Author
ZHOU, XINLI - Washington State University | |
REN, RUSHENG - Washington State University | |
WANGE, MEINAN - Washington State University | |
Chen, Xianming |
Submitted to: American Phytopathological Society
Publication Type: Abstract Only Publication Acceptance Date: 4/1/2011 Publication Date: N/A Citation: N/A Interpretive Summary: New genes are essential for breeding wheat cultivars with effective resistance against stripe rust. Spring wheat germplasms PI 178759 and PI 183527 were identified to have high-levels of resistance in fields in 2004 to 2010. Further testing under controlled greenhouse conditions with individual races showed that PI 183527 had a typical high-temperature adult-plant (HTAP) resistance while the HTAP resistance in PI 178759 was more temperature-sensitive. The genotypes were crossed with susceptible spring wheat Avocet. Genetic analysis identified two genes in PI 178759 and one gene in PI 183527 using stripe rust data of progenies tested with individual stripe rust races under the controlled greenhouse conditions and in the field under natural infection of the pathogen. Molecular mapping using resistance gene analog polymorphism and simple sequence repeat (SSR) markers located the three genes on the long arm of chromosome 7B. The two genes in PI 178759 were 39.1 cM away. One of the PI 178759 genes was linked in repulsion with the PI 183527 gene. Both genes were flanked by two SSR markers, which will be useful for marker-assisted selection. Allelism testing is underway to determine if the two genes are at different loci. Based on the types of resistance, the genes in PI 178759 and PI 183527 appeared to be different from previously identified genes and should be useful for developing wheat cultivars with durable resistance to stripe rust. Technical Abstract: New genes are essential for breeding wheat cultivars with effective resistance against stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst). Spring wheat PI 178759 and PI 183527 were identified to have high-levels of resistance in fields in 2004 to 2010. Further testing under controlled greenhouse conditions with individual races showed that PI 183527 had a typical high-temperature adult-plant (HTAP) resistance while the HTAP resistance in PI 178759 was more temperature-sensitive. The genotypes were crossed with susceptible spring wheat Avocet. Genetic analysis identified two genes in PI 178759 and one gene in PI 183527 using the phenotypic data of F2 and F3 tested with individual Pst races under the controlled greenhouse conditions and of F3 tested in the field under natural infection of the pathogen. Molecular mapping using resistance gene analog polymorphism and simple sequence repeat (SSR) markers located the three genes on the long arm of chromosome 7B. The two genes in PI 178759 were 39.1 cM away. One of the PI 178759 genes was linked in repulsion with the PI 183527 gene. Both genes were flanked by SSR markers Xbarc182 and Xcfa2040. Allelism testing is underway to determine if the two genes are at different loci. Based on the types of resistance, the genes in PI 178759 and PI 183527 appeared to be different from previously identified genes and should be useful for developing wheat cultivars with durable resistance to stripe rust. |