Incidence of storage diseases on apples of selected cultivars and advanced selections grown with and without fungicide treatments

Natural occurrence of storage diseases was evaluated in 30 apple cultivars and hybrids stored at 1-2 deg C during a 3-year study. The apples were harvested in orchards with or without fungicide treatments. Bitter rot and grey mould were the most frequent diseases, followed by blue mould and brown rot. Fungicide treatments applied in the orchard with integrated plant protection reduced the total fruit rotting by two to four times. Significant losses caused by rotting usually took place in the last quarter of the normal storage life of each cultivar, but in the case of samples treated with fungicides, it was mostly during the last month. Cultivars Angold, Gala, Florina, Melodie, and Meteor proved to be partially resistant to the storage diseases, but the smallest shares of rotted fruits were recorded on apples of Zuzana and Melrose cultivars. Five advanced selections proved to be still less affected by fruit rotting as Melrose and Zuzana, from which HL 237 and HL 390 were the most remarkable. The majority of selections with resistance to storage diseases as well as Zuzana cv. contain Glockenapfel cv. in their pedigree.