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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.
41

Intensification de l'agriculture biologique : conséquences sur la régulation des phytophages en vergers de pommiers / Intensification of organic farming : impact on the regulation of phytophagous in apple orchards

Marliac, Gaëlle 20 November 2014 (has links)
L’agriculture biologique (AB) est classiquement comparée à l’agriculture conventionnelle. Elle est alors souvent considérée comme plus favorable à la biodiversité que l’agriculture conventionnelle, même si certaines études montrent un effet négatif ou une absence d’effet de l’AB par rapport à l’agriculture conventionnelle pour certains taxons(Bengtsson et al. 2005; Garratt et al. 2011; Hole et al. 2005; Winqvist et al. 2011). Cela peut s’expliquer par le fait que l’AB ne se différencie pas seulement par le remplacement des produits phytosanitaires de synthèse par des produits autorisés en agriculture biologique mais aussi par la mise en œuvre d’autres pratiques comme l’implantation d’un couvert végétal.L’AB dispose d’une large gamme de pratiques visant à limiter les ravageurs et/ou à favoriser leur contrôle biologique via leurs ennemis naturels. Les objectifs de cette thèse sont :(i) d’établir un état des lieux de la diversité des stratégies de protection mises en place parles producteurs en AB pour lutter contre les deux ravageurs majeurs en vergers de pommiers,le carpocapse des pommes et le puceron cendré et d’identifier les pratiques permettant une diminution de l’usage des pesticides ;(ii) d’évaluer si ces pratiques ont un effet sur les communautés des prédateurs généralistes présentes dans la couronne ;(iii) d’estimer le rôle fonctionnel des prédateurs généralistes en mesurant la fonction de prédation en vergers de pommiers. En prenant comme cas d’étude les vergers de pommiers du Sud-Est de la France, nous avons dans un premier temps réalisé un état des lieux de la diversité des pratiques de protection mises en place en agriculture biologique à l’échelle de l’exploitation. Suite à une série d’enquêtes chez les producteurs, quatre stratégies de protection avec différentes combinaisons de pratiques ont été définies. Un suivi des ennemis naturels dans des parcelles types a permis de mettre en évidence des communautés d’ennemis naturels différentes selon les stratégies de protection.Dans un deuxième temps, nous avons étudié le lien entre la diversité des prédateurs généralistes et la régulation biologique (ici, la prédation des œufs de carpocapse). Cette étude a été réalisée sur 20 parcelles en AB caractérisées par différents usages de pesticides biologiques. Cette étude a permis de mettre en évidence des taux de prédation différents et une variabilité des communautés d’ennemis naturels selon les parcelles et d’identifier les ennemis naturels corrélés à la prédation des œufs. Dans un troisième temps, notre étude s'est portée sur une modification particulière de l'habitat, l’enherbement de l’inter-rang, une pratique mise en place par les producteurs et facile à gérer, notamment via l'intensité de fauche. Nous avons voulu déterminer, à l’aide d’une approche expérimentale en verger, si cette modification était un levier efficace pour augmenter l'abondance et la diversité des ennemis naturels et donc la régulation, soit au niveau de la canopée (prédation des œufs de carpocapse) soit au niveau du sol (prédation des larves de carpocapse). La communauté d’ennemis naturels dans l’arbre est apparue peu impactée par la hauteur d’enherbement ; seul Forficula pubescens est plus abondant lorsque le couvert végétal est haut (1m20). La prédation des œufs est quant à elle plus forte, aux mois de juillet et août, lorsque le couvert végétal est ras (5cm). La prédation des larves n’est pas différente selon la hauteur du couvert végétal.Cette thèse a permis de mettre en évidence une diversité des stratégies de protection en vergers de pommiers en AB. Elle a montré une variabilité des communautés d’ennemis naturels au sein de l’AB. Elle illustre la complexité du lien entre pratiques agricoles, ennemis naturels et prédation des bioagresseurs. / Organic agriculture is assumed to achieve more sustainable practices by reducing the negativeenvironmental impacts of intensive agriculture, such as biodiversity decline. While positivelinks between organic agriculture and natural enemy abundance and/or diversity have oftenbeen reported, this was not always the case (little or no difference between the systems, orsometimes in favor of the conventional system) and it appears to be variable depending on thespecies considered (Bengtsson et al. 2005; Garratt et al. 2011; Hole et al. 2005; Winqvist et al.2011). The benefits to biodiversity from organic agriculture are likely to stem primarily fromprohibition of synthetic chemicals but also from the adoption of various other managementpractices (cultural practices, ground cover management, presence of hedgerows). Indeed,organic management strategies are thus defined by a combination of different practices(Zehnder et al. 2007) that can have a different effect on the natural enemy community (Hole etal. 2005; Simon et al. 2007).The objectifs of this thesis are :(i) caracterized the diversity of crop protection strategies on organic agriculture andidentifed the practices led to reduced pesticide usage;(ii) investigated whether these practices have an impact on the natural enemy abundanceand diversity in the canopy;(iii) assess the natural enemy predation activity in apple orchard.First, we identified four crop protection strategies, which were characterized by aspecific combination of different types of practices. We showed that natural enemycommunities and their efficacy were influenced by these strategies.Second, we examined the relationships between the abundance of generalist predatorsand the level of pest control under natural conditions (predation of codling moth eggs). Weused a set of organically farmed commercial orchards with various protection strategies andshowed that the predation rate and the natural enemy communities were different but variableamong the organic apple orchard. We identified the natural enemy correlated with thepredation rate.!Finally, we managed the ground cover and compared the effect of three heights, tall(no cutting), medium (mean height of 20 cm) and short (mean height of 5 cm), of aspontaneous grass cover in an experimental orchard on natural enemy abundance andpredation rates on the canopy (predation of codling moth egg) and on the ground (predation ofcodling moth larvae). The natural enemy community on the canopy was little impact by theheight of the ground cover ; only Forficula pubescens was more abundant in the no cuttingthan in the short ground cover. The egg predation was higher in the short ground cover than inthe two other modalities. The larvae predation was not impacted by the ground cover height.We caracterized a diversity of crop protection strategy on organic agriculture in appleorchard. We identified a variability of the natural enemy communyties on organic appleorchard. This thesis illustrated the complexity of the relationship between agriculturalpractices, natural enemies and predation of pests.
42

EVALUATING THE EFFECTS OF ORGANIC AND CONVENTIONAL INPUTS ON SOIL CHEMICAL AND BIOLOGICAL PROPERTIES IN A FOUR-YEAR VEGETABLE ROTATION AND THE INVESTIGATION OF SOIL MICROBIAL PROPERTIES ON PLANT GENE EXPRESSION

Law, Audrey 01 January 2009 (has links)
The objective of this research was to determine the effects of conventional inputs on soil chemical and biological properties compared to organic systems in a four year vegetable rotation. Tillage and cover crops were the same in all treatments to avoid confounding factors often present in similar research. Additional experiments investigated plant gene expression in organic and conventional management systems and in soils with decreased microbial diversity. Experimental plots were prepared in the spring of 2004; four replications of three management treatments, organic, low-input and conventional, were arranged in a randomized complete block design. The rotation consisted of edamame soybean, sweet corn, fallow (pastured poultry in organic plots), and potatoes. Soil samples were taken in the spring and fall of each year, along with data for pest damage, weed control, yield and quality. Soil samples were analyzed for enzyme activity (maximum activity under substrate saturation) and basic soil chemical properties. Treatments were compared over time using 2-Way ANOVA. Multiplex terminal-restriction fragment length polymorphism (M-TRFLP) profiles of the soil microbial community were compared using Multiple Response Permutation Procedures (MRPP). Multi-way ANOVA detected significant treatment effects over time in total carbon, nitrogen, Mehlich III K, Exchangeable K and exchangeable Na (p=0.05). Many significant changes in soil properties over time could not be attributed to treatment effects. All treatments produced similar yields, indicating that successful organic production of these vegetables is possible in Kentucky. Input costs for organic were 37% higher than conventional, due to the cost of organic fertilizer. The organic system required nearly 50% more labor hours than conventional or low-input. The low-input system was the most cost effective, with 58% less input expenses than the conventional system. Microarray analysis of approximately 37,500 Glycine max transcripts did not show significant differences in the gene expression between plants grown organically and conventionally, in plots with significant soil chemical and microbial differences. An experiment in progress is investigating changes in plant gene expression using real time RT-PCR in tomatoes grown in autoclaved soil and native field soil.
43

An investigation into ecological farming systems on the Canadian Prairies

Dick, Calvin 13 September 2016 (has links)
There are currently numerous alternative food production models that may have potential to contribute substantially to improved environmental sustainability. However, such alternatives are not well studied, particularly within the context of the Canadian Prairies. To increase knowledge in this area, this thesis performed a preliminary agronomic trial for food grain production in intermediate wheatgrass (Thinopyrum intermedium), investigating the effects of legume intercropping and residue management. Mean grain yields were 520 and 447 kg/ha in 2014 and 2015, respectively, and a significant yield increase was observed following grazing with sheep. A series of farm case studies were also conducted in order to characterize ecological farming approaches on the Canadian prairies. The most consistent strategy among the farms was to increase diversity in multiple facets for both environmental and economic benefit, including more crop and livestock species, system and landscape components, and marketing strategies. / October 2016
44

Problematika biopotravin v ČR / The problems of the organic food in the Czech Republic

Bořkovcová, Eva January 2010 (has links)
The theoretical part of this diploma thesis deals with the history of organic agriculture, organic agriculture in the world, in Europe and in the Czech Republic. In terms of the Czech Republic, it focuses on the development and the current state of organic agriculture, legislative background, supervision and certification, state subsidy and the labelling of organic food. The last chapter of the theoretical part answers questions: Why should people buy organic food, and why should they prefer local organic food to the imported one? It is also concerned with the distribution of organic food. In the practical part the main problems in terms of securing the sale of organic food in the Czech Republic are detected by the means of questionnaire examination. Two types of questionnaires were created for the purpose of the research. The first type is for organic producers and the second one for the sellers of organic food and healthy food products. At the end of this diploma thesis there is a summary of the recognized problems and the forshadowing of the future of organic agriculture in the Czech Republic.
45

Customer Perceptions of Organic Certification Standards

Kokic, Damir, Pedersen-Slaatten, Marcus Brando January 2019 (has links)
Along with the organic food market development, two directions within the industry has appeared, the traditional organic farming and the biodynamic organic farming. The thesis aimed to derive at which organic certification of organic food in the Swedish food market is most appropriate to the organic movement, based on customer perceptions of Swedish University students. The thesis looked at KRAV, a certifier of traditional organic farming, and Demeter, a certifier of biodynamic organic farming. A quantitative method was used to gain a deeper understanding of the consumer perceptions of organic certification standards and the comparison of KRAV and Demeter, and which certification consumers preferred. A survey was distributed in order to find out the consumer perceptions. The findings of the thesis were split into two parts, each answering one research question. The first part showed that people adhered to the standards of Demeter, with average means skewed towards their side of the scale. The second part identified five hypotheses to be tested against each other, and found customer confusion to be the main impacting factor of consumer perceptions of organic food standards.
46

Planejamento da conversão do café convencional para o orgânico: um estudo de caso / Planning the conversion from conventional to organic coffee: a case study

Oliveira, Renato Alves de 11 April 2012 (has links)
A Agricultura Orgânica oferece, ao mercado consumidor, produtos isentos de agentes químicos. Os produtores que fazem uso do sistema convencional e estiverem interessados em adotar a tecnologia orgânica de produção deverão se credenciar junto ao Ministério da Agricultura através de uma certificadora de produtos orgânicos. A certificação pode ser por auditoria ou participativa, mas para recebê-la o agropecuarista deve seguir as normas e procedimentos estabelecidos pela legislação brasileira de produtos orgânicos. Um dos procedimentos é o processo de conversão ou transição, pelo qual a atividade agrícola em manejo convencional muda para o manejo orgânico. O tempo de transição pode variar de 12 a 18 meses, no mínimo, de acordo com a espécie vegetal ou animal e pelo histórico da unidade produtiva. No caso do café, a conversão do sistema convencional para o orgânico pode trazer consigo, entre outros benefícios, a independência de insumos externos, menor risco para a saúde e pode proporcionar maior lucro ao produtor. Esta pesquisa tem como objetivo desenvolver um planejamento de produção do café para o processo de conversão da técnica convencional para a orgânica no Sítio Terra Verde em Espírito Santo do Pinhal no estado de São Paulo. Utilizou-se a metodologia de programação linear para maximizar o lucro e minimizar o custo de produção do café em seis cenários. O plano de conversão foi de oito anos, respeitando a bienalidade do cafeeiro, passando por três fases de manejo: substituição de insumos, conversão e produção orgânica. Foram realizadas três análises sobre o planejamento de conversão. Os resultados da primeira análise mostraram que a adoção da técnica orgânica proporcionou ao cafeicultor lucros superiores aos do sistema convencional no final do período de conversão, quando ocorre aumento sobre o preço da saca. Os cenários da segunda análise identificaram uma situação de prejuízo ao cafeicultor no 4º ano do planejamento e uma condição econômica desvantajosa em relação ao sistema convencional, pois o lucro geral foi inferior, devido à redução da produtividade até o final da conversão. A terceira análise apresentou uma situação em que o produtor não recebe o incremento sobre o preço da saca de café quando em manejo orgânico, o que levou à obtenção de resultado desvantajoso ao produtor, no qual o lucro geral do sistema orgânico foi muito baixo em relação ao do sistema convencional. Conclui-se que especificamente para o Sítio Terra Verde, pode ser economicamente viável a adoção da produção orgânica na cultura do café, mas é com extrema dependência do diferencial do preço entre os sistemas convencional e orgânico. / Organic agriculture offers products to the consumer market free of chemicals. Producers who use the conventional system and are interested in adopting organic production technology must be certified by the Ministry of Agriculture through a certification of organic products. Certification may be obtained by auditing or participatory, but in order to receive it, the rural producers must follow the rules and procedures established by the Brazilian laws for organic products. One example is the process of conversion or transition, through which the agricultural activity is converted from conventional farming to the organic one. The transition time may vary from 12 to 18 months, at least, according to the vegetal or animal species and the farm history. In the case of coffee, the conversion from conventional to the organic system can bring some benefits, for example, the independence of external inputs, risk lower to health and can provide more profit to the producer. Thus, this research aims carry out a coffee a plan of partial conversion to organic production technology for a rural property called Sítio Terra Verde at Espírito Santo do Pinhal, São Paulo State, which uses the conventional system. It was used linear programming to maximize profit and minimize costs of coffee production in six scenarios. The conversion planning was established to occur in eight years, respecting the twice yearly harvesting, with three stages: input substitution, conversion and organic production. Were held three analysis on the conversion plan. The results of the first analysis showed that the adoption of organic technique provided greater profits for the producers than the conventional system at the end of the conversion period, when the coffee bag\'s price raises. The second analysis scenarios identified a prejudice situation for the producer in the 4th year of planning and a disadvantage economic condition compared to the conventional system, because the overall profit was lower due to the reduction in productivity by the end of conversion time. The third analysis showed a situation where the producer does not receive a higher price due to the organic management, with a disadvantageous result for the producer, since the overall profit of the organic system was much lower compared to the conventional system. It was concluded that specifically for Sítio Terra Verde the adoption of organic management for the coffee farming can be economically viable, but it is extremely dependent on price differential between conventional and organic systems.
47

Avaliação de cultivares de feijão (Phaseolus vulgaris L.) para o sistema orgânico de produção / Evaluation of cultivars of beans (Phaseolus vulgaris L.) to the organic management of production

Araujo, Jacqueline Camolese de 11 August 2008 (has links)
Com o objetivo de avaliar as características, as produções e os comportamentos das diferentes cultivares de feijão de inverno irrigado em sistema de produção orgânico, conduziu-se um experimento na área experimental pertencente à Escola Superior de Agricultura \"Luiz de Queiroz/Universidade de São Paulo, localizada na Fazenda Areão e no núcleo experimental do Grupo de Agricultura Orgânica Amaranthus. Os seguintes parâmetros foram avaliados: a produtividade, número de flores por planta, número de vagens por planta, número de grãos por vagem, o índice de área foliar bem como o teor de nutrientes para cada variedade. As variedades analisadas foram do Grupo Carioca: BRS-Pérola, BRS-Aporé, IAC- Votuporanga e IPR- Juriti, e do Grupo Preto: IAC-Tunã e BRS-Valente. De acordo com o que foi analisado, os resultados permitem concluir que: (i) não houve diferença estatística entre os tratamentos, (ii) todas as cultivares avaliadas apresentaram ótimo desempenho sob manejo orgânico. / The goals of this study were to evaluate the characteristics, productivities and behaviors of different cultivars of common bean in an irrigate organic management system in the winter. The experiment was carried out at the experimental area of the Group of Organic Agriculture Amaranthus from Escola Superior de Agricultura \"Luiz de Queiroz\"/University of São Paulo, in Fazenda Areão, in Piracicaba, São Paulo State, Brazil. The following agronomic parameters related to common bean crop were used for statistical analysis: grain yield, number of flowers per plant, number of pods per plant and grains per pod, leaf area index, as well as leaf nutrient content for each cultivar. It were tested the following varieties from Carioca Group: BRS-Pérola, BRS-Aporé, IACVotuporanga and IPR- Juriti, and from Black Group: IAC-Tunã and BRS-Valente. The results showed that: (i) there were no statistical differences between the treatments, (ii) all the tested varieties had great productivity under organic management system.
48

Do convencional ao orgânico: respostas de um manejo de transição em um pomar cítrico / From conventional to organic: responses of a transition management in a citrus orchard

Homma, Sergio Kenji 26 September 2017 (has links)
Os modelos orgânicos de produção despontam como uma alternativa à agricultura convencional, entretanto, a falta de conhecimento para o processo ainda é uma grande lacuna. O objetivo deste trabalho foi testar o efeito da adoção gradual de insumos e práticas agronômicas mais ecológicas, até a total substituição por procedimentos permitidos pelas normas da produção orgânica (TRANS) na cultura dos citros. A comparação foi feita em área equivalente e contígua onde o manejo convencional da propriedade foi mantido (CONV). O ensaio foi conduzido por 5 anos dentro de uma quadra de produção comercial de citros. Para o presente estudo foram avaliadas as três últimas safras, sendo 2013/2014, 2014/2015 e 2015/2016. As variáveis de solo foram analisadas em duas profundidades (00-20 e 20-50 cm) e foram avaliados dados de: microbiologia do solo (qPCR e T-RFLP de bactérias e fungos, CBMS, qCO2, qMIC, micorrìza e glomalina); física de solo (dados de Curva de Retenção e agregados estáveis) e; fertilidade do solo. Das variáveis de planta foram avaliadas: teor de nutrientes foliares, produtividade e índice \"ratio\" do suco. As comparações e as interações das variáveis no conjunto de respostas do ensaio foram analisadas pelo teste t de Student, Análise de Componentes Principais e Análises de Coordenadas Principais. O conjunto das variáveis de solo e planta mostraram melhores respostas no tratamento TRANS nas safras 13/14 e 14/15, convergindo com os melhores resultados de produtividade. Na safra 15/16 a resposta na nutrição das plantas, particularmente em N, Mn e Zn, não foram capazes de manter a produtividade nos mesmos patamares do CONV. A comunidade de bactérias e fungos do solo estruturaram-se de forma distinta na safra 13/14, em resposta ao manejo do tratamento TRANS e ao menor volume de chuva, e foram muito próximas nas safras 14/15 e 15/16, períodos mais chuvosos. Os dados trazem vários indicativos para subsidiar práticas agronômicas voltadas à transição para a citricultura orgânica e sustentável. / The organic agriculture systems appear as an alternative to conventional agriculture. However, the lack of knowledge to proceed the transition is still a big gap. The aim of this work was to test the effect of gradual adoption of ecological inputs and agronomic practices, up to total substitution for techniques allowed by organic agriculture rules (TRANS), in the citrus cultivation. The TRANS plots were compared with an equivalent and adjacent area, where the farmer conventional management was maintained (CONV). The experiment was carried out for five years inside a commercial orchard. For this work, the last three crops years were assessed: 2013/2014, 2014/2015 e 2015/2016. The variables were evaluated at two depths (00-20 and 20- 50 cm) and the following analysis were performed: soil microbiology (bacteria and fungi qPCR and T-RFLP, MBC, qCO2, qMIC, mycorrhizal fungi and glomalines); soil physics (data of water retention curve and stable aggregates); and soil fertility. From the plant variable: foliar nutrient content; fruits production and juice ratio index were evaluated. The results and interactions of the all variables were compared applying Student t test, Principal Components Analysis (PCA) and Principal Coordinates Analysis (PCoA). In general, the set of soil and plant variables shows the best responses in the TRANS plots, in the 13/14 and 14/15 crop years, and it matched with the best harvest results. In the 15/16 crop year, the plant nutrition responses, particularly N, Mn and Zn, was not capable to maintain the same levels of CONV plots fruits production. The structure of soil bacteria and fungi community shaped in different way, between treatments, in the 13/14 crop year, responding to the changes from TRANS and lower amount of rainfall. These structures were close to similar in the 14/15 and 15/16 crop years, when the amount of rainfall was higher. The data bring forward several indications to assist agronomical practices toward a transition to organic and sustainable citrus cropping.
49

Cultivares para o sistema orgânico de produção de batata / Potato Cultivars for Organic Production

Rossi, Fabrício 04 June 2009 (has links)
A crescente demanda por batata e outras hortaliças cultivadas organicamente no Brasil representa uma importante oportunidade e um desafio para os produtores orgânicos. Na atualidade, é limitado o esforço de pesquisa enfocando fertilização, adaptação de cultivares e manejo de pragas e doenças para sistemas orgânicos de cultivo da batata. Em geral, a produtividade na produção orgânica de batata é baixa em comparação a obtida no sistema convencional, devido à cultura estar sujeita à inúmeras pragas, doenças e distúrbios fisiológicos. Como não existem no mercado cultivares adaptadas especificamente ao sistema orgânico, os produtores utilizam cultivares européias e norte-americanas desenvolvidas para o sistema convencional de cultivo. O objetivo deste estudo foi avaliar, sob sistema de cultivo orgânico, cultivares nacionais e estrangeiras desenvolvidas para o cultivo convencional, quanto ao potencial produtivo e qualidade, em condições de campo, sujeitas ao ataque de pragas e doenças. Os experimentos foram conduzidos, em 2007 e 2008, em dois locais: a) Estação Experimental Agroecológica do Pólo Regional do Leste Paulista/APTA, em Monte Alegre do Sul - SP, b) Sítio Orgânico Pereiras, em Socorro - SP. O delineamento experimental adotado foi em blocos ao acaso com quatro repetições. Os tratamentos constaram das cultivares Agata, Apuã (IAC-5977), Aracy (IAC-2), Asterix, Caesar, Catucha (Epagri-361), Cupido, Éden, IAC Aracy Ruiva, Itararé (IAC-5986), Melody, Monte Alegre 172, Novella e Vivaldi, além dos clones avançados IAC 6090 (Ibituaçú), APTA 16.5, APTA 15.20 e APTA 21.54. Em cada experimento foram incluídas, pelo menos, 10 cultivares. As demais cultivares e clones avançados foram incluídos, pelo menos, em um experimento. Foram avaliados os seguintes parâmetros: produtividade total e comercial, números total e comercial de tubérculos, teor de matéria seca, açúcares redutores e totais, resistência à requeima (Phytophthora infestans) e à pintapreta (Alternaria solani). Em 2007, em Monte Alegre do Sul, as cultivares Apuã (14,32 t ha-1), Monte Alegre 172 (13,44 t ha-1), e o clone Ibituaçú (12,75 t ha-1) apresentaram os rendimentos mais elevados. No mesmo ano, em Socorro, Ibituaçú (21,27 t ha-1) apresentou o maior rendimento entre os genótipos avaliados. Em 2008, em Monte Alegre do Sul, os clones APTA 16.5 (24,25 t ha-1), APTA 21.54 (23,21 t ha-1) e Ibituaçú (20,19 t ha-1), e as cultivares Cupido (18,03 t ha-1), Apuã (17,08 t ha-1), Itararé (16,66 t ha-1), e Monte Alegre 172 (16,18 t ha-1) mostraram as maiores produtividades. No mesmo ano, em Socorro, APTA 16.5 (21,02 t ha-1), APTA 21.54 (19,28 t ha-1), Ibituaçú (19,88 t ha-1), e Apuã (18,72 t ha-1) mostraram excelente desempenho para rendimento. Os teores de matéria seca e de açúcares redutores para todos os genótipos avaliados mostraram, respectivamente, valores maiores e menores em relação aos encontrados na literatura. APTA 16.5, Apuã, Aracy, Aracy Ruiva, Éden, Ibituaçú e Monte Alegre 172 apresentaram de moderado a elevado nível de tolerância à pinta-preta, apresentando poucos ou ausência de sintomas da doença. Apuã, Aracy, Catucha, Ibituaçú e Monte Alegre 172 mostraram elevado nível de resistência à requeima. / An increasing demand for organic potato and other vegetable crops in Brazil represent a considerable opportunity and a challenge for organic growers. So far, limited research has been conducted on organic potato production in Brazil pertaining to fertilization, cultivar adaptation, and pest management for organic potato systems. Yields in organic potato production are usually lower than in conventional production systems, because the crop is subject to many pests and physiological disorders. Furthermore, potato cultivars adapted to organic systems are unavailable in the market. Thus, European and North American cultivars developed for conventional crops that have high yielding potential and tolerance to the most limiting diseases and physiological disorders are used by the organic growers. The aim of this study was to evaluate under organic production on-farming conditions, potato cultivars bred in Brazil and abroad adapted for conventional growing systems, in terms of yield potential and qualities. The experiments were conducted in 2007 and 2008, in two locations: a) Agro-ecological Experimental Station of the Polo Regional do Leste Paulista/APTA, in Monte Alegre do Sul - SP County; b) Pereiras agro-ecological farm, Socorro-SP County. A randomized block experimental design was adopted with four replicates. The treatments consisted of the cultivars Agata, Apuã (IAC-5977), Aracy (IAC-2), Asterix, Caesar, Catucha (Epagri- 361), Cupido, Éden, IAC Aracy Ruiva, Itararé (IAC-5986), Melody, Monte Alegre 172, Novella, and Vivaldi, in addition to the advanced clones IAC 6090 (Ibituaçú), APTA 16.5, APTA 15.20 and APTA 21.54. In each experiment there were trialed at least 10 cultivars. The other cultivars or advanced clones were included at least in one experiment. The following parameters were evaluated: total and commercial yield, total and commercial number of tubers, dry matter content, reducing and total sugars, severity of potato late blight (Phytophthora infestans) and early blight (Alternaria solani). In 2007, in Monte Alegre do Sul, the cultivars Apuã (14.32 t ha-1), Monte Alegre, 172 (13.44 t ha-1), and Ibituaçú (12.75 t ha-1) displayed the highest yield performance. In the same year, in Socorro, Ibituaçú (21.27 t ha-1) exhibited the highest yield among trialed cultivars. In 2008, in Monte Alegre do Sul the advanced clones APTA 16.5 (24.25 t ha-1), APTA 21.54 (23.21 t ha-1), Ibituaçú (20.19 t ha-1), and cultivars Cupido (18.03 t ha-1), Apuã (17.08 t ha-1), Itararé (16.66 t ha-1), and Monte Alegre 172 (16.18 t ha-1) showed high yielding performance. In the same year, in Socorro, the treatments APTA 16.5 (21.02 t ha-1), APTA 21.54 (19.28 t ha-1), Ibituaçú (19.88 t ha-1), and Apuã (18.72 t ha-1) showed outstanding yield performance. The dry matter and reducing sugars in all genotypes showed higher and lower, respectively, in relation to those found in the literature. APTA 16.5, Apuã, Aracy, Aracy Ruiva, Éden, Ibituaçú and Monte Alegre 172 exhibited moderate to high level of field tolerance to early blight, displaying few or absence of the disease symptoms. ´Apuã, Aracy, Catucha, Ibituaçú and Monte Alegre 172 showed the highest level of resistance to late blight.
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Avaliação do tratamento alopático e homeopático de mastite bovina em animais inoculados com Staphylococcus aureus / Evaluation of allopathic and homeopathic treatments of bovine mastitis in inoculated animals with Staphylococcus aureus

Almeida, Leslie Avila do Brasil 26 October 2004 (has links)
A mastite bovina é considerada a doença que causa os maiores prejuízos à produção leiteira, reduzindo em quantidade e qualidade o leite e os derivados lácteos. Especialmente na mastite clínica, ocorre aumento no risco de resíduos de antimicrobianos no leite, portanto além do prejuízo diretamente relacionado ao processo inflamatório, acrescenta-se o custo com medicamentos, aumento do labor da mão-de-obra e tempo de descarte do leite após tratamento, até a total eliminação os resíduos de antibióticos utilizados. A expansão dos sistemas de produção pecuária orgânica aumenta a necessidade de utilizar métodos diferentes daqueles conhecidos convencionalmente.A homeopatia é uma terapêutica que tem sido cada vez mais utilizada em animais de produção com resultados bastante satisfatórios. No Brasil a produção orgânica é regulamentada pela Lei No10.831 de 23 de dezembro de 2003 e lá há orientação para o uso de medicamentos homeopáticos, assim como fitoterapia e acupuntura na terapêutica animal, em lugar dos medicamentos convencionais, que têm seu uso muito restrito e em certos casos proibido. Para realização deste trabalho foi feita uma inoculação intramamária experimental com estirpes de Staphylococcus aureus em 36 quartos mamários de 18 vacas mestiças de Holandesas e Gir pertencentes ao Campo Experimental de Coronel Pacheco/MG da Embrapa/CNPGL, com o objetivo de comparar o tratamento de animais acometidos com a utilização de medicamentos homeopáticos (Phytolacca decandra 6CH, Calcarea carbonica 6CH e Silicea terra 6CH) e com antibiótico (Cefoperazone Sódico), usando como parâmetros para este estudo: os sinais clínicos, a prova de CMT, as contagens de células somáticas , tanto eletrônicas quanto ópticas e culturas microbiológicas, além da avaliação do custo dos dois tratamentos. No presente estudo não houve diferença estatisticamente significante quanto à intensidade do processo inflamatório avaliados pelo CMT e contagens de células somáticas, quanto ao número de unidades formadoras de colônias isoladas do leite das glândulas mamárias inoculadas e entre período de convalescença dos dois tratamentos. O custo de aquisição dos medicamentos para o tratamento de mastite aguda utilizando homeopatia foi muito inferior ao mesmo tratamento realizado com antibiótico intramamário / The bovine mastitis is considered the illness that causes most losses in milk production, reducing the quantity and quality of milk and dairy products. Especially in clinical mastitis there is an increase on the risk of antimicrobials in milk. Therefore, beyond the losses directly related with the inflammatory process, there is also the expense with drugs, an increase in the animal handling and a discard of milk after the antibiotics treatment, up until the totally elimination of the drug residues. The expansion of organic animal production systems increases the necessity of using different methods of those already conventionally known. Homeopathy is a therapeutically method that has been more used in livestock with satisfactory results. In Brazil, organic production is regulated by the law number 10.831 of December 23rd of 2003, where there is an orientation for using homeopathic medicines as well as phytotherapy and acupuncture in animal health instead of conventional medicines which are restricted in many cases and sometimes even forbidden. In order to develop this research it was done an experimentally intramammary inoculation with a strain of Staphylococcus aureus in 36 mammary gland quarters of 18 cows cross-bred with Holstein and Gir from the Experimental Fields of Coronel Pacheco/MG of Embrapa/CNPGL. The purpose was to compare the treatment of the inoculated animals with homeopathy (Phytolacca decandra 6CH, Calcarea carbonica 6CH and Silicea terra 6CH) and antibiotic (Sodic Cefoperazone). The parameter used for this study were clinical signs, CMT, counting of somatic cells electronically in as much as using the optical method and microbiological cultures. It was also estimated the costs of both treatments. At the present study there was no statistical difference in intensity of the inflammatory process evaluated by the CMT and somatic cell counts, by the number of CFU isolated from milk of the inoculated mammary glands and between the times of convalescence in both treatments. The cost of acquisition of medicines for the treatment of acute mastitis using homeopathy was very lower when compared with the same treatment done with intramammary antibiotics

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