18-BTT: Epi-TOM: The development and characterization of an EpiRIL TOMato population

点击翻译按钮获取中文摘要

Tomato (Solanum lycopersicum) is the most important commercial fruit crop in the world with an estimated global net production value well in excess of $50bn [www.fao.org]. On the basis of volume consumed (fresh and processed) tomato products play a crucial role in the human diet, providing essential minerals, vitamins and health promoting bioactive phytochemicals. Presently Marker Assisted Selection (MAS) has been the method of choice to deliver new varieties/hybrids with improved consumer and agronomic traits. MAS is reliant on the exploitation of natural variation. However, it has become apparent that in many crop species including tomato, phenotypic diversity is higher than that expected based on the available genetic variation alone. One explanation for this phenomena is the emerging evidence in plant species that stable inherited epigenetic variation can provide a basis for Darwinian evolution independent of DNA sequence changes.Using the model plant Arabidopsis, genetically identical recombinant inbred lines harbouring mosaics of methylation (epiRILs) have been created. This has been achieved by crossing two genetically identical lines with the exception that one of the parents is impaired in DNA methyltransferase MET1, a gene required for propagating cytosine methylation during DNA replication. In subsequent generations mosaics of methylation are fixed by self-pollination and single seed descent to F8. a unique epiRIL population in tomato of near homozygous lines with respect to their epigenomes, which will form the foundation of the current project and provide a valuable genetic/chemical community resource. The population consists of 115 lines. To date observable phenotypic differences are evident within the population (e.g. plant height and fruit size) However, the extent of chemical variation linked to consumer and agronomic traits awaits assessment within the remit of the proposed epi-TOM project. The project will deliver important information on the role of epigenetic variation on chemo/phenotypes in a complex genome, which can be exploited for the elucidation of novel quantitative traits with an epigenetic basis (epi-QTL).