European Vintage tomatoes galore: a result of farmers combinatorial assorting/swapping of a few diversity rich loci

TitleEuropean Vintage tomatoes galore: a result of farmers combinatorial assorting/swapping of a few diversity rich loci
Publication TypeArticolo su Rivista peer-reviewed
Year of Publication2021
AuthorsBlanca, Jose, Pons Clara, Montero-Pau Javier, Sanchez-Matarredona David, Ziarsolo Peio, Fontanet Lilian, Fisher Josef, Plazas Mariola, Casals Joan, Rambla Jose Luis, Riccini Alessandro, Pombarelli Samuela, Ruggiero Alessandra, Sulli Maria, Grillo Stephania, Kanellis Angelos, Giuliano Giovanni, Finkers Richard, Cammareri Maria, Grandillo Silvana, Mazzucato Andrea, Causse Mathilde, Díez Maria José, Prohens Jaime, Zamir Dani, Cañizares Joaquin, Monforte Antonio Jose, and Granell Antonio

A comprehensive collection of 1,254 tomato accessions corresponding to European heirlooms and landraces, together with modern varieties, early domesticates and wild relatives, were analyzed by genotyping by sequencing. A continuous genetic gradient between the vintage and modern varieties was observed. European vintage tomatoes displayed very low genetic diversity, with only 298 loci out of 64,943 variants being polymorphic at the 95% threshold. European vintage tomatoes could be classified in several genetic groups. Two main clusters consisting of Spanish and Italian accessions showed a higher genetic diversity than the rest varieties, suggesting that these regions might be independent secondary centers of diversity and with a different history. Other varieties seem to be the result of a more recent complex pattern of migrations and hybridizations among the European regions. Several polymorphic loci were associated in a GWAS with fruit morphological traits in the European vintage collection, and the corresponding alleles were found to contribute to the distinctive phenotypic characteristic of the genetic varietal groups. The few highly polymorphic loci associated with morphological traits in an otherwise diversity-poor genome suggests a history of balancing selection, in which tomato farmers maintained the morphological variation by applying a high selective pressure within different varietal types.Highlight The high phenotypic diversity observed among European vintage varieties was created by traditional farmers by combining very few polymorphic loci subjected to balancing selection.Competing Interest StatementThe authors have declared no competing interest.GBSGenotyping by SequencingGWASGenome-Wide Association AnalysisLDLinkage DisequilibriumLSLLong Shelf-LifeMAFMinimum Allele FrequencyPcoAPrincipal Coordinate AnalysesQTLQuantitative Trait LocusSLLSolanum lycopersicum L. var. lycopersicumSLCS. lycopersicum var. cerasiformeSNPSingle Nucleotide PolymorphismSPS. pimpinellifolium