Evaluation of fruit genetic resources for disease resistance
Abstract: A field survey throughout Switzerland established an inventory of fruit genetic resources. The decentralised collections network was subsequently completed and the characterization of the accessions is ongoing. Considering international standards, guidelines for the phenotypic description of the fruit genetic resources were developed and practically applied. Apple accessions from the Swiss pool of genetic resources were tested for fire blight (Erwinia amylovora) resistance in the greenhouse. Results of the fire blight screening confirm significant differences between accessions. Additionally, the accessions were analysed with SCAR markers surrounding a QTL for fire blight tolerance. Moreover, young trees of 600 accessions were planted to evaluate their scab (Venturia inaequalis) and powdery mildew (Podosphaera leucotricha) resistance in a field trial. The project aims at defining accessions useful for cultivation as standard trees for cider and juice production and that are an important landscaping and ecological factor. Promising accessions are being used for breeding.