test
Search publications, data, projects and authors

Thesis

Spanish

ID: <

http://hdl.handle.net/10251/86205

>

·

DOI: <

10.4995/thesis/10251/86205

>

Where these data come from
Taking advantage of diversity in Solanum L. section Lycopersicon for the genetic improvement of organoleptic quality in tomatoes

Abstract

Many modern tomato cultivars, in general, do not satisfy the organoleptic expectations of the consumers, as among the selection criteria used, the organoleptic quality has not been prioritized. However, the growing disappointment of consumers with this aspect has placed organoleptic quality as an important breeding objective. The present thesis aims to contribute to fulfil this objective, using the natural variability present in the genus Solanum section Lycopersicon to increase the content in compounds involved in the perception by the taste. Initially, a capillary zone electrophoresis method has been optimized, allowing the simultaneous quantification of organic acids such as oxalic, malic and citric acids and sugars such as glucose, fructose and sucrose, which determine, to a greater extent, the taste perception in tomatoes, with limits Of detection below 2 and 25 ¿g ml -1 respectively. Its high automation and reproducibility, as well as its simple sample preparation, running time of less than 20 minutes and a low execution cost, have enables its use in the evaluation of organoleptic quality in tomato germplasm. Next, accessions and non-bred varieties of cultivated tomato of different origins, as well as wild and wild-related entries (Solanum lycopersicum, S. pimpinellifolium, S. habrochaites, S. pennellii and S. peruvianum) have been evaluated in order to detect sources of variability potentially useful in breeding programs. Among the materials evaluated there is great variability and very high contents in compounds responsible for tomato taste. Accessions from the Lycopersicon group have been identified, which include the phylogenetically closest wild species to the crop, which nearly triple the contents of sugars and malic acid and double that of citric acid of the commercial varieties taken as control. These accessions will facilitate breeding programs targeted to balanced increases of taste. Although more phylogenetically distant, two accessions of S. habrochaites, from the Eriopersicon group, with malic and citric acid contents seven and nine times greater than the best of controls have been identified, which may be useful when looking for materials with shades of acidic taste. Finally, since the environment can influence directly or through the interaction of genotype x environment the accumulation of these compounds, a multi-environment study has been developed as a tool to evaluate the real genetic potential of various accessions for the improvement of taste tomato. In this study, we have evaluated clonal replicates in three different environments to more accurately estimate the contribution of the environment, genotype and genotype x environment interaction. The effect of the environment has been estimated from the contribution to the accumulation of these compounds of the photosynthetically active radiation and the temperature, observing that the radiation affects to a greater degree the content in sugars and the temperature to the accumulation of acids. With the predictions of genotypic contribution and genotype x environment interaction, two accessions have been identified, one of S. habrocahites and another of S. pimipinellifolium, which may be interesting as sources of variability to increase taste with acid hue for its high Content of malic and citric acids and their stability. The identification of materials with different accumulation profiles of citric, malic and glutamic acids will also be useful in the study of the regulation of the cycles of tricarboxylic acids and GABA shunt. On the other hand, it has been concluded that in order to take advantage of the intra-population variation it will be necessary to evaluate a large number of plants. TESIS

Your Feedback

Please give us your feedback and help us make GoTriple better.
Fill in our satisfaction questionnaire and tell us what you like about GoTriple!