Cultivated oat (Avenu sativa L.) varieties and lines grown in Northern and Eastern European countries were tested for powdery mildew resistance using eleven Erysiphe graminis f. sp. avenue 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 attributable to either documented resistance or to disease response patterns previously not yet detected. Five cultivars and lines showed the resistance of OMR group I, one cultivar possessed the resistance of OMR group 3, one line revealed the resistance of OMR 3 in combination with an additional resistance and 3 cultivars exhibited a resistant response pattern not yet characterized.

No abstract

A total of 50 common wheat Cultivars and advanced breeding lines grown in Western Siberia were tested with a set of eleven differential powdery mildew isolates. Thirteen cultivars were susceptible and seven Cultivars showed susceptible and intermediate responses. Eight cultivars revealed the response pattern of individual resistance genes Pm2, Pm4b, Pm6, Pm8, and Mlar, respectively. Eleven cultivars exhibited the response pattern documented for two resistance genes in combination. Seven cultivars expressed the response pattern of Pm6 in combination with either Pm2, Pm4b, or Pm8, another three cultivars the combination of Pm4b with either Mlar or Pm1. In addition, two cultivars responded to the pattern of gene Pm8 in combination with either gene pm5 or Pm6. One cultivar exhibited the combination of three genes Pm1 + Pm2 + Pm6, and two cultivars Pm1 + pm5 + Pm8. Eight cultivars revealed isolate‐specific response patterns that could not be attributed to resistance genes or gene combinations present in the differential cultivars/lines.

No abstract