Chromosomal location of genes for resistance to Puccinia striiformis in seven wheat cultivars with resistance genes at the Yr3 and Yr4 loci

Wheat cvs. Hybrid 46, Minister, Vilmorin 23, Druchamp, Stephens, Nord Desprez, and Yamhill have genes for resistance to Puccinia striiformis f. sp. tritici at the Yr3 or Yr4 loci as well as at other loci. To determine the chromosomal locations of the genes, the cultivars were crossed with seedling-susceptible cv. Chinese Spring and a set of 21 Chinese Spring aneuploids. F-2 seed was obtained from self-pollinated monosomic F-1 plants. Seedlings of F-2 plants and their parents were inoculated with North American races of P. striiformis f. sp. tritici. The results show that Yr3a in Druchamp, Stephens, and Nord Desprez and Yr3c in Minister are located on chromosome 1B; Yr4a in Vilmorin 23 and Yamhill and Yr4b in Hybrid 46 are on chromosome 6B; YrMin in Minister and YrND in Nord Desprez are on chromosome 4A; YrDru in Druchamp is on chromosome 5B; YrSte in Stephens is on chromosome 2B; YrH46 in Hybrid 46 and a previously undescribed gene (YrDru2) in Druchamp are on chromosome 6A; a gent in Stephens previously undescribed (YrSte2) is on chromosome 3B; YrV23 in Vilmorin 23 is on chromosome 2B; Yr2 in Yamhill is on chromosome 7B; and YrYam in Yamhill is on chromosome 4B.