Estudios sobre regeneración y transformación genética en pepino (Cucumis sativus L) vía Agrobacterium tumefaciens
Cucumber is one of the most important horticultural species at economic level. Despite its agronomic relevance, there is currently no efficient transformation method available. The problems to obtain transgenic cucumber plants are mainly due to the low morphogenetic response in explants of certain g...
| Autor: | |
|---|---|
| Tipo de recurso: | tesis doctoral |
| Fecha de publicación: | 2017 |
| País: | España |
| Institución: | Universitat Politècnica de València (UPV) |
| Repositorio: | RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia |
| Idioma: | español |
| OAI Identifier: | oai:riunet.upv.es:10251/90405 |
| Acceso en línea: | https://riunet.upv.es/handle/10251/90405 |
| Access Level: | acceso abierto |
| Palabra clave: | pepino Cucumis sativus L. regeneración de plantas morfogénesis transformación genética Agrobacterium tumefaciens GENETICA |
| Sumario: | Cucumber is one of the most important horticultural species at economic level. Despite its agronomic relevance, there is currently no efficient transformation method available. The problems to obtain transgenic cucumber plants are mainly due to the low morphogenetic response in explants of certain genotypes, poor adequacy of selection methods, decrease in regeneration rate as a consequence of the usual treatments in a transformation experiment and, above all, the high rate of 'escape' plants. Taking into account the existing problems, the first objective of the present work has been the evaluation of the morphogenetic response in cucumber explants and the development of regeneration methods potentially useful in transformation experiments. These studies have been carried out with two commercial cultivars, four pure lines and one line that has been frequently used in cucumber breeding programs. Different types of primary explants have been evaluated to determine which may be the most suitable in a transformation experiment. The influence of the ontogenic state of the seedling on the degree of myxoploidy in cotyledon explants has been studied. Likewise, the ploidy level of regenerated plants from these explants has been determined. Regarding the culture medium, the effect of growth regulators, as well as that of other components, such as silver nitrate or copper sulphate, has been studied. In the context of the second objective, studies on the different stages of the transformation process by co-cultivation of cucumber explants with Agrobacterium tumefaciens have been carried out. Several factors, such as the Agrobacterium strain, how to carry out the phases of inoculation and co-culture, the suitability of different marker genes in the selection process and the influence of different components of the culture medium have been analyzed. Attempts have also been made to infer the causes of the occurrence of 'escape' plants or the formation of chimeras in cucumber transformation experiments. Finally, based on the results obtained, some solutions that could help to avoid this problem in future experiments are proposed. |
|---|