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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.
201

Nutrição e produção de alface americana em função da vazão, periodicidade de exposição e condutividade elétrica da solução nutritiva em sistema hidropônico / Nutrition and lettuce production as a function of flow rate, periodicity of exposure and electrical conductivity of the nutrient solution in a hydroponic system

Dalastra, Cleiton [UNESP] 31 August 2017 (has links)
Submitted by CLEITON DALASTRA null (sauems@gmail.com) on 2017-10-29T21:52:25Z No. of bitstreams: 1 Cleiton Dalastra_29_10_2017_ PG Agronomia.pdf: 4821380 bytes, checksum: fad04c9fa5853e9c381aeb892db6a996 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-11-09T15:35:04Z (GMT) No. of bitstreams: 1 dalastra_c_dr_ilha.pdf: 4821380 bytes, checksum: fad04c9fa5853e9c381aeb892db6a996 (MD5) / Made available in DSpace on 2017-11-09T15:35:04Z (GMT). No. of bitstreams: 1 dalastra_c_dr_ilha.pdf: 4821380 bytes, checksum: fad04c9fa5853e9c381aeb892db6a996 (MD5) Previous issue date: 2017-08-31 / A produção de alimento face a demanda mundial é um desafio para este século, devendo-se, obrigatoriamente, destinar atenção ao ganho de eficiência produtiva, incorporada as tecnologias disponíveis. Dentre as hortaliças folhosas, a alface se destaca em toda culinária global. A produção atual da alface tem passado por grandes avanços, atribuídos especialmente à técnica de produção hidropônica, contudo, ainda é necessita melhorias na adaptabilidade da tecnologia hidropônica às condições climáticas das diversas regiões e às diferentes necessidades da gama de cultivares presentes no mercado. Neste cenário, a proposição desta pesquisa surge em resposta à demanda de informações pelo setor produtivo, cumprindo seu papel na integração entre ensino, pesquisa e extensão rural, de maneira a contribuir modestamente com o setor produtivo. Para isso, foram realizados três experimentos isolados em sistema hidropônico NFT (Técnica de Fluxo Laminar de Nutrientes), com o objetivo de avaliar a nutrição e a produção econômica de alface americana em função da vazão, periodicidade de exposição e condutividade elétrica da solução nutritiva, respectivamente. O delineamento experimental foi em blocos casualisados, com cinco repetições e cada tratamento foi composto por 15 plantas. No experimento 1, os tratamentos utilizados constaram da aplicação de solução nutritiva nas vazões de 0,5; 1; 2 e 4 litros por minuto em cada canal de cultivo. No experimento 2, os tratamentos foram quatro combinações de intermitência de exposição da solução nutritiva em intervalos de bombeamento / intervalo de ausência de bombeamento em minutos: 15/60; 15/30; 15/15 e FI (Fluxo initermitente). No experimento 3, os tratamentos foram a manutenção diária da solução nutritiva em quatro valores de condutividade elétrica, de 0,8; 1,3; 1,8 e 2,3 dS m-1, em função da concentração de nutrientes. A maior produção e lucratividade de alface americana foi obtida com a vazão da solução nutritiva de 1 L/min, devido ao maior acúmulo de nutrientes na parte aérea e eficiência de sua utilização; também houve a maior produção e lucratividade de alface americana obtida com fluxo contínuo da solução nutritiva (FI), devido ao maior acúmulo de nutrientes na parte aérea e raízes, maior assimilação de nitrato e eficiência de utilização de nutrientes; economicamente, a condução em intervalo 15/30 minutos acarreta em prejuízo financeiro; o acompanhamento dos tratamentos de condutividade elétrica no decorrer do ciclo da alface aponta para produção superior com condutividade elétrica recomendada por fase de cultivo, sendo: 0,8 dS m-1 até os 10 dias após o transplantio (DAT); 1,30 dS m-1 dos 10 aos 17 DAT; 1,80 dS m-1 dos 17 aos 24 DAT e 1,30 dS m-1 dos 24 aos 31 DAT. / The food production to meet global demand is a challenge for this century, should be compulsorily intended attention to productive efficiency gains incorporated the available technologies. Among the leafy vegetables, the lettuce stands out in all global cuisine. The current production of lettuce has undergone great advances, especially attributed to the hydroponic production technique. However, it is still necessary to improve the adaptability of hydroponic technology to the climatic conditions of the different regions and to the different needs of the wide range of cultivars present in the market. In this scenario, the proposition of this research arises in response to the demand for information by the productive sector, fulfilling its role in the integration between teaching, research and rural extension, in order to contribute modestly with the productive sector. For that, three experiments were carried out in a NFT hydroponic system, with the objective of evaluating the nutrition and economic production of American lettuce as a function of flow rate, periodicity of exposure and electrical conductivity of the nutrient solution, respectively. The experimental design was in randomized blocks, with five replicates and each treatment consisted of 15 plants. In the experiment 1, the treatments used consisted of the application of nutrient solution at the flow rates of 0.5; 1; 2 and 4 liters per minute in each culture channel. In experiment 2, the treatments were four combinations of intermittent exposure of the nutrient solution at pumping intervals / no pumping interval in minutes: 15/60; 15/30; 15/15 and 15/0. In experiment 3, the treatments were daily maintenance of the nutrient solution in four values of electrical conductivity, of 0.8; 1,3; 1.8 and 2.3 dS m-1, depending on the concentration of nutrients. The conclusions were: The highest production and profitability of American lettuce was obtained with the flow of the nutrient solution of 1 L/min, due to the greater accumulation of nutrients in the aerial part and efficiency of use of these; The highest production and profitability of American lettuce was with cycles of 15/0 minutes, that is, with continuous flow of the nutrient solution due to the greater accumulation of nutrients in the aerial part and efficiency of use of these; Economically, driving in interval 15/30 minutes under the conditions studied, does not supply the cost of production and entails financial loss; The treatments were monitored during the lettuce cycle, indicating a higher yield than the one obtained with the recommended electrical conductivity at each cultivation stage: 0.8 dS m-1 until 10 days after transplanting (DAT) of lettuce; 1.30 dS m-1 from 10 to 17 DAT; 1.80 dS m-1 from 17 to 24 DAT and 1.30 dS m-1 from 24 to 31 DAT.
202

Produção, fisiologia e qualidade pós-colheita da alface ‘Elba’ produzida sob adubação foliar com Spirulina platensis. / Production and lettuce postharvest quality 'Elba' produced applying foliar based on Spirulina platensis.

SILVA, Débora Samara Oliveira e. 17 May 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-05-17T18:00:18Z No. of bitstreams: 1 DÉBORA SAMARA OLIVEIRA E SILVA - DISSERTAÇÃO PPGHT 2015..pdf: 2291176 bytes, checksum: 68508f58ce13106f63abc44d962e1a93 (MD5) / Made available in DSpace on 2018-05-17T18:00:18Z (GMT). No. of bitstreams: 1 DÉBORA SAMARA OLIVEIRA E SILVA - DISSERTAÇÃO PPGHT 2015..pdf: 2291176 bytes, checksum: 68508f58ce13106f63abc44d962e1a93 (MD5) Previous issue date: 2015-03-30 / A alface (Lactuca sativa L.) é a hortaliça folhosa mais produzida e consumida no Brasil, no entanto, necessita receber nutrientes que permitem o seu desenvolvimento. Desta forma, tornam-se necessários estudos sobre o uso de fontes orgânicas de adubo, como os biofertilizantes, e sua influência sobre os aspectos morfofisiológicos e de qualidade. Neste sentido, objetivou-se avaliar o efeito de diferentes concentrações de Spirufert® (fertilizante orgânico simples classe “A”, marca Tamanduá) sob a produção, fisiologia e qualidade póscolheita da alface „Elba‟. O experimento foi realizado em duas etapas no Centro de Ciências e Tecnologia Agroalimentar, em Pombal-PB. Na primeira etapa, estudou-se em condições de campo, no delineamento em blocos casualizados, o efeito de seis concentrações do Spirufert ® (0, 1,5, 3,0, 4,5, 6,0 e 7,5 %) distribuídos em seis blocos, sob aspectos de produção e fisiologia das mudas de alface. Na segunda etapa, analisada em laboratório, adotou-se o delineamento inteiramente casualizado, em parcelas subdivididas no tempo, com seis repetições. As parcelas foram constituídas pelas seis concentrações de Spirufert®, aplicadas durante o cultivo da alface, e as subparcelas, pelas épocas de avaliação (por ocasião da colheita e 24h após a permanência das alfaces sob prateleira em ambiente climatizado a 26°C). Não houve efeito significativo das concentrações de Spirufert® para as variáveis, número de folhas (NF), massa fresca da parte aérea (MFPA), altura de plantas (AP) e diâmetro da copa (DC), massa seca (MSPA), umidade (UMPA), massa fresca do sistema radicular (MFSR), comprimento de raiz (CR), massa seca do sistema radicular (MSSR), massa fresca total da planta (MFTP) e massa seca total da planta (MSTP) da parte aérea das plantas de alface. Da mesma forma, as concentrações de Spirufert® testadas não alteram o teor de N, P, K e Na, fotossíntese, concentração interna de CO2 e condutância estomática da parte aérea da alface. Houve efeito significativo entre as concentrações de Spirufert ® e as épocas de avaliação, no dia da colheita e 24h após a colheita da alface para a maioria das variáveis analisadas. Constatou-se maior média de SS na dose 4,5% de Spirufert®, na ordem de 4,16%, porém redução deste valor após 24h, em que se observou sinais de senescência nas alfaces, constatados pelo aumento da acidez titulável. Na dose 4,5% de Spirufert®, também observouse uma boa relação SS/AT e elevado teor de clorofila total, mesmo após 24 h, fato que possibilitou a manutenção da coloração verde nas folhas, característica apreciada pelo consumidor, por ocasião da aquisição. / Lettuce (Lactuca sativa L.) is the most widely produced and consumed leafy vegetable in Brazil, however, needs to receive nutrients that allow its development. In this way, it becomes necessary studies on the use of organic sources of fertilizer, such as biofertilizers, and its influence on the morphophysiological aspects and quality. In this sense, the objective was to evaluate the effect of different concentrations of Spirufert® (simple organic fertilizer class "A", anteater brand) in the production, physiology and lettuce postharvest quality 'Elba'. The experiment was conducted in two stages in the Science and Technology Centre Agrifood in Pombal-PB. In the first stage, was studied under field conditions in a randomized block design, the effect of six concentrations Spirufert ® (0, 1.5, 3.0, 4.5, 6.0 and 7.5%) distributed in six blocks, under aspects of production and physiology of lettuce seedlings. In the second stage, was analyzed in a laboratory, adopted a completely randomized design in split plot with six replications. The plots were made by the six concentrations of Spirufert®, applied for the cultivation of lettuce, and the subplots, the evaluation periods (at harvest and 24 hours after the permanence of lettuce under shelf in air-conditioned environment at 26 ° C). There was no significant effect of Spirufert® concentrations for the variables, number of leaves (NF), fresh weight of aerial part (MFPA), plant height (PH) and crown diameter (DC), dry matter (MSPA), humidity (umpa), fresh weight of the root system (MFSR), root length (CR), dry mass of the root system (MSSR), fresh pasta total plant (MPTP) and total dry mass of the plant (MSTP) of the aerial part lettuce plants. Similarly, the Spirufert® concentrations tested did not alter the content of N, P, K and Na, photosynthesis, internal CO2 concentration and stomatal conductance of the aerial part of lettuce. Significant differences were found between the Spirufert ® concentrations and the evaluation periods, the day of harvest and 24h after the lettuce harvest for most variables. It was found SS higher average dose 4.5% of Spirufert® in the order of 4.16%, but this value reduction after 24 hours, it was observed that the lettuce signs of senescence, evidenced by increased acidity. At a dose of 4.5% Spirufert® also there was a good SS / TA ratio and high content of chlorophyll, even after 24 h, a fact that enabled the maintenance of green color in the leaves, characteristic appreciated by the consumer on the occasion the acquisition.
203

Adubação nitrogenada no consórcio alface e rúcula /

Barros Júnior, Aurélio Paes. January 2008 (has links)
Resumo: Com o objetivo avaliar a influência de doses de nitrogênio realizadas para a alface e/ou para a rúcula, em consórcio, sobre as plantas (estado nutricional e crescimento) e sobre o consórcio (produtividade, classificação e qualidade, uso eficiente da área e rentabilidade), foi realizado um experimento no período de setembro à dezembro de 2006, na Unesp, Campus de Jaboticabal-SP. O delineamento experimental foi o de blocos casualizados completos, com quatro repetições, sendo os tratamentos arranjados em esquema fatorial 4 x 4 + 2. Os tratamentos resultaram da combinação de quatro doses de N para a alface (0, 65, 130 e 195 kg/ha de N) e quatro doses de N para a rúcula (0, 65, 130 e 195 kg/ha de N), mais dois tratamentos adicionais, correspondentes às monoculturas de alface e rúcula. As cultivares utilizadas foram Verônica (alface) e Folha Larga (rúcula). Para todas as características avaliadas de plantas de alface a monocultura (testemunha) tiveram melhor desempenho que em consórcios, não ocorrendo diferenças para as características de rúcula. O aumento da dose de N para ambas as culturas, em consórcio, proporcionou incrementos nas características de plantas de alface e rúcula. A máxima produtividade de alface, 23.744,48 kg/ha, foi obtida com 100 kg/ha de N para alface e 195 kg/ha de N para rúcula. A máxima produtividade de rúcula, 14.435,78 kg/ha, foi obtida com a adubação de 195 kg/ha de alface e 180 kg/ha de N para rúcula. A maximização do índice de eficiência de uso da área (1,86) foi obtido na dose 127 kg/ha N para a alface e 195 xv kg/ha N para rúcula. O maior lucro operacional, R$ 29.026,11/ha, foi obtido na combinação de doses de 122 kg/ha N para alface e 195 kg/ha N para rúcula. / Abstract: In order to evaluate the influence how nitrogen rates used for lettuce and/or rocket, under intercropping, affect the plants (nutrition and growth conditions), and the intercropping (yielding, grading, land equivalent ratio and profitability), an experiment was carried out at the campus of Unesp in Jaboticabal-SP, from September to December 2006. The experiment was conducted in a randomized complete block design, with four replications, treatments being arranged in a 4 x 4 + 2 factorial design. The treatments were the result of a combination of four N rates for lettuce (0, 65, 130 and 195 kg/ha of N), and four N rates for rocket (0, 65, 130 and 195 kg/ha of N), plus two additional treatments, which corresponded to lettuce and rocket under single cropping. Veronica (lettuce) and Folha Larga (rocket) were the cultivars used. For all the plant characteristics of lettuce that were studied, the single cropping (witness) had better performance than in intercropping, whereas no differences were observed for the rocket characteristics. An increase in the N rate for both cultures under intercropping showed gains in the plant characteristics of lettuce and rocket. Maximum lettuce yield, 23,744.48 kg/ha, was achieved with the application of 100 kg N ha for lettuce, and 195 kg N ha for rocket. Maximum rocket yield, 14,435.78 kg/ha, was achieved with the application of 195 kg N ha for lettuce, and 180 kg N ha for rocket. The land equivalent ratio was maximized (1.86) by using 127 kg N ha for lettuce and 195 kg N ha for rocket. The highest xvii operating profit, R$ 29,026.11/ha, resulted from the combination of 122 kg N ha for lettuce and 195 kg N ha for rocket. / Orientador: Arthur Bernardes Cecílio Filho / Coorientador: Renato de Mello Prado / Coorientador: José Carlos Barbosa / Banca: Francisco Bezerra Neto / Banca: Leilson Costa Grangeiro / Banca: Domingos Fornasieri Filho / Banca: José Ricardo Mantovani / Doutor
204

Controle de viroses em alface por meio de métodos integrados de manejo da cultura /

Borges, Luciana Maestro, 1972- January 2006 (has links)
Orientador: Marcelo Agenor Pavan / Banca: Rumy Goto / Banca: Norberto da Silva / Banca: Alexandre de Moura Guimarães / Banca: Eliezer Rodrigues de Souto / Resumo: O trabalho teve como objetivos avaliar diversas progenies de alface da geracao [(Brasil 303 x Tinto) Elisa] F5 RC1, previamente selecionadas para tolerancia a "Lettuce mosaic virus" - (LMV-II), "Lettuce mottle virus" (LeMoV) e Tospovirus e o efeito de diferentes praticas culturais no controle de fitovirus na cultura da alface, em duas epocas do ano (outono/inverno e primavera/verao). Os fatores avaliados foram: cobertura do solo (palha de arroz e sem cobertura), cultivo protegido (tunel coberto com filme PEBD aditivado antivirus de 150 æm e tunel coberto com tela anti-afideo) e 18 progenies, avaliando os seguintes aspectos agronomicos: area de projecao da copa, massa fresca da parte aerea da planta, produtividade, fechamento de "cabeça", tempo de inicio do pendoamento e incidencia de fitoviroses. A avaliacao da incidencia de fitovirus na cultura foi realizada atraves de observacao visual dos sintomas, sendo que amostras de plantas que apresentavam sintomas foram coletadas e examinadas atraves de testes moleculares de diagnose especificos para LMV-II, LMV-IV, LeMoV e Tospovirus. Para algumas amostras sintomaticas negativas ainda foram realizados testes de RT-PCR para possivel deteccao de "Cucumber mosaic virus". (CMV), testes de inoculacao mecanica em hospedeiras diferenciadoras e analises de microscopia eletronica. Quanto aos aspectos agronomicos das progenies, observou-se que o tratamento "palha de arroz"apresentou resultado superior aos demais tratamentos para as caracteristicas massa fresca e produtividade e igual desempenho ao tratamento "solo nu" para as caracteristicas fechamento de "cabeça" e tempo de inicio de pendoamento. Dentre as 2 progenies testadas, se destacaram as de numero 6 e 7 por apresentarem maior tolerancia a viroses e caracteristicas agronomicas equivalentes a cultivar comercial utilizada como controle. Na avaliacao visual de fitoviroses... / Abstract: The research aimed to evaluate various progenies, obtained from the crossing of [(Brasil 303 x Tinto) Elisa] F5 RC1, previously selected for tolerance to "Lettuce mosaic virus" - (LMV-II), "Lettuce mottle virus" (LeMoV) and tospovirus and the effect of different phytovirus control practices in lettuce, in two periods of the year (autumn/winter and spring/summer). The factors evaluated were: soil covering (straw of rice and bare soil); protected development with a tunnel covered with an anti-virus PEBD treated film of 150 ìm and a tunnel covered with anti-aphid screen; and 18 progenies, evaluating the following agronomic aspects: area of top projection, fresh mass of the aerial part of the plant, productivity, closing of "head" and time at the beginning of tasselling and incidence of phytovirosis. The evaluation of phytovirus incidence in the crop was accomplished through visual observation of symptoms. Samples of plants showing symptoms were collected and taken to the laboratory for molecular tests to specifically detect LMV-II, LMV-IV, LeMoV and tospovirus. For some negative symptomatic samples, tests of RT-PCR were accomplished to detect possible infection by "Cucumber mosaic virus"- (CMV), and mechanical inoculation tests in differential plant, and electronic microscopic analysis. As for the agronomic aspects of the progenies, it was observed that the "rice straw" treatment presented better results than other the treatments for the fresh mass and productivity parameters, and equal performance on the "bare soil" treatment for the parameters closing of "head" and time at the beginning of tasseling. Among the tested progenies, number 6 and 7 were distinguished for presenting better tolerance to phytovirosis and agronomic characteristics equivalent to the commercial cultivar used as control. In the visual evaluation of phytovirosis, it was verified that 3,65%... / Doutor
205

Gestion des bio-agresseurs et réduction des pesticides en culture de laitue sous abris froids : apports croisés d’expérimentations factorielles et systémiques / Pesticide reduction and management of lettuce pests and pathogens

Barrière, Virginie 06 March 2015 (has links)
La réduction de la dépendance aux pesticides des systèmes de culture de laitue constitue un objectif à relativement court terme, partagé par les pouvoirs publics et les acteurs de la filière de production. Atteindre cet objectif suppose de disposer de moyens techniques permettant de substituer aux pesticides d’autres méthodes limitant les dégâts de bio-agresseurs de la laitue.Ces techniques peuvent être destinées à minimiser l’entrée d’inoculum dans les parcelles, à limiter la propagation des bio-agresseurs, à diminuer la sensibilité des plantes, ou à éradiquer les bio-agresseurs présents sur les cultures. L’évolution des systèmes de culture repose sur la démonstration de l’efficacité, en termes de protection des plantes, de ces techniques alternatives aux pesticides lorsqu’elles sont intégrées et combinées dans les itinéraires techniques. Elle dépend aussi de l’impact socio-économique et environnemental des itinéraires techniques alternatifs, dans un contexte commercial et réglementaire exigeant. L’objet de cette thèse a été de développer des stratégies alternatives de gestion des bio-agresseurs de la laitue d’hiver cultivée sous abri froid,plus économes en pesticides, et d’évaluer leurs performances agronomiques, économiques et environnementales,garantes de la durabilité des systèmes de production.Sur la base des techniques déjà disponibles, deux stratégies alternatives, nommées stratégie intermédiaire et stratégie bas-intrant ont été conçues, et testées dans deux exploitations agricoles et un domaine expérimental de l’INRA pendant deux hivers, en comparaison avec une stratégie conventionnelle, représentative des pratiques actuelles. Les stratégies intermédiaire et bas-intrant ont permis de réduire de 32% et 48% l’usage des pesticides, respectivement, et ont été suffisamment efficaces pour obtenir une qualité visuelle et des rendements équivalents à la stratégie conventionnelle. Le bénéfice environnemental de leur mise en oeuvre a également été démontré. La mise en place de ces stratégies a cependant entrainé un surcoût de production,essentiellement lié à la lutte biologique, d’environ 10 à 13%. Parallèlement, deux orientations techniques originales, dont l’efficacité n’était pas caractérisée, ont été explorées. Une première série d’essais expérimentaux a porté sur l’influence du génotype de l’hôte et de l’environnement de la plante sur sa sensibilité à deux champignons pathogènes d’importance majeure, Botrytis cinerea et Sclerotinia sclerotiorum. Il a été montré que le choix d’un génotype moins sensible couplé à une optimisation du rapport fructose : saccharose de la plante diminuait les symptômes observés après inoculation. Une deuxième démarche expérimentale, portant sur la lutte biologique contre le puceron Nasonovia ribisnigri, a révélé l’incapacité de parasitoïdes du genre Aphidius à contrôler les pucerons en fin de culture, lorsque la structure du couvert végétal devient trop complexe.En plus d’inscrire ces travaux de recherche dans un processus d’amélioration continue de l’efficacité et des performances des stratégies alternatives aux pesticides, la démarche scientifique utilisée, articulant approche analytique et approche intégrative, a permis d’étudier des techniques ayant potentiellement un impact sur plusieurs bio-agresseurs, telles que la réduction de la fertilisation azotée ou l’optimisation de l’espacement entre les laitues, qui pourraient permettre une meilleure gestion des pathogènes responsables de la pourriture du collet et des pucerons. / The reduction of pesticide reliance in lettuce cropping systems is a short term objective sharedby public authorities and by the stakeholders of lettuce market. Reaching this goal implies thesubstitution of pesticides by others techniques which may limit pest and pathogen damage. Thesetechniques can be intended to mitigate pest and pathogen invasion or propagation, to increaseplant defenses or to remove pests and pathogens from the crop. The improvement of currentcropping systems relies on i) the demonstration of the ability of alternative techniques to managediseases and pests when they are combined and integrated during the crop cycle; ii) theassessment of the socio-economic and environmental impacts of alternative strategies in a stringentcommercial and regulatory context. The objective of this thesis was to design alternativestrategies for pest and pathogen management of lettuce grown in winter under shelter, with fewerpesticide applications, and to assess their agronomic, economic and environmental performancesso as to ensure the sustainability of production.Based on currently available techniques, two alternative strategies, called intermediate andlow-input, were designed, and tested in two farms and an INRA experimental station duringtwo winters and compared to a conventional strategy representing current practices. The alternativestrategies enabled to reduce pesticide applications by 32% and 48% respectively. Theywere efficient enough to obtain similar yield and quality as compared to the conventional strategy.The environmental benefits of their implementation were also demonstrated. However, thesestrategies required a 10-13% extra production costs, almost exclusively due to biological controlproducts.In parallel, two original technical orientations, which efficacy had not been previously described,were examined. In a first set of experiments, the impact of lettuce genotype and growthconditions on plant susceptibility to two major pathogens, Botrytis cinerea and Sclerotinia sclerotiorum,was investigated. The use of a genotype displaying low susceptibility to these fungi,associated with an optimization of the ratio of fructose : sucrose in plants, appeared to reducethe symptoms after inoculation. A second experimental approach, dealing with biological controlagainst the aphid Nasonovia ribisnigri, highlighted the inability of Aphidius parasitoids tocontrol aphid populations at the end of the crop cycle, when the canopy structure becomes toocomplex.In addition to a contribution to cropping systems improvement, the scientific method used,combining analytical and integrative approaches enabled us to highlight the effect of techniquesacting on several pests and/or pathogens, such as the reduction of nitrogen fertilization or theoptimization of plant spacing, which could improve the management of fungi causing basal rotas well as aphids.
206

Doses de fósforo no acúmulo de nutrientes, na produção e na qualidade de sementes de alface /

Kano, Cristiaini, 1977- January 2006 (has links)
Resumo: Devido à escassez de informações relacionadas ao efeito da adubação na produção e qualidade de sementes de hortaliças, principalmente nas espécies que possuem aumento no ciclo com o estádio reprodutivo, nota-se a necessidade de determinar a demanda nutricional e a dose dos nutrientes para auxiliar na recomendação de adubação que proporcione a melhor produtividade de sementes de boa qualidade. Este trabalho foi conduzido na Fazenda Experimental São Manuel - UNESP/FCA, São Manuel/SP, localizada à latitude sul de 22o 46’, longitude oeste de 48º 34’ e altitude de 740 m, no período de 25/09/03 a 19/02/04, com o objetivo de determinar as curvas de acúmulo de nutrientes e avaliar a resposta de doses de fósforo adicionados ao solo na produção e qualidade de sementes de alface cultivar Verônica. O delineamento experimental utilizado foi blocos casualizados, com cinco tratamentos (0; 200; 400; 600 e 800 kg ha-1 de P2O5) e cinco repetições. Foram avaliadas características vegetativas das plantas, acúmulo e teor dos nutrientes no caule + folhas + hastes florais e nas sementes, a produção de sementes (massa e número) por planta e a sua qualidade (germinação e vigor). Os dados foram submetidos às análises de variância e de regressão. Observaram-se aumento linear na massa verde e massa seca das plantas no final do ciclo, com o aumento das doses de P2O5. A ordem decrescente dos nutrientes acumulados pela parte aérea total das plantas de alface para a produção de sementes foi: potássio > nitrogênio > cálcio > magnésio > fósforo > enxofre > ferro > manganês > zinco > boro > cobre e nas sementes essa ordem foi: nitrogênio > fósforo > potássio > magnésio > cálcio > enxofre > ferro > zinco > 2 manganês > cobre > boro. O período de maior demanda da maioria dos macronutrientes foi entre o início do pendoamento e o início do florescimento... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Due to the lack of information about the fertilization effect in vegetable seed production and quality, mainly in the species that have an increase cycle in the reproductive stage, a need has been identified to evaluate the nutritional demand and nutrient level to aid in recommending fertilization that provides best productivity from high quality seeds. This study was carried out from September/2003 to February/2004 at São Manuel Experimental Farm UNESP/FCA, in São Manuel, São Paulo State, Brazil, at 22o 46’ south latitude, 48º 34’ west longitude and at an altitude of 740 m, with the objective to evaluate the nutrients accumulation curves and response of phosphorus added to the soil on the seed production and seed quality of lettuce cultivar Verônica. The experiment was conducted in randomized complete blocks, with five treatments (0; 200; 400; 600; 800 kg ha-1 of P2O5) and five replications. Plant vegetative characteristics, nutrients (accumulation and content) in stem + leaves + flower stalks and seeds, seed yield (mass and number per plant) and seed quality (germination and vigor) were evaluated. The data were submitted to variance and regression analysis. A linear increase in plant fresh mass and plant dry mass was verified at the end of the cycle along with increased P2O5 rates. Nutrients accumulated in the total aerial part of the lettuce plant for seed production were, in descending order: potassium > nitrogen > calcium > magnesium > phosphorus > sulphur > iron > manganese > zinc > boron > copper, while in the seeds the order was: nitrogen > phosphorus > potassium > magnesium > calcium > sulphur > 4 iron > zinc > manganese > copper > boron. The period with the biggest demand for majority of the macronutrients was from the beginning of the stem elongation stage to the beginning of the flowering stage and for the majority of micronutrients, after the beginning of the flowering stage... (Complete abstract, click electroni address below) / Orientador: Antonio Ismael Inácio Cardoso / Coorientador: Roberto Lyra Villas Bôas / Banca: Antonio Celso Wagner Zanin / Banca: Dirceu Maximino Fernandes / Banca: Arthur Bernardes Cecilio Filho / Banca: Simone da Costa Mello / Doutor
207

Doses de composto orgânico, com e sem fósforo adicionado ao solo, na produção e qualidade de sementes de alface /

Quadros, Bárbara Rodrigues de, 1984. January 2010 (has links)
Orientador: Antonio Ismael Inácio Cardoso / Banca: Giuseppina Pace Pereira Lima / Banca: João Nakagawa / Banca: Sérgio Antonio Lopes de Gusmão / Resumo: Devido à escassez de informações relacionadas ao efeito da adubação na produção e qualidade de sementes de hortaliças, nota-se a necessidade de determinar a demanda nutricional e a dose dos nutrientes para auxiliar na recomendação que proporcione a melhor produtividade de sementes de boa qualidade. Este trabalho foi conduzido em vaso na Fazenda Experimental São Manuel - UNESP/FCA, São Manuel/SP, com o objetivo de avaliar a resposta a doses de composto orgânico, com e sem fósforo adicionado ao solo, na produção e qualidade de sementes de alface crespa cultivar Verônica. O delineamento experimental foi em blocos casualizados, com dez tratamentos (0; 20; 40; 60; 80 t ha-1 de composto orgânico, com e sem 400 kg ha-1 de P205) e quatro repetições. Foram avaliadas características vegetativas das plantas, teor dos nutrientes no caule + folhas + hastes florais, acúmulo e teor de nutrientes nas sementes, produção de sementes (massa e número) por planta e a sua qualidade (germinação e vigor). Os dados foram submetidos às análises de variância e de regressão. A aplicação de fósforo aumentou a produção de sementes. Na presença de fósforo, a dose de 33,4 t ha-1 de composto orgânico, e na ausência de fósforo, a dose de 49,21 t ha-1 proporcionaram maior massa de sementes por planta. A qualidade das sementes não foi afetada tanto pela adubação com composto orgânico como com fósforo. A ordem decrescente dos nutrientes acumulados pelas sementes foi: nitrogênio > fósforo > potássio > cálcio > magnésio > enxofre > ferro > manganês > zinco > boro > cobre. / Abstract: Due to the scarcity of information regarding the effect of fertilization on yield and quality of vegetable seeds, there is a need to determine nutrient demand and the level of nutrients to support the recommendation that gives the best yield of good quality seeds. This study was conducted out in pots at the Experimental Farm São Manuel - UNESP / FCA, São Manuel / SP, in order to evaluate levels of organic compost, with and without phosphorus added to soil, on yield and quality of lettuce seeds cultivar Veronica. The experimental design was randomized blocks with ten treatments (0, 20, 40, 60, 80 t ha-1 of organic compost, with and without 400 kg ha-1 P205) and four replicates. It was evaluated vegetative characteristics of plants, nutrients content in stems + leaf + flower stalks, accumulation and nutrient content in seeds, seed production (weight and number) per plant and quality (germination and vigor). The data were submitted to analysis of variance and regression. Phosphorus application increased seed production. In the presence of phosphorus the level of 33, 4 t ha-1 of organic compost and in the absence of phosphorus the level of 49,21 t ha-1 resulted higher seed weight per plant. The quality of seeds was not affected by fertilization with organic compost on with phosphorous. The order of nutrient uptake by seeds was: nitrogen> phosphorus> potassium> calcium> magnesium> Sulfur> iron> manganese> zinc> boron> copper. / Mestre
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Polluants organiques : analyse, application au « biomonitoring » environnemental et introduction des biopesticides (algues marines) comme alternative / Organic pollutants : analysis, application to environmental biomonitoring and introduction of biopesticides (marine algae) as an alternative

Al-Alam, Joséphine 05 July 2017 (has links)
Dans un contexte où les inquiétudes environnementales dues à la pollution sont grandissantes à l’échelle globale, la surveillance de la pollution environnementale constitue un enjeu majeur de recherche afin de préserver au mieux un environnement sain et durable. En effet, la surveillance responsable et continue de l’environnement accompagnée par le développement d’alternatives de lutte « verte » contre les nuisibles, pourrait certainement ralentir voir inhiber la propagation de polluants néfastes pour l’ensemble de la biosphère. Dans ce contexte, les objectifs principaux de cette thèse visent d’une part à caractériser la qualité de l’air par une approche basée sur le biomonitoring, et d’autre part à développer un biopesticide d’origine algale permettant la protection des agrumes en post-récolte comme un exemple d’alternative à l’usage des traitements chimiques classiques. Pour répondre au premier objectif, des méthodes d’extraction multi résidus ont dû être développées. Ces méthodes ont été soit spécifiques d’une famille de pesticides tel que les dithiocarbamates, soit plus large et plus générale en considérant de nombreux polluants comme des pesticides, des HAPs et des PCBs. Ces dernières ont été basées soit sur l’ASE-SPE-SPME, soit sur le QuEChERS-SPME, et ont formé le socle des études de biosurveillance environnementale entreprises. Ces études de surveillance ont permis l’évaluation des modifications spatio-temporelles de la qualité de l’air grâce à des espèces naturelles ayant un rôle de capteurs biologique de la pollution environnementale et permettant par la suite l’estimation de la pollution dans des zones bien définies. Pour répondre au second objectif, des extraits aqueux d’algues vertes, Ulva linza et Ulva lactuca, ont été préparés et testés comme antifongiques in vivo et in vitro afin d’étudier leur aptitude à inhiber le développement de Penicillium digitatum sur des agrumes en post récolte. Un potentiel de protection des agrumes en poste-récolte contre ce champignon a été mis en évidence, donnant effectivement l’espoir à la fiabilité de cette approche comme alternative biologique pour le remplacement des pesticides chimiques potentiellement toxiques. / In a context where environmental concerns due to pollution are growing on a global scale, monitoring of environmental pollution is a major research challenge in order to preserve as much as possible a healthy and sustainable environment. Indeed, the responsible and continuous monitoring of the environment escorted by the development of "green" pest control alternatives could certainly decelerate or even inhibit the spread of harmful pollutants into the entire biosphere. In this context, the main objectives of this thesis are intended firstly to characterize air quality by a biomonitoring-based approach and, secondly, to develop a biopesticide of algal origin, that allows the protection of post-harvested citrus fruit, as an alternative to the use of conventional chemical treatments. In order to answer the first objective, multi-residues extraction methods were developed. These methods were either specific to a family of pesticides such as dithiocarbamates or wider and more general regarding numerous pollutants such as pesticides, PAHs and PCBs. The latter were based either on the ASE-SPE-SPME, or on the QuEChERS-SPME, and formed the base of environmental biomonitoring studies undertaken. These monitoring studies allowed the assessment of spatial and temporal changes in air quality through natural species acting as biological sensors of environmental pollution and subsequently allowing the estimation of pollution in well-defined areas. To answer the second objective aqueous extracts of green algae, Ulva linza and Ulva lactuca, were prepared and tested as in vivo and in vitro antifungal agents, in order to study their ability to inhibit the development of Penicillium digitatum on post-harvested citrus fruits. A potential of post-harvested citrus fruits’ protection against this fungus was proved, giving hope to the reliability of this approach as a biological alternative for the replacement of potentially toxic chemical pesticides.
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Irriga??o automatizada com d?ficit controlado em alface em ambiente protegido: produ??o em vasos e em bandejas / Automated irrigation with deficit controlled in lettuce in greenhouse: production in pots and trays

Valen?a, David da Cunha 24 February 2016 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-01-09T11:54:46Z No. of bitstreams: 1 2016 - David da Cunha Valen?a.pdf: 2653024 bytes, checksum: d2b4461225be75ec25872fbc06de8bdb (MD5) / Made available in DSpace on 2017-01-09T11:54:46Z (GMT). No. of bitstreams: 1 2016 - David da Cunha Valen?a.pdf: 2653024 bytes, checksum: d2b4461225be75ec25872fbc06de8bdb (MD5) Previous issue date: 2016-02-24 / Funda??o Carlos Chagas Filho de Amparo ? Pesquisa do Estado do RJ - FAPERJ / The concern with the intensive use of natural resources has become increasingly justifying the development of new technologies aiming their rational use such as automated irrigation systems. The automation of irrigation could to allow water saving increasing efficiency of its use in agricultural production. The first chapter of this study was to evaluate five different volumes (130, 100, 80, 60 and 33% of volume of Simplified Irrigation Controller - SIC) in the production of lettuce in pots in a production system called "Organic Potponics". It was used the SIC, whose operation is based on tension in the soil solution. The different volumes were achieved by drippers association of different flow rates in the same pipe. It was evaluated fresh and dry weight, number of leaves and diameter of lettuce plants (production variables); stomatal conductance, chlorophyll content, relative water content in leaves and chlorophyll fluorescence (physiological variables); and the water use efficiency (WUE). The corresponding volume 126% specified by the SIC installed to a tension soil of 6 kPa was that provided the best results production of dry weight, whereas the maximal WUE was obtained for the corresponding slide 80%. It indicates the volume of 83%, because it provided the best economy of water and a satisfactory production to sale. In the second chapter aimed to evaluate the use of the SIC under four different tensions to the substrate for the production of lettuce seedlings in trays under greenhouse conditions. It was evaluated fresh and dry weight of shoots, number of leaves, shoot height, leaf length and leaf area (production variables); chlorophyll content (physiological variable); and WUE. Higher water stress in the substrate decreased irrigation events, harming the growth of linearly seedlings and causing large percentage of deaths. The tension of 4 kPa was the one that provided the highest values in all production variables. The tension of 6.5 kPa despite having a percentage of death, can be used to produce more resistant seedlings / A preocupa??o com o uso intensivo dos recursos naturais tem se tornado cada vez maior, justificando o desenvolvimento de novas tecnologias que buscam sua aplica??o racional, como dispositivos autom?ticos de irriga??o. A automa??o da irriga??o pode permitir a economia da ?gua aumentando a efici?ncia de seu uso na produ??o agr?cola. O primeiro cap?tulo desse estudo teve como objetivo avaliar cinco diferentes volumes de irriga??o (130, 100, 80, 60 e 33% do volume do Acionador Simplificado de Irriga??o - ASI) na produ??o de alface em vasos em um sistema de produ??o denominado ?Vasoponia Org?nica?. Foi utilizado o ASI, cujo funcionamento baseia-se na tens?o da solu??o do solo. Os diferentes volumes foram conseguidos pela associa??o de gotejadores de vaz?es distintas em uma mesma tubula??o. Foram avaliados pesos fresco e seco, n?mero de folhas e di?metro das plantas de alface (vari?veis de produ??o); condut?ncia estom?tica, Teor de clorofila, conte?do relativo de ?gua nas folhas e fluoresc?ncia da clorofila (vari?veis fisiol?gicas); al?m da efici?ncia de uso da ?gua (EUA). O volume correspondente a 126% do indicado pelo ASI, instalado para tens?o de 6 kPa no solo, foi a que proporcionou os melhores resultados de produ??o de massa seca, enquanto que a m?xima EUA foi obtido para a l?mina correspondente a 83%. Indica-se o volume de 83%, pois proporcionou a melhor economia de ?gua e uma produ??o satisfat?ria ? comercializa??o. No segundo cap?tulo, objetivou-se avaliar a utiliza??o do ASI sob quatro diferentes tens?es no substrato para a produ??o de mudas de alface em bandejas de isopor em ambiente protegido. Foram avaliados peso fresco e da parte a?rea, n?mero de folhas, altura da parte a?rea, comprimento de folhas e ?rea foliar (vari?veis de produ??o); teor de clorofila (vari?vel fisiol?gica); al?m da EUA. Maiores tens?es de ?gua no substrato diminu?ram o n?mero de eventos de irriga??o, prejudicando o crescimento das mudas de forma linear e ocasionando grande percentual de mortes. A tens?o de 4 kPa foi a que proporcionou os maiores valores em todas as vari?veis de produ??o. A tens?o de 6,5 kPa apesar de apresentar um percentual de morte, pode ser utilizada para a produ??o de mudas mais resistentes.
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Tratamento eletrolítico de efluentes têxteis : avaliação da eficiência do processo e do potencial ecotoxicológico utilizando diferentes bioindicadores /

Moraes Júnior, José Rubens. January 2019 (has links)
Orientador: Ederio Dino Bidoia / Resumo: Os efluentes têxteis têm capacidade de proporcionar cor à água de rios e lagos devido aos corantes presentes em sua composição. Além dos problemas estéticos, outros compostos presentes nestes tipos de efluentes podem ser tóxicos à vida aquática. Os processos oxidativos avançados (POA) vem sendo estudados devido a vantagem de serem mais rápidos, produzirem menos resíduos e não demandarem de grandes áreas de instalação quando se comparado a tratamentos convencionais. Este trabalho teve como objetivo a degradação de efluentes simulados contendo o corante Acid blue 40, o corante Acid red 151 e efluente misto contendo ambos os corantes por tratamento eletrolítico utilizando eletrodo de titânio recoberto por titânio/rutênio (70%TiO2/30%RuO2) com área de 40 cm² em um sistema de recirculação. Foi realizado planejamento experimental e por meio de análise de superfície de resposta, configurações de tratamentos otimizados foram realizadas. Foram realizadas análises de espectrofotometria, DQO, DBO, Cor, pH, cloro residual livre e condutividade durante os processos de tratamento. Análise de espectro de infravermelho com transformada de Fourier (FTIR) foi realizada de todos os tratamentos. Foi também verificada a geração de clorofórmio por meio de análise de cromatografia gasosa e espectrometria de massa (GC-MS). Testes de ecotoxicidade com sementes de alface (Lactuca sativa) e rúcula (Eruca sativa) e com o microcrustáceo Artemia salina foram realizados durante os tratamentos. Teste de mut... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The textile effluents have the capacity to provide color to water from rivers and lakes due to the dyes present in their composition. In addition to aesthetic problems, other compounds present in these types of effluents can be toxic to the aquatic life. The advanced oxidative processes (AOP) have been studied due to the advantage of being faster, producing less waste and not having to spend large areas of installation when compared to conventional treatments. This work aimed at the degradation of simulated textile effluents containing the Acid blue 40 dye, Acid red 151 dye and a mixed effluent containing both dyes by electrolytic treatment using a titanium electrode covered by titanium/ruthenium (70%TiO2/30%RuO2) with an area of 40 cm² in a recirculating system. Experimental design was realized by the response surface the optimized configurations of the treatments were performed. Analysis of spectrophotometry, COD, BOD, color, pH, free residual chlorine and conductivity were performed during the treatment processes. Fourier transformed infrared spectrum analysis (FTIR) were performed in all treatments. The generation of chloroform was investigated by analysis of gas chromatography and mass spectrometry (GC-MS). Ecotoxicity tests with seeds of lettuce (Lactuca sativa) and arugula (Eruca sativa) and with the microcrustacean Artemia salina were performed for during treatments. Mutagenicity test was performed using the D7 strain of the yeast Saccharomyces cerevisiae. The optimiz... (Complete abstract click electronic access below) / Doutor

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