The peach genome and its breeding applications

Almost a decade after the publication of the genome of a double-haploid genotype from the 'Lovell' peach rootstock, knowledge on the peach and other Prunus genetics has enormously increased, and its applications for breeding have been pushed further forward. Currently there are 29 Prunus de novo sequences available in the genome database for Rosaceae, additionally showing the already known high synteny between all Prunus genomes. More than 60 Prunus major genes, mostly from peach or peach x almond crosses, have been identified, mapped and some of them cloned or have strong candidates responsible for their phenotypic variation. Marker-assisted selection has been integrated as an efficient approach to help breeders, based on the development of tightly linked markers to the genes involved in main characters under selection. New marker-based breeding approaches have been proposed: marker-assisted introgression, for fast introgression of new alleles or genes coming from exotic sources, that has already been successfully implemented. Resynthesis, a strategy to obtain peach lines that, maintaining the basic trait architecture of a top cultivar, can integrate new alleles or genes of interest with non-transgenic approaches, is underway. New tools for phenotypic and genetic analysis have recently been developed, including a multi-site peach reference population (RefPop) and a complete collection of peachalmond introgression lines. Together, they promise a deeper understanding of peach genetics, with the expected consequences of increased peach fruit quality, productivity, and resilience to the potentially devastating effects of climate change.