WP4 aims to explore genetic diversity in European apple and peach germplasm collections using association genetics. The objectives are to improve knowledge of genetic variability, define subpopulations, identify genomic regions contributing to traits, and supply tightly linked markers to WP1. The approach involves phenotyping over 1900 apple and 1250 peach cultivars, genotyping them with SNPs, analyzing population structure and linkage disequilibrium, acquiring new phenotype data, and performing genome-wide association analysis to map quantitative trait loci. Expected results are manuscripts describing allelic diversity, population structure, linkage disequilibrium, and genomic locations of QTLs detected by association mapping in apple and peach.

1. WP4: Exploring the phenotypic and genetic diversity in European apple and peach germplasm collections and its exploitation by association genetics approach Maria José Aranzana IRTA, Spain

8. Expected results / outcomes M54 Submit manuscript of genomic location and effect of QTLs detected by GWA mapping in apple and peach. D4.4 M30 Submit manuscript with description and characterization of allelic diversity, population structure and LD in (i) peach (1250 CVs; 9K SNPs) and ii) apple (1900 CVs; 384 SNP) D4.3 M24 Database uploaded with already-available phenotypic characterization of the peach and apple D4.2 M12 Description of variability using available data in (i) 4 peach and (ii) in 5 apple germplasm collections D4.1 Delivery date Deliverable title Deliverable N°

9. Interactions planned with other WPs WP4 Variability and Association mapping WP1 MAB SNPs linked to traits WP3 PBA Complementary approaches WP5 Phenotyping methods Methods to phenotype novel traits WP6 Arrays development 384 and 50K apple SNP array WP7 Database Upload descriptive info WP8 Dissemination Booklets and training

10. Partners involved Apple Peach INRA INRA CRA-W IRTA READING CRA RBIPH ZJU UNIBO UMIL UMIL DLO DLO FEM FEM