Application of phenotypic, molecular and genomic tools to the identification of tomato candidate genes

Doctoral thesis abstract

Abstract

A tomato (Solanum lycopersicum L.) breeding program must use the knowledge and technology available for the development of efficient strategies to solve different problems in the crop value chain. In this work, we start with four phenotypes of commercial interest: (i) ToCV (Crinivirus) tolerance, (ii) resistance to the herbicide metribuzin, (iii) increase in the vitamin C content and (iv) erect growth habit (erectoid leaf). Applying a working model that integrates different tools at the phenotypic, molecular, and genomic level, we set out to to advance in the identification of candidate genes. The strategy included the following steps: definition of the trait, study of its genetic basis, primary location of the genetic factor in the physical map, identification of candidate genes and genetic validation. The presence of four alleles with a major effect in the described phenotypes was confirmed: cvt, mtz and Vtc and Erl. For cvt and mtz, sufficient information was generated to achieve its primary location. For Vtc, progress was made in the identification of two candidate genes that must be confirmed and validated. Erl was related to a gene not yet characterized, which we call SlTAC1. The applied strategy allowed to advance successfully in the identification of candidate genes, generating information that facilitates the use in tomato breeding of new interest traits. At the same time, new research hypotheses are proposed to complement and deepen the generated knowledge.