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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.
1

The in vitro manipulation of cauliflower (Brassica oleracea L. convar. botrytis (L.) Alef. var. botrytis L.) meristematic tissues for utilisation in genetic improvement programmes

Kieffer, Martin Louis January 1996 (has links)
Cauliflower curd meristem activity (organogenic, plastochronic, phyllotactic) was analysed biometrically and confirmed that the curd is the product of a constant process of meristem production and branch ramification with little if any dominance between branch apices. A growth model based on curd branching pattern was developed and its mathematical expression enabled the estimation of the number of meristems carried by a curd at maturity to be over ten million which was previously widely underestimated. Analysis of the response to the in vitro culture of this meristematic tissues revealed that meristems are not predetermined to produce flower and that their shoot regeneration capacity is under several levels of control, the most important being explant physical property (size) and the culture system (nutrient supply). Optimisation of these parameters enabled the development of a low cost, semi-automated protocol for mass production of cauliflower propagules at an unprecedented scale with over 10000 propagules produced per curd. Micropropagules a few millimetres in length were produced, encapsulated in calcium alginate hydrogel, stored at 4°C for several months and used as an 'artificial seed' system of cauliflower propagation. The response to the procedure of micropropagule production is genotype-dependent with summer heading varieties being less reactive than winter heading varieties, this phenomenon was also associated with plasmalemma instability at the cellular (protoplast) level. Furthermore, this material was successfully cryopreserved in liquid nitrogen using a dehydration / vitrification method. The micropropagation protocol is of great interest when used as a regeneration system for experiments involving genetic manipulation such as genetic transformation. A preliminary study of genetic transformation by microprojectile bombardment, using the gus reporter gene, allowed transient expression in curd meristematic tissue. The fundamental and industrial implications for cauliflower breeding of the different protocols developed in this thesis are discussed.
2

Capacidade de combinação de linhagens de pepino (Cucumis sativus L.) do grupo japonês

Gadum, Juliana [UNESP] 25 January 2005 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-01-25Bitstream added on 2014-06-13T19:43:11Z : No. of bitstreams: 1 gadum_j_dr_botfca.pdf: 288776 bytes, checksum: 8e26883c5c77307d1127daa626385ae9 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Esse trabalho teve como objetivo estimar a capacidade geral e específica de combinação, empregando-se um topcross entre linhagens e populações de pepino japonês. Foram obtidos 16 híbridos experimentais a partir de 2 populações testadoras (geração F2 de Yoshinari e de Natsusuzumi) e 8 linhagens S5 obtidas a partir do híbrido comercial Hokuho, também foi avaliado o híbrido F1 Hokuho, totalizando 27 tratamentos. O delineamento experimental utilizado foi em blocos casualizados com 4 repetições e cada parcela foi constituída de 4 plantas. Foram realizados dois experimentos em duas épocas, onde foram avaliadas as seguintes características relacionadas ao crescimento vegetativo da planta: comprimento das plantas, número de folhas, número de nós, número de brotações laterais e porcentagem de brotações. Também se avaliou o peso de frutos totais, peso de frutos comerciais, número total de frutos, número de frutos comerciais, porcentagem de frutos comerciais e peso médio de frutos comerciais. As análises de capacidades combinatória foram efetuadas de acordo com o modelo de Geraldi & Miranda Filho (1988). A população de Yoshinari (TY) apresentou, em média, melhor capacidade de se combinar com as linhagens de Hokuho. A linhagem L7 apresentou os maiores valores positivos da estimativa da CGC para a maioria das características avaliadas nos dois experimentos e os híbridos H1Y e H1N, que continham a linhagem L1 como parental, foram os que apresentaram maiores valores para a estimativa da CEC com as populações testadoras para a maioria das características avaliadas nos dois experimentos realizados, enquanto os que tinham a linhagem L5 como parental apresentaram os menores valores. Conclui-se, portanto, que há um alto potencial de se extrair linhagens de Yoshinari para cruzamentos com linhagens de Hokuho, a fim de se obter híbridos tão bons quanto o Hokuho. / The objective of the present work was obtain general and specific combining ability estimates, using a top cross between lines and japanese cucumber populations. It was obtained 16 experimental hybrids starting from 2 test populations (Yoshinari and Natsusuzumi) and 8 S5 lines obtained starting from the Hokuho commercial hybrid. The Hokuho hybrid F1 was also evaluated, totaling 27 treatments. The experimental design used was randomized block with four replications and for plant per plot. Were evaluated the following characteristics related to the vegetative growth of the plant: length of the plants, number of leaves, number of us, number of lateral produce and produce percentage. Related to the production it was evaluated: weight of total fruits, weight of commercial fruits, total number of fruits, number of commercial fruits, percentage of commercial fruits and weigh medium of commercial fruits. The analyses of combining ability were evaluated in agreement with the model of Geraldi & Miranda Filho (1988). The Yoshinari of population (TY) presented, on average, better combining ability with the lines of Hokuho, the lines L7 presented the largest positive values of gi for most of the evaluated characteristics in the two experiments and hybrids with the lines L1 it was the one that it presented larger values for CEC with the test populations for most of the evaluated characteristics in the two accomplished experiments, while the hybrids of lines L5 showed the smallest values. It is ended that there is a high potential of extracting lines of Yoshinari for crossings with lines of Hokuho, in order to obtain hybrid as good as Hokuho, with the advantage of being adapted to national conditions.
3

Capacidade de combinação de linhagens de pepino (Cucumis sativus L.) do grupo japonês /

Gadum, Juliana, 1976- January 2005 (has links)
Orientador: Antonio Ismael Inácio Cardoso / Banca: Norberto da Silva / Banca: Maurício Dutra Zanotto / Banca: Paulo Cesar Tavares de Melo / Banca: Wilson Roberto Maluf / Resumo: Esse trabalho teve como objetivo estimar a capacidade geral e específica de combinação, empregando-se um "topcross" entre linhagens e populações de pepino japonês. Foram obtidos 16 híbridos experimentais a partir de 2 populações testadoras (geração F2 de Yoshinari e de Natsusuzumi) e 8 linhagens S5 obtidas a partir do híbrido comercial Hokuho, também foi avaliado o híbrido F1 Hokuho, totalizando 27 tratamentos. O delineamento experimental utilizado foi em blocos casualizados com 4 repetições e cada parcela foi constituída de 4 plantas. Foram realizados dois experimentos em duas épocas, onde foram avaliadas as seguintes características relacionadas ao crescimento vegetativo da planta: comprimento das plantas, número de folhas, número de nós, número de brotações laterais e porcentagem de brotações. Também se avaliou o peso de frutos totais, peso de frutos comerciais, número total de frutos, número de frutos comerciais, porcentagem de frutos comerciais e peso médio de frutos comerciais. As análises de capacidades combinatória foram efetuadas de acordo com o modelo de Geraldi & Miranda Filho (1988). A população de Yoshinari (TY) apresentou, em média, melhor capacidade de se combinar com as linhagens de Hokuho. A linhagem L7 apresentou os maiores valores positivos da estimativa da CGC para a maioria das características avaliadas nos dois experimentos e os híbridos H1Y e H1N, que continham a linhagem L1 como parental, foram os que apresentaram maiores valores para a estimativa da CEC com as populações testadoras para a maioria das características avaliadas nos dois experimentos realizados, enquanto os que tinham a linhagem L5 como parental apresentaram os menores valores. Conclui-se, portanto, que há um alto potencial de se extrair linhagens de Yoshinari para cruzamentos com linhagens de Hokuho, a fim de se obter híbridos tão bons quanto o Hokuho. / Abstract: The objective of the present work was obtain general and specific combining ability estimates, using a top cross between lines and japanese cucumber populations. It was obtained 16 experimental hybrids starting from 2 test populations (Yoshinari and Natsusuzumi) and 8 S5 lines obtained starting from the Hokuho commercial hybrid. The Hokuho hybrid F1 was also evaluated, totaling 27 treatments. The experimental design used was randomized block with four replications and for plant per plot. Were evaluated the following characteristics related to the vegetative growth of the plant: length of the plants, number of leaves, number of us, number of lateral produce and produce percentage. Related to the production it was evaluated: weight of total fruits, weight of commercial fruits, total number of fruits, number of commercial fruits, percentage of commercial fruits and weigh medium of commercial fruits. The analyses of combining ability were evaluated in agreement with the model of Geraldi & Miranda Filho (1988). The Yoshinari of population (TY) presented, on average, better combining ability with the lines of Hokuho, the lines L7 presented the largest positive values of gi for most of the evaluated characteristics in the two experiments and hybrids with the lines L1 it was the one that it presented larger values for CEC with the test populations for most of the evaluated characteristics in the two accomplished experiments, while the hybrids of lines L5 showed the smallest values. It is ended that there is a high potential of extracting lines of Yoshinari for crossings with lines of Hokuho, in order to obtain hybrid as good as Hokuho, with the advantage of being adapted to national conditions. / Doutor
4

Herança de características morfológicas e agronômicas do cruzamento intraespecífico entre couve-flor e couve-brócolo

Zatarim, Mariana [UNESP] 15 February 2005 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-02-15Bitstream added on 2014-06-13T20:03:57Z : No. of bitstreams: 1 zatarim_m_dr_botfca.pdf: 715464 bytes, checksum: dbf6d20b9b3a33bda1fe90a7ff22c799 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Com objetivo de estudar a herança de características morfológicas e agronômicas em populações progenitoras e diferentes gerações obtidas do cruzamento entre couve-flor e couve-brócolo, foram cruzadas a linhagem de couve-flor de verão Piracicaba Precoce com o híbrido de couve-brócolo de cabeça única, denominado Legacy, obtendo-se as gerações F1 e F2, e os retrocruzamentos para ambas as populações progenitoras. Realizaram-se dois experimentos, denominados de outono-inverno e verão-outono, respectivamente, em 2002 e 2004, na Fazenda Experimental São Manuel, pertencente a Faculdade de Ciências Agronômicas, Campus de Botucatu/UNESP, localizada no município de São Manuel/SP. Utilizou-se o delineamento experimental de blocos ao acaso, com quatro repetições. Os seis tratamentos, constituídos da couve-flor linhagem L-8995-5, da couve-brócolo híbrida Legacy, das gerações F1 e F2, e retrocruzamentos para ambos os progenitores, foram plantados em parcelas de 20 plantas. A geração F2 foi representada por quatro parcelas, as gerações de retrocruzamentos por duas parcelas e os progenitores por uma parcela, as quais foram distribuídas ao acaso dentro de cada bloco. O plantio no campo foi realizado em linhas duplas espaçadas de 0,8 m x 1,0 m e 0,7 m entre plantas dentro da fileira. As avaliações foram feitas antes e durante a colheita das inflorescências, individualmente para todas as plantas da parcela, com exceção do número de folhas. As características avaliadas foram: início de formação da inflorescência (número de dias da semeadura até o aparecimento visual da inflorescência), ciclo (número de dias da semeadura à colheita da inflorescência no ponto comercial), altura de planta (medida do nível do solo até o ápice da inflorescência, somente para o experimento de verão-outono), peso da inflorescência, diâmetro da inflorescência... / With objective of studying the inheritance of morphologic and agronomic characteristics in populations progenitors and different generations obtained of crossing among cauliflower and broccoli, the lineage of summer cauliflower Precocious Piracicaba with the hybrid of broccoli unique head, denominated Legacy were crossed being obtained the generations F1 and F2, and the recrossing for both progenitors populations . Two experiments were accomplished denominated of fall-winter and summer-fall, respectively, in 2002 and 2004, in the São Manuel Experimental Farm, belonging to the Agronomic Science College, Campus of Botucatu/UNESP, located in the municipal district of São Manuel/SP. The randomized blocks design was used with four replications. The six treatments, constituted of the cauliflower lineage L-8995-5, the hybrid broccoli hybrid Legacy, the generations F1 and F2, and retrocrossings for both progenitors, were planted in portions of 20 plants. The generation F2 was represented by four portions, the retrocrossings generations for two portions and the progenitors for a portion, which were distributed in random inside of each block. The planting in the field was accomplished in spaced double lines of 0,8 m x 1,0 m and 0,7 m among plants inside of the array. The evaluations were accomplished before and during the harvest of the flowers, individually for all the plants of the portion, except for the number of leaves. The characteristics evaluated were: beginning of formation of the group of flowers (number of days from the planting to the visual emergence of the group of flowers), cycle (number of days from the planting to the harvest of the group of flowers at commercial point), plant height (measurement of the level of the soil to the apex of the flowers, only for the summer-fall experiment), weigh, diameter of the flowers...(Complete abstract click electronic access below)
5

Herança de características morfológicas e agronômicas do cruzamento intraespecífico entre couve-flor e couve-brócolo /

Zatarim, Mariana. January 2005 (has links)
Orientador: Norberto da Silva / Banca: Francisco Luiz Araújo Câmara / Banca: Antonio Ismael Inácio Cardoso / Banca: Aniello A. Cutolo Filho / Banca: Keigo Minami / Resumo: Com objetivo de estudar a herança de características morfológicas e agronômicas em populações progenitoras e diferentes gerações obtidas do cruzamento entre couve-flor e couve-brócolo, foram cruzadas a linhagem de couve-flor de verão Piracicaba Precoce com o híbrido de couve-brócolo de cabeça única, denominado Legacy, obtendo-se as gerações F1 e F2, e os retrocruzamentos para ambas as populações progenitoras. Realizaram-se dois experimentos, denominados de outono-inverno e verão-outono, respectivamente, em 2002 e 2004, na Fazenda Experimental São Manuel, pertencente a Faculdade de Ciências Agronômicas, Campus de Botucatu/UNESP, localizada no município de São Manuel/SP. Utilizou-se o delineamento experimental de blocos ao acaso, com quatro repetições. Os seis tratamentos, constituídos da couve-flor linhagem L-8995-5, da couve-brócolo híbrida Legacy, das gerações F1 e F2, e retrocruzamentos para ambos os progenitores, foram plantados em parcelas de 20 plantas. A geração F2 foi representada por quatro parcelas, as gerações de retrocruzamentos por duas parcelas e os progenitores por uma parcela, as quais foram distribuídas ao acaso dentro de cada bloco. O plantio no campo foi realizado em linhas duplas espaçadas de 0,8 m x 1,0 m e 0,7 m entre plantas dentro da fileira. As avaliações foram feitas antes e durante a colheita das inflorescências, individualmente para todas as plantas da parcela, com exceção do número de folhas. As características avaliadas foram: início de formação da inflorescência (número de dias da semeadura até o aparecimento visual da inflorescência), ciclo (número de dias da semeadura à colheita da inflorescência no ponto comercial), altura de planta (medida do nível do solo até o ápice da inflorescência, somente para o experimento de verão-outono), peso da inflorescência, diâmetro da inflorescência...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: With objective of studying the inheritance of morphologic and agronomic characteristics in populations progenitors and different generations obtained of crossing among cauliflower and broccoli, the lineage of summer cauliflower Precocious Piracicaba with the hybrid of broccoli unique head, denominated Legacy were crossed being obtained the generations F1 and F2, and the recrossing for both progenitors populations . Two experiments were accomplished denominated of fall-winter and summer-fall, respectively, in 2002 and 2004, in the São Manuel Experimental Farm, belonging to the Agronomic Science College, Campus of Botucatu/UNESP, located in the municipal district of São Manuel/SP. The randomized blocks design was used with four replications. The six treatments, constituted of the cauliflower lineage L-8995-5, the hybrid broccoli hybrid Legacy, the generations F1 and F2, and retrocrossings for both progenitors, were planted in portions of 20 plants. The generation F2 was represented by four portions, the retrocrossings generations for two portions and the progenitors for a portion, which were distributed in random inside of each block. The planting in the field was accomplished in spaced double lines of 0,8 m x 1,0 m and 0,7 m among plants inside of the array. The evaluations were accomplished before and during the harvest of the flowers, individually for all the plants of the portion, except for the number of leaves. The characteristics evaluated were: beginning of formation of the group of flowers (number of days from the planting to the visual emergence of the group of flowers), cycle (number of days from the planting to the harvest of the group of flowers at commercial point), plant height (measurement of the level of the soil to the apex of the flowers, only for the summer-fall experiment), weigh, diameter of the flowers...(Complete abstract click electronic access below) / Doutor
6

Breeding an open pollinated broccoli for organic production systems using participatory methods

McKenzie, Laurie R. 06 March 2013 (has links)
Organic agriculture is an important and growing sector of U.S. and world food production. Consumers are increasingly aware of and interested in the production practices and impacts associated with agriculture and as such, are showing a preference for sustainably produced, raised, and harvested foods. In order to continue to meet the growing demand for organic produce, organic growers need cultivars that are optimally adapted to organic and low input conditions. Quality seed is the foundation of any functional and stable farming system. Unfortunately the lack of organically bred and produced seed is hindering the continued growth and success of organic farming. Meeting the needs of the organic sector has been a challenge for the seed industry; it is an industry that often doesn't understand the specific and unique requirements associated with the diversity of environmental and market demands of organic systems. However, organic farmers and the organic food systems they supply, require a robust organic seed system that is appropriately adapted to regional agronomic challenges and market needs, meets standards and regulations, and encompasses the social and ecological values of organic agriculture. One plausible approach to meeting the cultivar and seed needs of organic and low input production systems is through the use of participatory plant breeding (PPB). PPB is a collaborative approach for identifying and developing genetically diverse plant material and varieties involving partnerships among formal sector breeders and researchers, farmers, extension agents, educators, and end users. Participatory plant breeding fundamentally changes the way that formal breeding programs and farmers manage germplasm and plant genetic resources. Typically, formal breeding programs restrict access to germplasm and breeding materials and only supply farmers with finished varieties. In PPB, farmers are involved in the early stages of creation and evaluation of germplasm and breeding material, and stay engaged with the breeding process until new varieties are created. PPB is an excellent model for breeding specifically for organic systems because organic systems in developed countries have many similarities to low-input agricultural systems in the developing world. Some of these parallels include heterogeneous growing environments, a wide range of end uses and marketing strategies, lack of suitably adapted and/or derived varieties, lack of attention from the formal seed sector, and a reduced reliance on synthetic inputs (compared to conventional systems). Breeding for organic systems is a relatively young field and breeders in the formal sector do not have a good handle on what traits are important for robust production under organic conditions. Thus the opportunity to meld farmers' experience and knowledge with breeders' expertise is an effective way to breed for organic production systems. The purpose of this project was to investigate and explore the opportunities and challenges of organic plant breeding using participatory research methods. This research had three goals: 1) to develop an open pollinated broccoli with contemporary quality traits for organic production systems using participatory strategies; 2) to compare broccoli selections made by formally trained plant breeders and farmer breeders; and 3) to capture the stories and experiences of the formal breeders and farmer breeders involved with this broccoli material in order to contribute to the growing wealth of knowledge on collaborative and organic breeding work. The Oregon State University Vegetable Breeding Program made significant progress towards decreasing the variability of the broccoli project material through three successive years of modified half-sibling selections. Evaluations and selections were based more strongly on quality traits rather than soley on production traits such as yield. Although progress was incremental and statistically verified in only three out of the fifteen quality traits, we observed trends in the data indicating progress towards an increasingly uniform, stable, and reliable open pollinated broccoli with specific adaptation for organic production systems. There were very few differences between broccoli materials developed by formally trained plant breeders and farmer breeders. This was especially true for the three cultivars developed in the Pacific Northwest (PNW) (one in Washington and two in Oregon). The 'East Coast' population, which had been collaboratively selected by formal and farmer breeders in New York, expressed significantly distinct differences from the PNW materials. When the farmer breeder and formal breeder materials were pooled together and compared to pooled check cultivars they expressed significant differences for nearly all traits across all years. This demonstrated that all of the collaboratively developed open pollinated materials are distinctly different from the F1 hybrids currently available. Our work has demonstrated a few of the myriad of positive outcomes achievable with the use of participatory plant breeding for organic production systems. The participatory nature of this project resulted in increased confidence and feelings of empowerment for all involved. Both farmers and breeders felt their involvement was socially beneficial and widened their networking and seed community circles. The farmer-bred cultivar 'Solstice' is now available as a result of Jonathan Spero's work, and a cultivar tentatively named 'Benton' is about to be released for sale through Oregon State University. Our results agree with previous study findings that formal and farmer breeder selections are often not distinctly different; thus providing evidence for continuing to support the involvement and education of farmers in plant breeding, especially in reference to organic production systems. This study demonstrates the potential of collaboratively developed and farmer-bred cultivars to become viable and vibrant open pollinated alternatives to the current open pollinated cultivars on the market today. / Graduation date: 2013

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