Genetic studies of powdery mildew resistance in cultivated oat (Avena sativa L.) II. Cultivars and breeding lines grown in Northern and Eastern Europe

Cultivated oat (Avena sativa L.) varieties and lines grown in Northern and Eastern European countries were tested for powdery mildew resistance using eleven Erysiphe graminis f. sp. avenae isolates, which possess the ability to differentiate the five oat powdery mildew resistance (OMR) groups. About 5% from a total of 207 accessions possessed resistance which was attributa ble to either documented resistance or to disease response patterns previou sly not vet detected. Five cultivars and lines showed the resistance of OMR group 1, one cultivar possessed the resistance of OMR group 3, one line re vealed the resistance of OMR 3 in combination with an additional resistance and 3 cultivars exhibited a resistant response pattern not yet characteriz ed.