Virulence of North American and European Races of Puccinia striiformis on North American, World, and European Differential Wheat Cultivars

Cultures of North American and European races of Puccinia striiformis were compared on North American (NA) and world/European (W/E) wheat (Triticum aestivum) differential cultivars. Races virulent on cultivar Fielder were virulent on cultivar Heines Kolben (resistance gene Yr6), and those virulent on Fielder and Heines VII were virulent on Heines Peko (Yr2 + Yr6). Cultivars Strubes Dickkopf and North Desprez (Yr3a + Yr4a) provided additional differentiation of the North American races, and cultivar Stephens provided additional differentiation of the European races (...)