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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

Períodos de vernalização em bulbilhos semente livre de vírus de cultivares nobre de alho no cerrado brasileiro / Vernalization periods in virus free seed bulbils noble garlic cultivars in brazilian cerrado

Nardini, João Paulo Calore [UNESP] 26 August 2016 (has links)
Submitted by JOÃO PAULO CALORE NARDINI null (jpnardini@hotmail.com) on 2016-10-24T12:05:01Z No. of bitstreams: 1 DISSERTAÇÃO Nardini_João Paulo Calore.pdf: 1864756 bytes, checksum: 758f33f67743ef8d607cc4576761e161 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-10-31T13:08:14Z (GMT) No. of bitstreams: 1 nardini_jpc_me_bot.pdf: 1864756 bytes, checksum: 758f33f67743ef8d607cc4576761e161 (MD5) / Made available in DSpace on 2016-10-31T13:08:14Z (GMT). No. of bitstreams: 1 nardini_jpc_me_bot.pdf: 1864756 bytes, checksum: 758f33f67743ef8d607cc4576761e161 (MD5) Previous issue date: 2016-08-26 / O alho (Allium sativum L.) não possui semente verdadeiramente botânica, sendo assim, sua única via de propagação se dá vegetativamente, fato este que implica regularmente numa infecção viral mista, se tornando uma das principais causas da redução de produtividade. Alguns produtores já possuem acesso a semente de alho ‘Livre de Vírus’, no entanto, ainda utilizam de vernalização antiquada, preconizada pela pesquisa para alho semente infectada por vírus (material comum para maioria dos produtores nacionais), e quando utilizada pelos produtores em alho-semente ‘Livre de Vírus’, vem acarretando problemas principalmente para os produtores do cerrado, onde o plantio é antecipado. Neste estudo foi avaliado o efeito da temperatura de vernalização a 4ºC combinada por diferentes períodos (30, 40, 50 e 60 dias) em bulbilho-semente livre de vírus. O experimento foi conduzido de acordo coma a safra da cultura na região (março à outubro), em fazendas localizadas nos municípios de Santa Juliana (MG) e Campo Alegre de Goiás (GO): regiões de cerrado que se destacam atualmente pela produção de alho nobre no Brasil. Foram avaliadas três das principais cultivares existentes no mercado, sendo elas: Caçador, Quitéria e Ito. As maiores produtividades de bulbos comerciais para as cultivares Caçador em Campo Alegre de Goiás (GO) 2014 e Santa Juliana (MG) 2014 foram nos tratamentos de 30 e 40 dias de vernalização, respectivamente, conciliando produtividades de 11,3 t.ha-¹ e 12,4 t.ha-¹, com boa qualidade de bulbo. A cultivar Quitéria em Campo Alegre de Goiás (GO) 2014 alcançou melhor resultado com tratamento de 51 dias de vernalização, atingindo produtividade de 16,8 t.ha-¹. ‘Ito’ 2015 em Campo Alegre de Goiás (GO) e Santa Juliana (MG) atingiu produtividades interessantes do ponto de vista comercial aos 30 e 40 dias de vernalização, respectivamente, atingindo 16,7 e 17,1 t.ha-¹. Também foi avaliado que para bulbilhos livre de vírus ‘Caçador’, se demonstraram menos susceptíveis à formação de bulbos ‘charutos’ em baixos períodos de vernalização, do que bulbilhos convencionais. Em longos períodos de vernalizações, ‘Caçador’ livre de vírus é mais sensíveis ao aparecimento de brotações laterais do que o convencional. Verificou-se ainda que o efeito dos tratamentos de vernalização teve influência direta no IVD na semeadura, tempo de diferenciação (dias), número de folhas na diferenciação, ciclo da cultura (dias), incidência de bulbos charutos e brotações laterais em todas as cultivares avaliadas. Observou-se que do ponto de vista prático, que não é recomendável a utilização de extensos períodos de vernalização para produção de semente, já que esta possui notável relação com o estímulo à produção de bulbilhos com mais de uma gema. / Garlic (Allium sativum L.) does not really have truly botanic seeds; therefore, its only way of propagation is vegetatively, which regularly implies in a mixed viral infection that becomes the major cause of reduced productivity. Some producers already have access to garlic seed 'Virus Free', however, still use old-fashioned vernalization, recommended by the search for seed infected garlic virus (common material for most domestic producers), and when used by producers in garlic-seed 'Virus Free', has been causing problems especially for the cerrado producers, where planting is anticipated. This study evaluated the effect of vernalization temperature of 4 ° C combined for different periods (30, 40, 50 and 60 days) in virus free bulbil seed. The experiment was conducted in accordance eat the harvest of culture in the region (march to october), in farms located in the cities of Santa Juliana (MG) and Campo Alegre de Goiás (GO): cerrado regions which are currently out for garlic production noble in Brazil. Were evaluated three of the main existing cultivars on the market, which are: Caçador, Quiteria and Ito. The highest commercial bulbs for Caçador in Campo Alegre de Goiás (GO) 2014 and Santa Juliana (MG) in 2014 were the treatments of 30 and 40 days of vernalization, respectively, combining yields of 11.3 t ha-¹ and 12.4 t ha-¹, with good quality bulb. Quitéria in Campo Alegre de Goiás (GO) in 2014 achieved a better result with treatment of 51 days of vernalization, reaching productivity of 16.8 t ha-¹. 'Ito' 2015 Campo Alegre de Goiás (GO) and Santa Juliana (MG) reached interesting productivities commercial point of view at 30 and 40 days of vernalization, respectively, reaching 16.7 and 17.1 t ha-¹. It was also reported that for virus free bulbils of "Caçador", have proved less susceptible to the formation of bulbs 'cigar' in low periods of vernalization than conventional bulbils. Over long periods of vernalizações 'Caçador ' virus free is more sensitive to the onset of side shoots than conventional. It was also found that the effect of vernalization had a direct influence on the IVD during sowing, differentiation time (days) number of leafs in the differentiation, culture cycle (days), the incidence of ‘cigars’ bulbs and side shoots in all cultivars evaluated. It was observed that from a practical point of view, it is not recommendable to use long periods of vernalization for seed production, since it has remarkable relationship to stimulate production of bulbils over a gem.
22

The impact of predevernalization and plasticulture treatments on bolting of celery (Apium graveolens L.) grown in Quebec /

Cote, John Christopher. January 2002 (has links)
No description available.
23

Evaluation of the risks and profitability for early planting dates and bolt reducing strategies for Quebec celery production

Dessureault, Darlene January 2003 (has links)
No description available.
24

Short term response of European wheat populations to contrasted agro-climatic conditions : a genetic analysis and first step towards development of epigenetic markers in earliness gene VRN-A1 / Réponse à court terme des populations de blé européens aux conditions agro-climatiques contrastées : analyse génétique et première étape vers le développement de marqueurs épigénétiques dans les gènes précoces VRN-A1

Khan, Abdul Rehman 27 June 2013 (has links)
La diversité génétique est à l’origine de l'évolution et de l'adaptation des pop. et des espèces. Dans les agrosystèmes, la div. gén. intra-population est d'une importance majeure : d'une part, elle peut fournir un effet tampon contre les variations climatiquesinterannuelles et les stress biotiques, et d'autre part cette div. peut permettre l’adaptation locale des pop., du fait de leur évolution sous l’effet des pressions sélectives spécifiques aux conditions locales de la région, particulièrement dans le cas d’uneintrod. dans un nouvel environnement. En raison de son importance socio-économique et de son aire de culture étendue, le blé a été choisi comme espèce modèle dans cette étude, en se focalisant sur l’étude de la précocité de de floraison, un caractère adaptatif majeur qui permet au blé de croître sur une large gamme de conditions écologiques et climatiques. Ce projet de thèse a pour objet l’analyse de l'impact de la diversité int.-pop. sur la réponse adaptative à court terme de pop. soumises à des conditions agro-climatiques contrastées, ce par l'étude des variations génétiques, épigénétiques et phénotypiques.L'absence de marqueurs épig. disponible pendant la thèse a conduit à développer 2 études complémentaires. Dans une 1ère partie, sept var. pays. (pop. conservées à la ferme) et une variété moderne ont été distribuées et cultivées pendant trois ans dans sept fermes localisées dans trois pays d'Europe, puis étudiées pour leur réponse aux différentes conditions agro-climatiques, sous l’angle de leurs variations phénotypiques et génotypiques. Dans une 2nde partie, l'effet de la vernalisation sur le profil de méth. de l'ADN du gène VRN-A1 a été étudié, constituant une 1ère étape vers le développement de marqueurs épig. Les résultats de la 1ère partie de l'étude ont révélé que l'histoire de la conservation des var. pays. a fortement influencé leur div. gén. et leur structure génétique fine. Les var. pays. conservées ex situ montrent une faible div. gén., avec une struct. génétique simple. Les var. pays. et les mélanges conservés in situ révèlent une div. gén. plus élevée, avec une struct. génétique complexe. Une différenc. spatio-temporelle génétique et phénotypique a été observée, en relation avec le niveau de diversité initial et avec la complexité de structure des var. pays. Les variétés traditionnelles se différencient plus nettement que les var. modernes, ce qui plaide en faveur de utilisation dans des systèmes d'agriculture biologique et à bas intrants. De façon intéressante, une différenc. phénotypique significative a été observée pour les var. qui présentaient une div. gén. initiale très faible, ce qui suggère que d’autres facteurs, par exemple épig., pourraient intervenir dans les adaptations misesen évidence. La 2nde partie a permis de mettre en évidence un profil de méth. intéressant de l’ADN de VRN-A1 : sur plantes non-vernalisées, ce gène présente des niveaux élevés de méth. dans la partie centrale du gène, mais pas en début et fin de gène. De plus, une partie du 1er intron montre une augmentation significative du niveau de méth. de l'ADN suite au traitement au froid. Ce changement de méth. est positivement associé au niveau d'expression du gène. Si la compréhension du rôle de cette méth. sur la régulation de VRN-A1 nécessite des analyses complémentaires, cette étude a permis de caractériser les modifications de méth. de VRN-A1 en réponse au froid et constitue une 1ère étape vers l’identification de possibles epiallèles dans nos pop. et fournit une base à la construction de marqueurs permettant de suivre la variabilité épig. dans différentes pop. En conclusion, cette étude apporte des connaissances utiles pour une meilleure compréhension de l’origine et l'évolution de la div. gén. présente dans les var. pays. Elles permettront de dvper des méthodes de conservation et desélection à la ferme, en tenant compte de l'importance de la div. int.-pop., afin de rép. aux contraintes posées par l'agriculture bio. / Biodiversity provides the raw material for evolution and adaptation of populations and species. In agricultural biodiversity, the within-population genetic diversity is of major importance. On one hand, it can provide a buffering effect against the year-to-year variation of climate or biotic pressures and on the other hand diversity serves as a resource for the population to respond to selective pressures due to specific local conditions, thus allowing for local adaptation, particularly in the case where a population is introduced into a new location. Due to its wide geographic distribution indicating a high adaptiveotential and its socio-economic importance, wheat was chosen as model crop in this study. Flowering time is a major adaptive trait which has allows wheat to grow over a wide range of ecological and climatic conditions. This PhD study was designed to gain insights about the influence of within population diversity on the short term response of populations to contrasting agro-climatic conditions by studying the genetic, epigenetic and phenotypic variation. But due to the lack of prior existence of epigenetic markers, this thesis study is divided of two parts: In the first part, European wheat populations coming from a set of seven farmer and one modern varieties, each of which was grown on seven farms (distributed across Europe) for three years, were used to study their short term response to contrasting agro-climatic conditions in Europe by analysing their phenotypic and genotypic variations. For the second part the effect of vernalization on the DNA methylation profile of theVRN-A1 gene in winter wheat was studied as a first step towards the development for the epigenetic marker in this gene.The results from the first part of the study revealed that conservation history of these farmer varieties strongly influenced the genetic diversity and fine genetic structure. Ex situ conserved farmer varieties showed low genetic diversity and simpler structure whereas in situ conserved farmer varieties and mixtures revealed higher level of genetic diversity and complex genetic structure. Genetic and phenotypic spatio-temporal differentiation depending upon the level of diversity and structural complexity of the farmer variety was observed. The traditional varieties tend to become more differentiated than the modern variety arguing in favour of use of these diverse traditional (farmer) varieties in organic and low input agriculture systems. Interestingly, a significant phenotypic differentiation for varieties with very low genetic diversity has also been observed in this study, which gives indication of a possible role of epigenetic variation in the process of evolution.From the second part of the study (effect of vernalization on the DNA methylation profile of the VRN-A1 gene), it was found that in addition to the detection of gene body methylation across the VRN-A1 gene, we identified a region within intron 1 that shows significant increase in DNA methylation in response to vernalization treatment that is positively correlated with the gene expression. Although the role of this shift in gene regulation is still unclear due to time limitations in the thesis and the small number of genotypes analysed, this study will provide a good material towards future identification of new epialleles and the development of epigenetic markers to study the epigenetic variability of these populations.This study at large provides useful knowledge on the understanding of farmers' varieties evolutionary response to be used in the development of different breeding and conservation approaches for organic agriculture, taking into consideration of the importance of within population diversity, to satisfactorily address the problems of organic agriculture.
25

Role of light and temperature in the flowering of Watsonia species.

Mtshali, Ntombizamatshali Prudence. January 2006 (has links)
The role of light and temperature on flowering of South African Watsonia species were evaluated to assess the potential for this genus as a commercial flower crop. Species were selected that represent different climatic regions of South Africa, with the aim of understanding how ecologically distinct species perform under cultivation. The four selected species were W. borbonica and W. tabularis (winter-rainfall area), W. angusta (shared rainfall) and W. pillansii (summer-rainfall area). In order to establish the optimum temperature required for flowering, plants were exposed for 12 weeks to three temperature regimes (12/7 °C, 21/15 °C and 29/21 °C) after attaining their first and/or second leaves. A temperature shift of 12/7 °C was used to assess if the plants had a vemalisation requirement. Controls were maintained under 25 % shade under natural conditions, with an average temperature of 24/7 °C. An elevated temperature of 29/21 °C was detrimental to plant growth. Moderate temperatures of 21/15 °C significantly (P<0.001) increased the height and the number of leaves produced per plant relative to the 12/7 °C treatment. These temperatures significantly (P<0.001) increased the total number of flowers produced per plant compared to low temperatures. However, flowering percentage and quality of flowers were reduced. A low temperature regime of 12/7 °C was efficient in satisfying vernalisation requirements and inducing flowering in four selected species. However, the total number of leaves produced per plant was signifcantly reduced. The summer-rainfall species, W pillansii, displayed a qualitative response to vernalisation, as no flowering was observed in non-vernalised plants. Two winter-rainfall species, W borbonica and W. tabularis, demonstrated a quantitative response to vernalisation. These species flowered at non-vernalising temperatures. W angusta behaved like the winter-rainfall species in terms of flowering. Overall, a vernalisaton treatment marginally reduced days to flower while flowering percentage was increased compared to other temperature regimes. However, there was no increase in the total number of flowers produced per plant. Low temperatures were not only effective for flower induction, but also for releasing corm dormancy, thus synchronising growth. Storing corms at either 4 or 10 QC resulted in 100 % sprouting within 4-6 weeks. The role of daylength in flowering of Watsonia plants was established by subjecting plants to long days (LO) of 16 h light and 8 h dark and to short days (SO) of 8 h light and 16 h dark. The number of leaves and flowering were significantly (P<0.01) promoted under the LO regime. However, there was strong temperature and daylength interaction in terms of flowering potential, as at low temperatures flowering was induced irrespective of daylength. In W. pillansii, flowering was obtained under both regimes (LO and SO) applied at the second leaf stage. Flowering in W. borbonica and W. tabularis was only observed under the LO regime at the second leaf stage. In both species, flowering was also obtained in SD-treated plants, provided treatment occurred after the formation of the third leaf. However, the total number and quality of flowers were reduced. To examine the effect of light intensity on flowering, plants at different developmental stages (first and/or second or beyond the third leaf stage) were exposed to photosynthetically active radiation (PAR) of 150 jJmol m-2s-1 or 39.5 jJmol m-2s-1 for 7 weeks. Exposure to low light intensity at either developmental stage compromised leaf quality. No flowering was observed following low light intensity treatment during the first to third leaf stages, even though plants were exposed to low temperature and LO regimes, both of which promoted flowering. Observation of the shoot apical meristem revealed that the second leaf stage was critical as the anatomical transition to flowering occurred at this level. When beyond the third leaf stage, low light intensity did not prevent flowering. However, the number of flowers produced per plant was reduced compared to plants maintained at 150 jJmol m-2s-1. Thus, light intensity played a role in both plant morphogenesis and flowering. LDs were effective in promoting vegetative growth whereas high light intensity and low temperature regimes played pivotal roles in flower induction. This makes them useful horticulture tools to produce desirable Watsonia plants for commercialisation. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
26

Short term response of European wheat populations to contrasted agro-climatic conditions : a genetic analysis and first step towards development of epigenetic markers in earliness gene VRN-A1

Khan, Abdul Rehman 27 June 2013 (has links) (PDF)
Biodiversity provides the raw material for evolution and adaptation of populations and species. In agricultural biodiversity, the within-population genetic diversity is of major importance. On one hand, it can provide a buffering effect against the year-to-year variation of climate or biotic pressures and on the other hand diversity serves as a resource for the population to respond to selective pressures due to specific local conditions, thus allowing for local adaptation, particularly in the case where a population is introduced into a new location. Due to its wide geographic distribution indicating a high adaptiveotential and its socio-economic importance, wheat was chosen as model crop in this study. Flowering time is a major adaptive trait which has allows wheat to grow over a wide range of ecological and climatic conditions. This PhD study was designed to gain insights about the influence of within population diversity on the short term response of populations to contrasting agro-climatic conditions by studying the genetic, epigenetic and phenotypic variation. But due to the lack of prior existence of epigenetic markers, this thesis study is divided of two parts: In the first part, European wheat populations coming from a set of seven farmer and one modern varieties, each of which was grown on seven farms (distributed across Europe) for three years, were used to study their short term response to contrasting agro-climatic conditions in Europe by analysing their phenotypic and genotypic variations. For the second part the effect of vernalization on the DNA methylation profile of theVRN-A1 gene in winter wheat was studied as a first step towards the development for the epigenetic marker in this gene.The results from the first part of the study revealed that conservation history of these farmer varieties strongly influenced the genetic diversity and fine genetic structure. Ex situ conserved farmer varieties showed low genetic diversity and simpler structure whereas in situ conserved farmer varieties and mixtures revealed higher level of genetic diversity and complex genetic structure. Genetic and phenotypic spatio-temporal differentiation depending upon the level of diversity and structural complexity of the farmer variety was observed. The traditional varieties tend to become more differentiated than the modern variety arguing in favour of use of these diverse traditional (farmer) varieties in organic and low input agriculture systems. Interestingly, a significant phenotypic differentiation for varieties with very low genetic diversity has also been observed in this study, which gives indication of a possible role of epigenetic variation in the process of evolution.From the second part of the study (effect of vernalization on the DNA methylation profile of the VRN-A1 gene), it was found that in addition to the detection of gene body methylation across the VRN-A1 gene, we identified a region within intron 1 that shows significant increase in DNA methylation in response to vernalization treatment that is positively correlated with the gene expression. Although the role of this shift in gene regulation is still unclear due to time limitations in the thesis and the small number of genotypes analysed, this study will provide a good material towards future identification of new epialleles and the development of epigenetic markers to study the epigenetic variability of these populations.This study at large provides useful knowledge on the understanding of farmers' varieties evolutionary response to be used in the development of different breeding and conservation approaches for organic agriculture, taking into consideration of the importance of within population diversity, to satisfactorily address the problems of organic agriculture.
27

Biologie, semenářské vlastnosti a zakládání porostů kostivalu lékařského (\kur{Symphytum officinale }L.) / Biology, seed characteristics and growth establishment of comfrey (\kur{Symphytum officinale }L.)

KOVÁŘOVÁ, Jaroslava January 2016 (has links)
The thesis titled "Biology, seed characteristics and growth establishment of common comfrey (Symphytum officinale L.)" dealt with the evaluation methods of reproduction comfrey and evaluation of the impact of environmental conditions to the grow of comfrey. Further it dealt with germination tests and their statistical evaluation while respecting the specific work with seeds. They were evaluated seed characteristics, which are reflected in the growth of these plants arising both in soil and in a laboratory environment. Literary part gave information about biology, characteristics, morphology, prevention and regulation of comfrey even more its cultivation, nutrition of the grassland and seed characteristics, germination and dormancy. In the final section of work was monitored coverage, botanical images, representation of herbaceous species growing near comfrey. The study also discussed vernalization, size of comfrey leaves, growth and development depending on the content of nutrients (soil fertility) and water in the soil and on the number of cuts to its growth. There were designed a suitable ways of reproduction and growing of comfrey.
28

Frigoconservação e vernalização de mudas de morangueiro (Fragaria x ananassa Duch.) produzidas em sistema de vasos suspensos. / Storage cold and vernalization of strawberries runner (fragaria x ananassa duch.) produced in suspend pots system.

Verdial, Marcelo Fontanetti 14 May 2004 (has links)
Com o objetivo de estudar o sistema de produção de mudas de morangueiro em vasos suspensos e a aplicação das técnicas de frigoconservação e vernalização nas mudas produzidas nesse sistema, foram realizados quatro experimentos no Departamento de Produção Vegetal, ESALQ/USP, Piracicaba/SP, no período compreendido entre janeiro de 2000 e junho de 2003. No primeiro experimento comparou-se o sistema de produção de mudas em vasos suspensos com o sistema convencional. Foram avaliados: matéria seca, teor de carboidratos totais e percentagem de sobrevivência de mudas. Foram utilizadas as cultivares IAC-Campinas, Pelican e IAC-Guarani. Foi utilizado o delineamento experimental em esquema fatorial 3x2 (três cultivares e dois sistemas de produção de mudas), com três repetições. As mudas produzidas em vasos suspensos apresentaram maior percentagem de sobrevivência e maiores teores de carboidratos totais. O segundo e terceiro experimentos tiveram como objetivo avaliar o uso da técnica de frigoconservação em mudas produzidas no sistema de vasos suspensos. As mudas foram acondicionadas em sacos de polietileno e frigoconservadas durante 120 dias em uma B.O.D. a -1 + 1oC. Foram então retiradas da câmara fria e plantadas em bandejas de poliestireno expandido de 128 células preenchidas com vermiculita. As bandejas foram colocadas em uma câmara nebulizadora, onde permaneceram por 21 dias para enraizamento. Em seguida foram transplantadas para vasos de 250ml e levadas para casa de vegetação. Foi avaliada a percentagem de sobrevivência das mudas. No segundo experimento utilizou-se o delineamento experimental inteiramente ao acaso com cinco cultivares (IAC-Campinas, Dover, Pelican, Sequoia e Sweet Charlie) e nove repetições. No terceiro experimento foi utilizado o esquema fatorial 5x2 (cinco cultivares: IAC-Campinas, Oso Grande, Camarosa, Dover e Sweet Charlie; e dois tratamentos de enraizamento: com e sem ácido indol butírico) com quatro repetições. O sistema de frigoconservação adotado apresenou desempenho insatisfatório devido à baixa percentagem de sobrevivência das mudas. O quarto experimento estudou o efeito da vernalização em mudas de cinco cultivares de morangueiro produzidas no sistema de vasos suspensos. As mudas foram plantadas em vasos de 250 ml, preenchidos com substrato formulado com areia e vermiculita (4:1) e mantidas em casa de vegetação durante seis meses. O delineamento experimental utilizado foi o fatorial 5x2, com cinco cultivares (IAC-Campinas, Dover, Sweet Charlie, Cartuno e Oso Grande) com e sem vernalização das mudas, com quatro repetições. Para vernalização, as mudas foram levadas para câmara fria, à temperatura de 10 + 2ºC, e fotoperíodo de 10 h de luz/dia, durante 28 dias. Em seguida, foram transplantadas para dois locais de cultivo com características climáticas distintas, Piracicaba,SP e Caldas,MG. Foram avaliadas as percentagens de sobrevivência, florescimento, frutificação e emissão de estolhos e o peso da matéria fresca e número de frutos produzidos por planta. A sobrevivência de mudas não foi afetada pela vernalização em nenhuma das localidades. Houve efeito significativo no florescimento e na frutificação das plantas vernalizadas apenas em Piracicaba. O estolonamento de plantas foi mais precoce em Piracicaba. Para todas as cultivares a produção de frutos foi e insignificante e comercialmente inviável em ambas as localidades. / With the objective of studying the runners production system in suspended pots under protected cultivation and the application of techniques of stored cold and vernalization of runners produced by this system, four experiments were conducted in the Department of Crop Production, ESALQ, Piracicaba, SP-Brazil. In the first experiment it was compared the conventional strawberry runners production system with the runner production system in suspended pots. For that, it was measured the dry matter and carbohydrates contents in runners and the survival percentage when the runner were transplanted to field production areas. The cultivars IAC-Campinas, Pelican and IAC-Guarani were used, in an experimental design of factorial arrangement 3x2 (three cultivars and two runners production systems), three replications. The runners produced by the system of suspended pots accumulated higher amount of total carbohydrates and the plant survival rate. The second and third experiments had the objective of evaluating the use of a technique of storage cold in runners produced in the system of suspended pots. After the selection, the runners were conditioned in polyethylene bags and storage cold conditions for 120 days in a B.O.D. at -1+1ºC. After that they were removed of the cold camera and planted in trays of expanded polystyrene of 128 cells with vermiculite. The trays were put in a spray chamber 21 days for rooting. After that hey were transplanted to pots of 250mL and then placed in the greenhouse. It was evaluated the percentage of runners survival. In the second experiment it was used the experimental entirely random design, five strawberry cultivars (IAC-Campinas, Dover, Pelican, Sequoia and Sweet Charlie), and nine repetitions. In the threat experiment the factorial outline used was 5x2 (five cultivars: IAC-Campinas, Big Oso, Camarosa, Dover and Sweet Charlie; and two treatments: with and without indol butyric acid) with four repetitions. The storage cold of strawberry runners produced in system of suspended pots lower percentage of survival of seedlings in the two experiments. Therefore, the system of storage cold was not compatible with the type of storage runners. The fourth experiment had the objective of studying the effect of the runner vernalization of five strawberry cultivars produced in suspended pot system. In order to have availability of strawberry runners during the off season, they were planted in pots of 250 mL, filled out with substrate formulated with sand and vermiculite (4:1) and kept in the greenhouse for six months. Completely randomized blocks with the factorial design 5x2, with five strawberry cultivars (IAC-Campinas, Dover, Sweet Charlie, Cartuno and Big Oso) and two treatments (with and without strawberry runners vernalization). For vernalization, the strawberry runners were taken from cold camera to the temperature of 10 + 2ºC, and fotoperiod of 10 h of light/day for 28 days. After that, they were transplanted for two cultivation places with different climatic conditions, Piracicaba/SP and Caldas/MG. They were analyzed the survival percentages, flower blooming, fructification and emission of stolons and the weight and number of fruits produced by plant. The strawberry runners survival was not affected by the vernalization in none of the places. There were only significant effect on flower appearance and fructification of the vernalized plants, only in Piracicaba. The runner emitions were earlier in Piracicaba. For all strawberry cultivars the production of fruits was very low and the produced fruits were unsuitable for commercialization in both places.
29

Frigoconservação e vernalização de mudas de morangueiro (Fragaria x ananassa Duch.) produzidas em sistema de vasos suspensos. / Storage cold and vernalization of strawberries runner (fragaria x ananassa duch.) produced in suspend pots system.

Marcelo Fontanetti Verdial 14 May 2004 (has links)
Com o objetivo de estudar o sistema de produção de mudas de morangueiro em vasos suspensos e a aplicação das técnicas de frigoconservação e vernalização nas mudas produzidas nesse sistema, foram realizados quatro experimentos no Departamento de Produção Vegetal, ESALQ/USP, Piracicaba/SP, no período compreendido entre janeiro de 2000 e junho de 2003. No primeiro experimento comparou-se o sistema de produção de mudas em vasos suspensos com o sistema convencional. Foram avaliados: matéria seca, teor de carboidratos totais e percentagem de sobrevivência de mudas. Foram utilizadas as cultivares IAC-Campinas, Pelican e IAC-Guarani. Foi utilizado o delineamento experimental em esquema fatorial 3x2 (três cultivares e dois sistemas de produção de mudas), com três repetições. As mudas produzidas em vasos suspensos apresentaram maior percentagem de sobrevivência e maiores teores de carboidratos totais. O segundo e terceiro experimentos tiveram como objetivo avaliar o uso da técnica de frigoconservação em mudas produzidas no sistema de vasos suspensos. As mudas foram acondicionadas em sacos de polietileno e frigoconservadas durante 120 dias em uma B.O.D. a -1 + 1oC. Foram então retiradas da câmara fria e plantadas em bandejas de poliestireno expandido de 128 células preenchidas com vermiculita. As bandejas foram colocadas em uma câmara nebulizadora, onde permaneceram por 21 dias para enraizamento. Em seguida foram transplantadas para vasos de 250ml e levadas para casa de vegetação. Foi avaliada a percentagem de sobrevivência das mudas. No segundo experimento utilizou-se o delineamento experimental inteiramente ao acaso com cinco cultivares (IAC-Campinas, Dover, Pelican, Sequoia e Sweet Charlie) e nove repetições. No terceiro experimento foi utilizado o esquema fatorial 5x2 (cinco cultivares: IAC-Campinas, Oso Grande, Camarosa, Dover e Sweet Charlie; e dois tratamentos de enraizamento: com e sem ácido indol butírico) com quatro repetições. O sistema de frigoconservação adotado apresenou desempenho insatisfatório devido à baixa percentagem de sobrevivência das mudas. O quarto experimento estudou o efeito da vernalização em mudas de cinco cultivares de morangueiro produzidas no sistema de vasos suspensos. As mudas foram plantadas em vasos de 250 ml, preenchidos com substrato formulado com areia e vermiculita (4:1) e mantidas em casa de vegetação durante seis meses. O delineamento experimental utilizado foi o fatorial 5x2, com cinco cultivares (IAC-Campinas, Dover, Sweet Charlie, Cartuno e Oso Grande) com e sem vernalização das mudas, com quatro repetições. Para vernalização, as mudas foram levadas para câmara fria, à temperatura de 10 + 2ºC, e fotoperíodo de 10 h de luz/dia, durante 28 dias. Em seguida, foram transplantadas para dois locais de cultivo com características climáticas distintas, Piracicaba,SP e Caldas,MG. Foram avaliadas as percentagens de sobrevivência, florescimento, frutificação e emissão de estolhos e o peso da matéria fresca e número de frutos produzidos por planta. A sobrevivência de mudas não foi afetada pela vernalização em nenhuma das localidades. Houve efeito significativo no florescimento e na frutificação das plantas vernalizadas apenas em Piracicaba. O estolonamento de plantas foi mais precoce em Piracicaba. Para todas as cultivares a produção de frutos foi e insignificante e comercialmente inviável em ambas as localidades. / With the objective of studying the runners production system in suspended pots under protected cultivation and the application of techniques of stored cold and vernalization of runners produced by this system, four experiments were conducted in the Department of Crop Production, ESALQ, Piracicaba, SP-Brazil. In the first experiment it was compared the conventional strawberry runners production system with the runner production system in suspended pots. For that, it was measured the dry matter and carbohydrates contents in runners and the survival percentage when the runner were transplanted to field production areas. The cultivars IAC-Campinas, Pelican and IAC-Guarani were used, in an experimental design of factorial arrangement 3x2 (three cultivars and two runners production systems), three replications. The runners produced by the system of suspended pots accumulated higher amount of total carbohydrates and the plant survival rate. The second and third experiments had the objective of evaluating the use of a technique of storage cold in runners produced in the system of suspended pots. After the selection, the runners were conditioned in polyethylene bags and storage cold conditions for 120 days in a B.O.D. at -1+1ºC. After that they were removed of the cold camera and planted in trays of expanded polystyrene of 128 cells with vermiculite. The trays were put in a spray chamber 21 days for rooting. After that hey were transplanted to pots of 250mL and then placed in the greenhouse. It was evaluated the percentage of runners survival. In the second experiment it was used the experimental entirely random design, five strawberry cultivars (IAC-Campinas, Dover, Pelican, Sequoia and Sweet Charlie), and nine repetitions. In the threat experiment the factorial outline used was 5x2 (five cultivars: IAC-Campinas, Big Oso, Camarosa, Dover and Sweet Charlie; and two treatments: with and without indol butyric acid) with four repetitions. The storage cold of strawberry runners produced in system of suspended pots lower percentage of survival of seedlings in the two experiments. Therefore, the system of storage cold was not compatible with the type of storage runners. The fourth experiment had the objective of studying the effect of the runner vernalization of five strawberry cultivars produced in suspended pot system. In order to have availability of strawberry runners during the off season, they were planted in pots of 250 mL, filled out with substrate formulated with sand and vermiculite (4:1) and kept in the greenhouse for six months. Completely randomized blocks with the factorial design 5x2, with five strawberry cultivars (IAC-Campinas, Dover, Sweet Charlie, Cartuno and Big Oso) and two treatments (with and without strawberry runners vernalization). For vernalization, the strawberry runners were taken from cold camera to the temperature of 10 + 2ºC, and fotoperiod of 10 h of light/day for 28 days. After that, they were transplanted for two cultivation places with different climatic conditions, Piracicaba/SP and Caldas/MG. They were analyzed the survival percentages, flower blooming, fructification and emission of stolons and the weight and number of fruits produced by plant. The strawberry runners survival was not affected by the vernalization in none of the places. There were only significant effect on flower appearance and fructification of the vernalized plants, only in Piracicaba. The runner emitions were earlier in Piracicaba. For all strawberry cultivars the production of fruits was very low and the produced fruits were unsuitable for commercialization in both places.
30

The molecular genotyping of flower development genes and allelic variations in ‘historic’ barley accessions

Aslan, Selcuk January 2010 (has links)
<p>This is a genetic study of flowering time in cultivated barley with the aim to identify the alleles contributing to rapid flowering and frost resistance. We have genotyped a collection of 23 historic barley varieties for the crucial genes [<em>VRN-1, VRN-2, VRN-3</em> (<em>HvFT</em>), <em>Ppd-H1, CO</em>, and <em>Vrs1</em>]. We have amplified the polymorphic mutations by PCR-based methods, and sequenced them to identify possible haplotype groups. The row type was not determined of all accessions, but all the Scandinavian varieties were found to carry mutant alleles of <em>Vrs1</em>, that indicates them to be six-row barleys. The deletion of the crucial segment of <em>VRN-1 </em>vernalization contributes dominant spring growth habit. We found haplotype groups 2 and 4 to be dominant in Northern barleys whereas haplotype groups 1 and 5 dominated in south. The presence of dominant allele <em>VRN-2</em> gene is addressed to floral repression until plants get vernalized. Most of the 23 varieties were found to have deleted allele of <em>VRN-2</em>, which is connected with a spring growth habit. The only four of the accessions that have the dominant allele of <em>Ppd-H1</em> that contribute flowering are generally from the south of Europe. <em>HvFT</em> and <em>CO</em> genes <em>CO</em>-interact to influence flowering time. <em>CO</em> haplotype grouping suggest a geographical distribution of different alleles but needs more disseminations. Certain <em>HvFT</em> alleles cause extremely early flowering during apex development in the varieties that have deletion of <em>VRN-2</em> alleles under long days. <em>VRN-3</em> alleles of 14 varieties were identified.</p>

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