hide
Free keywords:
genome wide association, soluble solids, tomato yield
Abstract:
SUMMARY Tomato is a prominent fruit and vegetable with rich genetic resources for the improvement of the crop. By using a phenotype-guided screen of an excess of 7900 tomato accessions from around the world we identified new associations for complex traits such as fruit weight and total soluble solids (Brix). Here, we present the phenotypic data on several years of trials. To illustrate the power of this dataset we use two case studies. First, evaluation of colour revealed allelic variation in phytoene synthase 1 that resulted in differently coloured or even bi-coloured fruit. Secondly, in view of the negative relationship between fruit weight and Brix we preselected a subset of the collection that includes high and low Brix values in each category of fruit sizes. Genome wide association analysis allowed us to detect novel loci associated with total soluble solid content and fruit weight. In addition, we developed eight F2 biparental intraspecific populations. Furthermore, by taking a phenotype guided approach we were able to isolate individuals with high Brix that were not compromised in terms of yield. In addition, the demonstration of novel results despite the high number of previous genome wide association studies of these traits in tomato suggests that adoption of a phenotype-guided pre-selection of germplasm may represent a general strategy for finding target genes for breeding.
