrocroisements sensibles et Bt-résistants aux insectes a confirmé ce résultat et a montré que le transgène n'avait pas de coût en l'absence d'insectes. La productivité totale des populations a augmenté avec la proportion de plantes résistantes. Quatrièmement, des populations de ravenelles ont été échantillonnées dans quatre régions éloignées entre elles, dont une ayant une longue histoire de coexistence avec le colza et donc ayant plus de chance d'avoir été soumise à l'hybridation interspécifique avec le colza. J'ai interprété la divergence des traits et leur polymorphisme dans le cadre d'une hypothèse d'introgression stabilisée en opposition au simple hasard, bien que les différences avec les autres populations n'étaient pas assez marquées pour faire sortir ces populations du domaine de variation décrit pour les ravenelles. Ces études soulignent plusieurs facteurs qui peuvent accroître le risque des flux de transgènes et l'introgression entre les cultures génétiquement modifiées et leurs apparentés sauvages, et cela doit être pris en compte dans les procédures d'évaluation des risques de l'usage de ces plantes. A savoir : la morphologie cultivée qui rend confuse l'identification des introgressants dans le cadre de la bio-surveillance, les petites semences hybrides avec une dormance et une dispersion supérieures, et l'intensité de l'herbivorie et de la compétition qui exacerbe l'avantage adaptatif des plantes transgéniques résistantes aux insectes. Cependant, l'hypothèse de la formation de " super mauvaises herbes " ne semble pas justifiée.
40

Conséquences écologiques et évolutives du flux de gènes entre Brassica napus transgénique et ses apparentés sauvages / Ecological and evolutionary consequences of gene flow between transgenic Brassica napus and its wild relatives

Liu, Yongbo 29 October 2010 (has links)
Les conséquences des flux de gènes et de l’introgression entre les cultures transgéniques et leurs apparentés sauvages sont encore au cœur des débats associés à la commercialisation des plantes génétiquement modifiées. J’ai développé mon étude sur les conséquences écologiques et évolutives du flux de gènes entre le colza (Brassica napus) et ses apparentés, la moutarde brune sauvage (B. juncea) et la ravenelle (Raphanus raphanistrum), en réalisant une série d’expériences en serre, au jardin et au champ à Beijing et à Dijon. En premier, j’ai présenté une revue synthétique de la littérature publiée sur les flux de gènes et ses effets sur la fitness chez les Brassicées. En second, j’ai cherché à mettre en évidence le rôle de la taille des semences hybrides entre du colza transgénique Bt et la moutarde. La petite taille des semences a réduit les capacités de croissance et de reproduction, mais l’effet sur la fitness était variable en fonction des fonds génétiques ou spécifiques. Les rétrocroisements sur le colza étaient plus faciles et productifs que pour les autres types de descendants. La plupart de ces plantes avait une morphologie de colza. Liée à la résistance à l’herbicide, cette caractéristique pourrait permettre aux descendants de survivre dans les champs et de disséminer les transgènes aux repousses et aux autres colzas, ce qui serait peut être plus gênant que de voir l’introgression réelle dans le génome du parent sauvage. Troisièmement, j’ai simulé le phénomène d’herbivorie chez la moutarde pour étudier la compétition entre des plantes résistantes et des plantes sensibles indépendamment des problèmes de fitness des hybrides interspécifiques. Les plantes résistantes ont un avantage compétitif évident sous la pression d’herbivorie, et cet avantage est exacerbé sous des conditions difficiles telles que de faibles ressources du milieu et l’intensité de l’herbivorie. L’utilisation d’insectes pour attaquer des populations mixtes composées de rétrocroisements sensibles et Bt-résistants aux insectes a confirmé ce résultat et a montré que le transgène n’avait pas de coût en l’absence d’insectes. La productivité totale des populations a augmenté avec la proportion de plantes résistantes. Quatrièmement, des populations de ravenelles ont été échantillonnées dans quatre régions éloignées entre elles, dont une ayant une longue histoire de coexistence avec le colza et donc ayant plus de chance d’avoir été soumise à l’hybridation interspécifique avec le colza. J’ai interprété la divergence des traits et leur polymorphisme dans le cadre d’une hypothèse d’introgression stabilisée en opposition au simple hasard, bien que les différences avec les autres populations n’étaient pas assez marquées pour faire sortir ces populations du domaine de variation décrit pour les ravenelles. Ces études soulignent plusieurs facteurs qui peuvent accroître le risque des flux de transgènes et l’introgression entre les cultures génétiquement modifiées et leurs apparentés sauvages, et cela doit être pris en compte dans les procédures d’évaluation des risques de l’usage de ces plantes. A savoir : la morphologie cultivée qui rend confuse l’identification des introgressants dans le cadre de la bio-surveillance, les petites semences hybrides avec une dormance et une dispersion supérieures, et l’intensité de l’herbivorie et de la compétition qui exacerbe l’avantage adaptatif des plantes transgéniques résistantes aux insectes. Cependant, l’hypothèse de la formation de « super mauvaises herbes » ne semble pas justifiée. / In the framework of commercial release for transgenic crops with novel traits, consequences of gene flow and introgression are still one main concern. I explored the ecological and evolutionary consequences of gene flow between oilseed rape (Brassica napus) and its wild relatives, brown mustard (B. juncea) and wild radish (Raphanus raphanistrum), through several experiments carried out in greenhouse, common garden and field in Beijing and Dijon. First, I revised a comprehensive review of the literature about gene flow and its effect on plant fitness in the Brassiceae. Second, I investigated the effects on gene flow of seed size of hybrids between Bt-transgenic oilseed rape and mustard. Small seed size significantly reduced plant growth and reproduction, but its influence on plant fitness varied among genetic backgrounds. Backcrosses to oilseed rape were easier and more productive than other types of progeny of hybrids. Most of these plants exhibited oilseed rape morphology. Together with herbicide-resistance, this trait could help the progeny to survive in the field and disseminate the transgene to volunteers and feral populations, which could be more troublesome than completing introgression into the genome of the wild parent species. Third, I simulated herbivory on mustard to study the competition between insect-resistant and susceptible plants independently to the fitness of the interspecific hybrid. Resistant plants held a competitive advantage under herbivory pressure, and this advantage was magnified in harsh conditions, such as low resources and high simulated herbivory pressure. The use of insects to attack mixed populations composed of transgenic Bt-resistant and susceptible backcrosses confirmed the same conclusion and provided evidence of no cost due to the transgene in the absence of insect. The overall population production increased with the increasing proportion of insect-resistant plants in the presence of insects. Fourth, wild radish populations were sampled from four geographically distant regions, of which one region had a long history of oilseed rape cultivation, and, therefore, higher chance to have been submitted to interspecific hybridization with the crop. Traits divergence and polymorphism in the putative introgressed populations could be supported as alternate hypothesis to random variation, although the differences were not marked enough to place these populations out of the range of variation described in wild radish. These studies pointed out different factors that could enhance the risk of transgenic flow and introgression from transgenic crops to wild relatives, and they must be taken into account in the risk assessment of the use of GM crops: crop traits to identify the hybrid progeny and perform monitoring, small seed size to account for seed dispersal and dormancy, and intensity of herbivory and competition that magnify the fitness advantage of insect-resistant transgenic plants. However, the impact of introgression to create super-weeds was not supported.

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