Submitted to: Phytopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/26/1996
Publication Date: N/A
Interpretive Summary: Stripe rust of wheat is especially destructive in the western United States. The most economical and environmentally safe method of controlling the disease is growing resistant varieties. Wheat varieties Druchamp, Stephens, Nord Desprez, Minister, Vilmorin 23, Yamhill, and Hybrid 46 have two or three genes for stripe rust resistance. To determine the chromosomal locations of these genes, the seven varieties were crossed with the normal Chinese Spring that has 42 chromosomes (21 pairs of chromosomes) and a complete set of Chinese Spring lines with one chromosome or one chromosome plus a chromosome arm missing. Based on cytogenetic analyses, the two genes and one previously undescribed gene in Druchamp are located on chromosomes 1B, 5B, and 6A; the genes and one previously undescribed gene in Stephens are located on chromosomes 1B, 2B, and 3B; the two genes in Nord Desprez and two genes in Minister are located on chromosomes 1B and 4A; the two genes in Vilmorin 23 are located on chromosomes 2B and 6B; the three genes in Yamhill are located on chromosomes 4B, 6B, and 7B; and the two genes in Hybrid 46 are located on chromosomes 6A and 6B. The information is useful in breeding resistant varieties and in understanding the interactions of wheat varieties and stripe rust races.
Technical Abstract: Wheat (Triticum aestivum L.) cultivars Druchamp, Stephens, Nord Desprez, Minister, Vilmorin 23, Yamhill, and Hybrid 46 have been reported to have genes Yr3a and YrDru; Yr3a and YrSte; Yr3a and YrND; Yr3c and YrMin; Yr4a and YrV23; Yr2, Yr4a, and YrYam; and Yr4b and YrH46, respectively, for resistance to Puccinia striiformis West., the causal agent of stripe rust. To determine the chromosomal locations of the genes, the seven cultivars were crossed with disomic Chinese Spring and a set of 21 monotelosomic or monosomic Chinese Spring lines. Somatic chromosome number in parental, F1, and some F2 plants were determined in Feulgen stained root tip cells. The monosomic F1 plants were selfed to produce F2 seeds. F2 and parental seedlings were tested under controlled conditions with North American races of P. striiformis. The results confirm that Yr2 is on chromosome 7B and show that Yr3a and Yr3b are on chromosome 1B; Yr4a and Yr4b are on chromosome 6B; YrMin and YrND are chromosome 4A; YrDru is on chromosome 5B; YrSte is on chromosome 2B; YrH46 and a previously undescribed gene (YrDru2) in Druchamp are on chromosome 6A; a gene in Stephens previously undescribed (YrSte2) is on chromosome 3B; Yr23 is on chromosome 2B; and YrYam in Yamhill is on chromosome 4B.