Wildspecies Apple: Malus ×robusta

This datasheet aims to describe the Malus hybrid species Malus ×robusta (Carrière) Rehder. This secondary species possesses benefi cial resistances to diseases. International breeding programs like the breeding program at the Julius Kühn-Institut (JKI), Institute for Breeding Research on Horticultural and Fruit Crops in Dresden-Pillnitz (ZGO) focus on the genotype Malus ×robusta No. 5. As the name “robusta” implies, Malus ×robusta 5 represents an important genetic resource for breeding of disease resistance. As donor for fi re blight resistance it mainly became importance in the Geneva® USDA/Cornell Apple Rootstock Breeding program of the Cornell University, New York. Currently, the molecular background of the resistance mechanism is investigated at ZGO. The datasheet contains the classifi cation and a description of a few accessions of Malus ×robusta (Carrière) Rehder. The Malus ×robusta accessions maintained at the German National Fruit Collection which belongs to ZGO are characterized and evaluated for resistance to some important diseases of apple. The results of a genetic fi nger print enable the diff erentiation between the accessions of Malus ×robusta (Carrière) Rehder.