Abstract
Oral Communication Abstract – 5.04 Fruit texture is a complex multi-factorial trait composed by both mechanical and acoustic components, which mainly depend on the modification occurring on the cell wall architecture throughout fruit development and ripening. Both components play a fundamental role in the apple horticultural management, since a favourable mechanical response is essential to guarantee a high postharvest performance, while a valuable acoustic features impact the apple fruit quality acceptance by consumers. To comprehensively decipher the genetic control of fruit texture, two complementing QTL mapping approaches have been carried out in parallel. The first was a pedigree based analysis (PBA) represented by six full-sib families linked by pedigree (416 individuals), while the second was a Genome Wide Association Mapping (GWAS) performed on a cultivar collection (233 accessions). Both plant collections were genotyped with a 20K SNP array, while the phenotype was assessed for two years with a sophisticated texture analyzer. QTL discovery and characterization via PBA was carried out with FlexQTL software (https://www.wageningenur.nl/en/show/FlexQTL.htm), a software developed and improved within the framework of two EU-projects (HiDRAS and FruitBreedomics) and the USDA SCRI project RosBREED. The position and effect of the several genomic loci were performed by the implementation of a Bayesian statistics and Markov chain Monte Carlo simulation, taking into consideration also the IBD (Identity By Descent) of the alleles over the pedigree. This procedure allowed the identification of a set of QTLs distributed over 14 chromosomes out of 17, genetically dissecting the mechanical from the acoustic components. The intervals defined here were moreover validated with a Genome-Wide Association Study. This comparison highlighted an inventory of genomic intervals specifically associated to mechanical and acoustic parameters, respectively, hypothesizing that these sub-traits are effectively