Identification of QTLs for Fruit Quality Traits in Apricot

Fruit quality is one of the main bottlenecks for apricot consumers. Despite the relevance of phenotyping during the field evaluation phase in breeding programmes, the molecular bases of fruit quality have been poorly investigated. The identification of genomic regions involved in fruit quality traits can be pursued by joining the phenotypic data with a molecular-based approach. The related QTL definition offers the opportunity to optimize the apricot breeding programmes by introducing an early marker assisted selection (MAS), and identify candidate genes related to these traits. These are the main objectives of the ISAFRUIT WP6.1 European IP Project concerning peach, apricot and apple fruits. On apricot, INRA UGAFL Avignon (Fr) and DCA, University of Bologna (It) were in charge of the characterization of two apricot populations: 'Goldrich' x 'Moniqui' and 'Lito x BO81604311' (of about 120 seedlings each). Both progenies have been characterized over two consecutive years for several physical and chemical characters (blooming and maturity dates, fresh weight, firmness, colour, dry matter, kernel weight, flesh adhesion, acid and sugar contents). Genetic linkage maps of each population were constructed by SSRs markers and QTLs analyses were performed for all the investigated quality traits. Several QTLs, distributed in all the linkage groups, were detected in both populations for all the analyzed traits except fruit firmness. A good QTL stability was observed between years and this offers an interesting opportunity to use the related markers in an MAS process.