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

Pflanzenschutzempfehlung Zierpflanzenbau

January 2008 (has links)
Die aktuelle Ausgabe der Broschüre gibt anwendungsorientierte Informationen zum Pflanzenschutz. Sie beinhaltet Empfehlungen sowohl zu chemischen als auch biologischen Bekämpfungsmöglichkeiten. Es werden wesentliche Rechtsgrundlagen der Pflanzenschutzmittelanwendung genannt sowie Hinweise zur Kontrolle und Reinigung von Pflanzenschutzgeräten gegeben.
22

Target region amplification polymorphism (TRAP) analysis of <i>Pelargonium</i>

Palumbo, Rose E. 07 January 2008 (has links)
No description available.
23

Caracterização de helicônias para o paisagismo / Heliconia characterization for from landscape design

PINHEIRO, Paula Guimarães Lago 21 July 2010 (has links)
Submitted by (ana.araujo@ufrpe.br) on 2017-02-21T13:38:47Z No. of bitstreams: 1 Paula Guimaraes Lago Pinheiro.pdf: 1345137 bytes, checksum: dd311733f8b60dbc79fa8fc2930d2a15 (MD5) / Made available in DSpace on 2017-02-21T13:38:47Z (GMT). No. of bitstreams: 1 Paula Guimaraes Lago Pinheiro.pdf: 1345137 bytes, checksum: dd311733f8b60dbc79fa8fc2930d2a15 (MD5) Previous issue date: 2010-07-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Recently the use of heliconia as cut flowers, stimulated the interest of the use of new species in landscaping. Those plants offer beauty and exoticism to the garden and follows the tendency of landscape projects with native plants. The Heliconia genus, Heliconiaceae family, have plants with exotic inflorescences in vibrant colors that range for yellow, orange, red, and pink that are characterizes as tropical gardens plants. There are around 182 species of Heliconia, nevertheless, due to the lack of knowledge on the individual characteristics of the species from this genus, only a few are used as ornamental plants by landscape professionals. This work was carried out to evaluate ornamental characteristics of genotypes from Heliconia, grown in full sun in the period January to December 2008, as well as involve them in landscape applications. The experiment was conducted at Heliconias Germoplasm Collection of Federal Rural University of Pernambuco (UFRPE), through analysis for the qualitative and quantitative characteristics related to clump and inflorescences aspect of this genotypes. Except for cv. Red Opal, H. psittacorum cultivars and its interspecific hybrids were considered to be short plants (less than 1.51 meters height) and adequate as a massive flower bed that would not interfere on the views and may be used to complement design lines, generating ambiences and ordering the garden spaces. The genotypes H. collinsiana, H. rostrata and H. foreroi showed inflorescences which last longer than 78 days in good conditions in the clump, which is an remarkable aspect in the landscape. H. bihai inflorescences was difficult to visualize, its bracts accumulate water, attract insects and have odor. An experiment conduct from January 2007 to July 2008 permitted evaluated Heliconia x nickeriensis to ornamental characteristics and management for garden use. It’s described as short height plant, with quick development, dispersed type of clump architecture and open growth habit. The clump area reached 5.14 m2 at 18 months after planting (MAP), demonstrading the necessity of a large space for development . The shoots emission in the internal part of the clump permitted a complete soil coverage. The dark green leaves contrast with the yellow-orange inflorescence which are easily visualized above its foliage. The flowering period started at 9 MAP, reaching an emission of more than 17 inflorescences per clumb at 17 MAP. The inflorescences kept the quality for more than 25 days after its emittion in the clump. This genotype represents a good option to be used either isolated, for covering large open areas, or grouped with other ornamental plants to create compositions with different colors, forms and textures. This heliconias have particularities that confer acceptation and adequacy to landscape design, allowing the landscape professionals to diversify plant specifications. / Recentemente o uso das helicônias como flores de corte, despertou o interesse da utilização de novas espécies no paisagismo que, além de oferecer beleza e exotismo ao jardim, segue a tendência atual de projetos paisagísticos com plantas nativas. O gênero Heliconia, pertencente à família Heliconiaceae, apresenta inflorescências com cores vibrantes, que variam entre as cores amarelo, laranja, vermelho e rosa, conferindo exoticidade e caracterizando-as como plantas de jardins tropicais. Embora existam cerca de 182 espécies de helicônias, poucas são utilizadas como plantas ornamentais e indicadas por profissionais da área de arquitetura e paisagismo. Isso acontece devido ao reduzido conhecimento das características individuais das espécies. Este trabalho foi conduzido com o objetivo de avaliar características ornamentais de genótipos do gênero Heliconia, cultivados a pleno sol, no período de janeiro a dezembro de 2008, como também associá-las a aplicações paisagísticas. O experimento foi desenvolvido na Coleção de Germoplasma de Helicônias da Universidade Federal Rural de Pernambuco (UFRPE), através de estudos das características qualitativas e quantitativas relacionadas a touceiras e inflorescências dos genótipos. Com exceção cv. Red Opol, as cultivares e os híbridos interespecíficos de Heliconia psittacorum apresentaram pequeno porte (altura inferior a 1,51 metros) e por isso podem ser utilizadas em maciços. As inflorescências de H. collinsiana, H. rostrata e H. foreroi permaneceram na touceira por mais de 78 dias, mantendo o conjunto florido por longo período, característica importante para o paisagismo. A espécie H. bihai apresentou difícil visualização das inflorescências, acúmulo de água nas brácteas, atração a insetos e odor desagradável. O Experimento conduzido em janeiro de 2007 a julho de 2008 permitiu o acompanhamento mais detalhado da Heliconia x nickeriensis. As touceiras deste genótipo foram consideradas de pequeno porte, com desenvolvimento rápido e hábito de crescimento aberto. A área de ocupação da touceira chegou 5,14 m2, 18 meses após o plantio (MAP), evidenciando a necessidade de um grande espaço para o desenvolvimento desta. A emissão de perfilhos na parte interna da touceira permitiu uma completa cobertura do solo. As folhas verde-escuras contrastam com as inflorescências amarelo-laranja, que são facilmente visualizadas acima de sua folhagem. O período de floração começou 9 (MAP), atingindo uma emissão de mais de 17 inflorescências por touceira por mês, até os 17 MAP. As inflorescências mantiveram a qualidade nas touceiras por mais de 25 dias após a emissão. Este genótipo representa uma boa opção para uso isolado, para cobertura de grandes áreas, ou agrupados com outras plantas ornamentais para criação de composições com diferentes cores, formas e texturas. Estas helicônias apresentaram particularidades que lhes permitem o uso no paisagismo, de modo diversificado a partir de suas diferentes formas, portes e cores nos projetos paisagísticos.
24

Sazonalidade, refrigeração e diferentes tipos de recobrimento na conservação pós-colheita de estacas de cordiline (Cordyline rubra Hügel). / Seasonality, refrigeration and different types of coating on the postharvest conservation of Cordyline rubra Hügel cuttings.

Sakamoto, Nelson Mamoru 06 June 2005 (has links)
O mercado mundial de floricultura gera um fluxo de quase US$ 7bilhões anuais, atualmente concentrado em países como Holanda, Alemanha, Itália, Colômbia, Costa Rica, Equador, Quênia, Tailândia, Malásia, Israel e EUA. O Brasil ainda contribui pouco, aproximadamente 0,3% do total, sendo a participação brasileira concentrada na exportação de mudas, bulbos, flores e folhagens tropicais. O Brasil possui grande potencial exportador de flores e plantas ornamentais através da organização dos produtores, profissionalização do setor, apoio governamental e desenvolvimento técnico. O emprego de técnicas simples de armazenamento poderia viabilizar o transporte por modais que não o aéreo, reduzindo custos e podendo prolongar a vida útil dos produtos, criando um diferencial de qualidade em relação aos concorrentes. Este trabalho compara cinco diferentes tipos de recobrimento em estacas de Cordyline rubra Hügel (película amilácea, pasta de parafina no ápice, pasta de parafina no ápice e vermiculita umedecida na base, saco plástico ou sem recobrimento), sazonalidade (estacas coletadas durante primavera ou outono), dois ambientes de armazenamento (ambiente refrigerado a 10ºC ou temperatura ambiente 22-32ºC) e diferentes períodos de armazenamento (30, 60, 90 ou 120 dias), a fim de reduzir sua atividade biológica, perda de água e ataque de patógenos. Foi escolhida esta espécie por ser muito apreciada como planta ornamental devido à beleza de suas folhas, e exportada na forma de estacas de diferentes tamanhos. O experimento foi conduzido nas dependências do Departamento de Produção Vegetal da Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, no município de Piracicaba, Estado de São Paulo. Foram utilizadas 615 estacas com 30 cm de comprimento por 3 cm de diâmetro. Um lote testemunha sem armazenamento de 15 estacas foi colocado em leito de enraizamento. Cada tratamento foi composto por 30 estacas pré-tratadas (tipos de recobrimento), submetidas a diferentes períodos de armazenamento (30, 60, 90 ou 120 dias), sendo divididos em 2 sub-tratamentos de 15 estacas (temperatura ambiente ou refrigerada), totalizando 120 estacas. Após o armazenamento foram cortados 3 cm da base de cada estaca, em seguida tratadas com IBA a 10.000 mg/L e colocadas em leito de enraizamento. Após 90 dias foram avaliados os seguintes parâmetros: porcentagem de desenvolvimento, número e massas de matéria fresca e seca de brotos, raízes e rizomas. Observou-se que as estacas colhidas na primavera apresentaram melhor enraizamento e produção de massas secas e frescas. Os menores períodos de armazenamento proporcionam melhor desenvolvimento das estacas, bem como estacas armazenadas em ambiente refrigerado apresentaram melhores resultados do que as mantidas em temperatura ambiente. Os tipos de recobrimento que melhor conservaram as estacas, em ordem decrescente de resultados, foram o saco plástico, parafina no ápice e vermiculita umedecida na base, parafina no ápice, película de amido e sem recobrimento. Conclui-se que o método mais prático foi embalar as estacas em sacos plásticos por não necessitar de fonte de calor para o preparo da película. Quanto maiores os períodos de armazenamento, menores desenvolvimentos de brotos, raízes e rizomas; os melhores resultados foram obtidos com estacas colhidas na primavera e armazenadas em ambiente refrigerado. / The world market of floriculture, generates an annual flow of US$ 7billion, is currently based on countries like The Netherlands, Germany, Italy, Colombia, Costa Rica, Ecuador, Kenya, Thayland, Malaysia, Israel and the USA. The Brazilian contribution to the total world market is approximately 0.3%, where the mains exports are cuttings, bulbs, tropical fresh cut flowers and foliages. Brazil, however, has a great potential to increase its export of flowers and other ornamental plants through the better organization of producers, professionalization of the sector, government support and technical development. The use of simple storage techniques, would enable the transport through other means than airplanes, consequently reducing costs and adding extra shelf life to the product, creating a quality differentiation in relation to competitors. This work was aimed at comparing five types of coating of Cordyline rubra Hügel cuttings (starch film, paraffin paste at the apex, paraffin past at the apex associated with moist vermiculite at the base of the cuttings, plastic bags or no coating), seasonality (cuttings harvested during spring or autumn), two types of enviromental temperatures (refrigeration under 10ºC or environmental temperature between 22-32ºC) and different lengths of time on storage (30, 60, 90 or 120 days), in order to reduce their biologycal activity, water loss and pathogen attacks. This specie is very appreciated as an ornamental plant due to the beauty of their foliage and is exported as cuttings of different sizes. The experiment was carried out at the Departament of Plant Production at "Luiz de Queiroz" College of Agriculture, University of Sao Paulo, in Piracicaba City, Sao Paulo State, Brazil. A total of 615 cuttings were used, each measuring 30 cm by 3 cm diameter. A control group of 15 cuttings without storage was planted on rooting bed. Each treatment was comprised of 30 pre-coated cuttings (types of coating), stored at different periods (30.60, 90 or 120 days) and split into 2 sub-treatments of 15 cuttings, either stored at room temperature or under refrigeration, summing up 120 cuttings. After storage, each cutting had 3 cm excised from its base, prior to being treated with IBA 10.000 mg/L and placed at rooting beds. After 90 days, the following parameters were assessed: percentage of cuttings showing growth and development, number and fresh and dry matter of the shoots, roots and rhizoms. It was observed that cuttings obtained during the spring, showed better rooting and production of biomass. The shorter the storage periods the better the cutting sprouting. Cuttings stored under refrigeration showed better results than kept under room temperature. The types of coatings which best supported the longevity of the cuttings, in decrease order, were: plastic bag, paraffin paste at the apex and moist vermiculite at the base, paraffin on the apex, starch film and no coating. Such results allow to conclude that the most practical coating technique was found to be the use of plastic bags, which did not need heating for the prepare of the film. The longer the storage time the smallest the number of viable cuttings; best results where observed for cuttings harvested during the spring and kept under refrigeration storage.
25

Three essays on constrained markets

Siegel, Ryan 12 June 2012 (has links)
The three essays in this dissertation progressively answer the following questions: (a) How important are constraints? (b) Who benefits from removing constraints? (c) When does a constraint for a single market predominantly affect closely related markets? These questions are applied in the context of time, weather, and minimum wage constraints, respectively. The first essay demonstrates that constraints matter. A data envelopment analysis capacity utilization methodology is used to measure impacts on sales from a sequential relaxation of the time and income constraints. Using a subsample bootstrap to estimate confidence intervals, results show that time matters more than income, particularly in fall and winter when other activities compete for gardening time. The second essay shows that the poor are least likely to gain from the relaxation of non-income constraints. A theory of demand is developed in which consumers face multiple constraints. Then, a structural model is used to econometrically estimate the effect of global warming on demand, using nursery data on flowering plants. The model shows that there exists a tipping point around 64 degrees Fahrenheit, above which demand ceases to be climate-constrained. The third essay shows that a constraint in a single market can sometimes have more profound consequences on other, more distantly related markets. First, it is proven that if a series of markets are structured like a chain-- where only own and neighboring prices matter--then a shock to one market decreases with distance. The case of minimum wages in Oregon is investigated using a large panel dataset for all workers in Oregon using a first difference econometric model. It is determined that the ripple effects of the minimum have even larger effects on higher-wage earners, disconfirming the chain pattern. High substitutions between low and high wage groups may explain the pattern. Altogether the essays further the understanding of constraints to demonstrate that (a) constraints significantly affect economic outcomes, (b) if one constraint is lifted, those individuals alternately-constrained are left behind from any benefits, and (c) constraints to a single market may have unintended and sometimes larger effects on 'farther' markets. / Graduation date: 2012
26

Sazonalidade, refrigeração e diferentes tipos de recobrimento na conservação pós-colheita de estacas de cordiline (Cordyline rubra Hügel). / Seasonality, refrigeration and different types of coating on the postharvest conservation of Cordyline rubra Hügel cuttings.

Nelson Mamoru Sakamoto 06 June 2005 (has links)
O mercado mundial de floricultura gera um fluxo de quase US$ 7bilhões anuais, atualmente concentrado em países como Holanda, Alemanha, Itália, Colômbia, Costa Rica, Equador, Quênia, Tailândia, Malásia, Israel e EUA. O Brasil ainda contribui pouco, aproximadamente 0,3% do total, sendo a participação brasileira concentrada na exportação de mudas, bulbos, flores e folhagens tropicais. O Brasil possui grande potencial exportador de flores e plantas ornamentais através da organização dos produtores, profissionalização do setor, apoio governamental e desenvolvimento técnico. O emprego de técnicas simples de armazenamento poderia viabilizar o transporte por modais que não o aéreo, reduzindo custos e podendo prolongar a vida útil dos produtos, criando um diferencial de qualidade em relação aos concorrentes. Este trabalho compara cinco diferentes tipos de recobrimento em estacas de Cordyline rubra Hügel (película amilácea, pasta de parafina no ápice, pasta de parafina no ápice e vermiculita umedecida na base, saco plástico ou sem recobrimento), sazonalidade (estacas coletadas durante primavera ou outono), dois ambientes de armazenamento (ambiente refrigerado a 10ºC ou temperatura ambiente 22-32ºC) e diferentes períodos de armazenamento (30, 60, 90 ou 120 dias), a fim de reduzir sua atividade biológica, perda de água e ataque de patógenos. Foi escolhida esta espécie por ser muito apreciada como planta ornamental devido à beleza de suas folhas, e exportada na forma de estacas de diferentes tamanhos. O experimento foi conduzido nas dependências do Departamento de Produção Vegetal da Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, no município de Piracicaba, Estado de São Paulo. Foram utilizadas 615 estacas com 30 cm de comprimento por 3 cm de diâmetro. Um lote testemunha sem armazenamento de 15 estacas foi colocado em leito de enraizamento. Cada tratamento foi composto por 30 estacas pré-tratadas (tipos de recobrimento), submetidas a diferentes períodos de armazenamento (30, 60, 90 ou 120 dias), sendo divididos em 2 sub-tratamentos de 15 estacas (temperatura ambiente ou refrigerada), totalizando 120 estacas. Após o armazenamento foram cortados 3 cm da base de cada estaca, em seguida tratadas com IBA a 10.000 mg/L e colocadas em leito de enraizamento. Após 90 dias foram avaliados os seguintes parâmetros: porcentagem de desenvolvimento, número e massas de matéria fresca e seca de brotos, raízes e rizomas. Observou-se que as estacas colhidas na primavera apresentaram melhor enraizamento e produção de massas secas e frescas. Os menores períodos de armazenamento proporcionam melhor desenvolvimento das estacas, bem como estacas armazenadas em ambiente refrigerado apresentaram melhores resultados do que as mantidas em temperatura ambiente. Os tipos de recobrimento que melhor conservaram as estacas, em ordem decrescente de resultados, foram o saco plástico, parafina no ápice e vermiculita umedecida na base, parafina no ápice, película de amido e sem recobrimento. Conclui-se que o método mais prático foi embalar as estacas em sacos plásticos por não necessitar de fonte de calor para o preparo da película. Quanto maiores os períodos de armazenamento, menores desenvolvimentos de brotos, raízes e rizomas; os melhores resultados foram obtidos com estacas colhidas na primavera e armazenadas em ambiente refrigerado. / The world market of floriculture, generates an annual flow of US$ 7billion, is currently based on countries like The Netherlands, Germany, Italy, Colombia, Costa Rica, Ecuador, Kenya, Thayland, Malaysia, Israel and the USA. The Brazilian contribution to the total world market is approximately 0.3%, where the mains exports are cuttings, bulbs, tropical fresh cut flowers and foliages. Brazil, however, has a great potential to increase its export of flowers and other ornamental plants through the better organization of producers, professionalization of the sector, government support and technical development. The use of simple storage techniques, would enable the transport through other means than airplanes, consequently reducing costs and adding extra shelf life to the product, creating a quality differentiation in relation to competitors. This work was aimed at comparing five types of coating of Cordyline rubra Hügel cuttings (starch film, paraffin paste at the apex, paraffin past at the apex associated with moist vermiculite at the base of the cuttings, plastic bags or no coating), seasonality (cuttings harvested during spring or autumn), two types of enviromental temperatures (refrigeration under 10ºC or environmental temperature between 22-32ºC) and different lengths of time on storage (30, 60, 90 or 120 days), in order to reduce their biologycal activity, water loss and pathogen attacks. This specie is very appreciated as an ornamental plant due to the beauty of their foliage and is exported as cuttings of different sizes. The experiment was carried out at the Departament of Plant Production at “Luiz de Queiroz” College of Agriculture, University of Sao Paulo, in Piracicaba City, Sao Paulo State, Brazil. A total of 615 cuttings were used, each measuring 30 cm by 3 cm diameter. A control group of 15 cuttings without storage was planted on rooting bed. Each treatment was comprised of 30 pre-coated cuttings (types of coating), stored at different periods (30.60, 90 or 120 days) and split into 2 sub-treatments of 15 cuttings, either stored at room temperature or under refrigeration, summing up 120 cuttings. After storage, each cutting had 3 cm excised from its base, prior to being treated with IBA 10.000 mg/L and placed at rooting beds. After 90 days, the following parameters were assessed: percentage of cuttings showing growth and development, number and fresh and dry matter of the shoots, roots and rhizoms. It was observed that cuttings obtained during the spring, showed better rooting and production of biomass. The shorter the storage periods the better the cutting sprouting. Cuttings stored under refrigeration showed better results than kept under room temperature. The types of coatings which best supported the longevity of the cuttings, in decrease order, were: plastic bag, paraffin paste at the apex and moist vermiculite at the base, paraffin on the apex, starch film and no coating. Such results allow to conclude that the most practical coating technique was found to be the use of plastic bags, which did not need heating for the prepare of the film. The longer the storage time the smallest the number of viable cuttings; best results where observed for cuttings harvested during the spring and kept under refrigeration storage.
27

Construction de l'architecture et des composantes visuelles d'un buisson ligneux d'ornement : le rosier / Construction of the architecture and visual components of a woody ornamental bush : the rose tree

Garbez, Morgan 23 November 2016 (has links)
Les buissons ligneux forment un modèle végétal clé pour répondreaux préoccupations sociales et environnementales.Usuellement transposé sur le modèle arborescent, leur développementarchitectural reste encore peu compris et peu étudiéau regard de leur qualité visuelle. Pour cerner et anticiper cesattentes, une méthodologie pluridisciplinaire visant le managementde la qualité visuelle des plantes d’ornement est proposée.Elle intègre l’architecture des plantes avec sa plasticité phénotypiqueet la perception de leur apparence visuelle. Sur un rosierbuisson : Rosa hybrida L. ‘Radrazz’, l’étude montre commentl’analyse architecturale avec ses outils de modélisation, l’analysesensorielle et d’image peuvent former un cadre scientifi quecohérent visant cet objectif, et transposable à d’autres taxons.Sur rosiers virtuels, et réels exposés à un gradient lumineux, l’apparencevisuelle peut être caractérisée objectivement au moyend’épreuves sensorielles sur vidéode plante en rotation à différentsstades. La vidéo permet aux sujets une meilleure représentationmentale de la plante en 3D, et ainsi une descriptionplus complète et fi able de l’apparence visuelle ; puis de prédirecette description en intégrant statistiquement l’analyse d’imagede plusieurs facettes de la plante. Certaines variables architecturalespertinentes, et de nombreuses équivalentes, potentiellementintéressantes pour étudier le développement des buissonsau cours de leur cycle de vie, permettent de prédire voire d’expliquerl’élaboration des composantes visuelles d’un cultivar. / Shrubs form a key plant model to meet social and environmentalconcerns. Usually transposed on the tree model, their architecturaldevelopment is still ill-known and understudied to address visualquality. To identify and anticipate such expectations, the visual qualitymanagement of ornamental plants through a multidisciplinarymethodology is proposed. It includes architecture of the plants withits phenotypic plasticity and their visual appearance perception.On a rose bush: Rosa hybrida L. ‘Radrazz’, this work shows howarchitectural analysis with its modeling tools, sensory evaluationand image analysis can form a coherent scientifi c framework toface up to such a purpose, and be transposed for other taxa. Onvirtual rose bushes, and real ones exposed to a light gradient, thevisual appearance can be characterized objectively by means ofsensory tests using rotating plant video at different stages.Thevideo stand enables a better mental representation of the plant 3Dby the subjects, leading to a more complete and reliable descriptionof the plant visual appearance; then to predict this descriptionthrough statistically integrated image analysis of multiple plantfacets. Some relevant architectural variables, with numerousequivalents, potentially interesting to study the architecturaldevelopment of bushes during their life cycle, enabled to predicteven explain how visual components were built for a cultivar. Fora better market responsiveness, this work lays the foundationfor drafting interactive decision and innovation support tools forb
28

Impact de la sélection au XIXe siècle sur la diversité génétique du rosier cultivé en France (Rosa sp.) / Impact of breeding during the 19th century on the genetic diversity of French cultivated roses (Rosa sp.)

Liorzou, Mathilde 22 November 2016 (has links)
L’hybridation avec des ressources génétiques allochtones est largement pratiquée chez les plantes ornementales pour introduire de nouveaux caractères. Au cours du 19e siècle, âge d’or de la sélection des rosiers en France, des rosiers asiatiques ont été introduits en Europe. L’objectif ici est d’étudier l’évolution de la diversité génétique des rosiers cultivés en France au cours de cette période. La diversité a été étudiée à l’échelle du génome puis à l’échelle de gènes candidats codant pour des caractères potentiellement sélectionnés au cours du 19e siècle. Un échantillon de 1228 rosiers illustrant la diversité génétique des rosiers français cultivés à cette période a été génotypé avec 32 microsatellites. Une large diversité, structurée en seize groupes génétiques et une différenciation entre les rosiers anciens européens et les rosiers asiatiques ont été détectées. Un déplacement du fond génétique des hybrides cultivés d’un type européen vers un type asiatique a été observé au cours du 19e siècle. Les croisements fréquents et/ou la sélection pour des caractères présents chez les rosiers asiatiques ont pu induire cette évolution. Certains caractères phénotypiques, comme la remontée de floraison, deviennent prépondérants. Onze gènes candidats ont été séquencés et leur diversité a été analysée sur un sous-échantillon de 365 rosiers. Parallèlement au fond génétique, certains gènes présentent un rapprochement génétique vers des allèles asiatiques. Pour le gène KSN, une augmentation de la fréquence d’allèles portant le rétrotransposon copia, responsable de la remontée de floraison, est observée. / Innovation in ornamental plant breeding is commonly obtained by hybridization with newly introduced genetic resources. During the 19th century, golden age for rose breeding in France, Asian roses were introduced in Europe. Our objective here was to study and explain the evolution of rose genetic diversity in France during this period of time. The diversity was studied at the genome scale and at the candidate gene scale. A large sample of 1228 garden roses illustrating the French rose diversity from this period of time was genotyped with 32 microsatellites markers. A wide diversity, structured into sixteen genetic groups, was observed. A geneticdifferentiation was detected between ancient European and Asian accessions and a continuous temporal shift was observed in cultivated hybrids from a European to an Asian genetic background during the 19th century.Frequent crosses with Asian roses along the 19th century and/or selection for Asiatic traits may have induced this shift. Some phenotypic traits, like continuous flowering, became overriding traits. Eleven candidate genes, which were potentially selected during the 19th century, were sequenced and their diversity was analyzed on a subsample of 365 roses. Simultaneously to the genetic background, some genes are gettingcloser to Asian alleles. For the KSN gene, an increase in the frequency of alleles carrying the retrotransposon copia, responsible for continuous flowering, is observed.

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