RESUMO
Wild tomato species represent a rich gene pool for numerous desirable traits lost during domestication. Here, we exploited an introgression population representing wild desert-adapted species and a domesticated cultivar to establish the genetic basis of gene expression and chemical variation accompanying the transfer of wild-species-associated fruit traits. Transcriptome and metabolome analysis of 580 lines coupled to pathogen sensitivity assays resulted in the identification of genomic loci associated with levels of hundreds of transcripts and metabolites. These associations occurred in hotspots representing coordinated perturbation of metabolic pathways and ripening-related processes. Here, we identify components of the Solanum alkaloid pathway, as well as genes and metabolites involved in pathogen defense and linking fungal resistance with changes in the fruit ripening regulatory network. Our results outline a framework for understanding metabolism and pathogen resistance during tomato fruit ripening and provide insights into key fruit quality traits.
Assuntos
Resistência à Doença/genética , Metaboloma/genética , Solanum lycopersicum/genética , Transcriptoma/genética , Alcaloides/genética , Domesticação , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/parasitologia , Fungos/genética , Fungos/patogenicidade , Regulação da Expressão Gênica de Plantas/genética , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/microbiologia , Redes e Vias Metabólicas/genética , Fenótipo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Solanum/genética , Solanum/microbiologiaRESUMO
We present a resource for fine mapping of traits derived from the wild tomato species Solanum pennellii (LA0716). The population of backcross inbred lines (BILs) is composed of 446 lines derived after a few generations of backcrosses of the wild species with cultivated tomato (cultivar M82; LA3475), followed by more than seven generations of self-pollination. The BILs were genotyped using the 10K SOL-CAP single nucleotide polymorphism (SNP) -Chip, and 3700 polymorphic markers were used to map recombination break points relative to the physical map of Solanum lycopersicum. The BILs carry, on average, 2.7 introgressions per line, with a mean introgression length of 11.7 Mbp. Whereas the classic 76 introgression lines (ILs) partitioned the genome into 106 mapping bins, the BILs generated 633 bins, thereby enhancing the mapping resolution of traits derived from the wild species. We demonstrate the power of the BILs for rapid fine mapping of simple and complex traits derived from the wild tomato species.