|Jones Stephen S|
Submitted to: Phytopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/13/1994
Publication Date: N/A
Citation: 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. Spring wheat varieties Compair, Fielder, and Lee each have two genes and Lemhi has one gene for stripe rust resistance. To determine the chromosomal locations of fthese genes, the four varieties were crossed with the normal Chinese Sprin that has 42 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 in Compair are located on chromosomes 2D and 5B; the two genes in Fielder are located on chromosomes 7B and 6D; the two genes in Lee are located on chromosomes 4D and 6D; and the gene in Lemhi is located on chromosome 1B. The information is useful in breeding resistant varieties and in understanding the interactions of wheat varieties and stripe rust races.
Technical Abstract: Spring wheat (Triticum aestivum) cultivars Compair, Fielder, Lee, and Lemhi have been reported to have genes Yr8 and YrCom, Yr6 and YrFie, YrLe1 and YrLe2, and YrLem, respectively, for resistance to Puccinia striiformis, the causal agent of stripe rust. To determine the chromosomal locations of the genes, the four 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 confirmed that Yr6 is on chromosome 7B and Yr8 is on chromosome 2D and show that YrCom is on chromosome 5B; YrFie is on chromosome 6D; YrLem is on chromosome 1B; YrLe1 is on chromosome 4D; and YrLe2 in Lee is on chromosome e6D. We propose official gene designations Yr19 for YrCom, Yr20 for YrFie, Yr21 forYrLem, Yr22 for YrLe1, and Yr23 for YrLe2.